1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * ipmi_msghandler.c
4  *
5  * Incoming and outgoing message routing for an IPMI interface.
6  *
7  * Author: MontaVista Software, Inc.
8  *         Corey Minyard <minyard@mvista.com>
9  *         source@mvista.com
10  *
11  * Copyright 2002 MontaVista Software Inc.
12  */
13 
14 #define pr_fmt(fmt) "IPMI message handler: " fmt
15 #define dev_fmt(fmt) pr_fmt(fmt)
16 
17 #include <linux/module.h>
18 #include <linux/errno.h>
19 #include <linux/panic_notifier.h>
20 #include <linux/poll.h>
21 #include <linux/sched.h>
22 #include <linux/seq_file.h>
23 #include <linux/spinlock.h>
24 #include <linux/mutex.h>
25 #include <linux/slab.h>
26 #include <linux/ipmi.h>
27 #include <linux/ipmi_smi.h>
28 #include <linux/notifier.h>
29 #include <linux/init.h>
30 #include <linux/proc_fs.h>
31 #include <linux/rcupdate.h>
32 #include <linux/interrupt.h>
33 #include <linux/moduleparam.h>
34 #include <linux/workqueue.h>
35 #include <linux/uuid.h>
36 #include <linux/nospec.h>
37 #include <linux/vmalloc.h>
38 #include <linux/delay.h>
39 
40 #define IPMI_DRIVER_VERSION "39.2"
41 
42 static struct ipmi_recv_msg *ipmi_alloc_recv_msg(void);
43 static int ipmi_init_msghandler(void);
44 static void smi_recv_tasklet(struct tasklet_struct *t);
45 static void handle_new_recv_msgs(struct ipmi_smi *intf);
46 static void need_waiter(struct ipmi_smi *intf);
47 static int handle_one_recv_msg(struct ipmi_smi *intf,
48 			       struct ipmi_smi_msg *msg);
49 
50 static bool initialized;
51 static bool drvregistered;
52 
53 /* Numbers in this enumerator should be mapped to ipmi_panic_event_str */
54 enum ipmi_panic_event_op {
55 	IPMI_SEND_PANIC_EVENT_NONE,
56 	IPMI_SEND_PANIC_EVENT,
57 	IPMI_SEND_PANIC_EVENT_STRING,
58 	IPMI_SEND_PANIC_EVENT_MAX
59 };
60 
61 /* Indices in this array should be mapped to enum ipmi_panic_event_op */
62 static const char *const ipmi_panic_event_str[] = { "none", "event", "string", NULL };
63 
64 #ifdef CONFIG_IPMI_PANIC_STRING
65 #define IPMI_PANIC_DEFAULT IPMI_SEND_PANIC_EVENT_STRING
66 #elif defined(CONFIG_IPMI_PANIC_EVENT)
67 #define IPMI_PANIC_DEFAULT IPMI_SEND_PANIC_EVENT
68 #else
69 #define IPMI_PANIC_DEFAULT IPMI_SEND_PANIC_EVENT_NONE
70 #endif
71 
72 static enum ipmi_panic_event_op ipmi_send_panic_event = IPMI_PANIC_DEFAULT;
73 
panic_op_write_handler(const char * val,const struct kernel_param * kp)74 static int panic_op_write_handler(const char *val,
75 				  const struct kernel_param *kp)
76 {
77 	char valcp[16];
78 	int e;
79 
80 	strscpy(valcp, val, sizeof(valcp));
81 	e = match_string(ipmi_panic_event_str, -1, strstrip(valcp));
82 	if (e < 0)
83 		return e;
84 
85 	ipmi_send_panic_event = e;
86 	return 0;
87 }
88 
panic_op_read_handler(char * buffer,const struct kernel_param * kp)89 static int panic_op_read_handler(char *buffer, const struct kernel_param *kp)
90 {
91 	const char *event_str;
92 
93 	if (ipmi_send_panic_event >= IPMI_SEND_PANIC_EVENT_MAX)
94 		event_str = "???";
95 	else
96 		event_str = ipmi_panic_event_str[ipmi_send_panic_event];
97 
98 	return sprintf(buffer, "%s\n", event_str);
99 }
100 
101 static const struct kernel_param_ops panic_op_ops = {
102 	.set = panic_op_write_handler,
103 	.get = panic_op_read_handler
104 };
105 module_param_cb(panic_op, &panic_op_ops, NULL, 0600);
106 MODULE_PARM_DESC(panic_op, "Sets if the IPMI driver will attempt to store panic information in the event log in the event of a panic.  Set to 'none' for no, 'event' for a single event, or 'string' for a generic event and the panic string in IPMI OEM events.");
107 
108 
109 #define MAX_EVENTS_IN_QUEUE	25
110 
111 /* Remain in auto-maintenance mode for this amount of time (in ms). */
112 static unsigned long maintenance_mode_timeout_ms = 30000;
113 module_param(maintenance_mode_timeout_ms, ulong, 0644);
114 MODULE_PARM_DESC(maintenance_mode_timeout_ms,
115 		 "The time (milliseconds) after the last maintenance message that the connection stays in maintenance mode.");
116 
117 /*
118  * Don't let a message sit in a queue forever, always time it with at lest
119  * the max message timer.  This is in milliseconds.
120  */
121 #define MAX_MSG_TIMEOUT		60000
122 
123 /*
124  * Timeout times below are in milliseconds, and are done off a 1
125  * second timer.  So setting the value to 1000 would mean anything
126  * between 0 and 1000ms.  So really the only reasonable minimum
127  * setting it 2000ms, which is between 1 and 2 seconds.
128  */
129 
130 /* The default timeout for message retries. */
131 static unsigned long default_retry_ms = 2000;
132 module_param(default_retry_ms, ulong, 0644);
133 MODULE_PARM_DESC(default_retry_ms,
134 		 "The time (milliseconds) between retry sends");
135 
136 /* The default timeout for maintenance mode message retries. */
137 static unsigned long default_maintenance_retry_ms = 3000;
138 module_param(default_maintenance_retry_ms, ulong, 0644);
139 MODULE_PARM_DESC(default_maintenance_retry_ms,
140 		 "The time (milliseconds) between retry sends in maintenance mode");
141 
142 /* The default maximum number of retries */
143 static unsigned int default_max_retries = 4;
144 module_param(default_max_retries, uint, 0644);
145 MODULE_PARM_DESC(default_max_retries,
146 		 "The time (milliseconds) between retry sends in maintenance mode");
147 
148 /* The default maximum number of users that may register. */
149 static unsigned int max_users = 30;
150 module_param(max_users, uint, 0644);
151 MODULE_PARM_DESC(max_users,
152 		 "The most users that may use the IPMI stack at one time.");
153 
154 /* The default maximum number of message a user may have outstanding. */
155 static unsigned int max_msgs_per_user = 100;
156 module_param(max_msgs_per_user, uint, 0644);
157 MODULE_PARM_DESC(max_msgs_per_user,
158 		 "The most message a user may have outstanding.");
159 
160 /* Call every ~1000 ms. */
161 #define IPMI_TIMEOUT_TIME	1000
162 
163 /* How many jiffies does it take to get to the timeout time. */
164 #define IPMI_TIMEOUT_JIFFIES	((IPMI_TIMEOUT_TIME * HZ) / 1000)
165 
166 /*
167  * Request events from the queue every second (this is the number of
168  * IPMI_TIMEOUT_TIMES between event requests).  Hopefully, in the
169  * future, IPMI will add a way to know immediately if an event is in
170  * the queue and this silliness can go away.
171  */
172 #define IPMI_REQUEST_EV_TIME	(1000 / (IPMI_TIMEOUT_TIME))
173 
174 /* How long should we cache dynamic device IDs? */
175 #define IPMI_DYN_DEV_ID_EXPIRY	(10 * HZ)
176 
177 /*
178  * The main "user" data structure.
179  */
180 struct ipmi_user {
181 	struct list_head link;
182 
183 	/*
184 	 * Set to NULL when the user is destroyed, a pointer to myself
185 	 * so srcu_dereference can be used on it.
186 	 */
187 	struct ipmi_user *self;
188 	struct srcu_struct release_barrier;
189 
190 	struct kref refcount;
191 
192 	/* The upper layer that handles receive messages. */
193 	const struct ipmi_user_hndl *handler;
194 	void             *handler_data;
195 
196 	/* The interface this user is bound to. */
197 	struct ipmi_smi *intf;
198 
199 	/* Does this interface receive IPMI events? */
200 	bool gets_events;
201 
202 	atomic_t nr_msgs;
203 
204 	/* Free must run in process context for RCU cleanup. */
205 	struct work_struct remove_work;
206 };
207 
208 static struct workqueue_struct *remove_work_wq;
209 
acquire_ipmi_user(struct ipmi_user * user,int * index)210 static struct ipmi_user *acquire_ipmi_user(struct ipmi_user *user, int *index)
211 	__acquires(user->release_barrier)
212 {
213 	struct ipmi_user *ruser;
214 
215 	*index = srcu_read_lock(&user->release_barrier);
216 	ruser = srcu_dereference(user->self, &user->release_barrier);
217 	if (!ruser)
218 		srcu_read_unlock(&user->release_barrier, *index);
219 	return ruser;
220 }
221 
release_ipmi_user(struct ipmi_user * user,int index)222 static void release_ipmi_user(struct ipmi_user *user, int index)
223 {
224 	srcu_read_unlock(&user->release_barrier, index);
225 }
226 
227 struct cmd_rcvr {
228 	struct list_head link;
229 
230 	struct ipmi_user *user;
231 	unsigned char netfn;
232 	unsigned char cmd;
233 	unsigned int  chans;
234 
235 	/*
236 	 * This is used to form a linked lised during mass deletion.
237 	 * Since this is in an RCU list, we cannot use the link above
238 	 * or change any data until the RCU period completes.  So we
239 	 * use this next variable during mass deletion so we can have
240 	 * a list and don't have to wait and restart the search on
241 	 * every individual deletion of a command.
242 	 */
243 	struct cmd_rcvr *next;
244 };
245 
246 struct seq_table {
247 	unsigned int         inuse : 1;
248 	unsigned int         broadcast : 1;
249 
250 	unsigned long        timeout;
251 	unsigned long        orig_timeout;
252 	unsigned int         retries_left;
253 
254 	/*
255 	 * To verify on an incoming send message response that this is
256 	 * the message that the response is for, we keep a sequence id
257 	 * and increment it every time we send a message.
258 	 */
259 	long                 seqid;
260 
261 	/*
262 	 * This is held so we can properly respond to the message on a
263 	 * timeout, and it is used to hold the temporary data for
264 	 * retransmission, too.
265 	 */
266 	struct ipmi_recv_msg *recv_msg;
267 };
268 
269 /*
270  * Store the information in a msgid (long) to allow us to find a
271  * sequence table entry from the msgid.
272  */
273 #define STORE_SEQ_IN_MSGID(seq, seqid) \
274 	((((seq) & 0x3f) << 26) | ((seqid) & 0x3ffffff))
275 
276 #define GET_SEQ_FROM_MSGID(msgid, seq, seqid) \
277 	do {								\
278 		seq = (((msgid) >> 26) & 0x3f);				\
279 		seqid = ((msgid) & 0x3ffffff);				\
280 	} while (0)
281 
282 #define NEXT_SEQID(seqid) (((seqid) + 1) & 0x3ffffff)
283 
284 #define IPMI_MAX_CHANNELS       16
285 struct ipmi_channel {
286 	unsigned char medium;
287 	unsigned char protocol;
288 };
289 
290 struct ipmi_channel_set {
291 	struct ipmi_channel c[IPMI_MAX_CHANNELS];
292 };
293 
294 struct ipmi_my_addrinfo {
295 	/*
296 	 * My slave address.  This is initialized to IPMI_BMC_SLAVE_ADDR,
297 	 * but may be changed by the user.
298 	 */
299 	unsigned char address;
300 
301 	/*
302 	 * My LUN.  This should generally stay the SMS LUN, but just in
303 	 * case...
304 	 */
305 	unsigned char lun;
306 };
307 
308 /*
309  * Note that the product id, manufacturer id, guid, and device id are
310  * immutable in this structure, so dyn_mutex is not required for
311  * accessing those.  If those change on a BMC, a new BMC is allocated.
312  */
313 struct bmc_device {
314 	struct platform_device pdev;
315 	struct list_head       intfs; /* Interfaces on this BMC. */
316 	struct ipmi_device_id  id;
317 	struct ipmi_device_id  fetch_id;
318 	int                    dyn_id_set;
319 	unsigned long          dyn_id_expiry;
320 	struct mutex           dyn_mutex; /* Protects id, intfs, & dyn* */
321 	guid_t                 guid;
322 	guid_t                 fetch_guid;
323 	int                    dyn_guid_set;
324 	struct kref	       usecount;
325 	struct work_struct     remove_work;
326 	unsigned char	       cc; /* completion code */
327 };
328 #define to_bmc_device(x) container_of((x), struct bmc_device, pdev.dev)
329 
330 static int bmc_get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc,
331 			     struct ipmi_device_id *id,
332 			     bool *guid_set, guid_t *guid);
333 
334 /*
335  * Various statistics for IPMI, these index stats[] in the ipmi_smi
336  * structure.
337  */
338 enum ipmi_stat_indexes {
339 	/* Commands we got from the user that were invalid. */
340 	IPMI_STAT_sent_invalid_commands = 0,
341 
342 	/* Commands we sent to the MC. */
343 	IPMI_STAT_sent_local_commands,
344 
345 	/* Responses from the MC that were delivered to a user. */
346 	IPMI_STAT_handled_local_responses,
347 
348 	/* Responses from the MC that were not delivered to a user. */
349 	IPMI_STAT_unhandled_local_responses,
350 
351 	/* Commands we sent out to the IPMB bus. */
352 	IPMI_STAT_sent_ipmb_commands,
353 
354 	/* Commands sent on the IPMB that had errors on the SEND CMD */
355 	IPMI_STAT_sent_ipmb_command_errs,
356 
357 	/* Each retransmit increments this count. */
358 	IPMI_STAT_retransmitted_ipmb_commands,
359 
360 	/*
361 	 * When a message times out (runs out of retransmits) this is
362 	 * incremented.
363 	 */
364 	IPMI_STAT_timed_out_ipmb_commands,
365 
366 	/*
367 	 * This is like above, but for broadcasts.  Broadcasts are
368 	 * *not* included in the above count (they are expected to
369 	 * time out).
370 	 */
371 	IPMI_STAT_timed_out_ipmb_broadcasts,
372 
373 	/* Responses I have sent to the IPMB bus. */
374 	IPMI_STAT_sent_ipmb_responses,
375 
376 	/* The response was delivered to the user. */
377 	IPMI_STAT_handled_ipmb_responses,
378 
379 	/* The response had invalid data in it. */
380 	IPMI_STAT_invalid_ipmb_responses,
381 
382 	/* The response didn't have anyone waiting for it. */
383 	IPMI_STAT_unhandled_ipmb_responses,
384 
385 	/* Commands we sent out to the IPMB bus. */
386 	IPMI_STAT_sent_lan_commands,
387 
388 	/* Commands sent on the IPMB that had errors on the SEND CMD */
389 	IPMI_STAT_sent_lan_command_errs,
390 
391 	/* Each retransmit increments this count. */
392 	IPMI_STAT_retransmitted_lan_commands,
393 
394 	/*
395 	 * When a message times out (runs out of retransmits) this is
396 	 * incremented.
397 	 */
398 	IPMI_STAT_timed_out_lan_commands,
399 
400 	/* Responses I have sent to the IPMB bus. */
401 	IPMI_STAT_sent_lan_responses,
402 
403 	/* The response was delivered to the user. */
404 	IPMI_STAT_handled_lan_responses,
405 
406 	/* The response had invalid data in it. */
407 	IPMI_STAT_invalid_lan_responses,
408 
409 	/* The response didn't have anyone waiting for it. */
410 	IPMI_STAT_unhandled_lan_responses,
411 
412 	/* The command was delivered to the user. */
413 	IPMI_STAT_handled_commands,
414 
415 	/* The command had invalid data in it. */
416 	IPMI_STAT_invalid_commands,
417 
418 	/* The command didn't have anyone waiting for it. */
419 	IPMI_STAT_unhandled_commands,
420 
421 	/* Invalid data in an event. */
422 	IPMI_STAT_invalid_events,
423 
424 	/* Events that were received with the proper format. */
425 	IPMI_STAT_events,
426 
427 	/* Retransmissions on IPMB that failed. */
428 	IPMI_STAT_dropped_rexmit_ipmb_commands,
429 
430 	/* Retransmissions on LAN that failed. */
431 	IPMI_STAT_dropped_rexmit_lan_commands,
432 
433 	/* This *must* remain last, add new values above this. */
434 	IPMI_NUM_STATS
435 };
436 
437 
438 #define IPMI_IPMB_NUM_SEQ	64
439 struct ipmi_smi {
440 	struct module *owner;
441 
442 	/* What interface number are we? */
443 	int intf_num;
444 
445 	struct kref refcount;
446 
447 	/* Set when the interface is being unregistered. */
448 	bool in_shutdown;
449 
450 	/* Used for a list of interfaces. */
451 	struct list_head link;
452 
453 	/*
454 	 * The list of upper layers that are using me.  seq_lock write
455 	 * protects this.  Read protection is with srcu.
456 	 */
457 	struct list_head users;
458 	struct srcu_struct users_srcu;
459 	atomic_t nr_users;
460 	struct device_attribute nr_users_devattr;
461 	struct device_attribute nr_msgs_devattr;
462 
463 
464 	/* Used for wake ups at startup. */
465 	wait_queue_head_t waitq;
466 
467 	/*
468 	 * Prevents the interface from being unregistered when the
469 	 * interface is used by being looked up through the BMC
470 	 * structure.
471 	 */
472 	struct mutex bmc_reg_mutex;
473 
474 	struct bmc_device tmp_bmc;
475 	struct bmc_device *bmc;
476 	bool bmc_registered;
477 	struct list_head bmc_link;
478 	char *my_dev_name;
479 	bool in_bmc_register;  /* Handle recursive situations.  Yuck. */
480 	struct work_struct bmc_reg_work;
481 
482 	const struct ipmi_smi_handlers *handlers;
483 	void                     *send_info;
484 
485 	/* Driver-model device for the system interface. */
486 	struct device          *si_dev;
487 
488 	/*
489 	 * A table of sequence numbers for this interface.  We use the
490 	 * sequence numbers for IPMB messages that go out of the
491 	 * interface to match them up with their responses.  A routine
492 	 * is called periodically to time the items in this list.
493 	 */
494 	spinlock_t       seq_lock;
495 	struct seq_table seq_table[IPMI_IPMB_NUM_SEQ];
496 	int curr_seq;
497 
498 	/*
499 	 * Messages queued for delivery.  If delivery fails (out of memory
500 	 * for instance), They will stay in here to be processed later in a
501 	 * periodic timer interrupt.  The tasklet is for handling received
502 	 * messages directly from the handler.
503 	 */
504 	spinlock_t       waiting_rcv_msgs_lock;
505 	struct list_head waiting_rcv_msgs;
506 	atomic_t	 watchdog_pretimeouts_to_deliver;
507 	struct tasklet_struct recv_tasklet;
508 
509 	spinlock_t             xmit_msgs_lock;
510 	struct list_head       xmit_msgs;
511 	struct ipmi_smi_msg    *curr_msg;
512 	struct list_head       hp_xmit_msgs;
513 
514 	/*
515 	 * The list of command receivers that are registered for commands
516 	 * on this interface.
517 	 */
518 	struct mutex     cmd_rcvrs_mutex;
519 	struct list_head cmd_rcvrs;
520 
521 	/*
522 	 * Events that were queues because no one was there to receive
523 	 * them.
524 	 */
525 	spinlock_t       events_lock; /* For dealing with event stuff. */
526 	struct list_head waiting_events;
527 	unsigned int     waiting_events_count; /* How many events in queue? */
528 	char             delivering_events;
529 	char             event_msg_printed;
530 
531 	/* How many users are waiting for events? */
532 	atomic_t         event_waiters;
533 	unsigned int     ticks_to_req_ev;
534 
535 	spinlock_t       watch_lock; /* For dealing with watch stuff below. */
536 
537 	/* How many users are waiting for commands? */
538 	unsigned int     command_waiters;
539 
540 	/* How many users are waiting for watchdogs? */
541 	unsigned int     watchdog_waiters;
542 
543 	/* How many users are waiting for message responses? */
544 	unsigned int     response_waiters;
545 
546 	/*
547 	 * Tells what the lower layer has last been asked to watch for,
548 	 * messages and/or watchdogs.  Protected by watch_lock.
549 	 */
550 	unsigned int     last_watch_mask;
551 
552 	/*
553 	 * The event receiver for my BMC, only really used at panic
554 	 * shutdown as a place to store this.
555 	 */
556 	unsigned char event_receiver;
557 	unsigned char event_receiver_lun;
558 	unsigned char local_sel_device;
559 	unsigned char local_event_generator;
560 
561 	/* For handling of maintenance mode. */
562 	int maintenance_mode;
563 	bool maintenance_mode_enable;
564 	int auto_maintenance_timeout;
565 	spinlock_t maintenance_mode_lock; /* Used in a timer... */
566 
567 	/*
568 	 * If we are doing maintenance on something on IPMB, extend
569 	 * the timeout time to avoid timeouts writing firmware and
570 	 * such.
571 	 */
572 	int ipmb_maintenance_mode_timeout;
573 
574 	/*
575 	 * A cheap hack, if this is non-null and a message to an
576 	 * interface comes in with a NULL user, call this routine with
577 	 * it.  Note that the message will still be freed by the
578 	 * caller.  This only works on the system interface.
579 	 *
580 	 * Protected by bmc_reg_mutex.
581 	 */
582 	void (*null_user_handler)(struct ipmi_smi *intf,
583 				  struct ipmi_recv_msg *msg);
584 
585 	/*
586 	 * When we are scanning the channels for an SMI, this will
587 	 * tell which channel we are scanning.
588 	 */
589 	int curr_channel;
590 
591 	/* Channel information */
592 	struct ipmi_channel_set *channel_list;
593 	unsigned int curr_working_cset; /* First index into the following. */
594 	struct ipmi_channel_set wchannels[2];
595 	struct ipmi_my_addrinfo addrinfo[IPMI_MAX_CHANNELS];
596 	bool channels_ready;
597 
598 	atomic_t stats[IPMI_NUM_STATS];
599 
600 	/*
601 	 * run_to_completion duplicate of smb_info, smi_info
602 	 * and ipmi_serial_info structures. Used to decrease numbers of
603 	 * parameters passed by "low" level IPMI code.
604 	 */
605 	int run_to_completion;
606 };
607 #define to_si_intf_from_dev(device) container_of(device, struct ipmi_smi, dev)
608 
609 static void __get_guid(struct ipmi_smi *intf);
610 static void __ipmi_bmc_unregister(struct ipmi_smi *intf);
611 static int __ipmi_bmc_register(struct ipmi_smi *intf,
612 			       struct ipmi_device_id *id,
613 			       bool guid_set, guid_t *guid, int intf_num);
614 static int __scan_channels(struct ipmi_smi *intf, struct ipmi_device_id *id);
615 
616 
617 /**
618  * The driver model view of the IPMI messaging driver.
619  */
620 static struct platform_driver ipmidriver = {
621 	.driver = {
622 		.name = "ipmi",
623 		.bus = &platform_bus_type
624 	}
625 };
626 /*
627  * This mutex keeps us from adding the same BMC twice.
628  */
629 static DEFINE_MUTEX(ipmidriver_mutex);
630 
631 static LIST_HEAD(ipmi_interfaces);
632 static DEFINE_MUTEX(ipmi_interfaces_mutex);
633 #define ipmi_interfaces_mutex_held() \
634 	lockdep_is_held(&ipmi_interfaces_mutex)
635 static struct srcu_struct ipmi_interfaces_srcu;
636 
637 /*
638  * List of watchers that want to know when smi's are added and deleted.
639  */
640 static LIST_HEAD(smi_watchers);
641 static DEFINE_MUTEX(smi_watchers_mutex);
642 
643 #define ipmi_inc_stat(intf, stat) \
644 	atomic_inc(&(intf)->stats[IPMI_STAT_ ## stat])
645 #define ipmi_get_stat(intf, stat) \
646 	((unsigned int) atomic_read(&(intf)->stats[IPMI_STAT_ ## stat]))
647 
648 static const char * const addr_src_to_str[] = {
649 	"invalid", "hotmod", "hardcoded", "SPMI", "ACPI", "SMBIOS", "PCI",
650 	"device-tree", "platform"
651 };
652 
ipmi_addr_src_to_str(enum ipmi_addr_src src)653 const char *ipmi_addr_src_to_str(enum ipmi_addr_src src)
654 {
655 	if (src >= SI_LAST)
656 		src = 0; /* Invalid */
657 	return addr_src_to_str[src];
658 }
659 EXPORT_SYMBOL(ipmi_addr_src_to_str);
660 
is_lan_addr(struct ipmi_addr * addr)661 static int is_lan_addr(struct ipmi_addr *addr)
662 {
663 	return addr->addr_type == IPMI_LAN_ADDR_TYPE;
664 }
665 
is_ipmb_addr(struct ipmi_addr * addr)666 static int is_ipmb_addr(struct ipmi_addr *addr)
667 {
668 	return addr->addr_type == IPMI_IPMB_ADDR_TYPE;
669 }
670 
is_ipmb_bcast_addr(struct ipmi_addr * addr)671 static int is_ipmb_bcast_addr(struct ipmi_addr *addr)
672 {
673 	return addr->addr_type == IPMI_IPMB_BROADCAST_ADDR_TYPE;
674 }
675 
is_ipmb_direct_addr(struct ipmi_addr * addr)676 static int is_ipmb_direct_addr(struct ipmi_addr *addr)
677 {
678 	return addr->addr_type == IPMI_IPMB_DIRECT_ADDR_TYPE;
679 }
680 
free_recv_msg_list(struct list_head * q)681 static void free_recv_msg_list(struct list_head *q)
682 {
683 	struct ipmi_recv_msg *msg, *msg2;
684 
685 	list_for_each_entry_safe(msg, msg2, q, link) {
686 		list_del(&msg->link);
687 		ipmi_free_recv_msg(msg);
688 	}
689 }
690 
free_smi_msg_list(struct list_head * q)691 static void free_smi_msg_list(struct list_head *q)
692 {
693 	struct ipmi_smi_msg *msg, *msg2;
694 
695 	list_for_each_entry_safe(msg, msg2, q, link) {
696 		list_del(&msg->link);
697 		ipmi_free_smi_msg(msg);
698 	}
699 }
700 
clean_up_interface_data(struct ipmi_smi * intf)701 static void clean_up_interface_data(struct ipmi_smi *intf)
702 {
703 	int              i;
704 	struct cmd_rcvr  *rcvr, *rcvr2;
705 	struct list_head list;
706 
707 	tasklet_kill(&intf->recv_tasklet);
708 
709 	free_smi_msg_list(&intf->waiting_rcv_msgs);
710 	free_recv_msg_list(&intf->waiting_events);
711 
712 	/*
713 	 * Wholesale remove all the entries from the list in the
714 	 * interface and wait for RCU to know that none are in use.
715 	 */
716 	mutex_lock(&intf->cmd_rcvrs_mutex);
717 	INIT_LIST_HEAD(&list);
718 	list_splice_init_rcu(&intf->cmd_rcvrs, &list, synchronize_rcu);
719 	mutex_unlock(&intf->cmd_rcvrs_mutex);
720 
721 	list_for_each_entry_safe(rcvr, rcvr2, &list, link)
722 		kfree(rcvr);
723 
724 	for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) {
725 		if ((intf->seq_table[i].inuse)
726 					&& (intf->seq_table[i].recv_msg))
727 			ipmi_free_recv_msg(intf->seq_table[i].recv_msg);
728 	}
729 }
730 
intf_free(struct kref * ref)731 static void intf_free(struct kref *ref)
732 {
733 	struct ipmi_smi *intf = container_of(ref, struct ipmi_smi, refcount);
734 
735 	clean_up_interface_data(intf);
736 	kfree(intf);
737 }
738 
ipmi_smi_watcher_register(struct ipmi_smi_watcher * watcher)739 int ipmi_smi_watcher_register(struct ipmi_smi_watcher *watcher)
740 {
741 	struct ipmi_smi *intf;
742 	int index, rv;
743 
744 	/*
745 	 * Make sure the driver is actually initialized, this handles
746 	 * problems with initialization order.
747 	 */
748 	rv = ipmi_init_msghandler();
749 	if (rv)
750 		return rv;
751 
752 	mutex_lock(&smi_watchers_mutex);
753 
754 	list_add(&watcher->link, &smi_watchers);
755 
756 	index = srcu_read_lock(&ipmi_interfaces_srcu);
757 	list_for_each_entry_rcu(intf, &ipmi_interfaces, link,
758 			lockdep_is_held(&smi_watchers_mutex)) {
759 		int intf_num = READ_ONCE(intf->intf_num);
760 
761 		if (intf_num == -1)
762 			continue;
763 		watcher->new_smi(intf_num, intf->si_dev);
764 	}
765 	srcu_read_unlock(&ipmi_interfaces_srcu, index);
766 
767 	mutex_unlock(&smi_watchers_mutex);
768 
769 	return 0;
770 }
771 EXPORT_SYMBOL(ipmi_smi_watcher_register);
772 
ipmi_smi_watcher_unregister(struct ipmi_smi_watcher * watcher)773 int ipmi_smi_watcher_unregister(struct ipmi_smi_watcher *watcher)
774 {
775 	mutex_lock(&smi_watchers_mutex);
776 	list_del(&watcher->link);
777 	mutex_unlock(&smi_watchers_mutex);
778 	return 0;
779 }
780 EXPORT_SYMBOL(ipmi_smi_watcher_unregister);
781 
782 /*
783  * Must be called with smi_watchers_mutex held.
784  */
785 static void
call_smi_watchers(int i,struct device * dev)786 call_smi_watchers(int i, struct device *dev)
787 {
788 	struct ipmi_smi_watcher *w;
789 
790 	mutex_lock(&smi_watchers_mutex);
791 	list_for_each_entry(w, &smi_watchers, link) {
792 		if (try_module_get(w->owner)) {
793 			w->new_smi(i, dev);
794 			module_put(w->owner);
795 		}
796 	}
797 	mutex_unlock(&smi_watchers_mutex);
798 }
799 
800 static int
ipmi_addr_equal(struct ipmi_addr * addr1,struct ipmi_addr * addr2)801 ipmi_addr_equal(struct ipmi_addr *addr1, struct ipmi_addr *addr2)
802 {
803 	if (addr1->addr_type != addr2->addr_type)
804 		return 0;
805 
806 	if (addr1->channel != addr2->channel)
807 		return 0;
808 
809 	if (addr1->addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE) {
810 		struct ipmi_system_interface_addr *smi_addr1
811 		    = (struct ipmi_system_interface_addr *) addr1;
812 		struct ipmi_system_interface_addr *smi_addr2
813 		    = (struct ipmi_system_interface_addr *) addr2;
814 		return (smi_addr1->lun == smi_addr2->lun);
815 	}
816 
817 	if (is_ipmb_addr(addr1) || is_ipmb_bcast_addr(addr1)) {
818 		struct ipmi_ipmb_addr *ipmb_addr1
819 		    = (struct ipmi_ipmb_addr *) addr1;
820 		struct ipmi_ipmb_addr *ipmb_addr2
821 		    = (struct ipmi_ipmb_addr *) addr2;
822 
823 		return ((ipmb_addr1->slave_addr == ipmb_addr2->slave_addr)
824 			&& (ipmb_addr1->lun == ipmb_addr2->lun));
825 	}
826 
827 	if (is_ipmb_direct_addr(addr1)) {
828 		struct ipmi_ipmb_direct_addr *daddr1
829 			= (struct ipmi_ipmb_direct_addr *) addr1;
830 		struct ipmi_ipmb_direct_addr *daddr2
831 			= (struct ipmi_ipmb_direct_addr *) addr2;
832 
833 		return daddr1->slave_addr == daddr2->slave_addr &&
834 			daddr1->rq_lun == daddr2->rq_lun &&
835 			daddr1->rs_lun == daddr2->rs_lun;
836 	}
837 
838 	if (is_lan_addr(addr1)) {
839 		struct ipmi_lan_addr *lan_addr1
840 			= (struct ipmi_lan_addr *) addr1;
841 		struct ipmi_lan_addr *lan_addr2
842 		    = (struct ipmi_lan_addr *) addr2;
843 
844 		return ((lan_addr1->remote_SWID == lan_addr2->remote_SWID)
845 			&& (lan_addr1->local_SWID == lan_addr2->local_SWID)
846 			&& (lan_addr1->session_handle
847 			    == lan_addr2->session_handle)
848 			&& (lan_addr1->lun == lan_addr2->lun));
849 	}
850 
851 	return 1;
852 }
853 
ipmi_validate_addr(struct ipmi_addr * addr,int len)854 int ipmi_validate_addr(struct ipmi_addr *addr, int len)
855 {
856 	if (len < sizeof(struct ipmi_system_interface_addr))
857 		return -EINVAL;
858 
859 	if (addr->addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE) {
860 		if (addr->channel != IPMI_BMC_CHANNEL)
861 			return -EINVAL;
862 		return 0;
863 	}
864 
865 	if ((addr->channel == IPMI_BMC_CHANNEL)
866 	    || (addr->channel >= IPMI_MAX_CHANNELS)
867 	    || (addr->channel < 0))
868 		return -EINVAL;
869 
870 	if (is_ipmb_addr(addr) || is_ipmb_bcast_addr(addr)) {
871 		if (len < sizeof(struct ipmi_ipmb_addr))
872 			return -EINVAL;
873 		return 0;
874 	}
875 
876 	if (is_ipmb_direct_addr(addr)) {
877 		struct ipmi_ipmb_direct_addr *daddr = (void *) addr;
878 
879 		if (addr->channel != 0)
880 			return -EINVAL;
881 		if (len < sizeof(struct ipmi_ipmb_direct_addr))
882 			return -EINVAL;
883 
884 		if (daddr->slave_addr & 0x01)
885 			return -EINVAL;
886 		if (daddr->rq_lun >= 4)
887 			return -EINVAL;
888 		if (daddr->rs_lun >= 4)
889 			return -EINVAL;
890 		return 0;
891 	}
892 
893 	if (is_lan_addr(addr)) {
894 		if (len < sizeof(struct ipmi_lan_addr))
895 			return -EINVAL;
896 		return 0;
897 	}
898 
899 	return -EINVAL;
900 }
901 EXPORT_SYMBOL(ipmi_validate_addr);
902 
ipmi_addr_length(int addr_type)903 unsigned int ipmi_addr_length(int addr_type)
904 {
905 	if (addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
906 		return sizeof(struct ipmi_system_interface_addr);
907 
908 	if ((addr_type == IPMI_IPMB_ADDR_TYPE)
909 			|| (addr_type == IPMI_IPMB_BROADCAST_ADDR_TYPE))
910 		return sizeof(struct ipmi_ipmb_addr);
911 
912 	if (addr_type == IPMI_IPMB_DIRECT_ADDR_TYPE)
913 		return sizeof(struct ipmi_ipmb_direct_addr);
914 
915 	if (addr_type == IPMI_LAN_ADDR_TYPE)
916 		return sizeof(struct ipmi_lan_addr);
917 
918 	return 0;
919 }
920 EXPORT_SYMBOL(ipmi_addr_length);
921 
deliver_response(struct ipmi_smi * intf,struct ipmi_recv_msg * msg)922 static int deliver_response(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
923 {
924 	int rv = 0;
925 
926 	if (!msg->user) {
927 		/* Special handling for NULL users. */
928 		if (intf->null_user_handler) {
929 			intf->null_user_handler(intf, msg);
930 		} else {
931 			/* No handler, so give up. */
932 			rv = -EINVAL;
933 		}
934 		ipmi_free_recv_msg(msg);
935 	} else if (oops_in_progress) {
936 		/*
937 		 * If we are running in the panic context, calling the
938 		 * receive handler doesn't much meaning and has a deadlock
939 		 * risk.  At this moment, simply skip it in that case.
940 		 */
941 		ipmi_free_recv_msg(msg);
942 		atomic_dec(&msg->user->nr_msgs);
943 	} else {
944 		int index;
945 		struct ipmi_user *user = acquire_ipmi_user(msg->user, &index);
946 
947 		if (user) {
948 			atomic_dec(&user->nr_msgs);
949 			user->handler->ipmi_recv_hndl(msg, user->handler_data);
950 			release_ipmi_user(user, index);
951 		} else {
952 			/* User went away, give up. */
953 			ipmi_free_recv_msg(msg);
954 			rv = -EINVAL;
955 		}
956 	}
957 
958 	return rv;
959 }
960 
deliver_local_response(struct ipmi_smi * intf,struct ipmi_recv_msg * msg)961 static void deliver_local_response(struct ipmi_smi *intf,
962 				   struct ipmi_recv_msg *msg)
963 {
964 	if (deliver_response(intf, msg))
965 		ipmi_inc_stat(intf, unhandled_local_responses);
966 	else
967 		ipmi_inc_stat(intf, handled_local_responses);
968 }
969 
deliver_err_response(struct ipmi_smi * intf,struct ipmi_recv_msg * msg,int err)970 static void deliver_err_response(struct ipmi_smi *intf,
971 				 struct ipmi_recv_msg *msg, int err)
972 {
973 	msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
974 	msg->msg_data[0] = err;
975 	msg->msg.netfn |= 1; /* Convert to a response. */
976 	msg->msg.data_len = 1;
977 	msg->msg.data = msg->msg_data;
978 	deliver_local_response(intf, msg);
979 }
980 
smi_add_watch(struct ipmi_smi * intf,unsigned int flags)981 static void smi_add_watch(struct ipmi_smi *intf, unsigned int flags)
982 {
983 	unsigned long iflags;
984 
985 	if (!intf->handlers->set_need_watch)
986 		return;
987 
988 	spin_lock_irqsave(&intf->watch_lock, iflags);
989 	if (flags & IPMI_WATCH_MASK_CHECK_MESSAGES)
990 		intf->response_waiters++;
991 
992 	if (flags & IPMI_WATCH_MASK_CHECK_WATCHDOG)
993 		intf->watchdog_waiters++;
994 
995 	if (flags & IPMI_WATCH_MASK_CHECK_COMMANDS)
996 		intf->command_waiters++;
997 
998 	if ((intf->last_watch_mask & flags) != flags) {
999 		intf->last_watch_mask |= flags;
1000 		intf->handlers->set_need_watch(intf->send_info,
1001 					       intf->last_watch_mask);
1002 	}
1003 	spin_unlock_irqrestore(&intf->watch_lock, iflags);
1004 }
1005 
smi_remove_watch(struct ipmi_smi * intf,unsigned int flags)1006 static void smi_remove_watch(struct ipmi_smi *intf, unsigned int flags)
1007 {
1008 	unsigned long iflags;
1009 
1010 	if (!intf->handlers->set_need_watch)
1011 		return;
1012 
1013 	spin_lock_irqsave(&intf->watch_lock, iflags);
1014 	if (flags & IPMI_WATCH_MASK_CHECK_MESSAGES)
1015 		intf->response_waiters--;
1016 
1017 	if (flags & IPMI_WATCH_MASK_CHECK_WATCHDOG)
1018 		intf->watchdog_waiters--;
1019 
1020 	if (flags & IPMI_WATCH_MASK_CHECK_COMMANDS)
1021 		intf->command_waiters--;
1022 
1023 	flags = 0;
1024 	if (intf->response_waiters)
1025 		flags |= IPMI_WATCH_MASK_CHECK_MESSAGES;
1026 	if (intf->watchdog_waiters)
1027 		flags |= IPMI_WATCH_MASK_CHECK_WATCHDOG;
1028 	if (intf->command_waiters)
1029 		flags |= IPMI_WATCH_MASK_CHECK_COMMANDS;
1030 
1031 	if (intf->last_watch_mask != flags) {
1032 		intf->last_watch_mask = flags;
1033 		intf->handlers->set_need_watch(intf->send_info,
1034 					       intf->last_watch_mask);
1035 	}
1036 	spin_unlock_irqrestore(&intf->watch_lock, iflags);
1037 }
1038 
1039 /*
1040  * Find the next sequence number not being used and add the given
1041  * message with the given timeout to the sequence table.  This must be
1042  * called with the interface's seq_lock held.
1043  */
intf_next_seq(struct ipmi_smi * intf,struct ipmi_recv_msg * recv_msg,unsigned long timeout,int retries,int broadcast,unsigned char * seq,long * seqid)1044 static int intf_next_seq(struct ipmi_smi      *intf,
1045 			 struct ipmi_recv_msg *recv_msg,
1046 			 unsigned long        timeout,
1047 			 int                  retries,
1048 			 int                  broadcast,
1049 			 unsigned char        *seq,
1050 			 long                 *seqid)
1051 {
1052 	int          rv = 0;
1053 	unsigned int i;
1054 
1055 	if (timeout == 0)
1056 		timeout = default_retry_ms;
1057 	if (retries < 0)
1058 		retries = default_max_retries;
1059 
1060 	for (i = intf->curr_seq; (i+1)%IPMI_IPMB_NUM_SEQ != intf->curr_seq;
1061 					i = (i+1)%IPMI_IPMB_NUM_SEQ) {
1062 		if (!intf->seq_table[i].inuse)
1063 			break;
1064 	}
1065 
1066 	if (!intf->seq_table[i].inuse) {
1067 		intf->seq_table[i].recv_msg = recv_msg;
1068 
1069 		/*
1070 		 * Start with the maximum timeout, when the send response
1071 		 * comes in we will start the real timer.
1072 		 */
1073 		intf->seq_table[i].timeout = MAX_MSG_TIMEOUT;
1074 		intf->seq_table[i].orig_timeout = timeout;
1075 		intf->seq_table[i].retries_left = retries;
1076 		intf->seq_table[i].broadcast = broadcast;
1077 		intf->seq_table[i].inuse = 1;
1078 		intf->seq_table[i].seqid = NEXT_SEQID(intf->seq_table[i].seqid);
1079 		*seq = i;
1080 		*seqid = intf->seq_table[i].seqid;
1081 		intf->curr_seq = (i+1)%IPMI_IPMB_NUM_SEQ;
1082 		smi_add_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES);
1083 		need_waiter(intf);
1084 	} else {
1085 		rv = -EAGAIN;
1086 	}
1087 
1088 	return rv;
1089 }
1090 
1091 /*
1092  * Return the receive message for the given sequence number and
1093  * release the sequence number so it can be reused.  Some other data
1094  * is passed in to be sure the message matches up correctly (to help
1095  * guard against message coming in after their timeout and the
1096  * sequence number being reused).
1097  */
intf_find_seq(struct ipmi_smi * intf,unsigned char seq,short channel,unsigned char cmd,unsigned char netfn,struct ipmi_addr * addr,struct ipmi_recv_msg ** recv_msg)1098 static int intf_find_seq(struct ipmi_smi      *intf,
1099 			 unsigned char        seq,
1100 			 short                channel,
1101 			 unsigned char        cmd,
1102 			 unsigned char        netfn,
1103 			 struct ipmi_addr     *addr,
1104 			 struct ipmi_recv_msg **recv_msg)
1105 {
1106 	int           rv = -ENODEV;
1107 	unsigned long flags;
1108 
1109 	if (seq >= IPMI_IPMB_NUM_SEQ)
1110 		return -EINVAL;
1111 
1112 	spin_lock_irqsave(&intf->seq_lock, flags);
1113 	if (intf->seq_table[seq].inuse) {
1114 		struct ipmi_recv_msg *msg = intf->seq_table[seq].recv_msg;
1115 
1116 		if ((msg->addr.channel == channel) && (msg->msg.cmd == cmd)
1117 				&& (msg->msg.netfn == netfn)
1118 				&& (ipmi_addr_equal(addr, &msg->addr))) {
1119 			*recv_msg = msg;
1120 			intf->seq_table[seq].inuse = 0;
1121 			smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES);
1122 			rv = 0;
1123 		}
1124 	}
1125 	spin_unlock_irqrestore(&intf->seq_lock, flags);
1126 
1127 	return rv;
1128 }
1129 
1130 
1131 /* Start the timer for a specific sequence table entry. */
intf_start_seq_timer(struct ipmi_smi * intf,long msgid)1132 static int intf_start_seq_timer(struct ipmi_smi *intf,
1133 				long       msgid)
1134 {
1135 	int           rv = -ENODEV;
1136 	unsigned long flags;
1137 	unsigned char seq;
1138 	unsigned long seqid;
1139 
1140 
1141 	GET_SEQ_FROM_MSGID(msgid, seq, seqid);
1142 
1143 	spin_lock_irqsave(&intf->seq_lock, flags);
1144 	/*
1145 	 * We do this verification because the user can be deleted
1146 	 * while a message is outstanding.
1147 	 */
1148 	if ((intf->seq_table[seq].inuse)
1149 				&& (intf->seq_table[seq].seqid == seqid)) {
1150 		struct seq_table *ent = &intf->seq_table[seq];
1151 		ent->timeout = ent->orig_timeout;
1152 		rv = 0;
1153 	}
1154 	spin_unlock_irqrestore(&intf->seq_lock, flags);
1155 
1156 	return rv;
1157 }
1158 
1159 /* Got an error for the send message for a specific sequence number. */
intf_err_seq(struct ipmi_smi * intf,long msgid,unsigned int err)1160 static int intf_err_seq(struct ipmi_smi *intf,
1161 			long         msgid,
1162 			unsigned int err)
1163 {
1164 	int                  rv = -ENODEV;
1165 	unsigned long        flags;
1166 	unsigned char        seq;
1167 	unsigned long        seqid;
1168 	struct ipmi_recv_msg *msg = NULL;
1169 
1170 
1171 	GET_SEQ_FROM_MSGID(msgid, seq, seqid);
1172 
1173 	spin_lock_irqsave(&intf->seq_lock, flags);
1174 	/*
1175 	 * We do this verification because the user can be deleted
1176 	 * while a message is outstanding.
1177 	 */
1178 	if ((intf->seq_table[seq].inuse)
1179 				&& (intf->seq_table[seq].seqid == seqid)) {
1180 		struct seq_table *ent = &intf->seq_table[seq];
1181 
1182 		ent->inuse = 0;
1183 		smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES);
1184 		msg = ent->recv_msg;
1185 		rv = 0;
1186 	}
1187 	spin_unlock_irqrestore(&intf->seq_lock, flags);
1188 
1189 	if (msg)
1190 		deliver_err_response(intf, msg, err);
1191 
1192 	return rv;
1193 }
1194 
free_user_work(struct work_struct * work)1195 static void free_user_work(struct work_struct *work)
1196 {
1197 	struct ipmi_user *user = container_of(work, struct ipmi_user,
1198 					      remove_work);
1199 
1200 	cleanup_srcu_struct(&user->release_barrier);
1201 	vfree(user);
1202 }
1203 
ipmi_create_user(unsigned int if_num,const struct ipmi_user_hndl * handler,void * handler_data,struct ipmi_user ** user)1204 int ipmi_create_user(unsigned int          if_num,
1205 		     const struct ipmi_user_hndl *handler,
1206 		     void                  *handler_data,
1207 		     struct ipmi_user      **user)
1208 {
1209 	unsigned long flags;
1210 	struct ipmi_user *new_user;
1211 	int           rv, index;
1212 	struct ipmi_smi *intf;
1213 
1214 	/*
1215 	 * There is no module usecount here, because it's not
1216 	 * required.  Since this can only be used by and called from
1217 	 * other modules, they will implicitly use this module, and
1218 	 * thus this can't be removed unless the other modules are
1219 	 * removed.
1220 	 */
1221 
1222 	if (handler == NULL)
1223 		return -EINVAL;
1224 
1225 	/*
1226 	 * Make sure the driver is actually initialized, this handles
1227 	 * problems with initialization order.
1228 	 */
1229 	rv = ipmi_init_msghandler();
1230 	if (rv)
1231 		return rv;
1232 
1233 	new_user = vzalloc(sizeof(*new_user));
1234 	if (!new_user)
1235 		return -ENOMEM;
1236 
1237 	index = srcu_read_lock(&ipmi_interfaces_srcu);
1238 	list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
1239 		if (intf->intf_num == if_num)
1240 			goto found;
1241 	}
1242 	/* Not found, return an error */
1243 	rv = -EINVAL;
1244 	goto out_kfree;
1245 
1246  found:
1247 	if (atomic_add_return(1, &intf->nr_users) > max_users) {
1248 		rv = -EBUSY;
1249 		goto out_kfree;
1250 	}
1251 
1252 	INIT_WORK(&new_user->remove_work, free_user_work);
1253 
1254 	rv = init_srcu_struct(&new_user->release_barrier);
1255 	if (rv)
1256 		goto out_kfree;
1257 
1258 	if (!try_module_get(intf->owner)) {
1259 		rv = -ENODEV;
1260 		goto out_kfree;
1261 	}
1262 
1263 	/* Note that each existing user holds a refcount to the interface. */
1264 	kref_get(&intf->refcount);
1265 
1266 	atomic_set(&new_user->nr_msgs, 0);
1267 	kref_init(&new_user->refcount);
1268 	new_user->handler = handler;
1269 	new_user->handler_data = handler_data;
1270 	new_user->intf = intf;
1271 	new_user->gets_events = false;
1272 
1273 	rcu_assign_pointer(new_user->self, new_user);
1274 	spin_lock_irqsave(&intf->seq_lock, flags);
1275 	list_add_rcu(&new_user->link, &intf->users);
1276 	spin_unlock_irqrestore(&intf->seq_lock, flags);
1277 	if (handler->ipmi_watchdog_pretimeout)
1278 		/* User wants pretimeouts, so make sure to watch for them. */
1279 		smi_add_watch(intf, IPMI_WATCH_MASK_CHECK_WATCHDOG);
1280 	srcu_read_unlock(&ipmi_interfaces_srcu, index);
1281 	*user = new_user;
1282 	return 0;
1283 
1284 out_kfree:
1285 	atomic_dec(&intf->nr_users);
1286 	srcu_read_unlock(&ipmi_interfaces_srcu, index);
1287 	vfree(new_user);
1288 	return rv;
1289 }
1290 EXPORT_SYMBOL(ipmi_create_user);
1291 
ipmi_get_smi_info(int if_num,struct ipmi_smi_info * data)1292 int ipmi_get_smi_info(int if_num, struct ipmi_smi_info *data)
1293 {
1294 	int rv, index;
1295 	struct ipmi_smi *intf;
1296 
1297 	index = srcu_read_lock(&ipmi_interfaces_srcu);
1298 	list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
1299 		if (intf->intf_num == if_num)
1300 			goto found;
1301 	}
1302 	srcu_read_unlock(&ipmi_interfaces_srcu, index);
1303 
1304 	/* Not found, return an error */
1305 	return -EINVAL;
1306 
1307 found:
1308 	if (!intf->handlers->get_smi_info)
1309 		rv = -ENOTTY;
1310 	else
1311 		rv = intf->handlers->get_smi_info(intf->send_info, data);
1312 	srcu_read_unlock(&ipmi_interfaces_srcu, index);
1313 
1314 	return rv;
1315 }
1316 EXPORT_SYMBOL(ipmi_get_smi_info);
1317 
free_user(struct kref * ref)1318 static void free_user(struct kref *ref)
1319 {
1320 	struct ipmi_user *user = container_of(ref, struct ipmi_user, refcount);
1321 
1322 	/* SRCU cleanup must happen in task context. */
1323 	queue_work(remove_work_wq, &user->remove_work);
1324 }
1325 
_ipmi_destroy_user(struct ipmi_user * user)1326 static void _ipmi_destroy_user(struct ipmi_user *user)
1327 {
1328 	struct ipmi_smi  *intf = user->intf;
1329 	int              i;
1330 	unsigned long    flags;
1331 	struct cmd_rcvr  *rcvr;
1332 	struct cmd_rcvr  *rcvrs = NULL;
1333 	struct module    *owner;
1334 
1335 	if (!acquire_ipmi_user(user, &i)) {
1336 		/*
1337 		 * The user has already been cleaned up, just make sure
1338 		 * nothing is using it and return.
1339 		 */
1340 		synchronize_srcu(&user->release_barrier);
1341 		return;
1342 	}
1343 
1344 	rcu_assign_pointer(user->self, NULL);
1345 	release_ipmi_user(user, i);
1346 
1347 	synchronize_srcu(&user->release_barrier);
1348 
1349 	if (user->handler->shutdown)
1350 		user->handler->shutdown(user->handler_data);
1351 
1352 	if (user->handler->ipmi_watchdog_pretimeout)
1353 		smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_WATCHDOG);
1354 
1355 	if (user->gets_events)
1356 		atomic_dec(&intf->event_waiters);
1357 
1358 	/* Remove the user from the interface's sequence table. */
1359 	spin_lock_irqsave(&intf->seq_lock, flags);
1360 	list_del_rcu(&user->link);
1361 	atomic_dec(&intf->nr_users);
1362 
1363 	for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) {
1364 		if (intf->seq_table[i].inuse
1365 		    && (intf->seq_table[i].recv_msg->user == user)) {
1366 			intf->seq_table[i].inuse = 0;
1367 			smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES);
1368 			ipmi_free_recv_msg(intf->seq_table[i].recv_msg);
1369 		}
1370 	}
1371 	spin_unlock_irqrestore(&intf->seq_lock, flags);
1372 
1373 	/*
1374 	 * Remove the user from the command receiver's table.  First
1375 	 * we build a list of everything (not using the standard link,
1376 	 * since other things may be using it till we do
1377 	 * synchronize_srcu()) then free everything in that list.
1378 	 */
1379 	mutex_lock(&intf->cmd_rcvrs_mutex);
1380 	list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link,
1381 				lockdep_is_held(&intf->cmd_rcvrs_mutex)) {
1382 		if (rcvr->user == user) {
1383 			list_del_rcu(&rcvr->link);
1384 			rcvr->next = rcvrs;
1385 			rcvrs = rcvr;
1386 		}
1387 	}
1388 	mutex_unlock(&intf->cmd_rcvrs_mutex);
1389 	synchronize_rcu();
1390 	while (rcvrs) {
1391 		rcvr = rcvrs;
1392 		rcvrs = rcvr->next;
1393 		kfree(rcvr);
1394 	}
1395 
1396 	owner = intf->owner;
1397 	kref_put(&intf->refcount, intf_free);
1398 	module_put(owner);
1399 }
1400 
ipmi_destroy_user(struct ipmi_user * user)1401 int ipmi_destroy_user(struct ipmi_user *user)
1402 {
1403 	_ipmi_destroy_user(user);
1404 
1405 	kref_put(&user->refcount, free_user);
1406 
1407 	return 0;
1408 }
1409 EXPORT_SYMBOL(ipmi_destroy_user);
1410 
ipmi_get_version(struct ipmi_user * user,unsigned char * major,unsigned char * minor)1411 int ipmi_get_version(struct ipmi_user *user,
1412 		     unsigned char *major,
1413 		     unsigned char *minor)
1414 {
1415 	struct ipmi_device_id id;
1416 	int rv, index;
1417 
1418 	user = acquire_ipmi_user(user, &index);
1419 	if (!user)
1420 		return -ENODEV;
1421 
1422 	rv = bmc_get_device_id(user->intf, NULL, &id, NULL, NULL);
1423 	if (!rv) {
1424 		*major = ipmi_version_major(&id);
1425 		*minor = ipmi_version_minor(&id);
1426 	}
1427 	release_ipmi_user(user, index);
1428 
1429 	return rv;
1430 }
1431 EXPORT_SYMBOL(ipmi_get_version);
1432 
ipmi_set_my_address(struct ipmi_user * user,unsigned int channel,unsigned char address)1433 int ipmi_set_my_address(struct ipmi_user *user,
1434 			unsigned int  channel,
1435 			unsigned char address)
1436 {
1437 	int index, rv = 0;
1438 
1439 	user = acquire_ipmi_user(user, &index);
1440 	if (!user)
1441 		return -ENODEV;
1442 
1443 	if (channel >= IPMI_MAX_CHANNELS) {
1444 		rv = -EINVAL;
1445 	} else {
1446 		channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
1447 		user->intf->addrinfo[channel].address = address;
1448 	}
1449 	release_ipmi_user(user, index);
1450 
1451 	return rv;
1452 }
1453 EXPORT_SYMBOL(ipmi_set_my_address);
1454 
ipmi_get_my_address(struct ipmi_user * user,unsigned int channel,unsigned char * address)1455 int ipmi_get_my_address(struct ipmi_user *user,
1456 			unsigned int  channel,
1457 			unsigned char *address)
1458 {
1459 	int index, rv = 0;
1460 
1461 	user = acquire_ipmi_user(user, &index);
1462 	if (!user)
1463 		return -ENODEV;
1464 
1465 	if (channel >= IPMI_MAX_CHANNELS) {
1466 		rv = -EINVAL;
1467 	} else {
1468 		channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
1469 		*address = user->intf->addrinfo[channel].address;
1470 	}
1471 	release_ipmi_user(user, index);
1472 
1473 	return rv;
1474 }
1475 EXPORT_SYMBOL(ipmi_get_my_address);
1476 
ipmi_set_my_LUN(struct ipmi_user * user,unsigned int channel,unsigned char LUN)1477 int ipmi_set_my_LUN(struct ipmi_user *user,
1478 		    unsigned int  channel,
1479 		    unsigned char LUN)
1480 {
1481 	int index, rv = 0;
1482 
1483 	user = acquire_ipmi_user(user, &index);
1484 	if (!user)
1485 		return -ENODEV;
1486 
1487 	if (channel >= IPMI_MAX_CHANNELS) {
1488 		rv = -EINVAL;
1489 	} else {
1490 		channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
1491 		user->intf->addrinfo[channel].lun = LUN & 0x3;
1492 	}
1493 	release_ipmi_user(user, index);
1494 
1495 	return rv;
1496 }
1497 EXPORT_SYMBOL(ipmi_set_my_LUN);
1498 
ipmi_get_my_LUN(struct ipmi_user * user,unsigned int channel,unsigned char * address)1499 int ipmi_get_my_LUN(struct ipmi_user *user,
1500 		    unsigned int  channel,
1501 		    unsigned char *address)
1502 {
1503 	int index, rv = 0;
1504 
1505 	user = acquire_ipmi_user(user, &index);
1506 	if (!user)
1507 		return -ENODEV;
1508 
1509 	if (channel >= IPMI_MAX_CHANNELS) {
1510 		rv = -EINVAL;
1511 	} else {
1512 		channel = array_index_nospec(channel, IPMI_MAX_CHANNELS);
1513 		*address = user->intf->addrinfo[channel].lun;
1514 	}
1515 	release_ipmi_user(user, index);
1516 
1517 	return rv;
1518 }
1519 EXPORT_SYMBOL(ipmi_get_my_LUN);
1520 
ipmi_get_maintenance_mode(struct ipmi_user * user)1521 int ipmi_get_maintenance_mode(struct ipmi_user *user)
1522 {
1523 	int mode, index;
1524 	unsigned long flags;
1525 
1526 	user = acquire_ipmi_user(user, &index);
1527 	if (!user)
1528 		return -ENODEV;
1529 
1530 	spin_lock_irqsave(&user->intf->maintenance_mode_lock, flags);
1531 	mode = user->intf->maintenance_mode;
1532 	spin_unlock_irqrestore(&user->intf->maintenance_mode_lock, flags);
1533 	release_ipmi_user(user, index);
1534 
1535 	return mode;
1536 }
1537 EXPORT_SYMBOL(ipmi_get_maintenance_mode);
1538 
maintenance_mode_update(struct ipmi_smi * intf)1539 static void maintenance_mode_update(struct ipmi_smi *intf)
1540 {
1541 	if (intf->handlers->set_maintenance_mode)
1542 		intf->handlers->set_maintenance_mode(
1543 			intf->send_info, intf->maintenance_mode_enable);
1544 }
1545 
ipmi_set_maintenance_mode(struct ipmi_user * user,int mode)1546 int ipmi_set_maintenance_mode(struct ipmi_user *user, int mode)
1547 {
1548 	int rv = 0, index;
1549 	unsigned long flags;
1550 	struct ipmi_smi *intf = user->intf;
1551 
1552 	user = acquire_ipmi_user(user, &index);
1553 	if (!user)
1554 		return -ENODEV;
1555 
1556 	spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
1557 	if (intf->maintenance_mode != mode) {
1558 		switch (mode) {
1559 		case IPMI_MAINTENANCE_MODE_AUTO:
1560 			intf->maintenance_mode_enable
1561 				= (intf->auto_maintenance_timeout > 0);
1562 			break;
1563 
1564 		case IPMI_MAINTENANCE_MODE_OFF:
1565 			intf->maintenance_mode_enable = false;
1566 			break;
1567 
1568 		case IPMI_MAINTENANCE_MODE_ON:
1569 			intf->maintenance_mode_enable = true;
1570 			break;
1571 
1572 		default:
1573 			rv = -EINVAL;
1574 			goto out_unlock;
1575 		}
1576 		intf->maintenance_mode = mode;
1577 
1578 		maintenance_mode_update(intf);
1579 	}
1580  out_unlock:
1581 	spin_unlock_irqrestore(&intf->maintenance_mode_lock, flags);
1582 	release_ipmi_user(user, index);
1583 
1584 	return rv;
1585 }
1586 EXPORT_SYMBOL(ipmi_set_maintenance_mode);
1587 
ipmi_set_gets_events(struct ipmi_user * user,bool val)1588 int ipmi_set_gets_events(struct ipmi_user *user, bool val)
1589 {
1590 	unsigned long        flags;
1591 	struct ipmi_smi      *intf = user->intf;
1592 	struct ipmi_recv_msg *msg, *msg2;
1593 	struct list_head     msgs;
1594 	int index;
1595 
1596 	user = acquire_ipmi_user(user, &index);
1597 	if (!user)
1598 		return -ENODEV;
1599 
1600 	INIT_LIST_HEAD(&msgs);
1601 
1602 	spin_lock_irqsave(&intf->events_lock, flags);
1603 	if (user->gets_events == val)
1604 		goto out;
1605 
1606 	user->gets_events = val;
1607 
1608 	if (val) {
1609 		if (atomic_inc_return(&intf->event_waiters) == 1)
1610 			need_waiter(intf);
1611 	} else {
1612 		atomic_dec(&intf->event_waiters);
1613 	}
1614 
1615 	if (intf->delivering_events)
1616 		/*
1617 		 * Another thread is delivering events for this, so
1618 		 * let it handle any new events.
1619 		 */
1620 		goto out;
1621 
1622 	/* Deliver any queued events. */
1623 	while (user->gets_events && !list_empty(&intf->waiting_events)) {
1624 		list_for_each_entry_safe(msg, msg2, &intf->waiting_events, link)
1625 			list_move_tail(&msg->link, &msgs);
1626 		intf->waiting_events_count = 0;
1627 		if (intf->event_msg_printed) {
1628 			dev_warn(intf->si_dev, "Event queue no longer full\n");
1629 			intf->event_msg_printed = 0;
1630 		}
1631 
1632 		intf->delivering_events = 1;
1633 		spin_unlock_irqrestore(&intf->events_lock, flags);
1634 
1635 		list_for_each_entry_safe(msg, msg2, &msgs, link) {
1636 			msg->user = user;
1637 			kref_get(&user->refcount);
1638 			deliver_local_response(intf, msg);
1639 		}
1640 
1641 		spin_lock_irqsave(&intf->events_lock, flags);
1642 		intf->delivering_events = 0;
1643 	}
1644 
1645  out:
1646 	spin_unlock_irqrestore(&intf->events_lock, flags);
1647 	release_ipmi_user(user, index);
1648 
1649 	return 0;
1650 }
1651 EXPORT_SYMBOL(ipmi_set_gets_events);
1652 
find_cmd_rcvr(struct ipmi_smi * intf,unsigned char netfn,unsigned char cmd,unsigned char chan)1653 static struct cmd_rcvr *find_cmd_rcvr(struct ipmi_smi *intf,
1654 				      unsigned char netfn,
1655 				      unsigned char cmd,
1656 				      unsigned char chan)
1657 {
1658 	struct cmd_rcvr *rcvr;
1659 
1660 	list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link,
1661 				lockdep_is_held(&intf->cmd_rcvrs_mutex)) {
1662 		if ((rcvr->netfn == netfn) && (rcvr->cmd == cmd)
1663 					&& (rcvr->chans & (1 << chan)))
1664 			return rcvr;
1665 	}
1666 	return NULL;
1667 }
1668 
is_cmd_rcvr_exclusive(struct ipmi_smi * intf,unsigned char netfn,unsigned char cmd,unsigned int chans)1669 static int is_cmd_rcvr_exclusive(struct ipmi_smi *intf,
1670 				 unsigned char netfn,
1671 				 unsigned char cmd,
1672 				 unsigned int  chans)
1673 {
1674 	struct cmd_rcvr *rcvr;
1675 
1676 	list_for_each_entry_rcu(rcvr, &intf->cmd_rcvrs, link,
1677 				lockdep_is_held(&intf->cmd_rcvrs_mutex)) {
1678 		if ((rcvr->netfn == netfn) && (rcvr->cmd == cmd)
1679 					&& (rcvr->chans & chans))
1680 			return 0;
1681 	}
1682 	return 1;
1683 }
1684 
ipmi_register_for_cmd(struct ipmi_user * user,unsigned char netfn,unsigned char cmd,unsigned int chans)1685 int ipmi_register_for_cmd(struct ipmi_user *user,
1686 			  unsigned char netfn,
1687 			  unsigned char cmd,
1688 			  unsigned int  chans)
1689 {
1690 	struct ipmi_smi *intf = user->intf;
1691 	struct cmd_rcvr *rcvr;
1692 	int rv = 0, index;
1693 
1694 	user = acquire_ipmi_user(user, &index);
1695 	if (!user)
1696 		return -ENODEV;
1697 
1698 	rcvr = kmalloc(sizeof(*rcvr), GFP_KERNEL);
1699 	if (!rcvr) {
1700 		rv = -ENOMEM;
1701 		goto out_release;
1702 	}
1703 	rcvr->cmd = cmd;
1704 	rcvr->netfn = netfn;
1705 	rcvr->chans = chans;
1706 	rcvr->user = user;
1707 
1708 	mutex_lock(&intf->cmd_rcvrs_mutex);
1709 	/* Make sure the command/netfn is not already registered. */
1710 	if (!is_cmd_rcvr_exclusive(intf, netfn, cmd, chans)) {
1711 		rv = -EBUSY;
1712 		goto out_unlock;
1713 	}
1714 
1715 	smi_add_watch(intf, IPMI_WATCH_MASK_CHECK_COMMANDS);
1716 
1717 	list_add_rcu(&rcvr->link, &intf->cmd_rcvrs);
1718 
1719 out_unlock:
1720 	mutex_unlock(&intf->cmd_rcvrs_mutex);
1721 	if (rv)
1722 		kfree(rcvr);
1723 out_release:
1724 	release_ipmi_user(user, index);
1725 
1726 	return rv;
1727 }
1728 EXPORT_SYMBOL(ipmi_register_for_cmd);
1729 
ipmi_unregister_for_cmd(struct ipmi_user * user,unsigned char netfn,unsigned char cmd,unsigned int chans)1730 int ipmi_unregister_for_cmd(struct ipmi_user *user,
1731 			    unsigned char netfn,
1732 			    unsigned char cmd,
1733 			    unsigned int  chans)
1734 {
1735 	struct ipmi_smi *intf = user->intf;
1736 	struct cmd_rcvr *rcvr;
1737 	struct cmd_rcvr *rcvrs = NULL;
1738 	int i, rv = -ENOENT, index;
1739 
1740 	user = acquire_ipmi_user(user, &index);
1741 	if (!user)
1742 		return -ENODEV;
1743 
1744 	mutex_lock(&intf->cmd_rcvrs_mutex);
1745 	for (i = 0; i < IPMI_NUM_CHANNELS; i++) {
1746 		if (((1 << i) & chans) == 0)
1747 			continue;
1748 		rcvr = find_cmd_rcvr(intf, netfn, cmd, i);
1749 		if (rcvr == NULL)
1750 			continue;
1751 		if (rcvr->user == user) {
1752 			rv = 0;
1753 			rcvr->chans &= ~chans;
1754 			if (rcvr->chans == 0) {
1755 				list_del_rcu(&rcvr->link);
1756 				rcvr->next = rcvrs;
1757 				rcvrs = rcvr;
1758 			}
1759 		}
1760 	}
1761 	mutex_unlock(&intf->cmd_rcvrs_mutex);
1762 	synchronize_rcu();
1763 	release_ipmi_user(user, index);
1764 	while (rcvrs) {
1765 		smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_COMMANDS);
1766 		rcvr = rcvrs;
1767 		rcvrs = rcvr->next;
1768 		kfree(rcvr);
1769 	}
1770 
1771 	return rv;
1772 }
1773 EXPORT_SYMBOL(ipmi_unregister_for_cmd);
1774 
1775 unsigned char
ipmb_checksum(unsigned char * data,int size)1776 ipmb_checksum(unsigned char *data, int size)
1777 {
1778 	unsigned char csum = 0;
1779 
1780 	for (; size > 0; size--, data++)
1781 		csum += *data;
1782 
1783 	return -csum;
1784 }
1785 EXPORT_SYMBOL(ipmb_checksum);
1786 
format_ipmb_msg(struct ipmi_smi_msg * smi_msg,struct kernel_ipmi_msg * msg,struct ipmi_ipmb_addr * ipmb_addr,long msgid,unsigned char ipmb_seq,int broadcast,unsigned char source_address,unsigned char source_lun)1787 static inline void format_ipmb_msg(struct ipmi_smi_msg   *smi_msg,
1788 				   struct kernel_ipmi_msg *msg,
1789 				   struct ipmi_ipmb_addr *ipmb_addr,
1790 				   long                  msgid,
1791 				   unsigned char         ipmb_seq,
1792 				   int                   broadcast,
1793 				   unsigned char         source_address,
1794 				   unsigned char         source_lun)
1795 {
1796 	int i = broadcast;
1797 
1798 	/* Format the IPMB header data. */
1799 	smi_msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
1800 	smi_msg->data[1] = IPMI_SEND_MSG_CMD;
1801 	smi_msg->data[2] = ipmb_addr->channel;
1802 	if (broadcast)
1803 		smi_msg->data[3] = 0;
1804 	smi_msg->data[i+3] = ipmb_addr->slave_addr;
1805 	smi_msg->data[i+4] = (msg->netfn << 2) | (ipmb_addr->lun & 0x3);
1806 	smi_msg->data[i+5] = ipmb_checksum(&smi_msg->data[i + 3], 2);
1807 	smi_msg->data[i+6] = source_address;
1808 	smi_msg->data[i+7] = (ipmb_seq << 2) | source_lun;
1809 	smi_msg->data[i+8] = msg->cmd;
1810 
1811 	/* Now tack on the data to the message. */
1812 	if (msg->data_len > 0)
1813 		memcpy(&smi_msg->data[i + 9], msg->data, msg->data_len);
1814 	smi_msg->data_size = msg->data_len + 9;
1815 
1816 	/* Now calculate the checksum and tack it on. */
1817 	smi_msg->data[i+smi_msg->data_size]
1818 		= ipmb_checksum(&smi_msg->data[i + 6], smi_msg->data_size - 6);
1819 
1820 	/*
1821 	 * Add on the checksum size and the offset from the
1822 	 * broadcast.
1823 	 */
1824 	smi_msg->data_size += 1 + i;
1825 
1826 	smi_msg->msgid = msgid;
1827 }
1828 
format_lan_msg(struct ipmi_smi_msg * smi_msg,struct kernel_ipmi_msg * msg,struct ipmi_lan_addr * lan_addr,long msgid,unsigned char ipmb_seq,unsigned char source_lun)1829 static inline void format_lan_msg(struct ipmi_smi_msg   *smi_msg,
1830 				  struct kernel_ipmi_msg *msg,
1831 				  struct ipmi_lan_addr  *lan_addr,
1832 				  long                  msgid,
1833 				  unsigned char         ipmb_seq,
1834 				  unsigned char         source_lun)
1835 {
1836 	/* Format the IPMB header data. */
1837 	smi_msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
1838 	smi_msg->data[1] = IPMI_SEND_MSG_CMD;
1839 	smi_msg->data[2] = lan_addr->channel;
1840 	smi_msg->data[3] = lan_addr->session_handle;
1841 	smi_msg->data[4] = lan_addr->remote_SWID;
1842 	smi_msg->data[5] = (msg->netfn << 2) | (lan_addr->lun & 0x3);
1843 	smi_msg->data[6] = ipmb_checksum(&smi_msg->data[4], 2);
1844 	smi_msg->data[7] = lan_addr->local_SWID;
1845 	smi_msg->data[8] = (ipmb_seq << 2) | source_lun;
1846 	smi_msg->data[9] = msg->cmd;
1847 
1848 	/* Now tack on the data to the message. */
1849 	if (msg->data_len > 0)
1850 		memcpy(&smi_msg->data[10], msg->data, msg->data_len);
1851 	smi_msg->data_size = msg->data_len + 10;
1852 
1853 	/* Now calculate the checksum and tack it on. */
1854 	smi_msg->data[smi_msg->data_size]
1855 		= ipmb_checksum(&smi_msg->data[7], smi_msg->data_size - 7);
1856 
1857 	/*
1858 	 * Add on the checksum size and the offset from the
1859 	 * broadcast.
1860 	 */
1861 	smi_msg->data_size += 1;
1862 
1863 	smi_msg->msgid = msgid;
1864 }
1865 
smi_add_send_msg(struct ipmi_smi * intf,struct ipmi_smi_msg * smi_msg,int priority)1866 static struct ipmi_smi_msg *smi_add_send_msg(struct ipmi_smi *intf,
1867 					     struct ipmi_smi_msg *smi_msg,
1868 					     int priority)
1869 {
1870 	if (intf->curr_msg) {
1871 		if (priority > 0)
1872 			list_add_tail(&smi_msg->link, &intf->hp_xmit_msgs);
1873 		else
1874 			list_add_tail(&smi_msg->link, &intf->xmit_msgs);
1875 		smi_msg = NULL;
1876 	} else {
1877 		intf->curr_msg = smi_msg;
1878 	}
1879 
1880 	return smi_msg;
1881 }
1882 
smi_send(struct ipmi_smi * intf,const struct ipmi_smi_handlers * handlers,struct ipmi_smi_msg * smi_msg,int priority)1883 static void smi_send(struct ipmi_smi *intf,
1884 		     const struct ipmi_smi_handlers *handlers,
1885 		     struct ipmi_smi_msg *smi_msg, int priority)
1886 {
1887 	int run_to_completion = intf->run_to_completion;
1888 	unsigned long flags = 0;
1889 
1890 	if (!run_to_completion)
1891 		spin_lock_irqsave(&intf->xmit_msgs_lock, flags);
1892 	smi_msg = smi_add_send_msg(intf, smi_msg, priority);
1893 
1894 	if (!run_to_completion)
1895 		spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags);
1896 
1897 	if (smi_msg)
1898 		handlers->sender(intf->send_info, smi_msg);
1899 }
1900 
is_maintenance_mode_cmd(struct kernel_ipmi_msg * msg)1901 static bool is_maintenance_mode_cmd(struct kernel_ipmi_msg *msg)
1902 {
1903 	return (((msg->netfn == IPMI_NETFN_APP_REQUEST)
1904 		 && ((msg->cmd == IPMI_COLD_RESET_CMD)
1905 		     || (msg->cmd == IPMI_WARM_RESET_CMD)))
1906 		|| (msg->netfn == IPMI_NETFN_FIRMWARE_REQUEST));
1907 }
1908 
i_ipmi_req_sysintf(struct ipmi_smi * intf,struct ipmi_addr * addr,long msgid,struct kernel_ipmi_msg * msg,struct ipmi_smi_msg * smi_msg,struct ipmi_recv_msg * recv_msg,int retries,unsigned int retry_time_ms)1909 static int i_ipmi_req_sysintf(struct ipmi_smi        *intf,
1910 			      struct ipmi_addr       *addr,
1911 			      long                   msgid,
1912 			      struct kernel_ipmi_msg *msg,
1913 			      struct ipmi_smi_msg    *smi_msg,
1914 			      struct ipmi_recv_msg   *recv_msg,
1915 			      int                    retries,
1916 			      unsigned int           retry_time_ms)
1917 {
1918 	struct ipmi_system_interface_addr *smi_addr;
1919 
1920 	if (msg->netfn & 1)
1921 		/* Responses are not allowed to the SMI. */
1922 		return -EINVAL;
1923 
1924 	smi_addr = (struct ipmi_system_interface_addr *) addr;
1925 	if (smi_addr->lun > 3) {
1926 		ipmi_inc_stat(intf, sent_invalid_commands);
1927 		return -EINVAL;
1928 	}
1929 
1930 	memcpy(&recv_msg->addr, smi_addr, sizeof(*smi_addr));
1931 
1932 	if ((msg->netfn == IPMI_NETFN_APP_REQUEST)
1933 	    && ((msg->cmd == IPMI_SEND_MSG_CMD)
1934 		|| (msg->cmd == IPMI_GET_MSG_CMD)
1935 		|| (msg->cmd == IPMI_READ_EVENT_MSG_BUFFER_CMD))) {
1936 		/*
1937 		 * We don't let the user do these, since we manage
1938 		 * the sequence numbers.
1939 		 */
1940 		ipmi_inc_stat(intf, sent_invalid_commands);
1941 		return -EINVAL;
1942 	}
1943 
1944 	if (is_maintenance_mode_cmd(msg)) {
1945 		unsigned long flags;
1946 
1947 		spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
1948 		intf->auto_maintenance_timeout
1949 			= maintenance_mode_timeout_ms;
1950 		if (!intf->maintenance_mode
1951 		    && !intf->maintenance_mode_enable) {
1952 			intf->maintenance_mode_enable = true;
1953 			maintenance_mode_update(intf);
1954 		}
1955 		spin_unlock_irqrestore(&intf->maintenance_mode_lock,
1956 				       flags);
1957 	}
1958 
1959 	if (msg->data_len + 2 > IPMI_MAX_MSG_LENGTH) {
1960 		ipmi_inc_stat(intf, sent_invalid_commands);
1961 		return -EMSGSIZE;
1962 	}
1963 
1964 	smi_msg->data[0] = (msg->netfn << 2) | (smi_addr->lun & 0x3);
1965 	smi_msg->data[1] = msg->cmd;
1966 	smi_msg->msgid = msgid;
1967 	smi_msg->user_data = recv_msg;
1968 	if (msg->data_len > 0)
1969 		memcpy(&smi_msg->data[2], msg->data, msg->data_len);
1970 	smi_msg->data_size = msg->data_len + 2;
1971 	ipmi_inc_stat(intf, sent_local_commands);
1972 
1973 	return 0;
1974 }
1975 
i_ipmi_req_ipmb(struct ipmi_smi * intf,struct ipmi_addr * addr,long msgid,struct kernel_ipmi_msg * msg,struct ipmi_smi_msg * smi_msg,struct ipmi_recv_msg * recv_msg,unsigned char source_address,unsigned char source_lun,int retries,unsigned int retry_time_ms)1976 static int i_ipmi_req_ipmb(struct ipmi_smi        *intf,
1977 			   struct ipmi_addr       *addr,
1978 			   long                   msgid,
1979 			   struct kernel_ipmi_msg *msg,
1980 			   struct ipmi_smi_msg    *smi_msg,
1981 			   struct ipmi_recv_msg   *recv_msg,
1982 			   unsigned char          source_address,
1983 			   unsigned char          source_lun,
1984 			   int                    retries,
1985 			   unsigned int           retry_time_ms)
1986 {
1987 	struct ipmi_ipmb_addr *ipmb_addr;
1988 	unsigned char ipmb_seq;
1989 	long seqid;
1990 	int broadcast = 0;
1991 	struct ipmi_channel *chans;
1992 	int rv = 0;
1993 
1994 	if (addr->channel >= IPMI_MAX_CHANNELS) {
1995 		ipmi_inc_stat(intf, sent_invalid_commands);
1996 		return -EINVAL;
1997 	}
1998 
1999 	chans = READ_ONCE(intf->channel_list)->c;
2000 
2001 	if (chans[addr->channel].medium != IPMI_CHANNEL_MEDIUM_IPMB) {
2002 		ipmi_inc_stat(intf, sent_invalid_commands);
2003 		return -EINVAL;
2004 	}
2005 
2006 	if (addr->addr_type == IPMI_IPMB_BROADCAST_ADDR_TYPE) {
2007 		/*
2008 		 * Broadcasts add a zero at the beginning of the
2009 		 * message, but otherwise is the same as an IPMB
2010 		 * address.
2011 		 */
2012 		addr->addr_type = IPMI_IPMB_ADDR_TYPE;
2013 		broadcast = 1;
2014 		retries = 0; /* Don't retry broadcasts. */
2015 	}
2016 
2017 	/*
2018 	 * 9 for the header and 1 for the checksum, plus
2019 	 * possibly one for the broadcast.
2020 	 */
2021 	if ((msg->data_len + 10 + broadcast) > IPMI_MAX_MSG_LENGTH) {
2022 		ipmi_inc_stat(intf, sent_invalid_commands);
2023 		return -EMSGSIZE;
2024 	}
2025 
2026 	ipmb_addr = (struct ipmi_ipmb_addr *) addr;
2027 	if (ipmb_addr->lun > 3) {
2028 		ipmi_inc_stat(intf, sent_invalid_commands);
2029 		return -EINVAL;
2030 	}
2031 
2032 	memcpy(&recv_msg->addr, ipmb_addr, sizeof(*ipmb_addr));
2033 
2034 	if (recv_msg->msg.netfn & 0x1) {
2035 		/*
2036 		 * It's a response, so use the user's sequence
2037 		 * from msgid.
2038 		 */
2039 		ipmi_inc_stat(intf, sent_ipmb_responses);
2040 		format_ipmb_msg(smi_msg, msg, ipmb_addr, msgid,
2041 				msgid, broadcast,
2042 				source_address, source_lun);
2043 
2044 		/*
2045 		 * Save the receive message so we can use it
2046 		 * to deliver the response.
2047 		 */
2048 		smi_msg->user_data = recv_msg;
2049 	} else {
2050 		/* It's a command, so get a sequence for it. */
2051 		unsigned long flags;
2052 
2053 		spin_lock_irqsave(&intf->seq_lock, flags);
2054 
2055 		if (is_maintenance_mode_cmd(msg))
2056 			intf->ipmb_maintenance_mode_timeout =
2057 				maintenance_mode_timeout_ms;
2058 
2059 		if (intf->ipmb_maintenance_mode_timeout && retry_time_ms == 0)
2060 			/* Different default in maintenance mode */
2061 			retry_time_ms = default_maintenance_retry_ms;
2062 
2063 		/*
2064 		 * Create a sequence number with a 1 second
2065 		 * timeout and 4 retries.
2066 		 */
2067 		rv = intf_next_seq(intf,
2068 				   recv_msg,
2069 				   retry_time_ms,
2070 				   retries,
2071 				   broadcast,
2072 				   &ipmb_seq,
2073 				   &seqid);
2074 		if (rv)
2075 			/*
2076 			 * We have used up all the sequence numbers,
2077 			 * probably, so abort.
2078 			 */
2079 			goto out_err;
2080 
2081 		ipmi_inc_stat(intf, sent_ipmb_commands);
2082 
2083 		/*
2084 		 * Store the sequence number in the message,
2085 		 * so that when the send message response
2086 		 * comes back we can start the timer.
2087 		 */
2088 		format_ipmb_msg(smi_msg, msg, ipmb_addr,
2089 				STORE_SEQ_IN_MSGID(ipmb_seq, seqid),
2090 				ipmb_seq, broadcast,
2091 				source_address, source_lun);
2092 
2093 		/*
2094 		 * Copy the message into the recv message data, so we
2095 		 * can retransmit it later if necessary.
2096 		 */
2097 		memcpy(recv_msg->msg_data, smi_msg->data,
2098 		       smi_msg->data_size);
2099 		recv_msg->msg.data = recv_msg->msg_data;
2100 		recv_msg->msg.data_len = smi_msg->data_size;
2101 
2102 		/*
2103 		 * We don't unlock until here, because we need
2104 		 * to copy the completed message into the
2105 		 * recv_msg before we release the lock.
2106 		 * Otherwise, race conditions may bite us.  I
2107 		 * know that's pretty paranoid, but I prefer
2108 		 * to be correct.
2109 		 */
2110 out_err:
2111 		spin_unlock_irqrestore(&intf->seq_lock, flags);
2112 	}
2113 
2114 	return rv;
2115 }
2116 
i_ipmi_req_ipmb_direct(struct ipmi_smi * intf,struct ipmi_addr * addr,long msgid,struct kernel_ipmi_msg * msg,struct ipmi_smi_msg * smi_msg,struct ipmi_recv_msg * recv_msg,unsigned char source_lun)2117 static int i_ipmi_req_ipmb_direct(struct ipmi_smi        *intf,
2118 				  struct ipmi_addr       *addr,
2119 				  long			 msgid,
2120 				  struct kernel_ipmi_msg *msg,
2121 				  struct ipmi_smi_msg    *smi_msg,
2122 				  struct ipmi_recv_msg   *recv_msg,
2123 				  unsigned char          source_lun)
2124 {
2125 	struct ipmi_ipmb_direct_addr *daddr;
2126 	bool is_cmd = !(recv_msg->msg.netfn & 0x1);
2127 
2128 	if (!(intf->handlers->flags & IPMI_SMI_CAN_HANDLE_IPMB_DIRECT))
2129 		return -EAFNOSUPPORT;
2130 
2131 	/* Responses must have a completion code. */
2132 	if (!is_cmd && msg->data_len < 1) {
2133 		ipmi_inc_stat(intf, sent_invalid_commands);
2134 		return -EINVAL;
2135 	}
2136 
2137 	if ((msg->data_len + 4) > IPMI_MAX_MSG_LENGTH) {
2138 		ipmi_inc_stat(intf, sent_invalid_commands);
2139 		return -EMSGSIZE;
2140 	}
2141 
2142 	daddr = (struct ipmi_ipmb_direct_addr *) addr;
2143 	if (daddr->rq_lun > 3 || daddr->rs_lun > 3) {
2144 		ipmi_inc_stat(intf, sent_invalid_commands);
2145 		return -EINVAL;
2146 	}
2147 
2148 	smi_msg->type = IPMI_SMI_MSG_TYPE_IPMB_DIRECT;
2149 	smi_msg->msgid = msgid;
2150 
2151 	if (is_cmd) {
2152 		smi_msg->data[0] = msg->netfn << 2 | daddr->rs_lun;
2153 		smi_msg->data[2] = recv_msg->msgid << 2 | daddr->rq_lun;
2154 	} else {
2155 		smi_msg->data[0] = msg->netfn << 2 | daddr->rq_lun;
2156 		smi_msg->data[2] = recv_msg->msgid << 2 | daddr->rs_lun;
2157 	}
2158 	smi_msg->data[1] = daddr->slave_addr;
2159 	smi_msg->data[3] = msg->cmd;
2160 
2161 	memcpy(smi_msg->data + 4, msg->data, msg->data_len);
2162 	smi_msg->data_size = msg->data_len + 4;
2163 
2164 	smi_msg->user_data = recv_msg;
2165 
2166 	return 0;
2167 }
2168 
i_ipmi_req_lan(struct ipmi_smi * intf,struct ipmi_addr * addr,long msgid,struct kernel_ipmi_msg * msg,struct ipmi_smi_msg * smi_msg,struct ipmi_recv_msg * recv_msg,unsigned char source_lun,int retries,unsigned int retry_time_ms)2169 static int i_ipmi_req_lan(struct ipmi_smi        *intf,
2170 			  struct ipmi_addr       *addr,
2171 			  long                   msgid,
2172 			  struct kernel_ipmi_msg *msg,
2173 			  struct ipmi_smi_msg    *smi_msg,
2174 			  struct ipmi_recv_msg   *recv_msg,
2175 			  unsigned char          source_lun,
2176 			  int                    retries,
2177 			  unsigned int           retry_time_ms)
2178 {
2179 	struct ipmi_lan_addr  *lan_addr;
2180 	unsigned char ipmb_seq;
2181 	long seqid;
2182 	struct ipmi_channel *chans;
2183 	int rv = 0;
2184 
2185 	if (addr->channel >= IPMI_MAX_CHANNELS) {
2186 		ipmi_inc_stat(intf, sent_invalid_commands);
2187 		return -EINVAL;
2188 	}
2189 
2190 	chans = READ_ONCE(intf->channel_list)->c;
2191 
2192 	if ((chans[addr->channel].medium
2193 				!= IPMI_CHANNEL_MEDIUM_8023LAN)
2194 			&& (chans[addr->channel].medium
2195 			    != IPMI_CHANNEL_MEDIUM_ASYNC)) {
2196 		ipmi_inc_stat(intf, sent_invalid_commands);
2197 		return -EINVAL;
2198 	}
2199 
2200 	/* 11 for the header and 1 for the checksum. */
2201 	if ((msg->data_len + 12) > IPMI_MAX_MSG_LENGTH) {
2202 		ipmi_inc_stat(intf, sent_invalid_commands);
2203 		return -EMSGSIZE;
2204 	}
2205 
2206 	lan_addr = (struct ipmi_lan_addr *) addr;
2207 	if (lan_addr->lun > 3) {
2208 		ipmi_inc_stat(intf, sent_invalid_commands);
2209 		return -EINVAL;
2210 	}
2211 
2212 	memcpy(&recv_msg->addr, lan_addr, sizeof(*lan_addr));
2213 
2214 	if (recv_msg->msg.netfn & 0x1) {
2215 		/*
2216 		 * It's a response, so use the user's sequence
2217 		 * from msgid.
2218 		 */
2219 		ipmi_inc_stat(intf, sent_lan_responses);
2220 		format_lan_msg(smi_msg, msg, lan_addr, msgid,
2221 			       msgid, source_lun);
2222 
2223 		/*
2224 		 * Save the receive message so we can use it
2225 		 * to deliver the response.
2226 		 */
2227 		smi_msg->user_data = recv_msg;
2228 	} else {
2229 		/* It's a command, so get a sequence for it. */
2230 		unsigned long flags;
2231 
2232 		spin_lock_irqsave(&intf->seq_lock, flags);
2233 
2234 		/*
2235 		 * Create a sequence number with a 1 second
2236 		 * timeout and 4 retries.
2237 		 */
2238 		rv = intf_next_seq(intf,
2239 				   recv_msg,
2240 				   retry_time_ms,
2241 				   retries,
2242 				   0,
2243 				   &ipmb_seq,
2244 				   &seqid);
2245 		if (rv)
2246 			/*
2247 			 * We have used up all the sequence numbers,
2248 			 * probably, so abort.
2249 			 */
2250 			goto out_err;
2251 
2252 		ipmi_inc_stat(intf, sent_lan_commands);
2253 
2254 		/*
2255 		 * Store the sequence number in the message,
2256 		 * so that when the send message response
2257 		 * comes back we can start the timer.
2258 		 */
2259 		format_lan_msg(smi_msg, msg, lan_addr,
2260 			       STORE_SEQ_IN_MSGID(ipmb_seq, seqid),
2261 			       ipmb_seq, source_lun);
2262 
2263 		/*
2264 		 * Copy the message into the recv message data, so we
2265 		 * can retransmit it later if necessary.
2266 		 */
2267 		memcpy(recv_msg->msg_data, smi_msg->data,
2268 		       smi_msg->data_size);
2269 		recv_msg->msg.data = recv_msg->msg_data;
2270 		recv_msg->msg.data_len = smi_msg->data_size;
2271 
2272 		/*
2273 		 * We don't unlock until here, because we need
2274 		 * to copy the completed message into the
2275 		 * recv_msg before we release the lock.
2276 		 * Otherwise, race conditions may bite us.  I
2277 		 * know that's pretty paranoid, but I prefer
2278 		 * to be correct.
2279 		 */
2280 out_err:
2281 		spin_unlock_irqrestore(&intf->seq_lock, flags);
2282 	}
2283 
2284 	return rv;
2285 }
2286 
2287 /*
2288  * Separate from ipmi_request so that the user does not have to be
2289  * supplied in certain circumstances (mainly at panic time).  If
2290  * messages are supplied, they will be freed, even if an error
2291  * occurs.
2292  */
i_ipmi_request(struct ipmi_user * user,struct ipmi_smi * intf,struct ipmi_addr * addr,long msgid,struct kernel_ipmi_msg * msg,void * user_msg_data,void * supplied_smi,struct ipmi_recv_msg * supplied_recv,int priority,unsigned char source_address,unsigned char source_lun,int retries,unsigned int retry_time_ms)2293 static int i_ipmi_request(struct ipmi_user     *user,
2294 			  struct ipmi_smi      *intf,
2295 			  struct ipmi_addr     *addr,
2296 			  long                 msgid,
2297 			  struct kernel_ipmi_msg *msg,
2298 			  void                 *user_msg_data,
2299 			  void                 *supplied_smi,
2300 			  struct ipmi_recv_msg *supplied_recv,
2301 			  int                  priority,
2302 			  unsigned char        source_address,
2303 			  unsigned char        source_lun,
2304 			  int                  retries,
2305 			  unsigned int         retry_time_ms)
2306 {
2307 	struct ipmi_smi_msg *smi_msg;
2308 	struct ipmi_recv_msg *recv_msg;
2309 	int rv = 0;
2310 
2311 	if (user) {
2312 		if (atomic_add_return(1, &user->nr_msgs) > max_msgs_per_user) {
2313 			/* Decrement will happen at the end of the routine. */
2314 			rv = -EBUSY;
2315 			goto out;
2316 		}
2317 	}
2318 
2319 	if (supplied_recv)
2320 		recv_msg = supplied_recv;
2321 	else {
2322 		recv_msg = ipmi_alloc_recv_msg();
2323 		if (recv_msg == NULL) {
2324 			rv = -ENOMEM;
2325 			goto out;
2326 		}
2327 	}
2328 	recv_msg->user_msg_data = user_msg_data;
2329 
2330 	if (supplied_smi)
2331 		smi_msg = supplied_smi;
2332 	else {
2333 		smi_msg = ipmi_alloc_smi_msg();
2334 		if (smi_msg == NULL) {
2335 			if (!supplied_recv)
2336 				ipmi_free_recv_msg(recv_msg);
2337 			rv = -ENOMEM;
2338 			goto out;
2339 		}
2340 	}
2341 
2342 	rcu_read_lock();
2343 	if (intf->in_shutdown) {
2344 		rv = -ENODEV;
2345 		goto out_err;
2346 	}
2347 
2348 	recv_msg->user = user;
2349 	if (user)
2350 		/* The put happens when the message is freed. */
2351 		kref_get(&user->refcount);
2352 	recv_msg->msgid = msgid;
2353 	/*
2354 	 * Store the message to send in the receive message so timeout
2355 	 * responses can get the proper response data.
2356 	 */
2357 	recv_msg->msg = *msg;
2358 
2359 	if (addr->addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE) {
2360 		rv = i_ipmi_req_sysintf(intf, addr, msgid, msg, smi_msg,
2361 					recv_msg, retries, retry_time_ms);
2362 	} else if (is_ipmb_addr(addr) || is_ipmb_bcast_addr(addr)) {
2363 		rv = i_ipmi_req_ipmb(intf, addr, msgid, msg, smi_msg, recv_msg,
2364 				     source_address, source_lun,
2365 				     retries, retry_time_ms);
2366 	} else if (is_ipmb_direct_addr(addr)) {
2367 		rv = i_ipmi_req_ipmb_direct(intf, addr, msgid, msg, smi_msg,
2368 					    recv_msg, source_lun);
2369 	} else if (is_lan_addr(addr)) {
2370 		rv = i_ipmi_req_lan(intf, addr, msgid, msg, smi_msg, recv_msg,
2371 				    source_lun, retries, retry_time_ms);
2372 	} else {
2373 	    /* Unknown address type. */
2374 		ipmi_inc_stat(intf, sent_invalid_commands);
2375 		rv = -EINVAL;
2376 	}
2377 
2378 	if (rv) {
2379 out_err:
2380 		ipmi_free_smi_msg(smi_msg);
2381 		ipmi_free_recv_msg(recv_msg);
2382 	} else {
2383 		dev_dbg(intf->si_dev, "Send: %*ph\n",
2384 			smi_msg->data_size, smi_msg->data);
2385 
2386 		smi_send(intf, intf->handlers, smi_msg, priority);
2387 	}
2388 	rcu_read_unlock();
2389 
2390 out:
2391 	if (rv && user)
2392 		atomic_dec(&user->nr_msgs);
2393 	return rv;
2394 }
2395 
check_addr(struct ipmi_smi * intf,struct ipmi_addr * addr,unsigned char * saddr,unsigned char * lun)2396 static int check_addr(struct ipmi_smi  *intf,
2397 		      struct ipmi_addr *addr,
2398 		      unsigned char    *saddr,
2399 		      unsigned char    *lun)
2400 {
2401 	if (addr->channel >= IPMI_MAX_CHANNELS)
2402 		return -EINVAL;
2403 	addr->channel = array_index_nospec(addr->channel, IPMI_MAX_CHANNELS);
2404 	*lun = intf->addrinfo[addr->channel].lun;
2405 	*saddr = intf->addrinfo[addr->channel].address;
2406 	return 0;
2407 }
2408 
ipmi_request_settime(struct ipmi_user * user,struct ipmi_addr * addr,long msgid,struct kernel_ipmi_msg * msg,void * user_msg_data,int priority,int retries,unsigned int retry_time_ms)2409 int ipmi_request_settime(struct ipmi_user *user,
2410 			 struct ipmi_addr *addr,
2411 			 long             msgid,
2412 			 struct kernel_ipmi_msg  *msg,
2413 			 void             *user_msg_data,
2414 			 int              priority,
2415 			 int              retries,
2416 			 unsigned int     retry_time_ms)
2417 {
2418 	unsigned char saddr = 0, lun = 0;
2419 	int rv, index;
2420 
2421 	if (!user)
2422 		return -EINVAL;
2423 
2424 	user = acquire_ipmi_user(user, &index);
2425 	if (!user)
2426 		return -ENODEV;
2427 
2428 	rv = check_addr(user->intf, addr, &saddr, &lun);
2429 	if (!rv)
2430 		rv = i_ipmi_request(user,
2431 				    user->intf,
2432 				    addr,
2433 				    msgid,
2434 				    msg,
2435 				    user_msg_data,
2436 				    NULL, NULL,
2437 				    priority,
2438 				    saddr,
2439 				    lun,
2440 				    retries,
2441 				    retry_time_ms);
2442 
2443 	release_ipmi_user(user, index);
2444 	return rv;
2445 }
2446 EXPORT_SYMBOL(ipmi_request_settime);
2447 
ipmi_request_supply_msgs(struct ipmi_user * user,struct ipmi_addr * addr,long msgid,struct kernel_ipmi_msg * msg,void * user_msg_data,void * supplied_smi,struct ipmi_recv_msg * supplied_recv,int priority)2448 int ipmi_request_supply_msgs(struct ipmi_user     *user,
2449 			     struct ipmi_addr     *addr,
2450 			     long                 msgid,
2451 			     struct kernel_ipmi_msg *msg,
2452 			     void                 *user_msg_data,
2453 			     void                 *supplied_smi,
2454 			     struct ipmi_recv_msg *supplied_recv,
2455 			     int                  priority)
2456 {
2457 	unsigned char saddr = 0, lun = 0;
2458 	int rv, index;
2459 
2460 	if (!user)
2461 		return -EINVAL;
2462 
2463 	user = acquire_ipmi_user(user, &index);
2464 	if (!user)
2465 		return -ENODEV;
2466 
2467 	rv = check_addr(user->intf, addr, &saddr, &lun);
2468 	if (!rv)
2469 		rv = i_ipmi_request(user,
2470 				    user->intf,
2471 				    addr,
2472 				    msgid,
2473 				    msg,
2474 				    user_msg_data,
2475 				    supplied_smi,
2476 				    supplied_recv,
2477 				    priority,
2478 				    saddr,
2479 				    lun,
2480 				    -1, 0);
2481 
2482 	release_ipmi_user(user, index);
2483 	return rv;
2484 }
2485 EXPORT_SYMBOL(ipmi_request_supply_msgs);
2486 
bmc_device_id_handler(struct ipmi_smi * intf,struct ipmi_recv_msg * msg)2487 static void bmc_device_id_handler(struct ipmi_smi *intf,
2488 				  struct ipmi_recv_msg *msg)
2489 {
2490 	int rv;
2491 
2492 	if ((msg->addr.addr_type != IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
2493 			|| (msg->msg.netfn != IPMI_NETFN_APP_RESPONSE)
2494 			|| (msg->msg.cmd != IPMI_GET_DEVICE_ID_CMD)) {
2495 		dev_warn(intf->si_dev,
2496 			 "invalid device_id msg: addr_type=%d netfn=%x cmd=%x\n",
2497 			 msg->addr.addr_type, msg->msg.netfn, msg->msg.cmd);
2498 		return;
2499 	}
2500 
2501 	if (msg->msg.data[0]) {
2502 		dev_warn(intf->si_dev, "device id fetch failed: 0x%2.2x\n",
2503 			 msg->msg.data[0]);
2504 		intf->bmc->dyn_id_set = 0;
2505 		goto out;
2506 	}
2507 
2508 	rv = ipmi_demangle_device_id(msg->msg.netfn, msg->msg.cmd,
2509 			msg->msg.data, msg->msg.data_len, &intf->bmc->fetch_id);
2510 	if (rv) {
2511 		dev_warn(intf->si_dev, "device id demangle failed: %d\n", rv);
2512 		/* record completion code when error */
2513 		intf->bmc->cc = msg->msg.data[0];
2514 		intf->bmc->dyn_id_set = 0;
2515 	} else {
2516 		/*
2517 		 * Make sure the id data is available before setting
2518 		 * dyn_id_set.
2519 		 */
2520 		smp_wmb();
2521 		intf->bmc->dyn_id_set = 1;
2522 	}
2523 out:
2524 	wake_up(&intf->waitq);
2525 }
2526 
2527 static int
send_get_device_id_cmd(struct ipmi_smi * intf)2528 send_get_device_id_cmd(struct ipmi_smi *intf)
2529 {
2530 	struct ipmi_system_interface_addr si;
2531 	struct kernel_ipmi_msg msg;
2532 
2533 	si.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
2534 	si.channel = IPMI_BMC_CHANNEL;
2535 	si.lun = 0;
2536 
2537 	msg.netfn = IPMI_NETFN_APP_REQUEST;
2538 	msg.cmd = IPMI_GET_DEVICE_ID_CMD;
2539 	msg.data = NULL;
2540 	msg.data_len = 0;
2541 
2542 	return i_ipmi_request(NULL,
2543 			      intf,
2544 			      (struct ipmi_addr *) &si,
2545 			      0,
2546 			      &msg,
2547 			      intf,
2548 			      NULL,
2549 			      NULL,
2550 			      0,
2551 			      intf->addrinfo[0].address,
2552 			      intf->addrinfo[0].lun,
2553 			      -1, 0);
2554 }
2555 
__get_device_id(struct ipmi_smi * intf,struct bmc_device * bmc)2556 static int __get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc)
2557 {
2558 	int rv;
2559 	unsigned int retry_count = 0;
2560 
2561 	intf->null_user_handler = bmc_device_id_handler;
2562 
2563 retry:
2564 	bmc->cc = 0;
2565 	bmc->dyn_id_set = 2;
2566 
2567 	rv = send_get_device_id_cmd(intf);
2568 	if (rv)
2569 		goto out_reset_handler;
2570 
2571 	wait_event(intf->waitq, bmc->dyn_id_set != 2);
2572 
2573 	if (!bmc->dyn_id_set) {
2574 		if (bmc->cc != IPMI_CC_NO_ERROR &&
2575 		    ++retry_count <= GET_DEVICE_ID_MAX_RETRY) {
2576 			msleep(500);
2577 			dev_warn(intf->si_dev,
2578 			    "BMC returned 0x%2.2x, retry get bmc device id\n",
2579 			    bmc->cc);
2580 			goto retry;
2581 		}
2582 
2583 		rv = -EIO; /* Something went wrong in the fetch. */
2584 	}
2585 
2586 	/* dyn_id_set makes the id data available. */
2587 	smp_rmb();
2588 
2589 out_reset_handler:
2590 	intf->null_user_handler = NULL;
2591 
2592 	return rv;
2593 }
2594 
2595 /*
2596  * Fetch the device id for the bmc/interface.  You must pass in either
2597  * bmc or intf, this code will get the other one.  If the data has
2598  * been recently fetched, this will just use the cached data.  Otherwise
2599  * it will run a new fetch.
2600  *
2601  * Except for the first time this is called (in ipmi_add_smi()),
2602  * this will always return good data;
2603  */
__bmc_get_device_id(struct ipmi_smi * intf,struct bmc_device * bmc,struct ipmi_device_id * id,bool * guid_set,guid_t * guid,int intf_num)2604 static int __bmc_get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc,
2605 			       struct ipmi_device_id *id,
2606 			       bool *guid_set, guid_t *guid, int intf_num)
2607 {
2608 	int rv = 0;
2609 	int prev_dyn_id_set, prev_guid_set;
2610 	bool intf_set = intf != NULL;
2611 
2612 	if (!intf) {
2613 		mutex_lock(&bmc->dyn_mutex);
2614 retry_bmc_lock:
2615 		if (list_empty(&bmc->intfs)) {
2616 			mutex_unlock(&bmc->dyn_mutex);
2617 			return -ENOENT;
2618 		}
2619 		intf = list_first_entry(&bmc->intfs, struct ipmi_smi,
2620 					bmc_link);
2621 		kref_get(&intf->refcount);
2622 		mutex_unlock(&bmc->dyn_mutex);
2623 		mutex_lock(&intf->bmc_reg_mutex);
2624 		mutex_lock(&bmc->dyn_mutex);
2625 		if (intf != list_first_entry(&bmc->intfs, struct ipmi_smi,
2626 					     bmc_link)) {
2627 			mutex_unlock(&intf->bmc_reg_mutex);
2628 			kref_put(&intf->refcount, intf_free);
2629 			goto retry_bmc_lock;
2630 		}
2631 	} else {
2632 		mutex_lock(&intf->bmc_reg_mutex);
2633 		bmc = intf->bmc;
2634 		mutex_lock(&bmc->dyn_mutex);
2635 		kref_get(&intf->refcount);
2636 	}
2637 
2638 	/* If we have a valid and current ID, just return that. */
2639 	if (intf->in_bmc_register ||
2640 	    (bmc->dyn_id_set && time_is_after_jiffies(bmc->dyn_id_expiry)))
2641 		goto out_noprocessing;
2642 
2643 	prev_guid_set = bmc->dyn_guid_set;
2644 	__get_guid(intf);
2645 
2646 	prev_dyn_id_set = bmc->dyn_id_set;
2647 	rv = __get_device_id(intf, bmc);
2648 	if (rv)
2649 		goto out;
2650 
2651 	/*
2652 	 * The guid, device id, manufacturer id, and product id should
2653 	 * not change on a BMC.  If it does we have to do some dancing.
2654 	 */
2655 	if (!intf->bmc_registered
2656 	    || (!prev_guid_set && bmc->dyn_guid_set)
2657 	    || (!prev_dyn_id_set && bmc->dyn_id_set)
2658 	    || (prev_guid_set && bmc->dyn_guid_set
2659 		&& !guid_equal(&bmc->guid, &bmc->fetch_guid))
2660 	    || bmc->id.device_id != bmc->fetch_id.device_id
2661 	    || bmc->id.manufacturer_id != bmc->fetch_id.manufacturer_id
2662 	    || bmc->id.product_id != bmc->fetch_id.product_id) {
2663 		struct ipmi_device_id id = bmc->fetch_id;
2664 		int guid_set = bmc->dyn_guid_set;
2665 		guid_t guid;
2666 
2667 		guid = bmc->fetch_guid;
2668 		mutex_unlock(&bmc->dyn_mutex);
2669 
2670 		__ipmi_bmc_unregister(intf);
2671 		/* Fill in the temporary BMC for good measure. */
2672 		intf->bmc->id = id;
2673 		intf->bmc->dyn_guid_set = guid_set;
2674 		intf->bmc->guid = guid;
2675 		if (__ipmi_bmc_register(intf, &id, guid_set, &guid, intf_num))
2676 			need_waiter(intf); /* Retry later on an error. */
2677 		else
2678 			__scan_channels(intf, &id);
2679 
2680 
2681 		if (!intf_set) {
2682 			/*
2683 			 * We weren't given the interface on the
2684 			 * command line, so restart the operation on
2685 			 * the next interface for the BMC.
2686 			 */
2687 			mutex_unlock(&intf->bmc_reg_mutex);
2688 			mutex_lock(&bmc->dyn_mutex);
2689 			goto retry_bmc_lock;
2690 		}
2691 
2692 		/* We have a new BMC, set it up. */
2693 		bmc = intf->bmc;
2694 		mutex_lock(&bmc->dyn_mutex);
2695 		goto out_noprocessing;
2696 	} else if (memcmp(&bmc->fetch_id, &bmc->id, sizeof(bmc->id)))
2697 		/* Version info changes, scan the channels again. */
2698 		__scan_channels(intf, &bmc->fetch_id);
2699 
2700 	bmc->dyn_id_expiry = jiffies + IPMI_DYN_DEV_ID_EXPIRY;
2701 
2702 out:
2703 	if (rv && prev_dyn_id_set) {
2704 		rv = 0; /* Ignore failures if we have previous data. */
2705 		bmc->dyn_id_set = prev_dyn_id_set;
2706 	}
2707 	if (!rv) {
2708 		bmc->id = bmc->fetch_id;
2709 		if (bmc->dyn_guid_set)
2710 			bmc->guid = bmc->fetch_guid;
2711 		else if (prev_guid_set)
2712 			/*
2713 			 * The guid used to be valid and it failed to fetch,
2714 			 * just use the cached value.
2715 			 */
2716 			bmc->dyn_guid_set = prev_guid_set;
2717 	}
2718 out_noprocessing:
2719 	if (!rv) {
2720 		if (id)
2721 			*id = bmc->id;
2722 
2723 		if (guid_set)
2724 			*guid_set = bmc->dyn_guid_set;
2725 
2726 		if (guid && bmc->dyn_guid_set)
2727 			*guid =  bmc->guid;
2728 	}
2729 
2730 	mutex_unlock(&bmc->dyn_mutex);
2731 	mutex_unlock(&intf->bmc_reg_mutex);
2732 
2733 	kref_put(&intf->refcount, intf_free);
2734 	return rv;
2735 }
2736 
bmc_get_device_id(struct ipmi_smi * intf,struct bmc_device * bmc,struct ipmi_device_id * id,bool * guid_set,guid_t * guid)2737 static int bmc_get_device_id(struct ipmi_smi *intf, struct bmc_device *bmc,
2738 			     struct ipmi_device_id *id,
2739 			     bool *guid_set, guid_t *guid)
2740 {
2741 	return __bmc_get_device_id(intf, bmc, id, guid_set, guid, -1);
2742 }
2743 
device_id_show(struct device * dev,struct device_attribute * attr,char * buf)2744 static ssize_t device_id_show(struct device *dev,
2745 			      struct device_attribute *attr,
2746 			      char *buf)
2747 {
2748 	struct bmc_device *bmc = to_bmc_device(dev);
2749 	struct ipmi_device_id id;
2750 	int rv;
2751 
2752 	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2753 	if (rv)
2754 		return rv;
2755 
2756 	return sysfs_emit(buf, "%u\n", id.device_id);
2757 }
2758 static DEVICE_ATTR_RO(device_id);
2759 
provides_device_sdrs_show(struct device * dev,struct device_attribute * attr,char * buf)2760 static ssize_t provides_device_sdrs_show(struct device *dev,
2761 					 struct device_attribute *attr,
2762 					 char *buf)
2763 {
2764 	struct bmc_device *bmc = to_bmc_device(dev);
2765 	struct ipmi_device_id id;
2766 	int rv;
2767 
2768 	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2769 	if (rv)
2770 		return rv;
2771 
2772 	return sysfs_emit(buf, "%u\n", (id.device_revision & 0x80) >> 7);
2773 }
2774 static DEVICE_ATTR_RO(provides_device_sdrs);
2775 
revision_show(struct device * dev,struct device_attribute * attr,char * buf)2776 static ssize_t revision_show(struct device *dev, struct device_attribute *attr,
2777 			     char *buf)
2778 {
2779 	struct bmc_device *bmc = to_bmc_device(dev);
2780 	struct ipmi_device_id id;
2781 	int rv;
2782 
2783 	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2784 	if (rv)
2785 		return rv;
2786 
2787 	return sysfs_emit(buf, "%u\n", id.device_revision & 0x0F);
2788 }
2789 static DEVICE_ATTR_RO(revision);
2790 
firmware_revision_show(struct device * dev,struct device_attribute * attr,char * buf)2791 static ssize_t firmware_revision_show(struct device *dev,
2792 				      struct device_attribute *attr,
2793 				      char *buf)
2794 {
2795 	struct bmc_device *bmc = to_bmc_device(dev);
2796 	struct ipmi_device_id id;
2797 	int rv;
2798 
2799 	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2800 	if (rv)
2801 		return rv;
2802 
2803 	return sysfs_emit(buf, "%u.%x\n", id.firmware_revision_1,
2804 			id.firmware_revision_2);
2805 }
2806 static DEVICE_ATTR_RO(firmware_revision);
2807 
ipmi_version_show(struct device * dev,struct device_attribute * attr,char * buf)2808 static ssize_t ipmi_version_show(struct device *dev,
2809 				 struct device_attribute *attr,
2810 				 char *buf)
2811 {
2812 	struct bmc_device *bmc = to_bmc_device(dev);
2813 	struct ipmi_device_id id;
2814 	int rv;
2815 
2816 	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2817 	if (rv)
2818 		return rv;
2819 
2820 	return sysfs_emit(buf, "%u.%u\n",
2821 			ipmi_version_major(&id),
2822 			ipmi_version_minor(&id));
2823 }
2824 static DEVICE_ATTR_RO(ipmi_version);
2825 
add_dev_support_show(struct device * dev,struct device_attribute * attr,char * buf)2826 static ssize_t add_dev_support_show(struct device *dev,
2827 				    struct device_attribute *attr,
2828 				    char *buf)
2829 {
2830 	struct bmc_device *bmc = to_bmc_device(dev);
2831 	struct ipmi_device_id id;
2832 	int rv;
2833 
2834 	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2835 	if (rv)
2836 		return rv;
2837 
2838 	return sysfs_emit(buf, "0x%02x\n", id.additional_device_support);
2839 }
2840 static DEVICE_ATTR(additional_device_support, S_IRUGO, add_dev_support_show,
2841 		   NULL);
2842 
manufacturer_id_show(struct device * dev,struct device_attribute * attr,char * buf)2843 static ssize_t manufacturer_id_show(struct device *dev,
2844 				    struct device_attribute *attr,
2845 				    char *buf)
2846 {
2847 	struct bmc_device *bmc = to_bmc_device(dev);
2848 	struct ipmi_device_id id;
2849 	int rv;
2850 
2851 	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2852 	if (rv)
2853 		return rv;
2854 
2855 	return sysfs_emit(buf, "0x%6.6x\n", id.manufacturer_id);
2856 }
2857 static DEVICE_ATTR_RO(manufacturer_id);
2858 
product_id_show(struct device * dev,struct device_attribute * attr,char * buf)2859 static ssize_t product_id_show(struct device *dev,
2860 			       struct device_attribute *attr,
2861 			       char *buf)
2862 {
2863 	struct bmc_device *bmc = to_bmc_device(dev);
2864 	struct ipmi_device_id id;
2865 	int rv;
2866 
2867 	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2868 	if (rv)
2869 		return rv;
2870 
2871 	return sysfs_emit(buf, "0x%4.4x\n", id.product_id);
2872 }
2873 static DEVICE_ATTR_RO(product_id);
2874 
aux_firmware_rev_show(struct device * dev,struct device_attribute * attr,char * buf)2875 static ssize_t aux_firmware_rev_show(struct device *dev,
2876 				     struct device_attribute *attr,
2877 				     char *buf)
2878 {
2879 	struct bmc_device *bmc = to_bmc_device(dev);
2880 	struct ipmi_device_id id;
2881 	int rv;
2882 
2883 	rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2884 	if (rv)
2885 		return rv;
2886 
2887 	return sysfs_emit(buf, "0x%02x 0x%02x 0x%02x 0x%02x\n",
2888 			id.aux_firmware_revision[3],
2889 			id.aux_firmware_revision[2],
2890 			id.aux_firmware_revision[1],
2891 			id.aux_firmware_revision[0]);
2892 }
2893 static DEVICE_ATTR(aux_firmware_revision, S_IRUGO, aux_firmware_rev_show, NULL);
2894 
guid_show(struct device * dev,struct device_attribute * attr,char * buf)2895 static ssize_t guid_show(struct device *dev, struct device_attribute *attr,
2896 			 char *buf)
2897 {
2898 	struct bmc_device *bmc = to_bmc_device(dev);
2899 	bool guid_set;
2900 	guid_t guid;
2901 	int rv;
2902 
2903 	rv = bmc_get_device_id(NULL, bmc, NULL, &guid_set, &guid);
2904 	if (rv)
2905 		return rv;
2906 	if (!guid_set)
2907 		return -ENOENT;
2908 
2909 	return sysfs_emit(buf, "%pUl\n", &guid);
2910 }
2911 static DEVICE_ATTR_RO(guid);
2912 
2913 static struct attribute *bmc_dev_attrs[] = {
2914 	&dev_attr_device_id.attr,
2915 	&dev_attr_provides_device_sdrs.attr,
2916 	&dev_attr_revision.attr,
2917 	&dev_attr_firmware_revision.attr,
2918 	&dev_attr_ipmi_version.attr,
2919 	&dev_attr_additional_device_support.attr,
2920 	&dev_attr_manufacturer_id.attr,
2921 	&dev_attr_product_id.attr,
2922 	&dev_attr_aux_firmware_revision.attr,
2923 	&dev_attr_guid.attr,
2924 	NULL
2925 };
2926 
bmc_dev_attr_is_visible(struct kobject * kobj,struct attribute * attr,int idx)2927 static umode_t bmc_dev_attr_is_visible(struct kobject *kobj,
2928 				       struct attribute *attr, int idx)
2929 {
2930 	struct device *dev = kobj_to_dev(kobj);
2931 	struct bmc_device *bmc = to_bmc_device(dev);
2932 	umode_t mode = attr->mode;
2933 	int rv;
2934 
2935 	if (attr == &dev_attr_aux_firmware_revision.attr) {
2936 		struct ipmi_device_id id;
2937 
2938 		rv = bmc_get_device_id(NULL, bmc, &id, NULL, NULL);
2939 		return (!rv && id.aux_firmware_revision_set) ? mode : 0;
2940 	}
2941 	if (attr == &dev_attr_guid.attr) {
2942 		bool guid_set;
2943 
2944 		rv = bmc_get_device_id(NULL, bmc, NULL, &guid_set, NULL);
2945 		return (!rv && guid_set) ? mode : 0;
2946 	}
2947 	return mode;
2948 }
2949 
2950 static const struct attribute_group bmc_dev_attr_group = {
2951 	.attrs		= bmc_dev_attrs,
2952 	.is_visible	= bmc_dev_attr_is_visible,
2953 };
2954 
2955 static const struct attribute_group *bmc_dev_attr_groups[] = {
2956 	&bmc_dev_attr_group,
2957 	NULL
2958 };
2959 
2960 static const struct device_type bmc_device_type = {
2961 	.groups		= bmc_dev_attr_groups,
2962 };
2963 
__find_bmc_guid(struct device * dev,const void * data)2964 static int __find_bmc_guid(struct device *dev, const void *data)
2965 {
2966 	const guid_t *guid = data;
2967 	struct bmc_device *bmc;
2968 	int rv;
2969 
2970 	if (dev->type != &bmc_device_type)
2971 		return 0;
2972 
2973 	bmc = to_bmc_device(dev);
2974 	rv = bmc->dyn_guid_set && guid_equal(&bmc->guid, guid);
2975 	if (rv)
2976 		rv = kref_get_unless_zero(&bmc->usecount);
2977 	return rv;
2978 }
2979 
2980 /*
2981  * Returns with the bmc's usecount incremented, if it is non-NULL.
2982  */
ipmi_find_bmc_guid(struct device_driver * drv,guid_t * guid)2983 static struct bmc_device *ipmi_find_bmc_guid(struct device_driver *drv,
2984 					     guid_t *guid)
2985 {
2986 	struct device *dev;
2987 	struct bmc_device *bmc = NULL;
2988 
2989 	dev = driver_find_device(drv, NULL, guid, __find_bmc_guid);
2990 	if (dev) {
2991 		bmc = to_bmc_device(dev);
2992 		put_device(dev);
2993 	}
2994 	return bmc;
2995 }
2996 
2997 struct prod_dev_id {
2998 	unsigned int  product_id;
2999 	unsigned char device_id;
3000 };
3001 
__find_bmc_prod_dev_id(struct device * dev,const void * data)3002 static int __find_bmc_prod_dev_id(struct device *dev, const void *data)
3003 {
3004 	const struct prod_dev_id *cid = data;
3005 	struct bmc_device *bmc;
3006 	int rv;
3007 
3008 	if (dev->type != &bmc_device_type)
3009 		return 0;
3010 
3011 	bmc = to_bmc_device(dev);
3012 	rv = (bmc->id.product_id == cid->product_id
3013 	      && bmc->id.device_id == cid->device_id);
3014 	if (rv)
3015 		rv = kref_get_unless_zero(&bmc->usecount);
3016 	return rv;
3017 }
3018 
3019 /*
3020  * Returns with the bmc's usecount incremented, if it is non-NULL.
3021  */
ipmi_find_bmc_prod_dev_id(struct device_driver * drv,unsigned int product_id,unsigned char device_id)3022 static struct bmc_device *ipmi_find_bmc_prod_dev_id(
3023 	struct device_driver *drv,
3024 	unsigned int product_id, unsigned char device_id)
3025 {
3026 	struct prod_dev_id id = {
3027 		.product_id = product_id,
3028 		.device_id = device_id,
3029 	};
3030 	struct device *dev;
3031 	struct bmc_device *bmc = NULL;
3032 
3033 	dev = driver_find_device(drv, NULL, &id, __find_bmc_prod_dev_id);
3034 	if (dev) {
3035 		bmc = to_bmc_device(dev);
3036 		put_device(dev);
3037 	}
3038 	return bmc;
3039 }
3040 
3041 static DEFINE_IDA(ipmi_bmc_ida);
3042 
3043 static void
release_bmc_device(struct device * dev)3044 release_bmc_device(struct device *dev)
3045 {
3046 	kfree(to_bmc_device(dev));
3047 }
3048 
cleanup_bmc_work(struct work_struct * work)3049 static void cleanup_bmc_work(struct work_struct *work)
3050 {
3051 	struct bmc_device *bmc = container_of(work, struct bmc_device,
3052 					      remove_work);
3053 	int id = bmc->pdev.id; /* Unregister overwrites id */
3054 
3055 	platform_device_unregister(&bmc->pdev);
3056 	ida_simple_remove(&ipmi_bmc_ida, id);
3057 }
3058 
3059 static void
cleanup_bmc_device(struct kref * ref)3060 cleanup_bmc_device(struct kref *ref)
3061 {
3062 	struct bmc_device *bmc = container_of(ref, struct bmc_device, usecount);
3063 
3064 	/*
3065 	 * Remove the platform device in a work queue to avoid issues
3066 	 * with removing the device attributes while reading a device
3067 	 * attribute.
3068 	 */
3069 	queue_work(remove_work_wq, &bmc->remove_work);
3070 }
3071 
3072 /*
3073  * Must be called with intf->bmc_reg_mutex held.
3074  */
__ipmi_bmc_unregister(struct ipmi_smi * intf)3075 static void __ipmi_bmc_unregister(struct ipmi_smi *intf)
3076 {
3077 	struct bmc_device *bmc = intf->bmc;
3078 
3079 	if (!intf->bmc_registered)
3080 		return;
3081 
3082 	sysfs_remove_link(&intf->si_dev->kobj, "bmc");
3083 	sysfs_remove_link(&bmc->pdev.dev.kobj, intf->my_dev_name);
3084 	kfree(intf->my_dev_name);
3085 	intf->my_dev_name = NULL;
3086 
3087 	mutex_lock(&bmc->dyn_mutex);
3088 	list_del(&intf->bmc_link);
3089 	mutex_unlock(&bmc->dyn_mutex);
3090 	intf->bmc = &intf->tmp_bmc;
3091 	kref_put(&bmc->usecount, cleanup_bmc_device);
3092 	intf->bmc_registered = false;
3093 }
3094 
ipmi_bmc_unregister(struct ipmi_smi * intf)3095 static void ipmi_bmc_unregister(struct ipmi_smi *intf)
3096 {
3097 	mutex_lock(&intf->bmc_reg_mutex);
3098 	__ipmi_bmc_unregister(intf);
3099 	mutex_unlock(&intf->bmc_reg_mutex);
3100 }
3101 
3102 /*
3103  * Must be called with intf->bmc_reg_mutex held.
3104  */
__ipmi_bmc_register(struct ipmi_smi * intf,struct ipmi_device_id * id,bool guid_set,guid_t * guid,int intf_num)3105 static int __ipmi_bmc_register(struct ipmi_smi *intf,
3106 			       struct ipmi_device_id *id,
3107 			       bool guid_set, guid_t *guid, int intf_num)
3108 {
3109 	int               rv;
3110 	struct bmc_device *bmc;
3111 	struct bmc_device *old_bmc;
3112 
3113 	/*
3114 	 * platform_device_register() can cause bmc_reg_mutex to
3115 	 * be claimed because of the is_visible functions of
3116 	 * the attributes.  Eliminate possible recursion and
3117 	 * release the lock.
3118 	 */
3119 	intf->in_bmc_register = true;
3120 	mutex_unlock(&intf->bmc_reg_mutex);
3121 
3122 	/*
3123 	 * Try to find if there is an bmc_device struct
3124 	 * representing the interfaced BMC already
3125 	 */
3126 	mutex_lock(&ipmidriver_mutex);
3127 	if (guid_set)
3128 		old_bmc = ipmi_find_bmc_guid(&ipmidriver.driver, guid);
3129 	else
3130 		old_bmc = ipmi_find_bmc_prod_dev_id(&ipmidriver.driver,
3131 						    id->product_id,
3132 						    id->device_id);
3133 
3134 	/*
3135 	 * If there is already an bmc_device, free the new one,
3136 	 * otherwise register the new BMC device
3137 	 */
3138 	if (old_bmc) {
3139 		bmc = old_bmc;
3140 		/*
3141 		 * Note: old_bmc already has usecount incremented by
3142 		 * the BMC find functions.
3143 		 */
3144 		intf->bmc = old_bmc;
3145 		mutex_lock(&bmc->dyn_mutex);
3146 		list_add_tail(&intf->bmc_link, &bmc->intfs);
3147 		mutex_unlock(&bmc->dyn_mutex);
3148 
3149 		dev_info(intf->si_dev,
3150 			 "interfacing existing BMC (man_id: 0x%6.6x, prod_id: 0x%4.4x, dev_id: 0x%2.2x)\n",
3151 			 bmc->id.manufacturer_id,
3152 			 bmc->id.product_id,
3153 			 bmc->id.device_id);
3154 	} else {
3155 		bmc = kzalloc(sizeof(*bmc), GFP_KERNEL);
3156 		if (!bmc) {
3157 			rv = -ENOMEM;
3158 			goto out;
3159 		}
3160 		INIT_LIST_HEAD(&bmc->intfs);
3161 		mutex_init(&bmc->dyn_mutex);
3162 		INIT_WORK(&bmc->remove_work, cleanup_bmc_work);
3163 
3164 		bmc->id = *id;
3165 		bmc->dyn_id_set = 1;
3166 		bmc->dyn_guid_set = guid_set;
3167 		bmc->guid = *guid;
3168 		bmc->dyn_id_expiry = jiffies + IPMI_DYN_DEV_ID_EXPIRY;
3169 
3170 		bmc->pdev.name = "ipmi_bmc";
3171 
3172 		rv = ida_simple_get(&ipmi_bmc_ida, 0, 0, GFP_KERNEL);
3173 		if (rv < 0) {
3174 			kfree(bmc);
3175 			goto out;
3176 		}
3177 
3178 		bmc->pdev.dev.driver = &ipmidriver.driver;
3179 		bmc->pdev.id = rv;
3180 		bmc->pdev.dev.release = release_bmc_device;
3181 		bmc->pdev.dev.type = &bmc_device_type;
3182 		kref_init(&bmc->usecount);
3183 
3184 		intf->bmc = bmc;
3185 		mutex_lock(&bmc->dyn_mutex);
3186 		list_add_tail(&intf->bmc_link, &bmc->intfs);
3187 		mutex_unlock(&bmc->dyn_mutex);
3188 
3189 		rv = platform_device_register(&bmc->pdev);
3190 		if (rv) {
3191 			dev_err(intf->si_dev,
3192 				"Unable to register bmc device: %d\n",
3193 				rv);
3194 			goto out_list_del;
3195 		}
3196 
3197 		dev_info(intf->si_dev,
3198 			 "Found new BMC (man_id: 0x%6.6x, prod_id: 0x%4.4x, dev_id: 0x%2.2x)\n",
3199 			 bmc->id.manufacturer_id,
3200 			 bmc->id.product_id,
3201 			 bmc->id.device_id);
3202 	}
3203 
3204 	/*
3205 	 * create symlink from system interface device to bmc device
3206 	 * and back.
3207 	 */
3208 	rv = sysfs_create_link(&intf->si_dev->kobj, &bmc->pdev.dev.kobj, "bmc");
3209 	if (rv) {
3210 		dev_err(intf->si_dev, "Unable to create bmc symlink: %d\n", rv);
3211 		goto out_put_bmc;
3212 	}
3213 
3214 	if (intf_num == -1)
3215 		intf_num = intf->intf_num;
3216 	intf->my_dev_name = kasprintf(GFP_KERNEL, "ipmi%d", intf_num);
3217 	if (!intf->my_dev_name) {
3218 		rv = -ENOMEM;
3219 		dev_err(intf->si_dev, "Unable to allocate link from BMC: %d\n",
3220 			rv);
3221 		goto out_unlink1;
3222 	}
3223 
3224 	rv = sysfs_create_link(&bmc->pdev.dev.kobj, &intf->si_dev->kobj,
3225 			       intf->my_dev_name);
3226 	if (rv) {
3227 		dev_err(intf->si_dev, "Unable to create symlink to bmc: %d\n",
3228 			rv);
3229 		goto out_free_my_dev_name;
3230 	}
3231 
3232 	intf->bmc_registered = true;
3233 
3234 out:
3235 	mutex_unlock(&ipmidriver_mutex);
3236 	mutex_lock(&intf->bmc_reg_mutex);
3237 	intf->in_bmc_register = false;
3238 	return rv;
3239 
3240 
3241 out_free_my_dev_name:
3242 	kfree(intf->my_dev_name);
3243 	intf->my_dev_name = NULL;
3244 
3245 out_unlink1:
3246 	sysfs_remove_link(&intf->si_dev->kobj, "bmc");
3247 
3248 out_put_bmc:
3249 	mutex_lock(&bmc->dyn_mutex);
3250 	list_del(&intf->bmc_link);
3251 	mutex_unlock(&bmc->dyn_mutex);
3252 	intf->bmc = &intf->tmp_bmc;
3253 	kref_put(&bmc->usecount, cleanup_bmc_device);
3254 	goto out;
3255 
3256 out_list_del:
3257 	mutex_lock(&bmc->dyn_mutex);
3258 	list_del(&intf->bmc_link);
3259 	mutex_unlock(&bmc->dyn_mutex);
3260 	intf->bmc = &intf->tmp_bmc;
3261 	put_device(&bmc->pdev.dev);
3262 	goto out;
3263 }
3264 
3265 static int
send_guid_cmd(struct ipmi_smi * intf,int chan)3266 send_guid_cmd(struct ipmi_smi *intf, int chan)
3267 {
3268 	struct kernel_ipmi_msg            msg;
3269 	struct ipmi_system_interface_addr si;
3270 
3271 	si.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
3272 	si.channel = IPMI_BMC_CHANNEL;
3273 	si.lun = 0;
3274 
3275 	msg.netfn = IPMI_NETFN_APP_REQUEST;
3276 	msg.cmd = IPMI_GET_DEVICE_GUID_CMD;
3277 	msg.data = NULL;
3278 	msg.data_len = 0;
3279 	return i_ipmi_request(NULL,
3280 			      intf,
3281 			      (struct ipmi_addr *) &si,
3282 			      0,
3283 			      &msg,
3284 			      intf,
3285 			      NULL,
3286 			      NULL,
3287 			      0,
3288 			      intf->addrinfo[0].address,
3289 			      intf->addrinfo[0].lun,
3290 			      -1, 0);
3291 }
3292 
guid_handler(struct ipmi_smi * intf,struct ipmi_recv_msg * msg)3293 static void guid_handler(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
3294 {
3295 	struct bmc_device *bmc = intf->bmc;
3296 
3297 	if ((msg->addr.addr_type != IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
3298 	    || (msg->msg.netfn != IPMI_NETFN_APP_RESPONSE)
3299 	    || (msg->msg.cmd != IPMI_GET_DEVICE_GUID_CMD))
3300 		/* Not for me */
3301 		return;
3302 
3303 	if (msg->msg.data[0] != 0) {
3304 		/* Error from getting the GUID, the BMC doesn't have one. */
3305 		bmc->dyn_guid_set = 0;
3306 		goto out;
3307 	}
3308 
3309 	if (msg->msg.data_len < UUID_SIZE + 1) {
3310 		bmc->dyn_guid_set = 0;
3311 		dev_warn(intf->si_dev,
3312 			 "The GUID response from the BMC was too short, it was %d but should have been %d.  Assuming GUID is not available.\n",
3313 			 msg->msg.data_len, UUID_SIZE + 1);
3314 		goto out;
3315 	}
3316 
3317 	import_guid(&bmc->fetch_guid, msg->msg.data + 1);
3318 	/*
3319 	 * Make sure the guid data is available before setting
3320 	 * dyn_guid_set.
3321 	 */
3322 	smp_wmb();
3323 	bmc->dyn_guid_set = 1;
3324  out:
3325 	wake_up(&intf->waitq);
3326 }
3327 
__get_guid(struct ipmi_smi * intf)3328 static void __get_guid(struct ipmi_smi *intf)
3329 {
3330 	int rv;
3331 	struct bmc_device *bmc = intf->bmc;
3332 
3333 	bmc->dyn_guid_set = 2;
3334 	intf->null_user_handler = guid_handler;
3335 	rv = send_guid_cmd(intf, 0);
3336 	if (rv)
3337 		/* Send failed, no GUID available. */
3338 		bmc->dyn_guid_set = 0;
3339 	else
3340 		wait_event(intf->waitq, bmc->dyn_guid_set != 2);
3341 
3342 	/* dyn_guid_set makes the guid data available. */
3343 	smp_rmb();
3344 
3345 	intf->null_user_handler = NULL;
3346 }
3347 
3348 static int
send_channel_info_cmd(struct ipmi_smi * intf,int chan)3349 send_channel_info_cmd(struct ipmi_smi *intf, int chan)
3350 {
3351 	struct kernel_ipmi_msg            msg;
3352 	unsigned char                     data[1];
3353 	struct ipmi_system_interface_addr si;
3354 
3355 	si.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
3356 	si.channel = IPMI_BMC_CHANNEL;
3357 	si.lun = 0;
3358 
3359 	msg.netfn = IPMI_NETFN_APP_REQUEST;
3360 	msg.cmd = IPMI_GET_CHANNEL_INFO_CMD;
3361 	msg.data = data;
3362 	msg.data_len = 1;
3363 	data[0] = chan;
3364 	return i_ipmi_request(NULL,
3365 			      intf,
3366 			      (struct ipmi_addr *) &si,
3367 			      0,
3368 			      &msg,
3369 			      intf,
3370 			      NULL,
3371 			      NULL,
3372 			      0,
3373 			      intf->addrinfo[0].address,
3374 			      intf->addrinfo[0].lun,
3375 			      -1, 0);
3376 }
3377 
3378 static void
channel_handler(struct ipmi_smi * intf,struct ipmi_recv_msg * msg)3379 channel_handler(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
3380 {
3381 	int rv = 0;
3382 	int ch;
3383 	unsigned int set = intf->curr_working_cset;
3384 	struct ipmi_channel *chans;
3385 
3386 	if ((msg->addr.addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
3387 	    && (msg->msg.netfn == IPMI_NETFN_APP_RESPONSE)
3388 	    && (msg->msg.cmd == IPMI_GET_CHANNEL_INFO_CMD)) {
3389 		/* It's the one we want */
3390 		if (msg->msg.data[0] != 0) {
3391 			/* Got an error from the channel, just go on. */
3392 			if (msg->msg.data[0] == IPMI_INVALID_COMMAND_ERR) {
3393 				/*
3394 				 * If the MC does not support this
3395 				 * command, that is legal.  We just
3396 				 * assume it has one IPMB at channel
3397 				 * zero.
3398 				 */
3399 				intf->wchannels[set].c[0].medium
3400 					= IPMI_CHANNEL_MEDIUM_IPMB;
3401 				intf->wchannels[set].c[0].protocol
3402 					= IPMI_CHANNEL_PROTOCOL_IPMB;
3403 
3404 				intf->channel_list = intf->wchannels + set;
3405 				intf->channels_ready = true;
3406 				wake_up(&intf->waitq);
3407 				goto out;
3408 			}
3409 			goto next_channel;
3410 		}
3411 		if (msg->msg.data_len < 4) {
3412 			/* Message not big enough, just go on. */
3413 			goto next_channel;
3414 		}
3415 		ch = intf->curr_channel;
3416 		chans = intf->wchannels[set].c;
3417 		chans[ch].medium = msg->msg.data[2] & 0x7f;
3418 		chans[ch].protocol = msg->msg.data[3] & 0x1f;
3419 
3420  next_channel:
3421 		intf->curr_channel++;
3422 		if (intf->curr_channel >= IPMI_MAX_CHANNELS) {
3423 			intf->channel_list = intf->wchannels + set;
3424 			intf->channels_ready = true;
3425 			wake_up(&intf->waitq);
3426 		} else {
3427 			intf->channel_list = intf->wchannels + set;
3428 			intf->channels_ready = true;
3429 			rv = send_channel_info_cmd(intf, intf->curr_channel);
3430 		}
3431 
3432 		if (rv) {
3433 			/* Got an error somehow, just give up. */
3434 			dev_warn(intf->si_dev,
3435 				 "Error sending channel information for channel %d: %d\n",
3436 				 intf->curr_channel, rv);
3437 
3438 			intf->channel_list = intf->wchannels + set;
3439 			intf->channels_ready = true;
3440 			wake_up(&intf->waitq);
3441 		}
3442 	}
3443  out:
3444 	return;
3445 }
3446 
3447 /*
3448  * Must be holding intf->bmc_reg_mutex to call this.
3449  */
__scan_channels(struct ipmi_smi * intf,struct ipmi_device_id * id)3450 static int __scan_channels(struct ipmi_smi *intf, struct ipmi_device_id *id)
3451 {
3452 	int rv;
3453 
3454 	if (ipmi_version_major(id) > 1
3455 			|| (ipmi_version_major(id) == 1
3456 			    && ipmi_version_minor(id) >= 5)) {
3457 		unsigned int set;
3458 
3459 		/*
3460 		 * Start scanning the channels to see what is
3461 		 * available.
3462 		 */
3463 		set = !intf->curr_working_cset;
3464 		intf->curr_working_cset = set;
3465 		memset(&intf->wchannels[set], 0,
3466 		       sizeof(struct ipmi_channel_set));
3467 
3468 		intf->null_user_handler = channel_handler;
3469 		intf->curr_channel = 0;
3470 		rv = send_channel_info_cmd(intf, 0);
3471 		if (rv) {
3472 			dev_warn(intf->si_dev,
3473 				 "Error sending channel information for channel 0, %d\n",
3474 				 rv);
3475 			intf->null_user_handler = NULL;
3476 			return -EIO;
3477 		}
3478 
3479 		/* Wait for the channel info to be read. */
3480 		wait_event(intf->waitq, intf->channels_ready);
3481 		intf->null_user_handler = NULL;
3482 	} else {
3483 		unsigned int set = intf->curr_working_cset;
3484 
3485 		/* Assume a single IPMB channel at zero. */
3486 		intf->wchannels[set].c[0].medium = IPMI_CHANNEL_MEDIUM_IPMB;
3487 		intf->wchannels[set].c[0].protocol = IPMI_CHANNEL_PROTOCOL_IPMB;
3488 		intf->channel_list = intf->wchannels + set;
3489 		intf->channels_ready = true;
3490 	}
3491 
3492 	return 0;
3493 }
3494 
ipmi_poll(struct ipmi_smi * intf)3495 static void ipmi_poll(struct ipmi_smi *intf)
3496 {
3497 	if (intf->handlers->poll)
3498 		intf->handlers->poll(intf->send_info);
3499 	/* In case something came in */
3500 	handle_new_recv_msgs(intf);
3501 }
3502 
ipmi_poll_interface(struct ipmi_user * user)3503 void ipmi_poll_interface(struct ipmi_user *user)
3504 {
3505 	ipmi_poll(user->intf);
3506 }
3507 EXPORT_SYMBOL(ipmi_poll_interface);
3508 
nr_users_show(struct device * dev,struct device_attribute * attr,char * buf)3509 static ssize_t nr_users_show(struct device *dev,
3510 			     struct device_attribute *attr,
3511 			     char *buf)
3512 {
3513 	struct ipmi_smi *intf = container_of(attr,
3514 			 struct ipmi_smi, nr_users_devattr);
3515 
3516 	return sysfs_emit(buf, "%d\n", atomic_read(&intf->nr_users));
3517 }
3518 static DEVICE_ATTR_RO(nr_users);
3519 
nr_msgs_show(struct device * dev,struct device_attribute * attr,char * buf)3520 static ssize_t nr_msgs_show(struct device *dev,
3521 			    struct device_attribute *attr,
3522 			    char *buf)
3523 {
3524 	struct ipmi_smi *intf = container_of(attr,
3525 			 struct ipmi_smi, nr_msgs_devattr);
3526 	struct ipmi_user *user;
3527 	int index;
3528 	unsigned int count = 0;
3529 
3530 	index = srcu_read_lock(&intf->users_srcu);
3531 	list_for_each_entry_rcu(user, &intf->users, link)
3532 		count += atomic_read(&user->nr_msgs);
3533 	srcu_read_unlock(&intf->users_srcu, index);
3534 
3535 	return sysfs_emit(buf, "%u\n", count);
3536 }
3537 static DEVICE_ATTR_RO(nr_msgs);
3538 
redo_bmc_reg(struct work_struct * work)3539 static void redo_bmc_reg(struct work_struct *work)
3540 {
3541 	struct ipmi_smi *intf = container_of(work, struct ipmi_smi,
3542 					     bmc_reg_work);
3543 
3544 	if (!intf->in_shutdown)
3545 		bmc_get_device_id(intf, NULL, NULL, NULL, NULL);
3546 
3547 	kref_put(&intf->refcount, intf_free);
3548 }
3549 
ipmi_add_smi(struct module * owner,const struct ipmi_smi_handlers * handlers,void * send_info,struct device * si_dev,unsigned char slave_addr)3550 int ipmi_add_smi(struct module         *owner,
3551 		 const struct ipmi_smi_handlers *handlers,
3552 		 void		       *send_info,
3553 		 struct device         *si_dev,
3554 		 unsigned char         slave_addr)
3555 {
3556 	int              i, j;
3557 	int              rv;
3558 	struct ipmi_smi *intf, *tintf;
3559 	struct list_head *link;
3560 	struct ipmi_device_id id;
3561 
3562 	/*
3563 	 * Make sure the driver is actually initialized, this handles
3564 	 * problems with initialization order.
3565 	 */
3566 	rv = ipmi_init_msghandler();
3567 	if (rv)
3568 		return rv;
3569 
3570 	intf = kzalloc(sizeof(*intf), GFP_KERNEL);
3571 	if (!intf)
3572 		return -ENOMEM;
3573 
3574 	rv = init_srcu_struct(&intf->users_srcu);
3575 	if (rv) {
3576 		kfree(intf);
3577 		return rv;
3578 	}
3579 
3580 	intf->owner = owner;
3581 	intf->bmc = &intf->tmp_bmc;
3582 	INIT_LIST_HEAD(&intf->bmc->intfs);
3583 	mutex_init(&intf->bmc->dyn_mutex);
3584 	INIT_LIST_HEAD(&intf->bmc_link);
3585 	mutex_init(&intf->bmc_reg_mutex);
3586 	intf->intf_num = -1; /* Mark it invalid for now. */
3587 	kref_init(&intf->refcount);
3588 	INIT_WORK(&intf->bmc_reg_work, redo_bmc_reg);
3589 	intf->si_dev = si_dev;
3590 	for (j = 0; j < IPMI_MAX_CHANNELS; j++) {
3591 		intf->addrinfo[j].address = IPMI_BMC_SLAVE_ADDR;
3592 		intf->addrinfo[j].lun = 2;
3593 	}
3594 	if (slave_addr != 0)
3595 		intf->addrinfo[0].address = slave_addr;
3596 	INIT_LIST_HEAD(&intf->users);
3597 	atomic_set(&intf->nr_users, 0);
3598 	intf->handlers = handlers;
3599 	intf->send_info = send_info;
3600 	spin_lock_init(&intf->seq_lock);
3601 	for (j = 0; j < IPMI_IPMB_NUM_SEQ; j++) {
3602 		intf->seq_table[j].inuse = 0;
3603 		intf->seq_table[j].seqid = 0;
3604 	}
3605 	intf->curr_seq = 0;
3606 	spin_lock_init(&intf->waiting_rcv_msgs_lock);
3607 	INIT_LIST_HEAD(&intf->waiting_rcv_msgs);
3608 	tasklet_setup(&intf->recv_tasklet,
3609 		     smi_recv_tasklet);
3610 	atomic_set(&intf->watchdog_pretimeouts_to_deliver, 0);
3611 	spin_lock_init(&intf->xmit_msgs_lock);
3612 	INIT_LIST_HEAD(&intf->xmit_msgs);
3613 	INIT_LIST_HEAD(&intf->hp_xmit_msgs);
3614 	spin_lock_init(&intf->events_lock);
3615 	spin_lock_init(&intf->watch_lock);
3616 	atomic_set(&intf->event_waiters, 0);
3617 	intf->ticks_to_req_ev = IPMI_REQUEST_EV_TIME;
3618 	INIT_LIST_HEAD(&intf->waiting_events);
3619 	intf->waiting_events_count = 0;
3620 	mutex_init(&intf->cmd_rcvrs_mutex);
3621 	spin_lock_init(&intf->maintenance_mode_lock);
3622 	INIT_LIST_HEAD(&intf->cmd_rcvrs);
3623 	init_waitqueue_head(&intf->waitq);
3624 	for (i = 0; i < IPMI_NUM_STATS; i++)
3625 		atomic_set(&intf->stats[i], 0);
3626 
3627 	mutex_lock(&ipmi_interfaces_mutex);
3628 	/* Look for a hole in the numbers. */
3629 	i = 0;
3630 	link = &ipmi_interfaces;
3631 	list_for_each_entry_rcu(tintf, &ipmi_interfaces, link,
3632 				ipmi_interfaces_mutex_held()) {
3633 		if (tintf->intf_num != i) {
3634 			link = &tintf->link;
3635 			break;
3636 		}
3637 		i++;
3638 	}
3639 	/* Add the new interface in numeric order. */
3640 	if (i == 0)
3641 		list_add_rcu(&intf->link, &ipmi_interfaces);
3642 	else
3643 		list_add_tail_rcu(&intf->link, link);
3644 
3645 	rv = handlers->start_processing(send_info, intf);
3646 	if (rv)
3647 		goto out_err;
3648 
3649 	rv = __bmc_get_device_id(intf, NULL, &id, NULL, NULL, i);
3650 	if (rv) {
3651 		dev_err(si_dev, "Unable to get the device id: %d\n", rv);
3652 		goto out_err_started;
3653 	}
3654 
3655 	mutex_lock(&intf->bmc_reg_mutex);
3656 	rv = __scan_channels(intf, &id);
3657 	mutex_unlock(&intf->bmc_reg_mutex);
3658 	if (rv)
3659 		goto out_err_bmc_reg;
3660 
3661 	intf->nr_users_devattr = dev_attr_nr_users;
3662 	sysfs_attr_init(&intf->nr_users_devattr.attr);
3663 	rv = device_create_file(intf->si_dev, &intf->nr_users_devattr);
3664 	if (rv)
3665 		goto out_err_bmc_reg;
3666 
3667 	intf->nr_msgs_devattr = dev_attr_nr_msgs;
3668 	sysfs_attr_init(&intf->nr_msgs_devattr.attr);
3669 	rv = device_create_file(intf->si_dev, &intf->nr_msgs_devattr);
3670 	if (rv) {
3671 		device_remove_file(intf->si_dev, &intf->nr_users_devattr);
3672 		goto out_err_bmc_reg;
3673 	}
3674 
3675 	/*
3676 	 * Keep memory order straight for RCU readers.  Make
3677 	 * sure everything else is committed to memory before
3678 	 * setting intf_num to mark the interface valid.
3679 	 */
3680 	smp_wmb();
3681 	intf->intf_num = i;
3682 	mutex_unlock(&ipmi_interfaces_mutex);
3683 
3684 	/* After this point the interface is legal to use. */
3685 	call_smi_watchers(i, intf->si_dev);
3686 
3687 	return 0;
3688 
3689  out_err_bmc_reg:
3690 	ipmi_bmc_unregister(intf);
3691  out_err_started:
3692 	if (intf->handlers->shutdown)
3693 		intf->handlers->shutdown(intf->send_info);
3694  out_err:
3695 	list_del_rcu(&intf->link);
3696 	mutex_unlock(&ipmi_interfaces_mutex);
3697 	synchronize_srcu(&ipmi_interfaces_srcu);
3698 	cleanup_srcu_struct(&intf->users_srcu);
3699 	kref_put(&intf->refcount, intf_free);
3700 
3701 	return rv;
3702 }
3703 EXPORT_SYMBOL(ipmi_add_smi);
3704 
deliver_smi_err_response(struct ipmi_smi * intf,struct ipmi_smi_msg * msg,unsigned char err)3705 static void deliver_smi_err_response(struct ipmi_smi *intf,
3706 				     struct ipmi_smi_msg *msg,
3707 				     unsigned char err)
3708 {
3709 	int rv;
3710 	msg->rsp[0] = msg->data[0] | 4;
3711 	msg->rsp[1] = msg->data[1];
3712 	msg->rsp[2] = err;
3713 	msg->rsp_size = 3;
3714 
3715 	/* This will never requeue, but it may ask us to free the message. */
3716 	rv = handle_one_recv_msg(intf, msg);
3717 	if (rv == 0)
3718 		ipmi_free_smi_msg(msg);
3719 }
3720 
cleanup_smi_msgs(struct ipmi_smi * intf)3721 static void cleanup_smi_msgs(struct ipmi_smi *intf)
3722 {
3723 	int              i;
3724 	struct seq_table *ent;
3725 	struct ipmi_smi_msg *msg;
3726 	struct list_head *entry;
3727 	struct list_head tmplist;
3728 
3729 	/* Clear out our transmit queues and hold the messages. */
3730 	INIT_LIST_HEAD(&tmplist);
3731 	list_splice_tail(&intf->hp_xmit_msgs, &tmplist);
3732 	list_splice_tail(&intf->xmit_msgs, &tmplist);
3733 
3734 	/* Current message first, to preserve order */
3735 	while (intf->curr_msg && !list_empty(&intf->waiting_rcv_msgs)) {
3736 		/* Wait for the message to clear out. */
3737 		schedule_timeout(1);
3738 	}
3739 
3740 	/* No need for locks, the interface is down. */
3741 
3742 	/*
3743 	 * Return errors for all pending messages in queue and in the
3744 	 * tables waiting for remote responses.
3745 	 */
3746 	while (!list_empty(&tmplist)) {
3747 		entry = tmplist.next;
3748 		list_del(entry);
3749 		msg = list_entry(entry, struct ipmi_smi_msg, link);
3750 		deliver_smi_err_response(intf, msg, IPMI_ERR_UNSPECIFIED);
3751 	}
3752 
3753 	for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++) {
3754 		ent = &intf->seq_table[i];
3755 		if (!ent->inuse)
3756 			continue;
3757 		deliver_err_response(intf, ent->recv_msg, IPMI_ERR_UNSPECIFIED);
3758 	}
3759 }
3760 
ipmi_unregister_smi(struct ipmi_smi * intf)3761 void ipmi_unregister_smi(struct ipmi_smi *intf)
3762 {
3763 	struct ipmi_smi_watcher *w;
3764 	int intf_num, index;
3765 
3766 	if (!intf)
3767 		return;
3768 	intf_num = intf->intf_num;
3769 	mutex_lock(&ipmi_interfaces_mutex);
3770 	intf->intf_num = -1;
3771 	intf->in_shutdown = true;
3772 	list_del_rcu(&intf->link);
3773 	mutex_unlock(&ipmi_interfaces_mutex);
3774 	synchronize_srcu(&ipmi_interfaces_srcu);
3775 
3776 	/* At this point no users can be added to the interface. */
3777 
3778 	device_remove_file(intf->si_dev, &intf->nr_msgs_devattr);
3779 	device_remove_file(intf->si_dev, &intf->nr_users_devattr);
3780 
3781 	/*
3782 	 * Call all the watcher interfaces to tell them that
3783 	 * an interface is going away.
3784 	 */
3785 	mutex_lock(&smi_watchers_mutex);
3786 	list_for_each_entry(w, &smi_watchers, link)
3787 		w->smi_gone(intf_num);
3788 	mutex_unlock(&smi_watchers_mutex);
3789 
3790 	index = srcu_read_lock(&intf->users_srcu);
3791 	while (!list_empty(&intf->users)) {
3792 		struct ipmi_user *user =
3793 			container_of(list_next_rcu(&intf->users),
3794 				     struct ipmi_user, link);
3795 
3796 		_ipmi_destroy_user(user);
3797 	}
3798 	srcu_read_unlock(&intf->users_srcu, index);
3799 
3800 	if (intf->handlers->shutdown)
3801 		intf->handlers->shutdown(intf->send_info);
3802 
3803 	cleanup_smi_msgs(intf);
3804 
3805 	ipmi_bmc_unregister(intf);
3806 
3807 	cleanup_srcu_struct(&intf->users_srcu);
3808 	kref_put(&intf->refcount, intf_free);
3809 }
3810 EXPORT_SYMBOL(ipmi_unregister_smi);
3811 
handle_ipmb_get_msg_rsp(struct ipmi_smi * intf,struct ipmi_smi_msg * msg)3812 static int handle_ipmb_get_msg_rsp(struct ipmi_smi *intf,
3813 				   struct ipmi_smi_msg *msg)
3814 {
3815 	struct ipmi_ipmb_addr ipmb_addr;
3816 	struct ipmi_recv_msg  *recv_msg;
3817 
3818 	/*
3819 	 * This is 11, not 10, because the response must contain a
3820 	 * completion code.
3821 	 */
3822 	if (msg->rsp_size < 11) {
3823 		/* Message not big enough, just ignore it. */
3824 		ipmi_inc_stat(intf, invalid_ipmb_responses);
3825 		return 0;
3826 	}
3827 
3828 	if (msg->rsp[2] != 0) {
3829 		/* An error getting the response, just ignore it. */
3830 		return 0;
3831 	}
3832 
3833 	ipmb_addr.addr_type = IPMI_IPMB_ADDR_TYPE;
3834 	ipmb_addr.slave_addr = msg->rsp[6];
3835 	ipmb_addr.channel = msg->rsp[3] & 0x0f;
3836 	ipmb_addr.lun = msg->rsp[7] & 3;
3837 
3838 	/*
3839 	 * It's a response from a remote entity.  Look up the sequence
3840 	 * number and handle the response.
3841 	 */
3842 	if (intf_find_seq(intf,
3843 			  msg->rsp[7] >> 2,
3844 			  msg->rsp[3] & 0x0f,
3845 			  msg->rsp[8],
3846 			  (msg->rsp[4] >> 2) & (~1),
3847 			  (struct ipmi_addr *) &ipmb_addr,
3848 			  &recv_msg)) {
3849 		/*
3850 		 * We were unable to find the sequence number,
3851 		 * so just nuke the message.
3852 		 */
3853 		ipmi_inc_stat(intf, unhandled_ipmb_responses);
3854 		return 0;
3855 	}
3856 
3857 	memcpy(recv_msg->msg_data, &msg->rsp[9], msg->rsp_size - 9);
3858 	/*
3859 	 * The other fields matched, so no need to set them, except
3860 	 * for netfn, which needs to be the response that was
3861 	 * returned, not the request value.
3862 	 */
3863 	recv_msg->msg.netfn = msg->rsp[4] >> 2;
3864 	recv_msg->msg.data = recv_msg->msg_data;
3865 	recv_msg->msg.data_len = msg->rsp_size - 10;
3866 	recv_msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
3867 	if (deliver_response(intf, recv_msg))
3868 		ipmi_inc_stat(intf, unhandled_ipmb_responses);
3869 	else
3870 		ipmi_inc_stat(intf, handled_ipmb_responses);
3871 
3872 	return 0;
3873 }
3874 
handle_ipmb_get_msg_cmd(struct ipmi_smi * intf,struct ipmi_smi_msg * msg)3875 static int handle_ipmb_get_msg_cmd(struct ipmi_smi *intf,
3876 				   struct ipmi_smi_msg *msg)
3877 {
3878 	struct cmd_rcvr          *rcvr;
3879 	int                      rv = 0;
3880 	unsigned char            netfn;
3881 	unsigned char            cmd;
3882 	unsigned char            chan;
3883 	struct ipmi_user         *user = NULL;
3884 	struct ipmi_ipmb_addr    *ipmb_addr;
3885 	struct ipmi_recv_msg     *recv_msg;
3886 
3887 	if (msg->rsp_size < 10) {
3888 		/* Message not big enough, just ignore it. */
3889 		ipmi_inc_stat(intf, invalid_commands);
3890 		return 0;
3891 	}
3892 
3893 	if (msg->rsp[2] != 0) {
3894 		/* An error getting the response, just ignore it. */
3895 		return 0;
3896 	}
3897 
3898 	netfn = msg->rsp[4] >> 2;
3899 	cmd = msg->rsp[8];
3900 	chan = msg->rsp[3] & 0xf;
3901 
3902 	rcu_read_lock();
3903 	rcvr = find_cmd_rcvr(intf, netfn, cmd, chan);
3904 	if (rcvr) {
3905 		user = rcvr->user;
3906 		kref_get(&user->refcount);
3907 	} else
3908 		user = NULL;
3909 	rcu_read_unlock();
3910 
3911 	if (user == NULL) {
3912 		/* We didn't find a user, deliver an error response. */
3913 		ipmi_inc_stat(intf, unhandled_commands);
3914 
3915 		msg->data[0] = (IPMI_NETFN_APP_REQUEST << 2);
3916 		msg->data[1] = IPMI_SEND_MSG_CMD;
3917 		msg->data[2] = msg->rsp[3];
3918 		msg->data[3] = msg->rsp[6];
3919 		msg->data[4] = ((netfn + 1) << 2) | (msg->rsp[7] & 0x3);
3920 		msg->data[5] = ipmb_checksum(&msg->data[3], 2);
3921 		msg->data[6] = intf->addrinfo[msg->rsp[3] & 0xf].address;
3922 		/* rqseq/lun */
3923 		msg->data[7] = (msg->rsp[7] & 0xfc) | (msg->rsp[4] & 0x3);
3924 		msg->data[8] = msg->rsp[8]; /* cmd */
3925 		msg->data[9] = IPMI_INVALID_CMD_COMPLETION_CODE;
3926 		msg->data[10] = ipmb_checksum(&msg->data[6], 4);
3927 		msg->data_size = 11;
3928 
3929 		dev_dbg(intf->si_dev, "Invalid command: %*ph\n",
3930 			msg->data_size, msg->data);
3931 
3932 		rcu_read_lock();
3933 		if (!intf->in_shutdown) {
3934 			smi_send(intf, intf->handlers, msg, 0);
3935 			/*
3936 			 * We used the message, so return the value
3937 			 * that causes it to not be freed or
3938 			 * queued.
3939 			 */
3940 			rv = -1;
3941 		}
3942 		rcu_read_unlock();
3943 	} else {
3944 		recv_msg = ipmi_alloc_recv_msg();
3945 		if (!recv_msg) {
3946 			/*
3947 			 * We couldn't allocate memory for the
3948 			 * message, so requeue it for handling
3949 			 * later.
3950 			 */
3951 			rv = 1;
3952 			kref_put(&user->refcount, free_user);
3953 		} else {
3954 			/* Extract the source address from the data. */
3955 			ipmb_addr = (struct ipmi_ipmb_addr *) &recv_msg->addr;
3956 			ipmb_addr->addr_type = IPMI_IPMB_ADDR_TYPE;
3957 			ipmb_addr->slave_addr = msg->rsp[6];
3958 			ipmb_addr->lun = msg->rsp[7] & 3;
3959 			ipmb_addr->channel = msg->rsp[3] & 0xf;
3960 
3961 			/*
3962 			 * Extract the rest of the message information
3963 			 * from the IPMB header.
3964 			 */
3965 			recv_msg->user = user;
3966 			recv_msg->recv_type = IPMI_CMD_RECV_TYPE;
3967 			recv_msg->msgid = msg->rsp[7] >> 2;
3968 			recv_msg->msg.netfn = msg->rsp[4] >> 2;
3969 			recv_msg->msg.cmd = msg->rsp[8];
3970 			recv_msg->msg.data = recv_msg->msg_data;
3971 
3972 			/*
3973 			 * We chop off 10, not 9 bytes because the checksum
3974 			 * at the end also needs to be removed.
3975 			 */
3976 			recv_msg->msg.data_len = msg->rsp_size - 10;
3977 			memcpy(recv_msg->msg_data, &msg->rsp[9],
3978 			       msg->rsp_size - 10);
3979 			if (deliver_response(intf, recv_msg))
3980 				ipmi_inc_stat(intf, unhandled_commands);
3981 			else
3982 				ipmi_inc_stat(intf, handled_commands);
3983 		}
3984 	}
3985 
3986 	return rv;
3987 }
3988 
handle_ipmb_direct_rcv_cmd(struct ipmi_smi * intf,struct ipmi_smi_msg * msg)3989 static int handle_ipmb_direct_rcv_cmd(struct ipmi_smi *intf,
3990 				      struct ipmi_smi_msg *msg)
3991 {
3992 	struct cmd_rcvr          *rcvr;
3993 	int                      rv = 0;
3994 	struct ipmi_user         *user = NULL;
3995 	struct ipmi_ipmb_direct_addr *daddr;
3996 	struct ipmi_recv_msg     *recv_msg;
3997 	unsigned char netfn = msg->rsp[0] >> 2;
3998 	unsigned char cmd = msg->rsp[3];
3999 
4000 	rcu_read_lock();
4001 	/* We always use channel 0 for direct messages. */
4002 	rcvr = find_cmd_rcvr(intf, netfn, cmd, 0);
4003 	if (rcvr) {
4004 		user = rcvr->user;
4005 		kref_get(&user->refcount);
4006 	} else
4007 		user = NULL;
4008 	rcu_read_unlock();
4009 
4010 	if (user == NULL) {
4011 		/* We didn't find a user, deliver an error response. */
4012 		ipmi_inc_stat(intf, unhandled_commands);
4013 
4014 		msg->data[0] = (netfn + 1) << 2;
4015 		msg->data[0] |= msg->rsp[2] & 0x3; /* rqLUN */
4016 		msg->data[1] = msg->rsp[1]; /* Addr */
4017 		msg->data[2] = msg->rsp[2] & ~0x3; /* rqSeq */
4018 		msg->data[2] |= msg->rsp[0] & 0x3; /* rsLUN */
4019 		msg->data[3] = cmd;
4020 		msg->data[4] = IPMI_INVALID_CMD_COMPLETION_CODE;
4021 		msg->data_size = 5;
4022 
4023 		rcu_read_lock();
4024 		if (!intf->in_shutdown) {
4025 			smi_send(intf, intf->handlers, msg, 0);
4026 			/*
4027 			 * We used the message, so return the value
4028 			 * that causes it to not be freed or
4029 			 * queued.
4030 			 */
4031 			rv = -1;
4032 		}
4033 		rcu_read_unlock();
4034 	} else {
4035 		recv_msg = ipmi_alloc_recv_msg();
4036 		if (!recv_msg) {
4037 			/*
4038 			 * We couldn't allocate memory for the
4039 			 * message, so requeue it for handling
4040 			 * later.
4041 			 */
4042 			rv = 1;
4043 			kref_put(&user->refcount, free_user);
4044 		} else {
4045 			/* Extract the source address from the data. */
4046 			daddr = (struct ipmi_ipmb_direct_addr *)&recv_msg->addr;
4047 			daddr->addr_type = IPMI_IPMB_DIRECT_ADDR_TYPE;
4048 			daddr->channel = 0;
4049 			daddr->slave_addr = msg->rsp[1];
4050 			daddr->rs_lun = msg->rsp[0] & 3;
4051 			daddr->rq_lun = msg->rsp[2] & 3;
4052 
4053 			/*
4054 			 * Extract the rest of the message information
4055 			 * from the IPMB header.
4056 			 */
4057 			recv_msg->user = user;
4058 			recv_msg->recv_type = IPMI_CMD_RECV_TYPE;
4059 			recv_msg->msgid = (msg->rsp[2] >> 2);
4060 			recv_msg->msg.netfn = msg->rsp[0] >> 2;
4061 			recv_msg->msg.cmd = msg->rsp[3];
4062 			recv_msg->msg.data = recv_msg->msg_data;
4063 
4064 			recv_msg->msg.data_len = msg->rsp_size - 4;
4065 			memcpy(recv_msg->msg_data, msg->rsp + 4,
4066 			       msg->rsp_size - 4);
4067 			if (deliver_response(intf, recv_msg))
4068 				ipmi_inc_stat(intf, unhandled_commands);
4069 			else
4070 				ipmi_inc_stat(intf, handled_commands);
4071 		}
4072 	}
4073 
4074 	return rv;
4075 }
4076 
handle_ipmb_direct_rcv_rsp(struct ipmi_smi * intf,struct ipmi_smi_msg * msg)4077 static int handle_ipmb_direct_rcv_rsp(struct ipmi_smi *intf,
4078 				      struct ipmi_smi_msg *msg)
4079 {
4080 	struct ipmi_recv_msg *recv_msg;
4081 	struct ipmi_ipmb_direct_addr *daddr;
4082 
4083 	recv_msg = msg->user_data;
4084 	if (recv_msg == NULL) {
4085 		dev_warn(intf->si_dev,
4086 			 "IPMI direct message received with no owner. This could be because of a malformed message, or because of a hardware error.  Contact your hardware vendor for assistance.\n");
4087 		return 0;
4088 	}
4089 
4090 	recv_msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
4091 	recv_msg->msgid = msg->msgid;
4092 	daddr = (struct ipmi_ipmb_direct_addr *) &recv_msg->addr;
4093 	daddr->addr_type = IPMI_IPMB_DIRECT_ADDR_TYPE;
4094 	daddr->channel = 0;
4095 	daddr->slave_addr = msg->rsp[1];
4096 	daddr->rq_lun = msg->rsp[0] & 3;
4097 	daddr->rs_lun = msg->rsp[2] & 3;
4098 	recv_msg->msg.netfn = msg->rsp[0] >> 2;
4099 	recv_msg->msg.cmd = msg->rsp[3];
4100 	memcpy(recv_msg->msg_data, &msg->rsp[4], msg->rsp_size - 4);
4101 	recv_msg->msg.data = recv_msg->msg_data;
4102 	recv_msg->msg.data_len = msg->rsp_size - 4;
4103 	deliver_local_response(intf, recv_msg);
4104 
4105 	return 0;
4106 }
4107 
handle_lan_get_msg_rsp(struct ipmi_smi * intf,struct ipmi_smi_msg * msg)4108 static int handle_lan_get_msg_rsp(struct ipmi_smi *intf,
4109 				  struct ipmi_smi_msg *msg)
4110 {
4111 	struct ipmi_lan_addr  lan_addr;
4112 	struct ipmi_recv_msg  *recv_msg;
4113 
4114 
4115 	/*
4116 	 * This is 13, not 12, because the response must contain a
4117 	 * completion code.
4118 	 */
4119 	if (msg->rsp_size < 13) {
4120 		/* Message not big enough, just ignore it. */
4121 		ipmi_inc_stat(intf, invalid_lan_responses);
4122 		return 0;
4123 	}
4124 
4125 	if (msg->rsp[2] != 0) {
4126 		/* An error getting the response, just ignore it. */
4127 		return 0;
4128 	}
4129 
4130 	lan_addr.addr_type = IPMI_LAN_ADDR_TYPE;
4131 	lan_addr.session_handle = msg->rsp[4];
4132 	lan_addr.remote_SWID = msg->rsp[8];
4133 	lan_addr.local_SWID = msg->rsp[5];
4134 	lan_addr.channel = msg->rsp[3] & 0x0f;
4135 	lan_addr.privilege = msg->rsp[3] >> 4;
4136 	lan_addr.lun = msg->rsp[9] & 3;
4137 
4138 	/*
4139 	 * It's a response from a remote entity.  Look up the sequence
4140 	 * number and handle the response.
4141 	 */
4142 	if (intf_find_seq(intf,
4143 			  msg->rsp[9] >> 2,
4144 			  msg->rsp[3] & 0x0f,
4145 			  msg->rsp[10],
4146 			  (msg->rsp[6] >> 2) & (~1),
4147 			  (struct ipmi_addr *) &lan_addr,
4148 			  &recv_msg)) {
4149 		/*
4150 		 * We were unable to find the sequence number,
4151 		 * so just nuke the message.
4152 		 */
4153 		ipmi_inc_stat(intf, unhandled_lan_responses);
4154 		return 0;
4155 	}
4156 
4157 	memcpy(recv_msg->msg_data, &msg->rsp[11], msg->rsp_size - 11);
4158 	/*
4159 	 * The other fields matched, so no need to set them, except
4160 	 * for netfn, which needs to be the response that was
4161 	 * returned, not the request value.
4162 	 */
4163 	recv_msg->msg.netfn = msg->rsp[6] >> 2;
4164 	recv_msg->msg.data = recv_msg->msg_data;
4165 	recv_msg->msg.data_len = msg->rsp_size - 12;
4166 	recv_msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
4167 	if (deliver_response(intf, recv_msg))
4168 		ipmi_inc_stat(intf, unhandled_lan_responses);
4169 	else
4170 		ipmi_inc_stat(intf, handled_lan_responses);
4171 
4172 	return 0;
4173 }
4174 
handle_lan_get_msg_cmd(struct ipmi_smi * intf,struct ipmi_smi_msg * msg)4175 static int handle_lan_get_msg_cmd(struct ipmi_smi *intf,
4176 				  struct ipmi_smi_msg *msg)
4177 {
4178 	struct cmd_rcvr          *rcvr;
4179 	int                      rv = 0;
4180 	unsigned char            netfn;
4181 	unsigned char            cmd;
4182 	unsigned char            chan;
4183 	struct ipmi_user         *user = NULL;
4184 	struct ipmi_lan_addr     *lan_addr;
4185 	struct ipmi_recv_msg     *recv_msg;
4186 
4187 	if (msg->rsp_size < 12) {
4188 		/* Message not big enough, just ignore it. */
4189 		ipmi_inc_stat(intf, invalid_commands);
4190 		return 0;
4191 	}
4192 
4193 	if (msg->rsp[2] != 0) {
4194 		/* An error getting the response, just ignore it. */
4195 		return 0;
4196 	}
4197 
4198 	netfn = msg->rsp[6] >> 2;
4199 	cmd = msg->rsp[10];
4200 	chan = msg->rsp[3] & 0xf;
4201 
4202 	rcu_read_lock();
4203 	rcvr = find_cmd_rcvr(intf, netfn, cmd, chan);
4204 	if (rcvr) {
4205 		user = rcvr->user;
4206 		kref_get(&user->refcount);
4207 	} else
4208 		user = NULL;
4209 	rcu_read_unlock();
4210 
4211 	if (user == NULL) {
4212 		/* We didn't find a user, just give up. */
4213 		ipmi_inc_stat(intf, unhandled_commands);
4214 
4215 		/*
4216 		 * Don't do anything with these messages, just allow
4217 		 * them to be freed.
4218 		 */
4219 		rv = 0;
4220 	} else {
4221 		recv_msg = ipmi_alloc_recv_msg();
4222 		if (!recv_msg) {
4223 			/*
4224 			 * We couldn't allocate memory for the
4225 			 * message, so requeue it for handling later.
4226 			 */
4227 			rv = 1;
4228 			kref_put(&user->refcount, free_user);
4229 		} else {
4230 			/* Extract the source address from the data. */
4231 			lan_addr = (struct ipmi_lan_addr *) &recv_msg->addr;
4232 			lan_addr->addr_type = IPMI_LAN_ADDR_TYPE;
4233 			lan_addr->session_handle = msg->rsp[4];
4234 			lan_addr->remote_SWID = msg->rsp[8];
4235 			lan_addr->local_SWID = msg->rsp[5];
4236 			lan_addr->lun = msg->rsp[9] & 3;
4237 			lan_addr->channel = msg->rsp[3] & 0xf;
4238 			lan_addr->privilege = msg->rsp[3] >> 4;
4239 
4240 			/*
4241 			 * Extract the rest of the message information
4242 			 * from the IPMB header.
4243 			 */
4244 			recv_msg->user = user;
4245 			recv_msg->recv_type = IPMI_CMD_RECV_TYPE;
4246 			recv_msg->msgid = msg->rsp[9] >> 2;
4247 			recv_msg->msg.netfn = msg->rsp[6] >> 2;
4248 			recv_msg->msg.cmd = msg->rsp[10];
4249 			recv_msg->msg.data = recv_msg->msg_data;
4250 
4251 			/*
4252 			 * We chop off 12, not 11 bytes because the checksum
4253 			 * at the end also needs to be removed.
4254 			 */
4255 			recv_msg->msg.data_len = msg->rsp_size - 12;
4256 			memcpy(recv_msg->msg_data, &msg->rsp[11],
4257 			       msg->rsp_size - 12);
4258 			if (deliver_response(intf, recv_msg))
4259 				ipmi_inc_stat(intf, unhandled_commands);
4260 			else
4261 				ipmi_inc_stat(intf, handled_commands);
4262 		}
4263 	}
4264 
4265 	return rv;
4266 }
4267 
4268 /*
4269  * This routine will handle "Get Message" command responses with
4270  * channels that use an OEM Medium. The message format belongs to
4271  * the OEM.  See IPMI 2.0 specification, Chapter 6 and
4272  * Chapter 22, sections 22.6 and 22.24 for more details.
4273  */
handle_oem_get_msg_cmd(struct ipmi_smi * intf,struct ipmi_smi_msg * msg)4274 static int handle_oem_get_msg_cmd(struct ipmi_smi *intf,
4275 				  struct ipmi_smi_msg *msg)
4276 {
4277 	struct cmd_rcvr       *rcvr;
4278 	int                   rv = 0;
4279 	unsigned char         netfn;
4280 	unsigned char         cmd;
4281 	unsigned char         chan;
4282 	struct ipmi_user *user = NULL;
4283 	struct ipmi_system_interface_addr *smi_addr;
4284 	struct ipmi_recv_msg  *recv_msg;
4285 
4286 	/*
4287 	 * We expect the OEM SW to perform error checking
4288 	 * so we just do some basic sanity checks
4289 	 */
4290 	if (msg->rsp_size < 4) {
4291 		/* Message not big enough, just ignore it. */
4292 		ipmi_inc_stat(intf, invalid_commands);
4293 		return 0;
4294 	}
4295 
4296 	if (msg->rsp[2] != 0) {
4297 		/* An error getting the response, just ignore it. */
4298 		return 0;
4299 	}
4300 
4301 	/*
4302 	 * This is an OEM Message so the OEM needs to know how
4303 	 * handle the message. We do no interpretation.
4304 	 */
4305 	netfn = msg->rsp[0] >> 2;
4306 	cmd = msg->rsp[1];
4307 	chan = msg->rsp[3] & 0xf;
4308 
4309 	rcu_read_lock();
4310 	rcvr = find_cmd_rcvr(intf, netfn, cmd, chan);
4311 	if (rcvr) {
4312 		user = rcvr->user;
4313 		kref_get(&user->refcount);
4314 	} else
4315 		user = NULL;
4316 	rcu_read_unlock();
4317 
4318 	if (user == NULL) {
4319 		/* We didn't find a user, just give up. */
4320 		ipmi_inc_stat(intf, unhandled_commands);
4321 
4322 		/*
4323 		 * Don't do anything with these messages, just allow
4324 		 * them to be freed.
4325 		 */
4326 
4327 		rv = 0;
4328 	} else {
4329 		recv_msg = ipmi_alloc_recv_msg();
4330 		if (!recv_msg) {
4331 			/*
4332 			 * We couldn't allocate memory for the
4333 			 * message, so requeue it for handling
4334 			 * later.
4335 			 */
4336 			rv = 1;
4337 			kref_put(&user->refcount, free_user);
4338 		} else {
4339 			/*
4340 			 * OEM Messages are expected to be delivered via
4341 			 * the system interface to SMS software.  We might
4342 			 * need to visit this again depending on OEM
4343 			 * requirements
4344 			 */
4345 			smi_addr = ((struct ipmi_system_interface_addr *)
4346 				    &recv_msg->addr);
4347 			smi_addr->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
4348 			smi_addr->channel = IPMI_BMC_CHANNEL;
4349 			smi_addr->lun = msg->rsp[0] & 3;
4350 
4351 			recv_msg->user = user;
4352 			recv_msg->user_msg_data = NULL;
4353 			recv_msg->recv_type = IPMI_OEM_RECV_TYPE;
4354 			recv_msg->msg.netfn = msg->rsp[0] >> 2;
4355 			recv_msg->msg.cmd = msg->rsp[1];
4356 			recv_msg->msg.data = recv_msg->msg_data;
4357 
4358 			/*
4359 			 * The message starts at byte 4 which follows the
4360 			 * Channel Byte in the "GET MESSAGE" command
4361 			 */
4362 			recv_msg->msg.data_len = msg->rsp_size - 4;
4363 			memcpy(recv_msg->msg_data, &msg->rsp[4],
4364 			       msg->rsp_size - 4);
4365 			if (deliver_response(intf, recv_msg))
4366 				ipmi_inc_stat(intf, unhandled_commands);
4367 			else
4368 				ipmi_inc_stat(intf, handled_commands);
4369 		}
4370 	}
4371 
4372 	return rv;
4373 }
4374 
copy_event_into_recv_msg(struct ipmi_recv_msg * recv_msg,struct ipmi_smi_msg * msg)4375 static void copy_event_into_recv_msg(struct ipmi_recv_msg *recv_msg,
4376 				     struct ipmi_smi_msg  *msg)
4377 {
4378 	struct ipmi_system_interface_addr *smi_addr;
4379 
4380 	recv_msg->msgid = 0;
4381 	smi_addr = (struct ipmi_system_interface_addr *) &recv_msg->addr;
4382 	smi_addr->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
4383 	smi_addr->channel = IPMI_BMC_CHANNEL;
4384 	smi_addr->lun = msg->rsp[0] & 3;
4385 	recv_msg->recv_type = IPMI_ASYNC_EVENT_RECV_TYPE;
4386 	recv_msg->msg.netfn = msg->rsp[0] >> 2;
4387 	recv_msg->msg.cmd = msg->rsp[1];
4388 	memcpy(recv_msg->msg_data, &msg->rsp[3], msg->rsp_size - 3);
4389 	recv_msg->msg.data = recv_msg->msg_data;
4390 	recv_msg->msg.data_len = msg->rsp_size - 3;
4391 }
4392 
handle_read_event_rsp(struct ipmi_smi * intf,struct ipmi_smi_msg * msg)4393 static int handle_read_event_rsp(struct ipmi_smi *intf,
4394 				 struct ipmi_smi_msg *msg)
4395 {
4396 	struct ipmi_recv_msg *recv_msg, *recv_msg2;
4397 	struct list_head     msgs;
4398 	struct ipmi_user     *user;
4399 	int rv = 0, deliver_count = 0, index;
4400 	unsigned long        flags;
4401 
4402 	if (msg->rsp_size < 19) {
4403 		/* Message is too small to be an IPMB event. */
4404 		ipmi_inc_stat(intf, invalid_events);
4405 		return 0;
4406 	}
4407 
4408 	if (msg->rsp[2] != 0) {
4409 		/* An error getting the event, just ignore it. */
4410 		return 0;
4411 	}
4412 
4413 	INIT_LIST_HEAD(&msgs);
4414 
4415 	spin_lock_irqsave(&intf->events_lock, flags);
4416 
4417 	ipmi_inc_stat(intf, events);
4418 
4419 	/*
4420 	 * Allocate and fill in one message for every user that is
4421 	 * getting events.
4422 	 */
4423 	index = srcu_read_lock(&intf->users_srcu);
4424 	list_for_each_entry_rcu(user, &intf->users, link) {
4425 		if (!user->gets_events)
4426 			continue;
4427 
4428 		recv_msg = ipmi_alloc_recv_msg();
4429 		if (!recv_msg) {
4430 			rcu_read_unlock();
4431 			list_for_each_entry_safe(recv_msg, recv_msg2, &msgs,
4432 						 link) {
4433 				list_del(&recv_msg->link);
4434 				ipmi_free_recv_msg(recv_msg);
4435 			}
4436 			/*
4437 			 * We couldn't allocate memory for the
4438 			 * message, so requeue it for handling
4439 			 * later.
4440 			 */
4441 			rv = 1;
4442 			goto out;
4443 		}
4444 
4445 		deliver_count++;
4446 
4447 		copy_event_into_recv_msg(recv_msg, msg);
4448 		recv_msg->user = user;
4449 		kref_get(&user->refcount);
4450 		list_add_tail(&recv_msg->link, &msgs);
4451 	}
4452 	srcu_read_unlock(&intf->users_srcu, index);
4453 
4454 	if (deliver_count) {
4455 		/* Now deliver all the messages. */
4456 		list_for_each_entry_safe(recv_msg, recv_msg2, &msgs, link) {
4457 			list_del(&recv_msg->link);
4458 			deliver_local_response(intf, recv_msg);
4459 		}
4460 	} else if (intf->waiting_events_count < MAX_EVENTS_IN_QUEUE) {
4461 		/*
4462 		 * No one to receive the message, put it in queue if there's
4463 		 * not already too many things in the queue.
4464 		 */
4465 		recv_msg = ipmi_alloc_recv_msg();
4466 		if (!recv_msg) {
4467 			/*
4468 			 * We couldn't allocate memory for the
4469 			 * message, so requeue it for handling
4470 			 * later.
4471 			 */
4472 			rv = 1;
4473 			goto out;
4474 		}
4475 
4476 		copy_event_into_recv_msg(recv_msg, msg);
4477 		list_add_tail(&recv_msg->link, &intf->waiting_events);
4478 		intf->waiting_events_count++;
4479 	} else if (!intf->event_msg_printed) {
4480 		/*
4481 		 * There's too many things in the queue, discard this
4482 		 * message.
4483 		 */
4484 		dev_warn(intf->si_dev,
4485 			 "Event queue full, discarding incoming events\n");
4486 		intf->event_msg_printed = 1;
4487 	}
4488 
4489  out:
4490 	spin_unlock_irqrestore(&intf->events_lock, flags);
4491 
4492 	return rv;
4493 }
4494 
handle_bmc_rsp(struct ipmi_smi * intf,struct ipmi_smi_msg * msg)4495 static int handle_bmc_rsp(struct ipmi_smi *intf,
4496 			  struct ipmi_smi_msg *msg)
4497 {
4498 	struct ipmi_recv_msg *recv_msg;
4499 	struct ipmi_system_interface_addr *smi_addr;
4500 
4501 	recv_msg = msg->user_data;
4502 	if (recv_msg == NULL) {
4503 		dev_warn(intf->si_dev,
4504 			 "IPMI SMI message received with no owner. This could be because of a malformed message, or because of a hardware error.  Contact your hardware vendor for assistance.\n");
4505 		return 0;
4506 	}
4507 
4508 	recv_msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
4509 	recv_msg->msgid = msg->msgid;
4510 	smi_addr = ((struct ipmi_system_interface_addr *)
4511 		    &recv_msg->addr);
4512 	smi_addr->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
4513 	smi_addr->channel = IPMI_BMC_CHANNEL;
4514 	smi_addr->lun = msg->rsp[0] & 3;
4515 	recv_msg->msg.netfn = msg->rsp[0] >> 2;
4516 	recv_msg->msg.cmd = msg->rsp[1];
4517 	memcpy(recv_msg->msg_data, &msg->rsp[2], msg->rsp_size - 2);
4518 	recv_msg->msg.data = recv_msg->msg_data;
4519 	recv_msg->msg.data_len = msg->rsp_size - 2;
4520 	deliver_local_response(intf, recv_msg);
4521 
4522 	return 0;
4523 }
4524 
4525 /*
4526  * Handle a received message.  Return 1 if the message should be requeued,
4527  * 0 if the message should be freed, or -1 if the message should not
4528  * be freed or requeued.
4529  */
handle_one_recv_msg(struct ipmi_smi * intf,struct ipmi_smi_msg * msg)4530 static int handle_one_recv_msg(struct ipmi_smi *intf,
4531 			       struct ipmi_smi_msg *msg)
4532 {
4533 	int requeue = 0;
4534 	int chan;
4535 	unsigned char cc;
4536 	bool is_cmd = !((msg->rsp[0] >> 2) & 1);
4537 
4538 	dev_dbg(intf->si_dev, "Recv: %*ph\n", msg->rsp_size, msg->rsp);
4539 
4540 	if (msg->rsp_size < 2) {
4541 		/* Message is too small to be correct. */
4542 		dev_warn(intf->si_dev,
4543 			 "BMC returned too small a message for netfn %x cmd %x, got %d bytes\n",
4544 			 (msg->data[0] >> 2) | 1, msg->data[1], msg->rsp_size);
4545 
4546 return_unspecified:
4547 		/* Generate an error response for the message. */
4548 		msg->rsp[0] = msg->data[0] | (1 << 2);
4549 		msg->rsp[1] = msg->data[1];
4550 		msg->rsp[2] = IPMI_ERR_UNSPECIFIED;
4551 		msg->rsp_size = 3;
4552 	} else if (msg->type == IPMI_SMI_MSG_TYPE_IPMB_DIRECT) {
4553 		/* commands must have at least 4 bytes, responses 5. */
4554 		if (is_cmd && (msg->rsp_size < 4)) {
4555 			ipmi_inc_stat(intf, invalid_commands);
4556 			goto out;
4557 		}
4558 		if (!is_cmd && (msg->rsp_size < 5)) {
4559 			ipmi_inc_stat(intf, invalid_ipmb_responses);
4560 			/* Construct a valid error response. */
4561 			msg->rsp[0] = msg->data[0] & 0xfc; /* NetFN */
4562 			msg->rsp[0] |= (1 << 2); /* Make it a response */
4563 			msg->rsp[0] |= msg->data[2] & 3; /* rqLUN */
4564 			msg->rsp[1] = msg->data[1]; /* Addr */
4565 			msg->rsp[2] = msg->data[2] & 0xfc; /* rqSeq */
4566 			msg->rsp[2] |= msg->data[0] & 0x3; /* rsLUN */
4567 			msg->rsp[3] = msg->data[3]; /* Cmd */
4568 			msg->rsp[4] = IPMI_ERR_UNSPECIFIED;
4569 			msg->rsp_size = 5;
4570 		}
4571 	} else if ((msg->data_size >= 2)
4572 	    && (msg->data[0] == (IPMI_NETFN_APP_REQUEST << 2))
4573 	    && (msg->data[1] == IPMI_SEND_MSG_CMD)
4574 	    && (msg->user_data == NULL)) {
4575 
4576 		if (intf->in_shutdown)
4577 			goto out;
4578 
4579 		/*
4580 		 * This is the local response to a command send, start
4581 		 * the timer for these.  The user_data will not be
4582 		 * NULL if this is a response send, and we will let
4583 		 * response sends just go through.
4584 		 */
4585 
4586 		/*
4587 		 * Check for errors, if we get certain errors (ones
4588 		 * that mean basically we can try again later), we
4589 		 * ignore them and start the timer.  Otherwise we
4590 		 * report the error immediately.
4591 		 */
4592 		if ((msg->rsp_size >= 3) && (msg->rsp[2] != 0)
4593 		    && (msg->rsp[2] != IPMI_NODE_BUSY_ERR)
4594 		    && (msg->rsp[2] != IPMI_LOST_ARBITRATION_ERR)
4595 		    && (msg->rsp[2] != IPMI_BUS_ERR)
4596 		    && (msg->rsp[2] != IPMI_NAK_ON_WRITE_ERR)) {
4597 			int ch = msg->rsp[3] & 0xf;
4598 			struct ipmi_channel *chans;
4599 
4600 			/* Got an error sending the message, handle it. */
4601 
4602 			chans = READ_ONCE(intf->channel_list)->c;
4603 			if ((chans[ch].medium == IPMI_CHANNEL_MEDIUM_8023LAN)
4604 			    || (chans[ch].medium == IPMI_CHANNEL_MEDIUM_ASYNC))
4605 				ipmi_inc_stat(intf, sent_lan_command_errs);
4606 			else
4607 				ipmi_inc_stat(intf, sent_ipmb_command_errs);
4608 			intf_err_seq(intf, msg->msgid, msg->rsp[2]);
4609 		} else
4610 			/* The message was sent, start the timer. */
4611 			intf_start_seq_timer(intf, msg->msgid);
4612 		requeue = 0;
4613 		goto out;
4614 	} else if (((msg->rsp[0] >> 2) != ((msg->data[0] >> 2) | 1))
4615 		   || (msg->rsp[1] != msg->data[1])) {
4616 		/*
4617 		 * The NetFN and Command in the response is not even
4618 		 * marginally correct.
4619 		 */
4620 		dev_warn(intf->si_dev,
4621 			 "BMC returned incorrect response, expected netfn %x cmd %x, got netfn %x cmd %x\n",
4622 			 (msg->data[0] >> 2) | 1, msg->data[1],
4623 			 msg->rsp[0] >> 2, msg->rsp[1]);
4624 
4625 		goto return_unspecified;
4626 	}
4627 
4628 	if (msg->type == IPMI_SMI_MSG_TYPE_IPMB_DIRECT) {
4629 		if ((msg->data[0] >> 2) & 1) {
4630 			/* It's a response to a sent response. */
4631 			chan = 0;
4632 			cc = msg->rsp[4];
4633 			goto process_response_response;
4634 		}
4635 		if (is_cmd)
4636 			requeue = handle_ipmb_direct_rcv_cmd(intf, msg);
4637 		else
4638 			requeue = handle_ipmb_direct_rcv_rsp(intf, msg);
4639 	} else if ((msg->rsp[0] == ((IPMI_NETFN_APP_REQUEST|1) << 2))
4640 		   && (msg->rsp[1] == IPMI_SEND_MSG_CMD)
4641 		   && (msg->user_data != NULL)) {
4642 		/*
4643 		 * It's a response to a response we sent.  For this we
4644 		 * deliver a send message response to the user.
4645 		 */
4646 		struct ipmi_recv_msg *recv_msg;
4647 
4648 		chan = msg->data[2] & 0x0f;
4649 		if (chan >= IPMI_MAX_CHANNELS)
4650 			/* Invalid channel number */
4651 			goto out;
4652 		cc = msg->rsp[2];
4653 
4654 process_response_response:
4655 		recv_msg = msg->user_data;
4656 
4657 		requeue = 0;
4658 		if (!recv_msg)
4659 			goto out;
4660 
4661 		recv_msg->recv_type = IPMI_RESPONSE_RESPONSE_TYPE;
4662 		recv_msg->msg.data = recv_msg->msg_data;
4663 		recv_msg->msg_data[0] = cc;
4664 		recv_msg->msg.data_len = 1;
4665 		deliver_local_response(intf, recv_msg);
4666 	} else if ((msg->rsp[0] == ((IPMI_NETFN_APP_REQUEST|1) << 2))
4667 		   && (msg->rsp[1] == IPMI_GET_MSG_CMD)) {
4668 		struct ipmi_channel   *chans;
4669 
4670 		/* It's from the receive queue. */
4671 		chan = msg->rsp[3] & 0xf;
4672 		if (chan >= IPMI_MAX_CHANNELS) {
4673 			/* Invalid channel number */
4674 			requeue = 0;
4675 			goto out;
4676 		}
4677 
4678 		/*
4679 		 * We need to make sure the channels have been initialized.
4680 		 * The channel_handler routine will set the "curr_channel"
4681 		 * equal to or greater than IPMI_MAX_CHANNELS when all the
4682 		 * channels for this interface have been initialized.
4683 		 */
4684 		if (!intf->channels_ready) {
4685 			requeue = 0; /* Throw the message away */
4686 			goto out;
4687 		}
4688 
4689 		chans = READ_ONCE(intf->channel_list)->c;
4690 
4691 		switch (chans[chan].medium) {
4692 		case IPMI_CHANNEL_MEDIUM_IPMB:
4693 			if (msg->rsp[4] & 0x04) {
4694 				/*
4695 				 * It's a response, so find the
4696 				 * requesting message and send it up.
4697 				 */
4698 				requeue = handle_ipmb_get_msg_rsp(intf, msg);
4699 			} else {
4700 				/*
4701 				 * It's a command to the SMS from some other
4702 				 * entity.  Handle that.
4703 				 */
4704 				requeue = handle_ipmb_get_msg_cmd(intf, msg);
4705 			}
4706 			break;
4707 
4708 		case IPMI_CHANNEL_MEDIUM_8023LAN:
4709 		case IPMI_CHANNEL_MEDIUM_ASYNC:
4710 			if (msg->rsp[6] & 0x04) {
4711 				/*
4712 				 * It's a response, so find the
4713 				 * requesting message and send it up.
4714 				 */
4715 				requeue = handle_lan_get_msg_rsp(intf, msg);
4716 			} else {
4717 				/*
4718 				 * It's a command to the SMS from some other
4719 				 * entity.  Handle that.
4720 				 */
4721 				requeue = handle_lan_get_msg_cmd(intf, msg);
4722 			}
4723 			break;
4724 
4725 		default:
4726 			/* Check for OEM Channels.  Clients had better
4727 			   register for these commands. */
4728 			if ((chans[chan].medium >= IPMI_CHANNEL_MEDIUM_OEM_MIN)
4729 			    && (chans[chan].medium
4730 				<= IPMI_CHANNEL_MEDIUM_OEM_MAX)) {
4731 				requeue = handle_oem_get_msg_cmd(intf, msg);
4732 			} else {
4733 				/*
4734 				 * We don't handle the channel type, so just
4735 				 * free the message.
4736 				 */
4737 				requeue = 0;
4738 			}
4739 		}
4740 
4741 	} else if ((msg->rsp[0] == ((IPMI_NETFN_APP_REQUEST|1) << 2))
4742 		   && (msg->rsp[1] == IPMI_READ_EVENT_MSG_BUFFER_CMD)) {
4743 		/* It's an asynchronous event. */
4744 		requeue = handle_read_event_rsp(intf, msg);
4745 	} else {
4746 		/* It's a response from the local BMC. */
4747 		requeue = handle_bmc_rsp(intf, msg);
4748 	}
4749 
4750  out:
4751 	return requeue;
4752 }
4753 
4754 /*
4755  * If there are messages in the queue or pretimeouts, handle them.
4756  */
handle_new_recv_msgs(struct ipmi_smi * intf)4757 static void handle_new_recv_msgs(struct ipmi_smi *intf)
4758 {
4759 	struct ipmi_smi_msg  *smi_msg;
4760 	unsigned long        flags = 0;
4761 	int                  rv;
4762 	int                  run_to_completion = intf->run_to_completion;
4763 
4764 	/* See if any waiting messages need to be processed. */
4765 	if (!run_to_completion)
4766 		spin_lock_irqsave(&intf->waiting_rcv_msgs_lock, flags);
4767 	while (!list_empty(&intf->waiting_rcv_msgs)) {
4768 		smi_msg = list_entry(intf->waiting_rcv_msgs.next,
4769 				     struct ipmi_smi_msg, link);
4770 		list_del(&smi_msg->link);
4771 		if (!run_to_completion)
4772 			spin_unlock_irqrestore(&intf->waiting_rcv_msgs_lock,
4773 					       flags);
4774 		rv = handle_one_recv_msg(intf, smi_msg);
4775 		if (!run_to_completion)
4776 			spin_lock_irqsave(&intf->waiting_rcv_msgs_lock, flags);
4777 		if (rv > 0) {
4778 			/*
4779 			 * To preserve message order, quit if we
4780 			 * can't handle a message.  Add the message
4781 			 * back at the head, this is safe because this
4782 			 * tasklet is the only thing that pulls the
4783 			 * messages.
4784 			 */
4785 			list_add(&smi_msg->link, &intf->waiting_rcv_msgs);
4786 			break;
4787 		} else {
4788 			if (rv == 0)
4789 				/* Message handled */
4790 				ipmi_free_smi_msg(smi_msg);
4791 			/* If rv < 0, fatal error, del but don't free. */
4792 		}
4793 	}
4794 	if (!run_to_completion)
4795 		spin_unlock_irqrestore(&intf->waiting_rcv_msgs_lock, flags);
4796 
4797 	/*
4798 	 * If the pretimout count is non-zero, decrement one from it and
4799 	 * deliver pretimeouts to all the users.
4800 	 */
4801 	if (atomic_add_unless(&intf->watchdog_pretimeouts_to_deliver, -1, 0)) {
4802 		struct ipmi_user *user;
4803 		int index;
4804 
4805 		index = srcu_read_lock(&intf->users_srcu);
4806 		list_for_each_entry_rcu(user, &intf->users, link) {
4807 			if (user->handler->ipmi_watchdog_pretimeout)
4808 				user->handler->ipmi_watchdog_pretimeout(
4809 					user->handler_data);
4810 		}
4811 		srcu_read_unlock(&intf->users_srcu, index);
4812 	}
4813 }
4814 
smi_recv_tasklet(struct tasklet_struct * t)4815 static void smi_recv_tasklet(struct tasklet_struct *t)
4816 {
4817 	unsigned long flags = 0; /* keep us warning-free. */
4818 	struct ipmi_smi *intf = from_tasklet(intf, t, recv_tasklet);
4819 	int run_to_completion = intf->run_to_completion;
4820 	struct ipmi_smi_msg *newmsg = NULL;
4821 
4822 	/*
4823 	 * Start the next message if available.
4824 	 *
4825 	 * Do this here, not in the actual receiver, because we may deadlock
4826 	 * because the lower layer is allowed to hold locks while calling
4827 	 * message delivery.
4828 	 */
4829 
4830 	rcu_read_lock();
4831 
4832 	if (!run_to_completion)
4833 		spin_lock_irqsave(&intf->xmit_msgs_lock, flags);
4834 	if (intf->curr_msg == NULL && !intf->in_shutdown) {
4835 		struct list_head *entry = NULL;
4836 
4837 		/* Pick the high priority queue first. */
4838 		if (!list_empty(&intf->hp_xmit_msgs))
4839 			entry = intf->hp_xmit_msgs.next;
4840 		else if (!list_empty(&intf->xmit_msgs))
4841 			entry = intf->xmit_msgs.next;
4842 
4843 		if (entry) {
4844 			list_del(entry);
4845 			newmsg = list_entry(entry, struct ipmi_smi_msg, link);
4846 			intf->curr_msg = newmsg;
4847 		}
4848 	}
4849 
4850 	if (!run_to_completion)
4851 		spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags);
4852 	if (newmsg)
4853 		intf->handlers->sender(intf->send_info, newmsg);
4854 
4855 	rcu_read_unlock();
4856 
4857 	handle_new_recv_msgs(intf);
4858 }
4859 
4860 /* Handle a new message from the lower layer. */
ipmi_smi_msg_received(struct ipmi_smi * intf,struct ipmi_smi_msg * msg)4861 void ipmi_smi_msg_received(struct ipmi_smi *intf,
4862 			   struct ipmi_smi_msg *msg)
4863 {
4864 	unsigned long flags = 0; /* keep us warning-free. */
4865 	int run_to_completion = intf->run_to_completion;
4866 
4867 	/*
4868 	 * To preserve message order, we keep a queue and deliver from
4869 	 * a tasklet.
4870 	 */
4871 	if (!run_to_completion)
4872 		spin_lock_irqsave(&intf->waiting_rcv_msgs_lock, flags);
4873 	list_add_tail(&msg->link, &intf->waiting_rcv_msgs);
4874 	if (!run_to_completion)
4875 		spin_unlock_irqrestore(&intf->waiting_rcv_msgs_lock,
4876 				       flags);
4877 
4878 	if (!run_to_completion)
4879 		spin_lock_irqsave(&intf->xmit_msgs_lock, flags);
4880 	/*
4881 	 * We can get an asynchronous event or receive message in addition
4882 	 * to commands we send.
4883 	 */
4884 	if (msg == intf->curr_msg)
4885 		intf->curr_msg = NULL;
4886 	if (!run_to_completion)
4887 		spin_unlock_irqrestore(&intf->xmit_msgs_lock, flags);
4888 
4889 	if (run_to_completion)
4890 		smi_recv_tasklet(&intf->recv_tasklet);
4891 	else
4892 		tasklet_schedule(&intf->recv_tasklet);
4893 }
4894 EXPORT_SYMBOL(ipmi_smi_msg_received);
4895 
ipmi_smi_watchdog_pretimeout(struct ipmi_smi * intf)4896 void ipmi_smi_watchdog_pretimeout(struct ipmi_smi *intf)
4897 {
4898 	if (intf->in_shutdown)
4899 		return;
4900 
4901 	atomic_set(&intf->watchdog_pretimeouts_to_deliver, 1);
4902 	tasklet_schedule(&intf->recv_tasklet);
4903 }
4904 EXPORT_SYMBOL(ipmi_smi_watchdog_pretimeout);
4905 
4906 static struct ipmi_smi_msg *
smi_from_recv_msg(struct ipmi_smi * intf,struct ipmi_recv_msg * recv_msg,unsigned char seq,long seqid)4907 smi_from_recv_msg(struct ipmi_smi *intf, struct ipmi_recv_msg *recv_msg,
4908 		  unsigned char seq, long seqid)
4909 {
4910 	struct ipmi_smi_msg *smi_msg = ipmi_alloc_smi_msg();
4911 	if (!smi_msg)
4912 		/*
4913 		 * If we can't allocate the message, then just return, we
4914 		 * get 4 retries, so this should be ok.
4915 		 */
4916 		return NULL;
4917 
4918 	memcpy(smi_msg->data, recv_msg->msg.data, recv_msg->msg.data_len);
4919 	smi_msg->data_size = recv_msg->msg.data_len;
4920 	smi_msg->msgid = STORE_SEQ_IN_MSGID(seq, seqid);
4921 
4922 	dev_dbg(intf->si_dev, "Resend: %*ph\n",
4923 		smi_msg->data_size, smi_msg->data);
4924 
4925 	return smi_msg;
4926 }
4927 
check_msg_timeout(struct ipmi_smi * intf,struct seq_table * ent,struct list_head * timeouts,unsigned long timeout_period,int slot,unsigned long * flags,bool * need_timer)4928 static void check_msg_timeout(struct ipmi_smi *intf, struct seq_table *ent,
4929 			      struct list_head *timeouts,
4930 			      unsigned long timeout_period,
4931 			      int slot, unsigned long *flags,
4932 			      bool *need_timer)
4933 {
4934 	struct ipmi_recv_msg *msg;
4935 
4936 	if (intf->in_shutdown)
4937 		return;
4938 
4939 	if (!ent->inuse)
4940 		return;
4941 
4942 	if (timeout_period < ent->timeout) {
4943 		ent->timeout -= timeout_period;
4944 		*need_timer = true;
4945 		return;
4946 	}
4947 
4948 	if (ent->retries_left == 0) {
4949 		/* The message has used all its retries. */
4950 		ent->inuse = 0;
4951 		smi_remove_watch(intf, IPMI_WATCH_MASK_CHECK_MESSAGES);
4952 		msg = ent->recv_msg;
4953 		list_add_tail(&msg->link, timeouts);
4954 		if (ent->broadcast)
4955 			ipmi_inc_stat(intf, timed_out_ipmb_broadcasts);
4956 		else if (is_lan_addr(&ent->recv_msg->addr))
4957 			ipmi_inc_stat(intf, timed_out_lan_commands);
4958 		else
4959 			ipmi_inc_stat(intf, timed_out_ipmb_commands);
4960 	} else {
4961 		struct ipmi_smi_msg *smi_msg;
4962 		/* More retries, send again. */
4963 
4964 		*need_timer = true;
4965 
4966 		/*
4967 		 * Start with the max timer, set to normal timer after
4968 		 * the message is sent.
4969 		 */
4970 		ent->timeout = MAX_MSG_TIMEOUT;
4971 		ent->retries_left--;
4972 		smi_msg = smi_from_recv_msg(intf, ent->recv_msg, slot,
4973 					    ent->seqid);
4974 		if (!smi_msg) {
4975 			if (is_lan_addr(&ent->recv_msg->addr))
4976 				ipmi_inc_stat(intf,
4977 					      dropped_rexmit_lan_commands);
4978 			else
4979 				ipmi_inc_stat(intf,
4980 					      dropped_rexmit_ipmb_commands);
4981 			return;
4982 		}
4983 
4984 		spin_unlock_irqrestore(&intf->seq_lock, *flags);
4985 
4986 		/*
4987 		 * Send the new message.  We send with a zero
4988 		 * priority.  It timed out, I doubt time is that
4989 		 * critical now, and high priority messages are really
4990 		 * only for messages to the local MC, which don't get
4991 		 * resent.
4992 		 */
4993 		if (intf->handlers) {
4994 			if (is_lan_addr(&ent->recv_msg->addr))
4995 				ipmi_inc_stat(intf,
4996 					      retransmitted_lan_commands);
4997 			else
4998 				ipmi_inc_stat(intf,
4999 					      retransmitted_ipmb_commands);
5000 
5001 			smi_send(intf, intf->handlers, smi_msg, 0);
5002 		} else
5003 			ipmi_free_smi_msg(smi_msg);
5004 
5005 		spin_lock_irqsave(&intf->seq_lock, *flags);
5006 	}
5007 }
5008 
ipmi_timeout_handler(struct ipmi_smi * intf,unsigned long timeout_period)5009 static bool ipmi_timeout_handler(struct ipmi_smi *intf,
5010 				 unsigned long timeout_period)
5011 {
5012 	struct list_head     timeouts;
5013 	struct ipmi_recv_msg *msg, *msg2;
5014 	unsigned long        flags;
5015 	int                  i;
5016 	bool                 need_timer = false;
5017 
5018 	if (!intf->bmc_registered) {
5019 		kref_get(&intf->refcount);
5020 		if (!schedule_work(&intf->bmc_reg_work)) {
5021 			kref_put(&intf->refcount, intf_free);
5022 			need_timer = true;
5023 		}
5024 	}
5025 
5026 	/*
5027 	 * Go through the seq table and find any messages that
5028 	 * have timed out, putting them in the timeouts
5029 	 * list.
5030 	 */
5031 	INIT_LIST_HEAD(&timeouts);
5032 	spin_lock_irqsave(&intf->seq_lock, flags);
5033 	if (intf->ipmb_maintenance_mode_timeout) {
5034 		if (intf->ipmb_maintenance_mode_timeout <= timeout_period)
5035 			intf->ipmb_maintenance_mode_timeout = 0;
5036 		else
5037 			intf->ipmb_maintenance_mode_timeout -= timeout_period;
5038 	}
5039 	for (i = 0; i < IPMI_IPMB_NUM_SEQ; i++)
5040 		check_msg_timeout(intf, &intf->seq_table[i],
5041 				  &timeouts, timeout_period, i,
5042 				  &flags, &need_timer);
5043 	spin_unlock_irqrestore(&intf->seq_lock, flags);
5044 
5045 	list_for_each_entry_safe(msg, msg2, &timeouts, link)
5046 		deliver_err_response(intf, msg, IPMI_TIMEOUT_COMPLETION_CODE);
5047 
5048 	/*
5049 	 * Maintenance mode handling.  Check the timeout
5050 	 * optimistically before we claim the lock.  It may
5051 	 * mean a timeout gets missed occasionally, but that
5052 	 * only means the timeout gets extended by one period
5053 	 * in that case.  No big deal, and it avoids the lock
5054 	 * most of the time.
5055 	 */
5056 	if (intf->auto_maintenance_timeout > 0) {
5057 		spin_lock_irqsave(&intf->maintenance_mode_lock, flags);
5058 		if (intf->auto_maintenance_timeout > 0) {
5059 			intf->auto_maintenance_timeout
5060 				-= timeout_period;
5061 			if (!intf->maintenance_mode
5062 			    && (intf->auto_maintenance_timeout <= 0)) {
5063 				intf->maintenance_mode_enable = false;
5064 				maintenance_mode_update(intf);
5065 			}
5066 		}
5067 		spin_unlock_irqrestore(&intf->maintenance_mode_lock,
5068 				       flags);
5069 	}
5070 
5071 	tasklet_schedule(&intf->recv_tasklet);
5072 
5073 	return need_timer;
5074 }
5075 
ipmi_request_event(struct ipmi_smi * intf)5076 static void ipmi_request_event(struct ipmi_smi *intf)
5077 {
5078 	/* No event requests when in maintenance mode. */
5079 	if (intf->maintenance_mode_enable)
5080 		return;
5081 
5082 	if (!intf->in_shutdown)
5083 		intf->handlers->request_events(intf->send_info);
5084 }
5085 
5086 static struct timer_list ipmi_timer;
5087 
5088 static atomic_t stop_operation;
5089 
ipmi_timeout(struct timer_list * unused)5090 static void ipmi_timeout(struct timer_list *unused)
5091 {
5092 	struct ipmi_smi *intf;
5093 	bool need_timer = false;
5094 	int index;
5095 
5096 	if (atomic_read(&stop_operation))
5097 		return;
5098 
5099 	index = srcu_read_lock(&ipmi_interfaces_srcu);
5100 	list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
5101 		if (atomic_read(&intf->event_waiters)) {
5102 			intf->ticks_to_req_ev--;
5103 			if (intf->ticks_to_req_ev == 0) {
5104 				ipmi_request_event(intf);
5105 				intf->ticks_to_req_ev = IPMI_REQUEST_EV_TIME;
5106 			}
5107 			need_timer = true;
5108 		}
5109 
5110 		need_timer |= ipmi_timeout_handler(intf, IPMI_TIMEOUT_TIME);
5111 	}
5112 	srcu_read_unlock(&ipmi_interfaces_srcu, index);
5113 
5114 	if (need_timer)
5115 		mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
5116 }
5117 
need_waiter(struct ipmi_smi * intf)5118 static void need_waiter(struct ipmi_smi *intf)
5119 {
5120 	/* Racy, but worst case we start the timer twice. */
5121 	if (!timer_pending(&ipmi_timer))
5122 		mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
5123 }
5124 
5125 static atomic_t smi_msg_inuse_count = ATOMIC_INIT(0);
5126 static atomic_t recv_msg_inuse_count = ATOMIC_INIT(0);
5127 
free_smi_msg(struct ipmi_smi_msg * msg)5128 static void free_smi_msg(struct ipmi_smi_msg *msg)
5129 {
5130 	atomic_dec(&smi_msg_inuse_count);
5131 	/* Try to keep as much stuff out of the panic path as possible. */
5132 	if (!oops_in_progress)
5133 		kfree(msg);
5134 }
5135 
ipmi_alloc_smi_msg(void)5136 struct ipmi_smi_msg *ipmi_alloc_smi_msg(void)
5137 {
5138 	struct ipmi_smi_msg *rv;
5139 	rv = kmalloc(sizeof(struct ipmi_smi_msg), GFP_ATOMIC);
5140 	if (rv) {
5141 		rv->done = free_smi_msg;
5142 		rv->user_data = NULL;
5143 		rv->type = IPMI_SMI_MSG_TYPE_NORMAL;
5144 		atomic_inc(&smi_msg_inuse_count);
5145 	}
5146 	return rv;
5147 }
5148 EXPORT_SYMBOL(ipmi_alloc_smi_msg);
5149 
free_recv_msg(struct ipmi_recv_msg * msg)5150 static void free_recv_msg(struct ipmi_recv_msg *msg)
5151 {
5152 	atomic_dec(&recv_msg_inuse_count);
5153 	/* Try to keep as much stuff out of the panic path as possible. */
5154 	if (!oops_in_progress)
5155 		kfree(msg);
5156 }
5157 
ipmi_alloc_recv_msg(void)5158 static struct ipmi_recv_msg *ipmi_alloc_recv_msg(void)
5159 {
5160 	struct ipmi_recv_msg *rv;
5161 
5162 	rv = kmalloc(sizeof(struct ipmi_recv_msg), GFP_ATOMIC);
5163 	if (rv) {
5164 		rv->user = NULL;
5165 		rv->done = free_recv_msg;
5166 		atomic_inc(&recv_msg_inuse_count);
5167 	}
5168 	return rv;
5169 }
5170 
ipmi_free_recv_msg(struct ipmi_recv_msg * msg)5171 void ipmi_free_recv_msg(struct ipmi_recv_msg *msg)
5172 {
5173 	if (msg->user && !oops_in_progress)
5174 		kref_put(&msg->user->refcount, free_user);
5175 	msg->done(msg);
5176 }
5177 EXPORT_SYMBOL(ipmi_free_recv_msg);
5178 
5179 static atomic_t panic_done_count = ATOMIC_INIT(0);
5180 
dummy_smi_done_handler(struct ipmi_smi_msg * msg)5181 static void dummy_smi_done_handler(struct ipmi_smi_msg *msg)
5182 {
5183 	atomic_dec(&panic_done_count);
5184 }
5185 
dummy_recv_done_handler(struct ipmi_recv_msg * msg)5186 static void dummy_recv_done_handler(struct ipmi_recv_msg *msg)
5187 {
5188 	atomic_dec(&panic_done_count);
5189 }
5190 
5191 /*
5192  * Inside a panic, send a message and wait for a response.
5193  */
ipmi_panic_request_and_wait(struct ipmi_smi * intf,struct ipmi_addr * addr,struct kernel_ipmi_msg * msg)5194 static void ipmi_panic_request_and_wait(struct ipmi_smi *intf,
5195 					struct ipmi_addr *addr,
5196 					struct kernel_ipmi_msg *msg)
5197 {
5198 	struct ipmi_smi_msg  smi_msg;
5199 	struct ipmi_recv_msg recv_msg;
5200 	int rv;
5201 
5202 	smi_msg.done = dummy_smi_done_handler;
5203 	recv_msg.done = dummy_recv_done_handler;
5204 	atomic_add(2, &panic_done_count);
5205 	rv = i_ipmi_request(NULL,
5206 			    intf,
5207 			    addr,
5208 			    0,
5209 			    msg,
5210 			    intf,
5211 			    &smi_msg,
5212 			    &recv_msg,
5213 			    0,
5214 			    intf->addrinfo[0].address,
5215 			    intf->addrinfo[0].lun,
5216 			    0, 1); /* Don't retry, and don't wait. */
5217 	if (rv)
5218 		atomic_sub(2, &panic_done_count);
5219 	else if (intf->handlers->flush_messages)
5220 		intf->handlers->flush_messages(intf->send_info);
5221 
5222 	while (atomic_read(&panic_done_count) != 0)
5223 		ipmi_poll(intf);
5224 }
5225 
event_receiver_fetcher(struct ipmi_smi * intf,struct ipmi_recv_msg * msg)5226 static void event_receiver_fetcher(struct ipmi_smi *intf,
5227 				   struct ipmi_recv_msg *msg)
5228 {
5229 	if ((msg->addr.addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
5230 	    && (msg->msg.netfn == IPMI_NETFN_SENSOR_EVENT_RESPONSE)
5231 	    && (msg->msg.cmd == IPMI_GET_EVENT_RECEIVER_CMD)
5232 	    && (msg->msg.data[0] == IPMI_CC_NO_ERROR)) {
5233 		/* A get event receiver command, save it. */
5234 		intf->event_receiver = msg->msg.data[1];
5235 		intf->event_receiver_lun = msg->msg.data[2] & 0x3;
5236 	}
5237 }
5238 
device_id_fetcher(struct ipmi_smi * intf,struct ipmi_recv_msg * msg)5239 static void device_id_fetcher(struct ipmi_smi *intf, struct ipmi_recv_msg *msg)
5240 {
5241 	if ((msg->addr.addr_type == IPMI_SYSTEM_INTERFACE_ADDR_TYPE)
5242 	    && (msg->msg.netfn == IPMI_NETFN_APP_RESPONSE)
5243 	    && (msg->msg.cmd == IPMI_GET_DEVICE_ID_CMD)
5244 	    && (msg->msg.data[0] == IPMI_CC_NO_ERROR)) {
5245 		/*
5246 		 * A get device id command, save if we are an event
5247 		 * receiver or generator.
5248 		 */
5249 		intf->local_sel_device = (msg->msg.data[6] >> 2) & 1;
5250 		intf->local_event_generator = (msg->msg.data[6] >> 5) & 1;
5251 	}
5252 }
5253 
send_panic_events(struct ipmi_smi * intf,char * str)5254 static void send_panic_events(struct ipmi_smi *intf, char *str)
5255 {
5256 	struct kernel_ipmi_msg msg;
5257 	unsigned char data[16];
5258 	struct ipmi_system_interface_addr *si;
5259 	struct ipmi_addr addr;
5260 	char *p = str;
5261 	struct ipmi_ipmb_addr *ipmb;
5262 	int j;
5263 
5264 	if (ipmi_send_panic_event == IPMI_SEND_PANIC_EVENT_NONE)
5265 		return;
5266 
5267 	si = (struct ipmi_system_interface_addr *) &addr;
5268 	si->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
5269 	si->channel = IPMI_BMC_CHANNEL;
5270 	si->lun = 0;
5271 
5272 	/* Fill in an event telling that we have failed. */
5273 	msg.netfn = 0x04; /* Sensor or Event. */
5274 	msg.cmd = 2; /* Platform event command. */
5275 	msg.data = data;
5276 	msg.data_len = 8;
5277 	data[0] = 0x41; /* Kernel generator ID, IPMI table 5-4 */
5278 	data[1] = 0x03; /* This is for IPMI 1.0. */
5279 	data[2] = 0x20; /* OS Critical Stop, IPMI table 36-3 */
5280 	data[4] = 0x6f; /* Sensor specific, IPMI table 36-1 */
5281 	data[5] = 0xa1; /* Runtime stop OEM bytes 2 & 3. */
5282 
5283 	/*
5284 	 * Put a few breadcrumbs in.  Hopefully later we can add more things
5285 	 * to make the panic events more useful.
5286 	 */
5287 	if (str) {
5288 		data[3] = str[0];
5289 		data[6] = str[1];
5290 		data[7] = str[2];
5291 	}
5292 
5293 	/* Send the event announcing the panic. */
5294 	ipmi_panic_request_and_wait(intf, &addr, &msg);
5295 
5296 	/*
5297 	 * On every interface, dump a bunch of OEM event holding the
5298 	 * string.
5299 	 */
5300 	if (ipmi_send_panic_event != IPMI_SEND_PANIC_EVENT_STRING || !str)
5301 		return;
5302 
5303 	/*
5304 	 * intf_num is used as an marker to tell if the
5305 	 * interface is valid.  Thus we need a read barrier to
5306 	 * make sure data fetched before checking intf_num
5307 	 * won't be used.
5308 	 */
5309 	smp_rmb();
5310 
5311 	/*
5312 	 * First job here is to figure out where to send the
5313 	 * OEM events.  There's no way in IPMI to send OEM
5314 	 * events using an event send command, so we have to
5315 	 * find the SEL to put them in and stick them in
5316 	 * there.
5317 	 */
5318 
5319 	/* Get capabilities from the get device id. */
5320 	intf->local_sel_device = 0;
5321 	intf->local_event_generator = 0;
5322 	intf->event_receiver = 0;
5323 
5324 	/* Request the device info from the local MC. */
5325 	msg.netfn = IPMI_NETFN_APP_REQUEST;
5326 	msg.cmd = IPMI_GET_DEVICE_ID_CMD;
5327 	msg.data = NULL;
5328 	msg.data_len = 0;
5329 	intf->null_user_handler = device_id_fetcher;
5330 	ipmi_panic_request_and_wait(intf, &addr, &msg);
5331 
5332 	if (intf->local_event_generator) {
5333 		/* Request the event receiver from the local MC. */
5334 		msg.netfn = IPMI_NETFN_SENSOR_EVENT_REQUEST;
5335 		msg.cmd = IPMI_GET_EVENT_RECEIVER_CMD;
5336 		msg.data = NULL;
5337 		msg.data_len = 0;
5338 		intf->null_user_handler = event_receiver_fetcher;
5339 		ipmi_panic_request_and_wait(intf, &addr, &msg);
5340 	}
5341 	intf->null_user_handler = NULL;
5342 
5343 	/*
5344 	 * Validate the event receiver.  The low bit must not
5345 	 * be 1 (it must be a valid IPMB address), it cannot
5346 	 * be zero, and it must not be my address.
5347 	 */
5348 	if (((intf->event_receiver & 1) == 0)
5349 	    && (intf->event_receiver != 0)
5350 	    && (intf->event_receiver != intf->addrinfo[0].address)) {
5351 		/*
5352 		 * The event receiver is valid, send an IPMB
5353 		 * message.
5354 		 */
5355 		ipmb = (struct ipmi_ipmb_addr *) &addr;
5356 		ipmb->addr_type = IPMI_IPMB_ADDR_TYPE;
5357 		ipmb->channel = 0; /* FIXME - is this right? */
5358 		ipmb->lun = intf->event_receiver_lun;
5359 		ipmb->slave_addr = intf->event_receiver;
5360 	} else if (intf->local_sel_device) {
5361 		/*
5362 		 * The event receiver was not valid (or was
5363 		 * me), but I am an SEL device, just dump it
5364 		 * in my SEL.
5365 		 */
5366 		si = (struct ipmi_system_interface_addr *) &addr;
5367 		si->addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
5368 		si->channel = IPMI_BMC_CHANNEL;
5369 		si->lun = 0;
5370 	} else
5371 		return; /* No where to send the event. */
5372 
5373 	msg.netfn = IPMI_NETFN_STORAGE_REQUEST; /* Storage. */
5374 	msg.cmd = IPMI_ADD_SEL_ENTRY_CMD;
5375 	msg.data = data;
5376 	msg.data_len = 16;
5377 
5378 	j = 0;
5379 	while (*p) {
5380 		int size = strlen(p);
5381 
5382 		if (size > 11)
5383 			size = 11;
5384 		data[0] = 0;
5385 		data[1] = 0;
5386 		data[2] = 0xf0; /* OEM event without timestamp. */
5387 		data[3] = intf->addrinfo[0].address;
5388 		data[4] = j++; /* sequence # */
5389 		/*
5390 		 * Always give 11 bytes, so strncpy will fill
5391 		 * it with zeroes for me.
5392 		 */
5393 		strncpy(data+5, p, 11);
5394 		p += size;
5395 
5396 		ipmi_panic_request_and_wait(intf, &addr, &msg);
5397 	}
5398 }
5399 
5400 static int has_panicked;
5401 
panic_event(struct notifier_block * this,unsigned long event,void * ptr)5402 static int panic_event(struct notifier_block *this,
5403 		       unsigned long         event,
5404 		       void                  *ptr)
5405 {
5406 	struct ipmi_smi *intf;
5407 	struct ipmi_user *user;
5408 
5409 	if (has_panicked)
5410 		return NOTIFY_DONE;
5411 	has_panicked = 1;
5412 
5413 	/* For every registered interface, set it to run to completion. */
5414 	list_for_each_entry_rcu(intf, &ipmi_interfaces, link) {
5415 		if (!intf->handlers || intf->intf_num == -1)
5416 			/* Interface is not ready. */
5417 			continue;
5418 
5419 		if (!intf->handlers->poll)
5420 			continue;
5421 
5422 		/*
5423 		 * If we were interrupted while locking xmit_msgs_lock or
5424 		 * waiting_rcv_msgs_lock, the corresponding list may be
5425 		 * corrupted.  In this case, drop items on the list for
5426 		 * the safety.
5427 		 */
5428 		if (!spin_trylock(&intf->xmit_msgs_lock)) {
5429 			INIT_LIST_HEAD(&intf->xmit_msgs);
5430 			INIT_LIST_HEAD(&intf->hp_xmit_msgs);
5431 		} else
5432 			spin_unlock(&intf->xmit_msgs_lock);
5433 
5434 		if (!spin_trylock(&intf->waiting_rcv_msgs_lock))
5435 			INIT_LIST_HEAD(&intf->waiting_rcv_msgs);
5436 		else
5437 			spin_unlock(&intf->waiting_rcv_msgs_lock);
5438 
5439 		intf->run_to_completion = 1;
5440 		if (intf->handlers->set_run_to_completion)
5441 			intf->handlers->set_run_to_completion(intf->send_info,
5442 							      1);
5443 
5444 		list_for_each_entry_rcu(user, &intf->users, link) {
5445 			if (user->handler->ipmi_panic_handler)
5446 				user->handler->ipmi_panic_handler(
5447 					user->handler_data);
5448 		}
5449 
5450 		send_panic_events(intf, ptr);
5451 	}
5452 
5453 	return NOTIFY_DONE;
5454 }
5455 
5456 /* Must be called with ipmi_interfaces_mutex held. */
ipmi_register_driver(void)5457 static int ipmi_register_driver(void)
5458 {
5459 	int rv;
5460 
5461 	if (drvregistered)
5462 		return 0;
5463 
5464 	rv = driver_register(&ipmidriver.driver);
5465 	if (rv)
5466 		pr_err("Could not register IPMI driver\n");
5467 	else
5468 		drvregistered = true;
5469 	return rv;
5470 }
5471 
5472 static struct notifier_block panic_block = {
5473 	.notifier_call	= panic_event,
5474 	.next		= NULL,
5475 	.priority	= 200	/* priority: INT_MAX >= x >= 0 */
5476 };
5477 
ipmi_init_msghandler(void)5478 static int ipmi_init_msghandler(void)
5479 {
5480 	int rv;
5481 
5482 	mutex_lock(&ipmi_interfaces_mutex);
5483 	rv = ipmi_register_driver();
5484 	if (rv)
5485 		goto out;
5486 	if (initialized)
5487 		goto out;
5488 
5489 	rv = init_srcu_struct(&ipmi_interfaces_srcu);
5490 	if (rv)
5491 		goto out;
5492 
5493 	remove_work_wq = create_singlethread_workqueue("ipmi-msghandler-remove-wq");
5494 	if (!remove_work_wq) {
5495 		pr_err("unable to create ipmi-msghandler-remove-wq workqueue");
5496 		rv = -ENOMEM;
5497 		goto out_wq;
5498 	}
5499 
5500 	timer_setup(&ipmi_timer, ipmi_timeout, 0);
5501 	mod_timer(&ipmi_timer, jiffies + IPMI_TIMEOUT_JIFFIES);
5502 
5503 	atomic_notifier_chain_register(&panic_notifier_list, &panic_block);
5504 
5505 	initialized = true;
5506 
5507 out_wq:
5508 	if (rv)
5509 		cleanup_srcu_struct(&ipmi_interfaces_srcu);
5510 out:
5511 	mutex_unlock(&ipmi_interfaces_mutex);
5512 	return rv;
5513 }
5514 
ipmi_init_msghandler_mod(void)5515 static int __init ipmi_init_msghandler_mod(void)
5516 {
5517 	int rv;
5518 
5519 	pr_info("version " IPMI_DRIVER_VERSION "\n");
5520 
5521 	mutex_lock(&ipmi_interfaces_mutex);
5522 	rv = ipmi_register_driver();
5523 	mutex_unlock(&ipmi_interfaces_mutex);
5524 
5525 	return rv;
5526 }
5527 
cleanup_ipmi(void)5528 static void __exit cleanup_ipmi(void)
5529 {
5530 	int count;
5531 
5532 	if (initialized) {
5533 		destroy_workqueue(remove_work_wq);
5534 
5535 		atomic_notifier_chain_unregister(&panic_notifier_list,
5536 						 &panic_block);
5537 
5538 		/*
5539 		 * This can't be called if any interfaces exist, so no worry
5540 		 * about shutting down the interfaces.
5541 		 */
5542 
5543 		/*
5544 		 * Tell the timer to stop, then wait for it to stop.  This
5545 		 * avoids problems with race conditions removing the timer
5546 		 * here.
5547 		 */
5548 		atomic_set(&stop_operation, 1);
5549 		del_timer_sync(&ipmi_timer);
5550 
5551 		initialized = false;
5552 
5553 		/* Check for buffer leaks. */
5554 		count = atomic_read(&smi_msg_inuse_count);
5555 		if (count != 0)
5556 			pr_warn("SMI message count %d at exit\n", count);
5557 		count = atomic_read(&recv_msg_inuse_count);
5558 		if (count != 0)
5559 			pr_warn("recv message count %d at exit\n", count);
5560 
5561 		cleanup_srcu_struct(&ipmi_interfaces_srcu);
5562 	}
5563 	if (drvregistered)
5564 		driver_unregister(&ipmidriver.driver);
5565 }
5566 module_exit(cleanup_ipmi);
5567 
5568 module_init(ipmi_init_msghandler_mod);
5569 MODULE_LICENSE("GPL");
5570 MODULE_AUTHOR("Corey Minyard <minyard@mvista.com>");
5571 MODULE_DESCRIPTION("Incoming and outgoing message routing for an IPMI interface.");
5572 MODULE_VERSION(IPMI_DRIVER_VERSION);
5573 MODULE_SOFTDEP("post: ipmi_devintf");
5574