1 /*
2 * Changes:
3 * Arnaldo Carvalho de Melo <acme@conectiva.com.br> 08/23/2000
4 * - get rid of some verify_areas and use __copy*user and __get/put_user
5 * for the ones that remain
6 */
7 #include <linux/module.h>
8 #include <linux/blkdev.h>
9 #include <linux/interrupt.h>
10 #include <linux/errno.h>
11 #include <linux/kernel.h>
12 #include <linux/sched.h>
13 #include <linux/mm.h>
14 #include <linux/string.h>
15 #include <asm/uaccess.h>
16
17 #include <scsi/scsi.h>
18 #include <scsi/scsi_cmnd.h>
19 #include <scsi/scsi_device.h>
20 #include <scsi/scsi_eh.h>
21 #include <scsi/scsi_host.h>
22 #include <scsi/scsi_ioctl.h>
23 #include <scsi/sg.h>
24 #include <scsi/scsi_dbg.h>
25
26 #include "scsi_logging.h"
27
28 #define NORMAL_RETRIES 5
29 #define IOCTL_NORMAL_TIMEOUT (10 * HZ)
30
31 #define MAX_BUF PAGE_SIZE
32
33 /**
34 * ioctl_probe -- return host identification
35 * @host: host to identify
36 * @buffer: userspace buffer for identification
37 *
38 * Return an identifying string at @buffer, if @buffer is non-NULL, filling
39 * to the length stored at * (int *) @buffer.
40 */
ioctl_probe(struct Scsi_Host * host,void __user * buffer)41 static int ioctl_probe(struct Scsi_Host *host, void __user *buffer)
42 {
43 unsigned int len, slen;
44 const char *string;
45
46 if (buffer) {
47 if (get_user(len, (unsigned int __user *) buffer))
48 return -EFAULT;
49
50 if (host->hostt->info)
51 string = host->hostt->info(host);
52 else
53 string = host->hostt->name;
54 if (string) {
55 slen = strlen(string);
56 if (len > slen)
57 len = slen + 1;
58 if (copy_to_user(buffer, string, len))
59 return -EFAULT;
60 }
61 }
62 return 1;
63 }
64
65 /*
66
67 * The SCSI_IOCTL_SEND_COMMAND ioctl sends a command out to the SCSI host.
68 * The IOCTL_NORMAL_TIMEOUT and NORMAL_RETRIES variables are used.
69 *
70 * dev is the SCSI device struct ptr, *(int *) arg is the length of the
71 * input data, if any, not including the command string & counts,
72 * *((int *)arg + 1) is the output buffer size in bytes.
73 *
74 * *(char *) ((int *) arg)[2] the actual command byte.
75 *
76 * Note that if more than MAX_BUF bytes are requested to be transferred,
77 * the ioctl will fail with error EINVAL.
78 *
79 * This size *does not* include the initial lengths that were passed.
80 *
81 * The SCSI command is read from the memory location immediately after the
82 * length words, and the input data is right after the command. The SCSI
83 * routines know the command size based on the opcode decode.
84 *
85 * The output area is then filled in starting from the command byte.
86 */
87
ioctl_internal_command(struct scsi_device * sdev,char * cmd,int timeout,int retries)88 static int ioctl_internal_command(struct scsi_device *sdev, char *cmd,
89 int timeout, int retries)
90 {
91 int result;
92 struct scsi_sense_hdr sshdr;
93
94 SCSI_LOG_IOCTL(1, printk("Trying ioctl with scsi command %d\n", *cmd));
95
96 result = scsi_execute_req(sdev, cmd, DMA_NONE, NULL, 0,
97 &sshdr, timeout, retries, NULL);
98
99 SCSI_LOG_IOCTL(2, printk("Ioctl returned 0x%x\n", result));
100
101 if ((driver_byte(result) & DRIVER_SENSE) &&
102 (scsi_sense_valid(&sshdr))) {
103 switch (sshdr.sense_key) {
104 case ILLEGAL_REQUEST:
105 if (cmd[0] == ALLOW_MEDIUM_REMOVAL)
106 sdev->lockable = 0;
107 else
108 printk(KERN_INFO "ioctl_internal_command: "
109 "ILLEGAL REQUEST asc=0x%x ascq=0x%x\n",
110 sshdr.asc, sshdr.ascq);
111 break;
112 case NOT_READY: /* This happens if there is no disc in drive */
113 if (sdev->removable)
114 break;
115 case UNIT_ATTENTION:
116 if (sdev->removable) {
117 sdev->changed = 1;
118 result = 0; /* This is no longer considered an error */
119 break;
120 }
121 default: /* Fall through for non-removable media */
122 sdev_printk(KERN_INFO, sdev,
123 "ioctl_internal_command return code = %x\n",
124 result);
125 scsi_print_sense_hdr(" ", &sshdr);
126 break;
127 }
128 }
129
130 SCSI_LOG_IOCTL(2, printk("IOCTL Releasing command\n"));
131 return result;
132 }
133
scsi_set_medium_removal(struct scsi_device * sdev,char state)134 int scsi_set_medium_removal(struct scsi_device *sdev, char state)
135 {
136 char scsi_cmd[MAX_COMMAND_SIZE];
137 int ret;
138
139 if (!sdev->removable || !sdev->lockable)
140 return 0;
141
142 scsi_cmd[0] = ALLOW_MEDIUM_REMOVAL;
143 scsi_cmd[1] = 0;
144 scsi_cmd[2] = 0;
145 scsi_cmd[3] = 0;
146 scsi_cmd[4] = state;
147 scsi_cmd[5] = 0;
148
149 ret = ioctl_internal_command(sdev, scsi_cmd,
150 IOCTL_NORMAL_TIMEOUT, NORMAL_RETRIES);
151 if (ret == 0)
152 sdev->locked = (state == SCSI_REMOVAL_PREVENT);
153 return ret;
154 }
155 EXPORT_SYMBOL(scsi_set_medium_removal);
156
157 /*
158 * The scsi_ioctl_get_pci() function places into arg the value
159 * pci_dev::slot_name (8 characters) for the PCI device (if any).
160 * Returns: 0 on success
161 * -ENXIO if there isn't a PCI device pointer
162 * (could be because the SCSI driver hasn't been
163 * updated yet, or because it isn't a SCSI
164 * device)
165 * any copy_to_user() error on failure there
166 */
scsi_ioctl_get_pci(struct scsi_device * sdev,void __user * arg)167 static int scsi_ioctl_get_pci(struct scsi_device *sdev, void __user *arg)
168 {
169 struct device *dev = scsi_get_device(sdev->host);
170 const char *name;
171
172 if (!dev)
173 return -ENXIO;
174
175 name = dev_name(dev);
176
177 /* compatibility with old ioctl which only returned
178 * 20 characters */
179 return copy_to_user(arg, name, min(strlen(name), (size_t)20))
180 ? -EFAULT: 0;
181 }
182
183
184 /**
185 * scsi_ioctl - Dispatch ioctl to scsi device
186 * @sdev: scsi device receiving ioctl
187 * @cmd: which ioctl is it
188 * @arg: data associated with ioctl
189 *
190 * Description: The scsi_ioctl() function differs from most ioctls in that it
191 * does not take a major/minor number as the dev field. Rather, it takes
192 * a pointer to a &struct scsi_device.
193 */
scsi_ioctl(struct scsi_device * sdev,int cmd,void __user * arg)194 int scsi_ioctl(struct scsi_device *sdev, int cmd, void __user *arg)
195 {
196 char scsi_cmd[MAX_COMMAND_SIZE];
197
198 /* No idea how this happens.... */
199 if (!sdev)
200 return -ENXIO;
201
202 /*
203 * If we are in the middle of error recovery, don't let anyone
204 * else try and use this device. Also, if error recovery fails, it
205 * may try and take the device offline, in which case all further
206 * access to the device is prohibited.
207 */
208 if (!scsi_block_when_processing_errors(sdev))
209 return -ENODEV;
210
211 /* Check for deprecated ioctls ... all the ioctls which don't
212 * follow the new unique numbering scheme are deprecated */
213 switch (cmd) {
214 case SCSI_IOCTL_SEND_COMMAND:
215 case SCSI_IOCTL_TEST_UNIT_READY:
216 case SCSI_IOCTL_BENCHMARK_COMMAND:
217 case SCSI_IOCTL_SYNC:
218 case SCSI_IOCTL_START_UNIT:
219 case SCSI_IOCTL_STOP_UNIT:
220 printk(KERN_WARNING "program %s is using a deprecated SCSI "
221 "ioctl, please convert it to SG_IO\n", current->comm);
222 break;
223 default:
224 break;
225 }
226
227 switch (cmd) {
228 case SCSI_IOCTL_GET_IDLUN:
229 if (!access_ok(VERIFY_WRITE, arg, sizeof(struct scsi_idlun)))
230 return -EFAULT;
231
232 __put_user((sdev->id & 0xff)
233 + ((sdev->lun & 0xff) << 8)
234 + ((sdev->channel & 0xff) << 16)
235 + ((sdev->host->host_no & 0xff) << 24),
236 &((struct scsi_idlun __user *)arg)->dev_id);
237 __put_user(sdev->host->unique_id,
238 &((struct scsi_idlun __user *)arg)->host_unique_id);
239 return 0;
240 case SCSI_IOCTL_GET_BUS_NUMBER:
241 return put_user(sdev->host->host_no, (int __user *)arg);
242 case SCSI_IOCTL_PROBE_HOST:
243 return ioctl_probe(sdev->host, arg);
244 case SCSI_IOCTL_SEND_COMMAND:
245 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
246 return -EACCES;
247 return sg_scsi_ioctl(sdev->request_queue, NULL, 0, arg);
248 case SCSI_IOCTL_DOORLOCK:
249 return scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
250 case SCSI_IOCTL_DOORUNLOCK:
251 return scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
252 case SCSI_IOCTL_TEST_UNIT_READY:
253 return scsi_test_unit_ready(sdev, IOCTL_NORMAL_TIMEOUT,
254 NORMAL_RETRIES, NULL);
255 case SCSI_IOCTL_START_UNIT:
256 scsi_cmd[0] = START_STOP;
257 scsi_cmd[1] = 0;
258 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
259 scsi_cmd[4] = 1;
260 return ioctl_internal_command(sdev, scsi_cmd,
261 START_STOP_TIMEOUT, NORMAL_RETRIES);
262 case SCSI_IOCTL_STOP_UNIT:
263 scsi_cmd[0] = START_STOP;
264 scsi_cmd[1] = 0;
265 scsi_cmd[2] = scsi_cmd[3] = scsi_cmd[5] = 0;
266 scsi_cmd[4] = 0;
267 return ioctl_internal_command(sdev, scsi_cmd,
268 START_STOP_TIMEOUT, NORMAL_RETRIES);
269 case SCSI_IOCTL_GET_PCI:
270 return scsi_ioctl_get_pci(sdev, arg);
271 default:
272 if (sdev->host->hostt->ioctl)
273 return sdev->host->hostt->ioctl(sdev, cmd, arg);
274 }
275 return -EINVAL;
276 }
277 EXPORT_SYMBOL(scsi_ioctl);
278
279 /**
280 * scsi_nonblockable_ioctl() - Handle SG_SCSI_RESET
281 * @sdev: scsi device receiving ioctl
282 * @cmd: Must be SC_SCSI_RESET
283 * @arg: pointer to int containing SG_SCSI_RESET_{DEVICE,BUS,HOST}
284 * @ndelay: file mode O_NDELAY flag
285 */
scsi_nonblockable_ioctl(struct scsi_device * sdev,int cmd,void __user * arg,int ndelay)286 int scsi_nonblockable_ioctl(struct scsi_device *sdev, int cmd,
287 void __user *arg, int ndelay)
288 {
289 int val, result;
290
291 /* The first set of iocts may be executed even if we're doing
292 * error processing, as long as the device was opened
293 * non-blocking */
294 if (ndelay) {
295 if (scsi_host_in_recovery(sdev->host))
296 return -ENODEV;
297 } else if (!scsi_block_when_processing_errors(sdev))
298 return -ENODEV;
299
300 switch (cmd) {
301 case SG_SCSI_RESET:
302 result = get_user(val, (int __user *)arg);
303 if (result)
304 return result;
305 if (val == SG_SCSI_RESET_NOTHING)
306 return 0;
307 switch (val) {
308 case SG_SCSI_RESET_DEVICE:
309 val = SCSI_TRY_RESET_DEVICE;
310 break;
311 case SG_SCSI_RESET_TARGET:
312 val = SCSI_TRY_RESET_TARGET;
313 break;
314 case SG_SCSI_RESET_BUS:
315 val = SCSI_TRY_RESET_BUS;
316 break;
317 case SG_SCSI_RESET_HOST:
318 val = SCSI_TRY_RESET_HOST;
319 break;
320 default:
321 return -EINVAL;
322 }
323 if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO))
324 return -EACCES;
325 return (scsi_reset_provider(sdev, val) ==
326 SUCCESS) ? 0 : -EIO;
327 }
328 return -ENODEV;
329 }
330 EXPORT_SYMBOL(scsi_nonblockable_ioctl);
331