1 /*
2 * Copyright (c) 2007, 2008, 2009 QLogic Corporation. All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses. You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
9 *
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
12 * conditions are met:
13 *
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer.
17 *
18 * - Redistributions in binary form must reproduce the above
19 * copyright notice, this list of conditions and the following
20 * disclaimer in the documentation and/or other materials
21 * provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 */
32 #include <linux/mm.h>
33 #include <linux/types.h>
34 #include <linux/device.h>
35 #include <linux/dmapool.h>
36 #include <linux/slab.h>
37 #include <linux/list.h>
38 #include <linux/highmem.h>
39 #include <linux/io.h>
40 #include <linux/uio.h>
41 #include <linux/rbtree.h>
42 #include <linux/spinlock.h>
43 #include <linux/delay.h>
44
45 #include "qib.h"
46 #include "qib_user_sdma.h"
47
48 /* minimum size of header */
49 #define QIB_USER_SDMA_MIN_HEADER_LENGTH 64
50 /* expected size of headers (for dma_pool) */
51 #define QIB_USER_SDMA_EXP_HEADER_LENGTH 64
52 /* attempt to drain the queue for 5secs */
53 #define QIB_USER_SDMA_DRAIN_TIMEOUT 250
54
55 /*
56 * track how many times a process open this driver.
57 */
58 static struct rb_root qib_user_sdma_rb_root = RB_ROOT;
59
60 struct qib_user_sdma_rb_node {
61 struct rb_node node;
62 int refcount;
63 pid_t pid;
64 };
65
66 struct qib_user_sdma_pkt {
67 struct list_head list; /* list element */
68
69 u8 tiddma; /* if this is NEW tid-sdma */
70 u8 largepkt; /* this is large pkt from kmalloc */
71 u16 frag_size; /* frag size used by PSM */
72 u16 index; /* last header index or push index */
73 u16 naddr; /* dimension of addr (1..3) ... */
74 u16 addrlimit; /* addr array size */
75 u16 tidsmidx; /* current tidsm index */
76 u16 tidsmcount; /* tidsm array item count */
77 u16 payload_size; /* payload size so far for header */
78 u32 bytes_togo; /* bytes for processing */
79 u32 counter; /* sdma pkts queued counter for this entry */
80 struct qib_tid_session_member *tidsm; /* tid session member array */
81 struct qib_user_sdma_queue *pq; /* which pq this pkt belongs to */
82 u64 added; /* global descq number of entries */
83
84 struct {
85 u16 offset; /* offset for kvaddr, addr */
86 u16 length; /* length in page */
87 u16 first_desc; /* first desc */
88 u16 last_desc; /* last desc */
89 u16 put_page; /* should we put_page? */
90 u16 dma_mapped; /* is page dma_mapped? */
91 u16 dma_length; /* for dma_unmap_page() */
92 u16 padding;
93 struct page *page; /* may be NULL (coherent mem) */
94 void *kvaddr; /* FIXME: only for pio hack */
95 dma_addr_t addr;
96 } addr[4]; /* max pages, any more and we coalesce */
97 };
98
99 struct qib_user_sdma_queue {
100 /*
101 * pkts sent to dma engine are queued on this
102 * list head. the type of the elements of this
103 * list are struct qib_user_sdma_pkt...
104 */
105 struct list_head sent;
106
107 /*
108 * Because above list will be accessed by both process and
109 * signal handler, we need a spinlock for it.
110 */
111 spinlock_t sent_lock ____cacheline_aligned_in_smp;
112
113 /* headers with expected length are allocated from here... */
114 char header_cache_name[64];
115 struct dma_pool *header_cache;
116
117 /* packets are allocated from the slab cache... */
118 char pkt_slab_name[64];
119 struct kmem_cache *pkt_slab;
120
121 /* as packets go on the queued queue, they are counted... */
122 u32 counter;
123 u32 sent_counter;
124 /* pending packets, not sending yet */
125 u32 num_pending;
126 /* sending packets, not complete yet */
127 u32 num_sending;
128 /* global descq number of entry of last sending packet */
129 u64 added;
130
131 /* dma page table */
132 struct rb_root dma_pages_root;
133
134 struct qib_user_sdma_rb_node *sdma_rb_node;
135
136 /* protect everything above... */
137 struct mutex lock;
138 };
139
140 static struct qib_user_sdma_rb_node *
qib_user_sdma_rb_search(struct rb_root * root,pid_t pid)141 qib_user_sdma_rb_search(struct rb_root *root, pid_t pid)
142 {
143 struct qib_user_sdma_rb_node *sdma_rb_node;
144 struct rb_node *node = root->rb_node;
145
146 while (node) {
147 sdma_rb_node = rb_entry(node, struct qib_user_sdma_rb_node,
148 node);
149 if (pid < sdma_rb_node->pid)
150 node = node->rb_left;
151 else if (pid > sdma_rb_node->pid)
152 node = node->rb_right;
153 else
154 return sdma_rb_node;
155 }
156 return NULL;
157 }
158
159 static int
qib_user_sdma_rb_insert(struct rb_root * root,struct qib_user_sdma_rb_node * new)160 qib_user_sdma_rb_insert(struct rb_root *root, struct qib_user_sdma_rb_node *new)
161 {
162 struct rb_node **node = &(root->rb_node);
163 struct rb_node *parent = NULL;
164 struct qib_user_sdma_rb_node *got;
165
166 while (*node) {
167 got = rb_entry(*node, struct qib_user_sdma_rb_node, node);
168 parent = *node;
169 if (new->pid < got->pid)
170 node = &((*node)->rb_left);
171 else if (new->pid > got->pid)
172 node = &((*node)->rb_right);
173 else
174 return 0;
175 }
176
177 rb_link_node(&new->node, parent, node);
178 rb_insert_color(&new->node, root);
179 return 1;
180 }
181
182 struct qib_user_sdma_queue *
qib_user_sdma_queue_create(struct device * dev,int unit,int ctxt,int sctxt)183 qib_user_sdma_queue_create(struct device *dev, int unit, int ctxt, int sctxt)
184 {
185 struct qib_user_sdma_queue *pq =
186 kmalloc(sizeof(struct qib_user_sdma_queue), GFP_KERNEL);
187 struct qib_user_sdma_rb_node *sdma_rb_node;
188
189 if (!pq)
190 goto done;
191
192 pq->counter = 0;
193 pq->sent_counter = 0;
194 pq->num_pending = 0;
195 pq->num_sending = 0;
196 pq->added = 0;
197 pq->sdma_rb_node = NULL;
198
199 INIT_LIST_HEAD(&pq->sent);
200 spin_lock_init(&pq->sent_lock);
201 mutex_init(&pq->lock);
202
203 snprintf(pq->pkt_slab_name, sizeof(pq->pkt_slab_name),
204 "qib-user-sdma-pkts-%u-%02u.%02u", unit, ctxt, sctxt);
205 pq->pkt_slab = kmem_cache_create(pq->pkt_slab_name,
206 sizeof(struct qib_user_sdma_pkt),
207 0, 0, NULL);
208
209 if (!pq->pkt_slab)
210 goto err_kfree;
211
212 snprintf(pq->header_cache_name, sizeof(pq->header_cache_name),
213 "qib-user-sdma-headers-%u-%02u.%02u", unit, ctxt, sctxt);
214 pq->header_cache = dma_pool_create(pq->header_cache_name,
215 dev,
216 QIB_USER_SDMA_EXP_HEADER_LENGTH,
217 4, 0);
218 if (!pq->header_cache)
219 goto err_slab;
220
221 pq->dma_pages_root = RB_ROOT;
222
223 sdma_rb_node = qib_user_sdma_rb_search(&qib_user_sdma_rb_root,
224 current->pid);
225 if (sdma_rb_node) {
226 sdma_rb_node->refcount++;
227 } else {
228 sdma_rb_node = kmalloc(sizeof(
229 struct qib_user_sdma_rb_node), GFP_KERNEL);
230 if (!sdma_rb_node)
231 goto err_rb;
232
233 sdma_rb_node->refcount = 1;
234 sdma_rb_node->pid = current->pid;
235
236 qib_user_sdma_rb_insert(&qib_user_sdma_rb_root, sdma_rb_node);
237 }
238 pq->sdma_rb_node = sdma_rb_node;
239
240 goto done;
241
242 err_rb:
243 dma_pool_destroy(pq->header_cache);
244 err_slab:
245 kmem_cache_destroy(pq->pkt_slab);
246 err_kfree:
247 kfree(pq);
248 pq = NULL;
249
250 done:
251 return pq;
252 }
253
qib_user_sdma_init_frag(struct qib_user_sdma_pkt * pkt,int i,u16 offset,u16 len,u16 first_desc,u16 last_desc,u16 put_page,u16 dma_mapped,struct page * page,void * kvaddr,dma_addr_t dma_addr,u16 dma_length)254 static void qib_user_sdma_init_frag(struct qib_user_sdma_pkt *pkt,
255 int i, u16 offset, u16 len,
256 u16 first_desc, u16 last_desc,
257 u16 put_page, u16 dma_mapped,
258 struct page *page, void *kvaddr,
259 dma_addr_t dma_addr, u16 dma_length)
260 {
261 pkt->addr[i].offset = offset;
262 pkt->addr[i].length = len;
263 pkt->addr[i].first_desc = first_desc;
264 pkt->addr[i].last_desc = last_desc;
265 pkt->addr[i].put_page = put_page;
266 pkt->addr[i].dma_mapped = dma_mapped;
267 pkt->addr[i].page = page;
268 pkt->addr[i].kvaddr = kvaddr;
269 pkt->addr[i].addr = dma_addr;
270 pkt->addr[i].dma_length = dma_length;
271 }
272
qib_user_sdma_alloc_header(struct qib_user_sdma_queue * pq,size_t len,dma_addr_t * dma_addr)273 static void *qib_user_sdma_alloc_header(struct qib_user_sdma_queue *pq,
274 size_t len, dma_addr_t *dma_addr)
275 {
276 void *hdr;
277
278 if (len == QIB_USER_SDMA_EXP_HEADER_LENGTH)
279 hdr = dma_pool_alloc(pq->header_cache, GFP_KERNEL,
280 dma_addr);
281 else
282 hdr = NULL;
283
284 if (!hdr) {
285 hdr = kmalloc(len, GFP_KERNEL);
286 if (!hdr)
287 return NULL;
288
289 *dma_addr = 0;
290 }
291
292 return hdr;
293 }
294
qib_user_sdma_page_to_frags(const struct qib_devdata * dd,struct qib_user_sdma_queue * pq,struct qib_user_sdma_pkt * pkt,struct page * page,u16 put,u16 offset,u16 len,void * kvaddr)295 static int qib_user_sdma_page_to_frags(const struct qib_devdata *dd,
296 struct qib_user_sdma_queue *pq,
297 struct qib_user_sdma_pkt *pkt,
298 struct page *page, u16 put,
299 u16 offset, u16 len, void *kvaddr)
300 {
301 __le16 *pbc16;
302 void *pbcvaddr;
303 struct qib_message_header *hdr;
304 u16 newlen, pbclen, lastdesc, dma_mapped;
305 u32 vcto;
306 union qib_seqnum seqnum;
307 dma_addr_t pbcdaddr;
308 dma_addr_t dma_addr =
309 dma_map_page(&dd->pcidev->dev,
310 page, offset, len, DMA_TO_DEVICE);
311 int ret = 0;
312
313 if (dma_mapping_error(&dd->pcidev->dev, dma_addr)) {
314 /*
315 * dma mapping error, pkt has not managed
316 * this page yet, return the page here so
317 * the caller can ignore this page.
318 */
319 if (put) {
320 unpin_user_page(page);
321 } else {
322 /* coalesce case */
323 kunmap(page);
324 __free_page(page);
325 }
326 ret = -ENOMEM;
327 goto done;
328 }
329 offset = 0;
330 dma_mapped = 1;
331
332
333 next_fragment:
334
335 /*
336 * In tid-sdma, the transfer length is restricted by
337 * receiver side current tid page length.
338 */
339 if (pkt->tiddma && len > pkt->tidsm[pkt->tidsmidx].length)
340 newlen = pkt->tidsm[pkt->tidsmidx].length;
341 else
342 newlen = len;
343
344 /*
345 * Then the transfer length is restricted by MTU.
346 * the last descriptor flag is determined by:
347 * 1. the current packet is at frag size length.
348 * 2. the current tid page is done if tid-sdma.
349 * 3. there is no more byte togo if sdma.
350 */
351 lastdesc = 0;
352 if ((pkt->payload_size + newlen) >= pkt->frag_size) {
353 newlen = pkt->frag_size - pkt->payload_size;
354 lastdesc = 1;
355 } else if (pkt->tiddma) {
356 if (newlen == pkt->tidsm[pkt->tidsmidx].length)
357 lastdesc = 1;
358 } else {
359 if (newlen == pkt->bytes_togo)
360 lastdesc = 1;
361 }
362
363 /* fill the next fragment in this page */
364 qib_user_sdma_init_frag(pkt, pkt->naddr, /* index */
365 offset, newlen, /* offset, len */
366 0, lastdesc, /* first last desc */
367 put, dma_mapped, /* put page, dma mapped */
368 page, kvaddr, /* struct page, virt addr */
369 dma_addr, len); /* dma addr, dma length */
370 pkt->bytes_togo -= newlen;
371 pkt->payload_size += newlen;
372 pkt->naddr++;
373 if (pkt->naddr == pkt->addrlimit) {
374 ret = -EFAULT;
375 goto done;
376 }
377
378 /* If there is no more byte togo. (lastdesc==1) */
379 if (pkt->bytes_togo == 0) {
380 /* The packet is done, header is not dma mapped yet.
381 * it should be from kmalloc */
382 if (!pkt->addr[pkt->index].addr) {
383 pkt->addr[pkt->index].addr =
384 dma_map_single(&dd->pcidev->dev,
385 pkt->addr[pkt->index].kvaddr,
386 pkt->addr[pkt->index].dma_length,
387 DMA_TO_DEVICE);
388 if (dma_mapping_error(&dd->pcidev->dev,
389 pkt->addr[pkt->index].addr)) {
390 ret = -ENOMEM;
391 goto done;
392 }
393 pkt->addr[pkt->index].dma_mapped = 1;
394 }
395
396 goto done;
397 }
398
399 /* If tid-sdma, advance tid info. */
400 if (pkt->tiddma) {
401 pkt->tidsm[pkt->tidsmidx].length -= newlen;
402 if (pkt->tidsm[pkt->tidsmidx].length) {
403 pkt->tidsm[pkt->tidsmidx].offset += newlen;
404 } else {
405 pkt->tidsmidx++;
406 if (pkt->tidsmidx == pkt->tidsmcount) {
407 ret = -EFAULT;
408 goto done;
409 }
410 }
411 }
412
413 /*
414 * If this is NOT the last descriptor. (newlen==len)
415 * the current packet is not done yet, but the current
416 * send side page is done.
417 */
418 if (lastdesc == 0)
419 goto done;
420
421 /*
422 * If running this driver under PSM with message size
423 * fitting into one transfer unit, it is not possible
424 * to pass this line. otherwise, it is a buggggg.
425 */
426
427 /*
428 * Since the current packet is done, and there are more
429 * bytes togo, we need to create a new sdma header, copying
430 * from previous sdma header and modify both.
431 */
432 pbclen = pkt->addr[pkt->index].length;
433 pbcvaddr = qib_user_sdma_alloc_header(pq, pbclen, &pbcdaddr);
434 if (!pbcvaddr) {
435 ret = -ENOMEM;
436 goto done;
437 }
438 /* Copy the previous sdma header to new sdma header */
439 pbc16 = (__le16 *)pkt->addr[pkt->index].kvaddr;
440 memcpy(pbcvaddr, pbc16, pbclen);
441
442 /* Modify the previous sdma header */
443 hdr = (struct qib_message_header *)&pbc16[4];
444
445 /* New pbc length */
446 pbc16[0] = cpu_to_le16(le16_to_cpu(pbc16[0])-(pkt->bytes_togo>>2));
447
448 /* New packet length */
449 hdr->lrh[2] = cpu_to_be16(le16_to_cpu(pbc16[0]));
450
451 if (pkt->tiddma) {
452 /* turn on the header suppression */
453 hdr->iph.pkt_flags =
454 cpu_to_le16(le16_to_cpu(hdr->iph.pkt_flags)|0x2);
455 /* turn off ACK_REQ: 0x04 and EXPECTED_DONE: 0x20 */
456 hdr->flags &= ~(0x04|0x20);
457 } else {
458 /* turn off extra bytes: 20-21 bits */
459 hdr->bth[0] = cpu_to_be32(be32_to_cpu(hdr->bth[0])&0xFFCFFFFF);
460 /* turn off ACK_REQ: 0x04 */
461 hdr->flags &= ~(0x04);
462 }
463
464 /* New kdeth checksum */
465 vcto = le32_to_cpu(hdr->iph.ver_ctxt_tid_offset);
466 hdr->iph.chksum = cpu_to_le16(QIB_LRH_BTH +
467 be16_to_cpu(hdr->lrh[2]) -
468 ((vcto>>16)&0xFFFF) - (vcto&0xFFFF) -
469 le16_to_cpu(hdr->iph.pkt_flags));
470
471 /* The packet is done, header is not dma mapped yet.
472 * it should be from kmalloc */
473 if (!pkt->addr[pkt->index].addr) {
474 pkt->addr[pkt->index].addr =
475 dma_map_single(&dd->pcidev->dev,
476 pkt->addr[pkt->index].kvaddr,
477 pkt->addr[pkt->index].dma_length,
478 DMA_TO_DEVICE);
479 if (dma_mapping_error(&dd->pcidev->dev,
480 pkt->addr[pkt->index].addr)) {
481 ret = -ENOMEM;
482 goto done;
483 }
484 pkt->addr[pkt->index].dma_mapped = 1;
485 }
486
487 /* Modify the new sdma header */
488 pbc16 = (__le16 *)pbcvaddr;
489 hdr = (struct qib_message_header *)&pbc16[4];
490
491 /* New pbc length */
492 pbc16[0] = cpu_to_le16(le16_to_cpu(pbc16[0])-(pkt->payload_size>>2));
493
494 /* New packet length */
495 hdr->lrh[2] = cpu_to_be16(le16_to_cpu(pbc16[0]));
496
497 if (pkt->tiddma) {
498 /* Set new tid and offset for new sdma header */
499 hdr->iph.ver_ctxt_tid_offset = cpu_to_le32(
500 (le32_to_cpu(hdr->iph.ver_ctxt_tid_offset)&0xFF000000) +
501 (pkt->tidsm[pkt->tidsmidx].tid<<QLOGIC_IB_I_TID_SHIFT) +
502 (pkt->tidsm[pkt->tidsmidx].offset>>2));
503 } else {
504 /* Middle protocol new packet offset */
505 hdr->uwords[2] += pkt->payload_size;
506 }
507
508 /* New kdeth checksum */
509 vcto = le32_to_cpu(hdr->iph.ver_ctxt_tid_offset);
510 hdr->iph.chksum = cpu_to_le16(QIB_LRH_BTH +
511 be16_to_cpu(hdr->lrh[2]) -
512 ((vcto>>16)&0xFFFF) - (vcto&0xFFFF) -
513 le16_to_cpu(hdr->iph.pkt_flags));
514
515 /* Next sequence number in new sdma header */
516 seqnum.val = be32_to_cpu(hdr->bth[2]);
517 if (pkt->tiddma)
518 seqnum.seq++;
519 else
520 seqnum.pkt++;
521 hdr->bth[2] = cpu_to_be32(seqnum.val);
522
523 /* Init new sdma header. */
524 qib_user_sdma_init_frag(pkt, pkt->naddr, /* index */
525 0, pbclen, /* offset, len */
526 1, 0, /* first last desc */
527 0, 0, /* put page, dma mapped */
528 NULL, pbcvaddr, /* struct page, virt addr */
529 pbcdaddr, pbclen); /* dma addr, dma length */
530 pkt->index = pkt->naddr;
531 pkt->payload_size = 0;
532 pkt->naddr++;
533 if (pkt->naddr == pkt->addrlimit) {
534 ret = -EFAULT;
535 goto done;
536 }
537
538 /* Prepare for next fragment in this page */
539 if (newlen != len) {
540 if (dma_mapped) {
541 put = 0;
542 dma_mapped = 0;
543 page = NULL;
544 kvaddr = NULL;
545 }
546 len -= newlen;
547 offset += newlen;
548
549 goto next_fragment;
550 }
551
552 done:
553 return ret;
554 }
555
556 /* we've too many pages in the iovec, coalesce to a single page */
qib_user_sdma_coalesce(const struct qib_devdata * dd,struct qib_user_sdma_queue * pq,struct qib_user_sdma_pkt * pkt,const struct iovec * iov,unsigned long niov)557 static int qib_user_sdma_coalesce(const struct qib_devdata *dd,
558 struct qib_user_sdma_queue *pq,
559 struct qib_user_sdma_pkt *pkt,
560 const struct iovec *iov,
561 unsigned long niov)
562 {
563 int ret = 0;
564 struct page *page = alloc_page(GFP_KERNEL);
565 void *mpage_save;
566 char *mpage;
567 int i;
568 int len = 0;
569
570 if (!page) {
571 ret = -ENOMEM;
572 goto done;
573 }
574
575 mpage = kmap(page);
576 mpage_save = mpage;
577 for (i = 0; i < niov; i++) {
578 int cfur;
579
580 cfur = copy_from_user(mpage,
581 iov[i].iov_base, iov[i].iov_len);
582 if (cfur) {
583 ret = -EFAULT;
584 goto free_unmap;
585 }
586
587 mpage += iov[i].iov_len;
588 len += iov[i].iov_len;
589 }
590
591 ret = qib_user_sdma_page_to_frags(dd, pq, pkt,
592 page, 0, 0, len, mpage_save);
593 goto done;
594
595 free_unmap:
596 kunmap(page);
597 __free_page(page);
598 done:
599 return ret;
600 }
601
602 /*
603 * How many pages in this iovec element?
604 */
qib_user_sdma_num_pages(const struct iovec * iov)605 static size_t qib_user_sdma_num_pages(const struct iovec *iov)
606 {
607 const unsigned long addr = (unsigned long) iov->iov_base;
608 const unsigned long len = iov->iov_len;
609 const unsigned long spage = addr & PAGE_MASK;
610 const unsigned long epage = (addr + len - 1) & PAGE_MASK;
611
612 return 1 + ((epage - spage) >> PAGE_SHIFT);
613 }
614
qib_user_sdma_free_pkt_frag(struct device * dev,struct qib_user_sdma_queue * pq,struct qib_user_sdma_pkt * pkt,int frag)615 static void qib_user_sdma_free_pkt_frag(struct device *dev,
616 struct qib_user_sdma_queue *pq,
617 struct qib_user_sdma_pkt *pkt,
618 int frag)
619 {
620 const int i = frag;
621
622 if (pkt->addr[i].page) {
623 /* only user data has page */
624 if (pkt->addr[i].dma_mapped)
625 dma_unmap_page(dev,
626 pkt->addr[i].addr,
627 pkt->addr[i].dma_length,
628 DMA_TO_DEVICE);
629
630 if (pkt->addr[i].kvaddr)
631 kunmap(pkt->addr[i].page);
632
633 if (pkt->addr[i].put_page)
634 unpin_user_page(pkt->addr[i].page);
635 else
636 __free_page(pkt->addr[i].page);
637 } else if (pkt->addr[i].kvaddr) {
638 /* for headers */
639 if (pkt->addr[i].dma_mapped) {
640 /* from kmalloc & dma mapped */
641 dma_unmap_single(dev,
642 pkt->addr[i].addr,
643 pkt->addr[i].dma_length,
644 DMA_TO_DEVICE);
645 kfree(pkt->addr[i].kvaddr);
646 } else if (pkt->addr[i].addr) {
647 /* free coherent mem from cache... */
648 dma_pool_free(pq->header_cache,
649 pkt->addr[i].kvaddr, pkt->addr[i].addr);
650 } else {
651 /* from kmalloc but not dma mapped */
652 kfree(pkt->addr[i].kvaddr);
653 }
654 }
655 }
656
657 /* return number of pages pinned... */
qib_user_sdma_pin_pages(const struct qib_devdata * dd,struct qib_user_sdma_queue * pq,struct qib_user_sdma_pkt * pkt,unsigned long addr,int tlen,size_t npages)658 static int qib_user_sdma_pin_pages(const struct qib_devdata *dd,
659 struct qib_user_sdma_queue *pq,
660 struct qib_user_sdma_pkt *pkt,
661 unsigned long addr, int tlen, size_t npages)
662 {
663 struct page *pages[8];
664 int i, j;
665 int ret = 0;
666
667 while (npages) {
668 if (npages > 8)
669 j = 8;
670 else
671 j = npages;
672
673 ret = pin_user_pages_fast(addr, j, FOLL_LONGTERM, pages);
674 if (ret != j) {
675 i = 0;
676 j = ret;
677 ret = -ENOMEM;
678 goto free_pages;
679 }
680
681 for (i = 0; i < j; i++) {
682 /* map the pages... */
683 unsigned long fofs = addr & ~PAGE_MASK;
684 int flen = ((fofs + tlen) > PAGE_SIZE) ?
685 (PAGE_SIZE - fofs) : tlen;
686
687 ret = qib_user_sdma_page_to_frags(dd, pq, pkt,
688 pages[i], 1, fofs, flen, NULL);
689 if (ret < 0) {
690 /* current page has beed taken
691 * care of inside above call.
692 */
693 i++;
694 goto free_pages;
695 }
696
697 addr += flen;
698 tlen -= flen;
699 }
700
701 npages -= j;
702 }
703
704 goto done;
705
706 /* if error, return all pages not managed by pkt */
707 free_pages:
708 while (i < j)
709 unpin_user_page(pages[i++]);
710
711 done:
712 return ret;
713 }
714
qib_user_sdma_pin_pkt(const struct qib_devdata * dd,struct qib_user_sdma_queue * pq,struct qib_user_sdma_pkt * pkt,const struct iovec * iov,unsigned long niov)715 static int qib_user_sdma_pin_pkt(const struct qib_devdata *dd,
716 struct qib_user_sdma_queue *pq,
717 struct qib_user_sdma_pkt *pkt,
718 const struct iovec *iov,
719 unsigned long niov)
720 {
721 int ret = 0;
722 unsigned long idx;
723
724 for (idx = 0; idx < niov; idx++) {
725 const size_t npages = qib_user_sdma_num_pages(iov + idx);
726 const unsigned long addr = (unsigned long) iov[idx].iov_base;
727
728 ret = qib_user_sdma_pin_pages(dd, pq, pkt, addr,
729 iov[idx].iov_len, npages);
730 if (ret < 0)
731 goto free_pkt;
732 }
733
734 goto done;
735
736 free_pkt:
737 /* we need to ignore the first entry here */
738 for (idx = 1; idx < pkt->naddr; idx++)
739 qib_user_sdma_free_pkt_frag(&dd->pcidev->dev, pq, pkt, idx);
740
741 /* need to dma unmap the first entry, this is to restore to
742 * the original state so that caller can free the memory in
743 * error condition. Caller does not know if dma mapped or not*/
744 if (pkt->addr[0].dma_mapped) {
745 dma_unmap_single(&dd->pcidev->dev,
746 pkt->addr[0].addr,
747 pkt->addr[0].dma_length,
748 DMA_TO_DEVICE);
749 pkt->addr[0].addr = 0;
750 pkt->addr[0].dma_mapped = 0;
751 }
752
753 done:
754 return ret;
755 }
756
qib_user_sdma_init_payload(const struct qib_devdata * dd,struct qib_user_sdma_queue * pq,struct qib_user_sdma_pkt * pkt,const struct iovec * iov,unsigned long niov,int npages)757 static int qib_user_sdma_init_payload(const struct qib_devdata *dd,
758 struct qib_user_sdma_queue *pq,
759 struct qib_user_sdma_pkt *pkt,
760 const struct iovec *iov,
761 unsigned long niov, int npages)
762 {
763 int ret = 0;
764
765 if (pkt->frag_size == pkt->bytes_togo &&
766 npages >= ARRAY_SIZE(pkt->addr))
767 ret = qib_user_sdma_coalesce(dd, pq, pkt, iov, niov);
768 else
769 ret = qib_user_sdma_pin_pkt(dd, pq, pkt, iov, niov);
770
771 return ret;
772 }
773
774 /* free a packet list -- return counter value of last packet */
qib_user_sdma_free_pkt_list(struct device * dev,struct qib_user_sdma_queue * pq,struct list_head * list)775 static void qib_user_sdma_free_pkt_list(struct device *dev,
776 struct qib_user_sdma_queue *pq,
777 struct list_head *list)
778 {
779 struct qib_user_sdma_pkt *pkt, *pkt_next;
780
781 list_for_each_entry_safe(pkt, pkt_next, list, list) {
782 int i;
783
784 for (i = 0; i < pkt->naddr; i++)
785 qib_user_sdma_free_pkt_frag(dev, pq, pkt, i);
786
787 if (pkt->largepkt)
788 kfree(pkt);
789 else
790 kmem_cache_free(pq->pkt_slab, pkt);
791 }
792 INIT_LIST_HEAD(list);
793 }
794
795 /*
796 * copy headers, coalesce etc -- pq->lock must be held
797 *
798 * we queue all the packets to list, returning the
799 * number of bytes total. list must be empty initially,
800 * as, if there is an error we clean it...
801 */
qib_user_sdma_queue_pkts(const struct qib_devdata * dd,struct qib_pportdata * ppd,struct qib_user_sdma_queue * pq,const struct iovec * iov,unsigned long niov,struct list_head * list,int * maxpkts,int * ndesc)802 static int qib_user_sdma_queue_pkts(const struct qib_devdata *dd,
803 struct qib_pportdata *ppd,
804 struct qib_user_sdma_queue *pq,
805 const struct iovec *iov,
806 unsigned long niov,
807 struct list_head *list,
808 int *maxpkts, int *ndesc)
809 {
810 unsigned long idx = 0;
811 int ret = 0;
812 int npkts = 0;
813 __le32 *pbc;
814 dma_addr_t dma_addr;
815 struct qib_user_sdma_pkt *pkt = NULL;
816 size_t len;
817 size_t nw;
818 u32 counter = pq->counter;
819 u16 frag_size;
820
821 while (idx < niov && npkts < *maxpkts) {
822 const unsigned long addr = (unsigned long) iov[idx].iov_base;
823 const unsigned long idx_save = idx;
824 unsigned pktnw;
825 unsigned pktnwc;
826 int nfrags = 0;
827 size_t npages = 0;
828 size_t bytes_togo = 0;
829 int tiddma = 0;
830 int cfur;
831
832 len = iov[idx].iov_len;
833 nw = len >> 2;
834
835 if (len < QIB_USER_SDMA_MIN_HEADER_LENGTH ||
836 len > PAGE_SIZE || len & 3 || addr & 3) {
837 ret = -EINVAL;
838 goto free_list;
839 }
840
841 pbc = qib_user_sdma_alloc_header(pq, len, &dma_addr);
842 if (!pbc) {
843 ret = -ENOMEM;
844 goto free_list;
845 }
846
847 cfur = copy_from_user(pbc, iov[idx].iov_base, len);
848 if (cfur) {
849 ret = -EFAULT;
850 goto free_pbc;
851 }
852
853 /*
854 * This assignment is a bit strange. it's because the
855 * the pbc counts the number of 32 bit words in the full
856 * packet _except_ the first word of the pbc itself...
857 */
858 pktnwc = nw - 1;
859
860 /*
861 * pktnw computation yields the number of 32 bit words
862 * that the caller has indicated in the PBC. note that
863 * this is one less than the total number of words that
864 * goes to the send DMA engine as the first 32 bit word
865 * of the PBC itself is not counted. Armed with this count,
866 * we can verify that the packet is consistent with the
867 * iovec lengths.
868 */
869 pktnw = le32_to_cpu(*pbc) & 0xFFFF;
870 if (pktnw < pktnwc) {
871 ret = -EINVAL;
872 goto free_pbc;
873 }
874
875 idx++;
876 while (pktnwc < pktnw && idx < niov) {
877 const size_t slen = iov[idx].iov_len;
878 const unsigned long faddr =
879 (unsigned long) iov[idx].iov_base;
880
881 if (slen & 3 || faddr & 3 || !slen) {
882 ret = -EINVAL;
883 goto free_pbc;
884 }
885
886 npages += qib_user_sdma_num_pages(&iov[idx]);
887
888 if (check_add_overflow(bytes_togo, slen, &bytes_togo) ||
889 bytes_togo > type_max(typeof(pkt->bytes_togo))) {
890 ret = -EINVAL;
891 goto free_pbc;
892 }
893 pktnwc += slen >> 2;
894 idx++;
895 nfrags++;
896 }
897
898 if (pktnwc != pktnw) {
899 ret = -EINVAL;
900 goto free_pbc;
901 }
902
903 frag_size = ((le32_to_cpu(*pbc))>>16) & 0xFFFF;
904 if (((frag_size ? frag_size : bytes_togo) + len) >
905 ppd->ibmaxlen) {
906 ret = -EINVAL;
907 goto free_pbc;
908 }
909
910 if (frag_size) {
911 size_t tidsmsize, n, pktsize, sz, addrlimit;
912
913 n = npages*((2*PAGE_SIZE/frag_size)+1);
914 pktsize = struct_size(pkt, addr, n);
915
916 /*
917 * Determine if this is tid-sdma or just sdma.
918 */
919 tiddma = (((le32_to_cpu(pbc[7])>>
920 QLOGIC_IB_I_TID_SHIFT)&
921 QLOGIC_IB_I_TID_MASK) !=
922 QLOGIC_IB_I_TID_MASK);
923
924 if (tiddma)
925 tidsmsize = iov[idx].iov_len;
926 else
927 tidsmsize = 0;
928
929 if (check_add_overflow(pktsize, tidsmsize, &sz)) {
930 ret = -EINVAL;
931 goto free_pbc;
932 }
933 pkt = kmalloc(sz, GFP_KERNEL);
934 if (!pkt) {
935 ret = -ENOMEM;
936 goto free_pbc;
937 }
938 pkt->largepkt = 1;
939 pkt->frag_size = frag_size;
940 if (check_add_overflow(n, ARRAY_SIZE(pkt->addr),
941 &addrlimit) ||
942 addrlimit > type_max(typeof(pkt->addrlimit))) {
943 ret = -EINVAL;
944 goto free_pkt;
945 }
946 pkt->addrlimit = addrlimit;
947
948 if (tiddma) {
949 char *tidsm = (char *)pkt + pktsize;
950
951 cfur = copy_from_user(tidsm,
952 iov[idx].iov_base, tidsmsize);
953 if (cfur) {
954 ret = -EFAULT;
955 goto free_pkt;
956 }
957 pkt->tidsm =
958 (struct qib_tid_session_member *)tidsm;
959 pkt->tidsmcount = tidsmsize/
960 sizeof(struct qib_tid_session_member);
961 pkt->tidsmidx = 0;
962 idx++;
963 }
964
965 /*
966 * pbc 'fill1' field is borrowed to pass frag size,
967 * we need to clear it after picking frag size, the
968 * hardware requires this field to be zero.
969 */
970 *pbc = cpu_to_le32(le32_to_cpu(*pbc) & 0x0000FFFF);
971 } else {
972 pkt = kmem_cache_alloc(pq->pkt_slab, GFP_KERNEL);
973 if (!pkt) {
974 ret = -ENOMEM;
975 goto free_pbc;
976 }
977 pkt->largepkt = 0;
978 pkt->frag_size = bytes_togo;
979 pkt->addrlimit = ARRAY_SIZE(pkt->addr);
980 }
981 pkt->bytes_togo = bytes_togo;
982 pkt->payload_size = 0;
983 pkt->counter = counter;
984 pkt->tiddma = tiddma;
985
986 /* setup the first header */
987 qib_user_sdma_init_frag(pkt, 0, /* index */
988 0, len, /* offset, len */
989 1, 0, /* first last desc */
990 0, 0, /* put page, dma mapped */
991 NULL, pbc, /* struct page, virt addr */
992 dma_addr, len); /* dma addr, dma length */
993 pkt->index = 0;
994 pkt->naddr = 1;
995
996 if (nfrags) {
997 ret = qib_user_sdma_init_payload(dd, pq, pkt,
998 iov + idx_save + 1,
999 nfrags, npages);
1000 if (ret < 0)
1001 goto free_pkt;
1002 } else {
1003 /* since there is no payload, mark the
1004 * header as the last desc. */
1005 pkt->addr[0].last_desc = 1;
1006
1007 if (dma_addr == 0) {
1008 /*
1009 * the header is not dma mapped yet.
1010 * it should be from kmalloc.
1011 */
1012 dma_addr = dma_map_single(&dd->pcidev->dev,
1013 pbc, len, DMA_TO_DEVICE);
1014 if (dma_mapping_error(&dd->pcidev->dev,
1015 dma_addr)) {
1016 ret = -ENOMEM;
1017 goto free_pkt;
1018 }
1019 pkt->addr[0].addr = dma_addr;
1020 pkt->addr[0].dma_mapped = 1;
1021 }
1022 }
1023
1024 counter++;
1025 npkts++;
1026 pkt->pq = pq;
1027 pkt->index = 0; /* reset index for push on hw */
1028 *ndesc += pkt->naddr;
1029
1030 list_add_tail(&pkt->list, list);
1031 }
1032
1033 *maxpkts = npkts;
1034 ret = idx;
1035 goto done;
1036
1037 free_pkt:
1038 if (pkt->largepkt)
1039 kfree(pkt);
1040 else
1041 kmem_cache_free(pq->pkt_slab, pkt);
1042 free_pbc:
1043 if (dma_addr)
1044 dma_pool_free(pq->header_cache, pbc, dma_addr);
1045 else
1046 kfree(pbc);
1047 free_list:
1048 qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, list);
1049 done:
1050 return ret;
1051 }
1052
qib_user_sdma_set_complete_counter(struct qib_user_sdma_queue * pq,u32 c)1053 static void qib_user_sdma_set_complete_counter(struct qib_user_sdma_queue *pq,
1054 u32 c)
1055 {
1056 pq->sent_counter = c;
1057 }
1058
1059 /* try to clean out queue -- needs pq->lock */
qib_user_sdma_queue_clean(struct qib_pportdata * ppd,struct qib_user_sdma_queue * pq)1060 static int qib_user_sdma_queue_clean(struct qib_pportdata *ppd,
1061 struct qib_user_sdma_queue *pq)
1062 {
1063 struct qib_devdata *dd = ppd->dd;
1064 struct list_head free_list;
1065 struct qib_user_sdma_pkt *pkt;
1066 struct qib_user_sdma_pkt *pkt_prev;
1067 unsigned long flags;
1068 int ret = 0;
1069
1070 if (!pq->num_sending)
1071 return 0;
1072
1073 INIT_LIST_HEAD(&free_list);
1074
1075 /*
1076 * We need this spin lock here because interrupt handler
1077 * might modify this list in qib_user_sdma_send_desc(), also
1078 * we can not get interrupted, otherwise it is a deadlock.
1079 */
1080 spin_lock_irqsave(&pq->sent_lock, flags);
1081 list_for_each_entry_safe(pkt, pkt_prev, &pq->sent, list) {
1082 s64 descd = ppd->sdma_descq_removed - pkt->added;
1083
1084 if (descd < 0)
1085 break;
1086
1087 list_move_tail(&pkt->list, &free_list);
1088
1089 /* one more packet cleaned */
1090 ret++;
1091 pq->num_sending--;
1092 }
1093 spin_unlock_irqrestore(&pq->sent_lock, flags);
1094
1095 if (!list_empty(&free_list)) {
1096 u32 counter;
1097
1098 pkt = list_entry(free_list.prev,
1099 struct qib_user_sdma_pkt, list);
1100 counter = pkt->counter;
1101
1102 qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &free_list);
1103 qib_user_sdma_set_complete_counter(pq, counter);
1104 }
1105
1106 return ret;
1107 }
1108
qib_user_sdma_queue_destroy(struct qib_user_sdma_queue * pq)1109 void qib_user_sdma_queue_destroy(struct qib_user_sdma_queue *pq)
1110 {
1111 if (!pq)
1112 return;
1113
1114 pq->sdma_rb_node->refcount--;
1115 if (pq->sdma_rb_node->refcount == 0) {
1116 rb_erase(&pq->sdma_rb_node->node, &qib_user_sdma_rb_root);
1117 kfree(pq->sdma_rb_node);
1118 }
1119 dma_pool_destroy(pq->header_cache);
1120 kmem_cache_destroy(pq->pkt_slab);
1121 kfree(pq);
1122 }
1123
1124 /* clean descriptor queue, returns > 0 if some elements cleaned */
qib_user_sdma_hwqueue_clean(struct qib_pportdata * ppd)1125 static int qib_user_sdma_hwqueue_clean(struct qib_pportdata *ppd)
1126 {
1127 int ret;
1128 unsigned long flags;
1129
1130 spin_lock_irqsave(&ppd->sdma_lock, flags);
1131 ret = qib_sdma_make_progress(ppd);
1132 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1133
1134 return ret;
1135 }
1136
1137 /* we're in close, drain packets so that we can cleanup successfully... */
qib_user_sdma_queue_drain(struct qib_pportdata * ppd,struct qib_user_sdma_queue * pq)1138 void qib_user_sdma_queue_drain(struct qib_pportdata *ppd,
1139 struct qib_user_sdma_queue *pq)
1140 {
1141 struct qib_devdata *dd = ppd->dd;
1142 unsigned long flags;
1143 int i;
1144
1145 if (!pq)
1146 return;
1147
1148 for (i = 0; i < QIB_USER_SDMA_DRAIN_TIMEOUT; i++) {
1149 mutex_lock(&pq->lock);
1150 if (!pq->num_pending && !pq->num_sending) {
1151 mutex_unlock(&pq->lock);
1152 break;
1153 }
1154 qib_user_sdma_hwqueue_clean(ppd);
1155 qib_user_sdma_queue_clean(ppd, pq);
1156 mutex_unlock(&pq->lock);
1157 msleep(20);
1158 }
1159
1160 if (pq->num_pending || pq->num_sending) {
1161 struct qib_user_sdma_pkt *pkt;
1162 struct qib_user_sdma_pkt *pkt_prev;
1163 struct list_head free_list;
1164
1165 mutex_lock(&pq->lock);
1166 spin_lock_irqsave(&ppd->sdma_lock, flags);
1167 /*
1168 * Since we hold sdma_lock, it is safe without sent_lock.
1169 */
1170 if (pq->num_pending) {
1171 list_for_each_entry_safe(pkt, pkt_prev,
1172 &ppd->sdma_userpending, list) {
1173 if (pkt->pq == pq) {
1174 list_move_tail(&pkt->list, &pq->sent);
1175 pq->num_pending--;
1176 pq->num_sending++;
1177 }
1178 }
1179 }
1180 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1181
1182 qib_dev_err(dd, "user sdma lists not empty: forcing!\n");
1183 INIT_LIST_HEAD(&free_list);
1184 list_splice_init(&pq->sent, &free_list);
1185 pq->num_sending = 0;
1186 qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &free_list);
1187 mutex_unlock(&pq->lock);
1188 }
1189 }
1190
qib_sdma_make_desc0(u8 gen,u64 addr,u64 dwlen,u64 dwoffset)1191 static inline __le64 qib_sdma_make_desc0(u8 gen,
1192 u64 addr, u64 dwlen, u64 dwoffset)
1193 {
1194 return cpu_to_le64(/* SDmaPhyAddr[31:0] */
1195 ((addr & 0xfffffffcULL) << 32) |
1196 /* SDmaGeneration[1:0] */
1197 ((gen & 3ULL) << 30) |
1198 /* SDmaDwordCount[10:0] */
1199 ((dwlen & 0x7ffULL) << 16) |
1200 /* SDmaBufOffset[12:2] */
1201 (dwoffset & 0x7ffULL));
1202 }
1203
qib_sdma_make_first_desc0(__le64 descq)1204 static inline __le64 qib_sdma_make_first_desc0(__le64 descq)
1205 {
1206 return descq | cpu_to_le64(1ULL << 12);
1207 }
1208
qib_sdma_make_last_desc0(__le64 descq)1209 static inline __le64 qib_sdma_make_last_desc0(__le64 descq)
1210 {
1211 /* last */ /* dma head */
1212 return descq | cpu_to_le64(1ULL << 11 | 1ULL << 13);
1213 }
1214
qib_sdma_make_desc1(u64 addr)1215 static inline __le64 qib_sdma_make_desc1(u64 addr)
1216 {
1217 /* SDmaPhyAddr[47:32] */
1218 return cpu_to_le64(addr >> 32);
1219 }
1220
qib_user_sdma_send_frag(struct qib_pportdata * ppd,struct qib_user_sdma_pkt * pkt,int idx,unsigned ofs,u16 tail,u8 gen)1221 static void qib_user_sdma_send_frag(struct qib_pportdata *ppd,
1222 struct qib_user_sdma_pkt *pkt, int idx,
1223 unsigned ofs, u16 tail, u8 gen)
1224 {
1225 const u64 addr = (u64) pkt->addr[idx].addr +
1226 (u64) pkt->addr[idx].offset;
1227 const u64 dwlen = (u64) pkt->addr[idx].length / 4;
1228 __le64 *descqp;
1229 __le64 descq0;
1230
1231 descqp = &ppd->sdma_descq[tail].qw[0];
1232
1233 descq0 = qib_sdma_make_desc0(gen, addr, dwlen, ofs);
1234 if (pkt->addr[idx].first_desc)
1235 descq0 = qib_sdma_make_first_desc0(descq0);
1236 if (pkt->addr[idx].last_desc) {
1237 descq0 = qib_sdma_make_last_desc0(descq0);
1238 if (ppd->sdma_intrequest) {
1239 descq0 |= cpu_to_le64(1ULL << 15);
1240 ppd->sdma_intrequest = 0;
1241 }
1242 }
1243
1244 descqp[0] = descq0;
1245 descqp[1] = qib_sdma_make_desc1(addr);
1246 }
1247
qib_user_sdma_send_desc(struct qib_pportdata * ppd,struct list_head * pktlist)1248 void qib_user_sdma_send_desc(struct qib_pportdata *ppd,
1249 struct list_head *pktlist)
1250 {
1251 struct qib_devdata *dd = ppd->dd;
1252 u16 nfree, nsent;
1253 u16 tail, tail_c;
1254 u8 gen, gen_c;
1255
1256 nfree = qib_sdma_descq_freecnt(ppd);
1257 if (!nfree)
1258 return;
1259
1260 retry:
1261 nsent = 0;
1262 tail_c = tail = ppd->sdma_descq_tail;
1263 gen_c = gen = ppd->sdma_generation;
1264 while (!list_empty(pktlist)) {
1265 struct qib_user_sdma_pkt *pkt =
1266 list_entry(pktlist->next, struct qib_user_sdma_pkt,
1267 list);
1268 int i, j, c = 0;
1269 unsigned ofs = 0;
1270 u16 dtail = tail;
1271
1272 for (i = pkt->index; i < pkt->naddr && nfree; i++) {
1273 qib_user_sdma_send_frag(ppd, pkt, i, ofs, tail, gen);
1274 ofs += pkt->addr[i].length >> 2;
1275
1276 if (++tail == ppd->sdma_descq_cnt) {
1277 tail = 0;
1278 ++gen;
1279 ppd->sdma_intrequest = 1;
1280 } else if (tail == (ppd->sdma_descq_cnt>>1)) {
1281 ppd->sdma_intrequest = 1;
1282 }
1283 nfree--;
1284 if (pkt->addr[i].last_desc == 0)
1285 continue;
1286
1287 /*
1288 * If the packet is >= 2KB mtu equivalent, we
1289 * have to use the large buffers, and have to
1290 * mark each descriptor as part of a large
1291 * buffer packet.
1292 */
1293 if (ofs > dd->piosize2kmax_dwords) {
1294 for (j = pkt->index; j <= i; j++) {
1295 ppd->sdma_descq[dtail].qw[0] |=
1296 cpu_to_le64(1ULL << 14);
1297 if (++dtail == ppd->sdma_descq_cnt)
1298 dtail = 0;
1299 }
1300 }
1301 c += i + 1 - pkt->index;
1302 pkt->index = i + 1; /* index for next first */
1303 tail_c = dtail = tail;
1304 gen_c = gen;
1305 ofs = 0; /* reset for next packet */
1306 }
1307
1308 ppd->sdma_descq_added += c;
1309 nsent += c;
1310 if (pkt->index == pkt->naddr) {
1311 pkt->added = ppd->sdma_descq_added;
1312 pkt->pq->added = pkt->added;
1313 pkt->pq->num_pending--;
1314 spin_lock(&pkt->pq->sent_lock);
1315 pkt->pq->num_sending++;
1316 list_move_tail(&pkt->list, &pkt->pq->sent);
1317 spin_unlock(&pkt->pq->sent_lock);
1318 }
1319 if (!nfree || (nsent<<2) > ppd->sdma_descq_cnt)
1320 break;
1321 }
1322
1323 /* advance the tail on the chip if necessary */
1324 if (ppd->sdma_descq_tail != tail_c) {
1325 ppd->sdma_generation = gen_c;
1326 dd->f_sdma_update_tail(ppd, tail_c);
1327 }
1328
1329 if (nfree && !list_empty(pktlist))
1330 goto retry;
1331 }
1332
1333 /* pq->lock must be held, get packets on the wire... */
qib_user_sdma_push_pkts(struct qib_pportdata * ppd,struct qib_user_sdma_queue * pq,struct list_head * pktlist,int count)1334 static int qib_user_sdma_push_pkts(struct qib_pportdata *ppd,
1335 struct qib_user_sdma_queue *pq,
1336 struct list_head *pktlist, int count)
1337 {
1338 unsigned long flags;
1339
1340 if (unlikely(!(ppd->lflags & QIBL_LINKACTIVE)))
1341 return -ECOMM;
1342
1343 /* non-blocking mode */
1344 if (pq->sdma_rb_node->refcount > 1) {
1345 spin_lock_irqsave(&ppd->sdma_lock, flags);
1346 if (unlikely(!__qib_sdma_running(ppd))) {
1347 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1348 return -ECOMM;
1349 }
1350 pq->num_pending += count;
1351 list_splice_tail_init(pktlist, &ppd->sdma_userpending);
1352 qib_user_sdma_send_desc(ppd, &ppd->sdma_userpending);
1353 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1354 return 0;
1355 }
1356
1357 /* In this case, descriptors from this process are not
1358 * linked to ppd pending queue, interrupt handler
1359 * won't update this process, it is OK to directly
1360 * modify without sdma lock.
1361 */
1362
1363
1364 pq->num_pending += count;
1365 /*
1366 * Blocking mode for single rail process, we must
1367 * release/regain sdma_lock to give other process
1368 * chance to make progress. This is important for
1369 * performance.
1370 */
1371 do {
1372 spin_lock_irqsave(&ppd->sdma_lock, flags);
1373 if (unlikely(!__qib_sdma_running(ppd))) {
1374 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1375 return -ECOMM;
1376 }
1377 qib_user_sdma_send_desc(ppd, pktlist);
1378 if (!list_empty(pktlist))
1379 qib_sdma_make_progress(ppd);
1380 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1381 } while (!list_empty(pktlist));
1382
1383 return 0;
1384 }
1385
qib_user_sdma_writev(struct qib_ctxtdata * rcd,struct qib_user_sdma_queue * pq,const struct iovec * iov,unsigned long dim)1386 int qib_user_sdma_writev(struct qib_ctxtdata *rcd,
1387 struct qib_user_sdma_queue *pq,
1388 const struct iovec *iov,
1389 unsigned long dim)
1390 {
1391 struct qib_devdata *dd = rcd->dd;
1392 struct qib_pportdata *ppd = rcd->ppd;
1393 int ret = 0;
1394 struct list_head list;
1395 int npkts = 0;
1396
1397 INIT_LIST_HEAD(&list);
1398
1399 mutex_lock(&pq->lock);
1400
1401 /* why not -ECOMM like qib_user_sdma_push_pkts() below? */
1402 if (!qib_sdma_running(ppd))
1403 goto done_unlock;
1404
1405 /* if I have packets not complete yet */
1406 if (pq->added > ppd->sdma_descq_removed)
1407 qib_user_sdma_hwqueue_clean(ppd);
1408 /* if I have complete packets to be freed */
1409 if (pq->num_sending)
1410 qib_user_sdma_queue_clean(ppd, pq);
1411
1412 while (dim) {
1413 int mxp = 1;
1414 int ndesc = 0;
1415
1416 ret = qib_user_sdma_queue_pkts(dd, ppd, pq,
1417 iov, dim, &list, &mxp, &ndesc);
1418 if (ret < 0)
1419 goto done_unlock;
1420 else {
1421 dim -= ret;
1422 iov += ret;
1423 }
1424
1425 /* force packets onto the sdma hw queue... */
1426 if (!list_empty(&list)) {
1427 /*
1428 * Lazily clean hw queue.
1429 */
1430 if (qib_sdma_descq_freecnt(ppd) < ndesc) {
1431 qib_user_sdma_hwqueue_clean(ppd);
1432 if (pq->num_sending)
1433 qib_user_sdma_queue_clean(ppd, pq);
1434 }
1435
1436 ret = qib_user_sdma_push_pkts(ppd, pq, &list, mxp);
1437 if (ret < 0)
1438 goto done_unlock;
1439 else {
1440 npkts += mxp;
1441 pq->counter += mxp;
1442 }
1443 }
1444 }
1445
1446 done_unlock:
1447 if (!list_empty(&list))
1448 qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &list);
1449 mutex_unlock(&pq->lock);
1450
1451 return (ret < 0) ? ret : npkts;
1452 }
1453
qib_user_sdma_make_progress(struct qib_pportdata * ppd,struct qib_user_sdma_queue * pq)1454 int qib_user_sdma_make_progress(struct qib_pportdata *ppd,
1455 struct qib_user_sdma_queue *pq)
1456 {
1457 int ret = 0;
1458
1459 mutex_lock(&pq->lock);
1460 qib_user_sdma_hwqueue_clean(ppd);
1461 ret = qib_user_sdma_queue_clean(ppd, pq);
1462 mutex_unlock(&pq->lock);
1463
1464 return ret;
1465 }
1466
qib_user_sdma_complete_counter(const struct qib_user_sdma_queue * pq)1467 u32 qib_user_sdma_complete_counter(const struct qib_user_sdma_queue *pq)
1468 {
1469 return pq ? pq->sent_counter : 0;
1470 }
1471
qib_user_sdma_inflight_counter(struct qib_user_sdma_queue * pq)1472 u32 qib_user_sdma_inflight_counter(struct qib_user_sdma_queue *pq)
1473 {
1474 return pq ? pq->counter : 0;
1475 }
1476