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 __free_page(page);
324 }
325 ret = -ENOMEM;
326 goto done;
327 }
328 offset = 0;
329 dma_mapped = 1;
330
331
332 next_fragment:
333
334 /*
335 * In tid-sdma, the transfer length is restricted by
336 * receiver side current tid page length.
337 */
338 if (pkt->tiddma && len > pkt->tidsm[pkt->tidsmidx].length)
339 newlen = pkt->tidsm[pkt->tidsmidx].length;
340 else
341 newlen = len;
342
343 /*
344 * Then the transfer length is restricted by MTU.
345 * the last descriptor flag is determined by:
346 * 1. the current packet is at frag size length.
347 * 2. the current tid page is done if tid-sdma.
348 * 3. there is no more byte togo if sdma.
349 */
350 lastdesc = 0;
351 if ((pkt->payload_size + newlen) >= pkt->frag_size) {
352 newlen = pkt->frag_size - pkt->payload_size;
353 lastdesc = 1;
354 } else if (pkt->tiddma) {
355 if (newlen == pkt->tidsm[pkt->tidsmidx].length)
356 lastdesc = 1;
357 } else {
358 if (newlen == pkt->bytes_togo)
359 lastdesc = 1;
360 }
361
362 /* fill the next fragment in this page */
363 qib_user_sdma_init_frag(pkt, pkt->naddr, /* index */
364 offset, newlen, /* offset, len */
365 0, lastdesc, /* first last desc */
366 put, dma_mapped, /* put page, dma mapped */
367 page, kvaddr, /* struct page, virt addr */
368 dma_addr, len); /* dma addr, dma length */
369 pkt->bytes_togo -= newlen;
370 pkt->payload_size += newlen;
371 pkt->naddr++;
372 if (pkt->naddr == pkt->addrlimit) {
373 ret = -EFAULT;
374 goto done;
375 }
376
377 /* If there is no more byte togo. (lastdesc==1) */
378 if (pkt->bytes_togo == 0) {
379 /* The packet is done, header is not dma mapped yet.
380 * it should be from kmalloc */
381 if (!pkt->addr[pkt->index].addr) {
382 pkt->addr[pkt->index].addr =
383 dma_map_single(&dd->pcidev->dev,
384 pkt->addr[pkt->index].kvaddr,
385 pkt->addr[pkt->index].dma_length,
386 DMA_TO_DEVICE);
387 if (dma_mapping_error(&dd->pcidev->dev,
388 pkt->addr[pkt->index].addr)) {
389 ret = -ENOMEM;
390 goto done;
391 }
392 pkt->addr[pkt->index].dma_mapped = 1;
393 }
394
395 goto done;
396 }
397
398 /* If tid-sdma, advance tid info. */
399 if (pkt->tiddma) {
400 pkt->tidsm[pkt->tidsmidx].length -= newlen;
401 if (pkt->tidsm[pkt->tidsmidx].length) {
402 pkt->tidsm[pkt->tidsmidx].offset += newlen;
403 } else {
404 pkt->tidsmidx++;
405 if (pkt->tidsmidx == pkt->tidsmcount) {
406 ret = -EFAULT;
407 goto done;
408 }
409 }
410 }
411
412 /*
413 * If this is NOT the last descriptor. (newlen==len)
414 * the current packet is not done yet, but the current
415 * send side page is done.
416 */
417 if (lastdesc == 0)
418 goto done;
419
420 /*
421 * If running this driver under PSM with message size
422 * fitting into one transfer unit, it is not possible
423 * to pass this line. otherwise, it is a buggggg.
424 */
425
426 /*
427 * Since the current packet is done, and there are more
428 * bytes togo, we need to create a new sdma header, copying
429 * from previous sdma header and modify both.
430 */
431 pbclen = pkt->addr[pkt->index].length;
432 pbcvaddr = qib_user_sdma_alloc_header(pq, pbclen, &pbcdaddr);
433 if (!pbcvaddr) {
434 ret = -ENOMEM;
435 goto done;
436 }
437 /* Copy the previous sdma header to new sdma header */
438 pbc16 = (__le16 *)pkt->addr[pkt->index].kvaddr;
439 memcpy(pbcvaddr, pbc16, pbclen);
440
441 /* Modify the previous sdma header */
442 hdr = (struct qib_message_header *)&pbc16[4];
443
444 /* New pbc length */
445 pbc16[0] = cpu_to_le16(le16_to_cpu(pbc16[0])-(pkt->bytes_togo>>2));
446
447 /* New packet length */
448 hdr->lrh[2] = cpu_to_be16(le16_to_cpu(pbc16[0]));
449
450 if (pkt->tiddma) {
451 /* turn on the header suppression */
452 hdr->iph.pkt_flags =
453 cpu_to_le16(le16_to_cpu(hdr->iph.pkt_flags)|0x2);
454 /* turn off ACK_REQ: 0x04 and EXPECTED_DONE: 0x20 */
455 hdr->flags &= ~(0x04|0x20);
456 } else {
457 /* turn off extra bytes: 20-21 bits */
458 hdr->bth[0] = cpu_to_be32(be32_to_cpu(hdr->bth[0])&0xFFCFFFFF);
459 /* turn off ACK_REQ: 0x04 */
460 hdr->flags &= ~(0x04);
461 }
462
463 /* New kdeth checksum */
464 vcto = le32_to_cpu(hdr->iph.ver_ctxt_tid_offset);
465 hdr->iph.chksum = cpu_to_le16(QIB_LRH_BTH +
466 be16_to_cpu(hdr->lrh[2]) -
467 ((vcto>>16)&0xFFFF) - (vcto&0xFFFF) -
468 le16_to_cpu(hdr->iph.pkt_flags));
469
470 /* The packet is done, header is not dma mapped yet.
471 * it should be from kmalloc */
472 if (!pkt->addr[pkt->index].addr) {
473 pkt->addr[pkt->index].addr =
474 dma_map_single(&dd->pcidev->dev,
475 pkt->addr[pkt->index].kvaddr,
476 pkt->addr[pkt->index].dma_length,
477 DMA_TO_DEVICE);
478 if (dma_mapping_error(&dd->pcidev->dev,
479 pkt->addr[pkt->index].addr)) {
480 ret = -ENOMEM;
481 goto done;
482 }
483 pkt->addr[pkt->index].dma_mapped = 1;
484 }
485
486 /* Modify the new sdma header */
487 pbc16 = (__le16 *)pbcvaddr;
488 hdr = (struct qib_message_header *)&pbc16[4];
489
490 /* New pbc length */
491 pbc16[0] = cpu_to_le16(le16_to_cpu(pbc16[0])-(pkt->payload_size>>2));
492
493 /* New packet length */
494 hdr->lrh[2] = cpu_to_be16(le16_to_cpu(pbc16[0]));
495
496 if (pkt->tiddma) {
497 /* Set new tid and offset for new sdma header */
498 hdr->iph.ver_ctxt_tid_offset = cpu_to_le32(
499 (le32_to_cpu(hdr->iph.ver_ctxt_tid_offset)&0xFF000000) +
500 (pkt->tidsm[pkt->tidsmidx].tid<<QLOGIC_IB_I_TID_SHIFT) +
501 (pkt->tidsm[pkt->tidsmidx].offset>>2));
502 } else {
503 /* Middle protocol new packet offset */
504 hdr->uwords[2] += pkt->payload_size;
505 }
506
507 /* New kdeth checksum */
508 vcto = le32_to_cpu(hdr->iph.ver_ctxt_tid_offset);
509 hdr->iph.chksum = cpu_to_le16(QIB_LRH_BTH +
510 be16_to_cpu(hdr->lrh[2]) -
511 ((vcto>>16)&0xFFFF) - (vcto&0xFFFF) -
512 le16_to_cpu(hdr->iph.pkt_flags));
513
514 /* Next sequence number in new sdma header */
515 seqnum.val = be32_to_cpu(hdr->bth[2]);
516 if (pkt->tiddma)
517 seqnum.seq++;
518 else
519 seqnum.pkt++;
520 hdr->bth[2] = cpu_to_be32(seqnum.val);
521
522 /* Init new sdma header. */
523 qib_user_sdma_init_frag(pkt, pkt->naddr, /* index */
524 0, pbclen, /* offset, len */
525 1, 0, /* first last desc */
526 0, 0, /* put page, dma mapped */
527 NULL, pbcvaddr, /* struct page, virt addr */
528 pbcdaddr, pbclen); /* dma addr, dma length */
529 pkt->index = pkt->naddr;
530 pkt->payload_size = 0;
531 pkt->naddr++;
532 if (pkt->naddr == pkt->addrlimit) {
533 ret = -EFAULT;
534 goto done;
535 }
536
537 /* Prepare for next fragment in this page */
538 if (newlen != len) {
539 if (dma_mapped) {
540 put = 0;
541 dma_mapped = 0;
542 page = NULL;
543 kvaddr = NULL;
544 }
545 len -= newlen;
546 offset += newlen;
547
548 goto next_fragment;
549 }
550
551 done:
552 return ret;
553 }
554
555 /* 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)556 static int qib_user_sdma_coalesce(const struct qib_devdata *dd,
557 struct qib_user_sdma_queue *pq,
558 struct qib_user_sdma_pkt *pkt,
559 const struct iovec *iov,
560 unsigned long niov)
561 {
562 int ret = 0;
563 struct page *page = alloc_page(GFP_KERNEL);
564 void *mpage_save;
565 char *mpage;
566 int i;
567 int len = 0;
568
569 if (!page) {
570 ret = -ENOMEM;
571 goto done;
572 }
573
574 mpage = page_address(page);
575 mpage_save = mpage;
576 for (i = 0; i < niov; i++) {
577 int cfur;
578
579 cfur = copy_from_user(mpage,
580 iov[i].iov_base, iov[i].iov_len);
581 if (cfur) {
582 ret = -EFAULT;
583 goto page_free;
584 }
585
586 mpage += iov[i].iov_len;
587 len += iov[i].iov_len;
588 }
589
590 ret = qib_user_sdma_page_to_frags(dd, pq, pkt,
591 page, 0, 0, len, mpage_save);
592 goto done;
593
594 page_free:
595 __free_page(page);
596 done:
597 return ret;
598 }
599
600 /*
601 * How many pages in this iovec element?
602 */
qib_user_sdma_num_pages(const struct iovec * iov)603 static size_t qib_user_sdma_num_pages(const struct iovec *iov)
604 {
605 const unsigned long addr = (unsigned long) iov->iov_base;
606 const unsigned long len = iov->iov_len;
607 const unsigned long spage = addr & PAGE_MASK;
608 const unsigned long epage = (addr + len - 1) & PAGE_MASK;
609
610 return 1 + ((epage - spage) >> PAGE_SHIFT);
611 }
612
qib_user_sdma_free_pkt_frag(struct device * dev,struct qib_user_sdma_queue * pq,struct qib_user_sdma_pkt * pkt,int frag)613 static void qib_user_sdma_free_pkt_frag(struct device *dev,
614 struct qib_user_sdma_queue *pq,
615 struct qib_user_sdma_pkt *pkt,
616 int frag)
617 {
618 const int i = frag;
619
620 if (pkt->addr[i].page) {
621 /* only user data has page */
622 if (pkt->addr[i].dma_mapped)
623 dma_unmap_page(dev,
624 pkt->addr[i].addr,
625 pkt->addr[i].dma_length,
626 DMA_TO_DEVICE);
627
628 if (pkt->addr[i].put_page)
629 unpin_user_page(pkt->addr[i].page);
630 else
631 __free_page(pkt->addr[i].page);
632 } else if (pkt->addr[i].kvaddr) {
633 /* for headers */
634 if (pkt->addr[i].dma_mapped) {
635 /* from kmalloc & dma mapped */
636 dma_unmap_single(dev,
637 pkt->addr[i].addr,
638 pkt->addr[i].dma_length,
639 DMA_TO_DEVICE);
640 kfree(pkt->addr[i].kvaddr);
641 } else if (pkt->addr[i].addr) {
642 /* free coherent mem from cache... */
643 dma_pool_free(pq->header_cache,
644 pkt->addr[i].kvaddr, pkt->addr[i].addr);
645 } else {
646 /* from kmalloc but not dma mapped */
647 kfree(pkt->addr[i].kvaddr);
648 }
649 }
650 }
651
652 /* 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)653 static int qib_user_sdma_pin_pages(const struct qib_devdata *dd,
654 struct qib_user_sdma_queue *pq,
655 struct qib_user_sdma_pkt *pkt,
656 unsigned long addr, int tlen, size_t npages)
657 {
658 struct page *pages[8];
659 int i, j;
660 int ret = 0;
661
662 while (npages) {
663 if (npages > 8)
664 j = 8;
665 else
666 j = npages;
667
668 ret = pin_user_pages_fast(addr, j, FOLL_LONGTERM, pages);
669 if (ret != j) {
670 i = 0;
671 j = ret;
672 ret = -ENOMEM;
673 goto free_pages;
674 }
675
676 for (i = 0; i < j; i++) {
677 /* map the pages... */
678 unsigned long fofs = addr & ~PAGE_MASK;
679 int flen = ((fofs + tlen) > PAGE_SIZE) ?
680 (PAGE_SIZE - fofs) : tlen;
681
682 ret = qib_user_sdma_page_to_frags(dd, pq, pkt,
683 pages[i], 1, fofs, flen, NULL);
684 if (ret < 0) {
685 /* current page has beed taken
686 * care of inside above call.
687 */
688 i++;
689 goto free_pages;
690 }
691
692 addr += flen;
693 tlen -= flen;
694 }
695
696 npages -= j;
697 }
698
699 goto done;
700
701 /* if error, return all pages not managed by pkt */
702 free_pages:
703 while (i < j)
704 unpin_user_page(pages[i++]);
705
706 done:
707 return ret;
708 }
709
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)710 static int qib_user_sdma_pin_pkt(const struct qib_devdata *dd,
711 struct qib_user_sdma_queue *pq,
712 struct qib_user_sdma_pkt *pkt,
713 const struct iovec *iov,
714 unsigned long niov)
715 {
716 int ret = 0;
717 unsigned long idx;
718
719 for (idx = 0; idx < niov; idx++) {
720 const size_t npages = qib_user_sdma_num_pages(iov + idx);
721 const unsigned long addr = (unsigned long) iov[idx].iov_base;
722
723 ret = qib_user_sdma_pin_pages(dd, pq, pkt, addr,
724 iov[idx].iov_len, npages);
725 if (ret < 0)
726 goto free_pkt;
727 }
728
729 goto done;
730
731 free_pkt:
732 /* we need to ignore the first entry here */
733 for (idx = 1; idx < pkt->naddr; idx++)
734 qib_user_sdma_free_pkt_frag(&dd->pcidev->dev, pq, pkt, idx);
735
736 /* need to dma unmap the first entry, this is to restore to
737 * the original state so that caller can free the memory in
738 * error condition. Caller does not know if dma mapped or not*/
739 if (pkt->addr[0].dma_mapped) {
740 dma_unmap_single(&dd->pcidev->dev,
741 pkt->addr[0].addr,
742 pkt->addr[0].dma_length,
743 DMA_TO_DEVICE);
744 pkt->addr[0].addr = 0;
745 pkt->addr[0].dma_mapped = 0;
746 }
747
748 done:
749 return ret;
750 }
751
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)752 static int qib_user_sdma_init_payload(const struct qib_devdata *dd,
753 struct qib_user_sdma_queue *pq,
754 struct qib_user_sdma_pkt *pkt,
755 const struct iovec *iov,
756 unsigned long niov, int npages)
757 {
758 int ret = 0;
759
760 if (pkt->frag_size == pkt->bytes_togo &&
761 npages >= ARRAY_SIZE(pkt->addr))
762 ret = qib_user_sdma_coalesce(dd, pq, pkt, iov, niov);
763 else
764 ret = qib_user_sdma_pin_pkt(dd, pq, pkt, iov, niov);
765
766 return ret;
767 }
768
769 /* 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)770 static void qib_user_sdma_free_pkt_list(struct device *dev,
771 struct qib_user_sdma_queue *pq,
772 struct list_head *list)
773 {
774 struct qib_user_sdma_pkt *pkt, *pkt_next;
775
776 list_for_each_entry_safe(pkt, pkt_next, list, list) {
777 int i;
778
779 for (i = 0; i < pkt->naddr; i++)
780 qib_user_sdma_free_pkt_frag(dev, pq, pkt, i);
781
782 if (pkt->largepkt)
783 kfree(pkt);
784 else
785 kmem_cache_free(pq->pkt_slab, pkt);
786 }
787 INIT_LIST_HEAD(list);
788 }
789
790 /*
791 * copy headers, coalesce etc -- pq->lock must be held
792 *
793 * we queue all the packets to list, returning the
794 * number of bytes total. list must be empty initially,
795 * as, if there is an error we clean it...
796 */
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)797 static int qib_user_sdma_queue_pkts(const struct qib_devdata *dd,
798 struct qib_pportdata *ppd,
799 struct qib_user_sdma_queue *pq,
800 const struct iovec *iov,
801 unsigned long niov,
802 struct list_head *list,
803 int *maxpkts, int *ndesc)
804 {
805 unsigned long idx = 0;
806 int ret = 0;
807 int npkts = 0;
808 __le32 *pbc;
809 dma_addr_t dma_addr;
810 struct qib_user_sdma_pkt *pkt = NULL;
811 size_t len;
812 size_t nw;
813 u32 counter = pq->counter;
814 u16 frag_size;
815
816 while (idx < niov && npkts < *maxpkts) {
817 const unsigned long addr = (unsigned long) iov[idx].iov_base;
818 const unsigned long idx_save = idx;
819 unsigned pktnw;
820 unsigned pktnwc;
821 int nfrags = 0;
822 size_t npages = 0;
823 size_t bytes_togo = 0;
824 int tiddma = 0;
825 int cfur;
826
827 len = iov[idx].iov_len;
828 nw = len >> 2;
829
830 if (len < QIB_USER_SDMA_MIN_HEADER_LENGTH ||
831 len > PAGE_SIZE || len & 3 || addr & 3) {
832 ret = -EINVAL;
833 goto free_list;
834 }
835
836 pbc = qib_user_sdma_alloc_header(pq, len, &dma_addr);
837 if (!pbc) {
838 ret = -ENOMEM;
839 goto free_list;
840 }
841
842 cfur = copy_from_user(pbc, iov[idx].iov_base, len);
843 if (cfur) {
844 ret = -EFAULT;
845 goto free_pbc;
846 }
847
848 /*
849 * This assignment is a bit strange. it's because
850 * the pbc counts the number of 32 bit words in the full
851 * packet _except_ the first word of the pbc itself...
852 */
853 pktnwc = nw - 1;
854
855 /*
856 * pktnw computation yields the number of 32 bit words
857 * that the caller has indicated in the PBC. note that
858 * this is one less than the total number of words that
859 * goes to the send DMA engine as the first 32 bit word
860 * of the PBC itself is not counted. Armed with this count,
861 * we can verify that the packet is consistent with the
862 * iovec lengths.
863 */
864 pktnw = le32_to_cpu(*pbc) & 0xFFFF;
865 if (pktnw < pktnwc) {
866 ret = -EINVAL;
867 goto free_pbc;
868 }
869
870 idx++;
871 while (pktnwc < pktnw && idx < niov) {
872 const size_t slen = iov[idx].iov_len;
873 const unsigned long faddr =
874 (unsigned long) iov[idx].iov_base;
875
876 if (slen & 3 || faddr & 3 || !slen) {
877 ret = -EINVAL;
878 goto free_pbc;
879 }
880
881 npages += qib_user_sdma_num_pages(&iov[idx]);
882
883 if (check_add_overflow(bytes_togo, slen, &bytes_togo) ||
884 bytes_togo > type_max(typeof(pkt->bytes_togo))) {
885 ret = -EINVAL;
886 goto free_pbc;
887 }
888 pktnwc += slen >> 2;
889 idx++;
890 nfrags++;
891 }
892
893 if (pktnwc != pktnw) {
894 ret = -EINVAL;
895 goto free_pbc;
896 }
897
898 frag_size = ((le32_to_cpu(*pbc))>>16) & 0xFFFF;
899 if (((frag_size ? frag_size : bytes_togo) + len) >
900 ppd->ibmaxlen) {
901 ret = -EINVAL;
902 goto free_pbc;
903 }
904
905 if (frag_size) {
906 size_t tidsmsize, n, pktsize, sz, addrlimit;
907
908 n = npages*((2*PAGE_SIZE/frag_size)+1);
909 pktsize = struct_size(pkt, addr, n);
910
911 /*
912 * Determine if this is tid-sdma or just sdma.
913 */
914 tiddma = (((le32_to_cpu(pbc[7])>>
915 QLOGIC_IB_I_TID_SHIFT)&
916 QLOGIC_IB_I_TID_MASK) !=
917 QLOGIC_IB_I_TID_MASK);
918
919 if (tiddma)
920 tidsmsize = iov[idx].iov_len;
921 else
922 tidsmsize = 0;
923
924 if (check_add_overflow(pktsize, tidsmsize, &sz)) {
925 ret = -EINVAL;
926 goto free_pbc;
927 }
928 pkt = kmalloc(sz, GFP_KERNEL);
929 if (!pkt) {
930 ret = -ENOMEM;
931 goto free_pbc;
932 }
933 pkt->largepkt = 1;
934 pkt->frag_size = frag_size;
935 if (check_add_overflow(n, ARRAY_SIZE(pkt->addr),
936 &addrlimit) ||
937 addrlimit > type_max(typeof(pkt->addrlimit))) {
938 ret = -EINVAL;
939 goto free_pkt;
940 }
941 pkt->addrlimit = addrlimit;
942
943 if (tiddma) {
944 char *tidsm = (char *)pkt + pktsize;
945
946 cfur = copy_from_user(tidsm,
947 iov[idx].iov_base, tidsmsize);
948 if (cfur) {
949 ret = -EFAULT;
950 goto free_pkt;
951 }
952 pkt->tidsm =
953 (struct qib_tid_session_member *)tidsm;
954 pkt->tidsmcount = tidsmsize/
955 sizeof(struct qib_tid_session_member);
956 pkt->tidsmidx = 0;
957 idx++;
958 }
959
960 /*
961 * pbc 'fill1' field is borrowed to pass frag size,
962 * we need to clear it after picking frag size, the
963 * hardware requires this field to be zero.
964 */
965 *pbc = cpu_to_le32(le32_to_cpu(*pbc) & 0x0000FFFF);
966 } else {
967 pkt = kmem_cache_alloc(pq->pkt_slab, GFP_KERNEL);
968 if (!pkt) {
969 ret = -ENOMEM;
970 goto free_pbc;
971 }
972 pkt->largepkt = 0;
973 pkt->frag_size = bytes_togo;
974 pkt->addrlimit = ARRAY_SIZE(pkt->addr);
975 }
976 pkt->bytes_togo = bytes_togo;
977 pkt->payload_size = 0;
978 pkt->counter = counter;
979 pkt->tiddma = tiddma;
980
981 /* setup the first header */
982 qib_user_sdma_init_frag(pkt, 0, /* index */
983 0, len, /* offset, len */
984 1, 0, /* first last desc */
985 0, 0, /* put page, dma mapped */
986 NULL, pbc, /* struct page, virt addr */
987 dma_addr, len); /* dma addr, dma length */
988 pkt->index = 0;
989 pkt->naddr = 1;
990
991 if (nfrags) {
992 ret = qib_user_sdma_init_payload(dd, pq, pkt,
993 iov + idx_save + 1,
994 nfrags, npages);
995 if (ret < 0)
996 goto free_pkt;
997 } else {
998 /* since there is no payload, mark the
999 * header as the last desc. */
1000 pkt->addr[0].last_desc = 1;
1001
1002 if (dma_addr == 0) {
1003 /*
1004 * the header is not dma mapped yet.
1005 * it should be from kmalloc.
1006 */
1007 dma_addr = dma_map_single(&dd->pcidev->dev,
1008 pbc, len, DMA_TO_DEVICE);
1009 if (dma_mapping_error(&dd->pcidev->dev,
1010 dma_addr)) {
1011 ret = -ENOMEM;
1012 goto free_pkt;
1013 }
1014 pkt->addr[0].addr = dma_addr;
1015 pkt->addr[0].dma_mapped = 1;
1016 }
1017 }
1018
1019 counter++;
1020 npkts++;
1021 pkt->pq = pq;
1022 pkt->index = 0; /* reset index for push on hw */
1023 *ndesc += pkt->naddr;
1024
1025 list_add_tail(&pkt->list, list);
1026 }
1027
1028 *maxpkts = npkts;
1029 ret = idx;
1030 goto done;
1031
1032 free_pkt:
1033 if (pkt->largepkt)
1034 kfree(pkt);
1035 else
1036 kmem_cache_free(pq->pkt_slab, pkt);
1037 free_pbc:
1038 if (dma_addr)
1039 dma_pool_free(pq->header_cache, pbc, dma_addr);
1040 else
1041 kfree(pbc);
1042 free_list:
1043 qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, list);
1044 done:
1045 return ret;
1046 }
1047
qib_user_sdma_set_complete_counter(struct qib_user_sdma_queue * pq,u32 c)1048 static void qib_user_sdma_set_complete_counter(struct qib_user_sdma_queue *pq,
1049 u32 c)
1050 {
1051 pq->sent_counter = c;
1052 }
1053
1054 /* try to clean out queue -- needs pq->lock */
qib_user_sdma_queue_clean(struct qib_pportdata * ppd,struct qib_user_sdma_queue * pq)1055 static int qib_user_sdma_queue_clean(struct qib_pportdata *ppd,
1056 struct qib_user_sdma_queue *pq)
1057 {
1058 struct qib_devdata *dd = ppd->dd;
1059 struct list_head free_list;
1060 struct qib_user_sdma_pkt *pkt;
1061 struct qib_user_sdma_pkt *pkt_prev;
1062 unsigned long flags;
1063 int ret = 0;
1064
1065 if (!pq->num_sending)
1066 return 0;
1067
1068 INIT_LIST_HEAD(&free_list);
1069
1070 /*
1071 * We need this spin lock here because interrupt handler
1072 * might modify this list in qib_user_sdma_send_desc(), also
1073 * we can not get interrupted, otherwise it is a deadlock.
1074 */
1075 spin_lock_irqsave(&pq->sent_lock, flags);
1076 list_for_each_entry_safe(pkt, pkt_prev, &pq->sent, list) {
1077 s64 descd = ppd->sdma_descq_removed - pkt->added;
1078
1079 if (descd < 0)
1080 break;
1081
1082 list_move_tail(&pkt->list, &free_list);
1083
1084 /* one more packet cleaned */
1085 ret++;
1086 pq->num_sending--;
1087 }
1088 spin_unlock_irqrestore(&pq->sent_lock, flags);
1089
1090 if (!list_empty(&free_list)) {
1091 u32 counter;
1092
1093 pkt = list_entry(free_list.prev,
1094 struct qib_user_sdma_pkt, list);
1095 counter = pkt->counter;
1096
1097 qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &free_list);
1098 qib_user_sdma_set_complete_counter(pq, counter);
1099 }
1100
1101 return ret;
1102 }
1103
qib_user_sdma_queue_destroy(struct qib_user_sdma_queue * pq)1104 void qib_user_sdma_queue_destroy(struct qib_user_sdma_queue *pq)
1105 {
1106 if (!pq)
1107 return;
1108
1109 pq->sdma_rb_node->refcount--;
1110 if (pq->sdma_rb_node->refcount == 0) {
1111 rb_erase(&pq->sdma_rb_node->node, &qib_user_sdma_rb_root);
1112 kfree(pq->sdma_rb_node);
1113 }
1114 dma_pool_destroy(pq->header_cache);
1115 kmem_cache_destroy(pq->pkt_slab);
1116 kfree(pq);
1117 }
1118
1119 /* clean descriptor queue, returns > 0 if some elements cleaned */
qib_user_sdma_hwqueue_clean(struct qib_pportdata * ppd)1120 static int qib_user_sdma_hwqueue_clean(struct qib_pportdata *ppd)
1121 {
1122 int ret;
1123 unsigned long flags;
1124
1125 spin_lock_irqsave(&ppd->sdma_lock, flags);
1126 ret = qib_sdma_make_progress(ppd);
1127 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1128
1129 return ret;
1130 }
1131
1132 /* 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)1133 void qib_user_sdma_queue_drain(struct qib_pportdata *ppd,
1134 struct qib_user_sdma_queue *pq)
1135 {
1136 struct qib_devdata *dd = ppd->dd;
1137 unsigned long flags;
1138 int i;
1139
1140 if (!pq)
1141 return;
1142
1143 for (i = 0; i < QIB_USER_SDMA_DRAIN_TIMEOUT; i++) {
1144 mutex_lock(&pq->lock);
1145 if (!pq->num_pending && !pq->num_sending) {
1146 mutex_unlock(&pq->lock);
1147 break;
1148 }
1149 qib_user_sdma_hwqueue_clean(ppd);
1150 qib_user_sdma_queue_clean(ppd, pq);
1151 mutex_unlock(&pq->lock);
1152 msleep(20);
1153 }
1154
1155 if (pq->num_pending || pq->num_sending) {
1156 struct qib_user_sdma_pkt *pkt;
1157 struct qib_user_sdma_pkt *pkt_prev;
1158 struct list_head free_list;
1159
1160 mutex_lock(&pq->lock);
1161 spin_lock_irqsave(&ppd->sdma_lock, flags);
1162 /*
1163 * Since we hold sdma_lock, it is safe without sent_lock.
1164 */
1165 if (pq->num_pending) {
1166 list_for_each_entry_safe(pkt, pkt_prev,
1167 &ppd->sdma_userpending, list) {
1168 if (pkt->pq == pq) {
1169 list_move_tail(&pkt->list, &pq->sent);
1170 pq->num_pending--;
1171 pq->num_sending++;
1172 }
1173 }
1174 }
1175 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1176
1177 qib_dev_err(dd, "user sdma lists not empty: forcing!\n");
1178 INIT_LIST_HEAD(&free_list);
1179 list_splice_init(&pq->sent, &free_list);
1180 pq->num_sending = 0;
1181 qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &free_list);
1182 mutex_unlock(&pq->lock);
1183 }
1184 }
1185
qib_sdma_make_desc0(u8 gen,u64 addr,u64 dwlen,u64 dwoffset)1186 static inline __le64 qib_sdma_make_desc0(u8 gen,
1187 u64 addr, u64 dwlen, u64 dwoffset)
1188 {
1189 return cpu_to_le64(/* SDmaPhyAddr[31:0] */
1190 ((addr & 0xfffffffcULL) << 32) |
1191 /* SDmaGeneration[1:0] */
1192 ((gen & 3ULL) << 30) |
1193 /* SDmaDwordCount[10:0] */
1194 ((dwlen & 0x7ffULL) << 16) |
1195 /* SDmaBufOffset[12:2] */
1196 (dwoffset & 0x7ffULL));
1197 }
1198
qib_sdma_make_first_desc0(__le64 descq)1199 static inline __le64 qib_sdma_make_first_desc0(__le64 descq)
1200 {
1201 return descq | cpu_to_le64(1ULL << 12);
1202 }
1203
qib_sdma_make_last_desc0(__le64 descq)1204 static inline __le64 qib_sdma_make_last_desc0(__le64 descq)
1205 {
1206 /* last */ /* dma head */
1207 return descq | cpu_to_le64(1ULL << 11 | 1ULL << 13);
1208 }
1209
qib_sdma_make_desc1(u64 addr)1210 static inline __le64 qib_sdma_make_desc1(u64 addr)
1211 {
1212 /* SDmaPhyAddr[47:32] */
1213 return cpu_to_le64(addr >> 32);
1214 }
1215
qib_user_sdma_send_frag(struct qib_pportdata * ppd,struct qib_user_sdma_pkt * pkt,int idx,unsigned ofs,u16 tail,u8 gen)1216 static void qib_user_sdma_send_frag(struct qib_pportdata *ppd,
1217 struct qib_user_sdma_pkt *pkt, int idx,
1218 unsigned ofs, u16 tail, u8 gen)
1219 {
1220 const u64 addr = (u64) pkt->addr[idx].addr +
1221 (u64) pkt->addr[idx].offset;
1222 const u64 dwlen = (u64) pkt->addr[idx].length / 4;
1223 __le64 *descqp;
1224 __le64 descq0;
1225
1226 descqp = &ppd->sdma_descq[tail].qw[0];
1227
1228 descq0 = qib_sdma_make_desc0(gen, addr, dwlen, ofs);
1229 if (pkt->addr[idx].first_desc)
1230 descq0 = qib_sdma_make_first_desc0(descq0);
1231 if (pkt->addr[idx].last_desc) {
1232 descq0 = qib_sdma_make_last_desc0(descq0);
1233 if (ppd->sdma_intrequest) {
1234 descq0 |= cpu_to_le64(1ULL << 15);
1235 ppd->sdma_intrequest = 0;
1236 }
1237 }
1238
1239 descqp[0] = descq0;
1240 descqp[1] = qib_sdma_make_desc1(addr);
1241 }
1242
qib_user_sdma_send_desc(struct qib_pportdata * ppd,struct list_head * pktlist)1243 void qib_user_sdma_send_desc(struct qib_pportdata *ppd,
1244 struct list_head *pktlist)
1245 {
1246 struct qib_devdata *dd = ppd->dd;
1247 u16 nfree, nsent;
1248 u16 tail, tail_c;
1249 u8 gen, gen_c;
1250
1251 nfree = qib_sdma_descq_freecnt(ppd);
1252 if (!nfree)
1253 return;
1254
1255 retry:
1256 nsent = 0;
1257 tail_c = tail = ppd->sdma_descq_tail;
1258 gen_c = gen = ppd->sdma_generation;
1259 while (!list_empty(pktlist)) {
1260 struct qib_user_sdma_pkt *pkt =
1261 list_entry(pktlist->next, struct qib_user_sdma_pkt,
1262 list);
1263 int i, j, c = 0;
1264 unsigned ofs = 0;
1265 u16 dtail = tail;
1266
1267 for (i = pkt->index; i < pkt->naddr && nfree; i++) {
1268 qib_user_sdma_send_frag(ppd, pkt, i, ofs, tail, gen);
1269 ofs += pkt->addr[i].length >> 2;
1270
1271 if (++tail == ppd->sdma_descq_cnt) {
1272 tail = 0;
1273 ++gen;
1274 ppd->sdma_intrequest = 1;
1275 } else if (tail == (ppd->sdma_descq_cnt>>1)) {
1276 ppd->sdma_intrequest = 1;
1277 }
1278 nfree--;
1279 if (pkt->addr[i].last_desc == 0)
1280 continue;
1281
1282 /*
1283 * If the packet is >= 2KB mtu equivalent, we
1284 * have to use the large buffers, and have to
1285 * mark each descriptor as part of a large
1286 * buffer packet.
1287 */
1288 if (ofs > dd->piosize2kmax_dwords) {
1289 for (j = pkt->index; j <= i; j++) {
1290 ppd->sdma_descq[dtail].qw[0] |=
1291 cpu_to_le64(1ULL << 14);
1292 if (++dtail == ppd->sdma_descq_cnt)
1293 dtail = 0;
1294 }
1295 }
1296 c += i + 1 - pkt->index;
1297 pkt->index = i + 1; /* index for next first */
1298 tail_c = dtail = tail;
1299 gen_c = gen;
1300 ofs = 0; /* reset for next packet */
1301 }
1302
1303 ppd->sdma_descq_added += c;
1304 nsent += c;
1305 if (pkt->index == pkt->naddr) {
1306 pkt->added = ppd->sdma_descq_added;
1307 pkt->pq->added = pkt->added;
1308 pkt->pq->num_pending--;
1309 spin_lock(&pkt->pq->sent_lock);
1310 pkt->pq->num_sending++;
1311 list_move_tail(&pkt->list, &pkt->pq->sent);
1312 spin_unlock(&pkt->pq->sent_lock);
1313 }
1314 if (!nfree || (nsent<<2) > ppd->sdma_descq_cnt)
1315 break;
1316 }
1317
1318 /* advance the tail on the chip if necessary */
1319 if (ppd->sdma_descq_tail != tail_c) {
1320 ppd->sdma_generation = gen_c;
1321 dd->f_sdma_update_tail(ppd, tail_c);
1322 }
1323
1324 if (nfree && !list_empty(pktlist))
1325 goto retry;
1326 }
1327
1328 /* 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)1329 static int qib_user_sdma_push_pkts(struct qib_pportdata *ppd,
1330 struct qib_user_sdma_queue *pq,
1331 struct list_head *pktlist, int count)
1332 {
1333 unsigned long flags;
1334
1335 if (unlikely(!(ppd->lflags & QIBL_LINKACTIVE)))
1336 return -ECOMM;
1337
1338 /* non-blocking mode */
1339 if (pq->sdma_rb_node->refcount > 1) {
1340 spin_lock_irqsave(&ppd->sdma_lock, flags);
1341 if (unlikely(!__qib_sdma_running(ppd))) {
1342 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1343 return -ECOMM;
1344 }
1345 pq->num_pending += count;
1346 list_splice_tail_init(pktlist, &ppd->sdma_userpending);
1347 qib_user_sdma_send_desc(ppd, &ppd->sdma_userpending);
1348 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1349 return 0;
1350 }
1351
1352 /* In this case, descriptors from this process are not
1353 * linked to ppd pending queue, interrupt handler
1354 * won't update this process, it is OK to directly
1355 * modify without sdma lock.
1356 */
1357
1358
1359 pq->num_pending += count;
1360 /*
1361 * Blocking mode for single rail process, we must
1362 * release/regain sdma_lock to give other process
1363 * chance to make progress. This is important for
1364 * performance.
1365 */
1366 do {
1367 spin_lock_irqsave(&ppd->sdma_lock, flags);
1368 if (unlikely(!__qib_sdma_running(ppd))) {
1369 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1370 return -ECOMM;
1371 }
1372 qib_user_sdma_send_desc(ppd, pktlist);
1373 if (!list_empty(pktlist))
1374 qib_sdma_make_progress(ppd);
1375 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1376 } while (!list_empty(pktlist));
1377
1378 return 0;
1379 }
1380
qib_user_sdma_writev(struct qib_ctxtdata * rcd,struct qib_user_sdma_queue * pq,const struct iovec * iov,unsigned long dim)1381 int qib_user_sdma_writev(struct qib_ctxtdata *rcd,
1382 struct qib_user_sdma_queue *pq,
1383 const struct iovec *iov,
1384 unsigned long dim)
1385 {
1386 struct qib_devdata *dd = rcd->dd;
1387 struct qib_pportdata *ppd = rcd->ppd;
1388 int ret = 0;
1389 struct list_head list;
1390 int npkts = 0;
1391
1392 INIT_LIST_HEAD(&list);
1393
1394 mutex_lock(&pq->lock);
1395
1396 /* why not -ECOMM like qib_user_sdma_push_pkts() below? */
1397 if (!qib_sdma_running(ppd))
1398 goto done_unlock;
1399
1400 /* if I have packets not complete yet */
1401 if (pq->added > ppd->sdma_descq_removed)
1402 qib_user_sdma_hwqueue_clean(ppd);
1403 /* if I have complete packets to be freed */
1404 if (pq->num_sending)
1405 qib_user_sdma_queue_clean(ppd, pq);
1406
1407 while (dim) {
1408 int mxp = 1;
1409 int ndesc = 0;
1410
1411 ret = qib_user_sdma_queue_pkts(dd, ppd, pq,
1412 iov, dim, &list, &mxp, &ndesc);
1413 if (ret < 0)
1414 goto done_unlock;
1415 else {
1416 dim -= ret;
1417 iov += ret;
1418 }
1419
1420 /* force packets onto the sdma hw queue... */
1421 if (!list_empty(&list)) {
1422 /*
1423 * Lazily clean hw queue.
1424 */
1425 if (qib_sdma_descq_freecnt(ppd) < ndesc) {
1426 qib_user_sdma_hwqueue_clean(ppd);
1427 if (pq->num_sending)
1428 qib_user_sdma_queue_clean(ppd, pq);
1429 }
1430
1431 ret = qib_user_sdma_push_pkts(ppd, pq, &list, mxp);
1432 if (ret < 0)
1433 goto done_unlock;
1434 else {
1435 npkts += mxp;
1436 pq->counter += mxp;
1437 }
1438 }
1439 }
1440
1441 done_unlock:
1442 if (!list_empty(&list))
1443 qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &list);
1444 mutex_unlock(&pq->lock);
1445
1446 return (ret < 0) ? ret : npkts;
1447 }
1448
qib_user_sdma_make_progress(struct qib_pportdata * ppd,struct qib_user_sdma_queue * pq)1449 int qib_user_sdma_make_progress(struct qib_pportdata *ppd,
1450 struct qib_user_sdma_queue *pq)
1451 {
1452 int ret = 0;
1453
1454 mutex_lock(&pq->lock);
1455 qib_user_sdma_hwqueue_clean(ppd);
1456 ret = qib_user_sdma_queue_clean(ppd, pq);
1457 mutex_unlock(&pq->lock);
1458
1459 return ret;
1460 }
1461
qib_user_sdma_complete_counter(const struct qib_user_sdma_queue * pq)1462 u32 qib_user_sdma_complete_counter(const struct qib_user_sdma_queue *pq)
1463 {
1464 return pq ? pq->sent_counter : 0;
1465 }
1466
qib_user_sdma_inflight_counter(struct qib_user_sdma_queue * pq)1467 u32 qib_user_sdma_inflight_counter(struct qib_user_sdma_queue *pq)
1468 {
1469 return pq ? pq->counter : 0;
1470 }
1471