Merge tag 'v3.3.7' into 3.3/master
[zen-stable.git] / drivers / infiniband / hw / ipath / ipath_user_sdma.c
blobf5cb13b2144566229c03be75e31623cb19942d45
1 /*
2 * Copyright (c) 2007, 2008 QLogic Corporation. All rights reserved.
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:
10 * Redistribution and use in source and binary forms, with or
11 * without modification, are permitted provided that the following
12 * conditions are met:
14 * - Redistributions of source code must retain the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer.
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.
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.
32 #include <linux/mm.h>
33 #include <linux/types.h>
34 #include <linux/device.h>
35 #include <linux/dmapool.h>
36 #include <linux/sched.h>
37 #include <linux/slab.h>
38 #include <linux/list.h>
39 #include <linux/highmem.h>
40 #include <linux/io.h>
41 #include <linux/uio.h>
42 #include <linux/rbtree.h>
43 #include <linux/spinlock.h>
44 #include <linux/delay.h>
46 #include "ipath_kernel.h"
47 #include "ipath_user_sdma.h"
49 /* minimum size of header */
50 #define IPATH_USER_SDMA_MIN_HEADER_LENGTH 64
51 /* expected size of headers (for dma_pool) */
52 #define IPATH_USER_SDMA_EXP_HEADER_LENGTH 64
53 /* length mask in PBC (lower 11 bits) */
54 #define IPATH_PBC_LENGTH_MASK ((1 << 11) - 1)
56 struct ipath_user_sdma_pkt {
57 u8 naddr; /* dimension of addr (1..3) ... */
58 u32 counter; /* sdma pkts queued counter for this entry */
59 u64 added; /* global descq number of entries */
61 struct {
62 u32 offset; /* offset for kvaddr, addr */
63 u32 length; /* length in page */
64 u8 put_page; /* should we put_page? */
65 u8 dma_mapped; /* is page dma_mapped? */
66 struct page *page; /* may be NULL (coherent mem) */
67 void *kvaddr; /* FIXME: only for pio hack */
68 dma_addr_t addr;
69 } addr[4]; /* max pages, any more and we coalesce */
70 struct list_head list; /* list element */
73 struct ipath_user_sdma_queue {
75 * pkts sent to dma engine are queued on this
76 * list head. the type of the elements of this
77 * list are struct ipath_user_sdma_pkt...
79 struct list_head sent;
81 /* headers with expected length are allocated from here... */
82 char header_cache_name[64];
83 struct dma_pool *header_cache;
85 /* packets are allocated from the slab cache... */
86 char pkt_slab_name[64];
87 struct kmem_cache *pkt_slab;
89 /* as packets go on the queued queue, they are counted... */
90 u32 counter;
91 u32 sent_counter;
93 /* dma page table */
94 struct rb_root dma_pages_root;
96 /* protect everything above... */
97 struct mutex lock;
100 struct ipath_user_sdma_queue *
101 ipath_user_sdma_queue_create(struct device *dev, int unit, int port, int sport)
103 struct ipath_user_sdma_queue *pq =
104 kmalloc(sizeof(struct ipath_user_sdma_queue), GFP_KERNEL);
106 if (!pq)
107 goto done;
109 pq->counter = 0;
110 pq->sent_counter = 0;
111 INIT_LIST_HEAD(&pq->sent);
113 mutex_init(&pq->lock);
115 snprintf(pq->pkt_slab_name, sizeof(pq->pkt_slab_name),
116 "ipath-user-sdma-pkts-%u-%02u.%02u", unit, port, sport);
117 pq->pkt_slab = kmem_cache_create(pq->pkt_slab_name,
118 sizeof(struct ipath_user_sdma_pkt),
119 0, 0, NULL);
121 if (!pq->pkt_slab)
122 goto err_kfree;
124 snprintf(pq->header_cache_name, sizeof(pq->header_cache_name),
125 "ipath-user-sdma-headers-%u-%02u.%02u", unit, port, sport);
126 pq->header_cache = dma_pool_create(pq->header_cache_name,
127 dev,
128 IPATH_USER_SDMA_EXP_HEADER_LENGTH,
129 4, 0);
130 if (!pq->header_cache)
131 goto err_slab;
133 pq->dma_pages_root = RB_ROOT;
135 goto done;
137 err_slab:
138 kmem_cache_destroy(pq->pkt_slab);
139 err_kfree:
140 kfree(pq);
141 pq = NULL;
143 done:
144 return pq;
147 static void ipath_user_sdma_init_frag(struct ipath_user_sdma_pkt *pkt,
148 int i, size_t offset, size_t len,
149 int put_page, int dma_mapped,
150 struct page *page,
151 void *kvaddr, dma_addr_t dma_addr)
153 pkt->addr[i].offset = offset;
154 pkt->addr[i].length = len;
155 pkt->addr[i].put_page = put_page;
156 pkt->addr[i].dma_mapped = dma_mapped;
157 pkt->addr[i].page = page;
158 pkt->addr[i].kvaddr = kvaddr;
159 pkt->addr[i].addr = dma_addr;
162 static void ipath_user_sdma_init_header(struct ipath_user_sdma_pkt *pkt,
163 u32 counter, size_t offset,
164 size_t len, int dma_mapped,
165 struct page *page,
166 void *kvaddr, dma_addr_t dma_addr)
168 pkt->naddr = 1;
169 pkt->counter = counter;
170 ipath_user_sdma_init_frag(pkt, 0, offset, len, 0, dma_mapped, page,
171 kvaddr, dma_addr);
174 /* we've too many pages in the iovec, coalesce to a single page */
175 static int ipath_user_sdma_coalesce(const struct ipath_devdata *dd,
176 struct ipath_user_sdma_pkt *pkt,
177 const struct iovec *iov,
178 unsigned long niov) {
179 int ret = 0;
180 struct page *page = alloc_page(GFP_KERNEL);
181 void *mpage_save;
182 char *mpage;
183 int i;
184 int len = 0;
185 dma_addr_t dma_addr;
187 if (!page) {
188 ret = -ENOMEM;
189 goto done;
192 mpage = kmap(page);
193 mpage_save = mpage;
194 for (i = 0; i < niov; i++) {
195 int cfur;
197 cfur = copy_from_user(mpage,
198 iov[i].iov_base, iov[i].iov_len);
199 if (cfur) {
200 ret = -EFAULT;
201 goto free_unmap;
204 mpage += iov[i].iov_len;
205 len += iov[i].iov_len;
208 dma_addr = dma_map_page(&dd->pcidev->dev, page, 0, len,
209 DMA_TO_DEVICE);
210 if (dma_mapping_error(&dd->pcidev->dev, dma_addr)) {
211 ret = -ENOMEM;
212 goto free_unmap;
215 ipath_user_sdma_init_frag(pkt, 1, 0, len, 0, 1, page, mpage_save,
216 dma_addr);
217 pkt->naddr = 2;
219 goto done;
221 free_unmap:
222 kunmap(page);
223 __free_page(page);
224 done:
225 return ret;
228 /* how many pages in this iovec element? */
229 static int ipath_user_sdma_num_pages(const struct iovec *iov)
231 const unsigned long addr = (unsigned long) iov->iov_base;
232 const unsigned long len = iov->iov_len;
233 const unsigned long spage = addr & PAGE_MASK;
234 const unsigned long epage = (addr + len - 1) & PAGE_MASK;
236 return 1 + ((epage - spage) >> PAGE_SHIFT);
239 /* truncate length to page boundary */
240 static int ipath_user_sdma_page_length(unsigned long addr, unsigned long len)
242 const unsigned long offset = addr & ~PAGE_MASK;
244 return ((offset + len) > PAGE_SIZE) ? (PAGE_SIZE - offset) : len;
247 static void ipath_user_sdma_free_pkt_frag(struct device *dev,
248 struct ipath_user_sdma_queue *pq,
249 struct ipath_user_sdma_pkt *pkt,
250 int frag)
252 const int i = frag;
254 if (pkt->addr[i].page) {
255 if (pkt->addr[i].dma_mapped)
256 dma_unmap_page(dev,
257 pkt->addr[i].addr,
258 pkt->addr[i].length,
259 DMA_TO_DEVICE);
261 if (pkt->addr[i].kvaddr)
262 kunmap(pkt->addr[i].page);
264 if (pkt->addr[i].put_page)
265 put_page(pkt->addr[i].page);
266 else
267 __free_page(pkt->addr[i].page);
268 } else if (pkt->addr[i].kvaddr)
269 /* free coherent mem from cache... */
270 dma_pool_free(pq->header_cache,
271 pkt->addr[i].kvaddr, pkt->addr[i].addr);
274 /* return number of pages pinned... */
275 static int ipath_user_sdma_pin_pages(const struct ipath_devdata *dd,
276 struct ipath_user_sdma_pkt *pkt,
277 unsigned long addr, int tlen, int npages)
279 struct page *pages[2];
280 int j;
281 int ret;
283 ret = get_user_pages(current, current->mm, addr,
284 npages, 0, 1, pages, NULL);
286 if (ret != npages) {
287 int i;
289 for (i = 0; i < ret; i++)
290 put_page(pages[i]);
292 ret = -ENOMEM;
293 goto done;
296 for (j = 0; j < npages; j++) {
297 /* map the pages... */
298 const int flen =
299 ipath_user_sdma_page_length(addr, tlen);
300 dma_addr_t dma_addr =
301 dma_map_page(&dd->pcidev->dev,
302 pages[j], 0, flen, DMA_TO_DEVICE);
303 unsigned long fofs = addr & ~PAGE_MASK;
305 if (dma_mapping_error(&dd->pcidev->dev, dma_addr)) {
306 ret = -ENOMEM;
307 goto done;
310 ipath_user_sdma_init_frag(pkt, pkt->naddr, fofs, flen, 1, 1,
311 pages[j], kmap(pages[j]),
312 dma_addr);
314 pkt->naddr++;
315 addr += flen;
316 tlen -= flen;
319 done:
320 return ret;
323 static int ipath_user_sdma_pin_pkt(const struct ipath_devdata *dd,
324 struct ipath_user_sdma_queue *pq,
325 struct ipath_user_sdma_pkt *pkt,
326 const struct iovec *iov,
327 unsigned long niov)
329 int ret = 0;
330 unsigned long idx;
332 for (idx = 0; idx < niov; idx++) {
333 const int npages = ipath_user_sdma_num_pages(iov + idx);
334 const unsigned long addr = (unsigned long) iov[idx].iov_base;
336 ret = ipath_user_sdma_pin_pages(dd, pkt,
337 addr, iov[idx].iov_len,
338 npages);
339 if (ret < 0)
340 goto free_pkt;
343 goto done;
345 free_pkt:
346 for (idx = 0; idx < pkt->naddr; idx++)
347 ipath_user_sdma_free_pkt_frag(&dd->pcidev->dev, pq, pkt, idx);
349 done:
350 return ret;
353 static int ipath_user_sdma_init_payload(const struct ipath_devdata *dd,
354 struct ipath_user_sdma_queue *pq,
355 struct ipath_user_sdma_pkt *pkt,
356 const struct iovec *iov,
357 unsigned long niov, int npages)
359 int ret = 0;
361 if (npages >= ARRAY_SIZE(pkt->addr))
362 ret = ipath_user_sdma_coalesce(dd, pkt, iov, niov);
363 else
364 ret = ipath_user_sdma_pin_pkt(dd, pq, pkt, iov, niov);
366 return ret;
369 /* free a packet list -- return counter value of last packet */
370 static void ipath_user_sdma_free_pkt_list(struct device *dev,
371 struct ipath_user_sdma_queue *pq,
372 struct list_head *list)
374 struct ipath_user_sdma_pkt *pkt, *pkt_next;
376 list_for_each_entry_safe(pkt, pkt_next, list, list) {
377 int i;
379 for (i = 0; i < pkt->naddr; i++)
380 ipath_user_sdma_free_pkt_frag(dev, pq, pkt, i);
382 kmem_cache_free(pq->pkt_slab, pkt);
387 * copy headers, coalesce etc -- pq->lock must be held
389 * we queue all the packets to list, returning the
390 * number of bytes total. list must be empty initially,
391 * as, if there is an error we clean it...
393 static int ipath_user_sdma_queue_pkts(const struct ipath_devdata *dd,
394 struct ipath_user_sdma_queue *pq,
395 struct list_head *list,
396 const struct iovec *iov,
397 unsigned long niov,
398 int maxpkts)
400 unsigned long idx = 0;
401 int ret = 0;
402 int npkts = 0;
403 struct page *page = NULL;
404 __le32 *pbc;
405 dma_addr_t dma_addr;
406 struct ipath_user_sdma_pkt *pkt = NULL;
407 size_t len;
408 size_t nw;
409 u32 counter = pq->counter;
410 int dma_mapped = 0;
412 while (idx < niov && npkts < maxpkts) {
413 const unsigned long addr = (unsigned long) iov[idx].iov_base;
414 const unsigned long idx_save = idx;
415 unsigned pktnw;
416 unsigned pktnwc;
417 int nfrags = 0;
418 int npages = 0;
419 int cfur;
421 dma_mapped = 0;
422 len = iov[idx].iov_len;
423 nw = len >> 2;
424 page = NULL;
426 pkt = kmem_cache_alloc(pq->pkt_slab, GFP_KERNEL);
427 if (!pkt) {
428 ret = -ENOMEM;
429 goto free_list;
432 if (len < IPATH_USER_SDMA_MIN_HEADER_LENGTH ||
433 len > PAGE_SIZE || len & 3 || addr & 3) {
434 ret = -EINVAL;
435 goto free_pkt;
438 if (len == IPATH_USER_SDMA_EXP_HEADER_LENGTH)
439 pbc = dma_pool_alloc(pq->header_cache, GFP_KERNEL,
440 &dma_addr);
441 else
442 pbc = NULL;
444 if (!pbc) {
445 page = alloc_page(GFP_KERNEL);
446 if (!page) {
447 ret = -ENOMEM;
448 goto free_pkt;
450 pbc = kmap(page);
453 cfur = copy_from_user(pbc, iov[idx].iov_base, len);
454 if (cfur) {
455 ret = -EFAULT;
456 goto free_pbc;
460 * this assignment is a bit strange. it's because the
461 * the pbc counts the number of 32 bit words in the full
462 * packet _except_ the first word of the pbc itself...
464 pktnwc = nw - 1;
467 * pktnw computation yields the number of 32 bit words
468 * that the caller has indicated in the PBC. note that
469 * this is one less than the total number of words that
470 * goes to the send DMA engine as the first 32 bit word
471 * of the PBC itself is not counted. Armed with this count,
472 * we can verify that the packet is consistent with the
473 * iovec lengths.
475 pktnw = le32_to_cpu(*pbc) & IPATH_PBC_LENGTH_MASK;
476 if (pktnw < pktnwc || pktnw > pktnwc + (PAGE_SIZE >> 2)) {
477 ret = -EINVAL;
478 goto free_pbc;
482 idx++;
483 while (pktnwc < pktnw && idx < niov) {
484 const size_t slen = iov[idx].iov_len;
485 const unsigned long faddr =
486 (unsigned long) iov[idx].iov_base;
488 if (slen & 3 || faddr & 3 || !slen ||
489 slen > PAGE_SIZE) {
490 ret = -EINVAL;
491 goto free_pbc;
494 npages++;
495 if ((faddr & PAGE_MASK) !=
496 ((faddr + slen - 1) & PAGE_MASK))
497 npages++;
499 pktnwc += slen >> 2;
500 idx++;
501 nfrags++;
504 if (pktnwc != pktnw) {
505 ret = -EINVAL;
506 goto free_pbc;
509 if (page) {
510 dma_addr = dma_map_page(&dd->pcidev->dev,
511 page, 0, len, DMA_TO_DEVICE);
512 if (dma_mapping_error(&dd->pcidev->dev, dma_addr)) {
513 ret = -ENOMEM;
514 goto free_pbc;
517 dma_mapped = 1;
520 ipath_user_sdma_init_header(pkt, counter, 0, len, dma_mapped,
521 page, pbc, dma_addr);
523 if (nfrags) {
524 ret = ipath_user_sdma_init_payload(dd, pq, pkt,
525 iov + idx_save + 1,
526 nfrags, npages);
527 if (ret < 0)
528 goto free_pbc_dma;
531 counter++;
532 npkts++;
534 list_add_tail(&pkt->list, list);
537 ret = idx;
538 goto done;
540 free_pbc_dma:
541 if (dma_mapped)
542 dma_unmap_page(&dd->pcidev->dev, dma_addr, len, DMA_TO_DEVICE);
543 free_pbc:
544 if (page) {
545 kunmap(page);
546 __free_page(page);
547 } else
548 dma_pool_free(pq->header_cache, pbc, dma_addr);
549 free_pkt:
550 kmem_cache_free(pq->pkt_slab, pkt);
551 free_list:
552 ipath_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, list);
553 done:
554 return ret;
557 static void ipath_user_sdma_set_complete_counter(struct ipath_user_sdma_queue *pq,
558 u32 c)
560 pq->sent_counter = c;
563 /* try to clean out queue -- needs pq->lock */
564 static int ipath_user_sdma_queue_clean(const struct ipath_devdata *dd,
565 struct ipath_user_sdma_queue *pq)
567 struct list_head free_list;
568 struct ipath_user_sdma_pkt *pkt;
569 struct ipath_user_sdma_pkt *pkt_prev;
570 int ret = 0;
572 INIT_LIST_HEAD(&free_list);
574 list_for_each_entry_safe(pkt, pkt_prev, &pq->sent, list) {
575 s64 descd = dd->ipath_sdma_descq_removed - pkt->added;
577 if (descd < 0)
578 break;
580 list_move_tail(&pkt->list, &free_list);
582 /* one more packet cleaned */
583 ret++;
586 if (!list_empty(&free_list)) {
587 u32 counter;
589 pkt = list_entry(free_list.prev,
590 struct ipath_user_sdma_pkt, list);
591 counter = pkt->counter;
593 ipath_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &free_list);
594 ipath_user_sdma_set_complete_counter(pq, counter);
597 return ret;
600 void ipath_user_sdma_queue_destroy(struct ipath_user_sdma_queue *pq)
602 if (!pq)
603 return;
605 kmem_cache_destroy(pq->pkt_slab);
606 dma_pool_destroy(pq->header_cache);
607 kfree(pq);
610 /* clean descriptor queue, returns > 0 if some elements cleaned */
611 static int ipath_user_sdma_hwqueue_clean(struct ipath_devdata *dd)
613 int ret;
614 unsigned long flags;
616 spin_lock_irqsave(&dd->ipath_sdma_lock, flags);
617 ret = ipath_sdma_make_progress(dd);
618 spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
620 return ret;
623 /* we're in close, drain packets so that we can cleanup successfully... */
624 void ipath_user_sdma_queue_drain(struct ipath_devdata *dd,
625 struct ipath_user_sdma_queue *pq)
627 int i;
629 if (!pq)
630 return;
632 for (i = 0; i < 100; i++) {
633 mutex_lock(&pq->lock);
634 if (list_empty(&pq->sent)) {
635 mutex_unlock(&pq->lock);
636 break;
638 ipath_user_sdma_hwqueue_clean(dd);
639 ipath_user_sdma_queue_clean(dd, pq);
640 mutex_unlock(&pq->lock);
641 msleep(10);
644 if (!list_empty(&pq->sent)) {
645 struct list_head free_list;
647 printk(KERN_INFO "drain: lists not empty: forcing!\n");
648 INIT_LIST_HEAD(&free_list);
649 mutex_lock(&pq->lock);
650 list_splice_init(&pq->sent, &free_list);
651 ipath_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &free_list);
652 mutex_unlock(&pq->lock);
656 static inline __le64 ipath_sdma_make_desc0(struct ipath_devdata *dd,
657 u64 addr, u64 dwlen, u64 dwoffset)
659 return cpu_to_le64(/* SDmaPhyAddr[31:0] */
660 ((addr & 0xfffffffcULL) << 32) |
661 /* SDmaGeneration[1:0] */
662 ((dd->ipath_sdma_generation & 3ULL) << 30) |
663 /* SDmaDwordCount[10:0] */
664 ((dwlen & 0x7ffULL) << 16) |
665 /* SDmaBufOffset[12:2] */
666 (dwoffset & 0x7ffULL));
669 static inline __le64 ipath_sdma_make_first_desc0(__le64 descq)
671 return descq | cpu_to_le64(1ULL << 12);
674 static inline __le64 ipath_sdma_make_last_desc0(__le64 descq)
676 /* last */ /* dma head */
677 return descq | cpu_to_le64(1ULL << 11 | 1ULL << 13);
680 static inline __le64 ipath_sdma_make_desc1(u64 addr)
682 /* SDmaPhyAddr[47:32] */
683 return cpu_to_le64(addr >> 32);
686 static void ipath_user_sdma_send_frag(struct ipath_devdata *dd,
687 struct ipath_user_sdma_pkt *pkt, int idx,
688 unsigned ofs, u16 tail)
690 const u64 addr = (u64) pkt->addr[idx].addr +
691 (u64) pkt->addr[idx].offset;
692 const u64 dwlen = (u64) pkt->addr[idx].length / 4;
693 __le64 *descqp;
694 __le64 descq0;
696 descqp = &dd->ipath_sdma_descq[tail].qw[0];
698 descq0 = ipath_sdma_make_desc0(dd, addr, dwlen, ofs);
699 if (idx == 0)
700 descq0 = ipath_sdma_make_first_desc0(descq0);
701 if (idx == pkt->naddr - 1)
702 descq0 = ipath_sdma_make_last_desc0(descq0);
704 descqp[0] = descq0;
705 descqp[1] = ipath_sdma_make_desc1(addr);
708 /* pq->lock must be held, get packets on the wire... */
709 static int ipath_user_sdma_push_pkts(struct ipath_devdata *dd,
710 struct ipath_user_sdma_queue *pq,
711 struct list_head *pktlist)
713 int ret = 0;
714 unsigned long flags;
715 u16 tail;
717 if (list_empty(pktlist))
718 return 0;
720 if (unlikely(!(dd->ipath_flags & IPATH_LINKACTIVE)))
721 return -ECOMM;
723 spin_lock_irqsave(&dd->ipath_sdma_lock, flags);
725 if (unlikely(dd->ipath_sdma_status & IPATH_SDMA_ABORT_MASK)) {
726 ret = -ECOMM;
727 goto unlock;
730 tail = dd->ipath_sdma_descq_tail;
731 while (!list_empty(pktlist)) {
732 struct ipath_user_sdma_pkt *pkt =
733 list_entry(pktlist->next, struct ipath_user_sdma_pkt,
734 list);
735 int i;
736 unsigned ofs = 0;
737 u16 dtail = tail;
739 if (pkt->naddr > ipath_sdma_descq_freecnt(dd))
740 goto unlock_check_tail;
742 for (i = 0; i < pkt->naddr; i++) {
743 ipath_user_sdma_send_frag(dd, pkt, i, ofs, tail);
744 ofs += pkt->addr[i].length >> 2;
746 if (++tail == dd->ipath_sdma_descq_cnt) {
747 tail = 0;
748 ++dd->ipath_sdma_generation;
752 if ((ofs<<2) > dd->ipath_ibmaxlen) {
753 ipath_dbg("packet size %X > ibmax %X, fail\n",
754 ofs<<2, dd->ipath_ibmaxlen);
755 ret = -EMSGSIZE;
756 goto unlock;
760 * if the packet is >= 2KB mtu equivalent, we have to use
761 * the large buffers, and have to mark each descriptor as
762 * part of a large buffer packet.
764 if (ofs >= IPATH_SMALLBUF_DWORDS) {
765 for (i = 0; i < pkt->naddr; i++) {
766 dd->ipath_sdma_descq[dtail].qw[0] |=
767 cpu_to_le64(1ULL << 14);
768 if (++dtail == dd->ipath_sdma_descq_cnt)
769 dtail = 0;
773 dd->ipath_sdma_descq_added += pkt->naddr;
774 pkt->added = dd->ipath_sdma_descq_added;
775 list_move_tail(&pkt->list, &pq->sent);
776 ret++;
779 unlock_check_tail:
780 /* advance the tail on the chip if necessary */
781 if (dd->ipath_sdma_descq_tail != tail) {
782 wmb();
783 ipath_write_kreg(dd, dd->ipath_kregs->kr_senddmatail, tail);
784 dd->ipath_sdma_descq_tail = tail;
787 unlock:
788 spin_unlock_irqrestore(&dd->ipath_sdma_lock, flags);
790 return ret;
793 int ipath_user_sdma_writev(struct ipath_devdata *dd,
794 struct ipath_user_sdma_queue *pq,
795 const struct iovec *iov,
796 unsigned long dim)
798 int ret = 0;
799 struct list_head list;
800 int npkts = 0;
802 INIT_LIST_HEAD(&list);
804 mutex_lock(&pq->lock);
806 if (dd->ipath_sdma_descq_added != dd->ipath_sdma_descq_removed) {
807 ipath_user_sdma_hwqueue_clean(dd);
808 ipath_user_sdma_queue_clean(dd, pq);
811 while (dim) {
812 const int mxp = 8;
814 down_write(&current->mm->mmap_sem);
815 ret = ipath_user_sdma_queue_pkts(dd, pq, &list, iov, dim, mxp);
816 up_write(&current->mm->mmap_sem);
818 if (ret <= 0)
819 goto done_unlock;
820 else {
821 dim -= ret;
822 iov += ret;
825 /* force packets onto the sdma hw queue... */
826 if (!list_empty(&list)) {
828 * lazily clean hw queue. the 4 is a guess of about
829 * how many sdma descriptors a packet will take (it
830 * doesn't have to be perfect).
832 if (ipath_sdma_descq_freecnt(dd) < ret * 4) {
833 ipath_user_sdma_hwqueue_clean(dd);
834 ipath_user_sdma_queue_clean(dd, pq);
837 ret = ipath_user_sdma_push_pkts(dd, pq, &list);
838 if (ret < 0)
839 goto done_unlock;
840 else {
841 npkts += ret;
842 pq->counter += ret;
844 if (!list_empty(&list))
845 goto done_unlock;
850 done_unlock:
851 if (!list_empty(&list))
852 ipath_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &list);
853 mutex_unlock(&pq->lock);
855 return (ret < 0) ? ret : npkts;
858 int ipath_user_sdma_make_progress(struct ipath_devdata *dd,
859 struct ipath_user_sdma_queue *pq)
861 int ret = 0;
863 mutex_lock(&pq->lock);
864 ipath_user_sdma_hwqueue_clean(dd);
865 ret = ipath_user_sdma_queue_clean(dd, pq);
866 mutex_unlock(&pq->lock);
868 return ret;
871 u32 ipath_user_sdma_complete_counter(const struct ipath_user_sdma_queue *pq)
873 return pq->sent_counter;
876 u32 ipath_user_sdma_inflight_counter(struct ipath_user_sdma_queue *pq)
878 return pq->counter;