Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / drivers / infiniband / hw / qib / qib_user_sdma.c
blob926f3c8eba69fa6e07f86a3777fb0d89fc92d823
1 /*
2 * Copyright (c) 2007, 2008, 2009 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/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>
45 #include "qib.h"
46 #include "qib_user_sdma.h"
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
56 * track how many times a process open this driver.
58 static struct rb_root qib_user_sdma_rb_root = RB_ROOT;
60 struct qib_user_sdma_rb_node {
61 struct rb_node node;
62 int refcount;
63 pid_t pid;
66 struct qib_user_sdma_pkt {
67 struct list_head list; /* list element */
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 */
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 */
99 struct qib_user_sdma_queue {
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...
105 struct list_head sent;
108 * Because above list will be accessed by both process and
109 * signal handler, we need a spinlock for it.
111 spinlock_t sent_lock ____cacheline_aligned_in_smp;
113 /* headers with expected length are allocated from here... */
114 char header_cache_name[64];
115 struct dma_pool *header_cache;
117 /* packets are allocated from the slab cache... */
118 char pkt_slab_name[64];
119 struct kmem_cache *pkt_slab;
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;
131 /* dma page table */
132 struct rb_root dma_pages_root;
134 struct qib_user_sdma_rb_node *sdma_rb_node;
136 /* protect everything above... */
137 struct mutex lock;
140 static struct qib_user_sdma_rb_node *
141 qib_user_sdma_rb_search(struct rb_root *root, pid_t pid)
143 struct qib_user_sdma_rb_node *sdma_rb_node;
144 struct rb_node *node = root->rb_node;
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;
156 return NULL;
159 static int
160 qib_user_sdma_rb_insert(struct rb_root *root, struct qib_user_sdma_rb_node *new)
162 struct rb_node **node = &(root->rb_node);
163 struct rb_node *parent = NULL;
164 struct qib_user_sdma_rb_node *got;
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;
177 rb_link_node(&new->node, parent, node);
178 rb_insert_color(&new->node, root);
179 return 1;
182 struct qib_user_sdma_queue *
183 qib_user_sdma_queue_create(struct device *dev, int unit, int ctxt, int sctxt)
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;
189 if (!pq)
190 goto done;
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;
199 INIT_LIST_HEAD(&pq->sent);
200 spin_lock_init(&pq->sent_lock);
201 mutex_init(&pq->lock);
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);
209 if (!pq->pkt_slab)
210 goto err_kfree;
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;
221 pq->dma_pages_root = RB_ROOT;
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 int ret;
230 sdma_rb_node = kmalloc(sizeof(
231 struct qib_user_sdma_rb_node), GFP_KERNEL);
232 if (!sdma_rb_node)
233 goto err_rb;
235 sdma_rb_node->refcount = 1;
236 sdma_rb_node->pid = current->pid;
238 ret = qib_user_sdma_rb_insert(&qib_user_sdma_rb_root,
239 sdma_rb_node);
240 BUG_ON(ret == 0);
242 pq->sdma_rb_node = sdma_rb_node;
244 goto done;
246 err_rb:
247 dma_pool_destroy(pq->header_cache);
248 err_slab:
249 kmem_cache_destroy(pq->pkt_slab);
250 err_kfree:
251 kfree(pq);
252 pq = NULL;
254 done:
255 return pq;
258 static void qib_user_sdma_init_frag(struct qib_user_sdma_pkt *pkt,
259 int i, u16 offset, u16 len,
260 u16 first_desc, u16 last_desc,
261 u16 put_page, u16 dma_mapped,
262 struct page *page, void *kvaddr,
263 dma_addr_t dma_addr, u16 dma_length)
265 pkt->addr[i].offset = offset;
266 pkt->addr[i].length = len;
267 pkt->addr[i].first_desc = first_desc;
268 pkt->addr[i].last_desc = last_desc;
269 pkt->addr[i].put_page = put_page;
270 pkt->addr[i].dma_mapped = dma_mapped;
271 pkt->addr[i].page = page;
272 pkt->addr[i].kvaddr = kvaddr;
273 pkt->addr[i].addr = dma_addr;
274 pkt->addr[i].dma_length = dma_length;
277 static void *qib_user_sdma_alloc_header(struct qib_user_sdma_queue *pq,
278 size_t len, dma_addr_t *dma_addr)
280 void *hdr;
282 if (len == QIB_USER_SDMA_EXP_HEADER_LENGTH)
283 hdr = dma_pool_alloc(pq->header_cache, GFP_KERNEL,
284 dma_addr);
285 else
286 hdr = NULL;
288 if (!hdr) {
289 hdr = kmalloc(len, GFP_KERNEL);
290 if (!hdr)
291 return NULL;
293 *dma_addr = 0;
296 return hdr;
299 static int qib_user_sdma_page_to_frags(const struct qib_devdata *dd,
300 struct qib_user_sdma_queue *pq,
301 struct qib_user_sdma_pkt *pkt,
302 struct page *page, u16 put,
303 u16 offset, u16 len, void *kvaddr)
305 __le16 *pbc16;
306 void *pbcvaddr;
307 struct qib_message_header *hdr;
308 u16 newlen, pbclen, lastdesc, dma_mapped;
309 u32 vcto;
310 union qib_seqnum seqnum;
311 dma_addr_t pbcdaddr;
312 dma_addr_t dma_addr =
313 dma_map_page(&dd->pcidev->dev,
314 page, offset, len, DMA_TO_DEVICE);
315 int ret = 0;
317 if (dma_mapping_error(&dd->pcidev->dev, dma_addr)) {
319 * dma mapping error, pkt has not managed
320 * this page yet, return the page here so
321 * the caller can ignore this page.
323 if (put) {
324 put_page(page);
325 } else {
326 /* coalesce case */
327 kunmap(page);
328 __free_page(page);
330 ret = -ENOMEM;
331 goto done;
333 offset = 0;
334 dma_mapped = 1;
337 next_fragment:
340 * In tid-sdma, the transfer length is restricted by
341 * receiver side current tid page length.
343 if (pkt->tiddma && len > pkt->tidsm[pkt->tidsmidx].length)
344 newlen = pkt->tidsm[pkt->tidsmidx].length;
345 else
346 newlen = len;
349 * Then the transfer length is restricted by MTU.
350 * the last descriptor flag is determined by:
351 * 1. the current packet is at frag size length.
352 * 2. the current tid page is done if tid-sdma.
353 * 3. there is no more byte togo if sdma.
355 lastdesc = 0;
356 if ((pkt->payload_size + newlen) >= pkt->frag_size) {
357 newlen = pkt->frag_size - pkt->payload_size;
358 lastdesc = 1;
359 } else if (pkt->tiddma) {
360 if (newlen == pkt->tidsm[pkt->tidsmidx].length)
361 lastdesc = 1;
362 } else {
363 if (newlen == pkt->bytes_togo)
364 lastdesc = 1;
367 /* fill the next fragment in this page */
368 qib_user_sdma_init_frag(pkt, pkt->naddr, /* index */
369 offset, newlen, /* offset, len */
370 0, lastdesc, /* first last desc */
371 put, dma_mapped, /* put page, dma mapped */
372 page, kvaddr, /* struct page, virt addr */
373 dma_addr, len); /* dma addr, dma length */
374 pkt->bytes_togo -= newlen;
375 pkt->payload_size += newlen;
376 pkt->naddr++;
377 if (pkt->naddr == pkt->addrlimit) {
378 ret = -EFAULT;
379 goto done;
382 /* If there is no more byte togo. (lastdesc==1) */
383 if (pkt->bytes_togo == 0) {
384 /* The packet is done, header is not dma mapped yet.
385 * it should be from kmalloc */
386 if (!pkt->addr[pkt->index].addr) {
387 pkt->addr[pkt->index].addr =
388 dma_map_single(&dd->pcidev->dev,
389 pkt->addr[pkt->index].kvaddr,
390 pkt->addr[pkt->index].dma_length,
391 DMA_TO_DEVICE);
392 if (dma_mapping_error(&dd->pcidev->dev,
393 pkt->addr[pkt->index].addr)) {
394 ret = -ENOMEM;
395 goto done;
397 pkt->addr[pkt->index].dma_mapped = 1;
400 goto done;
403 /* If tid-sdma, advance tid info. */
404 if (pkt->tiddma) {
405 pkt->tidsm[pkt->tidsmidx].length -= newlen;
406 if (pkt->tidsm[pkt->tidsmidx].length) {
407 pkt->tidsm[pkt->tidsmidx].offset += newlen;
408 } else {
409 pkt->tidsmidx++;
410 if (pkt->tidsmidx == pkt->tidsmcount) {
411 ret = -EFAULT;
412 goto done;
418 * If this is NOT the last descriptor. (newlen==len)
419 * the current packet is not done yet, but the current
420 * send side page is done.
422 if (lastdesc == 0)
423 goto done;
426 * If running this driver under PSM with message size
427 * fitting into one transfer unit, it is not possible
428 * to pass this line. otherwise, it is a buggggg.
432 * Since the current packet is done, and there are more
433 * bytes togo, we need to create a new sdma header, copying
434 * from previous sdma header and modify both.
436 pbclen = pkt->addr[pkt->index].length;
437 pbcvaddr = qib_user_sdma_alloc_header(pq, pbclen, &pbcdaddr);
438 if (!pbcvaddr) {
439 ret = -ENOMEM;
440 goto done;
442 /* Copy the previous sdma header to new sdma header */
443 pbc16 = (__le16 *)pkt->addr[pkt->index].kvaddr;
444 memcpy(pbcvaddr, pbc16, pbclen);
446 /* Modify the previous sdma header */
447 hdr = (struct qib_message_header *)&pbc16[4];
449 /* New pbc length */
450 pbc16[0] = cpu_to_le16(le16_to_cpu(pbc16[0])-(pkt->bytes_togo>>2));
452 /* New packet length */
453 hdr->lrh[2] = cpu_to_be16(le16_to_cpu(pbc16[0]));
455 if (pkt->tiddma) {
456 /* turn on the header suppression */
457 hdr->iph.pkt_flags =
458 cpu_to_le16(le16_to_cpu(hdr->iph.pkt_flags)|0x2);
459 /* turn off ACK_REQ: 0x04 and EXPECTED_DONE: 0x20 */
460 hdr->flags &= ~(0x04|0x20);
461 } else {
462 /* turn off extra bytes: 20-21 bits */
463 hdr->bth[0] = cpu_to_be32(be32_to_cpu(hdr->bth[0])&0xFFCFFFFF);
464 /* turn off ACK_REQ: 0x04 */
465 hdr->flags &= ~(0x04);
468 /* New kdeth checksum */
469 vcto = le32_to_cpu(hdr->iph.ver_ctxt_tid_offset);
470 hdr->iph.chksum = cpu_to_le16(QIB_LRH_BTH +
471 be16_to_cpu(hdr->lrh[2]) -
472 ((vcto>>16)&0xFFFF) - (vcto&0xFFFF) -
473 le16_to_cpu(hdr->iph.pkt_flags));
475 /* The packet is done, header is not dma mapped yet.
476 * it should be from kmalloc */
477 if (!pkt->addr[pkt->index].addr) {
478 pkt->addr[pkt->index].addr =
479 dma_map_single(&dd->pcidev->dev,
480 pkt->addr[pkt->index].kvaddr,
481 pkt->addr[pkt->index].dma_length,
482 DMA_TO_DEVICE);
483 if (dma_mapping_error(&dd->pcidev->dev,
484 pkt->addr[pkt->index].addr)) {
485 ret = -ENOMEM;
486 goto done;
488 pkt->addr[pkt->index].dma_mapped = 1;
491 /* Modify the new sdma header */
492 pbc16 = (__le16 *)pbcvaddr;
493 hdr = (struct qib_message_header *)&pbc16[4];
495 /* New pbc length */
496 pbc16[0] = cpu_to_le16(le16_to_cpu(pbc16[0])-(pkt->payload_size>>2));
498 /* New packet length */
499 hdr->lrh[2] = cpu_to_be16(le16_to_cpu(pbc16[0]));
501 if (pkt->tiddma) {
502 /* Set new tid and offset for new sdma header */
503 hdr->iph.ver_ctxt_tid_offset = cpu_to_le32(
504 (le32_to_cpu(hdr->iph.ver_ctxt_tid_offset)&0xFF000000) +
505 (pkt->tidsm[pkt->tidsmidx].tid<<QLOGIC_IB_I_TID_SHIFT) +
506 (pkt->tidsm[pkt->tidsmidx].offset>>2));
507 } else {
508 /* Middle protocol new packet offset */
509 hdr->uwords[2] += pkt->payload_size;
512 /* New kdeth checksum */
513 vcto = le32_to_cpu(hdr->iph.ver_ctxt_tid_offset);
514 hdr->iph.chksum = cpu_to_le16(QIB_LRH_BTH +
515 be16_to_cpu(hdr->lrh[2]) -
516 ((vcto>>16)&0xFFFF) - (vcto&0xFFFF) -
517 le16_to_cpu(hdr->iph.pkt_flags));
519 /* Next sequence number in new sdma header */
520 seqnum.val = be32_to_cpu(hdr->bth[2]);
521 if (pkt->tiddma)
522 seqnum.seq++;
523 else
524 seqnum.pkt++;
525 hdr->bth[2] = cpu_to_be32(seqnum.val);
527 /* Init new sdma header. */
528 qib_user_sdma_init_frag(pkt, pkt->naddr, /* index */
529 0, pbclen, /* offset, len */
530 1, 0, /* first last desc */
531 0, 0, /* put page, dma mapped */
532 NULL, pbcvaddr, /* struct page, virt addr */
533 pbcdaddr, pbclen); /* dma addr, dma length */
534 pkt->index = pkt->naddr;
535 pkt->payload_size = 0;
536 pkt->naddr++;
537 if (pkt->naddr == pkt->addrlimit) {
538 ret = -EFAULT;
539 goto done;
542 /* Prepare for next fragment in this page */
543 if (newlen != len) {
544 if (dma_mapped) {
545 put = 0;
546 dma_mapped = 0;
547 page = NULL;
548 kvaddr = NULL;
550 len -= newlen;
551 offset += newlen;
553 goto next_fragment;
556 done:
557 return ret;
560 /* we've too many pages in the iovec, coalesce to a single page */
561 static int qib_user_sdma_coalesce(const struct qib_devdata *dd,
562 struct qib_user_sdma_queue *pq,
563 struct qib_user_sdma_pkt *pkt,
564 const struct iovec *iov,
565 unsigned long niov)
567 int ret = 0;
568 struct page *page = alloc_page(GFP_KERNEL);
569 void *mpage_save;
570 char *mpage;
571 int i;
572 int len = 0;
574 if (!page) {
575 ret = -ENOMEM;
576 goto done;
579 mpage = kmap(page);
580 mpage_save = mpage;
581 for (i = 0; i < niov; i++) {
582 int cfur;
584 cfur = copy_from_user(mpage,
585 iov[i].iov_base, iov[i].iov_len);
586 if (cfur) {
587 ret = -EFAULT;
588 goto free_unmap;
591 mpage += iov[i].iov_len;
592 len += iov[i].iov_len;
595 ret = qib_user_sdma_page_to_frags(dd, pq, pkt,
596 page, 0, 0, len, mpage_save);
597 goto done;
599 free_unmap:
600 kunmap(page);
601 __free_page(page);
602 done:
603 return ret;
607 * How many pages in this iovec element?
609 static int qib_user_sdma_num_pages(const struct iovec *iov)
611 const unsigned long addr = (unsigned long) iov->iov_base;
612 const unsigned long len = iov->iov_len;
613 const unsigned long spage = addr & PAGE_MASK;
614 const unsigned long epage = (addr + len - 1) & PAGE_MASK;
616 return 1 + ((epage - spage) >> PAGE_SHIFT);
619 static void qib_user_sdma_free_pkt_frag(struct device *dev,
620 struct qib_user_sdma_queue *pq,
621 struct qib_user_sdma_pkt *pkt,
622 int frag)
624 const int i = frag;
626 if (pkt->addr[i].page) {
627 /* only user data has page */
628 if (pkt->addr[i].dma_mapped)
629 dma_unmap_page(dev,
630 pkt->addr[i].addr,
631 pkt->addr[i].dma_length,
632 DMA_TO_DEVICE);
634 if (pkt->addr[i].kvaddr)
635 kunmap(pkt->addr[i].page);
637 if (pkt->addr[i].put_page)
638 put_page(pkt->addr[i].page);
639 else
640 __free_page(pkt->addr[i].page);
641 } else if (pkt->addr[i].kvaddr) {
642 /* for headers */
643 if (pkt->addr[i].dma_mapped) {
644 /* from kmalloc & dma mapped */
645 dma_unmap_single(dev,
646 pkt->addr[i].addr,
647 pkt->addr[i].dma_length,
648 DMA_TO_DEVICE);
649 kfree(pkt->addr[i].kvaddr);
650 } else if (pkt->addr[i].addr) {
651 /* free coherent mem from cache... */
652 dma_pool_free(pq->header_cache,
653 pkt->addr[i].kvaddr, pkt->addr[i].addr);
654 } else {
655 /* from kmalloc but not dma mapped */
656 kfree(pkt->addr[i].kvaddr);
661 /* return number of pages pinned... */
662 static int qib_user_sdma_pin_pages(const struct qib_devdata *dd,
663 struct qib_user_sdma_queue *pq,
664 struct qib_user_sdma_pkt *pkt,
665 unsigned long addr, int tlen, int npages)
667 struct page *pages[8];
668 int i, j;
669 int ret = 0;
671 while (npages) {
672 if (npages > 8)
673 j = 8;
674 else
675 j = npages;
677 ret = get_user_pages_fast(addr, j, 0, pages);
678 if (ret != j) {
679 i = 0;
680 j = ret;
681 ret = -ENOMEM;
682 goto free_pages;
685 for (i = 0; i < j; i++) {
686 /* map the pages... */
687 unsigned long fofs = addr & ~PAGE_MASK;
688 int flen = ((fofs + tlen) > PAGE_SIZE) ?
689 (PAGE_SIZE - fofs) : tlen;
691 ret = qib_user_sdma_page_to_frags(dd, pq, pkt,
692 pages[i], 1, fofs, flen, NULL);
693 if (ret < 0) {
694 /* current page has beed taken
695 * care of inside above call.
697 i++;
698 goto free_pages;
701 addr += flen;
702 tlen -= flen;
705 npages -= j;
708 goto done;
710 /* if error, return all pages not managed by pkt */
711 free_pages:
712 while (i < j)
713 put_page(pages[i++]);
715 done:
716 return ret;
719 static int qib_user_sdma_pin_pkt(const struct qib_devdata *dd,
720 struct qib_user_sdma_queue *pq,
721 struct qib_user_sdma_pkt *pkt,
722 const struct iovec *iov,
723 unsigned long niov)
725 int ret = 0;
726 unsigned long idx;
728 for (idx = 0; idx < niov; idx++) {
729 const int npages = qib_user_sdma_num_pages(iov + idx);
730 const unsigned long addr = (unsigned long) iov[idx].iov_base;
732 ret = qib_user_sdma_pin_pages(dd, pq, pkt, addr,
733 iov[idx].iov_len, npages);
734 if (ret < 0)
735 goto free_pkt;
738 goto done;
740 free_pkt:
741 /* we need to ignore the first entry here */
742 for (idx = 1; idx < pkt->naddr; idx++)
743 qib_user_sdma_free_pkt_frag(&dd->pcidev->dev, pq, pkt, idx);
745 /* need to dma unmap the first entry, this is to restore to
746 * the original state so that caller can free the memory in
747 * error condition. Caller does not know if dma mapped or not*/
748 if (pkt->addr[0].dma_mapped) {
749 dma_unmap_single(&dd->pcidev->dev,
750 pkt->addr[0].addr,
751 pkt->addr[0].dma_length,
752 DMA_TO_DEVICE);
753 pkt->addr[0].addr = 0;
754 pkt->addr[0].dma_mapped = 0;
757 done:
758 return ret;
761 static int qib_user_sdma_init_payload(const struct qib_devdata *dd,
762 struct qib_user_sdma_queue *pq,
763 struct qib_user_sdma_pkt *pkt,
764 const struct iovec *iov,
765 unsigned long niov, int npages)
767 int ret = 0;
769 if (pkt->frag_size == pkt->bytes_togo &&
770 npages >= ARRAY_SIZE(pkt->addr))
771 ret = qib_user_sdma_coalesce(dd, pq, pkt, iov, niov);
772 else
773 ret = qib_user_sdma_pin_pkt(dd, pq, pkt, iov, niov);
775 return ret;
778 /* free a packet list -- return counter value of last packet */
779 static void qib_user_sdma_free_pkt_list(struct device *dev,
780 struct qib_user_sdma_queue *pq,
781 struct list_head *list)
783 struct qib_user_sdma_pkt *pkt, *pkt_next;
785 list_for_each_entry_safe(pkt, pkt_next, list, list) {
786 int i;
788 for (i = 0; i < pkt->naddr; i++)
789 qib_user_sdma_free_pkt_frag(dev, pq, pkt, i);
791 if (pkt->largepkt)
792 kfree(pkt);
793 else
794 kmem_cache_free(pq->pkt_slab, pkt);
796 INIT_LIST_HEAD(list);
800 * copy headers, coalesce etc -- pq->lock must be held
802 * we queue all the packets to list, returning the
803 * number of bytes total. list must be empty initially,
804 * as, if there is an error we clean it...
806 static int qib_user_sdma_queue_pkts(const struct qib_devdata *dd,
807 struct qib_pportdata *ppd,
808 struct qib_user_sdma_queue *pq,
809 const struct iovec *iov,
810 unsigned long niov,
811 struct list_head *list,
812 int *maxpkts, int *ndesc)
814 unsigned long idx = 0;
815 int ret = 0;
816 int npkts = 0;
817 __le32 *pbc;
818 dma_addr_t dma_addr;
819 struct qib_user_sdma_pkt *pkt = NULL;
820 size_t len;
821 size_t nw;
822 u32 counter = pq->counter;
823 u16 frag_size;
825 while (idx < niov && npkts < *maxpkts) {
826 const unsigned long addr = (unsigned long) iov[idx].iov_base;
827 const unsigned long idx_save = idx;
828 unsigned pktnw;
829 unsigned pktnwc;
830 int nfrags = 0;
831 int npages = 0;
832 int bytes_togo = 0;
833 int tiddma = 0;
834 int cfur;
836 len = iov[idx].iov_len;
837 nw = len >> 2;
839 if (len < QIB_USER_SDMA_MIN_HEADER_LENGTH ||
840 len > PAGE_SIZE || len & 3 || addr & 3) {
841 ret = -EINVAL;
842 goto free_list;
845 pbc = qib_user_sdma_alloc_header(pq, len, &dma_addr);
846 if (!pbc) {
847 ret = -ENOMEM;
848 goto free_list;
851 cfur = copy_from_user(pbc, iov[idx].iov_base, len);
852 if (cfur) {
853 ret = -EFAULT;
854 goto free_pbc;
858 * This assignment is a bit strange. it's because the
859 * the pbc counts the number of 32 bit words in the full
860 * packet _except_ the first word of the pbc itself...
862 pktnwc = nw - 1;
865 * pktnw computation yields the number of 32 bit words
866 * that the caller has indicated in the PBC. note that
867 * this is one less than the total number of words that
868 * goes to the send DMA engine as the first 32 bit word
869 * of the PBC itself is not counted. Armed with this count,
870 * we can verify that the packet is consistent with the
871 * iovec lengths.
873 pktnw = le32_to_cpu(*pbc) & 0xFFFF;
874 if (pktnw < pktnwc) {
875 ret = -EINVAL;
876 goto free_pbc;
879 idx++;
880 while (pktnwc < pktnw && idx < niov) {
881 const size_t slen = iov[idx].iov_len;
882 const unsigned long faddr =
883 (unsigned long) iov[idx].iov_base;
885 if (slen & 3 || faddr & 3 || !slen) {
886 ret = -EINVAL;
887 goto free_pbc;
890 npages += qib_user_sdma_num_pages(&iov[idx]);
892 bytes_togo += slen;
893 pktnwc += slen >> 2;
894 idx++;
895 nfrags++;
898 if (pktnwc != pktnw) {
899 ret = -EINVAL;
900 goto free_pbc;
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;
910 if (frag_size) {
911 int pktsize, tidsmsize, n;
913 n = npages*((2*PAGE_SIZE/frag_size)+1);
914 pktsize = sizeof(*pkt) + sizeof(pkt->addr[0])*n;
917 * Determine if this is tid-sdma or just sdma.
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);
924 if (tiddma)
925 tidsmsize = iov[idx].iov_len;
926 else
927 tidsmsize = 0;
929 pkt = kmalloc(pktsize+tidsmsize, GFP_KERNEL);
930 if (!pkt) {
931 ret = -ENOMEM;
932 goto free_pbc;
934 pkt->largepkt = 1;
935 pkt->frag_size = frag_size;
936 pkt->addrlimit = n + ARRAY_SIZE(pkt->addr);
938 if (tiddma) {
939 char *tidsm = (char *)pkt + pktsize;
941 cfur = copy_from_user(tidsm,
942 iov[idx].iov_base, tidsmsize);
943 if (cfur) {
944 ret = -EFAULT;
945 goto free_pkt;
947 pkt->tidsm =
948 (struct qib_tid_session_member *)tidsm;
949 pkt->tidsmcount = tidsmsize/
950 sizeof(struct qib_tid_session_member);
951 pkt->tidsmidx = 0;
952 idx++;
956 * pbc 'fill1' field is borrowed to pass frag size,
957 * we need to clear it after picking frag size, the
958 * hardware requires this field to be zero.
960 *pbc = cpu_to_le32(le32_to_cpu(*pbc) & 0x0000FFFF);
961 } else {
962 pkt = kmem_cache_alloc(pq->pkt_slab, GFP_KERNEL);
963 if (!pkt) {
964 ret = -ENOMEM;
965 goto free_pbc;
967 pkt->largepkt = 0;
968 pkt->frag_size = bytes_togo;
969 pkt->addrlimit = ARRAY_SIZE(pkt->addr);
971 pkt->bytes_togo = bytes_togo;
972 pkt->payload_size = 0;
973 pkt->counter = counter;
974 pkt->tiddma = tiddma;
976 /* setup the first header */
977 qib_user_sdma_init_frag(pkt, 0, /* index */
978 0, len, /* offset, len */
979 1, 0, /* first last desc */
980 0, 0, /* put page, dma mapped */
981 NULL, pbc, /* struct page, virt addr */
982 dma_addr, len); /* dma addr, dma length */
983 pkt->index = 0;
984 pkt->naddr = 1;
986 if (nfrags) {
987 ret = qib_user_sdma_init_payload(dd, pq, pkt,
988 iov + idx_save + 1,
989 nfrags, npages);
990 if (ret < 0)
991 goto free_pkt;
992 } else {
993 /* since there is no payload, mark the
994 * header as the last desc. */
995 pkt->addr[0].last_desc = 1;
997 if (dma_addr == 0) {
999 * the header is not dma mapped yet.
1000 * it should be from kmalloc.
1002 dma_addr = dma_map_single(&dd->pcidev->dev,
1003 pbc, len, DMA_TO_DEVICE);
1004 if (dma_mapping_error(&dd->pcidev->dev,
1005 dma_addr)) {
1006 ret = -ENOMEM;
1007 goto free_pkt;
1009 pkt->addr[0].addr = dma_addr;
1010 pkt->addr[0].dma_mapped = 1;
1014 counter++;
1015 npkts++;
1016 pkt->pq = pq;
1017 pkt->index = 0; /* reset index for push on hw */
1018 *ndesc += pkt->naddr;
1020 list_add_tail(&pkt->list, list);
1023 *maxpkts = npkts;
1024 ret = idx;
1025 goto done;
1027 free_pkt:
1028 if (pkt->largepkt)
1029 kfree(pkt);
1030 else
1031 kmem_cache_free(pq->pkt_slab, pkt);
1032 free_pbc:
1033 if (dma_addr)
1034 dma_pool_free(pq->header_cache, pbc, dma_addr);
1035 else
1036 kfree(pbc);
1037 free_list:
1038 qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, list);
1039 done:
1040 return ret;
1043 static void qib_user_sdma_set_complete_counter(struct qib_user_sdma_queue *pq,
1044 u32 c)
1046 pq->sent_counter = c;
1049 /* try to clean out queue -- needs pq->lock */
1050 static int qib_user_sdma_queue_clean(struct qib_pportdata *ppd,
1051 struct qib_user_sdma_queue *pq)
1053 struct qib_devdata *dd = ppd->dd;
1054 struct list_head free_list;
1055 struct qib_user_sdma_pkt *pkt;
1056 struct qib_user_sdma_pkt *pkt_prev;
1057 unsigned long flags;
1058 int ret = 0;
1060 if (!pq->num_sending)
1061 return 0;
1063 INIT_LIST_HEAD(&free_list);
1066 * We need this spin lock here because interrupt handler
1067 * might modify this list in qib_user_sdma_send_desc(), also
1068 * we can not get interrupted, otherwise it is a deadlock.
1070 spin_lock_irqsave(&pq->sent_lock, flags);
1071 list_for_each_entry_safe(pkt, pkt_prev, &pq->sent, list) {
1072 s64 descd = ppd->sdma_descq_removed - pkt->added;
1074 if (descd < 0)
1075 break;
1077 list_move_tail(&pkt->list, &free_list);
1079 /* one more packet cleaned */
1080 ret++;
1081 pq->num_sending--;
1083 spin_unlock_irqrestore(&pq->sent_lock, flags);
1085 if (!list_empty(&free_list)) {
1086 u32 counter;
1088 pkt = list_entry(free_list.prev,
1089 struct qib_user_sdma_pkt, list);
1090 counter = pkt->counter;
1092 qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &free_list);
1093 qib_user_sdma_set_complete_counter(pq, counter);
1096 return ret;
1099 void qib_user_sdma_queue_destroy(struct qib_user_sdma_queue *pq)
1101 if (!pq)
1102 return;
1104 pq->sdma_rb_node->refcount--;
1105 if (pq->sdma_rb_node->refcount == 0) {
1106 rb_erase(&pq->sdma_rb_node->node, &qib_user_sdma_rb_root);
1107 kfree(pq->sdma_rb_node);
1109 dma_pool_destroy(pq->header_cache);
1110 kmem_cache_destroy(pq->pkt_slab);
1111 kfree(pq);
1114 /* clean descriptor queue, returns > 0 if some elements cleaned */
1115 static int qib_user_sdma_hwqueue_clean(struct qib_pportdata *ppd)
1117 int ret;
1118 unsigned long flags;
1120 spin_lock_irqsave(&ppd->sdma_lock, flags);
1121 ret = qib_sdma_make_progress(ppd);
1122 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1124 return ret;
1127 /* we're in close, drain packets so that we can cleanup successfully... */
1128 void qib_user_sdma_queue_drain(struct qib_pportdata *ppd,
1129 struct qib_user_sdma_queue *pq)
1131 struct qib_devdata *dd = ppd->dd;
1132 unsigned long flags;
1133 int i;
1135 if (!pq)
1136 return;
1138 for (i = 0; i < QIB_USER_SDMA_DRAIN_TIMEOUT; i++) {
1139 mutex_lock(&pq->lock);
1140 if (!pq->num_pending && !pq->num_sending) {
1141 mutex_unlock(&pq->lock);
1142 break;
1144 qib_user_sdma_hwqueue_clean(ppd);
1145 qib_user_sdma_queue_clean(ppd, pq);
1146 mutex_unlock(&pq->lock);
1147 msleep(20);
1150 if (pq->num_pending || pq->num_sending) {
1151 struct qib_user_sdma_pkt *pkt;
1152 struct qib_user_sdma_pkt *pkt_prev;
1153 struct list_head free_list;
1155 mutex_lock(&pq->lock);
1156 spin_lock_irqsave(&ppd->sdma_lock, flags);
1158 * Since we hold sdma_lock, it is safe without sent_lock.
1160 if (pq->num_pending) {
1161 list_for_each_entry_safe(pkt, pkt_prev,
1162 &ppd->sdma_userpending, list) {
1163 if (pkt->pq == pq) {
1164 list_move_tail(&pkt->list, &pq->sent);
1165 pq->num_pending--;
1166 pq->num_sending++;
1170 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1172 qib_dev_err(dd, "user sdma lists not empty: forcing!\n");
1173 INIT_LIST_HEAD(&free_list);
1174 list_splice_init(&pq->sent, &free_list);
1175 pq->num_sending = 0;
1176 qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &free_list);
1177 mutex_unlock(&pq->lock);
1181 static inline __le64 qib_sdma_make_desc0(u8 gen,
1182 u64 addr, u64 dwlen, u64 dwoffset)
1184 return cpu_to_le64(/* SDmaPhyAddr[31:0] */
1185 ((addr & 0xfffffffcULL) << 32) |
1186 /* SDmaGeneration[1:0] */
1187 ((gen & 3ULL) << 30) |
1188 /* SDmaDwordCount[10:0] */
1189 ((dwlen & 0x7ffULL) << 16) |
1190 /* SDmaBufOffset[12:2] */
1191 (dwoffset & 0x7ffULL));
1194 static inline __le64 qib_sdma_make_first_desc0(__le64 descq)
1196 return descq | cpu_to_le64(1ULL << 12);
1199 static inline __le64 qib_sdma_make_last_desc0(__le64 descq)
1201 /* last */ /* dma head */
1202 return descq | cpu_to_le64(1ULL << 11 | 1ULL << 13);
1205 static inline __le64 qib_sdma_make_desc1(u64 addr)
1207 /* SDmaPhyAddr[47:32] */
1208 return cpu_to_le64(addr >> 32);
1211 static void qib_user_sdma_send_frag(struct qib_pportdata *ppd,
1212 struct qib_user_sdma_pkt *pkt, int idx,
1213 unsigned ofs, u16 tail, u8 gen)
1215 const u64 addr = (u64) pkt->addr[idx].addr +
1216 (u64) pkt->addr[idx].offset;
1217 const u64 dwlen = (u64) pkt->addr[idx].length / 4;
1218 __le64 *descqp;
1219 __le64 descq0;
1221 descqp = &ppd->sdma_descq[tail].qw[0];
1223 descq0 = qib_sdma_make_desc0(gen, addr, dwlen, ofs);
1224 if (pkt->addr[idx].first_desc)
1225 descq0 = qib_sdma_make_first_desc0(descq0);
1226 if (pkt->addr[idx].last_desc) {
1227 descq0 = qib_sdma_make_last_desc0(descq0);
1228 if (ppd->sdma_intrequest) {
1229 descq0 |= cpu_to_le64(1ULL << 15);
1230 ppd->sdma_intrequest = 0;
1234 descqp[0] = descq0;
1235 descqp[1] = qib_sdma_make_desc1(addr);
1238 void qib_user_sdma_send_desc(struct qib_pportdata *ppd,
1239 struct list_head *pktlist)
1241 struct qib_devdata *dd = ppd->dd;
1242 u16 nfree, nsent;
1243 u16 tail, tail_c;
1244 u8 gen, gen_c;
1246 nfree = qib_sdma_descq_freecnt(ppd);
1247 if (!nfree)
1248 return;
1250 retry:
1251 nsent = 0;
1252 tail_c = tail = ppd->sdma_descq_tail;
1253 gen_c = gen = ppd->sdma_generation;
1254 while (!list_empty(pktlist)) {
1255 struct qib_user_sdma_pkt *pkt =
1256 list_entry(pktlist->next, struct qib_user_sdma_pkt,
1257 list);
1258 int i, j, c = 0;
1259 unsigned ofs = 0;
1260 u16 dtail = tail;
1262 for (i = pkt->index; i < pkt->naddr && nfree; i++) {
1263 qib_user_sdma_send_frag(ppd, pkt, i, ofs, tail, gen);
1264 ofs += pkt->addr[i].length >> 2;
1266 if (++tail == ppd->sdma_descq_cnt) {
1267 tail = 0;
1268 ++gen;
1269 ppd->sdma_intrequest = 1;
1270 } else if (tail == (ppd->sdma_descq_cnt>>1)) {
1271 ppd->sdma_intrequest = 1;
1273 nfree--;
1274 if (pkt->addr[i].last_desc == 0)
1275 continue;
1278 * If the packet is >= 2KB mtu equivalent, we
1279 * have to use the large buffers, and have to
1280 * mark each descriptor as part of a large
1281 * buffer packet.
1283 if (ofs > dd->piosize2kmax_dwords) {
1284 for (j = pkt->index; j <= i; j++) {
1285 ppd->sdma_descq[dtail].qw[0] |=
1286 cpu_to_le64(1ULL << 14);
1287 if (++dtail == ppd->sdma_descq_cnt)
1288 dtail = 0;
1291 c += i + 1 - pkt->index;
1292 pkt->index = i + 1; /* index for next first */
1293 tail_c = dtail = tail;
1294 gen_c = gen;
1295 ofs = 0; /* reset for next packet */
1298 ppd->sdma_descq_added += c;
1299 nsent += c;
1300 if (pkt->index == pkt->naddr) {
1301 pkt->added = ppd->sdma_descq_added;
1302 pkt->pq->added = pkt->added;
1303 pkt->pq->num_pending--;
1304 spin_lock(&pkt->pq->sent_lock);
1305 pkt->pq->num_sending++;
1306 list_move_tail(&pkt->list, &pkt->pq->sent);
1307 spin_unlock(&pkt->pq->sent_lock);
1309 if (!nfree || (nsent<<2) > ppd->sdma_descq_cnt)
1310 break;
1313 /* advance the tail on the chip if necessary */
1314 if (ppd->sdma_descq_tail != tail_c) {
1315 ppd->sdma_generation = gen_c;
1316 dd->f_sdma_update_tail(ppd, tail_c);
1319 if (nfree && !list_empty(pktlist))
1320 goto retry;
1323 /* pq->lock must be held, get packets on the wire... */
1324 static int qib_user_sdma_push_pkts(struct qib_pportdata *ppd,
1325 struct qib_user_sdma_queue *pq,
1326 struct list_head *pktlist, int count)
1328 unsigned long flags;
1330 if (unlikely(!(ppd->lflags & QIBL_LINKACTIVE)))
1331 return -ECOMM;
1333 /* non-blocking mode */
1334 if (pq->sdma_rb_node->refcount > 1) {
1335 spin_lock_irqsave(&ppd->sdma_lock, flags);
1336 if (unlikely(!__qib_sdma_running(ppd))) {
1337 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1338 return -ECOMM;
1340 pq->num_pending += count;
1341 list_splice_tail_init(pktlist, &ppd->sdma_userpending);
1342 qib_user_sdma_send_desc(ppd, &ppd->sdma_userpending);
1343 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1344 return 0;
1347 /* In this case, descriptors from this process are not
1348 * linked to ppd pending queue, interrupt handler
1349 * won't update this process, it is OK to directly
1350 * modify without sdma lock.
1354 pq->num_pending += count;
1356 * Blocking mode for single rail process, we must
1357 * release/regain sdma_lock to give other process
1358 * chance to make progress. This is important for
1359 * performance.
1361 do {
1362 spin_lock_irqsave(&ppd->sdma_lock, flags);
1363 if (unlikely(!__qib_sdma_running(ppd))) {
1364 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1365 return -ECOMM;
1367 qib_user_sdma_send_desc(ppd, pktlist);
1368 if (!list_empty(pktlist))
1369 qib_sdma_make_progress(ppd);
1370 spin_unlock_irqrestore(&ppd->sdma_lock, flags);
1371 } while (!list_empty(pktlist));
1373 return 0;
1376 int qib_user_sdma_writev(struct qib_ctxtdata *rcd,
1377 struct qib_user_sdma_queue *pq,
1378 const struct iovec *iov,
1379 unsigned long dim)
1381 struct qib_devdata *dd = rcd->dd;
1382 struct qib_pportdata *ppd = rcd->ppd;
1383 int ret = 0;
1384 struct list_head list;
1385 int npkts = 0;
1387 INIT_LIST_HEAD(&list);
1389 mutex_lock(&pq->lock);
1391 /* why not -ECOMM like qib_user_sdma_push_pkts() below? */
1392 if (!qib_sdma_running(ppd))
1393 goto done_unlock;
1395 /* if I have packets not complete yet */
1396 if (pq->added > ppd->sdma_descq_removed)
1397 qib_user_sdma_hwqueue_clean(ppd);
1398 /* if I have complete packets to be freed */
1399 if (pq->num_sending)
1400 qib_user_sdma_queue_clean(ppd, pq);
1402 while (dim) {
1403 int mxp = 1;
1404 int ndesc = 0;
1406 ret = qib_user_sdma_queue_pkts(dd, ppd, pq,
1407 iov, dim, &list, &mxp, &ndesc);
1408 if (ret < 0)
1409 goto done_unlock;
1410 else {
1411 dim -= ret;
1412 iov += ret;
1415 /* force packets onto the sdma hw queue... */
1416 if (!list_empty(&list)) {
1418 * Lazily clean hw queue.
1420 if (qib_sdma_descq_freecnt(ppd) < ndesc) {
1421 qib_user_sdma_hwqueue_clean(ppd);
1422 if (pq->num_sending)
1423 qib_user_sdma_queue_clean(ppd, pq);
1426 ret = qib_user_sdma_push_pkts(ppd, pq, &list, mxp);
1427 if (ret < 0)
1428 goto done_unlock;
1429 else {
1430 npkts += mxp;
1431 pq->counter += mxp;
1436 done_unlock:
1437 if (!list_empty(&list))
1438 qib_user_sdma_free_pkt_list(&dd->pcidev->dev, pq, &list);
1439 mutex_unlock(&pq->lock);
1441 return (ret < 0) ? ret : npkts;
1444 int qib_user_sdma_make_progress(struct qib_pportdata *ppd,
1445 struct qib_user_sdma_queue *pq)
1447 int ret = 0;
1449 mutex_lock(&pq->lock);
1450 qib_user_sdma_hwqueue_clean(ppd);
1451 ret = qib_user_sdma_queue_clean(ppd, pq);
1452 mutex_unlock(&pq->lock);
1454 return ret;
1457 u32 qib_user_sdma_complete_counter(const struct qib_user_sdma_queue *pq)
1459 return pq ? pq->sent_counter : 0;
1462 u32 qib_user_sdma_inflight_counter(struct qib_user_sdma_queue *pq)
1464 return pq ? pq->counter : 0;