blob: 1929cb8f17d78f2c6adc601b8e55a8d45072b33d [file] [log] [blame]
Andy Grovereff5f532009-02-24 15:30:29 +00001/*
2 * Copyright (c) 2007 Oracle. 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 */
33#include <linux/pagemap.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090034#include <linux/slab.h>
Andy Grovereff5f532009-02-24 15:30:29 +000035#include <linux/rbtree.h>
36#include <linux/dma-mapping.h> /* for DMA_*_DEVICE */
37
Andy Grover21f79af2010-01-12 12:57:27 -080038#include "rds.h"
Andy Grovereff5f532009-02-24 15:30:29 +000039
40/*
41 * XXX
42 * - build with sparse
43 * - should we limit the size of a mr region? let transport return failure?
44 * - should we detect duplicate keys on a socket? hmm.
45 * - an rdma is an mlock, apply rlimit?
46 */
47
48/*
49 * get the number of pages by looking at the page indices that the start and
50 * end addresses fall in.
51 *
52 * Returns 0 if the vec is invalid. It is invalid if the number of bytes
53 * causes the address to wrap or overflows an unsigned int. This comes
54 * from being stored in the 'length' member of 'struct scatterlist'.
55 */
56static unsigned int rds_pages_in_vec(struct rds_iovec *vec)
57{
58 if ((vec->addr + vec->bytes <= vec->addr) ||
59 (vec->bytes > (u64)UINT_MAX))
60 return 0;
61
62 return ((vec->addr + vec->bytes + PAGE_SIZE - 1) >> PAGE_SHIFT) -
63 (vec->addr >> PAGE_SHIFT);
64}
65
66static struct rds_mr *rds_mr_tree_walk(struct rb_root *root, u64 key,
67 struct rds_mr *insert)
68{
69 struct rb_node **p = &root->rb_node;
70 struct rb_node *parent = NULL;
71 struct rds_mr *mr;
72
73 while (*p) {
74 parent = *p;
75 mr = rb_entry(parent, struct rds_mr, r_rb_node);
76
77 if (key < mr->r_key)
78 p = &(*p)->rb_left;
79 else if (key > mr->r_key)
80 p = &(*p)->rb_right;
81 else
82 return mr;
83 }
84
85 if (insert) {
86 rb_link_node(&insert->r_rb_node, parent, p);
87 rb_insert_color(&insert->r_rb_node, root);
88 atomic_inc(&insert->r_refcount);
89 }
90 return NULL;
91}
92
93/*
94 * Destroy the transport-specific part of a MR.
95 */
96static void rds_destroy_mr(struct rds_mr *mr)
97{
98 struct rds_sock *rs = mr->r_sock;
99 void *trans_private = NULL;
100 unsigned long flags;
101
102 rdsdebug("RDS: destroy mr key is %x refcnt %u\n",
103 mr->r_key, atomic_read(&mr->r_refcount));
104
105 if (test_and_set_bit(RDS_MR_DEAD, &mr->r_state))
106 return;
107
108 spin_lock_irqsave(&rs->rs_rdma_lock, flags);
109 if (!RB_EMPTY_NODE(&mr->r_rb_node))
110 rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys);
111 trans_private = mr->r_trans_private;
112 mr->r_trans_private = NULL;
113 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags);
114
115 if (trans_private)
116 mr->r_trans->free_mr(trans_private, mr->r_invalidate);
117}
118
119void __rds_put_mr_final(struct rds_mr *mr)
120{
121 rds_destroy_mr(mr);
122 kfree(mr);
123}
124
125/*
126 * By the time this is called we can't have any more ioctls called on
127 * the socket so we don't need to worry about racing with others.
128 */
129void rds_rdma_drop_keys(struct rds_sock *rs)
130{
131 struct rds_mr *mr;
132 struct rb_node *node;
Tina Yang35b52c72010-04-01 14:09:00 -0700133 unsigned long flags;
Andy Grovereff5f532009-02-24 15:30:29 +0000134
135 /* Release any MRs associated with this socket */
Tina Yang35b52c72010-04-01 14:09:00 -0700136 spin_lock_irqsave(&rs->rs_rdma_lock, flags);
Andy Grovereff5f532009-02-24 15:30:29 +0000137 while ((node = rb_first(&rs->rs_rdma_keys))) {
138 mr = container_of(node, struct rds_mr, r_rb_node);
139 if (mr->r_trans == rs->rs_transport)
140 mr->r_invalidate = 0;
Tina Yang35b52c72010-04-01 14:09:00 -0700141 rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys);
142 RB_CLEAR_NODE(&mr->r_rb_node);
143 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags);
144 rds_destroy_mr(mr);
Andy Grovereff5f532009-02-24 15:30:29 +0000145 rds_mr_put(mr);
Tina Yang35b52c72010-04-01 14:09:00 -0700146 spin_lock_irqsave(&rs->rs_rdma_lock, flags);
Andy Grovereff5f532009-02-24 15:30:29 +0000147 }
Tina Yang35b52c72010-04-01 14:09:00 -0700148 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags);
Andy Grovereff5f532009-02-24 15:30:29 +0000149
150 if (rs->rs_transport && rs->rs_transport->flush_mrs)
151 rs->rs_transport->flush_mrs();
152}
153
154/*
155 * Helper function to pin user pages.
156 */
157static int rds_pin_pages(unsigned long user_addr, unsigned int nr_pages,
158 struct page **pages, int write)
159{
160 int ret;
161
Andy Grover830eb7d2009-04-09 14:09:42 +0000162 ret = get_user_pages_fast(user_addr, nr_pages, write, pages);
Andy Grovereff5f532009-02-24 15:30:29 +0000163
Andy Grover7acd4a72009-04-09 14:09:40 +0000164 if (ret >= 0 && ret < nr_pages) {
Andy Grovereff5f532009-02-24 15:30:29 +0000165 while (ret--)
166 put_page(pages[ret]);
167 ret = -EFAULT;
168 }
169
170 return ret;
171}
172
173static int __rds_rdma_map(struct rds_sock *rs, struct rds_get_mr_args *args,
174 u64 *cookie_ret, struct rds_mr **mr_ret)
175{
176 struct rds_mr *mr = NULL, *found;
177 unsigned int nr_pages;
178 struct page **pages = NULL;
179 struct scatterlist *sg;
180 void *trans_private;
181 unsigned long flags;
182 rds_rdma_cookie_t cookie;
183 unsigned int nents;
184 long i;
185 int ret;
186
187 if (rs->rs_bound_addr == 0) {
188 ret = -ENOTCONN; /* XXX not a great errno */
189 goto out;
190 }
191
Andy Grover8690bfa2010-01-12 11:56:44 -0800192 if (!rs->rs_transport->get_mr) {
Andy Grovereff5f532009-02-24 15:30:29 +0000193 ret = -EOPNOTSUPP;
194 goto out;
195 }
196
197 nr_pages = rds_pages_in_vec(&args->vec);
198 if (nr_pages == 0) {
199 ret = -EINVAL;
200 goto out;
201 }
202
203 rdsdebug("RDS: get_mr addr %llx len %llu nr_pages %u\n",
204 args->vec.addr, args->vec.bytes, nr_pages);
205
206 /* XXX clamp nr_pages to limit the size of this alloc? */
207 pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL);
Andy Grover8690bfa2010-01-12 11:56:44 -0800208 if (!pages) {
Andy Grovereff5f532009-02-24 15:30:29 +0000209 ret = -ENOMEM;
210 goto out;
211 }
212
213 mr = kzalloc(sizeof(struct rds_mr), GFP_KERNEL);
Andy Grover8690bfa2010-01-12 11:56:44 -0800214 if (!mr) {
Andy Grovereff5f532009-02-24 15:30:29 +0000215 ret = -ENOMEM;
216 goto out;
217 }
218
219 atomic_set(&mr->r_refcount, 1);
220 RB_CLEAR_NODE(&mr->r_rb_node);
221 mr->r_trans = rs->rs_transport;
222 mr->r_sock = rs;
223
224 if (args->flags & RDS_RDMA_USE_ONCE)
225 mr->r_use_once = 1;
226 if (args->flags & RDS_RDMA_INVALIDATE)
227 mr->r_invalidate = 1;
228 if (args->flags & RDS_RDMA_READWRITE)
229 mr->r_write = 1;
230
231 /*
232 * Pin the pages that make up the user buffer and transfer the page
233 * pointers to the mr's sg array. We check to see if we've mapped
234 * the whole region after transferring the partial page references
235 * to the sg array so that we can have one page ref cleanup path.
236 *
237 * For now we have no flag that tells us whether the mapping is
238 * r/o or r/w. We need to assume r/w, or we'll do a lot of RDMA to
239 * the zero page.
240 */
Andy Groverd22faec2010-01-12 10:52:28 -0800241 ret = rds_pin_pages(args->vec.addr, nr_pages, pages, 1);
Andy Grovereff5f532009-02-24 15:30:29 +0000242 if (ret < 0)
243 goto out;
244
245 nents = ret;
246 sg = kcalloc(nents, sizeof(*sg), GFP_KERNEL);
Andy Grover8690bfa2010-01-12 11:56:44 -0800247 if (!sg) {
Andy Grovereff5f532009-02-24 15:30:29 +0000248 ret = -ENOMEM;
249 goto out;
250 }
251 WARN_ON(!nents);
252 sg_init_table(sg, nents);
253
254 /* Stick all pages into the scatterlist */
255 for (i = 0 ; i < nents; i++)
256 sg_set_page(&sg[i], pages[i], PAGE_SIZE, 0);
257
258 rdsdebug("RDS: trans_private nents is %u\n", nents);
259
260 /* Obtain a transport specific MR. If this succeeds, the
261 * s/g list is now owned by the MR.
262 * Note that dma_map() implies that pending writes are
263 * flushed to RAM, so no dma_sync is needed here. */
264 trans_private = rs->rs_transport->get_mr(sg, nents, rs,
265 &mr->r_key);
266
267 if (IS_ERR(trans_private)) {
268 for (i = 0 ; i < nents; i++)
269 put_page(sg_page(&sg[i]));
270 kfree(sg);
271 ret = PTR_ERR(trans_private);
272 goto out;
273 }
274
275 mr->r_trans_private = trans_private;
276
277 rdsdebug("RDS: get_mr put_user key is %x cookie_addr %p\n",
278 mr->r_key, (void *)(unsigned long) args->cookie_addr);
279
280 /* The user may pass us an unaligned address, but we can only
281 * map page aligned regions. So we keep the offset, and build
282 * a 64bit cookie containing <R_Key, offset> and pass that
283 * around. */
284 cookie = rds_rdma_make_cookie(mr->r_key, args->vec.addr & ~PAGE_MASK);
285 if (cookie_ret)
286 *cookie_ret = cookie;
287
288 if (args->cookie_addr && put_user(cookie, (u64 __user *)(unsigned long) args->cookie_addr)) {
289 ret = -EFAULT;
290 goto out;
291 }
292
293 /* Inserting the new MR into the rbtree bumps its
294 * reference count. */
295 spin_lock_irqsave(&rs->rs_rdma_lock, flags);
296 found = rds_mr_tree_walk(&rs->rs_rdma_keys, mr->r_key, mr);
297 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags);
298
299 BUG_ON(found && found != mr);
300
301 rdsdebug("RDS: get_mr key is %x\n", mr->r_key);
302 if (mr_ret) {
303 atomic_inc(&mr->r_refcount);
304 *mr_ret = mr;
305 }
306
307 ret = 0;
308out:
309 kfree(pages);
310 if (mr)
311 rds_mr_put(mr);
312 return ret;
313}
314
315int rds_get_mr(struct rds_sock *rs, char __user *optval, int optlen)
316{
317 struct rds_get_mr_args args;
318
319 if (optlen != sizeof(struct rds_get_mr_args))
320 return -EINVAL;
321
322 if (copy_from_user(&args, (struct rds_get_mr_args __user *)optval,
323 sizeof(struct rds_get_mr_args)))
324 return -EFAULT;
325
326 return __rds_rdma_map(rs, &args, NULL, NULL);
327}
328
Andy Grover244546f2009-10-30 08:54:53 +0000329int rds_get_mr_for_dest(struct rds_sock *rs, char __user *optval, int optlen)
330{
331 struct rds_get_mr_for_dest_args args;
332 struct rds_get_mr_args new_args;
333
334 if (optlen != sizeof(struct rds_get_mr_for_dest_args))
335 return -EINVAL;
336
337 if (copy_from_user(&args, (struct rds_get_mr_for_dest_args __user *)optval,
338 sizeof(struct rds_get_mr_for_dest_args)))
339 return -EFAULT;
340
341 /*
342 * Initially, just behave like get_mr().
343 * TODO: Implement get_mr as wrapper around this
344 * and deprecate it.
345 */
346 new_args.vec = args.vec;
347 new_args.cookie_addr = args.cookie_addr;
348 new_args.flags = args.flags;
349
350 return __rds_rdma_map(rs, &new_args, NULL, NULL);
351}
352
Andy Grovereff5f532009-02-24 15:30:29 +0000353/*
354 * Free the MR indicated by the given R_Key
355 */
356int rds_free_mr(struct rds_sock *rs, char __user *optval, int optlen)
357{
358 struct rds_free_mr_args args;
359 struct rds_mr *mr;
360 unsigned long flags;
361
362 if (optlen != sizeof(struct rds_free_mr_args))
363 return -EINVAL;
364
365 if (copy_from_user(&args, (struct rds_free_mr_args __user *)optval,
366 sizeof(struct rds_free_mr_args)))
367 return -EFAULT;
368
369 /* Special case - a null cookie means flush all unused MRs */
370 if (args.cookie == 0) {
371 if (!rs->rs_transport || !rs->rs_transport->flush_mrs)
372 return -EINVAL;
373 rs->rs_transport->flush_mrs();
374 return 0;
375 }
376
377 /* Look up the MR given its R_key and remove it from the rbtree
378 * so nobody else finds it.
379 * This should also prevent races with rds_rdma_unuse.
380 */
381 spin_lock_irqsave(&rs->rs_rdma_lock, flags);
382 mr = rds_mr_tree_walk(&rs->rs_rdma_keys, rds_rdma_cookie_key(args.cookie), NULL);
383 if (mr) {
384 rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys);
385 RB_CLEAR_NODE(&mr->r_rb_node);
386 if (args.flags & RDS_RDMA_INVALIDATE)
387 mr->r_invalidate = 1;
388 }
389 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags);
390
391 if (!mr)
392 return -EINVAL;
393
394 /*
395 * call rds_destroy_mr() ourselves so that we're sure it's done by the time
396 * we return. If we let rds_mr_put() do it it might not happen until
397 * someone else drops their ref.
398 */
399 rds_destroy_mr(mr);
400 rds_mr_put(mr);
401 return 0;
402}
403
404/*
405 * This is called when we receive an extension header that
406 * tells us this MR was used. It allows us to implement
407 * use_once semantics
408 */
409void rds_rdma_unuse(struct rds_sock *rs, u32 r_key, int force)
410{
411 struct rds_mr *mr;
412 unsigned long flags;
413 int zot_me = 0;
414
415 spin_lock_irqsave(&rs->rs_rdma_lock, flags);
416 mr = rds_mr_tree_walk(&rs->rs_rdma_keys, r_key, NULL);
Andy Grover3ef13f32010-01-12 12:37:17 -0800417 if (!mr) {
418 printk(KERN_ERR "rds: trying to unuse MR with unknown r_key %u!\n", r_key);
419 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags);
420 return;
421 }
422
423 if (mr->r_use_once || force) {
Andy Grovereff5f532009-02-24 15:30:29 +0000424 rb_erase(&mr->r_rb_node, &rs->rs_rdma_keys);
425 RB_CLEAR_NODE(&mr->r_rb_node);
426 zot_me = 1;
Andy Grover3ef13f32010-01-12 12:37:17 -0800427 }
Andy Grovereff5f532009-02-24 15:30:29 +0000428 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags);
429
430 /* May have to issue a dma_sync on this memory region.
431 * Note we could avoid this if the operation was a RDMA READ,
432 * but at this point we can't tell. */
Andy Grover3ef13f32010-01-12 12:37:17 -0800433 if (mr->r_trans->sync_mr)
434 mr->r_trans->sync_mr(mr->r_trans_private, DMA_FROM_DEVICE);
Andy Grovereff5f532009-02-24 15:30:29 +0000435
Andy Grover3ef13f32010-01-12 12:37:17 -0800436 /* If the MR was marked as invalidate, this will
437 * trigger an async flush. */
438 if (zot_me)
439 rds_destroy_mr(mr);
440 rds_mr_put(mr);
Andy Grovereff5f532009-02-24 15:30:29 +0000441}
442
443void rds_rdma_free_op(struct rds_rdma_op *ro)
444{
445 unsigned int i;
446
447 for (i = 0; i < ro->r_nents; i++) {
448 struct page *page = sg_page(&ro->r_sg[i]);
449
450 /* Mark page dirty if it was possibly modified, which
451 * is the case for a RDMA_READ which copies from remote
452 * to local memory */
Andy Grover561c7df2010-03-11 13:50:06 +0000453 if (!ro->r_write) {
Andy Grover9e2effb2010-03-12 16:22:32 -0800454 BUG_ON(irqs_disabled());
Andy Grovereff5f532009-02-24 15:30:29 +0000455 set_page_dirty(page);
Andy Grover561c7df2010-03-11 13:50:06 +0000456 }
Andy Grovereff5f532009-02-24 15:30:29 +0000457 put_page(page);
458 }
459
460 kfree(ro->r_notifier);
Andy Groverff87e972010-01-12 14:13:15 -0800461 ro->r_notifier = NULL;
462 ro->r_active = 0;
463}
464
465/*
466 * Count the number of pages needed to describe an incoming iovec.
467 */
468static int rds_rdma_pages(struct rds_rdma_args *args)
469{
470 struct rds_iovec vec;
471 struct rds_iovec __user *local_vec;
472 unsigned int tot_pages = 0;
473 unsigned int nr_pages;
474 unsigned int i;
475
476 local_vec = (struct rds_iovec __user *)(unsigned long) args->local_vec_addr;
477
478 /* figure out the number of pages in the vector */
479 for (i = 0; i < args->nr_local; i++) {
480 if (copy_from_user(&vec, &local_vec[i],
481 sizeof(struct rds_iovec)))
482 return -EFAULT;
483
484 nr_pages = rds_pages_in_vec(&vec);
485 if (nr_pages == 0)
486 return -EINVAL;
487
488 tot_pages += nr_pages;
489 }
490
491 return tot_pages;
492}
493
494int rds_rdma_extra_size(struct rds_rdma_args *args)
495{
496 return rds_rdma_pages(args) * sizeof(struct scatterlist);
Andy Grovereff5f532009-02-24 15:30:29 +0000497}
498
499/*
500 * args is a pointer to an in-kernel copy in the sendmsg cmsg.
501 */
Andy Groverff87e972010-01-12 14:13:15 -0800502static int rds_rdma_prepare(struct rds_message *rm,
503 struct rds_sock *rs,
504 struct rds_rdma_args *args)
Andy Grovereff5f532009-02-24 15:30:29 +0000505{
506 struct rds_iovec vec;
Andy Groverff87e972010-01-12 14:13:15 -0800507 struct rds_rdma_op *op = &rm->rdma.m_rdma_op;
Andy Grovereff5f532009-02-24 15:30:29 +0000508 unsigned int nr_pages;
Andy Grovereff5f532009-02-24 15:30:29 +0000509 unsigned int nr_bytes;
510 struct page **pages = NULL;
511 struct rds_iovec __user *local_vec;
Andy Grovereff5f532009-02-24 15:30:29 +0000512 unsigned int nr;
513 unsigned int i, j;
Andy Groverff87e972010-01-12 14:13:15 -0800514 int ret = 0;
Andy Grovereff5f532009-02-24 15:30:29 +0000515
516
517 if (rs->rs_bound_addr == 0) {
518 ret = -ENOTCONN; /* XXX not a great errno */
519 goto out;
520 }
521
522 if (args->nr_local > (u64)UINT_MAX) {
523 ret = -EMSGSIZE;
524 goto out;
525 }
526
Andy Groverff87e972010-01-12 14:13:15 -0800527 nr_pages = rds_rdma_pages(args);
528 if (nr_pages < 0)
529 goto out;
Andy Grovereff5f532009-02-24 15:30:29 +0000530
Andy Groverff87e972010-01-12 14:13:15 -0800531 pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL);
Andy Grover8690bfa2010-01-12 11:56:44 -0800532 if (!pages) {
Andy Grovereff5f532009-02-24 15:30:29 +0000533 ret = -ENOMEM;
534 goto out;
535 }
536
Andy Grovereff5f532009-02-24 15:30:29 +0000537 op->r_write = !!(args->flags & RDS_RDMA_READWRITE);
538 op->r_fence = !!(args->flags & RDS_RDMA_FENCE);
539 op->r_notify = !!(args->flags & RDS_RDMA_NOTIFY_ME);
Andy Groverff87e972010-01-12 14:13:15 -0800540 op->r_active = 1;
Andy Grovereff5f532009-02-24 15:30:29 +0000541 op->r_recverr = rs->rs_recverr;
542 WARN_ON(!nr_pages);
Andy Groverf4dd96f72010-01-12 14:17:31 -0800543 op->r_sg = rds_message_alloc_sgs(rm, nr_pages);
Andy Grovereff5f532009-02-24 15:30:29 +0000544
545 if (op->r_notify || op->r_recverr) {
546 /* We allocate an uninitialized notifier here, because
547 * we don't want to do that in the completion handler. We
548 * would have to use GFP_ATOMIC there, and don't want to deal
549 * with failed allocations.
550 */
551 op->r_notifier = kmalloc(sizeof(struct rds_notifier), GFP_KERNEL);
552 if (!op->r_notifier) {
553 ret = -ENOMEM;
554 goto out;
555 }
556 op->r_notifier->n_user_token = args->user_token;
557 op->r_notifier->n_status = RDS_RDMA_SUCCESS;
558 }
559
560 /* The cookie contains the R_Key of the remote memory region, and
561 * optionally an offset into it. This is how we implement RDMA into
562 * unaligned memory.
563 * When setting up the RDMA, we need to add that offset to the
564 * destination address (which is really an offset into the MR)
565 * FIXME: We may want to move this into ib_rdma.c
566 */
567 op->r_key = rds_rdma_cookie_key(args->cookie);
568 op->r_remote_addr = args->remote_vec.addr + rds_rdma_cookie_offset(args->cookie);
569
570 nr_bytes = 0;
571
572 rdsdebug("RDS: rdma prepare nr_local %llu rva %llx rkey %x\n",
573 (unsigned long long)args->nr_local,
574 (unsigned long long)args->remote_vec.addr,
575 op->r_key);
576
Andy Groverff87e972010-01-12 14:13:15 -0800577 local_vec = (struct rds_iovec __user *)(unsigned long) args->local_vec_addr;
578
Andy Grovereff5f532009-02-24 15:30:29 +0000579 for (i = 0; i < args->nr_local; i++) {
580 if (copy_from_user(&vec, &local_vec[i],
581 sizeof(struct rds_iovec))) {
582 ret = -EFAULT;
583 goto out;
584 }
585
586 nr = rds_pages_in_vec(&vec);
587 if (nr == 0) {
588 ret = -EINVAL;
589 goto out;
590 }
591
592 rs->rs_user_addr = vec.addr;
593 rs->rs_user_bytes = vec.bytes;
594
Andy Grovereff5f532009-02-24 15:30:29 +0000595 /* If it's a WRITE operation, we want to pin the pages for reading.
596 * If it's a READ operation, we need to pin the pages for writing.
597 */
Andy Groverd22faec2010-01-12 10:52:28 -0800598 ret = rds_pin_pages(vec.addr, nr, pages, !op->r_write);
Andy Grovereff5f532009-02-24 15:30:29 +0000599 if (ret < 0)
600 goto out;
601
602 rdsdebug("RDS: nr_bytes %u nr %u vec.bytes %llu vec.addr %llx\n",
603 nr_bytes, nr, vec.bytes, vec.addr);
604
605 nr_bytes += vec.bytes;
606
607 for (j = 0; j < nr; j++) {
608 unsigned int offset = vec.addr & ~PAGE_MASK;
Andy Groverff87e972010-01-12 14:13:15 -0800609 struct scatterlist *sg;
Andy Grovereff5f532009-02-24 15:30:29 +0000610
611 sg = &op->r_sg[op->r_nents + j];
612 sg_set_page(sg, pages[j],
613 min_t(unsigned int, vec.bytes, PAGE_SIZE - offset),
614 offset);
615
616 rdsdebug("RDS: sg->offset %x sg->len %x vec.addr %llx vec.bytes %llu\n",
617 sg->offset, sg->length, vec.addr, vec.bytes);
618
619 vec.addr += sg->length;
620 vec.bytes -= sg->length;
621 }
622
623 op->r_nents += nr;
624 }
625
626
627 if (nr_bytes > args->remote_vec.bytes) {
628 rdsdebug("RDS nr_bytes %u remote_bytes %u do not match\n",
629 nr_bytes,
630 (unsigned int) args->remote_vec.bytes);
631 ret = -EINVAL;
632 goto out;
633 }
634 op->r_bytes = nr_bytes;
635
636 ret = 0;
637out:
638 kfree(pages);
Andy Groverff87e972010-01-12 14:13:15 -0800639 if (ret)
640 rds_rdma_free_op(op);
641
642 return ret;
Andy Grovereff5f532009-02-24 15:30:29 +0000643}
644
645/*
646 * The application asks for a RDMA transfer.
647 * Extract all arguments and set up the rdma_op
648 */
649int rds_cmsg_rdma_args(struct rds_sock *rs, struct rds_message *rm,
650 struct cmsghdr *cmsg)
651{
Andy Groverff87e972010-01-12 14:13:15 -0800652 int ret;
Andy Grovereff5f532009-02-24 15:30:29 +0000653
Joe Perchesf64f9e72009-11-29 16:55:45 -0800654 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct rds_rdma_args)) ||
Andy Groverff87e972010-01-12 14:13:15 -0800655 rm->rdma.m_rdma_op.r_active)
Andy Grovereff5f532009-02-24 15:30:29 +0000656 return -EINVAL;
657
Andy Groverff87e972010-01-12 14:13:15 -0800658 ret = rds_rdma_prepare(rm, rs, CMSG_DATA(cmsg));
659 if (ret)
660 return ret;
661
Andy Grovereff5f532009-02-24 15:30:29 +0000662 rds_stats_inc(s_send_rdma);
Andy Grovereff5f532009-02-24 15:30:29 +0000663 return 0;
664}
665
666/*
667 * The application wants us to pass an RDMA destination (aka MR)
668 * to the remote
669 */
670int rds_cmsg_rdma_dest(struct rds_sock *rs, struct rds_message *rm,
671 struct cmsghdr *cmsg)
672{
673 unsigned long flags;
674 struct rds_mr *mr;
675 u32 r_key;
676 int err = 0;
677
Joe Perchesf64f9e72009-11-29 16:55:45 -0800678 if (cmsg->cmsg_len < CMSG_LEN(sizeof(rds_rdma_cookie_t)) ||
679 rm->m_rdma_cookie != 0)
Andy Grovereff5f532009-02-24 15:30:29 +0000680 return -EINVAL;
681
682 memcpy(&rm->m_rdma_cookie, CMSG_DATA(cmsg), sizeof(rm->m_rdma_cookie));
683
684 /* We are reusing a previously mapped MR here. Most likely, the
685 * application has written to the buffer, so we need to explicitly
686 * flush those writes to RAM. Otherwise the HCA may not see them
687 * when doing a DMA from that buffer.
688 */
689 r_key = rds_rdma_cookie_key(rm->m_rdma_cookie);
690
Andy Grovere7791372010-01-12 12:15:02 -0800691
Andy Grovereff5f532009-02-24 15:30:29 +0000692 spin_lock_irqsave(&rs->rs_rdma_lock, flags);
693 mr = rds_mr_tree_walk(&rs->rs_rdma_keys, r_key, NULL);
Andy Grover8690bfa2010-01-12 11:56:44 -0800694 if (!mr)
Andy Grovereff5f532009-02-24 15:30:29 +0000695 err = -EINVAL; /* invalid r_key */
696 else
697 atomic_inc(&mr->r_refcount);
698 spin_unlock_irqrestore(&rs->rs_rdma_lock, flags);
699
700 if (mr) {
701 mr->r_trans->sync_mr(mr->r_trans_private, DMA_TO_DEVICE);
Andy Grovere7791372010-01-12 12:15:02 -0800702 rm->rdma.m_rdma_mr = mr;
Andy Grovereff5f532009-02-24 15:30:29 +0000703 }
704 return err;
705}
706
707/*
708 * The application passes us an address range it wants to enable RDMA
709 * to/from. We map the area, and save the <R_Key,offset> pair
710 * in rm->m_rdma_cookie. This causes it to be sent along to the peer
711 * in an extension header.
712 */
713int rds_cmsg_rdma_map(struct rds_sock *rs, struct rds_message *rm,
714 struct cmsghdr *cmsg)
715{
Joe Perchesf64f9e72009-11-29 16:55:45 -0800716 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct rds_get_mr_args)) ||
717 rm->m_rdma_cookie != 0)
Andy Grovereff5f532009-02-24 15:30:29 +0000718 return -EINVAL;
719
Andy Grovere7791372010-01-12 12:15:02 -0800720 return __rds_rdma_map(rs, CMSG_DATA(cmsg), &rm->m_rdma_cookie, &rm->rdma.m_rdma_mr);
Andy Grovereff5f532009-02-24 15:30:29 +0000721}
Andy Grover15133f62010-01-12 14:33:38 -0800722
723/*
724 * Fill in rds_message for an atomic request.
725 */
726int rds_cmsg_atomic(struct rds_sock *rs, struct rds_message *rm,
727 struct cmsghdr *cmsg)
728{
729 struct page *page = NULL;
730 struct rds_atomic_args *args;
731 int ret = 0;
732
733 if (cmsg->cmsg_len < CMSG_LEN(sizeof(struct rds_atomic_args))
734 || rm->atomic.op_active)
735 return -EINVAL;
736
737 args = CMSG_DATA(cmsg);
738
739 if (cmsg->cmsg_type == RDS_CMSG_ATOMIC_CSWP) {
740 rm->atomic.op_type = RDS_ATOMIC_TYPE_CSWP;
741 rm->atomic.op_swap_add = args->cswp.swap;
742 rm->atomic.op_compare = args->cswp.compare;
743 } else {
744 rm->atomic.op_type = RDS_ATOMIC_TYPE_FADD;
745 rm->atomic.op_swap_add = args->fadd.add;
746 }
747
Andy Grover15133f62010-01-12 14:33:38 -0800748 rm->atomic.op_notify = !!(args->flags & RDS_RDMA_NOTIFY_ME);
749 rm->atomic.op_recverr = rs->rs_recverr;
750 rm->atomic.op_sg = rds_message_alloc_sgs(rm, 1);
751
752 /* verify 8 byte-aligned */
753 if (args->local_addr & 0x7) {
754 ret = -EFAULT;
755 goto err;
756 }
757
758 ret = rds_pin_pages(args->local_addr, 1, &page, 1);
759 if (ret != 1)
760 goto err;
761 ret = 0;
762
763 sg_set_page(rm->atomic.op_sg, page, 8, offset_in_page(args->local_addr));
764
765 if (rm->atomic.op_notify || rm->atomic.op_recverr) {
766 /* We allocate an uninitialized notifier here, because
767 * we don't want to do that in the completion handler. We
768 * would have to use GFP_ATOMIC there, and don't want to deal
769 * with failed allocations.
770 */
771 rm->atomic.op_notifier = kmalloc(sizeof(*rm->atomic.op_notifier), GFP_KERNEL);
772 if (!rm->atomic.op_notifier) {
773 ret = -ENOMEM;
774 goto err;
775 }
776
777 rm->atomic.op_notifier->n_user_token = args->user_token;
778 rm->atomic.op_notifier->n_status = RDS_RDMA_SUCCESS;
779 }
780
Andy Grover40589e72010-01-12 10:50:48 -0800781 rm->atomic.op_rkey = rds_rdma_cookie_key(args->cookie);
Andy Grover15133f62010-01-12 14:33:38 -0800782 rm->atomic.op_remote_addr = args->remote_addr + rds_rdma_cookie_offset(args->cookie);
783
784 rm->atomic.op_active = 1;
785
786 return ret;
787err:
788 if (page)
789 put_page(page);
790 kfree(rm->atomic.op_notifier);
791
792 return ret;
793}