Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2003 Sistina Software | |
891ce207 | 3 | * Copyright (C) 2006 Red Hat GmbH |
1da177e4 LT |
4 | * |
5 | * This file is released under the GPL. | |
6 | */ | |
7 | ||
4cc96131 | 8 | #include "dm-core.h" |
952b3557 | 9 | |
586e80e6 | 10 | #include <linux/device-mapper.h> |
1da177e4 LT |
11 | |
12 | #include <linux/bio.h> | |
10f1d5d1 | 13 | #include <linux/completion.h> |
1da177e4 LT |
14 | #include <linux/mempool.h> |
15 | #include <linux/module.h> | |
16 | #include <linux/sched.h> | |
17 | #include <linux/slab.h> | |
a765e20e | 18 | #include <linux/dm-io.h> |
1da177e4 | 19 | |
f1e53987 MP |
20 | #define DM_MSG_PREFIX "io" |
21 | ||
22 | #define DM_IO_MAX_REGIONS BITS_PER_LONG | |
23 | ||
891ce207 | 24 | struct dm_io_client { |
6f1c819c KO |
25 | mempool_t pool; |
26 | struct bio_set bios; | |
891ce207 HM |
27 | }; |
28 | ||
f1e53987 MP |
29 | /* |
30 | * Aligning 'struct io' reduces the number of bits required to store | |
31 | * its address. Refer to store_io_and_region_in_bio() below. | |
32 | */ | |
1da177e4 | 33 | struct io { |
e01fd7ee | 34 | unsigned long error_bits; |
1da177e4 | 35 | atomic_t count; |
891ce207 | 36 | struct dm_io_client *client; |
1da177e4 LT |
37 | io_notify_fn callback; |
38 | void *context; | |
bb91bc7b MP |
39 | void *vma_invalidate_address; |
40 | unsigned long vma_invalidate_size; | |
f1e53987 | 41 | } __attribute__((aligned(DM_IO_MAX_REGIONS))); |
1da177e4 | 42 | |
952b3557 MP |
43 | static struct kmem_cache *_dm_io_cache; |
44 | ||
c8b03afe HM |
45 | /* |
46 | * Create a client with mempool and bioset. | |
47 | */ | |
bda8efec | 48 | struct dm_io_client *dm_io_client_create(void) |
c8b03afe | 49 | { |
c8b03afe | 50 | struct dm_io_client *client; |
e8603136 | 51 | unsigned min_ios = dm_get_reserved_bio_based_ios(); |
6f1c819c | 52 | int ret; |
c8b03afe | 53 | |
d3775354 | 54 | client = kzalloc(sizeof(*client), GFP_KERNEL); |
c8b03afe HM |
55 | if (!client) |
56 | return ERR_PTR(-ENOMEM); | |
57 | ||
6f1c819c KO |
58 | ret = mempool_init_slab_pool(&client->pool, min_ios, _dm_io_cache); |
59 | if (ret) | |
c8b03afe HM |
60 | goto bad; |
61 | ||
6f1c819c KO |
62 | ret = bioset_init(&client->bios, min_ios, 0, BIOSET_NEED_BVECS); |
63 | if (ret) | |
c8b03afe HM |
64 | goto bad; |
65 | ||
66 | return client; | |
67 | ||
68 | bad: | |
6f1c819c | 69 | mempool_exit(&client->pool); |
c8b03afe | 70 | kfree(client); |
6f1c819c | 71 | return ERR_PTR(ret); |
c8b03afe HM |
72 | } |
73 | EXPORT_SYMBOL(dm_io_client_create); | |
74 | ||
c8b03afe HM |
75 | void dm_io_client_destroy(struct dm_io_client *client) |
76 | { | |
6f1c819c KO |
77 | mempool_exit(&client->pool); |
78 | bioset_exit(&client->bios); | |
c8b03afe HM |
79 | kfree(client); |
80 | } | |
81 | EXPORT_SYMBOL(dm_io_client_destroy); | |
82 | ||
1da177e4 LT |
83 | /*----------------------------------------------------------------- |
84 | * We need to keep track of which region a bio is doing io for. | |
f1e53987 MP |
85 | * To avoid a memory allocation to store just 5 or 6 bits, we |
86 | * ensure the 'struct io' pointer is aligned so enough low bits are | |
87 | * always zero and then combine it with the region number directly in | |
88 | * bi_private. | |
1da177e4 | 89 | *---------------------------------------------------------------*/ |
f1e53987 MP |
90 | static void store_io_and_region_in_bio(struct bio *bio, struct io *io, |
91 | unsigned region) | |
1da177e4 | 92 | { |
f1e53987 MP |
93 | if (unlikely(!IS_ALIGNED((unsigned long)io, DM_IO_MAX_REGIONS))) { |
94 | DMCRIT("Unaligned struct io pointer %p", io); | |
95 | BUG(); | |
96 | } | |
97 | ||
98 | bio->bi_private = (void *)((unsigned long)io | region); | |
1da177e4 LT |
99 | } |
100 | ||
f1e53987 MP |
101 | static void retrieve_io_and_region_from_bio(struct bio *bio, struct io **io, |
102 | unsigned *region) | |
1da177e4 | 103 | { |
f1e53987 MP |
104 | unsigned long val = (unsigned long)bio->bi_private; |
105 | ||
106 | *io = (void *)(val & -(unsigned long)DM_IO_MAX_REGIONS); | |
107 | *region = val & (DM_IO_MAX_REGIONS - 1); | |
1da177e4 LT |
108 | } |
109 | ||
110 | /*----------------------------------------------------------------- | |
111 | * We need an io object to keep track of the number of bios that | |
112 | * have been dispatched for a particular io. | |
113 | *---------------------------------------------------------------*/ | |
97e7cdf1 | 114 | static void complete_io(struct io *io) |
1da177e4 | 115 | { |
97e7cdf1 JT |
116 | unsigned long error_bits = io->error_bits; |
117 | io_notify_fn fn = io->callback; | |
118 | void *context = io->context; | |
1da177e4 | 119 | |
97e7cdf1 JT |
120 | if (io->vma_invalidate_size) |
121 | invalidate_kernel_vmap_range(io->vma_invalidate_address, | |
122 | io->vma_invalidate_size); | |
bb91bc7b | 123 | |
6f1c819c | 124 | mempool_free(io, &io->client->pool); |
97e7cdf1 JT |
125 | fn(error_bits, context); |
126 | } | |
1da177e4 | 127 | |
4e4cbee9 | 128 | static void dec_count(struct io *io, unsigned int region, blk_status_t error) |
97e7cdf1 JT |
129 | { |
130 | if (error) | |
131 | set_bit(region, &io->error_bits); | |
1da177e4 | 132 | |
97e7cdf1 JT |
133 | if (atomic_dec_and_test(&io->count)) |
134 | complete_io(io); | |
1da177e4 LT |
135 | } |
136 | ||
4246a0b6 | 137 | static void endio(struct bio *bio) |
1da177e4 | 138 | { |
c897feb3 HM |
139 | struct io *io; |
140 | unsigned region; | |
4e4cbee9 | 141 | blk_status_t error; |
1da177e4 | 142 | |
4e4cbee9 | 143 | if (bio->bi_status && bio_data_dir(bio) == READ) |
1da177e4 LT |
144 | zero_fill_bio(bio); |
145 | ||
c897feb3 HM |
146 | /* |
147 | * The bio destructor in bio_put() may use the io object. | |
148 | */ | |
f1e53987 | 149 | retrieve_io_and_region_from_bio(bio, &io, ®ion); |
c897feb3 | 150 | |
4e4cbee9 | 151 | error = bio->bi_status; |
1da177e4 LT |
152 | bio_put(bio); |
153 | ||
9b81c842 | 154 | dec_count(io, region, error); |
1da177e4 LT |
155 | } |
156 | ||
157 | /*----------------------------------------------------------------- | |
158 | * These little objects provide an abstraction for getting a new | |
159 | * destination page for io. | |
160 | *---------------------------------------------------------------*/ | |
161 | struct dpages { | |
162 | void (*get_page)(struct dpages *dp, | |
163 | struct page **p, unsigned long *len, unsigned *offset); | |
164 | void (*next_page)(struct dpages *dp); | |
165 | ||
cacc7b05 ML |
166 | union { |
167 | unsigned context_u; | |
168 | struct bvec_iter context_bi; | |
169 | }; | |
1da177e4 | 170 | void *context_ptr; |
bb91bc7b MP |
171 | |
172 | void *vma_invalidate_address; | |
173 | unsigned long vma_invalidate_size; | |
1da177e4 LT |
174 | }; |
175 | ||
176 | /* | |
177 | * Functions for getting the pages from a list. | |
178 | */ | |
179 | static void list_get_page(struct dpages *dp, | |
180 | struct page **p, unsigned long *len, unsigned *offset) | |
181 | { | |
182 | unsigned o = dp->context_u; | |
183 | struct page_list *pl = (struct page_list *) dp->context_ptr; | |
184 | ||
185 | *p = pl->page; | |
186 | *len = PAGE_SIZE - o; | |
187 | *offset = o; | |
188 | } | |
189 | ||
190 | static void list_next_page(struct dpages *dp) | |
191 | { | |
192 | struct page_list *pl = (struct page_list *) dp->context_ptr; | |
193 | dp->context_ptr = pl->next; | |
194 | dp->context_u = 0; | |
195 | } | |
196 | ||
197 | static void list_dp_init(struct dpages *dp, struct page_list *pl, unsigned offset) | |
198 | { | |
199 | dp->get_page = list_get_page; | |
200 | dp->next_page = list_next_page; | |
201 | dp->context_u = offset; | |
202 | dp->context_ptr = pl; | |
203 | } | |
204 | ||
205 | /* | |
206 | * Functions for getting the pages from a bvec. | |
207 | */ | |
d73f9907 MP |
208 | static void bio_get_page(struct dpages *dp, struct page **p, |
209 | unsigned long *len, unsigned *offset) | |
1da177e4 | 210 | { |
cacc7b05 ML |
211 | struct bio_vec bvec = bvec_iter_bvec((struct bio_vec *)dp->context_ptr, |
212 | dp->context_bi); | |
213 | ||
214 | *p = bvec.bv_page; | |
215 | *len = bvec.bv_len; | |
216 | *offset = bvec.bv_offset; | |
217 | ||
218 | /* avoid figuring it out again in bio_next_page() */ | |
219 | dp->context_bi.bi_sector = (sector_t)bvec.bv_len; | |
1da177e4 LT |
220 | } |
221 | ||
003b5c57 | 222 | static void bio_next_page(struct dpages *dp) |
1da177e4 | 223 | { |
cacc7b05 ML |
224 | unsigned int len = (unsigned int)dp->context_bi.bi_sector; |
225 | ||
226 | bvec_iter_advance((struct bio_vec *)dp->context_ptr, | |
227 | &dp->context_bi, len); | |
1da177e4 LT |
228 | } |
229 | ||
003b5c57 | 230 | static void bio_dp_init(struct dpages *dp, struct bio *bio) |
1da177e4 | 231 | { |
003b5c57 KO |
232 | dp->get_page = bio_get_page; |
233 | dp->next_page = bio_next_page; | |
cacc7b05 ML |
234 | |
235 | /* | |
236 | * We just use bvec iterator to retrieve pages, so it is ok to | |
237 | * access the bvec table directly here | |
238 | */ | |
239 | dp->context_ptr = bio->bi_io_vec; | |
240 | dp->context_bi = bio->bi_iter; | |
1da177e4 LT |
241 | } |
242 | ||
c8b03afe HM |
243 | /* |
244 | * Functions for getting the pages from a VMA. | |
245 | */ | |
1da177e4 LT |
246 | static void vm_get_page(struct dpages *dp, |
247 | struct page **p, unsigned long *len, unsigned *offset) | |
248 | { | |
249 | *p = vmalloc_to_page(dp->context_ptr); | |
250 | *offset = dp->context_u; | |
251 | *len = PAGE_SIZE - dp->context_u; | |
252 | } | |
253 | ||
254 | static void vm_next_page(struct dpages *dp) | |
255 | { | |
256 | dp->context_ptr += PAGE_SIZE - dp->context_u; | |
257 | dp->context_u = 0; | |
258 | } | |
259 | ||
260 | static void vm_dp_init(struct dpages *dp, void *data) | |
261 | { | |
262 | dp->get_page = vm_get_page; | |
263 | dp->next_page = vm_next_page; | |
93bbf583 | 264 | dp->context_u = offset_in_page(data); |
1da177e4 LT |
265 | dp->context_ptr = data; |
266 | } | |
267 | ||
c8b03afe HM |
268 | /* |
269 | * Functions for getting the pages from kernel memory. | |
270 | */ | |
271 | static void km_get_page(struct dpages *dp, struct page **p, unsigned long *len, | |
272 | unsigned *offset) | |
273 | { | |
274 | *p = virt_to_page(dp->context_ptr); | |
275 | *offset = dp->context_u; | |
276 | *len = PAGE_SIZE - dp->context_u; | |
277 | } | |
278 | ||
279 | static void km_next_page(struct dpages *dp) | |
280 | { | |
281 | dp->context_ptr += PAGE_SIZE - dp->context_u; | |
282 | dp->context_u = 0; | |
283 | } | |
284 | ||
285 | static void km_dp_init(struct dpages *dp, void *data) | |
286 | { | |
287 | dp->get_page = km_get_page; | |
288 | dp->next_page = km_next_page; | |
93bbf583 | 289 | dp->context_u = offset_in_page(data); |
c8b03afe HM |
290 | dp->context_ptr = data; |
291 | } | |
292 | ||
1da177e4 LT |
293 | /*----------------------------------------------------------------- |
294 | * IO routines that accept a list of pages. | |
295 | *---------------------------------------------------------------*/ | |
e6047149 MC |
296 | static void do_region(int op, int op_flags, unsigned region, |
297 | struct dm_io_region *where, struct dpages *dp, | |
298 | struct io *io) | |
1da177e4 LT |
299 | { |
300 | struct bio *bio; | |
301 | struct page *page; | |
302 | unsigned long len; | |
303 | unsigned offset; | |
304 | unsigned num_bvecs; | |
305 | sector_t remaining = where->count; | |
0c535e0d | 306 | struct request_queue *q = bdev_get_queue(where->bdev); |
70d6c400 MS |
307 | unsigned short logical_block_size = queue_logical_block_size(q); |
308 | sector_t num_sectors; | |
3f649ab7 | 309 | unsigned int special_cmd_max_sectors; |
1da177e4 | 310 | |
e5db2980 DW |
311 | /* |
312 | * Reject unsupported discard and write same requests. | |
313 | */ | |
e6047149 | 314 | if (op == REQ_OP_DISCARD) |
e5db2980 | 315 | special_cmd_max_sectors = q->limits.max_discard_sectors; |
ac62d620 CH |
316 | else if (op == REQ_OP_WRITE_ZEROES) |
317 | special_cmd_max_sectors = q->limits.max_write_zeroes_sectors; | |
e6047149 | 318 | else if (op == REQ_OP_WRITE_SAME) |
e5db2980 | 319 | special_cmd_max_sectors = q->limits.max_write_same_sectors; |
ac62d620 | 320 | if ((op == REQ_OP_DISCARD || op == REQ_OP_WRITE_ZEROES || |
feb7695f MS |
321 | op == REQ_OP_WRITE_SAME) && special_cmd_max_sectors == 0) { |
322 | atomic_inc(&io->count); | |
4e4cbee9 | 323 | dec_count(io, region, BLK_STS_NOTSUPP); |
37527b86 DW |
324 | return; |
325 | } | |
326 | ||
12fc0f49 | 327 | /* |
e6047149 | 328 | * where->count may be zero if op holds a flush and we need to |
d87f4c14 | 329 | * send a zero-sized flush. |
12fc0f49 MP |
330 | */ |
331 | do { | |
1da177e4 | 332 | /* |
f1e53987 | 333 | * Allocate a suitably sized-bio. |
1da177e4 | 334 | */ |
0f5d690f CH |
335 | switch (op) { |
336 | case REQ_OP_DISCARD: | |
ac62d620 | 337 | case REQ_OP_WRITE_ZEROES: |
0f5d690f CH |
338 | num_bvecs = 0; |
339 | break; | |
340 | case REQ_OP_WRITE_SAME: | |
0c535e0d | 341 | num_bvecs = 1; |
0f5d690f CH |
342 | break; |
343 | default: | |
5f7136db MWO |
344 | num_bvecs = bio_max_segs(dm_sector_div_up(remaining, |
345 | (PAGE_SIZE >> SECTOR_SHIFT))); | |
0f5d690f | 346 | } |
0c535e0d | 347 | |
6f1c819c | 348 | bio = bio_alloc_bioset(GFP_NOIO, num_bvecs, &io->client->bios); |
4f024f37 | 349 | bio->bi_iter.bi_sector = where->sector + (where->count - remaining); |
74d46992 | 350 | bio_set_dev(bio, where->bdev); |
1da177e4 | 351 | bio->bi_end_io = endio; |
e6047149 | 352 | bio_set_op_attrs(bio, op, op_flags); |
f1e53987 | 353 | store_io_and_region_in_bio(bio, io, region); |
1da177e4 | 354 | |
ac62d620 | 355 | if (op == REQ_OP_DISCARD || op == REQ_OP_WRITE_ZEROES) { |
e5db2980 | 356 | num_sectors = min_t(sector_t, special_cmd_max_sectors, remaining); |
4f024f37 | 357 | bio->bi_iter.bi_size = num_sectors << SECTOR_SHIFT; |
70d6c400 | 358 | remaining -= num_sectors; |
e6047149 | 359 | } else if (op == REQ_OP_WRITE_SAME) { |
70d6c400 MS |
360 | /* |
361 | * WRITE SAME only uses a single page. | |
362 | */ | |
363 | dp->get_page(dp, &page, &len, &offset); | |
364 | bio_add_page(bio, page, logical_block_size, offset); | |
e5db2980 | 365 | num_sectors = min_t(sector_t, special_cmd_max_sectors, remaining); |
4f024f37 | 366 | bio->bi_iter.bi_size = num_sectors << SECTOR_SHIFT; |
70d6c400 MS |
367 | |
368 | offset = 0; | |
369 | remaining -= num_sectors; | |
370 | dp->next_page(dp); | |
0c535e0d MB |
371 | } else while (remaining) { |
372 | /* | |
373 | * Try and add as many pages as possible. | |
374 | */ | |
1da177e4 LT |
375 | dp->get_page(dp, &page, &len, &offset); |
376 | len = min(len, to_bytes(remaining)); | |
377 | if (!bio_add_page(bio, page, len, offset)) | |
378 | break; | |
379 | ||
380 | offset = 0; | |
381 | remaining -= to_sector(len); | |
382 | dp->next_page(dp); | |
383 | } | |
384 | ||
385 | atomic_inc(&io->count); | |
4e49ea4a | 386 | submit_bio(bio); |
12fc0f49 | 387 | } while (remaining); |
1da177e4 LT |
388 | } |
389 | ||
e6047149 | 390 | static void dispatch_io(int op, int op_flags, unsigned int num_regions, |
22a1ceb1 | 391 | struct dm_io_region *where, struct dpages *dp, |
1da177e4 LT |
392 | struct io *io, int sync) |
393 | { | |
394 | int i; | |
395 | struct dpages old_pages = *dp; | |
396 | ||
f1e53987 MP |
397 | BUG_ON(num_regions > DM_IO_MAX_REGIONS); |
398 | ||
1da177e4 | 399 | if (sync) |
e6047149 | 400 | op_flags |= REQ_SYNC; |
1da177e4 LT |
401 | |
402 | /* | |
403 | * For multiple regions we need to be careful to rewind | |
404 | * the dp object for each call to do_region. | |
405 | */ | |
406 | for (i = 0; i < num_regions; i++) { | |
407 | *dp = old_pages; | |
28a8f0d3 | 408 | if (where[i].count || (op_flags & REQ_PREFLUSH)) |
e6047149 | 409 | do_region(op, op_flags, i, where + i, dp, io); |
1da177e4 LT |
410 | } |
411 | ||
412 | /* | |
f00b16ad | 413 | * Drop the extra reference that we were holding to avoid |
1da177e4 LT |
414 | * the io being completed too early. |
415 | */ | |
416 | dec_count(io, 0, 0); | |
417 | } | |
418 | ||
97e7cdf1 JT |
419 | struct sync_io { |
420 | unsigned long error_bits; | |
421 | struct completion wait; | |
422 | }; | |
423 | ||
424 | static void sync_io_complete(unsigned long error, void *context) | |
425 | { | |
426 | struct sync_io *sio = context; | |
427 | ||
428 | sio->error_bits = error; | |
429 | complete(&sio->wait); | |
430 | } | |
431 | ||
891ce207 | 432 | static int sync_io(struct dm_io_client *client, unsigned int num_regions, |
e6047149 MC |
433 | struct dm_io_region *where, int op, int op_flags, |
434 | struct dpages *dp, unsigned long *error_bits) | |
1da177e4 | 435 | { |
97e7cdf1 JT |
436 | struct io *io; |
437 | struct sync_io sio; | |
1da177e4 | 438 | |
e6047149 | 439 | if (num_regions > 1 && !op_is_write(op)) { |
1da177e4 LT |
440 | WARN_ON(1); |
441 | return -EIO; | |
442 | } | |
443 | ||
97e7cdf1 JT |
444 | init_completion(&sio.wait); |
445 | ||
6f1c819c | 446 | io = mempool_alloc(&client->pool, GFP_NOIO); |
f1e53987 | 447 | io->error_bits = 0; |
f1e53987 | 448 | atomic_set(&io->count, 1); /* see dispatch_io() */ |
f1e53987 | 449 | io->client = client; |
97e7cdf1 JT |
450 | io->callback = sync_io_complete; |
451 | io->context = &sio; | |
1da177e4 | 452 | |
bb91bc7b MP |
453 | io->vma_invalidate_address = dp->vma_invalidate_address; |
454 | io->vma_invalidate_size = dp->vma_invalidate_size; | |
455 | ||
e6047149 | 456 | dispatch_io(op, op_flags, num_regions, where, dp, io, 1); |
1da177e4 | 457 | |
97e7cdf1 | 458 | wait_for_completion_io(&sio.wait); |
1da177e4 | 459 | |
891ce207 | 460 | if (error_bits) |
97e7cdf1 | 461 | *error_bits = sio.error_bits; |
891ce207 | 462 | |
97e7cdf1 | 463 | return sio.error_bits ? -EIO : 0; |
1da177e4 LT |
464 | } |
465 | ||
891ce207 | 466 | static int async_io(struct dm_io_client *client, unsigned int num_regions, |
e6047149 MC |
467 | struct dm_io_region *where, int op, int op_flags, |
468 | struct dpages *dp, io_notify_fn fn, void *context) | |
1da177e4 LT |
469 | { |
470 | struct io *io; | |
471 | ||
e6047149 | 472 | if (num_regions > 1 && !op_is_write(op)) { |
1da177e4 LT |
473 | WARN_ON(1); |
474 | fn(1, context); | |
475 | return -EIO; | |
476 | } | |
477 | ||
6f1c819c | 478 | io = mempool_alloc(&client->pool, GFP_NOIO); |
e01fd7ee | 479 | io->error_bits = 0; |
1da177e4 | 480 | atomic_set(&io->count, 1); /* see dispatch_io() */ |
891ce207 | 481 | io->client = client; |
1da177e4 LT |
482 | io->callback = fn; |
483 | io->context = context; | |
484 | ||
bb91bc7b MP |
485 | io->vma_invalidate_address = dp->vma_invalidate_address; |
486 | io->vma_invalidate_size = dp->vma_invalidate_size; | |
487 | ||
e6047149 | 488 | dispatch_io(op, op_flags, num_regions, where, dp, io, 0); |
1da177e4 LT |
489 | return 0; |
490 | } | |
491 | ||
bb91bc7b MP |
492 | static int dp_init(struct dm_io_request *io_req, struct dpages *dp, |
493 | unsigned long size) | |
c8b03afe HM |
494 | { |
495 | /* Set up dpages based on memory type */ | |
bb91bc7b MP |
496 | |
497 | dp->vma_invalidate_address = NULL; | |
498 | dp->vma_invalidate_size = 0; | |
499 | ||
c8b03afe HM |
500 | switch (io_req->mem.type) { |
501 | case DM_IO_PAGE_LIST: | |
502 | list_dp_init(dp, io_req->mem.ptr.pl, io_req->mem.offset); | |
503 | break; | |
504 | ||
003b5c57 KO |
505 | case DM_IO_BIO: |
506 | bio_dp_init(dp, io_req->mem.ptr.bio); | |
c8b03afe HM |
507 | break; |
508 | ||
509 | case DM_IO_VMA: | |
bb91bc7b | 510 | flush_kernel_vmap_range(io_req->mem.ptr.vma, size); |
e6047149 | 511 | if (io_req->bi_op == REQ_OP_READ) { |
bb91bc7b MP |
512 | dp->vma_invalidate_address = io_req->mem.ptr.vma; |
513 | dp->vma_invalidate_size = size; | |
514 | } | |
c8b03afe HM |
515 | vm_dp_init(dp, io_req->mem.ptr.vma); |
516 | break; | |
517 | ||
518 | case DM_IO_KMEM: | |
519 | km_dp_init(dp, io_req->mem.ptr.addr); | |
520 | break; | |
521 | ||
522 | default: | |
523 | return -EINVAL; | |
524 | } | |
525 | ||
526 | return 0; | |
527 | } | |
528 | ||
529 | /* | |
7ff14a36 MP |
530 | * New collapsed (a)synchronous interface. |
531 | * | |
532 | * If the IO is asynchronous (i.e. it has notify.fn), you must either unplug | |
1eff9d32 JA |
533 | * the queue with blk_unplug() some time later or set REQ_SYNC in |
534 | * io_req->bi_opf. If you fail to do one of these, the IO will be submitted to | |
535 | * the disk after q->unplug_delay, which defaults to 3ms in blk-settings.c. | |
c8b03afe HM |
536 | */ |
537 | int dm_io(struct dm_io_request *io_req, unsigned num_regions, | |
22a1ceb1 | 538 | struct dm_io_region *where, unsigned long *sync_error_bits) |
c8b03afe HM |
539 | { |
540 | int r; | |
541 | struct dpages dp; | |
542 | ||
bb91bc7b | 543 | r = dp_init(io_req, &dp, (unsigned long)where->count << SECTOR_SHIFT); |
c8b03afe HM |
544 | if (r) |
545 | return r; | |
546 | ||
547 | if (!io_req->notify.fn) | |
548 | return sync_io(io_req->client, num_regions, where, | |
e6047149 MC |
549 | io_req->bi_op, io_req->bi_op_flags, &dp, |
550 | sync_error_bits); | |
c8b03afe | 551 | |
e6047149 MC |
552 | return async_io(io_req->client, num_regions, where, io_req->bi_op, |
553 | io_req->bi_op_flags, &dp, io_req->notify.fn, | |
554 | io_req->notify.context); | |
c8b03afe HM |
555 | } |
556 | EXPORT_SYMBOL(dm_io); | |
952b3557 MP |
557 | |
558 | int __init dm_io_init(void) | |
559 | { | |
560 | _dm_io_cache = KMEM_CACHE(io, 0); | |
561 | if (!_dm_io_cache) | |
562 | return -ENOMEM; | |
563 | ||
564 | return 0; | |
565 | } | |
566 | ||
567 | void dm_io_exit(void) | |
568 | { | |
569 | kmem_cache_destroy(_dm_io_cache); | |
570 | _dm_io_cache = NULL; | |
571 | } |