Commit | Line | Data |
---|---|---|
274dcf55 MM |
1 | /* |
2 | * (C) 2001 Clemson University and The University of Chicago | |
3 | * | |
4 | * See COPYING in top-level directory. | |
5 | */ | |
6 | #include "protocol.h" | |
575e9461 MM |
7 | #include "orangefs-kernel.h" |
8 | #include "orangefs-bufmap.h" | |
274dcf55 | 9 | |
ea2c9c9f AV |
10 | struct slot_map { |
11 | int c; | |
12 | wait_queue_head_t q; | |
13 | int count; | |
14 | unsigned long *map; | |
15 | }; | |
16 | ||
17 | static struct slot_map rw_map = { | |
18 | .c = -1, | |
19 | .q = __WAIT_QUEUE_HEAD_INITIALIZER(rw_map.q) | |
20 | }; | |
21 | static struct slot_map readdir_map = { | |
22 | .c = -1, | |
23 | .q = __WAIT_QUEUE_HEAD_INITIALIZER(readdir_map.q) | |
24 | }; | |
25 | ||
26 | ||
27 | static void install(struct slot_map *m, int count, unsigned long *map) | |
28 | { | |
29 | spin_lock(&m->q.lock); | |
30 | m->c = m->count = count; | |
31 | m->map = map; | |
32 | wake_up_all_locked(&m->q); | |
33 | spin_unlock(&m->q.lock); | |
34 | } | |
35 | ||
36 | static void mark_killed(struct slot_map *m) | |
37 | { | |
38 | spin_lock(&m->q.lock); | |
39 | m->c -= m->count + 1; | |
40 | spin_unlock(&m->q.lock); | |
41 | } | |
42 | ||
43 | static void run_down(struct slot_map *m) | |
44 | { | |
45 | DEFINE_WAIT(wait); | |
46 | spin_lock(&m->q.lock); | |
47 | if (m->c != -1) { | |
48 | for (;;) { | |
49 | if (likely(list_empty(&wait.task_list))) | |
50 | __add_wait_queue_tail(&m->q, &wait); | |
51 | set_current_state(TASK_UNINTERRUPTIBLE); | |
52 | ||
53 | if (m->c == -1) | |
54 | break; | |
55 | ||
56 | spin_unlock(&m->q.lock); | |
57 | schedule(); | |
58 | spin_lock(&m->q.lock); | |
59 | } | |
60 | __remove_wait_queue(&m->q, &wait); | |
61 | __set_current_state(TASK_RUNNING); | |
62 | } | |
63 | m->map = NULL; | |
64 | spin_unlock(&m->q.lock); | |
65 | } | |
66 | ||
67 | static void put(struct slot_map *m, int slot) | |
68 | { | |
69 | int v; | |
70 | spin_lock(&m->q.lock); | |
71 | __clear_bit(slot, m->map); | |
72 | v = ++m->c; | |
73 | if (unlikely(v == 1)) /* no free slots -> one free slot */ | |
74 | wake_up_locked(&m->q); | |
75 | else if (unlikely(v == -1)) /* finished dying */ | |
76 | wake_up_all_locked(&m->q); | |
77 | spin_unlock(&m->q.lock); | |
78 | } | |
79 | ||
80 | static int wait_for_free(struct slot_map *m) | |
81 | { | |
82 | long left = slot_timeout_secs * HZ; | |
83 | DEFINE_WAIT(wait); | |
84 | ||
85 | do { | |
86 | long n = left, t; | |
87 | if (likely(list_empty(&wait.task_list))) | |
88 | __add_wait_queue_tail_exclusive(&m->q, &wait); | |
89 | set_current_state(TASK_INTERRUPTIBLE); | |
90 | ||
91 | if (m->c > 0) | |
92 | break; | |
93 | ||
94 | if (m->c < 0) { | |
95 | /* we are waiting for map to be installed */ | |
96 | /* it would better be there soon, or we go away */ | |
97 | if (n > ORANGEFS_BUFMAP_WAIT_TIMEOUT_SECS * HZ) | |
98 | n = ORANGEFS_BUFMAP_WAIT_TIMEOUT_SECS * HZ; | |
99 | } | |
100 | spin_unlock(&m->q.lock); | |
101 | t = schedule_timeout(n); | |
102 | spin_lock(&m->q.lock); | |
103 | if (unlikely(!t) && n != left && m->c < 0) | |
104 | left = t; | |
105 | else | |
106 | left = t + (left - n); | |
107 | if (unlikely(signal_pending(current))) | |
108 | left = -EINTR; | |
109 | } while (left > 0); | |
110 | ||
111 | if (!list_empty(&wait.task_list)) | |
112 | list_del(&wait.task_list); | |
113 | else if (left <= 0 && waitqueue_active(&m->q)) | |
114 | __wake_up_locked_key(&m->q, TASK_INTERRUPTIBLE, NULL); | |
115 | __set_current_state(TASK_RUNNING); | |
116 | ||
117 | if (likely(left > 0)) | |
118 | return 0; | |
119 | ||
120 | return left < 0 ? -EINTR : -ETIMEDOUT; | |
121 | } | |
122 | ||
123 | static int get(struct slot_map *m) | |
124 | { | |
125 | int res = 0; | |
126 | spin_lock(&m->q.lock); | |
127 | if (unlikely(m->c <= 0)) | |
128 | res = wait_for_free(m); | |
129 | if (likely(!res)) { | |
130 | m->c--; | |
131 | res = find_first_zero_bit(m->map, m->count); | |
132 | __set_bit(res, m->map); | |
133 | } | |
134 | spin_unlock(&m->q.lock); | |
135 | return res; | |
136 | } | |
274dcf55 | 137 | |
bf89f584 MB |
138 | /* used to describe mapped buffers */ |
139 | struct orangefs_bufmap_desc { | |
140 | void *uaddr; /* user space address pointer */ | |
141 | struct page **page_array; /* array of mapped pages */ | |
142 | int array_count; /* size of above arrays */ | |
143 | struct list_head list_link; | |
144 | }; | |
145 | ||
8bb8aefd | 146 | static struct orangefs_bufmap { |
274dcf55 MM |
147 | int desc_size; |
148 | int desc_shift; | |
149 | int desc_count; | |
150 | int total_size; | |
151 | int page_count; | |
152 | ||
153 | struct page **page_array; | |
8bb8aefd | 154 | struct orangefs_bufmap_desc *desc_array; |
274dcf55 MM |
155 | |
156 | /* array to track usage of buffer descriptors */ | |
ea2c9c9f | 157 | unsigned long *buffer_index_array; |
274dcf55 MM |
158 | |
159 | /* array to track usage of buffer descriptors for readdir */ | |
ea2c9c9f AV |
160 | #define N DIV_ROUND_UP(ORANGEFS_READDIR_DEFAULT_DESC_COUNT, BITS_PER_LONG) |
161 | unsigned long readdir_index_array[N]; | |
162 | #undef N | |
8bb8aefd | 163 | } *__orangefs_bufmap; |
274dcf55 | 164 | |
8bb8aefd | 165 | static DEFINE_SPINLOCK(orangefs_bufmap_lock); |
274dcf55 MM |
166 | |
167 | static void | |
8bb8aefd | 168 | orangefs_bufmap_unmap(struct orangefs_bufmap *bufmap) |
274dcf55 MM |
169 | { |
170 | int i; | |
171 | ||
172 | for (i = 0; i < bufmap->page_count; i++) | |
09cbfeaf | 173 | put_page(bufmap->page_array[i]); |
274dcf55 MM |
174 | } |
175 | ||
176 | static void | |
8bb8aefd | 177 | orangefs_bufmap_free(struct orangefs_bufmap *bufmap) |
274dcf55 MM |
178 | { |
179 | kfree(bufmap->page_array); | |
180 | kfree(bufmap->desc_array); | |
181 | kfree(bufmap->buffer_index_array); | |
182 | kfree(bufmap); | |
183 | } | |
184 | ||
b09d10df MB |
185 | /* |
186 | * XXX: Can the size and shift change while the caller gives up the | |
187 | * XXX: lock between calling this and doing something useful? | |
188 | */ | |
189 | ||
765a75b3 | 190 | int orangefs_bufmap_size_query(void) |
274dcf55 | 191 | { |
b09d10df MB |
192 | struct orangefs_bufmap *bufmap; |
193 | int size = 0; | |
17804184 AV |
194 | spin_lock(&orangefs_bufmap_lock); |
195 | bufmap = __orangefs_bufmap; | |
196 | if (bufmap) | |
b09d10df | 197 | size = bufmap->desc_size; |
17804184 | 198 | spin_unlock(&orangefs_bufmap_lock); |
274dcf55 MM |
199 | return size; |
200 | } | |
201 | ||
765a75b3 | 202 | int orangefs_bufmap_shift_query(void) |
274dcf55 | 203 | { |
b09d10df MB |
204 | struct orangefs_bufmap *bufmap; |
205 | int shift = 0; | |
17804184 AV |
206 | spin_lock(&orangefs_bufmap_lock); |
207 | bufmap = __orangefs_bufmap; | |
208 | if (bufmap) | |
b09d10df | 209 | shift = bufmap->desc_shift; |
17804184 | 210 | spin_unlock(&orangefs_bufmap_lock); |
274dcf55 MM |
211 | return shift; |
212 | } | |
213 | ||
214 | static DECLARE_WAIT_QUEUE_HEAD(bufmap_waitq); | |
215 | static DECLARE_WAIT_QUEUE_HEAD(readdir_waitq); | |
216 | ||
217 | /* | |
7d221485 | 218 | * orangefs_get_bufmap_init |
274dcf55 MM |
219 | * |
220 | * If bufmap_init is 1, then the shared memory system, including the | |
221 | * buffer_index_array, is available. Otherwise, it is not. | |
222 | * | |
223 | * returns the value of bufmap_init | |
224 | */ | |
7d221485 | 225 | int orangefs_get_bufmap_init(void) |
274dcf55 | 226 | { |
8bb8aefd | 227 | return __orangefs_bufmap ? 1 : 0; |
274dcf55 MM |
228 | } |
229 | ||
230 | ||
8bb8aefd YL |
231 | static struct orangefs_bufmap * |
232 | orangefs_bufmap_alloc(struct ORANGEFS_dev_map_desc *user_desc) | |
274dcf55 | 233 | { |
8bb8aefd | 234 | struct orangefs_bufmap *bufmap; |
274dcf55 MM |
235 | |
236 | bufmap = kzalloc(sizeof(*bufmap), GFP_KERNEL); | |
237 | if (!bufmap) | |
238 | goto out; | |
239 | ||
274dcf55 MM |
240 | bufmap->total_size = user_desc->total_size; |
241 | bufmap->desc_count = user_desc->count; | |
242 | bufmap->desc_size = user_desc->size; | |
243 | bufmap->desc_shift = ilog2(bufmap->desc_size); | |
244 | ||
274dcf55 | 245 | bufmap->buffer_index_array = |
ea2c9c9f | 246 | kzalloc(DIV_ROUND_UP(bufmap->desc_count, BITS_PER_LONG), GFP_KERNEL); |
274dcf55 | 247 | if (!bufmap->buffer_index_array) { |
8bb8aefd | 248 | gossip_err("orangefs: could not allocate %d buffer indices\n", |
274dcf55 MM |
249 | bufmap->desc_count); |
250 | goto out_free_bufmap; | |
251 | } | |
274dcf55 MM |
252 | |
253 | bufmap->desc_array = | |
8bb8aefd | 254 | kcalloc(bufmap->desc_count, sizeof(struct orangefs_bufmap_desc), |
274dcf55 MM |
255 | GFP_KERNEL); |
256 | if (!bufmap->desc_array) { | |
8bb8aefd | 257 | gossip_err("orangefs: could not allocate %d descriptors\n", |
274dcf55 MM |
258 | bufmap->desc_count); |
259 | goto out_free_index_array; | |
260 | } | |
261 | ||
262 | bufmap->page_count = bufmap->total_size / PAGE_SIZE; | |
263 | ||
264 | /* allocate storage to track our page mappings */ | |
265 | bufmap->page_array = | |
266 | kcalloc(bufmap->page_count, sizeof(struct page *), GFP_KERNEL); | |
267 | if (!bufmap->page_array) | |
268 | goto out_free_desc_array; | |
269 | ||
270 | return bufmap; | |
271 | ||
272 | out_free_desc_array: | |
273 | kfree(bufmap->desc_array); | |
274 | out_free_index_array: | |
275 | kfree(bufmap->buffer_index_array); | |
276 | out_free_bufmap: | |
277 | kfree(bufmap); | |
278 | out: | |
279 | return NULL; | |
280 | } | |
281 | ||
282 | static int | |
8bb8aefd YL |
283 | orangefs_bufmap_map(struct orangefs_bufmap *bufmap, |
284 | struct ORANGEFS_dev_map_desc *user_desc) | |
274dcf55 MM |
285 | { |
286 | int pages_per_desc = bufmap->desc_size / PAGE_SIZE; | |
287 | int offset = 0, ret, i; | |
288 | ||
289 | /* map the pages */ | |
16742f2d AV |
290 | ret = get_user_pages_fast((unsigned long)user_desc->ptr, |
291 | bufmap->page_count, 1, bufmap->page_array); | |
274dcf55 MM |
292 | |
293 | if (ret < 0) | |
294 | return ret; | |
295 | ||
296 | if (ret != bufmap->page_count) { | |
8bb8aefd | 297 | gossip_err("orangefs error: asked for %d pages, only got %d.\n", |
274dcf55 MM |
298 | bufmap->page_count, ret); |
299 | ||
300 | for (i = 0; i < ret; i++) { | |
301 | SetPageError(bufmap->page_array[i]); | |
09cbfeaf | 302 | put_page(bufmap->page_array[i]); |
274dcf55 MM |
303 | } |
304 | return -ENOMEM; | |
305 | } | |
306 | ||
307 | /* | |
308 | * ideally we want to get kernel space pointers for each page, but | |
309 | * we can't kmap that many pages at once if highmem is being used. | |
310 | * so instead, we just kmap/kunmap the page address each time the | |
311 | * kaddr is needed. | |
312 | */ | |
313 | for (i = 0; i < bufmap->page_count; i++) | |
314 | flush_dcache_page(bufmap->page_array[i]); | |
315 | ||
316 | /* build a list of available descriptors */ | |
317 | for (offset = 0, i = 0; i < bufmap->desc_count; i++) { | |
318 | bufmap->desc_array[i].page_array = &bufmap->page_array[offset]; | |
319 | bufmap->desc_array[i].array_count = pages_per_desc; | |
320 | bufmap->desc_array[i].uaddr = | |
321 | (user_desc->ptr + (i * pages_per_desc * PAGE_SIZE)); | |
322 | offset += pages_per_desc; | |
323 | } | |
324 | ||
325 | return 0; | |
326 | } | |
327 | ||
328 | /* | |
8bb8aefd | 329 | * orangefs_bufmap_initialize() |
274dcf55 MM |
330 | * |
331 | * initializes the mapped buffer interface | |
332 | * | |
333 | * returns 0 on success, -errno on failure | |
334 | */ | |
8bb8aefd | 335 | int orangefs_bufmap_initialize(struct ORANGEFS_dev_map_desc *user_desc) |
274dcf55 | 336 | { |
8bb8aefd | 337 | struct orangefs_bufmap *bufmap; |
274dcf55 MM |
338 | int ret = -EINVAL; |
339 | ||
340 | gossip_debug(GOSSIP_BUFMAP_DEBUG, | |
8bb8aefd | 341 | "orangefs_bufmap_initialize: called (ptr (" |
274dcf55 MM |
342 | "%p) sz (%d) cnt(%d).\n", |
343 | user_desc->ptr, | |
344 | user_desc->size, | |
345 | user_desc->count); | |
346 | ||
347 | /* | |
348 | * sanity check alignment and size of buffer that caller wants to | |
349 | * work with | |
350 | */ | |
351 | if (PAGE_ALIGN((unsigned long)user_desc->ptr) != | |
352 | (unsigned long)user_desc->ptr) { | |
8bb8aefd | 353 | gossip_err("orangefs error: memory alignment (front). %p\n", |
274dcf55 MM |
354 | user_desc->ptr); |
355 | goto out; | |
356 | } | |
357 | ||
358 | if (PAGE_ALIGN(((unsigned long)user_desc->ptr + user_desc->total_size)) | |
359 | != (unsigned long)(user_desc->ptr + user_desc->total_size)) { | |
8bb8aefd | 360 | gossip_err("orangefs error: memory alignment (back).(%p + %d)\n", |
274dcf55 MM |
361 | user_desc->ptr, |
362 | user_desc->total_size); | |
363 | goto out; | |
364 | } | |
365 | ||
366 | if (user_desc->total_size != (user_desc->size * user_desc->count)) { | |
8bb8aefd | 367 | gossip_err("orangefs error: user provided an oddly sized buffer: (%d, %d, %d)\n", |
274dcf55 MM |
368 | user_desc->total_size, |
369 | user_desc->size, | |
370 | user_desc->count); | |
371 | goto out; | |
372 | } | |
373 | ||
374 | if ((user_desc->size % PAGE_SIZE) != 0) { | |
8bb8aefd | 375 | gossip_err("orangefs error: bufmap size not page size divisible (%d).\n", |
274dcf55 MM |
376 | user_desc->size); |
377 | goto out; | |
378 | } | |
379 | ||
380 | ret = -ENOMEM; | |
8bb8aefd | 381 | bufmap = orangefs_bufmap_alloc(user_desc); |
274dcf55 MM |
382 | if (!bufmap) |
383 | goto out; | |
384 | ||
8bb8aefd | 385 | ret = orangefs_bufmap_map(bufmap, user_desc); |
274dcf55 MM |
386 | if (ret) |
387 | goto out_free_bufmap; | |
388 | ||
389 | ||
8bb8aefd YL |
390 | spin_lock(&orangefs_bufmap_lock); |
391 | if (__orangefs_bufmap) { | |
392 | spin_unlock(&orangefs_bufmap_lock); | |
393 | gossip_err("orangefs: error: bufmap already initialized.\n"); | |
ea2c9c9f | 394 | ret = -EINVAL; |
274dcf55 MM |
395 | goto out_unmap_bufmap; |
396 | } | |
8bb8aefd | 397 | __orangefs_bufmap = bufmap; |
ea2c9c9f AV |
398 | install(&rw_map, |
399 | bufmap->desc_count, | |
400 | bufmap->buffer_index_array); | |
401 | install(&readdir_map, | |
402 | ORANGEFS_READDIR_DEFAULT_DESC_COUNT, | |
403 | bufmap->readdir_index_array); | |
8bb8aefd | 404 | spin_unlock(&orangefs_bufmap_lock); |
274dcf55 | 405 | |
274dcf55 | 406 | gossip_debug(GOSSIP_BUFMAP_DEBUG, |
8bb8aefd | 407 | "orangefs_bufmap_initialize: exiting normally\n"); |
274dcf55 MM |
408 | return 0; |
409 | ||
410 | out_unmap_bufmap: | |
8bb8aefd | 411 | orangefs_bufmap_unmap(bufmap); |
274dcf55 | 412 | out_free_bufmap: |
8bb8aefd | 413 | orangefs_bufmap_free(bufmap); |
274dcf55 MM |
414 | out: |
415 | return ret; | |
416 | } | |
417 | ||
418 | /* | |
8bb8aefd | 419 | * orangefs_bufmap_finalize() |
274dcf55 MM |
420 | * |
421 | * shuts down the mapped buffer interface and releases any resources | |
422 | * associated with it | |
423 | * | |
424 | * no return value | |
425 | */ | |
8bb8aefd | 426 | void orangefs_bufmap_finalize(void) |
274dcf55 | 427 | { |
ea2c9c9f AV |
428 | struct orangefs_bufmap *bufmap = __orangefs_bufmap; |
429 | if (!bufmap) | |
430 | return; | |
8bb8aefd | 431 | gossip_debug(GOSSIP_BUFMAP_DEBUG, "orangefs_bufmap_finalize: called\n"); |
ea2c9c9f AV |
432 | mark_killed(&rw_map); |
433 | mark_killed(&readdir_map); | |
274dcf55 | 434 | gossip_debug(GOSSIP_BUFMAP_DEBUG, |
8bb8aefd | 435 | "orangefs_bufmap_finalize: exiting normally\n"); |
274dcf55 MM |
436 | } |
437 | ||
ea2c9c9f | 438 | void orangefs_bufmap_run_down(void) |
274dcf55 | 439 | { |
ea2c9c9f AV |
440 | struct orangefs_bufmap *bufmap = __orangefs_bufmap; |
441 | if (!bufmap) | |
274dcf55 | 442 | return; |
ea2c9c9f AV |
443 | run_down(&rw_map); |
444 | run_down(&readdir_map); | |
445 | spin_lock(&orangefs_bufmap_lock); | |
446 | __orangefs_bufmap = NULL; | |
447 | spin_unlock(&orangefs_bufmap_lock); | |
448 | orangefs_bufmap_unmap(bufmap); | |
449 | orangefs_bufmap_free(bufmap); | |
274dcf55 MM |
450 | } |
451 | ||
452 | /* | |
8bb8aefd | 453 | * orangefs_bufmap_get() |
274dcf55 MM |
454 | * |
455 | * gets a free mapped buffer descriptor, will sleep until one becomes | |
456 | * available if necessary | |
457 | * | |
b8a99a8f | 458 | * returns slot on success, -errno on failure |
274dcf55 | 459 | */ |
b8a99a8f | 460 | int orangefs_bufmap_get(void) |
274dcf55 | 461 | { |
b8a99a8f | 462 | return get(&rw_map); |
274dcf55 MM |
463 | } |
464 | ||
465 | /* | |
8bb8aefd | 466 | * orangefs_bufmap_put() |
274dcf55 MM |
467 | * |
468 | * returns a mapped buffer descriptor to the collection | |
469 | * | |
470 | * no return value | |
471 | */ | |
1357d06d | 472 | void orangefs_bufmap_put(int buffer_index) |
274dcf55 | 473 | { |
ea2c9c9f | 474 | put(&rw_map, buffer_index); |
274dcf55 MM |
475 | } |
476 | ||
477 | /* | |
7d221485 | 478 | * orangefs_readdir_index_get() |
274dcf55 MM |
479 | * |
480 | * gets a free descriptor, will sleep until one becomes | |
481 | * available if necessary. | |
482 | * Although the readdir buffers are not mapped into kernel space | |
483 | * we could do that at a later point of time. Regardless, these | |
484 | * indices are used by the client-core. | |
485 | * | |
b8a99a8f | 486 | * returns slot on success, -errno on failure |
274dcf55 | 487 | */ |
b8a99a8f | 488 | int orangefs_readdir_index_get(void) |
274dcf55 | 489 | { |
b8a99a8f | 490 | return get(&readdir_map); |
274dcf55 MM |
491 | } |
492 | ||
82d37f19 | 493 | void orangefs_readdir_index_put(int buffer_index) |
274dcf55 | 494 | { |
ea2c9c9f | 495 | put(&readdir_map, buffer_index); |
274dcf55 MM |
496 | } |
497 | ||
b5e376ea MM |
498 | /* |
499 | * we've been handed an iovec, we need to copy it to | |
500 | * the shared memory descriptor at "buffer_index". | |
501 | */ | |
bf6bf606 | 502 | int orangefs_bufmap_copy_from_iovec(struct iov_iter *iter, |
54804949 MM |
503 | int buffer_index, |
504 | size_t size) | |
274dcf55 | 505 | { |
bf6bf606 | 506 | struct orangefs_bufmap_desc *to; |
4d1c4404 | 507 | int i; |
274dcf55 MM |
508 | |
509 | gossip_debug(GOSSIP_BUFMAP_DEBUG, | |
34204fde | 510 | "%s: buffer_index:%d: size:%zu:\n", |
4d1c4404 | 511 | __func__, buffer_index, size); |
274dcf55 | 512 | |
bf6bf606 | 513 | to = &__orangefs_bufmap->desc_array[buffer_index]; |
4d1c4404 | 514 | for (i = 0; size; i++) { |
34204fde AV |
515 | struct page *page = to->page_array[i]; |
516 | size_t n = size; | |
517 | if (n > PAGE_SIZE) | |
518 | n = PAGE_SIZE; | |
519 | n = copy_page_from_iter(page, 0, n, iter); | |
520 | if (!n) | |
521 | return -EFAULT; | |
522 | size -= n; | |
274dcf55 | 523 | } |
34204fde | 524 | return 0; |
274dcf55 | 525 | |
274dcf55 MM |
526 | } |
527 | ||
528 | /* | |
b5e376ea MM |
529 | * we've been handed an iovec, we need to fill it from |
530 | * the shared memory descriptor at "buffer_index". | |
274dcf55 | 531 | */ |
bf6bf606 | 532 | int orangefs_bufmap_copy_to_iovec(struct iov_iter *iter, |
5c278228 AV |
533 | int buffer_index, |
534 | size_t size) | |
274dcf55 | 535 | { |
bf6bf606 | 536 | struct orangefs_bufmap_desc *from; |
4d1c4404 | 537 | int i; |
274dcf55 | 538 | |
bf6bf606 | 539 | from = &__orangefs_bufmap->desc_array[buffer_index]; |
274dcf55 | 540 | gossip_debug(GOSSIP_BUFMAP_DEBUG, |
5c278228 AV |
541 | "%s: buffer_index:%d: size:%zu:\n", |
542 | __func__, buffer_index, size); | |
274dcf55 | 543 | |
274dcf55 | 544 | |
5c278228 AV |
545 | for (i = 0; size; i++) { |
546 | struct page *page = from->page_array[i]; | |
547 | size_t n = size; | |
548 | if (n > PAGE_SIZE) | |
549 | n = PAGE_SIZE; | |
550 | n = copy_page_to_iter(page, 0, n, iter); | |
551 | if (!n) | |
552 | return -EFAULT; | |
553 | size -= n; | |
274dcf55 | 554 | } |
5c278228 | 555 | return 0; |
274dcf55 | 556 | } |