Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
f07c2250 | 2 | * Copyright (c) 2000-2006 Silicon Graphics, Inc. |
7b718769 | 3 | * All Rights Reserved. |
1da177e4 | 4 | * |
7b718769 NS |
5 | * This program is free software; you can redistribute it and/or |
6 | * modify it under the terms of the GNU General Public License as | |
1da177e4 LT |
7 | * published by the Free Software Foundation. |
8 | * | |
7b718769 NS |
9 | * This program is distributed in the hope that it would be useful, |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
1da177e4 | 13 | * |
7b718769 NS |
14 | * You should have received a copy of the GNU General Public License |
15 | * along with this program; if not, write the Free Software Foundation, | |
16 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
1da177e4 | 17 | */ |
93c189c1 | 18 | #include "xfs.h" |
1da177e4 LT |
19 | #include <linux/stddef.h> |
20 | #include <linux/errno.h> | |
21 | #include <linux/slab.h> | |
22 | #include <linux/pagemap.h> | |
23 | #include <linux/init.h> | |
24 | #include <linux/vmalloc.h> | |
25 | #include <linux/bio.h> | |
26 | #include <linux/sysctl.h> | |
27 | #include <linux/proc_fs.h> | |
28 | #include <linux/workqueue.h> | |
29 | #include <linux/percpu.h> | |
30 | #include <linux/blkdev.h> | |
31 | #include <linux/hash.h> | |
4df08c52 | 32 | #include <linux/kthread.h> |
b20a3503 | 33 | #include <linux/migrate.h> |
3fcfab16 | 34 | #include <linux/backing-dev.h> |
1da177e4 | 35 | |
ce8e922c NS |
36 | STATIC kmem_zone_t *xfs_buf_zone; |
37 | STATIC kmem_shaker_t xfs_buf_shake; | |
a6867a68 | 38 | STATIC int xfsbufd(void *); |
27496a8c | 39 | STATIC int xfsbufd_wakeup(int, gfp_t); |
ce8e922c | 40 | STATIC void xfs_buf_delwri_queue(xfs_buf_t *, int); |
23ea4032 CH |
41 | |
42 | STATIC struct workqueue_struct *xfslogd_workqueue; | |
0829c360 | 43 | struct workqueue_struct *xfsdatad_workqueue; |
1da177e4 | 44 | |
ce8e922c | 45 | #ifdef XFS_BUF_TRACE |
1da177e4 | 46 | void |
ce8e922c NS |
47 | xfs_buf_trace( |
48 | xfs_buf_t *bp, | |
1da177e4 LT |
49 | char *id, |
50 | void *data, | |
51 | void *ra) | |
52 | { | |
ce8e922c NS |
53 | ktrace_enter(xfs_buf_trace_buf, |
54 | bp, id, | |
55 | (void *)(unsigned long)bp->b_flags, | |
56 | (void *)(unsigned long)bp->b_hold.counter, | |
57 | (void *)(unsigned long)bp->b_sema.count.counter, | |
1da177e4 LT |
58 | (void *)current, |
59 | data, ra, | |
ce8e922c NS |
60 | (void *)(unsigned long)((bp->b_file_offset>>32) & 0xffffffff), |
61 | (void *)(unsigned long)(bp->b_file_offset & 0xffffffff), | |
62 | (void *)(unsigned long)bp->b_buffer_length, | |
1da177e4 LT |
63 | NULL, NULL, NULL, NULL, NULL); |
64 | } | |
ce8e922c NS |
65 | ktrace_t *xfs_buf_trace_buf; |
66 | #define XFS_BUF_TRACE_SIZE 4096 | |
67 | #define XB_TRACE(bp, id, data) \ | |
68 | xfs_buf_trace(bp, id, (void *)data, (void *)__builtin_return_address(0)) | |
1da177e4 | 69 | #else |
ce8e922c | 70 | #define XB_TRACE(bp, id, data) do { } while (0) |
1da177e4 LT |
71 | #endif |
72 | ||
ce8e922c NS |
73 | #ifdef XFS_BUF_LOCK_TRACKING |
74 | # define XB_SET_OWNER(bp) ((bp)->b_last_holder = current->pid) | |
75 | # define XB_CLEAR_OWNER(bp) ((bp)->b_last_holder = -1) | |
76 | # define XB_GET_OWNER(bp) ((bp)->b_last_holder) | |
1da177e4 | 77 | #else |
ce8e922c NS |
78 | # define XB_SET_OWNER(bp) do { } while (0) |
79 | # define XB_CLEAR_OWNER(bp) do { } while (0) | |
80 | # define XB_GET_OWNER(bp) do { } while (0) | |
1da177e4 LT |
81 | #endif |
82 | ||
ce8e922c NS |
83 | #define xb_to_gfp(flags) \ |
84 | ((((flags) & XBF_READ_AHEAD) ? __GFP_NORETRY : \ | |
85 | ((flags) & XBF_DONT_BLOCK) ? GFP_NOFS : GFP_KERNEL) | __GFP_NOWARN) | |
1da177e4 | 86 | |
ce8e922c NS |
87 | #define xb_to_km(flags) \ |
88 | (((flags) & XBF_DONT_BLOCK) ? KM_NOFS : KM_SLEEP) | |
1da177e4 | 89 | |
ce8e922c NS |
90 | #define xfs_buf_allocate(flags) \ |
91 | kmem_zone_alloc(xfs_buf_zone, xb_to_km(flags)) | |
92 | #define xfs_buf_deallocate(bp) \ | |
93 | kmem_zone_free(xfs_buf_zone, (bp)); | |
1da177e4 LT |
94 | |
95 | /* | |
ce8e922c | 96 | * Page Region interfaces. |
1da177e4 | 97 | * |
ce8e922c NS |
98 | * For pages in filesystems where the blocksize is smaller than the |
99 | * pagesize, we use the page->private field (long) to hold a bitmap | |
100 | * of uptodate regions within the page. | |
1da177e4 | 101 | * |
ce8e922c | 102 | * Each such region is "bytes per page / bits per long" bytes long. |
1da177e4 | 103 | * |
ce8e922c NS |
104 | * NBPPR == number-of-bytes-per-page-region |
105 | * BTOPR == bytes-to-page-region (rounded up) | |
106 | * BTOPRT == bytes-to-page-region-truncated (rounded down) | |
1da177e4 LT |
107 | */ |
108 | #if (BITS_PER_LONG == 32) | |
109 | #define PRSHIFT (PAGE_CACHE_SHIFT - 5) /* (32 == 1<<5) */ | |
110 | #elif (BITS_PER_LONG == 64) | |
111 | #define PRSHIFT (PAGE_CACHE_SHIFT - 6) /* (64 == 1<<6) */ | |
112 | #else | |
113 | #error BITS_PER_LONG must be 32 or 64 | |
114 | #endif | |
115 | #define NBPPR (PAGE_CACHE_SIZE/BITS_PER_LONG) | |
116 | #define BTOPR(b) (((unsigned int)(b) + (NBPPR - 1)) >> PRSHIFT) | |
117 | #define BTOPRT(b) (((unsigned int)(b) >> PRSHIFT)) | |
118 | ||
119 | STATIC unsigned long | |
120 | page_region_mask( | |
121 | size_t offset, | |
122 | size_t length) | |
123 | { | |
124 | unsigned long mask; | |
125 | int first, final; | |
126 | ||
127 | first = BTOPR(offset); | |
128 | final = BTOPRT(offset + length - 1); | |
129 | first = min(first, final); | |
130 | ||
131 | mask = ~0UL; | |
132 | mask <<= BITS_PER_LONG - (final - first); | |
133 | mask >>= BITS_PER_LONG - (final); | |
134 | ||
135 | ASSERT(offset + length <= PAGE_CACHE_SIZE); | |
136 | ASSERT((final - first) < BITS_PER_LONG && (final - first) >= 0); | |
137 | ||
138 | return mask; | |
139 | } | |
140 | ||
141 | STATIC inline void | |
142 | set_page_region( | |
143 | struct page *page, | |
144 | size_t offset, | |
145 | size_t length) | |
146 | { | |
4c21e2f2 HD |
147 | set_page_private(page, |
148 | page_private(page) | page_region_mask(offset, length)); | |
149 | if (page_private(page) == ~0UL) | |
1da177e4 LT |
150 | SetPageUptodate(page); |
151 | } | |
152 | ||
153 | STATIC inline int | |
154 | test_page_region( | |
155 | struct page *page, | |
156 | size_t offset, | |
157 | size_t length) | |
158 | { | |
159 | unsigned long mask = page_region_mask(offset, length); | |
160 | ||
4c21e2f2 | 161 | return (mask && (page_private(page) & mask) == mask); |
1da177e4 LT |
162 | } |
163 | ||
164 | /* | |
ce8e922c | 165 | * Mapping of multi-page buffers into contiguous virtual space |
1da177e4 LT |
166 | */ |
167 | ||
168 | typedef struct a_list { | |
169 | void *vm_addr; | |
170 | struct a_list *next; | |
171 | } a_list_t; | |
172 | ||
173 | STATIC a_list_t *as_free_head; | |
174 | STATIC int as_list_len; | |
175 | STATIC DEFINE_SPINLOCK(as_lock); | |
176 | ||
177 | /* | |
ce8e922c | 178 | * Try to batch vunmaps because they are costly. |
1da177e4 LT |
179 | */ |
180 | STATIC void | |
181 | free_address( | |
182 | void *addr) | |
183 | { | |
184 | a_list_t *aentry; | |
185 | ||
7b04d717 | 186 | aentry = kmalloc(sizeof(a_list_t), GFP_NOWAIT); |
1da177e4 LT |
187 | if (likely(aentry)) { |
188 | spin_lock(&as_lock); | |
189 | aentry->next = as_free_head; | |
190 | aentry->vm_addr = addr; | |
191 | as_free_head = aentry; | |
192 | as_list_len++; | |
193 | spin_unlock(&as_lock); | |
194 | } else { | |
195 | vunmap(addr); | |
196 | } | |
197 | } | |
198 | ||
199 | STATIC void | |
200 | purge_addresses(void) | |
201 | { | |
202 | a_list_t *aentry, *old; | |
203 | ||
204 | if (as_free_head == NULL) | |
205 | return; | |
206 | ||
207 | spin_lock(&as_lock); | |
208 | aentry = as_free_head; | |
209 | as_free_head = NULL; | |
210 | as_list_len = 0; | |
211 | spin_unlock(&as_lock); | |
212 | ||
213 | while ((old = aentry) != NULL) { | |
214 | vunmap(aentry->vm_addr); | |
215 | aentry = aentry->next; | |
216 | kfree(old); | |
217 | } | |
218 | } | |
219 | ||
220 | /* | |
ce8e922c | 221 | * Internal xfs_buf_t object manipulation |
1da177e4 LT |
222 | */ |
223 | ||
224 | STATIC void | |
ce8e922c NS |
225 | _xfs_buf_initialize( |
226 | xfs_buf_t *bp, | |
1da177e4 | 227 | xfs_buftarg_t *target, |
204ab25f | 228 | xfs_off_t range_base, |
1da177e4 | 229 | size_t range_length, |
ce8e922c | 230 | xfs_buf_flags_t flags) |
1da177e4 LT |
231 | { |
232 | /* | |
ce8e922c | 233 | * We don't want certain flags to appear in b_flags. |
1da177e4 | 234 | */ |
ce8e922c NS |
235 | flags &= ~(XBF_LOCK|XBF_MAPPED|XBF_DONT_BLOCK|XBF_READ_AHEAD); |
236 | ||
237 | memset(bp, 0, sizeof(xfs_buf_t)); | |
238 | atomic_set(&bp->b_hold, 1); | |
239 | init_MUTEX_LOCKED(&bp->b_iodonesema); | |
240 | INIT_LIST_HEAD(&bp->b_list); | |
241 | INIT_LIST_HEAD(&bp->b_hash_list); | |
242 | init_MUTEX_LOCKED(&bp->b_sema); /* held, no waiters */ | |
243 | XB_SET_OWNER(bp); | |
244 | bp->b_target = target; | |
245 | bp->b_file_offset = range_base; | |
1da177e4 LT |
246 | /* |
247 | * Set buffer_length and count_desired to the same value initially. | |
248 | * I/O routines should use count_desired, which will be the same in | |
249 | * most cases but may be reset (e.g. XFS recovery). | |
250 | */ | |
ce8e922c NS |
251 | bp->b_buffer_length = bp->b_count_desired = range_length; |
252 | bp->b_flags = flags; | |
253 | bp->b_bn = XFS_BUF_DADDR_NULL; | |
254 | atomic_set(&bp->b_pin_count, 0); | |
255 | init_waitqueue_head(&bp->b_waiters); | |
256 | ||
257 | XFS_STATS_INC(xb_create); | |
258 | XB_TRACE(bp, "initialize", target); | |
1da177e4 LT |
259 | } |
260 | ||
261 | /* | |
ce8e922c NS |
262 | * Allocate a page array capable of holding a specified number |
263 | * of pages, and point the page buf at it. | |
1da177e4 LT |
264 | */ |
265 | STATIC int | |
ce8e922c NS |
266 | _xfs_buf_get_pages( |
267 | xfs_buf_t *bp, | |
1da177e4 | 268 | int page_count, |
ce8e922c | 269 | xfs_buf_flags_t flags) |
1da177e4 LT |
270 | { |
271 | /* Make sure that we have a page list */ | |
ce8e922c NS |
272 | if (bp->b_pages == NULL) { |
273 | bp->b_offset = xfs_buf_poff(bp->b_file_offset); | |
274 | bp->b_page_count = page_count; | |
275 | if (page_count <= XB_PAGES) { | |
276 | bp->b_pages = bp->b_page_array; | |
1da177e4 | 277 | } else { |
ce8e922c NS |
278 | bp->b_pages = kmem_alloc(sizeof(struct page *) * |
279 | page_count, xb_to_km(flags)); | |
280 | if (bp->b_pages == NULL) | |
1da177e4 LT |
281 | return -ENOMEM; |
282 | } | |
ce8e922c | 283 | memset(bp->b_pages, 0, sizeof(struct page *) * page_count); |
1da177e4 LT |
284 | } |
285 | return 0; | |
286 | } | |
287 | ||
288 | /* | |
ce8e922c | 289 | * Frees b_pages if it was allocated. |
1da177e4 LT |
290 | */ |
291 | STATIC void | |
ce8e922c | 292 | _xfs_buf_free_pages( |
1da177e4 LT |
293 | xfs_buf_t *bp) |
294 | { | |
ce8e922c NS |
295 | if (bp->b_pages != bp->b_page_array) { |
296 | kmem_free(bp->b_pages, | |
297 | bp->b_page_count * sizeof(struct page *)); | |
1da177e4 LT |
298 | } |
299 | } | |
300 | ||
301 | /* | |
302 | * Releases the specified buffer. | |
303 | * | |
304 | * The modification state of any associated pages is left unchanged. | |
ce8e922c | 305 | * The buffer most not be on any hash - use xfs_buf_rele instead for |
1da177e4 LT |
306 | * hashed and refcounted buffers |
307 | */ | |
308 | void | |
ce8e922c | 309 | xfs_buf_free( |
1da177e4 LT |
310 | xfs_buf_t *bp) |
311 | { | |
ce8e922c | 312 | XB_TRACE(bp, "free", 0); |
1da177e4 | 313 | |
ce8e922c | 314 | ASSERT(list_empty(&bp->b_hash_list)); |
1da177e4 | 315 | |
ce8e922c | 316 | if (bp->b_flags & _XBF_PAGE_CACHE) { |
1da177e4 LT |
317 | uint i; |
318 | ||
ce8e922c NS |
319 | if ((bp->b_flags & XBF_MAPPED) && (bp->b_page_count > 1)) |
320 | free_address(bp->b_addr - bp->b_offset); | |
1da177e4 | 321 | |
948ecdb4 NS |
322 | for (i = 0; i < bp->b_page_count; i++) { |
323 | struct page *page = bp->b_pages[i]; | |
324 | ||
325 | ASSERT(!PagePrivate(page)); | |
326 | page_cache_release(page); | |
327 | } | |
ce8e922c NS |
328 | _xfs_buf_free_pages(bp); |
329 | } else if (bp->b_flags & _XBF_KMEM_ALLOC) { | |
1da177e4 | 330 | /* |
ce8e922c NS |
331 | * XXX(hch): bp->b_count_desired might be incorrect (see |
332 | * xfs_buf_associate_memory for details), but fortunately | |
1da177e4 LT |
333 | * the Linux version of kmem_free ignores the len argument.. |
334 | */ | |
ce8e922c NS |
335 | kmem_free(bp->b_addr, bp->b_count_desired); |
336 | _xfs_buf_free_pages(bp); | |
1da177e4 LT |
337 | } |
338 | ||
ce8e922c | 339 | xfs_buf_deallocate(bp); |
1da177e4 LT |
340 | } |
341 | ||
342 | /* | |
343 | * Finds all pages for buffer in question and builds it's page list. | |
344 | */ | |
345 | STATIC int | |
ce8e922c | 346 | _xfs_buf_lookup_pages( |
1da177e4 LT |
347 | xfs_buf_t *bp, |
348 | uint flags) | |
349 | { | |
ce8e922c NS |
350 | struct address_space *mapping = bp->b_target->bt_mapping; |
351 | size_t blocksize = bp->b_target->bt_bsize; | |
352 | size_t size = bp->b_count_desired; | |
1da177e4 | 353 | size_t nbytes, offset; |
ce8e922c | 354 | gfp_t gfp_mask = xb_to_gfp(flags); |
1da177e4 LT |
355 | unsigned short page_count, i; |
356 | pgoff_t first; | |
204ab25f | 357 | xfs_off_t end; |
1da177e4 LT |
358 | int error; |
359 | ||
ce8e922c NS |
360 | end = bp->b_file_offset + bp->b_buffer_length; |
361 | page_count = xfs_buf_btoc(end) - xfs_buf_btoct(bp->b_file_offset); | |
1da177e4 | 362 | |
ce8e922c | 363 | error = _xfs_buf_get_pages(bp, page_count, flags); |
1da177e4 LT |
364 | if (unlikely(error)) |
365 | return error; | |
ce8e922c | 366 | bp->b_flags |= _XBF_PAGE_CACHE; |
1da177e4 | 367 | |
ce8e922c NS |
368 | offset = bp->b_offset; |
369 | first = bp->b_file_offset >> PAGE_CACHE_SHIFT; | |
1da177e4 | 370 | |
ce8e922c | 371 | for (i = 0; i < bp->b_page_count; i++) { |
1da177e4 LT |
372 | struct page *page; |
373 | uint retries = 0; | |
374 | ||
375 | retry: | |
376 | page = find_or_create_page(mapping, first + i, gfp_mask); | |
377 | if (unlikely(page == NULL)) { | |
ce8e922c NS |
378 | if (flags & XBF_READ_AHEAD) { |
379 | bp->b_page_count = i; | |
380 | for (i = 0; i < bp->b_page_count; i++) | |
381 | unlock_page(bp->b_pages[i]); | |
1da177e4 LT |
382 | return -ENOMEM; |
383 | } | |
384 | ||
385 | /* | |
386 | * This could deadlock. | |
387 | * | |
388 | * But until all the XFS lowlevel code is revamped to | |
389 | * handle buffer allocation failures we can't do much. | |
390 | */ | |
391 | if (!(++retries % 100)) | |
392 | printk(KERN_ERR | |
393 | "XFS: possible memory allocation " | |
394 | "deadlock in %s (mode:0x%x)\n", | |
395 | __FUNCTION__, gfp_mask); | |
396 | ||
ce8e922c | 397 | XFS_STATS_INC(xb_page_retries); |
23ea4032 | 398 | xfsbufd_wakeup(0, gfp_mask); |
3fcfab16 | 399 | congestion_wait(WRITE, HZ/50); |
1da177e4 LT |
400 | goto retry; |
401 | } | |
402 | ||
ce8e922c | 403 | XFS_STATS_INC(xb_page_found); |
1da177e4 LT |
404 | |
405 | nbytes = min_t(size_t, size, PAGE_CACHE_SIZE - offset); | |
406 | size -= nbytes; | |
407 | ||
948ecdb4 | 408 | ASSERT(!PagePrivate(page)); |
1da177e4 LT |
409 | if (!PageUptodate(page)) { |
410 | page_count--; | |
411 | if (blocksize >= PAGE_CACHE_SIZE) { | |
ce8e922c NS |
412 | if (flags & XBF_READ) |
413 | bp->b_locked = 1; | |
1da177e4 LT |
414 | } else if (!PagePrivate(page)) { |
415 | if (test_page_region(page, offset, nbytes)) | |
416 | page_count++; | |
417 | } | |
418 | } | |
419 | ||
ce8e922c | 420 | bp->b_pages[i] = page; |
1da177e4 LT |
421 | offset = 0; |
422 | } | |
423 | ||
ce8e922c NS |
424 | if (!bp->b_locked) { |
425 | for (i = 0; i < bp->b_page_count; i++) | |
426 | unlock_page(bp->b_pages[i]); | |
1da177e4 LT |
427 | } |
428 | ||
ce8e922c NS |
429 | if (page_count == bp->b_page_count) |
430 | bp->b_flags |= XBF_DONE; | |
1da177e4 | 431 | |
ce8e922c | 432 | XB_TRACE(bp, "lookup_pages", (long)page_count); |
1da177e4 LT |
433 | return error; |
434 | } | |
435 | ||
436 | /* | |
437 | * Map buffer into kernel address-space if nessecary. | |
438 | */ | |
439 | STATIC int | |
ce8e922c | 440 | _xfs_buf_map_pages( |
1da177e4 LT |
441 | xfs_buf_t *bp, |
442 | uint flags) | |
443 | { | |
444 | /* A single page buffer is always mappable */ | |
ce8e922c NS |
445 | if (bp->b_page_count == 1) { |
446 | bp->b_addr = page_address(bp->b_pages[0]) + bp->b_offset; | |
447 | bp->b_flags |= XBF_MAPPED; | |
448 | } else if (flags & XBF_MAPPED) { | |
1da177e4 LT |
449 | if (as_list_len > 64) |
450 | purge_addresses(); | |
ce8e922c NS |
451 | bp->b_addr = vmap(bp->b_pages, bp->b_page_count, |
452 | VM_MAP, PAGE_KERNEL); | |
453 | if (unlikely(bp->b_addr == NULL)) | |
1da177e4 | 454 | return -ENOMEM; |
ce8e922c NS |
455 | bp->b_addr += bp->b_offset; |
456 | bp->b_flags |= XBF_MAPPED; | |
1da177e4 LT |
457 | } |
458 | ||
459 | return 0; | |
460 | } | |
461 | ||
462 | /* | |
463 | * Finding and Reading Buffers | |
464 | */ | |
465 | ||
466 | /* | |
ce8e922c | 467 | * Look up, and creates if absent, a lockable buffer for |
1da177e4 LT |
468 | * a given range of an inode. The buffer is returned |
469 | * locked. If other overlapping buffers exist, they are | |
470 | * released before the new buffer is created and locked, | |
471 | * which may imply that this call will block until those buffers | |
472 | * are unlocked. No I/O is implied by this call. | |
473 | */ | |
474 | xfs_buf_t * | |
ce8e922c | 475 | _xfs_buf_find( |
1da177e4 | 476 | xfs_buftarg_t *btp, /* block device target */ |
204ab25f | 477 | xfs_off_t ioff, /* starting offset of range */ |
1da177e4 | 478 | size_t isize, /* length of range */ |
ce8e922c NS |
479 | xfs_buf_flags_t flags, |
480 | xfs_buf_t *new_bp) | |
1da177e4 | 481 | { |
204ab25f | 482 | xfs_off_t range_base; |
1da177e4 LT |
483 | size_t range_length; |
484 | xfs_bufhash_t *hash; | |
ce8e922c | 485 | xfs_buf_t *bp, *n; |
1da177e4 LT |
486 | |
487 | range_base = (ioff << BBSHIFT); | |
488 | range_length = (isize << BBSHIFT); | |
489 | ||
490 | /* Check for IOs smaller than the sector size / not sector aligned */ | |
ce8e922c | 491 | ASSERT(!(range_length < (1 << btp->bt_sshift))); |
204ab25f | 492 | ASSERT(!(range_base & (xfs_off_t)btp->bt_smask)); |
1da177e4 LT |
493 | |
494 | hash = &btp->bt_hash[hash_long((unsigned long)ioff, btp->bt_hashshift)]; | |
495 | ||
496 | spin_lock(&hash->bh_lock); | |
497 | ||
ce8e922c NS |
498 | list_for_each_entry_safe(bp, n, &hash->bh_list, b_hash_list) { |
499 | ASSERT(btp == bp->b_target); | |
500 | if (bp->b_file_offset == range_base && | |
501 | bp->b_buffer_length == range_length) { | |
1da177e4 | 502 | /* |
ce8e922c | 503 | * If we look at something, bring it to the |
1da177e4 LT |
504 | * front of the list for next time. |
505 | */ | |
ce8e922c NS |
506 | atomic_inc(&bp->b_hold); |
507 | list_move(&bp->b_hash_list, &hash->bh_list); | |
1da177e4 LT |
508 | goto found; |
509 | } | |
510 | } | |
511 | ||
512 | /* No match found */ | |
ce8e922c NS |
513 | if (new_bp) { |
514 | _xfs_buf_initialize(new_bp, btp, range_base, | |
1da177e4 | 515 | range_length, flags); |
ce8e922c NS |
516 | new_bp->b_hash = hash; |
517 | list_add(&new_bp->b_hash_list, &hash->bh_list); | |
1da177e4 | 518 | } else { |
ce8e922c | 519 | XFS_STATS_INC(xb_miss_locked); |
1da177e4 LT |
520 | } |
521 | ||
522 | spin_unlock(&hash->bh_lock); | |
ce8e922c | 523 | return new_bp; |
1da177e4 LT |
524 | |
525 | found: | |
526 | spin_unlock(&hash->bh_lock); | |
527 | ||
528 | /* Attempt to get the semaphore without sleeping, | |
529 | * if this does not work then we need to drop the | |
530 | * spinlock and do a hard attempt on the semaphore. | |
531 | */ | |
ce8e922c NS |
532 | if (down_trylock(&bp->b_sema)) { |
533 | if (!(flags & XBF_TRYLOCK)) { | |
1da177e4 | 534 | /* wait for buffer ownership */ |
ce8e922c NS |
535 | XB_TRACE(bp, "get_lock", 0); |
536 | xfs_buf_lock(bp); | |
537 | XFS_STATS_INC(xb_get_locked_waited); | |
1da177e4 LT |
538 | } else { |
539 | /* We asked for a trylock and failed, no need | |
540 | * to look at file offset and length here, we | |
ce8e922c NS |
541 | * know that this buffer at least overlaps our |
542 | * buffer and is locked, therefore our buffer | |
543 | * either does not exist, or is this buffer. | |
1da177e4 | 544 | */ |
ce8e922c NS |
545 | xfs_buf_rele(bp); |
546 | XFS_STATS_INC(xb_busy_locked); | |
547 | return NULL; | |
1da177e4 LT |
548 | } |
549 | } else { | |
550 | /* trylock worked */ | |
ce8e922c | 551 | XB_SET_OWNER(bp); |
1da177e4 LT |
552 | } |
553 | ||
ce8e922c NS |
554 | if (bp->b_flags & XBF_STALE) { |
555 | ASSERT((bp->b_flags & _XBF_DELWRI_Q) == 0); | |
556 | bp->b_flags &= XBF_MAPPED; | |
2f926587 | 557 | } |
ce8e922c NS |
558 | XB_TRACE(bp, "got_lock", 0); |
559 | XFS_STATS_INC(xb_get_locked); | |
560 | return bp; | |
1da177e4 LT |
561 | } |
562 | ||
563 | /* | |
ce8e922c | 564 | * Assembles a buffer covering the specified range. |
1da177e4 LT |
565 | * Storage in memory for all portions of the buffer will be allocated, |
566 | * although backing storage may not be. | |
567 | */ | |
568 | xfs_buf_t * | |
ce8e922c | 569 | xfs_buf_get_flags( |
1da177e4 | 570 | xfs_buftarg_t *target,/* target for buffer */ |
204ab25f | 571 | xfs_off_t ioff, /* starting offset of range */ |
1da177e4 | 572 | size_t isize, /* length of range */ |
ce8e922c | 573 | xfs_buf_flags_t flags) |
1da177e4 | 574 | { |
ce8e922c | 575 | xfs_buf_t *bp, *new_bp; |
1da177e4 LT |
576 | int error = 0, i; |
577 | ||
ce8e922c NS |
578 | new_bp = xfs_buf_allocate(flags); |
579 | if (unlikely(!new_bp)) | |
1da177e4 LT |
580 | return NULL; |
581 | ||
ce8e922c NS |
582 | bp = _xfs_buf_find(target, ioff, isize, flags, new_bp); |
583 | if (bp == new_bp) { | |
584 | error = _xfs_buf_lookup_pages(bp, flags); | |
1da177e4 LT |
585 | if (error) |
586 | goto no_buffer; | |
587 | } else { | |
ce8e922c NS |
588 | xfs_buf_deallocate(new_bp); |
589 | if (unlikely(bp == NULL)) | |
1da177e4 LT |
590 | return NULL; |
591 | } | |
592 | ||
ce8e922c NS |
593 | for (i = 0; i < bp->b_page_count; i++) |
594 | mark_page_accessed(bp->b_pages[i]); | |
1da177e4 | 595 | |
ce8e922c NS |
596 | if (!(bp->b_flags & XBF_MAPPED)) { |
597 | error = _xfs_buf_map_pages(bp, flags); | |
1da177e4 LT |
598 | if (unlikely(error)) { |
599 | printk(KERN_WARNING "%s: failed to map pages\n", | |
600 | __FUNCTION__); | |
601 | goto no_buffer; | |
602 | } | |
603 | } | |
604 | ||
ce8e922c | 605 | XFS_STATS_INC(xb_get); |
1da177e4 LT |
606 | |
607 | /* | |
608 | * Always fill in the block number now, the mapped cases can do | |
609 | * their own overlay of this later. | |
610 | */ | |
ce8e922c NS |
611 | bp->b_bn = ioff; |
612 | bp->b_count_desired = bp->b_buffer_length; | |
1da177e4 | 613 | |
ce8e922c NS |
614 | XB_TRACE(bp, "get", (unsigned long)flags); |
615 | return bp; | |
1da177e4 LT |
616 | |
617 | no_buffer: | |
ce8e922c NS |
618 | if (flags & (XBF_LOCK | XBF_TRYLOCK)) |
619 | xfs_buf_unlock(bp); | |
620 | xfs_buf_rele(bp); | |
1da177e4 LT |
621 | return NULL; |
622 | } | |
623 | ||
624 | xfs_buf_t * | |
625 | xfs_buf_read_flags( | |
626 | xfs_buftarg_t *target, | |
204ab25f | 627 | xfs_off_t ioff, |
1da177e4 | 628 | size_t isize, |
ce8e922c | 629 | xfs_buf_flags_t flags) |
1da177e4 | 630 | { |
ce8e922c NS |
631 | xfs_buf_t *bp; |
632 | ||
633 | flags |= XBF_READ; | |
634 | ||
635 | bp = xfs_buf_get_flags(target, ioff, isize, flags); | |
636 | if (bp) { | |
637 | if (!XFS_BUF_ISDONE(bp)) { | |
638 | XB_TRACE(bp, "read", (unsigned long)flags); | |
639 | XFS_STATS_INC(xb_get_read); | |
640 | xfs_buf_iostart(bp, flags); | |
641 | } else if (flags & XBF_ASYNC) { | |
642 | XB_TRACE(bp, "read_async", (unsigned long)flags); | |
1da177e4 LT |
643 | /* |
644 | * Read ahead call which is already satisfied, | |
645 | * drop the buffer | |
646 | */ | |
647 | goto no_buffer; | |
648 | } else { | |
ce8e922c | 649 | XB_TRACE(bp, "read_done", (unsigned long)flags); |
1da177e4 | 650 | /* We do not want read in the flags */ |
ce8e922c | 651 | bp->b_flags &= ~XBF_READ; |
1da177e4 LT |
652 | } |
653 | } | |
654 | ||
ce8e922c | 655 | return bp; |
1da177e4 LT |
656 | |
657 | no_buffer: | |
ce8e922c NS |
658 | if (flags & (XBF_LOCK | XBF_TRYLOCK)) |
659 | xfs_buf_unlock(bp); | |
660 | xfs_buf_rele(bp); | |
1da177e4 LT |
661 | return NULL; |
662 | } | |
663 | ||
1da177e4 | 664 | /* |
ce8e922c NS |
665 | * If we are not low on memory then do the readahead in a deadlock |
666 | * safe manner. | |
1da177e4 LT |
667 | */ |
668 | void | |
ce8e922c | 669 | xfs_buf_readahead( |
1da177e4 | 670 | xfs_buftarg_t *target, |
204ab25f | 671 | xfs_off_t ioff, |
1da177e4 | 672 | size_t isize, |
ce8e922c | 673 | xfs_buf_flags_t flags) |
1da177e4 LT |
674 | { |
675 | struct backing_dev_info *bdi; | |
676 | ||
ce8e922c | 677 | bdi = target->bt_mapping->backing_dev_info; |
1da177e4 LT |
678 | if (bdi_read_congested(bdi)) |
679 | return; | |
680 | ||
ce8e922c | 681 | flags |= (XBF_TRYLOCK|XBF_ASYNC|XBF_READ_AHEAD); |
1da177e4 LT |
682 | xfs_buf_read_flags(target, ioff, isize, flags); |
683 | } | |
684 | ||
685 | xfs_buf_t * | |
ce8e922c | 686 | xfs_buf_get_empty( |
1da177e4 LT |
687 | size_t len, |
688 | xfs_buftarg_t *target) | |
689 | { | |
ce8e922c | 690 | xfs_buf_t *bp; |
1da177e4 | 691 | |
ce8e922c NS |
692 | bp = xfs_buf_allocate(0); |
693 | if (bp) | |
694 | _xfs_buf_initialize(bp, target, 0, len, 0); | |
695 | return bp; | |
1da177e4 LT |
696 | } |
697 | ||
698 | static inline struct page * | |
699 | mem_to_page( | |
700 | void *addr) | |
701 | { | |
702 | if (((unsigned long)addr < VMALLOC_START) || | |
703 | ((unsigned long)addr >= VMALLOC_END)) { | |
704 | return virt_to_page(addr); | |
705 | } else { | |
706 | return vmalloc_to_page(addr); | |
707 | } | |
708 | } | |
709 | ||
710 | int | |
ce8e922c NS |
711 | xfs_buf_associate_memory( |
712 | xfs_buf_t *bp, | |
1da177e4 LT |
713 | void *mem, |
714 | size_t len) | |
715 | { | |
716 | int rval; | |
717 | int i = 0; | |
718 | size_t ptr; | |
719 | size_t end, end_cur; | |
720 | off_t offset; | |
721 | int page_count; | |
722 | ||
723 | page_count = PAGE_CACHE_ALIGN(len) >> PAGE_CACHE_SHIFT; | |
724 | offset = (off_t) mem - ((off_t)mem & PAGE_CACHE_MASK); | |
725 | if (offset && (len > PAGE_CACHE_SIZE)) | |
726 | page_count++; | |
727 | ||
728 | /* Free any previous set of page pointers */ | |
ce8e922c NS |
729 | if (bp->b_pages) |
730 | _xfs_buf_free_pages(bp); | |
1da177e4 | 731 | |
ce8e922c NS |
732 | bp->b_pages = NULL; |
733 | bp->b_addr = mem; | |
1da177e4 | 734 | |
ce8e922c | 735 | rval = _xfs_buf_get_pages(bp, page_count, 0); |
1da177e4 LT |
736 | if (rval) |
737 | return rval; | |
738 | ||
ce8e922c | 739 | bp->b_offset = offset; |
1da177e4 LT |
740 | ptr = (size_t) mem & PAGE_CACHE_MASK; |
741 | end = PAGE_CACHE_ALIGN((size_t) mem + len); | |
742 | end_cur = end; | |
743 | /* set up first page */ | |
ce8e922c | 744 | bp->b_pages[0] = mem_to_page(mem); |
1da177e4 LT |
745 | |
746 | ptr += PAGE_CACHE_SIZE; | |
ce8e922c | 747 | bp->b_page_count = ++i; |
1da177e4 | 748 | while (ptr < end) { |
ce8e922c NS |
749 | bp->b_pages[i] = mem_to_page((void *)ptr); |
750 | bp->b_page_count = ++i; | |
1da177e4 LT |
751 | ptr += PAGE_CACHE_SIZE; |
752 | } | |
ce8e922c | 753 | bp->b_locked = 0; |
1da177e4 | 754 | |
ce8e922c NS |
755 | bp->b_count_desired = bp->b_buffer_length = len; |
756 | bp->b_flags |= XBF_MAPPED; | |
1da177e4 LT |
757 | |
758 | return 0; | |
759 | } | |
760 | ||
761 | xfs_buf_t * | |
ce8e922c | 762 | xfs_buf_get_noaddr( |
1da177e4 LT |
763 | size_t len, |
764 | xfs_buftarg_t *target) | |
765 | { | |
766 | size_t malloc_len = len; | |
767 | xfs_buf_t *bp; | |
768 | void *data; | |
769 | int error; | |
770 | ||
ce8e922c | 771 | bp = xfs_buf_allocate(0); |
1da177e4 LT |
772 | if (unlikely(bp == NULL)) |
773 | goto fail; | |
ce8e922c | 774 | _xfs_buf_initialize(bp, target, 0, len, 0); |
1da177e4 LT |
775 | |
776 | try_again: | |
efb8ad7e | 777 | data = kmem_alloc(malloc_len, KM_SLEEP | KM_MAYFAIL | KM_LARGE); |
1da177e4 LT |
778 | if (unlikely(data == NULL)) |
779 | goto fail_free_buf; | |
780 | ||
781 | /* check whether alignment matches.. */ | |
782 | if ((__psunsigned_t)data != | |
ce8e922c | 783 | ((__psunsigned_t)data & ~target->bt_smask)) { |
1da177e4 LT |
784 | /* .. else double the size and try again */ |
785 | kmem_free(data, malloc_len); | |
786 | malloc_len <<= 1; | |
787 | goto try_again; | |
788 | } | |
789 | ||
ce8e922c | 790 | error = xfs_buf_associate_memory(bp, data, len); |
1da177e4 LT |
791 | if (error) |
792 | goto fail_free_mem; | |
ce8e922c | 793 | bp->b_flags |= _XBF_KMEM_ALLOC; |
1da177e4 | 794 | |
ce8e922c | 795 | xfs_buf_unlock(bp); |
1da177e4 | 796 | |
ce8e922c | 797 | XB_TRACE(bp, "no_daddr", data); |
1da177e4 LT |
798 | return bp; |
799 | fail_free_mem: | |
800 | kmem_free(data, malloc_len); | |
801 | fail_free_buf: | |
ce8e922c | 802 | xfs_buf_free(bp); |
1da177e4 LT |
803 | fail: |
804 | return NULL; | |
805 | } | |
806 | ||
807 | /* | |
1da177e4 LT |
808 | * Increment reference count on buffer, to hold the buffer concurrently |
809 | * with another thread which may release (free) the buffer asynchronously. | |
1da177e4 LT |
810 | * Must hold the buffer already to call this function. |
811 | */ | |
812 | void | |
ce8e922c NS |
813 | xfs_buf_hold( |
814 | xfs_buf_t *bp) | |
1da177e4 | 815 | { |
ce8e922c NS |
816 | atomic_inc(&bp->b_hold); |
817 | XB_TRACE(bp, "hold", 0); | |
1da177e4 LT |
818 | } |
819 | ||
820 | /* | |
ce8e922c NS |
821 | * Releases a hold on the specified buffer. If the |
822 | * the hold count is 1, calls xfs_buf_free. | |
1da177e4 LT |
823 | */ |
824 | void | |
ce8e922c NS |
825 | xfs_buf_rele( |
826 | xfs_buf_t *bp) | |
1da177e4 | 827 | { |
ce8e922c | 828 | xfs_bufhash_t *hash = bp->b_hash; |
1da177e4 | 829 | |
ce8e922c | 830 | XB_TRACE(bp, "rele", bp->b_relse); |
1da177e4 | 831 | |
fad3aa1e NS |
832 | if (unlikely(!hash)) { |
833 | ASSERT(!bp->b_relse); | |
834 | if (atomic_dec_and_test(&bp->b_hold)) | |
835 | xfs_buf_free(bp); | |
836 | return; | |
837 | } | |
838 | ||
ce8e922c NS |
839 | if (atomic_dec_and_lock(&bp->b_hold, &hash->bh_lock)) { |
840 | if (bp->b_relse) { | |
841 | atomic_inc(&bp->b_hold); | |
1da177e4 | 842 | spin_unlock(&hash->bh_lock); |
ce8e922c NS |
843 | (*(bp->b_relse)) (bp); |
844 | } else if (bp->b_flags & XBF_FS_MANAGED) { | |
1da177e4 | 845 | spin_unlock(&hash->bh_lock); |
1da177e4 | 846 | } else { |
ce8e922c NS |
847 | ASSERT(!(bp->b_flags & (XBF_DELWRI|_XBF_DELWRI_Q))); |
848 | list_del_init(&bp->b_hash_list); | |
1da177e4 | 849 | spin_unlock(&hash->bh_lock); |
ce8e922c | 850 | xfs_buf_free(bp); |
1da177e4 | 851 | } |
2f926587 DC |
852 | } else { |
853 | /* | |
854 | * Catch reference count leaks | |
855 | */ | |
ce8e922c | 856 | ASSERT(atomic_read(&bp->b_hold) >= 0); |
1da177e4 LT |
857 | } |
858 | } | |
859 | ||
860 | ||
861 | /* | |
862 | * Mutual exclusion on buffers. Locking model: | |
863 | * | |
864 | * Buffers associated with inodes for which buffer locking | |
865 | * is not enabled are not protected by semaphores, and are | |
866 | * assumed to be exclusively owned by the caller. There is a | |
867 | * spinlock in the buffer, used by the caller when concurrent | |
868 | * access is possible. | |
869 | */ | |
870 | ||
871 | /* | |
ce8e922c NS |
872 | * Locks a buffer object, if it is not already locked. |
873 | * Note that this in no way locks the underlying pages, so it is only | |
874 | * useful for synchronizing concurrent use of buffer objects, not for | |
875 | * synchronizing independent access to the underlying pages. | |
1da177e4 LT |
876 | */ |
877 | int | |
ce8e922c NS |
878 | xfs_buf_cond_lock( |
879 | xfs_buf_t *bp) | |
1da177e4 LT |
880 | { |
881 | int locked; | |
882 | ||
ce8e922c | 883 | locked = down_trylock(&bp->b_sema) == 0; |
1da177e4 | 884 | if (locked) { |
ce8e922c | 885 | XB_SET_OWNER(bp); |
1da177e4 | 886 | } |
ce8e922c NS |
887 | XB_TRACE(bp, "cond_lock", (long)locked); |
888 | return locked ? 0 : -EBUSY; | |
1da177e4 LT |
889 | } |
890 | ||
891 | #if defined(DEBUG) || defined(XFS_BLI_TRACE) | |
1da177e4 | 892 | int |
ce8e922c NS |
893 | xfs_buf_lock_value( |
894 | xfs_buf_t *bp) | |
1da177e4 | 895 | { |
ce8e922c | 896 | return atomic_read(&bp->b_sema.count); |
1da177e4 LT |
897 | } |
898 | #endif | |
899 | ||
900 | /* | |
ce8e922c NS |
901 | * Locks a buffer object. |
902 | * Note that this in no way locks the underlying pages, so it is only | |
903 | * useful for synchronizing concurrent use of buffer objects, not for | |
904 | * synchronizing independent access to the underlying pages. | |
1da177e4 | 905 | */ |
ce8e922c NS |
906 | void |
907 | xfs_buf_lock( | |
908 | xfs_buf_t *bp) | |
1da177e4 | 909 | { |
ce8e922c NS |
910 | XB_TRACE(bp, "lock", 0); |
911 | if (atomic_read(&bp->b_io_remaining)) | |
912 | blk_run_address_space(bp->b_target->bt_mapping); | |
913 | down(&bp->b_sema); | |
914 | XB_SET_OWNER(bp); | |
915 | XB_TRACE(bp, "locked", 0); | |
1da177e4 LT |
916 | } |
917 | ||
918 | /* | |
ce8e922c | 919 | * Releases the lock on the buffer object. |
2f926587 | 920 | * If the buffer is marked delwri but is not queued, do so before we |
ce8e922c | 921 | * unlock the buffer as we need to set flags correctly. We also need to |
2f926587 DC |
922 | * take a reference for the delwri queue because the unlocker is going to |
923 | * drop their's and they don't know we just queued it. | |
1da177e4 LT |
924 | */ |
925 | void | |
ce8e922c NS |
926 | xfs_buf_unlock( |
927 | xfs_buf_t *bp) | |
1da177e4 | 928 | { |
ce8e922c NS |
929 | if ((bp->b_flags & (XBF_DELWRI|_XBF_DELWRI_Q)) == XBF_DELWRI) { |
930 | atomic_inc(&bp->b_hold); | |
931 | bp->b_flags |= XBF_ASYNC; | |
932 | xfs_buf_delwri_queue(bp, 0); | |
2f926587 DC |
933 | } |
934 | ||
ce8e922c NS |
935 | XB_CLEAR_OWNER(bp); |
936 | up(&bp->b_sema); | |
937 | XB_TRACE(bp, "unlock", 0); | |
1da177e4 LT |
938 | } |
939 | ||
940 | ||
941 | /* | |
942 | * Pinning Buffer Storage in Memory | |
ce8e922c | 943 | * Ensure that no attempt to force a buffer to disk will succeed. |
1da177e4 LT |
944 | */ |
945 | void | |
ce8e922c NS |
946 | xfs_buf_pin( |
947 | xfs_buf_t *bp) | |
1da177e4 | 948 | { |
ce8e922c NS |
949 | atomic_inc(&bp->b_pin_count); |
950 | XB_TRACE(bp, "pin", (long)bp->b_pin_count.counter); | |
1da177e4 LT |
951 | } |
952 | ||
1da177e4 | 953 | void |
ce8e922c NS |
954 | xfs_buf_unpin( |
955 | xfs_buf_t *bp) | |
1da177e4 | 956 | { |
ce8e922c NS |
957 | if (atomic_dec_and_test(&bp->b_pin_count)) |
958 | wake_up_all(&bp->b_waiters); | |
959 | XB_TRACE(bp, "unpin", (long)bp->b_pin_count.counter); | |
1da177e4 LT |
960 | } |
961 | ||
962 | int | |
ce8e922c NS |
963 | xfs_buf_ispin( |
964 | xfs_buf_t *bp) | |
1da177e4 | 965 | { |
ce8e922c | 966 | return atomic_read(&bp->b_pin_count); |
1da177e4 LT |
967 | } |
968 | ||
ce8e922c NS |
969 | STATIC void |
970 | xfs_buf_wait_unpin( | |
971 | xfs_buf_t *bp) | |
1da177e4 LT |
972 | { |
973 | DECLARE_WAITQUEUE (wait, current); | |
974 | ||
ce8e922c | 975 | if (atomic_read(&bp->b_pin_count) == 0) |
1da177e4 LT |
976 | return; |
977 | ||
ce8e922c | 978 | add_wait_queue(&bp->b_waiters, &wait); |
1da177e4 LT |
979 | for (;;) { |
980 | set_current_state(TASK_UNINTERRUPTIBLE); | |
ce8e922c | 981 | if (atomic_read(&bp->b_pin_count) == 0) |
1da177e4 | 982 | break; |
ce8e922c NS |
983 | if (atomic_read(&bp->b_io_remaining)) |
984 | blk_run_address_space(bp->b_target->bt_mapping); | |
1da177e4 LT |
985 | schedule(); |
986 | } | |
ce8e922c | 987 | remove_wait_queue(&bp->b_waiters, &wait); |
1da177e4 LT |
988 | set_current_state(TASK_RUNNING); |
989 | } | |
990 | ||
991 | /* | |
992 | * Buffer Utility Routines | |
993 | */ | |
994 | ||
1da177e4 | 995 | STATIC void |
ce8e922c | 996 | xfs_buf_iodone_work( |
1da177e4 LT |
997 | void *v) |
998 | { | |
999 | xfs_buf_t *bp = (xfs_buf_t *)v; | |
1000 | ||
ce8e922c NS |
1001 | if (bp->b_iodone) |
1002 | (*(bp->b_iodone))(bp); | |
1003 | else if (bp->b_flags & XBF_ASYNC) | |
1da177e4 LT |
1004 | xfs_buf_relse(bp); |
1005 | } | |
1006 | ||
1007 | void | |
ce8e922c NS |
1008 | xfs_buf_ioend( |
1009 | xfs_buf_t *bp, | |
1da177e4 LT |
1010 | int schedule) |
1011 | { | |
ce8e922c NS |
1012 | bp->b_flags &= ~(XBF_READ | XBF_WRITE); |
1013 | if (bp->b_error == 0) | |
1014 | bp->b_flags |= XBF_DONE; | |
1da177e4 | 1015 | |
ce8e922c | 1016 | XB_TRACE(bp, "iodone", bp->b_iodone); |
1da177e4 | 1017 | |
ce8e922c | 1018 | if ((bp->b_iodone) || (bp->b_flags & XBF_ASYNC)) { |
1da177e4 | 1019 | if (schedule) { |
ce8e922c NS |
1020 | INIT_WORK(&bp->b_iodone_work, xfs_buf_iodone_work, bp); |
1021 | queue_work(xfslogd_workqueue, &bp->b_iodone_work); | |
1da177e4 | 1022 | } else { |
ce8e922c | 1023 | xfs_buf_iodone_work(bp); |
1da177e4 LT |
1024 | } |
1025 | } else { | |
ce8e922c | 1026 | up(&bp->b_iodonesema); |
1da177e4 LT |
1027 | } |
1028 | } | |
1029 | ||
1da177e4 | 1030 | void |
ce8e922c NS |
1031 | xfs_buf_ioerror( |
1032 | xfs_buf_t *bp, | |
1033 | int error) | |
1da177e4 LT |
1034 | { |
1035 | ASSERT(error >= 0 && error <= 0xffff); | |
ce8e922c NS |
1036 | bp->b_error = (unsigned short)error; |
1037 | XB_TRACE(bp, "ioerror", (unsigned long)error); | |
1da177e4 LT |
1038 | } |
1039 | ||
1040 | /* | |
ce8e922c NS |
1041 | * Initiate I/O on a buffer, based on the flags supplied. |
1042 | * The b_iodone routine in the buffer supplied will only be called | |
1da177e4 | 1043 | * when all of the subsidiary I/O requests, if any, have been completed. |
1da177e4 LT |
1044 | */ |
1045 | int | |
ce8e922c NS |
1046 | xfs_buf_iostart( |
1047 | xfs_buf_t *bp, | |
1048 | xfs_buf_flags_t flags) | |
1da177e4 LT |
1049 | { |
1050 | int status = 0; | |
1051 | ||
ce8e922c | 1052 | XB_TRACE(bp, "iostart", (unsigned long)flags); |
1da177e4 | 1053 | |
ce8e922c NS |
1054 | if (flags & XBF_DELWRI) { |
1055 | bp->b_flags &= ~(XBF_READ | XBF_WRITE | XBF_ASYNC); | |
1056 | bp->b_flags |= flags & (XBF_DELWRI | XBF_ASYNC); | |
1057 | xfs_buf_delwri_queue(bp, 1); | |
1da177e4 LT |
1058 | return status; |
1059 | } | |
1060 | ||
ce8e922c NS |
1061 | bp->b_flags &= ~(XBF_READ | XBF_WRITE | XBF_ASYNC | XBF_DELWRI | \ |
1062 | XBF_READ_AHEAD | _XBF_RUN_QUEUES); | |
1063 | bp->b_flags |= flags & (XBF_READ | XBF_WRITE | XBF_ASYNC | \ | |
1064 | XBF_READ_AHEAD | _XBF_RUN_QUEUES); | |
1da177e4 | 1065 | |
ce8e922c | 1066 | BUG_ON(bp->b_bn == XFS_BUF_DADDR_NULL); |
1da177e4 LT |
1067 | |
1068 | /* For writes allow an alternate strategy routine to precede | |
1069 | * the actual I/O request (which may not be issued at all in | |
1070 | * a shutdown situation, for example). | |
1071 | */ | |
ce8e922c NS |
1072 | status = (flags & XBF_WRITE) ? |
1073 | xfs_buf_iostrategy(bp) : xfs_buf_iorequest(bp); | |
1da177e4 LT |
1074 | |
1075 | /* Wait for I/O if we are not an async request. | |
1076 | * Note: async I/O request completion will release the buffer, | |
1077 | * and that can already be done by this point. So using the | |
1078 | * buffer pointer from here on, after async I/O, is invalid. | |
1079 | */ | |
ce8e922c NS |
1080 | if (!status && !(flags & XBF_ASYNC)) |
1081 | status = xfs_buf_iowait(bp); | |
1da177e4 LT |
1082 | |
1083 | return status; | |
1084 | } | |
1085 | ||
1da177e4 | 1086 | STATIC __inline__ int |
ce8e922c NS |
1087 | _xfs_buf_iolocked( |
1088 | xfs_buf_t *bp) | |
1da177e4 | 1089 | { |
ce8e922c NS |
1090 | ASSERT(bp->b_flags & (XBF_READ | XBF_WRITE)); |
1091 | if (bp->b_flags & XBF_READ) | |
1092 | return bp->b_locked; | |
1da177e4 LT |
1093 | return 0; |
1094 | } | |
1095 | ||
1096 | STATIC __inline__ void | |
ce8e922c NS |
1097 | _xfs_buf_ioend( |
1098 | xfs_buf_t *bp, | |
1da177e4 LT |
1099 | int schedule) |
1100 | { | |
ce8e922c NS |
1101 | if (atomic_dec_and_test(&bp->b_io_remaining) == 1) { |
1102 | bp->b_locked = 0; | |
1103 | xfs_buf_ioend(bp, schedule); | |
1da177e4 LT |
1104 | } |
1105 | } | |
1106 | ||
1107 | STATIC int | |
ce8e922c | 1108 | xfs_buf_bio_end_io( |
1da177e4 LT |
1109 | struct bio *bio, |
1110 | unsigned int bytes_done, | |
1111 | int error) | |
1112 | { | |
ce8e922c NS |
1113 | xfs_buf_t *bp = (xfs_buf_t *)bio->bi_private; |
1114 | unsigned int blocksize = bp->b_target->bt_bsize; | |
eedb5530 | 1115 | struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1; |
1da177e4 LT |
1116 | |
1117 | if (bio->bi_size) | |
1118 | return 1; | |
1119 | ||
1120 | if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) | |
ce8e922c | 1121 | bp->b_error = EIO; |
1da177e4 | 1122 | |
eedb5530 | 1123 | do { |
1da177e4 LT |
1124 | struct page *page = bvec->bv_page; |
1125 | ||
948ecdb4 | 1126 | ASSERT(!PagePrivate(page)); |
ce8e922c NS |
1127 | if (unlikely(bp->b_error)) { |
1128 | if (bp->b_flags & XBF_READ) | |
eedb5530 | 1129 | ClearPageUptodate(page); |
ce8e922c | 1130 | } else if (blocksize >= PAGE_CACHE_SIZE) { |
1da177e4 LT |
1131 | SetPageUptodate(page); |
1132 | } else if (!PagePrivate(page) && | |
ce8e922c | 1133 | (bp->b_flags & _XBF_PAGE_CACHE)) { |
1da177e4 LT |
1134 | set_page_region(page, bvec->bv_offset, bvec->bv_len); |
1135 | } | |
1136 | ||
eedb5530 NS |
1137 | if (--bvec >= bio->bi_io_vec) |
1138 | prefetchw(&bvec->bv_page->flags); | |
1139 | ||
ce8e922c | 1140 | if (_xfs_buf_iolocked(bp)) { |
1da177e4 LT |
1141 | unlock_page(page); |
1142 | } | |
eedb5530 | 1143 | } while (bvec >= bio->bi_io_vec); |
1da177e4 | 1144 | |
ce8e922c | 1145 | _xfs_buf_ioend(bp, 1); |
1da177e4 LT |
1146 | bio_put(bio); |
1147 | return 0; | |
1148 | } | |
1149 | ||
1150 | STATIC void | |
ce8e922c NS |
1151 | _xfs_buf_ioapply( |
1152 | xfs_buf_t *bp) | |
1da177e4 LT |
1153 | { |
1154 | int i, rw, map_i, total_nr_pages, nr_pages; | |
1155 | struct bio *bio; | |
ce8e922c NS |
1156 | int offset = bp->b_offset; |
1157 | int size = bp->b_count_desired; | |
1158 | sector_t sector = bp->b_bn; | |
1159 | unsigned int blocksize = bp->b_target->bt_bsize; | |
1160 | int locking = _xfs_buf_iolocked(bp); | |
1da177e4 | 1161 | |
ce8e922c | 1162 | total_nr_pages = bp->b_page_count; |
1da177e4 LT |
1163 | map_i = 0; |
1164 | ||
ce8e922c NS |
1165 | if (bp->b_flags & XBF_ORDERED) { |
1166 | ASSERT(!(bp->b_flags & XBF_READ)); | |
f538d4da | 1167 | rw = WRITE_BARRIER; |
51bdd706 NS |
1168 | } else if (bp->b_flags & _XBF_RUN_QUEUES) { |
1169 | ASSERT(!(bp->b_flags & XBF_READ_AHEAD)); | |
1170 | bp->b_flags &= ~_XBF_RUN_QUEUES; | |
1171 | rw = (bp->b_flags & XBF_WRITE) ? WRITE_SYNC : READ_SYNC; | |
1172 | } else { | |
1173 | rw = (bp->b_flags & XBF_WRITE) ? WRITE : | |
1174 | (bp->b_flags & XBF_READ_AHEAD) ? READA : READ; | |
f538d4da CH |
1175 | } |
1176 | ||
ce8e922c | 1177 | /* Special code path for reading a sub page size buffer in -- |
1da177e4 LT |
1178 | * we populate up the whole page, and hence the other metadata |
1179 | * in the same page. This optimization is only valid when the | |
ce8e922c | 1180 | * filesystem block size is not smaller than the page size. |
1da177e4 | 1181 | */ |
ce8e922c NS |
1182 | if ((bp->b_buffer_length < PAGE_CACHE_SIZE) && |
1183 | (bp->b_flags & XBF_READ) && locking && | |
1184 | (blocksize >= PAGE_CACHE_SIZE)) { | |
1da177e4 LT |
1185 | bio = bio_alloc(GFP_NOIO, 1); |
1186 | ||
ce8e922c | 1187 | bio->bi_bdev = bp->b_target->bt_bdev; |
1da177e4 | 1188 | bio->bi_sector = sector - (offset >> BBSHIFT); |
ce8e922c NS |
1189 | bio->bi_end_io = xfs_buf_bio_end_io; |
1190 | bio->bi_private = bp; | |
1da177e4 | 1191 | |
ce8e922c | 1192 | bio_add_page(bio, bp->b_pages[0], PAGE_CACHE_SIZE, 0); |
1da177e4 LT |
1193 | size = 0; |
1194 | ||
ce8e922c | 1195 | atomic_inc(&bp->b_io_remaining); |
1da177e4 LT |
1196 | |
1197 | goto submit_io; | |
1198 | } | |
1199 | ||
1200 | /* Lock down the pages which we need to for the request */ | |
ce8e922c | 1201 | if (locking && (bp->b_flags & XBF_WRITE) && (bp->b_locked == 0)) { |
1da177e4 LT |
1202 | for (i = 0; size; i++) { |
1203 | int nbytes = PAGE_CACHE_SIZE - offset; | |
ce8e922c | 1204 | struct page *page = bp->b_pages[i]; |
1da177e4 LT |
1205 | |
1206 | if (nbytes > size) | |
1207 | nbytes = size; | |
1208 | ||
1209 | lock_page(page); | |
1210 | ||
1211 | size -= nbytes; | |
1212 | offset = 0; | |
1213 | } | |
ce8e922c NS |
1214 | offset = bp->b_offset; |
1215 | size = bp->b_count_desired; | |
1da177e4 LT |
1216 | } |
1217 | ||
1218 | next_chunk: | |
ce8e922c | 1219 | atomic_inc(&bp->b_io_remaining); |
1da177e4 LT |
1220 | nr_pages = BIO_MAX_SECTORS >> (PAGE_SHIFT - BBSHIFT); |
1221 | if (nr_pages > total_nr_pages) | |
1222 | nr_pages = total_nr_pages; | |
1223 | ||
1224 | bio = bio_alloc(GFP_NOIO, nr_pages); | |
ce8e922c | 1225 | bio->bi_bdev = bp->b_target->bt_bdev; |
1da177e4 | 1226 | bio->bi_sector = sector; |
ce8e922c NS |
1227 | bio->bi_end_io = xfs_buf_bio_end_io; |
1228 | bio->bi_private = bp; | |
1da177e4 LT |
1229 | |
1230 | for (; size && nr_pages; nr_pages--, map_i++) { | |
ce8e922c | 1231 | int rbytes, nbytes = PAGE_CACHE_SIZE - offset; |
1da177e4 LT |
1232 | |
1233 | if (nbytes > size) | |
1234 | nbytes = size; | |
1235 | ||
ce8e922c NS |
1236 | rbytes = bio_add_page(bio, bp->b_pages[map_i], nbytes, offset); |
1237 | if (rbytes < nbytes) | |
1da177e4 LT |
1238 | break; |
1239 | ||
1240 | offset = 0; | |
1241 | sector += nbytes >> BBSHIFT; | |
1242 | size -= nbytes; | |
1243 | total_nr_pages--; | |
1244 | } | |
1245 | ||
1246 | submit_io: | |
1247 | if (likely(bio->bi_size)) { | |
1248 | submit_bio(rw, bio); | |
1249 | if (size) | |
1250 | goto next_chunk; | |
1251 | } else { | |
1252 | bio_put(bio); | |
ce8e922c | 1253 | xfs_buf_ioerror(bp, EIO); |
1da177e4 LT |
1254 | } |
1255 | } | |
1256 | ||
1da177e4 | 1257 | int |
ce8e922c NS |
1258 | xfs_buf_iorequest( |
1259 | xfs_buf_t *bp) | |
1da177e4 | 1260 | { |
ce8e922c | 1261 | XB_TRACE(bp, "iorequest", 0); |
1da177e4 | 1262 | |
ce8e922c NS |
1263 | if (bp->b_flags & XBF_DELWRI) { |
1264 | xfs_buf_delwri_queue(bp, 1); | |
1da177e4 LT |
1265 | return 0; |
1266 | } | |
1267 | ||
ce8e922c NS |
1268 | if (bp->b_flags & XBF_WRITE) { |
1269 | xfs_buf_wait_unpin(bp); | |
1da177e4 LT |
1270 | } |
1271 | ||
ce8e922c | 1272 | xfs_buf_hold(bp); |
1da177e4 LT |
1273 | |
1274 | /* Set the count to 1 initially, this will stop an I/O | |
1275 | * completion callout which happens before we have started | |
ce8e922c | 1276 | * all the I/O from calling xfs_buf_ioend too early. |
1da177e4 | 1277 | */ |
ce8e922c NS |
1278 | atomic_set(&bp->b_io_remaining, 1); |
1279 | _xfs_buf_ioapply(bp); | |
1280 | _xfs_buf_ioend(bp, 0); | |
1da177e4 | 1281 | |
ce8e922c | 1282 | xfs_buf_rele(bp); |
1da177e4 LT |
1283 | return 0; |
1284 | } | |
1285 | ||
1286 | /* | |
ce8e922c NS |
1287 | * Waits for I/O to complete on the buffer supplied. |
1288 | * It returns immediately if no I/O is pending. | |
1289 | * It returns the I/O error code, if any, or 0 if there was no error. | |
1da177e4 LT |
1290 | */ |
1291 | int | |
ce8e922c NS |
1292 | xfs_buf_iowait( |
1293 | xfs_buf_t *bp) | |
1da177e4 | 1294 | { |
ce8e922c NS |
1295 | XB_TRACE(bp, "iowait", 0); |
1296 | if (atomic_read(&bp->b_io_remaining)) | |
1297 | blk_run_address_space(bp->b_target->bt_mapping); | |
1298 | down(&bp->b_iodonesema); | |
1299 | XB_TRACE(bp, "iowaited", (long)bp->b_error); | |
1300 | return bp->b_error; | |
1da177e4 LT |
1301 | } |
1302 | ||
ce8e922c NS |
1303 | xfs_caddr_t |
1304 | xfs_buf_offset( | |
1305 | xfs_buf_t *bp, | |
1da177e4 LT |
1306 | size_t offset) |
1307 | { | |
1308 | struct page *page; | |
1309 | ||
ce8e922c NS |
1310 | if (bp->b_flags & XBF_MAPPED) |
1311 | return XFS_BUF_PTR(bp) + offset; | |
1da177e4 | 1312 | |
ce8e922c NS |
1313 | offset += bp->b_offset; |
1314 | page = bp->b_pages[offset >> PAGE_CACHE_SHIFT]; | |
1315 | return (xfs_caddr_t)page_address(page) + (offset & (PAGE_CACHE_SIZE-1)); | |
1da177e4 LT |
1316 | } |
1317 | ||
1318 | /* | |
1da177e4 LT |
1319 | * Move data into or out of a buffer. |
1320 | */ | |
1321 | void | |
ce8e922c NS |
1322 | xfs_buf_iomove( |
1323 | xfs_buf_t *bp, /* buffer to process */ | |
1da177e4 LT |
1324 | size_t boff, /* starting buffer offset */ |
1325 | size_t bsize, /* length to copy */ | |
1326 | caddr_t data, /* data address */ | |
ce8e922c | 1327 | xfs_buf_rw_t mode) /* read/write/zero flag */ |
1da177e4 LT |
1328 | { |
1329 | size_t bend, cpoff, csize; | |
1330 | struct page *page; | |
1331 | ||
1332 | bend = boff + bsize; | |
1333 | while (boff < bend) { | |
ce8e922c NS |
1334 | page = bp->b_pages[xfs_buf_btoct(boff + bp->b_offset)]; |
1335 | cpoff = xfs_buf_poff(boff + bp->b_offset); | |
1da177e4 | 1336 | csize = min_t(size_t, |
ce8e922c | 1337 | PAGE_CACHE_SIZE-cpoff, bp->b_count_desired-boff); |
1da177e4 LT |
1338 | |
1339 | ASSERT(((csize + cpoff) <= PAGE_CACHE_SIZE)); | |
1340 | ||
1341 | switch (mode) { | |
ce8e922c | 1342 | case XBRW_ZERO: |
1da177e4 LT |
1343 | memset(page_address(page) + cpoff, 0, csize); |
1344 | break; | |
ce8e922c | 1345 | case XBRW_READ: |
1da177e4 LT |
1346 | memcpy(data, page_address(page) + cpoff, csize); |
1347 | break; | |
ce8e922c | 1348 | case XBRW_WRITE: |
1da177e4 LT |
1349 | memcpy(page_address(page) + cpoff, data, csize); |
1350 | } | |
1351 | ||
1352 | boff += csize; | |
1353 | data += csize; | |
1354 | } | |
1355 | } | |
1356 | ||
1357 | /* | |
ce8e922c | 1358 | * Handling of buffer targets (buftargs). |
1da177e4 LT |
1359 | */ |
1360 | ||
1361 | /* | |
ce8e922c NS |
1362 | * Wait for any bufs with callbacks that have been submitted but |
1363 | * have not yet returned... walk the hash list for the target. | |
1da177e4 LT |
1364 | */ |
1365 | void | |
1366 | xfs_wait_buftarg( | |
1367 | xfs_buftarg_t *btp) | |
1368 | { | |
1369 | xfs_buf_t *bp, *n; | |
1370 | xfs_bufhash_t *hash; | |
1371 | uint i; | |
1372 | ||
1373 | for (i = 0; i < (1 << btp->bt_hashshift); i++) { | |
1374 | hash = &btp->bt_hash[i]; | |
1375 | again: | |
1376 | spin_lock(&hash->bh_lock); | |
ce8e922c NS |
1377 | list_for_each_entry_safe(bp, n, &hash->bh_list, b_hash_list) { |
1378 | ASSERT(btp == bp->b_target); | |
1379 | if (!(bp->b_flags & XBF_FS_MANAGED)) { | |
1da177e4 | 1380 | spin_unlock(&hash->bh_lock); |
2f926587 DC |
1381 | /* |
1382 | * Catch superblock reference count leaks | |
1383 | * immediately | |
1384 | */ | |
ce8e922c | 1385 | BUG_ON(bp->b_bn == 0); |
1da177e4 LT |
1386 | delay(100); |
1387 | goto again; | |
1388 | } | |
1389 | } | |
1390 | spin_unlock(&hash->bh_lock); | |
1391 | } | |
1392 | } | |
1393 | ||
1394 | /* | |
ce8e922c NS |
1395 | * Allocate buffer hash table for a given target. |
1396 | * For devices containing metadata (i.e. not the log/realtime devices) | |
1397 | * we need to allocate a much larger hash table. | |
1da177e4 LT |
1398 | */ |
1399 | STATIC void | |
1400 | xfs_alloc_bufhash( | |
1401 | xfs_buftarg_t *btp, | |
1402 | int external) | |
1403 | { | |
1404 | unsigned int i; | |
1405 | ||
1406 | btp->bt_hashshift = external ? 3 : 8; /* 8 or 256 buckets */ | |
1407 | btp->bt_hashmask = (1 << btp->bt_hashshift) - 1; | |
1408 | btp->bt_hash = kmem_zalloc((1 << btp->bt_hashshift) * | |
93c189c1 | 1409 | sizeof(xfs_bufhash_t), KM_SLEEP | KM_LARGE); |
1da177e4 LT |
1410 | for (i = 0; i < (1 << btp->bt_hashshift); i++) { |
1411 | spin_lock_init(&btp->bt_hash[i].bh_lock); | |
1412 | INIT_LIST_HEAD(&btp->bt_hash[i].bh_list); | |
1413 | } | |
1414 | } | |
1415 | ||
1416 | STATIC void | |
1417 | xfs_free_bufhash( | |
1418 | xfs_buftarg_t *btp) | |
1419 | { | |
ce8e922c | 1420 | kmem_free(btp->bt_hash, (1<<btp->bt_hashshift) * sizeof(xfs_bufhash_t)); |
1da177e4 LT |
1421 | btp->bt_hash = NULL; |
1422 | } | |
1423 | ||
a6867a68 | 1424 | /* |
ce8e922c | 1425 | * buftarg list for delwrite queue processing |
a6867a68 DC |
1426 | */ |
1427 | STATIC LIST_HEAD(xfs_buftarg_list); | |
1428 | STATIC DEFINE_SPINLOCK(xfs_buftarg_lock); | |
1429 | ||
1430 | STATIC void | |
1431 | xfs_register_buftarg( | |
1432 | xfs_buftarg_t *btp) | |
1433 | { | |
1434 | spin_lock(&xfs_buftarg_lock); | |
1435 | list_add(&btp->bt_list, &xfs_buftarg_list); | |
1436 | spin_unlock(&xfs_buftarg_lock); | |
1437 | } | |
1438 | ||
1439 | STATIC void | |
1440 | xfs_unregister_buftarg( | |
1441 | xfs_buftarg_t *btp) | |
1442 | { | |
1443 | spin_lock(&xfs_buftarg_lock); | |
1444 | list_del(&btp->bt_list); | |
1445 | spin_unlock(&xfs_buftarg_lock); | |
1446 | } | |
1447 | ||
1da177e4 LT |
1448 | void |
1449 | xfs_free_buftarg( | |
1450 | xfs_buftarg_t *btp, | |
1451 | int external) | |
1452 | { | |
1453 | xfs_flush_buftarg(btp, 1); | |
1454 | if (external) | |
ce8e922c | 1455 | xfs_blkdev_put(btp->bt_bdev); |
1da177e4 | 1456 | xfs_free_bufhash(btp); |
ce8e922c | 1457 | iput(btp->bt_mapping->host); |
a6867a68 | 1458 | |
ce8e922c NS |
1459 | /* Unregister the buftarg first so that we don't get a |
1460 | * wakeup finding a non-existent task | |
1461 | */ | |
a6867a68 DC |
1462 | xfs_unregister_buftarg(btp); |
1463 | kthread_stop(btp->bt_task); | |
1464 | ||
1da177e4 LT |
1465 | kmem_free(btp, sizeof(*btp)); |
1466 | } | |
1467 | ||
1da177e4 LT |
1468 | STATIC int |
1469 | xfs_setsize_buftarg_flags( | |
1470 | xfs_buftarg_t *btp, | |
1471 | unsigned int blocksize, | |
1472 | unsigned int sectorsize, | |
1473 | int verbose) | |
1474 | { | |
ce8e922c NS |
1475 | btp->bt_bsize = blocksize; |
1476 | btp->bt_sshift = ffs(sectorsize) - 1; | |
1477 | btp->bt_smask = sectorsize - 1; | |
1da177e4 | 1478 | |
ce8e922c | 1479 | if (set_blocksize(btp->bt_bdev, sectorsize)) { |
1da177e4 LT |
1480 | printk(KERN_WARNING |
1481 | "XFS: Cannot set_blocksize to %u on device %s\n", | |
1482 | sectorsize, XFS_BUFTARG_NAME(btp)); | |
1483 | return EINVAL; | |
1484 | } | |
1485 | ||
1486 | if (verbose && | |
1487 | (PAGE_CACHE_SIZE / BITS_PER_LONG) > sectorsize) { | |
1488 | printk(KERN_WARNING | |
1489 | "XFS: %u byte sectors in use on device %s. " | |
1490 | "This is suboptimal; %u or greater is ideal.\n", | |
1491 | sectorsize, XFS_BUFTARG_NAME(btp), | |
1492 | (unsigned int)PAGE_CACHE_SIZE / BITS_PER_LONG); | |
1493 | } | |
1494 | ||
1495 | return 0; | |
1496 | } | |
1497 | ||
1498 | /* | |
ce8e922c NS |
1499 | * When allocating the initial buffer target we have not yet |
1500 | * read in the superblock, so don't know what sized sectors | |
1501 | * are being used is at this early stage. Play safe. | |
1502 | */ | |
1da177e4 LT |
1503 | STATIC int |
1504 | xfs_setsize_buftarg_early( | |
1505 | xfs_buftarg_t *btp, | |
1506 | struct block_device *bdev) | |
1507 | { | |
1508 | return xfs_setsize_buftarg_flags(btp, | |
1509 | PAGE_CACHE_SIZE, bdev_hardsect_size(bdev), 0); | |
1510 | } | |
1511 | ||
1512 | int | |
1513 | xfs_setsize_buftarg( | |
1514 | xfs_buftarg_t *btp, | |
1515 | unsigned int blocksize, | |
1516 | unsigned int sectorsize) | |
1517 | { | |
1518 | return xfs_setsize_buftarg_flags(btp, blocksize, sectorsize, 1); | |
1519 | } | |
1520 | ||
1521 | STATIC int | |
1522 | xfs_mapping_buftarg( | |
1523 | xfs_buftarg_t *btp, | |
1524 | struct block_device *bdev) | |
1525 | { | |
1526 | struct backing_dev_info *bdi; | |
1527 | struct inode *inode; | |
1528 | struct address_space *mapping; | |
f5e54d6e | 1529 | static const struct address_space_operations mapping_aops = { |
1da177e4 | 1530 | .sync_page = block_sync_page, |
e965f963 | 1531 | .migratepage = fail_migrate_page, |
1da177e4 LT |
1532 | }; |
1533 | ||
1534 | inode = new_inode(bdev->bd_inode->i_sb); | |
1535 | if (!inode) { | |
1536 | printk(KERN_WARNING | |
1537 | "XFS: Cannot allocate mapping inode for device %s\n", | |
1538 | XFS_BUFTARG_NAME(btp)); | |
1539 | return ENOMEM; | |
1540 | } | |
1541 | inode->i_mode = S_IFBLK; | |
1542 | inode->i_bdev = bdev; | |
1543 | inode->i_rdev = bdev->bd_dev; | |
1544 | bdi = blk_get_backing_dev_info(bdev); | |
1545 | if (!bdi) | |
1546 | bdi = &default_backing_dev_info; | |
1547 | mapping = &inode->i_data; | |
1548 | mapping->a_ops = &mapping_aops; | |
1549 | mapping->backing_dev_info = bdi; | |
1550 | mapping_set_gfp_mask(mapping, GFP_NOFS); | |
ce8e922c | 1551 | btp->bt_mapping = mapping; |
1da177e4 LT |
1552 | return 0; |
1553 | } | |
1554 | ||
a6867a68 DC |
1555 | STATIC int |
1556 | xfs_alloc_delwrite_queue( | |
1557 | xfs_buftarg_t *btp) | |
1558 | { | |
1559 | int error = 0; | |
1560 | ||
1561 | INIT_LIST_HEAD(&btp->bt_list); | |
1562 | INIT_LIST_HEAD(&btp->bt_delwrite_queue); | |
1563 | spinlock_init(&btp->bt_delwrite_lock, "delwri_lock"); | |
1564 | btp->bt_flags = 0; | |
1565 | btp->bt_task = kthread_run(xfsbufd, btp, "xfsbufd"); | |
1566 | if (IS_ERR(btp->bt_task)) { | |
1567 | error = PTR_ERR(btp->bt_task); | |
1568 | goto out_error; | |
1569 | } | |
1570 | xfs_register_buftarg(btp); | |
1571 | out_error: | |
1572 | return error; | |
1573 | } | |
1574 | ||
1da177e4 LT |
1575 | xfs_buftarg_t * |
1576 | xfs_alloc_buftarg( | |
1577 | struct block_device *bdev, | |
1578 | int external) | |
1579 | { | |
1580 | xfs_buftarg_t *btp; | |
1581 | ||
1582 | btp = kmem_zalloc(sizeof(*btp), KM_SLEEP); | |
1583 | ||
ce8e922c NS |
1584 | btp->bt_dev = bdev->bd_dev; |
1585 | btp->bt_bdev = bdev; | |
1da177e4 LT |
1586 | if (xfs_setsize_buftarg_early(btp, bdev)) |
1587 | goto error; | |
1588 | if (xfs_mapping_buftarg(btp, bdev)) | |
1589 | goto error; | |
a6867a68 DC |
1590 | if (xfs_alloc_delwrite_queue(btp)) |
1591 | goto error; | |
1da177e4 LT |
1592 | xfs_alloc_bufhash(btp, external); |
1593 | return btp; | |
1594 | ||
1595 | error: | |
1596 | kmem_free(btp, sizeof(*btp)); | |
1597 | return NULL; | |
1598 | } | |
1599 | ||
1600 | ||
1601 | /* | |
ce8e922c | 1602 | * Delayed write buffer handling |
1da177e4 | 1603 | */ |
1da177e4 | 1604 | STATIC void |
ce8e922c NS |
1605 | xfs_buf_delwri_queue( |
1606 | xfs_buf_t *bp, | |
1da177e4 LT |
1607 | int unlock) |
1608 | { | |
ce8e922c NS |
1609 | struct list_head *dwq = &bp->b_target->bt_delwrite_queue; |
1610 | spinlock_t *dwlk = &bp->b_target->bt_delwrite_lock; | |
a6867a68 | 1611 | |
ce8e922c NS |
1612 | XB_TRACE(bp, "delwri_q", (long)unlock); |
1613 | ASSERT((bp->b_flags&(XBF_DELWRI|XBF_ASYNC)) == (XBF_DELWRI|XBF_ASYNC)); | |
1da177e4 | 1614 | |
a6867a68 | 1615 | spin_lock(dwlk); |
1da177e4 | 1616 | /* If already in the queue, dequeue and place at tail */ |
ce8e922c NS |
1617 | if (!list_empty(&bp->b_list)) { |
1618 | ASSERT(bp->b_flags & _XBF_DELWRI_Q); | |
1619 | if (unlock) | |
1620 | atomic_dec(&bp->b_hold); | |
1621 | list_del(&bp->b_list); | |
1da177e4 LT |
1622 | } |
1623 | ||
ce8e922c NS |
1624 | bp->b_flags |= _XBF_DELWRI_Q; |
1625 | list_add_tail(&bp->b_list, dwq); | |
1626 | bp->b_queuetime = jiffies; | |
a6867a68 | 1627 | spin_unlock(dwlk); |
1da177e4 LT |
1628 | |
1629 | if (unlock) | |
ce8e922c | 1630 | xfs_buf_unlock(bp); |
1da177e4 LT |
1631 | } |
1632 | ||
1633 | void | |
ce8e922c NS |
1634 | xfs_buf_delwri_dequeue( |
1635 | xfs_buf_t *bp) | |
1da177e4 | 1636 | { |
ce8e922c | 1637 | spinlock_t *dwlk = &bp->b_target->bt_delwrite_lock; |
1da177e4 LT |
1638 | int dequeued = 0; |
1639 | ||
a6867a68 | 1640 | spin_lock(dwlk); |
ce8e922c NS |
1641 | if ((bp->b_flags & XBF_DELWRI) && !list_empty(&bp->b_list)) { |
1642 | ASSERT(bp->b_flags & _XBF_DELWRI_Q); | |
1643 | list_del_init(&bp->b_list); | |
1da177e4 LT |
1644 | dequeued = 1; |
1645 | } | |
ce8e922c | 1646 | bp->b_flags &= ~(XBF_DELWRI|_XBF_DELWRI_Q); |
a6867a68 | 1647 | spin_unlock(dwlk); |
1da177e4 LT |
1648 | |
1649 | if (dequeued) | |
ce8e922c | 1650 | xfs_buf_rele(bp); |
1da177e4 | 1651 | |
ce8e922c | 1652 | XB_TRACE(bp, "delwri_dq", (long)dequeued); |
1da177e4 LT |
1653 | } |
1654 | ||
1655 | STATIC void | |
ce8e922c | 1656 | xfs_buf_runall_queues( |
1da177e4 LT |
1657 | struct workqueue_struct *queue) |
1658 | { | |
1659 | flush_workqueue(queue); | |
1660 | } | |
1661 | ||
1da177e4 | 1662 | STATIC int |
23ea4032 | 1663 | xfsbufd_wakeup( |
15c84a47 NS |
1664 | int priority, |
1665 | gfp_t mask) | |
1da177e4 | 1666 | { |
da7f93e9 | 1667 | xfs_buftarg_t *btp; |
a6867a68 DC |
1668 | |
1669 | spin_lock(&xfs_buftarg_lock); | |
da7f93e9 | 1670 | list_for_each_entry(btp, &xfs_buftarg_list, bt_list) { |
ce8e922c | 1671 | if (test_bit(XBT_FORCE_SLEEP, &btp->bt_flags)) |
a6867a68 | 1672 | continue; |
ce8e922c | 1673 | set_bit(XBT_FORCE_FLUSH, &btp->bt_flags); |
a6867a68 DC |
1674 | wake_up_process(btp->bt_task); |
1675 | } | |
1676 | spin_unlock(&xfs_buftarg_lock); | |
1da177e4 LT |
1677 | return 0; |
1678 | } | |
1679 | ||
1680 | STATIC int | |
23ea4032 | 1681 | xfsbufd( |
1da177e4 LT |
1682 | void *data) |
1683 | { | |
1684 | struct list_head tmp; | |
1685 | unsigned long age; | |
a6867a68 | 1686 | xfs_buftarg_t *target = (xfs_buftarg_t *)data; |
ce8e922c | 1687 | xfs_buf_t *bp, *n; |
a6867a68 DC |
1688 | struct list_head *dwq = &target->bt_delwrite_queue; |
1689 | spinlock_t *dwlk = &target->bt_delwrite_lock; | |
f07c2250 | 1690 | int count; |
1da177e4 | 1691 | |
1da177e4 LT |
1692 | current->flags |= PF_MEMALLOC; |
1693 | ||
1da177e4 LT |
1694 | INIT_LIST_HEAD(&tmp); |
1695 | do { | |
3e1d1d28 | 1696 | if (unlikely(freezing(current))) { |
ce8e922c | 1697 | set_bit(XBT_FORCE_SLEEP, &target->bt_flags); |
3e1d1d28 | 1698 | refrigerator(); |
abd0cf7a | 1699 | } else { |
ce8e922c | 1700 | clear_bit(XBT_FORCE_SLEEP, &target->bt_flags); |
abd0cf7a | 1701 | } |
1da177e4 | 1702 | |
15c84a47 NS |
1703 | schedule_timeout_interruptible( |
1704 | xfs_buf_timer_centisecs * msecs_to_jiffies(10)); | |
1da177e4 | 1705 | |
f07c2250 | 1706 | count = 0; |
041e0e3b | 1707 | age = xfs_buf_age_centisecs * msecs_to_jiffies(10); |
a6867a68 | 1708 | spin_lock(dwlk); |
ce8e922c NS |
1709 | list_for_each_entry_safe(bp, n, dwq, b_list) { |
1710 | XB_TRACE(bp, "walkq1", (long)xfs_buf_ispin(bp)); | |
1711 | ASSERT(bp->b_flags & XBF_DELWRI); | |
1da177e4 | 1712 | |
ce8e922c NS |
1713 | if (!xfs_buf_ispin(bp) && !xfs_buf_cond_lock(bp)) { |
1714 | if (!test_bit(XBT_FORCE_FLUSH, | |
a6867a68 | 1715 | &target->bt_flags) && |
1da177e4 | 1716 | time_before(jiffies, |
ce8e922c NS |
1717 | bp->b_queuetime + age)) { |
1718 | xfs_buf_unlock(bp); | |
1da177e4 LT |
1719 | break; |
1720 | } | |
1721 | ||
f07c2250 NS |
1722 | bp->b_flags &= ~(XBF_DELWRI|_XBF_DELWRI_Q| |
1723 | _XBF_RUN_QUEUES); | |
ce8e922c | 1724 | bp->b_flags |= XBF_WRITE; |
f07c2250 NS |
1725 | list_move_tail(&bp->b_list, &tmp); |
1726 | count++; | |
1da177e4 LT |
1727 | } |
1728 | } | |
a6867a68 | 1729 | spin_unlock(dwlk); |
1da177e4 LT |
1730 | |
1731 | while (!list_empty(&tmp)) { | |
ce8e922c NS |
1732 | bp = list_entry(tmp.next, xfs_buf_t, b_list); |
1733 | ASSERT(target == bp->b_target); | |
1da177e4 | 1734 | |
ce8e922c NS |
1735 | list_del_init(&bp->b_list); |
1736 | xfs_buf_iostrategy(bp); | |
1da177e4 LT |
1737 | } |
1738 | ||
1739 | if (as_list_len > 0) | |
1740 | purge_addresses(); | |
f07c2250 NS |
1741 | if (count) |
1742 | blk_run_address_space(target->bt_mapping); | |
1da177e4 | 1743 | |
ce8e922c | 1744 | clear_bit(XBT_FORCE_FLUSH, &target->bt_flags); |
4df08c52 | 1745 | } while (!kthread_should_stop()); |
1da177e4 | 1746 | |
4df08c52 | 1747 | return 0; |
1da177e4 LT |
1748 | } |
1749 | ||
1750 | /* | |
ce8e922c NS |
1751 | * Go through all incore buffers, and release buffers if they belong to |
1752 | * the given device. This is used in filesystem error handling to | |
1753 | * preserve the consistency of its metadata. | |
1da177e4 LT |
1754 | */ |
1755 | int | |
1756 | xfs_flush_buftarg( | |
1757 | xfs_buftarg_t *target, | |
1758 | int wait) | |
1759 | { | |
1760 | struct list_head tmp; | |
ce8e922c | 1761 | xfs_buf_t *bp, *n; |
1da177e4 | 1762 | int pincount = 0; |
a6867a68 DC |
1763 | struct list_head *dwq = &target->bt_delwrite_queue; |
1764 | spinlock_t *dwlk = &target->bt_delwrite_lock; | |
1da177e4 | 1765 | |
ce8e922c NS |
1766 | xfs_buf_runall_queues(xfsdatad_workqueue); |
1767 | xfs_buf_runall_queues(xfslogd_workqueue); | |
1da177e4 LT |
1768 | |
1769 | INIT_LIST_HEAD(&tmp); | |
a6867a68 | 1770 | spin_lock(dwlk); |
ce8e922c NS |
1771 | list_for_each_entry_safe(bp, n, dwq, b_list) { |
1772 | ASSERT(bp->b_target == target); | |
1773 | ASSERT(bp->b_flags & (XBF_DELWRI | _XBF_DELWRI_Q)); | |
1774 | XB_TRACE(bp, "walkq2", (long)xfs_buf_ispin(bp)); | |
1775 | if (xfs_buf_ispin(bp)) { | |
1da177e4 LT |
1776 | pincount++; |
1777 | continue; | |
1778 | } | |
1779 | ||
f07c2250 | 1780 | list_move_tail(&bp->b_list, &tmp); |
1da177e4 | 1781 | } |
a6867a68 | 1782 | spin_unlock(dwlk); |
1da177e4 LT |
1783 | |
1784 | /* | |
1785 | * Dropped the delayed write list lock, now walk the temporary list | |
1786 | */ | |
ce8e922c NS |
1787 | list_for_each_entry_safe(bp, n, &tmp, b_list) { |
1788 | xfs_buf_lock(bp); | |
f07c2250 | 1789 | bp->b_flags &= ~(XBF_DELWRI|_XBF_DELWRI_Q|_XBF_RUN_QUEUES); |
ce8e922c | 1790 | bp->b_flags |= XBF_WRITE; |
1da177e4 | 1791 | if (wait) |
ce8e922c | 1792 | bp->b_flags &= ~XBF_ASYNC; |
1da177e4 | 1793 | else |
ce8e922c | 1794 | list_del_init(&bp->b_list); |
1da177e4 | 1795 | |
ce8e922c | 1796 | xfs_buf_iostrategy(bp); |
1da177e4 LT |
1797 | } |
1798 | ||
f07c2250 NS |
1799 | if (wait) |
1800 | blk_run_address_space(target->bt_mapping); | |
1801 | ||
1da177e4 LT |
1802 | /* |
1803 | * Remaining list items must be flushed before returning | |
1804 | */ | |
1805 | while (!list_empty(&tmp)) { | |
ce8e922c | 1806 | bp = list_entry(tmp.next, xfs_buf_t, b_list); |
1da177e4 | 1807 | |
ce8e922c NS |
1808 | list_del_init(&bp->b_list); |
1809 | xfs_iowait(bp); | |
1810 | xfs_buf_relse(bp); | |
1da177e4 LT |
1811 | } |
1812 | ||
1da177e4 LT |
1813 | return pincount; |
1814 | } | |
1815 | ||
04d8b284 | 1816 | int __init |
ce8e922c | 1817 | xfs_buf_init(void) |
1da177e4 | 1818 | { |
ce8e922c NS |
1819 | #ifdef XFS_BUF_TRACE |
1820 | xfs_buf_trace_buf = ktrace_alloc(XFS_BUF_TRACE_SIZE, KM_SLEEP); | |
04d8b284 CH |
1821 | #endif |
1822 | ||
8758280f NS |
1823 | xfs_buf_zone = kmem_zone_init_flags(sizeof(xfs_buf_t), "xfs_buf", |
1824 | KM_ZONE_HWALIGN, NULL); | |
ce8e922c | 1825 | if (!xfs_buf_zone) |
04d8b284 CH |
1826 | goto out_free_trace_buf; |
1827 | ||
23ea4032 CH |
1828 | xfslogd_workqueue = create_workqueue("xfslogd"); |
1829 | if (!xfslogd_workqueue) | |
04d8b284 | 1830 | goto out_free_buf_zone; |
1da177e4 | 1831 | |
23ea4032 CH |
1832 | xfsdatad_workqueue = create_workqueue("xfsdatad"); |
1833 | if (!xfsdatad_workqueue) | |
1834 | goto out_destroy_xfslogd_workqueue; | |
1da177e4 | 1835 | |
ce8e922c NS |
1836 | xfs_buf_shake = kmem_shake_register(xfsbufd_wakeup); |
1837 | if (!xfs_buf_shake) | |
a6867a68 | 1838 | goto out_destroy_xfsdatad_workqueue; |
04d8b284 | 1839 | |
23ea4032 | 1840 | return 0; |
1da177e4 | 1841 | |
23ea4032 CH |
1842 | out_destroy_xfsdatad_workqueue: |
1843 | destroy_workqueue(xfsdatad_workqueue); | |
1844 | out_destroy_xfslogd_workqueue: | |
1845 | destroy_workqueue(xfslogd_workqueue); | |
23ea4032 | 1846 | out_free_buf_zone: |
ce8e922c | 1847 | kmem_zone_destroy(xfs_buf_zone); |
04d8b284 | 1848 | out_free_trace_buf: |
ce8e922c NS |
1849 | #ifdef XFS_BUF_TRACE |
1850 | ktrace_free(xfs_buf_trace_buf); | |
23ea4032 | 1851 | #endif |
8758280f | 1852 | return -ENOMEM; |
1da177e4 LT |
1853 | } |
1854 | ||
1da177e4 | 1855 | void |
ce8e922c | 1856 | xfs_buf_terminate(void) |
1da177e4 | 1857 | { |
ce8e922c | 1858 | kmem_shake_deregister(xfs_buf_shake); |
04d8b284 CH |
1859 | destroy_workqueue(xfsdatad_workqueue); |
1860 | destroy_workqueue(xfslogd_workqueue); | |
ce8e922c NS |
1861 | kmem_zone_destroy(xfs_buf_zone); |
1862 | #ifdef XFS_BUF_TRACE | |
1863 | ktrace_free(xfs_buf_trace_buf); | |
1da177e4 | 1864 | #endif |
1da177e4 | 1865 | } |