Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / xfs / xfs_extfree_item.c
1 /*
2 * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
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
7 * published by the Free Software Foundation.
8 *
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.
13 *
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
17 */
18 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_types.h"
21 #include "xfs_log.h"
22 #include "xfs_trans.h"
23 #include "xfs_buf_item.h"
24 #include "xfs_sb.h"
25 #include "xfs_ag.h"
26 #include "xfs_mount.h"
27 #include "xfs_trans_priv.h"
28 #include "xfs_extfree_item.h"
29
30
31 kmem_zone_t *xfs_efi_zone;
32 kmem_zone_t *xfs_efd_zone;
33
34 static inline struct xfs_efi_log_item *EFI_ITEM(struct xfs_log_item *lip)
35 {
36 return container_of(lip, struct xfs_efi_log_item, efi_item);
37 }
38
39 void
40 xfs_efi_item_free(
41 struct xfs_efi_log_item *efip)
42 {
43 if (efip->efi_format.efi_nextents > XFS_EFI_MAX_FAST_EXTENTS)
44 kmem_free(efip);
45 else
46 kmem_zone_free(xfs_efi_zone, efip);
47 }
48
49 /*
50 * Freeing the efi requires that we remove it from the AIL if it has already
51 * been placed there. However, the EFI may not yet have been placed in the AIL
52 * when called by xfs_efi_release() from EFD processing due to the ordering of
53 * committed vs unpin operations in bulk insert operations. Hence the reference
54 * count to ensure only the last caller frees the EFI.
55 */
56 STATIC void
57 __xfs_efi_release(
58 struct xfs_efi_log_item *efip)
59 {
60 struct xfs_ail *ailp = efip->efi_item.li_ailp;
61
62 if (atomic_dec_and_test(&efip->efi_refcount)) {
63 spin_lock(&ailp->xa_lock);
64 /* xfs_trans_ail_delete() drops the AIL lock. */
65 xfs_trans_ail_delete(ailp, &efip->efi_item,
66 SHUTDOWN_LOG_IO_ERROR);
67 xfs_efi_item_free(efip);
68 }
69 }
70
71 /*
72 * This returns the number of iovecs needed to log the given efi item.
73 * We only need 1 iovec for an efi item. It just logs the efi_log_format
74 * structure.
75 */
76 STATIC uint
77 xfs_efi_item_size(
78 struct xfs_log_item *lip)
79 {
80 return 1;
81 }
82
83 /*
84 * This is called to fill in the vector of log iovecs for the
85 * given efi log item. We use only 1 iovec, and we point that
86 * at the efi_log_format structure embedded in the efi item.
87 * It is at this point that we assert that all of the extent
88 * slots in the efi item have been filled.
89 */
90 STATIC void
91 xfs_efi_item_format(
92 struct xfs_log_item *lip,
93 struct xfs_log_iovec *log_vector)
94 {
95 struct xfs_efi_log_item *efip = EFI_ITEM(lip);
96 uint size;
97
98 ASSERT(atomic_read(&efip->efi_next_extent) ==
99 efip->efi_format.efi_nextents);
100
101 efip->efi_format.efi_type = XFS_LI_EFI;
102
103 size = sizeof(xfs_efi_log_format_t);
104 size += (efip->efi_format.efi_nextents - 1) * sizeof(xfs_extent_t);
105 efip->efi_format.efi_size = 1;
106
107 log_vector->i_addr = &efip->efi_format;
108 log_vector->i_len = size;
109 log_vector->i_type = XLOG_REG_TYPE_EFI_FORMAT;
110 ASSERT(size >= sizeof(xfs_efi_log_format_t));
111 }
112
113
114 /*
115 * Pinning has no meaning for an efi item, so just return.
116 */
117 STATIC void
118 xfs_efi_item_pin(
119 struct xfs_log_item *lip)
120 {
121 }
122
123 /*
124 * While EFIs cannot really be pinned, the unpin operation is the last place at
125 * which the EFI is manipulated during a transaction. If we are being asked to
126 * remove the EFI it's because the transaction has been cancelled and by
127 * definition that means the EFI cannot be in the AIL so remove it from the
128 * transaction and free it. Otherwise coordinate with xfs_efi_release()
129 * to determine who gets to free the EFI.
130 */
131 STATIC void
132 xfs_efi_item_unpin(
133 struct xfs_log_item *lip,
134 int remove)
135 {
136 struct xfs_efi_log_item *efip = EFI_ITEM(lip);
137
138 if (remove) {
139 ASSERT(!(lip->li_flags & XFS_LI_IN_AIL));
140 if (lip->li_desc)
141 xfs_trans_del_item(lip);
142 xfs_efi_item_free(efip);
143 return;
144 }
145 __xfs_efi_release(efip);
146 }
147
148 /*
149 * Efi items have no locking or pushing. However, since EFIs are pulled from
150 * the AIL when their corresponding EFDs are committed to disk, their situation
151 * is very similar to being pinned. Return XFS_ITEM_PINNED so that the caller
152 * will eventually flush the log. This should help in getting the EFI out of
153 * the AIL.
154 */
155 STATIC uint
156 xfs_efi_item_push(
157 struct xfs_log_item *lip,
158 struct list_head *buffer_list)
159 {
160 return XFS_ITEM_PINNED;
161 }
162
163 STATIC void
164 xfs_efi_item_unlock(
165 struct xfs_log_item *lip)
166 {
167 if (lip->li_flags & XFS_LI_ABORTED)
168 xfs_efi_item_free(EFI_ITEM(lip));
169 }
170
171 /*
172 * The EFI is logged only once and cannot be moved in the log, so simply return
173 * the lsn at which it's been logged.
174 */
175 STATIC xfs_lsn_t
176 xfs_efi_item_committed(
177 struct xfs_log_item *lip,
178 xfs_lsn_t lsn)
179 {
180 return lsn;
181 }
182
183 /*
184 * The EFI dependency tracking op doesn't do squat. It can't because
185 * it doesn't know where the free extent is coming from. The dependency
186 * tracking has to be handled by the "enclosing" metadata object. For
187 * example, for inodes, the inode is locked throughout the extent freeing
188 * so the dependency should be recorded there.
189 */
190 STATIC void
191 xfs_efi_item_committing(
192 struct xfs_log_item *lip,
193 xfs_lsn_t lsn)
194 {
195 }
196
197 /*
198 * This is the ops vector shared by all efi log items.
199 */
200 static const struct xfs_item_ops xfs_efi_item_ops = {
201 .iop_size = xfs_efi_item_size,
202 .iop_format = xfs_efi_item_format,
203 .iop_pin = xfs_efi_item_pin,
204 .iop_unpin = xfs_efi_item_unpin,
205 .iop_unlock = xfs_efi_item_unlock,
206 .iop_committed = xfs_efi_item_committed,
207 .iop_push = xfs_efi_item_push,
208 .iop_committing = xfs_efi_item_committing
209 };
210
211
212 /*
213 * Allocate and initialize an efi item with the given number of extents.
214 */
215 struct xfs_efi_log_item *
216 xfs_efi_init(
217 struct xfs_mount *mp,
218 uint nextents)
219
220 {
221 struct xfs_efi_log_item *efip;
222 uint size;
223
224 ASSERT(nextents > 0);
225 if (nextents > XFS_EFI_MAX_FAST_EXTENTS) {
226 size = (uint)(sizeof(xfs_efi_log_item_t) +
227 ((nextents - 1) * sizeof(xfs_extent_t)));
228 efip = kmem_zalloc(size, KM_SLEEP);
229 } else {
230 efip = kmem_zone_zalloc(xfs_efi_zone, KM_SLEEP);
231 }
232
233 xfs_log_item_init(mp, &efip->efi_item, XFS_LI_EFI, &xfs_efi_item_ops);
234 efip->efi_format.efi_nextents = nextents;
235 efip->efi_format.efi_id = (__psint_t)(void*)efip;
236 atomic_set(&efip->efi_next_extent, 0);
237 atomic_set(&efip->efi_refcount, 2);
238
239 return efip;
240 }
241
242 /*
243 * Copy an EFI format buffer from the given buf, and into the destination
244 * EFI format structure.
245 * The given buffer can be in 32 bit or 64 bit form (which has different padding),
246 * one of which will be the native format for this kernel.
247 * It will handle the conversion of formats if necessary.
248 */
249 int
250 xfs_efi_copy_format(xfs_log_iovec_t *buf, xfs_efi_log_format_t *dst_efi_fmt)
251 {
252 xfs_efi_log_format_t *src_efi_fmt = buf->i_addr;
253 uint i;
254 uint len = sizeof(xfs_efi_log_format_t) +
255 (src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_t);
256 uint len32 = sizeof(xfs_efi_log_format_32_t) +
257 (src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_32_t);
258 uint len64 = sizeof(xfs_efi_log_format_64_t) +
259 (src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_64_t);
260
261 if (buf->i_len == len) {
262 memcpy((char *)dst_efi_fmt, (char*)src_efi_fmt, len);
263 return 0;
264 } else if (buf->i_len == len32) {
265 xfs_efi_log_format_32_t *src_efi_fmt_32 = buf->i_addr;
266
267 dst_efi_fmt->efi_type = src_efi_fmt_32->efi_type;
268 dst_efi_fmt->efi_size = src_efi_fmt_32->efi_size;
269 dst_efi_fmt->efi_nextents = src_efi_fmt_32->efi_nextents;
270 dst_efi_fmt->efi_id = src_efi_fmt_32->efi_id;
271 for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
272 dst_efi_fmt->efi_extents[i].ext_start =
273 src_efi_fmt_32->efi_extents[i].ext_start;
274 dst_efi_fmt->efi_extents[i].ext_len =
275 src_efi_fmt_32->efi_extents[i].ext_len;
276 }
277 return 0;
278 } else if (buf->i_len == len64) {
279 xfs_efi_log_format_64_t *src_efi_fmt_64 = buf->i_addr;
280
281 dst_efi_fmt->efi_type = src_efi_fmt_64->efi_type;
282 dst_efi_fmt->efi_size = src_efi_fmt_64->efi_size;
283 dst_efi_fmt->efi_nextents = src_efi_fmt_64->efi_nextents;
284 dst_efi_fmt->efi_id = src_efi_fmt_64->efi_id;
285 for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
286 dst_efi_fmt->efi_extents[i].ext_start =
287 src_efi_fmt_64->efi_extents[i].ext_start;
288 dst_efi_fmt->efi_extents[i].ext_len =
289 src_efi_fmt_64->efi_extents[i].ext_len;
290 }
291 return 0;
292 }
293 return EFSCORRUPTED;
294 }
295
296 /*
297 * This is called by the efd item code below to release references to the given
298 * efi item. Each efd calls this with the number of extents that it has
299 * logged, and when the sum of these reaches the total number of extents logged
300 * by this efi item we can free the efi item.
301 */
302 void
303 xfs_efi_release(xfs_efi_log_item_t *efip,
304 uint nextents)
305 {
306 ASSERT(atomic_read(&efip->efi_next_extent) >= nextents);
307 if (atomic_sub_and_test(nextents, &efip->efi_next_extent)) {
308 /* recovery needs us to drop the EFI reference, too */
309 if (test_bit(XFS_EFI_RECOVERED, &efip->efi_flags))
310 __xfs_efi_release(efip);
311
312 __xfs_efi_release(efip);
313 /* efip may now have been freed, do not reference it again. */
314 }
315 }
316
317 static inline struct xfs_efd_log_item *EFD_ITEM(struct xfs_log_item *lip)
318 {
319 return container_of(lip, struct xfs_efd_log_item, efd_item);
320 }
321
322 STATIC void
323 xfs_efd_item_free(struct xfs_efd_log_item *efdp)
324 {
325 if (efdp->efd_format.efd_nextents > XFS_EFD_MAX_FAST_EXTENTS)
326 kmem_free(efdp);
327 else
328 kmem_zone_free(xfs_efd_zone, efdp);
329 }
330
331 /*
332 * This returns the number of iovecs needed to log the given efd item.
333 * We only need 1 iovec for an efd item. It just logs the efd_log_format
334 * structure.
335 */
336 STATIC uint
337 xfs_efd_item_size(
338 struct xfs_log_item *lip)
339 {
340 return 1;
341 }
342
343 /*
344 * This is called to fill in the vector of log iovecs for the
345 * given efd log item. We use only 1 iovec, and we point that
346 * at the efd_log_format structure embedded in the efd item.
347 * It is at this point that we assert that all of the extent
348 * slots in the efd item have been filled.
349 */
350 STATIC void
351 xfs_efd_item_format(
352 struct xfs_log_item *lip,
353 struct xfs_log_iovec *log_vector)
354 {
355 struct xfs_efd_log_item *efdp = EFD_ITEM(lip);
356 uint size;
357
358 ASSERT(efdp->efd_next_extent == efdp->efd_format.efd_nextents);
359
360 efdp->efd_format.efd_type = XFS_LI_EFD;
361
362 size = sizeof(xfs_efd_log_format_t);
363 size += (efdp->efd_format.efd_nextents - 1) * sizeof(xfs_extent_t);
364 efdp->efd_format.efd_size = 1;
365
366 log_vector->i_addr = &efdp->efd_format;
367 log_vector->i_len = size;
368 log_vector->i_type = XLOG_REG_TYPE_EFD_FORMAT;
369 ASSERT(size >= sizeof(xfs_efd_log_format_t));
370 }
371
372 /*
373 * Pinning has no meaning for an efd item, so just return.
374 */
375 STATIC void
376 xfs_efd_item_pin(
377 struct xfs_log_item *lip)
378 {
379 }
380
381 /*
382 * Since pinning has no meaning for an efd item, unpinning does
383 * not either.
384 */
385 STATIC void
386 xfs_efd_item_unpin(
387 struct xfs_log_item *lip,
388 int remove)
389 {
390 }
391
392 /*
393 * There isn't much you can do to push on an efd item. It is simply stuck
394 * waiting for the log to be flushed to disk.
395 */
396 STATIC uint
397 xfs_efd_item_push(
398 struct xfs_log_item *lip,
399 struct list_head *buffer_list)
400 {
401 return XFS_ITEM_PINNED;
402 }
403
404 STATIC void
405 xfs_efd_item_unlock(
406 struct xfs_log_item *lip)
407 {
408 if (lip->li_flags & XFS_LI_ABORTED)
409 xfs_efd_item_free(EFD_ITEM(lip));
410 }
411
412 /*
413 * When the efd item is committed to disk, all we need to do
414 * is delete our reference to our partner efi item and then
415 * free ourselves. Since we're freeing ourselves we must
416 * return -1 to keep the transaction code from further referencing
417 * this item.
418 */
419 STATIC xfs_lsn_t
420 xfs_efd_item_committed(
421 struct xfs_log_item *lip,
422 xfs_lsn_t lsn)
423 {
424 struct xfs_efd_log_item *efdp = EFD_ITEM(lip);
425
426 /*
427 * If we got a log I/O error, it's always the case that the LR with the
428 * EFI got unpinned and freed before the EFD got aborted.
429 */
430 if (!(lip->li_flags & XFS_LI_ABORTED))
431 xfs_efi_release(efdp->efd_efip, efdp->efd_format.efd_nextents);
432
433 xfs_efd_item_free(efdp);
434 return (xfs_lsn_t)-1;
435 }
436
437 /*
438 * The EFD dependency tracking op doesn't do squat. It can't because
439 * it doesn't know where the free extent is coming from. The dependency
440 * tracking has to be handled by the "enclosing" metadata object. For
441 * example, for inodes, the inode is locked throughout the extent freeing
442 * so the dependency should be recorded there.
443 */
444 STATIC void
445 xfs_efd_item_committing(
446 struct xfs_log_item *lip,
447 xfs_lsn_t lsn)
448 {
449 }
450
451 /*
452 * This is the ops vector shared by all efd log items.
453 */
454 static const struct xfs_item_ops xfs_efd_item_ops = {
455 .iop_size = xfs_efd_item_size,
456 .iop_format = xfs_efd_item_format,
457 .iop_pin = xfs_efd_item_pin,
458 .iop_unpin = xfs_efd_item_unpin,
459 .iop_unlock = xfs_efd_item_unlock,
460 .iop_committed = xfs_efd_item_committed,
461 .iop_push = xfs_efd_item_push,
462 .iop_committing = xfs_efd_item_committing
463 };
464
465 /*
466 * Allocate and initialize an efd item with the given number of extents.
467 */
468 struct xfs_efd_log_item *
469 xfs_efd_init(
470 struct xfs_mount *mp,
471 struct xfs_efi_log_item *efip,
472 uint nextents)
473
474 {
475 struct xfs_efd_log_item *efdp;
476 uint size;
477
478 ASSERT(nextents > 0);
479 if (nextents > XFS_EFD_MAX_FAST_EXTENTS) {
480 size = (uint)(sizeof(xfs_efd_log_item_t) +
481 ((nextents - 1) * sizeof(xfs_extent_t)));
482 efdp = kmem_zalloc(size, KM_SLEEP);
483 } else {
484 efdp = kmem_zone_zalloc(xfs_efd_zone, KM_SLEEP);
485 }
486
487 xfs_log_item_init(mp, &efdp->efd_item, XFS_LI_EFD, &xfs_efd_item_ops);
488 efdp->efd_efip = efip;
489 efdp->efd_format.efd_nextents = nextents;
490 efdp->efd_format.efd_efi_id = efip->efi_format.efi_id;
491
492 return efdp;
493 }