hyperv: Add processing of MTU reduced by the host
[linux/fpc-iii.git] / fs / xfs / xfs_extfree_item.c
blobc4327419dc5cbc5f3b0e33f00ae6a01afd24e300
1 /*
2 * Copyright (c) 2000-2001,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
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.
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.
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
18 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_log_format.h"
21 #include "xfs_trans_resv.h"
22 #include "xfs_sb.h"
23 #include "xfs_ag.h"
24 #include "xfs_mount.h"
25 #include "xfs_trans.h"
26 #include "xfs_trans_priv.h"
27 #include "xfs_buf_item.h"
28 #include "xfs_extfree_item.h"
29 #include "xfs_log.h"
32 kmem_zone_t *xfs_efi_zone;
33 kmem_zone_t *xfs_efd_zone;
35 static inline struct xfs_efi_log_item *EFI_ITEM(struct xfs_log_item *lip)
37 return container_of(lip, struct xfs_efi_log_item, efi_item);
40 void
41 xfs_efi_item_free(
42 struct xfs_efi_log_item *efip)
44 if (efip->efi_format.efi_nextents > XFS_EFI_MAX_FAST_EXTENTS)
45 kmem_free(efip);
46 else
47 kmem_zone_free(xfs_efi_zone, efip);
51 * Freeing the efi requires that we remove it from the AIL if it has already
52 * been placed there. However, the EFI may not yet have been placed in the AIL
53 * when called by xfs_efi_release() from EFD processing due to the ordering of
54 * committed vs unpin operations in bulk insert operations. Hence the reference
55 * count to ensure only the last caller frees the EFI.
57 STATIC void
58 __xfs_efi_release(
59 struct xfs_efi_log_item *efip)
61 struct xfs_ail *ailp = efip->efi_item.li_ailp;
63 if (atomic_dec_and_test(&efip->efi_refcount)) {
64 spin_lock(&ailp->xa_lock);
65 /* xfs_trans_ail_delete() drops the AIL lock. */
66 xfs_trans_ail_delete(ailp, &efip->efi_item,
67 SHUTDOWN_LOG_IO_ERROR);
68 xfs_efi_item_free(efip);
73 * This returns the number of iovecs needed to log the given efi item.
74 * We only need 1 iovec for an efi item. It just logs the efi_log_format
75 * structure.
77 static inline int
78 xfs_efi_item_sizeof(
79 struct xfs_efi_log_item *efip)
81 return sizeof(struct xfs_efi_log_format) +
82 (efip->efi_format.efi_nextents - 1) * sizeof(xfs_extent_t);
85 STATIC void
86 xfs_efi_item_size(
87 struct xfs_log_item *lip,
88 int *nvecs,
89 int *nbytes)
91 *nvecs += 1;
92 *nbytes += xfs_efi_item_sizeof(EFI_ITEM(lip));
96 * This is called to fill in the vector of log iovecs for the
97 * given efi log item. We use only 1 iovec, and we point that
98 * at the efi_log_format structure embedded in the efi item.
99 * It is at this point that we assert that all of the extent
100 * slots in the efi item have been filled.
102 STATIC void
103 xfs_efi_item_format(
104 struct xfs_log_item *lip,
105 struct xfs_log_vec *lv)
107 struct xfs_efi_log_item *efip = EFI_ITEM(lip);
108 struct xfs_log_iovec *vecp = NULL;
110 ASSERT(atomic_read(&efip->efi_next_extent) ==
111 efip->efi_format.efi_nextents);
113 efip->efi_format.efi_type = XFS_LI_EFI;
114 efip->efi_format.efi_size = 1;
116 xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_EFI_FORMAT,
117 &efip->efi_format,
118 xfs_efi_item_sizeof(efip));
123 * Pinning has no meaning for an efi item, so just return.
125 STATIC void
126 xfs_efi_item_pin(
127 struct xfs_log_item *lip)
132 * While EFIs cannot really be pinned, the unpin operation is the last place at
133 * which the EFI is manipulated during a transaction. If we are being asked to
134 * remove the EFI it's because the transaction has been cancelled and by
135 * definition that means the EFI cannot be in the AIL so remove it from the
136 * transaction and free it. Otherwise coordinate with xfs_efi_release()
137 * to determine who gets to free the EFI.
139 STATIC void
140 xfs_efi_item_unpin(
141 struct xfs_log_item *lip,
142 int remove)
144 struct xfs_efi_log_item *efip = EFI_ITEM(lip);
146 if (remove) {
147 ASSERT(!(lip->li_flags & XFS_LI_IN_AIL));
148 if (lip->li_desc)
149 xfs_trans_del_item(lip);
150 xfs_efi_item_free(efip);
151 return;
153 __xfs_efi_release(efip);
157 * Efi items have no locking or pushing. However, since EFIs are pulled from
158 * the AIL when their corresponding EFDs are committed to disk, their situation
159 * is very similar to being pinned. Return XFS_ITEM_PINNED so that the caller
160 * will eventually flush the log. This should help in getting the EFI out of
161 * the AIL.
163 STATIC uint
164 xfs_efi_item_push(
165 struct xfs_log_item *lip,
166 struct list_head *buffer_list)
168 return XFS_ITEM_PINNED;
171 STATIC void
172 xfs_efi_item_unlock(
173 struct xfs_log_item *lip)
175 if (lip->li_flags & XFS_LI_ABORTED)
176 xfs_efi_item_free(EFI_ITEM(lip));
180 * The EFI is logged only once and cannot be moved in the log, so simply return
181 * the lsn at which it's been logged.
183 STATIC xfs_lsn_t
184 xfs_efi_item_committed(
185 struct xfs_log_item *lip,
186 xfs_lsn_t lsn)
188 return lsn;
192 * The EFI dependency tracking op doesn't do squat. It can't because
193 * it doesn't know where the free extent is coming from. The dependency
194 * tracking has to be handled by the "enclosing" metadata object. For
195 * example, for inodes, the inode is locked throughout the extent freeing
196 * so the dependency should be recorded there.
198 STATIC void
199 xfs_efi_item_committing(
200 struct xfs_log_item *lip,
201 xfs_lsn_t lsn)
206 * This is the ops vector shared by all efi log items.
208 static const struct xfs_item_ops xfs_efi_item_ops = {
209 .iop_size = xfs_efi_item_size,
210 .iop_format = xfs_efi_item_format,
211 .iop_pin = xfs_efi_item_pin,
212 .iop_unpin = xfs_efi_item_unpin,
213 .iop_unlock = xfs_efi_item_unlock,
214 .iop_committed = xfs_efi_item_committed,
215 .iop_push = xfs_efi_item_push,
216 .iop_committing = xfs_efi_item_committing
221 * Allocate and initialize an efi item with the given number of extents.
223 struct xfs_efi_log_item *
224 xfs_efi_init(
225 struct xfs_mount *mp,
226 uint nextents)
229 struct xfs_efi_log_item *efip;
230 uint size;
232 ASSERT(nextents > 0);
233 if (nextents > XFS_EFI_MAX_FAST_EXTENTS) {
234 size = (uint)(sizeof(xfs_efi_log_item_t) +
235 ((nextents - 1) * sizeof(xfs_extent_t)));
236 efip = kmem_zalloc(size, KM_SLEEP);
237 } else {
238 efip = kmem_zone_zalloc(xfs_efi_zone, KM_SLEEP);
241 xfs_log_item_init(mp, &efip->efi_item, XFS_LI_EFI, &xfs_efi_item_ops);
242 efip->efi_format.efi_nextents = nextents;
243 efip->efi_format.efi_id = (__psint_t)(void*)efip;
244 atomic_set(&efip->efi_next_extent, 0);
245 atomic_set(&efip->efi_refcount, 2);
247 return efip;
251 * Copy an EFI format buffer from the given buf, and into the destination
252 * EFI format structure.
253 * The given buffer can be in 32 bit or 64 bit form (which has different padding),
254 * one of which will be the native format for this kernel.
255 * It will handle the conversion of formats if necessary.
258 xfs_efi_copy_format(xfs_log_iovec_t *buf, xfs_efi_log_format_t *dst_efi_fmt)
260 xfs_efi_log_format_t *src_efi_fmt = buf->i_addr;
261 uint i;
262 uint len = sizeof(xfs_efi_log_format_t) +
263 (src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_t);
264 uint len32 = sizeof(xfs_efi_log_format_32_t) +
265 (src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_32_t);
266 uint len64 = sizeof(xfs_efi_log_format_64_t) +
267 (src_efi_fmt->efi_nextents - 1) * sizeof(xfs_extent_64_t);
269 if (buf->i_len == len) {
270 memcpy((char *)dst_efi_fmt, (char*)src_efi_fmt, len);
271 return 0;
272 } else if (buf->i_len == len32) {
273 xfs_efi_log_format_32_t *src_efi_fmt_32 = buf->i_addr;
275 dst_efi_fmt->efi_type = src_efi_fmt_32->efi_type;
276 dst_efi_fmt->efi_size = src_efi_fmt_32->efi_size;
277 dst_efi_fmt->efi_nextents = src_efi_fmt_32->efi_nextents;
278 dst_efi_fmt->efi_id = src_efi_fmt_32->efi_id;
279 for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
280 dst_efi_fmt->efi_extents[i].ext_start =
281 src_efi_fmt_32->efi_extents[i].ext_start;
282 dst_efi_fmt->efi_extents[i].ext_len =
283 src_efi_fmt_32->efi_extents[i].ext_len;
285 return 0;
286 } else if (buf->i_len == len64) {
287 xfs_efi_log_format_64_t *src_efi_fmt_64 = buf->i_addr;
289 dst_efi_fmt->efi_type = src_efi_fmt_64->efi_type;
290 dst_efi_fmt->efi_size = src_efi_fmt_64->efi_size;
291 dst_efi_fmt->efi_nextents = src_efi_fmt_64->efi_nextents;
292 dst_efi_fmt->efi_id = src_efi_fmt_64->efi_id;
293 for (i = 0; i < dst_efi_fmt->efi_nextents; i++) {
294 dst_efi_fmt->efi_extents[i].ext_start =
295 src_efi_fmt_64->efi_extents[i].ext_start;
296 dst_efi_fmt->efi_extents[i].ext_len =
297 src_efi_fmt_64->efi_extents[i].ext_len;
299 return 0;
301 return -EFSCORRUPTED;
305 * This is called by the efd item code below to release references to the given
306 * efi item. Each efd calls this with the number of extents that it has
307 * logged, and when the sum of these reaches the total number of extents logged
308 * by this efi item we can free the efi item.
310 void
311 xfs_efi_release(xfs_efi_log_item_t *efip,
312 uint nextents)
314 ASSERT(atomic_read(&efip->efi_next_extent) >= nextents);
315 if (atomic_sub_and_test(nextents, &efip->efi_next_extent)) {
316 /* recovery needs us to drop the EFI reference, too */
317 if (test_bit(XFS_EFI_RECOVERED, &efip->efi_flags))
318 __xfs_efi_release(efip);
320 __xfs_efi_release(efip);
321 /* efip may now have been freed, do not reference it again. */
325 static inline struct xfs_efd_log_item *EFD_ITEM(struct xfs_log_item *lip)
327 return container_of(lip, struct xfs_efd_log_item, efd_item);
330 STATIC void
331 xfs_efd_item_free(struct xfs_efd_log_item *efdp)
333 if (efdp->efd_format.efd_nextents > XFS_EFD_MAX_FAST_EXTENTS)
334 kmem_free(efdp);
335 else
336 kmem_zone_free(xfs_efd_zone, efdp);
340 * This returns the number of iovecs needed to log the given efd item.
341 * We only need 1 iovec for an efd item. It just logs the efd_log_format
342 * structure.
344 static inline int
345 xfs_efd_item_sizeof(
346 struct xfs_efd_log_item *efdp)
348 return sizeof(xfs_efd_log_format_t) +
349 (efdp->efd_format.efd_nextents - 1) * sizeof(xfs_extent_t);
352 STATIC void
353 xfs_efd_item_size(
354 struct xfs_log_item *lip,
355 int *nvecs,
356 int *nbytes)
358 *nvecs += 1;
359 *nbytes += xfs_efd_item_sizeof(EFD_ITEM(lip));
363 * This is called to fill in the vector of log iovecs for the
364 * given efd log item. We use only 1 iovec, and we point that
365 * at the efd_log_format structure embedded in the efd item.
366 * It is at this point that we assert that all of the extent
367 * slots in the efd item have been filled.
369 STATIC void
370 xfs_efd_item_format(
371 struct xfs_log_item *lip,
372 struct xfs_log_vec *lv)
374 struct xfs_efd_log_item *efdp = EFD_ITEM(lip);
375 struct xfs_log_iovec *vecp = NULL;
377 ASSERT(efdp->efd_next_extent == efdp->efd_format.efd_nextents);
379 efdp->efd_format.efd_type = XFS_LI_EFD;
380 efdp->efd_format.efd_size = 1;
382 xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_EFD_FORMAT,
383 &efdp->efd_format,
384 xfs_efd_item_sizeof(efdp));
388 * Pinning has no meaning for an efd item, so just return.
390 STATIC void
391 xfs_efd_item_pin(
392 struct xfs_log_item *lip)
397 * Since pinning has no meaning for an efd item, unpinning does
398 * not either.
400 STATIC void
401 xfs_efd_item_unpin(
402 struct xfs_log_item *lip,
403 int remove)
408 * There isn't much you can do to push on an efd item. It is simply stuck
409 * waiting for the log to be flushed to disk.
411 STATIC uint
412 xfs_efd_item_push(
413 struct xfs_log_item *lip,
414 struct list_head *buffer_list)
416 return XFS_ITEM_PINNED;
419 STATIC void
420 xfs_efd_item_unlock(
421 struct xfs_log_item *lip)
423 if (lip->li_flags & XFS_LI_ABORTED)
424 xfs_efd_item_free(EFD_ITEM(lip));
428 * When the efd item is committed to disk, all we need to do
429 * is delete our reference to our partner efi item and then
430 * free ourselves. Since we're freeing ourselves we must
431 * return -1 to keep the transaction code from further referencing
432 * this item.
434 STATIC xfs_lsn_t
435 xfs_efd_item_committed(
436 struct xfs_log_item *lip,
437 xfs_lsn_t lsn)
439 struct xfs_efd_log_item *efdp = EFD_ITEM(lip);
442 * If we got a log I/O error, it's always the case that the LR with the
443 * EFI got unpinned and freed before the EFD got aborted.
445 if (!(lip->li_flags & XFS_LI_ABORTED))
446 xfs_efi_release(efdp->efd_efip, efdp->efd_format.efd_nextents);
448 xfs_efd_item_free(efdp);
449 return (xfs_lsn_t)-1;
453 * The EFD dependency tracking op doesn't do squat. It can't because
454 * it doesn't know where the free extent is coming from. The dependency
455 * tracking has to be handled by the "enclosing" metadata object. For
456 * example, for inodes, the inode is locked throughout the extent freeing
457 * so the dependency should be recorded there.
459 STATIC void
460 xfs_efd_item_committing(
461 struct xfs_log_item *lip,
462 xfs_lsn_t lsn)
467 * This is the ops vector shared by all efd log items.
469 static const struct xfs_item_ops xfs_efd_item_ops = {
470 .iop_size = xfs_efd_item_size,
471 .iop_format = xfs_efd_item_format,
472 .iop_pin = xfs_efd_item_pin,
473 .iop_unpin = xfs_efd_item_unpin,
474 .iop_unlock = xfs_efd_item_unlock,
475 .iop_committed = xfs_efd_item_committed,
476 .iop_push = xfs_efd_item_push,
477 .iop_committing = xfs_efd_item_committing
481 * Allocate and initialize an efd item with the given number of extents.
483 struct xfs_efd_log_item *
484 xfs_efd_init(
485 struct xfs_mount *mp,
486 struct xfs_efi_log_item *efip,
487 uint nextents)
490 struct xfs_efd_log_item *efdp;
491 uint size;
493 ASSERT(nextents > 0);
494 if (nextents > XFS_EFD_MAX_FAST_EXTENTS) {
495 size = (uint)(sizeof(xfs_efd_log_item_t) +
496 ((nextents - 1) * sizeof(xfs_extent_t)));
497 efdp = kmem_zalloc(size, KM_SLEEP);
498 } else {
499 efdp = kmem_zone_zalloc(xfs_efd_zone, KM_SLEEP);
502 xfs_log_item_init(mp, &efdp->efd_item, XFS_LI_EFD, &xfs_efd_item_ops);
503 efdp->efd_efip = efip;
504 efdp->efd_format.efd_nextents = nextents;
505 efdp->efd_format.efd_efi_id = efip->efi_format.efi_id;
507 return efdp;