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[linux-2.6/libata-dev.git] / fs / gfs2 / glops.c
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1 /*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
5 * This copyrighted material is made available to anyone wishing to use,
6 * modify, copy, or redistribute it subject to the terms and conditions
7 * of the GNU General Public License version 2.
8 */
10 #include <linux/spinlock.h>
11 #include <linux/completion.h>
12 #include <linux/buffer_head.h>
13 #include <linux/gfs2_ondisk.h>
14 #include <linux/bio.h>
15 #include <linux/posix_acl.h>
17 #include "gfs2.h"
18 #include "incore.h"
19 #include "bmap.h"
20 #include "glock.h"
21 #include "glops.h"
22 #include "inode.h"
23 #include "log.h"
24 #include "meta_io.h"
25 #include "recovery.h"
26 #include "rgrp.h"
27 #include "util.h"
28 #include "trans.h"
30 /**
31 * __gfs2_ail_flush - remove all buffers for a given lock from the AIL
32 * @gl: the glock
34 * None of the buffers should be dirty, locked, or pinned.
37 static void __gfs2_ail_flush(struct gfs2_glock *gl)
39 struct gfs2_sbd *sdp = gl->gl_sbd;
40 struct list_head *head = &gl->gl_ail_list;
41 struct gfs2_bufdata *bd;
42 struct buffer_head *bh;
44 spin_lock(&sdp->sd_ail_lock);
45 while (!list_empty(head)) {
46 bd = list_entry(head->next, struct gfs2_bufdata,
47 bd_ail_gl_list);
48 bh = bd->bd_bh;
49 gfs2_remove_from_ail(bd);
50 spin_unlock(&sdp->sd_ail_lock);
52 bd->bd_bh = NULL;
53 bh->b_private = NULL;
54 bd->bd_blkno = bh->b_blocknr;
55 gfs2_log_lock(sdp);
56 gfs2_assert_withdraw(sdp, !buffer_busy(bh));
57 gfs2_trans_add_revoke(sdp, bd);
58 gfs2_log_unlock(sdp);
60 spin_lock(&sdp->sd_ail_lock);
62 gfs2_assert_withdraw(sdp, !atomic_read(&gl->gl_ail_count));
63 spin_unlock(&sdp->sd_ail_lock);
67 static void gfs2_ail_empty_gl(struct gfs2_glock *gl)
69 struct gfs2_sbd *sdp = gl->gl_sbd;
70 struct gfs2_trans tr;
72 memset(&tr, 0, sizeof(tr));
73 tr.tr_revokes = atomic_read(&gl->gl_ail_count);
75 if (!tr.tr_revokes)
76 return;
78 /* A shortened, inline version of gfs2_trans_begin() */
79 tr.tr_reserved = 1 + gfs2_struct2blk(sdp, tr.tr_revokes, sizeof(u64));
80 tr.tr_ip = (unsigned long)__builtin_return_address(0);
81 INIT_LIST_HEAD(&tr.tr_list_buf);
82 gfs2_log_reserve(sdp, tr.tr_reserved);
83 BUG_ON(current->journal_info);
84 current->journal_info = &tr;
86 __gfs2_ail_flush(gl);
88 gfs2_trans_end(sdp);
89 gfs2_log_flush(sdp, NULL);
92 void gfs2_ail_flush(struct gfs2_glock *gl)
94 struct gfs2_sbd *sdp = gl->gl_sbd;
95 unsigned int revokes = atomic_read(&gl->gl_ail_count);
96 int ret;
98 if (!revokes)
99 return;
101 ret = gfs2_trans_begin(sdp, 0, revokes);
102 if (ret)
103 return;
104 __gfs2_ail_flush(gl);
105 gfs2_trans_end(sdp);
106 gfs2_log_flush(sdp, NULL);
110 * rgrp_go_sync - sync out the metadata for this glock
111 * @gl: the glock
113 * Called when demoting or unlocking an EX glock. We must flush
114 * to disk all dirty buffers/pages relating to this glock, and must not
115 * not return to caller to demote/unlock the glock until I/O is complete.
118 static void rgrp_go_sync(struct gfs2_glock *gl)
120 struct address_space *metamapping = gfs2_glock2aspace(gl);
121 int error;
123 if (!test_and_clear_bit(GLF_DIRTY, &gl->gl_flags))
124 return;
125 BUG_ON(gl->gl_state != LM_ST_EXCLUSIVE);
127 gfs2_log_flush(gl->gl_sbd, gl);
128 filemap_fdatawrite(metamapping);
129 error = filemap_fdatawait(metamapping);
130 mapping_set_error(metamapping, error);
131 gfs2_ail_empty_gl(gl);
135 * rgrp_go_inval - invalidate the metadata for this glock
136 * @gl: the glock
137 * @flags:
139 * We never used LM_ST_DEFERRED with resource groups, so that we
140 * should always see the metadata flag set here.
144 static void rgrp_go_inval(struct gfs2_glock *gl, int flags)
146 struct address_space *mapping = gfs2_glock2aspace(gl);
148 BUG_ON(!(flags & DIO_METADATA));
149 gfs2_assert_withdraw(gl->gl_sbd, !atomic_read(&gl->gl_ail_count));
150 truncate_inode_pages(mapping, 0);
152 if (gl->gl_object) {
153 struct gfs2_rgrpd *rgd = (struct gfs2_rgrpd *)gl->gl_object;
154 rgd->rd_flags &= ~GFS2_RDF_UPTODATE;
159 * inode_go_sync - Sync the dirty data and/or metadata for an inode glock
160 * @gl: the glock protecting the inode
164 static void inode_go_sync(struct gfs2_glock *gl)
166 struct gfs2_inode *ip = gl->gl_object;
167 struct address_space *metamapping = gfs2_glock2aspace(gl);
168 int error;
170 if (ip && !S_ISREG(ip->i_inode.i_mode))
171 ip = NULL;
172 if (ip && test_and_clear_bit(GIF_SW_PAGED, &ip->i_flags))
173 unmap_shared_mapping_range(ip->i_inode.i_mapping, 0, 0);
174 if (!test_and_clear_bit(GLF_DIRTY, &gl->gl_flags))
175 return;
177 BUG_ON(gl->gl_state != LM_ST_EXCLUSIVE);
179 gfs2_log_flush(gl->gl_sbd, gl);
180 filemap_fdatawrite(metamapping);
181 if (ip) {
182 struct address_space *mapping = ip->i_inode.i_mapping;
183 filemap_fdatawrite(mapping);
184 error = filemap_fdatawait(mapping);
185 mapping_set_error(mapping, error);
187 error = filemap_fdatawait(metamapping);
188 mapping_set_error(metamapping, error);
189 gfs2_ail_empty_gl(gl);
191 * Writeback of the data mapping may cause the dirty flag to be set
192 * so we have to clear it again here.
194 smp_mb__before_clear_bit();
195 clear_bit(GLF_DIRTY, &gl->gl_flags);
199 * inode_go_inval - prepare a inode glock to be released
200 * @gl: the glock
201 * @flags:
203 * Normally we invlidate everything, but if we are moving into
204 * LM_ST_DEFERRED from LM_ST_SHARED or LM_ST_EXCLUSIVE then we
205 * can keep hold of the metadata, since it won't have changed.
209 static void inode_go_inval(struct gfs2_glock *gl, int flags)
211 struct gfs2_inode *ip = gl->gl_object;
213 gfs2_assert_withdraw(gl->gl_sbd, !atomic_read(&gl->gl_ail_count));
215 if (flags & DIO_METADATA) {
216 struct address_space *mapping = gfs2_glock2aspace(gl);
217 truncate_inode_pages(mapping, 0);
218 if (ip) {
219 set_bit(GIF_INVALID, &ip->i_flags);
220 forget_all_cached_acls(&ip->i_inode);
224 if (ip == GFS2_I(gl->gl_sbd->sd_rindex))
225 gl->gl_sbd->sd_rindex_uptodate = 0;
226 if (ip && S_ISREG(ip->i_inode.i_mode))
227 truncate_inode_pages(ip->i_inode.i_mapping, 0);
231 * inode_go_demote_ok - Check to see if it's ok to unlock an inode glock
232 * @gl: the glock
234 * Returns: 1 if it's ok
237 static int inode_go_demote_ok(const struct gfs2_glock *gl)
239 struct gfs2_sbd *sdp = gl->gl_sbd;
240 struct gfs2_holder *gh;
242 if (sdp->sd_jindex == gl->gl_object || sdp->sd_rindex == gl->gl_object)
243 return 0;
245 if (!list_empty(&gl->gl_holders)) {
246 gh = list_entry(gl->gl_holders.next, struct gfs2_holder, gh_list);
247 if (gh->gh_list.next != &gl->gl_holders)
248 return 0;
251 return 1;
255 * gfs2_set_nlink - Set the inode's link count based on on-disk info
256 * @inode: The inode in question
257 * @nlink: The link count
259 * If the link count has hit zero, it must never be raised, whatever the
260 * on-disk inode might say. When new struct inodes are created the link
261 * count is set to 1, so that we can safely use this test even when reading
262 * in on disk information for the first time.
265 static void gfs2_set_nlink(struct inode *inode, u32 nlink)
268 * We will need to review setting the nlink count here in the
269 * light of the forthcoming ro bind mount work. This is a reminder
270 * to do that.
272 if ((inode->i_nlink != nlink) && (inode->i_nlink != 0)) {
273 if (nlink == 0)
274 clear_nlink(inode);
275 else
276 inode->i_nlink = nlink;
280 static int gfs2_dinode_in(struct gfs2_inode *ip, const void *buf)
282 const struct gfs2_dinode *str = buf;
283 struct timespec atime;
284 u16 height, depth;
286 if (unlikely(ip->i_no_addr != be64_to_cpu(str->di_num.no_addr)))
287 goto corrupt;
288 ip->i_no_formal_ino = be64_to_cpu(str->di_num.no_formal_ino);
289 ip->i_inode.i_mode = be32_to_cpu(str->di_mode);
290 ip->i_inode.i_rdev = 0;
291 switch (ip->i_inode.i_mode & S_IFMT) {
292 case S_IFBLK:
293 case S_IFCHR:
294 ip->i_inode.i_rdev = MKDEV(be32_to_cpu(str->di_major),
295 be32_to_cpu(str->di_minor));
296 break;
299 ip->i_inode.i_uid = be32_to_cpu(str->di_uid);
300 ip->i_inode.i_gid = be32_to_cpu(str->di_gid);
301 gfs2_set_nlink(&ip->i_inode, be32_to_cpu(str->di_nlink));
302 i_size_write(&ip->i_inode, be64_to_cpu(str->di_size));
303 gfs2_set_inode_blocks(&ip->i_inode, be64_to_cpu(str->di_blocks));
304 atime.tv_sec = be64_to_cpu(str->di_atime);
305 atime.tv_nsec = be32_to_cpu(str->di_atime_nsec);
306 if (timespec_compare(&ip->i_inode.i_atime, &atime) < 0)
307 ip->i_inode.i_atime = atime;
308 ip->i_inode.i_mtime.tv_sec = be64_to_cpu(str->di_mtime);
309 ip->i_inode.i_mtime.tv_nsec = be32_to_cpu(str->di_mtime_nsec);
310 ip->i_inode.i_ctime.tv_sec = be64_to_cpu(str->di_ctime);
311 ip->i_inode.i_ctime.tv_nsec = be32_to_cpu(str->di_ctime_nsec);
313 ip->i_goal = be64_to_cpu(str->di_goal_meta);
314 ip->i_generation = be64_to_cpu(str->di_generation);
316 ip->i_diskflags = be32_to_cpu(str->di_flags);
317 gfs2_set_inode_flags(&ip->i_inode);
318 height = be16_to_cpu(str->di_height);
319 if (unlikely(height > GFS2_MAX_META_HEIGHT))
320 goto corrupt;
321 ip->i_height = (u8)height;
323 depth = be16_to_cpu(str->di_depth);
324 if (unlikely(depth > GFS2_DIR_MAX_DEPTH))
325 goto corrupt;
326 ip->i_depth = (u8)depth;
327 ip->i_entries = be32_to_cpu(str->di_entries);
329 ip->i_eattr = be64_to_cpu(str->di_eattr);
330 if (S_ISREG(ip->i_inode.i_mode))
331 gfs2_set_aops(&ip->i_inode);
333 return 0;
334 corrupt:
335 gfs2_consist_inode(ip);
336 return -EIO;
340 * gfs2_inode_refresh - Refresh the incore copy of the dinode
341 * @ip: The GFS2 inode
343 * Returns: errno
346 int gfs2_inode_refresh(struct gfs2_inode *ip)
348 struct buffer_head *dibh;
349 int error;
351 error = gfs2_meta_inode_buffer(ip, &dibh);
352 if (error)
353 return error;
355 if (gfs2_metatype_check(GFS2_SB(&ip->i_inode), dibh, GFS2_METATYPE_DI)) {
356 brelse(dibh);
357 return -EIO;
360 error = gfs2_dinode_in(ip, dibh->b_data);
361 brelse(dibh);
362 clear_bit(GIF_INVALID, &ip->i_flags);
364 return error;
368 * inode_go_lock - operation done after an inode lock is locked by a process
369 * @gl: the glock
370 * @flags:
372 * Returns: errno
375 static int inode_go_lock(struct gfs2_holder *gh)
377 struct gfs2_glock *gl = gh->gh_gl;
378 struct gfs2_sbd *sdp = gl->gl_sbd;
379 struct gfs2_inode *ip = gl->gl_object;
380 int error = 0;
382 if (!ip || (gh->gh_flags & GL_SKIP))
383 return 0;
385 if (test_bit(GIF_INVALID, &ip->i_flags)) {
386 error = gfs2_inode_refresh(ip);
387 if (error)
388 return error;
391 if ((ip->i_diskflags & GFS2_DIF_TRUNC_IN_PROG) &&
392 (gl->gl_state == LM_ST_EXCLUSIVE) &&
393 (gh->gh_state == LM_ST_EXCLUSIVE)) {
394 spin_lock(&sdp->sd_trunc_lock);
395 if (list_empty(&ip->i_trunc_list))
396 list_add(&sdp->sd_trunc_list, &ip->i_trunc_list);
397 spin_unlock(&sdp->sd_trunc_lock);
398 wake_up(&sdp->sd_quota_wait);
399 return 1;
402 return error;
406 * inode_go_dump - print information about an inode
407 * @seq: The iterator
408 * @ip: the inode
410 * Returns: 0 on success, -ENOBUFS when we run out of space
413 static int inode_go_dump(struct seq_file *seq, const struct gfs2_glock *gl)
415 const struct gfs2_inode *ip = gl->gl_object;
416 if (ip == NULL)
417 return 0;
418 gfs2_print_dbg(seq, " I: n:%llu/%llu t:%u f:0x%02lx d:0x%08x s:%llu\n",
419 (unsigned long long)ip->i_no_formal_ino,
420 (unsigned long long)ip->i_no_addr,
421 IF2DT(ip->i_inode.i_mode), ip->i_flags,
422 (unsigned int)ip->i_diskflags,
423 (unsigned long long)i_size_read(&ip->i_inode));
424 return 0;
428 * rgrp_go_lock - operation done after an rgrp lock is locked by
429 * a first holder on this node.
430 * @gl: the glock
431 * @flags:
433 * Returns: errno
436 static int rgrp_go_lock(struct gfs2_holder *gh)
438 return gfs2_rgrp_bh_get(gh->gh_gl->gl_object);
442 * rgrp_go_unlock - operation done before an rgrp lock is unlocked by
443 * a last holder on this node.
444 * @gl: the glock
445 * @flags:
449 static void rgrp_go_unlock(struct gfs2_holder *gh)
451 gfs2_rgrp_bh_put(gh->gh_gl->gl_object);
455 * trans_go_sync - promote/demote the transaction glock
456 * @gl: the glock
457 * @state: the requested state
458 * @flags:
462 static void trans_go_sync(struct gfs2_glock *gl)
464 struct gfs2_sbd *sdp = gl->gl_sbd;
466 if (gl->gl_state != LM_ST_UNLOCKED &&
467 test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
468 gfs2_meta_syncfs(sdp);
469 gfs2_log_shutdown(sdp);
474 * trans_go_xmote_bh - After promoting/demoting the transaction glock
475 * @gl: the glock
479 static int trans_go_xmote_bh(struct gfs2_glock *gl, struct gfs2_holder *gh)
481 struct gfs2_sbd *sdp = gl->gl_sbd;
482 struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
483 struct gfs2_glock *j_gl = ip->i_gl;
484 struct gfs2_log_header_host head;
485 int error;
487 if (test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
488 j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
490 error = gfs2_find_jhead(sdp->sd_jdesc, &head);
491 if (error)
492 gfs2_consist(sdp);
493 if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT))
494 gfs2_consist(sdp);
496 /* Initialize some head of the log stuff */
497 if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) {
498 sdp->sd_log_sequence = head.lh_sequence + 1;
499 gfs2_log_pointers_init(sdp, head.lh_blkno);
502 return 0;
506 * trans_go_demote_ok
507 * @gl: the glock
509 * Always returns 0
512 static int trans_go_demote_ok(const struct gfs2_glock *gl)
514 return 0;
518 * iopen_go_callback - schedule the dcache entry for the inode to be deleted
519 * @gl: the glock
521 * gl_spin lock is held while calling this
523 static void iopen_go_callback(struct gfs2_glock *gl)
525 struct gfs2_inode *ip = (struct gfs2_inode *)gl->gl_object;
526 struct gfs2_sbd *sdp = gl->gl_sbd;
528 if (sdp->sd_vfs->s_flags & MS_RDONLY)
529 return;
531 if (gl->gl_demote_state == LM_ST_UNLOCKED &&
532 gl->gl_state == LM_ST_SHARED && ip) {
533 gfs2_glock_hold(gl);
534 if (queue_work(gfs2_delete_workqueue, &gl->gl_delete) == 0)
535 gfs2_glock_put_nolock(gl);
539 const struct gfs2_glock_operations gfs2_meta_glops = {
540 .go_type = LM_TYPE_META,
543 const struct gfs2_glock_operations gfs2_inode_glops = {
544 .go_xmote_th = inode_go_sync,
545 .go_inval = inode_go_inval,
546 .go_demote_ok = inode_go_demote_ok,
547 .go_lock = inode_go_lock,
548 .go_dump = inode_go_dump,
549 .go_type = LM_TYPE_INODE,
550 .go_min_hold_time = HZ / 5,
551 .go_flags = GLOF_ASPACE,
554 const struct gfs2_glock_operations gfs2_rgrp_glops = {
555 .go_xmote_th = rgrp_go_sync,
556 .go_inval = rgrp_go_inval,
557 .go_lock = rgrp_go_lock,
558 .go_unlock = rgrp_go_unlock,
559 .go_dump = gfs2_rgrp_dump,
560 .go_type = LM_TYPE_RGRP,
561 .go_min_hold_time = HZ / 5,
562 .go_flags = GLOF_ASPACE,
565 const struct gfs2_glock_operations gfs2_trans_glops = {
566 .go_xmote_th = trans_go_sync,
567 .go_xmote_bh = trans_go_xmote_bh,
568 .go_demote_ok = trans_go_demote_ok,
569 .go_type = LM_TYPE_NONDISK,
572 const struct gfs2_glock_operations gfs2_iopen_glops = {
573 .go_type = LM_TYPE_IOPEN,
574 .go_callback = iopen_go_callback,
577 const struct gfs2_glock_operations gfs2_flock_glops = {
578 .go_type = LM_TYPE_FLOCK,
581 const struct gfs2_glock_operations gfs2_nondisk_glops = {
582 .go_type = LM_TYPE_NONDISK,
585 const struct gfs2_glock_operations gfs2_quota_glops = {
586 .go_type = LM_TYPE_QUOTA,
589 const struct gfs2_glock_operations gfs2_journal_glops = {
590 .go_type = LM_TYPE_JOURNAL,
593 const struct gfs2_glock_operations *gfs2_glops_list[] = {
594 [LM_TYPE_META] = &gfs2_meta_glops,
595 [LM_TYPE_INODE] = &gfs2_inode_glops,
596 [LM_TYPE_RGRP] = &gfs2_rgrp_glops,
597 [LM_TYPE_IOPEN] = &gfs2_iopen_glops,
598 [LM_TYPE_FLOCK] = &gfs2_flock_glops,
599 [LM_TYPE_NONDISK] = &gfs2_nondisk_glops,
600 [LM_TYPE_QUOTA] = &gfs2_quota_glops,
601 [LM_TYPE_JOURNAL] = &gfs2_journal_glops,