md: fix up switching md arrays between read-only and read-write
[linux-2.6/mini2440.git] / fs / gfs2 / glops.c
blobd31badadef8f929bd5e5bec992cf7c717b674ddb
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/slab.h>
11 #include <linux/spinlock.h>
12 #include <linux/completion.h>
13 #include <linux/buffer_head.h>
14 #include <linux/gfs2_ondisk.h>
15 #include <linux/lm_interface.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 * ail_empty_gl - 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_empty_gl(struct gfs2_glock *gl)
39 struct gfs2_sbd *sdp = gl->gl_sbd;
40 unsigned int blocks;
41 struct list_head *head = &gl->gl_ail_list;
42 struct gfs2_bufdata *bd;
43 struct buffer_head *bh;
44 int error;
46 blocks = atomic_read(&gl->gl_ail_count);
47 if (!blocks)
48 return;
50 error = gfs2_trans_begin(sdp, 0, blocks);
51 if (gfs2_assert_withdraw(sdp, !error))
52 return;
54 gfs2_log_lock(sdp);
55 while (!list_empty(head)) {
56 bd = list_entry(head->next, struct gfs2_bufdata,
57 bd_ail_gl_list);
58 bh = bd->bd_bh;
59 gfs2_remove_from_ail(bd);
60 bd->bd_bh = NULL;
61 bh->b_private = NULL;
62 bd->bd_blkno = bh->b_blocknr;
63 gfs2_assert_withdraw(sdp, !buffer_busy(bh));
64 gfs2_trans_add_revoke(sdp, bd);
66 gfs2_assert_withdraw(sdp, !atomic_read(&gl->gl_ail_count));
67 gfs2_log_unlock(sdp);
69 gfs2_trans_end(sdp);
70 gfs2_log_flush(sdp, NULL);
73 /**
74 * gfs2_pte_inval - Sync and invalidate all PTEs associated with a glock
75 * @gl: the glock
79 static void gfs2_pte_inval(struct gfs2_glock *gl)
81 struct gfs2_inode *ip;
82 struct inode *inode;
84 ip = gl->gl_object;
85 inode = &ip->i_inode;
86 if (!ip || !S_ISREG(inode->i_mode))
87 return;
89 unmap_shared_mapping_range(inode->i_mapping, 0, 0);
90 if (test_bit(GIF_SW_PAGED, &ip->i_flags))
91 set_bit(GLF_DIRTY, &gl->gl_flags);
95 /**
96 * meta_go_sync - sync out the metadata for this glock
97 * @gl: the glock
99 * Called when demoting or unlocking an EX glock. We must flush
100 * to disk all dirty buffers/pages relating to this glock, and must not
101 * not return to caller to demote/unlock the glock until I/O is complete.
104 static void meta_go_sync(struct gfs2_glock *gl)
106 if (gl->gl_state != LM_ST_EXCLUSIVE)
107 return;
109 if (test_and_clear_bit(GLF_DIRTY, &gl->gl_flags)) {
110 gfs2_log_flush(gl->gl_sbd, gl);
111 gfs2_meta_sync(gl);
112 gfs2_ail_empty_gl(gl);
117 * meta_go_inval - invalidate the metadata for this glock
118 * @gl: the glock
119 * @flags:
123 static void meta_go_inval(struct gfs2_glock *gl, int flags)
125 if (!(flags & DIO_METADATA))
126 return;
128 gfs2_meta_inval(gl);
129 if (gl->gl_object == GFS2_I(gl->gl_sbd->sd_rindex))
130 gl->gl_sbd->sd_rindex_uptodate = 0;
131 else if (gl->gl_ops == &gfs2_rgrp_glops && gl->gl_object) {
132 struct gfs2_rgrpd *rgd = (struct gfs2_rgrpd *)gl->gl_object;
134 rgd->rd_flags &= ~GFS2_RDF_UPTODATE;
139 * inode_go_sync - Sync the dirty data and/or metadata for an inode glock
140 * @gl: the glock protecting the inode
144 static void inode_go_sync(struct gfs2_glock *gl)
146 struct gfs2_inode *ip = gl->gl_object;
147 struct address_space *metamapping = gl->gl_aspace->i_mapping;
148 int error;
150 if (gl->gl_state != LM_ST_UNLOCKED)
151 gfs2_pte_inval(gl);
152 if (gl->gl_state != LM_ST_EXCLUSIVE)
153 return;
155 if (ip && !S_ISREG(ip->i_inode.i_mode))
156 ip = NULL;
158 if (test_bit(GLF_DIRTY, &gl->gl_flags)) {
159 gfs2_log_flush(gl->gl_sbd, gl);
160 filemap_fdatawrite(metamapping);
161 if (ip) {
162 struct address_space *mapping = ip->i_inode.i_mapping;
163 filemap_fdatawrite(mapping);
164 error = filemap_fdatawait(mapping);
165 mapping_set_error(mapping, error);
167 error = filemap_fdatawait(metamapping);
168 mapping_set_error(metamapping, error);
169 clear_bit(GLF_DIRTY, &gl->gl_flags);
170 gfs2_ail_empty_gl(gl);
175 * inode_go_xmote_bh - After promoting/demoting a glock
176 * @gl: the glock
180 static void inode_go_xmote_bh(struct gfs2_glock *gl)
182 struct gfs2_holder *gh = gl->gl_req_gh;
183 struct buffer_head *bh;
184 int error;
186 if (gl->gl_state != LM_ST_UNLOCKED &&
187 (!gh || !(gh->gh_flags & GL_SKIP))) {
188 error = gfs2_meta_read(gl, gl->gl_name.ln_number, 0, &bh);
189 if (!error)
190 brelse(bh);
195 * inode_go_inval - prepare a inode glock to be released
196 * @gl: the glock
197 * @flags:
201 static void inode_go_inval(struct gfs2_glock *gl, int flags)
203 struct gfs2_inode *ip = gl->gl_object;
204 int meta = (flags & DIO_METADATA);
206 if (meta) {
207 gfs2_meta_inval(gl);
208 if (ip)
209 set_bit(GIF_INVALID, &ip->i_flags);
212 if (ip && S_ISREG(ip->i_inode.i_mode))
213 truncate_inode_pages(ip->i_inode.i_mapping, 0);
217 * inode_go_demote_ok - Check to see if it's ok to unlock an inode glock
218 * @gl: the glock
220 * Returns: 1 if it's ok
223 static int inode_go_demote_ok(struct gfs2_glock *gl)
225 struct gfs2_sbd *sdp = gl->gl_sbd;
226 int demote = 0;
228 if (!gl->gl_object && !gl->gl_aspace->i_mapping->nrpages)
229 demote = 1;
230 else if (!sdp->sd_args.ar_localcaching &&
231 time_after_eq(jiffies, gl->gl_stamp +
232 gfs2_tune_get(sdp, gt_demote_secs) * HZ))
233 demote = 1;
235 return demote;
239 * inode_go_lock - operation done after an inode lock is locked by a process
240 * @gl: the glock
241 * @flags:
243 * Returns: errno
246 static int inode_go_lock(struct gfs2_holder *gh)
248 struct gfs2_glock *gl = gh->gh_gl;
249 struct gfs2_inode *ip = gl->gl_object;
250 int error = 0;
252 if (!ip)
253 return 0;
255 if (test_bit(GIF_INVALID, &ip->i_flags)) {
256 error = gfs2_inode_refresh(ip);
257 if (error)
258 return error;
261 if ((ip->i_di.di_flags & GFS2_DIF_TRUNC_IN_PROG) &&
262 (gl->gl_state == LM_ST_EXCLUSIVE) &&
263 (gh->gh_state == LM_ST_EXCLUSIVE))
264 error = gfs2_truncatei_resume(ip);
266 return error;
270 * rgrp_go_demote_ok - Check to see if it's ok to unlock a RG's glock
271 * @gl: the glock
273 * Returns: 1 if it's ok
276 static int rgrp_go_demote_ok(struct gfs2_glock *gl)
278 return !gl->gl_aspace->i_mapping->nrpages;
282 * rgrp_go_lock - operation done after an rgrp lock is locked by
283 * a first holder on this node.
284 * @gl: the glock
285 * @flags:
287 * Returns: errno
290 static int rgrp_go_lock(struct gfs2_holder *gh)
292 return gfs2_rgrp_bh_get(gh->gh_gl->gl_object);
296 * rgrp_go_unlock - operation done before an rgrp lock is unlocked by
297 * a last holder on this node.
298 * @gl: the glock
299 * @flags:
303 static void rgrp_go_unlock(struct gfs2_holder *gh)
305 gfs2_rgrp_bh_put(gh->gh_gl->gl_object);
309 * trans_go_sync - promote/demote the transaction glock
310 * @gl: the glock
311 * @state: the requested state
312 * @flags:
316 static void trans_go_sync(struct gfs2_glock *gl)
318 struct gfs2_sbd *sdp = gl->gl_sbd;
320 if (gl->gl_state != LM_ST_UNLOCKED &&
321 test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
322 gfs2_meta_syncfs(sdp);
323 gfs2_log_shutdown(sdp);
328 * trans_go_xmote_bh - After promoting/demoting the transaction glock
329 * @gl: the glock
333 static void trans_go_xmote_bh(struct gfs2_glock *gl)
335 struct gfs2_sbd *sdp = gl->gl_sbd;
336 struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
337 struct gfs2_glock *j_gl = ip->i_gl;
338 struct gfs2_log_header_host head;
339 int error;
341 if (gl->gl_state != LM_ST_UNLOCKED &&
342 test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
343 j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
345 error = gfs2_find_jhead(sdp->sd_jdesc, &head);
346 if (error)
347 gfs2_consist(sdp);
348 if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT))
349 gfs2_consist(sdp);
351 /* Initialize some head of the log stuff */
352 if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) {
353 sdp->sd_log_sequence = head.lh_sequence + 1;
354 gfs2_log_pointers_init(sdp, head.lh_blkno);
360 * quota_go_demote_ok - Check to see if it's ok to unlock a quota glock
361 * @gl: the glock
363 * Returns: 1 if it's ok
366 static int quota_go_demote_ok(struct gfs2_glock *gl)
368 return !atomic_read(&gl->gl_lvb_count);
371 const struct gfs2_glock_operations gfs2_meta_glops = {
372 .go_xmote_th = meta_go_sync,
373 .go_type = LM_TYPE_META,
376 const struct gfs2_glock_operations gfs2_inode_glops = {
377 .go_xmote_th = inode_go_sync,
378 .go_xmote_bh = inode_go_xmote_bh,
379 .go_inval = inode_go_inval,
380 .go_demote_ok = inode_go_demote_ok,
381 .go_lock = inode_go_lock,
382 .go_type = LM_TYPE_INODE,
383 .go_min_hold_time = HZ / 10,
386 const struct gfs2_glock_operations gfs2_rgrp_glops = {
387 .go_xmote_th = meta_go_sync,
388 .go_inval = meta_go_inval,
389 .go_demote_ok = rgrp_go_demote_ok,
390 .go_lock = rgrp_go_lock,
391 .go_unlock = rgrp_go_unlock,
392 .go_type = LM_TYPE_RGRP,
393 .go_min_hold_time = HZ / 10,
396 const struct gfs2_glock_operations gfs2_trans_glops = {
397 .go_xmote_th = trans_go_sync,
398 .go_xmote_bh = trans_go_xmote_bh,
399 .go_type = LM_TYPE_NONDISK,
402 const struct gfs2_glock_operations gfs2_iopen_glops = {
403 .go_type = LM_TYPE_IOPEN,
406 const struct gfs2_glock_operations gfs2_flock_glops = {
407 .go_type = LM_TYPE_FLOCK,
410 const struct gfs2_glock_operations gfs2_nondisk_glops = {
411 .go_type = LM_TYPE_NONDISK,
414 const struct gfs2_glock_operations gfs2_quota_glops = {
415 .go_demote_ok = quota_go_demote_ok,
416 .go_type = LM_TYPE_QUOTA,
419 const struct gfs2_glock_operations gfs2_journal_glops = {
420 .go_type = LM_TYPE_JOURNAL,