dz: clean up and improve the setup of termios settings
[linux-2.6/openmoko-kernel/knife-kernel.git] / fs / gfs2 / glops.c
blobc663b7a0f410a3c9c2a6c2136a722be8cf429b09
1 /*
2 * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
3 * Copyright (C) 2004-2006 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 gl->gl_vn++;
133 * inode_go_sync - Sync the dirty data and/or metadata for an inode glock
134 * @gl: the glock protecting the inode
138 static void inode_go_sync(struct gfs2_glock *gl)
140 struct gfs2_inode *ip = gl->gl_object;
141 struct address_space *metamapping = gl->gl_aspace->i_mapping;
142 int error;
144 if (gl->gl_state != LM_ST_UNLOCKED)
145 gfs2_pte_inval(gl);
146 if (gl->gl_state != LM_ST_EXCLUSIVE)
147 return;
149 if (ip && !S_ISREG(ip->i_inode.i_mode))
150 ip = NULL;
152 if (test_bit(GLF_DIRTY, &gl->gl_flags)) {
153 gfs2_log_flush(gl->gl_sbd, gl);
154 filemap_fdatawrite(metamapping);
155 if (ip) {
156 struct address_space *mapping = ip->i_inode.i_mapping;
157 filemap_fdatawrite(mapping);
158 error = filemap_fdatawait(mapping);
159 mapping_set_error(mapping, error);
161 error = filemap_fdatawait(metamapping);
162 mapping_set_error(metamapping, error);
163 clear_bit(GLF_DIRTY, &gl->gl_flags);
164 gfs2_ail_empty_gl(gl);
169 * inode_go_xmote_bh - After promoting/demoting a glock
170 * @gl: the glock
174 static void inode_go_xmote_bh(struct gfs2_glock *gl)
176 struct gfs2_holder *gh = gl->gl_req_gh;
177 struct buffer_head *bh;
178 int error;
180 if (gl->gl_state != LM_ST_UNLOCKED &&
181 (!gh || !(gh->gh_flags & GL_SKIP))) {
182 error = gfs2_meta_read(gl, gl->gl_name.ln_number, 0, &bh);
183 if (!error)
184 brelse(bh);
189 * inode_go_inval - prepare a inode glock to be released
190 * @gl: the glock
191 * @flags:
195 static void inode_go_inval(struct gfs2_glock *gl, int flags)
197 struct gfs2_inode *ip = gl->gl_object;
198 int meta = (flags & DIO_METADATA);
200 if (meta) {
201 gfs2_meta_inval(gl);
202 if (ip)
203 set_bit(GIF_INVALID, &ip->i_flags);
206 if (ip && S_ISREG(ip->i_inode.i_mode))
207 truncate_inode_pages(ip->i_inode.i_mapping, 0);
211 * inode_go_demote_ok - Check to see if it's ok to unlock an inode glock
212 * @gl: the glock
214 * Returns: 1 if it's ok
217 static int inode_go_demote_ok(struct gfs2_glock *gl)
219 struct gfs2_sbd *sdp = gl->gl_sbd;
220 int demote = 0;
222 if (!gl->gl_object && !gl->gl_aspace->i_mapping->nrpages)
223 demote = 1;
224 else if (!sdp->sd_args.ar_localcaching &&
225 time_after_eq(jiffies, gl->gl_stamp +
226 gfs2_tune_get(sdp, gt_demote_secs) * HZ))
227 demote = 1;
229 return demote;
233 * inode_go_lock - operation done after an inode lock is locked by a process
234 * @gl: the glock
235 * @flags:
237 * Returns: errno
240 static int inode_go_lock(struct gfs2_holder *gh)
242 struct gfs2_glock *gl = gh->gh_gl;
243 struct gfs2_inode *ip = gl->gl_object;
244 int error = 0;
246 if (!ip)
247 return 0;
249 if (test_bit(GIF_INVALID, &ip->i_flags)) {
250 error = gfs2_inode_refresh(ip);
251 if (error)
252 return error;
255 if ((ip->i_di.di_flags & GFS2_DIF_TRUNC_IN_PROG) &&
256 (gl->gl_state == LM_ST_EXCLUSIVE) &&
257 (gh->gh_state == LM_ST_EXCLUSIVE))
258 error = gfs2_truncatei_resume(ip);
260 return error;
264 * rgrp_go_demote_ok - Check to see if it's ok to unlock a RG's glock
265 * @gl: the glock
267 * Returns: 1 if it's ok
270 static int rgrp_go_demote_ok(struct gfs2_glock *gl)
272 return !gl->gl_aspace->i_mapping->nrpages;
276 * rgrp_go_lock - operation done after an rgrp lock is locked by
277 * a first holder on this node.
278 * @gl: the glock
279 * @flags:
281 * Returns: errno
284 static int rgrp_go_lock(struct gfs2_holder *gh)
286 return gfs2_rgrp_bh_get(gh->gh_gl->gl_object);
290 * rgrp_go_unlock - operation done before an rgrp lock is unlocked by
291 * a last holder on this node.
292 * @gl: the glock
293 * @flags:
297 static void rgrp_go_unlock(struct gfs2_holder *gh)
299 gfs2_rgrp_bh_put(gh->gh_gl->gl_object);
303 * trans_go_sync - promote/demote the transaction glock
304 * @gl: the glock
305 * @state: the requested state
306 * @flags:
310 static void trans_go_sync(struct gfs2_glock *gl)
312 struct gfs2_sbd *sdp = gl->gl_sbd;
314 if (gl->gl_state != LM_ST_UNLOCKED &&
315 test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
316 gfs2_meta_syncfs(sdp);
317 gfs2_log_shutdown(sdp);
322 * trans_go_xmote_bh - After promoting/demoting the transaction glock
323 * @gl: the glock
327 static void trans_go_xmote_bh(struct gfs2_glock *gl)
329 struct gfs2_sbd *sdp = gl->gl_sbd;
330 struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
331 struct gfs2_glock *j_gl = ip->i_gl;
332 struct gfs2_log_header_host head;
333 int error;
335 if (gl->gl_state != LM_ST_UNLOCKED &&
336 test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
337 j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
339 error = gfs2_find_jhead(sdp->sd_jdesc, &head);
340 if (error)
341 gfs2_consist(sdp);
342 if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT))
343 gfs2_consist(sdp);
345 /* Initialize some head of the log stuff */
346 if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) {
347 sdp->sd_log_sequence = head.lh_sequence + 1;
348 gfs2_log_pointers_init(sdp, head.lh_blkno);
354 * quota_go_demote_ok - Check to see if it's ok to unlock a quota glock
355 * @gl: the glock
357 * Returns: 1 if it's ok
360 static int quota_go_demote_ok(struct gfs2_glock *gl)
362 return !atomic_read(&gl->gl_lvb_count);
365 const struct gfs2_glock_operations gfs2_meta_glops = {
366 .go_xmote_th = meta_go_sync,
367 .go_type = LM_TYPE_META,
370 const struct gfs2_glock_operations gfs2_inode_glops = {
371 .go_xmote_th = inode_go_sync,
372 .go_xmote_bh = inode_go_xmote_bh,
373 .go_inval = inode_go_inval,
374 .go_demote_ok = inode_go_demote_ok,
375 .go_lock = inode_go_lock,
376 .go_type = LM_TYPE_INODE,
377 .go_min_hold_time = HZ / 10,
380 const struct gfs2_glock_operations gfs2_rgrp_glops = {
381 .go_xmote_th = meta_go_sync,
382 .go_inval = meta_go_inval,
383 .go_demote_ok = rgrp_go_demote_ok,
384 .go_lock = rgrp_go_lock,
385 .go_unlock = rgrp_go_unlock,
386 .go_type = LM_TYPE_RGRP,
387 .go_min_hold_time = HZ / 10,
390 const struct gfs2_glock_operations gfs2_trans_glops = {
391 .go_xmote_th = trans_go_sync,
392 .go_xmote_bh = trans_go_xmote_bh,
393 .go_type = LM_TYPE_NONDISK,
396 const struct gfs2_glock_operations gfs2_iopen_glops = {
397 .go_type = LM_TYPE_IOPEN,
400 const struct gfs2_glock_operations gfs2_flock_glops = {
401 .go_type = LM_TYPE_FLOCK,
404 const struct gfs2_glock_operations gfs2_nondisk_glops = {
405 .go_type = LM_TYPE_NONDISK,
408 const struct gfs2_glock_operations gfs2_quota_glops = {
409 .go_demote_ok = quota_go_demote_ok,
410 .go_type = LM_TYPE_QUOTA,
413 const struct gfs2_glock_operations gfs2_journal_glops = {
414 .go_type = LM_TYPE_JOURNAL,