linux/fs/gfs2/glops.c
Benjamin Marzinski b524fe646c [GFS2] flush the glock completely in inode_go_sync
Fix for bz #231910
When filemap_fdatawrite() is called on the inode mapping in data=ordered mode,
it will add the glock to the log. In inode_go_sync(), if you do the
gfs2_log_flush() before this, after the filemap_fdatawrite() call, the glock
and its associated data buffers will be on the log again. This means you can
demote a lock from exclusive, without having it flushed from the log. The
attached patch simply moves the gfs2_log_flush up to after the
filemap_fdatawrite() call.

Originally, I tried moving the gfs2_log_flush to after gfs2_meta_sync(), but
that caused me to trip the following assert.

GFS2: fsid=cypher-36:test.0: fatal: assertion "!buffer_busy(bh)" failed
GFS2: fsid=cypher-36:test.0:   function = gfs2_ail_empty_gl, file = fs/gfs2/glops.c, line = 61

It appears that gfs2_log_flush() puts some of the glocks buffers in the busy
state and the filemap_fdatawrite() call is necessary to flush them. This makes
me worry slightly that a related problem could happen because of moving the
gfs2_log_flush() after the initial filemap_fdatawrite(), but I assume that
gfs2_ail_empty_gl() would catch that case as well.

Signed-off-by: Benjamin E. Marzinski <bmarzins@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2007-07-09 08:22:07 +01:00

495 lines
10 KiB
C

/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License version 2.
*/
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/gfs2_ondisk.h>
#include <linux/lm_interface.h>
#include "gfs2.h"
#include "incore.h"
#include "bmap.h"
#include "glock.h"
#include "glops.h"
#include "inode.h"
#include "log.h"
#include "meta_io.h"
#include "recovery.h"
#include "rgrp.h"
#include "util.h"
#include "trans.h"
/**
* ail_empty_gl - remove all buffers for a given lock from the AIL
* @gl: the glock
*
* None of the buffers should be dirty, locked, or pinned.
*/
static void gfs2_ail_empty_gl(struct gfs2_glock *gl)
{
struct gfs2_sbd *sdp = gl->gl_sbd;
unsigned int blocks;
struct list_head *head = &gl->gl_ail_list;
struct gfs2_bufdata *bd;
struct buffer_head *bh;
u64 blkno;
int error;
blocks = atomic_read(&gl->gl_ail_count);
if (!blocks)
return;
error = gfs2_trans_begin(sdp, 0, blocks);
if (gfs2_assert_withdraw(sdp, !error))
return;
gfs2_log_lock(sdp);
while (!list_empty(head)) {
bd = list_entry(head->next, struct gfs2_bufdata,
bd_ail_gl_list);
bh = bd->bd_bh;
blkno = bh->b_blocknr;
gfs2_assert_withdraw(sdp, !buffer_busy(bh));
bd->bd_ail = NULL;
list_del(&bd->bd_ail_st_list);
list_del(&bd->bd_ail_gl_list);
atomic_dec(&gl->gl_ail_count);
brelse(bh);
gfs2_log_unlock(sdp);
gfs2_trans_add_revoke(sdp, blkno);
gfs2_log_lock(sdp);
}
gfs2_assert_withdraw(sdp, !atomic_read(&gl->gl_ail_count));
gfs2_log_unlock(sdp);
gfs2_trans_end(sdp);
gfs2_log_flush(sdp, NULL);
}
/**
* gfs2_pte_inval - Sync and invalidate all PTEs associated with a glock
* @gl: the glock
*
*/
static void gfs2_pte_inval(struct gfs2_glock *gl)
{
struct gfs2_inode *ip;
struct inode *inode;
ip = gl->gl_object;
inode = &ip->i_inode;
if (!ip || !S_ISREG(inode->i_mode))
return;
if (!test_bit(GIF_PAGED, &ip->i_flags))
return;
unmap_shared_mapping_range(inode->i_mapping, 0, 0);
if (test_bit(GIF_SW_PAGED, &ip->i_flags))
set_bit(GLF_DIRTY, &gl->gl_flags);
clear_bit(GIF_SW_PAGED, &ip->i_flags);
}
/**
* meta_go_sync - sync out the metadata for this glock
* @gl: the glock
*
* Called when demoting or unlocking an EX glock. We must flush
* to disk all dirty buffers/pages relating to this glock, and must not
* not return to caller to demote/unlock the glock until I/O is complete.
*/
static void meta_go_sync(struct gfs2_glock *gl)
{
if (gl->gl_state != LM_ST_EXCLUSIVE)
return;
if (test_and_clear_bit(GLF_DIRTY, &gl->gl_flags)) {
gfs2_log_flush(gl->gl_sbd, gl);
gfs2_meta_sync(gl);
gfs2_ail_empty_gl(gl);
}
}
/**
* meta_go_inval - invalidate the metadata for this glock
* @gl: the glock
* @flags:
*
*/
static void meta_go_inval(struct gfs2_glock *gl, int flags)
{
if (!(flags & DIO_METADATA))
return;
gfs2_meta_inval(gl);
gl->gl_vn++;
}
/**
* inode_go_sync - Sync the dirty data and/or metadata for an inode glock
* @gl: the glock protecting the inode
*
*/
static void inode_go_sync(struct gfs2_glock *gl)
{
struct gfs2_inode *ip = gl->gl_object;
if (ip && !S_ISREG(ip->i_inode.i_mode))
ip = NULL;
if (test_bit(GLF_DIRTY, &gl->gl_flags)) {
if (ip)
filemap_fdatawrite(ip->i_inode.i_mapping);
gfs2_log_flush(gl->gl_sbd, gl);
gfs2_meta_sync(gl);
if (ip) {
struct address_space *mapping = ip->i_inode.i_mapping;
int error = filemap_fdatawait(mapping);
mapping_set_error(mapping, error);
}
clear_bit(GLF_DIRTY, &gl->gl_flags);
gfs2_ail_empty_gl(gl);
}
}
/**
* inode_go_xmote_th - promote/demote a glock
* @gl: the glock
* @state: the requested state
* @flags:
*
*/
static void inode_go_xmote_th(struct gfs2_glock *gl)
{
if (gl->gl_state != LM_ST_UNLOCKED)
gfs2_pte_inval(gl);
if (gl->gl_state == LM_ST_EXCLUSIVE)
inode_go_sync(gl);
}
/**
* inode_go_xmote_bh - After promoting/demoting a glock
* @gl: the glock
*
*/
static void inode_go_xmote_bh(struct gfs2_glock *gl)
{
struct gfs2_holder *gh = gl->gl_req_gh;
struct buffer_head *bh;
int error;
if (gl->gl_state != LM_ST_UNLOCKED &&
(!gh || !(gh->gh_flags & GL_SKIP))) {
error = gfs2_meta_read(gl, gl->gl_name.ln_number, 0, &bh);
if (!error)
brelse(bh);
}
}
/**
* inode_go_drop_th - unlock a glock
* @gl: the glock
*
* Invoked from rq_demote().
* Another node needs the lock in EXCLUSIVE mode, or lock (unused for too long)
* is being purged from our node's glock cache; we're dropping lock.
*/
static void inode_go_drop_th(struct gfs2_glock *gl)
{
gfs2_pte_inval(gl);
if (gl->gl_state == LM_ST_EXCLUSIVE)
inode_go_sync(gl);
}
/**
* inode_go_inval - prepare a inode glock to be released
* @gl: the glock
* @flags:
*
*/
static void inode_go_inval(struct gfs2_glock *gl, int flags)
{
struct gfs2_inode *ip = gl->gl_object;
int meta = (flags & DIO_METADATA);
if (meta) {
gfs2_meta_inval(gl);
if (ip)
set_bit(GIF_INVALID, &ip->i_flags);
}
if (ip && S_ISREG(ip->i_inode.i_mode)) {
truncate_inode_pages(ip->i_inode.i_mapping, 0);
clear_bit(GIF_PAGED, &ip->i_flags);
}
}
/**
* inode_go_demote_ok - Check to see if it's ok to unlock an inode glock
* @gl: the glock
*
* Returns: 1 if it's ok
*/
static int inode_go_demote_ok(struct gfs2_glock *gl)
{
struct gfs2_sbd *sdp = gl->gl_sbd;
int demote = 0;
if (!gl->gl_object && !gl->gl_aspace->i_mapping->nrpages)
demote = 1;
else if (!sdp->sd_args.ar_localcaching &&
time_after_eq(jiffies, gl->gl_stamp +
gfs2_tune_get(sdp, gt_demote_secs) * HZ))
demote = 1;
return demote;
}
/**
* inode_go_lock - operation done after an inode lock is locked by a process
* @gl: the glock
* @flags:
*
* Returns: errno
*/
static int inode_go_lock(struct gfs2_holder *gh)
{
struct gfs2_glock *gl = gh->gh_gl;
struct gfs2_inode *ip = gl->gl_object;
int error = 0;
if (!ip)
return 0;
if (test_bit(GIF_INVALID, &ip->i_flags)) {
error = gfs2_inode_refresh(ip);
if (error)
return error;
}
if ((ip->i_di.di_flags & GFS2_DIF_TRUNC_IN_PROG) &&
(gl->gl_state == LM_ST_EXCLUSIVE) &&
(gh->gh_state == LM_ST_EXCLUSIVE))
error = gfs2_truncatei_resume(ip);
return error;
}
/**
* inode_go_unlock - operation done before an inode lock is unlocked by a
* process
* @gl: the glock
* @flags:
*
*/
static void inode_go_unlock(struct gfs2_holder *gh)
{
struct gfs2_glock *gl = gh->gh_gl;
struct gfs2_inode *ip = gl->gl_object;
if (ip)
gfs2_meta_cache_flush(ip);
}
/**
* rgrp_go_demote_ok - Check to see if it's ok to unlock a RG's glock
* @gl: the glock
*
* Returns: 1 if it's ok
*/
static int rgrp_go_demote_ok(struct gfs2_glock *gl)
{
return !gl->gl_aspace->i_mapping->nrpages;
}
/**
* rgrp_go_lock - operation done after an rgrp lock is locked by
* a first holder on this node.
* @gl: the glock
* @flags:
*
* Returns: errno
*/
static int rgrp_go_lock(struct gfs2_holder *gh)
{
return gfs2_rgrp_bh_get(gh->gh_gl->gl_object);
}
/**
* rgrp_go_unlock - operation done before an rgrp lock is unlocked by
* a last holder on this node.
* @gl: the glock
* @flags:
*
*/
static void rgrp_go_unlock(struct gfs2_holder *gh)
{
gfs2_rgrp_bh_put(gh->gh_gl->gl_object);
}
/**
* trans_go_xmote_th - promote/demote the transaction glock
* @gl: the glock
* @state: the requested state
* @flags:
*
*/
static void trans_go_xmote_th(struct gfs2_glock *gl)
{
struct gfs2_sbd *sdp = gl->gl_sbd;
if (gl->gl_state != LM_ST_UNLOCKED &&
test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
gfs2_meta_syncfs(sdp);
gfs2_log_shutdown(sdp);
}
}
/**
* trans_go_xmote_bh - After promoting/demoting the transaction glock
* @gl: the glock
*
*/
static void trans_go_xmote_bh(struct gfs2_glock *gl)
{
struct gfs2_sbd *sdp = gl->gl_sbd;
struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
struct gfs2_glock *j_gl = ip->i_gl;
struct gfs2_log_header_host head;
int error;
if (gl->gl_state != LM_ST_UNLOCKED &&
test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
gfs2_meta_cache_flush(GFS2_I(sdp->sd_jdesc->jd_inode));
j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
error = gfs2_find_jhead(sdp->sd_jdesc, &head);
if (error)
gfs2_consist(sdp);
if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT))
gfs2_consist(sdp);
/* Initialize some head of the log stuff */
if (!test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) {
sdp->sd_log_sequence = head.lh_sequence + 1;
gfs2_log_pointers_init(sdp, head.lh_blkno);
}
}
}
/**
* trans_go_drop_th - unlock the transaction glock
* @gl: the glock
*
* We want to sync the device even with localcaching. Remember
* that localcaching journal replay only marks buffers dirty.
*/
static void trans_go_drop_th(struct gfs2_glock *gl)
{
struct gfs2_sbd *sdp = gl->gl_sbd;
if (test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
gfs2_meta_syncfs(sdp);
gfs2_log_shutdown(sdp);
}
}
/**
* quota_go_demote_ok - Check to see if it's ok to unlock a quota glock
* @gl: the glock
*
* Returns: 1 if it's ok
*/
static int quota_go_demote_ok(struct gfs2_glock *gl)
{
return !atomic_read(&gl->gl_lvb_count);
}
const struct gfs2_glock_operations gfs2_meta_glops = {
.go_xmote_th = meta_go_sync,
.go_drop_th = meta_go_sync,
.go_type = LM_TYPE_META,
};
const struct gfs2_glock_operations gfs2_inode_glops = {
.go_xmote_th = inode_go_xmote_th,
.go_xmote_bh = inode_go_xmote_bh,
.go_drop_th = inode_go_drop_th,
.go_inval = inode_go_inval,
.go_demote_ok = inode_go_demote_ok,
.go_lock = inode_go_lock,
.go_unlock = inode_go_unlock,
.go_type = LM_TYPE_INODE,
};
const struct gfs2_glock_operations gfs2_rgrp_glops = {
.go_xmote_th = meta_go_sync,
.go_drop_th = meta_go_sync,
.go_inval = meta_go_inval,
.go_demote_ok = rgrp_go_demote_ok,
.go_lock = rgrp_go_lock,
.go_unlock = rgrp_go_unlock,
.go_type = LM_TYPE_RGRP,
};
const struct gfs2_glock_operations gfs2_trans_glops = {
.go_xmote_th = trans_go_xmote_th,
.go_xmote_bh = trans_go_xmote_bh,
.go_drop_th = trans_go_drop_th,
.go_type = LM_TYPE_NONDISK,
};
const struct gfs2_glock_operations gfs2_iopen_glops = {
.go_type = LM_TYPE_IOPEN,
};
const struct gfs2_glock_operations gfs2_flock_glops = {
.go_type = LM_TYPE_FLOCK,
};
const struct gfs2_glock_operations gfs2_nondisk_glops = {
.go_type = LM_TYPE_NONDISK,
};
const struct gfs2_glock_operations gfs2_quota_glops = {
.go_demote_ok = quota_go_demote_ok,
.go_type = LM_TYPE_QUOTA,
};
const struct gfs2_glock_operations gfs2_journal_glops = {
.go_type = LM_TYPE_JOURNAL,
};