linux/fs/gfs2/glops.c
Steven Whitehouse 846f404552 GFS2: Don't flush delete workqueue when releasing the transaction lock
There is no requirement to flush the delete workqueue before a
gfs2 filesystem is suspended. The workqueue's work will just
be suspended along with the rest of the tasks on the filesystem.

The resolves a deadlock situation where the transaction lock's
demotion code was trying to flush the delete workqueue while at
the same time, the workqueue was waiting for the transaction
lock.

The delete workqueue is flushed by gfs2_make_fs_ro() already, so
that umount/remount are correctly protected anyway.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2010-12-16 15:18:48 +00:00

460 lines
11 KiB
C

/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2008 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/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/gfs2_ondisk.h>
#include <linux/bio.h>
#include <linux/posix_acl.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;
struct list_head *head = &gl->gl_ail_list;
struct gfs2_bufdata *bd;
struct buffer_head *bh;
struct gfs2_trans tr;
memset(&tr, 0, sizeof(tr));
tr.tr_revokes = atomic_read(&gl->gl_ail_count);
if (!tr.tr_revokes)
return;
/* A shortened, inline version of gfs2_trans_begin() */
tr.tr_reserved = 1 + gfs2_struct2blk(sdp, tr.tr_revokes, sizeof(u64));
tr.tr_ip = (unsigned long)__builtin_return_address(0);
INIT_LIST_HEAD(&tr.tr_list_buf);
gfs2_log_reserve(sdp, tr.tr_reserved);
BUG_ON(current->journal_info);
current->journal_info = &tr;
gfs2_log_lock(sdp);
while (!list_empty(head)) {
bd = list_entry(head->next, struct gfs2_bufdata,
bd_ail_gl_list);
bh = bd->bd_bh;
gfs2_remove_from_ail(bd);
bd->bd_bh = NULL;
bh->b_private = NULL;
bd->bd_blkno = bh->b_blocknr;
gfs2_assert_withdraw(sdp, !buffer_busy(bh));
gfs2_trans_add_revoke(sdp, bd);
}
gfs2_assert_withdraw(sdp, !atomic_read(&gl->gl_ail_count));
gfs2_log_unlock(sdp);
gfs2_trans_end(sdp);
gfs2_log_flush(sdp, NULL);
}
/**
* rgrp_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 rgrp_go_sync(struct gfs2_glock *gl)
{
struct address_space *metamapping = gfs2_glock2aspace(gl);
int error;
if (!test_and_clear_bit(GLF_DIRTY, &gl->gl_flags))
return;
BUG_ON(gl->gl_state != LM_ST_EXCLUSIVE);
gfs2_log_flush(gl->gl_sbd, gl);
filemap_fdatawrite(metamapping);
error = filemap_fdatawait(metamapping);
mapping_set_error(metamapping, error);
gfs2_ail_empty_gl(gl);
}
/**
* rgrp_go_inval - invalidate the metadata for this glock
* @gl: the glock
* @flags:
*
* We never used LM_ST_DEFERRED with resource groups, so that we
* should always see the metadata flag set here.
*
*/
static void rgrp_go_inval(struct gfs2_glock *gl, int flags)
{
struct address_space *mapping = gfs2_glock2aspace(gl);
BUG_ON(!(flags & DIO_METADATA));
gfs2_assert_withdraw(gl->gl_sbd, !atomic_read(&gl->gl_ail_count));
truncate_inode_pages(mapping, 0);
if (gl->gl_object) {
struct gfs2_rgrpd *rgd = (struct gfs2_rgrpd *)gl->gl_object;
rgd->rd_flags &= ~GFS2_RDF_UPTODATE;
}
}
/**
* 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;
struct address_space *metamapping = gfs2_glock2aspace(gl);
int error;
if (ip && !S_ISREG(ip->i_inode.i_mode))
ip = NULL;
if (ip && test_and_clear_bit(GIF_SW_PAGED, &ip->i_flags))
unmap_shared_mapping_range(ip->i_inode.i_mapping, 0, 0);
if (!test_and_clear_bit(GLF_DIRTY, &gl->gl_flags))
return;
BUG_ON(gl->gl_state != LM_ST_EXCLUSIVE);
gfs2_log_flush(gl->gl_sbd, gl);
filemap_fdatawrite(metamapping);
if (ip) {
struct address_space *mapping = ip->i_inode.i_mapping;
filemap_fdatawrite(mapping);
error = filemap_fdatawait(mapping);
mapping_set_error(mapping, error);
}
error = filemap_fdatawait(metamapping);
mapping_set_error(metamapping, error);
gfs2_ail_empty_gl(gl);
/*
* Writeback of the data mapping may cause the dirty flag to be set
* so we have to clear it again here.
*/
smp_mb__before_clear_bit();
clear_bit(GLF_DIRTY, &gl->gl_flags);
}
/**
* inode_go_inval - prepare a inode glock to be released
* @gl: the glock
* @flags:
*
* Normally we invlidate everything, but if we are moving into
* LM_ST_DEFERRED from LM_ST_SHARED or LM_ST_EXCLUSIVE then we
* can keep hold of the metadata, since it won't have changed.
*
*/
static void inode_go_inval(struct gfs2_glock *gl, int flags)
{
struct gfs2_inode *ip = gl->gl_object;
gfs2_assert_withdraw(gl->gl_sbd, !atomic_read(&gl->gl_ail_count));
if (flags & DIO_METADATA) {
struct address_space *mapping = gfs2_glock2aspace(gl);
truncate_inode_pages(mapping, 0);
if (ip) {
set_bit(GIF_INVALID, &ip->i_flags);
forget_all_cached_acls(&ip->i_inode);
}
}
if (ip == GFS2_I(gl->gl_sbd->sd_rindex))
gl->gl_sbd->sd_rindex_uptodate = 0;
if (ip && S_ISREG(ip->i_inode.i_mode))
truncate_inode_pages(ip->i_inode.i_mapping, 0);
}
/**
* 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(const struct gfs2_glock *gl)
{
struct gfs2_sbd *sdp = gl->gl_sbd;
if (sdp->sd_jindex == gl->gl_object || sdp->sd_rindex == gl->gl_object)
return 0;
return 1;
}
/**
* 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_sbd *sdp = gl->gl_sbd;
struct gfs2_inode *ip = gl->gl_object;
int error = 0;
if (!ip || (gh->gh_flags & GL_SKIP))
return 0;
if (test_bit(GIF_INVALID, &ip->i_flags)) {
error = gfs2_inode_refresh(ip);
if (error)
return error;
}
if ((ip->i_diskflags & GFS2_DIF_TRUNC_IN_PROG) &&
(gl->gl_state == LM_ST_EXCLUSIVE) &&
(gh->gh_state == LM_ST_EXCLUSIVE)) {
spin_lock(&sdp->sd_trunc_lock);
if (list_empty(&ip->i_trunc_list))
list_add(&sdp->sd_trunc_list, &ip->i_trunc_list);
spin_unlock(&sdp->sd_trunc_lock);
wake_up(&sdp->sd_quota_wait);
return 1;
}
return error;
}
/**
* inode_go_dump - print information about an inode
* @seq: The iterator
* @ip: the inode
*
* Returns: 0 on success, -ENOBUFS when we run out of space
*/
static int inode_go_dump(struct seq_file *seq, const struct gfs2_glock *gl)
{
const struct gfs2_inode *ip = gl->gl_object;
if (ip == NULL)
return 0;
gfs2_print_dbg(seq, " I: n:%llu/%llu t:%u f:0x%02lx d:0x%08x s:%llu\n",
(unsigned long long)ip->i_no_formal_ino,
(unsigned long long)ip->i_no_addr,
IF2DT(ip->i_inode.i_mode), ip->i_flags,
(unsigned int)ip->i_diskflags,
(unsigned long long)i_size_read(&ip->i_inode));
return 0;
}
/**
* 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(const struct gfs2_glock *gl)
{
const struct address_space *mapping = (const struct address_space *)(gl + 1);
return !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_sync - promote/demote the transaction glock
* @gl: the glock
* @state: the requested state
* @flags:
*
*/
static void trans_go_sync(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 int trans_go_xmote_bh(struct gfs2_glock *gl, struct gfs2_holder *gh)
{
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 (test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)) {
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);
}
}
return 0;
}
/**
* trans_go_demote_ok
* @gl: the glock
*
* Always returns 0
*/
static int trans_go_demote_ok(const struct gfs2_glock *gl)
{
return 0;
}
/**
* iopen_go_callback - schedule the dcache entry for the inode to be deleted
* @gl: the glock
*
* gl_spin lock is held while calling this
*/
static void iopen_go_callback(struct gfs2_glock *gl)
{
struct gfs2_inode *ip = (struct gfs2_inode *)gl->gl_object;
if (gl->gl_demote_state == LM_ST_UNLOCKED &&
gl->gl_state == LM_ST_SHARED && ip) {
gfs2_glock_hold(gl);
if (queue_work(gfs2_delete_workqueue, &gl->gl_delete) == 0)
gfs2_glock_put_nolock(gl);
}
}
const struct gfs2_glock_operations gfs2_meta_glops = {
.go_type = LM_TYPE_META,
};
const struct gfs2_glock_operations gfs2_inode_glops = {
.go_xmote_th = inode_go_sync,
.go_inval = inode_go_inval,
.go_demote_ok = inode_go_demote_ok,
.go_lock = inode_go_lock,
.go_dump = inode_go_dump,
.go_type = LM_TYPE_INODE,
.go_min_hold_time = HZ / 5,
.go_flags = GLOF_ASPACE,
};
const struct gfs2_glock_operations gfs2_rgrp_glops = {
.go_xmote_th = rgrp_go_sync,
.go_inval = rgrp_go_inval,
.go_demote_ok = rgrp_go_demote_ok,
.go_lock = rgrp_go_lock,
.go_unlock = rgrp_go_unlock,
.go_dump = gfs2_rgrp_dump,
.go_type = LM_TYPE_RGRP,
.go_min_hold_time = HZ / 5,
.go_flags = GLOF_ASPACE,
};
const struct gfs2_glock_operations gfs2_trans_glops = {
.go_xmote_th = trans_go_sync,
.go_xmote_bh = trans_go_xmote_bh,
.go_demote_ok = trans_go_demote_ok,
.go_type = LM_TYPE_NONDISK,
};
const struct gfs2_glock_operations gfs2_iopen_glops = {
.go_type = LM_TYPE_IOPEN,
.go_callback = iopen_go_callback,
};
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_type = LM_TYPE_QUOTA,
};
const struct gfs2_glock_operations gfs2_journal_glops = {
.go_type = LM_TYPE_JOURNAL,
};
const struct gfs2_glock_operations *gfs2_glops_list[] = {
[LM_TYPE_META] = &gfs2_meta_glops,
[LM_TYPE_INODE] = &gfs2_inode_glops,
[LM_TYPE_RGRP] = &gfs2_rgrp_glops,
[LM_TYPE_IOPEN] = &gfs2_iopen_glops,
[LM_TYPE_FLOCK] = &gfs2_flock_glops,
[LM_TYPE_NONDISK] = &gfs2_nondisk_glops,
[LM_TYPE_QUOTA] = &gfs2_quota_glops,
[LM_TYPE_JOURNAL] = &gfs2_journal_glops,
};