WSL2-Linux-Kernel/fs/gfs2/super.c

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40 KiB
C
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/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2007 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.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/bio.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/statfs.h>
#include <linux/seq_file.h>
#include <linux/mount.h>
#include <linux/kthread.h>
#include <linux/delay.h>
#include <linux/gfs2_ondisk.h>
#include <linux/crc32.h>
#include <linux/time.h>
#include <linux/wait.h>
#include <linux/writeback.h>
#include <linux/backing-dev.h>
#include <linux/kernel.h>
#include "gfs2.h"
#include "incore.h"
#include "bmap.h"
#include "dir.h"
#include "glock.h"
#include "glops.h"
#include "inode.h"
#include "log.h"
#include "meta_io.h"
#include "quota.h"
#include "recovery.h"
#include "rgrp.h"
#include "super.h"
#include "trans.h"
#include "util.h"
#include "sys.h"
#include "xattr.h"
#define args_neq(a1, a2, x) ((a1)->ar_##x != (a2)->ar_##x)
enum {
Opt_lockproto,
Opt_locktable,
Opt_hostdata,
Opt_spectator,
Opt_ignore_local_fs,
Opt_localflocks,
Opt_localcaching,
Opt_debug,
Opt_nodebug,
Opt_upgrade,
Opt_acl,
Opt_noacl,
Opt_quota_off,
Opt_quota_account,
Opt_quota_on,
Opt_quota,
Opt_noquota,
Opt_suiddir,
Opt_nosuiddir,
Opt_data_writeback,
Opt_data_ordered,
Opt_meta,
Opt_discard,
Opt_nodiscard,
Opt_commit,
Opt_err_withdraw,
Opt_err_panic,
Opt_statfs_quantum,
Opt_statfs_percent,
Opt_quota_quantum,
Opt_barrier,
Opt_nobarrier,
Opt_rgrplvb,
Opt_norgrplvb,
Opt_error,
};
static const match_table_t tokens = {
{Opt_lockproto, "lockproto=%s"},
{Opt_locktable, "locktable=%s"},
{Opt_hostdata, "hostdata=%s"},
{Opt_spectator, "spectator"},
{Opt_spectator, "norecovery"},
{Opt_ignore_local_fs, "ignore_local_fs"},
{Opt_localflocks, "localflocks"},
{Opt_localcaching, "localcaching"},
{Opt_debug, "debug"},
{Opt_nodebug, "nodebug"},
{Opt_upgrade, "upgrade"},
{Opt_acl, "acl"},
{Opt_noacl, "noacl"},
{Opt_quota_off, "quota=off"},
{Opt_quota_account, "quota=account"},
{Opt_quota_on, "quota=on"},
{Opt_quota, "quota"},
{Opt_noquota, "noquota"},
{Opt_suiddir, "suiddir"},
{Opt_nosuiddir, "nosuiddir"},
{Opt_data_writeback, "data=writeback"},
{Opt_data_ordered, "data=ordered"},
{Opt_meta, "meta"},
{Opt_discard, "discard"},
{Opt_nodiscard, "nodiscard"},
{Opt_commit, "commit=%d"},
{Opt_err_withdraw, "errors=withdraw"},
{Opt_err_panic, "errors=panic"},
{Opt_statfs_quantum, "statfs_quantum=%d"},
{Opt_statfs_percent, "statfs_percent=%d"},
{Opt_quota_quantum, "quota_quantum=%d"},
{Opt_barrier, "barrier"},
{Opt_nobarrier, "nobarrier"},
{Opt_rgrplvb, "rgrplvb"},
{Opt_norgrplvb, "norgrplvb"},
{Opt_error, NULL}
};
/**
* gfs2_mount_args - Parse mount options
* @args: The structure into which the parsed options will be written
* @options: The options to parse
*
* Return: errno
*/
int gfs2_mount_args(struct gfs2_args *args, char *options)
{
char *o;
int token;
substring_t tmp[MAX_OPT_ARGS];
int rv;
/* Split the options into tokens with the "," character and
process them */
while (1) {
o = strsep(&options, ",");
if (o == NULL)
break;
if (*o == '\0')
continue;
token = match_token(o, tokens, tmp);
switch (token) {
case Opt_lockproto:
match_strlcpy(args->ar_lockproto, &tmp[0],
GFS2_LOCKNAME_LEN);
break;
case Opt_locktable:
match_strlcpy(args->ar_locktable, &tmp[0],
GFS2_LOCKNAME_LEN);
break;
case Opt_hostdata:
match_strlcpy(args->ar_hostdata, &tmp[0],
GFS2_LOCKNAME_LEN);
break;
case Opt_spectator:
args->ar_spectator = 1;
break;
case Opt_ignore_local_fs:
/* Retained for backwards compat only */
break;
case Opt_localflocks:
args->ar_localflocks = 1;
break;
case Opt_localcaching:
/* Retained for backwards compat only */
break;
case Opt_debug:
if (args->ar_errors == GFS2_ERRORS_PANIC) {
pr_warn("-o debug and -o errors=panic are mutually exclusive\n");
return -EINVAL;
}
args->ar_debug = 1;
break;
case Opt_nodebug:
args->ar_debug = 0;
break;
case Opt_upgrade:
/* Retained for backwards compat only */
break;
case Opt_acl:
args->ar_posix_acl = 1;
break;
case Opt_noacl:
args->ar_posix_acl = 0;
break;
case Opt_quota_off:
case Opt_noquota:
args->ar_quota = GFS2_QUOTA_OFF;
break;
case Opt_quota_account:
args->ar_quota = GFS2_QUOTA_ACCOUNT;
break;
case Opt_quota_on:
case Opt_quota:
args->ar_quota = GFS2_QUOTA_ON;
break;
case Opt_suiddir:
args->ar_suiddir = 1;
break;
case Opt_nosuiddir:
args->ar_suiddir = 0;
break;
case Opt_data_writeback:
args->ar_data = GFS2_DATA_WRITEBACK;
break;
case Opt_data_ordered:
args->ar_data = GFS2_DATA_ORDERED;
break;
case Opt_meta:
args->ar_meta = 1;
break;
case Opt_discard:
args->ar_discard = 1;
break;
case Opt_nodiscard:
args->ar_discard = 0;
break;
case Opt_commit:
rv = match_int(&tmp[0], &args->ar_commit);
if (rv || args->ar_commit <= 0) {
pr_warn("commit mount option requires a positive numeric argument\n");
return rv ? rv : -EINVAL;
}
break;
case Opt_statfs_quantum:
rv = match_int(&tmp[0], &args->ar_statfs_quantum);
if (rv || args->ar_statfs_quantum < 0) {
pr_warn("statfs_quantum mount option requires a non-negative numeric argument\n");
return rv ? rv : -EINVAL;
}
break;
case Opt_quota_quantum:
rv = match_int(&tmp[0], &args->ar_quota_quantum);
if (rv || args->ar_quota_quantum <= 0) {
pr_warn("quota_quantum mount option requires a positive numeric argument\n");
return rv ? rv : -EINVAL;
}
break;
case Opt_statfs_percent:
rv = match_int(&tmp[0], &args->ar_statfs_percent);
if (rv || args->ar_statfs_percent < 0 ||
args->ar_statfs_percent > 100) {
pr_warn("statfs_percent mount option requires a numeric argument between 0 and 100\n");
return rv ? rv : -EINVAL;
}
break;
case Opt_err_withdraw:
args->ar_errors = GFS2_ERRORS_WITHDRAW;
break;
case Opt_err_panic:
if (args->ar_debug) {
pr_warn("-o debug and -o errors=panic are mutually exclusive\n");
return -EINVAL;
}
args->ar_errors = GFS2_ERRORS_PANIC;
break;
case Opt_barrier:
args->ar_nobarrier = 0;
break;
case Opt_nobarrier:
args->ar_nobarrier = 1;
break;
case Opt_rgrplvb:
args->ar_rgrplvb = 1;
break;
case Opt_norgrplvb:
args->ar_rgrplvb = 0;
break;
case Opt_error:
default:
pr_warn("invalid mount option: %s\n", o);
return -EINVAL;
}
}
return 0;
}
/**
* gfs2_jindex_free - Clear all the journal index information
* @sdp: The GFS2 superblock
*
*/
void gfs2_jindex_free(struct gfs2_sbd *sdp)
{
struct list_head list;
struct gfs2_jdesc *jd;
spin_lock(&sdp->sd_jindex_spin);
list_add(&list, &sdp->sd_jindex_list);
list_del_init(&sdp->sd_jindex_list);
sdp->sd_journals = 0;
spin_unlock(&sdp->sd_jindex_spin);
while (!list_empty(&list)) {
jd = list_entry(list.next, struct gfs2_jdesc, jd_list);
gfs2_free_journal_extents(jd);
list_del(&jd->jd_list);
iput(jd->jd_inode);
kfree(jd);
}
}
static struct gfs2_jdesc *jdesc_find_i(struct list_head *head, unsigned int jid)
{
struct gfs2_jdesc *jd;
int found = 0;
list_for_each_entry(jd, head, jd_list) {
if (jd->jd_jid == jid) {
found = 1;
break;
}
}
if (!found)
jd = NULL;
return jd;
}
struct gfs2_jdesc *gfs2_jdesc_find(struct gfs2_sbd *sdp, unsigned int jid)
{
struct gfs2_jdesc *jd;
spin_lock(&sdp->sd_jindex_spin);
jd = jdesc_find_i(&sdp->sd_jindex_list, jid);
spin_unlock(&sdp->sd_jindex_spin);
return jd;
}
int gfs2_jdesc_check(struct gfs2_jdesc *jd)
{
struct gfs2_inode *ip = GFS2_I(jd->jd_inode);
struct gfs2_sbd *sdp = GFS2_SB(jd->jd_inode);
u64 size = i_size_read(jd->jd_inode);
if (gfs2_check_internal_file_size(jd->jd_inode, 8 << 20, 1 << 30))
return -EIO;
jd->jd_blocks = size >> sdp->sd_sb.sb_bsize_shift;
if (gfs2_write_alloc_required(ip, 0, size)) {
gfs2_consist_inode(ip);
return -EIO;
}
return 0;
}
static int init_threads(struct gfs2_sbd *sdp)
{
struct task_struct *p;
int error = 0;
p = kthread_run(gfs2_logd, sdp, "gfs2_logd");
if (IS_ERR(p)) {
error = PTR_ERR(p);
fs_err(sdp, "can't start logd thread: %d\n", error);
return error;
}
sdp->sd_logd_process = p;
p = kthread_run(gfs2_quotad, sdp, "gfs2_quotad");
if (IS_ERR(p)) {
error = PTR_ERR(p);
fs_err(sdp, "can't start quotad thread: %d\n", error);
goto fail;
}
sdp->sd_quotad_process = p;
return 0;
fail:
kthread_stop(sdp->sd_logd_process);
return error;
}
/**
* gfs2_make_fs_rw - Turn a Read-Only FS into a Read-Write one
* @sdp: the filesystem
*
* Returns: errno
*/
int gfs2_make_fs_rw(struct gfs2_sbd *sdp)
{
struct gfs2_inode *ip = GFS2_I(sdp->sd_jdesc->jd_inode);
struct gfs2_glock *j_gl = ip->i_gl;
struct gfs2_holder freeze_gh;
struct gfs2_log_header_host head;
int error;
error = init_threads(sdp);
if (error)
return error;
GFS2: remove transaction glock GFS2 has a transaction glock, which must be grabbed for every transaction, whose purpose is to deal with freezing the filesystem. Aside from this involving a large amount of locking, it is very easy to make the current fsfreeze code hang on unfreezing. This patch rewrites how gfs2 handles freezing the filesystem. The transaction glock is removed. In it's place is a freeze glock, which is cached (but not held) in a shared state by every node in the cluster when the filesystem is mounted. This lock only needs to be grabbed on freezing, and actions which need to be safe from freezing, like recovery. When a node wants to freeze the filesystem, it grabs this glock exclusively. When the freeze glock state changes on the nodes (either from shared to unlocked, or shared to exclusive), the filesystem does a special log flush. gfs2_log_flush() does all the work for flushing out the and shutting down the incore log, and then it tries to grab the freeze glock in a shared state again. Since the filesystem is stuck in gfs2_log_flush, no new transaction can start, and nothing can be written to disk. Unfreezing the filesytem simply involes dropping the freeze glock, allowing gfs2_log_flush() to grab and then release the shared lock, so it is cached for next time. However, in order for the unfreezing ioctl to occur, gfs2 needs to get a shared lock on the filesystem root directory inode to check permissions. If that glock has already been grabbed exclusively, fsfreeze will be unable to get the shared lock and unfreeze the filesystem. In order to allow the unfreeze, this patch makes gfs2 grab a shared lock on the filesystem root directory during the freeze, and hold it until it unfreezes the filesystem. The functions which need to grab a shared lock in order to allow the unfreeze ioctl to be issued now use the lock grabbed by the freeze code instead. The freeze and unfreeze code take care to make sure that this shared lock will not be dropped while another process is using it. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-05-02 07:26:55 +04:00
error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, 0,
&freeze_gh);
if (error)
goto fail_threads;
j_gl->gl_ops->go_inval(j_gl, DIO_METADATA);
error = gfs2_find_jhead(sdp->sd_jdesc, &head);
if (error)
goto fail;
if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
gfs2_consist(sdp);
error = -EIO;
goto fail;
}
/* Initialize some head of the log stuff */
sdp->sd_log_sequence = head.lh_sequence + 1;
gfs2_log_pointers_init(sdp, head.lh_blkno);
error = gfs2_quota_init(sdp);
if (error)
goto fail;
set_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
gfs2_glock_dq_uninit(&freeze_gh);
return 0;
fail:
freeze_gh.gh_flags |= GL_NOCACHE;
gfs2_glock_dq_uninit(&freeze_gh);
fail_threads:
kthread_stop(sdp->sd_quotad_process);
kthread_stop(sdp->sd_logd_process);
return error;
}
void gfs2_statfs_change_in(struct gfs2_statfs_change_host *sc, const void *buf)
{
const struct gfs2_statfs_change *str = buf;
sc->sc_total = be64_to_cpu(str->sc_total);
sc->sc_free = be64_to_cpu(str->sc_free);
sc->sc_dinodes = be64_to_cpu(str->sc_dinodes);
}
static void gfs2_statfs_change_out(const struct gfs2_statfs_change_host *sc, void *buf)
{
struct gfs2_statfs_change *str = buf;
str->sc_total = cpu_to_be64(sc->sc_total);
str->sc_free = cpu_to_be64(sc->sc_free);
str->sc_dinodes = cpu_to_be64(sc->sc_dinodes);
}
int gfs2_statfs_init(struct gfs2_sbd *sdp)
{
struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
struct buffer_head *m_bh, *l_bh;
struct gfs2_holder gh;
int error;
error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
&gh);
if (error)
return error;
error = gfs2_meta_inode_buffer(m_ip, &m_bh);
if (error)
goto out;
if (sdp->sd_args.ar_spectator) {
spin_lock(&sdp->sd_statfs_spin);
gfs2_statfs_change_in(m_sc, m_bh->b_data +
sizeof(struct gfs2_dinode));
spin_unlock(&sdp->sd_statfs_spin);
} else {
error = gfs2_meta_inode_buffer(l_ip, &l_bh);
if (error)
goto out_m_bh;
spin_lock(&sdp->sd_statfs_spin);
gfs2_statfs_change_in(m_sc, m_bh->b_data +
sizeof(struct gfs2_dinode));
gfs2_statfs_change_in(l_sc, l_bh->b_data +
sizeof(struct gfs2_dinode));
spin_unlock(&sdp->sd_statfs_spin);
brelse(l_bh);
}
out_m_bh:
brelse(m_bh);
out:
gfs2_glock_dq_uninit(&gh);
return 0;
}
void gfs2_statfs_change(struct gfs2_sbd *sdp, s64 total, s64 free,
s64 dinodes)
{
struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
struct buffer_head *l_bh;
s64 x, y;
int need_sync = 0;
int error;
error = gfs2_meta_inode_buffer(l_ip, &l_bh);
if (error)
return;
gfs2_trans_add_meta(l_ip->i_gl, l_bh);
spin_lock(&sdp->sd_statfs_spin);
l_sc->sc_total += total;
l_sc->sc_free += free;
l_sc->sc_dinodes += dinodes;
gfs2_statfs_change_out(l_sc, l_bh->b_data + sizeof(struct gfs2_dinode));
if (sdp->sd_args.ar_statfs_percent) {
x = 100 * l_sc->sc_free;
y = m_sc->sc_free * sdp->sd_args.ar_statfs_percent;
if (x >= y || x <= -y)
need_sync = 1;
}
spin_unlock(&sdp->sd_statfs_spin);
brelse(l_bh);
if (need_sync)
gfs2_wake_up_statfs(sdp);
}
void update_statfs(struct gfs2_sbd *sdp, struct buffer_head *m_bh,
struct buffer_head *l_bh)
{
struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
gfs2_trans_add_meta(l_ip->i_gl, l_bh);
spin_lock(&sdp->sd_statfs_spin);
m_sc->sc_total += l_sc->sc_total;
m_sc->sc_free += l_sc->sc_free;
m_sc->sc_dinodes += l_sc->sc_dinodes;
memset(l_sc, 0, sizeof(struct gfs2_statfs_change));
memset(l_bh->b_data + sizeof(struct gfs2_dinode),
0, sizeof(struct gfs2_statfs_change));
spin_unlock(&sdp->sd_statfs_spin);
gfs2_trans_add_meta(m_ip->i_gl, m_bh);
gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
}
int gfs2_statfs_sync(struct super_block *sb, int type)
{
struct gfs2_sbd *sdp = sb->s_fs_info;
struct gfs2_inode *m_ip = GFS2_I(sdp->sd_statfs_inode);
struct gfs2_inode *l_ip = GFS2_I(sdp->sd_sc_inode);
struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
struct gfs2_holder gh;
struct buffer_head *m_bh, *l_bh;
int error;
sb_start_write(sb);
error = gfs2_glock_nq_init(m_ip->i_gl, LM_ST_EXCLUSIVE, GL_NOCACHE,
&gh);
if (error)
goto out;
error = gfs2_meta_inode_buffer(m_ip, &m_bh);
if (error)
goto out_unlock;
spin_lock(&sdp->sd_statfs_spin);
gfs2_statfs_change_in(m_sc, m_bh->b_data +
sizeof(struct gfs2_dinode));
if (!l_sc->sc_total && !l_sc->sc_free && !l_sc->sc_dinodes) {
spin_unlock(&sdp->sd_statfs_spin);
goto out_bh;
}
spin_unlock(&sdp->sd_statfs_spin);
error = gfs2_meta_inode_buffer(l_ip, &l_bh);
if (error)
goto out_bh;
error = gfs2_trans_begin(sdp, 2 * RES_DINODE, 0);
if (error)
goto out_bh2;
update_statfs(sdp, m_bh, l_bh);
sdp->sd_statfs_force_sync = 0;
gfs2_trans_end(sdp);
out_bh2:
brelse(l_bh);
out_bh:
brelse(m_bh);
out_unlock:
gfs2_glock_dq_uninit(&gh);
out:
sb_end_write(sb);
return error;
}
struct lfcc {
struct list_head list;
struct gfs2_holder gh;
};
/**
* gfs2_lock_fs_check_clean - Stop all writes to the FS and check that all
* journals are clean
* @sdp: the file system
* @state: the state to put the transaction lock into
* @t_gh: the hold on the transaction lock
*
* Returns: errno
*/
static int gfs2_lock_fs_check_clean(struct gfs2_sbd *sdp,
GFS2: remove transaction glock GFS2 has a transaction glock, which must be grabbed for every transaction, whose purpose is to deal with freezing the filesystem. Aside from this involving a large amount of locking, it is very easy to make the current fsfreeze code hang on unfreezing. This patch rewrites how gfs2 handles freezing the filesystem. The transaction glock is removed. In it's place is a freeze glock, which is cached (but not held) in a shared state by every node in the cluster when the filesystem is mounted. This lock only needs to be grabbed on freezing, and actions which need to be safe from freezing, like recovery. When a node wants to freeze the filesystem, it grabs this glock exclusively. When the freeze glock state changes on the nodes (either from shared to unlocked, or shared to exclusive), the filesystem does a special log flush. gfs2_log_flush() does all the work for flushing out the and shutting down the incore log, and then it tries to grab the freeze glock in a shared state again. Since the filesystem is stuck in gfs2_log_flush, no new transaction can start, and nothing can be written to disk. Unfreezing the filesytem simply involes dropping the freeze glock, allowing gfs2_log_flush() to grab and then release the shared lock, so it is cached for next time. However, in order for the unfreezing ioctl to occur, gfs2 needs to get a shared lock on the filesystem root directory inode to check permissions. If that glock has already been grabbed exclusively, fsfreeze will be unable to get the shared lock and unfreeze the filesystem. In order to allow the unfreeze, this patch makes gfs2 grab a shared lock on the filesystem root directory during the freeze, and hold it until it unfreezes the filesystem. The functions which need to grab a shared lock in order to allow the unfreeze ioctl to be issued now use the lock grabbed by the freeze code instead. The freeze and unfreeze code take care to make sure that this shared lock will not be dropped while another process is using it. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-05-02 07:26:55 +04:00
struct gfs2_holder *freeze_gh)
{
struct gfs2_inode *ip;
struct gfs2_jdesc *jd;
struct lfcc *lfcc;
LIST_HEAD(list);
struct gfs2_log_header_host lh;
int error;
list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
lfcc = kmalloc(sizeof(struct lfcc), GFP_KERNEL);
if (!lfcc) {
error = -ENOMEM;
goto out;
}
ip = GFS2_I(jd->jd_inode);
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, 0, &lfcc->gh);
if (error) {
kfree(lfcc);
goto out;
}
list_add(&lfcc->list, &list);
}
GFS2: remove transaction glock GFS2 has a transaction glock, which must be grabbed for every transaction, whose purpose is to deal with freezing the filesystem. Aside from this involving a large amount of locking, it is very easy to make the current fsfreeze code hang on unfreezing. This patch rewrites how gfs2 handles freezing the filesystem. The transaction glock is removed. In it's place is a freeze glock, which is cached (but not held) in a shared state by every node in the cluster when the filesystem is mounted. This lock only needs to be grabbed on freezing, and actions which need to be safe from freezing, like recovery. When a node wants to freeze the filesystem, it grabs this glock exclusively. When the freeze glock state changes on the nodes (either from shared to unlocked, or shared to exclusive), the filesystem does a special log flush. gfs2_log_flush() does all the work for flushing out the and shutting down the incore log, and then it tries to grab the freeze glock in a shared state again. Since the filesystem is stuck in gfs2_log_flush, no new transaction can start, and nothing can be written to disk. Unfreezing the filesytem simply involes dropping the freeze glock, allowing gfs2_log_flush() to grab and then release the shared lock, so it is cached for next time. However, in order for the unfreezing ioctl to occur, gfs2 needs to get a shared lock on the filesystem root directory inode to check permissions. If that glock has already been grabbed exclusively, fsfreeze will be unable to get the shared lock and unfreeze the filesystem. In order to allow the unfreeze, this patch makes gfs2 grab a shared lock on the filesystem root directory during the freeze, and hold it until it unfreezes the filesystem. The functions which need to grab a shared lock in order to allow the unfreeze ioctl to be issued now use the lock grabbed by the freeze code instead. The freeze and unfreeze code take care to make sure that this shared lock will not be dropped while another process is using it. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-05-02 07:26:55 +04:00
error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_EXCLUSIVE,
GL_NOCACHE, freeze_gh);
list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
error = gfs2_jdesc_check(jd);
if (error)
break;
error = gfs2_find_jhead(jd, &lh);
if (error)
break;
if (!(lh.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
error = -EBUSY;
break;
}
}
if (error)
GFS2: remove transaction glock GFS2 has a transaction glock, which must be grabbed for every transaction, whose purpose is to deal with freezing the filesystem. Aside from this involving a large amount of locking, it is very easy to make the current fsfreeze code hang on unfreezing. This patch rewrites how gfs2 handles freezing the filesystem. The transaction glock is removed. In it's place is a freeze glock, which is cached (but not held) in a shared state by every node in the cluster when the filesystem is mounted. This lock only needs to be grabbed on freezing, and actions which need to be safe from freezing, like recovery. When a node wants to freeze the filesystem, it grabs this glock exclusively. When the freeze glock state changes on the nodes (either from shared to unlocked, or shared to exclusive), the filesystem does a special log flush. gfs2_log_flush() does all the work for flushing out the and shutting down the incore log, and then it tries to grab the freeze glock in a shared state again. Since the filesystem is stuck in gfs2_log_flush, no new transaction can start, and nothing can be written to disk. Unfreezing the filesytem simply involes dropping the freeze glock, allowing gfs2_log_flush() to grab and then release the shared lock, so it is cached for next time. However, in order for the unfreezing ioctl to occur, gfs2 needs to get a shared lock on the filesystem root directory inode to check permissions. If that glock has already been grabbed exclusively, fsfreeze will be unable to get the shared lock and unfreeze the filesystem. In order to allow the unfreeze, this patch makes gfs2 grab a shared lock on the filesystem root directory during the freeze, and hold it until it unfreezes the filesystem. The functions which need to grab a shared lock in order to allow the unfreeze ioctl to be issued now use the lock grabbed by the freeze code instead. The freeze and unfreeze code take care to make sure that this shared lock will not be dropped while another process is using it. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-05-02 07:26:55 +04:00
gfs2_glock_dq_uninit(freeze_gh);
out:
while (!list_empty(&list)) {
lfcc = list_entry(list.next, struct lfcc, list);
list_del(&lfcc->list);
gfs2_glock_dq_uninit(&lfcc->gh);
kfree(lfcc);
}
return error;
}
void gfs2_dinode_out(const struct gfs2_inode *ip, void *buf)
{
struct gfs2_dinode *str = buf;
str->di_header.mh_magic = cpu_to_be32(GFS2_MAGIC);
str->di_header.mh_type = cpu_to_be32(GFS2_METATYPE_DI);
str->di_header.mh_format = cpu_to_be32(GFS2_FORMAT_DI);
str->di_num.no_addr = cpu_to_be64(ip->i_no_addr);
str->di_num.no_formal_ino = cpu_to_be64(ip->i_no_formal_ino);
str->di_mode = cpu_to_be32(ip->i_inode.i_mode);
str->di_uid = cpu_to_be32(i_uid_read(&ip->i_inode));
str->di_gid = cpu_to_be32(i_gid_read(&ip->i_inode));
str->di_nlink = cpu_to_be32(ip->i_inode.i_nlink);
str->di_size = cpu_to_be64(i_size_read(&ip->i_inode));
str->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode));
str->di_atime = cpu_to_be64(ip->i_inode.i_atime.tv_sec);
str->di_mtime = cpu_to_be64(ip->i_inode.i_mtime.tv_sec);
str->di_ctime = cpu_to_be64(ip->i_inode.i_ctime.tv_sec);
str->di_goal_meta = cpu_to_be64(ip->i_goal);
str->di_goal_data = cpu_to_be64(ip->i_goal);
str->di_generation = cpu_to_be64(ip->i_generation);
str->di_flags = cpu_to_be32(ip->i_diskflags);
str->di_height = cpu_to_be16(ip->i_height);
str->di_payload_format = cpu_to_be32(S_ISDIR(ip->i_inode.i_mode) &&
!(ip->i_diskflags & GFS2_DIF_EXHASH) ?
GFS2_FORMAT_DE : 0);
str->di_depth = cpu_to_be16(ip->i_depth);
str->di_entries = cpu_to_be32(ip->i_entries);
str->di_eattr = cpu_to_be64(ip->i_eattr);
str->di_atime_nsec = cpu_to_be32(ip->i_inode.i_atime.tv_nsec);
str->di_mtime_nsec = cpu_to_be32(ip->i_inode.i_mtime.tv_nsec);
str->di_ctime_nsec = cpu_to_be32(ip->i_inode.i_ctime.tv_nsec);
}
/**
* gfs2_write_inode - Make sure the inode is stable on the disk
* @inode: The inode
* @wbc: The writeback control structure
*
* Returns: errno
*/
static int gfs2_write_inode(struct inode *inode, struct writeback_control *wbc)
{
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_sbd *sdp = GFS2_SB(inode);
struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
struct backing_dev_info *bdi = inode_to_bdi(metamapping->host);
int ret = 0;
if (wbc->sync_mode == WB_SYNC_ALL)
GFS2: remove transaction glock GFS2 has a transaction glock, which must be grabbed for every transaction, whose purpose is to deal with freezing the filesystem. Aside from this involving a large amount of locking, it is very easy to make the current fsfreeze code hang on unfreezing. This patch rewrites how gfs2 handles freezing the filesystem. The transaction glock is removed. In it's place is a freeze glock, which is cached (but not held) in a shared state by every node in the cluster when the filesystem is mounted. This lock only needs to be grabbed on freezing, and actions which need to be safe from freezing, like recovery. When a node wants to freeze the filesystem, it grabs this glock exclusively. When the freeze glock state changes on the nodes (either from shared to unlocked, or shared to exclusive), the filesystem does a special log flush. gfs2_log_flush() does all the work for flushing out the and shutting down the incore log, and then it tries to grab the freeze glock in a shared state again. Since the filesystem is stuck in gfs2_log_flush, no new transaction can start, and nothing can be written to disk. Unfreezing the filesytem simply involes dropping the freeze glock, allowing gfs2_log_flush() to grab and then release the shared lock, so it is cached for next time. However, in order for the unfreezing ioctl to occur, gfs2 needs to get a shared lock on the filesystem root directory inode to check permissions. If that glock has already been grabbed exclusively, fsfreeze will be unable to get the shared lock and unfreeze the filesystem. In order to allow the unfreeze, this patch makes gfs2 grab a shared lock on the filesystem root directory during the freeze, and hold it until it unfreezes the filesystem. The functions which need to grab a shared lock in order to allow the unfreeze ioctl to be issued now use the lock grabbed by the freeze code instead. The freeze and unfreeze code take care to make sure that this shared lock will not be dropped while another process is using it. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-05-02 07:26:55 +04:00
gfs2_log_flush(GFS2_SB(inode), ip->i_gl, NORMAL_FLUSH);
if (bdi->dirty_exceeded)
gfs2_ail1_flush(sdp, wbc);
else
filemap_fdatawrite(metamapping);
if (wbc->sync_mode == WB_SYNC_ALL)
ret = filemap_fdatawait(metamapping);
if (ret)
mark_inode_dirty_sync(inode);
return ret;
}
/**
* gfs2_dirty_inode - check for atime updates
* @inode: The inode in question
* @flags: The type of dirty
*
* Unfortunately it can be called under any combination of inode
* glock and transaction lock, so we have to check carefully.
*
* At the moment this deals only with atime - it should be possible
* to expand that role in future, once a review of the locking has
* been carried out.
*/
static void gfs2_dirty_inode(struct inode *inode, int flags)
{
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_sbd *sdp = GFS2_SB(inode);
struct buffer_head *bh;
struct gfs2_holder gh;
int need_unlock = 0;
int need_endtrans = 0;
int ret;
if (!(flags & (I_DIRTY_DATASYNC|I_DIRTY_SYNC)))
return;
if (!gfs2_glock_is_locked_by_me(ip->i_gl)) {
ret = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh);
if (ret) {
fs_err(sdp, "dirty_inode: glock %d\n", ret);
return;
}
need_unlock = 1;
} else if (WARN_ON_ONCE(ip->i_gl->gl_state != LM_ST_EXCLUSIVE))
return;
if (current->journal_info == NULL) {
ret = gfs2_trans_begin(sdp, RES_DINODE, 0);
if (ret) {
fs_err(sdp, "dirty_inode: gfs2_trans_begin %d\n", ret);
goto out;
}
need_endtrans = 1;
}
ret = gfs2_meta_inode_buffer(ip, &bh);
if (ret == 0) {
gfs2_trans_add_meta(ip->i_gl, bh);
gfs2_dinode_out(ip, bh->b_data);
brelse(bh);
}
if (need_endtrans)
gfs2_trans_end(sdp);
out:
if (need_unlock)
gfs2_glock_dq_uninit(&gh);
}
/**
* gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
* @sdp: the filesystem
*
* Returns: errno
*/
static int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
{
struct gfs2_holder freeze_gh;
int error;
GFS2: remove transaction glock GFS2 has a transaction glock, which must be grabbed for every transaction, whose purpose is to deal with freezing the filesystem. Aside from this involving a large amount of locking, it is very easy to make the current fsfreeze code hang on unfreezing. This patch rewrites how gfs2 handles freezing the filesystem. The transaction glock is removed. In it's place is a freeze glock, which is cached (but not held) in a shared state by every node in the cluster when the filesystem is mounted. This lock only needs to be grabbed on freezing, and actions which need to be safe from freezing, like recovery. When a node wants to freeze the filesystem, it grabs this glock exclusively. When the freeze glock state changes on the nodes (either from shared to unlocked, or shared to exclusive), the filesystem does a special log flush. gfs2_log_flush() does all the work for flushing out the and shutting down the incore log, and then it tries to grab the freeze glock in a shared state again. Since the filesystem is stuck in gfs2_log_flush, no new transaction can start, and nothing can be written to disk. Unfreezing the filesytem simply involes dropping the freeze glock, allowing gfs2_log_flush() to grab and then release the shared lock, so it is cached for next time. However, in order for the unfreezing ioctl to occur, gfs2 needs to get a shared lock on the filesystem root directory inode to check permissions. If that glock has already been grabbed exclusively, fsfreeze will be unable to get the shared lock and unfreeze the filesystem. In order to allow the unfreeze, this patch makes gfs2 grab a shared lock on the filesystem root directory during the freeze, and hold it until it unfreezes the filesystem. The functions which need to grab a shared lock in order to allow the unfreeze ioctl to be issued now use the lock grabbed by the freeze code instead. The freeze and unfreeze code take care to make sure that this shared lock will not be dropped while another process is using it. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-05-02 07:26:55 +04:00
error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, GL_NOCACHE,
&freeze_gh);
GFS2: remove transaction glock GFS2 has a transaction glock, which must be grabbed for every transaction, whose purpose is to deal with freezing the filesystem. Aside from this involving a large amount of locking, it is very easy to make the current fsfreeze code hang on unfreezing. This patch rewrites how gfs2 handles freezing the filesystem. The transaction glock is removed. In it's place is a freeze glock, which is cached (but not held) in a shared state by every node in the cluster when the filesystem is mounted. This lock only needs to be grabbed on freezing, and actions which need to be safe from freezing, like recovery. When a node wants to freeze the filesystem, it grabs this glock exclusively. When the freeze glock state changes on the nodes (either from shared to unlocked, or shared to exclusive), the filesystem does a special log flush. gfs2_log_flush() does all the work for flushing out the and shutting down the incore log, and then it tries to grab the freeze glock in a shared state again. Since the filesystem is stuck in gfs2_log_flush, no new transaction can start, and nothing can be written to disk. Unfreezing the filesytem simply involes dropping the freeze glock, allowing gfs2_log_flush() to grab and then release the shared lock, so it is cached for next time. However, in order for the unfreezing ioctl to occur, gfs2 needs to get a shared lock on the filesystem root directory inode to check permissions. If that glock has already been grabbed exclusively, fsfreeze will be unable to get the shared lock and unfreeze the filesystem. In order to allow the unfreeze, this patch makes gfs2 grab a shared lock on the filesystem root directory during the freeze, and hold it until it unfreezes the filesystem. The functions which need to grab a shared lock in order to allow the unfreeze ioctl to be issued now use the lock grabbed by the freeze code instead. The freeze and unfreeze code take care to make sure that this shared lock will not be dropped while another process is using it. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-05-02 07:26:55 +04:00
if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
return error;
kthread_stop(sdp->sd_quotad_process);
kthread_stop(sdp->sd_logd_process);
flush_workqueue(gfs2_delete_workqueue);
gfs2_quota_sync(sdp->sd_vfs, 0);
gfs2_statfs_sync(sdp->sd_vfs, 0);
down_write(&sdp->sd_log_flush_lock);
clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
up_write(&sdp->sd_log_flush_lock);
GFS2: remove transaction glock GFS2 has a transaction glock, which must be grabbed for every transaction, whose purpose is to deal with freezing the filesystem. Aside from this involving a large amount of locking, it is very easy to make the current fsfreeze code hang on unfreezing. This patch rewrites how gfs2 handles freezing the filesystem. The transaction glock is removed. In it's place is a freeze glock, which is cached (but not held) in a shared state by every node in the cluster when the filesystem is mounted. This lock only needs to be grabbed on freezing, and actions which need to be safe from freezing, like recovery. When a node wants to freeze the filesystem, it grabs this glock exclusively. When the freeze glock state changes on the nodes (either from shared to unlocked, or shared to exclusive), the filesystem does a special log flush. gfs2_log_flush() does all the work for flushing out the and shutting down the incore log, and then it tries to grab the freeze glock in a shared state again. Since the filesystem is stuck in gfs2_log_flush, no new transaction can start, and nothing can be written to disk. Unfreezing the filesytem simply involes dropping the freeze glock, allowing gfs2_log_flush() to grab and then release the shared lock, so it is cached for next time. However, in order for the unfreezing ioctl to occur, gfs2 needs to get a shared lock on the filesystem root directory inode to check permissions. If that glock has already been grabbed exclusively, fsfreeze will be unable to get the shared lock and unfreeze the filesystem. In order to allow the unfreeze, this patch makes gfs2 grab a shared lock on the filesystem root directory during the freeze, and hold it until it unfreezes the filesystem. The functions which need to grab a shared lock in order to allow the unfreeze ioctl to be issued now use the lock grabbed by the freeze code instead. The freeze and unfreeze code take care to make sure that this shared lock will not be dropped while another process is using it. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-05-02 07:26:55 +04:00
gfs2_log_flush(sdp, NULL, SHUTDOWN_FLUSH);
wait_event(sdp->sd_reserving_log_wait, atomic_read(&sdp->sd_reserving_log) == 0);
GFS2: remove transaction glock GFS2 has a transaction glock, which must be grabbed for every transaction, whose purpose is to deal with freezing the filesystem. Aside from this involving a large amount of locking, it is very easy to make the current fsfreeze code hang on unfreezing. This patch rewrites how gfs2 handles freezing the filesystem. The transaction glock is removed. In it's place is a freeze glock, which is cached (but not held) in a shared state by every node in the cluster when the filesystem is mounted. This lock only needs to be grabbed on freezing, and actions which need to be safe from freezing, like recovery. When a node wants to freeze the filesystem, it grabs this glock exclusively. When the freeze glock state changes on the nodes (either from shared to unlocked, or shared to exclusive), the filesystem does a special log flush. gfs2_log_flush() does all the work for flushing out the and shutting down the incore log, and then it tries to grab the freeze glock in a shared state again. Since the filesystem is stuck in gfs2_log_flush, no new transaction can start, and nothing can be written to disk. Unfreezing the filesytem simply involes dropping the freeze glock, allowing gfs2_log_flush() to grab and then release the shared lock, so it is cached for next time. However, in order for the unfreezing ioctl to occur, gfs2 needs to get a shared lock on the filesystem root directory inode to check permissions. If that glock has already been grabbed exclusively, fsfreeze will be unable to get the shared lock and unfreeze the filesystem. In order to allow the unfreeze, this patch makes gfs2 grab a shared lock on the filesystem root directory during the freeze, and hold it until it unfreezes the filesystem. The functions which need to grab a shared lock in order to allow the unfreeze ioctl to be issued now use the lock grabbed by the freeze code instead. The freeze and unfreeze code take care to make sure that this shared lock will not be dropped while another process is using it. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-05-02 07:26:55 +04:00
gfs2_assert_warn(sdp, atomic_read(&sdp->sd_log_blks_free) == sdp->sd_jdesc->jd_blocks);
if (freeze_gh.gh_gl)
gfs2_glock_dq_uninit(&freeze_gh);
gfs2_quota_cleanup(sdp);
return error;
}
/**
* gfs2_put_super - Unmount the filesystem
* @sb: The VFS superblock
*
*/
static void gfs2_put_super(struct super_block *sb)
{
struct gfs2_sbd *sdp = sb->s_fs_info;
int error;
struct gfs2_jdesc *jd;
/* No more recovery requests */
set_bit(SDF_NORECOVERY, &sdp->sd_flags);
smp_mb();
/* Wait on outstanding recovery */
restart:
spin_lock(&sdp->sd_jindex_spin);
list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
if (!test_bit(JDF_RECOVERY, &jd->jd_flags))
continue;
spin_unlock(&sdp->sd_jindex_spin);
wait_on_bit(&jd->jd_flags, JDF_RECOVERY,
sched: Remove proliferation of wait_on_bit() action functions The current "wait_on_bit" interface requires an 'action' function to be provided which does the actual waiting. There are over 20 such functions, many of them identical. Most cases can be satisfied by one of just two functions, one which uses io_schedule() and one which just uses schedule(). So: Rename wait_on_bit and wait_on_bit_lock to wait_on_bit_action and wait_on_bit_lock_action to make it explicit that they need an action function. Introduce new wait_on_bit{,_lock} and wait_on_bit{,_lock}_io which are *not* given an action function but implicitly use a standard one. The decision to error-out if a signal is pending is now made based on the 'mode' argument rather than being encoded in the action function. All instances of the old wait_on_bit and wait_on_bit_lock which can use the new version have been changed accordingly and their action functions have been discarded. wait_on_bit{_lock} does not return any specific error code in the event of a signal so the caller must check for non-zero and interpolate their own error code as appropriate. The wait_on_bit() call in __fscache_wait_on_invalidate() was ambiguous as it specified TASK_UNINTERRUPTIBLE but used fscache_wait_bit_interruptible as an action function. David Howells confirms this should be uniformly "uninterruptible" The main remaining user of wait_on_bit{,_lock}_action is NFS which needs to use a freezer-aware schedule() call. A comment in fs/gfs2/glock.c notes that having multiple 'action' functions is useful as they display differently in the 'wchan' field of 'ps'. (and /proc/$PID/wchan). As the new bit_wait{,_io} functions are tagged "__sched", they will not show up at all, but something higher in the stack. So the distinction will still be visible, only with different function names (gds2_glock_wait versus gfs2_glock_dq_wait in the gfs2/glock.c case). Since first version of this patch (against 3.15) two new action functions appeared, on in NFS and one in CIFS. CIFS also now uses an action function that makes the same freezer aware schedule call as NFS. Signed-off-by: NeilBrown <neilb@suse.de> Acked-by: David Howells <dhowells@redhat.com> (fscache, keys) Acked-by: Steven Whitehouse <swhiteho@redhat.com> (gfs2) Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Steve French <sfrench@samba.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20140707051603.28027.72349.stgit@notabene.brown Signed-off-by: Ingo Molnar <mingo@kernel.org>
2014-07-07 09:16:04 +04:00
TASK_UNINTERRUPTIBLE);
goto restart;
}
spin_unlock(&sdp->sd_jindex_spin);
if (!(sb->s_flags & MS_RDONLY)) {
error = gfs2_make_fs_ro(sdp);
if (error)
gfs2_io_error(sdp);
}
/* At this point, we're through modifying the disk */
/* Release stuff */
iput(sdp->sd_jindex);
iput(sdp->sd_statfs_inode);
iput(sdp->sd_rindex);
iput(sdp->sd_quota_inode);
gfs2_glock_put(sdp->sd_rename_gl);
GFS2: remove transaction glock GFS2 has a transaction glock, which must be grabbed for every transaction, whose purpose is to deal with freezing the filesystem. Aside from this involving a large amount of locking, it is very easy to make the current fsfreeze code hang on unfreezing. This patch rewrites how gfs2 handles freezing the filesystem. The transaction glock is removed. In it's place is a freeze glock, which is cached (but not held) in a shared state by every node in the cluster when the filesystem is mounted. This lock only needs to be grabbed on freezing, and actions which need to be safe from freezing, like recovery. When a node wants to freeze the filesystem, it grabs this glock exclusively. When the freeze glock state changes on the nodes (either from shared to unlocked, or shared to exclusive), the filesystem does a special log flush. gfs2_log_flush() does all the work for flushing out the and shutting down the incore log, and then it tries to grab the freeze glock in a shared state again. Since the filesystem is stuck in gfs2_log_flush, no new transaction can start, and nothing can be written to disk. Unfreezing the filesytem simply involes dropping the freeze glock, allowing gfs2_log_flush() to grab and then release the shared lock, so it is cached for next time. However, in order for the unfreezing ioctl to occur, gfs2 needs to get a shared lock on the filesystem root directory inode to check permissions. If that glock has already been grabbed exclusively, fsfreeze will be unable to get the shared lock and unfreeze the filesystem. In order to allow the unfreeze, this patch makes gfs2 grab a shared lock on the filesystem root directory during the freeze, and hold it until it unfreezes the filesystem. The functions which need to grab a shared lock in order to allow the unfreeze ioctl to be issued now use the lock grabbed by the freeze code instead. The freeze and unfreeze code take care to make sure that this shared lock will not be dropped while another process is using it. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-05-02 07:26:55 +04:00
gfs2_glock_put(sdp->sd_freeze_gl);
if (!sdp->sd_args.ar_spectator) {
gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
iput(sdp->sd_sc_inode);
iput(sdp->sd_qc_inode);
}
gfs2_glock_dq_uninit(&sdp->sd_live_gh);
gfs2_clear_rgrpd(sdp);
gfs2_jindex_free(sdp);
/* Take apart glock structures and buffer lists */
gfs2_gl_hash_clear(sdp);
/* Unmount the locking protocol */
gfs2_lm_unmount(sdp);
/* At this point, we're through participating in the lockspace */
gfs2_sys_fs_del(sdp);
}
/**
* gfs2_sync_fs - sync the filesystem
* @sb: the superblock
*
* Flushes the log to disk.
*/
static int gfs2_sync_fs(struct super_block *sb, int wait)
{
struct gfs2_sbd *sdp = sb->s_fs_info;
gfs2_quota_sync(sb, -1);
if (wait && sdp)
GFS2: remove transaction glock GFS2 has a transaction glock, which must be grabbed for every transaction, whose purpose is to deal with freezing the filesystem. Aside from this involving a large amount of locking, it is very easy to make the current fsfreeze code hang on unfreezing. This patch rewrites how gfs2 handles freezing the filesystem. The transaction glock is removed. In it's place is a freeze glock, which is cached (but not held) in a shared state by every node in the cluster when the filesystem is mounted. This lock only needs to be grabbed on freezing, and actions which need to be safe from freezing, like recovery. When a node wants to freeze the filesystem, it grabs this glock exclusively. When the freeze glock state changes on the nodes (either from shared to unlocked, or shared to exclusive), the filesystem does a special log flush. gfs2_log_flush() does all the work for flushing out the and shutting down the incore log, and then it tries to grab the freeze glock in a shared state again. Since the filesystem is stuck in gfs2_log_flush, no new transaction can start, and nothing can be written to disk. Unfreezing the filesytem simply involes dropping the freeze glock, allowing gfs2_log_flush() to grab and then release the shared lock, so it is cached for next time. However, in order for the unfreezing ioctl to occur, gfs2 needs to get a shared lock on the filesystem root directory inode to check permissions. If that glock has already been grabbed exclusively, fsfreeze will be unable to get the shared lock and unfreeze the filesystem. In order to allow the unfreeze, this patch makes gfs2 grab a shared lock on the filesystem root directory during the freeze, and hold it until it unfreezes the filesystem. The functions which need to grab a shared lock in order to allow the unfreeze ioctl to be issued now use the lock grabbed by the freeze code instead. The freeze and unfreeze code take care to make sure that this shared lock will not be dropped while another process is using it. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-05-02 07:26:55 +04:00
gfs2_log_flush(sdp, NULL, NORMAL_FLUSH);
return 0;
}
void gfs2_freeze_func(struct work_struct *work)
{
int error;
struct gfs2_holder freeze_gh;
struct gfs2_sbd *sdp = container_of(work, struct gfs2_sbd, sd_freeze_work);
struct super_block *sb = sdp->sd_vfs;
atomic_inc(&sb->s_active);
error = gfs2_glock_nq_init(sdp->sd_freeze_gl, LM_ST_SHARED, 0,
&freeze_gh);
if (error) {
printk(KERN_INFO "GFS2: couln't get freeze lock : %d\n", error);
gfs2_assert_withdraw(sdp, 0);
}
else {
atomic_set(&sdp->sd_freeze_state, SFS_UNFROZEN);
error = thaw_super(sb);
if (error) {
printk(KERN_INFO "GFS2: couldn't thaw filesystem: %d\n",
error);
gfs2_assert_withdraw(sdp, 0);
}
if (!test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags))
freeze_gh.gh_flags |= GL_NOCACHE;
gfs2_glock_dq_uninit(&freeze_gh);
}
deactivate_super(sb);
return;
}
/**
* gfs2_freeze - prevent further writes to the filesystem
* @sb: the VFS structure for the filesystem
*
*/
static int gfs2_freeze(struct super_block *sb)
{
struct gfs2_sbd *sdp = sb->s_fs_info;
int error = 0;
mutex_lock(&sdp->sd_freeze_mutex);
if (atomic_read(&sdp->sd_freeze_state) != SFS_UNFROZEN)
goto out;
if (test_bit(SDF_SHUTDOWN, &sdp->sd_flags)) {
error = -EINVAL;
goto out;
}
for (;;) {
error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
if (!error)
break;
switch (error) {
case -EBUSY:
fs_err(sdp, "waiting for recovery before freeze\n");
break;
default:
fs_err(sdp, "error freezing FS: %d\n", error);
break;
}
fs_err(sdp, "retrying...\n");
msleep(1000);
}
error = 0;
out:
mutex_unlock(&sdp->sd_freeze_mutex);
return error;
}
/**
* gfs2_unfreeze - reallow writes to the filesystem
* @sb: the VFS structure for the filesystem
*
*/
static int gfs2_unfreeze(struct super_block *sb)
{
struct gfs2_sbd *sdp = sb->s_fs_info;
mutex_lock(&sdp->sd_freeze_mutex);
if (atomic_read(&sdp->sd_freeze_state) != SFS_FROZEN ||
sdp->sd_freeze_gh.gh_gl == NULL) {
mutex_unlock(&sdp->sd_freeze_mutex);
return 0;
}
gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
mutex_unlock(&sdp->sd_freeze_mutex);
return 0;
}
/**
* statfs_fill - fill in the sg for a given RG
* @rgd: the RG
* @sc: the sc structure
*
* Returns: 0 on success, -ESTALE if the LVB is invalid
*/
static int statfs_slow_fill(struct gfs2_rgrpd *rgd,
struct gfs2_statfs_change_host *sc)
{
gfs2_rgrp_verify(rgd);
sc->sc_total += rgd->rd_data;
sc->sc_free += rgd->rd_free;
sc->sc_dinodes += rgd->rd_dinodes;
return 0;
}
/**
* gfs2_statfs_slow - Stat a filesystem using asynchronous locking
* @sdp: the filesystem
* @sc: the sc info that will be returned
*
* Any error (other than a signal) will cause this routine to fall back
* to the synchronous version.
*
* FIXME: This really shouldn't busy wait like this.
*
* Returns: errno
*/
static int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
{
struct gfs2_rgrpd *rgd_next;
struct gfs2_holder *gha, *gh;
unsigned int slots = 64;
unsigned int x;
int done;
int error = 0, err;
memset(sc, 0, sizeof(struct gfs2_statfs_change_host));
gha = kcalloc(slots, sizeof(struct gfs2_holder), GFP_KERNEL);
if (!gha)
return -ENOMEM;
rgd_next = gfs2_rgrpd_get_first(sdp);
for (;;) {
done = 1;
for (x = 0; x < slots; x++) {
gh = gha + x;
if (gh->gh_gl && gfs2_glock_poll(gh)) {
err = gfs2_glock_wait(gh);
if (err) {
gfs2_holder_uninit(gh);
error = err;
} else {
if (!error)
error = statfs_slow_fill(
gh->gh_gl->gl_object, sc);
gfs2_glock_dq_uninit(gh);
}
}
if (gh->gh_gl)
done = 0;
else if (rgd_next && !error) {
error = gfs2_glock_nq_init(rgd_next->rd_gl,
LM_ST_SHARED,
GL_ASYNC,
gh);
rgd_next = gfs2_rgrpd_get_next(rgd_next);
done = 0;
}
if (signal_pending(current))
error = -ERESTARTSYS;
}
if (done)
break;
yield();
}
kfree(gha);
return error;
}
/**
* gfs2_statfs_i - Do a statfs
* @sdp: the filesystem
* @sg: the sg structure
*
* Returns: errno
*/
static int gfs2_statfs_i(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
{
struct gfs2_statfs_change_host *m_sc = &sdp->sd_statfs_master;
struct gfs2_statfs_change_host *l_sc = &sdp->sd_statfs_local;
spin_lock(&sdp->sd_statfs_spin);
*sc = *m_sc;
sc->sc_total += l_sc->sc_total;
sc->sc_free += l_sc->sc_free;
sc->sc_dinodes += l_sc->sc_dinodes;
spin_unlock(&sdp->sd_statfs_spin);
if (sc->sc_free < 0)
sc->sc_free = 0;
if (sc->sc_free > sc->sc_total)
sc->sc_free = sc->sc_total;
if (sc->sc_dinodes < 0)
sc->sc_dinodes = 0;
return 0;
}
/**
* gfs2_statfs - Gather and return stats about the filesystem
* @sb: The superblock
* @statfsbuf: The buffer
*
* Returns: 0 on success or error code
*/
static int gfs2_statfs(struct dentry *dentry, struct kstatfs *buf)
{
struct super_block *sb = d_inode(dentry)->i_sb;
struct gfs2_sbd *sdp = sb->s_fs_info;
struct gfs2_statfs_change_host sc;
int error;
error = gfs2_rindex_update(sdp);
if (error)
return error;
if (gfs2_tune_get(sdp, gt_statfs_slow))
error = gfs2_statfs_slow(sdp, &sc);
else
error = gfs2_statfs_i(sdp, &sc);
if (error)
return error;
buf->f_type = GFS2_MAGIC;
buf->f_bsize = sdp->sd_sb.sb_bsize;
buf->f_blocks = sc.sc_total;
buf->f_bfree = sc.sc_free;
buf->f_bavail = sc.sc_free;
buf->f_files = sc.sc_dinodes + sc.sc_free;
buf->f_ffree = sc.sc_free;
buf->f_namelen = GFS2_FNAMESIZE;
return 0;
}
/**
* gfs2_remount_fs - called when the FS is remounted
* @sb: the filesystem
* @flags: the remount flags
* @data: extra data passed in (not used right now)
*
* Returns: errno
*/
static int gfs2_remount_fs(struct super_block *sb, int *flags, char *data)
{
struct gfs2_sbd *sdp = sb->s_fs_info;
struct gfs2_args args = sdp->sd_args; /* Default to current settings */
struct gfs2_tune *gt = &sdp->sd_tune;
int error;
fs: push sync_filesystem() down to the file system's remount_fs() Previously, the no-op "mount -o mount /dev/xxx" operation when the file system is already mounted read-write causes an implied, unconditional syncfs(). This seems pretty stupid, and it's certainly documented or guaraunteed to do this, nor is it particularly useful, except in the case where the file system was mounted rw and is getting remounted read-only. However, it's possible that there might be some file systems that are actually depending on this behavior. In most file systems, it's probably fine to only call sync_filesystem() when transitioning from read-write to read-only, and there are some file systems where this is not needed at all (for example, for a pseudo-filesystem or something like romfs). Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Cc: linux-fsdevel@vger.kernel.org Cc: Christoph Hellwig <hch@infradead.org> Cc: Artem Bityutskiy <dedekind1@gmail.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Evgeniy Dushistov <dushistov@mail.ru> Cc: Jan Kara <jack@suse.cz> Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> Cc: Anders Larsen <al@alarsen.net> Cc: Phillip Lougher <phillip@squashfs.org.uk> Cc: Kees Cook <keescook@chromium.org> Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz> Cc: Petr Vandrovec <petr@vandrovec.name> Cc: xfs@oss.sgi.com Cc: linux-btrfs@vger.kernel.org Cc: linux-cifs@vger.kernel.org Cc: samba-technical@lists.samba.org Cc: codalist@coda.cs.cmu.edu Cc: linux-ext4@vger.kernel.org Cc: linux-f2fs-devel@lists.sourceforge.net Cc: fuse-devel@lists.sourceforge.net Cc: cluster-devel@redhat.com Cc: linux-mtd@lists.infradead.org Cc: jfs-discussion@lists.sourceforge.net Cc: linux-nfs@vger.kernel.org Cc: linux-nilfs@vger.kernel.org Cc: linux-ntfs-dev@lists.sourceforge.net Cc: ocfs2-devel@oss.oracle.com Cc: reiserfs-devel@vger.kernel.org
2014-03-13 18:14:33 +04:00
sync_filesystem(sb);
spin_lock(&gt->gt_spin);
args.ar_commit = gt->gt_logd_secs;
args.ar_quota_quantum = gt->gt_quota_quantum;
if (gt->gt_statfs_slow)
args.ar_statfs_quantum = 0;
else
args.ar_statfs_quantum = gt->gt_statfs_quantum;
spin_unlock(&gt->gt_spin);
error = gfs2_mount_args(&args, data);
if (error)
return error;
/* Not allowed to change locking details */
if (strcmp(args.ar_lockproto, sdp->sd_args.ar_lockproto) ||
strcmp(args.ar_locktable, sdp->sd_args.ar_locktable) ||
strcmp(args.ar_hostdata, sdp->sd_args.ar_hostdata))
return -EINVAL;
/* Some flags must not be changed */
if (args_neq(&args, &sdp->sd_args, spectator) ||
args_neq(&args, &sdp->sd_args, localflocks) ||
args_neq(&args, &sdp->sd_args, meta))
return -EINVAL;
if (sdp->sd_args.ar_spectator)
*flags |= MS_RDONLY;
if ((sb->s_flags ^ *flags) & MS_RDONLY) {
if (*flags & MS_RDONLY)
error = gfs2_make_fs_ro(sdp);
else
error = gfs2_make_fs_rw(sdp);
if (error)
return error;
}
sdp->sd_args = args;
if (sdp->sd_args.ar_posix_acl)
sb->s_flags |= MS_POSIXACL;
else
sb->s_flags &= ~MS_POSIXACL;
if (sdp->sd_args.ar_nobarrier)
set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
else
clear_bit(SDF_NOBARRIERS, &sdp->sd_flags);
spin_lock(&gt->gt_spin);
gt->gt_logd_secs = args.ar_commit;
gt->gt_quota_quantum = args.ar_quota_quantum;
if (args.ar_statfs_quantum) {
gt->gt_statfs_slow = 0;
gt->gt_statfs_quantum = args.ar_statfs_quantum;
}
else {
gt->gt_statfs_slow = 1;
gt->gt_statfs_quantum = 30;
}
spin_unlock(&gt->gt_spin);
gfs2_online_uevent(sdp);
return 0;
}
/**
* gfs2_drop_inode - Drop an inode (test for remote unlink)
* @inode: The inode to drop
*
* If we've received a callback on an iopen lock then its because a
* remote node tried to deallocate the inode but failed due to this node
* still having the inode open. Here we mark the link count zero
* since we know that it must have reached zero if the GLF_DEMOTE flag
* is set on the iopen glock. If we didn't do a disk read since the
* remote node removed the final link then we might otherwise miss
* this event. This check ensures that this node will deallocate the
* inode's blocks, or alternatively pass the baton on to another
* node for later deallocation.
*/
static int gfs2_drop_inode(struct inode *inode)
{
struct gfs2_inode *ip = GFS2_I(inode);
if (!test_bit(GIF_FREE_VFS_INODE, &ip->i_flags) && inode->i_nlink) {
struct gfs2_glock *gl = ip->i_iopen_gh.gh_gl;
if (gl && test_bit(GLF_DEMOTE, &gl->gl_flags))
clear_nlink(inode);
}
return generic_drop_inode(inode);
}
static int is_ancestor(const struct dentry *d1, const struct dentry *d2)
{
do {
if (d1 == d2)
return 1;
d1 = d1->d_parent;
} while (!IS_ROOT(d1));
return 0;
}
/**
* gfs2_show_options - Show mount options for /proc/mounts
* @s: seq_file structure
* @root: root of this (sub)tree
*
* Returns: 0 on success or error code
*/
static int gfs2_show_options(struct seq_file *s, struct dentry *root)
{
struct gfs2_sbd *sdp = root->d_sb->s_fs_info;
struct gfs2_args *args = &sdp->sd_args;
int val;
if (is_ancestor(root, sdp->sd_master_dir))
seq_puts(s, ",meta");
if (args->ar_lockproto[0])
seq_printf(s, ",lockproto=%s", args->ar_lockproto);
if (args->ar_locktable[0])
seq_printf(s, ",locktable=%s", args->ar_locktable);
if (args->ar_hostdata[0])
seq_printf(s, ",hostdata=%s", args->ar_hostdata);
if (args->ar_spectator)
seq_puts(s, ",spectator");
if (args->ar_localflocks)
seq_puts(s, ",localflocks");
if (args->ar_debug)
seq_puts(s, ",debug");
if (args->ar_posix_acl)
seq_puts(s, ",acl");
if (args->ar_quota != GFS2_QUOTA_DEFAULT) {
char *state;
switch (args->ar_quota) {
case GFS2_QUOTA_OFF:
state = "off";
break;
case GFS2_QUOTA_ACCOUNT:
state = "account";
break;
case GFS2_QUOTA_ON:
state = "on";
break;
default:
state = "unknown";
break;
}
seq_printf(s, ",quota=%s", state);
}
if (args->ar_suiddir)
seq_puts(s, ",suiddir");
if (args->ar_data != GFS2_DATA_DEFAULT) {
char *state;
switch (args->ar_data) {
case GFS2_DATA_WRITEBACK:
state = "writeback";
break;
case GFS2_DATA_ORDERED:
state = "ordered";
break;
default:
state = "unknown";
break;
}
seq_printf(s, ",data=%s", state);
}
if (args->ar_discard)
seq_puts(s, ",discard");
val = sdp->sd_tune.gt_logd_secs;
if (val != 30)
seq_printf(s, ",commit=%d", val);
val = sdp->sd_tune.gt_statfs_quantum;
if (val != 30)
seq_printf(s, ",statfs_quantum=%d", val);
else if (sdp->sd_tune.gt_statfs_slow)
seq_puts(s, ",statfs_quantum=0");
val = sdp->sd_tune.gt_quota_quantum;
if (val != 60)
seq_printf(s, ",quota_quantum=%d", val);
if (args->ar_statfs_percent)
seq_printf(s, ",statfs_percent=%d", args->ar_statfs_percent);
if (args->ar_errors != GFS2_ERRORS_DEFAULT) {
const char *state;
switch (args->ar_errors) {
case GFS2_ERRORS_WITHDRAW:
state = "withdraw";
break;
case GFS2_ERRORS_PANIC:
state = "panic";
break;
default:
state = "unknown";
break;
}
seq_printf(s, ",errors=%s", state);
}
if (test_bit(SDF_NOBARRIERS, &sdp->sd_flags))
seq_puts(s, ",nobarrier");
if (test_bit(SDF_DEMOTE, &sdp->sd_flags))
seq_puts(s, ",demote_interface_used");
if (args->ar_rgrplvb)
seq_puts(s, ",rgrplvb");
return 0;
}
static void gfs2_final_release_pages(struct gfs2_inode *ip)
{
struct inode *inode = &ip->i_inode;
struct gfs2_glock *gl = ip->i_gl;
truncate_inode_pages(gfs2_glock2aspace(ip->i_gl), 0);
truncate_inode_pages(&inode->i_data, 0);
if (atomic_read(&gl->gl_revokes) == 0) {
clear_bit(GLF_LFLUSH, &gl->gl_flags);
clear_bit(GLF_DIRTY, &gl->gl_flags);
}
}
static int gfs2_dinode_dealloc(struct gfs2_inode *ip)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct gfs2_rgrpd *rgd;
struct gfs2_holder gh;
int error;
if (gfs2_get_inode_blocks(&ip->i_inode) != 1) {
gfs2_consist_inode(ip);
return -EIO;
}
error = gfs2_rindex_update(sdp);
if (error)
return error;
error = gfs2_quota_hold(ip, NO_UID_QUOTA_CHANGE, NO_GID_QUOTA_CHANGE);
if (error)
return error;
rgd = gfs2_blk2rgrpd(sdp, ip->i_no_addr, 1);
if (!rgd) {
gfs2_consist_inode(ip);
error = -EIO;
goto out_qs;
}
error = gfs2_glock_nq_init(rgd->rd_gl, LM_ST_EXCLUSIVE, 0, &gh);
if (error)
goto out_qs;
error = gfs2_trans_begin(sdp, RES_RG_BIT + RES_STATFS + RES_QUOTA,
sdp->sd_jdesc->jd_blocks);
if (error)
goto out_rg_gunlock;
gfs2_free_di(rgd, ip);
gfs2_final_release_pages(ip);
gfs2_trans_end(sdp);
out_rg_gunlock:
gfs2_glock_dq_uninit(&gh);
out_qs:
gfs2_quota_unhold(ip);
return error;
}
/**
* gfs2_evict_inode - Remove an inode from cache
* @inode: The inode to evict
*
* There are three cases to consider:
* 1. i_nlink == 0, we are final opener (and must deallocate)
* 2. i_nlink == 0, we are not the final opener (and cannot deallocate)
* 3. i_nlink > 0
*
* If the fs is read only, then we have to treat all cases as per #3
* since we are unable to do any deallocation. The inode will be
* deallocated by the next read/write node to attempt an allocation
* in the same resource group
*
* We have to (at the moment) hold the inodes main lock to cover
* the gap between unlocking the shared lock on the iopen lock and
* taking the exclusive lock. I'd rather do a shared -> exclusive
* conversion on the iopen lock, but we can change that later. This
* is safe, just less efficient.
*/
static void gfs2_evict_inode(struct inode *inode)
{
struct super_block *sb = inode->i_sb;
struct gfs2_sbd *sdp = sb->s_fs_info;
struct gfs2_inode *ip = GFS2_I(inode);
struct gfs2_holder gh;
int error;
if (test_bit(GIF_FREE_VFS_INODE, &ip->i_flags)) {
clear_inode(inode);
return;
}
if (inode->i_nlink || (sb->s_flags & MS_RDONLY))
goto out;
/* Must not read inode block until block type has been verified */
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_SKIP, &gh);
if (unlikely(error)) {
ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
gfs2_glock_dq_uninit(&ip->i_iopen_gh);
goto out;
}
if (!test_bit(GIF_ALLOC_FAILED, &ip->i_flags)) {
error = gfs2_check_blk_type(sdp, ip->i_no_addr, GFS2_BLKST_UNLINKED);
if (error)
goto out_truncate;
}
if (test_bit(GIF_INVALID, &ip->i_flags)) {
error = gfs2_inode_refresh(ip);
if (error)
goto out_truncate;
}
ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
gfs2_glock_dq_wait(&ip->i_iopen_gh);
gfs2_holder_reinit(LM_ST_EXCLUSIVE, LM_FLAG_TRY_1CB | GL_NOCACHE, &ip->i_iopen_gh);
error = gfs2_glock_nq(&ip->i_iopen_gh);
if (error)
goto out_truncate;
/* Case 1 starts here */
if (S_ISDIR(inode->i_mode) &&
(ip->i_diskflags & GFS2_DIF_EXHASH)) {
error = gfs2_dir_exhash_dealloc(ip);
if (error)
goto out_unlock;
}
if (ip->i_eattr) {
error = gfs2_ea_dealloc(ip);
if (error)
goto out_unlock;
}
if (!gfs2_is_stuffed(ip)) {
error = gfs2_file_dealloc(ip);
if (error)
goto out_unlock;
}
error = gfs2_dinode_dealloc(ip);
goto out_unlock;
out_truncate:
GFS2: remove transaction glock GFS2 has a transaction glock, which must be grabbed for every transaction, whose purpose is to deal with freezing the filesystem. Aside from this involving a large amount of locking, it is very easy to make the current fsfreeze code hang on unfreezing. This patch rewrites how gfs2 handles freezing the filesystem. The transaction glock is removed. In it's place is a freeze glock, which is cached (but not held) in a shared state by every node in the cluster when the filesystem is mounted. This lock only needs to be grabbed on freezing, and actions which need to be safe from freezing, like recovery. When a node wants to freeze the filesystem, it grabs this glock exclusively. When the freeze glock state changes on the nodes (either from shared to unlocked, or shared to exclusive), the filesystem does a special log flush. gfs2_log_flush() does all the work for flushing out the and shutting down the incore log, and then it tries to grab the freeze glock in a shared state again. Since the filesystem is stuck in gfs2_log_flush, no new transaction can start, and nothing can be written to disk. Unfreezing the filesytem simply involes dropping the freeze glock, allowing gfs2_log_flush() to grab and then release the shared lock, so it is cached for next time. However, in order for the unfreezing ioctl to occur, gfs2 needs to get a shared lock on the filesystem root directory inode to check permissions. If that glock has already been grabbed exclusively, fsfreeze will be unable to get the shared lock and unfreeze the filesystem. In order to allow the unfreeze, this patch makes gfs2 grab a shared lock on the filesystem root directory during the freeze, and hold it until it unfreezes the filesystem. The functions which need to grab a shared lock in order to allow the unfreeze ioctl to be issued now use the lock grabbed by the freeze code instead. The freeze and unfreeze code take care to make sure that this shared lock will not be dropped while another process is using it. Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2014-05-02 07:26:55 +04:00
gfs2_log_flush(sdp, ip->i_gl, NORMAL_FLUSH);
if (test_bit(GLF_DIRTY, &ip->i_gl->gl_flags)) {
struct address_space *metamapping = gfs2_glock2aspace(ip->i_gl);
filemap_fdatawrite(metamapping);
filemap_fdatawait(metamapping);
}
write_inode_now(inode, 1);
gfs2_ail_flush(ip->i_gl, 0);
/* Case 2 starts here */
error = gfs2_trans_begin(sdp, 0, sdp->sd_jdesc->jd_blocks);
if (error)
goto out_unlock;
/* Needs to be done before glock release & also in a transaction */
truncate_inode_pages(&inode->i_data, 0);
gfs2_trans_end(sdp);
out_unlock:
/* Error path for case 1 */
if (gfs2_rs_active(ip->i_res))
gfs2_rs_deltree(ip->i_res);
if (test_bit(HIF_HOLDER, &ip->i_iopen_gh.gh_iflags)) {
ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
gfs2_glock_dq(&ip->i_iopen_gh);
}
gfs2_holder_uninit(&ip->i_iopen_gh);
gfs2_glock_dq_uninit(&gh);
if (error && error != GLR_TRYFAILED && error != -EROFS)
fs_warn(sdp, "gfs2_evict_inode: %d\n", error);
out:
/* Case 3 starts here */
mm + fs: store shadow entries in page cache Reclaim will be leaving shadow entries in the page cache radix tree upon evicting the real page. As those pages are found from the LRU, an iput() can lead to the inode being freed concurrently. At this point, reclaim must no longer install shadow pages because the inode freeing code needs to ensure the page tree is really empty. Add an address_space flag, AS_EXITING, that the inode freeing code sets under the tree lock before doing the final truncate. Reclaim will check for this flag before installing shadow pages. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Reviewed-by: Rik van Riel <riel@redhat.com> Reviewed-by: Minchan Kim <minchan@kernel.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Bob Liu <bob.liu@oracle.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Greg Thelen <gthelen@google.com> Cc: Hugh Dickins <hughd@google.com> Cc: Jan Kara <jack@suse.cz> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Luigi Semenzato <semenzato@google.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Metin Doslu <metin@citusdata.com> Cc: Michel Lespinasse <walken@google.com> Cc: Ozgun Erdogan <ozgun@citusdata.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Roman Gushchin <klamm@yandex-team.ru> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-04 01:47:49 +04:00
truncate_inode_pages_final(&inode->i_data);
gfs2_rs_delete(ip, NULL);
gfs2_ordered_del_inode(ip);
clear_inode(inode);
gfs2_dir_hash_inval(ip);
ip->i_gl->gl_object = NULL;
workqueue: deprecate flush[_delayed]_work_sync() flush[_delayed]_work_sync() are now spurious. Mark them deprecated and convert all users to flush[_delayed]_work(). If you're cc'd and wondering what's going on: Now all workqueues are non-reentrant and the regular flushes guarantee that the work item is not pending or running on any CPU on return, so there's no reason to use the sync flushes at all and they're going away. This patch doesn't make any functional difference. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Russell King <linux@arm.linux.org.uk> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Ian Campbell <ian.campbell@citrix.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Mattia Dongili <malattia@linux.it> Cc: Kent Yoder <key@linux.vnet.ibm.com> Cc: David Airlie <airlied@linux.ie> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Karsten Keil <isdn@linux-pingi.de> Cc: Bryan Wu <bryan.wu@canonical.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Alasdair Kergon <agk@redhat.com> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de> Cc: David Woodhouse <dwmw2@infradead.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: linux-wireless@vger.kernel.org Cc: Anton Vorontsov <cbou@mail.ru> Cc: Sangbeom Kim <sbkim73@samsung.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Eric Van Hensbergen <ericvh@gmail.com> Cc: Takashi Iwai <tiwai@suse.de> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Petr Vandrovec <petr@vandrovec.name> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Avi Kivity <avi@redhat.com>
2012-08-21 01:51:24 +04:00
flush_delayed_work(&ip->i_gl->gl_work);
gfs2_glock_add_to_lru(ip->i_gl);
gfs2_glock_put(ip->i_gl);
ip->i_gl = NULL;
if (ip->i_iopen_gh.gh_gl) {
ip->i_iopen_gh.gh_gl->gl_object = NULL;
ip->i_iopen_gh.gh_flags |= GL_NOCACHE;
gfs2_glock_dq_uninit(&ip->i_iopen_gh);
}
}
static struct inode *gfs2_alloc_inode(struct super_block *sb)
{
struct gfs2_inode *ip;
ip = kmem_cache_alloc(gfs2_inode_cachep, GFP_KERNEL);
if (ip) {
ip->i_flags = 0;
ip->i_gl = NULL;
ip->i_rgd = NULL;
ip->i_res = NULL;
}
return &ip->i_inode;
}
2011-01-07 09:49:49 +03:00
static void gfs2_i_callback(struct rcu_head *head)
{
2011-01-07 09:49:49 +03:00
struct inode *inode = container_of(head, struct inode, i_rcu);
kmem_cache_free(gfs2_inode_cachep, inode);
}
2011-01-07 09:49:49 +03:00
static void gfs2_destroy_inode(struct inode *inode)
{
call_rcu(&inode->i_rcu, gfs2_i_callback);
}
const struct super_operations gfs2_super_ops = {
.alloc_inode = gfs2_alloc_inode,
.destroy_inode = gfs2_destroy_inode,
.write_inode = gfs2_write_inode,
.dirty_inode = gfs2_dirty_inode,
.evict_inode = gfs2_evict_inode,
.put_super = gfs2_put_super,
.sync_fs = gfs2_sync_fs,
.freeze_super = gfs2_freeze,
.thaw_super = gfs2_unfreeze,
.statfs = gfs2_statfs,
.remount_fs = gfs2_remount_fs,
.drop_inode = gfs2_drop_inode,
.show_options = gfs2_show_options,
};