linux-brain/fs/gfs2/ops_fstype.c
Bob Peterson ad26967b9a gfs2: Use async glocks for rename
Because s_vfs_rename_mutex is not cluster-wide, multiple nodes can
reverse the roles of which directories are "old" and which are "new" for
the purposes of rename. This can cause deadlocks where two nodes end up
waiting for each other.

There can be several layers of directory dependencies across many nodes.

This patch fixes the problem by acquiring all gfs2_rename's inode glocks
asychronously and waiting for all glocks to be acquired.  That way all
inodes are locked regardless of the order.

The timeout value for multiple asynchronous glocks is calculated to be
the total of the individual wait times for each glock times two.

Since gfs2_exchange is very similar to gfs2_rename, both functions are
patched in the same way.

A new async glock wait queue, sd_async_glock_wait, keeps a list of
waiters for these events. If gfs2's holder_wake function detects an
async holder, it wakes up any waiters for the event. The waiter only
tests whether any of its requests are still pending.

Since the glocks are sent to dlm asychronously, the wait function needs
to check to see which glocks, if any, were granted.

If a glock is granted by dlm (and therefore held), its minimum hold time
is checked and adjusted as necessary, as other glock grants do.

If the event times out, all glocks held thus far must be dequeued to
resolve any existing deadlocks.  Then, if there are any outstanding
locking requests, we need to loop around and wait for dlm to respond to
those requests too.  After we release all requests, we return -ESTALE to
the caller (vfs rename) which loops around and retries the request.

    Node1           Node2
    ---------       ---------
1.  Enqueue A       Enqueue B
2.  Enqueue B       Enqueue A
3.  A granted
6.                  B granted
7.  Wait for B
8.                  Wait for A
9.                  A times out (since Node 1 holds A)
10.                 Dequeue B (since it was granted)
11.                 Wait for all requests from DLM
12. B Granted (since Node2 released it in step 10)
13. Rename
14. Dequeue A
15.                 DLM Grants A
16.                 Dequeue A (due to the timeout and since we
                    no longer have B held for our task).
17. Dequeue B
18.                 Return -ESTALE to vfs
19.                 VFS retries the operation, goto step 1.

This release-all-locks / acquire-all-locks may slow rename / exchange
down as both nodes struggle in the same way and do the same thing.
However, this will only happen when there is contention for the same
inodes, which ought to be rare.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2019-09-04 20:22:17 +02:00

1399 lines
35 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/blkdev.h>
#include <linux/kthread.h>
#include <linux/export.h>
#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/gfs2_ondisk.h>
#include <linux/quotaops.h>
#include <linux/lockdep.h>
#include <linux/module.h>
#include <linux/backing-dev.h>
#include "gfs2.h"
#include "incore.h"
#include "bmap.h"
#include "glock.h"
#include "glops.h"
#include "inode.h"
#include "recovery.h"
#include "rgrp.h"
#include "super.h"
#include "sys.h"
#include "util.h"
#include "log.h"
#include "quota.h"
#include "dir.h"
#include "meta_io.h"
#include "trace_gfs2.h"
#include "lops.h"
#define DO 0
#define UNDO 1
/**
* gfs2_tune_init - Fill a gfs2_tune structure with default values
* @gt: tune
*
*/
static void gfs2_tune_init(struct gfs2_tune *gt)
{
spin_lock_init(&gt->gt_spin);
gt->gt_quota_warn_period = 10;
gt->gt_quota_scale_num = 1;
gt->gt_quota_scale_den = 1;
gt->gt_new_files_jdata = 0;
gt->gt_max_readahead = BIT(18);
gt->gt_complain_secs = 10;
}
void free_sbd(struct gfs2_sbd *sdp)
{
if (sdp->sd_lkstats)
free_percpu(sdp->sd_lkstats);
kfree(sdp);
}
static struct gfs2_sbd *init_sbd(struct super_block *sb)
{
struct gfs2_sbd *sdp;
struct address_space *mapping;
sdp = kzalloc(sizeof(struct gfs2_sbd), GFP_KERNEL);
if (!sdp)
return NULL;
sdp->sd_vfs = sb;
sdp->sd_lkstats = alloc_percpu(struct gfs2_pcpu_lkstats);
if (!sdp->sd_lkstats)
goto fail;
sb->s_fs_info = sdp;
set_bit(SDF_NOJOURNALID, &sdp->sd_flags);
gfs2_tune_init(&sdp->sd_tune);
init_waitqueue_head(&sdp->sd_glock_wait);
init_waitqueue_head(&sdp->sd_async_glock_wait);
atomic_set(&sdp->sd_glock_disposal, 0);
init_completion(&sdp->sd_locking_init);
init_completion(&sdp->sd_wdack);
spin_lock_init(&sdp->sd_statfs_spin);
spin_lock_init(&sdp->sd_rindex_spin);
sdp->sd_rindex_tree.rb_node = NULL;
INIT_LIST_HEAD(&sdp->sd_jindex_list);
spin_lock_init(&sdp->sd_jindex_spin);
mutex_init(&sdp->sd_jindex_mutex);
init_completion(&sdp->sd_journal_ready);
INIT_LIST_HEAD(&sdp->sd_quota_list);
mutex_init(&sdp->sd_quota_mutex);
mutex_init(&sdp->sd_quota_sync_mutex);
init_waitqueue_head(&sdp->sd_quota_wait);
INIT_LIST_HEAD(&sdp->sd_trunc_list);
spin_lock_init(&sdp->sd_trunc_lock);
spin_lock_init(&sdp->sd_bitmap_lock);
mapping = &sdp->sd_aspace;
address_space_init_once(mapping);
mapping->a_ops = &gfs2_rgrp_aops;
mapping->host = sb->s_bdev->bd_inode;
mapping->flags = 0;
mapping_set_gfp_mask(mapping, GFP_NOFS);
mapping->private_data = NULL;
mapping->writeback_index = 0;
spin_lock_init(&sdp->sd_log_lock);
atomic_set(&sdp->sd_log_pinned, 0);
INIT_LIST_HEAD(&sdp->sd_log_revokes);
INIT_LIST_HEAD(&sdp->sd_log_ordered);
spin_lock_init(&sdp->sd_ordered_lock);
init_waitqueue_head(&sdp->sd_log_waitq);
init_waitqueue_head(&sdp->sd_logd_waitq);
spin_lock_init(&sdp->sd_ail_lock);
INIT_LIST_HEAD(&sdp->sd_ail1_list);
INIT_LIST_HEAD(&sdp->sd_ail2_list);
init_rwsem(&sdp->sd_log_flush_lock);
atomic_set(&sdp->sd_log_in_flight, 0);
atomic_set(&sdp->sd_reserving_log, 0);
init_waitqueue_head(&sdp->sd_reserving_log_wait);
init_waitqueue_head(&sdp->sd_log_flush_wait);
atomic_set(&sdp->sd_freeze_state, SFS_UNFROZEN);
mutex_init(&sdp->sd_freeze_mutex);
return sdp;
fail:
free_sbd(sdp);
return NULL;
}
/**
* gfs2_check_sb - Check superblock
* @sdp: the filesystem
* @sb: The superblock
* @silent: Don't print a message if the check fails
*
* Checks the version code of the FS is one that we understand how to
* read and that the sizes of the various on-disk structures have not
* changed.
*/
static int gfs2_check_sb(struct gfs2_sbd *sdp, int silent)
{
struct gfs2_sb_host *sb = &sdp->sd_sb;
if (sb->sb_magic != GFS2_MAGIC ||
sb->sb_type != GFS2_METATYPE_SB) {
if (!silent)
pr_warn("not a GFS2 filesystem\n");
return -EINVAL;
}
/* If format numbers match exactly, we're done. */
if (sb->sb_fs_format == GFS2_FORMAT_FS &&
sb->sb_multihost_format == GFS2_FORMAT_MULTI)
return 0;
fs_warn(sdp, "Unknown on-disk format, unable to mount\n");
return -EINVAL;
}
static void end_bio_io_page(struct bio *bio)
{
struct page *page = bio->bi_private;
if (!bio->bi_status)
SetPageUptodate(page);
else
pr_warn("error %d reading superblock\n", bio->bi_status);
unlock_page(page);
}
static void gfs2_sb_in(struct gfs2_sbd *sdp, const void *buf)
{
struct gfs2_sb_host *sb = &sdp->sd_sb;
struct super_block *s = sdp->sd_vfs;
const struct gfs2_sb *str = buf;
sb->sb_magic = be32_to_cpu(str->sb_header.mh_magic);
sb->sb_type = be32_to_cpu(str->sb_header.mh_type);
sb->sb_format = be32_to_cpu(str->sb_header.mh_format);
sb->sb_fs_format = be32_to_cpu(str->sb_fs_format);
sb->sb_multihost_format = be32_to_cpu(str->sb_multihost_format);
sb->sb_bsize = be32_to_cpu(str->sb_bsize);
sb->sb_bsize_shift = be32_to_cpu(str->sb_bsize_shift);
sb->sb_master_dir.no_addr = be64_to_cpu(str->sb_master_dir.no_addr);
sb->sb_master_dir.no_formal_ino = be64_to_cpu(str->sb_master_dir.no_formal_ino);
sb->sb_root_dir.no_addr = be64_to_cpu(str->sb_root_dir.no_addr);
sb->sb_root_dir.no_formal_ino = be64_to_cpu(str->sb_root_dir.no_formal_ino);
memcpy(sb->sb_lockproto, str->sb_lockproto, GFS2_LOCKNAME_LEN);
memcpy(sb->sb_locktable, str->sb_locktable, GFS2_LOCKNAME_LEN);
memcpy(&s->s_uuid, str->sb_uuid, 16);
}
/**
* gfs2_read_super - Read the gfs2 super block from disk
* @sdp: The GFS2 super block
* @sector: The location of the super block
* @error: The error code to return
*
* This uses the bio functions to read the super block from disk
* because we want to be 100% sure that we never read cached data.
* A super block is read twice only during each GFS2 mount and is
* never written to by the filesystem. The first time its read no
* locks are held, and the only details which are looked at are those
* relating to the locking protocol. Once locking is up and working,
* the sb is read again under the lock to establish the location of
* the master directory (contains pointers to journals etc) and the
* root directory.
*
* Returns: 0 on success or error
*/
static int gfs2_read_super(struct gfs2_sbd *sdp, sector_t sector, int silent)
{
struct super_block *sb = sdp->sd_vfs;
struct gfs2_sb *p;
struct page *page;
struct bio *bio;
page = alloc_page(GFP_NOFS);
if (unlikely(!page))
return -ENOMEM;
ClearPageUptodate(page);
ClearPageDirty(page);
lock_page(page);
bio = bio_alloc(GFP_NOFS, 1);
bio->bi_iter.bi_sector = sector * (sb->s_blocksize >> 9);
bio_set_dev(bio, sb->s_bdev);
bio_add_page(bio, page, PAGE_SIZE, 0);
bio->bi_end_io = end_bio_io_page;
bio->bi_private = page;
bio_set_op_attrs(bio, REQ_OP_READ, REQ_META);
submit_bio(bio);
wait_on_page_locked(page);
bio_put(bio);
if (!PageUptodate(page)) {
__free_page(page);
return -EIO;
}
p = kmap(page);
gfs2_sb_in(sdp, p);
kunmap(page);
__free_page(page);
return gfs2_check_sb(sdp, silent);
}
/**
* gfs2_read_sb - Read super block
* @sdp: The GFS2 superblock
* @silent: Don't print message if mount fails
*
*/
static int gfs2_read_sb(struct gfs2_sbd *sdp, int silent)
{
u32 hash_blocks, ind_blocks, leaf_blocks;
u32 tmp_blocks;
unsigned int x;
int error;
error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift, silent);
if (error) {
if (!silent)
fs_err(sdp, "can't read superblock\n");
return error;
}
sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
GFS2_BASIC_BLOCK_SHIFT;
sdp->sd_fsb2bb = BIT(sdp->sd_fsb2bb_shift);
sdp->sd_diptrs = (sdp->sd_sb.sb_bsize -
sizeof(struct gfs2_dinode)) / sizeof(u64);
sdp->sd_inptrs = (sdp->sd_sb.sb_bsize -
sizeof(struct gfs2_meta_header)) / sizeof(u64);
sdp->sd_jbsize = sdp->sd_sb.sb_bsize - sizeof(struct gfs2_meta_header);
sdp->sd_hash_bsize = sdp->sd_sb.sb_bsize / 2;
sdp->sd_hash_bsize_shift = sdp->sd_sb.sb_bsize_shift - 1;
sdp->sd_hash_ptrs = sdp->sd_hash_bsize / sizeof(u64);
sdp->sd_qc_per_block = (sdp->sd_sb.sb_bsize -
sizeof(struct gfs2_meta_header)) /
sizeof(struct gfs2_quota_change);
sdp->sd_blocks_per_bitmap = (sdp->sd_sb.sb_bsize -
sizeof(struct gfs2_meta_header))
* GFS2_NBBY; /* not the rgrp bitmap, subsequent bitmaps only */
/* Compute maximum reservation required to add a entry to a directory */
hash_blocks = DIV_ROUND_UP(sizeof(u64) * BIT(GFS2_DIR_MAX_DEPTH),
sdp->sd_jbsize);
ind_blocks = 0;
for (tmp_blocks = hash_blocks; tmp_blocks > sdp->sd_diptrs;) {
tmp_blocks = DIV_ROUND_UP(tmp_blocks, sdp->sd_inptrs);
ind_blocks += tmp_blocks;
}
leaf_blocks = 2 + GFS2_DIR_MAX_DEPTH;
sdp->sd_max_dirres = hash_blocks + ind_blocks + leaf_blocks;
sdp->sd_heightsize[0] = sdp->sd_sb.sb_bsize -
sizeof(struct gfs2_dinode);
sdp->sd_heightsize[1] = sdp->sd_sb.sb_bsize * sdp->sd_diptrs;
for (x = 2;; x++) {
u64 space, d;
u32 m;
space = sdp->sd_heightsize[x - 1] * sdp->sd_inptrs;
d = space;
m = do_div(d, sdp->sd_inptrs);
if (d != sdp->sd_heightsize[x - 1] || m)
break;
sdp->sd_heightsize[x] = space;
}
sdp->sd_max_height = x;
sdp->sd_heightsize[x] = ~0;
gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
sdp->sd_max_dents_per_leaf = (sdp->sd_sb.sb_bsize -
sizeof(struct gfs2_leaf)) /
GFS2_MIN_DIRENT_SIZE;
return 0;
}
static int init_names(struct gfs2_sbd *sdp, int silent)
{
char *proto, *table;
int error = 0;
proto = sdp->sd_args.ar_lockproto;
table = sdp->sd_args.ar_locktable;
/* Try to autodetect */
if (!proto[0] || !table[0]) {
error = gfs2_read_super(sdp, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift, silent);
if (error)
return error;
if (!proto[0])
proto = sdp->sd_sb.sb_lockproto;
if (!table[0])
table = sdp->sd_sb.sb_locktable;
}
if (!table[0])
table = sdp->sd_vfs->s_id;
strlcpy(sdp->sd_proto_name, proto, GFS2_FSNAME_LEN);
strlcpy(sdp->sd_table_name, table, GFS2_FSNAME_LEN);
table = sdp->sd_table_name;
while ((table = strchr(table, '/')))
*table = '_';
return error;
}
static int init_locking(struct gfs2_sbd *sdp, struct gfs2_holder *mount_gh,
int undo)
{
int error = 0;
if (undo)
goto fail_trans;
error = gfs2_glock_nq_num(sdp,
GFS2_MOUNT_LOCK, &gfs2_nondisk_glops,
LM_ST_EXCLUSIVE, LM_FLAG_NOEXP | GL_NOCACHE,
mount_gh);
if (error) {
fs_err(sdp, "can't acquire mount glock: %d\n", error);
goto fail;
}
error = gfs2_glock_nq_num(sdp,
GFS2_LIVE_LOCK, &gfs2_nondisk_glops,
LM_ST_SHARED,
LM_FLAG_NOEXP | GL_EXACT,
&sdp->sd_live_gh);
if (error) {
fs_err(sdp, "can't acquire live glock: %d\n", error);
goto fail_mount;
}
error = gfs2_glock_get(sdp, GFS2_RENAME_LOCK, &gfs2_nondisk_glops,
CREATE, &sdp->sd_rename_gl);
if (error) {
fs_err(sdp, "can't create rename glock: %d\n", error);
goto fail_live;
}
error = gfs2_glock_get(sdp, GFS2_FREEZE_LOCK, &gfs2_freeze_glops,
CREATE, &sdp->sd_freeze_gl);
if (error) {
fs_err(sdp, "can't create transaction glock: %d\n", error);
goto fail_rename;
}
return 0;
fail_trans:
gfs2_glock_put(sdp->sd_freeze_gl);
fail_rename:
gfs2_glock_put(sdp->sd_rename_gl);
fail_live:
gfs2_glock_dq_uninit(&sdp->sd_live_gh);
fail_mount:
gfs2_glock_dq_uninit(mount_gh);
fail:
return error;
}
static int gfs2_lookup_root(struct super_block *sb, struct dentry **dptr,
u64 no_addr, const char *name)
{
struct gfs2_sbd *sdp = sb->s_fs_info;
struct dentry *dentry;
struct inode *inode;
inode = gfs2_inode_lookup(sb, DT_DIR, no_addr, 0,
GFS2_BLKST_FREE /* ignore */);
if (IS_ERR(inode)) {
fs_err(sdp, "can't read in %s inode: %ld\n", name, PTR_ERR(inode));
return PTR_ERR(inode);
}
dentry = d_make_root(inode);
if (!dentry) {
fs_err(sdp, "can't alloc %s dentry\n", name);
return -ENOMEM;
}
*dptr = dentry;
return 0;
}
static int init_sb(struct gfs2_sbd *sdp, int silent)
{
struct super_block *sb = sdp->sd_vfs;
struct gfs2_holder sb_gh;
u64 no_addr;
int ret;
ret = gfs2_glock_nq_num(sdp, GFS2_SB_LOCK, &gfs2_meta_glops,
LM_ST_SHARED, 0, &sb_gh);
if (ret) {
fs_err(sdp, "can't acquire superblock glock: %d\n", ret);
return ret;
}
ret = gfs2_read_sb(sdp, silent);
if (ret) {
fs_err(sdp, "can't read superblock: %d\n", ret);
goto out;
}
/* Set up the buffer cache and SB for real */
if (sdp->sd_sb.sb_bsize < bdev_logical_block_size(sb->s_bdev)) {
ret = -EINVAL;
fs_err(sdp, "FS block size (%u) is too small for device "
"block size (%u)\n",
sdp->sd_sb.sb_bsize, bdev_logical_block_size(sb->s_bdev));
goto out;
}
if (sdp->sd_sb.sb_bsize > PAGE_SIZE) {
ret = -EINVAL;
fs_err(sdp, "FS block size (%u) is too big for machine "
"page size (%u)\n",
sdp->sd_sb.sb_bsize, (unsigned int)PAGE_SIZE);
goto out;
}
sb_set_blocksize(sb, sdp->sd_sb.sb_bsize);
/* Get the root inode */
no_addr = sdp->sd_sb.sb_root_dir.no_addr;
ret = gfs2_lookup_root(sb, &sdp->sd_root_dir, no_addr, "root");
if (ret)
goto out;
/* Get the master inode */
no_addr = sdp->sd_sb.sb_master_dir.no_addr;
ret = gfs2_lookup_root(sb, &sdp->sd_master_dir, no_addr, "master");
if (ret) {
dput(sdp->sd_root_dir);
goto out;
}
sb->s_root = dget(sdp->sd_args.ar_meta ? sdp->sd_master_dir : sdp->sd_root_dir);
out:
gfs2_glock_dq_uninit(&sb_gh);
return ret;
}
static void gfs2_others_may_mount(struct gfs2_sbd *sdp)
{
char *message = "FIRSTMOUNT=Done";
char *envp[] = { message, NULL };
fs_info(sdp, "first mount done, others may mount\n");
if (sdp->sd_lockstruct.ls_ops->lm_first_done)
sdp->sd_lockstruct.ls_ops->lm_first_done(sdp);
kobject_uevent_env(&sdp->sd_kobj, KOBJ_CHANGE, envp);
}
/**
* gfs2_jindex_hold - Grab a lock on the jindex
* @sdp: The GFS2 superblock
* @ji_gh: the holder for the jindex glock
*
* Returns: errno
*/
static int gfs2_jindex_hold(struct gfs2_sbd *sdp, struct gfs2_holder *ji_gh)
{
struct gfs2_inode *dip = GFS2_I(sdp->sd_jindex);
struct qstr name;
char buf[20];
struct gfs2_jdesc *jd;
int error;
name.name = buf;
mutex_lock(&sdp->sd_jindex_mutex);
for (;;) {
error = gfs2_glock_nq_init(dip->i_gl, LM_ST_SHARED, 0, ji_gh);
if (error)
break;
name.len = sprintf(buf, "journal%u", sdp->sd_journals);
name.hash = gfs2_disk_hash(name.name, name.len);
error = gfs2_dir_check(sdp->sd_jindex, &name, NULL);
if (error == -ENOENT) {
error = 0;
break;
}
gfs2_glock_dq_uninit(ji_gh);
if (error)
break;
error = -ENOMEM;
jd = kzalloc(sizeof(struct gfs2_jdesc), GFP_KERNEL);
if (!jd)
break;
INIT_LIST_HEAD(&jd->extent_list);
INIT_LIST_HEAD(&jd->jd_revoke_list);
INIT_WORK(&jd->jd_work, gfs2_recover_func);
jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1);
if (IS_ERR_OR_NULL(jd->jd_inode)) {
if (!jd->jd_inode)
error = -ENOENT;
else
error = PTR_ERR(jd->jd_inode);
kfree(jd);
break;
}
spin_lock(&sdp->sd_jindex_spin);
jd->jd_jid = sdp->sd_journals++;
list_add_tail(&jd->jd_list, &sdp->sd_jindex_list);
spin_unlock(&sdp->sd_jindex_spin);
}
mutex_unlock(&sdp->sd_jindex_mutex);
return error;
}
/**
* check_journal_clean - Make sure a journal is clean for a spectator mount
* @sdp: The GFS2 superblock
* @jd: The journal descriptor
*
* Returns: 0 if the journal is clean or locked, else an error
*/
static int check_journal_clean(struct gfs2_sbd *sdp, struct gfs2_jdesc *jd)
{
int error;
struct gfs2_holder j_gh;
struct gfs2_log_header_host head;
struct gfs2_inode *ip;
ip = GFS2_I(jd->jd_inode);
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_NOEXP |
GL_EXACT | GL_NOCACHE, &j_gh);
if (error) {
fs_err(sdp, "Error locking journal for spectator mount.\n");
return -EPERM;
}
error = gfs2_jdesc_check(jd);
if (error) {
fs_err(sdp, "Error checking journal for spectator mount.\n");
goto out_unlock;
}
error = gfs2_find_jhead(jd, &head, false);
if (error) {
fs_err(sdp, "Error parsing journal for spectator mount.\n");
goto out_unlock;
}
if (!(head.lh_flags & GFS2_LOG_HEAD_UNMOUNT)) {
error = -EPERM;
fs_err(sdp, "jid=%u: Journal is dirty, so the first mounter "
"must not be a spectator.\n", jd->jd_jid);
}
out_unlock:
gfs2_glock_dq_uninit(&j_gh);
return error;
}
static int init_journal(struct gfs2_sbd *sdp, int undo)
{
struct inode *master = d_inode(sdp->sd_master_dir);
struct gfs2_holder ji_gh;
struct gfs2_inode *ip;
int jindex = 1;
int error = 0;
if (undo) {
jindex = 0;
goto fail_jinode_gh;
}
sdp->sd_jindex = gfs2_lookup_simple(master, "jindex");
if (IS_ERR(sdp->sd_jindex)) {
fs_err(sdp, "can't lookup journal index: %d\n", error);
return PTR_ERR(sdp->sd_jindex);
}
/* Load in the journal index special file */
error = gfs2_jindex_hold(sdp, &ji_gh);
if (error) {
fs_err(sdp, "can't read journal index: %d\n", error);
goto fail;
}
error = -EUSERS;
if (!gfs2_jindex_size(sdp)) {
fs_err(sdp, "no journals!\n");
goto fail_jindex;
}
atomic_set(&sdp->sd_log_blks_needed, 0);
if (sdp->sd_args.ar_spectator) {
sdp->sd_jdesc = gfs2_jdesc_find(sdp, 0);
atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
} else {
if (sdp->sd_lockstruct.ls_jid >= gfs2_jindex_size(sdp)) {
fs_err(sdp, "can't mount journal #%u\n",
sdp->sd_lockstruct.ls_jid);
fs_err(sdp, "there are only %u journals (0 - %u)\n",
gfs2_jindex_size(sdp),
gfs2_jindex_size(sdp) - 1);
goto fail_jindex;
}
sdp->sd_jdesc = gfs2_jdesc_find(sdp, sdp->sd_lockstruct.ls_jid);
error = gfs2_glock_nq_num(sdp, sdp->sd_lockstruct.ls_jid,
&gfs2_journal_glops,
LM_ST_EXCLUSIVE, LM_FLAG_NOEXP,
&sdp->sd_journal_gh);
if (error) {
fs_err(sdp, "can't acquire journal glock: %d\n", error);
goto fail_jindex;
}
ip = GFS2_I(sdp->sd_jdesc->jd_inode);
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED,
LM_FLAG_NOEXP | GL_EXACT | GL_NOCACHE,
&sdp->sd_jinode_gh);
if (error) {
fs_err(sdp, "can't acquire journal inode glock: %d\n",
error);
goto fail_journal_gh;
}
error = gfs2_jdesc_check(sdp->sd_jdesc);
if (error) {
fs_err(sdp, "my journal (%u) is bad: %d\n",
sdp->sd_jdesc->jd_jid, error);
goto fail_jinode_gh;
}
atomic_set(&sdp->sd_log_blks_free, sdp->sd_jdesc->jd_blocks);
atomic_set(&sdp->sd_log_thresh1, 2*sdp->sd_jdesc->jd_blocks/5);
atomic_set(&sdp->sd_log_thresh2, 4*sdp->sd_jdesc->jd_blocks/5);
/* Map the extents for this journal's blocks */
gfs2_map_journal_extents(sdp, sdp->sd_jdesc);
}
trace_gfs2_log_blocks(sdp, atomic_read(&sdp->sd_log_blks_free));
if (sdp->sd_lockstruct.ls_first) {
unsigned int x;
for (x = 0; x < sdp->sd_journals; x++) {
struct gfs2_jdesc *jd = gfs2_jdesc_find(sdp, x);
if (sdp->sd_args.ar_spectator) {
error = check_journal_clean(sdp, jd);
if (error)
goto fail_jinode_gh;
continue;
}
error = gfs2_recover_journal(jd, true);
if (error) {
fs_err(sdp, "error recovering journal %u: %d\n",
x, error);
goto fail_jinode_gh;
}
}
gfs2_others_may_mount(sdp);
} else if (!sdp->sd_args.ar_spectator) {
error = gfs2_recover_journal(sdp->sd_jdesc, true);
if (error) {
fs_err(sdp, "error recovering my journal: %d\n", error);
goto fail_jinode_gh;
}
}
sdp->sd_log_idle = 1;
set_bit(SDF_JOURNAL_CHECKED, &sdp->sd_flags);
gfs2_glock_dq_uninit(&ji_gh);
jindex = 0;
INIT_WORK(&sdp->sd_freeze_work, gfs2_freeze_func);
return 0;
fail_jinode_gh:
if (!sdp->sd_args.ar_spectator)
gfs2_glock_dq_uninit(&sdp->sd_jinode_gh);
fail_journal_gh:
if (!sdp->sd_args.ar_spectator)
gfs2_glock_dq_uninit(&sdp->sd_journal_gh);
fail_jindex:
gfs2_jindex_free(sdp);
if (jindex)
gfs2_glock_dq_uninit(&ji_gh);
fail:
iput(sdp->sd_jindex);
return error;
}
static struct lock_class_key gfs2_quota_imutex_key;
static int init_inodes(struct gfs2_sbd *sdp, int undo)
{
int error = 0;
struct inode *master = d_inode(sdp->sd_master_dir);
if (undo)
goto fail_qinode;
error = init_journal(sdp, undo);
complete_all(&sdp->sd_journal_ready);
if (error)
goto fail;
/* Read in the master statfs inode */
sdp->sd_statfs_inode = gfs2_lookup_simple(master, "statfs");
if (IS_ERR(sdp->sd_statfs_inode)) {
error = PTR_ERR(sdp->sd_statfs_inode);
fs_err(sdp, "can't read in statfs inode: %d\n", error);
goto fail_journal;
}
/* Read in the resource index inode */
sdp->sd_rindex = gfs2_lookup_simple(master, "rindex");
if (IS_ERR(sdp->sd_rindex)) {
error = PTR_ERR(sdp->sd_rindex);
fs_err(sdp, "can't get resource index inode: %d\n", error);
goto fail_statfs;
}
sdp->sd_rindex_uptodate = 0;
/* Read in the quota inode */
sdp->sd_quota_inode = gfs2_lookup_simple(master, "quota");
if (IS_ERR(sdp->sd_quota_inode)) {
error = PTR_ERR(sdp->sd_quota_inode);
fs_err(sdp, "can't get quota file inode: %d\n", error);
goto fail_rindex;
}
/*
* i_rwsem on quota files is special. Since this inode is hidden system
* file, we are safe to define locking ourselves.
*/
lockdep_set_class(&sdp->sd_quota_inode->i_rwsem,
&gfs2_quota_imutex_key);
error = gfs2_rindex_update(sdp);
if (error)
goto fail_qinode;
return 0;
fail_qinode:
iput(sdp->sd_quota_inode);
fail_rindex:
gfs2_clear_rgrpd(sdp);
iput(sdp->sd_rindex);
fail_statfs:
iput(sdp->sd_statfs_inode);
fail_journal:
init_journal(sdp, UNDO);
fail:
return error;
}
static int init_per_node(struct gfs2_sbd *sdp, int undo)
{
struct inode *pn = NULL;
char buf[30];
int error = 0;
struct gfs2_inode *ip;
struct inode *master = d_inode(sdp->sd_master_dir);
if (sdp->sd_args.ar_spectator)
return 0;
if (undo)
goto fail_qc_gh;
pn = gfs2_lookup_simple(master, "per_node");
if (IS_ERR(pn)) {
error = PTR_ERR(pn);
fs_err(sdp, "can't find per_node directory: %d\n", error);
return error;
}
sprintf(buf, "statfs_change%u", sdp->sd_jdesc->jd_jid);
sdp->sd_sc_inode = gfs2_lookup_simple(pn, buf);
if (IS_ERR(sdp->sd_sc_inode)) {
error = PTR_ERR(sdp->sd_sc_inode);
fs_err(sdp, "can't find local \"sc\" file: %d\n", error);
goto fail;
}
sprintf(buf, "quota_change%u", sdp->sd_jdesc->jd_jid);
sdp->sd_qc_inode = gfs2_lookup_simple(pn, buf);
if (IS_ERR(sdp->sd_qc_inode)) {
error = PTR_ERR(sdp->sd_qc_inode);
fs_err(sdp, "can't find local \"qc\" file: %d\n", error);
goto fail_ut_i;
}
iput(pn);
pn = NULL;
ip = GFS2_I(sdp->sd_sc_inode);
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
&sdp->sd_sc_gh);
if (error) {
fs_err(sdp, "can't lock local \"sc\" file: %d\n", error);
goto fail_qc_i;
}
ip = GFS2_I(sdp->sd_qc_inode);
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0,
&sdp->sd_qc_gh);
if (error) {
fs_err(sdp, "can't lock local \"qc\" file: %d\n", error);
goto fail_ut_gh;
}
return 0;
fail_qc_gh:
gfs2_glock_dq_uninit(&sdp->sd_qc_gh);
fail_ut_gh:
gfs2_glock_dq_uninit(&sdp->sd_sc_gh);
fail_qc_i:
iput(sdp->sd_qc_inode);
fail_ut_i:
iput(sdp->sd_sc_inode);
fail:
iput(pn);
return error;
}
static const match_table_t nolock_tokens = {
{ Opt_jid, "jid=%d\n", },
{ Opt_err, NULL },
};
static const struct lm_lockops nolock_ops = {
.lm_proto_name = "lock_nolock",
.lm_put_lock = gfs2_glock_free,
.lm_tokens = &nolock_tokens,
};
/**
* gfs2_lm_mount - mount a locking protocol
* @sdp: the filesystem
* @args: mount arguments
* @silent: if 1, don't complain if the FS isn't a GFS2 fs
*
* Returns: errno
*/
static int gfs2_lm_mount(struct gfs2_sbd *sdp, int silent)
{
const struct lm_lockops *lm;
struct lm_lockstruct *ls = &sdp->sd_lockstruct;
struct gfs2_args *args = &sdp->sd_args;
const char *proto = sdp->sd_proto_name;
const char *table = sdp->sd_table_name;
char *o, *options;
int ret;
if (!strcmp("lock_nolock", proto)) {
lm = &nolock_ops;
sdp->sd_args.ar_localflocks = 1;
#ifdef CONFIG_GFS2_FS_LOCKING_DLM
} else if (!strcmp("lock_dlm", proto)) {
lm = &gfs2_dlm_ops;
#endif
} else {
pr_info("can't find protocol %s\n", proto);
return -ENOENT;
}
fs_info(sdp, "Trying to join cluster \"%s\", \"%s\"\n", proto, table);
ls->ls_ops = lm;
ls->ls_first = 1;
for (options = args->ar_hostdata; (o = strsep(&options, ":")); ) {
substring_t tmp[MAX_OPT_ARGS];
int token, option;
if (!o || !*o)
continue;
token = match_token(o, *lm->lm_tokens, tmp);
switch (token) {
case Opt_jid:
ret = match_int(&tmp[0], &option);
if (ret || option < 0)
goto hostdata_error;
if (test_and_clear_bit(SDF_NOJOURNALID, &sdp->sd_flags))
ls->ls_jid = option;
break;
case Opt_id:
case Opt_nodir:
/* Obsolete, but left for backward compat purposes */
break;
case Opt_first:
ret = match_int(&tmp[0], &option);
if (ret || (option != 0 && option != 1))
goto hostdata_error;
ls->ls_first = option;
break;
case Opt_err:
default:
hostdata_error:
fs_info(sdp, "unknown hostdata (%s)\n", o);
return -EINVAL;
}
}
if (lm->lm_mount == NULL) {
fs_info(sdp, "Now mounting FS...\n");
complete_all(&sdp->sd_locking_init);
return 0;
}
ret = lm->lm_mount(sdp, table);
if (ret == 0)
fs_info(sdp, "Joined cluster. Now mounting FS...\n");
complete_all(&sdp->sd_locking_init);
return ret;
}
void gfs2_lm_unmount(struct gfs2_sbd *sdp)
{
const struct lm_lockops *lm = sdp->sd_lockstruct.ls_ops;
if (likely(!test_bit(SDF_WITHDRAWN, &sdp->sd_flags)) &&
lm->lm_unmount)
lm->lm_unmount(sdp);
}
static int wait_on_journal(struct gfs2_sbd *sdp)
{
if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL)
return 0;
return wait_on_bit(&sdp->sd_flags, SDF_NOJOURNALID, TASK_INTERRUPTIBLE)
? -EINTR : 0;
}
void gfs2_online_uevent(struct gfs2_sbd *sdp)
{
struct super_block *sb = sdp->sd_vfs;
char ro[20];
char spectator[20];
char *envp[] = { ro, spectator, NULL };
sprintf(ro, "RDONLY=%d", sb_rdonly(sb));
sprintf(spectator, "SPECTATOR=%d", sdp->sd_args.ar_spectator ? 1 : 0);
kobject_uevent_env(&sdp->sd_kobj, KOBJ_ONLINE, envp);
}
/**
* fill_super - Read in superblock
* @sb: The VFS superblock
* @data: Mount options
* @silent: Don't complain if it's not a GFS2 filesystem
*
* Returns: errno
*/
static int fill_super(struct super_block *sb, struct gfs2_args *args, int silent)
{
struct gfs2_sbd *sdp;
struct gfs2_holder mount_gh;
int error;
sdp = init_sbd(sb);
if (!sdp) {
pr_warn("can't alloc struct gfs2_sbd\n");
return -ENOMEM;
}
sdp->sd_args = *args;
if (sdp->sd_args.ar_spectator) {
sb->s_flags |= SB_RDONLY;
set_bit(SDF_RORECOVERY, &sdp->sd_flags);
}
if (sdp->sd_args.ar_posix_acl)
sb->s_flags |= SB_POSIXACL;
if (sdp->sd_args.ar_nobarrier)
set_bit(SDF_NOBARRIERS, &sdp->sd_flags);
sb->s_flags |= SB_NOSEC;
sb->s_magic = GFS2_MAGIC;
sb->s_op = &gfs2_super_ops;
sb->s_d_op = &gfs2_dops;
sb->s_export_op = &gfs2_export_ops;
sb->s_xattr = gfs2_xattr_handlers;
sb->s_qcop = &gfs2_quotactl_ops;
sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP;
sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
sb->s_time_gran = 1;
sb->s_maxbytes = MAX_LFS_FILESIZE;
/* Set up the buffer cache and fill in some fake block size values
to allow us to read-in the on-disk superblock. */
sdp->sd_sb.sb_bsize = sb_min_blocksize(sb, GFS2_BASIC_BLOCK);
sdp->sd_sb.sb_bsize_shift = sb->s_blocksize_bits;
sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
GFS2_BASIC_BLOCK_SHIFT;
sdp->sd_fsb2bb = BIT(sdp->sd_fsb2bb_shift);
sdp->sd_tune.gt_logd_secs = sdp->sd_args.ar_commit;
sdp->sd_tune.gt_quota_quantum = sdp->sd_args.ar_quota_quantum;
if (sdp->sd_args.ar_statfs_quantum) {
sdp->sd_tune.gt_statfs_slow = 0;
sdp->sd_tune.gt_statfs_quantum = sdp->sd_args.ar_statfs_quantum;
} else {
sdp->sd_tune.gt_statfs_slow = 1;
sdp->sd_tune.gt_statfs_quantum = 30;
}
error = init_names(sdp, silent);
if (error) {
/* In this case, we haven't initialized sysfs, so we have to
manually free the sdp. */
free_sbd(sdp);
sb->s_fs_info = NULL;
return error;
}
snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s", sdp->sd_table_name);
error = gfs2_sys_fs_add(sdp);
/*
* If we hit an error here, gfs2_sys_fs_add will have called function
* kobject_put which causes the sysfs usage count to go to zero, which
* causes sysfs to call function gfs2_sbd_release, which frees sdp.
* Subsequent error paths here will call gfs2_sys_fs_del, which also
* kobject_put to free sdp.
*/
if (error)
return error;
gfs2_create_debugfs_file(sdp);
error = gfs2_lm_mount(sdp, silent);
if (error)
goto fail_debug;
error = init_locking(sdp, &mount_gh, DO);
if (error)
goto fail_lm;
error = init_sb(sdp, silent);
if (error)
goto fail_locking;
error = wait_on_journal(sdp);
if (error)
goto fail_sb;
/*
* If user space has failed to join the cluster or some similar
* failure has occurred, then the journal id will contain a
* negative (error) number. This will then be returned to the
* caller (of the mount syscall). We do this even for spectator
* mounts (which just write a jid of 0 to indicate "ok" even though
* the jid is unused in the spectator case)
*/
if (sdp->sd_lockstruct.ls_jid < 0) {
error = sdp->sd_lockstruct.ls_jid;
sdp->sd_lockstruct.ls_jid = 0;
goto fail_sb;
}
if (sdp->sd_args.ar_spectator)
snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s.s",
sdp->sd_table_name);
else
snprintf(sdp->sd_fsname, sizeof(sdp->sd_fsname), "%s.%u",
sdp->sd_table_name, sdp->sd_lockstruct.ls_jid);
error = init_inodes(sdp, DO);
if (error)
goto fail_sb;
error = init_per_node(sdp, DO);
if (error)
goto fail_inodes;
error = gfs2_statfs_init(sdp);
if (error) {
fs_err(sdp, "can't initialize statfs subsystem: %d\n", error);
goto fail_per_node;
}
if (!sb_rdonly(sb)) {
error = gfs2_make_fs_rw(sdp);
if (error) {
fs_err(sdp, "can't make FS RW: %d\n", error);
goto fail_per_node;
}
}
gfs2_glock_dq_uninit(&mount_gh);
gfs2_online_uevent(sdp);
return 0;
fail_per_node:
init_per_node(sdp, UNDO);
fail_inodes:
init_inodes(sdp, UNDO);
fail_sb:
if (sdp->sd_root_dir)
dput(sdp->sd_root_dir);
if (sdp->sd_master_dir)
dput(sdp->sd_master_dir);
if (sb->s_root)
dput(sb->s_root);
sb->s_root = NULL;
fail_locking:
init_locking(sdp, &mount_gh, UNDO);
fail_lm:
complete_all(&sdp->sd_journal_ready);
gfs2_gl_hash_clear(sdp);
gfs2_lm_unmount(sdp);
fail_debug:
gfs2_delete_debugfs_file(sdp);
/* gfs2_sys_fs_del must be the last thing we do, since it causes
* sysfs to call function gfs2_sbd_release, which frees sdp. */
gfs2_sys_fs_del(sdp);
sb->s_fs_info = NULL;
return error;
}
static int set_gfs2_super(struct super_block *s, void *data)
{
s->s_bdev = data;
s->s_dev = s->s_bdev->bd_dev;
s->s_bdi = bdi_get(s->s_bdev->bd_bdi);
return 0;
}
static int test_gfs2_super(struct super_block *s, void *ptr)
{
struct block_device *bdev = ptr;
return (bdev == s->s_bdev);
}
/**
* gfs2_mount - Get the GFS2 superblock
* @fs_type: The GFS2 filesystem type
* @flags: Mount flags
* @dev_name: The name of the device
* @data: The mount arguments
*
* Q. Why not use get_sb_bdev() ?
* A. We need to select one of two root directories to mount, independent
* of whether this is the initial, or subsequent, mount of this sb
*
* Returns: 0 or -ve on error
*/
static struct dentry *gfs2_mount(struct file_system_type *fs_type, int flags,
const char *dev_name, void *data)
{
struct block_device *bdev;
struct super_block *s;
fmode_t mode = FMODE_READ | FMODE_EXCL;
int error;
struct gfs2_args args;
struct gfs2_sbd *sdp;
if (!(flags & SB_RDONLY))
mode |= FMODE_WRITE;
bdev = blkdev_get_by_path(dev_name, mode, fs_type);
if (IS_ERR(bdev))
return ERR_CAST(bdev);
/*
* once the super is inserted into the list by sget, s_umount
* will protect the lockfs code from trying to start a snapshot
* while we are mounting
*/
mutex_lock(&bdev->bd_fsfreeze_mutex);
if (bdev->bd_fsfreeze_count > 0) {
mutex_unlock(&bdev->bd_fsfreeze_mutex);
error = -EBUSY;
goto error_bdev;
}
s = sget(fs_type, test_gfs2_super, set_gfs2_super, flags, bdev);
mutex_unlock(&bdev->bd_fsfreeze_mutex);
error = PTR_ERR(s);
if (IS_ERR(s))
goto error_bdev;
if (s->s_root) {
/*
* s_umount nests inside bd_mutex during
* __invalidate_device(). blkdev_put() acquires
* bd_mutex and can't be called under s_umount. Drop
* s_umount temporarily. This is safe as we're
* holding an active reference.
*/
up_write(&s->s_umount);
blkdev_put(bdev, mode);
down_write(&s->s_umount);
} else {
/* s_mode must be set before deactivate_locked_super calls */
s->s_mode = mode;
}
memset(&args, 0, sizeof(args));
args.ar_quota = GFS2_QUOTA_DEFAULT;
args.ar_data = GFS2_DATA_DEFAULT;
args.ar_commit = 30;
args.ar_statfs_quantum = 30;
args.ar_quota_quantum = 60;
args.ar_errors = GFS2_ERRORS_DEFAULT;
error = gfs2_mount_args(&args, data);
if (error) {
pr_warn("can't parse mount arguments\n");
goto error_super;
}
if (s->s_root) {
error = -EBUSY;
if ((flags ^ s->s_flags) & SB_RDONLY)
goto error_super;
} else {
snprintf(s->s_id, sizeof(s->s_id), "%pg", bdev);
sb_set_blocksize(s, block_size(bdev));
error = fill_super(s, &args, flags & SB_SILENT ? 1 : 0);
if (error)
goto error_super;
s->s_flags |= SB_ACTIVE;
bdev->bd_super = s;
}
sdp = s->s_fs_info;
if (args.ar_meta)
return dget(sdp->sd_master_dir);
else
return dget(sdp->sd_root_dir);
error_super:
deactivate_locked_super(s);
return ERR_PTR(error);
error_bdev:
blkdev_put(bdev, mode);
return ERR_PTR(error);
}
static int set_meta_super(struct super_block *s, void *ptr)
{
return -EINVAL;
}
static struct dentry *gfs2_mount_meta(struct file_system_type *fs_type,
int flags, const char *dev_name, void *data)
{
struct super_block *s;
struct gfs2_sbd *sdp;
struct path path;
int error;
if (!dev_name || !*dev_name)
return ERR_PTR(-EINVAL);
error = kern_path(dev_name, LOOKUP_FOLLOW, &path);
if (error) {
pr_warn("path_lookup on %s returned error %d\n",
dev_name, error);
return ERR_PTR(error);
}
s = sget(&gfs2_fs_type, test_gfs2_super, set_meta_super, flags,
path.dentry->d_sb->s_bdev);
path_put(&path);
if (IS_ERR(s)) {
pr_warn("gfs2 mount does not exist\n");
return ERR_CAST(s);
}
if ((flags ^ s->s_flags) & SB_RDONLY) {
deactivate_locked_super(s);
return ERR_PTR(-EBUSY);
}
sdp = s->s_fs_info;
return dget(sdp->sd_master_dir);
}
static void gfs2_kill_sb(struct super_block *sb)
{
struct gfs2_sbd *sdp = sb->s_fs_info;
if (sdp == NULL) {
kill_block_super(sb);
return;
}
gfs2_log_flush(sdp, NULL, GFS2_LOG_HEAD_FLUSH_SYNC | GFS2_LFC_KILL_SB);
dput(sdp->sd_root_dir);
dput(sdp->sd_master_dir);
sdp->sd_root_dir = NULL;
sdp->sd_master_dir = NULL;
shrink_dcache_sb(sb);
kill_block_super(sb);
}
struct file_system_type gfs2_fs_type = {
.name = "gfs2",
.fs_flags = FS_REQUIRES_DEV,
.mount = gfs2_mount,
.kill_sb = gfs2_kill_sb,
.owner = THIS_MODULE,
};
MODULE_ALIAS_FS("gfs2");
struct file_system_type gfs2meta_fs_type = {
.name = "gfs2meta",
.fs_flags = FS_REQUIRES_DEV,
.mount = gfs2_mount_meta,
.owner = THIS_MODULE,
};
MODULE_ALIAS_FS("gfs2meta");