aha/fs/gfs2/super.c
Steven Whitehouse 3699e3a44b [GFS2] Clean up/speed up readdir
This removes the extra filldir callback which gfs2 was using to
enclose an attempt at readahead for inodes during readdir. The
code was too complicated and also hurts performance badly in the
case that the getdents64/readdir call isn't being followed by
stat() and it wasn't even getting it right all the time when it
was.

As a result, on my test box an "ls" of a directory containing 250000
files fell from about 7mins (freshly mounted, so nothing cached) to
between about 15 to 25 seconds. When the directory content was cached,
the time taken fell from about 3mins to about 4 or 5 seconds.

Interestingly in the cached case, running "ls -l" once reduced the time
taken for subsequent runs of "ls" to about 6 secs even without this
patch. Now it turns out that there was a special case of glocks being
used for prefetching the metadata, but because of the timeouts for these
locks (set to 10 secs) the metadata was being timed out before it was
being used and this the prefetch code was constantly trying to prefetch
the same data over and over.

Calling "ls -l" meant that the inodes were brought into memory and once
the inodes are cached, the glocks are not disposed of until the inodes
are pushed out of the cache, thus extending the lifetime of the glocks,
and thus bringing down the time for subsequent runs of "ls"
considerably.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2007-02-05 13:37:04 -05:00

993 lines
23 KiB
C

/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License version 2.
*/
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/crc32.h>
#include <linux/gfs2_ondisk.h>
#include <linux/bio.h>
#include <linux/lm_interface.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"
static const u32 gfs2_old_fs_formats[] = {
0
};
static const u32 gfs2_old_multihost_formats[] = {
0
};
/**
* gfs2_tune_init - Fill a gfs2_tune structure with default values
* @gt: tune
*
*/
void gfs2_tune_init(struct gfs2_tune *gt)
{
spin_lock_init(&gt->gt_spin);
gt->gt_ilimit = 100;
gt->gt_ilimit_tries = 3;
gt->gt_ilimit_min = 1;
gt->gt_demote_secs = 300;
gt->gt_incore_log_blocks = 1024;
gt->gt_log_flush_secs = 60;
gt->gt_jindex_refresh_secs = 60;
gt->gt_scand_secs = 15;
gt->gt_recoverd_secs = 60;
gt->gt_logd_secs = 1;
gt->gt_quotad_secs = 5;
gt->gt_quota_simul_sync = 64;
gt->gt_quota_warn_period = 10;
gt->gt_quota_scale_num = 1;
gt->gt_quota_scale_den = 1;
gt->gt_quota_cache_secs = 300;
gt->gt_quota_quantum = 60;
gt->gt_atime_quantum = 3600;
gt->gt_new_files_jdata = 0;
gt->gt_new_files_directio = 0;
gt->gt_max_atomic_write = 4 << 20;
gt->gt_max_readahead = 1 << 18;
gt->gt_lockdump_size = 131072;
gt->gt_stall_secs = 600;
gt->gt_complain_secs = 10;
gt->gt_reclaim_limit = 5000;
gt->gt_entries_per_readdir = 32;
gt->gt_greedy_default = HZ / 10;
gt->gt_greedy_quantum = HZ / 40;
gt->gt_greedy_max = HZ / 4;
gt->gt_statfs_quantum = 30;
gt->gt_statfs_slow = 0;
}
/**
* 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.
*/
int gfs2_check_sb(struct gfs2_sbd *sdp, struct gfs2_sb_host *sb, int silent)
{
unsigned int x;
if (sb->sb_header.mh_magic != GFS2_MAGIC ||
sb->sb_header.mh_type != GFS2_METATYPE_SB) {
if (!silent)
printk(KERN_WARNING "GFS2: 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;
if (sb->sb_fs_format != GFS2_FORMAT_FS) {
for (x = 0; gfs2_old_fs_formats[x]; x++)
if (gfs2_old_fs_formats[x] == sb->sb_fs_format)
break;
if (!gfs2_old_fs_formats[x]) {
printk(KERN_WARNING
"GFS2: code version (%u, %u) is incompatible "
"with ondisk format (%u, %u)\n",
GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
sb->sb_fs_format, sb->sb_multihost_format);
printk(KERN_WARNING
"GFS2: I don't know how to upgrade this FS\n");
return -EINVAL;
}
}
if (sb->sb_multihost_format != GFS2_FORMAT_MULTI) {
for (x = 0; gfs2_old_multihost_formats[x]; x++)
if (gfs2_old_multihost_formats[x] ==
sb->sb_multihost_format)
break;
if (!gfs2_old_multihost_formats[x]) {
printk(KERN_WARNING
"GFS2: code version (%u, %u) is incompatible "
"with ondisk format (%u, %u)\n",
GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
sb->sb_fs_format, sb->sb_multihost_format);
printk(KERN_WARNING
"GFS2: I don't know how to upgrade this FS\n");
return -EINVAL;
}
}
if (!sdp->sd_args.ar_upgrade) {
printk(KERN_WARNING
"GFS2: code version (%u, %u) is incompatible "
"with ondisk format (%u, %u)\n",
GFS2_FORMAT_FS, GFS2_FORMAT_MULTI,
sb->sb_fs_format, sb->sb_multihost_format);
printk(KERN_INFO
"GFS2: Use the \"upgrade\" mount option to upgrade "
"the FS\n");
printk(KERN_INFO "GFS2: See the manual for more details\n");
return -EINVAL;
}
return 0;
}
static int end_bio_io_page(struct bio *bio, unsigned int bytes_done, int error)
{
struct page *page = bio->bi_private;
if (bio->bi_size)
return 1;
if (!error)
SetPageUptodate(page);
else
printk(KERN_WARNING "gfs2: error %d reading superblock\n", error);
unlock_page(page);
return 0;
}
/**
* gfs2_read_super - Read the gfs2 super block from disk
* @sb: The VFS super block
* @sector: The location of the super block
*
* 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: A page containing the sb or NULL
*/
struct page *gfs2_read_super(struct super_block *sb, sector_t sector)
{
struct page *page;
struct bio *bio;
page = alloc_page(GFP_KERNEL);
if (unlikely(!page))
return NULL;
ClearPageUptodate(page);
ClearPageDirty(page);
lock_page(page);
bio = bio_alloc(GFP_KERNEL, 1);
if (unlikely(!bio)) {
__free_page(page);
return NULL;
}
bio->bi_sector = sector * (sb->s_blocksize >> 9);
bio->bi_bdev = sb->s_bdev;
bio_add_page(bio, page, PAGE_SIZE, 0);
bio->bi_end_io = end_bio_io_page;
bio->bi_private = page;
submit_bio(READ_SYNC | (1 << BIO_RW_META), bio);
wait_on_page_locked(page);
bio_put(bio);
if (!PageUptodate(page)) {
__free_page(page);
return NULL;
}
return page;
}
/**
* gfs2_read_sb - Read super block
* @sdp: The GFS2 superblock
* @gl: the glock for the superblock (assumed to be held)
* @silent: Don't print message if mount fails
*
*/
int gfs2_read_sb(struct gfs2_sbd *sdp, struct gfs2_glock *gl, int silent)
{
u32 hash_blocks, ind_blocks, leaf_blocks;
u32 tmp_blocks;
unsigned int x;
int error;
struct page *page;
char *sb;
page = gfs2_read_super(sdp->sd_vfs, GFS2_SB_ADDR >> sdp->sd_fsb2bb_shift);
if (!page) {
if (!silent)
fs_err(sdp, "can't read superblock\n");
return -EIO;
}
sb = kmap(page);
gfs2_sb_in(&sdp->sd_sb, sb);
kunmap(page);
__free_page(page);
error = gfs2_check_sb(sdp, &sdp->sd_sb, silent);
if (error)
return error;
sdp->sd_fsb2bb_shift = sdp->sd_sb.sb_bsize_shift -
GFS2_BASIC_BLOCK_SHIFT;
sdp->sd_fsb2bb = 1 << 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);
/* Compute maximum reservation required to add a entry to a directory */
hash_blocks = DIV_ROUND_UP(sizeof(u64) * (1 << 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;
gfs2_assert(sdp, sdp->sd_max_height <= GFS2_MAX_META_HEIGHT);
sdp->sd_jheightsize[0] = sdp->sd_sb.sb_bsize -
sizeof(struct gfs2_dinode);
sdp->sd_jheightsize[1] = sdp->sd_jbsize * sdp->sd_diptrs;
for (x = 2;; x++) {
u64 space, d;
u32 m;
space = sdp->sd_jheightsize[x - 1] * sdp->sd_inptrs;
d = space;
m = do_div(d, sdp->sd_inptrs);
if (d != sdp->sd_jheightsize[x - 1] || m)
break;
sdp->sd_jheightsize[x] = space;
}
sdp->sd_max_jheight = x;
gfs2_assert(sdp, sdp->sd_max_jheight <= GFS2_MAX_META_HEIGHT);
return 0;
}
/**
* gfs2_jindex_hold - Grab a lock on the jindex
* @sdp: The GFS2 superblock
* @ji_gh: the holder for the jindex glock
*
* This is very similar to the gfs2_rindex_hold() function, except that
* in general we hold the jindex lock for longer periods of time and
* we grab it far less frequently (in general) then the rgrp lock.
*
* Returns: errno
*/
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,
GL_LOCAL_EXCL, 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_search(sdp->sd_jindex, &name, NULL, 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;
jd->jd_inode = gfs2_lookupi(sdp->sd_jindex, &name, 1, NULL);
if (!jd->jd_inode || IS_ERR(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;
}
/**
* 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);
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;
}
void gfs2_jdesc_make_dirty(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);
if (jd)
jd->jd_dirty = 1;
spin_unlock(&sdp->sd_jindex_spin);
}
struct gfs2_jdesc *gfs2_jdesc_find_dirty(struct gfs2_sbd *sdp)
{
struct gfs2_jdesc *jd;
int found = 0;
spin_lock(&sdp->sd_jindex_spin);
list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
if (jd->jd_dirty) {
jd->jd_dirty = 0;
found = 1;
break;
}
}
spin_unlock(&sdp->sd_jindex_spin);
if (!found)
jd = NULL;
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);
int ar;
int error;
if (ip->i_di.di_size < (8 << 20) || ip->i_di.di_size > (1 << 30) ||
(ip->i_di.di_size & (sdp->sd_sb.sb_bsize - 1))) {
gfs2_consist_inode(ip);
return -EIO;
}
jd->jd_blocks = ip->i_di.di_size >> sdp->sd_sb.sb_bsize_shift;
error = gfs2_write_alloc_required(ip, 0, ip->i_di.di_size, &ar);
if (!error && ar) {
gfs2_consist_inode(ip);
error = -EIO;
}
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 t_gh;
struct gfs2_log_header_host head;
int error;
error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
GL_LOCAL_EXCL, &t_gh);
if (error)
return error;
gfs2_meta_cache_flush(ip);
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(&t_gh);
return 0;
fail:
t_gh.gh_flags |= GL_NOCACHE;
gfs2_glock_dq_uninit(&t_gh);
return error;
}
/**
* gfs2_make_fs_ro - Turn a Read-Write FS into a Read-Only one
* @sdp: the filesystem
*
* Returns: errno
*/
int gfs2_make_fs_ro(struct gfs2_sbd *sdp)
{
struct gfs2_holder t_gh;
int error;
gfs2_quota_sync(sdp);
gfs2_statfs_sync(sdp);
error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_SHARED,
GL_LOCAL_EXCL | GL_NOCACHE,
&t_gh);
if (error && !test_bit(SDF_SHUTDOWN, &sdp->sd_flags))
return error;
gfs2_meta_syncfs(sdp);
gfs2_log_shutdown(sdp);
clear_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags);
if (t_gh.gh_gl)
gfs2_glock_dq_uninit(&t_gh);
gfs2_quota_cleanup(sdp);
return error;
}
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 buffer_head *l_bh;
int error;
error = gfs2_meta_inode_buffer(l_ip, &l_bh);
if (error)
return;
mutex_lock(&sdp->sd_statfs_mutex);
gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
mutex_unlock(&sdp->sd_statfs_mutex);
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));
spin_unlock(&sdp->sd_statfs_spin);
brelse(l_bh);
}
int gfs2_statfs_sync(struct gfs2_sbd *sdp)
{
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;
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;
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;
mutex_lock(&sdp->sd_statfs_mutex);
gfs2_trans_add_bh(l_ip->i_gl, l_bh, 1);
mutex_unlock(&sdp->sd_statfs_mutex);
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_bh(m_ip->i_gl, m_bh, 1);
gfs2_statfs_change_out(m_sc, m_bh->b_data + sizeof(struct gfs2_dinode));
gfs2_trans_end(sdp);
out_bh2:
brelse(l_bh);
out_bh:
brelse(m_bh);
out:
gfs2_glock_dq_uninit(&gh);
return error;
}
/**
* gfs2_statfs_i - Do a statfs
* @sdp: the filesystem
* @sg: the sg structure
*
* Returns: errno
*/
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;
}
/**
* 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_ri.ri_data;
sc->sc_free += rgd->rd_rg.rg_free;
sc->sc_dinodes += rgd->rd_rg.rg_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
*/
int gfs2_statfs_slow(struct gfs2_sbd *sdp, struct gfs2_statfs_change_host *sc)
{
struct gfs2_holder ri_gh;
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;
error = gfs2_rindex_hold(sdp, &ri_gh);
if (error)
goto out;
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();
}
gfs2_glock_dq_uninit(&ri_gh);
out:
kfree(gha);
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,
struct gfs2_holder *t_gh)
{
struct gfs2_inode *ip;
struct gfs2_holder ji_gh;
struct gfs2_jdesc *jd;
struct lfcc *lfcc;
LIST_HEAD(list);
struct gfs2_log_header_host lh;
int error;
error = gfs2_jindex_hold(sdp, &ji_gh);
if (error)
return 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);
}
error = gfs2_glock_nq_init(sdp->sd_trans_gl, LM_ST_DEFERRED,
LM_FLAG_PRIORITY | GL_NOCACHE,
t_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_glock_dq_uninit(t_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);
}
gfs2_glock_dq_uninit(&ji_gh);
return error;
}
/**
* gfs2_freeze_fs - freezes the file system
* @sdp: the file system
*
* This function flushes data and meta data for all machines by
* aquiring the transaction log exclusively. All journals are
* ensured to be in a clean state as well.
*
* Returns: errno
*/
int gfs2_freeze_fs(struct gfs2_sbd *sdp)
{
int error = 0;
mutex_lock(&sdp->sd_freeze_lock);
if (!sdp->sd_freeze_count++) {
error = gfs2_lock_fs_check_clean(sdp, &sdp->sd_freeze_gh);
if (error)
sdp->sd_freeze_count--;
}
mutex_unlock(&sdp->sd_freeze_lock);
return error;
}
/**
* gfs2_unfreeze_fs - unfreezes the file system
* @sdp: the file system
*
* This function allows the file system to proceed by unlocking
* the exclusively held transaction lock. Other GFS2 nodes are
* now free to acquire the lock shared and go on with their lives.
*
*/
void gfs2_unfreeze_fs(struct gfs2_sbd *sdp)
{
mutex_lock(&sdp->sd_freeze_lock);
if (sdp->sd_freeze_count && !--sdp->sd_freeze_count)
gfs2_glock_dq_uninit(&sdp->sd_freeze_gh);
mutex_unlock(&sdp->sd_freeze_lock);
}