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-rw-r--r--fs/ext4/extents_status.c33
-rw-r--r--fs/gfs2/glock.c28
-rw-r--r--fs/gfs2/main.c3
-rw-r--r--fs/gfs2/quota.c16
-rw-r--r--fs/gfs2/quota.h6
-rw-r--r--fs/mbcache.c47
-rw-r--r--fs/nfs/dir.c14
-rw-r--r--fs/nfs/internal.h6
-rw-r--r--fs/nfs/super.c3
-rw-r--r--fs/nfsd/nfscache.c32
-rw-r--r--fs/quota/dquot.c29
-rw-r--r--fs/ubifs/shrinker.c29
-rw-r--r--fs/ubifs/super.c3
-rw-r--r--fs/ubifs/ubifs.h5
14 files changed, 158 insertions, 96 deletions
diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
index 2d1bdbe78c0..3981ff78395 100644
--- a/fs/ext4/extents_status.c
+++ b/fs/ext4/extents_status.c
@@ -931,13 +931,15 @@ static int __ext4_es_shrink(struct ext4_sb_info *sbi, int nr_to_scan,
struct ext4_inode_info *ei;
struct list_head *cur, *tmp;
LIST_HEAD(skipped);
- int ret, nr_shrunk = 0;
+ int nr_shrunk = 0;
int retried = 0, skip_precached = 1, nr_skipped = 0;
spin_lock(&sbi->s_es_lru_lock);
retry:
list_for_each_safe(cur, tmp, &sbi->s_es_lru) {
+ int shrunk;
+
/*
* If we have already reclaimed all extents from extent
* status tree, just stop the loop immediately.
@@ -964,13 +966,13 @@ retry:
continue;
write_lock(&ei->i_es_lock);
- ret = __es_try_to_reclaim_extents(ei, nr_to_scan);
+ shrunk = __es_try_to_reclaim_extents(ei, nr_to_scan);
if (ei->i_es_lru_nr == 0)
list_del_init(&ei->i_es_lru);
write_unlock(&ei->i_es_lock);
- nr_shrunk += ret;
- nr_to_scan -= ret;
+ nr_shrunk += shrunk;
+ nr_to_scan -= shrunk;
if (nr_to_scan == 0)
break;
}
@@ -1007,7 +1009,20 @@ retry:
return nr_shrunk;
}
-static int ext4_es_shrink(struct shrinker *shrink, struct shrink_control *sc)
+static unsigned long ext4_es_count(struct shrinker *shrink,
+ struct shrink_control *sc)
+{
+ unsigned long nr;
+ struct ext4_sb_info *sbi;
+
+ sbi = container_of(shrink, struct ext4_sb_info, s_es_shrinker);
+ nr = percpu_counter_read_positive(&sbi->s_extent_cache_cnt);
+ trace_ext4_es_shrink_enter(sbi->s_sb, sc->nr_to_scan, nr);
+ return nr;
+}
+
+static unsigned long ext4_es_scan(struct shrinker *shrink,
+ struct shrink_control *sc)
{
struct ext4_sb_info *sbi = container_of(shrink,
struct ext4_sb_info, s_es_shrinker);
@@ -1022,9 +1037,8 @@ static int ext4_es_shrink(struct shrinker *shrink, struct shrink_control *sc)
nr_shrunk = __ext4_es_shrink(sbi, nr_to_scan, NULL);
- ret = percpu_counter_read_positive(&sbi->s_extent_cache_cnt);
trace_ext4_es_shrink_exit(sbi->s_sb, nr_shrunk, ret);
- return ret;
+ return nr_shrunk;
}
void ext4_es_register_shrinker(struct ext4_sb_info *sbi)
@@ -1032,7 +1046,8 @@ void ext4_es_register_shrinker(struct ext4_sb_info *sbi)
INIT_LIST_HEAD(&sbi->s_es_lru);
spin_lock_init(&sbi->s_es_lru_lock);
sbi->s_es_last_sorted = 0;
- sbi->s_es_shrinker.shrink = ext4_es_shrink;
+ sbi->s_es_shrinker.scan_objects = ext4_es_scan;
+ sbi->s_es_shrinker.count_objects = ext4_es_count;
sbi->s_es_shrinker.seeks = DEFAULT_SEEKS;
register_shrinker(&sbi->s_es_shrinker);
}
@@ -1076,7 +1091,7 @@ static int __es_try_to_reclaim_extents(struct ext4_inode_info *ei,
struct ext4_es_tree *tree = &ei->i_es_tree;
struct rb_node *node;
struct extent_status *es;
- int nr_shrunk = 0;
+ unsigned long nr_shrunk = 0;
static DEFINE_RATELIMIT_STATE(_rs, DEFAULT_RATELIMIT_INTERVAL,
DEFAULT_RATELIMIT_BURST);
diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c
index b782bb56085..c2f41b4d00b 100644
--- a/fs/gfs2/glock.c
+++ b/fs/gfs2/glock.c
@@ -1427,21 +1427,22 @@ __acquires(&lru_lock)
* gfs2_dispose_glock_lru() above.
*/
-static void gfs2_scan_glock_lru(int nr)
+static long gfs2_scan_glock_lru(int nr)
{
struct gfs2_glock *gl;
LIST_HEAD(skipped);
LIST_HEAD(dispose);
+ long freed = 0;
spin_lock(&lru_lock);
- while(nr && !list_empty(&lru_list)) {
+ while ((nr-- >= 0) && !list_empty(&lru_list)) {
gl = list_entry(lru_list.next, struct gfs2_glock, gl_lru);
/* Test for being demotable */
if (!test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
list_move(&gl->gl_lru, &dispose);
atomic_dec(&lru_count);
- nr--;
+ freed++;
continue;
}
@@ -1451,23 +1452,28 @@ static void gfs2_scan_glock_lru(int nr)
if (!list_empty(&dispose))
gfs2_dispose_glock_lru(&dispose);
spin_unlock(&lru_lock);
+
+ return freed;
}
-static int gfs2_shrink_glock_memory(struct shrinker *shrink,
- struct shrink_control *sc)
+static unsigned long gfs2_glock_shrink_scan(struct shrinker *shrink,
+ struct shrink_control *sc)
{
- if (sc->nr_to_scan) {
- if (!(sc->gfp_mask & __GFP_FS))
- return -1;
- gfs2_scan_glock_lru(sc->nr_to_scan);
- }
+ if (!(sc->gfp_mask & __GFP_FS))
+ return SHRINK_STOP;
+ return gfs2_scan_glock_lru(sc->nr_to_scan);
+}
+static unsigned long gfs2_glock_shrink_count(struct shrinker *shrink,
+ struct shrink_control *sc)
+{
return vfs_pressure_ratio(atomic_read(&lru_count));
}
static struct shrinker glock_shrinker = {
- .shrink = gfs2_shrink_glock_memory,
.seeks = DEFAULT_SEEKS,
+ .count_objects = gfs2_glock_shrink_count,
+ .scan_objects = gfs2_glock_shrink_scan,
};
/**
diff --git a/fs/gfs2/main.c b/fs/gfs2/main.c
index 7b0f5043cf2..351586e24e3 100644
--- a/fs/gfs2/main.c
+++ b/fs/gfs2/main.c
@@ -32,7 +32,8 @@
struct workqueue_struct *gfs2_control_wq;
static struct shrinker qd_shrinker = {
- .shrink = gfs2_shrink_qd_memory,
+ .count_objects = gfs2_qd_shrink_count,
+ .scan_objects = gfs2_qd_shrink_scan,
.seeks = DEFAULT_SEEKS,
};
diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c
index d550a5d6a05..db441359ee8 100644
--- a/fs/gfs2/quota.c
+++ b/fs/gfs2/quota.c
@@ -75,17 +75,16 @@ static LIST_HEAD(qd_lru_list);
static atomic_t qd_lru_count = ATOMIC_INIT(0);
static DEFINE_SPINLOCK(qd_lru_lock);
-int gfs2_shrink_qd_memory(struct shrinker *shrink, struct shrink_control *sc)
+unsigned long gfs2_qd_shrink_scan(struct shrinker *shrink,
+ struct shrink_control *sc)
{
struct gfs2_quota_data *qd;
struct gfs2_sbd *sdp;
int nr_to_scan = sc->nr_to_scan;
-
- if (nr_to_scan == 0)
- goto out;
+ long freed = 0;
if (!(sc->gfp_mask & __GFP_FS))
- return -1;
+ return SHRINK_STOP;
spin_lock(&qd_lru_lock);
while (nr_to_scan && !list_empty(&qd_lru_list)) {
@@ -110,10 +109,15 @@ int gfs2_shrink_qd_memory(struct shrinker *shrink, struct shrink_control *sc)
kmem_cache_free(gfs2_quotad_cachep, qd);
spin_lock(&qd_lru_lock);
nr_to_scan--;
+ freed++;
}
spin_unlock(&qd_lru_lock);
+ return freed;
+}
-out:
+unsigned long gfs2_qd_shrink_count(struct shrinker *shrink,
+ struct shrink_control *sc)
+{
return vfs_pressure_ratio(atomic_read(&qd_lru_count));
}
diff --git a/fs/gfs2/quota.h b/fs/gfs2/quota.h
index 4f5e6e44ed8..0f64d9deb1b 100644
--- a/fs/gfs2/quota.h
+++ b/fs/gfs2/quota.h
@@ -53,8 +53,10 @@ static inline int gfs2_quota_lock_check(struct gfs2_inode *ip)
return ret;
}
-extern int gfs2_shrink_qd_memory(struct shrinker *shrink,
- struct shrink_control *sc);
+extern unsigned long gfs2_qd_shrink_count(struct shrinker *shrink,
+ struct shrink_control *sc);
+extern unsigned long gfs2_qd_shrink_scan(struct shrinker *shrink,
+ struct shrink_control *sc);
extern const struct quotactl_ops gfs2_quotactl_ops;
#endif /* __QUOTA_DOT_H__ */
diff --git a/fs/mbcache.c b/fs/mbcache.c
index 5eb04767cb2..e519e45bf67 100644
--- a/fs/mbcache.c
+++ b/fs/mbcache.c
@@ -86,18 +86,6 @@ static LIST_HEAD(mb_cache_list);
static LIST_HEAD(mb_cache_lru_list);
static DEFINE_SPINLOCK(mb_cache_spinlock);
-/*
- * What the mbcache registers as to get shrunk dynamically.
- */
-
-static int mb_cache_shrink_fn(struct shrinker *shrink,
- struct shrink_control *sc);
-
-static struct shrinker mb_cache_shrinker = {
- .shrink = mb_cache_shrink_fn,
- .seeks = DEFAULT_SEEKS,
-};
-
static inline int
__mb_cache_entry_is_hashed(struct mb_cache_entry *ce)
{
@@ -151,7 +139,7 @@ forget:
/*
- * mb_cache_shrink_fn() memory pressure callback
+ * mb_cache_shrink_scan() memory pressure callback
*
* This function is called by the kernel memory management when memory
* gets low.
@@ -159,17 +147,16 @@ forget:
* @shrink: (ignored)
* @sc: shrink_control passed from reclaim
*
- * Returns the number of objects which are present in the cache.
+ * Returns the number of objects freed.
*/
-static int
-mb_cache_shrink_fn(struct shrinker *shrink, struct shrink_control *sc)
+static unsigned long
+mb_cache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
{
LIST_HEAD(free_list);
- struct mb_cache *cache;
struct mb_cache_entry *entry, *tmp;
- int count = 0;
int nr_to_scan = sc->nr_to_scan;
gfp_t gfp_mask = sc->gfp_mask;
+ unsigned long freed = 0;
mb_debug("trying to free %d entries", nr_to_scan);
spin_lock(&mb_cache_spinlock);
@@ -179,19 +166,37 @@ mb_cache_shrink_fn(struct shrinker *shrink, struct shrink_control *sc)
struct mb_cache_entry, e_lru_list);
list_move_tail(&ce->e_lru_list, &free_list);
__mb_cache_entry_unhash(ce);
+ freed++;
+ }
+ spin_unlock(&mb_cache_spinlock);
+ list_for_each_entry_safe(entry, tmp, &free_list, e_lru_list) {
+ __mb_cache_entry_forget(entry, gfp_mask);
}
+ return freed;
+}
+
+static unsigned long
+mb_cache_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
+{
+ struct mb_cache *cache;
+ unsigned long count = 0;
+
+ spin_lock(&mb_cache_spinlock);
list_for_each_entry(cache, &mb_cache_list, c_cache_list) {
mb_debug("cache %s (%d)", cache->c_name,
atomic_read(&cache->c_entry_count));
count += atomic_read(&cache->c_entry_count);
}
spin_unlock(&mb_cache_spinlock);
- list_for_each_entry_safe(entry, tmp, &free_list, e_lru_list) {
- __mb_cache_entry_forget(entry, gfp_mask);
- }
+
return vfs_pressure_ratio(count);
}
+static struct shrinker mb_cache_shrinker = {
+ .count_objects = mb_cache_shrink_count,
+ .scan_objects = mb_cache_shrink_scan,
+ .seeks = DEFAULT_SEEKS,
+};
/*
* mb_cache_create() create a new cache
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 813ef257154..de434f309af 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -2006,17 +2006,18 @@ static void nfs_access_free_list(struct list_head *head)
}
}
-int nfs_access_cache_shrinker(struct shrinker *shrink,
- struct shrink_control *sc)
+unsigned long
+nfs_access_cache_scan(struct shrinker *shrink, struct shrink_control *sc)
{
LIST_HEAD(head);
struct nfs_inode *nfsi, *next;
struct nfs_access_entry *cache;
int nr_to_scan = sc->nr_to_scan;
gfp_t gfp_mask = sc->gfp_mask;
+ long freed = 0;
if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
- return (nr_to_scan == 0) ? 0 : -1;
+ return SHRINK_STOP;
spin_lock(&nfs_access_lru_lock);
list_for_each_entry_safe(nfsi, next, &nfs_access_lru_list, access_cache_inode_lru) {
@@ -2032,6 +2033,7 @@ int nfs_access_cache_shrinker(struct shrinker *shrink,
struct nfs_access_entry, lru);
list_move(&cache->lru, &head);
rb_erase(&cache->rb_node, &nfsi->access_cache);
+ freed++;
if (!list_empty(&nfsi->access_cache_entry_lru))
list_move_tail(&nfsi->access_cache_inode_lru,
&nfs_access_lru_list);
@@ -2046,6 +2048,12 @@ remove_lru_entry:
}
spin_unlock(&nfs_access_lru_lock);
nfs_access_free_list(&head);
+ return freed;
+}
+
+unsigned long
+nfs_access_cache_count(struct shrinker *shrink, struct shrink_control *sc)
+{
return vfs_pressure_ratio(atomic_long_read(&nfs_access_nr_entries));
}
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index d388302c005..38da8c2b81a 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -273,8 +273,10 @@ extern struct nfs_client *nfs_init_client(struct nfs_client *clp,
const char *ip_addr);
/* dir.c */
-extern int nfs_access_cache_shrinker(struct shrinker *shrink,
- struct shrink_control *sc);
+extern unsigned long nfs_access_cache_count(struct shrinker *shrink,
+ struct shrink_control *sc);
+extern unsigned long nfs_access_cache_scan(struct shrinker *shrink,
+ struct shrink_control *sc);
struct dentry *nfs_lookup(struct inode *, struct dentry *, unsigned int);
int nfs_create(struct inode *, struct dentry *, umode_t, bool);
int nfs_mkdir(struct inode *, struct dentry *, umode_t);
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 5793f24613c..a03b9c6f948 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -360,7 +360,8 @@ static void unregister_nfs4_fs(void)
#endif
static struct shrinker acl_shrinker = {
- .shrink = nfs_access_cache_shrinker,
+ .count_objects = nfs_access_cache_count,
+ .scan_objects = nfs_access_cache_scan,
.seeks = DEFAULT_SEEKS,
};
diff --git a/fs/nfsd/nfscache.c b/fs/nfsd/nfscache.c
index e76244edd74..9186c7ce0b1 100644
--- a/fs/nfsd/nfscache.c
+++ b/fs/nfsd/nfscache.c
@@ -59,11 +59,14 @@ static unsigned int longest_chain_cachesize;
static int nfsd_cache_append(struct svc_rqst *rqstp, struct kvec *vec);
static void cache_cleaner_func(struct work_struct *unused);
-static int nfsd_reply_cache_shrink(struct shrinker *shrink,
- struct shrink_control *sc);
+static unsigned long nfsd_reply_cache_count(struct shrinker *shrink,
+ struct shrink_control *sc);
+static unsigned long nfsd_reply_cache_scan(struct shrinker *shrink,
+ struct shrink_control *sc);
static struct shrinker nfsd_reply_cache_shrinker = {
- .shrink = nfsd_reply_cache_shrink,
+ .scan_objects = nfsd_reply_cache_scan,
+ .count_objects = nfsd_reply_cache_count,
.seeks = 1,
};
@@ -232,16 +235,18 @@ nfsd_cache_entry_expired(struct svc_cacherep *rp)
* Walk the LRU list and prune off entries that are older than RC_EXPIRE.
* Also prune the oldest ones when the total exceeds the max number of entries.
*/
-static void
+static long
prune_cache_entries(void)
{
struct svc_cacherep *rp, *tmp;
+ long freed = 0;
list_for_each_entry_safe(rp, tmp, &lru_head, c_lru) {
if (!nfsd_cache_entry_expired(rp) &&
num_drc_entries <= max_drc_entries)
break;
nfsd_reply_cache_free_locked(rp);
+ freed++;
}
/*
@@ -254,6 +259,7 @@ prune_cache_entries(void)
cancel_delayed_work(&cache_cleaner);
else
mod_delayed_work(system_wq, &cache_cleaner, RC_EXPIRE);
+ return freed;
}
static void
@@ -264,20 +270,28 @@ cache_cleaner_func(struct work_struct *unused)
spin_unlock(&cache_lock);
}
-static int
-nfsd_reply_cache_shrink(struct shrinker *shrink, struct shrink_control *sc)
+static unsigned long
+nfsd_reply_cache_count(struct shrinker *shrink, struct shrink_control *sc)
{
- unsigned int num;
+ unsigned long num;
spin_lock(&cache_lock);
- if (sc->nr_to_scan)
- prune_cache_entries();
num = num_drc_entries;
spin_unlock(&cache_lock);
return num;
}
+static unsigned long
+nfsd_reply_cache_scan(struct shrinker *shrink, struct shrink_control *sc)
+{
+ unsigned long freed;
+
+ spin_lock(&cache_lock);
+ freed = prune_cache_entries();
+ spin_unlock(&cache_lock);
+ return freed;
+}
/*
* Walk an xdr_buf and get a CRC for at most the first RC_CSUMLEN bytes
*/
diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index 13eee847605..831d49a4111 100644
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -687,44 +687,37 @@ int dquot_quota_sync(struct super_block *sb, int type)
}
EXPORT_SYMBOL(dquot_quota_sync);
-/* Free unused dquots from cache */
-static void prune_dqcache(int count)
+static unsigned long
+dqcache_shrink_scan(struct shrinker *shrink, struct shrink_control *sc)
{
struct list_head *head;
struct dquot *dquot;
+ unsigned long freed = 0;
head = free_dquots.prev;
- while (head != &free_dquots && count) {
+ while (head != &free_dquots && sc->nr_to_scan) {
dquot = list_entry(head, struct dquot, dq_free);
remove_dquot_hash(dquot);
remove_free_dquot(dquot);
remove_inuse(dquot);
do_destroy_dquot(dquot);
- count--;
+ sc->nr_to_scan--;
+ freed++;
head = free_dquots.prev;
}
+ return freed;
}
-/*
- * This is called from kswapd when we think we need some
- * more memory
- */
-static int shrink_dqcache_memory(struct shrinker *shrink,
- struct shrink_control *sc)
+static unsigned long
+dqcache_shrink_count(struct shrinker *shrink, struct shrink_control *sc)
{
- int nr = sc->nr_to_scan;
-
- if (nr) {
- spin_lock(&dq_list_lock);
- prune_dqcache(nr);
- spin_unlock(&dq_list_lock);
- }
return vfs_pressure_ratio(
percpu_counter_read_positive(&dqstats.counter[DQST_FREE_DQUOTS]));
}
static struct shrinker dqcache_shrinker = {
- .shrink = shrink_dqcache_memory,
+ .count_objects = dqcache_shrink_count,
+ .scan_objects = dqcache_shrink_scan,
.seeks = DEFAULT_SEEKS,
};
diff --git a/fs/ubifs/shrinker.c b/fs/ubifs/shrinker.c
index 9e1d05666fe..f35135e28e9 100644
--- a/fs/ubifs/shrinker.c
+++ b/fs/ubifs/shrinker.c
@@ -277,18 +277,25 @@ static int kick_a_thread(void)
return 0;
}
-int ubifs_shrinker(struct shrinker *shrink, struct shrink_control *sc)
+unsigned long ubifs_shrink_count(struct shrinker *shrink,
+ struct shrink_control *sc)
{
- int nr = sc->nr_to_scan;
- int freed, contention = 0;
long clean_zn_cnt = atomic_long_read(&ubifs_clean_zn_cnt);
- if (nr == 0)
- /*
- * Due to the way UBIFS updates the clean znode counter it may
- * temporarily be negative.
- */
- return clean_zn_cnt >= 0 ? clean_zn_cnt : 1;
+ /*
+ * Due to the way UBIFS updates the clean znode counter it may
+ * temporarily be negative.
+ */
+ return clean_zn_cnt >= 0 ? clean_zn_cnt : 1;
+}
+
+unsigned long ubifs_shrink_scan(struct shrinker *shrink,
+ struct shrink_control *sc)
+{
+ unsigned long nr = sc->nr_to_scan;
+ int contention = 0;
+ unsigned long freed;
+ long clean_zn_cnt = atomic_long_read(&ubifs_clean_zn_cnt);
if (!clean_zn_cnt) {
/*
@@ -316,10 +323,10 @@ int ubifs_shrinker(struct shrinker *shrink, struct shrink_control *sc)
if (!freed && contention) {
dbg_tnc("freed nothing, but contention");
- return -1;
+ return SHRINK_STOP;
}
out:
- dbg_tnc("%d znodes were freed, requested %d", freed, nr);
+ dbg_tnc("%lu znodes were freed, requested %lu", freed, nr);
return freed;
}
diff --git a/fs/ubifs/super.c b/fs/ubifs/super.c
index 879b9976c12..3e4aa7281e0 100644
--- a/fs/ubifs/super.c
+++ b/fs/ubifs/super.c
@@ -49,7 +49,8 @@ struct kmem_cache *ubifs_inode_slab;
/* UBIFS TNC shrinker description */
static struct shrinker ubifs_shrinker_info = {
- .shrink = ubifs_shrinker,
+ .scan_objects = ubifs_shrink_scan,
+ .count_objects = ubifs_shrink_count,
.seeks = DEFAULT_SEEKS,
};
diff --git a/fs/ubifs/ubifs.h b/fs/ubifs/ubifs.h
index b2babce4d70..e8c8cfe1435 100644
--- a/fs/ubifs/ubifs.h
+++ b/fs/ubifs/ubifs.h
@@ -1624,7 +1624,10 @@ int ubifs_tnc_start_commit(struct ubifs_info *c, struct ubifs_zbranch *zroot);
int ubifs_tnc_end_commit(struct ubifs_info *c);
/* shrinker.c */
-int ubifs_shrinker(struct shrinker *shrink, struct shrink_control *sc);
+unsigned long ubifs_shrink_scan(struct shrinker *shrink,
+ struct shrink_control *sc);
+unsigned long ubifs_shrink_count(struct shrinker *shrink,
+ struct shrink_control *sc);
/* commit.c */
int ubifs_bg_thread(void *info);