diff options
Diffstat (limited to 'fs/super.c')
-rw-r--r-- | fs/super.c | 78 |
1 files changed, 31 insertions, 47 deletions
diff --git a/fs/super.c b/fs/super.c index 50728d9c1a05..f3a8c008e164 100644 --- a/fs/super.c +++ b/fs/super.c @@ -144,6 +144,9 @@ static unsigned long super_cache_count(struct shrinker *shrink, total_objects += list_lru_shrink_count(&sb->s_dentry_lru, sc); total_objects += list_lru_shrink_count(&sb->s_inode_lru, sc); + if (!total_objects) + return SHRINK_EMPTY; + total_objects = vfs_pressure_ratio(total_objects); return total_objects; } @@ -244,10 +247,6 @@ static struct super_block *alloc_super(struct file_system_type *type, int flags, INIT_LIST_HEAD(&s->s_inodes_wb); spin_lock_init(&s->s_inode_wblist_lock); - if (list_lru_init_memcg(&s->s_dentry_lru)) - goto fail; - if (list_lru_init_memcg(&s->s_inode_lru)) - goto fail; s->s_count = 1; atomic_set(&s->s_active, 1); mutex_init(&s->s_vfs_rename_mutex); @@ -265,6 +264,10 @@ static struct super_block *alloc_super(struct file_system_type *type, int flags, s->s_shrink.flags = SHRINKER_NUMA_AWARE | SHRINKER_MEMCG_AWARE; if (prealloc_shrinker(&s->s_shrink)) goto fail; + if (list_lru_init_memcg(&s->s_dentry_lru, &s->s_shrink)) + goto fail; + if (list_lru_init_memcg(&s->s_inode_lru, &s->s_shrink)) + goto fail; return s; fail: @@ -978,58 +981,42 @@ void emergency_thaw_all(void) } } -/* - * Unnamed block devices are dummy devices used by virtual - * filesystems which don't use real block-devices. -- jrs - */ - static DEFINE_IDA(unnamed_dev_ida); -static DEFINE_SPINLOCK(unnamed_dev_lock);/* protects the above */ -/* Many userspace utilities consider an FSID of 0 invalid. - * Always return at least 1 from get_anon_bdev. - */ -static int unnamed_dev_start = 1; +/** + * get_anon_bdev - Allocate a block device for filesystems which don't have one. + * @p: Pointer to a dev_t. + * + * Filesystems which don't use real block devices can call this function + * to allocate a virtual block device. + * + * Context: Any context. Frequently called while holding sb_lock. + * Return: 0 on success, -EMFILE if there are no anonymous bdevs left + * or -ENOMEM if memory allocation failed. + */ int get_anon_bdev(dev_t *p) { int dev; - int error; - retry: - if (ida_pre_get(&unnamed_dev_ida, GFP_ATOMIC) == 0) - return -ENOMEM; - spin_lock(&unnamed_dev_lock); - error = ida_get_new_above(&unnamed_dev_ida, unnamed_dev_start, &dev); - if (!error) - unnamed_dev_start = dev + 1; - spin_unlock(&unnamed_dev_lock); - if (error == -EAGAIN) - /* We raced and lost with another CPU. */ - goto retry; - else if (error) - return -EAGAIN; - - if (dev >= (1 << MINORBITS)) { - spin_lock(&unnamed_dev_lock); - ida_remove(&unnamed_dev_ida, dev); - if (unnamed_dev_start > dev) - unnamed_dev_start = dev; - spin_unlock(&unnamed_dev_lock); - return -EMFILE; - } - *p = MKDEV(0, dev & MINORMASK); + /* + * Many userspace utilities consider an FSID of 0 invalid. + * Always return at least 1 from get_anon_bdev. + */ + dev = ida_alloc_range(&unnamed_dev_ida, 1, (1 << MINORBITS) - 1, + GFP_ATOMIC); + if (dev == -ENOSPC) + dev = -EMFILE; + if (dev < 0) + return dev; + + *p = MKDEV(0, dev); return 0; } EXPORT_SYMBOL(get_anon_bdev); void free_anon_bdev(dev_t dev) { - int slot = MINOR(dev); - spin_lock(&unnamed_dev_lock); - ida_remove(&unnamed_dev_ida, slot); - if (slot < unnamed_dev_start) - unnamed_dev_start = slot; - spin_unlock(&unnamed_dev_lock); + ida_free(&unnamed_dev_ida, MINOR(dev)); } EXPORT_SYMBOL(free_anon_bdev); @@ -1037,7 +1024,6 @@ int set_anon_super(struct super_block *s, void *data) { return get_anon_bdev(&s->s_dev); } - EXPORT_SYMBOL(set_anon_super); void kill_anon_super(struct super_block *sb) @@ -1046,7 +1032,6 @@ void kill_anon_super(struct super_block *sb) generic_shutdown_super(sb); free_anon_bdev(dev); } - EXPORT_SYMBOL(kill_anon_super); void kill_litter_super(struct super_block *sb) @@ -1055,7 +1040,6 @@ void kill_litter_super(struct super_block *sb) d_genocide(sb->s_root); kill_anon_super(sb); } - EXPORT_SYMBOL(kill_litter_super); static int ns_test_super(struct super_block *sb, void *data) |