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Diffstat (limited to 'fs/super.c')
-rw-r--r--fs/super.c93
1 files changed, 20 insertions, 73 deletions
diff --git a/fs/super.c b/fs/super.c
index 98bb0629ee10..2c6cdea2ab2d 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -307,7 +307,7 @@ static void __put_super(struct super_block *s)
* Drops a temporary reference, frees superblock if there's no
* references left.
*/
-static void put_super(struct super_block *sb)
+void put_super(struct super_block *sb)
{
spin_lock(&sb_lock);
__put_super(sb);
@@ -740,7 +740,14 @@ void iterate_supers_type(struct file_system_type *type,
EXPORT_SYMBOL(iterate_supers_type);
-static struct super_block *__get_super(struct block_device *bdev, bool excl)
+/**
+ * get_super - get the superblock of a device
+ * @bdev: device to get the superblock for
+ *
+ * Scans the superblock list and finds the superblock of the file system
+ * mounted on the device given. %NULL is returned if no match is found.
+ */
+struct super_block *get_super(struct block_device *bdev)
{
struct super_block *sb;
@@ -755,17 +762,11 @@ rescan:
if (sb->s_bdev == bdev) {
sb->s_count++;
spin_unlock(&sb_lock);
- if (!excl)
- down_read(&sb->s_umount);
- else
- down_write(&sb->s_umount);
+ down_read(&sb->s_umount);
/* still alive? */
if (sb->s_root && (sb->s_flags & SB_BORN))
return sb;
- if (!excl)
- up_read(&sb->s_umount);
- else
- up_write(&sb->s_umount);
+ up_read(&sb->s_umount);
/* nope, got unmounted */
spin_lock(&sb_lock);
__put_super(sb);
@@ -777,66 +778,6 @@ rescan:
}
/**
- * get_super - get the superblock of a device
- * @bdev: device to get the superblock for
- *
- * Scans the superblock list and finds the superblock of the file system
- * mounted on the device given. %NULL is returned if no match is found.
- */
-struct super_block *get_super(struct block_device *bdev)
-{
- return __get_super(bdev, false);
-}
-EXPORT_SYMBOL(get_super);
-
-static struct super_block *__get_super_thawed(struct block_device *bdev,
- bool excl)
-{
- while (1) {
- struct super_block *s = __get_super(bdev, excl);
- if (!s || s->s_writers.frozen == SB_UNFROZEN)
- return s;
- if (!excl)
- up_read(&s->s_umount);
- else
- up_write(&s->s_umount);
- wait_event(s->s_writers.wait_unfrozen,
- s->s_writers.frozen == SB_UNFROZEN);
- put_super(s);
- }
-}
-
-/**
- * get_super_thawed - get thawed superblock of a device
- * @bdev: device to get the superblock for
- *
- * Scans the superblock list and finds the superblock of the file system
- * mounted on the device. The superblock is returned once it is thawed
- * (or immediately if it was not frozen). %NULL is returned if no match
- * is found.
- */
-struct super_block *get_super_thawed(struct block_device *bdev)
-{
- return __get_super_thawed(bdev, false);
-}
-EXPORT_SYMBOL(get_super_thawed);
-
-/**
- * get_super_exclusive_thawed - get thawed superblock of a device
- * @bdev: device to get the superblock for
- *
- * Scans the superblock list and finds the superblock of the file system
- * mounted on the device. The superblock is returned once it is thawed
- * (or immediately if it was not frozen) and s_umount semaphore is held
- * in exclusive mode. %NULL is returned if no match is found.
- */
-struct super_block *get_super_exclusive_thawed(struct block_device *bdev)
-{
- return __get_super_thawed(bdev, true);
-}
-EXPORT_SYMBOL(get_super_exclusive_thawed);
-
-/**
* get_active_super - get an active reference to the superblock of a device
* @bdev: device to get the superblock for
*
@@ -867,7 +808,7 @@ restart:
return NULL;
}
-struct super_block *user_get_super(dev_t dev)
+struct super_block *user_get_super(dev_t dev, bool excl)
{
struct super_block *sb;
@@ -879,11 +820,17 @@ rescan:
if (sb->s_dev == dev) {
sb->s_count++;
spin_unlock(&sb_lock);
- down_read(&sb->s_umount);
+ if (excl)
+ down_write(&sb->s_umount);
+ else
+ down_read(&sb->s_umount);
/* still alive? */
if (sb->s_root && (sb->s_flags & SB_BORN))
return sb;
- up_read(&sb->s_umount);
+ if (excl)
+ up_write(&sb->s_umount);
+ else
+ up_read(&sb->s_umount);
/* nope, got unmounted */
spin_lock(&sb_lock);
__put_super(sb);