diff options
| -rw-r--r-- | fs/super.c | 54 |
1 files changed, 14 insertions, 40 deletions
diff --git a/fs/super.c b/fs/super.c index b49a49d70450..78bbbb9b3ee9 100644 --- a/fs/super.c +++ b/fs/super.c @@ -523,37 +523,6 @@ void deactivate_super(struct super_block *s) EXPORT_SYMBOL(deactivate_super); -/** - * grab_super - acquire an active reference - * @s: reference we are trying to make active - * - * Tries to acquire an active reference. grab_super() is used when we - * had just found a superblock in super_blocks or fs_type->fs_supers - * and want to turn it into a full-blown active reference. grab_super() - * is called with sb_lock held and drops it. Returns 1 in case of - * success, 0 if we had failed (superblock contents was already dead or - * dying when grab_super() had been called). Note that this is only - * called for superblocks not in rundown mode (== ones still on ->fs_supers - * of their type), so increment of ->s_count is OK here. - */ -static int grab_super(struct super_block *s) __releases(sb_lock) -{ - bool locked; - - s->s_count++; - spin_unlock(&sb_lock); - locked = super_lock_excl(s); - if (locked) { - if (atomic_inc_not_zero(&s->s_active)) { - put_super(s); - return 1; - } - super_unlock_excl(s); - } - put_super(s); - return 0; -} - static inline bool wait_dead(struct super_block *sb) { unsigned int flags; @@ -567,7 +536,7 @@ static inline bool wait_dead(struct super_block *sb) } /** - * grab_super_dead - acquire an active reference to a superblock + * grab_super - acquire an active reference to a superblock * @sb: superblock to acquire * * Acquire a temporary reference on a superblock and try to trade it for @@ -578,16 +547,21 @@ static inline bool wait_dead(struct super_block *sb) * Return: This returns true if an active reference could be acquired, * false if not. */ -static bool grab_super_dead(struct super_block *sb) +static bool grab_super(struct super_block *sb) { + bool locked; + sb->s_count++; - if (grab_super(sb)) { - put_super(sb); - lockdep_assert_held(&sb->s_umount); - return true; + spin_unlock(&sb_lock); + locked = super_lock_excl(sb); + if (locked) { + if (atomic_inc_not_zero(&sb->s_active)) { + put_super(sb); + return true; + } + super_unlock_excl(sb); } wait_var_event(&sb->s_flags, wait_dead(sb)); - lockdep_assert_not_held(&sb->s_umount); put_super(sb); return false; } @@ -838,7 +812,7 @@ share_extant_sb: warnfc(fc, "reusing existing filesystem in another namespace not allowed"); return ERR_PTR(-EBUSY); } - if (!grab_super_dead(old)) + if (!grab_super(old)) goto retry; destroy_unused_super(s); return old; @@ -882,7 +856,7 @@ retry: destroy_unused_super(s); return ERR_PTR(-EBUSY); } - if (!grab_super_dead(old)) + if (!grab_super(old)) goto retry; destroy_unused_super(s); return old; |