From aa7dfb8954ccf49e026ba13d12991a4eb7defb96 Mon Sep 17 00:00:00 2001 From: Ryusuke Konishi Date: Mon, 8 Jun 2009 01:39:33 +0900 Subject: [PATCH] nilfs2: get rid of bd_mount_sem use from nilfs This will remove every bd_mount_sem use in nilfs. The intended exclusion control was replaced by the previous patch ("nilfs2: correct exclusion control in nilfs_remount function") for nilfs_remount(), and this patch will replace remains with a new mutex that this inserts in nilfs object. Signed-off-by: Ryusuke Konishi Cc: Christoph Hellwig Signed-off-by: Al Viro --- fs/nilfs2/cpfile.c | 6 +++--- fs/nilfs2/super.c | 12 ++++++------ fs/nilfs2/the_nilfs.c | 1 + fs/nilfs2/the_nilfs.h | 2 ++ 4 files changed, 12 insertions(+), 9 deletions(-) diff --git a/fs/nilfs2/cpfile.c b/fs/nilfs2/cpfile.c index 300f1cdfa86..cadd36b14d0 100644 --- a/fs/nilfs2/cpfile.c +++ b/fs/nilfs2/cpfile.c @@ -864,11 +864,11 @@ int nilfs_cpfile_change_cpmode(struct inode *cpfile, __u64 cno, int mode) case NILFS_CHECKPOINT: /* * Check for protecting existing snapshot mounts: - * bd_mount_sem is used to make this operation atomic and + * ns_mount_mutex is used to make this operation atomic and * exclusive with a new mount job. Though it doesn't cover * umount, it's enough for the purpose. */ - down(&nilfs->ns_bdev->bd_mount_sem); + mutex_lock(&nilfs->ns_mount_mutex); if (nilfs_checkpoint_is_mounted(nilfs, cno, 1)) { /* Current implementation does not have to protect plain read-only mounts since they are exclusive @@ -877,7 +877,7 @@ int nilfs_cpfile_change_cpmode(struct inode *cpfile, __u64 cno, int mode) ret = -EBUSY; } else ret = nilfs_cpfile_clear_snapshot(cpfile, cno); - up(&nilfs->ns_bdev->bd_mount_sem); + mutex_unlock(&nilfs->ns_mount_mutex); return ret; case NILFS_SNAPSHOT: return nilfs_cpfile_set_snapshot(cpfile, cno); diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c index f02762fa8ea..1777a3467bd 100644 --- a/fs/nilfs2/super.c +++ b/fs/nilfs2/super.c @@ -764,7 +764,7 @@ int nilfs_store_magic_and_option(struct super_block *sb, * @silent: silent mode flag * @nilfs: the_nilfs struct * - * This function is called exclusively by bd_mount_mutex. + * This function is called exclusively by nilfs->ns_mount_mutex. * So, the recovery process is protected from other simultaneous mounts. */ static int @@ -1105,7 +1105,7 @@ nilfs_get_sb(struct file_system_type *fs_type, int flags, goto failed; } - down(&sd.bdev->bd_mount_sem); + mutex_lock(&nilfs->ns_mount_mutex); if (!sd.cno) { /* @@ -1164,7 +1164,7 @@ nilfs_get_sb(struct file_system_type *fs_type, int flags, need_to_close = 0; } - up(&sd.bdev->bd_mount_sem); + mutex_unlock(&nilfs->ns_mount_mutex); put_nilfs(nilfs); if (need_to_close) close_bdev_exclusive(sd.bdev, flags); @@ -1172,7 +1172,7 @@ nilfs_get_sb(struct file_system_type *fs_type, int flags, return 0; failed_unlock: - up(&sd.bdev->bd_mount_sem); + mutex_unlock(&nilfs->ns_mount_mutex); put_nilfs(nilfs); failed: close_bdev_exclusive(sd.bdev, flags); @@ -1181,14 +1181,14 @@ nilfs_get_sb(struct file_system_type *fs_type, int flags, cancel_new: /* Abandoning the newly allocated superblock */ - up(&sd.bdev->bd_mount_sem); + mutex_unlock(&nilfs->ns_mount_mutex); put_nilfs(nilfs); up_write(&s->s_umount); deactivate_super(s); /* * deactivate_super() invokes close_bdev_exclusive(). * We must finish all post-cleaning before this call; - * put_nilfs() and unlocking bd_mount_sem need the block device. + * put_nilfs() needs the block device. */ return err; } diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c index 06e8dfd538d..e4e5c78bcc9 100644 --- a/fs/nilfs2/the_nilfs.c +++ b/fs/nilfs2/the_nilfs.c @@ -73,6 +73,7 @@ static struct the_nilfs *alloc_nilfs(struct block_device *bdev) atomic_set(&nilfs->ns_ndirtyblks, 0); init_rwsem(&nilfs->ns_sem); init_rwsem(&nilfs->ns_super_sem); + mutex_init(&nilfs->ns_mount_mutex); mutex_init(&nilfs->ns_writer_mutex); INIT_LIST_HEAD(&nilfs->ns_list); INIT_LIST_HEAD(&nilfs->ns_supers); diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h index d0cf4fb7c9c..e8adbffc626 100644 --- a/fs/nilfs2/the_nilfs.h +++ b/fs/nilfs2/the_nilfs.h @@ -49,6 +49,7 @@ enum { * @ns_writer: back pointer to writable nilfs_sb_info * @ns_sem: semaphore for shared states * @ns_super_sem: semaphore for global operations across super block instances + * @ns_mount_mutex: mutex protecting mount process of nilfs * @ns_writer_mutex: mutex protecting ns_writer attach/detach * @ns_writer_refcount: number of referrers on ns_writer * @ns_current: back pointer to current mount @@ -98,6 +99,7 @@ struct the_nilfs { struct nilfs_sb_info *ns_writer; struct rw_semaphore ns_sem; struct rw_semaphore ns_super_sem; + struct mutex ns_mount_mutex; struct mutex ns_writer_mutex; atomic_t ns_writer_refcount;