diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c index 0ef8c71bde8e..a5d1fa4e7552 100644 --- a/fs/nilfs2/super.c +++ b/fs/nilfs2/super.c @@ -35,6 +35,7 @@ #include #include #include +#include #include "nilfs.h" #include "export.h" #include "mdt.h" @@ -1216,7 +1217,6 @@ static int nilfs_remount(struct super_block *sb, int *flags, char *data) } struct nilfs_super_data { - struct block_device *bdev; __u64 cno; int flags; }; @@ -1283,64 +1283,49 @@ static int nilfs_identify(char *data, struct nilfs_super_data *sd) static int nilfs_set_bdev_super(struct super_block *s, void *data) { - s->s_bdev = data; - s->s_dev = s->s_bdev->bd_dev; + s->s_dev = *(dev_t *)data; return 0; } static int nilfs_test_bdev_super(struct super_block *s, void *data) { - return (void *)s->s_bdev == data; + return !(s->s_iflags & SB_I_RETIRED) && s->s_dev == *(dev_t *)data; } static struct dentry * nilfs_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *data) { - struct nilfs_super_data sd; + struct nilfs_super_data sd = { .flags = flags }; struct super_block *s; - struct dentry *root_dentry; - int err, s_new = false; + dev_t dev; + int err; - sd.bdev = blkdev_get_by_path(dev_name, sb_open_mode(flags), fs_type, - NULL); - if (IS_ERR(sd.bdev)) - return ERR_CAST(sd.bdev); + if (nilfs_identify(data, &sd)) + return ERR_PTR(-EINVAL); - sd.cno = 0; - sd.flags = flags; - if (nilfs_identify((char *)data, &sd)) { - err = -EINVAL; - goto failed; - } + err = lookup_bdev(dev_name, &dev); + if (err) + return ERR_PTR(err); - /* - * once the super is inserted into the list by sget, s_umount - * will protect the lockfs code from trying to start a snapshot - * while we are mounting - */ - mutex_lock(&sd.bdev->bd_fsfreeze_mutex); - if (sd.bdev->bd_fsfreeze_count > 0) { - mutex_unlock(&sd.bdev->bd_fsfreeze_mutex); - err = -EBUSY; - goto failed; - } s = sget(fs_type, nilfs_test_bdev_super, nilfs_set_bdev_super, flags, - sd.bdev); - mutex_unlock(&sd.bdev->bd_fsfreeze_mutex); - if (IS_ERR(s)) { - err = PTR_ERR(s); - goto failed; - } + &dev); + if (IS_ERR(s)) + return ERR_CAST(s); if (!s->s_root) { - s_new = true; - - /* New superblock instance created */ - snprintf(s->s_id, sizeof(s->s_id), "%pg", sd.bdev); - sb_set_blocksize(s, block_size(sd.bdev)); - - err = nilfs_fill_super(s, data, flags & SB_SILENT ? 1 : 0); + /* + * We drop s_umount here because we need to open the bdev and + * bdev->open_mutex ranks above s_umount (blkdev_put() -> + * __invalidate_device()). It is safe because we have active sb + * reference and SB_BORN is not set yet. + */ + up_write(&s->s_umount); + err = setup_bdev_super(s, flags, NULL); + down_write(&s->s_umount); + if (!err) + err = nilfs_fill_super(s, data, + flags & SB_SILENT ? 1 : 0); if (err) goto failed_super; @@ -1366,24 +1351,18 @@ nilfs_mount(struct file_system_type *fs_type, int flags, } if (sd.cno) { + struct dentry *root_dentry; + err = nilfs_attach_snapshot(s, sd.cno, &root_dentry); if (err) goto failed_super; - } else { - root_dentry = dget(s->s_root); + return root_dentry; } - if (!s_new) - blkdev_put(sd.bdev, fs_type); - - return root_dentry; + return dget(s->s_root); failed_super: deactivate_locked_super(s); - - failed: - if (!s_new) - blkdev_put(sd.bdev, fs_type); return ERR_PTR(err); }