diff options
Diffstat (limited to 'fs/gfs2/ops_fstype.c')
-rw-r--r-- | fs/gfs2/ops_fstype.c | 135 |
1 files changed, 118 insertions, 17 deletions
diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c index 52fb6c048981..e5ee06231ae5 100644 --- a/fs/gfs2/ops_fstype.c +++ b/fs/gfs2/ops_fstype.c @@ -1114,7 +1114,7 @@ void gfs2_online_uevent(struct gfs2_sbd *sdp) * Returns: errno */ -static int fill_super(struct super_block *sb, void *data, int silent) +static int fill_super(struct super_block *sb, struct gfs2_args *args, int silent) { struct gfs2_sbd *sdp; struct gfs2_holder mount_gh; @@ -1125,17 +1125,7 @@ static int fill_super(struct super_block *sb, void *data, int silent) printk(KERN_WARNING "GFS2: can't alloc struct gfs2_sbd\n"); return -ENOMEM; } - - sdp->sd_args.ar_quota = GFS2_QUOTA_DEFAULT; - sdp->sd_args.ar_data = GFS2_DATA_DEFAULT; - sdp->sd_args.ar_commit = 60; - sdp->sd_args.ar_errors = GFS2_ERRORS_DEFAULT; - - error = gfs2_mount_args(sdp, &sdp->sd_args, data); - if (error) { - printk(KERN_WARNING "GFS2: can't parse mount arguments\n"); - goto fail; - } + sdp->sd_args = *args; if (sdp->sd_args.ar_spectator) { sb->s_flags |= MS_RDONLY; @@ -1243,18 +1233,125 @@ fail: return error; } -static int gfs2_get_sb(struct file_system_type *fs_type, int flags, - const char *dev_name, void *data, struct vfsmount *mnt) +static int set_gfs2_super(struct super_block *s, void *data) { - return get_sb_bdev(fs_type, flags, dev_name, data, fill_super, mnt); + s->s_bdev = data; + s->s_dev = s->s_bdev->bd_dev; + + /* + * We set the bdi here to the queue backing, file systems can + * overwrite this in ->fill_super() + */ + s->s_bdi = &bdev_get_queue(s->s_bdev)->backing_dev_info; + return 0; } -static int test_meta_super(struct super_block *s, void *ptr) +static int test_gfs2_super(struct super_block *s, void *ptr) { struct block_device *bdev = ptr; return (bdev == s->s_bdev); } +/** + * gfs2_get_sb - Get the GFS2 superblock + * @fs_type: The GFS2 filesystem type + * @flags: Mount flags + * @dev_name: The name of the device + * @data: The mount arguments + * @mnt: The vfsmnt for this mount + * + * Q. Why not use get_sb_bdev() ? + * A. We need to select one of two root directories to mount, independent + * of whether this is the initial, or subsequent, mount of this sb + * + * Returns: 0 or -ve on error + */ + +static int gfs2_get_sb(struct file_system_type *fs_type, int flags, + const char *dev_name, void *data, struct vfsmount *mnt) +{ + struct block_device *bdev; + struct super_block *s; + fmode_t mode = FMODE_READ; + int error; + struct gfs2_args args; + struct gfs2_sbd *sdp; + + if (!(flags & MS_RDONLY)) + mode |= FMODE_WRITE; + + bdev = open_bdev_exclusive(dev_name, mode, fs_type); + if (IS_ERR(bdev)) + return PTR_ERR(bdev); + + /* + * 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(&bdev->bd_fsfreeze_mutex); + if (bdev->bd_fsfreeze_count > 0) { + mutex_unlock(&bdev->bd_fsfreeze_mutex); + error = -EBUSY; + goto error_bdev; + } + s = sget(fs_type, test_gfs2_super, set_gfs2_super, bdev); + mutex_unlock(&bdev->bd_fsfreeze_mutex); + error = PTR_ERR(s); + if (IS_ERR(s)) + goto error_bdev; + + memset(&args, 0, sizeof(args)); + args.ar_quota = GFS2_QUOTA_DEFAULT; + args.ar_data = GFS2_DATA_DEFAULT; + args.ar_commit = 60; + args.ar_errors = GFS2_ERRORS_DEFAULT; + + error = gfs2_mount_args(&args, data); + if (error) { + printk(KERN_WARNING "GFS2: can't parse mount arguments\n"); + if (s->s_root) + goto error_super; + deactivate_locked_super(s); + return error; + } + + if (s->s_root) { + error = -EBUSY; + if ((flags ^ s->s_flags) & MS_RDONLY) + goto error_super; + close_bdev_exclusive(bdev, mode); + } else { + char b[BDEVNAME_SIZE]; + + s->s_flags = flags; + s->s_mode = mode; + strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id)); + sb_set_blocksize(s, block_size(bdev)); + error = fill_super(s, &args, flags & MS_SILENT ? 1 : 0); + if (error) { + deactivate_locked_super(s); + return error; + } + s->s_flags |= MS_ACTIVE; + bdev->bd_super = s; + } + + sdp = s->s_fs_info; + mnt->mnt_sb = s; + if (args.ar_meta) + mnt->mnt_root = dget(sdp->sd_master_dir); + else + mnt->mnt_root = dget(sdp->sd_root_dir); + return 0; + +error_super: + deactivate_locked_super(s); +error_bdev: + close_bdev_exclusive(bdev, mode); + return error; +} + static int set_meta_super(struct super_block *s, void *ptr) { return -EINVAL; @@ -1274,13 +1371,17 @@ static int gfs2_get_sb_meta(struct file_system_type *fs_type, int flags, dev_name, error); return error; } - s = sget(&gfs2_fs_type, test_meta_super, set_meta_super, + s = sget(&gfs2_fs_type, test_gfs2_super, set_meta_super, path.dentry->d_inode->i_sb->s_bdev); path_put(&path); if (IS_ERR(s)) { printk(KERN_WARNING "GFS2: gfs2 mount does not exist\n"); return PTR_ERR(s); } + if ((flags ^ s->s_flags) & MS_RDONLY) { + deactivate_locked_super(s); + return -EBUSY; + } sdp = s->s_fs_info; mnt->mnt_sb = s; mnt->mnt_root = dget(sdp->sd_master_dir); |