Hi, Could anyone help to integrate this patch into kernel-adaptation-mrst? Thanks!
> -----Original Message----- > From: Zhong, Xin > Sent: Monday, April 18, 2011 3:58 PM > To: [email protected] > Cc: Zhong, Xin > Subject: [PATCH] Btrfs: fix subvolume mount by name problem when > default mount subvolume is set > > This patch is already accepted in upstream btrfs-unstable git > tree as commit e15d0542426f063dc53b4c51bdfc11e0bbe4d298. > Below is a backport to mrst 2.6.37 kernel. > > We create two subvolumes (meego_root and meego_home) in > btrfs root directory. And set meego_root as default mount > subvolume. After we remount btrfs, meego_root is mounted > to top directory by default. Then when we try to mount > meego_home (subvol=meego_home) to a subdirectory, it failed. > The problem is when default mount subvolume is set to > meego_root, we search meego_home in meego_root but can not find > it. So the solution is to add a new mount option (subvolrootid) > to specify subvol id of root and search subvol name in it. For > our case, now we can use "-o subvolrootid=0,subvol=meego_home) > to mount meego_home. > > Detail information can be found in meego bugzilla: > https://bugs.meego.com/show_bug.cgi?id=15055 > > Signed-off-by: Zhong, Xin <[email protected]> > --- > fs/btrfs/super.c | 42 +++++++++++++++++++++++++++++++++--------- > 1 files changed, 33 insertions(+), 9 deletions(-) > > diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c > index 883c6fa..738e27a 100644 > --- a/fs/btrfs/super.c > +++ b/fs/btrfs/super.c > @@ -71,7 +71,7 @@ enum { > Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, > Opt_compress, > Opt_compress_force, Opt_notreelog, Opt_ratio, Opt_flushoncommit, > Opt_discard, Opt_space_cache, Opt_clear_cache, Opt_err, > - Opt_user_subvol_rm_allowed, > + Opt_user_subvol_rm_allowed, Opt_subvolrootid > }; > > static match_table_t tokens = { > @@ -98,6 +98,7 @@ static match_table_t tokens = { > {Opt_space_cache, "space_cache"}, > {Opt_clear_cache, "clear_cache"}, > {Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"}, > + {Opt_subvolrootid, "subvolrootid=%d"}, > {Opt_err, NULL}, > }; > > @@ -139,6 +140,7 @@ int btrfs_parse_options(struct btrfs_root *root, > char *options) > break; > case Opt_subvol: > case Opt_subvolid: > + case Opt_subvolrootid: > case Opt_device: > /* > * These are parsed by btrfs_parse_early_options > @@ -274,7 +276,7 @@ out: > */ > static int btrfs_parse_early_options(const char *options, fmode_t > flags, > void *holder, char **subvol_name, u64 *subvol_objectid, > - struct btrfs_fs_devices **fs_devices) > + u64 *subvol_rootid, struct btrfs_fs_devices **fs_devices) > { > substring_t args[MAX_OPT_ARGS]; > char *opts, *p; > @@ -314,6 +316,18 @@ static int btrfs_parse_early_options(const char > *options, fmode_t flags, > *subvol_objectid = intarg; > } > break; > + case Opt_subvolrootid: > + intarg = 0; > + error = match_int(&args[0], &intarg); > + if (!error) { > + /* we want the original fs_tree */ > + if (!intarg) > + *subvol_rootid = > + BTRFS_FS_TREE_OBJECTID; > + else > + *subvol_rootid = intarg; > + } > + break; > case Opt_device: > error = btrfs_scan_one_device(match_strdup(&args[0]), > flags, holder, fs_devices); > @@ -601,6 +615,7 @@ static struct dentry *btrfs_mount(struct > file_system_type *fs_type, int flags, > fmode_t mode = FMODE_READ; > char *subvol_name = NULL; > u64 subvol_objectid = 0; > + u64 subvol_rootid = 0; > int error = 0; > > if (!(flags & MS_RDONLY)) > @@ -608,7 +623,7 @@ static struct dentry *btrfs_mount(struct > file_system_type *fs_type, int flags, > > error = btrfs_parse_early_options(data, mode, fs_type, > &subvol_name, &subvol_objectid, > - &fs_devices); > + &subvol_rootid, &fs_devices); > if (error) > return ERR_PTR(error); > > @@ -670,15 +685,17 @@ static struct dentry *btrfs_mount(struct > file_system_type *fs_type, int flags, > s->s_flags |= MS_ACTIVE; > } > > - root = get_default_root(s, subvol_objectid); > - if (IS_ERR(root)) { > - error = PTR_ERR(root); > - deactivate_locked_super(s); > - goto error_free_subvol_name; > - } > /* if they gave us a subvolume name bind mount into that */ > if (strcmp(subvol_name, ".")) { > struct dentry *new_root; > + > + root = get_default_root(s, subvol_rootid); > + if (IS_ERR(root)) { > + error = PTR_ERR(root); > + deactivate_locked_super(s); > + goto error_free_subvol_name; > + } > + > mutex_lock(&root->d_inode->i_mutex); > new_root = lookup_one_len(subvol_name, root, > strlen(subvol_name)); > @@ -699,6 +716,13 @@ static struct dentry *btrfs_mount(struct > file_system_type *fs_type, int flags, > } > dput(root); > root = new_root; > + } else { > + root = get_default_root(s, subvol_objectid); > + if (IS_ERR(root)) { > + error = PTR_ERR(root); > + deactivate_locked_super(s); > + goto error_free_subvol_name; > + } > } > > kfree(subvol_name); > -- > 1.7.0.4 _______________________________________________ MeeGo-kernel mailing list [email protected] http://lists.meego.com/listinfo/meego-kernel
