diff options
| author | Tejun Heo <tj@kernel.org> | 2013-11-28 14:54:42 -0500 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-11-29 18:10:48 -0800 |
| commit | df394fb56c64244b30b442e9e02de1a2d9c5a98b (patch) | |
| tree | fc6b65c4356680c92df02c12ea0e386eeff9c992 | |
| parent | bc755553df9ab33f389c1a0a8bd0b4f4646e80ef (diff) | |
sysfs, kernfs: make super_blocks bind to different kernfs_roots
kernfs is being updated to allow multiple sysfs_dirent hierarchies so
that it can also be used by other users. Currently, sysfs
super_blocks are always attached to one kernfs_root - sysfs_root - and
distinguished only by their namespace tags.
This patch adds sysfs_super_info->root and update
sysfs_fill/test_super() so that super_blocks are identified by the
combination of both the associated kernfs_root and namespace tag.
This allows mounting different kernfs hierarchies.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/sysfs/mount.c | 10 | ||||
| -rw-r--r-- | fs/sysfs/sysfs.h | 6 |
2 files changed, 12 insertions, 4 deletions
diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c index 0b5661b462f7..f143b203a7e6 100644 --- a/fs/sysfs/mount.c +++ b/fs/sysfs/mount.c @@ -37,6 +37,7 @@ struct sysfs_dirent *sysfs_root_sd; static int sysfs_fill_super(struct super_block *sb) { + struct sysfs_super_info *info = sysfs_info(sb); struct inode *inode; struct dentry *root; @@ -48,7 +49,7 @@ static int sysfs_fill_super(struct super_block *sb) /* get root inode, initialize and unlock it */ mutex_lock(&sysfs_mutex); - inode = sysfs_get_inode(sb, sysfs_root_sd); + inode = sysfs_get_inode(sb, info->root->sd); mutex_unlock(&sysfs_mutex); if (!inode) { pr_debug("sysfs: could not get root inode\n"); @@ -61,8 +62,8 @@ static int sysfs_fill_super(struct super_block *sb) pr_debug("%s: could not get root dentry!\n", __func__); return -ENOMEM; } - kernfs_get(sysfs_root_sd); - root->d_fsdata = sysfs_root_sd; + kernfs_get(info->root->sd); + root->d_fsdata = info->root->sd; sb->s_root = root; sb->s_d_op = &sysfs_dentry_ops; return 0; @@ -73,7 +74,7 @@ static int sysfs_test_super(struct super_block *sb, void *data) struct sysfs_super_info *sb_info = sysfs_info(sb); struct sysfs_super_info *info = data; - return sb_info->ns == info->ns; + return sb_info->root == info->root && sb_info->ns == info->ns; } static int sysfs_set_super(struct super_block *sb, void *data) @@ -110,6 +111,7 @@ static struct dentry *sysfs_mount(struct file_system_type *fs_type, if (!info) return ERR_PTR(-ENOMEM); + info->root = sysfs_root; info->ns = kobj_ns_grab_current(KOBJ_NS_TYPE_NET); sb = sget(fs_type, sysfs_test_super, sysfs_set_super, flags, info); diff --git a/fs/sysfs/sysfs.h b/fs/sysfs/sysfs.h index 2b217cef90be..93b4b68458ad 100644 --- a/fs/sysfs/sysfs.h +++ b/fs/sysfs/sysfs.h @@ -20,6 +20,12 @@ struct sysfs_super_info { /* + * The root associated with this super_block. Each super_block is + * identified by the root and ns it's associated with. + */ + struct kernfs_root *root; + + /* * Each sb is associated with one namespace tag, currently the network * namespace of the task which mounted this sysfs instance. If multiple * tags become necessary, make the following an array and compare |