diff options
Diffstat (limited to 'fs/kernfs/mount.c')
| -rw-r--r-- | fs/kernfs/mount.c | 50 |
1 files changed, 44 insertions, 6 deletions
diff --git a/fs/kernfs/mount.c b/fs/kernfs/mount.c index 0f4152defe7..95dcd1d558b 100644 --- a/fs/kernfs/mount.c +++ b/fs/kernfs/mount.c @@ -19,13 +19,50 @@ struct kmem_cache *kernfs_node_cache; -static const struct super_operations kernfs_sops = { +static int kernfs_sop_remount_fs(struct super_block *sb, int *flags, char *data) +{ + struct kernfs_root *root = kernfs_info(sb)->root; + struct kernfs_syscall_ops *scops = root->syscall_ops; + + if (scops && scops->remount_fs) + return scops->remount_fs(root, flags, data); + return 0; +} + +static int kernfs_sop_show_options(struct seq_file *sf, struct dentry *dentry) +{ + struct kernfs_root *root = kernfs_root(dentry->d_fsdata); + struct kernfs_syscall_ops *scops = root->syscall_ops; + + if (scops && scops->show_options) + return scops->show_options(sf, root); + return 0; +} + +const struct super_operations kernfs_sops = { .statfs = simple_statfs, .drop_inode = generic_delete_inode, .evict_inode = kernfs_evict_inode, + + .remount_fs = kernfs_sop_remount_fs, + .show_options = kernfs_sop_show_options, }; -static int kernfs_fill_super(struct super_block *sb) +/** + * kernfs_root_from_sb - determine kernfs_root associated with a super_block + * @sb: the super_block in question + * + * Return the kernfs_root associated with @sb. If @sb is not a kernfs one, + * %NULL is returned. + */ +struct kernfs_root *kernfs_root_from_sb(struct super_block *sb) +{ + if (sb->s_op == &kernfs_sops) + return kernfs_info(sb)->root; + return NULL; +} + +static int kernfs_fill_super(struct super_block *sb, unsigned long magic) { struct kernfs_super_info *info = kernfs_info(sb); struct inode *inode; @@ -33,7 +70,7 @@ static int kernfs_fill_super(struct super_block *sb) sb->s_blocksize = PAGE_CACHE_SIZE; sb->s_blocksize_bits = PAGE_CACHE_SHIFT; - sb->s_magic = SYSFS_MAGIC; + sb->s_magic = magic; sb->s_op = &kernfs_sops; sb->s_time_gran = 1; @@ -94,6 +131,7 @@ const void *kernfs_super_ns(struct super_block *sb) * @fs_type: file_system_type of the fs being mounted * @flags: mount flags specified for the mount * @root: kernfs_root of the hierarchy being mounted + * @magic: file system specific magic number * @new_sb_created: tell the caller if we allocated a new superblock * @ns: optional namespace tag of the mount * @@ -105,8 +143,8 @@ const void *kernfs_super_ns(struct super_block *sb) * The return value can be passed to the vfs layer verbatim. */ struct dentry *kernfs_mount_ns(struct file_system_type *fs_type, int flags, - struct kernfs_root *root, bool *new_sb_created, - const void *ns) + struct kernfs_root *root, unsigned long magic, + bool *new_sb_created, const void *ns) { struct super_block *sb; struct kernfs_super_info *info; @@ -129,7 +167,7 @@ struct dentry *kernfs_mount_ns(struct file_system_type *fs_type, int flags, *new_sb_created = !sb->s_root; if (!sb->s_root) { - error = kernfs_fill_super(sb); + error = kernfs_fill_super(sb, magic); if (error) { deactivate_locked_super(sb); return ERR_PTR(error); |