Unverified Commit b74d24f7 authored by Christian Brauner's avatar Christian Brauner Committed by Christian Brauner (Microsoft)
Browse files

fs: port ->getattr() to pass mnt_idmap 



Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: default avatarDave Chinner <dchinner@redhat.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarChristian Brauner (Microsoft) <brauner@kernel.org>
parent c1632a0f

Documentation/filesystems/locking.rst

+1 −1
Original line number Diff line number Diff line
@@ -72,7 +72,7 @@ prototypes:: 
	int (*permission) (struct inode *, int, unsigned int);

	struct posix_acl * (*get_inode_acl)(struct inode *, int, bool);

	int (*setattr) (struct mnt_idmap *, struct dentry *, struct iattr *);

	int (*getattr) (const struct path *, struct kstat *, u32, unsigned int);

	int (*getattr) (struct mnt_idmap *, const struct path *, struct kstat *, u32, unsigned int);

	ssize_t (*listxattr) (struct dentry *, char *, size_t);

	int (*fiemap)(struct inode *, struct fiemap_extent_info *, u64 start, u64 len);

	void (*update_time)(struct inode *, struct timespec *, int);

Documentation/filesystems/vfs.rst

+1 −1
Original line number Diff line number Diff line
@@ -437,7 +437,7 @@ As of kernel 2.6.22, the following members are defined: 
		int (*permission) (struct user_namespace *, struct inode *, int);

		struct posix_acl * (*get_inode_acl)(struct inode *, int, bool);

		int (*setattr) (struct mnt_idmap *, struct dentry *, struct iattr *);

		int (*getattr) (struct user_namespace *, const struct path *, struct kstat *, u32, unsigned int);

		int (*getattr) (struct mnt_idmap *, const struct path *, struct kstat *, u32, unsigned int);

		ssize_t (*listxattr) (struct dentry *, char *, size_t);

		void (*update_time)(struct inode *, struct timespec *, int);

		int (*atomic_open)(struct inode *, struct dentry *, struct file *,

fs/9p/vfs_inode.c

+4 −4
Original line number Diff line number Diff line
@@ -1018,7 +1018,7 @@ v9fs_vfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir, 


/**

 * v9fs_vfs_getattr - retrieve file metadata

 * @mnt_userns: The user namespace of the mount

 * @idmap: idmap of the mount

 * @path: Object to query

 * @stat: metadata structure to populate

 * @request_mask: Mask of STATX_xxx flags indicating the caller's interests
@@ -1027,7 +1027,7 @@ v9fs_vfs_rename(struct user_namespace *mnt_userns, struct inode *old_dir, 
 */



static int

v9fs_vfs_getattr(struct user_namespace *mnt_userns, const struct path *path,

v9fs_vfs_getattr(struct mnt_idmap *idmap, const struct path *path,

		 struct kstat *stat, u32 request_mask, unsigned int flags)

{

	struct dentry *dentry = path->dentry;
@@ -1038,7 +1038,7 @@ v9fs_vfs_getattr(struct user_namespace *mnt_userns, const struct path *path, 
	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);

	v9ses = v9fs_dentry2v9ses(dentry);

	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {

		generic_fillattr(&init_user_ns, d_inode(dentry), stat);

		generic_fillattr(&nop_mnt_idmap, d_inode(dentry), stat);

		return 0;

	}

	fid = v9fs_fid_lookup(dentry);
@@ -1051,7 +1051,7 @@ v9fs_vfs_getattr(struct user_namespace *mnt_userns, const struct path *path, 
		return PTR_ERR(st);



	v9fs_stat2inode(st, d_inode(dentry), dentry->d_sb, 0);

	generic_fillattr(&init_user_ns, d_inode(dentry), stat);

	generic_fillattr(&nop_mnt_idmap, d_inode(dentry), stat);



	p9stat_free(st);

	kfree(st);

fs/9p/vfs_inode_dotl.c

+3 −3
Original line number Diff line number Diff line
@@ -450,7 +450,7 @@ static int v9fs_vfs_mkdir_dotl(struct user_namespace *mnt_userns, 
}



static int

v9fs_vfs_getattr_dotl(struct user_namespace *mnt_userns,

v9fs_vfs_getattr_dotl(struct mnt_idmap *idmap,

		      const struct path *path, struct kstat *stat,

		      u32 request_mask, unsigned int flags)

{
@@ -462,7 +462,7 @@ v9fs_vfs_getattr_dotl(struct user_namespace *mnt_userns, 
	p9_debug(P9_DEBUG_VFS, "dentry: %p\n", dentry);

	v9ses = v9fs_dentry2v9ses(dentry);

	if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) {

		generic_fillattr(&init_user_ns, d_inode(dentry), stat);

		generic_fillattr(&nop_mnt_idmap, d_inode(dentry), stat);

		return 0;

	}

	fid = v9fs_fid_lookup(dentry);
@@ -479,7 +479,7 @@ v9fs_vfs_getattr_dotl(struct user_namespace *mnt_userns, 
		return PTR_ERR(st);



	v9fs_stat2inode_dotl(st, d_inode(dentry), 0);

	generic_fillattr(&init_user_ns, d_inode(dentry), stat);

	generic_fillattr(&nop_mnt_idmap, d_inode(dentry), stat);

	/* Change block size to what the server returned */

	stat->blksize = st->st_blksize;

fs/afs/inode.c

+2 −2
Original line number Diff line number Diff line
@@ -737,7 +737,7 @@ int afs_validate(struct afs_vnode *vnode, struct key *key) 
/*

 * read the attributes of an inode

 */

int afs_getattr(struct user_namespace *mnt_userns, const struct path *path,

int afs_getattr(struct mnt_idmap *idmap, const struct path *path,

		struct kstat *stat, u32 request_mask, unsigned int query_flags)

{

	struct inode *inode = d_inode(path->dentry);
@@ -761,7 +761,7 @@ int afs_getattr(struct user_namespace *mnt_userns, const struct path *path, 


	do {

		read_seqbegin_or_lock(&vnode->cb_lock, &seq);

		generic_fillattr(&init_user_ns, inode, stat);

		generic_fillattr(&nop_mnt_idmap, inode, stat);

		if (test_bit(AFS_VNODE_SILLY_DELETED, &vnode->flags) &&

		    stat->nlink > 0)

			stat->nlink -= 1;