From e21fc2038c1b978b89bbc3d45a4c5c6ef598e178 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Mon, 23 Oct 2023 21:07:59 +0300 Subject: [PATCH] exportfs: make ->encode_fh() a mandatory method for NFS export Rename the default helper for encoding FILEID_INO32_GEN* file handles to generic_encode_ino32_fh() and convert the filesystems that used the default implementation to use the generic helper explicitly. After this change, exportfs_encode_inode_fh() no longer has a default implementation to encode FILEID_INO32_GEN* file handles. This is a step towards allowing filesystems to encode non-decodeable file handles for fanotify without having to implement any export_operations. Reviewed-by: Jan Kara Reviewed-by: Jeff Layton Acked-by: Chuck Lever Signed-off-by: Amir Goldstein Link: https://lore.kernel.org/r/20231023180801.2953446-3-amir73il@gmail.com Acked-by: Dave Kleikamp Reviewed-by: Christoph Hellwig Signed-off-by: Christian Brauner --- Documentation/filesystems/nfs/exporting.rst | 7 ++----- Documentation/filesystems/porting.rst | 9 +++++++++ fs/affs/namei.c | 1 + fs/befs/linuxvfs.c | 1 + fs/efs/super.c | 1 + fs/erofs/super.c | 1 + fs/exportfs/expfs.c | 16 +++++++++------- fs/ext2/super.c | 1 + fs/ext4/super.c | 1 + fs/f2fs/super.c | 1 + fs/fat/nfs.c | 1 + fs/jffs2/super.c | 1 + fs/jfs/super.c | 1 + fs/ntfs/namei.c | 1 + fs/ntfs3/super.c | 1 + fs/smb/client/export.c | 11 +++++------ fs/squashfs/export.c | 1 + fs/ufs/super.c | 1 + include/linux/exportfs.h | 9 ++++++++- 19 files changed, 47 insertions(+), 19 deletions(-) diff --git a/Documentation/filesystems/nfs/exporting.rst b/Documentation/filesystems/nfs/exporting.rst index 4b30daee399a..de64d2d002a2 100644 --- a/Documentation/filesystems/nfs/exporting.rst +++ b/Documentation/filesystems/nfs/exporting.rst @@ -122,12 +122,9 @@ are exportable by setting the s_export_op field in the struct super_block. This field must point to a "struct export_operations" struct which has the following members: - encode_fh (optional) + encode_fh (mandatory) Takes a dentry and creates a filehandle fragment which may later be used - to find or create a dentry for the same object. The default - implementation creates a filehandle fragment that encodes a 32bit inode - and generation number for the inode encoded, and if necessary the - same information for the parent. + to find or create a dentry for the same object. fh_to_dentry (mandatory) Given a filehandle fragment, this should find the implied object and diff --git a/Documentation/filesystems/porting.rst b/Documentation/filesystems/porting.rst index 4d05b9862451..9cc6cb27c4d5 100644 --- a/Documentation/filesystems/porting.rst +++ b/Documentation/filesystems/porting.rst @@ -1045,3 +1045,12 @@ filesystem type is now moved to a later point when the devices are closed: As this is a VFS level change it has no practical consequences for filesystems other than that all of them must use one of the provided kill_litter_super(), kill_anon_super(), or kill_block_super() helpers. + +--- + +**mandatory** + +export_operations ->encode_fh() no longer has a default implementation to +encode FILEID_INO32_GEN* file handles. +Filesystems that used the default implementation may use the generic helper +generic_encode_ino32_fh() explicitly. diff --git a/fs/affs/namei.c b/fs/affs/namei.c index 2fe4a5832fcf..d6b9758ee23d 100644 --- a/fs/affs/namei.c +++ b/fs/affs/namei.c @@ -568,6 +568,7 @@ static struct dentry *affs_fh_to_parent(struct super_block *sb, struct fid *fid, } const struct export_operations affs_export_ops = { + .encode_fh = generic_encode_ino32_fh, .fh_to_dentry = affs_fh_to_dentry, .fh_to_parent = affs_fh_to_parent, .get_parent = affs_get_parent, diff --git a/fs/befs/linuxvfs.c b/fs/befs/linuxvfs.c index 9a16a51fbb88..410dcaffd5ab 100644 --- a/fs/befs/linuxvfs.c +++ b/fs/befs/linuxvfs.c @@ -96,6 +96,7 @@ static const struct address_space_operations befs_symlink_aops = { }; static const struct export_operations befs_export_operations = { + .encode_fh = generic_encode_ino32_fh, .fh_to_dentry = befs_fh_to_dentry, .fh_to_parent = befs_fh_to_parent, .get_parent = befs_get_parent, diff --git a/fs/efs/super.c b/fs/efs/super.c index b287f47c165b..f17fdac76b2e 100644 --- a/fs/efs/super.c +++ b/fs/efs/super.c @@ -123,6 +123,7 @@ static const struct super_operations efs_superblock_operations = { }; static const struct export_operations efs_export_ops = { + .encode_fh = generic_encode_ino32_fh, .fh_to_dentry = efs_fh_to_dentry, .fh_to_parent = efs_fh_to_parent, .get_parent = efs_get_parent, diff --git a/fs/erofs/super.c b/fs/erofs/super.c index 3700af9ee173..edbe07a24156 100644 --- a/fs/erofs/super.c +++ b/fs/erofs/super.c @@ -626,6 +626,7 @@ static struct dentry *erofs_get_parent(struct dentry *child) } static const struct export_operations erofs_export_ops = { + .encode_fh = generic_encode_ino32_fh, .fh_to_dentry = erofs_fh_to_dentry, .fh_to_parent = erofs_fh_to_parent, .get_parent = erofs_get_parent, diff --git a/fs/exportfs/expfs.c b/fs/exportfs/expfs.c index 9ee205df8fa7..8f883c4758f5 100644 --- a/fs/exportfs/expfs.c +++ b/fs/exportfs/expfs.c @@ -343,20 +343,21 @@ out: } /** - * export_encode_fh - default export_operations->encode_fh function + * generic_encode_ino32_fh - generic export_operations->encode_fh function * @inode: the object to encode - * @fid: where to store the file handle fragment - * @max_len: maximum length to store there + * @fh: where to store the file handle fragment + * @max_len: maximum length to store there (in 4 byte units) * @parent: parent directory inode, if wanted * - * This default encode_fh function assumes that the 32 inode number + * This generic encode_fh function assumes that the 32 inode number * is suitable for locating an inode, and that the generation number * can be used to check that it is still valid. It places them in the * filehandle fragment where export_decode_fh expects to find them. */ -static int export_encode_fh(struct inode *inode, struct fid *fid, - int *max_len, struct inode *parent) +int generic_encode_ino32_fh(struct inode *inode, __u32 *fh, int *max_len, + struct inode *parent) { + struct fid *fid = (void *)fh; int len = *max_len; int type = FILEID_INO32_GEN; @@ -380,6 +381,7 @@ static int export_encode_fh(struct inode *inode, struct fid *fid, *max_len = len; return type; } +EXPORT_SYMBOL_GPL(generic_encode_ino32_fh); /** * exportfs_encode_inode_fh - encode a file handle from inode @@ -402,7 +404,7 @@ int exportfs_encode_inode_fh(struct inode *inode, struct fid *fid, if (nop && nop->encode_fh) return nop->encode_fh(inode, fid->raw, max_len, parent); - return export_encode_fh(inode, fid, max_len, parent); + return -EOPNOTSUPP; } EXPORT_SYMBOL_GPL(exportfs_encode_inode_fh); diff --git a/fs/ext2/super.c b/fs/ext2/super.c index aaf3e3e88cb2..b9f158a34997 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -397,6 +397,7 @@ static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid, } static const struct export_operations ext2_export_ops = { + .encode_fh = generic_encode_ino32_fh, .fh_to_dentry = ext2_fh_to_dentry, .fh_to_parent = ext2_fh_to_parent, .get_parent = ext2_get_parent, diff --git a/fs/ext4/super.c b/fs/ext4/super.c index dbebd8b3127e..c44db1915437 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1646,6 +1646,7 @@ static const struct super_operations ext4_sops = { }; static const struct export_operations ext4_export_ops = { + .encode_fh = generic_encode_ino32_fh, .fh_to_dentry = ext4_fh_to_dentry, .fh_to_parent = ext4_fh_to_parent, .get_parent = ext4_get_parent, diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index a8c8232852bb..60cfa11f65bf 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -3282,6 +3282,7 @@ static struct dentry *f2fs_fh_to_parent(struct super_block *sb, struct fid *fid, } static const struct export_operations f2fs_export_ops = { + .encode_fh = generic_encode_ino32_fh, .fh_to_dentry = f2fs_fh_to_dentry, .fh_to_parent = f2fs_fh_to_parent, .get_parent = f2fs_get_parent, diff --git a/fs/fat/nfs.c b/fs/fat/nfs.c index 3626eb585a98..c52e63e10d35 100644 --- a/fs/fat/nfs.c +++ b/fs/fat/nfs.c @@ -279,6 +279,7 @@ static struct dentry *fat_get_parent(struct dentry *child_dir) } const struct export_operations fat_export_ops = { + .encode_fh = generic_encode_ino32_fh, .fh_to_dentry = fat_fh_to_dentry, .fh_to_parent = fat_fh_to_parent, .get_parent = fat_get_parent, diff --git a/fs/jffs2/super.c b/fs/jffs2/super.c index 7ea37f49f1e1..f99591a634b4 100644 --- a/fs/jffs2/super.c +++ b/fs/jffs2/super.c @@ -150,6 +150,7 @@ static struct dentry *jffs2_get_parent(struct dentry *child) } static const struct export_operations jffs2_export_ops = { + .encode_fh = generic_encode_ino32_fh, .get_parent = jffs2_get_parent, .fh_to_dentry = jffs2_fh_to_dentry, .fh_to_parent = jffs2_fh_to_parent, diff --git a/fs/jfs/super.c b/fs/jfs/super.c index 2e2f7f6d36a0..2cc2632f3c47 100644 --- a/fs/jfs/super.c +++ b/fs/jfs/super.c @@ -896,6 +896,7 @@ static const struct super_operations jfs_super_operations = { }; static const struct export_operations jfs_export_operations = { + .encode_fh = generic_encode_ino32_fh, .fh_to_dentry = jfs_fh_to_dentry, .fh_to_parent = jfs_fh_to_parent, .get_parent = jfs_get_parent, diff --git a/fs/ntfs/namei.c b/fs/ntfs/namei.c index ab44f2db533b..d7498ddc4a72 100644 --- a/fs/ntfs/namei.c +++ b/fs/ntfs/namei.c @@ -384,6 +384,7 @@ static struct dentry *ntfs_fh_to_parent(struct super_block *sb, struct fid *fid, * and due to using iget() whereas NTFS needs ntfs_iget(). */ const struct export_operations ntfs_export_ops = { + .encode_fh = generic_encode_ino32_fh, .get_parent = ntfs_get_parent, /* Find the parent of a given directory. */ .fh_to_dentry = ntfs_fh_to_dentry, diff --git a/fs/ntfs3/super.c b/fs/ntfs3/super.c index f763e3256ccc..9153dffde950 100644 --- a/fs/ntfs3/super.c +++ b/fs/ntfs3/super.c @@ -811,6 +811,7 @@ static int ntfs_nfs_commit_metadata(struct inode *inode) } static const struct export_operations ntfs_export_ops = { + .encode_fh = generic_encode_ino32_fh, .fh_to_dentry = ntfs_fh_to_dentry, .fh_to_parent = ntfs_fh_to_parent, .get_parent = ntfs3_get_parent, diff --git a/fs/smb/client/export.c b/fs/smb/client/export.c index 37c28415df1e..d606e8cbcb7d 100644 --- a/fs/smb/client/export.c +++ b/fs/smb/client/export.c @@ -41,13 +41,12 @@ static struct dentry *cifs_get_parent(struct dentry *dentry) } const struct export_operations cifs_export_ops = { + .encode_fh = generic_encode_ino32_fh, .get_parent = cifs_get_parent, -/* Following five export operations are unneeded so far and can default: - .get_dentry = - .get_name = - .find_exported_dentry = - .decode_fh = - .encode_fs = */ +/* + * Following export operations are mandatory for NFS export support: + * .fh_to_dentry = + */ }; #endif /* CONFIG_CIFS_NFSD_EXPORT */ diff --git a/fs/squashfs/export.c b/fs/squashfs/export.c index 723763746238..62972f0ff868 100644 --- a/fs/squashfs/export.c +++ b/fs/squashfs/export.c @@ -173,6 +173,7 @@ __le64 *squashfs_read_inode_lookup_table(struct super_block *sb, const struct export_operations squashfs_export_ops = { + .encode_fh = generic_encode_ino32_fh, .fh_to_dentry = squashfs_fh_to_dentry, .fh_to_parent = squashfs_fh_to_parent, .get_parent = squashfs_get_parent diff --git a/fs/ufs/super.c b/fs/ufs/super.c index 23377c1baed9..a480810cd4e3 100644 --- a/fs/ufs/super.c +++ b/fs/ufs/super.c @@ -137,6 +137,7 @@ static struct dentry *ufs_get_parent(struct dentry *child) } static const struct export_operations ufs_export_ops = { + .encode_fh = generic_encode_ino32_fh, .fh_to_dentry = ufs_fh_to_dentry, .fh_to_parent = ufs_fh_to_parent, .get_parent = ufs_get_parent, diff --git a/include/linux/exportfs.h b/include/linux/exportfs.h index 5b3c9f30b422..85bd027494e5 100644 --- a/include/linux/exportfs.h +++ b/include/linux/exportfs.h @@ -235,7 +235,7 @@ extern int exportfs_encode_fh(struct dentry *dentry, struct fid *fid, static inline bool exportfs_can_encode_fid(const struct export_operations *nop) { - return nop; + return nop && nop->encode_fh; } static inline bool exportfs_can_decode_fh(const struct export_operations *nop) @@ -279,6 +279,13 @@ extern struct dentry *exportfs_decode_fh(struct vfsmount *mnt, struct fid *fid, /* * Generic helpers for filesystems. */ +#ifdef CONFIG_EXPORTFS +int generic_encode_ino32_fh(struct inode *inode, __u32 *fh, int *max_len, + struct inode *parent); +#else +#define generic_encode_ino32_fh NULL +#endif + extern struct dentry *generic_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len, int fh_type, struct inode *(*get_inode) (struct super_block *sb, u64 ino, u32 gen));