NFSD: drop support for ancient filehandles

Filehandles not in the "new" or "version 1" format have not been handed
out for new mounts since Linux 2.4 which was released 20 years ago.
I think it is safe to say that no such file handles are still in use,
and that we can drop support for them.

Signed-off-by: NeilBrown <[email protected]>
Signed-off-by: J. Bruce Fields <[email protected]>

Author: neilbrown

fs/nfsd/nfsfh.c

@@ -154,11 +154,12 @@ static inline __be32 check_pseudo_root(struct svc_rqst *rqstp,
 static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp)
 {
 	struct knfsd_fh	*fh = &fhp->fh_handle;
-	struct fid *fid = NULL, sfid;
+	struct fid *fid = NULL;
 	struct svc_export *exp;
 	struct dentry *dentry;
 	int fileid_type;
 	int data_left = fh->fh_size/4;
+	int len;
 	__be32 error;
 
 	error = nfserr_stale;
@@ -167,48 +168,35 @@ static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp)
 	if (rqstp->rq_vers == 4 && fh->fh_size == 0)
 		return nfserr_nofilehandle;
 
-	if (fh->fh_version == 1) {
-		int len;
-
-		if (--data_left < 0)
-			return error;
-		if (fh->fh_auth_type != 0)
-			return error;
-		len = key_len(fh->fh_fsid_type) / 4;
-		if (len == 0)
-			return error;
-		if  (fh->fh_fsid_type == FSID_MAJOR_MINOR) {
-			/* deprecated, convert to type 3 */
-			len = key_len(FSID_ENCODE_DEV)/4;
-			fh->fh_fsid_type = FSID_ENCODE_DEV;
-			/*
-			 * struct knfsd_fh uses host-endian fields, which are
-			 * sometimes used to hold net-endian values. This
-			 * confuses sparse, so we must use __force here to
-			 * keep it from complaining.
-			 */
-			fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl((__force __be32)fh->fh_fsid[0]),
-							ntohl((__force __be32)fh->fh_fsid[1])));
-			fh->fh_fsid[1] = fh->fh_fsid[2];
-		}
-		data_left -= len;
-		if (data_left < 0)
-			return error;
-		exp = rqst_exp_find(rqstp, fh->fh_fsid_type, fh->fh_fsid);
-		fid = (struct fid *)(fh->fh_fsid + len);
-	} else {
-		__u32 tfh[2];
-		dev_t xdev;
-		ino_t xino;
-
-		if (fh->fh_size != NFS_FHSIZE)
-			return error;
-		/* assume old filehandle format */
-		xdev = old_decode_dev(fh->ofh_xdev);
-		xino = u32_to_ino_t(fh->ofh_xino);
-		mk_fsid(FSID_DEV, tfh, xdev, xino, 0, NULL);
-		exp = rqst_exp_find(rqstp, FSID_DEV, tfh);
+	if (fh->fh_version != 1)
+		return error;
+
+	if (--data_left < 0)
+		return error;
+	if (fh->fh_auth_type != 0)
+		return error;
+	len = key_len(fh->fh_fsid_type) / 4;
+	if (len == 0)
+		return error;
+	if (fh->fh_fsid_type == FSID_MAJOR_MINOR) {
+		/* deprecated, convert to type 3 */
+		len = key_len(FSID_ENCODE_DEV)/4;
+		fh->fh_fsid_type = FSID_ENCODE_DEV;
+		/*
+		 * struct knfsd_fh uses host-endian fields, which are
+		 * sometimes used to hold net-endian values. This
+		 * confuses sparse, so we must use __force here to
+		 * keep it from complaining.
+		 */
+		fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl((__force __be32)fh->fh_fsid[0]),
+						      ntohl((__force __be32)fh->fh_fsid[1])));
+		fh->fh_fsid[1] = fh->fh_fsid[2];
 	}
+	data_left -= len;
+	if (data_left < 0)
+		return error;
+	exp = rqst_exp_find(rqstp, fh->fh_fsid_type, fh->fh_fsid);
+	fid = (struct fid *)(fh->fh_fsid + len);
 
 	error = nfserr_stale;
 	if (IS_ERR(exp)) {
@@ -253,18 +241,7 @@ static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp)
 	if (rqstp->rq_vers > 2)
 		error = nfserr_badhandle;
 
-	if (fh->fh_version != 1) {
-		sfid.i32.ino = fh->ofh_ino;
-		sfid.i32.gen = fh->ofh_generation;
-		sfid.i32.parent_ino = fh->ofh_dirino;
-		fid = &sfid;
-		data_left = 3;
-		if (fh->ofh_dirino == 0)
-			fileid_type = FILEID_INO32_GEN;
-		else
-			fileid_type = FILEID_INO32_GEN_PARENT;
-	} else
-		fileid_type = fh->fh_fileid_type;
+	fileid_type = fh->fh_fileid_type;
 
 	if (fileid_type == FILEID_ROOT)
 		dentry = dget(exp->ex_path.dentry);
@@ -452,20 +429,6 @@ static void _fh_update(struct svc_fh *fhp, struct svc_export *exp,
 	}
 }
 
-/*
- * for composing old style file handles
- */
-static inline void _fh_update_old(struct dentry *dentry,
-				  struct svc_export *exp,
-				  struct knfsd_fh *fh)
-{
-	fh->ofh_ino = ino_t_to_u32(d_inode(dentry)->i_ino);
-	fh->ofh_generation = d_inode(dentry)->i_generation;
-	if (d_is_dir(dentry) ||
-	    (exp->ex_flags & NFSEXP_NOSUBTREECHECK))
-		fh->ofh_dirino = 0;
-}
-
 static bool is_root_export(struct svc_export *exp)
 {
 	return exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root;
@@ -562,9 +525,6 @@ fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry,
 	/* ref_fh is a reference file handle.
 	 * if it is non-null and for the same filesystem, then we should compose
 	 * a filehandle which is of the same version, where possible.
-	 * Currently, that means that if ref_fh->fh_handle.fh_version == 0xca
-	 * Then create a 32byte filehandle using nfs_fhbase_old
-	 *
 	 */
 
 	struct inode * inode = d_inode(dentry);
@@ -600,35 +560,21 @@ fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry,
 	fhp->fh_dentry = dget(dentry); /* our internal copy */
 	fhp->fh_export = exp_get(exp);
 
-	if (fhp->fh_handle.fh_version == 0xca) {
-		/* old style filehandle please */
-		memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE);
-		fhp->fh_handle.fh_size = NFS_FHSIZE;
-		fhp->fh_handle.ofh_dcookie = 0xfeebbaca;
-		fhp->fh_handle.ofh_dev =  old_encode_dev(ex_dev);
-		fhp->fh_handle.ofh_xdev = fhp->fh_handle.ofh_dev;
-		fhp->fh_handle.ofh_xino =
-			ino_t_to_u32(d_inode(exp->ex_path.dentry)->i_ino);
-		fhp->fh_handle.ofh_dirino = ino_t_to_u32(parent_ino(dentry));
-		if (inode)
-			_fh_update_old(dentry, exp, &fhp->fh_handle);
-	} else {
-		fhp->fh_handle.fh_size =
-			key_len(fhp->fh_handle.fh_fsid_type) + 4;
-		fhp->fh_handle.fh_auth_type = 0;
-
-		mk_fsid(fhp->fh_handle.fh_fsid_type,
-			fhp->fh_handle.fh_fsid,
-			ex_dev,
-			d_inode(exp->ex_path.dentry)->i_ino,
-			exp->ex_fsid, exp->ex_uuid);
-
-		if (inode)
-			_fh_update(fhp, exp, dentry);
-		if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID) {
-			fh_put(fhp);
-			return nfserr_opnotsupp;
-		}
+	fhp->fh_handle.fh_size =
+		key_len(fhp->fh_handle.fh_fsid_type) + 4;
+	fhp->fh_handle.fh_auth_type = 0;
+
+	mk_fsid(fhp->fh_handle.fh_fsid_type,
+		fhp->fh_handle.fh_fsid,
+		ex_dev,
+		d_inode(exp->ex_path.dentry)->i_ino,
+		exp->ex_fsid, exp->ex_uuid);
+
+	if (inode)
+		_fh_update(fhp, exp, dentry);
+	if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID) {
+		fh_put(fhp);
+		return nfserr_opnotsupp;
 	}
 
 	return 0;
@@ -649,16 +595,12 @@ fh_update(struct svc_fh *fhp)
 	dentry = fhp->fh_dentry;
 	if (d_really_is_negative(dentry))
 		goto out_negative;
-	if (fhp->fh_handle.fh_version != 1) {
-		_fh_update_old(dentry, fhp->fh_export, &fhp->fh_handle);
-	} else {
-		if (fhp->fh_handle.fh_fileid_type != FILEID_ROOT)
-			return 0;
+	if (fhp->fh_handle.fh_fileid_type != FILEID_ROOT)
+		return 0;
 
-		_fh_update(fhp, fhp->fh_export, dentry);
-		if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID)
-			return nfserr_opnotsupp;
-	}
+	_fh_update(fhp, fhp->fh_export, dentry);
+	if (fhp->fh_handle.fh_fileid_type == FILEID_INVALID)
+		return nfserr_opnotsupp;
 	return 0;
 out_bad:
 	printk(KERN_ERR "fh_update: fh not verified!\n");

fs/nfsd/nfsfh.h

@@ -14,26 +14,7 @@
 #include <linux/exportfs.h>
 #include <linux/nfs4.h>
 
-
-/*
- * This is the old "dentry style" Linux NFSv2 file handle.
- *
- * The xino and xdev fields are currently used to transport the
- * ino/dev of the exported inode.
- */
-struct nfs_fhbase_old {
-	u32		fb_dcookie;	/* dentry cookie - always 0xfeebbaca */
-	u32		fb_ino;		/* our inode number */
-	u32		fb_dirino;	/* dir inode number, 0 for directories */
-	u32		fb_dev;		/* our device */
-	u32		fb_xdev;
-	u32		fb_xino;
-	u32		fb_generation;
-};
-
 /*
- * This is the new flexible, extensible style NFSv2/v3/v4 file handle.
- *
  * The file handle starts with a sequence of four-byte words.
  * The first word contains a version number (1) and three descriptor bytes
  * that tell how the remaining 3 variable length fields should be handled.
@@ -57,15 +38,15 @@ struct nfs_fhbase_old {
  *     6  - 16 byte uuid
  *     7  - 8 byte inode number and 16 byte uuid
  *
- * The fileid_type identified how the file within the filesystem is encoded.
+ * The fileid_type identifies how the file within the filesystem is encoded.
  *   The values for this field are filesystem specific, exccept that
  *   filesystems must not use the values '0' or '0xff'. 'See enum fid_type'
  *   in include/linux/exportfs.h for currently registered values.
  */
 struct nfs_fhbase_new {
 	union {
 		struct {
-			u8		fb_version_aux;	/* == 1, even => nfs_fhbase_old */
+			u8		fb_version_aux;	/* == 1 */
 			u8		fb_auth_type_aux;
 			u8		fb_fsid_type_aux;
 			u8		fb_fileid_type_aux;
@@ -74,7 +55,7 @@ struct nfs_fhbase_new {
 		/*	u32		fb_fileid[0]; floating */
 		};
 		struct {
-			u8		fb_version;	/* == 1, even => nfs_fhbase_old */
+			u8		fb_version;	/* == 1 */
 			u8		fb_auth_type;
 			u8		fb_fsid_type;
 			u8		fb_fileid_type;
@@ -89,20 +70,11 @@ struct knfsd_fh {
 					 * a new file handle
 					 */
 	union {
-		struct nfs_fhbase_old	fh_old;
 		u32			fh_pad[NFS4_FHSIZE/4];
 		struct nfs_fhbase_new	fh_new;
 	} fh_base;
 };
 
-#define ofh_dcookie		fh_base.fh_old.fb_dcookie
-#define ofh_ino			fh_base.fh_old.fb_ino
-#define ofh_dirino		fh_base.fh_old.fb_dirino
-#define ofh_dev			fh_base.fh_old.fb_dev
-#define ofh_xdev		fh_base.fh_old.fb_xdev
-#define ofh_xino		fh_base.fh_old.fb_xino
-#define ofh_generation		fh_base.fh_old.fb_generation
-
 #define	fh_version		fh_base.fh_new.fb_version
 #define	fh_fsid_type		fh_base.fh_new.fb_fsid_type
 #define	fh_auth_type		fh_base.fh_new.fb_auth_type