diff mbox series

[1/2,v2] NFSD: drop support for ancient filehandles

Message ID 163038488360.7591.7865010833762169362@noble.neil.brown.name (mailing list archive)
State New, archived
Headers show
Series [1/2,v2] NFSD: drop support for ancient filehandles | expand

Commit Message

NeilBrown Aug. 31, 2021, 4:41 a.m. UTC
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.

This patch also moves the nfs_fh.h (with old-format filehandle
information removed) from the include/uapi directory into fs/nfsd.  I
can find no evidence of it being used anywhere outside the kernel.
Certainly nfs-utils and wireshark do not use it.

As these declarations are no longer in 'uapi' we can use the 'u8' style
of integer type rather than '__u8'.

Signed-off-by: NeilBrown <neilb@suse.de>
---
 fs/nfsd/nfsfh.c                 | 157 +++++++++++---------------------
 fs/nfsd/nfsfh.h                 |  69 +++++++++++++-
 include/uapi/linux/nfsd/nfsfh.h | 116 -----------------------
 3 files changed, 119 insertions(+), 223 deletions(-)
 delete mode 100644 include/uapi/linux/nfsd/nfsfh.h

Comments

Christoph Hellwig Sept. 1, 2021, 7:44 a.m. UTC | #1
The content looks fine, but I still think moving the definition out of
the uapi and removing the ancient file handles are different things
that should be separate patches with separate commit logs explaining
the story.
Chuck Lever Sept. 1, 2021, 2:21 p.m. UTC | #2
> On Sep 1, 2021, at 3:44 AM, Christoph Hellwig <hch@lst.de> wrote:
> 
> The content looks fine, but I still think moving the definition out of
> the uapi and removing the ancient file handles are different things
> that should be separate patches with separate commit logs explaining
> the story.

Was thinking the same thing when looking at v1 of this patch set.
Neil, it's a nit, of course, but would you split this patch up,
please and thanks?

--
Chuck Lever
diff mbox series

Patch

diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c
index c475d2271f9c..9194a940b23d 100644
--- a/fs/nfsd/nfsfh.c
+++ b/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;
@@ -600,35 +563,21 @@  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 +598,12 @@  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");
diff --git a/fs/nfsd/nfsfh.h b/fs/nfsd/nfsfh.h
index 6106697adc04..17fc6f57d1bb 100644
--- a/fs/nfsd/nfsfh.h
+++ b/fs/nfsd/nfsfh.h
@@ -10,9 +10,76 @@ 
 
 #include <linux/crc32.h>
 #include <linux/sunrpc/svc.h>
-#include <uapi/linux/nfsd/nfsfh.h>
 #include <linux/iversion.h>
 #include <linux/exportfs.h>
+#include <linux/nfs4.h>
+
+/*
+ * 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.
+ * These three bytes are auth_type, fsid_type and fileid_type.
+ *
+ * All four-byte values are in host-byte-order.
+ *
+ * The auth_type field is deprecated and must be set to 0.
+ *
+ * The fsid_type identifies how the filesystem (or export point) is
+ *    encoded.
+ *  Current values:
+ *     0  - 4 byte device id (ms-2-bytes major, ls-2-bytes minor), 4byte inode number
+ *        NOTE: we cannot use the kdev_t device id value, because kdev_t.h
+ *              says we mustn't.  We must break it up and reassemble.
+ *     1  - 4 byte user specified identifier
+ *     2  - 4 byte major, 4 byte minor, 4 byte inode number - DEPRECATED
+ *     3  - 4 byte device id, encoded for user-space, 4 byte inode number
+ *     4  - 4 byte inode number and 4 byte uuid
+ *     5  - 8 byte uuid
+ *     6  - 16 byte uuid
+ *     7  - 8 byte inode number and 16 byte uuid
+ *
+ * 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_auth_type_aux;
+			u8		fb_fsid_type_aux;
+			u8		fb_fileid_type_aux;
+			u32		fb_auth[1];
+		/*	u32		fb_fsid[0]; floating */
+		/*	u32		fb_fileid[0]; floating */
+		};
+		struct {
+			u8		fb_version;	/* == 1, even => nfs_fhbase_old */
+			u8		fb_auth_type;
+			u8		fb_fsid_type;
+			u8		fb_fileid_type;
+			u32		fb_auth_flex[]; /* flexible-array member */
+		};
+	};
+};
+
+struct knfsd_fh {
+	unsigned int	fh_size;	/* significant for NFSv3.
+					 * Points to the current size while building
+					 * a new file handle
+					 */
+	union {
+		u32			fh_pad[NFS4_FHSIZE/4];
+		struct nfs_fhbase_new	fh_new;
+	} fh_base;
+};
+
+#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
+#define	fh_fileid_type		fh_base.fh_new.fb_fileid_type
+#define	fh_fsid			fh_base.fh_new.fb_auth_flex
 
 static inline __u32 ino_t_to_u32(ino_t ino)
 {
diff --git a/include/uapi/linux/nfsd/nfsfh.h b/include/uapi/linux/nfsd/nfsfh.h
deleted file mode 100644
index 427294dd56a1..000000000000
--- a/include/uapi/linux/nfsd/nfsfh.h
+++ /dev/null
@@ -1,116 +0,0 @@ 
-/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
-/*
- * This file describes the layout of the file handles as passed
- * over the wire.
- *
- * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
- */
-
-#ifndef _UAPI_LINUX_NFSD_FH_H
-#define _UAPI_LINUX_NFSD_FH_H
-
-#include <linux/types.h>
-#include <linux/nfs.h>
-#include <linux/nfs2.h>
-#include <linux/nfs3.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.
- * by Neil Brown <neilb@cse.unsw.edu.au> - March 2000
- *
- * 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.
- * These three bytes are auth_type, fsid_type and fileid_type.
- *
- * All four-byte values are in host-byte-order.
- *
- * The auth_type field is deprecated and must be set to 0.
- *
- * The fsid_type identifies how the filesystem (or export point) is
- *    encoded.
- *  Current values:
- *     0  - 4 byte device id (ms-2-bytes major, ls-2-bytes minor), 4byte inode number
- *        NOTE: we cannot use the kdev_t device id value, because kdev_t.h
- *              says we mustn't.  We must break it up and reassemble.
- *     1  - 4 byte user specified identifier
- *     2  - 4 byte major, 4 byte minor, 4 byte inode number - DEPRECATED
- *     3  - 4 byte device id, encoded for user-space, 4 byte inode number
- *     4  - 4 byte inode number and 4 byte uuid
- *     5  - 8 byte uuid
- *     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 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_auth_type_aux;
-			__u8		fb_fsid_type_aux;
-			__u8		fb_fileid_type_aux;
-			__u32		fb_auth[1];
-			/*	__u32		fb_fsid[0]; floating */
-			/*	__u32		fb_fileid[0]; floating */
-		};
-		struct {
-			__u8		fb_version;	/* == 1, even => nfs_fhbase_old */
-			__u8		fb_auth_type;
-			__u8		fb_fsid_type;
-			__u8		fb_fileid_type;
-			__u32		fb_auth_flex[]; /* flexible-array member */
-		};
-	};
-};
-
-struct knfsd_fh {
-	unsigned int	fh_size;	/* significant for NFSv3.
-					 * Points to the current size while building
-					 * 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
-#define	fh_fileid_type		fh_base.fh_new.fb_fileid_type
-#define	fh_fsid			fh_base.fh_new.fb_auth_flex
-
-/* Do not use, provided for userspace compatiblity. */
-#define	fh_auth			fh_base.fh_new.fb_auth
-
-#endif /* _UAPI_LINUX_NFSD_FH_H */