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-rw-r--r--fs/nfs/nfs2xdr.c1156
1 files changed, 1156 insertions, 0 deletions
diff --git a/fs/nfs/nfs2xdr.c b/fs/nfs/nfs2xdr.c
new file mode 100644
index 0000000000..c190938142
--- /dev/null
+++ b/fs/nfs/nfs2xdr.c
@@ -0,0 +1,1156 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * linux/fs/nfs/nfs2xdr.c
+ *
+ * XDR functions to encode/decode NFS RPC arguments and results.
+ *
+ * Copyright (C) 1992, 1993, 1994 Rick Sladkey
+ * Copyright (C) 1996 Olaf Kirch
+ * 04 Aug 1998 Ion Badulescu <ionut@cs.columbia.edu>
+ * FIFO's need special handling in NFSv2
+ */
+
+#include <linux/param.h>
+#include <linux/time.h>
+#include <linux/mm.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/in.h>
+#include <linux/pagemap.h>
+#include <linux/proc_fs.h>
+#include <linux/sunrpc/clnt.h>
+#include <linux/nfs.h>
+#include <linux/nfs2.h>
+#include <linux/nfs_fs.h>
+#include "nfstrace.h"
+#include "internal.h"
+
+#define NFSDBG_FACILITY NFSDBG_XDR
+
+/* Mapping from NFS error code to "errno" error code. */
+#define errno_NFSERR_IO EIO
+
+/*
+ * Declare the space requirements for NFS arguments and replies as
+ * number of 32bit-words
+ */
+#define NFS_pagepad_sz (1) /* Page padding */
+#define NFS_fhandle_sz (8)
+#define NFS_sattr_sz (8)
+#define NFS_filename_sz (1+(NFS2_MAXNAMLEN>>2))
+#define NFS_path_sz (1+(NFS2_MAXPATHLEN>>2))
+#define NFS_fattr_sz (17)
+#define NFS_info_sz (5)
+#define NFS_entry_sz (NFS_filename_sz+3)
+
+#define NFS_diropargs_sz (NFS_fhandle_sz+NFS_filename_sz)
+#define NFS_removeargs_sz (NFS_fhandle_sz+NFS_filename_sz)
+#define NFS_sattrargs_sz (NFS_fhandle_sz+NFS_sattr_sz)
+#define NFS_readlinkargs_sz (NFS_fhandle_sz)
+#define NFS_readargs_sz (NFS_fhandle_sz+3)
+#define NFS_writeargs_sz (NFS_fhandle_sz+4)
+#define NFS_createargs_sz (NFS_diropargs_sz+NFS_sattr_sz)
+#define NFS_renameargs_sz (NFS_diropargs_sz+NFS_diropargs_sz)
+#define NFS_linkargs_sz (NFS_fhandle_sz+NFS_diropargs_sz)
+#define NFS_symlinkargs_sz (NFS_diropargs_sz+1+NFS_sattr_sz)
+#define NFS_readdirargs_sz (NFS_fhandle_sz+2)
+
+#define NFS_attrstat_sz (1+NFS_fattr_sz)
+#define NFS_diropres_sz (1+NFS_fhandle_sz+NFS_fattr_sz)
+#define NFS_readlinkres_sz (2+NFS_pagepad_sz)
+#define NFS_readres_sz (1+NFS_fattr_sz+1+NFS_pagepad_sz)
+#define NFS_writeres_sz (NFS_attrstat_sz)
+#define NFS_stat_sz (1)
+#define NFS_readdirres_sz (1+NFS_pagepad_sz)
+#define NFS_statfsres_sz (1+NFS_info_sz)
+
+static int nfs_stat_to_errno(enum nfs_stat);
+
+/*
+ * Encode/decode NFSv2 basic data types
+ *
+ * Basic NFSv2 data types are defined in section 2.3 of RFC 1094:
+ * "NFS: Network File System Protocol Specification".
+ *
+ * Not all basic data types have their own encoding and decoding
+ * functions. For run-time efficiency, some data types are encoded
+ * or decoded inline.
+ */
+
+static struct user_namespace *rpc_userns(const struct rpc_clnt *clnt)
+{
+ if (clnt && clnt->cl_cred)
+ return clnt->cl_cred->user_ns;
+ return &init_user_ns;
+}
+
+static struct user_namespace *rpc_rqst_userns(const struct rpc_rqst *rqstp)
+{
+ if (rqstp->rq_task)
+ return rpc_userns(rqstp->rq_task->tk_client);
+ return &init_user_ns;
+}
+
+/*
+ * typedef opaque nfsdata<>;
+ */
+static int decode_nfsdata(struct xdr_stream *xdr, struct nfs_pgio_res *result)
+{
+ u32 recvd, count;
+ __be32 *p;
+
+ p = xdr_inline_decode(xdr, 4);
+ if (unlikely(!p))
+ return -EIO;
+ count = be32_to_cpup(p);
+ recvd = xdr_read_pages(xdr, count);
+ if (unlikely(count > recvd))
+ goto out_cheating;
+out:
+ result->eof = 0; /* NFSv2 does not pass EOF flag on the wire. */
+ result->count = count;
+ return count;
+out_cheating:
+ dprintk("NFS: server cheating in read result: "
+ "count %u > recvd %u\n", count, recvd);
+ count = recvd;
+ goto out;
+}
+
+/*
+ * enum stat {
+ * NFS_OK = 0,
+ * NFSERR_PERM = 1,
+ * NFSERR_NOENT = 2,
+ * NFSERR_IO = 5,
+ * NFSERR_NXIO = 6,
+ * NFSERR_ACCES = 13,
+ * NFSERR_EXIST = 17,
+ * NFSERR_NODEV = 19,
+ * NFSERR_NOTDIR = 20,
+ * NFSERR_ISDIR = 21,
+ * NFSERR_FBIG = 27,
+ * NFSERR_NOSPC = 28,
+ * NFSERR_ROFS = 30,
+ * NFSERR_NAMETOOLONG = 63,
+ * NFSERR_NOTEMPTY = 66,
+ * NFSERR_DQUOT = 69,
+ * NFSERR_STALE = 70,
+ * NFSERR_WFLUSH = 99
+ * };
+ */
+static int decode_stat(struct xdr_stream *xdr, enum nfs_stat *status)
+{
+ __be32 *p;
+
+ p = xdr_inline_decode(xdr, 4);
+ if (unlikely(!p))
+ return -EIO;
+ if (unlikely(*p != cpu_to_be32(NFS_OK)))
+ goto out_status;
+ *status = 0;
+ return 0;
+out_status:
+ *status = be32_to_cpup(p);
+ trace_nfs_xdr_status(xdr, (int)*status);
+ return 0;
+}
+
+/*
+ * 2.3.2. ftype
+ *
+ * enum ftype {
+ * NFNON = 0,
+ * NFREG = 1,
+ * NFDIR = 2,
+ * NFBLK = 3,
+ * NFCHR = 4,
+ * NFLNK = 5
+ * };
+ *
+ */
+static __be32 *xdr_decode_ftype(__be32 *p, u32 *type)
+{
+ *type = be32_to_cpup(p++);
+ if (unlikely(*type > NF2FIFO))
+ *type = NFBAD;
+ return p;
+}
+
+/*
+ * 2.3.3. fhandle
+ *
+ * typedef opaque fhandle[FHSIZE];
+ */
+static void encode_fhandle(struct xdr_stream *xdr, const struct nfs_fh *fh)
+{
+ __be32 *p;
+
+ p = xdr_reserve_space(xdr, NFS2_FHSIZE);
+ memcpy(p, fh->data, NFS2_FHSIZE);
+}
+
+static int decode_fhandle(struct xdr_stream *xdr, struct nfs_fh *fh)
+{
+ __be32 *p;
+
+ p = xdr_inline_decode(xdr, NFS2_FHSIZE);
+ if (unlikely(!p))
+ return -EIO;
+ fh->size = NFS2_FHSIZE;
+ memcpy(fh->data, p, NFS2_FHSIZE);
+ return 0;
+}
+
+/*
+ * 2.3.4. timeval
+ *
+ * struct timeval {
+ * unsigned int seconds;
+ * unsigned int useconds;
+ * };
+ */
+static __be32 *xdr_encode_time(__be32 *p, const struct timespec64 *timep)
+{
+ *p++ = cpu_to_be32((u32)timep->tv_sec);
+ if (timep->tv_nsec != 0)
+ *p++ = cpu_to_be32(timep->tv_nsec / NSEC_PER_USEC);
+ else
+ *p++ = cpu_to_be32(0);
+ return p;
+}
+
+/*
+ * Passing the invalid value useconds=1000000 is a Sun convention for
+ * "set to current server time". It's needed to make permissions checks
+ * for the "touch" program across v2 mounts to Solaris and Irix servers
+ * work correctly. See description of sattr in section 6.1 of "NFS
+ * Illustrated" by Brent Callaghan, Addison-Wesley, ISBN 0-201-32750-5.
+ */
+static __be32 *xdr_encode_current_server_time(__be32 *p,
+ const struct timespec64 *timep)
+{
+ *p++ = cpu_to_be32(timep->tv_sec);
+ *p++ = cpu_to_be32(1000000);
+ return p;
+}
+
+static __be32 *xdr_decode_time(__be32 *p, struct timespec64 *timep)
+{
+ timep->tv_sec = be32_to_cpup(p++);
+ timep->tv_nsec = be32_to_cpup(p++) * NSEC_PER_USEC;
+ return p;
+}
+
+/*
+ * 2.3.5. fattr
+ *
+ * struct fattr {
+ * ftype type;
+ * unsigned int mode;
+ * unsigned int nlink;
+ * unsigned int uid;
+ * unsigned int gid;
+ * unsigned int size;
+ * unsigned int blocksize;
+ * unsigned int rdev;
+ * unsigned int blocks;
+ * unsigned int fsid;
+ * unsigned int fileid;
+ * timeval atime;
+ * timeval mtime;
+ * timeval ctime;
+ * };
+ *
+ */
+static int decode_fattr(struct xdr_stream *xdr, struct nfs_fattr *fattr,
+ struct user_namespace *userns)
+{
+ u32 rdev, type;
+ __be32 *p;
+
+ p = xdr_inline_decode(xdr, NFS_fattr_sz << 2);
+ if (unlikely(!p))
+ return -EIO;
+
+ fattr->valid |= NFS_ATTR_FATTR_V2;
+
+ p = xdr_decode_ftype(p, &type);
+
+ fattr->mode = be32_to_cpup(p++);
+ fattr->nlink = be32_to_cpup(p++);
+ fattr->uid = make_kuid(userns, be32_to_cpup(p++));
+ if (!uid_valid(fattr->uid))
+ goto out_uid;
+ fattr->gid = make_kgid(userns, be32_to_cpup(p++));
+ if (!gid_valid(fattr->gid))
+ goto out_gid;
+
+ fattr->size = be32_to_cpup(p++);
+ fattr->du.nfs2.blocksize = be32_to_cpup(p++);
+
+ rdev = be32_to_cpup(p++);
+ fattr->rdev = new_decode_dev(rdev);
+ if (type == (u32)NFCHR && rdev == (u32)NFS2_FIFO_DEV) {
+ fattr->mode = (fattr->mode & ~S_IFMT) | S_IFIFO;
+ fattr->rdev = 0;
+ }
+
+ fattr->du.nfs2.blocks = be32_to_cpup(p++);
+ fattr->fsid.major = be32_to_cpup(p++);
+ fattr->fsid.minor = 0;
+ fattr->fileid = be32_to_cpup(p++);
+
+ p = xdr_decode_time(p, &fattr->atime);
+ p = xdr_decode_time(p, &fattr->mtime);
+ xdr_decode_time(p, &fattr->ctime);
+ fattr->change_attr = nfs_timespec_to_change_attr(&fattr->ctime);
+
+ return 0;
+out_uid:
+ dprintk("NFS: returned invalid uid\n");
+ return -EINVAL;
+out_gid:
+ dprintk("NFS: returned invalid gid\n");
+ return -EINVAL;
+}
+
+/*
+ * 2.3.6. sattr
+ *
+ * struct sattr {
+ * unsigned int mode;
+ * unsigned int uid;
+ * unsigned int gid;
+ * unsigned int size;
+ * timeval atime;
+ * timeval mtime;
+ * };
+ */
+
+#define NFS2_SATTR_NOT_SET (0xffffffff)
+
+static __be32 *xdr_time_not_set(__be32 *p)
+{
+ *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET);
+ *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET);
+ return p;
+}
+
+static void encode_sattr(struct xdr_stream *xdr, const struct iattr *attr,
+ struct user_namespace *userns)
+{
+ __be32 *p;
+
+ p = xdr_reserve_space(xdr, NFS_sattr_sz << 2);
+
+ if (attr->ia_valid & ATTR_MODE)
+ *p++ = cpu_to_be32(attr->ia_mode);
+ else
+ *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET);
+ if (attr->ia_valid & ATTR_UID)
+ *p++ = cpu_to_be32(from_kuid_munged(userns, attr->ia_uid));
+ else
+ *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET);
+ if (attr->ia_valid & ATTR_GID)
+ *p++ = cpu_to_be32(from_kgid_munged(userns, attr->ia_gid));
+ else
+ *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET);
+ if (attr->ia_valid & ATTR_SIZE)
+ *p++ = cpu_to_be32((u32)attr->ia_size);
+ else
+ *p++ = cpu_to_be32(NFS2_SATTR_NOT_SET);
+
+ if (attr->ia_valid & ATTR_ATIME_SET)
+ p = xdr_encode_time(p, &attr->ia_atime);
+ else if (attr->ia_valid & ATTR_ATIME)
+ p = xdr_encode_current_server_time(p, &attr->ia_atime);
+ else
+ p = xdr_time_not_set(p);
+ if (attr->ia_valid & ATTR_MTIME_SET)
+ xdr_encode_time(p, &attr->ia_mtime);
+ else if (attr->ia_valid & ATTR_MTIME)
+ xdr_encode_current_server_time(p, &attr->ia_mtime);
+ else
+ xdr_time_not_set(p);
+}
+
+/*
+ * 2.3.7. filename
+ *
+ * typedef string filename<MAXNAMLEN>;
+ */
+static void encode_filename(struct xdr_stream *xdr,
+ const char *name, u32 length)
+{
+ __be32 *p;
+
+ WARN_ON_ONCE(length > NFS2_MAXNAMLEN);
+ p = xdr_reserve_space(xdr, 4 + length);
+ xdr_encode_opaque(p, name, length);
+}
+
+static int decode_filename_inline(struct xdr_stream *xdr,
+ const char **name, u32 *length)
+{
+ __be32 *p;
+ u32 count;
+
+ p = xdr_inline_decode(xdr, 4);
+ if (unlikely(!p))
+ return -EIO;
+ count = be32_to_cpup(p);
+ if (count > NFS3_MAXNAMLEN)
+ goto out_nametoolong;
+ p = xdr_inline_decode(xdr, count);
+ if (unlikely(!p))
+ return -EIO;
+ *name = (const char *)p;
+ *length = count;
+ return 0;
+out_nametoolong:
+ dprintk("NFS: returned filename too long: %u\n", count);
+ return -ENAMETOOLONG;
+}
+
+/*
+ * 2.3.8. path
+ *
+ * typedef string path<MAXPATHLEN>;
+ */
+static void encode_path(struct xdr_stream *xdr, struct page **pages, u32 length)
+{
+ __be32 *p;
+
+ p = xdr_reserve_space(xdr, 4);
+ *p = cpu_to_be32(length);
+ xdr_write_pages(xdr, pages, 0, length);
+}
+
+static int decode_path(struct xdr_stream *xdr)
+{
+ u32 length, recvd;
+ __be32 *p;
+
+ p = xdr_inline_decode(xdr, 4);
+ if (unlikely(!p))
+ return -EIO;
+ length = be32_to_cpup(p);
+ if (unlikely(length >= xdr->buf->page_len || length > NFS_MAXPATHLEN))
+ goto out_size;
+ recvd = xdr_read_pages(xdr, length);
+ if (unlikely(length > recvd))
+ goto out_cheating;
+ xdr_terminate_string(xdr->buf, length);
+ return 0;
+out_size:
+ dprintk("NFS: returned pathname too long: %u\n", length);
+ return -ENAMETOOLONG;
+out_cheating:
+ dprintk("NFS: server cheating in pathname result: "
+ "length %u > received %u\n", length, recvd);
+ return -EIO;
+}
+
+/*
+ * 2.3.9. attrstat
+ *
+ * union attrstat switch (stat status) {
+ * case NFS_OK:
+ * fattr attributes;
+ * default:
+ * void;
+ * };
+ */
+static int decode_attrstat(struct xdr_stream *xdr, struct nfs_fattr *result,
+ __u32 *op_status,
+ struct user_namespace *userns)
+{
+ enum nfs_stat status;
+ int error;
+
+ error = decode_stat(xdr, &status);
+ if (unlikely(error))
+ goto out;
+ if (op_status)
+ *op_status = status;
+ if (status != NFS_OK)
+ goto out_default;
+ error = decode_fattr(xdr, result, userns);
+out:
+ return error;
+out_default:
+ return nfs_stat_to_errno(status);
+}
+
+/*
+ * 2.3.10. diropargs
+ *
+ * struct diropargs {
+ * fhandle dir;
+ * filename name;
+ * };
+ */
+static void encode_diropargs(struct xdr_stream *xdr, const struct nfs_fh *fh,
+ const char *name, u32 length)
+{
+ encode_fhandle(xdr, fh);
+ encode_filename(xdr, name, length);
+}
+
+/*
+ * 2.3.11. diropres
+ *
+ * union diropres switch (stat status) {
+ * case NFS_OK:
+ * struct {
+ * fhandle file;
+ * fattr attributes;
+ * } diropok;
+ * default:
+ * void;
+ * };
+ */
+static int decode_diropok(struct xdr_stream *xdr, struct nfs_diropok *result,
+ struct user_namespace *userns)
+{
+ int error;
+
+ error = decode_fhandle(xdr, result->fh);
+ if (unlikely(error))
+ goto out;
+ error = decode_fattr(xdr, result->fattr, userns);
+out:
+ return error;
+}
+
+static int decode_diropres(struct xdr_stream *xdr, struct nfs_diropok *result,
+ struct user_namespace *userns)
+{
+ enum nfs_stat status;
+ int error;
+
+ error = decode_stat(xdr, &status);
+ if (unlikely(error))
+ goto out;
+ if (status != NFS_OK)
+ goto out_default;
+ error = decode_diropok(xdr, result, userns);
+out:
+ return error;
+out_default:
+ return nfs_stat_to_errno(status);
+}
+
+
+/*
+ * NFSv2 XDR encode functions
+ *
+ * NFSv2 argument types are defined in section 2.2 of RFC 1094:
+ * "NFS: Network File System Protocol Specification".
+ */
+
+static void nfs2_xdr_enc_fhandle(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ const void *data)
+{
+ const struct nfs_fh *fh = data;
+
+ encode_fhandle(xdr, fh);
+}
+
+/*
+ * 2.2.3. sattrargs
+ *
+ * struct sattrargs {
+ * fhandle file;
+ * sattr attributes;
+ * };
+ */
+static void nfs2_xdr_enc_sattrargs(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ const void *data)
+{
+ const struct nfs_sattrargs *args = data;
+
+ encode_fhandle(xdr, args->fh);
+ encode_sattr(xdr, args->sattr, rpc_rqst_userns(req));
+}
+
+static void nfs2_xdr_enc_diropargs(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ const void *data)
+{
+ const struct nfs_diropargs *args = data;
+
+ encode_diropargs(xdr, args->fh, args->name, args->len);
+}
+
+static void nfs2_xdr_enc_readlinkargs(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ const void *data)
+{
+ const struct nfs_readlinkargs *args = data;
+
+ encode_fhandle(xdr, args->fh);
+ rpc_prepare_reply_pages(req, args->pages, args->pgbase, args->pglen,
+ NFS_readlinkres_sz - NFS_pagepad_sz);
+}
+
+/*
+ * 2.2.7. readargs
+ *
+ * struct readargs {
+ * fhandle file;
+ * unsigned offset;
+ * unsigned count;
+ * unsigned totalcount;
+ * };
+ */
+static void encode_readargs(struct xdr_stream *xdr,
+ const struct nfs_pgio_args *args)
+{
+ u32 offset = args->offset;
+ u32 count = args->count;
+ __be32 *p;
+
+ encode_fhandle(xdr, args->fh);
+
+ p = xdr_reserve_space(xdr, 4 + 4 + 4);
+ *p++ = cpu_to_be32(offset);
+ *p++ = cpu_to_be32(count);
+ *p = cpu_to_be32(count);
+}
+
+static void nfs2_xdr_enc_readargs(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ const void *data)
+{
+ const struct nfs_pgio_args *args = data;
+
+ encode_readargs(xdr, args);
+ rpc_prepare_reply_pages(req, args->pages, args->pgbase, args->count,
+ NFS_readres_sz - NFS_pagepad_sz);
+ req->rq_rcv_buf.flags |= XDRBUF_READ;
+}
+
+/*
+ * 2.2.9. writeargs
+ *
+ * struct writeargs {
+ * fhandle file;
+ * unsigned beginoffset;
+ * unsigned offset;
+ * unsigned totalcount;
+ * nfsdata data;
+ * };
+ */
+static void encode_writeargs(struct xdr_stream *xdr,
+ const struct nfs_pgio_args *args)
+{
+ u32 offset = args->offset;
+ u32 count = args->count;
+ __be32 *p;
+
+ encode_fhandle(xdr, args->fh);
+
+ p = xdr_reserve_space(xdr, 4 + 4 + 4 + 4);
+ *p++ = cpu_to_be32(offset);
+ *p++ = cpu_to_be32(offset);
+ *p++ = cpu_to_be32(count);
+
+ /* nfsdata */
+ *p = cpu_to_be32(count);
+ xdr_write_pages(xdr, args->pages, args->pgbase, count);
+}
+
+static void nfs2_xdr_enc_writeargs(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ const void *data)
+{
+ const struct nfs_pgio_args *args = data;
+
+ encode_writeargs(xdr, args);
+ xdr->buf->flags |= XDRBUF_WRITE;
+}
+
+/*
+ * 2.2.10. createargs
+ *
+ * struct createargs {
+ * diropargs where;
+ * sattr attributes;
+ * };
+ */
+static void nfs2_xdr_enc_createargs(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ const void *data)
+{
+ const struct nfs_createargs *args = data;
+
+ encode_diropargs(xdr, args->fh, args->name, args->len);
+ encode_sattr(xdr, args->sattr, rpc_rqst_userns(req));
+}
+
+static void nfs2_xdr_enc_removeargs(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ const void *data)
+{
+ const struct nfs_removeargs *args = data;
+
+ encode_diropargs(xdr, args->fh, args->name.name, args->name.len);
+}
+
+/*
+ * 2.2.12. renameargs
+ *
+ * struct renameargs {
+ * diropargs from;
+ * diropargs to;
+ * };
+ */
+static void nfs2_xdr_enc_renameargs(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ const void *data)
+{
+ const struct nfs_renameargs *args = data;
+ const struct qstr *old = args->old_name;
+ const struct qstr *new = args->new_name;
+
+ encode_diropargs(xdr, args->old_dir, old->name, old->len);
+ encode_diropargs(xdr, args->new_dir, new->name, new->len);
+}
+
+/*
+ * 2.2.13. linkargs
+ *
+ * struct linkargs {
+ * fhandle from;
+ * diropargs to;
+ * };
+ */
+static void nfs2_xdr_enc_linkargs(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ const void *data)
+{
+ const struct nfs_linkargs *args = data;
+
+ encode_fhandle(xdr, args->fromfh);
+ encode_diropargs(xdr, args->tofh, args->toname, args->tolen);
+}
+
+/*
+ * 2.2.14. symlinkargs
+ *
+ * struct symlinkargs {
+ * diropargs from;
+ * path to;
+ * sattr attributes;
+ * };
+ */
+static void nfs2_xdr_enc_symlinkargs(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ const void *data)
+{
+ const struct nfs_symlinkargs *args = data;
+
+ encode_diropargs(xdr, args->fromfh, args->fromname, args->fromlen);
+ encode_path(xdr, args->pages, args->pathlen);
+ encode_sattr(xdr, args->sattr, rpc_rqst_userns(req));
+}
+
+/*
+ * 2.2.17. readdirargs
+ *
+ * struct readdirargs {
+ * fhandle dir;
+ * nfscookie cookie;
+ * unsigned count;
+ * };
+ */
+static void encode_readdirargs(struct xdr_stream *xdr,
+ const struct nfs_readdirargs *args)
+{
+ __be32 *p;
+
+ encode_fhandle(xdr, args->fh);
+
+ p = xdr_reserve_space(xdr, 4 + 4);
+ *p++ = cpu_to_be32(args->cookie);
+ *p = cpu_to_be32(args->count);
+}
+
+static void nfs2_xdr_enc_readdirargs(struct rpc_rqst *req,
+ struct xdr_stream *xdr,
+ const void *data)
+{
+ const struct nfs_readdirargs *args = data;
+
+ encode_readdirargs(xdr, args);
+ rpc_prepare_reply_pages(req, args->pages, 0, args->count,
+ NFS_readdirres_sz - NFS_pagepad_sz);
+}
+
+/*
+ * NFSv2 XDR decode functions
+ *
+ * NFSv2 result types are defined in section 2.2 of RFC 1094:
+ * "NFS: Network File System Protocol Specification".
+ */
+
+static int nfs2_xdr_dec_stat(struct rpc_rqst *req, struct xdr_stream *xdr,
+ void *__unused)
+{
+ enum nfs_stat status;
+ int error;
+
+ error = decode_stat(xdr, &status);
+ if (unlikely(error))
+ goto out;
+ if (status != NFS_OK)
+ goto out_default;
+out:
+ return error;
+out_default:
+ return nfs_stat_to_errno(status);
+}
+
+static int nfs2_xdr_dec_attrstat(struct rpc_rqst *req, struct xdr_stream *xdr,
+ void *result)
+{
+ return decode_attrstat(xdr, result, NULL, rpc_rqst_userns(req));
+}
+
+static int nfs2_xdr_dec_diropres(struct rpc_rqst *req, struct xdr_stream *xdr,
+ void *result)
+{
+ return decode_diropres(xdr, result, rpc_rqst_userns(req));
+}
+
+/*
+ * 2.2.6. readlinkres
+ *
+ * union readlinkres switch (stat status) {
+ * case NFS_OK:
+ * path data;
+ * default:
+ * void;
+ * };
+ */
+static int nfs2_xdr_dec_readlinkres(struct rpc_rqst *req,
+ struct xdr_stream *xdr, void *__unused)
+{
+ enum nfs_stat status;
+ int error;
+
+ error = decode_stat(xdr, &status);
+ if (unlikely(error))
+ goto out;
+ if (status != NFS_OK)
+ goto out_default;
+ error = decode_path(xdr);
+out:
+ return error;
+out_default:
+ return nfs_stat_to_errno(status);
+}
+
+/*
+ * 2.2.7. readres
+ *
+ * union readres switch (stat status) {
+ * case NFS_OK:
+ * fattr attributes;
+ * nfsdata data;
+ * default:
+ * void;
+ * };
+ */
+static int nfs2_xdr_dec_readres(struct rpc_rqst *req, struct xdr_stream *xdr,
+ void *data)
+{
+ struct nfs_pgio_res *result = data;
+ enum nfs_stat status;
+ int error;
+
+ error = decode_stat(xdr, &status);
+ if (unlikely(error))
+ goto out;
+ result->op_status = status;
+ if (status != NFS_OK)
+ goto out_default;
+ error = decode_fattr(xdr, result->fattr, rpc_rqst_userns(req));
+ if (unlikely(error))
+ goto out;
+ error = decode_nfsdata(xdr, result);
+out:
+ return error;
+out_default:
+ return nfs_stat_to_errno(status);
+}
+
+static int nfs2_xdr_dec_writeres(struct rpc_rqst *req, struct xdr_stream *xdr,
+ void *data)
+{
+ struct nfs_pgio_res *result = data;
+
+ /* All NFSv2 writes are "file sync" writes */
+ result->verf->committed = NFS_FILE_SYNC;
+ return decode_attrstat(xdr, result->fattr, &result->op_status,
+ rpc_rqst_userns(req));
+}
+
+/**
+ * nfs2_decode_dirent - Decode a single NFSv2 directory entry stored in
+ * the local page cache.
+ * @xdr: XDR stream where entry resides
+ * @entry: buffer to fill in with entry data
+ * @plus: boolean indicating whether this should be a readdirplus entry
+ *
+ * Returns zero if successful, otherwise a negative errno value is
+ * returned.
+ *
+ * This function is not invoked during READDIR reply decoding, but
+ * rather whenever an application invokes the getdents(2) system call
+ * on a directory already in our cache.
+ *
+ * 2.2.17. entry
+ *
+ * struct entry {
+ * unsigned fileid;
+ * filename name;
+ * nfscookie cookie;
+ * entry *nextentry;
+ * };
+ */
+int nfs2_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry,
+ bool plus)
+{
+ __be32 *p;
+ int error;
+
+ p = xdr_inline_decode(xdr, 4);
+ if (unlikely(!p))
+ return -EAGAIN;
+ if (*p++ == xdr_zero) {
+ p = xdr_inline_decode(xdr, 4);
+ if (unlikely(!p))
+ return -EAGAIN;
+ if (*p++ == xdr_zero)
+ return -EAGAIN;
+ entry->eof = 1;
+ return -EBADCOOKIE;
+ }
+
+ p = xdr_inline_decode(xdr, 4);
+ if (unlikely(!p))
+ return -EAGAIN;
+ entry->ino = be32_to_cpup(p);
+
+ error = decode_filename_inline(xdr, &entry->name, &entry->len);
+ if (unlikely(error))
+ return error == -ENAMETOOLONG ? -ENAMETOOLONG : -EAGAIN;
+
+ /*
+ * The type (size and byte order) of nfscookie isn't defined in
+ * RFC 1094. This implementation assumes that it's an XDR uint32.
+ */
+ p = xdr_inline_decode(xdr, 4);
+ if (unlikely(!p))
+ return -EAGAIN;
+ entry->cookie = be32_to_cpup(p);
+
+ entry->d_type = DT_UNKNOWN;
+
+ return 0;
+}
+
+/*
+ * 2.2.17. readdirres
+ *
+ * union readdirres switch (stat status) {
+ * case NFS_OK:
+ * struct {
+ * entry *entries;
+ * bool eof;
+ * } readdirok;
+ * default:
+ * void;
+ * };
+ *
+ * Read the directory contents into the page cache, but don't
+ * touch them. The actual decoding is done by nfs2_decode_dirent()
+ * during subsequent nfs_readdir() calls.
+ */
+static int decode_readdirok(struct xdr_stream *xdr)
+{
+ return xdr_read_pages(xdr, xdr->buf->page_len);
+}
+
+static int nfs2_xdr_dec_readdirres(struct rpc_rqst *req,
+ struct xdr_stream *xdr, void *__unused)
+{
+ enum nfs_stat status;
+ int error;
+
+ error = decode_stat(xdr, &status);
+ if (unlikely(error))
+ goto out;
+ if (status != NFS_OK)
+ goto out_default;
+ error = decode_readdirok(xdr);
+out:
+ return error;
+out_default:
+ return nfs_stat_to_errno(status);
+}
+
+/*
+ * 2.2.18. statfsres
+ *
+ * union statfsres (stat status) {
+ * case NFS_OK:
+ * struct {
+ * unsigned tsize;
+ * unsigned bsize;
+ * unsigned blocks;
+ * unsigned bfree;
+ * unsigned bavail;
+ * } info;
+ * default:
+ * void;
+ * };
+ */
+static int decode_info(struct xdr_stream *xdr, struct nfs2_fsstat *result)
+{
+ __be32 *p;
+
+ p = xdr_inline_decode(xdr, NFS_info_sz << 2);
+ if (unlikely(!p))
+ return -EIO;
+ result->tsize = be32_to_cpup(p++);
+ result->bsize = be32_to_cpup(p++);
+ result->blocks = be32_to_cpup(p++);
+ result->bfree = be32_to_cpup(p++);
+ result->bavail = be32_to_cpup(p);
+ return 0;
+}
+
+static int nfs2_xdr_dec_statfsres(struct rpc_rqst *req, struct xdr_stream *xdr,
+ void *result)
+{
+ enum nfs_stat status;
+ int error;
+
+ error = decode_stat(xdr, &status);
+ if (unlikely(error))
+ goto out;
+ if (status != NFS_OK)
+ goto out_default;
+ error = decode_info(xdr, result);
+out:
+ return error;
+out_default:
+ return nfs_stat_to_errno(status);
+}
+
+
+/*
+ * We need to translate between nfs status return values and
+ * the local errno values which may not be the same.
+ */
+static const struct {
+ int stat;
+ int errno;
+} nfs_errtbl[] = {
+ { NFS_OK, 0 },
+ { NFSERR_PERM, -EPERM },
+ { NFSERR_NOENT, -ENOENT },
+ { NFSERR_IO, -errno_NFSERR_IO},
+ { NFSERR_NXIO, -ENXIO },
+/* { NFSERR_EAGAIN, -EAGAIN }, */
+ { NFSERR_ACCES, -EACCES },
+ { NFSERR_EXIST, -EEXIST },
+ { NFSERR_XDEV, -EXDEV },
+ { NFSERR_NODEV, -ENODEV },
+ { NFSERR_NOTDIR, -ENOTDIR },
+ { NFSERR_ISDIR, -EISDIR },
+ { NFSERR_INVAL, -EINVAL },
+ { NFSERR_FBIG, -EFBIG },
+ { NFSERR_NOSPC, -ENOSPC },
+ { NFSERR_ROFS, -EROFS },
+ { NFSERR_MLINK, -EMLINK },
+ { NFSERR_NAMETOOLONG, -ENAMETOOLONG },
+ { NFSERR_NOTEMPTY, -ENOTEMPTY },
+ { NFSERR_DQUOT, -EDQUOT },
+ { NFSERR_STALE, -ESTALE },
+ { NFSERR_REMOTE, -EREMOTE },
+#ifdef EWFLUSH
+ { NFSERR_WFLUSH, -EWFLUSH },
+#endif
+ { NFSERR_BADHANDLE, -EBADHANDLE },
+ { NFSERR_NOT_SYNC, -ENOTSYNC },
+ { NFSERR_BAD_COOKIE, -EBADCOOKIE },
+ { NFSERR_NOTSUPP, -ENOTSUPP },
+ { NFSERR_TOOSMALL, -ETOOSMALL },
+ { NFSERR_SERVERFAULT, -EREMOTEIO },
+ { NFSERR_BADTYPE, -EBADTYPE },
+ { NFSERR_JUKEBOX, -EJUKEBOX },
+ { -1, -EIO }
+};
+
+/**
+ * nfs_stat_to_errno - convert an NFS status code to a local errno
+ * @status: NFS status code to convert
+ *
+ * Returns a local errno value, or -EIO if the NFS status code is
+ * not recognized. This function is used jointly by NFSv2 and NFSv3.
+ */
+static int nfs_stat_to_errno(enum nfs_stat status)
+{
+ int i;
+
+ for (i = 0; nfs_errtbl[i].stat != -1; i++) {
+ if (nfs_errtbl[i].stat == (int)status)
+ return nfs_errtbl[i].errno;
+ }
+ dprintk("NFS: Unrecognized nfs status value: %u\n", status);
+ return nfs_errtbl[i].errno;
+}
+
+#define PROC(proc, argtype, restype, timer) \
+[NFSPROC_##proc] = { \
+ .p_proc = NFSPROC_##proc, \
+ .p_encode = nfs2_xdr_enc_##argtype, \
+ .p_decode = nfs2_xdr_dec_##restype, \
+ .p_arglen = NFS_##argtype##_sz, \
+ .p_replen = NFS_##restype##_sz, \
+ .p_timer = timer, \
+ .p_statidx = NFSPROC_##proc, \
+ .p_name = #proc, \
+ }
+const struct rpc_procinfo nfs_procedures[] = {
+ PROC(GETATTR, fhandle, attrstat, 1),
+ PROC(SETATTR, sattrargs, attrstat, 0),
+ PROC(LOOKUP, diropargs, diropres, 2),
+ PROC(READLINK, readlinkargs, readlinkres, 3),
+ PROC(READ, readargs, readres, 3),
+ PROC(WRITE, writeargs, writeres, 4),
+ PROC(CREATE, createargs, diropres, 0),
+ PROC(REMOVE, removeargs, stat, 0),
+ PROC(RENAME, renameargs, stat, 0),
+ PROC(LINK, linkargs, stat, 0),
+ PROC(SYMLINK, symlinkargs, stat, 0),
+ PROC(MKDIR, createargs, diropres, 0),
+ PROC(RMDIR, diropargs, stat, 0),
+ PROC(READDIR, readdirargs, readdirres, 3),
+ PROC(STATFS, fhandle, statfsres, 0),
+};
+
+static unsigned int nfs_version2_counts[ARRAY_SIZE(nfs_procedures)];
+const struct rpc_version nfs_version2 = {
+ .number = 2,
+ .nrprocs = ARRAY_SIZE(nfs_procedures),
+ .procs = nfs_procedures,
+ .counts = nfs_version2_counts,
+};