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linux/fs/nfs/nfs2xdr.c

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// 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 "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_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)
#define NFS_readres_sz (1+NFS_fattr_sz+1)
#define NFS_writeres_sz (NFS_attrstat_sz)
#define NFS_stat_sz (1)
#define NFS_readdirres_sz (1)
#define NFS_statfsres_sz (1+NFS_info_sz)
static int nfs_stat_to_errno(enum nfs_stat);
/*
* While encoding arguments, set up the reply buffer in advance to
* receive reply data directly into the page cache.
*/
static void prepare_reply_buffer(struct rpc_rqst *req, struct page **pages,
unsigned int base, unsigned int len,
unsigned int bufsize)
{
struct rpc_auth *auth = req->rq_cred->cr_auth;
unsigned int replen;
replen = RPC_REPHDRSIZE + auth->au_rslack + bufsize;
xdr_inline_pages(&req->rq_rcv_buf, replen << 2, pages, base, len);
}
/*
* Handle decode buffer overflows out-of-line.
*/
static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)
{
dprintk("NFS: %s prematurely hit the end of our receive buffer. "
"Remaining buffer length is %tu words.\n",
func, xdr->end - xdr->p);
}
/*
* 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.
*/
/*
* 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 == NULL))
goto out_overflow;
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;
out_overflow:
print_overflow_msg(__func__, xdr);
return -EIO;
}
/*
* 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 == NULL))
goto out_overflow;
*status = be32_to_cpup(p);
return 0;
out_overflow:
print_overflow_msg(__func__, xdr);
return -EIO;
}
/*
* 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 == NULL))
goto out_overflow;
fh->size = NFS2_FHSIZE;
memcpy(fh->data, p, NFS2_FHSIZE);
return 0;
out_overflow:
print_overflow_msg(__func__, xdr);
return -EIO;
}
/*
* 2.3.4. timeval
*
* struct timeval {
* unsigned int seconds;
* unsigned int useconds;
* };
*/
static __be32 *xdr_encode_time(__be32 *p, const struct timespec *timep)
{
*p++ = cpu_to_be32(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 timespec *timep)
{
*p++ = cpu_to_be32(timep->tv_sec);
*p++ = cpu_to_be32(1000000);
return p;
}
static __be32 *xdr_decode_time(__be32 *p, struct timespec *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)
{
u32 rdev, type;
__be32 *p;
p = xdr_inline_decode(xdr, NFS_fattr_sz << 2);
if (unlikely(p == NULL))
goto out_overflow;
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(&init_user_ns, be32_to_cpup(p++));
if (!uid_valid(fattr->uid))
goto out_uid;
fattr->gid = make_kgid(&init_user_ns, 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;
out_overflow:
print_overflow_msg(__func__, xdr);
return -EIO;
}
/*
* 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 timespec ts;
__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(&init_user_ns, attr->ia_uid));
else
*p++ = cpu_to_be32(NFS2_SATTR_NOT_SET);
if (attr->ia_valid & ATTR_GID)
*p++ = cpu_to_be32(from_kgid(&init_user_ns, 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) {
ts = timespec64_to_timespec(attr->ia_atime);
p = xdr_encode_time(p, &ts);
} else if (attr->ia_valid & ATTR_ATIME) {
ts = timespec64_to_timespec(attr->ia_atime);
p = xdr_encode_current_server_time(p, &ts);
} else
p = xdr_time_not_set(p);
if (attr->ia_valid & ATTR_MTIME_SET) {
ts = timespec64_to_timespec(attr->ia_atime);
xdr_encode_time(p, &ts);
} else if (attr->ia_valid & ATTR_MTIME) {
ts = timespec64_to_timespec(attr->ia_mtime);
xdr_encode_current_server_time(p, &ts);
} 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 == NULL))
goto out_overflow;
count = be32_to_cpup(p);
if (count > NFS3_MAXNAMLEN)
goto out_nametoolong;
p = xdr_inline_decode(xdr, count);
if (unlikely(p == NULL))
goto out_overflow;
*name = (const char *)p;
*length = count;
return 0;
out_nametoolong:
dprintk("NFS: returned filename too long: %u\n", count);
return -ENAMETOOLONG;
out_overflow:
print_overflow_msg(__func__, xdr);
return -EIO;
}
/*
* 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 == NULL))
goto out_overflow;
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;
out_overflow:
print_overflow_msg(__func__, xdr);
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)
{
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);
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)
{
int error;
error = decode_fhandle(xdr, result->fh);
if (unlikely(error))
goto out;
error = decode_fattr(xdr, result->fattr);
out:
return error;
}
static int decode_diropres(struct xdr_stream *xdr, struct nfs_diropok *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_diropok(xdr, result);
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);
}
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);
prepare_reply_buffer(req, args->pages, args->pgbase,
args->pglen, NFS_readlinkres_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);
prepare_reply_buffer(req, args->pages, args->pgbase,
args->count, NFS_readres_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);
}
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);
}
/*
* 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);
prepare_reply_buffer(req, args->pages, 0,
args->count, NFS_readdirres_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);
}
static int nfs2_xdr_dec_diropres(struct rpc_rqst *req, struct xdr_stream *xdr,
void *result)
{
return decode_diropres(xdr, result);
}
/*
* 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);
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);
}
/**
* 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 == NULL))
goto out_overflow;
if (*p++ == xdr_zero) {
p = xdr_inline_decode(xdr, 4);
if (unlikely(p == NULL))
goto out_overflow;
if (*p++ == xdr_zero)
return -EAGAIN;
entry->eof = 1;
return -EBADCOOKIE;
}
p = xdr_inline_decode(xdr, 4);
if (unlikely(p == NULL))
goto out_overflow;
entry->ino = be32_to_cpup(p);
error = decode_filename_inline(xdr, &entry->name, &entry->len);
if (unlikely(error))
return error;
/*
* The type (size and byte order) of nfscookie isn't defined in
* RFC 1094. This implementation assumes that it's an XDR uint32.
*/
entry->prev_cookie = entry->cookie;
p = xdr_inline_decode(xdr, 4);
if (unlikely(p == NULL))
goto out_overflow;
entry->cookie = be32_to_cpup(p);
entry->d_type = DT_UNKNOWN;
return 0;
out_overflow:
print_overflow_msg(__func__, xdr);
return -EAGAIN;
}
/*
* 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 == NULL))
goto out_overflow;
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;
out_overflow:
print_overflow_msg(__func__, xdr);
return -EIO;
}
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,
};
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