linux/fs/nfsd/nfs3xdr.c
Trond Myklebust 19e0663ff9 nfsd: Ensure sampling of the write verifier is atomic with the write
When doing an unstable write, we need to ensure that we sample the
write verifier before releasing the lock, and allowing a commit to
the same file to proceed.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2020-01-22 16:25:41 -05:00

1149 lines
27 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* XDR support for nfsd/protocol version 3.
*
* Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
*
* 2003-08-09 Jamie Lokier: Use htonl() for nanoseconds, not htons()!
*/
#include <linux/namei.h>
#include <linux/sunrpc/svc_xprt.h>
#include "xdr3.h"
#include "auth.h"
#include "netns.h"
#include "vfs.h"
#define NFSDDBG_FACILITY NFSDDBG_XDR
/*
* Mapping of S_IF* types to NFS file types
*/
static u32 nfs3_ftypes[] = {
NF3NON, NF3FIFO, NF3CHR, NF3BAD,
NF3DIR, NF3BAD, NF3BLK, NF3BAD,
NF3REG, NF3BAD, NF3LNK, NF3BAD,
NF3SOCK, NF3BAD, NF3LNK, NF3BAD,
};
/*
* XDR functions for basic NFS types
*/
static __be32 *
encode_time3(__be32 *p, struct timespec64 *time)
{
*p++ = htonl((u32) time->tv_sec); *p++ = htonl(time->tv_nsec);
return p;
}
static __be32 *
decode_time3(__be32 *p, struct timespec64 *time)
{
time->tv_sec = ntohl(*p++);
time->tv_nsec = ntohl(*p++);
return p;
}
static __be32 *
decode_fh(__be32 *p, struct svc_fh *fhp)
{
unsigned int size;
fh_init(fhp, NFS3_FHSIZE);
size = ntohl(*p++);
if (size > NFS3_FHSIZE)
return NULL;
memcpy(&fhp->fh_handle.fh_base, p, size);
fhp->fh_handle.fh_size = size;
return p + XDR_QUADLEN(size);
}
/* Helper function for NFSv3 ACL code */
__be32 *nfs3svc_decode_fh(__be32 *p, struct svc_fh *fhp)
{
return decode_fh(p, fhp);
}
static __be32 *
encode_fh(__be32 *p, struct svc_fh *fhp)
{
unsigned int size = fhp->fh_handle.fh_size;
*p++ = htonl(size);
if (size) p[XDR_QUADLEN(size)-1]=0;
memcpy(p, &fhp->fh_handle.fh_base, size);
return p + XDR_QUADLEN(size);
}
/*
* Decode a file name and make sure that the path contains
* no slashes or null bytes.
*/
static __be32 *
decode_filename(__be32 *p, char **namp, unsigned int *lenp)
{
char *name;
unsigned int i;
if ((p = xdr_decode_string_inplace(p, namp, lenp, NFS3_MAXNAMLEN)) != NULL) {
for (i = 0, name = *namp; i < *lenp; i++, name++) {
if (*name == '\0' || *name == '/')
return NULL;
}
}
return p;
}
static __be32 *
decode_sattr3(__be32 *p, struct iattr *iap, struct user_namespace *userns)
{
u32 tmp;
iap->ia_valid = 0;
if (*p++) {
iap->ia_valid |= ATTR_MODE;
iap->ia_mode = ntohl(*p++);
}
if (*p++) {
iap->ia_uid = make_kuid(userns, ntohl(*p++));
if (uid_valid(iap->ia_uid))
iap->ia_valid |= ATTR_UID;
}
if (*p++) {
iap->ia_gid = make_kgid(userns, ntohl(*p++));
if (gid_valid(iap->ia_gid))
iap->ia_valid |= ATTR_GID;
}
if (*p++) {
u64 newsize;
iap->ia_valid |= ATTR_SIZE;
p = xdr_decode_hyper(p, &newsize);
iap->ia_size = min_t(u64, newsize, NFS_OFFSET_MAX);
}
if ((tmp = ntohl(*p++)) == 1) { /* set to server time */
iap->ia_valid |= ATTR_ATIME;
} else if (tmp == 2) { /* set to client time */
iap->ia_valid |= ATTR_ATIME | ATTR_ATIME_SET;
iap->ia_atime.tv_sec = ntohl(*p++);
iap->ia_atime.tv_nsec = ntohl(*p++);
}
if ((tmp = ntohl(*p++)) == 1) { /* set to server time */
iap->ia_valid |= ATTR_MTIME;
} else if (tmp == 2) { /* set to client time */
iap->ia_valid |= ATTR_MTIME | ATTR_MTIME_SET;
iap->ia_mtime.tv_sec = ntohl(*p++);
iap->ia_mtime.tv_nsec = ntohl(*p++);
}
return p;
}
static __be32 *encode_fsid(__be32 *p, struct svc_fh *fhp)
{
u64 f;
switch(fsid_source(fhp)) {
default:
case FSIDSOURCE_DEV:
p = xdr_encode_hyper(p, (u64)huge_encode_dev
(fhp->fh_dentry->d_sb->s_dev));
break;
case FSIDSOURCE_FSID:
p = xdr_encode_hyper(p, (u64) fhp->fh_export->ex_fsid);
break;
case FSIDSOURCE_UUID:
f = ((u64*)fhp->fh_export->ex_uuid)[0];
f ^= ((u64*)fhp->fh_export->ex_uuid)[1];
p = xdr_encode_hyper(p, f);
break;
}
return p;
}
static __be32 *
encode_fattr3(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp,
struct kstat *stat)
{
struct user_namespace *userns = nfsd_user_namespace(rqstp);
*p++ = htonl(nfs3_ftypes[(stat->mode & S_IFMT) >> 12]);
*p++ = htonl((u32) (stat->mode & S_IALLUGO));
*p++ = htonl((u32) stat->nlink);
*p++ = htonl((u32) from_kuid_munged(userns, stat->uid));
*p++ = htonl((u32) from_kgid_munged(userns, stat->gid));
if (S_ISLNK(stat->mode) && stat->size > NFS3_MAXPATHLEN) {
p = xdr_encode_hyper(p, (u64) NFS3_MAXPATHLEN);
} else {
p = xdr_encode_hyper(p, (u64) stat->size);
}
p = xdr_encode_hyper(p, ((u64)stat->blocks) << 9);
*p++ = htonl((u32) MAJOR(stat->rdev));
*p++ = htonl((u32) MINOR(stat->rdev));
p = encode_fsid(p, fhp);
p = xdr_encode_hyper(p, stat->ino);
p = encode_time3(p, &stat->atime);
p = encode_time3(p, &stat->mtime);
p = encode_time3(p, &stat->ctime);
return p;
}
static __be32 *
encode_saved_post_attr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
{
/* Attributes to follow */
*p++ = xdr_one;
return encode_fattr3(rqstp, p, fhp, &fhp->fh_post_attr);
}
/*
* Encode post-operation attributes.
* The inode may be NULL if the call failed because of a stale file
* handle. In this case, no attributes are returned.
*/
static __be32 *
encode_post_op_attr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
{
struct dentry *dentry = fhp->fh_dentry;
if (dentry && d_really_is_positive(dentry)) {
__be32 err;
struct kstat stat;
err = fh_getattr(fhp, &stat);
if (!err) {
*p++ = xdr_one; /* attributes follow */
lease_get_mtime(d_inode(dentry), &stat.mtime);
return encode_fattr3(rqstp, p, fhp, &stat);
}
}
*p++ = xdr_zero;
return p;
}
/* Helper for NFSv3 ACLs */
__be32 *
nfs3svc_encode_post_op_attr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
{
return encode_post_op_attr(rqstp, p, fhp);
}
/*
* Enocde weak cache consistency data
*/
static __be32 *
encode_wcc_data(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
{
struct dentry *dentry = fhp->fh_dentry;
if (dentry && d_really_is_positive(dentry) && fhp->fh_post_saved) {
if (fhp->fh_pre_saved) {
*p++ = xdr_one;
p = xdr_encode_hyper(p, (u64) fhp->fh_pre_size);
p = encode_time3(p, &fhp->fh_pre_mtime);
p = encode_time3(p, &fhp->fh_pre_ctime);
} else {
*p++ = xdr_zero;
}
return encode_saved_post_attr(rqstp, p, fhp);
}
/* no pre- or post-attrs */
*p++ = xdr_zero;
return encode_post_op_attr(rqstp, p, fhp);
}
/*
* Fill in the pre_op attr for the wcc data
*/
void fill_pre_wcc(struct svc_fh *fhp)
{
struct inode *inode;
struct kstat stat;
__be32 err;
if (fhp->fh_pre_saved)
return;
inode = d_inode(fhp->fh_dentry);
err = fh_getattr(fhp, &stat);
if (err) {
/* Grab the times from inode anyway */
stat.mtime = inode->i_mtime;
stat.ctime = inode->i_ctime;
stat.size = inode->i_size;
}
fhp->fh_pre_mtime = stat.mtime;
fhp->fh_pre_ctime = stat.ctime;
fhp->fh_pre_size = stat.size;
fhp->fh_pre_change = nfsd4_change_attribute(&stat, inode);
fhp->fh_pre_saved = true;
}
/*
* Fill in the post_op attr for the wcc data
*/
void fill_post_wcc(struct svc_fh *fhp)
{
__be32 err;
if (fhp->fh_post_saved)
printk("nfsd: inode locked twice during operation.\n");
err = fh_getattr(fhp, &fhp->fh_post_attr);
fhp->fh_post_change = nfsd4_change_attribute(&fhp->fh_post_attr,
d_inode(fhp->fh_dentry));
if (err) {
fhp->fh_post_saved = false;
/* Grab the ctime anyway - set_change_info might use it */
fhp->fh_post_attr.ctime = d_inode(fhp->fh_dentry)->i_ctime;
} else
fhp->fh_post_saved = true;
}
/*
* XDR decode functions
*/
int
nfs3svc_decode_fhandle(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd_fhandle *args = rqstp->rq_argp;
p = decode_fh(p, &args->fh);
if (!p)
return 0;
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_sattrargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_sattrargs *args = rqstp->rq_argp;
p = decode_fh(p, &args->fh);
if (!p)
return 0;
p = decode_sattr3(p, &args->attrs, nfsd_user_namespace(rqstp));
if ((args->check_guard = ntohl(*p++)) != 0) {
struct timespec64 time;
p = decode_time3(p, &time);
args->guardtime = time.tv_sec;
}
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_diropargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_diropargs *args = rqstp->rq_argp;
if (!(p = decode_fh(p, &args->fh))
|| !(p = decode_filename(p, &args->name, &args->len)))
return 0;
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_accessargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_accessargs *args = rqstp->rq_argp;
p = decode_fh(p, &args->fh);
if (!p)
return 0;
args->access = ntohl(*p++);
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_readargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_readargs *args = rqstp->rq_argp;
unsigned int len;
int v;
u32 max_blocksize = svc_max_payload(rqstp);
p = decode_fh(p, &args->fh);
if (!p)
return 0;
p = xdr_decode_hyper(p, &args->offset);
args->count = ntohl(*p++);
len = min(args->count, max_blocksize);
/* set up the kvec */
v=0;
while (len > 0) {
struct page *p = *(rqstp->rq_next_page++);
rqstp->rq_vec[v].iov_base = page_address(p);
rqstp->rq_vec[v].iov_len = min_t(unsigned int, len, PAGE_SIZE);
len -= rqstp->rq_vec[v].iov_len;
v++;
}
args->vlen = v;
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_writeargs *args = rqstp->rq_argp;
unsigned int len, hdr, dlen;
u32 max_blocksize = svc_max_payload(rqstp);
struct kvec *head = rqstp->rq_arg.head;
struct kvec *tail = rqstp->rq_arg.tail;
p = decode_fh(p, &args->fh);
if (!p)
return 0;
p = xdr_decode_hyper(p, &args->offset);
args->count = ntohl(*p++);
args->stable = ntohl(*p++);
len = args->len = ntohl(*p++);
if ((void *)p > head->iov_base + head->iov_len)
return 0;
/*
* The count must equal the amount of data passed.
*/
if (args->count != args->len)
return 0;
/*
* Check to make sure that we got the right number of
* bytes.
*/
hdr = (void*)p - head->iov_base;
dlen = head->iov_len + rqstp->rq_arg.page_len + tail->iov_len - hdr;
/*
* Round the length of the data which was specified up to
* the next multiple of XDR units and then compare that
* against the length which was actually received.
* Note that when RPCSEC/GSS (for example) is used, the
* data buffer can be padded so dlen might be larger
* than required. It must never be smaller.
*/
if (dlen < XDR_QUADLEN(len)*4)
return 0;
if (args->count > max_blocksize) {
args->count = max_blocksize;
len = args->len = max_blocksize;
}
args->first.iov_base = (void *)p;
args->first.iov_len = head->iov_len - hdr;
return 1;
}
int
nfs3svc_decode_createargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_createargs *args = rqstp->rq_argp;
if (!(p = decode_fh(p, &args->fh))
|| !(p = decode_filename(p, &args->name, &args->len)))
return 0;
switch (args->createmode = ntohl(*p++)) {
case NFS3_CREATE_UNCHECKED:
case NFS3_CREATE_GUARDED:
p = decode_sattr3(p, &args->attrs, nfsd_user_namespace(rqstp));
break;
case NFS3_CREATE_EXCLUSIVE:
args->verf = p;
p += 2;
break;
default:
return 0;
}
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_mkdirargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_createargs *args = rqstp->rq_argp;
if (!(p = decode_fh(p, &args->fh)) ||
!(p = decode_filename(p, &args->name, &args->len)))
return 0;
p = decode_sattr3(p, &args->attrs, nfsd_user_namespace(rqstp));
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_symlinkargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_symlinkargs *args = rqstp->rq_argp;
char *base = (char *)p;
size_t dlen;
if (!(p = decode_fh(p, &args->ffh)) ||
!(p = decode_filename(p, &args->fname, &args->flen)))
return 0;
p = decode_sattr3(p, &args->attrs, nfsd_user_namespace(rqstp));
args->tlen = ntohl(*p++);
args->first.iov_base = p;
args->first.iov_len = rqstp->rq_arg.head[0].iov_len;
args->first.iov_len -= (char *)p - base;
dlen = args->first.iov_len + rqstp->rq_arg.page_len +
rqstp->rq_arg.tail[0].iov_len;
if (dlen < XDR_QUADLEN(args->tlen) << 2)
return 0;
return 1;
}
int
nfs3svc_decode_mknodargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_mknodargs *args = rqstp->rq_argp;
if (!(p = decode_fh(p, &args->fh))
|| !(p = decode_filename(p, &args->name, &args->len)))
return 0;
args->ftype = ntohl(*p++);
if (args->ftype == NF3BLK || args->ftype == NF3CHR
|| args->ftype == NF3SOCK || args->ftype == NF3FIFO)
p = decode_sattr3(p, &args->attrs, nfsd_user_namespace(rqstp));
if (args->ftype == NF3BLK || args->ftype == NF3CHR) {
args->major = ntohl(*p++);
args->minor = ntohl(*p++);
}
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_renameargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_renameargs *args = rqstp->rq_argp;
if (!(p = decode_fh(p, &args->ffh))
|| !(p = decode_filename(p, &args->fname, &args->flen))
|| !(p = decode_fh(p, &args->tfh))
|| !(p = decode_filename(p, &args->tname, &args->tlen)))
return 0;
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_readlinkargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_readlinkargs *args = rqstp->rq_argp;
p = decode_fh(p, &args->fh);
if (!p)
return 0;
args->buffer = page_address(*(rqstp->rq_next_page++));
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_linkargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_linkargs *args = rqstp->rq_argp;
if (!(p = decode_fh(p, &args->ffh))
|| !(p = decode_fh(p, &args->tfh))
|| !(p = decode_filename(p, &args->tname, &args->tlen)))
return 0;
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_readdirargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_readdirargs *args = rqstp->rq_argp;
int len;
u32 max_blocksize = svc_max_payload(rqstp);
p = decode_fh(p, &args->fh);
if (!p)
return 0;
p = xdr_decode_hyper(p, &args->cookie);
args->verf = p; p += 2;
args->dircount = ~0;
args->count = ntohl(*p++);
len = args->count = min_t(u32, args->count, max_blocksize);
while (len > 0) {
struct page *p = *(rqstp->rq_next_page++);
if (!args->buffer)
args->buffer = page_address(p);
len -= PAGE_SIZE;
}
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_readdirplusargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_readdirargs *args = rqstp->rq_argp;
int len;
u32 max_blocksize = svc_max_payload(rqstp);
p = decode_fh(p, &args->fh);
if (!p)
return 0;
p = xdr_decode_hyper(p, &args->cookie);
args->verf = p; p += 2;
args->dircount = ntohl(*p++);
args->count = ntohl(*p++);
len = args->count = min(args->count, max_blocksize);
while (len > 0) {
struct page *p = *(rqstp->rq_next_page++);
if (!args->buffer)
args->buffer = page_address(p);
len -= PAGE_SIZE;
}
return xdr_argsize_check(rqstp, p);
}
int
nfs3svc_decode_commitargs(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_commitargs *args = rqstp->rq_argp;
p = decode_fh(p, &args->fh);
if (!p)
return 0;
p = xdr_decode_hyper(p, &args->offset);
args->count = ntohl(*p++);
return xdr_argsize_check(rqstp, p);
}
/*
* XDR encode functions
*/
/*
* There must be an encoding function for void results so svc_process
* will work properly.
*/
int
nfs3svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p)
{
return xdr_ressize_check(rqstp, p);
}
/* GETATTR */
int
nfs3svc_encode_attrstat(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_attrstat *resp = rqstp->rq_resp;
if (resp->status == 0) {
lease_get_mtime(d_inode(resp->fh.fh_dentry),
&resp->stat.mtime);
p = encode_fattr3(rqstp, p, &resp->fh, &resp->stat);
}
return xdr_ressize_check(rqstp, p);
}
/* SETATTR, REMOVE, RMDIR */
int
nfs3svc_encode_wccstat(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_attrstat *resp = rqstp->rq_resp;
p = encode_wcc_data(rqstp, p, &resp->fh);
return xdr_ressize_check(rqstp, p);
}
/* LOOKUP */
int
nfs3svc_encode_diropres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_diropres *resp = rqstp->rq_resp;
if (resp->status == 0) {
p = encode_fh(p, &resp->fh);
p = encode_post_op_attr(rqstp, p, &resp->fh);
}
p = encode_post_op_attr(rqstp, p, &resp->dirfh);
return xdr_ressize_check(rqstp, p);
}
/* ACCESS */
int
nfs3svc_encode_accessres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_accessres *resp = rqstp->rq_resp;
p = encode_post_op_attr(rqstp, p, &resp->fh);
if (resp->status == 0)
*p++ = htonl(resp->access);
return xdr_ressize_check(rqstp, p);
}
/* READLINK */
int
nfs3svc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_readlinkres *resp = rqstp->rq_resp;
p = encode_post_op_attr(rqstp, p, &resp->fh);
if (resp->status == 0) {
*p++ = htonl(resp->len);
xdr_ressize_check(rqstp, p);
rqstp->rq_res.page_len = resp->len;
if (resp->len & 3) {
/* need to pad the tail */
rqstp->rq_res.tail[0].iov_base = p;
*p = 0;
rqstp->rq_res.tail[0].iov_len = 4 - (resp->len&3);
}
return 1;
} else
return xdr_ressize_check(rqstp, p);
}
/* READ */
int
nfs3svc_encode_readres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_readres *resp = rqstp->rq_resp;
p = encode_post_op_attr(rqstp, p, &resp->fh);
if (resp->status == 0) {
*p++ = htonl(resp->count);
*p++ = htonl(resp->eof);
*p++ = htonl(resp->count); /* xdr opaque count */
xdr_ressize_check(rqstp, p);
/* now update rqstp->rq_res to reflect data as well */
rqstp->rq_res.page_len = resp->count;
if (resp->count & 3) {
/* need to pad the tail */
rqstp->rq_res.tail[0].iov_base = p;
*p = 0;
rqstp->rq_res.tail[0].iov_len = 4 - (resp->count & 3);
}
return 1;
} else
return xdr_ressize_check(rqstp, p);
}
/* WRITE */
int
nfs3svc_encode_writeres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_writeres *resp = rqstp->rq_resp;
p = encode_wcc_data(rqstp, p, &resp->fh);
if (resp->status == 0) {
*p++ = htonl(resp->count);
*p++ = htonl(resp->committed);
*p++ = resp->verf[0];
*p++ = resp->verf[1];
}
return xdr_ressize_check(rqstp, p);
}
/* CREATE, MKDIR, SYMLINK, MKNOD */
int
nfs3svc_encode_createres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_diropres *resp = rqstp->rq_resp;
if (resp->status == 0) {
*p++ = xdr_one;
p = encode_fh(p, &resp->fh);
p = encode_post_op_attr(rqstp, p, &resp->fh);
}
p = encode_wcc_data(rqstp, p, &resp->dirfh);
return xdr_ressize_check(rqstp, p);
}
/* RENAME */
int
nfs3svc_encode_renameres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_renameres *resp = rqstp->rq_resp;
p = encode_wcc_data(rqstp, p, &resp->ffh);
p = encode_wcc_data(rqstp, p, &resp->tfh);
return xdr_ressize_check(rqstp, p);
}
/* LINK */
int
nfs3svc_encode_linkres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_linkres *resp = rqstp->rq_resp;
p = encode_post_op_attr(rqstp, p, &resp->fh);
p = encode_wcc_data(rqstp, p, &resp->tfh);
return xdr_ressize_check(rqstp, p);
}
/* READDIR */
int
nfs3svc_encode_readdirres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_readdirres *resp = rqstp->rq_resp;
p = encode_post_op_attr(rqstp, p, &resp->fh);
if (resp->status == 0) {
/* stupid readdir cookie */
memcpy(p, resp->verf, 8); p += 2;
xdr_ressize_check(rqstp, p);
if (rqstp->rq_res.head[0].iov_len + (2<<2) > PAGE_SIZE)
return 1; /*No room for trailer */
rqstp->rq_res.page_len = (resp->count) << 2;
/* add the 'tail' to the end of the 'head' page - page 0. */
rqstp->rq_res.tail[0].iov_base = p;
*p++ = 0; /* no more entries */
*p++ = htonl(resp->common.err == nfserr_eof);
rqstp->rq_res.tail[0].iov_len = 2<<2;
return 1;
} else
return xdr_ressize_check(rqstp, p);
}
static __be32 *
encode_entry_baggage(struct nfsd3_readdirres *cd, __be32 *p, const char *name,
int namlen, u64 ino)
{
*p++ = xdr_one; /* mark entry present */
p = xdr_encode_hyper(p, ino); /* file id */
p = xdr_encode_array(p, name, namlen);/* name length & name */
cd->offset = p; /* remember pointer */
p = xdr_encode_hyper(p, NFS_OFFSET_MAX);/* offset of next entry */
return p;
}
static __be32
compose_entry_fh(struct nfsd3_readdirres *cd, struct svc_fh *fhp,
const char *name, int namlen, u64 ino)
{
struct svc_export *exp;
struct dentry *dparent, *dchild;
__be32 rv = nfserr_noent;
dparent = cd->fh.fh_dentry;
exp = cd->fh.fh_export;
if (isdotent(name, namlen)) {
if (namlen == 2) {
dchild = dget_parent(dparent);
/* filesystem root - cannot return filehandle for ".." */
if (dchild == dparent)
goto out;
} else
dchild = dget(dparent);
} else
dchild = lookup_positive_unlocked(name, dparent, namlen);
if (IS_ERR(dchild))
return rv;
if (d_mountpoint(dchild))
goto out;
if (dchild->d_inode->i_ino != ino)
goto out;
rv = fh_compose(fhp, exp, dchild, &cd->fh);
out:
dput(dchild);
return rv;
}
static __be32 *encode_entryplus_baggage(struct nfsd3_readdirres *cd, __be32 *p, const char *name, int namlen, u64 ino)
{
struct svc_fh *fh = &cd->scratch;
__be32 err;
fh_init(fh, NFS3_FHSIZE);
err = compose_entry_fh(cd, fh, name, namlen, ino);
if (err) {
*p++ = 0;
*p++ = 0;
goto out;
}
p = encode_post_op_attr(cd->rqstp, p, fh);
*p++ = xdr_one; /* yes, a file handle follows */
p = encode_fh(p, fh);
out:
fh_put(fh);
return p;
}
/*
* Encode a directory entry. This one works for both normal readdir
* and readdirplus.
* The normal readdir reply requires 2 (fileid) + 1 (stringlen)
* + string + 2 (cookie) + 1 (next) words, i.e. 6 + strlen.
*
* The readdirplus baggage is 1+21 words for post_op_attr, plus the
* file handle.
*/
#define NFS3_ENTRY_BAGGAGE (2 + 1 + 2 + 1)
#define NFS3_ENTRYPLUS_BAGGAGE (1 + 21 + 1 + (NFS3_FHSIZE >> 2))
static int
encode_entry(struct readdir_cd *ccd, const char *name, int namlen,
loff_t offset, u64 ino, unsigned int d_type, int plus)
{
struct nfsd3_readdirres *cd = container_of(ccd, struct nfsd3_readdirres,
common);
__be32 *p = cd->buffer;
caddr_t curr_page_addr = NULL;
struct page ** page;
int slen; /* string (name) length */
int elen; /* estimated entry length in words */
int num_entry_words = 0; /* actual number of words */
if (cd->offset) {
u64 offset64 = offset;
if (unlikely(cd->offset1)) {
/* we ended up with offset on a page boundary */
*cd->offset = htonl(offset64 >> 32);
*cd->offset1 = htonl(offset64 & 0xffffffff);
cd->offset1 = NULL;
} else {
xdr_encode_hyper(cd->offset, offset64);
}
cd->offset = NULL;
}
/*
dprintk("encode_entry(%.*s @%ld%s)\n",
namlen, name, (long) offset, plus? " plus" : "");
*/
/* truncate filename if too long */
namlen = min(namlen, NFS3_MAXNAMLEN);
slen = XDR_QUADLEN(namlen);
elen = slen + NFS3_ENTRY_BAGGAGE
+ (plus? NFS3_ENTRYPLUS_BAGGAGE : 0);
if (cd->buflen < elen) {
cd->common.err = nfserr_toosmall;
return -EINVAL;
}
/* determine which page in rq_respages[] we are currently filling */
for (page = cd->rqstp->rq_respages + 1;
page < cd->rqstp->rq_next_page; page++) {
curr_page_addr = page_address(*page);
if (((caddr_t)cd->buffer >= curr_page_addr) &&
((caddr_t)cd->buffer < curr_page_addr + PAGE_SIZE))
break;
}
if ((caddr_t)(cd->buffer + elen) < (curr_page_addr + PAGE_SIZE)) {
/* encode entry in current page */
p = encode_entry_baggage(cd, p, name, namlen, ino);
if (plus)
p = encode_entryplus_baggage(cd, p, name, namlen, ino);
num_entry_words = p - cd->buffer;
} else if (*(page+1) != NULL) {
/* temporarily encode entry into next page, then move back to
* current and next page in rq_respages[] */
__be32 *p1, *tmp;
int len1, len2;
/* grab next page for temporary storage of entry */
p1 = tmp = page_address(*(page+1));
p1 = encode_entry_baggage(cd, p1, name, namlen, ino);
if (plus)
p1 = encode_entryplus_baggage(cd, p1, name, namlen, ino);
/* determine entry word length and lengths to go in pages */
num_entry_words = p1 - tmp;
len1 = curr_page_addr + PAGE_SIZE - (caddr_t)cd->buffer;
if ((num_entry_words << 2) < len1) {
/* the actual number of words in the entry is less
* than elen and can still fit in the current page
*/
memmove(p, tmp, num_entry_words << 2);
p += num_entry_words;
/* update offset */
cd->offset = cd->buffer + (cd->offset - tmp);
} else {
unsigned int offset_r = (cd->offset - tmp) << 2;
/* update pointer to offset location.
* This is a 64bit quantity, so we need to
* deal with 3 cases:
* - entirely in first page
* - entirely in second page
* - 4 bytes in each page
*/
if (offset_r + 8 <= len1) {
cd->offset = p + (cd->offset - tmp);
} else if (offset_r >= len1) {
cd->offset -= len1 >> 2;
} else {
/* sitting on the fence */
BUG_ON(offset_r != len1 - 4);
cd->offset = p + (cd->offset - tmp);
cd->offset1 = tmp;
}
len2 = (num_entry_words << 2) - len1;
/* move from temp page to current and next pages */
memmove(p, tmp, len1);
memmove(tmp, (caddr_t)tmp+len1, len2);
p = tmp + (len2 >> 2);
}
}
else {
cd->common.err = nfserr_toosmall;
return -EINVAL;
}
cd->buflen -= num_entry_words;
cd->buffer = p;
cd->common.err = nfs_ok;
return 0;
}
int
nfs3svc_encode_entry(void *cd, const char *name,
int namlen, loff_t offset, u64 ino, unsigned int d_type)
{
return encode_entry(cd, name, namlen, offset, ino, d_type, 0);
}
int
nfs3svc_encode_entry_plus(void *cd, const char *name,
int namlen, loff_t offset, u64 ino,
unsigned int d_type)
{
return encode_entry(cd, name, namlen, offset, ino, d_type, 1);
}
/* FSSTAT */
int
nfs3svc_encode_fsstatres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_fsstatres *resp = rqstp->rq_resp;
struct kstatfs *s = &resp->stats;
u64 bs = s->f_bsize;
*p++ = xdr_zero; /* no post_op_attr */
if (resp->status == 0) {
p = xdr_encode_hyper(p, bs * s->f_blocks); /* total bytes */
p = xdr_encode_hyper(p, bs * s->f_bfree); /* free bytes */
p = xdr_encode_hyper(p, bs * s->f_bavail); /* user available bytes */
p = xdr_encode_hyper(p, s->f_files); /* total inodes */
p = xdr_encode_hyper(p, s->f_ffree); /* free inodes */
p = xdr_encode_hyper(p, s->f_ffree); /* user available inodes */
*p++ = htonl(resp->invarsec); /* mean unchanged time */
}
return xdr_ressize_check(rqstp, p);
}
/* FSINFO */
int
nfs3svc_encode_fsinfores(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_fsinfores *resp = rqstp->rq_resp;
*p++ = xdr_zero; /* no post_op_attr */
if (resp->status == 0) {
*p++ = htonl(resp->f_rtmax);
*p++ = htonl(resp->f_rtpref);
*p++ = htonl(resp->f_rtmult);
*p++ = htonl(resp->f_wtmax);
*p++ = htonl(resp->f_wtpref);
*p++ = htonl(resp->f_wtmult);
*p++ = htonl(resp->f_dtpref);
p = xdr_encode_hyper(p, resp->f_maxfilesize);
*p++ = xdr_one;
*p++ = xdr_zero;
*p++ = htonl(resp->f_properties);
}
return xdr_ressize_check(rqstp, p);
}
/* PATHCONF */
int
nfs3svc_encode_pathconfres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_pathconfres *resp = rqstp->rq_resp;
*p++ = xdr_zero; /* no post_op_attr */
if (resp->status == 0) {
*p++ = htonl(resp->p_link_max);
*p++ = htonl(resp->p_name_max);
*p++ = htonl(resp->p_no_trunc);
*p++ = htonl(resp->p_chown_restricted);
*p++ = htonl(resp->p_case_insensitive);
*p++ = htonl(resp->p_case_preserving);
}
return xdr_ressize_check(rqstp, p);
}
/* COMMIT */
int
nfs3svc_encode_commitres(struct svc_rqst *rqstp, __be32 *p)
{
struct nfsd3_commitres *resp = rqstp->rq_resp;
p = encode_wcc_data(rqstp, p, &resp->fh);
/* Write verifier */
if (resp->status == 0) {
*p++ = resp->verf[0];
*p++ = resp->verf[1];
}
return xdr_ressize_check(rqstp, p);
}
/*
* XDR release functions
*/
void
nfs3svc_release_fhandle(struct svc_rqst *rqstp)
{
struct nfsd3_attrstat *resp = rqstp->rq_resp;
fh_put(&resp->fh);
}
void
nfs3svc_release_fhandle2(struct svc_rqst *rqstp)
{
struct nfsd3_fhandle_pair *resp = rqstp->rq_resp;
fh_put(&resp->fh1);
fh_put(&resp->fh2);
}