Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / fs / nfsd / nfs3xdr.c
diff --git a/kernel/fs/nfsd/nfs3xdr.c b/kernel/fs/nfsd/nfs3xdr.c
new file mode 100644 (file)
index 0000000..e4b2b43
--- /dev/null
@@ -0,0 +1,1114 @@
+/*
+ * 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 timespec *time)
+{
+       *p++ = htonl((u32) time->tv_sec); *p++ = htonl(time->tv_nsec);
+       return p;
+}
+
+static __be32 *
+decode_time3(__be32 *p, struct timespec *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)
+{
+       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(&init_user_ns, ntohl(*p++));
+               if (uid_valid(iap->ia_uid))
+                       iap->ia_valid |= ATTR_UID;
+       }
+       if (*p++) {
+               iap->ia_gid = make_kgid(&init_user_ns, 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
+                                    (d_inode(fhp->fh_dentry)->i_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)
+{
+       *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(&init_user_ns, stat->uid));
+       *p++ = htonl((u32) from_kgid(&init_user_ns, 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 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 = d_inode(fhp->fh_dentry)->i_version;
+       if (err) {
+               fhp->fh_post_saved = 0;
+               /* 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 = 1;
+}
+
+/*
+ * XDR decode functions
+ */
+int
+nfs3svc_decode_fhandle(struct svc_rqst *rqstp, __be32 *p, struct nfsd_fhandle *args)
+{
+       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)
+{
+       p = decode_fh(p, &args->fh);
+       if (!p)
+               return 0;
+       p = decode_sattr3(p, &args->attrs);
+
+       if ((args->check_guard = ntohl(*p++)) != 0) { 
+               struct timespec 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)
+{
+       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)
+{
+       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)
+{
+       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)
+{
+       unsigned int len, v, hdr, dlen;
+       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++);
+       args->stable = ntohl(*p++);
+       len = args->len = ntohl(*p++);
+       /*
+        * 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 - rqstp->rq_arg.head[0].iov_base;
+       dlen = rqstp->rq_arg.head[0].iov_len + rqstp->rq_arg.page_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;
+       }
+       rqstp->rq_vec[0].iov_base = (void*)p;
+       rqstp->rq_vec[0].iov_len = rqstp->rq_arg.head[0].iov_len - hdr;
+       v = 0;
+       while (len > rqstp->rq_vec[v].iov_len) {
+               len -= rqstp->rq_vec[v].iov_len;
+               v++;
+               rqstp->rq_vec[v].iov_base = page_address(rqstp->rq_pages[v]);
+               rqstp->rq_vec[v].iov_len = PAGE_SIZE;
+       }
+       rqstp->rq_vec[v].iov_len = len;
+       args->vlen = v + 1;
+       return 1;
+}
+
+int
+nfs3svc_decode_createargs(struct svc_rqst *rqstp, __be32 *p,
+                                       struct nfsd3_createargs *args)
+{
+       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);
+               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)
+{
+       if (!(p = decode_fh(p, &args->fh)) ||
+           !(p = decode_filename(p, &args->name, &args->len)))
+               return 0;
+       p = decode_sattr3(p, &args->attrs);
+
+       return xdr_argsize_check(rqstp, p);
+}
+
+int
+nfs3svc_decode_symlinkargs(struct svc_rqst *rqstp, __be32 *p,
+                                       struct nfsd3_symlinkargs *args)
+{
+       unsigned int len, avail;
+       char *old, *new;
+       struct kvec *vec;
+
+       if (!(p = decode_fh(p, &args->ffh)) ||
+           !(p = decode_filename(p, &args->fname, &args->flen))
+               )
+               return 0;
+       p = decode_sattr3(p, &args->attrs);
+
+       /* now decode the pathname, which might be larger than the first page.
+        * As we have to check for nul's anyway, we copy it into a new page
+        * This page appears in the rq_res.pages list, but as pages_len is always
+        * 0, it won't get in the way
+        */
+       len = ntohl(*p++);
+       if (len == 0 || len > NFS3_MAXPATHLEN || len >= PAGE_SIZE)
+               return 0;
+       args->tname = new = page_address(*(rqstp->rq_next_page++));
+       args->tlen = len;
+       /* first copy and check from the first page */
+       old = (char*)p;
+       vec = &rqstp->rq_arg.head[0];
+       avail = vec->iov_len - (old - (char*)vec->iov_base);
+       while (len && avail && *old) {
+               *new++ = *old++;
+               len--;
+               avail--;
+       }
+       /* now copy next page if there is one */
+       if (len && !avail && rqstp->rq_arg.page_len) {
+               avail = min_t(unsigned int, rqstp->rq_arg.page_len, PAGE_SIZE);
+               old = page_address(rqstp->rq_arg.pages[0]);
+       }
+       while (len && avail && *old) {
+               *new++ = *old++;
+               len--;
+               avail--;
+       }
+       *new = '\0';
+       if (len)
+               return 0;
+
+       return 1;
+}
+
+int
+nfs3svc_decode_mknodargs(struct svc_rqst *rqstp, __be32 *p,
+                                       struct nfsd3_mknodargs *args)
+{
+       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);
+
+       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)
+{
+       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)
+{
+       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)
+{
+       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)
+{
+       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++);
+       args->count  = min_t(u32, args->count, PAGE_SIZE);
+       args->buffer = page_address(*(rqstp->rq_next_page++));
+
+       return xdr_argsize_check(rqstp, p);
+}
+
+int
+nfs3svc_decode_readdirplusargs(struct svc_rqst *rqstp, __be32 *p,
+                                       struct nfsd3_readdirargs *args)
+{
+       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)
+{
+       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, void *dummy)
+{
+       return xdr_ressize_check(rqstp, p);
+}
+
+/* GETATTR */
+int
+nfs3svc_encode_attrstat(struct svc_rqst *rqstp, __be32 *p,
+                                       struct nfsd3_attrstat *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)
+{
+       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)
+{
+       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)
+{
+       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)
+{
+       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)
+{
+       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)
+{
+       struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
+
+       p = encode_wcc_data(rqstp, p, &resp->fh);
+       if (resp->status == 0) {
+               *p++ = htonl(resp->count);
+               *p++ = htonl(resp->committed);
+               *p++ = htonl(nn->nfssvc_boot.tv_sec);
+               *p++ = htonl(nn->nfssvc_boot.tv_usec);
+       }
+       return xdr_ressize_check(rqstp, p);
+}
+
+/* CREATE, MKDIR, SYMLINK, MKNOD */
+int
+nfs3svc_encode_createres(struct svc_rqst *rqstp, __be32 *p,
+                                       struct nfsd3_diropres *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)
+{
+       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)
+{
+       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)
+{
+       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)
+{
+       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_one_len(name, dparent, namlen);
+       if (IS_ERR(dchild))
+               return rv;
+       if (d_mountpoint(dchild))
+               goto out;
+       if (d_really_is_negative(dchild))
+               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)
+{
+       struct svc_fh   *fh = &cd->scratch;
+       __be32 err;
+
+       fh_init(fh, NFS3_FHSIZE);
+       err = compose_entry_fh(cd, fh, name, namlen);
+       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);
+               }
+       }
+
+       /*
+       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);
+               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);
+
+               /* 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)
+{
+       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)
+{
+       *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)
+{
+       *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)
+{
+       struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
+
+       p = encode_wcc_data(rqstp, p, &resp->fh);
+       /* Write verifier */
+       if (resp->status == 0) {
+               *p++ = htonl(nn->nfssvc_boot.tv_sec);
+               *p++ = htonl(nn->nfssvc_boot.tv_usec);
+       }
+       return xdr_ressize_check(rqstp, p);
+}
+
+/*
+ * XDR release functions
+ */
+int
+nfs3svc_release_fhandle(struct svc_rqst *rqstp, __be32 *p,
+                                       struct nfsd3_attrstat *resp)
+{
+       fh_put(&resp->fh);
+       return 1;
+}
+
+int
+nfs3svc_release_fhandle2(struct svc_rqst *rqstp, __be32 *p,
+                                       struct nfsd3_fhandle_pair *resp)
+{
+       fh_put(&resp->fh1);
+       fh_put(&resp->fh2);
+       return 1;
+}