From: NeilBrown <neilb@cse.unsw.edu.au>
The "offset" in an entry in an nfs3 readdir response is 64 bits long and as it
has only a 32 bit alignment, it fall half in one page of the response and half
in another.
This patch adds a second offset pointer (offset1) which points to the second
half in the unusual case of the offset being split between pages, and sets and
uses it accordingly.
From: Olaf Kirch <okir@suse.de>
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
---
25-akpm/fs/nfsd/nfs3proc.c | 1
25-akpm/fs/nfsd/nfs3xdr.c | 39 +++++++++++++++++++++++++++++++-------
25-akpm/include/linux/nfsd/xdr3.h | 1
3 files changed, 33 insertions(+), 8 deletions(-)
diff -puN fs/nfsd/nfs3proc.c~knfsd-1-of-11-fix-nfs3-dentry-encoding fs/nfsd/nfs3proc.c
--- 25/fs/nfsd/nfs3proc.c~knfsd-1-of-11-fix-nfs3-dentry-encoding 2004-05-28 00:07:57.078434328 -0700
+++ 25-akpm/fs/nfsd/nfs3proc.c 2004-05-28 00:07:57.085433264 -0700
@@ -436,7 +436,6 @@ nfsd3_proc_readdir(struct svc_rqst *rqst
resp->buflen = count;
resp->common.err = nfs_ok;
resp->buffer = argp->buffer;
- resp->offset = NULL;
resp->rqstp = rqstp;
nfserr = nfsd_readdir(rqstp, &resp->fh, (loff_t*) &argp->cookie,
&resp->common, nfs3svc_encode_entry);
diff -puN fs/nfsd/nfs3xdr.c~knfsd-1-of-11-fix-nfs3-dentry-encoding fs/nfsd/nfs3xdr.c
--- 25/fs/nfsd/nfs3xdr.c~knfsd-1-of-11-fix-nfs3-dentry-encoding 2004-05-28 00:07:57.080434024 -0700
+++ 25-akpm/fs/nfsd/nfs3xdr.c 2004-05-28 00:07:57.086433112 -0700
@@ -847,8 +847,18 @@ encode_entry(struct readdir_cd *ccd, con
int elen; /* estimated entry length in words */
int num_entry_words = 0; /* actual number of words */
- if (cd->offset)
- xdr_encode_hyper(cd->offset, (u64) offset);
+ 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, (u64) offset);
+ }
+ }
/*
dprintk("encode_entry(%.*s @%ld%s)\n",
@@ -929,17 +939,32 @@ encode_entry(struct readdir_cd *ccd, con
/* 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);
- /* update offset */
- if (((cd->offset - tmp) << 2) < len1)
- cd->offset = p + (cd->offset - tmp);
- else
- cd->offset -= len1 >> 2;
p = tmp + (len2 >> 2);
}
}
diff -puN include/linux/nfsd/xdr3.h~knfsd-1-of-11-fix-nfs3-dentry-encoding include/linux/nfsd/xdr3.h
--- 25/include/linux/nfsd/xdr3.h~knfsd-1-of-11-fix-nfs3-dentry-encoding 2004-05-28 00:07:57.081433872 -0700
+++ 25-akpm/include/linux/nfsd/xdr3.h 2004-05-28 00:07:57.087432960 -0700
@@ -170,6 +170,7 @@ struct nfsd3_readdirres {
u32 * buffer;
int buflen;
u32 * offset;
+ u32 * offset1;
struct svc_rqst * rqstp;
};
_