This is a note to let you know that I've just added the patch titled
NFSD: Count bytes instead of pages in the NFSv2 READDIR encoder
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
nfsd-count-bytes-instead-of-pages-in-the-nfsv2-readd.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 206a632e7cd061b83292c406c3c2d4e2ac38f5ea
Author: Chuck Lever <chuck.lever@xxxxxxxxxx>
Date: Fri Nov 13 16:57:44 2020 -0500
NFSD: Count bytes instead of pages in the NFSv2 READDIR encoder
[ Upstream commit 8141d6a2bb6c655ff0c0b81ced80d9025f03e926 ]
Clean up: Counting the bytes used by each returned directory entry
seems less brittle to me than trying to measure consumed pages after
the fact.
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c
index 2d3d7cdffd52f..23b2a900cb79d 100644
--- a/fs/nfsd/nfsproc.c
+++ b/fs/nfsd/nfsproc.c
@@ -578,14 +578,12 @@ nfsd_proc_readdir(struct svc_rqst *rqstp)
struct nfsd_readdirargs *argp = rqstp->rq_argp;
struct nfsd_readdirres *resp = rqstp->rq_resp;
loff_t offset;
- __be32 *buffer;
dprintk("nfsd: READDIR %s %d bytes at %d\n",
SVCFH_fmt(&argp->fh),
argp->count, argp->cookie);
nfsd_init_dirlist_pages(rqstp, resp, argp->count);
- buffer = resp->buffer;
resp->offset = NULL;
resp->common.err = nfs_ok;
@@ -593,8 +591,6 @@ nfsd_proc_readdir(struct svc_rqst *rqstp)
offset = argp->cookie;
resp->status = nfsd_readdir(rqstp, &argp->fh, &offset,
&resp->common, nfssvc_encode_entry);
-
- resp->count = resp->buffer - buffer;
nfssvc_encode_nfscookie(resp, offset);
fh_put(&argp->fh);
diff --git a/fs/nfsd/nfsxdr.c b/fs/nfsd/nfsxdr.c
index a87b21cfe0d03..8ae23ed6dc5db 100644
--- a/fs/nfsd/nfsxdr.c
+++ b/fs/nfsd/nfsxdr.c
@@ -584,7 +584,7 @@ nfssvc_encode_readdirres(struct svc_rqst *rqstp, __be32 *p)
p = resp->buffer;
*p++ = 0; /* no more entries */
*p++ = htonl((resp->common.err == nfserr_eof));
- rqstp->rq_res.page_len = (((unsigned long)p-1) & ~PAGE_MASK)+1;
+ rqstp->rq_res.page_len = resp->count << 2;
return 1;
}
@@ -667,6 +667,7 @@ nfssvc_encode_entry(void *ccdv, const char *name,
cd->offset = p; /* remember pointer */
*p++ = htonl(~0U); /* offset of next entry */
+ cd->count += p - cd->buffer;
cd->buflen = buflen;
cd->buffer = p;
cd->common.err = nfs_ok;
