[PATCH v3 11/11] NFSD: Remove NFSSVC_MAXBLKSIZE from .pc_xdrressize

[cel@kernel.org]

From: Chuck Lever <chuck.lever@oracle.com>

The value in the .pc_xdrressize field is used to "reserve space in
the output queue". Relevant only to UDP transports, AFAICT.

The fixed value of NFSSVC_MAXBLKSIZE is added to that field for
NFSv2 and NFSv3 read requests, even though nfsd_proc_read() is
already careful to reserve the actual size of the read payload.
Adding the maximum payload size to .pc_xdrressize seems to be
unnecessary.

Also, instead of adding a constant 4 bytes for each payload's
XDR pad, add the actual size of the pad for better accuracy of
the reservation size.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---
 fs/nfsd/nfs3proc.c | 4 ++--
 fs/nfsd/nfsproc.c  | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c
index 372bdcf5e07a..dbb750a7b5db 100644
--- a/fs/nfsd/nfs3proc.c
+++ b/fs/nfsd/nfs3proc.c
@@ -202,7 +202,7 @@ nfsd3_proc_read(struct svc_rqst *rqstp)
 	 */
 	resp->count = argp->count;
 	svc_reserve_auth(rqstp, ((1 + NFS3_POST_OP_ATTR_WORDS + 3) << 2) +
-			 resp->count + 4);
+			 xdr_align_size(resp->count));
 
 	fh_copy(&resp->fh, &argp->fh);
 	resp->status = nfsd_read(rqstp, &resp->fh, argp->offset,
@@ -921,7 +921,7 @@ static const struct svc_procedure nfsd_procedures3[22] = {
 		.pc_argzero = sizeof(struct nfsd3_readargs),
 		.pc_ressize = sizeof(struct nfsd3_readres),
 		.pc_cachetype = RC_NOCACHE,
-		.pc_xdrressize = ST+pAT+4+NFSSVC_MAXBLKSIZE/4,
+		.pc_xdrressize = ST+pAT+3,
 		.pc_name = "READ",
 	},
 	[NFS3PROC_WRITE] = {
diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c
index 6dda081eb24c..a95faf726e58 100644
--- a/fs/nfsd/nfsproc.c
+++ b/fs/nfsd/nfsproc.c
@@ -219,7 +219,7 @@ nfsd_proc_read(struct svc_rqst *rqstp)
 	/* Obtain buffer pointer for payload. 19 is 1 word for
 	 * status, 17 words for fattr, and 1 word for the byte count.
 	 */
-	svc_reserve_auth(rqstp, (19<<2) + argp->count + 4);
+	svc_reserve_auth(rqstp, (19<<2) + xdr_align_size(argp->count));
 
 	resp->count = argp->count;
 	fh_copy(&resp->fh, &argp->fh);
@@ -739,7 +739,7 @@ static const struct svc_procedure nfsd_procedures2[18] = {
 		.pc_argzero = sizeof(struct nfsd_readargs),
 		.pc_ressize = sizeof(struct nfsd_readres),
 		.pc_cachetype = RC_NOCACHE,
-		.pc_xdrressize = ST+AT+1+NFSSVC_MAXBLKSIZE_V2/4,
+		.pc_xdrressize = ST+AT+1,
 		.pc_name = "READ",
 	},
 	[NFSPROC_WRITECACHE] = {
-- 
2.49.0