5.15-stable review patch. If anyone has any objections, please let me know.
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From: Chuck Lever chuck.lever@oracle.com
[ Upstream commit ab04de60ae1cc64ae16b77feae795311b97720c7 ]
write_bytes_to_xdr_buf() is a generic way to place a variable-length data item in an already-reserved spot in the encoding buffer.
However, it is costly. In nfsd4_encode_fattr(), it is unnecessary because the data item is fixed in size and the buffer destination address is always word-aligned.
Reviewed-by: Jeff Layton jlayton@kernel.org Signed-off-by: Chuck Lever chuck.lever@oracle.com --- fs/nfsd/nfs4xdr.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-)
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c index 9eba9afe13794..d5a4aa0da32be 100644 --- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -2825,10 +2825,9 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp, struct kstat stat; struct svc_fh *tempfh = NULL; struct kstatfs statfs; - __be32 *p; + __be32 *p, *attrlen_p; int starting_len = xdr->buf->len; int attrlen_offset; - __be32 attrlen; u32 dummy; u64 dummy64; u32 rdattr_err = 0; @@ -2916,10 +2915,9 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp, goto out;
attrlen_offset = xdr->buf->len; - p = xdr_reserve_space(xdr, 4); - if (!p) + attrlen_p = xdr_reserve_space(xdr, XDR_UNIT); + if (!attrlen_p) goto out_resource; - p++; /* to be backfilled later */
if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) { u32 supp[3]; @@ -3341,8 +3339,7 @@ nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp, *p++ = cpu_to_be32(err == 0); }
- attrlen = htonl(xdr->buf->len - attrlen_offset - 4); - write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4); + *attrlen_p = cpu_to_be32(xdr->buf->len - attrlen_offset - XDR_UNIT); status = nfs_ok;
out: