From 3ecb34ecc2f3e0e0f4912d7eebd97f732e4cfebb Mon Sep 17 00:00:00 2001
From: "J. Bruce Fields" <bfields@redhat.com>
Date: Fri, 29 Jan 2021 14:27:01 -0500
Subject: [PATCH] nfsd: skip some unnecessary stats in the v4 case
[ Upstream commit 428a23d2bf0ca8fd4d364a464c3e468f0e81671e ]
In the typical case of v4 and an i_version-supporting filesystem, we can
skip a stat which is only required to fake up a change attribute from
ctime.
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/nfsd/nfs3xdr.c | 44 +++++++++++++++++++++++++++-----------------
1 file changed, 27 insertions(+), 17 deletions(-)
diff --git a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c
index 00a960542..9d9a01ce0 100755
--- a/fs/nfsd/nfs3xdr.c
+++ b/fs/nfsd/nfs3xdr.c
@@ -364,6 +364,11 @@ encode_wcc_data(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp)
return encode_post_op_attr(rqstp, p, fhp);
}
+static bool fs_supports_change_attribute(struct super_block *sb)
+{
+ return sb->s_flags & SB_I_VERSION || sb->s_export_op->fetch_iversion;
+}
+
/*
* Fill in the pre_op attr for the wcc data
*/
@@ -372,24 +377,26 @@ void fill_pre_wcc(struct svc_fh *fhp)
struct inode *inode;
struct kstat stat;
bool v4 = (fhp->fh_maxsize == NFS4_FHSIZE);
- __be32 err;
if (fhp->fh_no_wcc || fhp->fh_pre_saved)
return;
inode = d_inode(fhp->fh_dentry);
- err = fh_getattr(fhp, &stat);
- if (err) {
- /* Grab the times from inode anyway */
- stat.mtime = inode->i_mtime;
- stat.ctime = inode->i_ctime;
- stat.size = inode->i_size;
+ if (fs_supports_change_attribute(inode->i_sb) || !v4) {
+ __be32 err = fh_getattr(fhp, &stat);
+
+ if (err) {
+ /* Grab the times from inode anyway */
+ stat.mtime = inode->i_mtime;
+ stat.ctime = inode->i_ctime;
+ stat.size = inode->i_size;
+ }
+ fhp->fh_pre_mtime = stat.mtime;
+ fhp->fh_pre_ctime = stat.ctime;
+ fhp->fh_pre_size = stat.size;
}
if (v4)
fhp->fh_pre_change = nfsd4_change_attribute(&stat, inode);
- fhp->fh_pre_mtime = stat.mtime;
- fhp->fh_pre_ctime = stat.ctime;
- fhp->fh_pre_size = stat.size;
fhp->fh_pre_saved = true;
}
@@ -400,7 +407,6 @@ void fill_post_wcc(struct svc_fh *fhp)
{
bool v4 = (fhp->fh_maxsize == NFS4_FHSIZE);
struct inode *inode = d_inode(fhp->fh_dentry);
- __be32 err;
if (fhp->fh_no_wcc)
return;
@@ -408,12 +414,16 @@ void fill_post_wcc(struct svc_fh *fhp)
if (fhp->fh_post_saved)
printk("nfsd: inode locked twice during operation.\n");
- err = fh_getattr(fhp, &fhp->fh_post_attr);
- if (err) {
- fhp->fh_post_saved = false;
- fhp->fh_post_attr.ctime = inode->i_ctime;
- } else
- fhp->fh_post_saved = true;
+ fhp->fh_post_saved = true;
+
+ if (fs_supports_change_attribute(inode->i_sb) || !v4) {
+ __be32 err = fh_getattr(fhp, &fhp->fh_post_attr);
+
+ if (err) {
+ fhp->fh_post_saved = false;
+ fhp->fh_post_attr.ctime = inode->i_ctime;
+ }
+ }
if (v4)
fhp->fh_post_change =
nfsd4_change_attribute(&fhp->fh_post_attr, inode);