From: Trond Myklebust <trond.myklebust@hammerspace.com>
Date: Fri, 25 Jun 2021 19:49:31 +0000 (-0400)
Subject: NFSv4: Fix handling of non-atomic change attrbute updates
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=20cf7d4ea4ad7d9830b01ff7444f6ac64a727a23;p=linux.git

NFSv4: Fix handling of non-atomic change attrbute updates

If the change attribute update is declared to be non-atomic by the
server, or our cached value does not match the server's value before the
operation was performed, then we should declare the inode cache invalid.

On the other hand, if the change to the directory raced with a lookup or
getattr which already updated the change attribute, then optimise away
the revalidation.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index e653654c10bcd..451d3d56d80c7 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1205,12 +1205,12 @@ nfs4_update_changeattr_locked(struct inode *inode,
 	u64 change_attr = inode_peek_iversion_raw(inode);
 
 	cache_validity |= NFS_INO_INVALID_CTIME | NFS_INO_INVALID_MTIME;
+	if (S_ISDIR(inode->i_mode))
+		cache_validity |= NFS_INO_INVALID_DATA;
 
 	switch (NFS_SERVER(inode)->change_attr_type) {
 	case NFS4_CHANGE_TYPE_IS_UNDEFINED:
-		break;
-	case NFS4_CHANGE_TYPE_IS_TIME_METADATA:
-		if ((s64)(change_attr - cinfo->after) > 0)
+		if (cinfo->after == change_attr)
 			goto out;
 		break;
 	default:
@@ -1218,24 +1218,21 @@ nfs4_update_changeattr_locked(struct inode *inode,
 			goto out;
 	}
 
-	if (cinfo->atomic && cinfo->before == change_attr) {
-		nfsi->attrtimeo_timestamp = jiffies;
-	} else {
-		if (S_ISDIR(inode->i_mode)) {
-			cache_validity |= NFS_INO_INVALID_DATA;
+	inode_set_iversion_raw(inode, cinfo->after);
+	if (!cinfo->atomic || cinfo->before != change_attr) {
+		if (S_ISDIR(inode->i_mode))
 			nfs_force_lookup_revalidate(inode);
-		} else {
-			if (!NFS_PROTO(inode)->have_delegation(inode,
-							       FMODE_READ))
-				cache_validity |= NFS_INO_REVAL_PAGECACHE;
-		}
 
-		if (cinfo->before != change_attr)
-			cache_validity |= NFS_INO_INVALID_ACCESS |
-					  NFS_INO_INVALID_ACL |
-					  NFS_INO_INVALID_XATTR;
+		if (!NFS_PROTO(inode)->have_delegation(inode, FMODE_READ))
+			cache_validity |=
+				NFS_INO_INVALID_ACCESS | NFS_INO_INVALID_ACL |
+				NFS_INO_INVALID_SIZE | NFS_INO_INVALID_OTHER |
+				NFS_INO_INVALID_BLOCKS | NFS_INO_INVALID_NLINK |
+				NFS_INO_INVALID_MODE | NFS_INO_INVALID_XATTR |
+				NFS_INO_REVAL_PAGECACHE;
+		nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
 	}
-	inode_set_iversion_raw(inode, cinfo->after);
+	nfsi->attrtimeo_timestamp = jiffies;
 	nfsi->read_cache_jiffies = timestamp;
 	nfsi->attr_gencount = nfs_inc_attr_generation_counter();
 	nfsi->cache_validity &= ~NFS_INO_INVALID_CHANGE;