NFS: Reset nfsi->last_updated only if the attribute changed

Otherwise set it to nfsi->read_cache_jiffies in order to prevent jiffy
wraparound issues.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 1c23d3a..9d012a6 100644 (file)
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -956,7 +956,6 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
         * Update the read time so we don't revalidate too often.
         */
        nfsi->read_cache_jiffies = fattr->time_start;
-       nfsi->last_updated = now;
 
        nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR | NFS_INO_INVALID_ATIME
                        | NFS_INO_REVAL_PAGECACHE);
@@ -1027,10 +1026,18 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
                nfs_inc_stats(inode, NFSIOS_ATTRINVALIDATE);
                nfsi->attrtimeo = NFS_MINATTRTIMEO(inode);
                nfsi->attrtimeo_timestamp = now;
-       } else if (!time_in_range(now, nfsi->attrtimeo_timestamp, nfsi->attrtimeo_timestamp + nfsi->attrtimeo)) {
-               if ((nfsi->attrtimeo <<= 1) > NFS_MAXATTRTIMEO(inode))
-                       nfsi->attrtimeo = NFS_MAXATTRTIMEO(inode);
-               nfsi->attrtimeo_timestamp = now;
+               nfsi->last_updated = now;
+       } else {
+               if (!time_in_range(now, nfsi->attrtimeo_timestamp, nfsi->attrtimeo_timestamp + nfsi->attrtimeo)) {
+                       if ((nfsi->attrtimeo <<= 1) > NFS_MAXATTRTIMEO(inode))
+                               nfsi->attrtimeo = NFS_MAXATTRTIMEO(inode);
+                       nfsi->attrtimeo_timestamp = now;
+               }
+               /*
+                * Avoid jiffy wraparound issues with nfsi->last_updated
+                */
+               if (!time_in_range(nfsi->last_updated, nfsi->read_cache_jiffies, now))
+                       nfsi->last_updated = nfsi->read_cache_jiffies;
        }
        invalid &= ~NFS_INO_INVALID_ATTR;
        /* Don't invalidate the data if we were to blame */