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>

1 files changed, 12 insertions, 5 deletions

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 1c23d3a67c85..9d012a6ee4cc 100644
--- 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 */