NFS: Further fixes to attribute delegation a/mtime changes

When asked to set both an atime and an mtime to the current system time,
ensure that the setting is atomic by calling inode_update_timestamps()
only once with the appropriate flags.

Fixes: e12912d94137 ("NFSv4: Add support for delegated atime and mtime attributes")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 1e71b029da584821fef27067013bac6bc7a58b37..9e884e1ce5d8ef5180ec81680da3cd36830faf29 100644 (file)
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -628,23 +628,35 @@ nfs_fattr_fixup_delegated(struct inode *inode, struct nfs_fattr *fattr)
        }
 }
 
+static void nfs_update_timestamps(struct inode *inode, unsigned int ia_valid)
+{
+       enum file_time_flags time_flags = 0;
+       unsigned int cache_flags = 0;
+
+       if (ia_valid & ATTR_MTIME) {
+               time_flags |= S_MTIME | S_CTIME;
+               cache_flags |= NFS_INO_INVALID_CTIME | NFS_INO_INVALID_MTIME;
+       }
+       if (ia_valid & ATTR_ATIME) {
+               time_flags |= S_ATIME;
+               cache_flags |= NFS_INO_INVALID_ATIME;
+       }
+       inode_update_timestamps(inode, time_flags);
+       NFS_I(inode)->cache_validity &= ~cache_flags;
+}
+
 void nfs_update_delegated_atime(struct inode *inode)
 {
        spin_lock(&inode->i_lock);
-       if (nfs_have_delegated_atime(inode)) {
-               inode_update_timestamps(inode, S_ATIME);
-               NFS_I(inode)->cache_validity &= ~NFS_INO_INVALID_ATIME;
-       }
+       if (nfs_have_delegated_atime(inode))
+               nfs_update_timestamps(inode, ATTR_ATIME);
        spin_unlock(&inode->i_lock);
 }
 
 void nfs_update_delegated_mtime_locked(struct inode *inode)
 {
-       if (nfs_have_delegated_mtime(inode)) {
-               inode_update_timestamps(inode, S_CTIME | S_MTIME);
-               NFS_I(inode)->cache_validity &= ~(NFS_INO_INVALID_CTIME |
-                                                 NFS_INO_INVALID_MTIME);
-       }
+       if (nfs_have_delegated_mtime(inode))
+               nfs_update_timestamps(inode, ATTR_MTIME);
 }
 
 void nfs_update_delegated_mtime(struct inode *inode)
@@ -682,15 +694,16 @@ nfs_setattr(struct mnt_idmap *idmap, struct dentry *dentry,
                        attr->ia_valid &= ~ATTR_SIZE;
        }
 
-       if (nfs_have_delegated_mtime(inode)) {
-               if (attr->ia_valid & ATTR_MTIME) {
-                       nfs_update_delegated_mtime(inode);
-                       attr->ia_valid &= ~ATTR_MTIME;
-               }
-               if (attr->ia_valid & ATTR_ATIME) {
-                       nfs_update_delegated_atime(inode);
-                       attr->ia_valid &= ~ATTR_ATIME;
-               }
+       if (nfs_have_delegated_mtime(inode) && attr->ia_valid & ATTR_MTIME) {
+               spin_lock(&inode->i_lock);
+               nfs_update_timestamps(inode, attr->ia_valid);
+               spin_unlock(&inode->i_lock);
+               attr->ia_valid &= ~(ATTR_MTIME | ATTR_ATIME);
+       } else if (nfs_have_delegated_atime(inode) &&
+                  attr->ia_valid & ATTR_ATIME &&
+                  !(attr->ia_valid & ATTR_MTIME)) {
+               nfs_update_delegated_atime(inode);
+               attr->ia_valid &= ~ATTR_ATIME;
        }
 
        /* Optimization: if the end result is no change, don't RPC */