NFS: Clean up weak cache consistency code

 ...and ensure that nfs_update_inode() respects wcc

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

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 2c7f8aac1deca61a72eb0f2bb2b8296654eec4db..7270b1d73d3056829b15d0fb5d44013d1634be6a 100644 (file)
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -1248,6 +1248,33 @@ void nfs_end_data_update(struct inode *inode)
        atomic_dec(&nfsi->data_updates);
 }
 
+static void nfs_wcc_update_inode(struct inode *inode, struct nfs_fattr *fattr)
+{
+       struct nfs_inode *nfsi = NFS_I(inode);
+
+       if ((fattr->valid & NFS_ATTR_PRE_CHANGE) != 0
+                       && nfsi->change_attr == fattr->pre_change_attr) {
+               nfsi->change_attr = fattr->change_attr;
+               nfsi->cache_change_attribute = jiffies;
+       }
+
+       /* If we have atomic WCC data, we may update some attributes */
+       if ((fattr->valid & NFS_ATTR_WCC) != 0) {
+               if (timespec_equal(&inode->i_ctime, &fattr->pre_ctime)) {
+                       memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
+                       nfsi->cache_change_attribute = jiffies;
+               }
+               if (timespec_equal(&inode->i_mtime, &fattr->pre_mtime)) {
+                       memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
+                       nfsi->cache_change_attribute = jiffies;
+               }
+               if (inode->i_size == fattr->pre_size && nfsi->npages == 0) {
+                       inode->i_size = fattr->size;
+                       nfsi->cache_change_attribute = jiffies;
+               }
+       }
+}
+
 /**
  * nfs_check_inode_attributes - verify consistency of the inode attribute cache
  * @inode - pointer to inode
@@ -1264,22 +1291,20 @@ static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fat
        int data_unstable;
 
 
+       if ((fattr->valid & NFS_ATTR_FATTR) == 0)
+               return 0;
+
        /* Are we in the process of updating data on the server? */
        data_unstable = nfs_caches_unstable(inode);
 
-       if (fattr->valid & NFS_ATTR_FATTR_V4) {
-               if ((fattr->valid & NFS_ATTR_PRE_CHANGE) != 0
-                               && nfsi->change_attr == fattr->pre_change_attr)
-                       nfsi->change_attr = fattr->change_attr;
-               if (nfsi->change_attr != fattr->change_attr) {
-                       nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
-                       if (!data_unstable)
-                               nfsi->cache_validity |= NFS_INO_REVAL_PAGECACHE;
-               }
-       }
+       /* Do atomic weak cache consistency updates */
+       nfs_wcc_update_inode(inode, fattr);
 
-       if ((fattr->valid & NFS_ATTR_FATTR) == 0) {
-               return 0;
+       if ((fattr->valid & NFS_ATTR_FATTR_V4) != 0 &&
+                       nfsi->change_attr != fattr->change_attr) {
+               nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
+               if (!data_unstable)
+                       nfsi->cache_validity |= NFS_INO_REVAL_PAGECACHE;
        }
 
        /* Has the inode gone and changed behind our back? */
@@ -1291,14 +1316,6 @@ static int nfs_check_inode_attributes(struct inode *inode, struct nfs_fattr *fat
        cur_size = i_size_read(inode);
        new_isize = nfs_size_to_loff_t(fattr->size);
 
-       /* If we have atomic WCC data, we may update some attributes */
-       if ((fattr->valid & NFS_ATTR_WCC) != 0) {
-               if (timespec_equal(&inode->i_ctime, &fattr->pre_ctime))
-                       memcpy(&inode->i_ctime, &fattr->ctime, sizeof(inode->i_ctime));
-               if (timespec_equal(&inode->i_mtime, &fattr->pre_mtime))
-                       memcpy(&inode->i_mtime, &fattr->mtime, sizeof(inode->i_mtime));
-       }
-
        /* Verify a few of the more important attributes */
        if (!timespec_equal(&inode->i_mtime, &fattr->mtime)) {
                nfsi->cache_validity |= NFS_INO_INVALID_ATTR;
@@ -1426,6 +1443,9 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
        if (data_stable)
                nfsi->cache_validity &= ~(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ATIME);
 
+       /* Do atomic weak cache consistency updates */
+       nfs_wcc_update_inode(inode, fattr);
+
        /* Check if our cached file size is stale */
        new_isize = nfs_size_to_loff_t(fattr->size);
        cur_isize = i_size_read(inode);