NFS: Use information about the change attribute to optimise updates
If the NFSv4.2 server supports the 'change_attr_type' attribute, then
allow the client to optimise its attribute cache update strategy.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 6992c88..0b0a48d 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -1186,10 +1186,23 @@ nfs4_update_changeattr_locked(struct inode *inode,
unsigned long timestamp, unsigned long cache_validity)
{
struct nfs_inode *nfsi = NFS_I(inode);
+ u64 change_attr = inode_peek_iversion_raw(inode);
cache_validity |= NFS_INO_INVALID_CTIME | NFS_INO_INVALID_MTIME;
- if (cinfo->atomic && cinfo->before == inode_peek_iversion_raw(inode)) {
+ 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)
+ goto out;
+ break;
+ default:
+ if ((s64)(change_attr - cinfo->after) >= 0)
+ goto out;
+ }
+
+ if (cinfo->atomic && cinfo->before == change_attr) {
nfsi->attrtimeo_timestamp = jiffies;
} else {
if (S_ISDIR(inode->i_mode)) {
@@ -1201,7 +1214,7 @@ nfs4_update_changeattr_locked(struct inode *inode,
cache_validity |= NFS_INO_REVAL_PAGECACHE;
}
- if (cinfo->before != inode_peek_iversion_raw(inode))
+ if (cinfo->before != change_attr)
cache_validity |= NFS_INO_INVALID_ACCESS |
NFS_INO_INVALID_ACL |
NFS_INO_INVALID_XATTR;
@@ -1209,8 +1222,9 @@ nfs4_update_changeattr_locked(struct inode *inode,
inode_set_iversion_raw(inode, cinfo->after);
nfsi->read_cache_jiffies = timestamp;
nfsi->attr_gencount = nfs_inc_attr_generation_counter();
- nfs_set_cache_invalid(inode, cache_validity);
nfsi->cache_validity &= ~NFS_INO_INVALID_CHANGE;
+out:
+ nfs_set_cache_invalid(inode, cache_validity);
}
void