diff mbox

nfs: Fix handling of change_attr updates in nfs_update_inode()

Message ID 1403268301-29719-1-git-send-email-smayhew@redhat.com (mailing list archive)
State New, archived
Headers show

Commit Message

Scott Mayhew June 20, 2014, 12:45 p.m. UTC
When we detect that the change attribute has changed on the server, it's
only necessary to invalidate our caches if we're not holding a write
delegation.  Otherwise, the change attribute is changing as the result
of our modifications and we can just silently update our copy.

Signed-off-by: Scott Mayhew <smayhew@redhat.com>
---
 fs/nfs/inode.c | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

Comments

Trond Myklebust June 20, 2014, 3:31 p.m. UTC | #1
On Fri, Jun 20, 2014 at 8:45 AM, Scott Mayhew <smayhew@redhat.com> wrote:
> When we detect that the change attribute has changed on the server, it's
> only necessary to invalidate our caches if we're not holding a write
> delegation.  Otherwise, the change attribute is changing as the result
> of our modifications and we can just silently update our copy.
>
> Signed-off-by: Scott Mayhew <smayhew@redhat.com>
> ---
>  fs/nfs/inode.c | 20 +++++++++++---------
>  1 file changed, 11 insertions(+), 9 deletions(-)
>
> diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
> index c496f8a..186562d 100644
> --- a/fs/nfs/inode.c
> +++ b/fs/nfs/inode.c
> @@ -1563,15 +1563,17 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
>         /* More cache consistency checks */
>         if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {
>                 if (inode->i_version != fattr->change_attr) {
> -                       dprintk("NFS: change_attr change on server for file %s/%ld\n",
> -                                       inode->i_sb->s_id, inode->i_ino);
> -                       invalid |= NFS_INO_INVALID_ATTR
> -                               | NFS_INO_INVALID_DATA
> -                               | NFS_INO_INVALID_ACCESS
> -                               | NFS_INO_INVALID_ACL
> -                               | NFS_INO_REVAL_PAGECACHE;
> -                       if (S_ISDIR(inode->i_mode))
> -                               nfs_force_lookup_revalidate(inode);
> +                       if (!NFS_PROTO(inode)->have_delegation(inode, FMODE_WRITE)) {
> +                               dprintk("NFS: change_attr change on server for file %s/%ld\n",
> +                                               inode->i_sb->s_id, inode->i_ino);
> +                               invalid |= NFS_INO_INVALID_ATTR
> +                                       | NFS_INO_INVALID_DATA
> +                                       | NFS_INO_INVALID_ACCESS
> +                                       | NFS_INO_INVALID_ACL
> +                                       | NFS_INO_REVAL_PAGECACHE;
> +                               if (S_ISDIR(inode->i_mode))
> +                                       nfs_force_lookup_revalidate(inode);
> +                       }
>                         inode->i_version = fattr->change_attr;
>                 }
>         } else if (server->caps & NFS_CAP_CHANGE_ATTR)
> --
> 1.9.3
>

Hi Scott,

This circumvents the INO_REVAL_FORCED flag, which is set in those
situations where the changes to the file are not a priori known to be
covered by the delegation.

In either case, we already have the check for ->have_delegation()
before deciding whether or not to apply the 'invalid' flags to
nfsi->cache_validity at the end of the function.

Cheers
  Trond
diff mbox

Patch

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index c496f8a..186562d 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -1563,15 +1563,17 @@  static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
 	/* More cache consistency checks */
 	if (fattr->valid & NFS_ATTR_FATTR_CHANGE) {
 		if (inode->i_version != fattr->change_attr) {
-			dprintk("NFS: change_attr change on server for file %s/%ld\n",
-					inode->i_sb->s_id, inode->i_ino);
-			invalid |= NFS_INO_INVALID_ATTR
-				| NFS_INO_INVALID_DATA
-				| NFS_INO_INVALID_ACCESS
-				| NFS_INO_INVALID_ACL
-				| NFS_INO_REVAL_PAGECACHE;
-			if (S_ISDIR(inode->i_mode))
-				nfs_force_lookup_revalidate(inode);
+			if (!NFS_PROTO(inode)->have_delegation(inode, FMODE_WRITE)) {
+				dprintk("NFS: change_attr change on server for file %s/%ld\n",
+						inode->i_sb->s_id, inode->i_ino);
+				invalid |= NFS_INO_INVALID_ATTR
+					| NFS_INO_INVALID_DATA
+					| NFS_INO_INVALID_ACCESS
+					| NFS_INO_INVALID_ACL
+					| NFS_INO_REVAL_PAGECACHE;
+				if (S_ISDIR(inode->i_mode))
+					nfs_force_lookup_revalidate(inode);
+			}
 			inode->i_version = fattr->change_attr;
 		}
 	} else if (server->caps & NFS_CAP_CHANGE_ATTR)