NFSv4: Defer inode revalidation when setting up a delegation

Currently we force a synchronous call to __nfs_revalidate_inode() in
nfs_inode_set_delegation(). This not only ensures that we cannot call
nfs_inode_set_delegation from an asynchronous context, but it also slows
down any call to open().

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

diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c
index 56f4f6a..20ac403 100644 (file)
--- a/fs/nfs/delegation.c
+++ b/fs/nfs/delegation.c
@@ -124,10 +124,6 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct
        struct nfs_delegation *delegation;
        int status = 0;
 
-       /* Ensure we first revalidate the attributes and page cache! */
-       if ((nfsi->cache_validity & (NFS_INO_REVAL_PAGECACHE|NFS_INO_INVALID_ATTR)))
-               __nfs_revalidate_inode(NFS_SERVER(inode), inode);
-
        delegation = kmalloc(sizeof(*delegation), GFP_KERNEL);
        if (delegation == NULL)
                return -ENOMEM;
@@ -154,6 +150,12 @@ int nfs_inode_set_delegation(struct inode *inode, struct rpc_cred *cred, struct
                        status = -EIO;
                }
        }
+
+       /* Ensure we revalidate the attributes and page cache! */
+       spin_lock(&inode->i_lock);
+       nfsi->cache_validity |= NFS_INO_REVAL_FORCED;
+       spin_unlock(&inode->i_lock);
+
        spin_unlock(&clp->cl_lock);
        kfree(delegation);
        return status;

diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 9d51241..3d9fccf 100644 (file)
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -1072,8 +1072,10 @@ static int nfs_update_inode(struct inode *inode, struct nfs_fattr *fattr)
                invalid &= ~NFS_INO_INVALID_DATA;
        if (data_stable)
                invalid &= ~(NFS_INO_INVALID_ATTR|NFS_INO_INVALID_ATIME|NFS_INO_REVAL_PAGECACHE);
-       if (!nfs_have_delegation(inode, FMODE_READ))
+       if (!nfs_have_delegation(inode, FMODE_READ) ||
+                       (nfsi->cache_validity & NFS_INO_REVAL_FORCED))
                nfsi->cache_validity |= invalid;
+       nfsi->cache_validity &= ~NFS_INO_REVAL_FORCED;
 
        return 0;
  out_changed:

diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index cf39535..e949710 100644 (file)
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -184,6 +184,7 @@ struct nfs_inode {
 #define NFS_INO_INVALID_ACCESS 0x0008          /* cached access cred invalid */
 #define NFS_INO_INVALID_ACL    0x0010          /* cached acls are invalid */
 #define NFS_INO_REVAL_PAGECACHE        0x0020          /* must revalidate pagecache */
+#define NFS_INO_REVAL_FORCED   0x0040          /* force revalidation ignoring a delegation */
 
 /*
  * Bit offsets in flags field