NFS: Clean up the write request locking.

Ensure that we set/clear NFS_PAGE_TAG_LOCKED when the nfs_page is hashed.

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

1 files changed, 8 insertions, 5 deletions

diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 345bb9b4765b..3b3dbb94393d 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -111,13 +111,14 @@ void nfs_unlock_request(struct nfs_page *req)
  * nfs_set_page_tag_locked - Tag a request as locked
  * @req:
  */
-static int nfs_set_page_tag_locked(struct nfs_page *req)
+int nfs_set_page_tag_locked(struct nfs_page *req)
 {
         struct nfs_inode *nfsi = NFS_I(req->wb_context->path.dentry->d_inode);
 
-        if (!nfs_lock_request(req))
+        if (!nfs_lock_request_dontget(req))
                 return 0;
-        radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_LOCKED);
+        if (req->wb_page != NULL)
+                radix_tree_tag_set(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_LOCKED);
         return 1;
 }
 
@@ -132,9 +133,10 @@ void nfs_clear_page_tag_locked(struct nfs_page *req)
         if (req->wb_page != NULL) {
                 spin_lock(&inode->i_lock);
                 radix_tree_tag_clear(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_LOCKED);
+                nfs_unlock_request(req);
                 spin_unlock(&inode->i_lock);
-        }
-        nfs_unlock_request(req);
+        } else
+                nfs_unlock_request(req);
 }
 
 /**
@@ -421,6 +423,7 @@ int nfs_scan_list(struct nfs_inode *nfsi,
                                 goto out;
                         idx_start = req->wb_index + 1;
                         if (nfs_set_page_tag_locked(req)) {
+                                kref_get(&req->wb_kref);
                                 nfs_list_remove_request(req);
                                 radix_tree_tag_clear(&nfsi->nfs_page_tree,
                                                 req->wb_index, tag);