NFS: Fix a race with PG_private and nfs_release_page()

[linux-2.6] / fs / nfs / pagelist.c

diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index d6e076c9dbe13b91ab47f598b97625614140750f..106aca388ebc20288f5435d114012a28bf7d433c 100644 (file)
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -88,7 +88,6 @@ nfs_create_request(struct nfs_open_context *ctx, struct inode *inode,
        BUG_ON(PagePrivate(page));
        BUG_ON(!PageLocked(page));
        BUG_ON(page->mapping->host != inode);
-       SetPagePrivate(page);
        req->wb_offset  = offset;
        req->wb_pgbase  = offset;
        req->wb_bytes   = count;
@@ -136,9 +135,11 @@ void nfs_clear_page_writeback(struct nfs_page *req)
 {
        struct nfs_inode *nfsi = NFS_I(req->wb_context->dentry->d_inode);
 
-       spin_lock(&nfsi->req_lock);
-       radix_tree_tag_clear(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_WRITEBACK);
-       spin_unlock(&nfsi->req_lock);
+       if (req->wb_page != NULL) {
+               spin_lock(&nfsi->req_lock);
+               radix_tree_tag_clear(&nfsi->nfs_page_tree, req->wb_index, NFS_PAGE_TAG_WRITEBACK);
+               spin_unlock(&nfsi->req_lock);
+       }
        nfs_unlock_request(req);
 }
 
@@ -153,7 +154,6 @@ void nfs_clear_request(struct nfs_page *req)
 {
        struct page *page = req->wb_page;
        if (page != NULL) {
-               ClearPagePrivate(page);
                page_cache_release(page);
                req->wb_page = NULL;
        }