NFS: add comments clarifying the use of nfs_post_op_update()

[powerpc.git] / fs / nfs / write.c

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 8ab3cf1..c12effb 100644 (file)
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -396,6 +396,7 @@ int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc)
 out:
        clear_bit(BDI_write_congested, &bdi->state);
        wake_up_all(&nfs_write_congestion);
+       writeback_congestion_end();
        return err;
 }
 
@@ -590,8 +591,8 @@ static void nfs_cancel_commit_list(struct list_head *head)
                req = nfs_list_entry(head->next);
                nfs_list_remove_request(req);
                nfs_inode_remove_request(req);
-               nfs_clear_page_writeback(req);
                dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
+               nfs_clear_page_writeback(req);
        }
 }
 
@@ -1252,7 +1253,13 @@ int nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data)
        dprintk("NFS: %4d nfs_writeback_done (status %d)\n",
                task->tk_pid, task->tk_status);
 
-       /* Call the NFS version-specific code */
+       /*
+        * ->write_done will attempt to use post-op attributes to detect
+        * conflicting writes by other clients.  A strict interpretation
+        * of close-to-open would allow us to continue caching even if
+        * another writer had changed the file, but some applications
+        * depend on tighter cache coherency when writing.
+        */
        status = NFS_PROTO(data->inode)->write_done(task, data);
        if (status != 0)
                return status;
@@ -1273,7 +1280,7 @@ int nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data)
                if (time_before(complain, jiffies)) {
                        dprintk("NFS: faulty NFS server %s:"
                                " (committed = %d) != (stable = %d)\n",
-                               NFS_SERVER(data->inode)->hostname,
+                               NFS_SERVER(data->inode)->nfs_client->cl_hostname,
                                resp->verf->committed, argp->stable);
                        complain = jiffies + 300 * HZ;
                }
@@ -1386,8 +1393,8 @@ nfs_commit_list(struct inode *inode, struct list_head *head, int how)
                req = nfs_list_entry(head->next);
                nfs_list_remove_request(req);
                nfs_mark_request_commit(req);
-               nfs_clear_page_writeback(req);
                dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
+               nfs_clear_page_writeback(req);
        }
        return -ENOMEM;
 }