Changeset b17186d in mainline for uspace/srv/vfs/vfs_ops.c

Timestamp:

2008-11-29T15:39:24Z (15 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

dfd77382

Parents:

abd36f7

Message:

Hold the namespace_rwlock during readdir().

File:

• uspace/srv/vfs/vfs_ops.c (modified) (5 diffs)

uspace/srv/vfs/vfs_ops.c

@@ -235 +235 @@
                         mr_res.size = (size_t) rsize;
                         mr_res.lnkcnt = (unsigned) rlnkcnt;
+                        mr_res.type = VFS_NODE_DIRECTORY;
 
                         rootfs.fs_handle = fs_handle;
@@ -302 +303 @@
         int mode = IPC_GET_ARG3(*request);
         size_t len;
+
+        /*
+         * Make sure that we are called with exactly one of L_FILE and
+         * L_DIRECTORY.
+         */
+        if ((lflag & (L_FILE | L_DIRECTORY)) == 0 ||
+            (lflag & (L_FILE | L_DIRECTORY)) == (L_FILE | L_DIRECTORY)) {
+                ipc_answer_0(rid, EINVAL);
+                return;
+        }
 
         if (oflag & O_CREAT)
@@ -457 +468 @@
          */
         futex_down(&file->lock);
-        
+
         /*
          * Lock the file's node so that no other client can read/write to it at
@@ -466 +477 @@
         else
                 rwlock_write_lock(&file->node->contents_rwlock);
+
+        if (file->node->type == VFS_NODE_DIRECTORY) {
+                /*
+                 * Make sure that no one is modifying the namespace
+                 * while we are in readdir().
+                 */
+                assert(read);
+                rwlock_read_lock(&namespace_rwlock);
+        }
         
         int fs_phone = vfs_grab_phone(file->node->fs_handle);   
@@ -491 +511 @@
         async_wait_for(msg, &rc);
         size_t bytes = IPC_GET_ARG1(answer);
+
+        if (file->node->type == VFS_NODE_DIRECTORY)
+                rwlock_read_unlock(&namespace_rwlock);
         
         /* Unlock the VFS node. */