Changeset 2c2e0c6 in mainline for uspace/srv/vfs/vfs_mount.c

Timestamp:

2007-09-28T20:40:56Z (17 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

af0ff9b2

Parents:

7313e7a

Message:

VFS work.
Prevent race conditions when checking rootfs by taking a newly introduced
rootfs_futex.

File:

• uspace/srv/vfs/vfs_mount.c (modified) (8 diffs)

uspace/srv/vfs/vfs_mount.c

@@ -46 +46 @@
 #include "vfs.h"
 
+atomic_t rootfs_futex = FUTEX_INITIALIZER;
 vfs_node_t rootfs = { 0 };
 
@@ -59 +60 @@
         };
 
-        return vfs_lookup_internal("/", 1, root, &altroot);
+        return vfs_lookup_internal("/", strlen("/"), root, &altroot);
 }
 
@@ -150 +151 @@
          */
         vfs_node_t mp;
+        futex_down(&rootfs_futex);
         if (rootfs.fs_handle) {
                 /*
@@ -160 +162 @@
                          * The lookup failed for some reason.
                          */
+                        futex_up(&rootfs_futex);
                         free(buf);
                         ipc_answer_fast(rid, rc, 0, 0);
@@ -168 +171 @@
                  * We still don't have the root file system mounted.
                  */
-                if ((size - FS_NAME_MAXLEN == 1) &&
+                if ((size - FS_NAME_MAXLEN == strlen("/")) &&
                     (buf[FS_NAME_MAXLEN] == '/')) {
                         /*
@@ -174 +177 @@
                          */
                         rootfs = mounted_root;
+                        futex_up(&rootfs_futex);
                         free(buf);
                         ipc_answer_fast(rid, EOK, 0, 0);
@@ -182 +186 @@
                          * being mounted first.
                          */
+                        futex_up(&rootfs_futex);
                         free(buf);
                         ipc_answer_fast(rid, ENOENT, 0, 0);
@@ -187 +192 @@
                 }
         }
-                
+        futex_up(&rootfs_futex);
+        
         /*
          * At this point, we have all necessary pieces: file system and device