Changeset 493853ec in mainline

Timestamp:

2009-05-23T16:25:58Z (16 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

ac23b9d3

Parents:

4ef6645

Message:

Hold the namespace rwlock during the entire operation of vfs_mount_internal().
Get rid of rootfs futex, which is not needed anymore.
Do not instantiate VFS node for the mounted root if the mount failed.

File:

• uspace/srv/vfs/vfs_ops.c (modified) (13 diffs)

uspace/srv/vfs/vfs_ops.c

@@ -75 +75 @@
 RWLOCK_INITIALIZE(namespace_rwlock);
 
-futex_t rootfs_futex = FUTEX_INITIALIZER;
 vfs_pair_t rootfs = {
         .fs_handle = 0,
@@ -96 +95 @@
         ipc_call_t answer;
                         
-
         /* Resolve the path to the mountpoint. */
-        futex_down(&rootfs_futex);
+        rwlock_write_lock(&namespace_rwlock);
         if (rootfs.fs_handle) {
                 /* We already have the root FS. */
-                rwlock_write_lock(&namespace_rwlock);
                 if (str_cmp(mp, "/") == 0) {
                         /* Trying to mount root FS over root FS */
+                        ipc_answer_0(rid, EBUSY);
                         rwlock_write_unlock(&namespace_rwlock);
-                        futex_up(&rootfs_futex);
-                        ipc_answer_0(rid, EBUSY);
                         return;
                 }
@@ -113 +109 @@
                 if (rc != EOK) {
                         /* The lookup failed for some reason. */
+                        ipc_answer_0(rid, rc);
                         rwlock_write_unlock(&namespace_rwlock);
-                        futex_up(&rootfs_futex);
-                        ipc_answer_0(rid, rc);
                         return;
                 }
@@ -121 +116 @@
                 mp_node = vfs_node_get(&mp_res);
                 if (!mp_node) {
+                        ipc_answer_0(rid, ENOMEM);
                         rwlock_write_unlock(&namespace_rwlock);
-                        futex_up(&rootfs_futex);
-                        ipc_answer_0(rid, ENOMEM);
                         return;
                 }
@@ -132 +126 @@
                  * This prevents the mount point from being deleted.
                  */
-                rwlock_write_unlock(&namespace_rwlock);
         } else {
                 /* We still don't have the root file system mounted. */
@@ -151 +144 @@
                                 async_wait_for(msg, NULL);
                                 vfs_release_phone(phone);
-                                futex_up(&rootfs_futex);
                                 ipc_answer_0(rid, rc);
+                                rwlock_write_unlock(&namespace_rwlock);
                                 return;
                         }
@@ -159 +152 @@
                         
                         if (rc != EOK) {
-                                futex_up(&rootfs_futex);
                                 ipc_answer_0(rid, rc);
+                                rwlock_write_unlock(&namespace_rwlock);
                                 return;
                         }
@@ -177 +170 @@
                         rootfs.fs_handle = fs_handle;
                         rootfs.dev_handle = dev_handle;
-                        futex_up(&rootfs_futex);
                         
                         /* Add reference to the mounted root. */
@@ -184 +176 @@
                         
                         ipc_answer_0(rid, rc);
+                        rwlock_write_unlock(&namespace_rwlock);
                         return;
                 } else {
@@ -190 +183 @@
                          * being mounted first.
                          */
-                        futex_up(&rootfs_futex);
                         ipc_answer_0(rid, ENOENT);
+                        rwlock_write_unlock(&namespace_rwlock);
                         return;
                 }
         }
-        futex_up(&rootfs_futex);
         
         /*
@@ -222 +214 @@
                         vfs_node_put(mp_node);
                 ipc_answer_0(rid, rc);
+                rwlock_write_unlock(&namespace_rwlock);
                 return;
         }
@@ -234 +227 @@
                         vfs_node_put(mp_node);
                 ipc_answer_0(rid, rc);
+                rwlock_write_unlock(&namespace_rwlock);
                 return;
         }
@@ -239 +233 @@
         vfs_release_phone(phone);
         
-        if (rc != EOK) {
+        if (rc == EOK) {
+                rindex = (fs_index_t) IPC_GET_ARG1(answer);
+                rsize = (size_t) IPC_GET_ARG2(answer);
+                rlnkcnt = (unsigned) IPC_GET_ARG3(answer);
+        
+                mr_res.triplet.fs_handle = fs_handle;
+                mr_res.triplet.dev_handle = dev_handle;
+                mr_res.triplet.index = rindex;
+                mr_res.size = rsize;
+                mr_res.lnkcnt = rlnkcnt;
+                mr_res.type = VFS_NODE_DIRECTORY;
+        
+                /* Add reference to the mounted root. */
+                mr_node = vfs_node_get(&mr_res); 
+                assert(mr_node);
+        } else {
                 /* Mount failed, drop reference to mp_node. */
                 if (mp_node)
                         vfs_node_put(mp_node);
         }
-        
-        rindex = (fs_index_t) IPC_GET_ARG1(answer);
-        rsize = (size_t) IPC_GET_ARG2(answer);
-        rlnkcnt = (unsigned) IPC_GET_ARG3(answer);
-        
-        mr_res.triplet.fs_handle = fs_handle;
-        mr_res.triplet.dev_handle = dev_handle;
-        mr_res.triplet.index = rindex;
-        mr_res.size = rsize;
-        mr_res.lnkcnt = rlnkcnt;
-        mr_res.type = VFS_NODE_DIRECTORY;
-        
-        /* Add reference to the mounted root. */
-        mr_node = vfs_node_get(&mr_res); 
-        assert(mr_node);
 
         ipc_answer_0(rid, rc);
+        rwlock_write_unlock(&namespace_rwlock);
 }