Changeset f49b0ea in mainline for uspace/srv/vfs/vfs_ops.c

Timestamp:

2008-06-06T15:16:41Z (16 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

cde485d

Parents:

f86c184

Message:

Split the 'mount another filesystem here' and 'you are being mounted and the
device is this' mount semantics. Add VFS_MOUNTED VFS operation that corresponds
to the latter and reserve VFS_MOUNT only for the former. Because of this
change, the VFS server does not maintain the mr_node VFS node for the name space
root anymore and the VFS_LOOKUP operation is now not meant to be used on
unmounted file system, not even for looking up the root node of unmounted file
systems. In the light of these changes, TMPFS is now initialized from
tmpfs_mounted() function.

File:

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

uspace/srv/vfs/vfs_ops.c

@@ -63 +63 @@
 
 futex_t rootfs_futex = FUTEX_INITIALIZER;
-vfs_triplet_t rootfs = {
+vfs_pair_t rootfs = {
         .fs_handle = 0,
-        .dev_handle = 0,
-        .index = 0,
+        .dev_handle = 0
 };
-
-static int
-lookup_root(fs_handle_t fs_handle, dev_handle_t dev_handle,
-    vfs_lookup_res_t *result)
-{
-        vfs_pair_t altroot = {
-                .fs_handle = fs_handle,
-                .dev_handle = dev_handle,
-        };
-
-        return vfs_lookup_internal("/", L_DIRECTORY, result, &altroot);
-}
 
 void vfs_mount(ipc_callid_t rid, ipc_call_t *request)
@@ -164 +151 @@
         buf[size] = '\0';
 
-        /*
-         * Lookup the root node of the filesystem being mounted.
-         * In this case, we don't need to take the namespace_futex as the root
-         * node cannot be removed. However, we do take a reference to it so
-         * that we can track how many times it has been mounted.
-         */
-        vfs_lookup_res_t mr_res;
-        rc = lookup_root(fs_handle, dev_handle, &mr_res);
-        if (rc != EOK) {
-                free(buf);
-                ipc_answer_0(rid, rc);
-                return;
-        }
-        vfs_node_t *mr_node = vfs_node_get(&mr_res);
-        if (!mr_node) {
-                free(buf);
-                ipc_answer_0(rid, ENOMEM);
-                return;
-        }
-
-        /* Finally, we need to resolve the path to the mountpoint. */
+        /* Resolve the path to the mountpoint. */
         vfs_lookup_res_t mp_res;
         futex_down(&rootfs_futex);
@@ -194 +161 @@
                         rwlock_write_unlock(&namespace_rwlock);
                         futex_up(&rootfs_futex);
-                        vfs_node_put(mr_node);
                         free(buf);
                         ipc_answer_0(rid, EBUSY);
@@ -204 +170 @@
                         rwlock_write_unlock(&namespace_rwlock);
                         futex_up(&rootfs_futex);
-                        vfs_node_put(mr_node);  /* failed -> drop reference */
                         free(buf);
                         ipc_answer_0(rid, rc);
@@ -213 +178 @@
                         rwlock_write_unlock(&namespace_rwlock);
                         futex_up(&rootfs_futex);
-                        vfs_node_put(mr_node);  /* failed -> drop reference */
                         free(buf);
                         ipc_answer_0(rid, ENOMEM);
@@ -233 +197 @@
                         free(buf);
                         
-                        /* Inform the mount point about the root mount. */
-                        phone = vfs_grab_phone(mr_res.triplet.fs_handle);
-                        rc = async_req_5_0(phone, VFS_MOUNT,
-                            (ipcarg_t) mr_res.triplet.dev_handle,
-                            (ipcarg_t) mr_res.triplet.index,
-                            (ipcarg_t) mr_res.triplet.fs_handle,
-                            (ipcarg_t) mr_res.triplet.dev_handle,
-                            (ipcarg_t) mr_res.triplet.index);
+                        /* Tell the mountee that it is being mounted. */
+                        phone = vfs_grab_phone(fs_handle);
+                        rc = async_req_1_0(phone, VFS_MOUNTED,
+                            (ipcarg_t) dev_handle);
                         vfs_release_phone(phone);
 
-                        if (rc == EOK)
-                                rootfs = mr_res.triplet;
-                        else 
-                                vfs_node_put(mr_node);
+                        if (rc == EOK) {
+                                rootfs.fs_handle = fs_handle;
+                                rootfs.dev_handle = dev_handle;
+                        }
 
                         futex_up(&rootfs_futex);
@@ -258 +218 @@
                         futex_up(&rootfs_futex);
                         free(buf);
-                        vfs_node_put(mr_node);  /* failed -> drop reference */
                         ipc_answer_0(rid, ENOENT);
                         return;
@@ -269 +228 @@
         /*
          * At this point, we have all necessary pieces: file system and device
-         * handles, and we know the mount point VFS node and also the root node
-         * of the file system being mounted.
-         */
-
-        /**
-         * @todo
-         * Add more IPC parameters so that we can send mount mode/flags.
-         */
+         * handles, and we know the mount point VFS node.
+         */
+
         phone = vfs_grab_phone(mp_res.triplet.fs_handle);
-        rc = async_req_5_0(phone, VFS_MOUNT,
+        rc = async_req_4_0(phone, VFS_MOUNT,
             (ipcarg_t) mp_res.triplet.dev_handle,
             (ipcarg_t) mp_res.triplet.index,
-            (ipcarg_t) mr_res.triplet.fs_handle,
-            (ipcarg_t) mr_res.triplet.dev_handle,
-            (ipcarg_t) mr_res.triplet.index);
+            (ipcarg_t) fs_handle,
+            (ipcarg_t) dev_handle);
         vfs_release_phone(phone);
 
         if (rc != EOK) {
-                /* Mount failed, drop references to mr_node and mp_node. */
-                vfs_node_put(mr_node);
+                /* Mount failed, drop reference to mp_node. */
                 if (mp_node)
                         vfs_node_put(mp_node);