Changeset 368ee04 in mainline for uspace/srv/vfs/vfs_node.c

Timestamp:

2017-04-05T18:10:39Z (8 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

93ad8166

Parents:

39f892a9 (diff), 2166728 (diff)
Note: this is a merge changeset, the changes displayed below correspond to the merge itself.
Use the (diff) links above to see all the changes relative to each parent.

Message:

Merge from lp:~jakub/helenos/vfs-2.5-cherrypick

This merge cherry-picks some of the changesets from Jiri Zarevucky's:

lp:~zarevucky-jiri/helenos/vfs-2.5

and then continues independently, yet sometime in a similar vein.

Roughly speaking, Jiri's branch is merged entirely up to its revision
1926 and then cherry-picked on and off until its revision 1965. Among
these changes are:

• relativization of the API,
• client-side roots,
• server-side mounts,
• inbox for passing arbitrary files from parent to child,
• some streamlining and cleanup.

Additional changes include:

• addressing issues introduced by the above changes,
• client-side I/O cursors (file positions),
• all HelenOS file system APIs begin with the vfs_ prefix and can be used after including vfs/vfs.h,
• removal of some POSIX-ish headers and definitions,
• additional cleanup.

File:

• uspace/srv/vfs/vfs_node.c (modified) (7 diffs)

uspace/srv/vfs/vfs_node.c

@@ -45 +45 @@
 #include <async.h>
 #include <errno.h>
+#include <macros.h>
 
 /** Mutex protecting the VFS node hash table. */
@@ -106 +107 @@
 void vfs_node_delref(vfs_node_t *node)
 {
-        bool free_vfs_node = false;
-        bool free_fs_node = false;
-        
-        fibril_mutex_lock(&nodes_mutex);
-        
-        if (node->refcnt-- == 1) {
-                
+        bool free_node = false;
+        
+        fibril_mutex_lock(&nodes_mutex);
+        
+        node->refcnt--;
+        if (node->refcnt == 0) {
                 /*
                  * We are dropping the last reference to this node.
@@ -119 +119 @@
                 
                 hash_table_remove_item(&nodes, &node->nh_link);
-                free_vfs_node = true;
-                
-                if (!node->lnkcnt)
-                        free_fs_node = true;
+                free_node = true;
         }
         
         fibril_mutex_unlock(&nodes_mutex);
         
-        if (free_fs_node) {
-                
+        if (free_node) {
                 /*
-                 * The node is not visible in the file system namespace.
-                 * Free up its resources.
+                 * VFS_OUT_DESTROY will free up the file's resources if there
+                 * are no more hard links.
                  */
                 
                 async_exch_t *exch = vfs_exchange_grab(node->fs_handle);
-                sysarg_t rc = async_req_2_0(exch, VFS_OUT_DESTROY,
-                    (sysarg_t) node->service_id, (sysarg_t)node->index);
-                
-                assert(rc == EOK);
+                async_msg_2(exch, VFS_OUT_DESTROY, (sysarg_t) node->service_id,
+                    (sysarg_t)node->index);
                 vfs_exchange_release(exch);
+
+                free(node);
         }
-        
-        if (free_vfs_node)
-                free(node);
 }
 
@@ -190 +183 @@
                 node->index = result->triplet.index;
                 node->size = result->size;
-                node->lnkcnt = result->lnkcnt;
                 node->type = result->type;
                 fibril_rwlock_initialize(&node->contents_rwlock);
@@ -196 +188 @@
         } else {
                 node = hash_table_get_inst(tmp, vfs_node_t, nh_link);
-                if (node->type == VFS_NODE_UNKNOWN &&
-                    result->type != VFS_NODE_UNKNOWN) {
-                        /* Upgrade the node type. */
-                        node->type = result->type;
-                }
         }
 
-        assert(node->size == result->size || node->type != VFS_NODE_FILE);
-        assert(node->lnkcnt == result->lnkcnt);
-        assert(node->type == result->type || result->type == VFS_NODE_UNKNOWN);
-
         _vfs_node_addref(node);
+        fibril_mutex_unlock(&nodes_mutex);
+
+        return node;
+}
+
+vfs_node_t *vfs_node_peek(vfs_lookup_res_t *result)
+{
+        vfs_node_t *node = NULL;
+
+        fibril_mutex_lock(&nodes_mutex);
+        ht_link_t *tmp = hash_table_find(&nodes, &result->triplet);
+        if (tmp) {
+                node = hash_table_get_inst(tmp, vfs_node_t, nh_link);
+                _vfs_node_addref(node);
+        }
         fibril_mutex_unlock(&nodes_mutex);
 
@@ -302 +300 @@
         vfs_triplet_t *tri = key;
         vfs_node_t *node = hash_table_get_inst(item, vfs_node_t, nh_link);
-        return node->fs_handle == tri->fs_handle 
-                && node->service_id == tri->service_id
-                && node->index == tri->index;
+        return node->fs_handle == tri->fs_handle &&
+            node->service_id == tri->service_id && node->index == tri->index;
 }
 
@@ -318 +315 @@
 }
 
+bool vfs_node_has_children(vfs_node_t *node)
+{
+        async_exch_t *exch = vfs_exchange_grab(node->fs_handle);
+        int rc = async_req_2_0(exch, VFS_OUT_IS_EMPTY, node->service_id,
+            node->index);
+        vfs_exchange_release(exch);
+        return rc == ENOTEMPTY;
+}
+
 /**
  * @}