vfs: functions to change a vnode busy status and ID

The kernel version is only partially tested.

Change-Id: I9a2f6c78087154ab137eadbced99062a8a2dd688
Reviewed-on: https://review.haiku-os.org/c/918
Reviewed-by: waddlesplash <[email protected]>

headers/os/drivers/fs_interface.h

@@ -330,6 +330,8 @@ extern status_t remove_vnode(fs_volume* volume, ino_t vnodeID);
 extern status_t unremove_vnode(fs_volume* volume, ino_t vnodeID);
 extern status_t get_vnode_removed(fs_volume* volume, ino_t vnodeID,
 					bool* _removed);
+extern status_t mark_vnode_busy(fs_volume* volume, ino_t vnodeID, bool busy);
+extern status_t change_vnode_id(fs_volume* volume, ino_t vnodeID, ino_t newID);
 extern fs_volume* volume_for_vnode(fs_vnode* vnode);
 extern status_t check_access_permissions(int accessMode, mode_t mode,
 					gid_t nodeGroupID, uid_t nodeUserID);

headers/private/fs_shell/fssh_api_wrapper.h

@@ -944,6 +944,8 @@
 #define remove_vnode				fssh_remove_vnode
 #define unremove_vnode				fssh_unremove_vnode
 #define get_vnode_removed			fssh_get_vnode_removed
+#define mark_vnode_busy				fssh_mark_vnode_busy
+#define change_vnode_id				fssh_change_vnode_id
 #define volume_for_vnode			fssh_volume_for_vnode
 #define check_access_permissions	fssh_check_access_permissions
 #define read_pages					fssh_read_pages

headers/private/fs_shell/fssh_fs_interface.h

@@ -360,6 +360,10 @@ extern fssh_status_t fssh_unremove_vnode(fssh_fs_volume *volume,
 				fssh_vnode_id vnodeID);
 extern fssh_status_t fssh_get_vnode_removed(fssh_fs_volume *volume,
 				fssh_vnode_id vnodeID, bool* removed);
+extern fssh_status_t fssh_mark_vnode_busy(fssh_fs_volume* volume,
+				fssh_vnode_id vnodeID, bool busy);
+extern fssh_status_t fssh_change_vnode_id(fssh_fs_volume* volume,
+				fssh_vnode_id vnodeID, fssh_vnode_id newID);
 extern fssh_fs_volume* fssh_volume_for_vnode(fssh_fs_vnode *vnode);
 extern fssh_status_t fssh_check_access_permissions(int accessMode,
 				fssh_mode_t mode, fssh_gid_t nodeGroupID,

src/system/kernel/cache/vnode_store.h

@@ -52,6 +52,8 @@ public:
 									{ return fDevice; }
 			ino_t				InodeId() const
 									{ return fInode; }
+			void				SetVnodeID(ino_t id)
+									{ fInode = id; }
 
 protected:
 	virtual	void				DeleteObject();

src/system/kernel/fs/vfs.cpp

@@ -3981,6 +3981,47 @@ get_vnode_removed(fs_volume* volume, ino_t vnodeID, bool* _removed)
 }
 
 
+extern "C" status_t
+mark_vnode_busy(fs_volume* volume, ino_t vnodeID, bool busy)
+{
+	ReadLocker locker(sVnodeLock);
+
+	struct vnode* vnode = lookup_vnode(volume->id, vnodeID);
+	if (vnode == NULL)
+		return B_ENTRY_NOT_FOUND;
+
+	// are we trying to mark an already busy node busy again?
+	if (busy && vnode->IsBusy())
+		return B_BUSY;
+
+	vnode->Lock();
+	vnode->SetBusy(busy);
+	vnode->Unlock();
+
+	return B_OK;
+}
+
+
+extern "C" status_t
+change_vnode_id(fs_volume* volume, ino_t vnodeID, ino_t newID)
+{
+	WriteLocker locker(sVnodeLock);
+
+	struct vnode* vnode = lookup_vnode(volume->id, vnodeID);
+	if (vnode == NULL)
+		return B_ENTRY_NOT_FOUND;
+
+	sVnodeTable->Remove(vnode);
+	vnode->id = newID;
+	sVnodeTable->Insert(vnode);
+
+	if (vnode->cache != NULL)
+		((VMVnodeCache*)vnode->cache)->SetVnodeID(newID);
+
+	return B_OK;
+}
+
+
 extern "C" fs_volume*
 volume_for_vnode(fs_vnode* _vnode)
 {

src/tools/fs_shell/vfs.cpp

@@ -2117,6 +2117,51 @@ fssh_get_vnode_removed(fssh_fs_volume *volume, fssh_vnode_id vnodeID, bool* remo
 }
 
 
+extern "C" fssh_status_t
+fssh_mark_vnode_busy(fssh_fs_volume* volume, fssh_vnode_id vnodeID, bool busy)
+{
+	fssh_mutex_lock(&sVnodeMutex);
+
+	struct vnode* vnode = lookup_vnode(volume->id, vnodeID);
+	if (vnode == NULL) {
+		fssh_mutex_unlock(&sVnodeMutex);
+		return FSSH_B_ENTRY_NOT_FOUND;
+	}
+
+	// are we trying to mark an already busy node busy again?
+	if (busy && vnode->busy) {
+		fssh_mutex_unlock(&sVnodeMutex);
+		return FSSH_B_BUSY;
+	}
+
+	vnode->busy = busy;
+
+	fssh_mutex_unlock(&sVnodeMutex);
+	return FSSH_B_OK;
+}
+
+
+extern "C" fssh_status_t
+fssh_change_vnode_id(fssh_fs_volume* volume, fssh_vnode_id vnodeID,
+	fssh_vnode_id newID)
+{
+	fssh_mutex_lock(&sVnodeMutex);
+
+	struct vnode* vnode = lookup_vnode(volume->id, vnodeID);
+	if (vnode == NULL) {
+		fssh_mutex_unlock(&sVnodeMutex);
+		return FSSH_B_ENTRY_NOT_FOUND;
+	}
+
+	hash_remove(sVnodeTable, vnode);
+	vnode->id = newID;
+	hash_insert(sVnodeTable, vnode);
+
+	fssh_mutex_unlock(&sVnodeMutex);
+	return FSSH_B_OK;
+}
+
+
 extern "C" fssh_fs_volume*
 fssh_volume_for_vnode(fssh_fs_vnode *_vnode)
 {