From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001

From: Michael Chang <mchang@suse.com>

Date: Thu, 21 Aug 2014 03:39:11 +0000

Subject: [PATCH] grub2-btrfs-03-follow_default

---

 grub-core/fs/btrfs.c | 107 ++++++++++++++++++++++++++++++++++++---------------

 1 file changed, 76 insertions(+), 31 deletions(-)

diff --git a/grub-core/fs/btrfs.c b/grub-core/fs/btrfs.c

index ad1b56b716d..113c1f746c9 100644

--- a/grub-core/fs/btrfs.c

+++ b/grub-core/fs/btrfs.c

@@ -1256,6 +1256,7 @@ grub_btrfs_mount (grub_device_t dev)

 {

   struct grub_btrfs_data *data;

   grub_err_t err;

+  const char *relpath = grub_env_get ("btrfs_relative_path");

   if (!dev->disk)

     {

@@ -1286,11 +1287,14 @@ grub_btrfs_mount (grub_device_t dev)

   data->devices_attached[0].dev = dev;

   data->devices_attached[0].id = data->sblock.this_device.device_id;

-  err = btrfs_handle_subvol (data);

-  if (err)

+  if (relpath && (relpath[0] == '1' || relpath[0] == 'y'))

     {

-      grub_free (data);

-      return NULL;

+      err = btrfs_handle_subvol (data);

+      if (err)

+      {

+        grub_free (data);

+        return NULL;

+      }

     }

   return data;

@@ -1855,24 +1859,39 @@ find_path (struct grub_btrfs_data *data,

   grub_size_t allocated = 0;

   struct grub_btrfs_dir_item *direl = NULL;

   struct grub_btrfs_key key_out;

+  int follow_default;

   const char *ctoken;

   grub_size_t ctokenlen;

   char *path_alloc = NULL;

   char *origpath = NULL;

   unsigned symlinks_max = 32;

+  const char *relpath = grub_env_get ("btrfs_relative_path");

+  follow_default = 0;

   origpath = grub_strdup (path);

   if (!origpath)

     return grub_errno;

-  if (data->fs_tree)

+  if (relpath && (relpath[0] == '1' || relpath[0] == 'y'))

     {

-      *type = GRUB_BTRFS_DIR_ITEM_TYPE_DIRECTORY;

-      *tree = data->fs_tree;

-      /* This is a tree root, so everything starts at objectid 256 */

-      key->object_id = grub_cpu_to_le64_compile_time (GRUB_BTRFS_OBJECT_ID_CHUNK);

-      key->type = GRUB_BTRFS_ITEM_TYPE_DIR_ITEM;

-      key->offset = 0;

+      if (data->fs_tree)

+        {

+          *type = GRUB_BTRFS_DIR_ITEM_TYPE_DIRECTORY;

+          *tree = data->fs_tree;

+          /* This is a tree root, so everything starts at objectid 256 */

+          key->object_id = grub_cpu_to_le64_compile_time (GRUB_BTRFS_OBJECT_ID_CHUNK);

+          key->type = GRUB_BTRFS_ITEM_TYPE_DIR_ITEM;

+          key->offset = 0;

+        }

+      else

+        {

+          *type = GRUB_BTRFS_DIR_ITEM_TYPE_DIRECTORY;

+          *tree = data->sblock.root_tree;

+          key->object_id = data->sblock.root_dir_objectid;

+          key->type = GRUB_BTRFS_ITEM_TYPE_DIR_ITEM;

+          key->offset = 0;

+          follow_default = 1;

+        }

     }

   else

     {

@@ -1883,15 +1902,23 @@ find_path (struct grub_btrfs_data *data,

   while (1)

     {

-      while (path[0] == '/')

-	path++;

-      if (!path[0])

-	break;

-      slash = grub_strchr (path, '/');

-      if (!slash)

-	slash = path + grub_strlen (path);

-      ctoken = path;

-      ctokenlen = slash - path;

+      if (!follow_default)

+	{

+	  while (path[0] == '/')

+	    path++;

+	  if (!path[0])

+	    break;

+	  slash = grub_strchr (path, '/');

+	  if (!slash)

+	    slash = path + grub_strlen (path);

+	  ctoken = path;

+	  ctokenlen = slash - path;

+	}

+      else

+	{

+	  ctoken = "default";

+	  ctokenlen = sizeof ("default") - 1;

+	}

       if (*type != GRUB_BTRFS_DIR_ITEM_TYPE_DIRECTORY)

 	{

@@ -1902,7 +1929,9 @@ find_path (struct grub_btrfs_data *data,

       if (ctokenlen == 1 && ctoken[0] == '.')

 	{

-	  path = slash;

+	  if (!follow_default)

+	    path = slash;

+	  follow_default = 0;

 	  continue;

 	}

       if (ctokenlen == 2 && ctoken[0] == '.' && ctoken[1] == '.')

@@ -1933,8 +1962,9 @@ find_path (struct grub_btrfs_data *data,

 	  *type = GRUB_BTRFS_DIR_ITEM_TYPE_DIRECTORY;

 	  key->object_id = key_out.offset;

-	  path = slash;

-

+	  if (!follow_default)

+	    path = slash;

+	  follow_default = 0;

 	  continue;

 	}

@@ -2003,7 +2033,9 @@ find_path (struct grub_btrfs_data *data,

 	  return err;

 	}

-      path = slash;

+      if (!follow_default)

+	path = slash;

+      follow_default = 0;

       if (cdirel->type == GRUB_BTRFS_DIR_ITEM_TYPE_SYMLINK)

 	{

 	  struct grub_btrfs_inode inode;

@@ -2053,14 +2085,26 @@ find_path (struct grub_btrfs_data *data,

 	  path = path_alloc = tmp;

 	  if (path[0] == '/')

 	    {

-	      if (data->fs_tree)

+              if (relpath && (relpath[0] == '1' || relpath[0] == 'y'))

 		{

-		  *type = GRUB_BTRFS_DIR_ITEM_TYPE_DIRECTORY;

-		  *tree = data->fs_tree;

-		  /* This is a tree root, so everything starts at objectid 256 */

-		  key->object_id = grub_cpu_to_le64_compile_time (GRUB_BTRFS_OBJECT_ID_CHUNK);

-		  key->type = GRUB_BTRFS_ITEM_TYPE_DIR_ITEM;

-		  key->offset = 0;

+	          if (data->fs_tree)

+		    {

+		      *type = GRUB_BTRFS_DIR_ITEM_TYPE_DIRECTORY;

+		      *tree = data->fs_tree;

+		      /* This is a tree root, so everything starts at objectid 256 */

+		      key->object_id = grub_cpu_to_le64_compile_time (GRUB_BTRFS_OBJECT_ID_CHUNK);

+		      key->type = GRUB_BTRFS_ITEM_TYPE_DIR_ITEM;

+		      key->offset = 0;

+		    }

+		  else

+		    {

+	              *type = GRUB_BTRFS_DIR_ITEM_TYPE_DIRECTORY;

+	              *tree = data->sblock.root_tree;

+	              key->object_id = data->sblock.root_dir_objectid;

+	              key->type = GRUB_BTRFS_ITEM_TYPE_DIR_ITEM;

+	              key->offset = 0;

+	              follow_default = 1;

+		    }

 		}

 	      else

 		{

@@ -2716,6 +2760,7 @@ GRUB_MOD_INIT (btrfs)

                                subvolid_set_env);

   grub_env_export ("btrfs_subvol");

   grub_env_export ("btrfs_subvolid");

+  grub_env_export ("btrfs_relative_path");

 }

 GRUB_MOD_FINI (btrfs)