1 files changed, 142 insertions, 0 deletions
diff --git a/sys-boot/grub/files/grub2-ext4support-ext2.c b/sys-boot/grub/files/grub2-ext4support-ext2.c
new file mode 100644
index 0000000..cc3ca13
--- /dev/null
+++ b/sys-boot/grub/files/grub2-ext4support-ext2.c
@@ -0,0 +1,142 @@
+--- trunk/grub2/fs/ext2.c	2008/07/12 15:40:50	1698
++++ trunk/grub2/fs/ext2.c	2008/07/13 01:13:12	1699
+@@ -86,6 +86,8 @@
+ #define EXT3_JOURNAL_FLAG_DELETED	4
+ #define EXT3_JOURNAL_FLAG_LAST_TAG	8
+ 
++#define EXT4_EXTENTS_FLAG		0x80000
++
+ /* The ext2 superblock.  */
+ struct grub_ext2_sblock
+ {
+@@ -226,6 +228,33 @@
+   grub_uint32_t start;
+ };
+ 
++#define EXT4_EXT_MAGIC		0xf30a
++
++struct grub_ext4_extent_header
++{
++  grub_uint16_t magic;
++  grub_uint16_t entries;
++  grub_uint16_t max;
++  grub_uint16_t depth;
++  grub_uint32_t generation;
++};
++
++struct grub_ext4_extent
++{
++  grub_uint32_t block;
++  grub_uint16_t len;
++  grub_uint16_t start_hi;
++  grub_uint32_t start;
++};
++
++struct grub_ext4_extent_idx
++{
++  grub_uint32_t block;
++  grub_uint32_t leaf;
++  grub_uint16_t leaf_hi;
++  grub_uint16_t unused;
++};
++
+ struct grub_fshelp_node
+ {
+   struct grub_ext2_data *data;
+@@ -262,6 +291,45 @@
+ 			 sizeof (struct grub_ext2_block_group), (char *) blkgrp);
+ }
+ 
++static struct grub_ext4_extent_header *
++grub_ext4_find_leaf (struct grub_ext2_data *data, char *buf,
++                     struct grub_ext4_extent_header *ext_block,
++                     grub_uint32_t fileblock)
++{
++  struct grub_ext4_extent_idx *index;
++
++  while (1)
++    {
++      int i;
++      grub_disk_addr_t block;
++
++      index = (struct grub_ext4_extent_idx *) (ext_block + 1);
++
++      if (grub_le_to_cpu16(ext_block->magic) != EXT4_EXT_MAGIC)
++        return 0;
++
++      if (ext_block->depth == 0)
++        return ext_block;
++
++      for (i = 0; i < grub_le_to_cpu16 (ext_block->entries); i++)
++        {
++          if (fileblock < grub_le_to_cpu32(index[i].block))
++            break;
++        }
++
++      if (--i < 0)
++        return 0;
++
++      block = grub_le_to_cpu16 (index[i].leaf_hi);
++      block = (block << 32) + grub_le_to_cpu32 (index[i].leaf);
++      if (grub_disk_read (data->disk,
++                          block << LOG2_EXT2_BLOCK_SIZE (data),
++                          0, EXT2_BLOCK_SIZE(data), buf))
++        return 0;
++
++      ext_block = (struct grub_ext4_extent_header *) buf;
++    }
++}
+ 
+ static grub_disk_addr_t
+ grub_ext2_read_block (grub_fshelp_node_t node, grub_disk_addr_t fileblock)
+@@ -272,6 +340,50 @@
+   unsigned int blksz = EXT2_BLOCK_SIZE (data);
+   int log2_blksz = LOG2_EXT2_BLOCK_SIZE (data);
+   
++  if (inode->flags & EXT4_EXTENTS_FLAG)
++    {
++      char buf[EXT2_BLOCK_SIZE(data)];
++      struct grub_ext4_extent_header *leaf;
++      struct grub_ext4_extent *ext;
++      int i;
++
++      leaf = grub_ext4_find_leaf (data, buf,
++                                  (struct grub_ext4_extent_header *) inode->blocks.dir_blocks,
++                                  fileblock);
++      if (! leaf)
++        {
++          grub_error (GRUB_ERR_BAD_FS, "invalid extent");
++          return -1;
++        }
++
++      ext = (struct grub_ext4_extent *) (leaf + 1);
++      for (i = 0; i < grub_le_to_cpu16 (leaf->entries); i++)
++        {
++          if (fileblock < grub_le_to_cpu32 (ext[i].block))
++            break;
++        }
++
++      if (--i >= 0)
++        {
++          fileblock -= grub_le_to_cpu32 (ext[i].block);
++          if (fileblock >= grub_le_to_cpu16 (ext[i].len))
++            return 0;
++          else
++            {
++              grub_disk_addr_t start;
++
++              start = grub_le_to_cpu16 (ext[i].start_hi);
++              start = (start << 32) + grub_le_to_cpu32 (ext[i].start);
++
++              return fileblock + start;
++            }
++        }
++      else
++        {
++          grub_error (GRUB_ERR_BAD_FS, "something wrong with extent");
++          return -1;
++        }
++    }
+   /* Direct blocks.  */
+   if (fileblock < INDIRECT_BLOCKS)
+     blknr = grub_le_to_cpu32 (inode->blocks.dir_blocks[fileblock]);