grub/patches/grub-0.97-ext4-2.patch

diff -Naur grub-0.97/stage2/fsys_ext2fs.c grub-0.97-magellan/stage2/fsys_ext2fs.c
--- grub-0.97/stage2/fsys_ext2fs.c	2004-08-08 20:19:18.000000000 +0200
+++ grub-0.97-magellan/stage2/fsys_ext2fs.c	2009-10-16 17:26:03.000000000 +0200
@@ -41,6 +41,7 @@
 typedef unsigned short __u16;
 typedef __signed__ int __s32;
 typedef unsigned int __u32;
+typedef unsigned long long __u64;
 
 /*
  * Constants relative to the data blocks, from ext2_fs.h
@@ -51,7 +52,7 @@
 #define EXT2_TIND_BLOCK                 (EXT2_DIND_BLOCK + 1)
 #define EXT2_N_BLOCKS                   (EXT2_TIND_BLOCK + 1)
 
-/* include/linux/ext2_fs.h */
+/* lib/ext2fs/ext2_fs.h from e2fsprogs */
 struct ext2_super_block
   {
     __u32 s_inodes_count;	/* Inodes count */
@@ -61,9 +62,9 @@
     __u32 s_free_inodes_count;	/* Free inodes count */
     __u32 s_first_data_block;	/* First Data Block */
     __u32 s_log_block_size;	/* Block size */
-    __s32 s_log_frag_size;	/* Fragment size */
+    __s32 s_obso_log_frag_size;	/* Obsoleted Fragment size */
     __u32 s_blocks_per_group;	/* # Blocks per group */
-    __u32 s_frags_per_group;	/* # Fragments per group */
+    __u32 s_obso_frags_per_group;	/* Obsoleted Fragments per group */
     __u32 s_inodes_per_group;	/* # Inodes per group */
     __u32 s_mtime;		/* Mount time */
     __u32 s_wtime;		/* Write time */
@@ -72,17 +73,32 @@
     __u16 s_magic;		/* Magic signature */
     __u16 s_state;		/* File system state */
     __u16 s_errors;		/* Behaviour when detecting errors */
-    __u16 s_pad;
+    __u16 s_minor_rev_level;	/* minor revision level */
+    __u16 s_desc_size;		/* size of group descriptor */
     __u32 s_lastcheck;		/* time of last check */
     __u32 s_checkinterval;	/* max. time between checks */
     __u32 s_creator_os;		/* OS */
     __u32 s_rev_level;		/* Revision level */
     __u16 s_def_resuid;		/* Default uid for reserved blocks */
     __u16 s_def_resgid;		/* Default gid for reserved blocks */
-    __u32 s_reserved[235];	/* Padding to the end of the block */
-  };
+    /* 64bit desc support valid if EXT4_FEATURE_INCOMPAT_64BIT */
+    __u32 s_blocks_count_hi;	/* Blocks count */
+    __u32 s_r_blocks_count_hi;	/* Reserved blocks count */
+    __u32 s_free_blocks_count_hi; /* Free blocks count */
+    __u16 s_min_extra_isize;	/* All inodes have at least # bytes */
+    __u16 s_max_extra_isize;	/* New inodes should reverve # bytes */
+    __u32 s_flags;		/* Miscellaneous flags */
+    __u16 s_raid_stride;	/* Raid stride */
+    __u16 s_mmp_interval;	/* # seconds to wait MMP checking */
+    __u64 s_mmp_block;		/* Block for multi-mount protection */
+    __u32 s_raid_stripe_width;	/* Blocks on all data disks (N*stride)*/
+    __u8  s_log_groups_per_flex;/* FLEX_BG group size*/
+    __u8  s_reserved_char_pad;
+    __u16 s_reserved_pad;
+    __u32 s_reserved[162];	/* Padding to the end of the block */
+};
 
-struct ext2_group_desc
+struct ext4_group_desc
   {
     __u32 bg_block_bitmap;	/* Blocks bitmap block */
     __u32 bg_inode_bitmap;	/* Inodes bitmap block */
@@ -90,8 +106,18 @@
     __u16 bg_free_blocks_count;	/* Free blocks count */
     __u16 bg_free_inodes_count;	/* Free inodes count */
     __u16 bg_used_dirs_count;	/* Directories count */
-    __u16 bg_pad;
-    __u32 bg_reserved[3];
+    __u16 bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
+    __u32 bg_reserved[2];		/* Likely block/inode bitmap checksum */
+    __u16 bg_itable_unused;	/* Unused inodes count */
+    __u16 bg_checksum;		/* crc16(sb_uuid+group+desc) */
+    __u32 bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
+    __u32 bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
+    __u32 bg_inode_table_hi;	/* Inodes table block MSB */
+    __u16 bg_free_blocks_count_hi;/* Free blocks count MSB */
+    __u16 bg_free_inodes_count_hi;/* Free inodes count MSB */
+    __u16 bg_used_dirs_count_hi;	/* Directories count MSB */
+    __u16 bg_itable_unused_hi;	/* Unused inodes count MSB */
+    __u32 bg_reserved2[3];
   };
 
 struct ext2_inode
@@ -129,22 +155,22 @@
     __u32 i_block[EXT2_N_BLOCKS];	/* 40: Pointers to blocks */
     __u32 i_version;		/* File version (for NFS) */
     __u32 i_file_acl;		/* File ACL */
-    __u32 i_dir_acl;		/* Directory ACL */
-    __u32 i_faddr;		/* Fragment address */
+    __u32 i_size_high;
+    __u32 i_obso_faddr;		/* Obsoleted fragment address */
     union
       {
 	struct
 	  {
-	    __u8 l_i_frag;	/* Fragment number */
-	    __u8 l_i_fsize;	/* Fragment size */
-	    __u16 i_pad1;
-	    __u32 l_i_reserved2[2];
+		__u16	l_i_blocks_high; /* were l_i_reserved1 */
+		__u16	l_i_file_acl_high;
+		__u16	l_i_uid_high;	/* these 2 fields */
+		__u16	l_i_gid_high;	/* were reserved2[0] */
+		__u32	l_i_reserved2;
 	  }
 	linux2;
 	struct
 	  {
-	    __u8 h_i_frag;	/* Fragment number */
-	    __u8 h_i_fsize;	/* Fragment size */
+		__u16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
 	    __u16 h_i_mode_high;
 	    __u16 h_i_uid_high;
 	    __u16 h_i_gid_high;
@@ -153,16 +179,36 @@
 	hurd2;
 	struct
 	  {
-	    __u8 m_i_frag;	/* Fragment number */
-	    __u8 m_i_fsize;	/* Fragment size */
-	    __u16 m_pad1;
+		__u16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
+		__u16	m_i_file_acl_high;
 	    __u32 m_i_reserved2[2];
 	  }
 	masix2;
       }
     osd2;			/* OS dependent 2 */
+	__u16	i_extra_isize;
+	__u16	i_pad1;
+	__u32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
+	__u32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
+	__u32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
+	__u32  i_crtime;       /* File Creation time */
+	__u32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
+	__u32  i_version_hi;	/* high 32 bits for 64-bit version */
   };
 
+#define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
+#define EXT4_FEATURE_INCOMPAT_64BIT			0x0080 /* grub not supported*/
+#define EXT4_FEATURE_INCOMPAT_MMP           0x0100
+#define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
+
+#define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)			\
+	( sb->s_feature_incompat & mask )
+
+#define EXT4_EXTENTS_FL		0x00080000 /* Inode uses extents */
+#define EXT4_HUGE_FILE_FL	0x00040000 /* Set to each huge file */
+
+#define EXT4_MIN_DESC_SIZE			32
+
 /* linux/limits.h */
 #define NAME_MAX         255	/* # chars in a file name */
 
@@ -180,6 +226,56 @@
     char name[EXT2_NAME_LEN];	/* File name */
   };
 
+/* linux/ext4_fs_extents.h */
+/* This is the extent on-disk structure.
+ * It's used at the bottom of the tree.
+ */
+struct ext4_extent
+  {
+	__u32  ee_block;   /* first logical block extent covers */
+	__u16  ee_len;     /* number of blocks covered by extent */
+	__u16  ee_start_hi;    /* high 16 bits of physical block */
+	__u32  ee_start_lo;    /* low 32 bits of physical block */
+  };
+
+/*
+ * This is index on-disk structure.
+ * It's used at all the levels except the bottom.
+ */
+struct ext4_extent_idx
+  {
+    __u32  ei_block;   /* index covers logical blocks from 'block' */
+    __u32  ei_leaf_lo; /* pointer to the physical block of the next *
+	                     * level. leaf or next index could be there */
+    __u16  ei_leaf_hi; /* high 16 bits of physical block */
+    __u16  ei_unused;
+  };
+
+/*
+ * Each block (leaves and indexes), even inode-stored has header.
+ */
+struct ext4_extent_header
+  {
+    __u16  eh_magic;   /* probably will support different formats */
+    __u16  eh_entries; /* number of valid entries */
+    __u16  eh_max;     /* capacity of store in entries */
+    __u16  eh_depth;   /* has tree real underlying blocks? */
+    __u32  eh_generation;  /* generation of the tree */
+  };
+
+#define EXT4_EXT_MAGIC      (0xf30a)
+#define EXT_FIRST_EXTENT(__hdr__) \
+    ((struct ext4_extent *) (((char *) (__hdr__)) +     \
+                 sizeof(struct ext4_extent_header)))
+#define EXT_FIRST_INDEX(__hdr__) \
+    ((struct ext4_extent_idx *) (((char *) (__hdr__)) + \
+                 sizeof(struct ext4_extent_header)))
+#define EXT_LAST_EXTENT(__hdr__) \
+    (EXT_FIRST_EXTENT((__hdr__)) + (__u16)((__hdr__)->eh_entries) - 1)
+#define EXT_LAST_INDEX(__hdr__) \
+    (EXT_FIRST_INDEX((__hdr__)) + (__u16)((__hdr__)->eh_entries) - 1)
+
+
 /* linux/ext2fs.h */
 /*
  * EXT2_DIR_PAD defines the directory entries boundaries
@@ -223,8 +319,17 @@
 /* kind of from ext2/super.c */
 #define EXT2_BLOCK_SIZE(s)	(1 << EXT2_BLOCK_SIZE_BITS(s))
 /* linux/ext2fs.h */
+/* sizeof(struct ext2_group_desc) is changed in ext4
+ * in kernel code, ext2/3 uses sizeof(struct ext2_group_desc) to calculate
+ * number of desc per block, while ext4 uses superblock->s_desc_size in stead
+ * superblock->s_desc_size is not available in ext2/3
+ * */
+#define EXT2_DESC_SIZE(s) \
+	(EXT4_HAS_INCOMPAT_FEATURE(s,EXT4_FEATURE_INCOMPAT_64BIT)? \
+	s->s_desc_size : EXT4_MIN_DESC_SIZE)
 #define EXT2_DESC_PER_BLOCK(s) \
-     (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
+	(EXT2_BLOCK_SIZE(s) / EXT2_DESC_SIZE(s))
+
 /* linux/stat.h */
 #define S_IFMT  00170000
 #define S_IFLNK  0120000
@@ -386,6 +491,122 @@
     [logical_block & (EXT2_ADDR_PER_BLOCK (SUPERBLOCK) - 1)];
 }
 
+/* extent binary search index
+ * find closest index in the current level extent tree
+ * kind of from ext4_ext_binsearch_idx in ext4/extents.c
+ */
+static struct ext4_extent_idx*
+ext4_ext_binsearch_idx(struct ext4_extent_header* eh, int logical_block)
+{
+  struct ext4_extent_idx *r, *l, *m;
+  l = EXT_FIRST_INDEX(eh) + 1;
+  r = EXT_LAST_INDEX(eh);
+  while (l <= r)
+    {
+	  m = l + (r - l) / 2;
+	  if (logical_block < m->ei_block)
+		  r = m - 1;
+	  else
+		  l = m + 1;
+	}
+  return (struct ext4_extent_idx*)(l - 1);
+}
+
+/* extent binary search
+ * find closest extent in the leaf level
+ * kind of from ext4_ext_binsearch in ext4/extents.c
+ */
+static struct ext4_extent*
+ext4_ext_binsearch(struct ext4_extent_header* eh, int logical_block)
+{
+  struct ext4_extent *r, *l, *m;
+  l = EXT_FIRST_EXTENT(eh) + 1;
+  r = EXT_LAST_EXTENT(eh);
+  while (l <= r)
+    {
+	  m = l + (r - l) / 2;
+	  if (logical_block < m->ee_block)
+		  r = m - 1;
+	  else
+		  l = m + 1;
+	}
+  return (struct ext4_extent*)(l - 1);
+}
+
+/* Maps extents enabled logical block into physical block via an inode.
+ * EXT4_HUGE_FILE_FL should be checked before calling this.
+ */
+static int
+ext4fs_block_map (int logical_block)
+{
+  struct ext4_extent_header *eh;
+  struct ext4_extent *ex, *extent;
+  struct ext4_extent_idx *ei, *index;
+  int depth;
+  int i;
+
+#ifdef E2DEBUG
+  unsigned char *i;
+  for (i = (unsigned char *) INODE;
+       i < ((unsigned char *) INODE + sizeof (struct ext2_inode));
+       i++)
+    {
+      printf ("%c", "0123456789abcdef"[*i >> 4]);
+      printf ("%c", "0123456789abcdef"[*i % 16]);
+      if (!((i + 1 - (unsigned char *) INODE) % 16))
+	{
+	  printf ("\n");
+	}
+      else
+	{
+	  printf (" ");
+	}
+    }
+  printf ("logical block %d\n", logical_block);
+#endif /* E2DEBUG */
+  eh = (struct ext4_extent_header*)INODE->i_block;
+  if (eh->eh_magic != EXT4_EXT_MAGIC)
+  {
+          errnum = ERR_FSYS_CORRUPT;
+          return -1;
+  }
+  while((depth = eh->eh_depth) != 0)
+  	{ /* extent index */
+	  if (eh->eh_magic != EXT4_EXT_MAGIC)
+	  {
+	          errnum = ERR_FSYS_CORRUPT;
+		  return -1;
+	  }
+	  ei = ext4_ext_binsearch_idx(eh, logical_block);
+	  if (ei->ei_leaf_hi)
+	{/* 64bit physical block number not supported */
+	  errnum = ERR_FILELENGTH;
+	  return -1;
+	}
+	  if (!ext2_rdfsb(ei->ei_leaf_lo, DATABLOCK1))
+	{
+	  errnum = ERR_FSYS_CORRUPT;
+	  return -1;
+	}
+	  eh = (struct ext4_extent_header*)DATABLOCK1;
+  	}
+
+  /* depth==0, we come to the leaf */
+  ex = ext4_ext_binsearch(eh, logical_block);
+  if (ex->ee_start_hi)
+	{/* 64bit physical block number not supported */
+	  errnum = ERR_FILELENGTH;
+	  return -1;
+	}
+  if ((ex->ee_block + ex->ee_len) < logical_block)
+	{
+	  errnum = ERR_FSYS_CORRUPT;
+	  return -1;
+	}
+  return ex->ee_start_lo + logical_block - ex->ee_block;
+
+}
+
 /* preconditions: all preconds of ext2fs_block_map */
 int
 ext2fs_read (char *buf, int len)
@@ -420,6 +641,11 @@
       /* find the (logical) block component of our location */
       logical_block = filepos >> EXT2_BLOCK_SIZE_BITS (SUPERBLOCK);
       offset = filepos & (EXT2_BLOCK_SIZE (SUPERBLOCK) - 1);
+      /* map extents enabled logical block number to physical fs on-disk block number */
+      if (EXT4_HAS_INCOMPAT_FEATURE(SUPERBLOCK,EXT4_FEATURE_INCOMPAT_EXTENTS)
+                    && INODE->i_flags & EXT4_EXTENTS_FL)
+          map = ext4fs_block_map (logical_block);
+      else
       map = ext2fs_block_map (logical_block);
 #ifdef E2DEBUG
       printf ("map=%d\n", map);
@@ -504,7 +730,7 @@
   int desc;			/* index within that group */
   int ino_blk;			/* fs pointer of the inode's information */
   int str_chk = 0;		/* used to hold the results of a string compare */
-  struct ext2_group_desc *gdp;
+  struct ext4_group_desc *ext4_gdp;
   struct ext2_inode *raw_inode;	/* inode info corresponding to current_ino */
 
   char linkbuf[PATH_MAX];	/* buffer for following symbolic links */
@@ -550,8 +776,15 @@
 	{
 	  return 0;
 	}
-      gdp = GROUP_DESC;
-      ino_blk = gdp[desc].bg_inode_table +
+	  ext4_gdp = (struct ext4_group_desc *)( (__u8*)GROUP_DESC +
+			  		desc * EXT2_DESC_SIZE(SUPERBLOCK));
+	  if (EXT4_HAS_INCOMPAT_FEATURE(SUPERBLOCK, EXT4_FEATURE_INCOMPAT_64BIT)
+		&& (! ext4_gdp->bg_inode_table_hi))
+	{/* 64bit itable not supported */
+	  errnum = ERR_FILELENGTH;
+	  return -1;
+	}
+      ino_blk = ext4_gdp->bg_inode_table +
 	(((current_ino - 1) % (SUPERBLOCK->s_inodes_per_group))
 	 >> log2 (EXT2_BLOCK_SIZE (SUPERBLOCK) / sizeof (struct ext2_inode)));
 #ifdef E2DEBUG
@@ -629,7 +862,10 @@
 	    }
 	  linkbuf[filemax + len] = '\0';
 
-	  /* Read the symlink data. */
+	  /* Read the symlink data.
+	   * Slow symlink is extents enabled
+	   * But since grub_read invokes ext2fs_read, nothing to change here
+	   */
 	  if (! ext2_is_fast_symlink ())
 	    {
 	      /* Read the necessary blocks, and reset the file pointer. */
@@ -640,7 +876,9 @@
 	    }
 	  else
 	    {
-	      /* Copy the data directly from the inode. */
+	      /* Copy the data directly from the inode.
+	       * Fast symlink is not extents enabled
+	       */
 	      len = filemax;
 	      memmove (linkbuf, (char *) INODE->i_block, len);
 	    }
@@ -674,7 +912,13 @@
 	      errnum = ERR_BAD_FILETYPE;
 	      return 0;
 	    }
-
+	  /* if file is too large, just stop and report an error*/
+	  if ( (INODE->i_flags & EXT4_HUGE_FILE_FL) && !(INODE->i_size_high))
+	    {
+		  /* file too large, stop reading */
+		  errnum = ERR_FILELENGTH;
+		  return 0;
+	    }
 	  filemax = (INODE->i_size);
 	  return 1;
 	}
@@ -728,17 +972,28 @@
 	    }
 
 	  /* else, find the (logical) block component of our location */
+	  /* ext4 logical block number the same as ext2/3 */
 	  blk = loc >> EXT2_BLOCK_SIZE_BITS (SUPERBLOCK);
 
 	  /* we know which logical block of the directory entry we are looking
 	     for, now we have to translate that to the physical (fs) block on
 	     the disk */
+	  /* map extents enabled logical block number to physical fs on-disk block number */
+	  if (EXT4_HAS_INCOMPAT_FEATURE(SUPERBLOCK,EXT4_FEATURE_INCOMPAT_EXTENTS)
+                        && INODE->i_flags & EXT4_EXTENTS_FL)
+              map = ext4fs_block_map (blk);
+	  else
 	  map = ext2fs_block_map (blk);
 #ifdef E2DEBUG
 	  printf ("fs block=%d\n", map);
 #endif /* E2DEBUG */
 	  mapblock2 = -1;
-	  if ((map < 0) || !ext2_rdfsb (map, DATABLOCK2))
+	  if (map < 0)
+	  {
+	      *rest = ch;
+	      return 0;
+	  }
+          if (!ext2_rdfsb (map, DATABLOCK2))
 	    {
 	      errnum = ERR_FSYS_CORRUPT;
 	      *rest = ch;
1	diff -Naur grub-0.97/stage2/fsys_ext2fs.c grub-0.97-magellan/stage2/fsys_ext2fs.c
2	--- grub-0.97/stage2/fsys_ext2fs.c 2004-08-08 20:19:18.000000000 +0200
3	+++ grub-0.97-magellan/stage2/fsys_ext2fs.c 2009-10-16 17:26:03.000000000 +0200
4	@@ -41,6 +41,7 @@
5	typedef unsigned short __u16;
6	typedef __signed__ int __s32;
7	typedef unsigned int __u32;
8	+typedef unsigned long long __u64;
9
10	/*
11	* Constants relative to the data blocks, from ext2_fs.h
12	@@ -51,7 +52,7 @@
13	#define EXT2_TIND_BLOCK (EXT2_DIND_BLOCK + 1)
14	#define EXT2_N_BLOCKS (EXT2_TIND_BLOCK + 1)
15
16	-/* include/linux/ext2_fs.h */
17	+/* lib/ext2fs/ext2_fs.h from e2fsprogs */
18	struct ext2_super_block
19	{
20	__u32 s_inodes_count; /* Inodes count */
21	@@ -61,9 +62,9 @@
22	__u32 s_free_inodes_count; /* Free inodes count */
23	__u32 s_first_data_block; /* First Data Block */
24	__u32 s_log_block_size; /* Block size */
25	- __s32 s_log_frag_size; /* Fragment size */
26	+ __s32 s_obso_log_frag_size; /* Obsoleted Fragment size */
27	__u32 s_blocks_per_group; /* # Blocks per group */
28	- __u32 s_frags_per_group; /* # Fragments per group */
29	+ __u32 s_obso_frags_per_group; /* Obsoleted Fragments per group */
30	__u32 s_inodes_per_group; /* # Inodes per group */
31	__u32 s_mtime; /* Mount time */
32	__u32 s_wtime; /* Write time */
33	@@ -72,17 +73,32 @@
34	__u16 s_magic; /* Magic signature */
35	__u16 s_state; /* File system state */
36	__u16 s_errors; /* Behaviour when detecting errors */
37	- __u16 s_pad;
38	+ __u16 s_minor_rev_level; /* minor revision level */
39	+ __u16 s_desc_size; /* size of group descriptor */
40	__u32 s_lastcheck; /* time of last check */
41	__u32 s_checkinterval; /* max. time between checks */
42	__u32 s_creator_os; /* OS */
43	__u32 s_rev_level; /* Revision level */
44	__u16 s_def_resuid; /* Default uid for reserved blocks */
45	__u16 s_def_resgid; /* Default gid for reserved blocks */
46	- __u32 s_reserved[235]; /* Padding to the end of the block */
47	- };
48	+ /* 64bit desc support valid if EXT4_FEATURE_INCOMPAT_64BIT */
49	+ __u32 s_blocks_count_hi; /* Blocks count */
50	+ __u32 s_r_blocks_count_hi; /* Reserved blocks count */
51	+ __u32 s_free_blocks_count_hi; /* Free blocks count */
52	+ __u16 s_min_extra_isize; /* All inodes have at least # bytes */
53	+ __u16 s_max_extra_isize; /* New inodes should reverve # bytes */
54	+ __u32 s_flags; /* Miscellaneous flags */
55	+ __u16 s_raid_stride; /* Raid stride */
56	+ __u16 s_mmp_interval; /* # seconds to wait MMP checking */
57	+ __u64 s_mmp_block; /* Block for multi-mount protection */
58	+ __u32 s_raid_stripe_width; /* Blocks on all data disks (Nstride)/
59	+ __u8 s_log_groups_per_flex;/* FLEX_BG group size*/
60	+ __u8 s_reserved_char_pad;
61	+ __u16 s_reserved_pad;
62	+ __u32 s_reserved[162]; /* Padding to the end of the block */
63	+};
64
65	-struct ext2_group_desc
66	+struct ext4_group_desc
67	{
68	__u32 bg_block_bitmap; /* Blocks bitmap block */
69	__u32 bg_inode_bitmap; /* Inodes bitmap block */
70	@@ -90,8 +106,18 @@
71	__u16 bg_free_blocks_count; /* Free blocks count */
72	__u16 bg_free_inodes_count; /* Free inodes count */
73	__u16 bg_used_dirs_count; /* Directories count */
74	- __u16 bg_pad;
75	- __u32 bg_reserved[3];
76	+ __u16 bg_flags; /* EXT4_BG_flags (INODE_UNINIT, etc) */
77	+ __u32 bg_reserved[2]; /* Likely block/inode bitmap checksum */
78	+ __u16 bg_itable_unused; /* Unused inodes count */
79	+ __u16 bg_checksum; /* crc16(sb_uuid+group+desc) */
80	+ __u32 bg_block_bitmap_hi; /* Blocks bitmap block MSB */
81	+ __u32 bg_inode_bitmap_hi; /* Inodes bitmap block MSB */
82	+ __u32 bg_inode_table_hi; /* Inodes table block MSB */
83	+ __u16 bg_free_blocks_count_hi;/* Free blocks count MSB */
84	+ __u16 bg_free_inodes_count_hi;/* Free inodes count MSB */
85	+ __u16 bg_used_dirs_count_hi; /* Directories count MSB */
86	+ __u16 bg_itable_unused_hi; /* Unused inodes count MSB */
87	+ __u32 bg_reserved2[3];
88	};
89
90	struct ext2_inode
91	@@ -129,22 +155,22 @@
92	__u32 i_block[EXT2_N_BLOCKS]; /* 40: Pointers to blocks */
93	__u32 i_version; /* File version (for NFS) */
94	__u32 i_file_acl; /* File ACL */
95	- __u32 i_dir_acl; /* Directory ACL */
96	- __u32 i_faddr; /* Fragment address */
97	+ __u32 i_size_high;
98	+ __u32 i_obso_faddr; /* Obsoleted fragment address */
99	union
100	{
101	struct
102	{
103	- __u8 l_i_frag; /* Fragment number */
104	- __u8 l_i_fsize; /* Fragment size */
105	- __u16 i_pad1;
106	- __u32 l_i_reserved2[2];
107	+ __u16 l_i_blocks_high; /* were l_i_reserved1 */
108	+ __u16 l_i_file_acl_high;
109	+ __u16 l_i_uid_high; /* these 2 fields */
110	+ __u16 l_i_gid_high; /* were reserved2[0] */
111	+ __u32 l_i_reserved2;
112	}
113	linux2;
114	struct
115	{
116	- __u8 h_i_frag; /* Fragment number */
117	- __u8 h_i_fsize; /* Fragment size */
118	+ __u16 h_i_reserved1; /* Obsoleted fragment number/size which are removed in ext4 */
119	__u16 h_i_mode_high;
120	__u16 h_i_uid_high;
121	__u16 h_i_gid_high;
122	@@ -153,16 +179,36 @@
123	hurd2;
124	struct
125	{
126	- __u8 m_i_frag; /* Fragment number */
127	- __u8 m_i_fsize; /* Fragment size */
128	- __u16 m_pad1;
129	+ __u16 h_i_reserved1; /* Obsoleted fragment number/size which are removed in ext4 */
130	+ __u16 m_i_file_acl_high;
131	__u32 m_i_reserved2[2];
132	}
133	masix2;
134	}
135	osd2; /* OS dependent 2 */
136	+ __u16 i_extra_isize;
137	+ __u16 i_pad1;
138	+ __u32 i_ctime_extra; /* extra Change time (nsec << 2 \| epoch) */
139	+ __u32 i_mtime_extra; /* extra Modification time(nsec << 2 \| epoch) */
140	+ __u32 i_atime_extra; /* extra Access time (nsec << 2 \| epoch) */
141	+ __u32 i_crtime; /* File Creation time */
142	+ __u32 i_crtime_extra; /* extra FileCreationtime (nsec << 2 \| epoch) */
143	+ __u32 i_version_hi; /* high 32 bits for 64-bit version */
144	};
145
146	+#define EXT4_FEATURE_INCOMPAT_EXTENTS 0x0040 /* extents support */
147	+#define EXT4_FEATURE_INCOMPAT_64BIT 0x0080 /* grub not supported*/
148	+#define EXT4_FEATURE_INCOMPAT_MMP 0x0100
149	+#define EXT4_FEATURE_INCOMPAT_FLEX_BG 0x0200
150	+
151	+#define EXT4_HAS_INCOMPAT_FEATURE(sb,mask) \
152	+ ( sb->s_feature_incompat & mask )
153	+
154	+#define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */
155	+#define EXT4_HUGE_FILE_FL 0x00040000 /* Set to each huge file */
156	+
157	+#define EXT4_MIN_DESC_SIZE 32
158	+
159	/* linux/limits.h */
160	#define NAME_MAX 255 /* # chars in a file name */
161
162	@@ -180,6 +226,56 @@
163	char name[EXT2_NAME_LEN]; /* File name */
164	};
165
166	+/* linux/ext4_fs_extents.h */
167	+/* This is the extent on-disk structure.
168	+ * It's used at the bottom of the tree.
169	+ */
170	+struct ext4_extent
171	+ {
172	+ __u32 ee_block; /* first logical block extent covers */
173	+ __u16 ee_len; /* number of blocks covered by extent */
174	+ __u16 ee_start_hi; /* high 16 bits of physical block */
175	+ __u32 ee_start_lo; /* low 32 bits of physical block */
176	+ };
177	+
178	+/*
179	+ * This is index on-disk structure.
180	+ * It's used at all the levels except the bottom.
181	+ */
182	+struct ext4_extent_idx
183	+ {
184	+ __u32 ei_block; /* index covers logical blocks from 'block' */
185	+ __u32 ei_leaf_lo; /* pointer to the physical block of the next *
186	+ * level. leaf or next index could be there */
187	+ __u16 ei_leaf_hi; /* high 16 bits of physical block */
188	+ __u16 ei_unused;
189	+ };
190	+
191	+/*
192	+ * Each block (leaves and indexes), even inode-stored has header.
193	+ */
194	+struct ext4_extent_header
195	+ {
196	+ __u16 eh_magic; /* probably will support different formats */
197	+ __u16 eh_entries; /* number of valid entries */
198	+ __u16 eh_max; /* capacity of store in entries */
199	+ __u16 eh_depth; /* has tree real underlying blocks? */
200	+ __u32 eh_generation; /* generation of the tree */
201	+ };
202	+
203	+#define EXT4_EXT_MAGIC (0xf30a)
204	+#define EXT_FIRST_EXTENT(__hdr__) \
205	+ ((struct ext4_extent ) (((char ) (__hdr__)) + \
206	+ sizeof(struct ext4_extent_header)))
207	+#define EXT_FIRST_INDEX(__hdr__) \
208	+ ((struct ext4_extent_idx ) (((char ) (__hdr__)) + \
209	+ sizeof(struct ext4_extent_header)))
210	+#define EXT_LAST_EXTENT(__hdr__) \
211	+ (EXT_FIRST_EXTENT((__hdr__)) + (__u16)((__hdr__)->eh_entries) - 1)
212	+#define EXT_LAST_INDEX(__hdr__) \
213	+ (EXT_FIRST_INDEX((__hdr__)) + (__u16)((__hdr__)->eh_entries) - 1)
214	+
215	+
216	/* linux/ext2fs.h */
217	/*
218	* EXT2_DIR_PAD defines the directory entries boundaries
219	@@ -223,8 +319,17 @@
220	/* kind of from ext2/super.c */
221	#define EXT2_BLOCK_SIZE(s) (1 << EXT2_BLOCK_SIZE_BITS(s))
222	/* linux/ext2fs.h */
223	+/* sizeof(struct ext2_group_desc) is changed in ext4
224	+ * in kernel code, ext2/3 uses sizeof(struct ext2_group_desc) to calculate
225	+ * number of desc per block, while ext4 uses superblock->s_desc_size in stead
226	+ * superblock->s_desc_size is not available in ext2/3
227	+ * */
228	+#define EXT2_DESC_SIZE(s) \
229	+ (EXT4_HAS_INCOMPAT_FEATURE(s,EXT4_FEATURE_INCOMPAT_64BIT)? \
230	+ s->s_desc_size : EXT4_MIN_DESC_SIZE)
231	#define EXT2_DESC_PER_BLOCK(s) \
232	- (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
233	+ (EXT2_BLOCK_SIZE(s) / EXT2_DESC_SIZE(s))
234	+
235	/* linux/stat.h */
236	#define S_IFMT 00170000
237	#define S_IFLNK 0120000
238	@@ -386,6 +491,122 @@
239	[logical_block & (EXT2_ADDR_PER_BLOCK (SUPERBLOCK) - 1)];
240	}
241
242	+/* extent binary search index
243	+ * find closest index in the current level extent tree
244	+ * kind of from ext4_ext_binsearch_idx in ext4/extents.c
245	+ */
246	+static struct ext4_extent_idx*
247	+ext4_ext_binsearch_idx(struct ext4_extent_header* eh, int logical_block)
248	+{
249	+ struct ext4_extent_idx r, l, *m;
250	+ l = EXT_FIRST_INDEX(eh) + 1;
251	+ r = EXT_LAST_INDEX(eh);
252	+ while (l <= r)
253	+ {
254	+ m = l + (r - l) / 2;
255	+ if (logical_block < m->ei_block)
256	+ r = m - 1;
257	+ else
258	+ l = m + 1;
259	+ }
260	+ return (struct ext4_extent_idx*)(l - 1);
261	+}
262	+
263	+/* extent binary search
264	+ * find closest extent in the leaf level
265	+ * kind of from ext4_ext_binsearch in ext4/extents.c
266	+ */
267	+static struct ext4_extent*
268	+ext4_ext_binsearch(struct ext4_extent_header* eh, int logical_block)
269	+{
270	+ struct ext4_extent r, l, *m;
271	+ l = EXT_FIRST_EXTENT(eh) + 1;
272	+ r = EXT_LAST_EXTENT(eh);
273	+ while (l <= r)
274	+ {
275	+ m = l + (r - l) / 2;
276	+ if (logical_block < m->ee_block)
277	+ r = m - 1;
278	+ else
279	+ l = m + 1;
280	+ }
281	+ return (struct ext4_extent*)(l - 1);
282	+}
283	+
284	+/* Maps extents enabled logical block into physical block via an inode.
285	+ * EXT4_HUGE_FILE_FL should be checked before calling this.
286	+ */
287	+static int
288	+ext4fs_block_map (int logical_block)
289	+{
290	+ struct ext4_extent_header *eh;
291	+ struct ext4_extent ex, extent;
292	+ struct ext4_extent_idx ei, index;
293	+ int depth;
294	+ int i;
295	+
296	+#ifdef E2DEBUG
297	+ unsigned char *i;
298	+ for (i = (unsigned char *) INODE;
299	+ i < ((unsigned char *) INODE + sizeof (struct ext2_inode));
300	+ i++)
301	+ {
302	+ printf ("%c", "0123456789abcdef"[*i >> 4]);
303	+ printf ("%c", "0123456789abcdef"[*i % 16]);
304	+ if (!((i + 1 - (unsigned char *) INODE) % 16))
305	+ {
306	+ printf ("\n");
307	+ }
308	+ else
309	+ {
310	+ printf (" ");
311	+ }
312	+ }
313	+ printf ("logical block %d\n", logical_block);
314	+#endif /* E2DEBUG */
315	+ eh = (struct ext4_extent_header*)INODE->i_block;
316	+ if (eh->eh_magic != EXT4_EXT_MAGIC)
317	+ {
318	+ errnum = ERR_FSYS_CORRUPT;
319	+ return -1;
320	+ }
321	+ while((depth = eh->eh_depth) != 0)
322	+ { /* extent index */
323	+ if (eh->eh_magic != EXT4_EXT_MAGIC)
324	+ {
325	+ errnum = ERR_FSYS_CORRUPT;
326	+ return -1;
327	+ }
328	+ ei = ext4_ext_binsearch_idx(eh, logical_block);
329	+ if (ei->ei_leaf_hi)
330	+ {/* 64bit physical block number not supported */
331	+ errnum = ERR_FILELENGTH;
332	+ return -1;
333	+ }
334	+ if (!ext2_rdfsb(ei->ei_leaf_lo, DATABLOCK1))
335	+ {
336	+ errnum = ERR_FSYS_CORRUPT;
337	+ return -1;
338	+ }
339	+ eh = (struct ext4_extent_header*)DATABLOCK1;
340	+ }
341	+
342	+ /* depth==0, we come to the leaf */
343	+ ex = ext4_ext_binsearch(eh, logical_block);
344	+ if (ex->ee_start_hi)
345	+ {/* 64bit physical block number not supported */
346	+ errnum = ERR_FILELENGTH;
347	+ return -1;
348	+ }
349	+ if ((ex->ee_block + ex->ee_len) < logical_block)
350	+ {
351	+ errnum = ERR_FSYS_CORRUPT;
352	+ return -1;
353	+ }
354	+ return ex->ee_start_lo + logical_block - ex->ee_block;
355	+
356	+}
357	+
358	/* preconditions: all preconds of ext2fs_block_map */
359	int
360	ext2fs_read (char *buf, int len)
361	@@ -420,6 +641,11 @@
362	/* find the (logical) block component of our location */
363	logical_block = filepos >> EXT2_BLOCK_SIZE_BITS (SUPERBLOCK);
364	offset = filepos & (EXT2_BLOCK_SIZE (SUPERBLOCK) - 1);
365	+ /* map extents enabled logical block number to physical fs on-disk block number */
366	+ if (EXT4_HAS_INCOMPAT_FEATURE(SUPERBLOCK,EXT4_FEATURE_INCOMPAT_EXTENTS)
367	+ && INODE->i_flags & EXT4_EXTENTS_FL)
368	+ map = ext4fs_block_map (logical_block);
369	+ else
370	map = ext2fs_block_map (logical_block);
371	#ifdef E2DEBUG
372	printf ("map=%d\n", map);
373	@@ -504,7 +730,7 @@
374	int desc; /* index within that group */
375	int ino_blk; /* fs pointer of the inode's information */
376	int str_chk = 0; /* used to hold the results of a string compare */
377	- struct ext2_group_desc *gdp;
378	+ struct ext4_group_desc *ext4_gdp;
379	struct ext2_inode raw_inode; / inode info corresponding to current_ino */
380
381	char linkbuf[PATH_MAX]; /* buffer for following symbolic links */
382	@@ -550,8 +776,15 @@
383	{
384	return 0;
385	}
386	- gdp = GROUP_DESC;
387	- ino_blk = gdp[desc].bg_inode_table +
388	+ ext4_gdp = (struct ext4_group_desc )( (__u8)GROUP_DESC +
389	+ desc * EXT2_DESC_SIZE(SUPERBLOCK));
390	+ if (EXT4_HAS_INCOMPAT_FEATURE(SUPERBLOCK, EXT4_FEATURE_INCOMPAT_64BIT)
391	+ && (! ext4_gdp->bg_inode_table_hi))
392	+ {/* 64bit itable not supported */
393	+ errnum = ERR_FILELENGTH;
394	+ return -1;
395	+ }
396	+ ino_blk = ext4_gdp->bg_inode_table +
397	(((current_ino - 1) % (SUPERBLOCK->s_inodes_per_group))
398	>> log2 (EXT2_BLOCK_SIZE (SUPERBLOCK) / sizeof (struct ext2_inode)));
399	#ifdef E2DEBUG
400	@@ -629,7 +862,10 @@
401	}
402	linkbuf[filemax + len] = '\0';
403
404	- /* Read the symlink data. */
405	+ /* Read the symlink data.
406	+ * Slow symlink is extents enabled
407	+ * But since grub_read invokes ext2fs_read, nothing to change here
408	+ */
409	if (! ext2_is_fast_symlink ())
410	{
411	/* Read the necessary blocks, and reset the file pointer. */
412	@@ -640,7 +876,9 @@
413	}
414	else
415	{
416	- /* Copy the data directly from the inode. */
417	+ /* Copy the data directly from the inode.
418	+ * Fast symlink is not extents enabled
419	+ */
420	len = filemax;
421	memmove (linkbuf, (char *) INODE->i_block, len);
422	}
423	@@ -674,7 +912,13 @@
424	errnum = ERR_BAD_FILETYPE;
425	return 0;
426	}
427	-
428	+ /* if file is too large, just stop and report an error*/
429	+ if ( (INODE->i_flags & EXT4_HUGE_FILE_FL) && !(INODE->i_size_high))
430	+ {
431	+ /* file too large, stop reading */
432	+ errnum = ERR_FILELENGTH;
433	+ return 0;
434	+ }
435	filemax = (INODE->i_size);
436	return 1;
437	}
438	@@ -728,17 +972,28 @@
439	}
440
441	/* else, find the (logical) block component of our location */
442	+ /* ext4 logical block number the same as ext2/3 */
443	blk = loc >> EXT2_BLOCK_SIZE_BITS (SUPERBLOCK);
444
445	/* we know which logical block of the directory entry we are looking
446	for, now we have to translate that to the physical (fs) block on
447	the disk */
448	+ /* map extents enabled logical block number to physical fs on-disk block number */
449	+ if (EXT4_HAS_INCOMPAT_FEATURE(SUPERBLOCK,EXT4_FEATURE_INCOMPAT_EXTENTS)
450	+ && INODE->i_flags & EXT4_EXTENTS_FL)
451	+ map = ext4fs_block_map (blk);
452	+ else
453	map = ext2fs_block_map (blk);
454	#ifdef E2DEBUG
455	printf ("fs block=%d\n", map);
456	#endif /* E2DEBUG */
457	mapblock2 = -1;
458	- if ((map < 0) \|\| !ext2_rdfsb (map, DATABLOCK2))
459	+ if (map < 0)
460	+ {
461	+ *rest = ch;
462	+ return 0;
463	+ }
464	+ if (!ext2_rdfsb (map, DATABLOCK2))
465	{
466	errnum = ERR_FSYS_CORRUPT;
467	*rest = ch;