1Index: grub-0.97/stage2/fsys_ext2fs.c
2===================================================================
3--- grub-0.97.orig/stage2/fsys_ext2fs.c
4+++ grub-0.97/stage2/fsys_ext2fs.c
5@@ -41,6 +41,7 @@ typedef __signed__ short __s16;
6 typedef unsigned short __u16;
7 typedef __signed__ int __s32;
8 typedef unsigned int __u32;
9+typedef unsigned long long __u64;
10
11 /*
12  * Constants relative to the data blocks, from ext2_fs.h
13@@ -51,7 +52,7 @@ typedef unsigned int __u32;
14 #define EXT2_TIND_BLOCK                 (EXT2_DIND_BLOCK + 1)
15 #define EXT2_N_BLOCKS                   (EXT2_TIND_BLOCK + 1)
16
17-/* include/linux/ext2_fs.h */
18+/* lib/ext2fs/ext2_fs.h from e2fsprogs */
19 struct ext2_super_block
20   {
21     __u32 s_inodes_count;	/* Inodes count */
22@@ -61,9 +62,9 @@ struct ext2_super_block
23     __u32 s_free_inodes_count;	/* Free inodes count */
24     __u32 s_first_data_block;	/* First Data Block */
25     __u32 s_log_block_size;	/* Block size */
26-    __s32 s_log_frag_size;	/* Fragment size */
27+    __s32 s_obso_log_frag_size;	/* Obsoleted Fragment size */
28     __u32 s_blocks_per_group;	/* # Blocks per group */
29-    __u32 s_frags_per_group;	/* # Fragments per group */
30+    __u32 s_obso_frags_per_group;	/* Obsoleted Fragments per group */
31     __u32 s_inodes_per_group;	/* # Inodes per group */
32     __u32 s_mtime;		/* Mount time */
33     __u32 s_wtime;		/* Write time */
34@@ -72,7 +73,7 @@ struct ext2_super_block
35     __u16 s_magic;		/* Magic signature */
36     __u16 s_state;		/* File system state */
37     __u16 s_errors;		/* Behaviour when detecting errors */
38-    __u16 s_pad;
39+    __u16 s_minor_rev_level;	/* minor revision level */
40     __u32 s_lastcheck;		/* time of last check */
41     __u32 s_checkinterval;	/* max. time between checks */
42     __u32 s_creator_os;		/* OS */
43@@ -119,15 +120,29 @@ struct ext2_super_block
44     __u32 s_hash_seed[4];	/* HTREE hash seed */
45     __u8  s_def_hash_version;	/* Default hash version to use */
46     __u8  s_jnl_backup_type; 	/* Default type of journal backup */
47-    __u16 s_reserved_word_pad;
48+    __u16 s_desc_size;		/* size of group descriptor */
49     __u32 s_default_mount_opts;
50     __u32 s_first_meta_bg;	/* First metablock group */
51     __u32 s_mkfs_time;		/* When the filesystem was created */
52     __u32 s_jnl_blocks[17]; 	/* Backup of the journal inode */
53-    __u32 s_reserved[172];	/* Padding to the end of the block */
54-  };
55+    /* 64bit desc support valid if EXT4_FEATURE_INCOMPAT_64BIT */
56+    __u32 s_blocks_count_hi;	/* Blocks count */
57+    __u32 s_r_blocks_count_hi;	/* Reserved blocks count */
58+    __u32 s_free_blocks_count_hi; /* Free blocks count */
59+    __u16 s_min_extra_isize;	/* All inodes have at least # bytes */
60+    __u16 s_max_extra_isize;	/* New inodes should reverve # bytes */
61+    __u32 s_flags;		/* Miscellaneous flags */
62+    __u16 s_raid_stride;	/* Raid stride */
63+    __u16 s_mmp_interval;	/* # seconds to wait MMP checking */
64+    __u64 s_mmp_block;		/* Block for multi-mount protection */
65+    __u32 s_raid_stripe_width;	/* Blocks on all data disks (N*stride)*/
66+    __u8  s_log_groups_per_flex;/* FLEX_BG group size*/
67+    __u8  s_reserved_char_pad;
68+    __u16 s_reserved_pad;
69+    __u32 s_reserved[162];	/* Padding to the end of the block */
70+};
71
72-struct ext2_group_desc
73+struct ext4_group_desc
74   {
75     __u32 bg_block_bitmap;	/* Blocks bitmap block */
76     __u32 bg_inode_bitmap;	/* Inodes bitmap block */
77@@ -135,8 +150,18 @@ struct ext2_group_desc
78     __u16 bg_free_blocks_count;	/* Free blocks count */
79     __u16 bg_free_inodes_count;	/* Free inodes count */
80     __u16 bg_used_dirs_count;	/* Directories count */
81-    __u16 bg_pad;
82-    __u32 bg_reserved[3];
83+    __u16 bg_flags;		/* EXT4_BG_flags (INODE_UNINIT, etc) */
84+    __u32 bg_reserved[2];		/* Likely block/inode bitmap checksum */
85+    __u16 bg_itable_unused;	/* Unused inodes count */
86+    __u16 bg_checksum;		/* crc16(sb_uuid+group+desc) */
87+    __u32 bg_block_bitmap_hi;	/* Blocks bitmap block MSB */
88+    __u32 bg_inode_bitmap_hi;	/* Inodes bitmap block MSB */
89+    __u32 bg_inode_table_hi;	/* Inodes table block MSB */
90+    __u16 bg_free_blocks_count_hi;/* Free blocks count MSB */
91+    __u16 bg_free_inodes_count_hi;/* Free inodes count MSB */
92+    __u16 bg_used_dirs_count_hi;	/* Directories count MSB */
93+    __u16 bg_itable_unused_hi;	/* Unused inodes count MSB */
94+    __u32 bg_reserved2[3];
95   };
96
97 struct ext2_inode
98@@ -174,22 +199,22 @@ struct ext2_inode
99     __u32 i_block[EXT2_N_BLOCKS];	/* 40: Pointers to blocks */
100     __u32 i_version;		/* File version (for NFS) */
101     __u32 i_file_acl;		/* File ACL */
102-    __u32 i_dir_acl;		/* Directory ACL */
103-    __u32 i_faddr;		/* Fragment address */
104+    __u32 i_size_high;
105+    __u32 i_obso_faddr;		/* Obsoleted fragment address */
106     union
107       {
108 	struct
109 	  {
110-	    __u8 l_i_frag;	/* Fragment number */
111-	    __u8 l_i_fsize;	/* Fragment size */
112-	    __u16 i_pad1;
113-	    __u32 l_i_reserved2[2];
114+		__u16	l_i_blocks_high; /* were l_i_reserved1 */
115+		__u16	l_i_file_acl_high;
116+		__u16	l_i_uid_high;	/* these 2 fields */
117+		__u16	l_i_gid_high;	/* were reserved2[0] */
118+		__u32	l_i_reserved2;
119 	  }
120 	linux2;
121 	struct
122 	  {
123-	    __u8 h_i_frag;	/* Fragment number */
124-	    __u8 h_i_fsize;	/* Fragment size */
125+		__u16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
126 	    __u16 h_i_mode_high;
127 	    __u16 h_i_uid_high;
128 	    __u16 h_i_gid_high;
129@@ -198,16 +223,36 @@ struct ext2_inode
130 	hurd2;
131 	struct
132 	  {
133-	    __u8 m_i_frag;	/* Fragment number */
134-	    __u8 m_i_fsize;	/* Fragment size */
135-	    __u16 m_pad1;
136+		__u16	h_i_reserved1;	/* Obsoleted fragment number/size which are removed in ext4 */
137+		__u16	m_i_file_acl_high;
138 	    __u32 m_i_reserved2[2];
139 	  }
140 	masix2;
141       }
142     osd2;			/* OS dependent 2 */
143+	__u16	i_extra_isize;
144+	__u16	i_pad1;
145+	__u32  i_ctime_extra;  /* extra Change time      (nsec << 2 | epoch) */
146+	__u32  i_mtime_extra;  /* extra Modification time(nsec << 2 | epoch) */
147+	__u32  i_atime_extra;  /* extra Access time      (nsec << 2 | epoch) */
148+	__u32  i_crtime;       /* File Creation time */
149+	__u32  i_crtime_extra; /* extra FileCreationtime (nsec << 2 | epoch) */
150+	__u32  i_version_hi;	/* high 32 bits for 64-bit version */
151   };
152
153+#define EXT4_FEATURE_INCOMPAT_EXTENTS		0x0040 /* extents support */
154+#define EXT4_FEATURE_INCOMPAT_64BIT			0x0080 /* grub not supported*/
155+#define EXT4_FEATURE_INCOMPAT_MMP           0x0100
156+#define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
157+
158+#define EXT4_HAS_INCOMPAT_FEATURE(sb,mask)			\
159+	( sb->s_feature_incompat & mask )
160+
161+#define EXT4_EXTENTS_FL		0x00080000 /* Inode uses extents */
162+#define EXT4_HUGE_FILE_FL	0x00040000 /* Set to each huge file */
163+
164+#define EXT4_MIN_DESC_SIZE			32
165+
166 /* linux/limits.h */
167 #define NAME_MAX         255	/* # chars in a file name */
168
169@@ -225,6 +270,57 @@ struct ext2_dir_entry
170     char name[EXT2_NAME_LEN];	/* File name */
171   };
172
173+/* linux/ext4_fs_extents.h */
174+/* This is the extent on-disk structure.
175+ * It's used at the bottom of the tree.
176+ */
177+struct ext4_extent
178+  {
179+	__u32  ee_block;   /* first logical block extent covers */
180+	__u16  ee_len;     /* number of blocks covered by extent */
181+	__u16  ee_start_hi;    /* high 16 bits of physical block */
182+	__u32  ee_start_lo;    /* low 32 bits of physical block */
183+  };
184+
185+/*
186+ * This is index on-disk structure.
187+ * It's used at all the levels except the bottom.
188+ */
189+struct ext4_extent_idx
190+  {
191+    __u32  ei_block;   /* index covers logical blocks from 'block' */
192+    __u32  ei_leaf_lo; /* pointer to the physical block of the next *
193+	                     * level. leaf or next index could be there */
194+    __u16  ei_leaf_hi; /* high 16 bits of physical block */
195+    __u16  ei_unused;
196+  };
197+
198+/*
199+ * Each block (leaves and indexes), even inode-stored has header.
200+ */
201+struct ext4_extent_header
202+  {
203+    __u16  eh_magic;   /* probably will support different formats */
204+    __u16  eh_entries; /* number of valid entries */
205+    __u16  eh_max;     /* capacity of store in entries */
206+    __u16  eh_depth;   /* has tree real underlying blocks? */
207+    __u32  eh_generation;  /* generation of the tree */
208+  };
209+
210+#define EXT4_EXT_MAGIC      (0xf30a)
211+#define EXT_FIRST_EXTENT(__hdr__) \
212+    ((struct ext4_extent *) (((char *) (__hdr__)) +     \
213+                 sizeof(struct ext4_extent_header)))
214+#define EXT_FIRST_INDEX(__hdr__) \
215+    ((struct ext4_extent_idx *) (((char *) (__hdr__)) + \
216+                 sizeof(struct ext4_extent_header)))
217+#define EXT_LAST_EXTENT(__hdr__) \
218+    (EXT_FIRST_EXTENT((__hdr__)) + (__u16)((__hdr__)->eh_entries) - 1)
219+#define EXT_LAST_INDEX(__hdr__) \
220+    (EXT_FIRST_INDEX((__hdr__)) + (__u16)((__hdr__)->eh_entries) - 1)
221+
222+
223+
224 /* linux/ext2fs.h */
225 /*
226  * EXT2_DIR_PAD defines the directory entries boundaries
227@@ -271,8 +367,17 @@ struct ext2_dir_entry
228 /* kind of from ext2/super.c */
229 #define EXT2_BLOCK_SIZE(s)	(1 << EXT2_BLOCK_SIZE_BITS(s))
230 /* linux/ext2fs.h */
231+/* sizeof(struct ext2_group_desc) is changed in ext4
232+ * in kernel code, ext2/3 uses sizeof(struct ext2_group_desc) to calculate
233+ * number of desc per block, while ext4 uses superblock->s_desc_size in stead
234+ * superblock->s_desc_size is not available in ext2/3
235+ * */
236+#define EXT2_DESC_SIZE(s) \
237+	(EXT4_HAS_INCOMPAT_FEATURE(s,EXT4_FEATURE_INCOMPAT_64BIT)? \
238+	s->s_desc_size : EXT4_MIN_DESC_SIZE)
239 #define EXT2_DESC_PER_BLOCK(s) \
240-     (EXT2_BLOCK_SIZE(s) / sizeof (struct ext2_group_desc))
241+	(EXT2_BLOCK_SIZE(s) / EXT2_DESC_SIZE(s))
242+
243 /* linux/stat.h */
244 #define S_IFMT  00170000
245 #define S_IFLNK  0120000
246@@ -434,6 +539,122 @@ ext2fs_block_map (int logical_block)
247     [logical_block & (EXT2_ADDR_PER_BLOCK (SUPERBLOCK) - 1)];
248 }
249
250+/* extent binary search index
251+ * find closest index in the current level extent tree
252+ * kind of from ext4_ext_binsearch_idx in ext4/extents.c
253+ */
254+static struct ext4_extent_idx*
255+ext4_ext_binsearch_idx(struct ext4_extent_header* eh, int logical_block)
256+{
257+  struct ext4_extent_idx *r, *l, *m;
258+  l = EXT_FIRST_INDEX(eh) + 1;
259+  r = EXT_LAST_INDEX(eh);
260+  while (l <= r)
261+    {
262+	  m = l + (r - l) / 2;
263+	  if (logical_block < m->ei_block)
264+		  r = m - 1;
265+	  else
266+		  l = m + 1;
267+	}
268+  return (struct ext4_extent_idx*)(l - 1);
269+}
270+
271+/* extent binary search
272+ * find closest extent in the leaf level
273+ * kind of from ext4_ext_binsearch in ext4/extents.c
274+ */
275+static struct ext4_extent*
276+ext4_ext_binsearch(struct ext4_extent_header* eh, int logical_block)
277+{
278+  struct ext4_extent *r, *l, *m;
279+  l = EXT_FIRST_EXTENT(eh) + 1;
280+  r = EXT_LAST_EXTENT(eh);
281+  while (l <= r)
282+    {
283+	  m = l + (r - l) / 2;
284+	  if (logical_block < m->ee_block)
285+		  r = m - 1;
286+	  else
287+		  l = m + 1;
288+	}
289+  return (struct ext4_extent*)(l - 1);
290+}
291+
292+/* Maps extents enabled logical block into physical block via an inode.
293+ * EXT4_HUGE_FILE_FL should be checked before calling this.
294+ */
295+static int
296+ext4fs_block_map (int logical_block)
297+{
298+  struct ext4_extent_header *eh;
299+  struct ext4_extent *ex, *extent;
300+  struct ext4_extent_idx *ei, *index;
301+  int depth;
302+  int i;
303+
304+#ifdef E2DEBUG
305+  unsigned char *i;
306+  for (i = (unsigned char *) INODE;
307+       i < ((unsigned char *) INODE + sizeof (struct ext2_inode));
308+       i++)
309+    {
310+      printf ("%c", "0123456789abcdef"[*i >> 4]);
311+      printf ("%c", "0123456789abcdef"[*i % 16]);
312+      if (!((i + 1 - (unsigned char *) INODE) % 16))
313+	{
314+	  printf ("\n");
315+	}
316+      else
317+	{
318+	  printf (" ");
319+	}
320+    }
321+  printf ("logical block %d\n", logical_block);
322+#endif /* E2DEBUG */
323+  eh = (struct ext4_extent_header*)INODE->i_block;
324+  if (eh->eh_magic != EXT4_EXT_MAGIC)
325+  {
326+          errnum = ERR_FSYS_CORRUPT;
327+          return -1;
328+  }
329+  while((depth = eh->eh_depth) != 0)
330+  	{ /* extent index */
331+	  if (eh->eh_magic != EXT4_EXT_MAGIC)
332+	  {
333+	          errnum = ERR_FSYS_CORRUPT;
334+		  return -1;
335+	  }
336+	  ei = ext4_ext_binsearch_idx(eh, logical_block);
337+	  if (ei->ei_leaf_hi)
338+	{/* 64bit physical block number not supported */
339+	  errnum = ERR_FILELENGTH;
340+	  return -1;
341+	}
342+	  if (!ext2_rdfsb(ei->ei_leaf_lo, DATABLOCK1))
343+	{
344+	  errnum = ERR_FSYS_CORRUPT;
345+	  return -1;
346+	}
347+	  eh = (struct ext4_extent_header*)DATABLOCK1;
348+  	}
349+
350+  /* depth==0, we come to the leaf */
351+  ex = ext4_ext_binsearch(eh, logical_block);
352+  if (ex->ee_start_hi)
353+	{/* 64bit physical block number not supported */
354+	  errnum = ERR_FILELENGTH;
355+	  return -1;
356+	}
357+  if ((ex->ee_block + ex->ee_len) < logical_block)
358+	{
359+	  errnum = ERR_FSYS_CORRUPT;
360+	  return -1;
361+	}
362+  return ex->ee_start_lo + logical_block - ex->ee_block;
363+
364+}
365+
366 /* preconditions: all preconds of ext2fs_block_map */
367 int
368 ext2fs_read (char *buf, int len)
369@@ -468,6 +689,11 @@ ext2fs_read (char *buf, int len)
370       /* find the (logical) block component of our location */
371       logical_block = filepos >> EXT2_BLOCK_SIZE_BITS (SUPERBLOCK);
372       offset = filepos & (EXT2_BLOCK_SIZE (SUPERBLOCK) - 1);
373+      /* map extents enabled logical block number to physical fs on-disk block number */
374+      if (EXT4_HAS_INCOMPAT_FEATURE(SUPERBLOCK,EXT4_FEATURE_INCOMPAT_EXTENTS)
375+                    && INODE->i_flags & EXT4_EXTENTS_FL)
376+          map = ext4fs_block_map (logical_block);
377+      else
378       map = ext2fs_block_map (logical_block);
379 #ifdef E2DEBUG
380       printf ("map=%d\n", map);
381@@ -552,7 +778,7 @@ ext2fs_dir (char *dirname)
382   int desc;			/* index within that group */
383   int ino_blk;			/* fs pointer of the inode's information */
384   int str_chk = 0;		/* used to hold the results of a string compare */
385-  struct ext2_group_desc *gdp;
386+  struct ext4_group_desc *ext4_gdp;
387   struct ext2_inode *raw_inode;	/* inode info corresponding to current_ino */
388
389   char linkbuf[PATH_MAX];	/* buffer for following symbolic links */
390@@ -598,8 +824,15 @@ ext2fs_dir (char *dirname)
391 	{
392 	  return 0;
393 	}
394-      gdp = GROUP_DESC;
395-      ino_blk = gdp[desc].bg_inode_table +
396+	  ext4_gdp = (struct ext4_group_desc *)( (__u8*)GROUP_DESC +
397+			  		desc * EXT2_DESC_SIZE(SUPERBLOCK));
398+	  if (EXT4_HAS_INCOMPAT_FEATURE(SUPERBLOCK, EXT4_FEATURE_INCOMPAT_64BIT)
399+		&& (! ext4_gdp->bg_inode_table_hi))
400+	{/* 64bit itable not supported */
401+	  errnum = ERR_FILELENGTH;
402+	  return -1;
403+	}
404+      ino_blk = ext4_gdp->bg_inode_table +
405 	(((current_ino - 1) % (SUPERBLOCK->s_inodes_per_group))
406 	 >> log2 (EXT2_INODES_PER_BLOCK (SUPERBLOCK)));
407 #ifdef E2DEBUG
408@@ -676,7 +909,10 @@ ext2fs_dir (char *dirname)
409 	    }
410 	  linkbuf[filemax + len] = '\0';
411
412-	  /* Read the symlink data. */
413+	  /* Read the symlink data.
414+	   * Slow symlink is extents enabled
415+	   * But since grub_read invokes ext2fs_read, nothing to change here
416+	   */
417 	  if (! ext2_is_fast_symlink ())
418 	    {
419 	      /* Read the necessary blocks, and reset the file pointer. */
420@@ -687,7 +923,9 @@ ext2fs_dir (char *dirname)
421 	    }
422 	  else
423 	    {
424-	      /* Copy the data directly from the inode. */
425+	      /* Copy the data directly from the inode.
426+	       * Fast symlink is not extents enabled
427+	       */
428 	      len = filemax;
429 	      memmove (linkbuf, (char *) INODE->i_block, len);
430 	    }
431@@ -721,6 +959,13 @@ ext2fs_dir (char *dirname)
432 	      errnum = ERR_BAD_FILETYPE;
433 	      return 0;
434 	    }
435+	  /* if file is too large, just stop and report an error*/
436+	  if ( (INODE->i_flags & EXT4_HUGE_FILE_FL) && !(INODE->i_size_high))
437+	    {
438+		  /* file too large, stop reading */
439+		  errnum = ERR_FILELENGTH;
440+		  return 0;
441+	    }
442
443 	  filemax = (INODE->i_size);
444 	  return 1;
445@@ -775,17 +1020,28 @@ ext2fs_dir (char *dirname)
446 	    }
447
448 	  /* else, find the (logical) block component of our location */
449+	  /* ext4 logical block number the same as ext2/3 */
450 	  blk = loc >> EXT2_BLOCK_SIZE_BITS (SUPERBLOCK);
451
452 	  /* we know which logical block of the directory entry we are looking
453 	     for, now we have to translate that to the physical (fs) block on
454 	     the disk */
455+	  /* map extents enabled logical block number to physical fs on-disk block number */
456+	  if (EXT4_HAS_INCOMPAT_FEATURE(SUPERBLOCK,EXT4_FEATURE_INCOMPAT_EXTENTS)
457+                        && INODE->i_flags & EXT4_EXTENTS_FL)
458+              map = ext4fs_block_map (blk);
459+	  else
460 	  map = ext2fs_block_map (blk);
461 #ifdef E2DEBUG
462 	  printf ("fs block=%d\n", map);
463 #endif /* E2DEBUG */
464 	  mapblock2 = -1;
465-	  if ((map < 0) || !ext2_rdfsb (map, DATABLOCK2))
466+	  if (map < 0)
467+	  {
468+	      *rest = ch;
469+	      return 0;
470+	  }
471+          if (!ext2_rdfsb (map, DATABLOCK2))
472 	    {
473 	      errnum = ERR_FSYS_CORRUPT;
474 	      *rest = ch;
475