FLEX_BG support for the e2fsprogs interim branch.

index 0b17c48..581e8fe 100644
@@ -584,8 +584,11 @@ void check_super_block(e2fsck_t ctx)
 	for (i = 0, gd=fs->group_desc; i < fs->group_desc_count; i++, gd++) {
 		pctx.group = i;
 
-		first_block = ext2fs_group_first_block(fs, i);
-		last_block = ext2fs_group_last_block(fs, i);
+		if (!EXT2_HAS_INCOMPAT_FEATURE(fs->super,
+					       EXT4_FEATURE_INCOMPAT_FLEX_BG)) {
+			first_block = ext2fs_group_first_block(fs, i);
+			last_block = ext2fs_group_last_block(fs, i);
+		}
 
 		if ((gd->bg_block_bitmap < first_block) ||
 		    (gd->bg_block_bitmap > last_block)) {

index f111ddd..a9791b4 100644
@@ -67,6 +67,8 @@ static struct feature feature_list[] = {
 			"extent" },
 	{	E2P_FEATURE_INCOMPAT, EXT4_FEATURE_INCOMPAT_64BIT,
 			"64bit" },
+	{       E2P_FEATURE_INCOMPAT, EXT4_FEATURE_INCOMPAT_FLEX_BG,
+			"flex_bg"},
 	{       E2P_FEATURE_INCOMPAT, EXT4_FEATURE_INCOMPAT_MMP,
 			"mmp" },
 	{	0, 0, 0 },

index 146f9e5..900b179 100644
@@ -33,13 +33,16 @@ errcode_t ext2fs_check_desc(ext2_filsys fs)
 {
 	dgrp_t i;
 	blk_t first_block = fs->super->s_first_data_block;
-	blk_t last_block;
+	blk_t last_block = fs->super->s_blocks_count-1;
 
 	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
 
 	for (i = 0; i < fs->group_desc_count; i++) {
-		first_block = ext2fs_group_first_block(fs, i);
-		last_block = ext2fs_group_last_block(fs, i);
+		if (!EXT2_HAS_INCOMPAT_FEATURE(fs->super,
+					       EXT4_FEATURE_INCOMPAT_FLEX_BG)) {
+			first_block = ext2fs_group_first_block(fs, i);
+			last_block = ext2fs_group_last_block(fs, i);
+		}
 
 		/*
 		 * Check to make sure block bitmap for group is

index 9218e42..412b49b 100644
@@ -661,6 +661,7 @@ struct ext2_super_block {
 #define EXT3_FEATURE_INCOMPAT_EXTENTS		0x0040
 #define EXT4_FEATURE_INCOMPAT_64BIT		0x0080
 #define EXT4_FEATURE_INCOMPAT_MMP		0x0100
+#define EXT4_FEATURE_INCOMPAT_FLEX_BG		0x0200
 
 
 #define EXT2_FEATURE_COMPAT_SUPP	0

index 1d86fa1..b34aff1 100644
@@ -482,14 +482,16 @@ typedef struct ext2_icount *ext2_icount_t;
 					 EXT2_FEATURE_INCOMPAT_META_BG|\
 					 EXT3_FEATURE_INCOMPAT_EXTENTS|\
 					 EXT3_FEATURE_INCOMPAT_RECOVER|\
-					 EXT4_FEATURE_INCOMPAT_MMP)
+					 EXT4_FEATURE_INCOMPAT_MMP|\
+					 EXT4_FEATURE_INCOMPAT_FLEX_BG)
 #else
 #define EXT2_LIB_FEATURE_INCOMPAT_SUPP	(EXT2_FEATURE_INCOMPAT_FILETYPE|\
 					 EXT3_FEATURE_INCOMPAT_JOURNAL_DEV|\
 					 EXT2_FEATURE_INCOMPAT_META_BG|\
 					 EXT3_FEATURE_INCOMPAT_EXTENTS|\
 					 EXT3_FEATURE_INCOMPAT_RECOVER|\
-					 EXT4_FEATURE_INCOMPAT_MMP)
+					 EXT4_FEATURE_INCOMPAT_MMP|\
+					 EXT4_FEATURE_INCOMPAT_FLEX_BG)
 #endif
 #define EXT2_LIB_FEATURE_RO_COMPAT_SUPP	(EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER|\
 					 EXT2_FEATURE_RO_COMPAT_LARGE_FILE|\

index 8210c3b..0184af7 100644
@@ -922,7 +922,8 @@ static __u32 ok_features[3] = {
 	EXT2_FEATURE_INCOMPAT_FILETYPE|		/* Incompat */
 		EXT3_FEATURE_INCOMPAT_JOURNAL_DEV|
 		EXT2_FEATURE_INCOMPAT_META_BG|
-		EXT4_FEATURE_INCOMPAT_MMP,
+		EXT4_FEATURE_INCOMPAT_MMP|
+		EXT4_FEATURE_INCOMPAT_FLEX_BG,
 	EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER|	/* R/O compat */
 		EXT4_FEATURE_RO_COMPAT_GDT_CSUM
 };

index fad4812..d37ceb1 100644
@@ -303,6 +303,7 @@ static void update_feature_set(ext2_filsys fs, char *features)
 {
 	int sparse, old_sparse, filetype, old_filetype;
 	int journal, old_journal, dxdir, old_dxdir, uninit;
+	int flex_bg, old_flex_bg;
 	int mmp, old_mmp;
 	struct ext2_super_block *sb= fs->super;
 	int dir_nlink, old_dir_nlink;

@@ -319,6 +320,8 @@ static void update_feature_set(ext2_filsys fs, char *features)
 		EXT4_FEATURE_RO_COMPAT_DIR_NLINK;
 	old_filetype = sb->s_feature_incompat &
 		EXT2_FEATURE_INCOMPAT_FILETYPE;
+	old_flex_bg = sb->s_feature_incompat &
+		EXT4_FEATURE_INCOMPAT_FLEX_BG;
 	old_journal = sb->s_feature_compat &
 		EXT3_FEATURE_COMPAT_HAS_JOURNAL;
 	old_dxdir = sb->s_feature_compat &

@@ -339,6 +342,8 @@ static void update_feature_set(ext2_filsys fs, char *features)
 		EXT4_FEATURE_RO_COMPAT_DIR_NLINK;
 	filetype = sb->s_feature_incompat &
 		EXT2_FEATURE_INCOMPAT_FILETYPE;
+	flex_bg = sb->s_feature_incompat &
+		EXT4_FEATURE_INCOMPAT_FLEX_BG;
 	journal = sb->s_feature_compat &
 		EXT3_FEATURE_COMPAT_HAS_JOURNAL;
 	dxdir = sb->s_feature_compat &

@@ -407,6 +412,14 @@ static void update_feature_set(ext2_filsys fs, char *features)
 			 "update interval has been set to %d seconds.\n"),
 		       sb->s_mmp_update_interval);
 	}
+	if (!flex_bg && old_flex_bg) {
+		if (ext2fs_check_desc(fs)) {
+			fputs(_("Clearing the flex_bg flag would "
+				"cause the the filesystem to be\n"
+				"inconsistent.\n"), stderr);
+			exit(1);
+		}
+	}
 
 	if (old_mmp && !mmp) {
 		blk_t mmp_block;

169 lines not on this page · raw message

index 659ee27..86ef29a 100644
@@ -100,8 +100,9 @@ int ext2fs_super_and_bgd_loc(ext2_filsys fs,
 			numblocks--;
 		}
 	}
-		
-	numblocks -= 2 + fs->inode_blocks_per_group;
+
+	if (!fs->super->s_log_groups_per_flex)
+		numblocks -= 2 + fs->inode_blocks_per_group;
 
 	if (ret_super_blk)
 		*ret_super_blk = super_blk;

index 412b49b..caaeba2 100644
@@ -174,6 +174,7 @@ struct ext4_group_desc
 #define EXT2_BG_INODE_UNINIT	0x0001 /* Inode table/bitmap not initialized */
 #define EXT2_BG_BLOCK_UNINIT	0x0002 /* Block bitmap not initialized */
 #define EXT2_BG_INODE_ZEROED	0x0004 /* On-disk itable initialized to zero */
+#define EXT2_BG_FLEX_METADATA	0x0008 /* FLEX_BG block group contains meta-data */
 
 /*
  * Data structures used by the directory indexing feature

@@ -598,7 +599,10 @@ struct ext2_super_block {
 	__u16	s_mmp_update_interval;	/* # seconds to wait in MMP checking */
 	__u64	s_mmp_block;		/* Block for multi-mount protection */
 	__u32	s_raid_stripe_width;	/* blocks on all data disks (N*stride)*/
-	__u32	s_reserved[163];	/* Padding to the end of the block */
+	__u8    s_log_groups_per_flex;  /* FLEX_BG group size */
+	__u8    s_reserved_char_pad;
+	__u16   s_reserved_pad;         /* Padding to next 32bits */
+	__u32	s_reserved[162];	/* Padding to the end of the block */
 };
 
 /*

index 1916655..c3939e5 100644
@@ -159,6 +159,7 @@ errcode_t ext2fs_initialize(const char *name, int flags,
 	set_field(s_raid_stride, 0);		/* default stride size: 0 */
 	set_field(s_raid_stripe_width, 0);	/* default stripe width: 0 */
 	set_field(s_flags, 0);
+	set_field(s_log_groups_per_flex, 0);
 	if (super->s_feature_incompat & ~EXT2_LIB_FEATURE_INCOMPAT_SUPP) {
 		retval = EXT2_ET_UNSUPP_FEATURE;
 		goto cleanup;

@@ -366,7 +367,10 @@ ipg_retry:
 	 * group, and fill in the correct group statistics for group.
 	 * Note that although the block bitmap, inode bitmap, and
 	 * inode table have not been allocated (and in fact won't be
-	 * by this routine), they are accounted for nevertheless.
+	 * by this routine), they are accounted for nevertheless.  If
+	 * FLEX_BG meta-data grouping is used, only account for the
+	 * superblock and group descriptors (the inode tables and
+	 * bitmaps will be accounted for when allocated).
 	 */
 	super->s_free_blocks_count = 0;
 	for (i = 0; i < fs->group_desc_count; i++) {

index 0184af7..40dac03 100644
@@ -96,7 +96,7 @@ static void usage(void)
 {
 	fprintf(stderr, _("Usage: %s [-c|-t|-l filename] [-b block-size] "
 	"[-f fragment-size]\n\t[-i bytes-per-inode] [-I inode-size] "
-	"[-j] [-J journal-options]\n"
+	"[-j] [-J journal-options] [-G meta group size]\n"
 	"\t[-N number-of-inodes] [-m reserved-blocks-percentage] "
 	"[-o creator-os]\n\t[-g blocks-per-group] [-L volume-label] "
 	"[-M last-mounted-directory]\n\t[-O feature[,...]] "

@@ -476,7 +476,8 @@ static void setup_lazy_bg(ext2_filsys fs)
 			 * group because it may need block bitmap padding. */
 			if ((ext2fs_bg_has_super(fs, i) &&
 			     sb->s_reserved_gdt_blocks) ||
-			    i == fs->group_desc_count - 1)
+			    i == fs->group_desc_count - 1 ||
+			    (bg->bg_flags & EXT2_BG_FLEX_METADATA))
 				continue;
 
 			blks = ext2fs_super_and_bgd_loc(fs, i, 0, 0, 0, 0);

@@ -962,6 +963,7 @@ static void PRS(int argc, char *argv[])
 	int		blocksize = 0;
 	int		inode_ratio = 0;
 	int		inode_size = 0;
+	unsigned long	flex_bg_size = 0;
 	double		reserved_ratio = 5.0;
 	int		sector_size = 0;
 	int		show_version_only = 0;

@@ -1044,7 +1046,7 @@ static void PRS(int argc, char *argv[])
 	}
 
 	while ((c = getopt (argc, argv,
-		    "b:cf:g:i:jl:m:no:qr:s:tvE:FI:J:L:M:N:O:R:ST:V")) != EOF) {
+		    "b:cf:g:G:i:jl:m:no:qr:s:tvE:FI:J:L:M:N:O:R:ST:V")) != EOF) {
 		switch (c) {
 		case 'b':
 			blocksize = strtol(optarg, &tmp, 0);

@@ -1095,6 +1097,20 @@ static void PRS(int argc, char *argv[])
 				exit(1);
 			}
 			break;
+		case 'G':
+			flex_bg_size = strtoul(optarg, &tmp, 0);
+			if (*tmp) {
+				com_err(program_name, 0,
+					_("Illegal number for Flex_BG size"));
+				exit(1);
+			}
+			if (flex_bg_size < 2 ||
+			    (flex_bg_size & (flex_bg_size-1)) != 0) {
+				com_err(program_name, 0,
+					_("Flex_BG size must be a power of 2"));
+				exit(1);
+			}
+			break;
 		case 'i':
 			inode_ratio = strtoul(optarg, &tmp, 0);
 			if (inode_ratio < EXT2_MIN_BLOCK_SIZE ||

@@ -1490,6 +1506,9 @@ static void PRS(int argc, char *argv[])
 		}
 	}
 
+	if (flex_bg_size)
+		fs_param.s_log_groups_per_flex = int_log2(flex_bg_size);
+
 	if (!force && fs_param.s_blocks_count >= ((unsigned) 1 << 31)) {
 		com_err(program_name, 0,
 			_("Filesystem too large.  No more than 2**31-1 blocks\n"