evie/android_kernel_oneplus_msm8998
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

ext4: bigalloc changes to block bitmap initialization functions

Browse source 
Add bigalloc support to ext4_init_block_bitmap() and
ext4_free_blocks_after_init().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
Theodore Ts'o 2011-09-09 18:44:51 -04:00
parent fd034a84e1
commit d5b8f31007
2 changed files with 102 additions and 40 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

129
fs/ext4/balloc.c
View file

@ -23,9 +23,6 @@
#include <trace/events/ext4.h> #include <trace/events/ext4.h>
static unsigned int num_base_meta_blocks(struct super_block *sb,
ext4_group_t block_group);
/* /*
* balloc.c contains the blocks allocation and deallocation routines * balloc.c contains the blocks allocation and deallocation routines
*/ */
@ -58,37 +55,87 @@ static int ext4_block_in_group(struct super_block *sb, ext4_fsblk_t block,
return 0; return 0;
} }
static int ext4_group_used_meta_blocks(struct super_block *sb, /* Return the number of clusters used for file system metadata; this
ext4_group_t block_group, * represents the overhead needed by the file system.
struct ext4_group_desc *gdp) */
unsigned ext4_num_overhead_clusters(struct super_block *sb,
ext4_group_t block_group,
struct ext4_group_desc *gdp)
{ {
ext4_fsblk_t tmp; unsigned num_clusters;
int block_cluster = -1, inode_cluster = -1, itbl_cluster = -1, i, c;
ext4_fsblk_t start = ext4_group_first_block_no(sb, block_group);
ext4_fsblk_t itbl_blk;
struct ext4_sb_info *sbi = EXT4_SB(sb); struct ext4_sb_info *sbi = EXT4_SB(sb);
/* block bitmap, inode bitmap, and inode table blocks */
int used_blocks = sbi->s_itb_per_group + 2;
if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG)) { /* This is the number of clusters used by the superblock,
if (!ext4_block_in_group(sb, ext4_block_bitmap(sb, gdp), * block group descriptors, and reserved block group
block_group)) * descriptor blocks */
used_blocks--; num_clusters = ext4_num_base_meta_clusters(sb, block_group);
if (!ext4_block_in_group(sb, ext4_inode_bitmap(sb, gdp), /*
block_group)) * For the allocation bitmaps and inode table, we first need
used_blocks--; * to check to see if the block is in the block group. If it
* is, then check to see if the cluster is already accounted
tmp = ext4_inode_table(sb, gdp); * for in the clusters used for the base metadata cluster, or
for (; tmp < ext4_inode_table(sb, gdp) + * if we can increment the base metadata cluster to include
sbi->s_itb_per_group; tmp++) { * that block. Otherwise, we will have to track the cluster
if (!ext4_block_in_group(sb, tmp, block_group)) * used for the allocation bitmap or inode table explicitly.
used_blocks -= 1; * Normally all of these blocks are contiguous, so the special
* case handling shouldn't be necessary except for *very*
* unusual file system layouts.
*/
if (ext4_block_in_group(sb, ext4_block_bitmap(sb, gdp), block_group)) {
block_cluster = EXT4_B2C(sbi, (start -
ext4_block_bitmap(sb, gdp)));
if (block_cluster < num_clusters)
block_cluster = -1;
else if (block_cluster == num_clusters) {
num_clusters++;
block_cluster = -1;
} }
} }
return used_blocks;
if (ext4_block_in_group(sb, ext4_inode_bitmap(sb, gdp), block_group)) {
inode_cluster = EXT4_B2C(sbi,
start - ext4_inode_bitmap(sb, gdp));
if (inode_cluster < num_clusters)
inode_cluster = -1;
else if (inode_cluster == num_clusters) {
num_clusters++;
inode_cluster = -1;
}
}
itbl_blk = ext4_inode_table(sb, gdp);
for (i = 0; i < sbi->s_itb_per_group; i++) {
if (ext4_block_in_group(sb, itbl_blk + i, block_group)) {
c = EXT4_B2C(sbi, start - itbl_blk + i);
if ((c < num_clusters) || (c == inode_cluster) ||
(c == block_cluster) || (c == itbl_cluster))
continue;
if (c == num_clusters) {
num_clusters++;
continue;
}
num_clusters++;
itbl_cluster = c;
}
}
if (block_cluster != -1)
num_clusters++;
if (inode_cluster != -1)
num_clusters++;
return num_clusters;
} }
static unsigned int num_blocks_in_group(struct super_block *sb, static unsigned int num_clusters_in_group(struct super_block *sb,
ext4_group_t block_group) ext4_group_t block_group)
{ {
unsigned int blocks;
if (block_group == ext4_get_groups_count(sb) - 1) { if (block_group == ext4_get_groups_count(sb) - 1) {
/* /*
* Even though mke2fs always initializes the first and * Even though mke2fs always initializes the first and
@ -96,10 +143,11 @@ static unsigned int num_blocks_in_group(struct super_block *sb,
* we need to make sure we calculate the right free * we need to make sure we calculate the right free
* blocks. * blocks.
*/ */
return ext4_blocks_count(EXT4_SB(sb)->s_es) - blocks = ext4_blocks_count(EXT4_SB(sb)->s_es) -
ext4_group_first_block_no(sb, block_group); ext4_group_first_block_no(sb, block_group);
} else } else
return EXT4_BLOCKS_PER_GROUP(sb); blocks = EXT4_BLOCKS_PER_GROUP(sb);
return EXT4_NUM_B2C(EXT4_SB(sb), blocks);
} }
/* Initializes an uninitialized block bitmap */ /* Initializes an uninitialized block bitmap */
@ -107,7 +155,7 @@ void ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh,
ext4_group_t block_group, ext4_group_t block_group,
struct ext4_group_desc *gdp) struct ext4_group_desc *gdp)
{ {
unsigned int bit, bit_max = num_base_meta_blocks(sb, block_group); unsigned int bit, bit_max;
struct ext4_sb_info *sbi = EXT4_SB(sb); struct ext4_sb_info *sbi = EXT4_SB(sb);
ext4_fsblk_t start, tmp; ext4_fsblk_t start, tmp;
int flex_bg = 0; int flex_bg = 0;
@ -126,6 +174,7 @@ void ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh,
} }
memset(bh->b_data, 0, sb->s_blocksize); memset(bh->b_data, 0, sb->s_blocksize);
bit_max = ext4_num_base_meta_clusters(sb, block_group);
for (bit = 0; bit < bit_max; bit++) for (bit = 0; bit < bit_max; bit++)
ext4_set_bit(bit, bh->b_data); ext4_set_bit(bit, bh->b_data);
@ -137,24 +186,25 @@ void ext4_init_block_bitmap(struct super_block *sb, struct buffer_head *bh,
/* Set bits for block and inode bitmaps, and inode table */ /* Set bits for block and inode bitmaps, and inode table */
tmp = ext4_block_bitmap(sb, gdp); tmp = ext4_block_bitmap(sb, gdp);
if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) if (!flex_bg || ext4_block_in_group(sb, tmp, block_group))
ext4_set_bit(tmp - start, bh->b_data); ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);
tmp = ext4_inode_bitmap(sb, gdp); tmp = ext4_inode_bitmap(sb, gdp);
if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) if (!flex_bg || ext4_block_in_group(sb, tmp, block_group))
ext4_set_bit(tmp - start, bh->b_data); ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);
tmp = ext4_inode_table(sb, gdp); tmp = ext4_inode_table(sb, gdp);
for (; tmp < ext4_inode_table(sb, gdp) + for (; tmp < ext4_inode_table(sb, gdp) +
sbi->s_itb_per_group; tmp++) { sbi->s_itb_per_group; tmp++) {
if (!flex_bg || ext4_block_in_group(sb, tmp, block_group)) if (!flex_bg || ext4_block_in_group(sb, tmp, block_group))
ext4_set_bit(tmp - start, bh->b_data); ext4_set_bit(EXT4_B2C(sbi, tmp - start), bh->b_data);
} }
/* /*
* Also if the number of blocks within the group is less than * Also if the number of blocks within the group is less than
* the blocksize * 8 ( which is the size of bitmap ), set rest * the blocksize * 8 ( which is the size of bitmap ), set rest
* of the block bitmap to 1 * of the block bitmap to 1
*/ */
ext4_mark_bitmap_end(num_blocks_in_group(sb, block_group), ext4_mark_bitmap_end(num_clusters_in_group(sb, block_group),
sb->s_blocksize * 8, bh->b_data); sb->s_blocksize * 8, bh->b_data);
} }
@ -165,9 +215,8 @@ unsigned ext4_free_blocks_after_init(struct super_block *sb,
ext4_group_t block_group, ext4_group_t block_group,
struct ext4_group_desc *gdp) struct ext4_group_desc *gdp)
{ {
return num_blocks_in_group(sb, block_group) - return num_clusters_in_group(sb, block_group) -
num_base_meta_blocks(sb, block_group) - ext4_num_overhead_clusters(sb, block_group, gdp);
ext4_group_used_meta_blocks(sb, block_group, gdp);
} }
/* /*
@ -611,14 +660,14 @@ unsigned long ext4_bg_num_gdb(struct super_block *sb, ext4_group_t group)
} }
/* /*
* This function returns the number of file system metadata blocks at * This function returns the number of file system metadata clusters at
* the beginning of a block group, including the reserved gdt blocks. * the beginning of a block group, including the reserved gdt blocks.
*/ */
static unsigned int num_base_meta_blocks(struct super_block *sb, unsigned ext4_num_base_meta_clusters(struct super_block *sb,
ext4_group_t block_group) ext4_group_t block_group)
{ {
struct ext4_sb_info *sbi = EXT4_SB(sb); struct ext4_sb_info *sbi = EXT4_SB(sb);
int num; unsigned num;
/* Check for superblock and gdt backups in this group */ /* Check for superblock and gdt backups in this group */
num = ext4_bg_has_super(sb, block_group); num = ext4_bg_has_super(sb, block_group);
@ -633,7 +682,7 @@ static unsigned int num_base_meta_blocks(struct super_block *sb,
} else { /* For META_BG_BLOCK_GROUPS */ } else { /* For META_BG_BLOCK_GROUPS */
num += ext4_bg_num_gdb(sb, block_group); num += ext4_bg_num_gdb(sb, block_group);
} }
return num; return EXT4_NUM_B2C(sbi, num);
} }
/** /**
* ext4_inode_to_goal_block - return a hint for block allocation * ext4_inode_to_goal_block - return a hint for block allocation

13
fs/ext4/ext4.h
View file

@ -261,6 +261,14 @@ struct ext4_io_submit {
#endif #endif
#define EXT4_BLOCK_ALIGN(size, blkbits) ALIGN((size), (1 << (blkbits))) #define EXT4_BLOCK_ALIGN(size, blkbits) ALIGN((size), (1 << (blkbits)))
/* Translate a block number to a cluster number */
#define EXT4_B2C(sbi, blk) ((blk) >> (sbi)->s_cluster_bits)
/* Translate a cluster number to a block number */
#define EXT4_C2B(sbi, cluster) ((cluster) << (sbi)->s_cluster_bits)
/* Translate # of blks to # of clusters */
#define EXT4_NUM_B2C(sbi, blks) (((blks) + (sbi)->s_cluster_ratio - 1) >> \
(sbi)->s_cluster_bits)
/* /*
* Structure of a blocks group descriptor * Structure of a blocks group descriptor
*/ */
@ -1770,6 +1778,11 @@ extern void ext4_init_block_bitmap(struct super_block *sb,
extern unsigned ext4_free_blocks_after_init(struct super_block *sb, extern unsigned ext4_free_blocks_after_init(struct super_block *sb,
ext4_group_t block_group, ext4_group_t block_group,
struct ext4_group_desc *gdp); struct ext4_group_desc *gdp);
extern unsigned ext4_num_base_meta_clusters(struct super_block *sb,
ext4_group_t block_group);
extern unsigned ext4_num_overhead_clusters(struct super_block *sb,
ext4_group_t block_group,
struct ext4_group_desc *gdp);
ext4_fsblk_t ext4_inode_to_goal_block(struct inode *); ext4_fsblk_t ext4_inode_to_goal_block(struct inode *);
/* dir.c */ /* dir.c */