* @brief Superblock operations.
*/
-#include <ext4_config.h>
-#include <ext4_super.h>
-
+#include "ext4_config.h"
+#include "ext4_super.h"
+#include "ext4_crc32c.h"
uint32_t ext4_block_group_cnt(struct ext4_sblock *s)
{
- uint64_t blocks_count = ext4_sb_get_blocks_cnt(s);
- uint32_t blocks_per_group = ext4_get32(s, blocks_per_group);
+ uint64_t blocks_count = ext4_sb_get_blocks_cnt(s);
+ uint32_t blocks_per_group = ext4_get32(s, blocks_per_group);
- uint32_t block_groups_count = blocks_count / blocks_per_group;
+ uint32_t block_groups_count = blocks_count / blocks_per_group;
- if (blocks_count % blocks_per_group)
- block_groups_count++;
+ if (blocks_count % blocks_per_group)
+ block_groups_count++;
- return block_groups_count;
+ return block_groups_count;
}
uint32_t ext4_blocks_in_group_cnt(struct ext4_sblock *s, uint32_t bgid)
{
- uint32_t block_group_count = ext4_block_group_cnt(s);
- uint32_t blocks_per_group = ext4_get32(s, blocks_per_group);
- uint64_t total_blocks = ext4_sb_get_blocks_cnt(s);
-
- if (bgid < block_group_count - 1)
- return blocks_per_group;
+ uint32_t block_group_count = ext4_block_group_cnt(s);
+ uint32_t blocks_per_group = ext4_get32(s, blocks_per_group);
+ uint64_t total_blocks = ext4_sb_get_blocks_cnt(s);
+ if (bgid < block_group_count - 1)
+ return blocks_per_group;
- return (total_blocks - ((block_group_count - 1) * blocks_per_group));
+ return (total_blocks - ((block_group_count - 1) * blocks_per_group));
}
uint32_t ext4_inodes_in_group_cnt(struct ext4_sblock *s, uint32_t bgid)
{
- uint32_t block_group_count = ext4_block_group_cnt(s);
- uint32_t inodes_per_group = ext4_get32(s, inodes_per_group);
- uint32_t total_inodes = ext4_get32(s, inodes_count);
+ uint32_t block_group_count = ext4_block_group_cnt(s);
+ uint32_t inodes_per_group = ext4_get32(s, inodes_per_group);
+ uint32_t total_inodes = ext4_get32(s, inodes_count);
+ if (bgid < block_group_count - 1)
+ return inodes_per_group;
- if (bgid < block_group_count - 1)
- return inodes_per_group;
+ return (total_inodes - ((block_group_count - 1) * inodes_per_group));
+}
+
+#if CONFIG_META_CSUM_ENABLE
+static uint32_t ext4_sb_csum(struct ext4_sblock *s)
+{
- return (total_inodes - ((block_group_count - 1) * inodes_per_group));
+ return ext4_crc32c(EXT4_CRC32_INIT, s,
+ offsetof(struct ext4_sblock, checksum));
+}
+#else
+#define ext4_sb_csum(...) 0
+#endif
+
+static bool ext4_sb_verify_csum(struct ext4_sblock *s)
+{
+ if (!ext4_sb_feature_ro_com(s, EXT4_FRO_COM_METADATA_CSUM))
+ return true;
+
+ if (s->checksum_type != to_le32(EXT4_CHECKSUM_CRC32C))
+ return false;
+
+ return s->checksum == to_le32(ext4_sb_csum(s));
+}
+
+static void ext4_sb_set_csum(struct ext4_sblock *s)
+{
+ if (!ext4_sb_feature_ro_com(s, EXT4_FRO_COM_METADATA_CSUM))
+ return;
+
+ s->checksum = to_le32(ext4_sb_csum(s));
}
int ext4_sb_write(struct ext4_blockdev *bdev, struct ext4_sblock *s)
{
- return ext4_block_writebytes(bdev, EXT4_SUPERBLOCK_OFFSET,
- s, EXT4_SUPERBLOCK_SIZE);
+ ext4_sb_set_csum(s);
+ return ext4_block_writebytes(bdev, EXT4_SUPERBLOCK_OFFSET, s,
+ EXT4_SUPERBLOCK_SIZE);
}
int ext4_sb_read(struct ext4_blockdev *bdev, struct ext4_sblock *s)
{
- return ext4_block_readbytes(bdev, EXT4_SUPERBLOCK_OFFSET,
- s, EXT4_SUPERBLOCK_SIZE);
+ return ext4_block_readbytes(bdev, EXT4_SUPERBLOCK_OFFSET, s,
+ EXT4_SUPERBLOCK_SIZE);
}
bool ext4_sb_check(struct ext4_sblock *s)
{
- if (ext4_get16(s, magic) != EXT4_SUPERBLOCK_MAGIC)
- return false;
+ if (ext4_get16(s, magic) != EXT4_SUPERBLOCK_MAGIC)
+ return false;
+
+ if (ext4_get32(s, inodes_count) == 0)
+ return false;
- if (ext4_get32(s, inodes_count) == 0)
- return false;
+ if (ext4_sb_get_blocks_cnt(s) == 0)
+ return false;
- if (ext4_sb_get_blocks_cnt(s) == 0)
- return false;
+ if (ext4_get32(s, blocks_per_group) == 0)
+ return false;
- if (ext4_get32(s, blocks_per_group) == 0)
- return false;
+ if (ext4_get32(s, inodes_per_group) == 0)
+ return false;
- if (ext4_get32(s, inodes_per_group) == 0)
- return false;
+ if (ext4_get16(s, inode_size) < 128)
+ return false;
- if (ext4_get16(s, inode_size) < 128)
- return false;
+ if (ext4_get32(s, first_inode) < 11)
+ return false;
- if (ext4_get32(s, first_inode) < 11)
- return false;
+ if (ext4_sb_get_desc_size(s) < EXT4_MIN_BLOCK_GROUP_DESCRIPTOR_SIZE)
+ return false;
- if (ext4_sb_get_desc_size(s) < EXT4_MIN_BLOCK_GROUP_DESCRIPTOR_SIZE)
- return false;
+ if (ext4_sb_get_desc_size(s) > EXT4_MAX_BLOCK_GROUP_DESCRIPTOR_SIZE)
+ return false;
- if (ext4_sb_get_desc_size(s) > EXT4_MAX_BLOCK_GROUP_DESCRIPTOR_SIZE)
- return false;
+ if (!ext4_sb_verify_csum(s))
+ return false;
- return true;
+ return true;
}
-static inline int is_multiple(uint32_t a, uint32_t b)
+static inline int is_power_of(uint32_t a, uint32_t b)
{
- while (1) {
- if (a < b)
- return 0;
- if (a == b)
- return 1;
- if ((a % b) != 0)
- return 0;
- a = a / b;
- }
+ while (1) {
+ if (a < b)
+ return 0;
+ if (a == b)
+ return 1;
+ if ((a % b) != 0)
+ return 0;
+ a = a / b;
+ }
}
-static int ext4_sb_sparse(uint32_t group)
+bool ext4_sb_sparse(uint32_t group)
{
- if (group <= 1)
- return 1;
+ if (group <= 1)
+ return 1;
- if (!(group & 1))
- return 0;
+ if (!(group & 1))
+ return 0;
- return (is_multiple(group, 7) || is_multiple(group, 5) ||
- is_multiple(group, 3));
+ return (is_power_of(group, 7) || is_power_of(group, 5) ||
+ is_power_of(group, 3));
}
-
bool ext4_sb_is_super_in_bg(struct ext4_sblock *s, uint32_t group)
{
- if (ext4_sb_check_read_only(s,
- EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER) &&
- !ext4_sb_sparse(group))
- return false;
- return true;
+ if (ext4_sb_feature_ro_com(s, EXT4_FRO_COM_SPARSE_SUPER) &&
+ !ext4_sb_sparse(group))
+ return false;
+ return true;
+}
+
+static uint32_t ext4_bg_num_gdb_meta(struct ext4_sblock *s, uint32_t group)
+{
+ uint32_t dsc_per_block =
+ ext4_sb_get_block_size(s) / ext4_sb_get_desc_size(s);
+
+ uint32_t metagroup = group / dsc_per_block;
+ uint32_t first = metagroup * dsc_per_block;
+ uint32_t last = first + dsc_per_block - 1;
+
+ if (group == first || group == first + 1 || group == last)
+ return 1;
+ return 0;
}
+static uint32_t ext4_bg_num_gdb_nometa(struct ext4_sblock *s, uint32_t group)
+{
+ if (!ext4_sb_is_super_in_bg(s, group))
+ return 0;
+ uint32_t dsc_per_block =
+ ext4_sb_get_block_size(s) / ext4_sb_get_desc_size(s);
+
+ uint32_t db_count =
+ (ext4_block_group_cnt(s) + dsc_per_block - 1) / dsc_per_block;
+
+ if (ext4_sb_feature_incom(s, EXT4_FINCOM_META_BG))
+ return ext4_sb_first_meta_bg(s);
+
+ return db_count;
+}
+
+uint32_t ext4_bg_num_gdb(struct ext4_sblock *s, uint32_t group)
+{
+ uint32_t dsc_per_block =
+ ext4_sb_get_block_size(s) / ext4_sb_get_desc_size(s);
+ uint32_t first_meta_bg = ext4_sb_first_meta_bg(s);
+ uint32_t metagroup = group / dsc_per_block;
+
+ if (!ext4_sb_feature_incom(s,EXT4_FINCOM_META_BG) ||
+ metagroup < first_meta_bg)
+ return ext4_bg_num_gdb_nometa(s, group);
+
+ return ext4_bg_num_gdb_meta(s, group);
+}
+
+uint32_t ext4_num_base_meta_clusters(struct ext4_sblock *s,
+ uint32_t block_group)
+{
+ uint32_t num;
+ uint32_t dsc_per_block =
+ ext4_sb_get_block_size(s) / ext4_sb_get_desc_size(s);
+
+ num = ext4_sb_is_super_in_bg(s, block_group);
+
+ if (!ext4_sb_feature_incom(s, EXT4_FINCOM_META_BG) ||
+ block_group < ext4_sb_first_meta_bg(s) * dsc_per_block) {
+ if (num) {
+ num += ext4_bg_num_gdb(s, block_group);
+ num += ext4_get16(s, s_reserved_gdt_blocks);
+ }
+ } else {
+ num += ext4_bg_num_gdb(s, block_group);
+ }
+
+ uint32_t clustersize = 1024 << ext4_get32(s, log_cluster_size);
+ uint32_t cluster_ratio = clustersize / ext4_sb_get_block_size(s);
+ uint32_t v =
+ (num + cluster_ratio - 1) >> ext4_get32(s, log_cluster_size);
+
+ return v;
+}
/**
* @}
projects / lwext4.git / blobdiff