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ext4_fs.c
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/*
* Copyright (c) 2013 Grzegorz Kostka ([email protected])
*
*
* HelenOS:
* Copyright (c) 2012 Martin Sucha
* Copyright (c) 2012 Frantisek Princ
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/** @addtogroup lwext4
* @{
*/
/**
* @file ext4_fs.c
* @brief More complex filesystem functions.
*/
#include <ext4_config.h>
#include <ext4_types.h>
#include <ext4_misc.h>
#include <ext4_errno.h>
#include <ext4_debug.h>
#include <ext4_trans.h>
#include <ext4_fs.h>
#include <ext4_blockdev.h>
#include <ext4_super.h>
#include <ext4_crc32.h>
#include <ext4_block_group.h>
#include <ext4_balloc.h>
#include <ext4_bitmap.h>
#include <ext4_inode.h>
#include <ext4_ialloc.h>
#include <ext4_extent.h>
#include <string.h>
int ext4_fs_init(struct ext4_fs *fs, struct ext4_blockdev *bdev,
bool read_only)
{
int r, i;
uint16_t tmp;
uint32_t bsize;
ext4_assert(fs && bdev);
fs->bdev = bdev;
fs->read_only = read_only;
r = ext4_sb_read(fs->bdev, &fs->sb);
if (r != EOK)
return r;
if (!ext4_sb_check(&fs->sb))
return ENOTSUP;
bsize = ext4_sb_get_block_size(&fs->sb);
if (bsize > EXT4_MAX_BLOCK_SIZE)
return ENXIO;
r = ext4_fs_check_features(fs, &read_only);
if (r != EOK)
return r;
if (read_only)
fs->read_only = read_only;
/* Compute limits for indirect block levels */
uint32_t blocks_id = bsize / sizeof(uint32_t);
fs->inode_block_limits[0] = EXT4_INODE_DIRECT_BLOCK_COUNT;
fs->inode_blocks_per_level[0] = 1;
for (i = 1; i < 4; i++) {
fs->inode_blocks_per_level[i] =
fs->inode_blocks_per_level[i - 1] * blocks_id;
fs->inode_block_limits[i] = fs->inode_block_limits[i - 1] +
fs->inode_blocks_per_level[i];
}
/*Validate FS*/
tmp = ext4_get16(&fs->sb, state);
if (tmp & EXT4_SUPERBLOCK_STATE_ERROR_FS)
ext4_dbg(DEBUG_FS, DBG_WARN
"last umount error: superblock fs_error flag\n");
if (!fs->read_only) {
/* Mark system as mounted */
ext4_set16(&fs->sb, state, EXT4_SUPERBLOCK_STATE_ERROR_FS);
r = ext4_sb_write(fs->bdev, &fs->sb);
if (r != EOK)
return r;
/*Update mount count*/
ext4_set16(&fs->sb, mount_count, ext4_get16(&fs->sb, mount_count) + 1);
}
return r;
}
int ext4_fs_fini(struct ext4_fs *fs)
{
ext4_assert(fs);
/*Set superblock state*/
ext4_set16(&fs->sb, state, EXT4_SUPERBLOCK_STATE_VALID_FS);
if (!fs->read_only)
return ext4_sb_write(fs->bdev, &fs->sb);
return EOK;
}
static void ext4_fs_debug_features_inc(uint32_t features_incompatible)
{
if (features_incompatible & EXT4_FINCOM_COMPRESSION)
ext4_dbg(DEBUG_FS, DBG_NONE "compression\n");
if (features_incompatible & EXT4_FINCOM_FILETYPE)
ext4_dbg(DEBUG_FS, DBG_NONE "filetype\n");
if (features_incompatible & EXT4_FINCOM_RECOVER)
ext4_dbg(DEBUG_FS, DBG_NONE "recover\n");
if (features_incompatible & EXT4_FINCOM_JOURNAL_DEV)
ext4_dbg(DEBUG_FS, DBG_NONE "journal_dev\n");
if (features_incompatible & EXT4_FINCOM_META_BG)
ext4_dbg(DEBUG_FS, DBG_NONE "meta_bg\n");
if (features_incompatible & EXT4_FINCOM_EXTENTS)
ext4_dbg(DEBUG_FS, DBG_NONE "extents\n");
if (features_incompatible & EXT4_FINCOM_64BIT)
ext4_dbg(DEBUG_FS, DBG_NONE "64bit\n");
if (features_incompatible & EXT4_FINCOM_MMP)
ext4_dbg(DEBUG_FS, DBG_NONE "mnp\n");
if (features_incompatible & EXT4_FINCOM_FLEX_BG)
ext4_dbg(DEBUG_FS, DBG_NONE "flex_bg\n");
if (features_incompatible & EXT4_FINCOM_EA_INODE)
ext4_dbg(DEBUG_FS, DBG_NONE "ea_inode\n");
if (features_incompatible & EXT4_FINCOM_DIRDATA)
ext4_dbg(DEBUG_FS, DBG_NONE "dirdata\n");
if (features_incompatible & EXT4_FINCOM_BG_USE_META_CSUM)
ext4_dbg(DEBUG_FS, DBG_NONE "meta_csum\n");
if (features_incompatible & EXT4_FINCOM_LARGEDIR)
ext4_dbg(DEBUG_FS, DBG_NONE "largedir\n");
if (features_incompatible & EXT4_FINCOM_INLINE_DATA)
ext4_dbg(DEBUG_FS, DBG_NONE "inline_data\n");
}
static void ext4_fs_debug_features_comp(uint32_t features_compatible)
{
if (features_compatible & EXT4_FCOM_DIR_PREALLOC)
ext4_dbg(DEBUG_FS, DBG_NONE "dir_prealloc\n");
if (features_compatible & EXT4_FCOM_IMAGIC_INODES)
ext4_dbg(DEBUG_FS, DBG_NONE "imagic_inodes\n");
if (features_compatible & EXT4_FCOM_HAS_JOURNAL)
ext4_dbg(DEBUG_FS, DBG_NONE "has_journal\n");
if (features_compatible & EXT4_FCOM_EXT_ATTR)
ext4_dbg(DEBUG_FS, DBG_NONE "ext_attr\n");
if (features_compatible & EXT4_FCOM_RESIZE_INODE)
ext4_dbg(DEBUG_FS, DBG_NONE "resize_inode\n");
if (features_compatible & EXT4_FCOM_DIR_INDEX)
ext4_dbg(DEBUG_FS, DBG_NONE "dir_index\n");
}
static void ext4_fs_debug_features_ro(uint32_t features_ro)
{
if (features_ro & EXT4_FRO_COM_SPARSE_SUPER)
ext4_dbg(DEBUG_FS, DBG_NONE "sparse_super\n");
if (features_ro & EXT4_FRO_COM_LARGE_FILE)
ext4_dbg(DEBUG_FS, DBG_NONE "large_file\n");
if (features_ro & EXT4_FRO_COM_BTREE_DIR)
ext4_dbg(DEBUG_FS, DBG_NONE "btree_dir\n");
if (features_ro & EXT4_FRO_COM_HUGE_FILE)
ext4_dbg(DEBUG_FS, DBG_NONE "huge_file\n");
if (features_ro & EXT4_FRO_COM_GDT_CSUM)
ext4_dbg(DEBUG_FS, DBG_NONE "gtd_csum\n");
if (features_ro & EXT4_FRO_COM_DIR_NLINK)
ext4_dbg(DEBUG_FS, DBG_NONE "dir_nlink\n");
if (features_ro & EXT4_FRO_COM_EXTRA_ISIZE)
ext4_dbg(DEBUG_FS, DBG_NONE "extra_isize\n");
if (features_ro & EXT4_FRO_COM_QUOTA)
ext4_dbg(DEBUG_FS, DBG_NONE "quota\n");
if (features_ro & EXT4_FRO_COM_BIGALLOC)
ext4_dbg(DEBUG_FS, DBG_NONE "bigalloc\n");
if (features_ro & EXT4_FRO_COM_METADATA_CSUM)
ext4_dbg(DEBUG_FS, DBG_NONE "metadata_csum\n");
}
int ext4_fs_check_features(struct ext4_fs *fs, bool *read_only)
{
ext4_assert(fs && read_only);
uint32_t v;
if (ext4_get32(&fs->sb, rev_level) == 0) {
*read_only = false;
return EOK;
}
ext4_dbg(DEBUG_FS, DBG_INFO "sblock features_incompatible:\n");
ext4_fs_debug_features_inc(ext4_get32(&fs->sb, features_incompatible));
ext4_dbg(DEBUG_FS, DBG_INFO "sblock features_compatible:\n");
ext4_fs_debug_features_comp(ext4_get32(&fs->sb, features_compatible));
ext4_dbg(DEBUG_FS, DBG_INFO "sblock features_read_only:\n");
ext4_fs_debug_features_ro(ext4_get32(&fs->sb, features_read_only));
/*Check features_incompatible*/
v = (ext4_get32(&fs->sb, features_incompatible) &
(~CONFIG_SUPPORTED_FINCOM));
if (v) {
ext4_dbg(DEBUG_FS, DBG_ERROR
"sblock has unsupported features incompatible:\n");
ext4_fs_debug_features_inc(v);
return ENOTSUP;
}
/*Check features_read_only*/
v = ext4_get32(&fs->sb, features_read_only);
v &= ~CONFIG_SUPPORTED_FRO_COM;
if (v) {
ext4_dbg(DEBUG_FS, DBG_WARN
"sblock has unsupported features read only:\n");
ext4_fs_debug_features_ro(v);
*read_only = true;
return EOK;
}
*read_only = false;
return EOK;
}
/**@brief Determine whether the block is inside the group.
* @param baddr block address
* @param bgid block group id
* @return Error code
*/
static bool ext4_block_in_group(struct ext4_sblock *s, ext4_fsblk_t baddr,
uint32_t bgid)
{
uint32_t actual_bgid;
actual_bgid = ext4_balloc_get_bgid_of_block(s, baddr);
if (actual_bgid == bgid)
return true;
return false;
}
/**@brief To avoid calling the atomic setbit hundreds or thousands of times, we only
* need to use it within a single byte (to ensure we get endianness right).
* We can use memset for the rest of the bitmap as there are no other users.
*/
static void ext4_fs_mark_bitmap_end(int start_bit, int end_bit, void *bitmap)
{
int i;
if (start_bit >= end_bit)
return;
for (i = start_bit; (unsigned)i < ((start_bit + 7) & ~7UL); i++)
ext4_bmap_bit_set(bitmap, i);
if (i < end_bit)
memset((char *)bitmap + (i >> 3), 0xff, (end_bit - i) >> 3);
}
/**@brief Initialize block bitmap in block group.
* @param bg_ref Reference to block group
* @return Error code
*/
static int ext4_fs_init_block_bitmap(struct ext4_block_group_ref *bg_ref)
{
struct ext4_sblock *sb = &bg_ref->fs->sb;
struct ext4_bgroup *bg = bg_ref->block_group;
int rc;
uint32_t bit, bit_max;
uint32_t group_blocks;
uint16_t inode_size = ext4_get16(sb, inode_size);
uint32_t block_size = ext4_sb_get_block_size(sb);
uint32_t inodes_per_group = ext4_get32(sb, inodes_per_group);
ext4_fsblk_t i;
ext4_fsblk_t bmp_blk = ext4_bg_get_block_bitmap(bg, sb);
ext4_fsblk_t bmp_inode = ext4_bg_get_inode_bitmap(bg, sb);
ext4_fsblk_t inode_table = ext4_bg_get_inode_table_first_block(bg, sb);
ext4_fsblk_t first_bg = ext4_balloc_get_block_of_bgid(sb, bg_ref->index);
uint32_t dsc_per_block = block_size / ext4_sb_get_desc_size(sb);
bool flex_bg = ext4_sb_feature_incom(sb, EXT4_FINCOM_FLEX_BG);
bool meta_bg = ext4_sb_feature_incom(sb, EXT4_FINCOM_META_BG);
uint32_t inode_table_bcnt = inodes_per_group * inode_size / block_size;
struct ext4_block block_bitmap;
rc = ext4_trans_block_get_noread(bg_ref->fs->bdev, &block_bitmap, bmp_blk);
if (rc != EOK)
return rc;
memset(block_bitmap.data, 0, block_size);
bit_max = ext4_sb_is_super_in_bg(sb, bg_ref->index);
uint32_t count = ext4_sb_first_meta_bg(sb) * dsc_per_block;
if (!meta_bg || bg_ref->index < count) {
if (bit_max) {
bit_max += ext4_bg_num_gdb(sb, bg_ref->index);
bit_max += ext4_get16(sb, s_reserved_gdt_blocks);
}
} else { /* For META_BG_BLOCK_GROUPS */
bit_max += ext4_bg_num_gdb(sb, bg_ref->index);
}
for (bit = 0; bit < bit_max; bit++)
ext4_bmap_bit_set(block_bitmap.data, bit);
if (bg_ref->index == ext4_block_group_cnt(sb) - 1) {
/*
* Even though mke2fs always initialize first and last group
* if some other tool enabled the EXT4_BG_BLOCK_UNINIT we need
* to make sure we calculate the right free blocks
*/
group_blocks = (uint32_t)(ext4_sb_get_blocks_cnt(sb) -
ext4_get32(sb, first_data_block) -
ext4_get32(sb, blocks_per_group) *
(ext4_block_group_cnt(sb) - 1));
} else {
group_blocks = ext4_get32(sb, blocks_per_group);
}
bool in_bg;
in_bg = ext4_block_in_group(sb, bmp_blk, bg_ref->index);
if (!flex_bg || in_bg)
ext4_bmap_bit_set(block_bitmap.data,
(uint32_t)(bmp_blk - first_bg));
in_bg = ext4_block_in_group(sb, bmp_inode, bg_ref->index);
if (!flex_bg || in_bg)
ext4_bmap_bit_set(block_bitmap.data,
(uint32_t)(bmp_inode - first_bg));
for (i = inode_table; i < inode_table + inode_table_bcnt; i++) {
in_bg = ext4_block_in_group(sb, i, bg_ref->index);
if (!flex_bg || in_bg)
ext4_bmap_bit_set(block_bitmap.data,
(uint32_t)(i - first_bg));
}
/*
* Also if the number of blocks within the group is
* less than the blocksize * 8 ( which is the size
* of bitmap ), set rest of the block bitmap to 1
*/
ext4_fs_mark_bitmap_end(group_blocks, block_size * 8, block_bitmap.data);
ext4_trans_set_block_dirty(block_bitmap.buf);
ext4_balloc_set_bitmap_csum(sb, bg_ref->block_group, block_bitmap.data);
bg_ref->dirty = true;
/* Save bitmap */
return ext4_block_set(bg_ref->fs->bdev, &block_bitmap);
}
/**@brief Initialize i-node bitmap in block group.
* @param bg_ref Reference to block group
* @return Error code
*/
static int ext4_fs_init_inode_bitmap(struct ext4_block_group_ref *bg_ref)
{
int rc;
struct ext4_sblock *sb = &bg_ref->fs->sb;
struct ext4_bgroup *bg = bg_ref->block_group;
/* Load bitmap */
ext4_fsblk_t bitmap_block_addr = ext4_bg_get_inode_bitmap(bg, sb);
struct ext4_block b;
rc = ext4_trans_block_get_noread(bg_ref->fs->bdev, &b, bitmap_block_addr);
if (rc != EOK)
return rc;
/* Initialize all bitmap bits to zero */
uint32_t block_size = ext4_sb_get_block_size(sb);
uint32_t inodes_per_group = ext4_get32(sb, inodes_per_group);
memset(b.data, 0, (inodes_per_group + 7) / 8);
uint32_t start_bit = inodes_per_group;
uint32_t end_bit = block_size * 8;
uint32_t i;
for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++)
ext4_bmap_bit_set(b.data, i);
if (i < end_bit)
memset(b.data + (i >> 3), 0xff, (end_bit - i) >> 3);
ext4_trans_set_block_dirty(b.buf);
ext4_ialloc_set_bitmap_csum(sb, bg, b.data);
bg_ref->dirty = true;
/* Save bitmap */
return ext4_block_set(bg_ref->fs->bdev, &b);
}
/**@brief Initialize i-node table in block group.
* @param bg_ref Reference to block group
* @return Error code
*/
static int ext4_fs_init_inode_table(struct ext4_block_group_ref *bg_ref)
{
struct ext4_sblock *sb = &bg_ref->fs->sb;
struct ext4_bgroup *bg = bg_ref->block_group;
uint32_t inode_size = ext4_get16(sb, inode_size);
uint32_t block_size = ext4_sb_get_block_size(sb);
uint32_t inodes_per_block = block_size / inode_size;
uint32_t inodes_in_group = ext4_inodes_in_group_cnt(sb, bg_ref->index);
uint32_t table_blocks = inodes_in_group / inodes_per_block;
ext4_fsblk_t fblock;
if (inodes_in_group % inodes_per_block)
table_blocks++;
/* Compute initialization bounds */
ext4_fsblk_t first_block = ext4_bg_get_inode_table_first_block(bg, sb);
ext4_fsblk_t last_block = first_block + table_blocks - 1;
/* Initialization of all itable blocks */
for (fblock = first_block; fblock <= last_block; ++fblock) {
struct ext4_block b;
int rc = ext4_trans_block_get_noread(bg_ref->fs->bdev, &b, fblock);
if (rc != EOK)
return rc;
memset(b.data, 0, block_size);
ext4_trans_set_block_dirty(b.buf);
rc = ext4_block_set(bg_ref->fs->bdev, &b);
if (rc != EOK)
return rc;
}
return EOK;
}
static ext4_fsblk_t ext4_fs_get_descriptor_block(struct ext4_sblock *s,
uint32_t bgid,
uint32_t dsc_per_block)
{
uint32_t first_meta_bg, dsc_id;
int has_super = 0;
dsc_id = bgid / dsc_per_block;
first_meta_bg = ext4_sb_first_meta_bg(s);
bool meta_bg = ext4_sb_feature_incom(s, EXT4_FINCOM_META_BG);
if (!meta_bg || dsc_id < first_meta_bg)
return ext4_get32(s, first_data_block) + dsc_id + 1;
if (ext4_sb_is_super_in_bg(s, bgid))
has_super = 1;
return (has_super + ext4_fs_first_bg_block_no(s, bgid));
}
/**@brief Compute checksum of block group descriptor.
* @param sb Superblock
* @param bgid Index of block group in the filesystem
* @param bg Block group to compute checksum for
* @return Checksum value
*/
static uint16_t ext4_fs_bg_checksum(struct ext4_sblock *sb, uint32_t bgid,
struct ext4_bgroup *bg)
{
/* If checksum not supported, 0 will be returned */
uint16_t crc = 0;
#if CONFIG_META_CSUM_ENABLE
/* Compute the checksum only if the filesystem supports it */
if (ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM)) {
/* Use metadata_csum algorithm instead */
uint32_t le32_bgid = to_le32(bgid);
uint32_t orig_checksum, checksum;
/* Preparation: temporarily set bg checksum to 0 */
orig_checksum = bg->checksum;
bg->checksum = 0;
/* First calculate crc32 checksum against fs uuid */
checksum = ext4_crc32c(EXT4_CRC32_INIT, sb->uuid,
sizeof(sb->uuid));
/* Then calculate crc32 checksum against bgid */
checksum = ext4_crc32c(checksum, &le32_bgid, sizeof(bgid));
/* Finally calculate crc32 checksum against block_group_desc */
checksum = ext4_crc32c(checksum, bg, ext4_sb_get_desc_size(sb));
bg->checksum = orig_checksum;
crc = checksum & 0xFFFF;
return crc;
}
#endif
if (ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_GDT_CSUM)) {
uint8_t *base = (uint8_t *)bg;
uint8_t *checksum = (uint8_t *)&bg->checksum;
uint32_t offset = (uint32_t)(checksum - base);
/* Convert block group index to little endian */
uint32_t group = to_le32(bgid);
/* Initialization */
crc = ext4_bg_crc16(~0, sb->uuid, sizeof(sb->uuid));
/* Include index of block group */
crc = ext4_bg_crc16(crc, (uint8_t *)&group, sizeof(group));
/* Compute crc from the first part (stop before checksum field)
*/
crc = ext4_bg_crc16(crc, (uint8_t *)bg, offset);
/* Skip checksum */
offset += sizeof(bg->checksum);
/* Checksum of the rest of block group descriptor */
if ((ext4_sb_feature_incom(sb, EXT4_FINCOM_64BIT)) &&
(offset < ext4_sb_get_desc_size(sb))) {
const uint8_t *start = ((uint8_t *)bg) + offset;
size_t len = ext4_sb_get_desc_size(sb) - offset;
crc = ext4_bg_crc16(crc, start, len);
}
}
return crc;
}
#if CONFIG_META_CSUM_ENABLE
static bool ext4_fs_verify_bg_csum(struct ext4_sblock *sb,
uint32_t bgid,
struct ext4_bgroup *bg)
{
if (!ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM))
return true;
return ext4_fs_bg_checksum(sb, bgid, bg) == to_le16(bg->checksum);
}
#else
#define ext4_fs_verify_bg_csum(...) true
#endif
int ext4_fs_get_block_group_ref(struct ext4_fs *fs, uint32_t bgid,
struct ext4_block_group_ref *ref)
{
/* Compute number of descriptors, that fits in one data block */
uint32_t block_size = ext4_sb_get_block_size(&fs->sb);
uint32_t dsc_cnt = block_size / ext4_sb_get_desc_size(&fs->sb);
/* Block group descriptor table starts at the next block after
* superblock */
uint64_t block_id = ext4_fs_get_descriptor_block(&fs->sb, bgid, dsc_cnt);
uint32_t offset = (bgid % dsc_cnt) * ext4_sb_get_desc_size(&fs->sb);
int rc = ext4_trans_block_get(fs->bdev, &ref->block, block_id);
if (rc != EOK)
return rc;
ref->block_group = (void *)(ref->block.data + offset);
ref->fs = fs;
ref->index = bgid;
ref->dirty = false;
struct ext4_bgroup *bg = ref->block_group;
if (!ext4_fs_verify_bg_csum(&fs->sb, bgid, bg)) {
ext4_dbg(DEBUG_FS,
DBG_WARN "Block group descriptor checksum failed."
"Block group index: %" PRIu32"\n",
bgid);
}
if (ext4_bg_has_flag(bg, EXT4_BLOCK_GROUP_BLOCK_UNINIT)) {
rc = ext4_fs_init_block_bitmap(ref);
if (rc != EOK) {
ext4_block_set(fs->bdev, &ref->block);
return rc;
}
ext4_bg_clear_flag(bg, EXT4_BLOCK_GROUP_BLOCK_UNINIT);
ref->dirty = true;
}
if (ext4_bg_has_flag(bg, EXT4_BLOCK_GROUP_INODE_UNINIT)) {
rc = ext4_fs_init_inode_bitmap(ref);
if (rc != EOK) {
ext4_block_set(ref->fs->bdev, &ref->block);
return rc;
}
ext4_bg_clear_flag(bg, EXT4_BLOCK_GROUP_INODE_UNINIT);
if (!ext4_bg_has_flag(bg, EXT4_BLOCK_GROUP_ITABLE_ZEROED)) {
rc = ext4_fs_init_inode_table(ref);
if (rc != EOK) {
ext4_block_set(fs->bdev, &ref->block);
return rc;
}
ext4_bg_set_flag(bg, EXT4_BLOCK_GROUP_ITABLE_ZEROED);
}
ref->dirty = true;
}
return EOK;
}
int ext4_fs_put_block_group_ref(struct ext4_block_group_ref *ref)
{
/* Check if reference modified */
if (ref->dirty) {
/* Compute new checksum of block group */
uint16_t cs;
cs = ext4_fs_bg_checksum(&ref->fs->sb, ref->index,
ref->block_group);
ref->block_group->checksum = to_le16(cs);
/* Mark block dirty for writing changes to physical device */
ext4_trans_set_block_dirty(ref->block.buf);
}
/* Put back block, that contains block group descriptor */
return ext4_block_set(ref->fs->bdev, &ref->block);
}
#if CONFIG_META_CSUM_ENABLE
static uint32_t ext4_fs_inode_checksum(struct ext4_inode_ref *inode_ref)
{
uint32_t checksum = 0;
struct ext4_sblock *sb = &inode_ref->fs->sb;
uint16_t inode_size = ext4_get16(sb, inode_size);
if (ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM)) {
uint32_t orig_checksum;
uint32_t ino_index = to_le32(inode_ref->index);
uint32_t ino_gen =
to_le32(ext4_inode_get_generation(inode_ref->inode));
/* Preparation: temporarily set bg checksum to 0 */
orig_checksum = ext4_inode_get_csum(sb, inode_ref->inode);
ext4_inode_set_csum(sb, inode_ref->inode, 0);
/* First calculate crc32 checksum against fs uuid */
checksum = ext4_crc32c(EXT4_CRC32_INIT, sb->uuid,
sizeof(sb->uuid));
/* Then calculate crc32 checksum against inode number
* and inode generation */
checksum = ext4_crc32c(checksum, &ino_index, sizeof(ino_index));
checksum = ext4_crc32c(checksum, &ino_gen, sizeof(ino_gen));
/* Finally calculate crc32 checksum against
* the entire inode */
checksum = ext4_crc32c(checksum, inode_ref->inode, inode_size);
ext4_inode_set_csum(sb, inode_ref->inode, orig_checksum);
/* If inode size is not large enough to hold the
* upper 16bit of the checksum */
if (inode_size == EXT4_GOOD_OLD_INODE_SIZE)
checksum &= 0xFFFF;
}
return checksum;
}
#else
#define ext4_fs_inode_checksum(...) 0
#endif
static void ext4_fs_set_inode_checksum(struct ext4_inode_ref *inode_ref)
{
struct ext4_sblock *sb = &inode_ref->fs->sb;
if (!ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM))
return;
uint32_t csum = ext4_fs_inode_checksum(inode_ref);
ext4_inode_set_csum(sb, inode_ref->inode, csum);
}
#if CONFIG_META_CSUM_ENABLE
static bool ext4_fs_verify_inode_csum(struct ext4_inode_ref *inode_ref)
{
struct ext4_sblock *sb = &inode_ref->fs->sb;
if (!ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM))
return true;
return ext4_inode_get_csum(sb, inode_ref->inode) ==
ext4_fs_inode_checksum(inode_ref);
}
#else
#define ext4_fs_verify_inode_csum(...) true
#endif
static int
__ext4_fs_get_inode_ref(struct ext4_fs *fs, uint32_t index,
struct ext4_inode_ref *ref,
bool initialized)
{
/* Compute number of i-nodes, that fits in one data block */
uint32_t inodes_per_group = ext4_get32(&fs->sb, inodes_per_group);
/*
* Inode numbers are 1-based, but it is simpler to work with 0-based
* when computing indices
*/
index -= 1;
uint32_t block_group = index / inodes_per_group;
uint32_t offset_in_group = index % inodes_per_group;
/* Load block group, where i-node is located */
struct ext4_block_group_ref bg_ref;
int rc = ext4_fs_get_block_group_ref(fs, block_group, &bg_ref);
if (rc != EOK) {
return rc;
}
/* Load block address, where i-node table is located */
ext4_fsblk_t inode_table_start =
ext4_bg_get_inode_table_first_block(bg_ref.block_group, &fs->sb);
/* Put back block group reference (not needed more) */
rc = ext4_fs_put_block_group_ref(&bg_ref);
if (rc != EOK) {
return rc;
}
/* Compute position of i-node in the block group */
uint16_t inode_size = ext4_get16(&fs->sb, inode_size);
uint32_t block_size = ext4_sb_get_block_size(&fs->sb);
uint32_t byte_offset_in_group = offset_in_group * inode_size;
/* Compute block address */
ext4_fsblk_t block_id =
inode_table_start + (byte_offset_in_group / block_size);
rc = ext4_trans_block_get(fs->bdev, &ref->block, block_id);
if (rc != EOK) {
return rc;
}
/* Compute position of i-node in the data block */
uint32_t offset_in_block = byte_offset_in_group % block_size;
ref->inode = (struct ext4_inode *)(ref->block.data + offset_in_block);
/* We need to store the original value of index in the reference */
ref->index = index + 1;
ref->fs = fs;
ref->dirty = false;
if (initialized && !ext4_fs_verify_inode_csum(ref)) {
ext4_dbg(DEBUG_FS,
DBG_WARN "Inode checksum failed."
"Inode: %" PRIu32"\n",
ref->index);
}
return EOK;
}
int ext4_fs_get_inode_ref(struct ext4_fs *fs, uint32_t index,
struct ext4_inode_ref *ref)
{
return __ext4_fs_get_inode_ref(fs, index, ref, true);
}
int ext4_fs_put_inode_ref(struct ext4_inode_ref *ref)
{
/* Check if reference modified */
if (ref->dirty) {
/* Mark block dirty for writing changes to physical device */
ext4_fs_set_inode_checksum(ref);
ext4_trans_set_block_dirty(ref->block.buf);
}
/* Put back block, that contains i-node */
return ext4_block_set(ref->fs->bdev, &ref->block);
}
void ext4_fs_inode_blocks_init(struct ext4_fs *fs,
struct ext4_inode_ref *inode_ref)
{
struct ext4_inode *inode = inode_ref->inode;
/* Reset blocks array. For inode which is not directory or file, just
* fill in blocks with 0 */
switch (ext4_inode_type(&fs->sb, inode_ref->inode)) {
case EXT4_INODE_MODE_FILE:
case EXT4_INODE_MODE_DIRECTORY:
break;
default:
return;
}
#if CONFIG_EXTENT_ENABLE && CONFIG_EXTENTS_ENABLE
/* Initialize extents if needed */
if (ext4_sb_feature_incom(&fs->sb, EXT4_FINCOM_EXTENTS)) {
ext4_inode_set_flag(inode, EXT4_INODE_FLAG_EXTENTS);
/* Initialize extent root header */
ext4_extent_tree_init(inode_ref);
}
inode_ref->dirty = true;
#endif
}
uint32_t ext4_fs_correspond_inode_mode(int filetype)
{
switch (filetype) {
case EXT4_DE_DIR:
return EXT4_INODE_MODE_DIRECTORY;
case EXT4_DE_REG_FILE:
return EXT4_INODE_MODE_FILE;
case EXT4_DE_SYMLINK:
return EXT4_INODE_MODE_SOFTLINK;
case EXT4_DE_CHRDEV:
return EXT4_INODE_MODE_CHARDEV;
case EXT4_DE_BLKDEV:
return EXT4_INODE_MODE_BLOCKDEV;
case EXT4_DE_FIFO:
return EXT4_INODE_MODE_FIFO;
case EXT4_DE_SOCK:
return EXT4_INODE_MODE_SOCKET;
}
/* FIXME: unsupported filetype */
return EXT4_INODE_MODE_FILE;
}
int ext4_fs_alloc_inode(struct ext4_fs *fs, struct ext4_inode_ref *inode_ref,
int filetype)
{
/* Check if newly allocated i-node will be a directory */
bool is_dir;
uint16_t inode_size = ext4_get16(&fs->sb, inode_size);
is_dir = (filetype == EXT4_DE_DIR);
/* Allocate inode by allocation algorithm */
uint32_t index;
int rc = ext4_ialloc_alloc_inode(fs, &index, is_dir);
if (rc != EOK)
return rc;
/* Load i-node from on-disk i-node table */
rc = __ext4_fs_get_inode_ref(fs, index, inode_ref, false);
if (rc != EOK) {
ext4_ialloc_free_inode(fs, index, is_dir);
return rc;
}
/* Initialize i-node */
struct ext4_inode *inode = inode_ref->inode;
memset(inode, 0, inode_size);
uint32_t mode;
if (is_dir) {
/*
* Default directory permissions to be compatible with other
* systems
* 0777 (octal) == rwxrwxrwx
*/
mode = 0777;
mode |= EXT4_INODE_MODE_DIRECTORY;
} else if (filetype == EXT4_DE_SYMLINK) {
/*
* Default symbolic link permissions to be compatible with other systems
* 0777 (octal) == rwxrwxrwx
*/
mode = 0777;
mode |= EXT4_INODE_MODE_SOFTLINK;
} else {
/*
* Default file permissions to be compatible with other systems
* 0666 (octal) == rw-rw-rw-
*/
mode = 0666;
mode |= ext4_fs_correspond_inode_mode(filetype);
}
ext4_inode_set_mode(&fs->sb, inode, mode);
ext4_inode_set_links_cnt(inode, 0);
ext4_inode_set_uid(inode, 0);
ext4_inode_set_gid(inode, 0);
ext4_inode_set_size(inode, 0);
ext4_inode_set_access_time(inode, 0);
ext4_inode_set_change_inode_time(inode, 0);
ext4_inode_set_modif_time(inode, 0);
ext4_inode_set_del_time(inode, 0);
ext4_inode_set_blocks_count(&fs->sb, inode, 0);
ext4_inode_set_flags(inode, 0);
ext4_inode_set_generation(inode, 0);
if (inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
uint16_t size = ext4_get16(&fs->sb, want_extra_isize);
ext4_inode_set_extra_isize(&fs->sb, inode, size);
}
memset(inode->blocks, 0, sizeof(inode->blocks));
inode_ref->dirty = true;
return EOK;
}
int ext4_fs_free_inode(struct ext4_inode_ref *inode_ref)
{
struct ext4_fs *fs = inode_ref->fs;
uint32_t offset;
uint32_t suboff;
int rc;
#if CONFIG_EXTENT_ENABLE && CONFIG_EXTENTS_ENABLE
/* For extents must be data block destroyed by other way */
if ((ext4_sb_feature_incom(&fs->sb, EXT4_FINCOM_EXTENTS)) &&
(ext4_inode_has_flag(inode_ref->inode, EXT4_INODE_FLAG_EXTENTS))) {
/* Data structures are released during truncate operation... */
goto finish;
}
#endif
/* Release all indirect (no data) blocks */
/* 1) Single indirect */
ext4_fsblk_t fblock = ext4_inode_get_indirect_block(inode_ref->inode, 0);
if (fblock != 0) {
int rc = ext4_balloc_free_block(inode_ref, fblock);
if (rc != EOK)
return rc;
ext4_inode_set_indirect_block(inode_ref->inode, 0, 0);
}
uint32_t block_size = ext4_sb_get_block_size(&fs->sb);
uint32_t count = block_size / sizeof(uint32_t);
struct ext4_block block;
/* 2) Double indirect */
fblock = ext4_inode_get_indirect_block(inode_ref->inode, 1);
if (fblock != 0) {
int rc = ext4_trans_block_get(fs->bdev, &block, fblock);
if (rc != EOK)
return rc;
ext4_fsblk_t ind_block;
for (offset = 0; offset < count; ++offset) {
ind_block = to_le32(((uint32_t *)block.data)[offset]);
if (ind_block == 0)
continue;
rc = ext4_balloc_free_block(inode_ref, ind_block);
if (rc != EOK) {
ext4_block_set(fs->bdev, &block);
return rc;
}
}
ext4_block_set(fs->bdev, &block);
rc = ext4_balloc_free_block(inode_ref, fblock);
if (rc != EOK)
return rc;
ext4_inode_set_indirect_block(inode_ref->inode, 1, 0);
}
/* 3) Tripple indirect */
struct ext4_block subblock;
fblock = ext4_inode_get_indirect_block(inode_ref->inode, 2);
if (fblock == 0)
goto finish;
rc = ext4_trans_block_get(fs->bdev, &block, fblock);
if (rc != EOK)
return rc;