ref: ea28608e2cf855d3e8013e9bc18573743ced4ab6
dir: /lwext4/ext4_fs.c/
/*
* Copyright (c) 2013 Grzegorz Kostka (kostka.grzegorz@gmail.com)
*
*
* 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_fs.h>
#include <ext4_errno.h>
#include <ext4_blockdev.h>
#include <ext4_super.h>
#include <ext4_debug.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)
{
int r, i;
uint16_t tmp;
uint32_t bsize;
bool read_only = false;
ext4_assert(fs && bdev);
fs->bdev = bdev;
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)
return ENOTSUP;
/* 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_dprintf(EXT4_DEBUG_FS,
"Filesystem was not cleanly unmounted before \n");
}
/* 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);
return ext4_sb_write(fs->bdev, &fs->sb);
}
static void ext4_fs_debug_features_incomp(uint32_t features_incompatible)
{
if(features_incompatible &
EXT4_FEATURE_INCOMPAT_COMPRESSION){
ext4_dprintf(EXT4_DEBUG_FS, "COMPRESSION\n");
}
if(features_incompatible &
EXT4_FEATURE_INCOMPAT_FILETYPE){
ext4_dprintf(EXT4_DEBUG_FS, "FILETYPE\n");
}
if(features_incompatible &
EXT4_FEATURE_INCOMPAT_RECOVER){
ext4_dprintf(EXT4_DEBUG_FS, "RECOVER\n");
}
if(features_incompatible &
EXT4_FEATURE_INCOMPAT_JOURNAL_DEV){
ext4_dprintf(EXT4_DEBUG_FS,"JOURNAL_DEV\n");
}
if(features_incompatible &
EXT4_FEATURE_INCOMPAT_META_BG){
ext4_dprintf(EXT4_DEBUG_FS, "META_BG\n");
}
if(features_incompatible &
EXT4_FEATURE_INCOMPAT_EXTENTS){
ext4_dprintf(EXT4_DEBUG_FS, "EXTENTS\n");
}
if(features_incompatible &
EXT4_FEATURE_INCOMPAT_64BIT){
ext4_dprintf(EXT4_DEBUG_FS, "64BIT\n");
}
if(features_incompatible &
EXT4_FEATURE_INCOMPAT_MMP){
ext4_dprintf(EXT4_DEBUG_FS, "MMP\n");
}
if(features_incompatible &
EXT4_FEATURE_INCOMPAT_FLEX_BG){
ext4_dprintf(EXT4_DEBUG_FS, "FLEX_BG\n");
}
if(features_incompatible &
EXT4_FEATURE_INCOMPAT_EA_INODE){
ext4_dprintf(EXT4_DEBUG_FS, "EA_INODE\n");
}
if(features_incompatible &
EXT4_FEATURE_INCOMPAT_DIRDATA){
ext4_dprintf(EXT4_DEBUG_FS, "DIRDATA\n");
}
}
static void ext4_fs_debug_features_comp(uint32_t features_compatible)
{
if(features_compatible &
EXT4_FEATURE_COMPAT_DIR_PREALLOC){
ext4_dprintf(EXT4_DEBUG_FS, "DIR_PREALLOC\n");
}
if(features_compatible &
EXT4_FEATURE_COMPAT_IMAGIC_INODES){
ext4_dprintf(EXT4_DEBUG_FS, "IMAGIC_INODES\n");
}
if(features_compatible &
EXT4_FEATURE_COMPAT_HAS_JOURNAL){
ext4_dprintf(EXT4_DEBUG_FS, "HAS_JOURNAL\n");
}
if(features_compatible &
EXT4_FEATURE_COMPAT_EXT_ATTR){
ext4_dprintf(EXT4_DEBUG_FS, "EXT_ATTR\n");
}
if(features_compatible &
EXT4_FEATURE_COMPAT_RESIZE_INODE){
ext4_dprintf(EXT4_DEBUG_FS, "RESIZE_INODE\n");
}
if(features_compatible &
EXT4_FEATURE_COMPAT_DIR_INDEX){
ext4_dprintf(EXT4_DEBUG_FS, "DIR_INDEX\n");
}
}
static void ext4_fs_debug_features_ro(uint32_t features_ro)
{
if(features_ro &
EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER){
ext4_dprintf(EXT4_DEBUG_FS, "SPARSE_SUPER\n");
}
if(features_ro &
EXT4_FEATURE_RO_COMPAT_LARGE_FILE){
ext4_dprintf(EXT4_DEBUG_FS, "LARGE_FILE\n");
}
if(features_ro &
EXT4_FEATURE_RO_COMPAT_BTREE_DIR){
ext4_dprintf(EXT4_DEBUG_FS, "BTREE_DIR\n");
}
if(features_ro &
EXT4_FEATURE_RO_COMPAT_HUGE_FILE){
ext4_dprintf(EXT4_DEBUG_FS, "HUGE_FILE\n");
}
if(features_ro &
EXT4_FEATURE_RO_COMPAT_GDT_CSUM){
ext4_dprintf(EXT4_DEBUG_FS, "GDT_CSUM\n");
}
if(features_ro &
EXT4_FEATURE_RO_COMPAT_DIR_NLINK){
ext4_dprintf(EXT4_DEBUG_FS, "DIR_NLINK\n");
}
if(features_ro &
EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE){
ext4_dprintf(EXT4_DEBUG_FS, "EXTRA_ISIZE\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_dprintf(EXT4_DEBUG_FS,
"\nSblock rev_level: \n%d\n", (int)ext4_get32(&fs->sb, rev_level));
ext4_dprintf(EXT4_DEBUG_FS,
"\nSblock minor_rev_level: \n%d\n",
ext4_get32(&fs->sb, minor_rev_level));
ext4_dprintf(EXT4_DEBUG_FS,
"\nSblock features_incompatible:\n");
ext4_fs_debug_features_incomp(ext4_get32(&fs->sb, features_incompatible));
ext4_dprintf(EXT4_DEBUG_FS,
"\nSblock features_compatible:\n");
ext4_fs_debug_features_comp(ext4_get32(&fs->sb, features_compatible));
ext4_dprintf(EXT4_DEBUG_FS,
"\nSblock 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) &
(~EXT4_FEATURE_INCOMPAT_SUPP));
if (v){
ext4_dprintf(EXT4_DEBUG_FS,
"\nERROR sblock features_incompatible. Unsupported:\n");
ext4_fs_debug_features_incomp(v);
return ENOTSUP;
}
/*Check features_read_only*/
v = (ext4_get32(&fs->sb, features_read_only) &
(~EXT4_FEATURE_RO_COMPAT_SUPP));
if (v){
ext4_dprintf(EXT4_DEBUG_FS,
"\nERROR sblock features_read_only . Unsupported:\n");
ext4_fs_debug_features_incomp(v);
*read_only = true;
return EOK;
}
*read_only = false;
return EOK;
}
uint32_t ext4_fs_baddr2_index_in_group(struct ext4_sblock *s, uint32_t baddr)
{
ext4_assert(baddr);
if(ext4_get32(s, first_data_block))
baddr--;
return baddr % ext4_get32(s, blocks_per_group);
}
uint32_t ext4_fs_index_in_group2_baddr(struct ext4_sblock *s, uint32_t index,
uint32_t bgid)
{
if(ext4_get32(s, first_data_block))
index++;
return ext4_get32(s, blocks_per_group) * bgid + index;
}
/**@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)
{
uint32_t i;
uint32_t bitmap_block_addr = ext4_bg_get_block_bitmap(
bg_ref->block_group, &bg_ref->fs->sb);
struct ext4_block block_bitmap;
int rc = ext4_block_get(bg_ref->fs->bdev, &block_bitmap,
bitmap_block_addr);
if (rc != EOK)
return rc;
memset(block_bitmap.data, 0, ext4_sb_get_block_size(&bg_ref->fs->sb));
/* Determine first block and first data block in group */
uint32_t first_idx = 0;
uint32_t first_data = ext4_balloc_get_first_data_block_in_group(
&bg_ref->fs->sb, bg_ref);
uint32_t first_data_idx = ext4_fs_baddr2_index_in_group(
&bg_ref->fs->sb, first_data);
/*Set bits from to first block to first data block - 1 to one (allocated)*/
/*TODO: Optimize it*/
for (i = first_idx; i < first_data_idx; ++i)
ext4_bmap_bit_set(block_bitmap.data, i);
block_bitmap.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)
{
/* Load bitmap */
uint32_t bitmap_block_addr = ext4_bg_get_inode_bitmap(
bg_ref->block_group, &bg_ref->fs->sb);
struct ext4_block block_bitmap;
int rc = ext4_block_get(bg_ref->fs->bdev, &block_bitmap,
bitmap_block_addr);
if (rc != EOK)
return rc;
/* Initialize all bitmap bits to zero */
uint32_t block_size = ext4_sb_get_block_size(&bg_ref->fs->sb);
uint32_t inodes_per_group = ext4_get32(&bg_ref->fs->sb, inodes_per_group);
memset(block_bitmap.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(block_bitmap.data, i);
if (i < end_bit)
memset(block_bitmap.data + (i >> 3), 0xff, (end_bit - i) >> 3);
block_bitmap.dirty = true;
/* Save bitmap */
return ext4_block_set(bg_ref->fs->bdev, &block_bitmap);
}
/**@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;
uint32_t inode_size = ext4_get32(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;
uint32_t fblock;
if (inodes_in_group % inodes_per_block)
table_blocks++;
/* Compute initialization bounds */
uint32_t first_block = ext4_bg_get_inode_table_first_block(
bg_ref->block_group, sb);
uint32_t last_block = first_block + table_blocks - 1;
/* Initialization of all itable blocks */
for (fblock = first_block; fblock <= last_block; ++fblock) {
struct ext4_block block;
int rc = ext4_block_get(bg_ref->fs->bdev, &block, fblock);
if (rc != EOK)
return rc;
memset(block.data, 0, block_size);
block.dirty = true;
ext4_block_set(bg_ref->fs->bdev, &block);
if (rc != EOK)
return rc;
}
return EOK;
}
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 dsc_per_block = ext4_sb_get_block_size(&fs->sb) /
ext4_sb_get_desc_size(&fs->sb);
/* Block group descriptor table starts at the next block after superblock */
uint64_t block_id = ext4_get32(&fs->sb, first_data_block) + 1;
/* Find the block containing the descriptor we are looking for */
block_id += bgid / dsc_per_block;
uint32_t offset = (bgid % dsc_per_block) *
ext4_sb_get_desc_size(&fs->sb);
int rc = ext4_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;
if (ext4_bg_has_flag(ref->block_group,
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(ref->block_group,
EXT4_BLOCK_GROUP_BLOCK_UNINIT);
ref->dirty = true;
}
if (ext4_bg_has_flag(ref->block_group,
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(ref->block_group,
EXT4_BLOCK_GROUP_INODE_UNINIT);
if (!ext4_bg_has_flag(ref->block_group,
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(ref->block_group,
EXT4_BLOCK_GROUP_ITABLE_ZEROED);
}
ref->dirty = true;
}
return EOK;
}
/**@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;
/* Compute the checksum only if the filesystem supports it */
if (ext4_sb_check_read_only(sb,
EXT4_FEATURE_RO_COMPAT_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 le_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 *) &le_group, sizeof(le_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_check_feature_incompatible(sb,
EXT4_FEATURE_INCOMPAT_64BIT)) &&
(offset < ext4_sb_get_desc_size(sb)))
crc = ext4_bg_crc16(crc, ((uint8_t *) bg) + offset,
ext4_sb_get_desc_size(sb) - offset);
}
return crc;
}
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 checksum =
ext4_fs_bg_checksum(&ref->fs->sb, ref->index,
ref->block_group);
ref->block_group->checksum = to_le16(checksum);
/* Mark block dirty for writing changes to physical device */
ref->block.dirty = true;
}
/* Put back block, that contains block group descriptor */
return ext4_block_set(ref->fs->bdev, &ref->block);
}
int ext4_fs_get_inode_ref(struct ext4_fs *fs, uint32_t index,
struct ext4_inode_ref *ref)
{
/* 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 */
uint32_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 */
uint64_t block_id = inode_table_start +
(byte_offset_in_group / block_size);
rc = ext4_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;
return EOK;
}
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 */
ref->block.dirty = true;
}
/* Put back block, that contains i-node */
return ext4_block_set(ref->fs->bdev, &ref->block);
}
int ext4_fs_alloc_inode(struct ext4_fs *fs, struct ext4_inode_ref *inode_ref,
bool is_directory)
{
/* Check if newly allocated i-node will be a directory */
uint32_t i;
bool is_dir;
is_dir = is_directory;
/* 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);
if (rc != EOK) {
ext4_ialloc_free_inode(fs, index, is_dir);
return rc;
}
/* Initialize i-node */
struct ext4_inode *inode = inode_ref->inode;
uint16_t mode;
if (is_dir) {
/*
* Default directory permissions to be compatible with other systems
* 0777 (octal) == rwxrwxrwx
*/
mode = 0777;
mode |= EXT4_INODE_MODE_DIRECTORY;
ext4_inode_set_mode(&fs->sb, inode, mode);
ext4_inode_set_links_count(inode, 1); /* '.' entry */
} else {
/*
* Default file permissions to be compatible with other systems
* 0666 (octal) == rw-rw-rw-
*/
mode = 0666;
mode |= EXT4_INODE_MODE_FILE;
ext4_inode_set_mode(&fs->sb, inode, mode);
ext4_inode_set_links_count(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_modification_time(inode, 0);
ext4_inode_set_deletion_time(inode, 0);
ext4_inode_set_blocks_count(&fs->sb, inode, 0);
ext4_inode_set_flags(inode, 0);
ext4_inode_set_generation(inode, 0);
/* Reset blocks array */
for (i = 0; i < EXT4_INODE_BLOCKS; i++)
inode->blocks[i] = 0;
#if CONFIG_EXTENT_ENABLE
/* Initialize extents if needed */
if (ext4_sb_check_feature_incompatible(
&fs->sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
ext4_inode_set_flag(inode, EXT4_INODE_FLAG_EXTENTS);
/* Initialize extent root header */
struct ext4_extent_header *header = ext4_inode_get_extent_header(inode);
ext4_extent_header_set_depth(header, 0);
ext4_extent_header_set_entries_count(header, 0);
ext4_extent_header_set_generation(header, 0);
ext4_extent_header_set_magic(header, EXT4_EXTENT_MAGIC);
uint16_t max_entries = (EXT4_INODE_BLOCKS * sizeof(uint32_t) -
sizeof(struct ext4_extent_header)) / sizeof(struct ext4_extent);
ext4_extent_header_set_max_entries_count(header, max_entries);
}
#endif
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 suboffset;
#if CONFIG_EXTENT_ENABLE
/* For extents must be data block destroyed by other way */
if ((ext4_sb_check_feature_incompatible(&fs->sb,
EXT4_FEATURE_INCOMPAT_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 */
uint32_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_block_get(fs->bdev, &block, fblock);
if (rc != EOK)
return rc;
uint32_t ind_block;
for (offset = 0; offset < count; ++offset) {
ind_block = to_le32(((uint32_t *) block.data)[offset]);
if (ind_block != 0) {
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) {
int rc = ext4_block_get(fs->bdev, &block, fblock);
if (rc != EOK)
return rc;
uint32_t ind_block;
for ( offset = 0; offset < count; ++offset) {
ind_block = to_le32(((uint32_t *) block.data)[offset]);
if (ind_block != 0) {
rc = ext4_block_get(fs->bdev, &subblock, ind_block);
if (rc != EOK) {
ext4_block_set(fs->bdev, &block);
return rc;
}
uint32_t ind_subblock;
for (suboffset = 0; suboffset < count;
++suboffset) {
ind_subblock = to_le32(((uint32_t *)
subblock.data)[suboffset]);
if (ind_subblock != 0) {
rc = ext4_balloc_free_block(inode_ref, ind_subblock);
if (rc != EOK) {
ext4_block_set(fs->bdev, &subblock);
ext4_block_set(fs->bdev, &block);
return rc;
}
}
}
ext4_block_set(fs->bdev, &subblock);
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, 2, 0);
}
finish:
/* Mark inode dirty for writing to the physical device */
inode_ref->dirty = true;
/* Free block with extended attributes if present */
uint32_t xattr_block = ext4_inode_get_file_acl(
inode_ref->inode, &fs->sb);
if (xattr_block) {
int rc = ext4_balloc_free_block(inode_ref, xattr_block);
if (rc != EOK)
return rc;
ext4_inode_set_file_acl(inode_ref->inode, &fs->sb, 0);
}
/* Free inode by allocator */
int rc;
if (ext4_inode_is_type(&fs->sb, inode_ref->inode,
EXT4_INODE_MODE_DIRECTORY))
rc = ext4_ialloc_free_inode(fs, inode_ref->index, true);
else
rc = ext4_ialloc_free_inode(fs, inode_ref->index, false);
return rc;
}
int ext4_fs_truncate_inode(struct ext4_inode_ref *inode_ref,
uint64_t new_size)
{
struct ext4_sblock *sb = &inode_ref->fs->sb;
uint32_t i;
/* Check flags, if i-node can be truncated */
if (!ext4_inode_can_truncate(sb, inode_ref->inode))
return EINVAL;
/* If sizes are equal, nothing has to be done. */
uint64_t old_size = ext4_inode_get_size(sb, inode_ref->inode);
if (old_size == new_size)
return EOK;
/* It's not suppported to make the larger file by truncate operation */
if (old_size < new_size)
return EINVAL;
/* Compute how many blocks will be released */
uint64_t size_diff = old_size - new_size;
uint32_t block_size = ext4_sb_get_block_size(sb);
uint32_t diff_blocks_count = size_diff / block_size;
if (size_diff % block_size != 0)
diff_blocks_count++;
uint32_t old_blocks_count = old_size / block_size;
if (old_size % block_size != 0)
old_blocks_count++;
#if CONFIG_EXTENT_ENABLE
if ((ext4_sb_check_feature_incompatible(sb,
EXT4_FEATURE_INCOMPAT_EXTENTS)) &&
(ext4_inode_has_flag(inode_ref->inode, EXT4_INODE_FLAG_EXTENTS))) {
/* Extents require special operation */
int rc = ext4_extent_release_blocks_from(inode_ref,
old_blocks_count - diff_blocks_count);
if (rc != EOK)
return rc;
} else
#endif
{
/* Release data blocks from the end of file */
/* Starting from 1 because of logical blocks are numbered from 0 */
for (i = 1; i <= diff_blocks_count; ++i) {
int rc = ext4_fs_release_inode_block(inode_ref,
old_blocks_count - i);
if (rc != EOK)
return rc;
}
}
/* Update i-node */
ext4_inode_set_size(inode_ref->inode, new_size);
inode_ref->dirty = true;
return EOK;
}
int ext4_fs_get_inode_data_block_index(struct ext4_inode_ref *inode_ref,
uint64_t iblock, uint32_t *fblock)
{
struct ext4_fs *fs = inode_ref->fs;
/* For empty file is situation simple */
if (ext4_inode_get_size(&fs->sb, inode_ref->inode) == 0) {
*fblock = 0;
return EOK;
}
uint32_t current_block;
#if CONFIG_EXTENT_ENABLE
/* Handle i-node using extents */
if ((ext4_sb_check_feature_incompatible(&fs->sb,
EXT4_FEATURE_INCOMPAT_EXTENTS)) &&
(ext4_inode_has_flag(inode_ref->inode, EXT4_INODE_FLAG_EXTENTS))) {
int rc = ext4_extent_find_block(inode_ref, iblock, ¤t_block);
if (rc != EOK)
return rc;
*fblock = current_block;
return EOK;
}
#endif
struct ext4_inode *inode = inode_ref->inode;
/* Direct block are read directly from array in i-node structure */
if (iblock < EXT4_INODE_DIRECT_BLOCK_COUNT) {
current_block = ext4_inode_get_direct_block(inode, (uint32_t) iblock);
*fblock = current_block;
return EOK;
}
/* Determine indirection level of the target block */
unsigned int level = 0;
unsigned int i;
for (i = 1; i < 4; i++) {
if (iblock < fs->inode_block_limits[i]) {
level = i;
break;
}
}
if (level == 0)
return EIO;
/* Compute offsets for the topmost level */
uint64_t block_offset_in_level =
iblock - fs->inode_block_limits[level - 1];
current_block = ext4_inode_get_indirect_block(inode, level - 1);
uint32_t offset_in_block =
block_offset_in_level / fs->inode_blocks_per_level[level - 1];
/* Sparse file */
if (current_block == 0) {
*fblock = 0;
return EOK;
}
struct ext4_block block;
/*
* Navigate through other levels, until we find the block number
* or find null reference meaning we are dealing with sparse file
*/
while (level > 0) {
/* Load indirect block */
int rc = ext4_block_get(fs->bdev, &block, current_block);
if (rc != EOK)
return rc;
/* Read block address from indirect block */
current_block =
to_le32(((uint32_t *) block.data)[offset_in_block]);
/* Put back indirect block untouched */
rc = ext4_block_set(fs->bdev, &block);
if (rc != EOK)
return rc;
/* Check for sparse file */
if (current_block == 0) {
*fblock = 0;
return EOK;
}
/* Jump to the next level */
level--;
/* Termination condition - we have address of data block loaded */
if (level == 0)
break;
/* Visit the next level */
block_offset_in_level %= fs->inode_blocks_per_level[level];
offset_in_block =
block_offset_in_level / fs->inode_blocks_per_level[level - 1];
}
*fblock = current_block;
return EOK;
}
int ext4_fs_set_inode_data_block_index(struct ext4_inode_ref *inode_ref,
uint64_t iblock, uint32_t fblock)
{
struct ext4_fs *fs = inode_ref->fs;
#if CONFIG_EXTENT_ENABLE
/* Handle inode using extents */
if ((ext4_sb_check_feature_incompatible(&fs->sb,
EXT4_FEATURE_INCOMPAT_EXTENTS)) &&
(ext4_inode_has_flag(inode_ref->inode, EXT4_INODE_FLAG_EXTENTS))) {
/* Not reachable */
return ENOTSUP;
}
#endif
/* Handle simple case when we are dealing with direct reference */
if (iblock < EXT4_INODE_DIRECT_BLOCK_COUNT) {
ext4_inode_set_direct_block(inode_ref->inode, (uint32_t) iblock,
fblock);
inode_ref->dirty = true;
return EOK;
}
/* Determine the indirection level needed to get the desired block */
unsigned int level = 0;
unsigned int i;
for (i = 1; i < 4; i++) {
if (iblock < fs->inode_block_limits[i]) {
level = i;
break;
}
}
if (level == 0)
return EIO;
uint32_t block_size = ext4_sb_get_block_size(&fs->sb);
/* Compute offsets for the topmost level */
uint64_t block_offset_in_level =
iblock - fs->inode_block_limits[level - 1];
uint32_t current_block =
ext4_inode_get_indirect_block(inode_ref->inode, level - 1);
uint32_t offset_in_block =
block_offset_in_level / fs->inode_blocks_per_level[level - 1];
uint32_t new_block_addr;
struct ext4_block block;
struct ext4_block new_block;
/* Is needed to allocate indirect block on the i-node level */
if (current_block == 0) {
/* Allocate new indirect block */
int rc = ext4_balloc_alloc_block(inode_ref, &new_block_addr);
if (rc != EOK)
return rc;
/* Update i-node */
ext4_inode_set_indirect_block(inode_ref->inode, level - 1,
new_block_addr);
inode_ref->dirty = true;
/* Load newly allocated block */
rc = ext4_block_get(fs->bdev, &new_block, new_block_addr);
if (rc != EOK) {
ext4_balloc_free_block(inode_ref, new_block_addr);
return rc;
}
/* Initialize new block */
memset(new_block.data, 0, block_size);
new_block.dirty = true;
/* Put back the allocated block */
rc = ext4_block_set(fs->bdev, &new_block);
if (rc != EOK)
return rc;
current_block = new_block_addr;
}
/*
* Navigate through other levels, until we find the block number
* or find null reference meaning we are dealing with sparse file
*/
while (level > 0) {
int rc = ext4_block_get(fs->bdev, &block, current_block);
if (rc != EOK)
return rc;
current_block =
to_le32(((uint32_t *) block.data)[offset_in_block]);
if ((level > 1) && (current_block == 0)) {
/* Allocate new block */
rc = ext4_balloc_alloc_block(inode_ref, &new_block_addr);
if (rc != EOK) {
ext4_block_set(fs->bdev, &block);
return rc;
}
/* Load newly allocated block */
rc = ext4_block_get(fs->bdev, &new_block, new_block_addr);
if (rc != EOK) {
ext4_block_set(fs->bdev, &block);
return rc;
}
/* Initialize allocated block */
memset(new_block.data, 0, block_size);
new_block.dirty = true;
rc = ext4_block_set(fs->bdev, &new_block);
if (rc != EOK) {
ext4_block_set(fs->bdev, &block);
return rc;
}
/* Write block address to the parent */
((uint32_t *) block.data)[offset_in_block] =
to_le32(new_block_addr);
block.dirty = true;
current_block = new_block_addr;
}
/* Will be finished, write the fblock address */
if (level == 1) {
((uint32_t *) block.data)[offset_in_block] =
to_le32(fblock);
block.dirty = true;
}
rc = ext4_block_set(fs->bdev, &block);
if (rc != EOK)
return rc;
level--;
/*
* If we are on the last level, break here as
* there is no next level to visit
*/
if (level == 0)
break;
/* Visit the next level */
block_offset_in_level %= fs->inode_blocks_per_level[level];
offset_in_block =
block_offset_in_level / fs->inode_blocks_per_level[level - 1];
}
return EOK;
}
int ext4_fs_release_inode_block(struct ext4_inode_ref *inode_ref,
uint32_t iblock)
{
uint32_t fblock;
struct ext4_fs *fs = inode_ref->fs;
/* Extents are handled otherwise = there is not support in this function */
ext4_assert(!(ext4_sb_check_feature_incompatible(&fs->sb,
EXT4_FEATURE_INCOMPAT_EXTENTS) &&
(ext4_inode_has_flag(inode_ref->inode, EXT4_INODE_FLAG_EXTENTS))));
struct ext4_inode *inode = inode_ref->inode;
/* Handle simple case when we are dealing with direct reference */
if (iblock < EXT4_INODE_DIRECT_BLOCK_COUNT) {
fblock = ext4_inode_get_direct_block(inode, iblock);
/* Sparse file */
if (fblock == 0)
return EOK;
ext4_inode_set_direct_block(inode, iblock, 0);
return ext4_balloc_free_block(inode_ref, fblock);
}
/* Determine the indirection level needed to get the desired block */
unsigned int level = 0;
unsigned int i;
for (i = 1; i < 4; i++) {
if (iblock < fs->inode_block_limits[i]) {
level = i;
break;
}
}
if (level == 0)
return EIO;
/* Compute offsets for the topmost level */
uint64_t block_offset_in_level =
iblock - fs->inode_block_limits[level - 1];
uint32_t current_block =
ext4_inode_get_indirect_block(inode, level - 1);
uint32_t offset_in_block =
block_offset_in_level / fs->inode_blocks_per_level[level - 1];
/*
* Navigate through other levels, until we find the block number
* or find null reference meaning we are dealing with sparse file
*/
struct ext4_block block;
while (level > 0) {
/* Sparse check */
if (current_block == 0)
return EOK;
int rc = ext4_block_get(fs->bdev, &block, current_block);
if (rc != EOK)
return rc;
current_block =
to_le32(((uint32_t *) block.data)[offset_in_block]);
/* Set zero if physical data block address found */
if (level == 1) {
((uint32_t *) block.data)[offset_in_block] =
to_le32(0);
block.dirty = true;
}
rc = ext4_block_set(fs->bdev, &block);
if (rc != EOK)
return rc;
level--;
/*
* If we are on the last level, break here as
* there is no next level to visit
*/
if (level == 0)
break;
/* Visit the next level */
block_offset_in_level %= fs->inode_blocks_per_level[level];
offset_in_block =
block_offset_in_level / fs->inode_blocks_per_level[level - 1];
}
fblock = current_block;
if (fblock == 0)
return EOK;
/* Physical block is not referenced, it can be released */
return ext4_balloc_free_block(inode_ref, fblock);
}
int ext4_fs_append_inode_block(struct ext4_inode_ref *inode_ref,
uint32_t *fblock, uint32_t *iblock)
{
#if CONFIG_EXTENT_ENABLE
/* Handle extents separately */
if ((ext4_sb_check_feature_incompatible(&inode_ref->fs->sb,
EXT4_FEATURE_INCOMPAT_EXTENTS)) &&
(ext4_inode_has_flag(inode_ref->inode, EXT4_INODE_FLAG_EXTENTS))){
return ext4_extent_append_block(inode_ref, iblock, fblock, true);
}
#endif
struct ext4_sblock *sb = &inode_ref->fs->sb;
/* Compute next block index and allocate data block */
uint64_t inode_size = ext4_inode_get_size(sb, inode_ref->inode);
uint32_t block_size = ext4_sb_get_block_size(sb);
/* Align size i-node size */
if ((inode_size % block_size) != 0)
inode_size += block_size - (inode_size % block_size);
/* Logical blocks are numbered from 0 */
uint32_t new_block_idx = inode_size / block_size;
/* Allocate new physical block */
uint32_t phys_block;
int rc = ext4_balloc_alloc_block(inode_ref, &phys_block);
if (rc != EOK)
return rc;
/* Add physical block address to the i-node */
rc = ext4_fs_set_inode_data_block_index(inode_ref,
new_block_idx, phys_block);
if (rc != EOK) {
ext4_balloc_free_block(inode_ref, phys_block);
return rc;
}
/* Update i-node */
ext4_inode_set_size(inode_ref->inode, inode_size + block_size);
inode_ref->dirty = true;
*fblock = phys_block;
*iblock = new_block_idx;
return EOK;
}
/**
* @}
*/