u-boot/fs/ext4/ext4_write.c
Ma Haijun 0550870b1c fs/ext4: fix calling put_ext4 with truncated offset
Curently, we are using 32 bit multiplication to calculate the offset,
so the result will always be 32 bit.
This can silently cause file system corruption when performing a write
operation on partition larger than 4 GiB.

This patch address the issue by simply promoting the terms to 64 bit,
and let compilers decide how to do the multiplication efficiently.

Signed-off-by: Ma Haijun <mahaijuns@gmail.com>
2014-01-20 10:09:38 -05:00

994 lines
26 KiB
C

/*
* (C) Copyright 2011 - 2012 Samsung Electronics
* EXT4 filesystem implementation in Uboot by
* Uma Shankar <uma.shankar@samsung.com>
* Manjunatha C Achar <a.manjunatha@samsung.com>
*
* ext4ls and ext4load : Based on ext2 ls and load support in Uboot.
* Ext4 read optimization taken from Open-Moko
* Qi bootloader
*
* (C) Copyright 2004
* esd gmbh <www.esd-electronics.com>
* Reinhard Arlt <reinhard.arlt@esd-electronics.com>
*
* based on code from grub2 fs/ext2.c and fs/fshelp.c by
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2003, 2004 Free Software Foundation, Inc.
*
* ext4write : Based on generic ext4 protocol.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <linux/stat.h>
#include <div64.h>
#include "ext4_common.h"
static void ext4fs_update(void)
{
short i;
ext4fs_update_journal();
struct ext_filesystem *fs = get_fs();
/* update super block */
put_ext4((uint64_t)(SUPERBLOCK_SIZE),
(struct ext2_sblock *)fs->sb, (uint32_t)SUPERBLOCK_SIZE);
/* update block groups */
for (i = 0; i < fs->no_blkgrp; i++) {
fs->bgd[i].bg_checksum = ext4fs_checksum_update(i);
put_ext4((uint64_t)((uint64_t)fs->bgd[i].block_id * (uint64_t)fs->blksz),
fs->blk_bmaps[i], fs->blksz);
}
/* update inode table groups */
for (i = 0; i < fs->no_blkgrp; i++) {
put_ext4((uint64_t) ((uint64_t)fs->bgd[i].inode_id * (uint64_t)fs->blksz),
fs->inode_bmaps[i], fs->blksz);
}
/* update the block group descriptor table */
put_ext4((uint64_t)((uint64_t)fs->gdtable_blkno * (uint64_t)fs->blksz),
(struct ext2_block_group *)fs->gdtable,
(fs->blksz * fs->no_blk_pergdt));
ext4fs_dump_metadata();
gindex = 0;
gd_index = 0;
}
int ext4fs_get_bgdtable(void)
{
int status;
int grp_desc_size;
struct ext_filesystem *fs = get_fs();
grp_desc_size = sizeof(struct ext2_block_group);
fs->no_blk_pergdt = (fs->no_blkgrp * grp_desc_size) / fs->blksz;
if ((fs->no_blkgrp * grp_desc_size) % fs->blksz)
fs->no_blk_pergdt++;
/* allocate memory for gdtable */
fs->gdtable = zalloc(fs->blksz * fs->no_blk_pergdt);
if (!fs->gdtable)
return -ENOMEM;
/* read the group descriptor table */
status = ext4fs_devread((lbaint_t)fs->gdtable_blkno * fs->sect_perblk,
0, fs->blksz * fs->no_blk_pergdt, fs->gdtable);
if (status == 0)
goto fail;
if (ext4fs_log_gdt(fs->gdtable)) {
printf("Error in ext4fs_log_gdt\n");
return -1;
}
return 0;
fail:
free(fs->gdtable);
fs->gdtable = NULL;
return -1;
}
static void delete_single_indirect_block(struct ext2_inode *inode)
{
struct ext2_block_group *bgd = NULL;
static int prev_bg_bmap_idx = -1;
long int blknr;
int remainder;
int bg_idx;
int status;
unsigned int blk_per_grp = ext4fs_root->sblock.blocks_per_group;
struct ext_filesystem *fs = get_fs();
char *journal_buffer = zalloc(fs->blksz);
if (!journal_buffer) {
printf("No memory\n");
return;
}
/* get block group descriptor table */
bgd = (struct ext2_block_group *)fs->gdtable;
/* deleting the single indirect block associated with inode */
if (inode->b.blocks.indir_block != 0) {
debug("SIPB releasing %u\n", inode->b.blocks.indir_block);
blknr = inode->b.blocks.indir_block;
if (fs->blksz != 1024) {
bg_idx = blknr / blk_per_grp;
} else {
bg_idx = blknr / blk_per_grp;
remainder = blknr % blk_per_grp;
if (!remainder)
bg_idx--;
}
ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx], bg_idx);
bgd[bg_idx].free_blocks++;
fs->sb->free_blocks++;
/* journal backup */
if (prev_bg_bmap_idx != bg_idx) {
status =
ext4fs_devread((lbaint_t)bgd[bg_idx].block_id *
fs->sect_perblk, 0, fs->blksz,
journal_buffer);
if (status == 0)
goto fail;
if (ext4fs_log_journal
(journal_buffer, bgd[bg_idx].block_id))
goto fail;
prev_bg_bmap_idx = bg_idx;
}
}
fail:
free(journal_buffer);
}
static void delete_double_indirect_block(struct ext2_inode *inode)
{
int i;
short status;
static int prev_bg_bmap_idx = -1;
long int blknr;
int remainder;
int bg_idx;
unsigned int blk_per_grp = ext4fs_root->sblock.blocks_per_group;
unsigned int *di_buffer = NULL;
unsigned int *DIB_start_addr = NULL;
struct ext2_block_group *bgd = NULL;
struct ext_filesystem *fs = get_fs();
char *journal_buffer = zalloc(fs->blksz);
if (!journal_buffer) {
printf("No memory\n");
return;
}
/* get the block group descriptor table */
bgd = (struct ext2_block_group *)fs->gdtable;
if (inode->b.blocks.double_indir_block != 0) {
di_buffer = zalloc(fs->blksz);
if (!di_buffer) {
printf("No memory\n");
return;
}
DIB_start_addr = (unsigned int *)di_buffer;
blknr = inode->b.blocks.double_indir_block;
status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0,
fs->blksz, (char *)di_buffer);
for (i = 0; i < fs->blksz / sizeof(int); i++) {
if (*di_buffer == 0)
break;
debug("DICB releasing %u\n", *di_buffer);
if (fs->blksz != 1024) {
bg_idx = (*di_buffer) / blk_per_grp;
} else {
bg_idx = (*di_buffer) / blk_per_grp;
remainder = (*di_buffer) % blk_per_grp;
if (!remainder)
bg_idx--;
}
ext4fs_reset_block_bmap(*di_buffer,
fs->blk_bmaps[bg_idx], bg_idx);
di_buffer++;
bgd[bg_idx].free_blocks++;
fs->sb->free_blocks++;
/* journal backup */
if (prev_bg_bmap_idx != bg_idx) {
status = ext4fs_devread((lbaint_t)
bgd[bg_idx].block_id
* fs->sect_perblk, 0,
fs->blksz,
journal_buffer);
if (status == 0)
goto fail;
if (ext4fs_log_journal(journal_buffer,
bgd[bg_idx].block_id))
goto fail;
prev_bg_bmap_idx = bg_idx;
}
}
/* removing the parent double indirect block */
blknr = inode->b.blocks.double_indir_block;
if (fs->blksz != 1024) {
bg_idx = blknr / blk_per_grp;
} else {
bg_idx = blknr / blk_per_grp;
remainder = blknr % blk_per_grp;
if (!remainder)
bg_idx--;
}
ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx], bg_idx);
bgd[bg_idx].free_blocks++;
fs->sb->free_blocks++;
/* journal backup */
if (prev_bg_bmap_idx != bg_idx) {
memset(journal_buffer, '\0', fs->blksz);
status = ext4fs_devread((lbaint_t)bgd[bg_idx].block_id *
fs->sect_perblk, 0, fs->blksz,
journal_buffer);
if (status == 0)
goto fail;
if (ext4fs_log_journal(journal_buffer,
bgd[bg_idx].block_id))
goto fail;
prev_bg_bmap_idx = bg_idx;
}
debug("DIPB releasing %ld\n", blknr);
}
fail:
free(DIB_start_addr);
free(journal_buffer);
}
static void delete_triple_indirect_block(struct ext2_inode *inode)
{
int i, j;
short status;
static int prev_bg_bmap_idx = -1;
long int blknr;
int remainder;
int bg_idx;
unsigned int blk_per_grp = ext4fs_root->sblock.blocks_per_group;
unsigned int *tigp_buffer = NULL;
unsigned int *tib_start_addr = NULL;
unsigned int *tip_buffer = NULL;
unsigned int *tipb_start_addr = NULL;
struct ext2_block_group *bgd = NULL;
struct ext_filesystem *fs = get_fs();
char *journal_buffer = zalloc(fs->blksz);
if (!journal_buffer) {
printf("No memory\n");
return;
}
/* get block group descriptor table */
bgd = (struct ext2_block_group *)fs->gdtable;
if (inode->b.blocks.triple_indir_block != 0) {
tigp_buffer = zalloc(fs->blksz);
if (!tigp_buffer) {
printf("No memory\n");
return;
}
tib_start_addr = (unsigned int *)tigp_buffer;
blknr = inode->b.blocks.triple_indir_block;
status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0,
fs->blksz, (char *)tigp_buffer);
for (i = 0; i < fs->blksz / sizeof(int); i++) {
if (*tigp_buffer == 0)
break;
debug("tigp buffer releasing %u\n", *tigp_buffer);
tip_buffer = zalloc(fs->blksz);
if (!tip_buffer)
goto fail;
tipb_start_addr = (unsigned int *)tip_buffer;
status = ext4fs_devread((lbaint_t)(*tigp_buffer) *
fs->sect_perblk, 0, fs->blksz,
(char *)tip_buffer);
for (j = 0; j < fs->blksz / sizeof(int); j++) {
if (*tip_buffer == 0)
break;
if (fs->blksz != 1024) {
bg_idx = (*tip_buffer) / blk_per_grp;
} else {
bg_idx = (*tip_buffer) / blk_per_grp;
remainder = (*tip_buffer) % blk_per_grp;
if (!remainder)
bg_idx--;
}
ext4fs_reset_block_bmap(*tip_buffer,
fs->blk_bmaps[bg_idx],
bg_idx);
tip_buffer++;
bgd[bg_idx].free_blocks++;
fs->sb->free_blocks++;
/* journal backup */
if (prev_bg_bmap_idx != bg_idx) {
status =
ext4fs_devread(
(lbaint_t)
bgd[bg_idx].block_id *
fs->sect_perblk, 0,
fs->blksz,
journal_buffer);
if (status == 0)
goto fail;
if (ext4fs_log_journal(journal_buffer,
bgd[bg_idx].
block_id))
goto fail;
prev_bg_bmap_idx = bg_idx;
}
}
free(tipb_start_addr);
tipb_start_addr = NULL;
/*
* removing the grand parent blocks
* which is connected to inode
*/
if (fs->blksz != 1024) {
bg_idx = (*tigp_buffer) / blk_per_grp;
} else {
bg_idx = (*tigp_buffer) / blk_per_grp;
remainder = (*tigp_buffer) % blk_per_grp;
if (!remainder)
bg_idx--;
}
ext4fs_reset_block_bmap(*tigp_buffer,
fs->blk_bmaps[bg_idx], bg_idx);
tigp_buffer++;
bgd[bg_idx].free_blocks++;
fs->sb->free_blocks++;
/* journal backup */
if (prev_bg_bmap_idx != bg_idx) {
memset(journal_buffer, '\0', fs->blksz);
status =
ext4fs_devread((lbaint_t)
bgd[bg_idx].block_id *
fs->sect_perblk, 0,
fs->blksz, journal_buffer);
if (status == 0)
goto fail;
if (ext4fs_log_journal(journal_buffer,
bgd[bg_idx].block_id))
goto fail;
prev_bg_bmap_idx = bg_idx;
}
}
/* removing the grand parent triple indirect block */
blknr = inode->b.blocks.triple_indir_block;
if (fs->blksz != 1024) {
bg_idx = blknr / blk_per_grp;
} else {
bg_idx = blknr / blk_per_grp;
remainder = blknr % blk_per_grp;
if (!remainder)
bg_idx--;
}
ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx], bg_idx);
bgd[bg_idx].free_blocks++;
fs->sb->free_blocks++;
/* journal backup */
if (prev_bg_bmap_idx != bg_idx) {
memset(journal_buffer, '\0', fs->blksz);
status = ext4fs_devread((lbaint_t)bgd[bg_idx].block_id *
fs->sect_perblk, 0, fs->blksz,
journal_buffer);
if (status == 0)
goto fail;
if (ext4fs_log_journal(journal_buffer,
bgd[bg_idx].block_id))
goto fail;
prev_bg_bmap_idx = bg_idx;
}
debug("tigp buffer itself releasing %ld\n", blknr);
}
fail:
free(tib_start_addr);
free(tipb_start_addr);
free(journal_buffer);
}
static int ext4fs_delete_file(int inodeno)
{
struct ext2_inode inode;
short status;
int i;
int remainder;
long int blknr;
int bg_idx;
int ibmap_idx;
char *read_buffer = NULL;
char *start_block_address = NULL;
unsigned int no_blocks;
static int prev_bg_bmap_idx = -1;
unsigned int inodes_per_block;
long int blkno;
unsigned int blkoff;
unsigned int blk_per_grp = ext4fs_root->sblock.blocks_per_group;
unsigned int inode_per_grp = ext4fs_root->sblock.inodes_per_group;
struct ext2_inode *inode_buffer = NULL;
struct ext2_block_group *bgd = NULL;
struct ext_filesystem *fs = get_fs();
char *journal_buffer = zalloc(fs->blksz);
if (!journal_buffer)
return -ENOMEM;
/* get the block group descriptor table */
bgd = (struct ext2_block_group *)fs->gdtable;
status = ext4fs_read_inode(ext4fs_root, inodeno, &inode);
if (status == 0)
goto fail;
/* read the block no allocated to a file */
no_blocks = inode.size / fs->blksz;
if (inode.size % fs->blksz)
no_blocks++;
if (le32_to_cpu(inode.flags) & EXT4_EXTENTS_FL) {
struct ext2fs_node *node_inode =
zalloc(sizeof(struct ext2fs_node));
if (!node_inode)
goto fail;
node_inode->data = ext4fs_root;
node_inode->ino = inodeno;
node_inode->inode_read = 0;
memcpy(&(node_inode->inode), &inode, sizeof(struct ext2_inode));
for (i = 0; i < no_blocks; i++) {
blknr = read_allocated_block(&(node_inode->inode), i);
if (fs->blksz != 1024) {
bg_idx = blknr / blk_per_grp;
} else {
bg_idx = blknr / blk_per_grp;
remainder = blknr % blk_per_grp;
if (!remainder)
bg_idx--;
}
ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx],
bg_idx);
debug("EXT4_EXTENTS Block releasing %ld: %d\n",
blknr, bg_idx);
bgd[bg_idx].free_blocks++;
fs->sb->free_blocks++;
/* journal backup */
if (prev_bg_bmap_idx != bg_idx) {
status =
ext4fs_devread((lbaint_t)
bgd[bg_idx].block_id *
fs->sect_perblk, 0,
fs->blksz, journal_buffer);
if (status == 0)
goto fail;
if (ext4fs_log_journal(journal_buffer,
bgd[bg_idx].block_id))
goto fail;
prev_bg_bmap_idx = bg_idx;
}
}
if (node_inode) {
free(node_inode);
node_inode = NULL;
}
} else {
delete_single_indirect_block(&inode);
delete_double_indirect_block(&inode);
delete_triple_indirect_block(&inode);
/* read the block no allocated to a file */
no_blocks = inode.size / fs->blksz;
if (inode.size % fs->blksz)
no_blocks++;
for (i = 0; i < no_blocks; i++) {
blknr = read_allocated_block(&inode, i);
if (fs->blksz != 1024) {
bg_idx = blknr / blk_per_grp;
} else {
bg_idx = blknr / blk_per_grp;
remainder = blknr % blk_per_grp;
if (!remainder)
bg_idx--;
}
ext4fs_reset_block_bmap(blknr, fs->blk_bmaps[bg_idx],
bg_idx);
debug("ActualB releasing %ld: %d\n", blknr, bg_idx);
bgd[bg_idx].free_blocks++;
fs->sb->free_blocks++;
/* journal backup */
if (prev_bg_bmap_idx != bg_idx) {
memset(journal_buffer, '\0', fs->blksz);
status = ext4fs_devread((lbaint_t)
bgd[bg_idx].block_id
* fs->sect_perblk,
0, fs->blksz,
journal_buffer);
if (status == 0)
goto fail;
if (ext4fs_log_journal(journal_buffer,
bgd[bg_idx].block_id))
goto fail;
prev_bg_bmap_idx = bg_idx;
}
}
}
/* from the inode no to blockno */
inodes_per_block = fs->blksz / fs->inodesz;
ibmap_idx = inodeno / inode_per_grp;
/* get the block no */
inodeno--;
blkno = __le32_to_cpu(bgd[ibmap_idx].inode_table_id) +
(inodeno % __le32_to_cpu(inode_per_grp)) / inodes_per_block;
/* get the offset of the inode */
blkoff = ((inodeno) % inodes_per_block) * fs->inodesz;
/* read the block no containing the inode */
read_buffer = zalloc(fs->blksz);
if (!read_buffer)
goto fail;
start_block_address = read_buffer;
status = ext4fs_devread((lbaint_t)blkno * fs->sect_perblk,
0, fs->blksz, read_buffer);
if (status == 0)
goto fail;
if (ext4fs_log_journal(read_buffer, blkno))
goto fail;
read_buffer = read_buffer + blkoff;
inode_buffer = (struct ext2_inode *)read_buffer;
memset(inode_buffer, '\0', sizeof(struct ext2_inode));
/* write the inode to original position in inode table */
if (ext4fs_put_metadata(start_block_address, blkno))
goto fail;
/* update the respective inode bitmaps */
inodeno++;
ext4fs_reset_inode_bmap(inodeno, fs->inode_bmaps[ibmap_idx], ibmap_idx);
bgd[ibmap_idx].free_inodes++;
fs->sb->free_inodes++;
/* journal backup */
memset(journal_buffer, '\0', fs->blksz);
status = ext4fs_devread((lbaint_t)bgd[ibmap_idx].inode_id *
fs->sect_perblk, 0, fs->blksz, journal_buffer);
if (status == 0)
goto fail;
if (ext4fs_log_journal(journal_buffer, bgd[ibmap_idx].inode_id))
goto fail;
ext4fs_update();
ext4fs_deinit();
if (ext4fs_init() != 0) {
printf("error in File System init\n");
goto fail;
}
free(start_block_address);
free(journal_buffer);
return 0;
fail:
free(start_block_address);
free(journal_buffer);
return -1;
}
int ext4fs_init(void)
{
short status;
int i;
unsigned int real_free_blocks = 0;
struct ext_filesystem *fs = get_fs();
/* populate fs */
fs->blksz = EXT2_BLOCK_SIZE(ext4fs_root);
fs->inodesz = INODE_SIZE_FILESYSTEM(ext4fs_root);
fs->sect_perblk = fs->blksz >> fs->dev_desc->log2blksz;
/* get the superblock */
fs->sb = zalloc(SUPERBLOCK_SIZE);
if (!fs->sb)
return -ENOMEM;
if (!ext4_read_superblock((char *)fs->sb))
goto fail;
/* init journal */
if (ext4fs_init_journal())
goto fail;
/* get total no of blockgroups */
fs->no_blkgrp = (uint32_t)ext4fs_div_roundup(
(ext4fs_root->sblock.total_blocks -
ext4fs_root->sblock.first_data_block),
ext4fs_root->sblock.blocks_per_group);
/* get the block group descriptor table */
fs->gdtable_blkno = ((EXT2_MIN_BLOCK_SIZE == fs->blksz) + 1);
if (ext4fs_get_bgdtable() == -1) {
printf("Error in getting the block group descriptor table\n");
goto fail;
}
fs->bgd = (struct ext2_block_group *)fs->gdtable;
/* load all the available bitmap block of the partition */
fs->blk_bmaps = zalloc(fs->no_blkgrp * sizeof(char *));
if (!fs->blk_bmaps)
goto fail;
for (i = 0; i < fs->no_blkgrp; i++) {
fs->blk_bmaps[i] = zalloc(fs->blksz);
if (!fs->blk_bmaps[i])
goto fail;
}
for (i = 0; i < fs->no_blkgrp; i++) {
status =
ext4fs_devread((lbaint_t)fs->bgd[i].block_id *
fs->sect_perblk, 0,
fs->blksz, (char *)fs->blk_bmaps[i]);
if (status == 0)
goto fail;
}
/* load all the available inode bitmap of the partition */
fs->inode_bmaps = zalloc(fs->no_blkgrp * sizeof(unsigned char *));
if (!fs->inode_bmaps)
goto fail;
for (i = 0; i < fs->no_blkgrp; i++) {
fs->inode_bmaps[i] = zalloc(fs->blksz);
if (!fs->inode_bmaps[i])
goto fail;
}
for (i = 0; i < fs->no_blkgrp; i++) {
status = ext4fs_devread((lbaint_t)fs->bgd[i].inode_id *
fs->sect_perblk,
0, fs->blksz,
(char *)fs->inode_bmaps[i]);
if (status == 0)
goto fail;
}
/*
* check filesystem consistency with free blocks of file system
* some time we observed that superblock freeblocks does not match
* with the blockgroups freeblocks when improper
* reboot of a linux kernel
*/
for (i = 0; i < fs->no_blkgrp; i++)
real_free_blocks = real_free_blocks + fs->bgd[i].free_blocks;
if (real_free_blocks != fs->sb->free_blocks)
fs->sb->free_blocks = real_free_blocks;
return 0;
fail:
ext4fs_deinit();
return -1;
}
void ext4fs_deinit(void)
{
int i;
struct ext2_inode inode_journal;
struct journal_superblock_t *jsb;
long int blknr;
struct ext_filesystem *fs = get_fs();
/* free journal */
char *temp_buff = zalloc(fs->blksz);
if (temp_buff) {
ext4fs_read_inode(ext4fs_root, EXT2_JOURNAL_INO,
&inode_journal);
blknr = read_allocated_block(&inode_journal,
EXT2_JOURNAL_SUPERBLOCK);
ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0, fs->blksz,
temp_buff);
jsb = (struct journal_superblock_t *)temp_buff;
jsb->s_start = cpu_to_be32(0);
put_ext4((uint64_t) ((uint64_t)blknr * (uint64_t)fs->blksz),
(struct journal_superblock_t *)temp_buff, fs->blksz);
free(temp_buff);
}
ext4fs_free_journal();
/* get the superblock */
ext4_read_superblock((char *)fs->sb);
fs->sb->feature_incompat &= ~EXT3_FEATURE_INCOMPAT_RECOVER;
put_ext4((uint64_t)(SUPERBLOCK_SIZE),
(struct ext2_sblock *)fs->sb, (uint32_t)SUPERBLOCK_SIZE);
free(fs->sb);
fs->sb = NULL;
if (fs->blk_bmaps) {
for (i = 0; i < fs->no_blkgrp; i++) {
free(fs->blk_bmaps[i]);
fs->blk_bmaps[i] = NULL;
}
free(fs->blk_bmaps);
fs->blk_bmaps = NULL;
}
if (fs->inode_bmaps) {
for (i = 0; i < fs->no_blkgrp; i++) {
free(fs->inode_bmaps[i]);
fs->inode_bmaps[i] = NULL;
}
free(fs->inode_bmaps);
fs->inode_bmaps = NULL;
}
free(fs->gdtable);
fs->gdtable = NULL;
fs->bgd = NULL;
/*
* reinitiliazed the global inode and
* block bitmap first execution check variables
*/
fs->first_pass_ibmap = 0;
fs->first_pass_bbmap = 0;
fs->curr_inode_no = 0;
fs->curr_blkno = 0;
}
static int ext4fs_write_file(struct ext2_inode *file_inode,
int pos, unsigned int len, char *buf)
{
int i;
int blockcnt;
unsigned int filesize = __le32_to_cpu(file_inode->size);
struct ext_filesystem *fs = get_fs();
int log2blksz = fs->dev_desc->log2blksz;
int log2_fs_blocksize = LOG2_BLOCK_SIZE(ext4fs_root) - log2blksz;
int previous_block_number = -1;
int delayed_start = 0;
int delayed_extent = 0;
int delayed_next = 0;
char *delayed_buf = NULL;
/* Adjust len so it we can't read past the end of the file. */
if (len > filesize)
len = filesize;
blockcnt = ((len + pos) + fs->blksz - 1) / fs->blksz;
for (i = pos / fs->blksz; i < blockcnt; i++) {
long int blknr;
int blockend = fs->blksz;
int skipfirst = 0;
blknr = read_allocated_block(file_inode, i);
if (blknr < 0)
return -1;
blknr = blknr << log2_fs_blocksize;
if (blknr) {
if (previous_block_number != -1) {
if (delayed_next == blknr) {
delayed_extent += blockend;
delayed_next += blockend >> log2blksz;
} else { /* spill */
put_ext4((uint64_t)
((uint64_t)delayed_start << log2blksz),
delayed_buf,
(uint32_t) delayed_extent);
previous_block_number = blknr;
delayed_start = blknr;
delayed_extent = blockend;
delayed_buf = buf;
delayed_next = blknr +
(blockend >> log2blksz);
}
} else {
previous_block_number = blknr;
delayed_start = blknr;
delayed_extent = blockend;
delayed_buf = buf;
delayed_next = blknr +
(blockend >> log2blksz);
}
} else {
if (previous_block_number != -1) {
/* spill */
put_ext4((uint64_t) ((uint64_t)delayed_start <<
log2blksz),
delayed_buf,
(uint32_t) delayed_extent);
previous_block_number = -1;
}
memset(buf, 0, fs->blksz - skipfirst);
}
buf += fs->blksz - skipfirst;
}
if (previous_block_number != -1) {
/* spill */
put_ext4((uint64_t) ((uint64_t)delayed_start << log2blksz),
delayed_buf, (uint32_t) delayed_extent);
previous_block_number = -1;
}
return len;
}
int ext4fs_write(const char *fname, unsigned char *buffer,
unsigned long sizebytes)
{
int ret = 0;
struct ext2_inode *file_inode = NULL;
unsigned char *inode_buffer = NULL;
int parent_inodeno;
int inodeno;
time_t timestamp = 0;
uint64_t bytes_reqd_for_file;
unsigned int blks_reqd_for_file;
unsigned int blocks_remaining;
int existing_file_inodeno;
char *temp_ptr = NULL;
long int itable_blkno;
long int parent_itable_blkno;
long int blkoff;
struct ext2_sblock *sblock = &(ext4fs_root->sblock);
unsigned int inodes_per_block;
unsigned int ibmap_idx;
struct ext_filesystem *fs = get_fs();
ALLOC_CACHE_ALIGN_BUFFER(char, filename, 256);
memset(filename, 0x00, sizeof(filename));
g_parent_inode = zalloc(sizeof(struct ext2_inode));
if (!g_parent_inode)
goto fail;
if (ext4fs_init() != 0) {
printf("error in File System init\n");
return -1;
}
inodes_per_block = fs->blksz / fs->inodesz;
parent_inodeno = ext4fs_get_parent_inode_num(fname, filename, F_FILE);
if (parent_inodeno == -1)
goto fail;
if (ext4fs_iget(parent_inodeno, g_parent_inode))
goto fail;
/* check if the filename is already present in root */
existing_file_inodeno = ext4fs_filename_check(filename);
if (existing_file_inodeno != -1) {
ret = ext4fs_delete_file(existing_file_inodeno);
fs->first_pass_bbmap = 0;
fs->curr_blkno = 0;
fs->first_pass_ibmap = 0;
fs->curr_inode_no = 0;
if (ret)
goto fail;
}
/* calucalate how many blocks required */
bytes_reqd_for_file = sizebytes;
blks_reqd_for_file = lldiv(bytes_reqd_for_file, fs->blksz);
if (do_div(bytes_reqd_for_file, fs->blksz) != 0) {
blks_reqd_for_file++;
debug("total bytes for a file %u\n", blks_reqd_for_file);
}
blocks_remaining = blks_reqd_for_file;
/* test for available space in partition */
if (fs->sb->free_blocks < blks_reqd_for_file) {
printf("Not enough space on partition !!!\n");
goto fail;
}
ext4fs_update_parent_dentry(filename, &inodeno, FILETYPE_REG);
/* prepare file inode */
inode_buffer = zalloc(fs->inodesz);
if (!inode_buffer)
goto fail;
file_inode = (struct ext2_inode *)inode_buffer;
file_inode->mode = S_IFREG | S_IRWXU |
S_IRGRP | S_IROTH | S_IXGRP | S_IXOTH;
/* ToDo: Update correct time */
file_inode->mtime = timestamp;
file_inode->atime = timestamp;
file_inode->ctime = timestamp;
file_inode->nlinks = 1;
file_inode->size = sizebytes;
/* Allocate data blocks */
ext4fs_allocate_blocks(file_inode, blocks_remaining,
&blks_reqd_for_file);
file_inode->blockcnt = (blks_reqd_for_file * fs->blksz) >>
fs->dev_desc->log2blksz;
temp_ptr = zalloc(fs->blksz);
if (!temp_ptr)
goto fail;
ibmap_idx = inodeno / ext4fs_root->sblock.inodes_per_group;
inodeno--;
itable_blkno = __le32_to_cpu(fs->bgd[ibmap_idx].inode_table_id) +
(inodeno % __le32_to_cpu(sblock->inodes_per_group)) /
inodes_per_block;
blkoff = (inodeno % inodes_per_block) * fs->inodesz;
ext4fs_devread((lbaint_t)itable_blkno * fs->sect_perblk, 0, fs->blksz,
temp_ptr);
if (ext4fs_log_journal(temp_ptr, itable_blkno))
goto fail;
memcpy(temp_ptr + blkoff, inode_buffer, fs->inodesz);
if (ext4fs_put_metadata(temp_ptr, itable_blkno))
goto fail;
/* copy the file content into data blocks */
if (ext4fs_write_file(file_inode, 0, sizebytes, (char *)buffer) == -1) {
printf("Error in copying content\n");
goto fail;
}
ibmap_idx = parent_inodeno / ext4fs_root->sblock.inodes_per_group;
parent_inodeno--;
parent_itable_blkno = __le32_to_cpu(fs->bgd[ibmap_idx].inode_table_id) +
(parent_inodeno %
__le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
blkoff = (parent_inodeno % inodes_per_block) * fs->inodesz;
if (parent_itable_blkno != itable_blkno) {
memset(temp_ptr, '\0', fs->blksz);
ext4fs_devread((lbaint_t)parent_itable_blkno * fs->sect_perblk,
0, fs->blksz, temp_ptr);
if (ext4fs_log_journal(temp_ptr, parent_itable_blkno))
goto fail;
memcpy(temp_ptr + blkoff, g_parent_inode,
sizeof(struct ext2_inode));
if (ext4fs_put_metadata(temp_ptr, parent_itable_blkno))
goto fail;
free(temp_ptr);
} else {
/*
* If parent and child fall in same inode table block
* both should be kept in 1 buffer
*/
memcpy(temp_ptr + blkoff, g_parent_inode,
sizeof(struct ext2_inode));
gd_index--;
if (ext4fs_put_metadata(temp_ptr, itable_blkno))
goto fail;
free(temp_ptr);
}
ext4fs_update();
ext4fs_deinit();
fs->first_pass_bbmap = 0;
fs->curr_blkno = 0;
fs->first_pass_ibmap = 0;
fs->curr_inode_no = 0;
free(inode_buffer);
free(g_parent_inode);
g_parent_inode = NULL;
return 0;
fail:
ext4fs_deinit();
free(inode_buffer);
free(g_parent_inode);
g_parent_inode = NULL;
return -1;
}