u-boot/fs/ext4/ext4_write.c

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/*
* (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.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#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)(fs->bgd[i].block_id * fs->blksz),
fs->blk_bmaps[i], fs->blksz);
}
/* update inode table groups */
for (i = 0; i < fs->no_blkgrp; i++) {
put_ext4((uint64_t) (fs->bgd[i].inode_id * fs->blksz),
fs->inode_bmaps[i], fs->blksz);
}
/* update the block group descriptor table */
put_ext4((uint64_t)(fs->gdtable_blkno * 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(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(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(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(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(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(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((*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(
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(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(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(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(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(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(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(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(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(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) (blknr * 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)
(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) (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) (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(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(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;
}