ext4fs write support
Signed-off-by: Uma Shankar <uma.shankar@samsung.com>
Signed-off-by: Manjunatha C Achar <a.manjunatha@samsung.com>
Signed-off-by: Iqbal Shareef <iqbal.ams@samsung.com>
Signed-off-by: Hakgoo Lee <goodguy.lee@samsung.com>
diff --git a/fs/ext4/ext4_common.c b/fs/ext4/ext4_common.c
index 2ddbb50..083e45e 100644
--- a/fs/ext4/ext4_common.c
+++ b/fs/ext4/ext4_common.c
@@ -14,6 +14,8 @@
* 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
@@ -54,6 +56,1357 @@
struct ext2_inode *g_parent_inode;
static int symlinknest;
+#if defined(CONFIG_CMD_EXT4_WRITE)
+uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n)
+{
+ uint32_t res = size / n;
+ if (res * n != size)
+ res++;
+
+ return res;
+}
+
+void put_ext4(uint64_t off, void *buf, uint32_t size)
+{
+ uint64_t startblock;
+ uint64_t remainder;
+ unsigned char *temp_ptr = NULL;
+ unsigned char sec_buf[SECTOR_SIZE];
+ struct ext_filesystem *fs = get_fs();
+
+ startblock = off / (uint64_t)SECTOR_SIZE;
+ startblock += part_offset;
+ remainder = off % (uint64_t)SECTOR_SIZE;
+ remainder &= SECTOR_SIZE - 1;
+
+ if (fs->dev_desc == NULL)
+ return;
+
+ if ((startblock + (size / SECTOR_SIZE)) >
+ (part_offset + fs->total_sect)) {
+ printf("part_offset is %lu\n", part_offset);
+ printf("total_sector is %llu\n", fs->total_sect);
+ printf("error: overflow occurs\n");
+ return;
+ }
+
+ if (remainder) {
+ if (fs->dev_desc->block_read) {
+ fs->dev_desc->block_read(fs->dev_desc->dev,
+ startblock, 1, sec_buf);
+ temp_ptr = sec_buf;
+ memcpy((temp_ptr + remainder),
+ (unsigned char *)buf, size);
+ fs->dev_desc->block_write(fs->dev_desc->dev,
+ startblock, 1, sec_buf);
+ }
+ } else {
+ if (size / SECTOR_SIZE != 0) {
+ fs->dev_desc->block_write(fs->dev_desc->dev,
+ startblock,
+ size / SECTOR_SIZE,
+ (unsigned long *)buf);
+ } else {
+ fs->dev_desc->block_read(fs->dev_desc->dev,
+ startblock, 1, sec_buf);
+ temp_ptr = sec_buf;
+ memcpy(temp_ptr, buf, size);
+ fs->dev_desc->block_write(fs->dev_desc->dev,
+ startblock, 1,
+ (unsigned long *)sec_buf);
+ }
+ }
+}
+
+static int _get_new_inode_no(unsigned char *buffer)
+{
+ struct ext_filesystem *fs = get_fs();
+ unsigned char input;
+ int operand, status;
+ int count = 1;
+ int j = 0;
+
+ /* get the blocksize of the filesystem */
+ unsigned char *ptr = buffer;
+ while (*ptr == 255) {
+ ptr++;
+ count += 8;
+ if (count > ext4fs_root->sblock.inodes_per_group)
+ return -1;
+ }
+
+ for (j = 0; j < fs->blksz; j++) {
+ input = *ptr;
+ int i = 0;
+ while (i <= 7) {
+ operand = 1 << i;
+ status = input & operand;
+ if (status) {
+ i++;
+ count++;
+ } else {
+ *ptr |= operand;
+ return count;
+ }
+ }
+ ptr = ptr + 1;
+ }
+
+ return -1;
+}
+
+static int _get_new_blk_no(unsigned char *buffer)
+{
+ unsigned char input;
+ int operand, status;
+ int count = 0;
+ int j = 0;
+ unsigned char *ptr = buffer;
+ struct ext_filesystem *fs = get_fs();
+
+ if (fs->blksz != 1024)
+ count = 0;
+ else
+ count = 1;
+
+ while (*ptr == 255) {
+ ptr++;
+ count += 8;
+ if (count == (fs->blksz * 8))
+ return -1;
+ }
+
+ for (j = 0; j < fs->blksz; j++) {
+ input = *ptr;
+ int i = 0;
+ while (i <= 7) {
+ operand = 1 << i;
+ status = input & operand;
+ if (status) {
+ i++;
+ count++;
+ } else {
+ *ptr |= operand;
+ return count;
+ }
+ }
+ ptr = ptr + 1;
+ }
+
+ return -1;
+}
+
+int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index)
+{
+ int i, remainder, status;
+ unsigned char *ptr = buffer;
+ unsigned char operand;
+ i = blockno / 8;
+ remainder = blockno % 8;
+ int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
+
+ i = i - (index * blocksize);
+ if (blocksize != 1024) {
+ ptr = ptr + i;
+ operand = 1 << remainder;
+ status = *ptr & operand;
+ if (status)
+ return -1;
+
+ *ptr = *ptr | operand;
+ return 0;
+ } else {
+ if (remainder == 0) {
+ ptr = ptr + i - 1;
+ operand = (1 << 7);
+ } else {
+ ptr = ptr + i;
+ operand = (1 << (remainder - 1));
+ }
+ status = *ptr & operand;
+ if (status)
+ return -1;
+
+ *ptr = *ptr | operand;
+ return 0;
+ }
+}
+
+void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index)
+{
+ int i, remainder, status;
+ unsigned char *ptr = buffer;
+ unsigned char operand;
+ i = blockno / 8;
+ remainder = blockno % 8;
+ int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
+
+ i = i - (index * blocksize);
+ if (blocksize != 1024) {
+ ptr = ptr + i;
+ operand = (1 << remainder);
+ status = *ptr & operand;
+ if (status)
+ *ptr = *ptr & ~(operand);
+ } else {
+ if (remainder == 0) {
+ ptr = ptr + i - 1;
+ operand = (1 << 7);
+ } else {
+ ptr = ptr + i;
+ operand = (1 << (remainder - 1));
+ }
+ status = *ptr & operand;
+ if (status)
+ *ptr = *ptr & ~(operand);
+ }
+}
+
+int ext4fs_set_inode_bmap(int inode_no, unsigned char *buffer, int index)
+{
+ int i, remainder, status;
+ unsigned char *ptr = buffer;
+ unsigned char operand;
+
+ inode_no -= (index * ext4fs_root->sblock.inodes_per_group);
+ i = inode_no / 8;
+ remainder = inode_no % 8;
+ if (remainder == 0) {
+ ptr = ptr + i - 1;
+ operand = (1 << 7);
+ } else {
+ ptr = ptr + i;
+ operand = (1 << (remainder - 1));
+ }
+ status = *ptr & operand;
+ if (status)
+ return -1;
+
+ *ptr = *ptr | operand;
+
+ return 0;
+}
+
+void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index)
+{
+ int i, remainder, status;
+ unsigned char *ptr = buffer;
+ unsigned char operand;
+
+ inode_no -= (index * ext4fs_root->sblock.inodes_per_group);
+ i = inode_no / 8;
+ remainder = inode_no % 8;
+ if (remainder == 0) {
+ ptr = ptr + i - 1;
+ operand = (1 << 7);
+ } else {
+ ptr = ptr + i;
+ operand = (1 << (remainder - 1));
+ }
+ status = *ptr & operand;
+ if (status)
+ *ptr = *ptr & ~(operand);
+}
+
+int ext4fs_checksum_update(unsigned int i)
+{
+ struct ext2_block_group *desc;
+ struct ext_filesystem *fs = get_fs();
+ __u16 crc = 0;
+
+ desc = (struct ext2_block_group *)&fs->gd[i];
+ if (fs->sb->feature_ro_compat & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) {
+ int offset = offsetof(struct ext2_block_group, bg_checksum);
+
+ crc = ext2fs_crc16(~0, fs->sb->unique_id,
+ sizeof(fs->sb->unique_id));
+ crc = ext2fs_crc16(crc, &i, sizeof(i));
+ crc = ext2fs_crc16(crc, desc, offset);
+ offset += sizeof(desc->bg_checksum); /* skip checksum */
+ assert(offset == sizeof(*desc));
+ }
+
+ return crc;
+}
+
+static int check_void_in_dentry(struct ext2_dirent *dir, char *filename)
+{
+ int dentry_length;
+ int sizeof_void_space;
+ int new_entry_byte_reqd;
+ short padding_factor = 0;
+
+ if (dir->namelen % 4 != 0)
+ padding_factor = 4 - (dir->namelen % 4);
+
+ dentry_length = sizeof(struct ext2_dirent) +
+ dir->namelen + padding_factor;
+ sizeof_void_space = dir->direntlen - dentry_length;
+ if (sizeof_void_space == 0)
+ return 0;
+
+ padding_factor = 0;
+ if (strlen(filename) % 4 != 0)
+ padding_factor = 4 - (strlen(filename) % 4);
+
+ new_entry_byte_reqd = strlen(filename) +
+ sizeof(struct ext2_dirent) + padding_factor;
+ if (sizeof_void_space >= new_entry_byte_reqd) {
+ dir->direntlen = dentry_length;
+ return sizeof_void_space;
+ }
+
+ return 0;
+}
+
+void ext4fs_update_parent_dentry(char *filename, int *p_ino, int file_type)
+{
+ unsigned int *zero_buffer = NULL;
+ char *root_first_block_buffer = NULL;
+ int direct_blk_idx;
+ long int root_blknr;
+ long int first_block_no_of_root = 0;
+ long int previous_blknr = -1;
+ int totalbytes = 0;
+ short int padding_factor = 0;
+ unsigned int new_entry_byte_reqd;
+ unsigned int last_entry_dirlen;
+ int sizeof_void_space = 0;
+ int templength = 0;
+ int inodeno;
+ int status;
+ struct ext_filesystem *fs = get_fs();
+ /* directory entry */
+ struct ext2_dirent *dir;
+ char *ptr = NULL;
+ char *temp_dir = NULL;
+
+ zero_buffer = zalloc(fs->blksz);
+ if (!zero_buffer) {
+ printf("No Memory\n");
+ return;
+ }
+ root_first_block_buffer = zalloc(fs->blksz);
+ if (!root_first_block_buffer) {
+ free(zero_buffer);
+ printf("No Memory\n");
+ return;
+ }
+restart:
+
+ /* read the block no allocated to a file */
+ for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
+ direct_blk_idx++) {
+ root_blknr = read_allocated_block(g_parent_inode,
+ direct_blk_idx);
+ if (root_blknr == 0) {
+ first_block_no_of_root = previous_blknr;
+ break;
+ }
+ previous_blknr = root_blknr;
+ }
+
+ status = ext4fs_devread(first_block_no_of_root
+ * fs->sect_perblk,
+ 0, fs->blksz, root_first_block_buffer);
+ if (status == 0)
+ goto fail;
+
+ if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root))
+ goto fail;
+ dir = (struct ext2_dirent *)root_first_block_buffer;
+ ptr = (char *)dir;
+ totalbytes = 0;
+ while (dir->direntlen > 0) {
+ /*
+ * blocksize-totalbytes because last directory length
+ * i.e. dir->direntlen is free availble space in the
+ * block that means it is a last entry of directory
+ * entry
+ */
+
+ /* traversing the each directory entry */
+ if (fs->blksz - totalbytes == dir->direntlen) {
+ if (strlen(filename) % 4 != 0)
+ padding_factor = 4 - (strlen(filename) % 4);
+
+ new_entry_byte_reqd = strlen(filename) +
+ sizeof(struct ext2_dirent) + padding_factor;
+ padding_factor = 0;
+ /*
+ * update last directory entry length to its
+ * length because we are creating new directory
+ * entry
+ */
+ if (dir->namelen % 4 != 0)
+ padding_factor = 4 - (dir->namelen % 4);
+
+ last_entry_dirlen = dir->namelen +
+ sizeof(struct ext2_dirent) + padding_factor;
+ if ((fs->blksz - totalbytes - last_entry_dirlen) <
+ new_entry_byte_reqd) {
+ printf("1st Block Full:Allocate new block\n");
+
+ if (direct_blk_idx == INDIRECT_BLOCKS - 1) {
+ printf("Directory exceeds limit\n");
+ goto fail;
+ }
+ g_parent_inode->b.blocks.dir_blocks
+ [direct_blk_idx] = ext4fs_get_new_blk_no();
+ if (g_parent_inode->b.blocks.dir_blocks
+ [direct_blk_idx] == -1) {
+ printf("no block left to assign\n");
+ goto fail;
+ }
+ put_ext4(((uint64_t)
+ (g_parent_inode->b.
+ blocks.dir_blocks[direct_blk_idx] *
+ fs->blksz)), zero_buffer, fs->blksz);
+ g_parent_inode->size =
+ g_parent_inode->size + fs->blksz;
+ g_parent_inode->blockcnt =
+ g_parent_inode->blockcnt + fs->sect_perblk;
+ if (ext4fs_put_metadata
+ (root_first_block_buffer,
+ first_block_no_of_root))
+ goto fail;
+ goto restart;
+ }
+ dir->direntlen = last_entry_dirlen;
+ break;
+ }
+
+ templength = dir->direntlen;
+ totalbytes = totalbytes + templength;
+ sizeof_void_space = check_void_in_dentry(dir, filename);
+ if (sizeof_void_space)
+ break;
+
+ dir = (struct ext2_dirent *)((char *)dir + templength);
+ ptr = (char *)dir;
+ }
+
+ /* make a pointer ready for creating next directory entry */
+ templength = dir->direntlen;
+ totalbytes = totalbytes + templength;
+ dir = (struct ext2_dirent *)((char *)dir + templength);
+ ptr = (char *)dir;
+
+ /* get the next available inode number */
+ inodeno = ext4fs_get_new_inode_no();
+ if (inodeno == -1) {
+ printf("no inode left to assign\n");
+ goto fail;
+ }
+ dir->inode = inodeno;
+ if (sizeof_void_space)
+ dir->direntlen = sizeof_void_space;
+ else
+ dir->direntlen = fs->blksz - totalbytes;
+
+ dir->namelen = strlen(filename);
+ dir->filetype = FILETYPE_REG; /* regular file */
+ temp_dir = (char *)dir;
+ temp_dir = temp_dir + sizeof(struct ext2_dirent);
+ memcpy(temp_dir, filename, strlen(filename));
+
+ *p_ino = inodeno;
+
+ /* update or write the 1st block of root inode */
+ if (ext4fs_put_metadata(root_first_block_buffer,
+ first_block_no_of_root))
+ goto fail;
+
+fail:
+ free(zero_buffer);
+ free(root_first_block_buffer);
+}
+
+static int search_dir(struct ext2_inode *parent_inode, char *dirname)
+{
+ int status;
+ int inodeno;
+ int totalbytes;
+ int templength;
+ int direct_blk_idx;
+ long int blknr;
+ int found = 0;
+ char *ptr = NULL;
+ unsigned char *block_buffer = NULL;
+ struct ext2_dirent *dir = NULL;
+ struct ext2_dirent *previous_dir = NULL;
+ struct ext_filesystem *fs = get_fs();
+
+ /* read the block no allocated to a file */
+ for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
+ direct_blk_idx++) {
+ blknr = read_allocated_block(parent_inode, direct_blk_idx);
+ if (blknr == 0)
+ goto fail;
+
+ /* read the blocks of parenet inode */
+ block_buffer = zalloc(fs->blksz);
+ if (!block_buffer)
+ goto fail;
+
+ status = ext4fs_devread(blknr * fs->sect_perblk,
+ 0, fs->blksz, (char *)block_buffer);
+ if (status == 0)
+ goto fail;
+
+ dir = (struct ext2_dirent *)block_buffer;
+ ptr = (char *)dir;
+ totalbytes = 0;
+ while (dir->direntlen >= 0) {
+ /*
+ * blocksize-totalbytes because last directory
+ * length i.e.,*dir->direntlen is free availble
+ * space in the block that means
+ * it is a last entry of directory entry
+ */
+ if (strlen(dirname) == dir->namelen) {
+ if (strncmp(dirname, ptr +
+ sizeof(struct ext2_dirent),
+ dir->namelen) == 0) {
+ previous_dir->direntlen +=
+ dir->direntlen;
+ inodeno = dir->inode;
+ dir->inode = 0;
+ found = 1;
+ break;
+ }
+ }
+
+ if (fs->blksz - totalbytes == dir->direntlen)
+ break;
+
+ /* traversing the each directory entry */
+ templength = dir->direntlen;
+ totalbytes = totalbytes + templength;
+ previous_dir = dir;
+ dir = (struct ext2_dirent *)((char *)dir + templength);
+ ptr = (char *)dir;
+ }
+
+ if (found == 1) {
+ free(block_buffer);
+ block_buffer = NULL;
+ return inodeno;
+ }
+
+ free(block_buffer);
+ block_buffer = NULL;
+ }
+
+fail:
+ free(block_buffer);
+
+ return -1;
+}
+
+static int find_dir_depth(char *dirname)
+{
+ char *token = strtok(dirname, "/");
+ int count = 0;
+ while (token != NULL) {
+ token = strtok(NULL, "/");
+ count++;
+ }
+ return count + 1 + 1;
+ /*
+ * for example for string /home/temp
+ * depth=home(1)+temp(1)+1 extra for NULL;
+ * so count is 4;
+ */
+}
+
+static int parse_path(char **arr, char *dirname)
+{
+ char *token = strtok(dirname, "/");
+ int i = 0;
+
+ /* add root */
+ arr[i] = zalloc(strlen("/") + 1);
+ if (!arr[i])
+ return -ENOMEM;
+
+ arr[i++] = "/";
+
+ /* add each path entry after root */
+ while (token != NULL) {
+ arr[i] = zalloc(strlen(token) + 1);
+ if (!arr[i])
+ return -ENOMEM;
+ memcpy(arr[i++], token, strlen(token));
+ token = strtok(NULL, "/");
+ }
+ arr[i] = NULL;
+
+ return 0;
+}
+
+int ext4fs_iget(int inode_no, struct ext2_inode *inode)
+{
+ if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0)
+ return -1;
+
+ return 0;
+}
+
+/*
+ * Function: ext4fs_get_parent_inode_num
+ * Return Value: inode Number of the parent directory of file/Directory to be
+ * created
+ * dirname : Input parmater, input path name of the file/directory to be created
+ * dname : Output parameter, to be filled with the name of the directory
+ * extracted from dirname
+ */
+int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags)
+{
+ int i;
+ int depth = 0;
+ int matched_inode_no;
+ int result_inode_no = -1;
+ char **ptr = NULL;
+ char *depth_dirname = NULL;
+ char *parse_dirname = NULL;
+ struct ext2_inode *parent_inode = NULL;
+ struct ext2_inode *first_inode = NULL;
+ struct ext2_inode temp_inode;
+
+ if (*dirname != '/') {
+ printf("Please supply Absolute path\n");
+ return -1;
+ }
+
+ /* TODO: input validation make equivalent to linux */
+ depth_dirname = zalloc(strlen(dirname) + 1);
+ if (!depth_dirname)
+ return -ENOMEM;
+
+ memcpy(depth_dirname, dirname, strlen(dirname));
+ depth = find_dir_depth(depth_dirname);
+ parse_dirname = zalloc(strlen(dirname) + 1);
+ if (!parse_dirname)
+ goto fail;
+ memcpy(parse_dirname, dirname, strlen(dirname));
+
+ /* allocate memory for each directory level */
+ ptr = zalloc((depth) * sizeof(char *));
+ if (!ptr)
+ goto fail;
+ if (parse_path(ptr, parse_dirname))
+ goto fail;
+ parent_inode = zalloc(sizeof(struct ext2_inode));
+ if (!parent_inode)
+ goto fail;
+ first_inode = zalloc(sizeof(struct ext2_inode));
+ if (!first_inode)
+ goto fail;
+ memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode));
+ memcpy(first_inode, parent_inode, sizeof(struct ext2_inode));
+ if (flags & F_FILE)
+ result_inode_no = EXT2_ROOT_INO;
+ for (i = 1; i < depth; i++) {
+ matched_inode_no = search_dir(parent_inode, ptr[i]);
+ if (matched_inode_no == -1) {
+ if (ptr[i + 1] == NULL && i == 1) {
+ result_inode_no = EXT2_ROOT_INO;
+ goto end;
+ } else {
+ if (ptr[i + 1] == NULL)
+ break;
+ printf("Invalid path\n");
+ result_inode_no = -1;
+ goto fail;
+ }
+ } else {
+ if (ptr[i + 1] != NULL) {
+ memset(parent_inode, '\0',
+ sizeof(struct ext2_inode));
+ if (ext4fs_iget(matched_inode_no,
+ parent_inode)) {
+ result_inode_no = -1;
+ goto fail;
+ }
+ result_inode_no = matched_inode_no;
+ } else {
+ break;
+ }
+ }
+ }
+
+end:
+ if (i == 1)
+ matched_inode_no = search_dir(first_inode, ptr[i]);
+ else
+ matched_inode_no = search_dir(parent_inode, ptr[i]);
+
+ if (matched_inode_no != -1) {
+ ext4fs_iget(matched_inode_no, &temp_inode);
+ if (temp_inode.mode & S_IFDIR) {
+ printf("It is a Directory\n");
+ result_inode_no = -1;
+ goto fail;
+ }
+ }
+
+ if (strlen(ptr[i]) > 256) {
+ result_inode_no = -1;
+ goto fail;
+ }
+ memcpy(dname, ptr[i], strlen(ptr[i]));
+
+fail:
+ free(depth_dirname);
+ free(parse_dirname);
+ free(ptr);
+ free(parent_inode);
+ free(first_inode);
+
+ return result_inode_no;
+}
+
+static int check_filename(char *filename, unsigned int blknr)
+{
+ unsigned int first_block_no_of_root;
+ int totalbytes = 0;
+ int templength = 0;
+ int status, inodeno;
+ int found = 0;
+ char *root_first_block_buffer = NULL;
+ char *root_first_block_addr = NULL;
+ struct ext2_dirent *dir = NULL;
+ struct ext2_dirent *previous_dir = NULL;
+ char *ptr = NULL;
+ struct ext_filesystem *fs = get_fs();
+
+ /* get the first block of root */
+ first_block_no_of_root = blknr;
+ root_first_block_buffer = zalloc(fs->blksz);
+ if (!root_first_block_buffer)
+ return -ENOMEM;
+ root_first_block_addr = root_first_block_buffer;
+ status = ext4fs_devread(first_block_no_of_root *
+ fs->sect_perblk, 0,
+ fs->blksz, root_first_block_buffer);
+ if (status == 0)
+ goto fail;
+
+ if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root))
+ goto fail;
+ dir = (struct ext2_dirent *)root_first_block_buffer;
+ ptr = (char *)dir;
+ totalbytes = 0;
+ while (dir->direntlen >= 0) {
+ /*
+ * blocksize-totalbytes because last
+ * directory length i.e., *dir->direntlen
+ * is free availble space in the block that
+ * means it is a last entry of directory entry
+ */
+ if (strlen(filename) == dir->namelen) {
+ if (strncmp(filename, ptr + sizeof(struct ext2_dirent),
+ dir->namelen) == 0) {
+ printf("file found deleting\n");
+ previous_dir->direntlen += dir->direntlen;
+ inodeno = dir->inode;
+ dir->inode = 0;
+ found = 1;
+ break;
+ }
+ }
+
+ if (fs->blksz - totalbytes == dir->direntlen)
+ break;
+
+ /* traversing the each directory entry */
+ templength = dir->direntlen;
+ totalbytes = totalbytes + templength;
+ previous_dir = dir;
+ dir = (struct ext2_dirent *)((char *)dir + templength);
+ ptr = (char *)dir;
+ }
+
+
+ if (found == 1) {
+ if (ext4fs_put_metadata(root_first_block_addr,
+ first_block_no_of_root))
+ goto fail;
+ return inodeno;
+ }
+fail:
+ free(root_first_block_buffer);
+
+ return -1;
+}
+
+int ext4fs_filename_check(char *filename)
+{
+ short direct_blk_idx = 0;
+ long int blknr = -1;
+ int inodeno = -1;
+
+ /* read the block no allocated to a file */
+ for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
+ direct_blk_idx++) {
+ blknr = read_allocated_block(g_parent_inode, direct_blk_idx);
+ if (blknr == 0)
+ break;
+ inodeno = check_filename(filename, blknr);
+ if (inodeno != -1)
+ return inodeno;
+ }
+
+ return -1;
+}
+
+long int ext4fs_get_new_blk_no(void)
+{
+ short i;
+ short status;
+ int remainder;
+ unsigned int bg_idx;
+ static int prev_bg_bitmap_index = -1;
+ unsigned int blk_per_grp = ext4fs_root->sblock.blocks_per_group;
+ struct ext_filesystem *fs = get_fs();
+ char *journal_buffer = zalloc(fs->blksz);
+ char *zero_buffer = zalloc(fs->blksz);
+ if (!journal_buffer || !zero_buffer)
+ goto fail;
+ struct ext2_block_group *gd = (struct ext2_block_group *)fs->gdtable;
+
+ if (fs->first_pass_bbmap == 0) {
+ for (i = 0; i < fs->no_blkgrp; i++) {
+ if (gd[i].free_blocks) {
+ if (gd[i].bg_flags & EXT4_BG_BLOCK_UNINIT) {
+ put_ext4(((uint64_t) (gd[i].block_id *
+ fs->blksz)),
+ zero_buffer, fs->blksz);
+ gd[i].bg_flags =
+ gd[i].
+ bg_flags & ~EXT4_BG_BLOCK_UNINIT;
+ memcpy(fs->blk_bmaps[i], zero_buffer,
+ fs->blksz);
+ }
+ fs->curr_blkno =
+ _get_new_blk_no(fs->blk_bmaps[i]);
+ if (fs->curr_blkno == -1)
+ /* if block bitmap is completely fill */
+ continue;
+ fs->curr_blkno = fs->curr_blkno +
+ (i * fs->blksz * 8);
+ fs->first_pass_bbmap++;
+ gd[i].free_blocks--;
+ fs->sb->free_blocks--;
+ status = ext4fs_devread(gd[i].block_id *
+ fs->sect_perblk, 0,
+ fs->blksz,
+ journal_buffer);
+ if (status == 0)
+ goto fail;
+ if (ext4fs_log_journal(journal_buffer,
+ gd[i].block_id))
+ goto fail;
+ goto success;
+ } else {
+ debug("no space left on block group %d\n", i);
+ }
+ }
+
+ goto fail;
+ } else {
+restart:
+ fs->curr_blkno++;
+ /* get the blockbitmap index respective to blockno */
+ if (fs->blksz != 1024) {
+ bg_idx = fs->curr_blkno / blk_per_grp;
+ } else {
+ bg_idx = fs->curr_blkno / blk_per_grp;
+ remainder = fs->curr_blkno % blk_per_grp;
+ if (!remainder)
+ bg_idx--;
+ }
+
+ /*
+ * To skip completely filled block group bitmaps
+ * Optimize the block allocation
+ */
+ if (bg_idx >= fs->no_blkgrp)
+ goto fail;
+
+ if (gd[bg_idx].free_blocks == 0) {
+ debug("block group %u is full. Skipping\n", bg_idx);
+ fs->curr_blkno = fs->curr_blkno + blk_per_grp;
+ fs->curr_blkno--;
+ goto restart;
+ }
+
+ if (gd[bg_idx].bg_flags & EXT4_BG_BLOCK_UNINIT) {
+ memset(zero_buffer, '\0', fs->blksz);
+ put_ext4(((uint64_t) (gd[bg_idx].block_id * fs->blksz)),
+ zero_buffer, fs->blksz);
+ memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz);
+ gd[bg_idx].bg_flags = gd[bg_idx].bg_flags &
+ ~EXT4_BG_BLOCK_UNINIT;
+ }
+
+ if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx],
+ bg_idx) != 0) {
+ debug("going for restart for the block no %ld %u\n",
+ fs->curr_blkno, bg_idx);
+ goto restart;
+ }
+
+ /* journal backup */
+ if (prev_bg_bitmap_index != bg_idx) {
+ memset(journal_buffer, '\0', fs->blksz);
+ status = ext4fs_devread(gd[bg_idx].block_id
+ * fs->sect_perblk,
+ 0, fs->blksz, journal_buffer);
+ if (status == 0)
+ goto fail;
+ if (ext4fs_log_journal(journal_buffer,
+ gd[bg_idx].block_id))
+ goto fail;
+
+ prev_bg_bitmap_index = bg_idx;
+ }
+ gd[bg_idx].free_blocks--;
+ fs->sb->free_blocks--;
+ goto success;
+ }
+success:
+ free(journal_buffer);
+ free(zero_buffer);
+
+ return fs->curr_blkno;
+fail:
+ free(journal_buffer);
+ free(zero_buffer);
+
+ return -1;
+}
+
+int ext4fs_get_new_inode_no(void)
+{
+ short i;
+ short status;
+ unsigned int ibmap_idx;
+ static int prev_inode_bitmap_index = -1;
+ unsigned int inodes_per_grp = ext4fs_root->sblock.inodes_per_group;
+ struct ext_filesystem *fs = get_fs();
+ char *journal_buffer = zalloc(fs->blksz);
+ char *zero_buffer = zalloc(fs->blksz);
+ if (!journal_buffer || !zero_buffer)
+ goto fail;
+ struct ext2_block_group *gd = (struct ext2_block_group *)fs->gdtable;
+
+ if (fs->first_pass_ibmap == 0) {
+ for (i = 0; i < fs->no_blkgrp; i++) {
+ if (gd[i].free_inodes) {
+ if (gd[i].bg_itable_unused != gd[i].free_inodes)
+ gd[i].bg_itable_unused =
+ gd[i].free_inodes;
+ if (gd[i].bg_flags & EXT4_BG_INODE_UNINIT) {
+ put_ext4(((uint64_t)
+ (gd[i].inode_id * fs->blksz)),
+ zero_buffer, fs->blksz);
+ gd[i].bg_flags = gd[i].bg_flags &
+ ~EXT4_BG_INODE_UNINIT;
+ memcpy(fs->inode_bmaps[i],
+ zero_buffer, fs->blksz);
+ }
+ fs->curr_inode_no =
+ _get_new_inode_no(fs->inode_bmaps[i]);
+ if (fs->curr_inode_no == -1)
+ /* if block bitmap is completely fill */
+ continue;
+ fs->curr_inode_no = fs->curr_inode_no +
+ (i * inodes_per_grp);
+ fs->first_pass_ibmap++;
+ gd[i].free_inodes--;
+ gd[i].bg_itable_unused--;
+ fs->sb->free_inodes--;
+ status = ext4fs_devread(gd[i].inode_id *
+ fs->sect_perblk, 0,
+ fs->blksz,
+ journal_buffer);
+ if (status == 0)
+ goto fail;
+ if (ext4fs_log_journal(journal_buffer,
+ gd[i].inode_id))
+ goto fail;
+ goto success;
+ } else
+ debug("no inode left on block group %d\n", i);
+ }
+ goto fail;
+ } else {
+restart:
+ fs->curr_inode_no++;
+ /* get the blockbitmap index respective to blockno */
+ ibmap_idx = fs->curr_inode_no / inodes_per_grp;
+ if (gd[ibmap_idx].bg_flags & EXT4_BG_INODE_UNINIT) {
+ memset(zero_buffer, '\0', fs->blksz);
+ put_ext4(((uint64_t) (gd[ibmap_idx].inode_id *
+ fs->blksz)), zero_buffer,
+ fs->blksz);
+ gd[ibmap_idx].bg_flags =
+ gd[ibmap_idx].bg_flags & ~EXT4_BG_INODE_UNINIT;
+ memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer,
+ fs->blksz);
+ }
+
+ if (ext4fs_set_inode_bmap(fs->curr_inode_no,
+ fs->inode_bmaps[ibmap_idx],
+ ibmap_idx) != 0) {
+ debug("going for restart for the block no %d %u\n",
+ fs->curr_inode_no, ibmap_idx);
+ goto restart;
+ }
+
+ /* journal backup */
+ if (prev_inode_bitmap_index != ibmap_idx) {
+ memset(journal_buffer, '\0', fs->blksz);
+ status = ext4fs_devread(gd[ibmap_idx].inode_id
+ * fs->sect_perblk,
+ 0, fs->blksz, journal_buffer);
+ if (status == 0)
+ goto fail;
+ if (ext4fs_log_journal(journal_buffer,
+ gd[ibmap_idx].inode_id))
+ goto fail;
+ prev_inode_bitmap_index = ibmap_idx;
+ }
+ if (gd[ibmap_idx].bg_itable_unused != gd[ibmap_idx].free_inodes)
+ gd[ibmap_idx].bg_itable_unused =
+ gd[ibmap_idx].free_inodes;
+ gd[ibmap_idx].free_inodes--;
+ gd[ibmap_idx].bg_itable_unused--;
+ fs->sb->free_inodes--;
+ goto success;
+ }
+
+success:
+ free(journal_buffer);
+ free(zero_buffer);
+
+ return fs->curr_inode_no;
+fail:
+ free(journal_buffer);
+ free(zero_buffer);
+
+ return -1;
+
+}
+
+
+static void alloc_single_indirect_block(struct ext2_inode *file_inode,
+ unsigned int *total_remaining_blocks,
+ unsigned int *no_blks_reqd)
+{
+ short i;
+ short status;
+ long int actual_block_no;
+ long int si_blockno;
+ /* si :single indirect */
+ unsigned int *si_buffer = NULL;
+ unsigned int *si_start_addr = NULL;
+ struct ext_filesystem *fs = get_fs();
+
+ if (*total_remaining_blocks != 0) {
+ si_buffer = zalloc(fs->blksz);
+ if (!si_buffer) {
+ printf("No Memory\n");
+ return;
+ }
+ si_start_addr = si_buffer;
+ si_blockno = ext4fs_get_new_blk_no();
+ if (si_blockno == -1) {
+ printf("no block left to assign\n");
+ goto fail;
+ }
+ (*no_blks_reqd)++;
+ debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks);
+
+ status = ext4fs_devread(si_blockno * fs->sect_perblk,
+ 0, fs->blksz, (char *)si_buffer);
+ memset(si_buffer, '\0', fs->blksz);
+ if (status == 0)
+ goto fail;
+
+ for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
+ actual_block_no = ext4fs_get_new_blk_no();
+ if (actual_block_no == -1) {
+ printf("no block left to assign\n");
+ goto fail;
+ }
+ *si_buffer = actual_block_no;
+ debug("SIAB %u: %u\n", *si_buffer,
+ *total_remaining_blocks);
+
+ si_buffer++;
+ (*total_remaining_blocks)--;
+ if (*total_remaining_blocks == 0)
+ break;
+ }
+
+ /* write the block to disk */
+ put_ext4(((uint64_t) (si_blockno * fs->blksz)),
+ si_start_addr, fs->blksz);
+ file_inode->b.blocks.indir_block = si_blockno;
+ }
+fail:
+ free(si_start_addr);
+}
+
+static void alloc_double_indirect_block(struct ext2_inode *file_inode,
+ unsigned int *total_remaining_blocks,
+ unsigned int *no_blks_reqd)
+{
+ short i;
+ short j;
+ short status;
+ long int actual_block_no;
+ /* di:double indirect */
+ long int di_blockno_parent;
+ long int di_blockno_child;
+ unsigned int *di_parent_buffer = NULL;
+ unsigned int *di_child_buff = NULL;
+ unsigned int *di_block_start_addr = NULL;
+ unsigned int *di_child_buff_start = NULL;
+ struct ext_filesystem *fs = get_fs();
+
+ if (*total_remaining_blocks != 0) {
+ /* double indirect parent block connecting to inode */
+ di_blockno_parent = ext4fs_get_new_blk_no();
+ if (di_blockno_parent == -1) {
+ printf("no block left to assign\n");
+ goto fail;
+ }
+ di_parent_buffer = zalloc(fs->blksz);
+ if (!di_parent_buffer)
+ goto fail;
+
+ di_block_start_addr = di_parent_buffer;
+ (*no_blks_reqd)++;
+ debug("DIPB %ld: %u\n", di_blockno_parent,
+ *total_remaining_blocks);
+
+ status = ext4fs_devread(di_blockno_parent *
+ fs->sect_perblk, 0,
+ fs->blksz, (char *)di_parent_buffer);
+ memset(di_parent_buffer, '\0', fs->blksz);
+
+ /*
+ * start:for each double indirect parent
+ * block create one more block
+ */
+ for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
+ di_blockno_child = ext4fs_get_new_blk_no();
+ if (di_blockno_child == -1) {
+ printf("no block left to assign\n");
+ goto fail;
+ }
+ di_child_buff = zalloc(fs->blksz);
+ if (!di_child_buff)
+ goto fail;
+
+ di_child_buff_start = di_child_buff;
+ *di_parent_buffer = di_blockno_child;
+ di_parent_buffer++;
+ (*no_blks_reqd)++;
+ debug("DICB %ld: %u\n", di_blockno_child,
+ *total_remaining_blocks);
+
+ status = ext4fs_devread(di_blockno_child *
+ fs->sect_perblk, 0,
+ fs->blksz,
+ (char *)di_child_buff);
+ memset(di_child_buff, '\0', fs->blksz);
+ /* filling of actual datablocks for each child */
+ for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
+ actual_block_no = ext4fs_get_new_blk_no();
+ if (actual_block_no == -1) {
+ printf("no block left to assign\n");
+ goto fail;
+ }
+ *di_child_buff = actual_block_no;
+ debug("DIAB %ld: %u\n", actual_block_no,
+ *total_remaining_blocks);
+
+ di_child_buff++;
+ (*total_remaining_blocks)--;
+ if (*total_remaining_blocks == 0)
+ break;
+ }
+ /* write the block table */
+ put_ext4(((uint64_t) (di_blockno_child * fs->blksz)),
+ di_child_buff_start, fs->blksz);
+ free(di_child_buff_start);
+ di_child_buff_start = NULL;
+
+ if (*total_remaining_blocks == 0)
+ break;
+ }
+ put_ext4(((uint64_t) (di_blockno_parent * fs->blksz)),
+ di_block_start_addr, fs->blksz);
+ file_inode->b.blocks.double_indir_block = di_blockno_parent;
+ }
+fail:
+ free(di_block_start_addr);
+}
+
+static void alloc_triple_indirect_block(struct ext2_inode *file_inode,
+ unsigned int *total_remaining_blocks,
+ unsigned int *no_blks_reqd)
+{
+ short i;
+ short j;
+ short k;
+ long int actual_block_no;
+ /* ti: Triple Indirect */
+ long int ti_gp_blockno;
+ long int ti_parent_blockno;
+ long int ti_child_blockno;
+ unsigned int *ti_gp_buff = NULL;
+ unsigned int *ti_parent_buff = NULL;
+ unsigned int *ti_child_buff = NULL;
+ unsigned int *ti_gp_buff_start_addr = NULL;
+ unsigned int *ti_pbuff_start_addr = NULL;
+ unsigned int *ti_cbuff_start_addr = NULL;
+ struct ext_filesystem *fs = get_fs();
+ if (*total_remaining_blocks != 0) {
+ /* triple indirect grand parent block connecting to inode */
+ ti_gp_blockno = ext4fs_get_new_blk_no();
+ if (ti_gp_blockno == -1) {
+ printf("no block left to assign\n");
+ goto fail;
+ }
+ ti_gp_buff = zalloc(fs->blksz);
+ if (!ti_gp_buff)
+ goto fail;
+
+ ti_gp_buff_start_addr = ti_gp_buff;
+ (*no_blks_reqd)++;
+ debug("TIGPB %ld: %u\n", ti_gp_blockno,
+ *total_remaining_blocks);
+
+ /* for each 4 byte grand parent entry create one more block */
+ for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
+ ti_parent_blockno = ext4fs_get_new_blk_no();
+ if (ti_parent_blockno == -1) {
+ printf("no block left to assign\n");
+ goto fail;
+ }
+ ti_parent_buff = zalloc(fs->blksz);
+ if (!ti_parent_buff)
+ goto fail;
+
+ ti_pbuff_start_addr = ti_parent_buff;
+ *ti_gp_buff = ti_parent_blockno;
+ ti_gp_buff++;
+ (*no_blks_reqd)++;
+ debug("TIPB %ld: %u\n", ti_parent_blockno,
+ *total_remaining_blocks);
+
+ /* for each 4 byte entry parent create one more block */
+ for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
+ ti_child_blockno = ext4fs_get_new_blk_no();
+ if (ti_child_blockno == -1) {
+ printf("no block left assign\n");
+ goto fail;
+ }
+ ti_child_buff = zalloc(fs->blksz);
+ if (!ti_child_buff)
+ goto fail;
+
+ ti_cbuff_start_addr = ti_child_buff;
+ *ti_parent_buff = ti_child_blockno;
+ ti_parent_buff++;
+ (*no_blks_reqd)++;
+ debug("TICB %ld: %u\n", ti_parent_blockno,
+ *total_remaining_blocks);
+
+ /* fill actual datablocks for each child */
+ for (k = 0; k < (fs->blksz / sizeof(int));
+ k++) {
+ actual_block_no =
+ ext4fs_get_new_blk_no();
+ if (actual_block_no == -1) {
+ printf("no block left\n");
+ goto fail;
+ }
+ *ti_child_buff = actual_block_no;
+ debug("TIAB %ld: %u\n", actual_block_no,
+ *total_remaining_blocks);
+
+ ti_child_buff++;
+ (*total_remaining_blocks)--;
+ if (*total_remaining_blocks == 0)
+ break;
+ }
+ /* write the child block */
+ put_ext4(((uint64_t) (ti_child_blockno *
+ fs->blksz)),
+ ti_cbuff_start_addr, fs->blksz);
+ free(ti_cbuff_start_addr);
+
+ if (*total_remaining_blocks == 0)
+ break;
+ }
+ /* write the parent block */
+ put_ext4(((uint64_t) (ti_parent_blockno * fs->blksz)),
+ ti_pbuff_start_addr, fs->blksz);
+ free(ti_pbuff_start_addr);
+
+ if (*total_remaining_blocks == 0)
+ break;
+ }
+ /* write the grand parent block */
+ put_ext4(((uint64_t) (ti_gp_blockno * fs->blksz)),
+ ti_gp_buff_start_addr, fs->blksz);
+ file_inode->b.blocks.triple_indir_block = ti_gp_blockno;
+ }
+fail:
+ free(ti_gp_buff_start_addr);
+}
+
+void ext4fs_allocate_blocks(struct ext2_inode *file_inode,
+ unsigned int total_remaining_blocks,
+ unsigned int *total_no_of_block)
+{
+ short i;
+ long int direct_blockno;
+ unsigned int no_blks_reqd = 0;
+
+ /* allocation of direct blocks */
+ for (i = 0; i < INDIRECT_BLOCKS; i++) {
+ direct_blockno = ext4fs_get_new_blk_no();
+ if (direct_blockno == -1) {
+ printf("no block left to assign\n");
+ return;
+ }
+ file_inode->b.blocks.dir_blocks[i] = direct_blockno;
+ debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks);
+
+ total_remaining_blocks--;
+ if (total_remaining_blocks == 0)
+ break;
+ }
+
+ alloc_single_indirect_block(file_inode, &total_remaining_blocks,
+ &no_blks_reqd);
+ alloc_double_indirect_block(file_inode, &total_remaining_blocks,
+ &no_blks_reqd);
+ alloc_triple_indirect_block(file_inode, &total_remaining_blocks,
+ &no_blks_reqd);
+ *total_no_of_block += no_blks_reqd;
+}
+
+#endif
+
static struct ext4_extent_header *ext4fs_get_extent_block
(struct ext2_data *data, char *buf,
struct ext4_extent_header *ext_block,