Split out libext4_utils
Change-Id: I12aa52b75607379add2669fddba4cd7dc2bb527f
diff --git a/ext4_utils/ext4_utils.c b/ext4_utils/ext4_utils.c
new file mode 100644
index 0000000..cd82827
--- /dev/null
+++ b/ext4_utils/ext4_utils.c
@@ -0,0 +1,391 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "ext4_utils.h"
+#include "output_file.h"
+#include "backed_block.h"
+#include "uuid.h"
+#include "allocate.h"
+#include "indirect.h"
+#include "extent.h"
+
+#include "ext4.h"
+#include "jbd2.h"
+
+#include <fcntl.h>
+#include <arpa/inet.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+#if defined(__linux__)
+#include <linux/fs.h>
+#elif defined(__APPLE__) && defined(__MACH__)
+#include <sys/disk.h>
+#endif
+
+int force = 0;
+struct fs_info info;
+struct fs_aux_info aux_info;
+
+/* returns 1 if a is a power of b */
+static int is_power_of(int a, int b)
+{
+ while (a > b) {
+ if (a % b)
+ return 0;
+ a /= b;
+ }
+
+ return (a == b) ? 1 : 0;
+}
+
+/* Returns 1 if the bg contains a backup superblock. On filesystems with
+ the sparse_super feature, only block groups 0, 1, and powers of 3, 5,
+ and 7 have backup superblocks. Otherwise, all block groups have backup
+ superblocks */
+int ext4_bg_has_super_block(int bg)
+{
+ /* Without sparse_super, every block group has a superblock */
+ if (!(info.feat_ro_compat & EXT4_FEATURE_RO_COMPAT_SPARSE_SUPER))
+ return 1;
+
+ if (bg == 0 || bg == 1)
+ return 1;
+
+ if (is_power_of(bg, 3) || is_power_of(bg, 5) || is_power_of(bg, 7))
+ return 1;
+
+ return 0;
+}
+
+/* Write the filesystem image to a file */
+void write_ext4_image(const char *filename, int gz)
+{
+ int ret = 0;
+ struct output_file *out = open_output_file(filename, gz);
+ off_t off;
+
+ if (!out)
+ return;
+
+ write_data_block(out, 1024, (u8*)aux_info.sb, 1024);
+
+ write_data_block(out, (aux_info.first_data_block + 1) * info.block_size,
+ (u8*)aux_info.bg_desc,
+ aux_info.bg_desc_blocks * info.block_size);
+
+ for_each_data_block(write_data_block, write_data_file, out);
+
+ write_data_block(out, info.len - 1, (u8*)"", 1);
+
+ close_output_file(out);
+}
+
+/* Compute the rest of the parameters of the filesystem from the basic info */
+void ext4_create_fs_aux_info()
+{
+ aux_info.first_data_block = (info.block_size > 1024) ? 0 : 1;
+ aux_info.len_blocks = info.len / info.block_size;
+ aux_info.inode_table_blocks = DIV_ROUND_UP(info.inodes_per_group * info.inode_size,
+ info.block_size);
+ aux_info.groups = DIV_ROUND_UP(aux_info.len_blocks - aux_info.first_data_block,
+ info.blocks_per_group);
+ aux_info.blocks_per_ind = info.block_size / sizeof(u32);
+ aux_info.blocks_per_dind = aux_info.blocks_per_ind * aux_info.blocks_per_ind;
+ aux_info.blocks_per_tind = aux_info.blocks_per_dind * aux_info.blocks_per_dind;
+
+ aux_info.bg_desc_blocks =
+ DIV_ROUND_UP(aux_info.groups * sizeof(struct ext2_group_desc),
+ info.block_size);
+
+ aux_info.bg_desc_reserve_blocks =
+ DIV_ROUND_UP(aux_info.groups * 1024 * sizeof(struct ext2_group_desc),
+ info.block_size) - aux_info.bg_desc_blocks;
+
+ if (aux_info.bg_desc_reserve_blocks > aux_info.blocks_per_ind)
+ aux_info.bg_desc_reserve_blocks = aux_info.blocks_per_ind;
+
+ aux_info.default_i_flags = EXT4_NOATIME_FL;
+
+ u32 last_group_size = aux_info.len_blocks % info.blocks_per_group;
+ u32 last_header_size = 2 + aux_info.inode_table_blocks;
+ if (ext4_bg_has_super_block(aux_info.groups - 1))
+ last_header_size += 1 + aux_info.bg_desc_blocks +
+ aux_info.bg_desc_reserve_blocks;
+ if (last_group_size > 0 && last_group_size < last_header_size) {
+ aux_info.groups--;
+ aux_info.len_blocks -= last_group_size;
+ }
+
+ aux_info.sb = calloc(info.block_size, 1);
+ if (!aux_info.sb)
+ critical_error_errno("calloc");
+
+ aux_info.bg_desc = calloc(info.block_size, aux_info.bg_desc_blocks);
+ if (!aux_info.bg_desc)
+ critical_error_errno("calloc");
+}
+
+void ext4_free_fs_aux_info()
+{
+ free(aux_info.sb);
+ free(aux_info.bg_desc);
+}
+
+/* Fill in the superblock memory buffer based on the filesystem parameters */
+void ext4_fill_in_sb()
+{
+ unsigned int i;
+ struct ext4_super_block *sb = aux_info.sb;
+
+ sb->s_inodes_count = info.inodes_per_group * aux_info.groups;
+ sb->s_blocks_count_lo = aux_info.len_blocks;
+ sb->s_r_blocks_count_lo = 0;
+ sb->s_free_blocks_count_lo = 0;
+ sb->s_free_inodes_count = 0;
+ sb->s_first_data_block = aux_info.first_data_block;
+ sb->s_log_block_size = log_2(info.block_size / 1024);
+ sb->s_obso_log_frag_size = log_2(info.block_size / 1024);
+ sb->s_blocks_per_group = info.blocks_per_group;
+ sb->s_obso_frags_per_group = info.blocks_per_group;
+ sb->s_inodes_per_group = info.inodes_per_group;
+ sb->s_mtime = 0;
+ sb->s_wtime = 0;
+ sb->s_mnt_count = 0;
+ sb->s_max_mnt_count = 0xFFFF;
+ sb->s_magic = EXT4_SUPER_MAGIC;
+ sb->s_state = EXT4_VALID_FS;
+ sb->s_errors = EXT4_ERRORS_RO;
+ sb->s_minor_rev_level = 0;
+ sb->s_lastcheck = 0;
+ sb->s_checkinterval = 0;
+ sb->s_creator_os = EXT4_OS_LINUX;
+ sb->s_rev_level = EXT4_DYNAMIC_REV;
+ sb->s_def_resuid = EXT4_DEF_RESUID;
+ sb->s_def_resgid = EXT4_DEF_RESGID;
+
+ sb->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
+ sb->s_inode_size = info.inode_size;
+ sb->s_block_group_nr = 0;
+ sb->s_feature_compat = info.feat_compat;
+ sb->s_feature_incompat = info.feat_incompat;
+ sb->s_feature_ro_compat = info.feat_ro_compat;
+ generate_uuid("extandroid/make_ext4fs", info.label, sb->s_uuid);
+ memset(sb->s_volume_name, 0, sizeof(sb->s_volume_name));
+ strncpy(sb->s_volume_name, info.label, sizeof(sb->s_volume_name));
+ memset(sb->s_last_mounted, 0, sizeof(sb->s_last_mounted));
+ sb->s_algorithm_usage_bitmap = 0;
+
+ sb->s_reserved_gdt_blocks = aux_info.bg_desc_reserve_blocks;
+ sb->s_prealloc_blocks = 0;
+ sb->s_prealloc_dir_blocks = 0;
+
+ //memcpy(sb->s_journal_uuid, sb->s_uuid, sizeof(sb->s_journal_uuid));
+ if (info.feat_compat & EXT4_FEATURE_COMPAT_HAS_JOURNAL)
+ sb->s_journal_inum = EXT4_JOURNAL_INO;
+ sb->s_journal_dev = 0;
+ sb->s_last_orphan = 0;
+ sb->s_hash_seed[0] = 0; /* FIXME */
+ sb->s_def_hash_version = DX_HASH_TEA;
+ sb->s_reserved_char_pad = EXT4_JNL_BACKUP_BLOCKS;
+ sb->s_desc_size = sizeof(struct ext2_group_desc);
+ sb->s_default_mount_opts = 0; /* FIXME */
+ sb->s_first_meta_bg = 0;
+ sb->s_mkfs_time = 0;
+ //sb->s_jnl_blocks[17]; /* FIXME */
+
+ sb->s_blocks_count_hi = aux_info.len_blocks >> 32;
+ sb->s_r_blocks_count_hi = 0;
+ sb->s_free_blocks_count_hi = 0;
+ sb->s_min_extra_isize = sizeof(struct ext4_inode) -
+ EXT4_GOOD_OLD_INODE_SIZE;
+ sb->s_want_extra_isize = sizeof(struct ext4_inode) -
+ EXT4_GOOD_OLD_INODE_SIZE;
+ sb->s_flags = 0;
+ sb->s_raid_stride = 0;
+ sb->s_mmp_interval = 0;
+ sb->s_mmp_block = 0;
+ sb->s_raid_stripe_width = 0;
+ sb->s_log_groups_per_flex = 0;
+ sb->s_kbytes_written = 0;
+
+ for (i = 0; i < aux_info.groups; i++) {
+ u64 group_start_block = aux_info.first_data_block + i *
+ info.blocks_per_group;
+ u32 header_size = 0;
+ if (ext4_bg_has_super_block(i)) {
+ if (i != 0) {
+ queue_data_block((u8 *)sb, info.block_size, group_start_block);
+ queue_data_block((u8 *)aux_info.bg_desc,
+ aux_info.bg_desc_blocks * info.block_size,
+ group_start_block + 1);
+ }
+ header_size = 1 + aux_info.bg_desc_blocks + aux_info.bg_desc_reserve_blocks;
+ }
+
+ aux_info.bg_desc[i].bg_block_bitmap = group_start_block + header_size;
+ aux_info.bg_desc[i].bg_inode_bitmap = group_start_block + header_size + 1;
+ aux_info.bg_desc[i].bg_inode_table = group_start_block + header_size + 2;
+
+ aux_info.bg_desc[i].bg_free_blocks_count = sb->s_blocks_per_group;
+ aux_info.bg_desc[i].bg_free_inodes_count = sb->s_inodes_per_group;
+ aux_info.bg_desc[i].bg_used_dirs_count = 0;
+ }
+}
+
+void ext4_create_resize_inode()
+{
+ struct block_allocation *reserve_inode_alloc = create_allocation();
+ u32 reserve_inode_len = 0;
+ unsigned int i;
+
+ struct ext4_inode *inode = get_inode(EXT4_RESIZE_INO);
+ if (inode == NULL) {
+ error("failed to get resize inode");
+ return;
+ }
+
+ for (i = 0; i < aux_info.groups; i++) {
+ if (ext4_bg_has_super_block(i)) {
+ u64 group_start_block = aux_info.first_data_block + i *
+ info.blocks_per_group;
+ u32 reserved_block_start = group_start_block + 1 +
+ aux_info.bg_desc_blocks;
+ u32 reserved_block_len = aux_info.bg_desc_reserve_blocks;
+ append_region(reserve_inode_alloc, reserved_block_start,
+ reserved_block_len, i);
+ reserve_inode_len += reserved_block_len;
+ }
+ }
+
+ inode_attach_resize(inode, reserve_inode_alloc);
+
+ inode->i_mode = S_IFREG | S_IRUSR | S_IWUSR;
+ inode->i_links_count = 1;
+
+ free_alloc(reserve_inode_alloc);
+}
+
+/* Allocate the blocks to hold a journal inode and connect them to the
+ reserved journal inode */
+void ext4_create_journal_inode()
+{
+ struct ext4_inode *inode = get_inode(EXT4_JOURNAL_INO);
+ if (inode == NULL) {
+ error("failed to get journal inode");
+ return;
+ }
+
+ u8 *journal_data = inode_allocate_data_extents(inode,
+ info.journal_blocks * info.block_size,
+ info.block_size);
+ if (!journal_data) {
+ error("failed to allocate extents for journal data");
+ return;
+ }
+
+ inode->i_mode = S_IFREG | S_IRUSR | S_IWUSR;
+ inode->i_links_count = 1;
+
+ journal_superblock_t *jsb = (journal_superblock_t *)journal_data;
+ jsb->s_header.h_magic = htonl(JBD2_MAGIC_NUMBER);
+ jsb->s_header.h_blocktype = htonl(JBD2_SUPERBLOCK_V2);
+ jsb->s_blocksize = htonl(info.block_size);
+ jsb->s_maxlen = htonl(info.journal_blocks);
+ jsb->s_nr_users = htonl(1);
+ jsb->s_first = htonl(1);
+ jsb->s_sequence = htonl(1);
+
+ memcpy(aux_info.sb->s_jnl_blocks, &inode->i_block, sizeof(inode->i_block));
+}
+
+/* Update the number of free blocks and inodes in the filesystem and in each
+ block group */
+void ext4_update_free()
+{
+ unsigned int i;
+
+ for (i = 0; i < aux_info.groups; i++) {
+ u32 bg_free_blocks = get_free_blocks(i);
+ u32 bg_free_inodes = get_free_inodes(i);
+
+ aux_info.bg_desc[i].bg_free_blocks_count = bg_free_blocks;
+ aux_info.sb->s_free_blocks_count_lo += bg_free_blocks;
+
+ aux_info.bg_desc[i].bg_free_inodes_count = bg_free_inodes;
+ aux_info.sb->s_free_inodes_count += bg_free_inodes;
+
+ aux_info.bg_desc[i].bg_used_dirs_count += get_directories(i);
+ }
+}
+
+static u64 get_block_device_size(const char *filename)
+{
+ int fd = open(filename, O_RDONLY);
+ u64 size = 0;
+ int ret;
+
+ if (fd < 0)
+ return 0;
+
+#if defined(__linux__)
+ ret = ioctl(fd, BLKGETSIZE64, &size);
+#elif defined(__APPLE__) && defined(__MACH__)
+ ret = ioctl(fd, DKIOCGETBLOCKCOUNT, &size);
+#else
+ return 0;
+#endif
+
+ close(fd);
+
+ if (ret)
+ return 0;
+
+ return size;
+}
+
+u64 get_file_size(const char *filename)
+{
+ struct stat buf;
+ int ret;
+
+ ret = stat(filename, &buf);
+ if (ret)
+ return 0;
+
+ if (S_ISREG(buf.st_mode))
+ return buf.st_size;
+ else if (S_ISBLK(buf.st_mode))
+ return get_block_device_size(filename);
+ else
+ return 0;
+}
+
+u64 parse_num(const char *arg)
+{
+ char *endptr;
+ u64 num = strtoull(arg, &endptr, 10);
+ if (*endptr == 'k' || *endptr == 'K')
+ num *= 1024LL;
+ else if (*endptr == 'm' || *endptr == 'M')
+ num *= 1024LL * 1024LL;
+ else if (*endptr == 'g' || *endptr == 'G')
+ num *= 1024LL * 1024LL * 1024LL;
+
+ return num;
+}
+