diff options
Diffstat (limited to 'ext4_utils/make_ext4fs.c')
| -rw-r--r-- | ext4_utils/make_ext4fs.c | 186 |
1 files changed, 175 insertions, 11 deletions
diff --git a/ext4_utils/make_ext4fs.c b/ext4_utils/make_ext4fs.c index 913a40df..7752e6b9 100644 --- a/ext4_utils/make_ext4fs.c +++ b/ext4_utils/make_ext4fs.c @@ -5,7 +5,7 @@ * 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 + * 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, @@ -79,6 +79,13 @@ #endif +#define MAX_PATH 4096 +#define MAX_BLK_MAPPING_STR 1000 + +const int blk_file_major_ver = 1; +const int blk_file_minor_ver = 0; +const char *blk_file_header_fmt = "Base EXT4 version %d.%d"; + /* TODO: Not implemented: Allocating blocks in the same block group as the file inode Hash or binary tree directories @@ -91,7 +98,7 @@ static int filter_dot(const struct dirent *d) } static u32 build_default_directory_structure(const char *dir_path, - struct selabel_handle *sehnd) + struct selabel_handle *sehnd) { u32 inode; u32 root_inode; @@ -425,8 +432,8 @@ int make_ext4fs_sparse_fd_directory(int fd, long long len, info.len = len; return make_ext4fs_internal(fd, directory, NULL, mountpoint, NULL, - 0, 1, 0, 0, 0, - sehnd, 0, -1, NULL); + 0, 1, 0, 0, 0, + sehnd, 0, -1, NULL, NULL, NULL); } int make_ext4fs(const char *filename, long long len, @@ -436,8 +443,8 @@ int make_ext4fs(const char *filename, long long len, } int make_ext4fs_directory(const char *filename, long long len, - const char *mountpoint, struct selabel_handle *sehnd, - const char *directory) + const char *mountpoint, struct selabel_handle *sehnd, + const char *directory) { int fd; int status; @@ -452,8 +459,8 @@ int make_ext4fs_directory(const char *filename, long long len, } status = make_ext4fs_internal(fd, directory, NULL, mountpoint, NULL, - 0, 0, 0, 1, 0, - sehnd, 0, -1, NULL); + 0, 0, 0, 1, 0, + sehnd, 0, -1, NULL, NULL, NULL); close(fd); return status; @@ -519,17 +526,158 @@ static char *canonicalize_rel_slashes(const char *str) return canonicalize_slashes(str, false); } +static int compare_chunks(const void* chunk1, const void* chunk2) { + struct region* c1 = (struct region*) chunk1; + struct region* c2 = (struct region*) chunk2; + return c1->block - c2->block; +} + +static int get_block_group(u32 block) { + int i, group = 0; + for(i = 0; i < aux_info.groups; i++) { + if (block >= aux_info.bgs[i].first_block) + group = i; + else + break; + } + return group; +} + +static void extract_base_fs_allocations(const char *directory, const char *mountpoint, + FILE* base_alloc_file_in) { +#define err_msg "base file badly formatted" + // FORMAT Version 1.0: filename blk_mapping + const char *base_alloc_file_in_format = "%s %s"; + const int base_file_format_param_count = 2; + + char stored_file_name[MAX_PATH], real_file_name[MAX_PATH], file_map[MAX_BLK_MAPPING_STR]; + struct block_allocation *fs_alloc; + struct block_group_info *bgs = aux_info.bgs; + int i, major_version = 0, minor_version = 0; + char *base_file_line = NULL; + size_t base_file_line_len = 0; + + printf("[v%d.%d] Generating an Incremental EXT4 image\n", + blk_file_major_ver, blk_file_minor_ver); + if (base_fs_allocations == NULL) + base_fs_allocations = create_allocation(); + fs_alloc = base_fs_allocations; + + fscanf(base_alloc_file_in, blk_file_header_fmt, &major_version, &minor_version); + if (major_version == 0) { + critical_error("Invalid base file"); + } + + if (major_version != blk_file_major_ver) { + critical_error("Incompatible base file: version required is %d.X", + blk_file_major_ver); + } + + if (minor_version < blk_file_minor_ver) { + critical_error("Incompatible base file: version required is %d.%d or above", + blk_file_major_ver, blk_file_minor_ver); + } + + while (getline(&base_file_line, &base_file_line_len, base_alloc_file_in) != -1) { + if (sscanf(base_file_line, base_alloc_file_in_format, &stored_file_name, &file_map) + != base_file_format_param_count) { + continue; + } + if (strlen(stored_file_name) < strlen(mountpoint)) { + continue; + } + snprintf(real_file_name, MAX_PATH, "%s%s", directory, stored_file_name + strlen(mountpoint)); + if (!access(real_file_name, R_OK)) { + char *block_range, *end_string; + int real_file_fd; + u32 start_block, end_block, block_file_size; + u32 real_file_block_size; + + real_file_fd = open(real_file_name, O_RDONLY); + if (real_file_fd == -1) { + critical_error(err_msg); + } + real_file_block_size = get_file_size(real_file_fd); + close(real_file_fd); + real_file_block_size = DIV_ROUND_UP(real_file_block_size, info.block_size); + fs_alloc->filename = strdup(real_file_name); + block_range = strtok_r(file_map, ",", &end_string); + while (block_range && real_file_block_size) { + int block_group; + char *range, *end_token = NULL; + range = strtok_r(block_range, "-", &end_token); + if (!range) { + critical_error(err_msg); + } + start_block = parse_num(range); + range = strtok_r(NULL, "-", &end_token); + if (!range) { + end_block = start_block; + } else { + end_block = parse_num(range); + } + block_file_size = end_block - start_block + 1; + if (block_file_size > real_file_block_size) { + block_file_size = real_file_block_size; + } + // Assummption is that allocations are within the same block group + block_group = get_block_group(start_block); + if (block_group != get_block_group(end_block)) { + critical_error("base file allocation's end block is in a different " + "block group than start block. did you change fs params?"); + } + block_range = strtok_r(NULL, ",", &end_string); + append_region(fs_alloc, start_block, block_file_size, block_group); + reserve_bg_chunk(block_group, start_block - bgs[block_group].first_block, block_file_size); + real_file_block_size -= block_file_size; + } + if (reserve_blocks_for_allocation(fs_alloc) < 0) + critical_error("failed to reserve base fs allocation"); + fs_alloc->next = create_allocation(); + fs_alloc = fs_alloc->next; + } + } + + for (i = 0; i < aux_info.groups; i++) { + qsort(bgs[i].chunks, bgs[i].chunk_count, sizeof(struct region), compare_chunks); + } + + free(base_file_line); + +#undef err_msg +} + +void generate_base_alloc_file_out(FILE* base_alloc_file_out, char* dir, char* mountpoint, + struct block_allocation* p) +{ + size_t dirlen = dir ? strlen(dir) : 0; + fprintf(base_alloc_file_out, blk_file_header_fmt, blk_file_major_ver, blk_file_minor_ver); + fputc('\n', base_alloc_file_out); + while (p) { + if (dir && strncmp(p->filename, dir, dirlen) == 0) { + // substitute mountpoint for the leading directory in the filename, in the output file + fprintf(base_alloc_file_out, "%s%s", mountpoint, p->filename + dirlen); + } else { + fprintf(base_alloc_file_out, "%s", p->filename); + } + print_blocks(base_alloc_file_out, p, ','); + struct block_allocation* pn = p->next; + p = pn; + } +} + int make_ext4fs_internal(int fd, const char *_directory, const char *_target_out_directory, const char *_mountpoint, fs_config_func_t fs_config_func, int gzip, int sparse, int crc, int wipe, int real_uuid, struct selabel_handle *sehnd, int verbose, time_t fixed_time, - FILE* block_list_file) + FILE* block_list_file, FILE* base_alloc_file_in, FILE* base_alloc_file_out) { u32 root_inode_num; u16 root_mode; char *mountpoint; char *directory = NULL; char *target_out_directory = NULL; + struct block_allocation* p; if (setjmp(setjmp_env)) return EXIT_FAILURE; /* Handle a call to longjmp() */ @@ -627,6 +775,9 @@ int make_ext4fs_internal(int fd, const char *_directory, const char *_target_out ext4_fill_in_sb(real_uuid); + if (base_alloc_file_in) { + extract_base_fs_allocations(directory, mountpoint, base_alloc_file_in); + } if (reserve_inodes(0, 10) == EXT4_ALLOCATE_FAILED) error("failed to reserve first 10 inodes"); @@ -670,6 +821,8 @@ int make_ext4fs_internal(int fd, const char *_directory, const char *_target_out ext4_update_free(); + // TODO: Consider migrating the OTA tools to the new base alloc file format + // used for generating incremental images (see go/incremental-ext4) if (block_list_file) { size_t dirlen = directory ? strlen(directory) : 0; struct block_allocation* p = get_saved_allocation_chain(); @@ -680,13 +833,17 @@ int make_ext4fs_internal(int fd, const char *_directory, const char *_target_out } else { fprintf(block_list_file, "%s", p->filename); } - print_blocks(block_list_file, p); + print_blocks(block_list_file, p, ' '); struct block_allocation* pn = p->next; - free_alloc(p); p = pn; } } + if (base_alloc_file_out) { + struct block_allocation* p = get_saved_allocation_chain(); + generate_base_alloc_file_out(base_alloc_file_out, directory, mountpoint, p); + } + printf("Created filesystem with %d/%d inodes and %d/%d blocks\n", aux_info.sb->s_inodes_count - aux_info.sb->s_free_inodes_count, aux_info.sb->s_inodes_count, @@ -702,6 +859,13 @@ int make_ext4fs_internal(int fd, const char *_directory, const char *_target_out sparse_file_destroy(ext4_sparse_file); ext4_sparse_file = NULL; + p = get_saved_allocation_chain(); + while (p) { + struct block_allocation* pn = p->next; + free_alloc(p); + p = pn; + } + free(mountpoint); free(directory); |