IPQ4019, QSDK资源, 开源代码-make-ext4fs-2015-05-01.tar.gz

/* * 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 "ext4_extents.h" #include "allocate.h" #include "ext4fixup.h" #include <sparse/sparse.h> #include <sys/types.h> #include <sys/stat.h> #include <sys/types.h> #include <sys/mman.h> #include <fcntl.h> #include <unistd.h> #if defined(__APPLE__) && defined(__MACH__) #define lseek64 lseek #define off64_t off_t #endif /* The inode block count for a file/directory is in units of 512 byte blocks, * _NOT_ the filesystem block size! */ #define INODE_BLOCK_SIZE 512 #define MAX_EXT4_BLOCK_SIZE 4096 /* The two modes the recurse_dir() can be in */ #define SANITY_CHECK_PASS 1 #define MARK_INODE_NUMS 2 #define UPDATE_INODE_NUMS 3 /* Magic numbers to indicate what state the update process is in */ #define MAGIC_STATE_MARKING_INUMS 0x7000151515565512ll #define MAGIC_STATE_UPDATING_INUMS 0x6121131211735123ll #define MAGIC_STATE_UPDATING_SB 0x15e1715151558477ll /* Internal state variables corresponding to the magic numbers */ #define STATE_UNSET 0 #define STATE_MARKING_INUMS 1 #define STATE_UPDATING_INUMS 2 #define STATE_UPDATING_SB 3 /* Used for automated testing of this programs ability to stop and be restarted wthout error */ static int bail_phase = 0; static int bail_loc = 0; static int bail_count = 0; static int count = 0; /* global flags */ static int verbose = 0; static int no_write = 0; static int new_inodes_per_group = 0; static int no_write_fixup_state = 0; static int compute_new_inum(unsigned int old_inum) { unsigned int group, offset; group = (old_inum - 1) / info.inodes_per_group; offset = (old_inum -1) % info.inodes_per_group; return (group * new_inodes_per_group) + offset + 1; } static int get_fs_fixup_state(int fd) { unsigned long long magic; int ret, len; if (no_write) { return no_write_fixup_state; } lseek64(fd, 0, SEEK_SET); len = read(fd, &magic, sizeof(magic)); if (len != sizeof(magic)) { critical_error("cannot read fixup_state\n"); } switch (magic) { case MAGIC_STATE_MARKING_INUMS: ret = STATE_MARKING_INUMS; break; case MAGIC_STATE_UPDATING_INUMS: ret = STATE_UPDATING_INUMS; break; case MAGIC_STATE_UPDATING_SB: ret = STATE_UPDATING_SB; break; default: ret = STATE_UNSET; } return ret; } static int set_fs_fixup_state(int fd, int state) { unsigned long long magic; struct ext4_super_block sb; int len; if (no_write) { no_write_fixup_state = state; return 0; } switch (state) { case STATE_MARKING_INUMS: magic = MAGIC_STATE_MARKING_INUMS; break; case STATE_UPDATING_INUMS: magic = MAGIC_STATE_UPDATING_INUMS; break; case STATE_UPDATING_SB: magic = MAGIC_STATE_UPDATING_SB; break; case STATE_UNSET: default: magic = 0ll; break; } lseek64(fd, 0, SEEK_SET); len = write(fd, &magic, sizeof(magic)); if (len != sizeof(magic)) { critical_error("cannot write fixup_state\n"); } read_sb(fd, &sb); if (magic) { /* If we are in the process of updating the filesystem, make it unmountable */ sb.s_desc_size |= 1; } else { /* we are done, so make the filesystem mountable again */ sb.s_desc_size &= ~1; } if (!no_write) { write_sb(fd, 1024, &sb); } return 0; } static int read_inode(int fd, unsigned int inum, struct ext4_inode *inode) { unsigned int bg_num, bg_offset; off64_t inode_offset; int len; bg_num = (inum-1) / info.inodes_per_group; bg_offset = (inum-1) % info.inodes_per_group; inode_offset = ((unsigned long long)aux_info.bg_desc[bg_num].bg_inode_table * info.block_size) + (bg_offset * info.inode_size); if (lseek64(fd, inode_offset, SEEK_SET) < 0) { critical_error_errno("failed to seek to inode %d\n", inum); } len=read(fd, inode, sizeof(*inode)); if (len != sizeof(*inode)) { critical_error_errno("failed to read inode %d\n", inum); } return 0; } static int read_block(int fd, unsigned long long block_num, void *block) { off64_t off; unsigned int len; off = block_num * info.block_size; if (lseek64(fd, off, SEEK_SET) , 0) { critical_error_errno("failed to seek to block %lld\n", block_num); } len=read(fd, block, info.block_size); if (len != info.block_size) { critical_error_errno("failed to read block %lld\n", block_num); } return 0; } static int write_block(int fd, unsigned long long block_num, void *block) { off64_t off; unsigned int len; if (no_write) { return 0; } off = block_num * info.block_size; if (lseek64(fd, off, SEEK_SET) < 0) { critical_error_errno("failed to seek to block %lld\n", block_num); } len=write(fd, block, info.block_size); if (len != info.block_size) { critical_error_errno("failed to write block %lld\n", block_num); } return 0; } static void check_inode_bitmap(int fd, unsigned int bg_num) { unsigned int inode_bitmap_block_num; unsigned char block[MAX_EXT4_BLOCK_SIZE]; int i, bitmap_updated = 0; /* Using the bg_num, aux_info.bg_desc[], info.inodes_per_group and * new_inodes_per_group, retrieve the inode bitmap, and make sure * the bits between the old and new size are clear */ inode_bitmap_block_num = aux_info.bg_desc[bg_num].bg_inode_bitmap; read_block(fd, inode_bitmap_block_num, block); for (i = info.inodes_per_group; i < new_inodes_per_group; i++) { if (bitmap_get_bit(block, i)) { bitmap_clear_bit(block, i); bitmap_updated = 1; } } if (bitmap_updated) { if (verbose) { printf("Warning: updated inode bitmap for block group %d\n", bg_num); } write_block(fd, inode_bitmap_block_num, block); } return; } /* Update the superblock and bgdesc of the specified block group */ static int update_superblocks_and_bg_desc(int fd, int state) { off64_t ret; struct ext4_super_block sb; unsigned int num_block_groups, total_new_inodes; unsigned int i; read_sb(fd, &sb); /* Compute how many more inodes are now available */ num_block_groups = DIV_ROUND_UP(aux_info.len_blocks, info.blocks_per_group); total_new_inodes = num_block_groups * (new_inodes_per_group - sb.s_inodes_per_group); if (verbose) { printf("created %d additional inodes\n", total_new_inodes); } /* Update the free inodes count in each block group descriptor */ for (i = 0; i < num_block_groups; i++) { if (state == STATE_UPDATING_SB) { aux_info.bg_desc[i].bg_free_inodes_count += (new_inodes_per_group - sb.s_inodes_per_group); } check_inode_bitmap(fd, i); } /* First some sanity checks */ if ((sb.s_inodes_count + total_new_inodes) != (new_inodes_per_group * num_block_groups)) { critical_error("Failed sanity check on new inode count\n"); } if (new_inodes_per_group % (info.block_size/info.inode_size)) { critical_error("Failed sanity check on new inode per group alignment\n"); } /* Updat