Denis Vlasenko | c4f623e | 2006-12-26 01:30:59 +0000 | [diff] [blame] | 1 | /* vi: set sw=4 ts=4: */ |
| 2 | /* |
| 3 | * bmove.c --- Move blocks around to make way for a particular |
| 4 | * filesystem structure. |
| 5 | * |
| 6 | * Copyright (C) 1997 Theodore Ts'o. This file may be redistributed |
| 7 | * under the terms of the GNU Public License. |
| 8 | */ |
| 9 | |
| 10 | #include <stdio.h> |
| 11 | #include <string.h> |
| 12 | #if HAVE_UNISTD_H |
| 13 | #include <unistd.h> |
| 14 | #endif |
| 15 | #if HAVE_SYS_TYPES_H |
| 16 | #include <sys/types.h> |
| 17 | #endif |
| 18 | |
| 19 | #include "ext2_fs.h" |
| 20 | #include "ext2fsP.h" |
| 21 | |
| 22 | struct process_block_struct { |
| 23 | ext2_ino_t ino; |
| 24 | struct ext2_inode * inode; |
| 25 | ext2fs_block_bitmap reserve; |
| 26 | ext2fs_block_bitmap alloc_map; |
| 27 | errcode_t error; |
| 28 | char *buf; |
| 29 | int add_dir; |
| 30 | int flags; |
| 31 | }; |
| 32 | |
| 33 | static int process_block(ext2_filsys fs, blk_t *block_nr, |
| 34 | e2_blkcnt_t blockcnt, blk_t ref_block, |
| 35 | int ref_offset, void *priv_data) |
| 36 | { |
| 37 | struct process_block_struct *pb; |
| 38 | errcode_t retval; |
| 39 | int ret; |
| 40 | blk_t block, orig; |
| 41 | |
| 42 | pb = (struct process_block_struct *) priv_data; |
| 43 | block = orig = *block_nr; |
| 44 | ret = 0; |
| 45 | |
| 46 | /* |
| 47 | * Let's see if this is one which we need to relocate |
| 48 | */ |
| 49 | if (ext2fs_test_block_bitmap(pb->reserve, block)) { |
| 50 | do { |
| 51 | if (++block >= fs->super->s_blocks_count) |
| 52 | block = fs->super->s_first_data_block; |
| 53 | if (block == orig) { |
| 54 | pb->error = EXT2_ET_BLOCK_ALLOC_FAIL; |
| 55 | return BLOCK_ABORT; |
| 56 | } |
| 57 | } while (ext2fs_test_block_bitmap(pb->reserve, block) || |
| 58 | ext2fs_test_block_bitmap(pb->alloc_map, block)); |
| 59 | |
| 60 | retval = io_channel_read_blk(fs->io, orig, 1, pb->buf); |
| 61 | if (retval) { |
| 62 | pb->error = retval; |
| 63 | return BLOCK_ABORT; |
| 64 | } |
| 65 | retval = io_channel_write_blk(fs->io, block, 1, pb->buf); |
| 66 | if (retval) { |
| 67 | pb->error = retval; |
| 68 | return BLOCK_ABORT; |
| 69 | } |
| 70 | *block_nr = block; |
| 71 | ext2fs_mark_block_bitmap(pb->alloc_map, block); |
| 72 | ret = BLOCK_CHANGED; |
| 73 | if (pb->flags & EXT2_BMOVE_DEBUG) |
| 74 | printf("ino=%ld, blockcnt=%lld, %d->%d\n", pb->ino, |
| 75 | blockcnt, orig, block); |
| 76 | } |
| 77 | if (pb->add_dir) { |
| 78 | retval = ext2fs_add_dir_block(fs->dblist, pb->ino, |
| 79 | block, (int) blockcnt); |
| 80 | if (retval) { |
| 81 | pb->error = retval; |
| 82 | ret |= BLOCK_ABORT; |
| 83 | } |
| 84 | } |
| 85 | return ret; |
| 86 | } |
| 87 | |
| 88 | errcode_t ext2fs_move_blocks(ext2_filsys fs, |
| 89 | ext2fs_block_bitmap reserve, |
| 90 | ext2fs_block_bitmap alloc_map, |
| 91 | int flags) |
| 92 | { |
| 93 | ext2_ino_t ino; |
| 94 | struct ext2_inode inode; |
| 95 | errcode_t retval; |
| 96 | struct process_block_struct pb; |
| 97 | ext2_inode_scan scan; |
| 98 | char *block_buf; |
| 99 | |
| 100 | retval = ext2fs_open_inode_scan(fs, 0, &scan); |
| 101 | if (retval) |
| 102 | return retval; |
| 103 | |
| 104 | pb.reserve = reserve; |
| 105 | pb.error = 0; |
| 106 | pb.alloc_map = alloc_map ? alloc_map : fs->block_map; |
| 107 | pb.flags = flags; |
| 108 | |
| 109 | retval = ext2fs_get_mem(fs->blocksize * 4, &block_buf); |
| 110 | if (retval) |
| 111 | return retval; |
| 112 | pb.buf = block_buf + fs->blocksize * 3; |
| 113 | |
| 114 | /* |
| 115 | * If GET_DBLIST is set in the flags field, then we should |
| 116 | * gather directory block information while we're doing the |
| 117 | * block move. |
| 118 | */ |
| 119 | if (flags & EXT2_BMOVE_GET_DBLIST) { |
| 120 | ext2fs_free_dblist(fs->dblist); |
| 121 | fs->dblist = NULL; |
| 122 | retval = ext2fs_init_dblist(fs, 0); |
| 123 | if (retval) |
| 124 | return retval; |
| 125 | } |
| 126 | |
| 127 | retval = ext2fs_get_next_inode(scan, &ino, &inode); |
| 128 | if (retval) |
| 129 | return retval; |
| 130 | |
| 131 | while (ino) { |
| 132 | if ((inode.i_links_count == 0) || |
| 133 | !ext2fs_inode_has_valid_blocks(&inode)) |
| 134 | goto next; |
| 135 | |
| 136 | pb.ino = ino; |
| 137 | pb.inode = &inode; |
| 138 | |
| 139 | pb.add_dir = (LINUX_S_ISDIR(inode.i_mode) && |
| 140 | flags & EXT2_BMOVE_GET_DBLIST); |
| 141 | |
| 142 | retval = ext2fs_block_iterate2(fs, ino, 0, block_buf, |
| 143 | process_block, &pb); |
| 144 | if (retval) |
| 145 | return retval; |
| 146 | if (pb.error) |
| 147 | return pb.error; |
| 148 | |
| 149 | next: |
| 150 | retval = ext2fs_get_next_inode(scan, &ino, &inode); |
| 151 | if (retval == EXT2_ET_BAD_BLOCK_IN_INODE_TABLE) |
| 152 | goto next; |
| 153 | } |
| 154 | return 0; |
| 155 | } |