diff options
Diffstat (limited to 'resize/online.c')
| -rw-r--r-- | resize/online.c | 293 |
1 files changed, 293 insertions, 0 deletions
diff --git a/resize/online.c b/resize/online.c new file mode 100644 index 0000000..eef7c0b --- /dev/null +++ b/resize/online.c @@ -0,0 +1,293 @@ +/* + * online.c --- Do on-line resizing of the ext3 filesystem + * + * Copyright (C) 2006 by Theodore Ts'o + * + * %Begin-Header% + * This file may be redistributed under the terms of the GNU Public + * License. + * %End-Header% + */ + +#include "config.h" +#include "resize2fs.h" +#ifdef HAVE_SYS_IOCTL_H +#include <sys/ioctl.h> +#endif +#include <sys/stat.h> +#include <fcntl.h> + +extern char *program_name; + +#define MAX_32_NUM ((((unsigned long long) 1) << 32) - 1) + +#ifdef __linux__ +static int parse_version_number(const char *s) +{ + int major, minor, rev; + char *endptr; + const char *cp = s; + + if (!s) + return 0; + major = strtol(cp, &endptr, 10); + if (cp == endptr || *endptr != '.') + return 0; + cp = endptr + 1; + minor = strtol(cp, &endptr, 10); + if (cp == endptr || *endptr != '.') + return 0; + cp = endptr + 1; + rev = strtol(cp, &endptr, 10); + if (cp == endptr) + return 0; + return ((((major * 256) + minor) * 256) + rev); +} + +#define VERSION_CODE(a,b,c) (((a) << 16) + ((b) << 8) + (c)) + +#endif + +errcode_t online_resize_fs(ext2_filsys fs, const char *mtpt, + blk64_t *new_size, int flags EXT2FS_ATTR((unused))) +{ +#ifdef __linux__ + struct ext2_new_group_input input; + struct ext4_new_group_input input64; + struct ext2_super_block *sb = fs->super; + unsigned long new_desc_blocks; + ext2_filsys new_fs; + errcode_t retval; + double percent; + dgrp_t i; + blk_t size; + int fd; + int use_old_ioctl = 1; + int no_meta_bg_resize = 0; + int no_resize_ioctl = 0; + + if (getenv("RESIZE2FS_KERNEL_VERSION")) { + char *version_to_emulate = getenv("RESIZE2FS_KERNEL_VERSION"); + int kvers = parse_version_number(version_to_emulate); + + if (kvers < VERSION_CODE(3, 7, 0)) + no_meta_bg_resize = 1; + if (kvers < VERSION_CODE(3, 3, 0)) + no_resize_ioctl = 1; + } + + if (ext2fs_has_feature_sparse_super2(fs->super) && + (access("/sys/fs/ext4/features/sparse_super2", R_OK) != 0)) { + com_err(program_name, 0, _("kernel does not support online " + "resize with sparse_super2")); + exit(1); + } + + printf(_("Filesystem at %s is mounted on %s; " + "on-line resizing required\n"), fs->device_name, mtpt); + + if (*new_size < ext2fs_blocks_count(sb)) { + com_err(program_name, 0, _("On-line shrinking not supported")); + exit(1); + } + + /* + * If the number of descriptor blocks is going to increase, + * the on-line resizing inode must be present. + */ + new_desc_blocks = ext2fs_div_ceil( + ext2fs_div64_ceil(*new_size - + fs->super->s_first_data_block, + EXT2_BLOCKS_PER_GROUP(fs->super)), + EXT2_DESC_PER_BLOCK(fs->super)); + printf("old_desc_blocks = %lu, new_desc_blocks = %lu\n", + fs->desc_blocks, new_desc_blocks); + + /* + * Do error checking to make sure the resize will be successful. + */ + if ((access("/sys/fs/ext4/features/meta_bg_resize", R_OK) != 0) || + no_meta_bg_resize) { + if (!ext2fs_has_feature_resize_inode(fs->super) && + (new_desc_blocks != fs->desc_blocks)) { + com_err(program_name, 0, + _("Filesystem does not support online resizing")); + exit(1); + } + + if (ext2fs_has_feature_resize_inode(fs->super) && + new_desc_blocks > (fs->desc_blocks + + fs->super->s_reserved_gdt_blocks)) { + com_err(program_name, 0, + _("Not enough reserved gdt blocks for resizing")); + exit(1); + } + + if ((ext2fs_blocks_count(sb) > MAX_32_NUM) || + (*new_size > MAX_32_NUM)) { + com_err(program_name, 0, + _("Kernel does not support resizing a file system this large")); + exit(1); + } + } + + fd = open(mtpt, O_RDONLY); + if (fd < 0) { + com_err(program_name, errno, + _("while trying to open mountpoint %s"), mtpt); + exit(1); + } + + if (no_resize_ioctl) { + printf(_("Old resize interface requested.\n")); + } else if (ioctl(fd, EXT4_IOC_RESIZE_FS, new_size)) { + /* + * If kernel does not support EXT4_IOC_RESIZE_FS, use the + * old online resize. Note that the old approach does not + * handle >32 bit file systems + * + * Sigh, if we are running a 32-bit binary on a 64-bit + * kernel (which happens all the time on the MIPS + * architecture in Debian, but can happen on other CPU + * architectures as well) we will get EINVAL returned + * when an ioctl doesn't exist, at least up to Linux + * 3.1. See compat_sys_ioctl() in fs/compat_ioctl.c + * in the kernel sources. This is probably a kernel + * bug, but work around it here. + */ + if ((errno != ENOTTY) && (errno != EINVAL)) { + if (errno == EPERM) + com_err(program_name, 0, + _("Permission denied to resize filesystem")); + else + com_err(program_name, errno, + _("While checking for on-line resizing " + "support")); + exit(1); + } + } else { + close(fd); + return 0; + } + + size = ext2fs_blocks_count(sb); + + if (ioctl(fd, EXT2_IOC_GROUP_EXTEND, &size)) { + if (errno == EPERM) + com_err(program_name, 0, + _("Permission denied to resize filesystem")); + else if (errno == ENOTTY) + com_err(program_name, 0, + _("Kernel does not support online resizing")); + else + com_err(program_name, errno, + _("While checking for on-line resizing support")); + exit(1); + } + + percent = (ext2fs_r_blocks_count(sb) * 100.0) / + ext2fs_blocks_count(sb); + + retval = ext2fs_read_bitmaps(fs); + if (retval) { + close(fd); + return retval; + } + + retval = ext2fs_dup_handle(fs, &new_fs); + if (retval) { + close(fd); + return retval; + } + + /* The current method of adding one block group at a time to a + * mounted filesystem means it is impossible to accommodate the + * flex_bg allocation method of placing the metadata together + * in a single block group. For now we "fix" this issue by + * using the traditional layout for new block groups, where + * each block group is self-contained and contains its own + * bitmap blocks and inode tables. This means we don't get + * the layout advantages of flex_bg in the new block groups, + * but at least it allows on-line resizing to function. + */ + ext2fs_clear_feature_flex_bg(new_fs->super); + retval = adjust_fs_info(new_fs, fs, 0, *new_size); + if (retval) { + close(fd); + return retval; + } + + printf(_("Performing an on-line resize of %s to %llu (%dk) blocks.\n"), + fs->device_name, (unsigned long long) *new_size, + fs->blocksize / 1024); + + size = fs->group_desc_count * sb->s_blocks_per_group + + sb->s_first_data_block; + if (size > *new_size) + size = *new_size; + + if (ioctl(fd, EXT2_IOC_GROUP_EXTEND, &size)) { + com_err(program_name, errno, + _("While trying to extend the last group")); + exit(1); + } + + for (i = fs->group_desc_count; + i < new_fs->group_desc_count; i++) { + input.group = i; + input.block_bitmap = ext2fs_block_bitmap_loc(new_fs, i); + input.inode_bitmap = ext2fs_inode_bitmap_loc(new_fs, i); + input.inode_table = ext2fs_inode_table_loc(new_fs, i); + input.blocks_count = ext2fs_group_blocks_count(new_fs, i); + input.reserved_blocks = (blk_t) (percent * input.blocks_count + / 100.0); + +#if 0 + printf("new block bitmap is at 0x%04x\n", input.block_bitmap); + printf("new inode bitmap is at 0x%04x\n", input.inode_bitmap); + printf("new inode table is at 0x%04x-0x%04x\n", + input.inode_table, + input.inode_table + new_fs->inode_blocks_per_group-1); + printf("new group has %u blocks\n", input.blocks_count); + printf("new group will reserve %d blocks\n", + input.reserved_blocks); + printf("new group has %d free blocks\n", + ext2fs_bg_free_blocks_count(new_fs, i), + printf("new group has %d free inodes (%d blocks)\n", + ext2fs_bg_free_inodes_count(new_fs, i), + new_fs->inode_blocks_per_group); + printf("Adding group #%d\n", input.group); +#endif + + if (use_old_ioctl && + ioctl(fd, EXT2_IOC_GROUP_ADD, &input) == 0) + continue; + else + use_old_ioctl = 0; + + input64.group = input.group; + input64.block_bitmap = input.block_bitmap; + input64.inode_bitmap = input.inode_bitmap; + input64.inode_table = input.inode_table; + input64.blocks_count = input.blocks_count; + input64.reserved_blocks = input.reserved_blocks; + input64.unused = input.unused; + + if (ioctl(fd, EXT4_IOC_GROUP_ADD, &input64) < 0) { + com_err(program_name, errno, + _("While trying to add group #%d"), + input.group); + exit(1); + } + } + + ext2fs_free(new_fs); + close(fd); + + return 0; +#else + printf(_("Filesystem at %s is mounted on %s, and on-line resizing is " + "not supported on this system.\n"), fs->device_name, mtpt); + exit(1); +#endif +} |