/*
* 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, *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
}