/**
* ext4_has_free_blocks()
* @sbi: in-core super block structure.
* @nblocks: number of needed blocks
*
* Check if filesystem has nblocks free & available for allocation.
* On success return 1, return 0 on failure.
*/
static int ext4_has_free_blocks(struct ext4_sb_info *sbi,
s64 nblocks, unsigned int flags)
{
s64 free_blocks, dirty_blocks, root_blocks;
struct percpu_counter *fbc = &sbi->s_freeblocks_counter;
struct percpu_counter *dbc = &sbi->s_dirtyblocks_counter;
free_blocks = percpu_counter_read_positive(fbc);
dirty_blocks = percpu_counter_read_positive(dbc);
root_blocks = ext4_r_blocks_count(sbi->s_es);
if (free_blocks - (nblocks + root_blocks + dirty_blocks) <
EXT4_FREEBLOCKS_WATERMARK) {
free_blocks = percpu_counter_sum_positive(fbc);
dirty_blocks = percpu_counter_sum_positive(dbc);
}
/* Check whether we have space after
* accounting for current dirty blocks & root reserved blocks.
*/
if (free_blocks >= ((root_blocks + nblocks) + dirty_blocks))
return 1;
/* Hm, nope. Are (enough) root reserved blocks available? */
if (sbi->s_resuid == current_fsuid() ||
((sbi->s_resgid != 0) && in_group_p(sbi->s_resgid)) ||
capable(CAP_SYS_RESOURCE) ||
(flags & EXT4_MB_USE_ROOT_BLOCKS)) {
if (free_blocks >= (nblocks + dirty_blocks))
return 1;
}
return 0;
}
/**
* ext4_has_free_blocks()
* @sbi: in-core super block structure.
* @nblocks: number of needed blocks
*
* Check if filesystem has nblocks free & available for allocation.
* On success return 1, return 0 on failure.
*/
static int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks)
{
s64 free_blocks, dirty_blocks, root_blocks;
#ifdef CONFIG_EXT4_FS_SNAPSHOT_CTL_RESERVE
ext4_fsblk_t snapshot_r_blocks;
handle_t *handle = journal_current_handle();
#endif
struct percpu_counter *fbc = &sbi->s_freeblocks_counter;
struct percpu_counter *dbc = &sbi->s_dirtyblocks_counter;
free_blocks = percpu_counter_read_positive(fbc);
dirty_blocks = percpu_counter_read_positive(dbc);
root_blocks = ext4_r_blocks_count(sbi->s_es);
#ifdef CONFIG_EXT4_FS_SNAPSHOT_CTL_RESERVE
if (handle && sbi->s_active_snapshot) {
snapshot_r_blocks =
le64_to_cpu(sbi->s_es->s_snapshot_r_blocks_count);
/*
* snapshot reserved blocks for COWing to active snapshot
*/
if (free_blocks < snapshot_r_blocks + 1 &&
!IS_COWING(handle)) {
return 0;
}
/*
* mortal users must reserve blocks for both snapshot and
* root user
*/
root_blocks += snapshot_r_blocks;
}
#endif
if (free_blocks - (nblocks + root_blocks + dirty_blocks) <
EXT4_FREEBLOCKS_WATERMARK) {
free_blocks = percpu_counter_sum_positive(fbc);
dirty_blocks = percpu_counter_sum_positive(dbc);
if (dirty_blocks < 0) {
printk(KERN_CRIT "Dirty block accounting "
"went wrong %lld\n",
(long long)dirty_blocks);
}
}
/* Check whether we have space after
* accounting for current dirty blocks & root reserved blocks.
*/
if (free_blocks >= ((root_blocks + nblocks) + dirty_blocks))
return 1;
/* Hm, nope. Are (enough) root reserved blocks available? */
if (sbi->s_resuid == current_fsuid() ||
((sbi->s_resgid != 0) && in_group_p(sbi->s_resgid)) ||
capable(CAP_SYS_RESOURCE)) {
if (free_blocks >= (nblocks + dirty_blocks))
return 1;
}
return 0;
}
/**
* ext4_has_free_blocks()
* @sbi: in-core super block structure.
* @nblocks: number of needed blocks
*
* Check if filesystem has nblocks free & available for allocation.
* On success return 1, return 0 on failure.
*/
int ext4_has_free_blocks(struct ext4_sb_info *sbi, s64 nblocks)
{
s64 free_blocks, dirty_blocks, root_blocks;
struct percpu_counter *fbc = &sbi->s_freeblocks_counter;
struct percpu_counter *dbc = &sbi->s_dirtyblocks_counter;
free_blocks = percpu_counter_read_positive(fbc);
dirty_blocks = percpu_counter_read_positive(dbc);
root_blocks = ext4_r_blocks_count(sbi->s_es);
if (free_blocks - (nblocks + root_blocks + dirty_blocks) <
EXT4_FREEBLOCKS_WATERMARK) {
free_blocks = percpu_counter_sum_positive(fbc);
dirty_blocks = percpu_counter_sum_positive(dbc);
if (dirty_blocks < 0) {
printk(KERN_CRIT "Dirty block accounting "
"went wrong %lld\n",
(long long)dirty_blocks);
}
}
/* Check whether we have space after
* accounting for current dirty blocks & root reserved blocks.
*/
if (free_blocks >= ((root_blocks + nblocks) + dirty_blocks))
return 1;
/* Hm, nope. Are (enough) root reserved blocks available? */
if (sbi->s_resuid == current->fsuid ||
((sbi->s_resgid != 0) && in_group_p(sbi->s_resgid)) ||
capable(CAP_SYS_RESOURCE)) {
if (free_blocks >= (nblocks + dirty_blocks))
return 1;
}
return 0;
}
static void do_reserved_size(char *blk_device, char *fs_type, struct fstab_rec *rec)
{
/* Check for the types of filesystems we know how to check */
if (!strcmp(fs_type, "ext2") || !strcmp(fs_type, "ext3") || !strcmp(fs_type, "ext4")) {
/*
* Some system images do not have tune2fs for licensing reasons
* Detect these and skip reserve blocks.
*/
if (access(TUNE2FS_BIN, X_OK)) {
ERROR("Not running %s on %s (executable not in system image)\n",
TUNE2FS_BIN, blk_device);
} else {
INFO("Running %s on %s\n", TUNE2FS_BIN, blk_device);
int status = 0;
int ret = 0;
unsigned long reserved_blocks = 0;
int fd = TEMP_FAILURE_RETRY(open(blk_device, O_RDONLY | O_CLOEXEC));
if (fd >= 0) {
struct ext4_super_block sb;
ret = read_super_block(fd, &sb);
if (ret < 0) {
ERROR("Can't read '%s' super block: %s\n", blk_device, strerror(errno));
goto out;
}
reserved_blocks = rec->reserved_size / EXT4_BLOCK_SIZE(&sb);
unsigned long reserved_threshold = ext4_blocks_count(&sb) * 0.02;
if (reserved_threshold < reserved_blocks) {
WARNING("Reserved blocks %lu is too large\n", reserved_blocks);
reserved_blocks = reserved_threshold;
}
if (ext4_r_blocks_count(&sb) == reserved_blocks) {
INFO("Have reserved same blocks\n");
goto out;
}
} else {
ERROR("Failed to open '%s': %s\n", blk_device, strerror(errno));
return;
}
char buf[16] = {0};
snprintf(buf, sizeof (buf), "-r %lu", reserved_blocks);
char *tune2fs_argv[] = {
TUNE2FS_BIN,
buf,
blk_device,
};
ret = android_fork_execvp_ext(ARRAY_SIZE(tune2fs_argv), tune2fs_argv,
&status, true, LOG_KLOG | LOG_FILE,
true, NULL, NULL, 0);
if (ret < 0) {
/* No need to check for error in fork, we can't really handle it now */
ERROR("Failed trying to run %s\n", TUNE2FS_BIN);
}
out:
close(fd);
}
}
}
