btrfs-progs: fi resize: make output more readable

Make output of 'btrfs filesystem resize' command more readable and
describe the changes in more detail.

Before:
Resize '/mnt' of '1:-1G'

After:
Resize device id 1 (/dev/vdb) from 4.00GiB to 3.00GiB

Issue: #307
Signed-off-by: Sidong Yang <realwakka@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Sidong Yang 2021-02-20 12:41:17 +00:00 committed by David Sterba
parent 0c6e50dddd
commit 78aa1d95dd

View file

@ -28,6 +28,7 @@
#include <linux/limits.h>
#include <linux/version.h>
#include <getopt.h>
#include <limits.h>
#include <btrfsutil.h>
@ -1074,6 +1075,118 @@ static const char * const cmd_filesystem_resize_usage[] = {
NULL
};
static int check_resize_args(const char *amount, const char *path) {
struct btrfs_ioctl_fs_info_args fi_args;
struct btrfs_ioctl_dev_info_args *di_args = NULL;
int ret, i, dev_idx = -1;
u64 devid = 1;
const char *res_str = NULL;
char *devstr = NULL, *sizestr = NULL;
u64 new_size = 0, old_size = 0, diff = 0;
int mod = 0;
char amount_dup[BTRFS_VOL_NAME_MAX];
ret = get_fs_info(path, &fi_args, &di_args);
if (ret) {
error("unable to retrieve fs info");
return 1;
}
if (!fi_args.num_devices) {
error("no devices found");
ret = 1;
goto out;
}
ret = snprintf(amount_dup, BTRFS_VOL_NAME_MAX, "%s", amount);
if (strlen(amount) != ret) {
error("newsize argument is too long");
ret = 1;
goto out;
}
sizestr = amount_dup;
devstr = strchr(sizestr, ':');
if (devstr) {
sizestr = devstr + 1;
*devstr = 0;
devstr = amount_dup;
errno = 0;
devid = strtoull(devstr, NULL, 10);
if (errno) {
error("failed to parse devid %s: %m", devstr);
ret = 1;
goto out;
}
}
dev_idx = -1;
for(i = 0; i < fi_args.num_devices; i++) {
if (di_args[i].devid == devid) {
dev_idx = i;
break;
}
}
if (dev_idx < 0) {
error("cannot find devid: %lld", devid);
ret = 1;
goto out;
}
if (strcmp(sizestr, "max") == 0) {
res_str = "max";
} else {
if (sizestr[0] == '-') {
mod = -1;
sizestr++;
} else if (sizestr[0] == '+') {
mod = 1;
sizestr++;
}
diff = parse_size_from_string(sizestr);
if (!diff) {
error("failed to parse size %s", sizestr);
ret = 1;
goto out;
}
old_size = di_args[dev_idx].total_bytes;
if (mod < 0) {
if (diff > old_size) {
error("current size is %s which is smaller than %s",
pretty_size_mode(old_size, UNITS_DEFAULT),
pretty_size_mode(diff, UNITS_DEFAULT));
ret = 1;
goto out;
}
new_size = old_size - diff;
} else if (mod > 0) {
if (diff > ULLONG_MAX - old_size) {
error("increasing %s is out of range",
pretty_size_mode(diff, UNITS_DEFAULT));
ret = 1;
goto out;
}
new_size = old_size + diff;
}
new_size = round_down(new_size, fi_args.sectorsize);
res_str = pretty_size_mode(new_size, UNITS_DEFAULT);
}
printf("Resize device id %lld (%s) from %s to %s\n", devid,
di_args[dev_idx].path,
pretty_size_mode(di_args[dev_idx].total_bytes, UNITS_DEFAULT),
res_str);
out:
free(di_args);
return 0;
}
static int cmd_filesystem_resize(const struct cmd_struct *cmd,
int argc, char **argv)
{
@ -1134,7 +1247,12 @@ static int cmd_filesystem_resize(const struct cmd_struct *cmd,
return 1;
}
printf("Resize '%s' of '%s'\n", path, amount);
ret = check_resize_args(amount, path);
if (ret != 0) {
close_file_or_dir(fd, dirstream);
return 1;
}
memset(&args, 0, sizeof(args));
strncpy_null(args.name, amount);
res = ioctl(fd, BTRFS_IOC_RESIZE, &args);