thin-provisioning-tools/thin-provisioning/thin_metadata_size.c

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/*
* Copyright (C) 2013 Red Hat, GmbH
*
* Calculates device-mapper thin privisioning
* metadata device size based on pool, block size and
* maximum expected thin provisioned devices and snapshots.
*
* This file is part of the thin-provisioning-tools source.
*
* thin-provisioning-tools is free software: you can redistribute it
* and/or modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, either version 3 of
* the License, or (at your option) any later version.
*
* thin-provisioning-tools is distributed in the hope that it will be
* useful, but WITHOUT ANY WARRANTY; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with thin-provisioning-tools. If not, see
* <http://www.gnu.org/licenses/>.
*
*/
#include <getopt.h>
#include <libgen.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "version.h"
#include <search.h>
/*----------------------------------------------------------------*/
enum numeric_options { BLOCKSIZE, POOLSIZE, MAXTHINS, NUMERIC, OPT_END};
enum return_units { RETURN_BYTES, RETURN_SECTORS };
enum numeric_type { NO_NUMBER, NUMBER, NUMBER_SHORT, NUMBER_LONG };
typedef unsigned bool;
enum bool_value { false = 0, true = 1};
struct global {
char *prg; /* program name */
/* Unit representations in characters, strings and numeric factors. */
struct {
char *chars;
char **strings;
unsigned long long *factors;
} unit;
/* Command line option properties. */
struct options {
unsigned unit_idx;
char *s[OPT_END];
unsigned long long n[OPT_END];
} options;
};
static void exit_prg(struct global *g, int ret)
{
if (g) {
unsigned u = OPT_END;
while (u--) {
if (g->options.s[u])
free (g->options.s[u]);
}
free(g);
}
exit(ret);
}
static void abort_prg(struct global *g, const char *msg)
{
fprintf(stderr, "%s - %s\n", g ? g->prg : "fatal", msg);
exit_prg(g, 1);
}
static int unit_index(struct global *g, char *unit_string)
{
unsigned len;
if (!unit_string)
return unit_index(g, "sectors");
len = strlen(unit_string);
if (len == 1) {
char *o = strchr(g->unit.chars, *unit_string);
if (o)
return o - g->unit.chars;
} else {
char **s;
for (s = g->unit.strings; *s; s++)
if (!strncmp(*s, unit_string, len))
return s - g->unit.strings;
}
return -1;
}
#define ARRAY_SIZE(a) (sizeof(a)/sizeof(a[0]))
static struct global *init_prg(char *prg_path)
{
unsigned u;
static char *unit_chars = "bskKmMgGtTpPeEzZyY";
static char *unit_strings[] = { "bytes", "sectors",
"kilobytes", "kibibytes", "megabytes", "mebibytes",
"gigabytes", "gibibytes", "terabytes", "tebibytes",
"petabytes", "pebibytes", "exabytes", "ebibytes",
"zetabytes", "zebibytes", "yottabytes", "yobibytes", NULL };
static unsigned long long unit_factors[ARRAY_SIZE(unit_strings) - 1] = { 1, 512, 1024, 1000 };
struct global *r = malloc(sizeof(*r));
if (!r)
abort_prg(r, "failed to allocate global context!");
memset(r, 0, sizeof(*r));
for (u = 4; unit_strings[u]; u += 2) {
unit_factors[u] = unit_factors[u-2] * unit_factors[2];
unit_factors[u+1] = unit_factors[u-1] * unit_factors[3];
}
r->prg = basename(prg_path);
r->unit.chars = unit_chars;
r->unit.strings = unit_strings;
r->unit.factors = unit_factors;
r->options.unit_idx = unit_index(r, NULL);
return r;
}
static unsigned long long bytes_per_sector(struct global *g)
{
return g->unit.factors[unit_index(g, "sectors")];
}
static void check_opts(struct global *g)
{
struct options *o = &g->options;
if (!o->n[BLOCKSIZE])
abort_prg(g, "block size required!");
else if (!o->n[POOLSIZE])
abort_prg(g, "pool size required!");
else if (!o->n[MAXTHINS])
abort_prg(g, "max thins required!");
else if (o->n[BLOCKSIZE] & (o->n[BLOCKSIZE] - 1))
abort_prg(g, "block size must be 2^^N");
else if (o->n[POOLSIZE] <= o->n[BLOCKSIZE])
abort_prg(g, "pool size must be larger than block size");
}
static unsigned long long to_bytes(struct global *g, char *sz, enum return_units unit, int *index)
{
int idx;
unsigned long long r;
char *us = sz;
/* Get pointer to unit identifier. */
us += strspn(sz, "0123456789");
if (*us) {
idx = unit_index(g, us);
if (idx < 0)
abort_prg(g, "Invalid unit specifier!");
*us = 0;
*index = idx;
} else {
idx = unit_index(g, NULL);
us = NULL;
*index = -1;
}
r = atoll(sz) * g->unit.factors[idx];
return (!us || unit == RETURN_SECTORS) ? r / bytes_per_sector(g) : r;
}
static void printf_aligned(struct global *g, char *a, char *b, char *c, bool units, bool mandatory)
{
char buf[80];
strcpy(buf, b);
if (units)
strcat(buf, mandatory ? "{" :"["), strcat(buf, g->unit.chars), strcat(buf, mandatory ? "}" : "]");
printf("\t%-4s%-44s%s\n", a, buf, c);
}
static void help(struct global *g)
{
printf ("Thin Provisioning Metadata Device Size Calculator.\nUsage: %s [options]\n", g->prg);
printf_aligned(g, "-b", "--block-size BLOCKSIZE", "Block size of thin provisioned devices.", true, false);
printf_aligned(g, "-s", "--pool-size SIZE", "Size of pool device.", true, false);
printf_aligned(g, "-m", "--max-thins #MAXTHINS", "Maximum sum of all thin devices and snapshots.", true, false);
printf_aligned(g, "-u", "--unit ", "Output unit specifier.", true, true);
printf_aligned(g, "-n", "--numeric-only [short|long]", "Output numeric value only (optionally with short/long unit identifier).", false, false);
printf_aligned(g, "-h", "--help", "This help.", false, false);
printf_aligned(g, "-V", "--version", "Print thin provisioning tools version.", false, false);
exit_prg(g, 0);
}
static void version(struct global *g)
{
printf("%s\n", THIN_PROVISIONING_TOOLS_VERSION);
exit_prg(g, 1);
}
static void check_unit(struct global *g, char *arg)
{
int idx = unit_index(g, arg);
if (idx < 0)
abort_prg(g, "output unit specifier invalid!");
g->options.unit_idx = idx;
}
static void check_numeric_option(struct global *g, char *arg)
{
if (g->options.n[NUMERIC] != NO_NUMBER)
abort_prg(g, "-n already given!");
g->options.n[NUMERIC] = NUMBER;
if (arg) {
bool unit_long = !strncmp("long", arg, strlen(arg));
if (!*arg || (strncmp("short", arg, strlen(arg)) && !unit_long))
abort_prg(g, "-n invalid option argument");
g->options.n[NUMERIC] = unit_long ? NUMBER_LONG : NUMBER_SHORT;
}
}
static void check_size(struct global *g, enum numeric_options o, char *arg)
{
int idx;
bool valid_index = true;
if (g->options.n[o])
abort_prg(g, "option already given!");
g->options.n[o] = to_bytes(g, arg, o == MAXTHINS ? RETURN_BYTES : RETURN_SECTORS, &idx);
if (idx < 0) {
valid_index = false;
idx = g->options.unit_idx;
}
g->options.s[o] = malloc(strlen(arg) + strlen(g->unit.strings[idx]) + 1);
if (!g->options.s[o])
abort_prg(g, "failed to allocate string!");
strcpy(g->options.s[o], arg);
if (o != MAXTHINS || valid_index)
strcat(g->options.s[o], g->unit.strings[idx]);
}
static void parse_command_line(struct global *g, int argc, char **argv)
{
int c;
static struct option long_options[] = {
{"block-size", required_argument, NULL, 'b' },
{"pool-size", required_argument, NULL, 's' },
{"max-thins", required_argument, NULL, 'm' },
{"unit", required_argument, NULL, 'u' },
{"numeric-only",optional_argument, NULL, 'n' },
{"help", no_argument, NULL, 'h' },
{"version", no_argument, NULL, 'V' },
{NULL, 0, NULL, 0 }
};
while ((c = getopt_long(argc, argv, "b:s:m:u:n::hV", long_options, NULL)) != -1) {
switch (c) {
case 'b':
check_size(g, BLOCKSIZE, optarg);
break;
case 's':
check_size(g, POOLSIZE, optarg);
break;
case 'm':
check_size(g, MAXTHINS, optarg);
break;
case 'u':
check_unit(g, optarg);
break;
case 'n':
check_numeric_option(g, optarg);
break;
case 'h':
help(g); /* exits */
case 'V':
version(g); /* exits */
default:
exit_prg(g, 1);
}
}
check_opts(g);
}
static const unsigned mappings_per_block(void)
{
const struct {
const unsigned node;
const unsigned node_header;
const unsigned entry;
} btree_size = { 4096, 64, 16 };
return (btree_size.node - btree_size.node_header) / btree_size.entry;
}
static void print_precision(struct global *g, double r, unsigned idx)
{
bool full = g->options.n[NUMERIC] == NO_NUMBER;
double rtrunc = truncl(r);
if (full)
printf("%s - ", g->prg);
if (r == rtrunc)
printf("%llu", (unsigned long long) r);
else
printf(r - rtrunc < 1E-2 ? "%0.2e" : "%0.2f", r);
if (full)
printf(" %s", g->unit.strings[idx]);
else if (g->options.n[NUMERIC] > NUMBER) {
if (g->options.n[NUMERIC] == NUMBER_SHORT)
printf("%c", g->unit.chars[idx]);
else
printf("%s", g->unit.strings[idx]);
}
if (full)
printf(" estimated metadata area size for \"--block-size=%s --pool-size=%s --max-thins=%s\"",
g->options.s[BLOCKSIZE], g->options.s[POOLSIZE], g->options.s[MAXTHINS]);
putchar('\n');
}
static void print_estimated_result(struct global *g)
{
double r;
/* double-fold # of nodes, because they aren't fully populated in average */
r = (1.0 + (2 * g->options.n[POOLSIZE] / g->options.n[BLOCKSIZE] / mappings_per_block() + g->options.n[MAXTHINS])); /* in 4k blocks */
r *= 8 * bytes_per_sector(g); /* in bytes! */
r /= g->unit.factors[g->options.unit_idx]; /* in requested unit */
print_precision(g, r, g->options.unit_idx);
}
int main(int argc, char **argv)
{
struct global *g = init_prg(*argv);
parse_command_line(g, argc, argv);
print_estimated_result(g);
exit_prg(g, 0);
return 0; /* Doesn't get here... */
}