Files
libiscsi/examples/iscsi-dd.c
Ronnie Sahlberg ca1e152f2c New example file :
iscsi-dd can be used to copy the content of one iscsi lun onto a different
iscsi lun of the exact same sixe.

This example  illustrates how to "steal" a task structure from a callback
so we can use store it and have it remains valid after the read10 callback
has completed.
It also illustrates the async api of libiscsi for read10/write10.

Initially a number of read10 calls are made asynchronously until the
queue is full.
As each read10 completes and returns data, we issue a write10 to write
that data to the other lun.

As soon as a write10 completes, we "release" the initial read10 task corresponding to what we wrote and issue a new read10 to continue copying the next set of un-read data.

Using the async api, it should be easy to get very high performance and
throughput even from one single thread.
2011-01-23 18:35:58 +11:00

299 lines
8.4 KiB
C

/*
Copyright (C) 2010 by Ronnie Sahlberg <ronniesahlberg@gmail.com>
This program 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 2 of the License, or
(at your option) any later version.
This program 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 this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <poll.h>
#include <popt.h>
#include "iscsi.h"
#include "scsi-lowlevel.h"
char *initiator = "iqn.2010-11.ronnie:iscsi-inq";
int max_in_flight = 50;
int blocks_per_io = 200;
struct client {
int finished;
int in_flight;
struct iscsi_context *src_iscsi;
int src_lun;
int src_blocksize;
uint64_t src_num_blocks;
uint64_t pos;
struct iscsi_context *dst_iscsi;
int dst_lun;
int dst_blocksize;
uint64_t dst_num_blocks;
};
void fill_read_queue(struct client *client);
struct write_task {
struct scsi_task *rt;
struct client *client;
};
void write10_cb(struct iscsi_context *iscsi, int status, void *command_data, void *private_data)
{
struct write_task *wt = (struct write_task *)private_data;
struct scsi_task *task = command_data;
struct client *client = wt->client;
if (status == SCSI_STATUS_CHECK_CONDITION) {
printf("Write10 failed with sense key:%d ascq:%04x\n", task->sense.key, task->sense.ascq);
exit(10);
}
if (status != SCSI_STATUS_GOOD) {
printf("Write10 failed with %s\n", iscsi_get_error(iscsi));
exit(10);
}
client->in_flight--;
fill_read_queue(client);
if ((client->in_flight == 0) && (client->pos == client->src_num_blocks)) {
client->finished = 1;
}
scsi_free_scsi_task(wt->rt);
free(wt);
}
void read10_cb(struct iscsi_context *iscsi, int status, void *command_data, void *private_data)
{
struct client *client = (struct client *)private_data;
struct scsi_task *task = command_data;
struct write_task *wt;
if (status == SCSI_STATUS_CHECK_CONDITION) {
printf("Read10 failed with sense key:%d ascq:%04x\n", task->sense.key, task->sense.ascq);
exit(10);
}
wt = malloc(sizeof(struct write_task));
iscsi_cbdata_steal_scsi_task(task);
wt->rt = task;
wt->client = client;
if (iscsi_write10_async(client->dst_iscsi,
client->dst_lun,
task->datain.data,
task->datain.size,
task->params.read10.lba,
0, 0,
client->dst_blocksize, write10_cb,
wt) != 0) {
printf("failed to send read10 command\n");
exit(10);
}
}
void fill_read_queue(struct client *client)
{
int num_blocks;
while(client->in_flight < max_in_flight && client->pos < client->src_num_blocks) {
client->in_flight++;
num_blocks = client->src_num_blocks - client->pos;
if (num_blocks > blocks_per_io) {
num_blocks = blocks_per_io;
}
if (iscsi_read10_async(client->src_iscsi,
client->src_lun, client->pos,
num_blocks * client->src_blocksize,
client->src_blocksize, read10_cb, client) != 0) {
printf("failed to send read10 command\n");
exit(10);
}
client->pos += num_blocks;
}
}
int main(int argc, const char *argv[])
{
poptContext pc;
const char **extra_argv;
char *src_url = NULL;
char *dst_url = NULL;
struct iscsi_url *iscsi_url;
struct scsi_task *task;
struct scsi_readcapacity10 *rc10;
int extra_argc = 0;
int res;
struct pollfd pfd[2];
struct client client;
struct poptOption popt_options[] = {
POPT_AUTOHELP
{ "initiator-name", 'i', POPT_ARG_STRING, &initiator, 0, "Initiatorname to use", "iqn-name" },
{ "src", 0, POPT_ARG_STRING, &src_url, 0, "SRC lun", "iscsi url" },
{ "dst", 0, POPT_ARG_STRING, &dst_url, 0, "DST lun", "iscsi url" },
POPT_TABLEEND
};
pc = poptGetContext(argv[0], argc, argv, popt_options, POPT_CONTEXT_POSIXMEHARDER);
if ((res = poptGetNextOpt(pc)) < -1) {
fprintf(stderr, "Failed to parse option : %s %s\n",
poptBadOption(pc, 0), poptStrerror(res));
exit(10);
}
extra_argv = poptGetArgs(pc);
poptFreeContext(pc);
if (src_url == NULL) {
fprintf(stderr, "You must specify source url\n");
fprintf(stderr, " --src iscsi://<host>[:<port>]/<target-iqn>/<lun>\n", argv[0]);
exit(10);
}
if (dst_url == NULL) {
fprintf(stderr, "You must specify destination url\n");
fprintf(stderr, " --dst iscsi://<host>[:<port>]/<target-iqn>/<lun>\n", argv[0]);
exit(10);
}
memset(&client, 0, sizeof(client));
client.src_iscsi = iscsi_create_context(initiator);
if (client.src_iscsi == NULL) {
fprintf(stderr, "Failed to create context\n");
exit(10);
}
iscsi_url = iscsi_parse_full_url(client.src_iscsi, src_url);
if (iscsi_url == NULL) {
fprintf(stderr, "Failed to parse URL: %s\n",
iscsi_get_error(client.src_iscsi));
exit(10);
}
iscsi_set_targetname(client.src_iscsi, iscsi_url->target);
iscsi_set_session_type(client.src_iscsi, ISCSI_SESSION_NORMAL);
iscsi_set_header_digest(client.src_iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
if (iscsi_url->user != NULL) {
if (iscsi_set_initiator_username_pwd(client.src_iscsi, iscsi_url->user, iscsi_url->passwd) != 0) {
fprintf(stderr, "Failed to set initiator username and password\n");
exit(10);
}
}
if (iscsi_full_connect_sync(client.src_iscsi, iscsi_url->portal, iscsi_url->lun) != 0) {
fprintf(stderr, "Login Failed. %s\n", iscsi_get_error(client.src_iscsi));
iscsi_destroy_url(iscsi_url);
iscsi_destroy_context(client.src_iscsi);
exit(10);
}
client.src_lun = iscsi_url->lun;
iscsi_destroy_url(iscsi_url);
task = iscsi_readcapacity10_sync(client.src_iscsi, client.src_lun, 0, 0);
if (task == NULL || task->status != SCSI_STATUS_GOOD) {
fprintf(stderr, "failed to send readcapacity command\n");
exit(10);
}
rc10 = scsi_datain_unmarshall(task);
if (rc10 == NULL) {
fprintf(stderr, "failed to unmarshall readcapacity10 data\n");
exit(10);
}
client.src_blocksize = rc10->block_size;
client.src_num_blocks = rc10->lba;
scsi_free_scsi_task(task);
client.dst_iscsi = iscsi_create_context(initiator);
if (client.dst_iscsi == NULL) {
fprintf(stderr, "Failed to create context\n");
exit(10);
}
iscsi_url = iscsi_parse_full_url(client.dst_iscsi, dst_url);
if (iscsi_url == NULL) {
fprintf(stderr, "Failed to parse URL: %s\n",
iscsi_get_error(client.dst_iscsi));
exit(10);
}
iscsi_set_targetname(client.dst_iscsi, iscsi_url->target);
iscsi_set_session_type(client.dst_iscsi, ISCSI_SESSION_NORMAL);
iscsi_set_header_digest(client.dst_iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
if (iscsi_url->user != NULL) {
if (iscsi_set_initiator_username_pwd(client.dst_iscsi, iscsi_url->user, iscsi_url->passwd) != 0) {
fprintf(stderr, "Failed to set initiator username and password\n");
exit(10);
}
}
if (iscsi_full_connect_sync(client.dst_iscsi, iscsi_url->portal, iscsi_url->lun) != 0) {
fprintf(stderr, "Login Failed. %s\n", iscsi_get_error(client.dst_iscsi));
iscsi_destroy_url(iscsi_url);
iscsi_destroy_context(client.dst_iscsi);
exit(10);
}
client.dst_lun = iscsi_url->lun;
iscsi_destroy_url(iscsi_url);
task = iscsi_readcapacity10_sync(client.dst_iscsi, client.dst_lun, 0, 0);
if (task == NULL || task->status != SCSI_STATUS_GOOD) {
fprintf(stderr, "failed to send readcapacity command\n");
exit(10);
}
rc10 = scsi_datain_unmarshall(task);
if (rc10 == NULL) {
fprintf(stderr, "failed to unmarshall readcapacity10 data\n");
exit(10);
}
client.dst_blocksize = rc10->block_size;
client.dst_num_blocks = rc10->lba;
scsi_free_scsi_task(task);
fill_read_queue(&client);
while (client.finished == 0) {
pfd[0].fd = iscsi_get_fd(client.src_iscsi);
pfd[0].events = iscsi_which_events(client.src_iscsi);
pfd[1].fd = iscsi_get_fd(client.dst_iscsi);
pfd[1].events = iscsi_which_events(client.dst_iscsi);
if (poll(&pfd[0], 2, -1) < 0) {
printf("Poll failed");
exit(10);
}
if (iscsi_service(client.src_iscsi, pfd[0].revents) < 0) {
printf("iscsi_service failed with : %s\n", iscsi_get_error(client.src_iscsi));
break;
}
if (iscsi_service(client.dst_iscsi, pfd[1].revents) < 0) {
printf("iscsi_service failed with : %s\n", iscsi_get_error(client.dst_iscsi));
break;
}
}
iscsi_logout_sync(client.src_iscsi);
iscsi_destroy_context(client.src_iscsi);
iscsi_logout_sync(client.dst_iscsi);
iscsi_destroy_context(client.dst_iscsi);
return 0;
}