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-rw-r--r--block/iscsi.c591
1 files changed, 591 insertions, 0 deletions
diff --git a/block/iscsi.c b/block/iscsi.c
new file mode 100644
index 0000000000..938c568071
--- /dev/null
+++ b/block/iscsi.c
@@ -0,0 +1,591 @@
+/*
+ * QEMU Block driver for iSCSI images
+ *
+ * Copyright (c) 2010-2011 Ronnie Sahlberg <ronniesahlberg@gmail.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "config-host.h"
+
+#include <poll.h>
+#include "qemu-common.h"
+#include "qemu-error.h"
+#include "block_int.h"
+#include "trace.h"
+
+#include <iscsi/iscsi.h>
+#include <iscsi/scsi-lowlevel.h>
+
+
+typedef struct IscsiLun {
+ struct iscsi_context *iscsi;
+ int lun;
+ int block_size;
+ unsigned long num_blocks;
+} IscsiLun;
+
+typedef struct IscsiAIOCB {
+ BlockDriverAIOCB common;
+ QEMUIOVector *qiov;
+ QEMUBH *bh;
+ IscsiLun *iscsilun;
+ struct scsi_task *task;
+ uint8_t *buf;
+ int status;
+ int canceled;
+ size_t read_size;
+ size_t read_offset;
+} IscsiAIOCB;
+
+struct IscsiTask {
+ IscsiLun *iscsilun;
+ BlockDriverState *bs;
+ int status;
+ int complete;
+};
+
+static void
+iscsi_abort_task_cb(struct iscsi_context *iscsi, int status, void *command_data,
+ void *private_data)
+{
+}
+
+static void
+iscsi_aio_cancel(BlockDriverAIOCB *blockacb)
+{
+ IscsiAIOCB *acb = (IscsiAIOCB *)blockacb;
+ IscsiLun *iscsilun = acb->iscsilun;
+
+ acb->common.cb(acb->common.opaque, -ECANCELED);
+ acb->canceled = 1;
+
+ /* send a task mgmt call to the target to cancel the task on the target */
+ iscsi_task_mgmt_abort_task_async(iscsilun->iscsi, acb->task,
+ iscsi_abort_task_cb, NULL);
+
+ /* then also cancel the task locally in libiscsi */
+ iscsi_scsi_task_cancel(iscsilun->iscsi, acb->task);
+}
+
+static AIOPool iscsi_aio_pool = {
+ .aiocb_size = sizeof(IscsiAIOCB),
+ .cancel = iscsi_aio_cancel,
+};
+
+
+static void iscsi_process_read(void *arg);
+static void iscsi_process_write(void *arg);
+
+static int iscsi_process_flush(void *arg)
+{
+ IscsiLun *iscsilun = arg;
+
+ return iscsi_queue_length(iscsilun->iscsi) > 0;
+}
+
+static void
+iscsi_set_events(IscsiLun *iscsilun)
+{
+ struct iscsi_context *iscsi = iscsilun->iscsi;
+
+ qemu_aio_set_fd_handler(iscsi_get_fd(iscsi), iscsi_process_read,
+ (iscsi_which_events(iscsi) & POLLOUT)
+ ? iscsi_process_write : NULL,
+ iscsi_process_flush, NULL, iscsilun);
+}
+
+static void
+iscsi_process_read(void *arg)
+{
+ IscsiLun *iscsilun = arg;
+ struct iscsi_context *iscsi = iscsilun->iscsi;
+
+ iscsi_service(iscsi, POLLIN);
+ iscsi_set_events(iscsilun);
+}
+
+static void
+iscsi_process_write(void *arg)
+{
+ IscsiLun *iscsilun = arg;
+ struct iscsi_context *iscsi = iscsilun->iscsi;
+
+ iscsi_service(iscsi, POLLOUT);
+ iscsi_set_events(iscsilun);
+}
+
+
+static int
+iscsi_schedule_bh(QEMUBHFunc *cb, IscsiAIOCB *acb)
+{
+ acb->bh = qemu_bh_new(cb, acb);
+ if (!acb->bh) {
+ error_report("oom: could not create iscsi bh");
+ return -EIO;
+ }
+
+ qemu_bh_schedule(acb->bh);
+ return 0;
+}
+
+static void
+iscsi_readv_writev_bh_cb(void *p)
+{
+ IscsiAIOCB *acb = p;
+
+ qemu_bh_delete(acb->bh);
+
+ if (acb->canceled == 0) {
+ acb->common.cb(acb->common.opaque, acb->status);
+ }
+
+ qemu_aio_release(acb);
+}
+
+
+static void
+iscsi_aio_write10_cb(struct iscsi_context *iscsi, int status,
+ void *command_data, void *opaque)
+{
+ IscsiAIOCB *acb = opaque;
+
+ trace_iscsi_aio_write10_cb(iscsi, status, acb, acb->canceled);
+
+ g_free(acb->buf);
+
+ if (acb->canceled != 0) {
+ qemu_aio_release(acb);
+ scsi_free_scsi_task(acb->task);
+ acb->task = NULL;
+ return;
+ }
+
+ acb->status = 0;
+ if (status < 0) {
+ error_report("Failed to write10 data to iSCSI lun. %s",
+ iscsi_get_error(iscsi));
+ acb->status = -EIO;
+ }
+
+ iscsi_schedule_bh(iscsi_readv_writev_bh_cb, acb);
+ scsi_free_scsi_task(acb->task);
+ acb->task = NULL;
+}
+
+static int64_t sector_qemu2lun(int64_t sector, IscsiLun *iscsilun)
+{
+ return sector * BDRV_SECTOR_SIZE / iscsilun->block_size;
+}
+
+static BlockDriverAIOCB *
+iscsi_aio_writev(BlockDriverState *bs, int64_t sector_num,
+ QEMUIOVector *qiov, int nb_sectors,
+ BlockDriverCompletionFunc *cb,
+ void *opaque)
+{
+ IscsiLun *iscsilun = bs->opaque;
+ struct iscsi_context *iscsi = iscsilun->iscsi;
+ IscsiAIOCB *acb;
+ size_t size;
+ int fua = 0;
+
+ /* set FUA on writes when cache mode is write through */
+ if (!(bs->open_flags & BDRV_O_CACHE_WB)) {
+ fua = 1;
+ }
+
+ acb = qemu_aio_get(&iscsi_aio_pool, bs, cb, opaque);
+ trace_iscsi_aio_writev(iscsi, sector_num, nb_sectors, opaque, acb);
+
+ acb->iscsilun = iscsilun;
+ acb->qiov = qiov;
+
+ acb->canceled = 0;
+
+ /* XXX we should pass the iovec to write10 to avoid the extra copy */
+ /* this will allow us to get rid of 'buf' completely */
+ size = nb_sectors * BDRV_SECTOR_SIZE;
+ acb->buf = g_malloc(size);
+ qemu_iovec_to_buffer(acb->qiov, acb->buf);
+ acb->task = iscsi_write10_task(iscsi, iscsilun->lun, acb->buf, size,
+ sector_qemu2lun(sector_num, iscsilun),
+ fua, 0, iscsilun->block_size,
+ iscsi_aio_write10_cb, acb);
+ if (acb->task == NULL) {
+ error_report("iSCSI: Failed to send write10 command. %s",
+ iscsi_get_error(iscsi));
+ g_free(acb->buf);
+ qemu_aio_release(acb);
+ return NULL;
+ }
+
+ iscsi_set_events(iscsilun);
+
+ return &acb->common;
+}
+
+static void
+iscsi_aio_read10_cb(struct iscsi_context *iscsi, int status,
+ void *command_data, void *opaque)
+{
+ IscsiAIOCB *acb = opaque;
+
+ trace_iscsi_aio_read10_cb(iscsi, status, acb, acb->canceled);
+
+ if (acb->canceled != 0) {
+ qemu_aio_release(acb);
+ scsi_free_scsi_task(acb->task);
+ acb->task = NULL;
+ return;
+ }
+
+ acb->status = 0;
+ if (status != 0) {
+ error_report("Failed to read10 data from iSCSI lun. %s",
+ iscsi_get_error(iscsi));
+ acb->status = -EIO;
+ }
+
+ iscsi_schedule_bh(iscsi_readv_writev_bh_cb, acb);
+ scsi_free_scsi_task(acb->task);
+ acb->task = NULL;
+}
+
+static BlockDriverAIOCB *
+iscsi_aio_readv(BlockDriverState *bs, int64_t sector_num,
+ QEMUIOVector *qiov, int nb_sectors,
+ BlockDriverCompletionFunc *cb,
+ void *opaque)
+{
+ IscsiLun *iscsilun = bs->opaque;
+ struct iscsi_context *iscsi = iscsilun->iscsi;
+ IscsiAIOCB *acb;
+ size_t qemu_read_size, lun_read_size;
+ int i;
+
+ qemu_read_size = BDRV_SECTOR_SIZE * (size_t)nb_sectors;
+
+ acb = qemu_aio_get(&iscsi_aio_pool, bs, cb, opaque);
+ trace_iscsi_aio_readv(iscsi, sector_num, nb_sectors, opaque, acb);
+
+ acb->iscsilun = iscsilun;
+ acb->qiov = qiov;
+
+ acb->canceled = 0;
+ acb->read_size = qemu_read_size;
+ acb->buf = NULL;
+
+ /* If LUN blocksize is bigger than BDRV_BLOCK_SIZE a read from QEMU
+ * may be misaligned to the LUN, so we may need to read some extra
+ * data.
+ */
+ acb->read_offset = 0;
+ if (iscsilun->block_size > BDRV_SECTOR_SIZE) {
+ uint64_t bdrv_offset = BDRV_SECTOR_SIZE * sector_num;
+
+ acb->read_offset = bdrv_offset % iscsilun->block_size;
+ }
+
+ lun_read_size = (qemu_read_size + iscsilun->block_size
+ + acb->read_offset - 1)
+ / iscsilun->block_size * iscsilun->block_size;
+ acb->task = iscsi_read10_task(iscsi, iscsilun->lun,
+ sector_qemu2lun(sector_num, iscsilun),
+ lun_read_size, iscsilun->block_size,
+ iscsi_aio_read10_cb, acb);
+ if (acb->task == NULL) {
+ error_report("iSCSI: Failed to send read10 command. %s",
+ iscsi_get_error(iscsi));
+ qemu_aio_release(acb);
+ return NULL;
+ }
+
+ for (i = 0; i < acb->qiov->niov; i++) {
+ scsi_task_add_data_in_buffer(acb->task,
+ acb->qiov->iov[i].iov_len,
+ acb->qiov->iov[i].iov_base);
+ }
+
+ iscsi_set_events(iscsilun);
+
+ return &acb->common;
+}
+
+
+static void
+iscsi_synccache10_cb(struct iscsi_context *iscsi, int status,
+ void *command_data, void *opaque)
+{
+ IscsiAIOCB *acb = opaque;
+
+ if (acb->canceled != 0) {
+ qemu_aio_release(acb);
+ scsi_free_scsi_task(acb->task);
+ acb->task = NULL;
+ return;
+ }
+
+ acb->status = 0;
+ if (status < 0) {
+ error_report("Failed to sync10 data on iSCSI lun. %s",
+ iscsi_get_error(iscsi));
+ acb->status = -EIO;
+ }
+
+ iscsi_schedule_bh(iscsi_readv_writev_bh_cb, acb);
+ scsi_free_scsi_task(acb->task);
+ acb->task = NULL;
+}
+
+static BlockDriverAIOCB *
+iscsi_aio_flush(BlockDriverState *bs,
+ BlockDriverCompletionFunc *cb, void *opaque)
+{
+ IscsiLun *iscsilun = bs->opaque;
+ struct iscsi_context *iscsi = iscsilun->iscsi;
+ IscsiAIOCB *acb;
+
+ acb = qemu_aio_get(&iscsi_aio_pool, bs, cb, opaque);
+
+ acb->iscsilun = iscsilun;
+ acb->canceled = 0;
+
+ acb->task = iscsi_synchronizecache10_task(iscsi, iscsilun->lun,
+ 0, 0, 0, 0,
+ iscsi_synccache10_cb,
+ acb);
+ if (acb->task == NULL) {
+ error_report("iSCSI: Failed to send synchronizecache10 command. %s",
+ iscsi_get_error(iscsi));
+ qemu_aio_release(acb);
+ return NULL;
+ }
+
+ iscsi_set_events(iscsilun);
+
+ return &acb->common;
+}
+
+static int64_t
+iscsi_getlength(BlockDriverState *bs)
+{
+ IscsiLun *iscsilun = bs->opaque;
+ int64_t len;
+
+ len = iscsilun->num_blocks;
+ len *= iscsilun->block_size;
+
+ return len;
+}
+
+static void
+iscsi_readcapacity10_cb(struct iscsi_context *iscsi, int status,
+ void *command_data, void *opaque)
+{
+ struct IscsiTask *itask = opaque;
+ struct scsi_readcapacity10 *rc10;
+ struct scsi_task *task = command_data;
+
+ if (status != 0) {
+ error_report("iSCSI: Failed to read capacity of iSCSI lun. %s",
+ iscsi_get_error(iscsi));
+ itask->status = 1;
+ itask->complete = 1;
+ scsi_free_scsi_task(task);
+ return;
+ }
+
+ rc10 = scsi_datain_unmarshall(task);
+ if (rc10 == NULL) {
+ error_report("iSCSI: Failed to unmarshall readcapacity10 data.");
+ itask->status = 1;
+ itask->complete = 1;
+ scsi_free_scsi_task(task);
+ return;
+ }
+
+ itask->iscsilun->block_size = rc10->block_size;
+ itask->iscsilun->num_blocks = rc10->lba;
+ itask->bs->total_sectors = (uint64_t)rc10->lba *
+ rc10->block_size / BDRV_SECTOR_SIZE ;
+
+ itask->status = 0;
+ itask->complete = 1;
+ scsi_free_scsi_task(task);
+}
+
+
+static void
+iscsi_connect_cb(struct iscsi_context *iscsi, int status, void *command_data,
+ void *opaque)
+{
+ struct IscsiTask *itask = opaque;
+ struct scsi_task *task;
+
+ if (status != 0) {
+ itask->status = 1;
+ itask->complete = 1;
+ return;
+ }
+
+ task = iscsi_readcapacity10_task(iscsi, itask->iscsilun->lun, 0, 0,
+ iscsi_readcapacity10_cb, opaque);
+ if (task == NULL) {
+ error_report("iSCSI: failed to send readcapacity command.");
+ itask->status = 1;
+ itask->complete = 1;
+ return;
+ }
+}
+
+/*
+ * We support iscsi url's on the form
+ * iscsi://[<username>%<password>@]<host>[:<port>]/<targetname>/<lun>
+ */
+static int iscsi_open(BlockDriverState *bs, const char *filename, int flags)
+{
+ IscsiLun *iscsilun = bs->opaque;
+ struct iscsi_context *iscsi = NULL;
+ struct iscsi_url *iscsi_url = NULL;
+ struct IscsiTask task;
+ int ret;
+
+ if ((BDRV_SECTOR_SIZE % 512) != 0) {
+ error_report("iSCSI: Invalid BDRV_SECTOR_SIZE. "
+ "BDRV_SECTOR_SIZE(%lld) is not a multiple "
+ "of 512", BDRV_SECTOR_SIZE);
+ return -EINVAL;
+ }
+
+ memset(iscsilun, 0, sizeof(IscsiLun));
+
+ /* Should really append the KVM name after the ':' here */
+ iscsi = iscsi_create_context("iqn.2008-11.org.linux-kvm:");
+ if (iscsi == NULL) {
+ error_report("iSCSI: Failed to create iSCSI context.");
+ ret = -ENOMEM;
+ goto failed;
+ }
+
+ iscsi_url = iscsi_parse_full_url(iscsi, filename);
+ if (iscsi_url == NULL) {
+ error_report("Failed to parse URL : %s %s", filename,
+ iscsi_get_error(iscsi));
+ ret = -EINVAL;
+ goto failed;
+ }
+
+ if (iscsi_set_targetname(iscsi, iscsi_url->target)) {
+ error_report("iSCSI: Failed to set target name.");
+ ret = -EINVAL;
+ goto failed;
+ }
+
+ if (iscsi_url->user != NULL) {
+ ret = iscsi_set_initiator_username_pwd(iscsi, iscsi_url->user,
+ iscsi_url->passwd);
+ if (ret != 0) {
+ error_report("Failed to set initiator username and password");
+ ret = -EINVAL;
+ goto failed;
+ }
+ }
+ if (iscsi_set_session_type(iscsi, ISCSI_SESSION_NORMAL) != 0) {
+ error_report("iSCSI: Failed to set session type to normal.");
+ ret = -EINVAL;
+ goto failed;
+ }
+
+ iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
+
+ task.iscsilun = iscsilun;
+ task.status = 0;
+ task.complete = 0;
+ task.bs = bs;
+
+ iscsilun->iscsi = iscsi;
+ iscsilun->lun = iscsi_url->lun;
+
+ if (iscsi_full_connect_async(iscsi, iscsi_url->portal, iscsi_url->lun,
+ iscsi_connect_cb, &task)
+ != 0) {
+ error_report("iSCSI: Failed to start async connect.");
+ ret = -EINVAL;
+ goto failed;
+ }
+
+ while (!task.complete) {
+ iscsi_set_events(iscsilun);
+ qemu_aio_wait();
+ }
+ if (task.status != 0) {
+ error_report("iSCSI: Failed to connect to LUN : %s",
+ iscsi_get_error(iscsi));
+ ret = -EINVAL;
+ goto failed;
+ }
+
+ if (iscsi_url != NULL) {
+ iscsi_destroy_url(iscsi_url);
+ }
+ return 0;
+
+failed:
+ if (iscsi_url != NULL) {
+ iscsi_destroy_url(iscsi_url);
+ }
+ if (iscsi != NULL) {
+ iscsi_destroy_context(iscsi);
+ }
+ memset(iscsilun, 0, sizeof(IscsiLun));
+ return ret;
+}
+
+static void iscsi_close(BlockDriverState *bs)
+{
+ IscsiLun *iscsilun = bs->opaque;
+ struct iscsi_context *iscsi = iscsilun->iscsi;
+
+ qemu_aio_set_fd_handler(iscsi_get_fd(iscsi), NULL, NULL, NULL, NULL, NULL);
+ iscsi_destroy_context(iscsi);
+ memset(iscsilun, 0, sizeof(IscsiLun));
+}
+
+static BlockDriver bdrv_iscsi = {
+ .format_name = "iscsi",
+ .protocol_name = "iscsi",
+
+ .instance_size = sizeof(IscsiLun),
+ .bdrv_file_open = iscsi_open,
+ .bdrv_close = iscsi_close,
+
+ .bdrv_getlength = iscsi_getlength,
+
+ .bdrv_aio_readv = iscsi_aio_readv,
+ .bdrv_aio_writev = iscsi_aio_writev,
+ .bdrv_aio_flush = iscsi_aio_flush,
+};
+
+static void iscsi_block_init(void)
+{
+ bdrv_register(&bdrv_iscsi);
+}
+
+block_init(iscsi_block_init);
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-23 16:19:40 +0000