xref: /openbmc/qemu/block/iscsi.c (revision 35a6ed4f)
1 /*
2  * QEMU Block driver for iSCSI images
3  *
4  * Copyright (c) 2010-2011 Ronnie Sahlberg <ronniesahlberg@gmail.com>
5  * Copyright (c) 2012-2016 Peter Lieven <pl@kamp.de>
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 
26 #include "qemu/osdep.h"
27 
28 #include <poll.h>
29 #include <math.h>
30 #include <arpa/inet.h>
31 #include "qemu-common.h"
32 #include "qemu/config-file.h"
33 #include "qemu/error-report.h"
34 #include "qemu/bitops.h"
35 #include "qemu/bitmap.h"
36 #include "block/block_int.h"
37 #include "block/scsi.h"
38 #include "qemu/iov.h"
39 #include "qemu/uuid.h"
40 #include "qmp-commands.h"
41 #include "qapi/qmp/qstring.h"
42 #include "crypto/secret.h"
43 
44 #include <iscsi/iscsi.h>
45 #include <iscsi/scsi-lowlevel.h>
46 
47 #ifdef __linux__
48 #include <scsi/sg.h>
49 #endif
50 
51 typedef struct IscsiLun {
52     struct iscsi_context *iscsi;
53     AioContext *aio_context;
54     int lun;
55     enum scsi_inquiry_peripheral_device_type type;
56     int block_size;
57     uint64_t num_blocks;
58     int events;
59     QEMUTimer *nop_timer;
60     QEMUTimer *event_timer;
61     struct scsi_inquiry_logical_block_provisioning lbp;
62     struct scsi_inquiry_block_limits bl;
63     unsigned char *zeroblock;
64     /* The allocmap tracks which clusters (pages) on the iSCSI target are
65      * allocated and which are not. In case a target returns zeros for
66      * unallocated pages (iscsilun->lprz) we can directly return zeros instead
67      * of reading zeros over the wire if a read request falls within an
68      * unallocated block. As there are 3 possible states we need 2 bitmaps to
69      * track. allocmap_valid keeps track if QEMU's information about a page is
70      * valid. allocmap tracks if a page is allocated or not. In case QEMU has no
71      * valid information about a page the corresponding allocmap entry should be
72      * switched to unallocated as well to force a new lookup of the allocation
73      * status as lookups are generally skipped if a page is suspect to be
74      * allocated. If a iSCSI target is opened with cache.direct = on the
75      * allocmap_valid does not exist turning all cached information invalid so
76      * that a fresh lookup is made for any page even if allocmap entry returns
77      * it's unallocated. */
78     unsigned long *allocmap;
79     unsigned long *allocmap_valid;
80     long allocmap_size;
81     int cluster_sectors;
82     bool use_16_for_rw;
83     bool write_protected;
84     bool lbpme;
85     bool lbprz;
86     bool dpofua;
87     bool has_write_same;
88     bool request_timed_out;
89 } IscsiLun;
90 
91 typedef struct IscsiTask {
92     int status;
93     int complete;
94     int retries;
95     int do_retry;
96     struct scsi_task *task;
97     Coroutine *co;
98     IscsiLun *iscsilun;
99     QEMUTimer retry_timer;
100     int err_code;
101 } IscsiTask;
102 
103 typedef struct IscsiAIOCB {
104     BlockAIOCB common;
105     QEMUIOVector *qiov;
106     QEMUBH *bh;
107     IscsiLun *iscsilun;
108     struct scsi_task *task;
109     uint8_t *buf;
110     int status;
111     int64_t sector_num;
112     int nb_sectors;
113     int ret;
114 #ifdef __linux__
115     sg_io_hdr_t *ioh;
116 #endif
117 } IscsiAIOCB;
118 
119 /* libiscsi uses time_t so its enough to process events every second */
120 #define EVENT_INTERVAL 1000
121 #define NOP_INTERVAL 5000
122 #define MAX_NOP_FAILURES 3
123 #define ISCSI_CMD_RETRIES ARRAY_SIZE(iscsi_retry_times)
124 static const unsigned iscsi_retry_times[] = {8, 32, 128, 512, 2048, 8192, 32768};
125 
126 /* this threshold is a trade-off knob to choose between
127  * the potential additional overhead of an extra GET_LBA_STATUS request
128  * vs. unnecessarily reading a lot of zero sectors over the wire.
129  * If a read request is greater or equal than ISCSI_CHECKALLOC_THRES
130  * sectors we check the allocation status of the area covered by the
131  * request first if the allocationmap indicates that the area might be
132  * unallocated. */
133 #define ISCSI_CHECKALLOC_THRES 64
134 
135 static void
136 iscsi_bh_cb(void *p)
137 {
138     IscsiAIOCB *acb = p;
139 
140     qemu_bh_delete(acb->bh);
141 
142     g_free(acb->buf);
143     acb->buf = NULL;
144 
145     acb->common.cb(acb->common.opaque, acb->status);
146 
147     if (acb->task != NULL) {
148         scsi_free_scsi_task(acb->task);
149         acb->task = NULL;
150     }
151 
152     qemu_aio_unref(acb);
153 }
154 
155 static void
156 iscsi_schedule_bh(IscsiAIOCB *acb)
157 {
158     if (acb->bh) {
159         return;
160     }
161     acb->bh = aio_bh_new(acb->iscsilun->aio_context, iscsi_bh_cb, acb);
162     qemu_bh_schedule(acb->bh);
163 }
164 
165 static void iscsi_co_generic_bh_cb(void *opaque)
166 {
167     struct IscsiTask *iTask = opaque;
168     iTask->complete = 1;
169     qemu_coroutine_enter(iTask->co);
170 }
171 
172 static void iscsi_retry_timer_expired(void *opaque)
173 {
174     struct IscsiTask *iTask = opaque;
175     iTask->complete = 1;
176     if (iTask->co) {
177         qemu_coroutine_enter(iTask->co);
178     }
179 }
180 
181 static inline unsigned exp_random(double mean)
182 {
183     return -mean * log((double)rand() / RAND_MAX);
184 }
185 
186 /* SCSI_SENSE_ASCQ_INVALID_FIELD_IN_PARAMETER_LIST was introduced in
187  * libiscsi 1.10.0, together with other constants we need.  Use it as
188  * a hint that we have to define them ourselves if needed, to keep the
189  * minimum required libiscsi version at 1.9.0.  We use an ASCQ macro for
190  * the test because SCSI_STATUS_* is an enum.
191  *
192  * To guard against future changes where SCSI_SENSE_ASCQ_* also becomes
193  * an enum, check against the LIBISCSI_API_VERSION macro, which was
194  * introduced in 1.11.0.  If it is present, there is no need to define
195  * anything.
196  */
197 #if !defined(SCSI_SENSE_ASCQ_INVALID_FIELD_IN_PARAMETER_LIST) && \
198     !defined(LIBISCSI_API_VERSION)
199 #define SCSI_STATUS_TASK_SET_FULL                          0x28
200 #define SCSI_STATUS_TIMEOUT                                0x0f000002
201 #define SCSI_SENSE_ASCQ_INVALID_FIELD_IN_PARAMETER_LIST    0x2600
202 #define SCSI_SENSE_ASCQ_PARAMETER_LIST_LENGTH_ERROR        0x1a00
203 #endif
204 
205 #ifndef LIBISCSI_API_VERSION
206 #define LIBISCSI_API_VERSION 20130701
207 #endif
208 
209 static int iscsi_translate_sense(struct scsi_sense *sense)
210 {
211     int ret;
212 
213     switch (sense->key) {
214     case SCSI_SENSE_NOT_READY:
215         return -EBUSY;
216     case SCSI_SENSE_DATA_PROTECTION:
217         return -EACCES;
218     case SCSI_SENSE_COMMAND_ABORTED:
219         return -ECANCELED;
220     case SCSI_SENSE_ILLEGAL_REQUEST:
221         /* Parse ASCQ */
222         break;
223     default:
224         return -EIO;
225     }
226     switch (sense->ascq) {
227     case SCSI_SENSE_ASCQ_PARAMETER_LIST_LENGTH_ERROR:
228     case SCSI_SENSE_ASCQ_INVALID_OPERATION_CODE:
229     case SCSI_SENSE_ASCQ_INVALID_FIELD_IN_CDB:
230     case SCSI_SENSE_ASCQ_INVALID_FIELD_IN_PARAMETER_LIST:
231         ret = -EINVAL;
232         break;
233     case SCSI_SENSE_ASCQ_LBA_OUT_OF_RANGE:
234         ret = -ENOSPC;
235         break;
236     case SCSI_SENSE_ASCQ_LOGICAL_UNIT_NOT_SUPPORTED:
237         ret = -ENOTSUP;
238         break;
239     case SCSI_SENSE_ASCQ_MEDIUM_NOT_PRESENT:
240     case SCSI_SENSE_ASCQ_MEDIUM_NOT_PRESENT_TRAY_CLOSED:
241     case SCSI_SENSE_ASCQ_MEDIUM_NOT_PRESENT_TRAY_OPEN:
242         ret = -ENOMEDIUM;
243         break;
244     case SCSI_SENSE_ASCQ_WRITE_PROTECTED:
245         ret = -EACCES;
246         break;
247     default:
248         ret = -EIO;
249         break;
250     }
251     return ret;
252 }
253 
254 static void
255 iscsi_co_generic_cb(struct iscsi_context *iscsi, int status,
256                         void *command_data, void *opaque)
257 {
258     struct IscsiTask *iTask = opaque;
259     struct scsi_task *task = command_data;
260 
261     iTask->status = status;
262     iTask->do_retry = 0;
263     iTask->task = task;
264 
265     if (status != SCSI_STATUS_GOOD) {
266         if (iTask->retries++ < ISCSI_CMD_RETRIES) {
267             if (status == SCSI_STATUS_CHECK_CONDITION
268                 && task->sense.key == SCSI_SENSE_UNIT_ATTENTION) {
269                 error_report("iSCSI CheckCondition: %s",
270                              iscsi_get_error(iscsi));
271                 iTask->do_retry = 1;
272                 goto out;
273             }
274             if (status == SCSI_STATUS_BUSY ||
275                 status == SCSI_STATUS_TIMEOUT ||
276                 status == SCSI_STATUS_TASK_SET_FULL) {
277                 unsigned retry_time =
278                     exp_random(iscsi_retry_times[iTask->retries - 1]);
279                 if (status == SCSI_STATUS_TIMEOUT) {
280                     /* make sure the request is rescheduled AFTER the
281                      * reconnect is initiated */
282                     retry_time = EVENT_INTERVAL * 2;
283                     iTask->iscsilun->request_timed_out = true;
284                 }
285                 error_report("iSCSI Busy/TaskSetFull/TimeOut"
286                              " (retry #%u in %u ms): %s",
287                              iTask->retries, retry_time,
288                              iscsi_get_error(iscsi));
289                 aio_timer_init(iTask->iscsilun->aio_context,
290                                &iTask->retry_timer, QEMU_CLOCK_REALTIME,
291                                SCALE_MS, iscsi_retry_timer_expired, iTask);
292                 timer_mod(&iTask->retry_timer,
293                           qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + retry_time);
294                 iTask->do_retry = 1;
295                 return;
296             }
297         }
298         iTask->err_code = iscsi_translate_sense(&task->sense);
299         error_report("iSCSI Failure: %s", iscsi_get_error(iscsi));
300     }
301 
302 out:
303     if (iTask->co) {
304         aio_bh_schedule_oneshot(iTask->iscsilun->aio_context,
305                                  iscsi_co_generic_bh_cb, iTask);
306     } else {
307         iTask->complete = 1;
308     }
309 }
310 
311 static void iscsi_co_init_iscsitask(IscsiLun *iscsilun, struct IscsiTask *iTask)
312 {
313     *iTask = (struct IscsiTask) {
314         .co         = qemu_coroutine_self(),
315         .iscsilun   = iscsilun,
316     };
317 }
318 
319 static void
320 iscsi_abort_task_cb(struct iscsi_context *iscsi, int status, void *command_data,
321                     void *private_data)
322 {
323     IscsiAIOCB *acb = private_data;
324 
325     acb->status = -ECANCELED;
326     iscsi_schedule_bh(acb);
327 }
328 
329 static void
330 iscsi_aio_cancel(BlockAIOCB *blockacb)
331 {
332     IscsiAIOCB *acb = (IscsiAIOCB *)blockacb;
333     IscsiLun *iscsilun = acb->iscsilun;
334 
335     if (acb->status != -EINPROGRESS) {
336         return;
337     }
338 
339     /* send a task mgmt call to the target to cancel the task on the target */
340     iscsi_task_mgmt_abort_task_async(iscsilun->iscsi, acb->task,
341                                      iscsi_abort_task_cb, acb);
342 
343 }
344 
345 static const AIOCBInfo iscsi_aiocb_info = {
346     .aiocb_size         = sizeof(IscsiAIOCB),
347     .cancel_async       = iscsi_aio_cancel,
348 };
349 
350 
351 static void iscsi_process_read(void *arg);
352 static void iscsi_process_write(void *arg);
353 
354 static void
355 iscsi_set_events(IscsiLun *iscsilun)
356 {
357     struct iscsi_context *iscsi = iscsilun->iscsi;
358     int ev = iscsi_which_events(iscsi);
359 
360     if (ev != iscsilun->events) {
361         aio_set_fd_handler(iscsilun->aio_context, iscsi_get_fd(iscsi),
362                            false,
363                            (ev & POLLIN) ? iscsi_process_read : NULL,
364                            (ev & POLLOUT) ? iscsi_process_write : NULL,
365                            iscsilun);
366         iscsilun->events = ev;
367     }
368 }
369 
370 static void iscsi_timed_check_events(void *opaque)
371 {
372     IscsiLun *iscsilun = opaque;
373 
374     /* check for timed out requests */
375     iscsi_service(iscsilun->iscsi, 0);
376 
377     if (iscsilun->request_timed_out) {
378         iscsilun->request_timed_out = false;
379         iscsi_reconnect(iscsilun->iscsi);
380     }
381 
382     /* newer versions of libiscsi may return zero events. Ensure we are able
383      * to return to service once this situation changes. */
384     iscsi_set_events(iscsilun);
385 
386     timer_mod(iscsilun->event_timer,
387               qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + EVENT_INTERVAL);
388 }
389 
390 static void
391 iscsi_process_read(void *arg)
392 {
393     IscsiLun *iscsilun = arg;
394     struct iscsi_context *iscsi = iscsilun->iscsi;
395 
396     iscsi_service(iscsi, POLLIN);
397     iscsi_set_events(iscsilun);
398 }
399 
400 static void
401 iscsi_process_write(void *arg)
402 {
403     IscsiLun *iscsilun = arg;
404     struct iscsi_context *iscsi = iscsilun->iscsi;
405 
406     iscsi_service(iscsi, POLLOUT);
407     iscsi_set_events(iscsilun);
408 }
409 
410 static int64_t sector_lun2qemu(int64_t sector, IscsiLun *iscsilun)
411 {
412     return sector * iscsilun->block_size / BDRV_SECTOR_SIZE;
413 }
414 
415 static int64_t sector_qemu2lun(int64_t sector, IscsiLun *iscsilun)
416 {
417     return sector * BDRV_SECTOR_SIZE / iscsilun->block_size;
418 }
419 
420 static bool is_byte_request_lun_aligned(int64_t offset, int count,
421                                         IscsiLun *iscsilun)
422 {
423     if (offset % iscsilun->block_size || count % iscsilun->block_size) {
424         error_report("iSCSI misaligned request: "
425                      "iscsilun->block_size %u, offset %" PRIi64
426                      ", count %d",
427                      iscsilun->block_size, offset, count);
428         return false;
429     }
430     return true;
431 }
432 
433 static bool is_sector_request_lun_aligned(int64_t sector_num, int nb_sectors,
434                                           IscsiLun *iscsilun)
435 {
436     assert(nb_sectors <= BDRV_REQUEST_MAX_SECTORS);
437     return is_byte_request_lun_aligned(sector_num << BDRV_SECTOR_BITS,
438                                        nb_sectors << BDRV_SECTOR_BITS,
439                                        iscsilun);
440 }
441 
442 static void iscsi_allocmap_free(IscsiLun *iscsilun)
443 {
444     g_free(iscsilun->allocmap);
445     g_free(iscsilun->allocmap_valid);
446     iscsilun->allocmap = NULL;
447     iscsilun->allocmap_valid = NULL;
448 }
449 
450 
451 static int iscsi_allocmap_init(IscsiLun *iscsilun, int open_flags)
452 {
453     iscsi_allocmap_free(iscsilun);
454 
455     iscsilun->allocmap_size =
456         DIV_ROUND_UP(sector_lun2qemu(iscsilun->num_blocks, iscsilun),
457                      iscsilun->cluster_sectors);
458 
459     iscsilun->allocmap = bitmap_try_new(iscsilun->allocmap_size);
460     if (!iscsilun->allocmap) {
461         return -ENOMEM;
462     }
463 
464     if (open_flags & BDRV_O_NOCACHE) {
465         /* in case that cache.direct = on all allocmap entries are
466          * treated as invalid to force a relookup of the block
467          * status on every read request */
468         return 0;
469     }
470 
471     iscsilun->allocmap_valid = bitmap_try_new(iscsilun->allocmap_size);
472     if (!iscsilun->allocmap_valid) {
473         /* if we are under memory pressure free the allocmap as well */
474         iscsi_allocmap_free(iscsilun);
475         return -ENOMEM;
476     }
477 
478     return 0;
479 }
480 
481 static void
482 iscsi_allocmap_update(IscsiLun *iscsilun, int64_t sector_num,
483                       int nb_sectors, bool allocated, bool valid)
484 {
485     int64_t cl_num_expanded, nb_cls_expanded, cl_num_shrunk, nb_cls_shrunk;
486 
487     if (iscsilun->allocmap == NULL) {
488         return;
489     }
490     /* expand to entirely contain all affected clusters */
491     cl_num_expanded = sector_num / iscsilun->cluster_sectors;
492     nb_cls_expanded = DIV_ROUND_UP(sector_num + nb_sectors,
493                                    iscsilun->cluster_sectors) - cl_num_expanded;
494     /* shrink to touch only completely contained clusters */
495     cl_num_shrunk = DIV_ROUND_UP(sector_num, iscsilun->cluster_sectors);
496     nb_cls_shrunk = (sector_num + nb_sectors) / iscsilun->cluster_sectors
497                       - cl_num_shrunk;
498     if (allocated) {
499         bitmap_set(iscsilun->allocmap, cl_num_expanded, nb_cls_expanded);
500     } else {
501         bitmap_clear(iscsilun->allocmap, cl_num_shrunk, nb_cls_shrunk);
502     }
503 
504     if (iscsilun->allocmap_valid == NULL) {
505         return;
506     }
507     if (valid) {
508         bitmap_set(iscsilun->allocmap_valid, cl_num_shrunk, nb_cls_shrunk);
509     } else {
510         bitmap_clear(iscsilun->allocmap_valid, cl_num_expanded,
511                      nb_cls_expanded);
512     }
513 }
514 
515 static void
516 iscsi_allocmap_set_allocated(IscsiLun *iscsilun, int64_t sector_num,
517                              int nb_sectors)
518 {
519     iscsi_allocmap_update(iscsilun, sector_num, nb_sectors, true, true);
520 }
521 
522 static void
523 iscsi_allocmap_set_unallocated(IscsiLun *iscsilun, int64_t sector_num,
524                                int nb_sectors)
525 {
526     /* Note: if cache.direct=on the fifth argument to iscsi_allocmap_update
527      * is ignored, so this will in effect be an iscsi_allocmap_set_invalid.
528      */
529     iscsi_allocmap_update(iscsilun, sector_num, nb_sectors, false, true);
530 }
531 
532 static void iscsi_allocmap_set_invalid(IscsiLun *iscsilun, int64_t sector_num,
533                                        int nb_sectors)
534 {
535     iscsi_allocmap_update(iscsilun, sector_num, nb_sectors, false, false);
536 }
537 
538 static void iscsi_allocmap_invalidate(IscsiLun *iscsilun)
539 {
540     if (iscsilun->allocmap) {
541         bitmap_zero(iscsilun->allocmap, iscsilun->allocmap_size);
542     }
543     if (iscsilun->allocmap_valid) {
544         bitmap_zero(iscsilun->allocmap_valid, iscsilun->allocmap_size);
545     }
546 }
547 
548 static inline bool
549 iscsi_allocmap_is_allocated(IscsiLun *iscsilun, int64_t sector_num,
550                             int nb_sectors)
551 {
552     unsigned long size;
553     if (iscsilun->allocmap == NULL) {
554         return true;
555     }
556     size = DIV_ROUND_UP(sector_num + nb_sectors, iscsilun->cluster_sectors);
557     return !(find_next_bit(iscsilun->allocmap, size,
558                            sector_num / iscsilun->cluster_sectors) == size);
559 }
560 
561 static inline bool iscsi_allocmap_is_valid(IscsiLun *iscsilun,
562                                            int64_t sector_num, int nb_sectors)
563 {
564     unsigned long size;
565     if (iscsilun->allocmap_valid == NULL) {
566         return false;
567     }
568     size = DIV_ROUND_UP(sector_num + nb_sectors, iscsilun->cluster_sectors);
569     return (find_next_zero_bit(iscsilun->allocmap_valid, size,
570                                sector_num / iscsilun->cluster_sectors) == size);
571 }
572 
573 static int coroutine_fn
574 iscsi_co_writev_flags(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
575                       QEMUIOVector *iov, int flags)
576 {
577     IscsiLun *iscsilun = bs->opaque;
578     struct IscsiTask iTask;
579     uint64_t lba;
580     uint32_t num_sectors;
581     bool fua = flags & BDRV_REQ_FUA;
582 
583     if (fua) {
584         assert(iscsilun->dpofua);
585     }
586     if (!is_sector_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
587         return -EINVAL;
588     }
589 
590     if (bs->bl.max_transfer) {
591         assert(nb_sectors << BDRV_SECTOR_BITS <= bs->bl.max_transfer);
592     }
593 
594     lba = sector_qemu2lun(sector_num, iscsilun);
595     num_sectors = sector_qemu2lun(nb_sectors, iscsilun);
596     iscsi_co_init_iscsitask(iscsilun, &iTask);
597 retry:
598     if (iscsilun->use_16_for_rw) {
599 #if LIBISCSI_API_VERSION >= (20160603)
600         iTask.task = iscsi_write16_iov_task(iscsilun->iscsi, iscsilun->lun, lba,
601                                             NULL, num_sectors * iscsilun->block_size,
602                                             iscsilun->block_size, 0, 0, fua, 0, 0,
603                                             iscsi_co_generic_cb, &iTask,
604                                             (struct scsi_iovec *)iov->iov, iov->niov);
605     } else {
606         iTask.task = iscsi_write10_iov_task(iscsilun->iscsi, iscsilun->lun, lba,
607                                             NULL, num_sectors * iscsilun->block_size,
608                                             iscsilun->block_size, 0, 0, fua, 0, 0,
609                                             iscsi_co_generic_cb, &iTask,
610                                             (struct scsi_iovec *)iov->iov, iov->niov);
611     }
612 #else
613         iTask.task = iscsi_write16_task(iscsilun->iscsi, iscsilun->lun, lba,
614                                         NULL, num_sectors * iscsilun->block_size,
615                                         iscsilun->block_size, 0, 0, fua, 0, 0,
616                                         iscsi_co_generic_cb, &iTask);
617     } else {
618         iTask.task = iscsi_write10_task(iscsilun->iscsi, iscsilun->lun, lba,
619                                         NULL, num_sectors * iscsilun->block_size,
620                                         iscsilun->block_size, 0, 0, fua, 0, 0,
621                                         iscsi_co_generic_cb, &iTask);
622     }
623 #endif
624     if (iTask.task == NULL) {
625         return -ENOMEM;
626     }
627 #if LIBISCSI_API_VERSION < (20160603)
628     scsi_task_set_iov_out(iTask.task, (struct scsi_iovec *) iov->iov,
629                           iov->niov);
630 #endif
631     while (!iTask.complete) {
632         iscsi_set_events(iscsilun);
633         qemu_coroutine_yield();
634     }
635 
636     if (iTask.task != NULL) {
637         scsi_free_scsi_task(iTask.task);
638         iTask.task = NULL;
639     }
640 
641     if (iTask.do_retry) {
642         iTask.complete = 0;
643         goto retry;
644     }
645 
646     if (iTask.status != SCSI_STATUS_GOOD) {
647         iscsi_allocmap_set_invalid(iscsilun, sector_num, nb_sectors);
648         return iTask.err_code;
649     }
650 
651     iscsi_allocmap_set_allocated(iscsilun, sector_num, nb_sectors);
652 
653     return 0;
654 }
655 
656 
657 
658 static int64_t coroutine_fn iscsi_co_get_block_status(BlockDriverState *bs,
659                                                   int64_t sector_num,
660                                                   int nb_sectors, int *pnum,
661                                                   BlockDriverState **file)
662 {
663     IscsiLun *iscsilun = bs->opaque;
664     struct scsi_get_lba_status *lbas = NULL;
665     struct scsi_lba_status_descriptor *lbasd = NULL;
666     struct IscsiTask iTask;
667     int64_t ret;
668 
669     iscsi_co_init_iscsitask(iscsilun, &iTask);
670 
671     if (!is_sector_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
672         ret = -EINVAL;
673         goto out;
674     }
675 
676     /* default to all sectors allocated */
677     ret = BDRV_BLOCK_DATA;
678     ret |= (sector_num << BDRV_SECTOR_BITS) | BDRV_BLOCK_OFFSET_VALID;
679     *pnum = nb_sectors;
680 
681     /* LUN does not support logical block provisioning */
682     if (!iscsilun->lbpme) {
683         goto out;
684     }
685 
686 retry:
687     if (iscsi_get_lba_status_task(iscsilun->iscsi, iscsilun->lun,
688                                   sector_qemu2lun(sector_num, iscsilun),
689                                   8 + 16, iscsi_co_generic_cb,
690                                   &iTask) == NULL) {
691         ret = -ENOMEM;
692         goto out;
693     }
694 
695     while (!iTask.complete) {
696         iscsi_set_events(iscsilun);
697         qemu_coroutine_yield();
698     }
699 
700     if (iTask.do_retry) {
701         if (iTask.task != NULL) {
702             scsi_free_scsi_task(iTask.task);
703             iTask.task = NULL;
704         }
705         iTask.complete = 0;
706         goto retry;
707     }
708 
709     if (iTask.status != SCSI_STATUS_GOOD) {
710         /* in case the get_lba_status_callout fails (i.e.
711          * because the device is busy or the cmd is not
712          * supported) we pretend all blocks are allocated
713          * for backwards compatibility */
714         goto out;
715     }
716 
717     lbas = scsi_datain_unmarshall(iTask.task);
718     if (lbas == NULL) {
719         ret = -EIO;
720         goto out;
721     }
722 
723     lbasd = &lbas->descriptors[0];
724 
725     if (sector_qemu2lun(sector_num, iscsilun) != lbasd->lba) {
726         ret = -EIO;
727         goto out;
728     }
729 
730     *pnum = sector_lun2qemu(lbasd->num_blocks, iscsilun);
731 
732     if (lbasd->provisioning == SCSI_PROVISIONING_TYPE_DEALLOCATED ||
733         lbasd->provisioning == SCSI_PROVISIONING_TYPE_ANCHORED) {
734         ret &= ~BDRV_BLOCK_DATA;
735         if (iscsilun->lbprz) {
736             ret |= BDRV_BLOCK_ZERO;
737         }
738     }
739 
740     if (ret & BDRV_BLOCK_ZERO) {
741         iscsi_allocmap_set_unallocated(iscsilun, sector_num, *pnum);
742     } else {
743         iscsi_allocmap_set_allocated(iscsilun, sector_num, *pnum);
744     }
745 
746     if (*pnum > nb_sectors) {
747         *pnum = nb_sectors;
748     }
749 out:
750     if (iTask.task != NULL) {
751         scsi_free_scsi_task(iTask.task);
752     }
753     if (ret > 0 && ret & BDRV_BLOCK_OFFSET_VALID) {
754         *file = bs;
755     }
756     return ret;
757 }
758 
759 static int coroutine_fn iscsi_co_readv(BlockDriverState *bs,
760                                        int64_t sector_num, int nb_sectors,
761                                        QEMUIOVector *iov)
762 {
763     IscsiLun *iscsilun = bs->opaque;
764     struct IscsiTask iTask;
765     uint64_t lba;
766     uint32_t num_sectors;
767 
768     if (!is_sector_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
769         return -EINVAL;
770     }
771 
772     if (bs->bl.max_transfer) {
773         assert(nb_sectors << BDRV_SECTOR_BITS <= bs->bl.max_transfer);
774     }
775 
776     /* if cache.direct is off and we have a valid entry in our allocation map
777      * we can skip checking the block status and directly return zeroes if
778      * the request falls within an unallocated area */
779     if (iscsi_allocmap_is_valid(iscsilun, sector_num, nb_sectors) &&
780         !iscsi_allocmap_is_allocated(iscsilun, sector_num, nb_sectors)) {
781             qemu_iovec_memset(iov, 0, 0x00, iov->size);
782             return 0;
783     }
784 
785     if (nb_sectors >= ISCSI_CHECKALLOC_THRES &&
786         !iscsi_allocmap_is_valid(iscsilun, sector_num, nb_sectors) &&
787         !iscsi_allocmap_is_allocated(iscsilun, sector_num, nb_sectors)) {
788         int pnum;
789         BlockDriverState *file;
790         /* check the block status from the beginning of the cluster
791          * containing the start sector */
792         int64_t ret = iscsi_co_get_block_status(bs,
793                           sector_num - sector_num % iscsilun->cluster_sectors,
794                           BDRV_REQUEST_MAX_SECTORS, &pnum, &file);
795         if (ret < 0) {
796             return ret;
797         }
798         /* if the whole request falls into an unallocated area we can avoid
799          * to read and directly return zeroes instead */
800         if (ret & BDRV_BLOCK_ZERO &&
801             pnum >= nb_sectors + sector_num % iscsilun->cluster_sectors) {
802             qemu_iovec_memset(iov, 0, 0x00, iov->size);
803             return 0;
804         }
805     }
806 
807     lba = sector_qemu2lun(sector_num, iscsilun);
808     num_sectors = sector_qemu2lun(nb_sectors, iscsilun);
809 
810     iscsi_co_init_iscsitask(iscsilun, &iTask);
811 retry:
812     if (iscsilun->use_16_for_rw) {
813 #if LIBISCSI_API_VERSION >= (20160603)
814         iTask.task = iscsi_read16_iov_task(iscsilun->iscsi, iscsilun->lun, lba,
815                                            num_sectors * iscsilun->block_size,
816                                            iscsilun->block_size, 0, 0, 0, 0, 0,
817                                            iscsi_co_generic_cb, &iTask,
818                                            (struct scsi_iovec *)iov->iov, iov->niov);
819     } else {
820         iTask.task = iscsi_read10_iov_task(iscsilun->iscsi, iscsilun->lun, lba,
821                                            num_sectors * iscsilun->block_size,
822                                            iscsilun->block_size,
823                                            0, 0, 0, 0, 0,
824                                            iscsi_co_generic_cb, &iTask,
825                                            (struct scsi_iovec *)iov->iov, iov->niov);
826     }
827 #else
828         iTask.task = iscsi_read16_task(iscsilun->iscsi, iscsilun->lun, lba,
829                                        num_sectors * iscsilun->block_size,
830                                        iscsilun->block_size, 0, 0, 0, 0, 0,
831                                        iscsi_co_generic_cb, &iTask);
832     } else {
833         iTask.task = iscsi_read10_task(iscsilun->iscsi, iscsilun->lun, lba,
834                                        num_sectors * iscsilun->block_size,
835                                        iscsilun->block_size,
836                                        0, 0, 0, 0, 0,
837                                        iscsi_co_generic_cb, &iTask);
838     }
839 #endif
840     if (iTask.task == NULL) {
841         return -ENOMEM;
842     }
843 #if LIBISCSI_API_VERSION < (20160603)
844     scsi_task_set_iov_in(iTask.task, (struct scsi_iovec *) iov->iov, iov->niov);
845 #endif
846     while (!iTask.complete) {
847         iscsi_set_events(iscsilun);
848         qemu_coroutine_yield();
849     }
850 
851     if (iTask.task != NULL) {
852         scsi_free_scsi_task(iTask.task);
853         iTask.task = NULL;
854     }
855 
856     if (iTask.do_retry) {
857         iTask.complete = 0;
858         goto retry;
859     }
860 
861     if (iTask.status != SCSI_STATUS_GOOD) {
862         return iTask.err_code;
863     }
864 
865     return 0;
866 }
867 
868 static int coroutine_fn iscsi_co_flush(BlockDriverState *bs)
869 {
870     IscsiLun *iscsilun = bs->opaque;
871     struct IscsiTask iTask;
872 
873     iscsi_co_init_iscsitask(iscsilun, &iTask);
874 retry:
875     if (iscsi_synchronizecache10_task(iscsilun->iscsi, iscsilun->lun, 0, 0, 0,
876                                       0, iscsi_co_generic_cb, &iTask) == NULL) {
877         return -ENOMEM;
878     }
879 
880     while (!iTask.complete) {
881         iscsi_set_events(iscsilun);
882         qemu_coroutine_yield();
883     }
884 
885     if (iTask.task != NULL) {
886         scsi_free_scsi_task(iTask.task);
887         iTask.task = NULL;
888     }
889 
890     if (iTask.do_retry) {
891         iTask.complete = 0;
892         goto retry;
893     }
894 
895     if (iTask.status != SCSI_STATUS_GOOD) {
896         return iTask.err_code;
897     }
898 
899     return 0;
900 }
901 
902 #ifdef __linux__
903 static void
904 iscsi_aio_ioctl_cb(struct iscsi_context *iscsi, int status,
905                      void *command_data, void *opaque)
906 {
907     IscsiAIOCB *acb = opaque;
908 
909     g_free(acb->buf);
910     acb->buf = NULL;
911 
912     acb->status = 0;
913     if (status < 0) {
914         error_report("Failed to ioctl(SG_IO) to iSCSI lun. %s",
915                      iscsi_get_error(iscsi));
916         acb->status = iscsi_translate_sense(&acb->task->sense);
917     }
918 
919     acb->ioh->driver_status = 0;
920     acb->ioh->host_status   = 0;
921     acb->ioh->resid         = 0;
922     acb->ioh->status        = status;
923 
924 #define SG_ERR_DRIVER_SENSE    0x08
925 
926     if (status == SCSI_STATUS_CHECK_CONDITION && acb->task->datain.size >= 2) {
927         int ss;
928 
929         acb->ioh->driver_status |= SG_ERR_DRIVER_SENSE;
930 
931         acb->ioh->sb_len_wr = acb->task->datain.size - 2;
932         ss = (acb->ioh->mx_sb_len >= acb->ioh->sb_len_wr) ?
933              acb->ioh->mx_sb_len : acb->ioh->sb_len_wr;
934         memcpy(acb->ioh->sbp, &acb->task->datain.data[2], ss);
935     }
936 
937     iscsi_schedule_bh(acb);
938 }
939 
940 static void iscsi_ioctl_bh_completion(void *opaque)
941 {
942     IscsiAIOCB *acb = opaque;
943 
944     qemu_bh_delete(acb->bh);
945     acb->common.cb(acb->common.opaque, acb->ret);
946     qemu_aio_unref(acb);
947 }
948 
949 static void iscsi_ioctl_handle_emulated(IscsiAIOCB *acb, int req, void *buf)
950 {
951     BlockDriverState *bs = acb->common.bs;
952     IscsiLun *iscsilun = bs->opaque;
953     int ret = 0;
954 
955     switch (req) {
956     case SG_GET_VERSION_NUM:
957         *(int *)buf = 30000;
958         break;
959     case SG_GET_SCSI_ID:
960         ((struct sg_scsi_id *)buf)->scsi_type = iscsilun->type;
961         break;
962     default:
963         ret = -EINVAL;
964     }
965     assert(!acb->bh);
966     acb->bh = aio_bh_new(bdrv_get_aio_context(bs),
967                          iscsi_ioctl_bh_completion, acb);
968     acb->ret = ret;
969     qemu_bh_schedule(acb->bh);
970 }
971 
972 static BlockAIOCB *iscsi_aio_ioctl(BlockDriverState *bs,
973         unsigned long int req, void *buf,
974         BlockCompletionFunc *cb, void *opaque)
975 {
976     IscsiLun *iscsilun = bs->opaque;
977     struct iscsi_context *iscsi = iscsilun->iscsi;
978     struct iscsi_data data;
979     IscsiAIOCB *acb;
980 
981     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
982 
983     acb->iscsilun = iscsilun;
984     acb->bh          = NULL;
985     acb->status      = -EINPROGRESS;
986     acb->buf         = NULL;
987     acb->ioh         = buf;
988 
989     if (req != SG_IO) {
990         iscsi_ioctl_handle_emulated(acb, req, buf);
991         return &acb->common;
992     }
993 
994     if (acb->ioh->cmd_len > SCSI_CDB_MAX_SIZE) {
995         error_report("iSCSI: ioctl error CDB exceeds max size (%d > %d)",
996                      acb->ioh->cmd_len, SCSI_CDB_MAX_SIZE);
997         qemu_aio_unref(acb);
998         return NULL;
999     }
1000 
1001     acb->task = malloc(sizeof(struct scsi_task));
1002     if (acb->task == NULL) {
1003         error_report("iSCSI: Failed to allocate task for scsi command. %s",
1004                      iscsi_get_error(iscsi));
1005         qemu_aio_unref(acb);
1006         return NULL;
1007     }
1008     memset(acb->task, 0, sizeof(struct scsi_task));
1009 
1010     switch (acb->ioh->dxfer_direction) {
1011     case SG_DXFER_TO_DEV:
1012         acb->task->xfer_dir = SCSI_XFER_WRITE;
1013         break;
1014     case SG_DXFER_FROM_DEV:
1015         acb->task->xfer_dir = SCSI_XFER_READ;
1016         break;
1017     default:
1018         acb->task->xfer_dir = SCSI_XFER_NONE;
1019         break;
1020     }
1021 
1022     acb->task->cdb_size = acb->ioh->cmd_len;
1023     memcpy(&acb->task->cdb[0], acb->ioh->cmdp, acb->ioh->cmd_len);
1024     acb->task->expxferlen = acb->ioh->dxfer_len;
1025 
1026     data.size = 0;
1027     if (acb->task->xfer_dir == SCSI_XFER_WRITE) {
1028         if (acb->ioh->iovec_count == 0) {
1029             data.data = acb->ioh->dxferp;
1030             data.size = acb->ioh->dxfer_len;
1031         } else {
1032             scsi_task_set_iov_out(acb->task,
1033                                  (struct scsi_iovec *) acb->ioh->dxferp,
1034                                  acb->ioh->iovec_count);
1035         }
1036     }
1037 
1038     if (iscsi_scsi_command_async(iscsi, iscsilun->lun, acb->task,
1039                                  iscsi_aio_ioctl_cb,
1040                                  (data.size > 0) ? &data : NULL,
1041                                  acb) != 0) {
1042         scsi_free_scsi_task(acb->task);
1043         qemu_aio_unref(acb);
1044         return NULL;
1045     }
1046 
1047     /* tell libiscsi to read straight into the buffer we got from ioctl */
1048     if (acb->task->xfer_dir == SCSI_XFER_READ) {
1049         if (acb->ioh->iovec_count == 0) {
1050             scsi_task_add_data_in_buffer(acb->task,
1051                                          acb->ioh->dxfer_len,
1052                                          acb->ioh->dxferp);
1053         } else {
1054             scsi_task_set_iov_in(acb->task,
1055                                  (struct scsi_iovec *) acb->ioh->dxferp,
1056                                  acb->ioh->iovec_count);
1057         }
1058     }
1059 
1060     iscsi_set_events(iscsilun);
1061 
1062     return &acb->common;
1063 }
1064 
1065 #endif
1066 
1067 static int64_t
1068 iscsi_getlength(BlockDriverState *bs)
1069 {
1070     IscsiLun *iscsilun = bs->opaque;
1071     int64_t len;
1072 
1073     len  = iscsilun->num_blocks;
1074     len *= iscsilun->block_size;
1075 
1076     return len;
1077 }
1078 
1079 static int
1080 coroutine_fn iscsi_co_pdiscard(BlockDriverState *bs, int64_t offset, int count)
1081 {
1082     IscsiLun *iscsilun = bs->opaque;
1083     struct IscsiTask iTask;
1084     struct unmap_list list;
1085 
1086     assert(is_byte_request_lun_aligned(offset, count, iscsilun));
1087 
1088     if (!iscsilun->lbp.lbpu) {
1089         /* UNMAP is not supported by the target */
1090         return 0;
1091     }
1092 
1093     list.lba = offset / iscsilun->block_size;
1094     list.num = count / iscsilun->block_size;
1095 
1096     iscsi_co_init_iscsitask(iscsilun, &iTask);
1097 retry:
1098     if (iscsi_unmap_task(iscsilun->iscsi, iscsilun->lun, 0, 0, &list, 1,
1099                          iscsi_co_generic_cb, &iTask) == NULL) {
1100         return -ENOMEM;
1101     }
1102 
1103     while (!iTask.complete) {
1104         iscsi_set_events(iscsilun);
1105         qemu_coroutine_yield();
1106     }
1107 
1108     if (iTask.task != NULL) {
1109         scsi_free_scsi_task(iTask.task);
1110         iTask.task = NULL;
1111     }
1112 
1113     if (iTask.do_retry) {
1114         iTask.complete = 0;
1115         goto retry;
1116     }
1117 
1118     if (iTask.status == SCSI_STATUS_CHECK_CONDITION) {
1119         /* the target might fail with a check condition if it
1120            is not happy with the alignment of the UNMAP request
1121            we silently fail in this case */
1122         return 0;
1123     }
1124 
1125     if (iTask.status != SCSI_STATUS_GOOD) {
1126         return iTask.err_code;
1127     }
1128 
1129     iscsi_allocmap_set_invalid(iscsilun, offset >> BDRV_SECTOR_BITS,
1130                                count >> BDRV_SECTOR_BITS);
1131 
1132     return 0;
1133 }
1134 
1135 static int
1136 coroutine_fn iscsi_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset,
1137                                     int count, BdrvRequestFlags flags)
1138 {
1139     IscsiLun *iscsilun = bs->opaque;
1140     struct IscsiTask iTask;
1141     uint64_t lba;
1142     uint32_t nb_blocks;
1143     bool use_16_for_ws = iscsilun->use_16_for_rw;
1144 
1145     if (!is_byte_request_lun_aligned(offset, count, iscsilun)) {
1146         return -ENOTSUP;
1147     }
1148 
1149     if (flags & BDRV_REQ_MAY_UNMAP) {
1150         if (!use_16_for_ws && !iscsilun->lbp.lbpws10) {
1151             /* WRITESAME10 with UNMAP is unsupported try WRITESAME16 */
1152             use_16_for_ws = true;
1153         }
1154         if (use_16_for_ws && !iscsilun->lbp.lbpws) {
1155             /* WRITESAME16 with UNMAP is not supported by the target,
1156              * fall back and try WRITESAME10/16 without UNMAP */
1157             flags &= ~BDRV_REQ_MAY_UNMAP;
1158             use_16_for_ws = iscsilun->use_16_for_rw;
1159         }
1160     }
1161 
1162     if (!(flags & BDRV_REQ_MAY_UNMAP) && !iscsilun->has_write_same) {
1163         /* WRITESAME without UNMAP is not supported by the target */
1164         return -ENOTSUP;
1165     }
1166 
1167     lba = offset / iscsilun->block_size;
1168     nb_blocks = count / iscsilun->block_size;
1169 
1170     if (iscsilun->zeroblock == NULL) {
1171         iscsilun->zeroblock = g_try_malloc0(iscsilun->block_size);
1172         if (iscsilun->zeroblock == NULL) {
1173             return -ENOMEM;
1174         }
1175     }
1176 
1177     iscsi_co_init_iscsitask(iscsilun, &iTask);
1178 retry:
1179     if (use_16_for_ws) {
1180         iTask.task = iscsi_writesame16_task(iscsilun->iscsi, iscsilun->lun, lba,
1181                                             iscsilun->zeroblock, iscsilun->block_size,
1182                                             nb_blocks, 0, !!(flags & BDRV_REQ_MAY_UNMAP),
1183                                             0, 0, iscsi_co_generic_cb, &iTask);
1184     } else {
1185         iTask.task = iscsi_writesame10_task(iscsilun->iscsi, iscsilun->lun, lba,
1186                                             iscsilun->zeroblock, iscsilun->block_size,
1187                                             nb_blocks, 0, !!(flags & BDRV_REQ_MAY_UNMAP),
1188                                             0, 0, iscsi_co_generic_cb, &iTask);
1189     }
1190     if (iTask.task == NULL) {
1191         return -ENOMEM;
1192     }
1193 
1194     while (!iTask.complete) {
1195         iscsi_set_events(iscsilun);
1196         qemu_coroutine_yield();
1197     }
1198 
1199     if (iTask.status == SCSI_STATUS_CHECK_CONDITION &&
1200         iTask.task->sense.key == SCSI_SENSE_ILLEGAL_REQUEST &&
1201         (iTask.task->sense.ascq == SCSI_SENSE_ASCQ_INVALID_OPERATION_CODE ||
1202          iTask.task->sense.ascq == SCSI_SENSE_ASCQ_INVALID_FIELD_IN_CDB)) {
1203         /* WRITE SAME is not supported by the target */
1204         iscsilun->has_write_same = false;
1205         scsi_free_scsi_task(iTask.task);
1206         return -ENOTSUP;
1207     }
1208 
1209     if (iTask.task != NULL) {
1210         scsi_free_scsi_task(iTask.task);
1211         iTask.task = NULL;
1212     }
1213 
1214     if (iTask.do_retry) {
1215         iTask.complete = 0;
1216         goto retry;
1217     }
1218 
1219     if (iTask.status != SCSI_STATUS_GOOD) {
1220         iscsi_allocmap_set_invalid(iscsilun, offset >> BDRV_SECTOR_BITS,
1221                                    count >> BDRV_SECTOR_BITS);
1222         return iTask.err_code;
1223     }
1224 
1225     if (flags & BDRV_REQ_MAY_UNMAP) {
1226         iscsi_allocmap_set_invalid(iscsilun, offset >> BDRV_SECTOR_BITS,
1227                                    count >> BDRV_SECTOR_BITS);
1228     } else {
1229         iscsi_allocmap_set_allocated(iscsilun, offset >> BDRV_SECTOR_BITS,
1230                                      count >> BDRV_SECTOR_BITS);
1231     }
1232 
1233     return 0;
1234 }
1235 
1236 static void parse_chap(struct iscsi_context *iscsi, const char *target,
1237                        Error **errp)
1238 {
1239     QemuOptsList *list;
1240     QemuOpts *opts;
1241     const char *user = NULL;
1242     const char *password = NULL;
1243     const char *secretid;
1244     char *secret = NULL;
1245 
1246     list = qemu_find_opts("iscsi");
1247     if (!list) {
1248         return;
1249     }
1250 
1251     opts = qemu_opts_find(list, target);
1252     if (opts == NULL) {
1253         opts = QTAILQ_FIRST(&list->head);
1254         if (!opts) {
1255             return;
1256         }
1257     }
1258 
1259     user = qemu_opt_get(opts, "user");
1260     if (!user) {
1261         return;
1262     }
1263 
1264     secretid = qemu_opt_get(opts, "password-secret");
1265     password = qemu_opt_get(opts, "password");
1266     if (secretid && password) {
1267         error_setg(errp, "'password' and 'password-secret' properties are "
1268                    "mutually exclusive");
1269         return;
1270     }
1271     if (secretid) {
1272         secret = qcrypto_secret_lookup_as_utf8(secretid, errp);
1273         if (!secret) {
1274             return;
1275         }
1276         password = secret;
1277     } else if (!password) {
1278         error_setg(errp, "CHAP username specified but no password was given");
1279         return;
1280     }
1281 
1282     if (iscsi_set_initiator_username_pwd(iscsi, user, password)) {
1283         error_setg(errp, "Failed to set initiator username and password");
1284     }
1285 
1286     g_free(secret);
1287 }
1288 
1289 static void parse_header_digest(struct iscsi_context *iscsi, const char *target,
1290                                 Error **errp)
1291 {
1292     QemuOptsList *list;
1293     QemuOpts *opts;
1294     const char *digest = NULL;
1295 
1296     list = qemu_find_opts("iscsi");
1297     if (!list) {
1298         return;
1299     }
1300 
1301     opts = qemu_opts_find(list, target);
1302     if (opts == NULL) {
1303         opts = QTAILQ_FIRST(&list->head);
1304         if (!opts) {
1305             return;
1306         }
1307     }
1308 
1309     digest = qemu_opt_get(opts, "header-digest");
1310     if (!digest) {
1311         return;
1312     }
1313 
1314     if (!strcmp(digest, "CRC32C")) {
1315         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_CRC32C);
1316     } else if (!strcmp(digest, "NONE")) {
1317         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE);
1318     } else if (!strcmp(digest, "CRC32C-NONE")) {
1319         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_CRC32C_NONE);
1320     } else if (!strcmp(digest, "NONE-CRC32C")) {
1321         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
1322     } else {
1323         error_setg(errp, "Invalid header-digest setting : %s", digest);
1324     }
1325 }
1326 
1327 static char *parse_initiator_name(const char *target)
1328 {
1329     QemuOptsList *list;
1330     QemuOpts *opts;
1331     const char *name;
1332     char *iscsi_name;
1333     UuidInfo *uuid_info;
1334 
1335     list = qemu_find_opts("iscsi");
1336     if (list) {
1337         opts = qemu_opts_find(list, target);
1338         if (!opts) {
1339             opts = QTAILQ_FIRST(&list->head);
1340         }
1341         if (opts) {
1342             name = qemu_opt_get(opts, "initiator-name");
1343             if (name) {
1344                 return g_strdup(name);
1345             }
1346         }
1347     }
1348 
1349     uuid_info = qmp_query_uuid(NULL);
1350     if (strcmp(uuid_info->UUID, UUID_NONE) == 0) {
1351         name = qemu_get_vm_name();
1352     } else {
1353         name = uuid_info->UUID;
1354     }
1355     iscsi_name = g_strdup_printf("iqn.2008-11.org.linux-kvm%s%s",
1356                                  name ? ":" : "", name ? name : "");
1357     qapi_free_UuidInfo(uuid_info);
1358     return iscsi_name;
1359 }
1360 
1361 static int parse_timeout(const char *target)
1362 {
1363     QemuOptsList *list;
1364     QemuOpts *opts;
1365     const char *timeout;
1366 
1367     list = qemu_find_opts("iscsi");
1368     if (list) {
1369         opts = qemu_opts_find(list, target);
1370         if (!opts) {
1371             opts = QTAILQ_FIRST(&list->head);
1372         }
1373         if (opts) {
1374             timeout = qemu_opt_get(opts, "timeout");
1375             if (timeout) {
1376                 return atoi(timeout);
1377             }
1378         }
1379     }
1380 
1381     return 0;
1382 }
1383 
1384 static void iscsi_nop_timed_event(void *opaque)
1385 {
1386     IscsiLun *iscsilun = opaque;
1387 
1388     if (iscsi_get_nops_in_flight(iscsilun->iscsi) >= MAX_NOP_FAILURES) {
1389         error_report("iSCSI: NOP timeout. Reconnecting...");
1390         iscsilun->request_timed_out = true;
1391     } else if (iscsi_nop_out_async(iscsilun->iscsi, NULL, NULL, 0, NULL) != 0) {
1392         error_report("iSCSI: failed to sent NOP-Out. Disabling NOP messages.");
1393         return;
1394     }
1395 
1396     timer_mod(iscsilun->nop_timer, qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + NOP_INTERVAL);
1397     iscsi_set_events(iscsilun);
1398 }
1399 
1400 static void iscsi_readcapacity_sync(IscsiLun *iscsilun, Error **errp)
1401 {
1402     struct scsi_task *task = NULL;
1403     struct scsi_readcapacity10 *rc10 = NULL;
1404     struct scsi_readcapacity16 *rc16 = NULL;
1405     int retries = ISCSI_CMD_RETRIES;
1406 
1407     do {
1408         if (task != NULL) {
1409             scsi_free_scsi_task(task);
1410             task = NULL;
1411         }
1412 
1413         switch (iscsilun->type) {
1414         case TYPE_DISK:
1415             task = iscsi_readcapacity16_sync(iscsilun->iscsi, iscsilun->lun);
1416             if (task != NULL && task->status == SCSI_STATUS_GOOD) {
1417                 rc16 = scsi_datain_unmarshall(task);
1418                 if (rc16 == NULL) {
1419                     error_setg(errp, "iSCSI: Failed to unmarshall readcapacity16 data.");
1420                 } else {
1421                     iscsilun->block_size = rc16->block_length;
1422                     iscsilun->num_blocks = rc16->returned_lba + 1;
1423                     iscsilun->lbpme = !!rc16->lbpme;
1424                     iscsilun->lbprz = !!rc16->lbprz;
1425                     iscsilun->use_16_for_rw = (rc16->returned_lba > 0xffffffff);
1426                 }
1427                 break;
1428             }
1429             if (task != NULL && task->status == SCSI_STATUS_CHECK_CONDITION
1430                 && task->sense.key == SCSI_SENSE_UNIT_ATTENTION) {
1431                 break;
1432             }
1433             /* Fall through and try READ CAPACITY(10) instead.  */
1434         case TYPE_ROM:
1435             task = iscsi_readcapacity10_sync(iscsilun->iscsi, iscsilun->lun, 0, 0);
1436             if (task != NULL && task->status == SCSI_STATUS_GOOD) {
1437                 rc10 = scsi_datain_unmarshall(task);
1438                 if (rc10 == NULL) {
1439                     error_setg(errp, "iSCSI: Failed to unmarshall readcapacity10 data.");
1440                 } else {
1441                     iscsilun->block_size = rc10->block_size;
1442                     if (rc10->lba == 0) {
1443                         /* blank disk loaded */
1444                         iscsilun->num_blocks = 0;
1445                     } else {
1446                         iscsilun->num_blocks = rc10->lba + 1;
1447                     }
1448                 }
1449             }
1450             break;
1451         default:
1452             return;
1453         }
1454     } while (task != NULL && task->status == SCSI_STATUS_CHECK_CONDITION
1455              && task->sense.key == SCSI_SENSE_UNIT_ATTENTION
1456              && retries-- > 0);
1457 
1458     if (task == NULL || task->status != SCSI_STATUS_GOOD) {
1459         error_setg(errp, "iSCSI: failed to send readcapacity10/16 command");
1460     } else if (!iscsilun->block_size ||
1461                iscsilun->block_size % BDRV_SECTOR_SIZE) {
1462         error_setg(errp, "iSCSI: the target returned an invalid "
1463                    "block size of %d.", iscsilun->block_size);
1464     }
1465     if (task) {
1466         scsi_free_scsi_task(task);
1467     }
1468 }
1469 
1470 /* TODO Convert to fine grained options */
1471 static QemuOptsList runtime_opts = {
1472     .name = "iscsi",
1473     .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
1474     .desc = {
1475         {
1476             .name = "filename",
1477             .type = QEMU_OPT_STRING,
1478             .help = "URL to the iscsi image",
1479         },
1480         { /* end of list */ }
1481     },
1482 };
1483 
1484 static struct scsi_task *iscsi_do_inquiry(struct iscsi_context *iscsi, int lun,
1485                                           int evpd, int pc, void **inq, Error **errp)
1486 {
1487     int full_size;
1488     struct scsi_task *task = NULL;
1489     task = iscsi_inquiry_sync(iscsi, lun, evpd, pc, 64);
1490     if (task == NULL || task->status != SCSI_STATUS_GOOD) {
1491         goto fail;
1492     }
1493     full_size = scsi_datain_getfullsize(task);
1494     if (full_size > task->datain.size) {
1495         scsi_free_scsi_task(task);
1496 
1497         /* we need more data for the full list */
1498         task = iscsi_inquiry_sync(iscsi, lun, evpd, pc, full_size);
1499         if (task == NULL || task->status != SCSI_STATUS_GOOD) {
1500             goto fail;
1501         }
1502     }
1503 
1504     *inq = scsi_datain_unmarshall(task);
1505     if (*inq == NULL) {
1506         error_setg(errp, "iSCSI: failed to unmarshall inquiry datain blob");
1507         goto fail_with_err;
1508     }
1509 
1510     return task;
1511 
1512 fail:
1513     error_setg(errp, "iSCSI: Inquiry command failed : %s",
1514                iscsi_get_error(iscsi));
1515 fail_with_err:
1516     if (task != NULL) {
1517         scsi_free_scsi_task(task);
1518     }
1519     return NULL;
1520 }
1521 
1522 static void iscsi_detach_aio_context(BlockDriverState *bs)
1523 {
1524     IscsiLun *iscsilun = bs->opaque;
1525 
1526     aio_set_fd_handler(iscsilun->aio_context, iscsi_get_fd(iscsilun->iscsi),
1527                        false, NULL, NULL, NULL);
1528     iscsilun->events = 0;
1529 
1530     if (iscsilun->nop_timer) {
1531         timer_del(iscsilun->nop_timer);
1532         timer_free(iscsilun->nop_timer);
1533         iscsilun->nop_timer = NULL;
1534     }
1535     if (iscsilun->event_timer) {
1536         timer_del(iscsilun->event_timer);
1537         timer_free(iscsilun->event_timer);
1538         iscsilun->event_timer = NULL;
1539     }
1540 }
1541 
1542 static void iscsi_attach_aio_context(BlockDriverState *bs,
1543                                      AioContext *new_context)
1544 {
1545     IscsiLun *iscsilun = bs->opaque;
1546 
1547     iscsilun->aio_context = new_context;
1548     iscsi_set_events(iscsilun);
1549 
1550     /* Set up a timer for sending out iSCSI NOPs */
1551     iscsilun->nop_timer = aio_timer_new(iscsilun->aio_context,
1552                                         QEMU_CLOCK_REALTIME, SCALE_MS,
1553                                         iscsi_nop_timed_event, iscsilun);
1554     timer_mod(iscsilun->nop_timer,
1555               qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + NOP_INTERVAL);
1556 
1557     /* Set up a timer for periodic calls to iscsi_set_events and to
1558      * scan for command timeout */
1559     iscsilun->event_timer = aio_timer_new(iscsilun->aio_context,
1560                                           QEMU_CLOCK_REALTIME, SCALE_MS,
1561                                           iscsi_timed_check_events, iscsilun);
1562     timer_mod(iscsilun->event_timer,
1563               qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + EVENT_INTERVAL);
1564 }
1565 
1566 static void iscsi_modesense_sync(IscsiLun *iscsilun)
1567 {
1568     struct scsi_task *task;
1569     struct scsi_mode_sense *ms = NULL;
1570     iscsilun->write_protected = false;
1571     iscsilun->dpofua = false;
1572 
1573     task = iscsi_modesense6_sync(iscsilun->iscsi, iscsilun->lun,
1574                                  1, SCSI_MODESENSE_PC_CURRENT,
1575                                  0x3F, 0, 255);
1576     if (task == NULL) {
1577         error_report("iSCSI: Failed to send MODE_SENSE(6) command: %s",
1578                      iscsi_get_error(iscsilun->iscsi));
1579         goto out;
1580     }
1581 
1582     if (task->status != SCSI_STATUS_GOOD) {
1583         error_report("iSCSI: Failed MODE_SENSE(6), LUN assumed writable");
1584         goto out;
1585     }
1586     ms = scsi_datain_unmarshall(task);
1587     if (!ms) {
1588         error_report("iSCSI: Failed to unmarshall MODE_SENSE(6) data: %s",
1589                      iscsi_get_error(iscsilun->iscsi));
1590         goto out;
1591     }
1592     iscsilun->write_protected = ms->device_specific_parameter & 0x80;
1593     iscsilun->dpofua          = ms->device_specific_parameter & 0x10;
1594 
1595 out:
1596     if (task) {
1597         scsi_free_scsi_task(task);
1598     }
1599 }
1600 
1601 /*
1602  * We support iscsi url's on the form
1603  * iscsi://[<username>%<password>@]<host>[:<port>]/<targetname>/<lun>
1604  */
1605 static int iscsi_open(BlockDriverState *bs, QDict *options, int flags,
1606                       Error **errp)
1607 {
1608     IscsiLun *iscsilun = bs->opaque;
1609     struct iscsi_context *iscsi = NULL;
1610     struct iscsi_url *iscsi_url = NULL;
1611     struct scsi_task *task = NULL;
1612     struct scsi_inquiry_standard *inq = NULL;
1613     struct scsi_inquiry_supported_pages *inq_vpd;
1614     char *initiator_name = NULL;
1615     QemuOpts *opts;
1616     Error *local_err = NULL;
1617     const char *filename;
1618     int i, ret = 0, timeout = 0;
1619 
1620     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
1621     qemu_opts_absorb_qdict(opts, options, &local_err);
1622     if (local_err) {
1623         error_propagate(errp, local_err);
1624         ret = -EINVAL;
1625         goto out;
1626     }
1627 
1628     filename = qemu_opt_get(opts, "filename");
1629 
1630     iscsi_url = iscsi_parse_full_url(iscsi, filename);
1631     if (iscsi_url == NULL) {
1632         error_setg(errp, "Failed to parse URL : %s", filename);
1633         ret = -EINVAL;
1634         goto out;
1635     }
1636 
1637     memset(iscsilun, 0, sizeof(IscsiLun));
1638 
1639     initiator_name = parse_initiator_name(iscsi_url->target);
1640 
1641     iscsi = iscsi_create_context(initiator_name);
1642     if (iscsi == NULL) {
1643         error_setg(errp, "iSCSI: Failed to create iSCSI context.");
1644         ret = -ENOMEM;
1645         goto out;
1646     }
1647 #if LIBISCSI_API_VERSION >= (20160603)
1648     if (iscsi_init_transport(iscsi, iscsi_url->transport)) {
1649         error_setg(errp, ("Error initializing transport."));
1650         ret = -EINVAL;
1651         goto out;
1652     }
1653 #endif
1654     if (iscsi_set_targetname(iscsi, iscsi_url->target)) {
1655         error_setg(errp, "iSCSI: Failed to set target name.");
1656         ret = -EINVAL;
1657         goto out;
1658     }
1659 
1660     if (iscsi_url->user[0] != '\0') {
1661         ret = iscsi_set_initiator_username_pwd(iscsi, iscsi_url->user,
1662                                               iscsi_url->passwd);
1663         if (ret != 0) {
1664             error_setg(errp, "Failed to set initiator username and password");
1665             ret = -EINVAL;
1666             goto out;
1667         }
1668     }
1669 
1670     /* check if we got CHAP username/password via the options */
1671     parse_chap(iscsi, iscsi_url->target, &local_err);
1672     if (local_err != NULL) {
1673         error_propagate(errp, local_err);
1674         ret = -EINVAL;
1675         goto out;
1676     }
1677 
1678     if (iscsi_set_session_type(iscsi, ISCSI_SESSION_NORMAL) != 0) {
1679         error_setg(errp, "iSCSI: Failed to set session type to normal.");
1680         ret = -EINVAL;
1681         goto out;
1682     }
1683 
1684     iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
1685 
1686     /* check if we got HEADER_DIGEST via the options */
1687     parse_header_digest(iscsi, iscsi_url->target, &local_err);
1688     if (local_err != NULL) {
1689         error_propagate(errp, local_err);
1690         ret = -EINVAL;
1691         goto out;
1692     }
1693 
1694     /* timeout handling is broken in libiscsi before 1.15.0 */
1695     timeout = parse_timeout(iscsi_url->target);
1696 #if LIBISCSI_API_VERSION >= 20150621
1697     iscsi_set_timeout(iscsi, timeout);
1698 #else
1699     if (timeout) {
1700         error_report("iSCSI: ignoring timeout value for libiscsi <1.15.0");
1701     }
1702 #endif
1703 
1704     if (iscsi_full_connect_sync(iscsi, iscsi_url->portal, iscsi_url->lun) != 0) {
1705         error_setg(errp, "iSCSI: Failed to connect to LUN : %s",
1706             iscsi_get_error(iscsi));
1707         ret = -EINVAL;
1708         goto out;
1709     }
1710 
1711     iscsilun->iscsi = iscsi;
1712     iscsilun->aio_context = bdrv_get_aio_context(bs);
1713     iscsilun->lun   = iscsi_url->lun;
1714     iscsilun->has_write_same = true;
1715 
1716     task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 0, 0,
1717                             (void **) &inq, errp);
1718     if (task == NULL) {
1719         ret = -EINVAL;
1720         goto out;
1721     }
1722     iscsilun->type = inq->periperal_device_type;
1723     scsi_free_scsi_task(task);
1724     task = NULL;
1725 
1726     iscsi_modesense_sync(iscsilun);
1727     if (iscsilun->dpofua) {
1728         bs->supported_write_flags = BDRV_REQ_FUA;
1729     }
1730     bs->supported_zero_flags = BDRV_REQ_MAY_UNMAP;
1731 
1732     /* Check the write protect flag of the LUN if we want to write */
1733     if (iscsilun->type == TYPE_DISK && (flags & BDRV_O_RDWR) &&
1734         iscsilun->write_protected) {
1735         error_setg(errp, "Cannot open a write protected LUN as read-write");
1736         ret = -EACCES;
1737         goto out;
1738     }
1739 
1740     iscsi_readcapacity_sync(iscsilun, &local_err);
1741     if (local_err != NULL) {
1742         error_propagate(errp, local_err);
1743         ret = -EINVAL;
1744         goto out;
1745     }
1746     bs->total_sectors = sector_lun2qemu(iscsilun->num_blocks, iscsilun);
1747 
1748     /* We don't have any emulation for devices other than disks and CD-ROMs, so
1749      * this must be sg ioctl compatible. We force it to be sg, otherwise qemu
1750      * will try to read from the device to guess the image format.
1751      */
1752     if (iscsilun->type != TYPE_DISK && iscsilun->type != TYPE_ROM) {
1753         bs->sg = true;
1754     }
1755 
1756     task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 1,
1757                             SCSI_INQUIRY_PAGECODE_SUPPORTED_VPD_PAGES,
1758                             (void **) &inq_vpd, errp);
1759     if (task == NULL) {
1760         ret = -EINVAL;
1761         goto out;
1762     }
1763     for (i = 0; i < inq_vpd->num_pages; i++) {
1764         struct scsi_task *inq_task;
1765         struct scsi_inquiry_logical_block_provisioning *inq_lbp;
1766         struct scsi_inquiry_block_limits *inq_bl;
1767         switch (inq_vpd->pages[i]) {
1768         case SCSI_INQUIRY_PAGECODE_LOGICAL_BLOCK_PROVISIONING:
1769             inq_task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 1,
1770                                         SCSI_INQUIRY_PAGECODE_LOGICAL_BLOCK_PROVISIONING,
1771                                         (void **) &inq_lbp, errp);
1772             if (inq_task == NULL) {
1773                 ret = -EINVAL;
1774                 goto out;
1775             }
1776             memcpy(&iscsilun->lbp, inq_lbp,
1777                    sizeof(struct scsi_inquiry_logical_block_provisioning));
1778             scsi_free_scsi_task(inq_task);
1779             break;
1780         case SCSI_INQUIRY_PAGECODE_BLOCK_LIMITS:
1781             inq_task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 1,
1782                                     SCSI_INQUIRY_PAGECODE_BLOCK_LIMITS,
1783                                     (void **) &inq_bl, errp);
1784             if (inq_task == NULL) {
1785                 ret = -EINVAL;
1786                 goto out;
1787             }
1788             memcpy(&iscsilun->bl, inq_bl,
1789                    sizeof(struct scsi_inquiry_block_limits));
1790             scsi_free_scsi_task(inq_task);
1791             break;
1792         default:
1793             break;
1794         }
1795     }
1796     scsi_free_scsi_task(task);
1797     task = NULL;
1798 
1799     iscsi_attach_aio_context(bs, iscsilun->aio_context);
1800 
1801     /* Guess the internal cluster (page) size of the iscsi target by the means
1802      * of opt_unmap_gran. Transfer the unmap granularity only if it has a
1803      * reasonable size */
1804     if (iscsilun->bl.opt_unmap_gran * iscsilun->block_size >= 4 * 1024 &&
1805         iscsilun->bl.opt_unmap_gran * iscsilun->block_size <= 16 * 1024 * 1024) {
1806         iscsilun->cluster_sectors = (iscsilun->bl.opt_unmap_gran *
1807                                      iscsilun->block_size) >> BDRV_SECTOR_BITS;
1808         if (iscsilun->lbprz) {
1809             ret = iscsi_allocmap_init(iscsilun, bs->open_flags);
1810         }
1811     }
1812 
1813 out:
1814     qemu_opts_del(opts);
1815     g_free(initiator_name);
1816     if (iscsi_url != NULL) {
1817         iscsi_destroy_url(iscsi_url);
1818     }
1819     if (task != NULL) {
1820         scsi_free_scsi_task(task);
1821     }
1822 
1823     if (ret) {
1824         if (iscsi != NULL) {
1825             if (iscsi_is_logged_in(iscsi)) {
1826                 iscsi_logout_sync(iscsi);
1827             }
1828             iscsi_destroy_context(iscsi);
1829         }
1830         memset(iscsilun, 0, sizeof(IscsiLun));
1831     }
1832     return ret;
1833 }
1834 
1835 static void iscsi_close(BlockDriverState *bs)
1836 {
1837     IscsiLun *iscsilun = bs->opaque;
1838     struct iscsi_context *iscsi = iscsilun->iscsi;
1839 
1840     iscsi_detach_aio_context(bs);
1841     if (iscsi_is_logged_in(iscsi)) {
1842         iscsi_logout_sync(iscsi);
1843     }
1844     iscsi_destroy_context(iscsi);
1845     g_free(iscsilun->zeroblock);
1846     iscsi_allocmap_free(iscsilun);
1847     memset(iscsilun, 0, sizeof(IscsiLun));
1848 }
1849 
1850 static void iscsi_refresh_limits(BlockDriverState *bs, Error **errp)
1851 {
1852     /* We don't actually refresh here, but just return data queried in
1853      * iscsi_open(): iscsi targets don't change their limits. */
1854 
1855     IscsiLun *iscsilun = bs->opaque;
1856     uint64_t max_xfer_len = iscsilun->use_16_for_rw ? 0xffffffff : 0xffff;
1857     unsigned int block_size = MAX(BDRV_SECTOR_SIZE, iscsilun->block_size);
1858 
1859     assert(iscsilun->block_size >= BDRV_SECTOR_SIZE || bs->sg);
1860 
1861     bs->bl.request_alignment = block_size;
1862 
1863     if (iscsilun->bl.max_xfer_len) {
1864         max_xfer_len = MIN(max_xfer_len, iscsilun->bl.max_xfer_len);
1865     }
1866 
1867     if (max_xfer_len * block_size < INT_MAX) {
1868         bs->bl.max_transfer = max_xfer_len * iscsilun->block_size;
1869     }
1870 
1871     if (iscsilun->lbp.lbpu) {
1872         if (iscsilun->bl.max_unmap < 0xffffffff / block_size) {
1873             bs->bl.max_pdiscard =
1874                 iscsilun->bl.max_unmap * iscsilun->block_size;
1875         }
1876         bs->bl.pdiscard_alignment =
1877             iscsilun->bl.opt_unmap_gran * iscsilun->block_size;
1878     } else {
1879         bs->bl.pdiscard_alignment = iscsilun->block_size;
1880     }
1881 
1882     if (iscsilun->bl.max_ws_len < 0xffffffff / block_size) {
1883         bs->bl.max_pwrite_zeroes =
1884             iscsilun->bl.max_ws_len * iscsilun->block_size;
1885     }
1886     if (iscsilun->lbp.lbpws) {
1887         bs->bl.pwrite_zeroes_alignment =
1888             iscsilun->bl.opt_unmap_gran * iscsilun->block_size;
1889     } else {
1890         bs->bl.pwrite_zeroes_alignment = iscsilun->block_size;
1891     }
1892     if (iscsilun->bl.opt_xfer_len &&
1893         iscsilun->bl.opt_xfer_len < INT_MAX / block_size) {
1894         bs->bl.opt_transfer = pow2floor(iscsilun->bl.opt_xfer_len *
1895                                         iscsilun->block_size);
1896     }
1897 }
1898 
1899 /* Note that this will not re-establish a connection with an iSCSI target - it
1900  * is effectively a NOP.  */
1901 static int iscsi_reopen_prepare(BDRVReopenState *state,
1902                                 BlockReopenQueue *queue, Error **errp)
1903 {
1904     IscsiLun *iscsilun = state->bs->opaque;
1905 
1906     if (state->flags & BDRV_O_RDWR && iscsilun->write_protected) {
1907         error_setg(errp, "Cannot open a write protected LUN as read-write");
1908         return -EACCES;
1909     }
1910     return 0;
1911 }
1912 
1913 static void iscsi_reopen_commit(BDRVReopenState *reopen_state)
1914 {
1915     IscsiLun *iscsilun = reopen_state->bs->opaque;
1916 
1917     /* the cache.direct status might have changed */
1918     if (iscsilun->allocmap != NULL) {
1919         iscsi_allocmap_init(iscsilun, reopen_state->flags);
1920     }
1921 }
1922 
1923 static int iscsi_truncate(BlockDriverState *bs, int64_t offset)
1924 {
1925     IscsiLun *iscsilun = bs->opaque;
1926     Error *local_err = NULL;
1927 
1928     if (iscsilun->type != TYPE_DISK) {
1929         return -ENOTSUP;
1930     }
1931 
1932     iscsi_readcapacity_sync(iscsilun, &local_err);
1933     if (local_err != NULL) {
1934         error_free(local_err);
1935         return -EIO;
1936     }
1937 
1938     if (offset > iscsi_getlength(bs)) {
1939         return -EINVAL;
1940     }
1941 
1942     if (iscsilun->allocmap != NULL) {
1943         iscsi_allocmap_init(iscsilun, bs->open_flags);
1944     }
1945 
1946     return 0;
1947 }
1948 
1949 static int iscsi_create(const char *filename, QemuOpts *opts, Error **errp)
1950 {
1951     int ret = 0;
1952     int64_t total_size = 0;
1953     BlockDriverState *bs;
1954     IscsiLun *iscsilun = NULL;
1955     QDict *bs_options;
1956 
1957     bs = bdrv_new();
1958 
1959     /* Read out options */
1960     total_size = DIV_ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
1961                               BDRV_SECTOR_SIZE);
1962     bs->opaque = g_new0(struct IscsiLun, 1);
1963     iscsilun = bs->opaque;
1964 
1965     bs_options = qdict_new();
1966     qdict_put(bs_options, "filename", qstring_from_str(filename));
1967     ret = iscsi_open(bs, bs_options, 0, NULL);
1968     QDECREF(bs_options);
1969 
1970     if (ret != 0) {
1971         goto out;
1972     }
1973     iscsi_detach_aio_context(bs);
1974     if (iscsilun->type != TYPE_DISK) {
1975         ret = -ENODEV;
1976         goto out;
1977     }
1978     if (bs->total_sectors < total_size) {
1979         ret = -ENOSPC;
1980         goto out;
1981     }
1982 
1983     ret = 0;
1984 out:
1985     if (iscsilun->iscsi != NULL) {
1986         iscsi_destroy_context(iscsilun->iscsi);
1987     }
1988     g_free(bs->opaque);
1989     bs->opaque = NULL;
1990     bdrv_unref(bs);
1991     return ret;
1992 }
1993 
1994 static int iscsi_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
1995 {
1996     IscsiLun *iscsilun = bs->opaque;
1997     bdi->unallocated_blocks_are_zero = iscsilun->lbprz;
1998     bdi->can_write_zeroes_with_unmap = iscsilun->lbprz && iscsilun->lbp.lbpws;
1999     bdi->cluster_size = iscsilun->cluster_sectors * BDRV_SECTOR_SIZE;
2000     return 0;
2001 }
2002 
2003 static void iscsi_invalidate_cache(BlockDriverState *bs,
2004                                    Error **errp)
2005 {
2006     IscsiLun *iscsilun = bs->opaque;
2007     iscsi_allocmap_invalidate(iscsilun);
2008 }
2009 
2010 static QemuOptsList iscsi_create_opts = {
2011     .name = "iscsi-create-opts",
2012     .head = QTAILQ_HEAD_INITIALIZER(iscsi_create_opts.head),
2013     .desc = {
2014         {
2015             .name = BLOCK_OPT_SIZE,
2016             .type = QEMU_OPT_SIZE,
2017             .help = "Virtual disk size"
2018         },
2019         { /* end of list */ }
2020     }
2021 };
2022 
2023 static BlockDriver bdrv_iscsi = {
2024     .format_name     = "iscsi",
2025     .protocol_name   = "iscsi",
2026 
2027     .instance_size   = sizeof(IscsiLun),
2028     .bdrv_needs_filename = true,
2029     .bdrv_file_open  = iscsi_open,
2030     .bdrv_close      = iscsi_close,
2031     .bdrv_create     = iscsi_create,
2032     .create_opts     = &iscsi_create_opts,
2033     .bdrv_reopen_prepare   = iscsi_reopen_prepare,
2034     .bdrv_reopen_commit    = iscsi_reopen_commit,
2035     .bdrv_invalidate_cache = iscsi_invalidate_cache,
2036 
2037     .bdrv_getlength  = iscsi_getlength,
2038     .bdrv_get_info   = iscsi_get_info,
2039     .bdrv_truncate   = iscsi_truncate,
2040     .bdrv_refresh_limits = iscsi_refresh_limits,
2041 
2042     .bdrv_co_get_block_status = iscsi_co_get_block_status,
2043     .bdrv_co_pdiscard      = iscsi_co_pdiscard,
2044     .bdrv_co_pwrite_zeroes = iscsi_co_pwrite_zeroes,
2045     .bdrv_co_readv         = iscsi_co_readv,
2046     .bdrv_co_writev_flags  = iscsi_co_writev_flags,
2047     .bdrv_co_flush_to_disk = iscsi_co_flush,
2048 
2049 #ifdef __linux__
2050     .bdrv_aio_ioctl   = iscsi_aio_ioctl,
2051 #endif
2052 
2053     .bdrv_detach_aio_context = iscsi_detach_aio_context,
2054     .bdrv_attach_aio_context = iscsi_attach_aio_context,
2055 };
2056 
2057 #if LIBISCSI_API_VERSION >= (20160603)
2058 static BlockDriver bdrv_iser = {
2059     .format_name     = "iser",
2060     .protocol_name   = "iser",
2061 
2062     .instance_size   = sizeof(IscsiLun),
2063     .bdrv_needs_filename = true,
2064     .bdrv_file_open  = iscsi_open,
2065     .bdrv_close      = iscsi_close,
2066     .bdrv_create     = iscsi_create,
2067     .create_opts     = &iscsi_create_opts,
2068     .bdrv_reopen_prepare   = iscsi_reopen_prepare,
2069     .bdrv_reopen_commit    = iscsi_reopen_commit,
2070     .bdrv_invalidate_cache = iscsi_invalidate_cache,
2071 
2072     .bdrv_getlength  = iscsi_getlength,
2073     .bdrv_get_info   = iscsi_get_info,
2074     .bdrv_truncate   = iscsi_truncate,
2075     .bdrv_refresh_limits = iscsi_refresh_limits,
2076 
2077     .bdrv_co_get_block_status = iscsi_co_get_block_status,
2078     .bdrv_co_pdiscard      = iscsi_co_pdiscard,
2079     .bdrv_co_pwrite_zeroes = iscsi_co_pwrite_zeroes,
2080     .bdrv_co_readv         = iscsi_co_readv,
2081     .bdrv_co_writev_flags  = iscsi_co_writev_flags,
2082     .bdrv_co_flush_to_disk = iscsi_co_flush,
2083 
2084 #ifdef __linux__
2085     .bdrv_aio_ioctl   = iscsi_aio_ioctl,
2086 #endif
2087 
2088     .bdrv_detach_aio_context = iscsi_detach_aio_context,
2089     .bdrv_attach_aio_context = iscsi_attach_aio_context,
2090 };
2091 #endif
2092 
2093 static void iscsi_block_init(void)
2094 {
2095     bdrv_register(&bdrv_iscsi);
2096 #if LIBISCSI_API_VERSION >= (20160603)
2097     bdrv_register(&bdrv_iser);
2098 #endif
2099 }
2100 
2101 block_init(iscsi_block_init);
2102