xref: /openbmc/qemu/block/iscsi.c (revision 438c78da)
1 /*
2  * QEMU Block driver for iSCSI images
3  *
4  * Copyright (c) 2010-2011 Ronnie Sahlberg <ronniesahlberg@gmail.com>
5  * Copyright (c) 2012-2017 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/config-file.h"
32 #include "qemu/error-report.h"
33 #include "qemu/bitops.h"
34 #include "qemu/bitmap.h"
35 #include "block/block_int.h"
36 #include "block/qdict.h"
37 #include "scsi/constants.h"
38 #include "qemu/iov.h"
39 #include "qemu/option.h"
40 #include "qemu/uuid.h"
41 #include "qapi/error.h"
42 #include "qapi/qapi-commands-misc.h"
43 #include "qapi/qmp/qdict.h"
44 #include "qapi/qmp/qstring.h"
45 #include "crypto/secret.h"
46 #include "scsi/utils.h"
47 #include "trace.h"
48 
49 /* Conflict between scsi/utils.h and libiscsi! :( */
50 #define SCSI_XFER_NONE ISCSI_XFER_NONE
51 #include <iscsi/iscsi.h>
52 #include <iscsi/scsi-lowlevel.h>
53 #undef SCSI_XFER_NONE
54 QEMU_BUILD_BUG_ON((int)SCSI_XFER_NONE != (int)ISCSI_XFER_NONE);
55 
56 #ifdef __linux__
57 #include <scsi/sg.h>
58 #endif
59 
60 typedef struct IscsiLun {
61     struct iscsi_context *iscsi;
62     AioContext *aio_context;
63     int lun;
64     enum scsi_inquiry_peripheral_device_type type;
65     int block_size;
66     uint64_t num_blocks;
67     int events;
68     QEMUTimer *nop_timer;
69     QEMUTimer *event_timer;
70     QemuMutex mutex;
71     struct scsi_inquiry_logical_block_provisioning lbp;
72     struct scsi_inquiry_block_limits bl;
73     struct scsi_inquiry_device_designator *dd;
74     unsigned char *zeroblock;
75     /* The allocmap tracks which clusters (pages) on the iSCSI target are
76      * allocated and which are not. In case a target returns zeros for
77      * unallocated pages (iscsilun->lprz) we can directly return zeros instead
78      * of reading zeros over the wire if a read request falls within an
79      * unallocated block. As there are 3 possible states we need 2 bitmaps to
80      * track. allocmap_valid keeps track if QEMU's information about a page is
81      * valid. allocmap tracks if a page is allocated or not. In case QEMU has no
82      * valid information about a page the corresponding allocmap entry should be
83      * switched to unallocated as well to force a new lookup of the allocation
84      * status as lookups are generally skipped if a page is suspect to be
85      * allocated. If a iSCSI target is opened with cache.direct = on the
86      * allocmap_valid does not exist turning all cached information invalid so
87      * that a fresh lookup is made for any page even if allocmap entry returns
88      * it's unallocated. */
89     unsigned long *allocmap;
90     unsigned long *allocmap_valid;
91     long allocmap_size;
92     int cluster_size;
93     bool use_16_for_rw;
94     bool write_protected;
95     bool lbpme;
96     bool lbprz;
97     bool dpofua;
98     bool has_write_same;
99     bool request_timed_out;
100 } IscsiLun;
101 
102 typedef struct IscsiTask {
103     int status;
104     int complete;
105     int retries;
106     int do_retry;
107     struct scsi_task *task;
108     Coroutine *co;
109     IscsiLun *iscsilun;
110     QEMUTimer retry_timer;
111     int err_code;
112     char *err_str;
113 } IscsiTask;
114 
115 typedef struct IscsiAIOCB {
116     BlockAIOCB common;
117     QEMUBH *bh;
118     IscsiLun *iscsilun;
119     struct scsi_task *task;
120     uint8_t *buf;
121     int status;
122     int64_t sector_num;
123     int nb_sectors;
124     int ret;
125 #ifdef __linux__
126     sg_io_hdr_t *ioh;
127 #endif
128 } IscsiAIOCB;
129 
130 /* libiscsi uses time_t so its enough to process events every second */
131 #define EVENT_INTERVAL 1000
132 #define NOP_INTERVAL 5000
133 #define MAX_NOP_FAILURES 3
134 #define ISCSI_CMD_RETRIES ARRAY_SIZE(iscsi_retry_times)
135 static const unsigned iscsi_retry_times[] = {8, 32, 128, 512, 2048, 8192, 32768};
136 
137 /* this threshold is a trade-off knob to choose between
138  * the potential additional overhead of an extra GET_LBA_STATUS request
139  * vs. unnecessarily reading a lot of zero sectors over the wire.
140  * If a read request is greater or equal than ISCSI_CHECKALLOC_THRES
141  * sectors we check the allocation status of the area covered by the
142  * request first if the allocationmap indicates that the area might be
143  * unallocated. */
144 #define ISCSI_CHECKALLOC_THRES 64
145 
146 static void
147 iscsi_bh_cb(void *p)
148 {
149     IscsiAIOCB *acb = p;
150 
151     qemu_bh_delete(acb->bh);
152 
153     g_free(acb->buf);
154     acb->buf = NULL;
155 
156     acb->common.cb(acb->common.opaque, acb->status);
157 
158     if (acb->task != NULL) {
159         scsi_free_scsi_task(acb->task);
160         acb->task = NULL;
161     }
162 
163     qemu_aio_unref(acb);
164 }
165 
166 static void
167 iscsi_schedule_bh(IscsiAIOCB *acb)
168 {
169     if (acb->bh) {
170         return;
171     }
172     acb->bh = aio_bh_new(acb->iscsilun->aio_context, iscsi_bh_cb, acb);
173     qemu_bh_schedule(acb->bh);
174 }
175 
176 static void iscsi_co_generic_bh_cb(void *opaque)
177 {
178     struct IscsiTask *iTask = opaque;
179 
180     iTask->complete = 1;
181     aio_co_wake(iTask->co);
182 }
183 
184 static void iscsi_retry_timer_expired(void *opaque)
185 {
186     struct IscsiTask *iTask = opaque;
187     iTask->complete = 1;
188     if (iTask->co) {
189         aio_co_wake(iTask->co);
190     }
191 }
192 
193 static inline unsigned exp_random(double mean)
194 {
195     return -mean * log((double)rand() / RAND_MAX);
196 }
197 
198 /* SCSI_SENSE_ASCQ_INVALID_FIELD_IN_PARAMETER_LIST was introduced in
199  * libiscsi 1.10.0, together with other constants we need.  Use it as
200  * a hint that we have to define them ourselves if needed, to keep the
201  * minimum required libiscsi version at 1.9.0.  We use an ASCQ macro for
202  * the test because SCSI_STATUS_* is an enum.
203  *
204  * To guard against future changes where SCSI_SENSE_ASCQ_* also becomes
205  * an enum, check against the LIBISCSI_API_VERSION macro, which was
206  * introduced in 1.11.0.  If it is present, there is no need to define
207  * anything.
208  */
209 #if !defined(SCSI_SENSE_ASCQ_INVALID_FIELD_IN_PARAMETER_LIST) && \
210     !defined(LIBISCSI_API_VERSION)
211 #define SCSI_STATUS_TASK_SET_FULL                          0x28
212 #define SCSI_STATUS_TIMEOUT                                0x0f000002
213 #define SCSI_SENSE_ASCQ_INVALID_FIELD_IN_PARAMETER_LIST    0x2600
214 #define SCSI_SENSE_ASCQ_PARAMETER_LIST_LENGTH_ERROR        0x1a00
215 #endif
216 
217 #ifndef LIBISCSI_API_VERSION
218 #define LIBISCSI_API_VERSION 20130701
219 #endif
220 
221 static int iscsi_translate_sense(struct scsi_sense *sense)
222 {
223     return - scsi_sense_to_errno(sense->key,
224                                  (sense->ascq & 0xFF00) >> 8,
225                                  sense->ascq & 0xFF);
226 }
227 
228 /* Called (via iscsi_service) with QemuMutex held.  */
229 static void
230 iscsi_co_generic_cb(struct iscsi_context *iscsi, int status,
231                         void *command_data, void *opaque)
232 {
233     struct IscsiTask *iTask = opaque;
234     struct scsi_task *task = command_data;
235 
236     iTask->status = status;
237     iTask->do_retry = 0;
238     iTask->task = task;
239 
240     if (status != SCSI_STATUS_GOOD) {
241         if (iTask->retries++ < ISCSI_CMD_RETRIES) {
242             if (status == SCSI_STATUS_CHECK_CONDITION
243                 && task->sense.key == SCSI_SENSE_UNIT_ATTENTION) {
244                 error_report("iSCSI CheckCondition: %s",
245                              iscsi_get_error(iscsi));
246                 iTask->do_retry = 1;
247                 goto out;
248             }
249             if (status == SCSI_STATUS_BUSY ||
250                 status == SCSI_STATUS_TIMEOUT ||
251                 status == SCSI_STATUS_TASK_SET_FULL) {
252                 unsigned retry_time =
253                     exp_random(iscsi_retry_times[iTask->retries - 1]);
254                 if (status == SCSI_STATUS_TIMEOUT) {
255                     /* make sure the request is rescheduled AFTER the
256                      * reconnect is initiated */
257                     retry_time = EVENT_INTERVAL * 2;
258                     iTask->iscsilun->request_timed_out = true;
259                 }
260                 error_report("iSCSI Busy/TaskSetFull/TimeOut"
261                              " (retry #%u in %u ms): %s",
262                              iTask->retries, retry_time,
263                              iscsi_get_error(iscsi));
264                 aio_timer_init(iTask->iscsilun->aio_context,
265                                &iTask->retry_timer, QEMU_CLOCK_REALTIME,
266                                SCALE_MS, iscsi_retry_timer_expired, iTask);
267                 timer_mod(&iTask->retry_timer,
268                           qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + retry_time);
269                 iTask->do_retry = 1;
270                 return;
271             }
272         }
273         iTask->err_code = iscsi_translate_sense(&task->sense);
274         iTask->err_str = g_strdup(iscsi_get_error(iscsi));
275     }
276 
277 out:
278     if (iTask->co) {
279         aio_bh_schedule_oneshot(iTask->iscsilun->aio_context,
280                                  iscsi_co_generic_bh_cb, iTask);
281     } else {
282         iTask->complete = 1;
283     }
284 }
285 
286 static void iscsi_co_init_iscsitask(IscsiLun *iscsilun, struct IscsiTask *iTask)
287 {
288     *iTask = (struct IscsiTask) {
289         .co         = qemu_coroutine_self(),
290         .iscsilun   = iscsilun,
291     };
292 }
293 
294 static void
295 iscsi_abort_task_cb(struct iscsi_context *iscsi, int status, void *command_data,
296                     void *private_data)
297 {
298     IscsiAIOCB *acb = private_data;
299 
300     acb->status = -ECANCELED;
301     iscsi_schedule_bh(acb);
302 }
303 
304 static void
305 iscsi_aio_cancel(BlockAIOCB *blockacb)
306 {
307     IscsiAIOCB *acb = (IscsiAIOCB *)blockacb;
308     IscsiLun *iscsilun = acb->iscsilun;
309 
310     if (acb->status != -EINPROGRESS) {
311         return;
312     }
313 
314     /* send a task mgmt call to the target to cancel the task on the target */
315     iscsi_task_mgmt_abort_task_async(iscsilun->iscsi, acb->task,
316                                      iscsi_abort_task_cb, acb);
317 
318 }
319 
320 static const AIOCBInfo iscsi_aiocb_info = {
321     .aiocb_size         = sizeof(IscsiAIOCB),
322     .cancel_async       = iscsi_aio_cancel,
323 };
324 
325 
326 static void iscsi_process_read(void *arg);
327 static void iscsi_process_write(void *arg);
328 
329 /* Called with QemuMutex held.  */
330 static void
331 iscsi_set_events(IscsiLun *iscsilun)
332 {
333     struct iscsi_context *iscsi = iscsilun->iscsi;
334     int ev = iscsi_which_events(iscsi);
335 
336     if (ev != iscsilun->events) {
337         aio_set_fd_handler(iscsilun->aio_context, iscsi_get_fd(iscsi),
338                            false,
339                            (ev & POLLIN) ? iscsi_process_read : NULL,
340                            (ev & POLLOUT) ? iscsi_process_write : NULL,
341                            NULL,
342                            iscsilun);
343         iscsilun->events = ev;
344     }
345 }
346 
347 static void iscsi_timed_check_events(void *opaque)
348 {
349     IscsiLun *iscsilun = opaque;
350 
351     /* check for timed out requests */
352     iscsi_service(iscsilun->iscsi, 0);
353 
354     if (iscsilun->request_timed_out) {
355         iscsilun->request_timed_out = false;
356         iscsi_reconnect(iscsilun->iscsi);
357     }
358 
359     /* newer versions of libiscsi may return zero events. Ensure we are able
360      * to return to service once this situation changes. */
361     iscsi_set_events(iscsilun);
362 
363     timer_mod(iscsilun->event_timer,
364               qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + EVENT_INTERVAL);
365 }
366 
367 static void
368 iscsi_process_read(void *arg)
369 {
370     IscsiLun *iscsilun = arg;
371     struct iscsi_context *iscsi = iscsilun->iscsi;
372 
373     qemu_mutex_lock(&iscsilun->mutex);
374     iscsi_service(iscsi, POLLIN);
375     iscsi_set_events(iscsilun);
376     qemu_mutex_unlock(&iscsilun->mutex);
377 }
378 
379 static void
380 iscsi_process_write(void *arg)
381 {
382     IscsiLun *iscsilun = arg;
383     struct iscsi_context *iscsi = iscsilun->iscsi;
384 
385     qemu_mutex_lock(&iscsilun->mutex);
386     iscsi_service(iscsi, POLLOUT);
387     iscsi_set_events(iscsilun);
388     qemu_mutex_unlock(&iscsilun->mutex);
389 }
390 
391 static int64_t sector_lun2qemu(int64_t sector, IscsiLun *iscsilun)
392 {
393     return sector * iscsilun->block_size / BDRV_SECTOR_SIZE;
394 }
395 
396 static int64_t sector_qemu2lun(int64_t sector, IscsiLun *iscsilun)
397 {
398     return sector * BDRV_SECTOR_SIZE / iscsilun->block_size;
399 }
400 
401 static bool is_byte_request_lun_aligned(int64_t offset, int count,
402                                         IscsiLun *iscsilun)
403 {
404     if (offset % iscsilun->block_size || count % iscsilun->block_size) {
405         error_report("iSCSI misaligned request: "
406                      "iscsilun->block_size %u, offset %" PRIi64
407                      ", count %d",
408                      iscsilun->block_size, offset, count);
409         return false;
410     }
411     return true;
412 }
413 
414 static bool is_sector_request_lun_aligned(int64_t sector_num, int nb_sectors,
415                                           IscsiLun *iscsilun)
416 {
417     assert(nb_sectors <= BDRV_REQUEST_MAX_SECTORS);
418     return is_byte_request_lun_aligned(sector_num << BDRV_SECTOR_BITS,
419                                        nb_sectors << BDRV_SECTOR_BITS,
420                                        iscsilun);
421 }
422 
423 static void iscsi_allocmap_free(IscsiLun *iscsilun)
424 {
425     g_free(iscsilun->allocmap);
426     g_free(iscsilun->allocmap_valid);
427     iscsilun->allocmap = NULL;
428     iscsilun->allocmap_valid = NULL;
429 }
430 
431 
432 static int iscsi_allocmap_init(IscsiLun *iscsilun, int open_flags)
433 {
434     iscsi_allocmap_free(iscsilun);
435 
436     assert(iscsilun->cluster_size);
437     iscsilun->allocmap_size =
438         DIV_ROUND_UP(iscsilun->num_blocks * iscsilun->block_size,
439                      iscsilun->cluster_size);
440 
441     iscsilun->allocmap = bitmap_try_new(iscsilun->allocmap_size);
442     if (!iscsilun->allocmap) {
443         return -ENOMEM;
444     }
445 
446     if (open_flags & BDRV_O_NOCACHE) {
447         /* when cache.direct = on all allocmap entries are
448          * treated as invalid to force a relookup of the block
449          * status on every read request */
450         return 0;
451     }
452 
453     iscsilun->allocmap_valid = bitmap_try_new(iscsilun->allocmap_size);
454     if (!iscsilun->allocmap_valid) {
455         /* if we are under memory pressure free the allocmap as well */
456         iscsi_allocmap_free(iscsilun);
457         return -ENOMEM;
458     }
459 
460     return 0;
461 }
462 
463 static void
464 iscsi_allocmap_update(IscsiLun *iscsilun, int64_t offset,
465                       int64_t bytes, bool allocated, bool valid)
466 {
467     int64_t cl_num_expanded, nb_cls_expanded, cl_num_shrunk, nb_cls_shrunk;
468 
469     if (iscsilun->allocmap == NULL) {
470         return;
471     }
472     /* expand to entirely contain all affected clusters */
473     assert(iscsilun->cluster_size);
474     cl_num_expanded = offset / iscsilun->cluster_size;
475     nb_cls_expanded = DIV_ROUND_UP(offset + bytes,
476                                    iscsilun->cluster_size) - cl_num_expanded;
477     /* shrink to touch only completely contained clusters */
478     cl_num_shrunk = DIV_ROUND_UP(offset, iscsilun->cluster_size);
479     nb_cls_shrunk = (offset + bytes) / iscsilun->cluster_size - cl_num_shrunk;
480     if (allocated) {
481         bitmap_set(iscsilun->allocmap, cl_num_expanded, nb_cls_expanded);
482     } else {
483         if (nb_cls_shrunk > 0) {
484             bitmap_clear(iscsilun->allocmap, cl_num_shrunk, nb_cls_shrunk);
485         }
486     }
487 
488     if (iscsilun->allocmap_valid == NULL) {
489         return;
490     }
491     if (valid) {
492         if (nb_cls_shrunk > 0) {
493             bitmap_set(iscsilun->allocmap_valid, cl_num_shrunk, nb_cls_shrunk);
494         }
495     } else {
496         bitmap_clear(iscsilun->allocmap_valid, cl_num_expanded,
497                      nb_cls_expanded);
498     }
499 }
500 
501 static void
502 iscsi_allocmap_set_allocated(IscsiLun *iscsilun, int64_t offset,
503                              int64_t bytes)
504 {
505     iscsi_allocmap_update(iscsilun, offset, bytes, true, true);
506 }
507 
508 static void
509 iscsi_allocmap_set_unallocated(IscsiLun *iscsilun, int64_t offset,
510                                int64_t bytes)
511 {
512     /* Note: if cache.direct=on the fifth argument to iscsi_allocmap_update
513      * is ignored, so this will in effect be an iscsi_allocmap_set_invalid.
514      */
515     iscsi_allocmap_update(iscsilun, offset, bytes, false, true);
516 }
517 
518 static void iscsi_allocmap_set_invalid(IscsiLun *iscsilun, int64_t offset,
519                                        int64_t bytes)
520 {
521     iscsi_allocmap_update(iscsilun, offset, bytes, false, false);
522 }
523 
524 static void iscsi_allocmap_invalidate(IscsiLun *iscsilun)
525 {
526     if (iscsilun->allocmap) {
527         bitmap_zero(iscsilun->allocmap, iscsilun->allocmap_size);
528     }
529     if (iscsilun->allocmap_valid) {
530         bitmap_zero(iscsilun->allocmap_valid, iscsilun->allocmap_size);
531     }
532 }
533 
534 static inline bool
535 iscsi_allocmap_is_allocated(IscsiLun *iscsilun, int64_t offset,
536                             int64_t bytes)
537 {
538     unsigned long size;
539     if (iscsilun->allocmap == NULL) {
540         return true;
541     }
542     assert(iscsilun->cluster_size);
543     size = DIV_ROUND_UP(offset + bytes, iscsilun->cluster_size);
544     return !(find_next_bit(iscsilun->allocmap, size,
545                            offset / iscsilun->cluster_size) == size);
546 }
547 
548 static inline bool iscsi_allocmap_is_valid(IscsiLun *iscsilun,
549                                            int64_t offset, int64_t bytes)
550 {
551     unsigned long size;
552     if (iscsilun->allocmap_valid == NULL) {
553         return false;
554     }
555     assert(iscsilun->cluster_size);
556     size = DIV_ROUND_UP(offset + bytes, iscsilun->cluster_size);
557     return (find_next_zero_bit(iscsilun->allocmap_valid, size,
558                                offset / iscsilun->cluster_size) == size);
559 }
560 
561 static void coroutine_fn iscsi_co_wait_for_task(IscsiTask *iTask,
562                                                 IscsiLun *iscsilun)
563 {
564     while (!iTask->complete) {
565         iscsi_set_events(iscsilun);
566         qemu_mutex_unlock(&iscsilun->mutex);
567         qemu_coroutine_yield();
568         qemu_mutex_lock(&iscsilun->mutex);
569     }
570 }
571 
572 static int coroutine_fn
573 iscsi_co_writev(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
574                 QEMUIOVector *iov, int flags)
575 {
576     IscsiLun *iscsilun = bs->opaque;
577     struct IscsiTask iTask;
578     uint64_t lba;
579     uint32_t num_sectors;
580     bool fua = flags & BDRV_REQ_FUA;
581     int r = 0;
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     qemu_mutex_lock(&iscsilun->mutex);
598 retry:
599     if (iscsilun->use_16_for_rw) {
600 #if LIBISCSI_API_VERSION >= (20160603)
601         iTask.task = iscsi_write16_iov_task(iscsilun->iscsi, iscsilun->lun, lba,
602                                             NULL, num_sectors * iscsilun->block_size,
603                                             iscsilun->block_size, 0, 0, fua, 0, 0,
604                                             iscsi_co_generic_cb, &iTask,
605                                             (struct scsi_iovec *)iov->iov, iov->niov);
606     } else {
607         iTask.task = iscsi_write10_iov_task(iscsilun->iscsi, iscsilun->lun, lba,
608                                             NULL, num_sectors * iscsilun->block_size,
609                                             iscsilun->block_size, 0, 0, fua, 0, 0,
610                                             iscsi_co_generic_cb, &iTask,
611                                             (struct scsi_iovec *)iov->iov, iov->niov);
612     }
613 #else
614         iTask.task = iscsi_write16_task(iscsilun->iscsi, iscsilun->lun, lba,
615                                         NULL, num_sectors * iscsilun->block_size,
616                                         iscsilun->block_size, 0, 0, fua, 0, 0,
617                                         iscsi_co_generic_cb, &iTask);
618     } else {
619         iTask.task = iscsi_write10_task(iscsilun->iscsi, iscsilun->lun, lba,
620                                         NULL, num_sectors * iscsilun->block_size,
621                                         iscsilun->block_size, 0, 0, fua, 0, 0,
622                                         iscsi_co_generic_cb, &iTask);
623     }
624 #endif
625     if (iTask.task == NULL) {
626         qemu_mutex_unlock(&iscsilun->mutex);
627         return -ENOMEM;
628     }
629 #if LIBISCSI_API_VERSION < (20160603)
630     scsi_task_set_iov_out(iTask.task, (struct scsi_iovec *) iov->iov,
631                           iov->niov);
632 #endif
633     iscsi_co_wait_for_task(&iTask, iscsilun);
634 
635     if (iTask.task != NULL) {
636         scsi_free_scsi_task(iTask.task);
637         iTask.task = NULL;
638     }
639 
640     if (iTask.do_retry) {
641         iTask.complete = 0;
642         goto retry;
643     }
644 
645     if (iTask.status != SCSI_STATUS_GOOD) {
646         iscsi_allocmap_set_invalid(iscsilun, sector_num * BDRV_SECTOR_SIZE,
647                                    nb_sectors * BDRV_SECTOR_SIZE);
648         error_report("iSCSI WRITE10/16 failed at lba %" PRIu64 ": %s", lba,
649                      iTask.err_str);
650         r = iTask.err_code;
651         goto out_unlock;
652     }
653 
654     iscsi_allocmap_set_allocated(iscsilun, sector_num * BDRV_SECTOR_SIZE,
655                                  nb_sectors * BDRV_SECTOR_SIZE);
656 
657 out_unlock:
658     qemu_mutex_unlock(&iscsilun->mutex);
659     g_free(iTask.err_str);
660     return r;
661 }
662 
663 
664 
665 static int coroutine_fn iscsi_co_block_status(BlockDriverState *bs,
666                                               bool want_zero, int64_t offset,
667                                               int64_t bytes, int64_t *pnum,
668                                               int64_t *map,
669                                               BlockDriverState **file)
670 {
671     IscsiLun *iscsilun = bs->opaque;
672     struct scsi_get_lba_status *lbas = NULL;
673     struct scsi_lba_status_descriptor *lbasd = NULL;
674     struct IscsiTask iTask;
675     uint64_t lba;
676     int ret;
677 
678     iscsi_co_init_iscsitask(iscsilun, &iTask);
679 
680     assert(QEMU_IS_ALIGNED(offset | bytes, iscsilun->block_size));
681 
682     /* default to all sectors allocated */
683     ret = BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID;
684     if (map) {
685         *map = offset;
686     }
687     *pnum = bytes;
688 
689     /* LUN does not support logical block provisioning */
690     if (!iscsilun->lbpme) {
691         goto out;
692     }
693 
694     lba = offset / iscsilun->block_size;
695 
696     qemu_mutex_lock(&iscsilun->mutex);
697 retry:
698     if (iscsi_get_lba_status_task(iscsilun->iscsi, iscsilun->lun,
699                                   lba, 8 + 16, iscsi_co_generic_cb,
700                                   &iTask) == NULL) {
701         ret = -ENOMEM;
702         goto out_unlock;
703     }
704     iscsi_co_wait_for_task(&iTask, iscsilun);
705 
706     if (iTask.do_retry) {
707         if (iTask.task != NULL) {
708             scsi_free_scsi_task(iTask.task);
709             iTask.task = NULL;
710         }
711         iTask.complete = 0;
712         goto retry;
713     }
714 
715     if (iTask.status != SCSI_STATUS_GOOD) {
716         /* in case the get_lba_status_callout fails (i.e.
717          * because the device is busy or the cmd is not
718          * supported) we pretend all blocks are allocated
719          * for backwards compatibility */
720         error_report("iSCSI GET_LBA_STATUS failed at lba %" PRIu64 ": %s",
721                      lba, iTask.err_str);
722         goto out_unlock;
723     }
724 
725     lbas = scsi_datain_unmarshall(iTask.task);
726     if (lbas == NULL) {
727         ret = -EIO;
728         goto out_unlock;
729     }
730 
731     lbasd = &lbas->descriptors[0];
732 
733     if (lba != lbasd->lba) {
734         ret = -EIO;
735         goto out_unlock;
736     }
737 
738     *pnum = (int64_t) lbasd->num_blocks * iscsilun->block_size;
739 
740     if (lbasd->provisioning == SCSI_PROVISIONING_TYPE_DEALLOCATED ||
741         lbasd->provisioning == SCSI_PROVISIONING_TYPE_ANCHORED) {
742         ret &= ~BDRV_BLOCK_DATA;
743         if (iscsilun->lbprz) {
744             ret |= BDRV_BLOCK_ZERO;
745         }
746     }
747 
748     if (ret & BDRV_BLOCK_ZERO) {
749         iscsi_allocmap_set_unallocated(iscsilun, offset, *pnum);
750     } else {
751         iscsi_allocmap_set_allocated(iscsilun, offset, *pnum);
752     }
753 
754     if (*pnum > bytes) {
755         *pnum = bytes;
756     }
757 out_unlock:
758     qemu_mutex_unlock(&iscsilun->mutex);
759     g_free(iTask.err_str);
760 out:
761     if (iTask.task != NULL) {
762         scsi_free_scsi_task(iTask.task);
763     }
764     if (ret > 0 && ret & BDRV_BLOCK_OFFSET_VALID && file) {
765         *file = bs;
766     }
767     return ret;
768 }
769 
770 static int coroutine_fn iscsi_co_readv(BlockDriverState *bs,
771                                        int64_t sector_num, int nb_sectors,
772                                        QEMUIOVector *iov)
773 {
774     IscsiLun *iscsilun = bs->opaque;
775     struct IscsiTask iTask;
776     uint64_t lba;
777     uint32_t num_sectors;
778     int r = 0;
779 
780     if (!is_sector_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
781         return -EINVAL;
782     }
783 
784     if (bs->bl.max_transfer) {
785         assert(nb_sectors << BDRV_SECTOR_BITS <= bs->bl.max_transfer);
786     }
787 
788     /* if cache.direct is off and we have a valid entry in our allocation map
789      * we can skip checking the block status and directly return zeroes if
790      * the request falls within an unallocated area */
791     if (iscsi_allocmap_is_valid(iscsilun, sector_num * BDRV_SECTOR_SIZE,
792                                 nb_sectors * BDRV_SECTOR_SIZE) &&
793         !iscsi_allocmap_is_allocated(iscsilun, sector_num * BDRV_SECTOR_SIZE,
794                                      nb_sectors * BDRV_SECTOR_SIZE)) {
795             qemu_iovec_memset(iov, 0, 0x00, iov->size);
796             return 0;
797     }
798 
799     if (nb_sectors >= ISCSI_CHECKALLOC_THRES &&
800         !iscsi_allocmap_is_valid(iscsilun, sector_num * BDRV_SECTOR_SIZE,
801                                  nb_sectors * BDRV_SECTOR_SIZE) &&
802         !iscsi_allocmap_is_allocated(iscsilun, sector_num * BDRV_SECTOR_SIZE,
803                                      nb_sectors * BDRV_SECTOR_SIZE)) {
804         int64_t pnum;
805         /* check the block status from the beginning of the cluster
806          * containing the start sector */
807         int64_t head;
808         int ret;
809 
810         assert(iscsilun->cluster_size);
811         head = (sector_num * BDRV_SECTOR_SIZE) % iscsilun->cluster_size;
812         ret = iscsi_co_block_status(bs, true,
813                                     sector_num * BDRV_SECTOR_SIZE - head,
814                                     BDRV_REQUEST_MAX_BYTES, &pnum, NULL, NULL);
815         if (ret < 0) {
816             return ret;
817         }
818         /* if the whole request falls into an unallocated area we can avoid
819          * reading and directly return zeroes instead */
820         if (ret & BDRV_BLOCK_ZERO &&
821             pnum >= nb_sectors * BDRV_SECTOR_SIZE + head) {
822             qemu_iovec_memset(iov, 0, 0x00, iov->size);
823             return 0;
824         }
825     }
826 
827     lba = sector_qemu2lun(sector_num, iscsilun);
828     num_sectors = sector_qemu2lun(nb_sectors, iscsilun);
829 
830     iscsi_co_init_iscsitask(iscsilun, &iTask);
831     qemu_mutex_lock(&iscsilun->mutex);
832 retry:
833     if (iscsilun->use_16_for_rw) {
834 #if LIBISCSI_API_VERSION >= (20160603)
835         iTask.task = iscsi_read16_iov_task(iscsilun->iscsi, iscsilun->lun, lba,
836                                            num_sectors * iscsilun->block_size,
837                                            iscsilun->block_size, 0, 0, 0, 0, 0,
838                                            iscsi_co_generic_cb, &iTask,
839                                            (struct scsi_iovec *)iov->iov, iov->niov);
840     } else {
841         iTask.task = iscsi_read10_iov_task(iscsilun->iscsi, iscsilun->lun, lba,
842                                            num_sectors * iscsilun->block_size,
843                                            iscsilun->block_size,
844                                            0, 0, 0, 0, 0,
845                                            iscsi_co_generic_cb, &iTask,
846                                            (struct scsi_iovec *)iov->iov, iov->niov);
847     }
848 #else
849         iTask.task = iscsi_read16_task(iscsilun->iscsi, iscsilun->lun, lba,
850                                        num_sectors * iscsilun->block_size,
851                                        iscsilun->block_size, 0, 0, 0, 0, 0,
852                                        iscsi_co_generic_cb, &iTask);
853     } else {
854         iTask.task = iscsi_read10_task(iscsilun->iscsi, iscsilun->lun, lba,
855                                        num_sectors * iscsilun->block_size,
856                                        iscsilun->block_size,
857                                        0, 0, 0, 0, 0,
858                                        iscsi_co_generic_cb, &iTask);
859     }
860 #endif
861     if (iTask.task == NULL) {
862         qemu_mutex_unlock(&iscsilun->mutex);
863         return -ENOMEM;
864     }
865 #if LIBISCSI_API_VERSION < (20160603)
866     scsi_task_set_iov_in(iTask.task, (struct scsi_iovec *) iov->iov, iov->niov);
867 #endif
868 
869     iscsi_co_wait_for_task(&iTask, iscsilun);
870     if (iTask.task != NULL) {
871         scsi_free_scsi_task(iTask.task);
872         iTask.task = NULL;
873     }
874 
875     if (iTask.do_retry) {
876         iTask.complete = 0;
877         goto retry;
878     }
879 
880     if (iTask.status != SCSI_STATUS_GOOD) {
881         error_report("iSCSI READ10/16 failed at lba %" PRIu64 ": %s",
882                      lba, iTask.err_str);
883         r = iTask.err_code;
884     }
885 
886     qemu_mutex_unlock(&iscsilun->mutex);
887     g_free(iTask.err_str);
888     return r;
889 }
890 
891 static int coroutine_fn iscsi_co_flush(BlockDriverState *bs)
892 {
893     IscsiLun *iscsilun = bs->opaque;
894     struct IscsiTask iTask;
895     int r = 0;
896 
897     iscsi_co_init_iscsitask(iscsilun, &iTask);
898     qemu_mutex_lock(&iscsilun->mutex);
899 retry:
900     if (iscsi_synchronizecache10_task(iscsilun->iscsi, iscsilun->lun, 0, 0, 0,
901                                       0, iscsi_co_generic_cb, &iTask) == NULL) {
902         qemu_mutex_unlock(&iscsilun->mutex);
903         return -ENOMEM;
904     }
905 
906     iscsi_co_wait_for_task(&iTask, iscsilun);
907 
908     if (iTask.task != NULL) {
909         scsi_free_scsi_task(iTask.task);
910         iTask.task = NULL;
911     }
912 
913     if (iTask.do_retry) {
914         iTask.complete = 0;
915         goto retry;
916     }
917 
918     if (iTask.status != SCSI_STATUS_GOOD) {
919         error_report("iSCSI SYNCHRONIZECACHE10 failed: %s", iTask.err_str);
920         r = iTask.err_code;
921     }
922 
923     qemu_mutex_unlock(&iscsilun->mutex);
924     g_free(iTask.err_str);
925     return r;
926 }
927 
928 #ifdef __linux__
929 /* Called (via iscsi_service) with QemuMutex held.  */
930 static void
931 iscsi_aio_ioctl_cb(struct iscsi_context *iscsi, int status,
932                      void *command_data, void *opaque)
933 {
934     IscsiAIOCB *acb = opaque;
935 
936     g_free(acb->buf);
937     acb->buf = NULL;
938 
939     acb->status = 0;
940     if (status < 0) {
941         error_report("Failed to ioctl(SG_IO) to iSCSI lun. %s",
942                      iscsi_get_error(iscsi));
943         acb->status = iscsi_translate_sense(&acb->task->sense);
944     }
945 
946     acb->ioh->driver_status = 0;
947     acb->ioh->host_status   = 0;
948     acb->ioh->resid         = 0;
949     acb->ioh->status        = status;
950 
951 #define SG_ERR_DRIVER_SENSE    0x08
952 
953     if (status == SCSI_STATUS_CHECK_CONDITION && acb->task->datain.size >= 2) {
954         int ss;
955 
956         acb->ioh->driver_status |= SG_ERR_DRIVER_SENSE;
957 
958         acb->ioh->sb_len_wr = acb->task->datain.size - 2;
959         ss = (acb->ioh->mx_sb_len >= acb->ioh->sb_len_wr) ?
960              acb->ioh->mx_sb_len : acb->ioh->sb_len_wr;
961         memcpy(acb->ioh->sbp, &acb->task->datain.data[2], ss);
962     }
963 
964     iscsi_schedule_bh(acb);
965 }
966 
967 static void iscsi_ioctl_bh_completion(void *opaque)
968 {
969     IscsiAIOCB *acb = opaque;
970 
971     qemu_bh_delete(acb->bh);
972     acb->common.cb(acb->common.opaque, acb->ret);
973     qemu_aio_unref(acb);
974 }
975 
976 static void iscsi_ioctl_handle_emulated(IscsiAIOCB *acb, int req, void *buf)
977 {
978     BlockDriverState *bs = acb->common.bs;
979     IscsiLun *iscsilun = bs->opaque;
980     int ret = 0;
981 
982     switch (req) {
983     case SG_GET_VERSION_NUM:
984         *(int *)buf = 30000;
985         break;
986     case SG_GET_SCSI_ID:
987         ((struct sg_scsi_id *)buf)->scsi_type = iscsilun->type;
988         break;
989     default:
990         ret = -EINVAL;
991     }
992     assert(!acb->bh);
993     acb->bh = aio_bh_new(bdrv_get_aio_context(bs),
994                          iscsi_ioctl_bh_completion, acb);
995     acb->ret = ret;
996     qemu_bh_schedule(acb->bh);
997 }
998 
999 static BlockAIOCB *iscsi_aio_ioctl(BlockDriverState *bs,
1000         unsigned long int req, void *buf,
1001         BlockCompletionFunc *cb, void *opaque)
1002 {
1003     IscsiLun *iscsilun = bs->opaque;
1004     struct iscsi_context *iscsi = iscsilun->iscsi;
1005     struct iscsi_data data;
1006     IscsiAIOCB *acb;
1007 
1008     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
1009 
1010     acb->iscsilun = iscsilun;
1011     acb->bh          = NULL;
1012     acb->status      = -EINPROGRESS;
1013     acb->buf         = NULL;
1014     acb->ioh         = buf;
1015 
1016     if (req != SG_IO) {
1017         iscsi_ioctl_handle_emulated(acb, req, buf);
1018         return &acb->common;
1019     }
1020 
1021     if (acb->ioh->cmd_len > SCSI_CDB_MAX_SIZE) {
1022         error_report("iSCSI: ioctl error CDB exceeds max size (%d > %d)",
1023                      acb->ioh->cmd_len, SCSI_CDB_MAX_SIZE);
1024         qemu_aio_unref(acb);
1025         return NULL;
1026     }
1027 
1028     acb->task = malloc(sizeof(struct scsi_task));
1029     if (acb->task == NULL) {
1030         error_report("iSCSI: Failed to allocate task for scsi command. %s",
1031                      iscsi_get_error(iscsi));
1032         qemu_aio_unref(acb);
1033         return NULL;
1034     }
1035     memset(acb->task, 0, sizeof(struct scsi_task));
1036 
1037     switch (acb->ioh->dxfer_direction) {
1038     case SG_DXFER_TO_DEV:
1039         acb->task->xfer_dir = SCSI_XFER_WRITE;
1040         break;
1041     case SG_DXFER_FROM_DEV:
1042         acb->task->xfer_dir = SCSI_XFER_READ;
1043         break;
1044     default:
1045         acb->task->xfer_dir = SCSI_XFER_NONE;
1046         break;
1047     }
1048 
1049     acb->task->cdb_size = acb->ioh->cmd_len;
1050     memcpy(&acb->task->cdb[0], acb->ioh->cmdp, acb->ioh->cmd_len);
1051     acb->task->expxferlen = acb->ioh->dxfer_len;
1052 
1053     data.size = 0;
1054     qemu_mutex_lock(&iscsilun->mutex);
1055     if (acb->task->xfer_dir == SCSI_XFER_WRITE) {
1056         if (acb->ioh->iovec_count == 0) {
1057             data.data = acb->ioh->dxferp;
1058             data.size = acb->ioh->dxfer_len;
1059         } else {
1060             scsi_task_set_iov_out(acb->task,
1061                                  (struct scsi_iovec *) acb->ioh->dxferp,
1062                                  acb->ioh->iovec_count);
1063         }
1064     }
1065 
1066     if (iscsi_scsi_command_async(iscsi, iscsilun->lun, acb->task,
1067                                  iscsi_aio_ioctl_cb,
1068                                  (data.size > 0) ? &data : NULL,
1069                                  acb) != 0) {
1070         qemu_mutex_unlock(&iscsilun->mutex);
1071         scsi_free_scsi_task(acb->task);
1072         qemu_aio_unref(acb);
1073         return NULL;
1074     }
1075 
1076     /* tell libiscsi to read straight into the buffer we got from ioctl */
1077     if (acb->task->xfer_dir == SCSI_XFER_READ) {
1078         if (acb->ioh->iovec_count == 0) {
1079             scsi_task_add_data_in_buffer(acb->task,
1080                                          acb->ioh->dxfer_len,
1081                                          acb->ioh->dxferp);
1082         } else {
1083             scsi_task_set_iov_in(acb->task,
1084                                  (struct scsi_iovec *) acb->ioh->dxferp,
1085                                  acb->ioh->iovec_count);
1086         }
1087     }
1088 
1089     iscsi_set_events(iscsilun);
1090     qemu_mutex_unlock(&iscsilun->mutex);
1091 
1092     return &acb->common;
1093 }
1094 
1095 #endif
1096 
1097 static int64_t
1098 iscsi_getlength(BlockDriverState *bs)
1099 {
1100     IscsiLun *iscsilun = bs->opaque;
1101     int64_t len;
1102 
1103     len  = iscsilun->num_blocks;
1104     len *= iscsilun->block_size;
1105 
1106     return len;
1107 }
1108 
1109 static int
1110 coroutine_fn iscsi_co_pdiscard(BlockDriverState *bs, int64_t offset, int bytes)
1111 {
1112     IscsiLun *iscsilun = bs->opaque;
1113     struct IscsiTask iTask;
1114     struct unmap_list list;
1115     int r = 0;
1116 
1117     if (!is_byte_request_lun_aligned(offset, bytes, iscsilun)) {
1118         return -ENOTSUP;
1119     }
1120 
1121     if (!iscsilun->lbp.lbpu) {
1122         /* UNMAP is not supported by the target */
1123         return 0;
1124     }
1125 
1126     list.lba = offset / iscsilun->block_size;
1127     list.num = bytes / iscsilun->block_size;
1128 
1129     iscsi_co_init_iscsitask(iscsilun, &iTask);
1130     qemu_mutex_lock(&iscsilun->mutex);
1131 retry:
1132     if (iscsi_unmap_task(iscsilun->iscsi, iscsilun->lun, 0, 0, &list, 1,
1133                          iscsi_co_generic_cb, &iTask) == NULL) {
1134         r = -ENOMEM;
1135         goto out_unlock;
1136     }
1137 
1138     iscsi_co_wait_for_task(&iTask, iscsilun);
1139 
1140     if (iTask.task != NULL) {
1141         scsi_free_scsi_task(iTask.task);
1142         iTask.task = NULL;
1143     }
1144 
1145     if (iTask.do_retry) {
1146         iTask.complete = 0;
1147         goto retry;
1148     }
1149 
1150     iscsi_allocmap_set_invalid(iscsilun, offset, bytes);
1151 
1152     if (iTask.status == SCSI_STATUS_CHECK_CONDITION) {
1153         /* the target might fail with a check condition if it
1154            is not happy with the alignment of the UNMAP request
1155            we silently fail in this case */
1156         goto out_unlock;
1157     }
1158 
1159     if (iTask.status != SCSI_STATUS_GOOD) {
1160         error_report("iSCSI UNMAP failed at lba %" PRIu64 ": %s",
1161                      list.lba, iTask.err_str);
1162         r = iTask.err_code;
1163         goto out_unlock;
1164     }
1165 
1166 out_unlock:
1167     qemu_mutex_unlock(&iscsilun->mutex);
1168     g_free(iTask.err_str);
1169     return r;
1170 }
1171 
1172 static int
1173 coroutine_fn iscsi_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset,
1174                                     int bytes, BdrvRequestFlags flags)
1175 {
1176     IscsiLun *iscsilun = bs->opaque;
1177     struct IscsiTask iTask;
1178     uint64_t lba;
1179     uint32_t nb_blocks;
1180     bool use_16_for_ws = iscsilun->use_16_for_rw;
1181     int r = 0;
1182 
1183     if (!is_byte_request_lun_aligned(offset, bytes, iscsilun)) {
1184         return -ENOTSUP;
1185     }
1186 
1187     if (flags & BDRV_REQ_MAY_UNMAP) {
1188         if (!use_16_for_ws && !iscsilun->lbp.lbpws10) {
1189             /* WRITESAME10 with UNMAP is unsupported try WRITESAME16 */
1190             use_16_for_ws = true;
1191         }
1192         if (use_16_for_ws && !iscsilun->lbp.lbpws) {
1193             /* WRITESAME16 with UNMAP is not supported by the target,
1194              * fall back and try WRITESAME10/16 without UNMAP */
1195             flags &= ~BDRV_REQ_MAY_UNMAP;
1196             use_16_for_ws = iscsilun->use_16_for_rw;
1197         }
1198     }
1199 
1200     if (!(flags & BDRV_REQ_MAY_UNMAP) && !iscsilun->has_write_same) {
1201         /* WRITESAME without UNMAP is not supported by the target */
1202         return -ENOTSUP;
1203     }
1204 
1205     lba = offset / iscsilun->block_size;
1206     nb_blocks = bytes / iscsilun->block_size;
1207 
1208     if (iscsilun->zeroblock == NULL) {
1209         iscsilun->zeroblock = g_try_malloc0(iscsilun->block_size);
1210         if (iscsilun->zeroblock == NULL) {
1211             return -ENOMEM;
1212         }
1213     }
1214 
1215     qemu_mutex_lock(&iscsilun->mutex);
1216     iscsi_co_init_iscsitask(iscsilun, &iTask);
1217 retry:
1218     if (use_16_for_ws) {
1219         iTask.task = iscsi_writesame16_task(iscsilun->iscsi, iscsilun->lun, lba,
1220                                             iscsilun->zeroblock, iscsilun->block_size,
1221                                             nb_blocks, 0, !!(flags & BDRV_REQ_MAY_UNMAP),
1222                                             0, 0, iscsi_co_generic_cb, &iTask);
1223     } else {
1224         iTask.task = iscsi_writesame10_task(iscsilun->iscsi, iscsilun->lun, lba,
1225                                             iscsilun->zeroblock, iscsilun->block_size,
1226                                             nb_blocks, 0, !!(flags & BDRV_REQ_MAY_UNMAP),
1227                                             0, 0, iscsi_co_generic_cb, &iTask);
1228     }
1229     if (iTask.task == NULL) {
1230         qemu_mutex_unlock(&iscsilun->mutex);
1231         return -ENOMEM;
1232     }
1233 
1234     iscsi_co_wait_for_task(&iTask, iscsilun);
1235 
1236     if (iTask.status == SCSI_STATUS_CHECK_CONDITION &&
1237         iTask.task->sense.key == SCSI_SENSE_ILLEGAL_REQUEST &&
1238         (iTask.task->sense.ascq == SCSI_SENSE_ASCQ_INVALID_OPERATION_CODE ||
1239          iTask.task->sense.ascq == SCSI_SENSE_ASCQ_INVALID_FIELD_IN_CDB)) {
1240         /* WRITE SAME is not supported by the target */
1241         iscsilun->has_write_same = false;
1242         scsi_free_scsi_task(iTask.task);
1243         r = -ENOTSUP;
1244         goto out_unlock;
1245     }
1246 
1247     if (iTask.task != NULL) {
1248         scsi_free_scsi_task(iTask.task);
1249         iTask.task = NULL;
1250     }
1251 
1252     if (iTask.do_retry) {
1253         iTask.complete = 0;
1254         goto retry;
1255     }
1256 
1257     if (iTask.status != SCSI_STATUS_GOOD) {
1258         iscsi_allocmap_set_invalid(iscsilun, offset, bytes);
1259         error_report("iSCSI WRITESAME10/16 failed at lba %" PRIu64 ": %s",
1260                      lba, iTask.err_str);
1261         r = iTask.err_code;
1262         goto out_unlock;
1263     }
1264 
1265     if (flags & BDRV_REQ_MAY_UNMAP) {
1266         iscsi_allocmap_set_invalid(iscsilun, offset, bytes);
1267     } else {
1268         iscsi_allocmap_set_allocated(iscsilun, offset, bytes);
1269     }
1270 
1271 out_unlock:
1272     qemu_mutex_unlock(&iscsilun->mutex);
1273     g_free(iTask.err_str);
1274     return r;
1275 }
1276 
1277 static void apply_chap(struct iscsi_context *iscsi, QemuOpts *opts,
1278                        Error **errp)
1279 {
1280     const char *user = NULL;
1281     const char *password = NULL;
1282     const char *secretid;
1283     char *secret = NULL;
1284 
1285     user = qemu_opt_get(opts, "user");
1286     if (!user) {
1287         return;
1288     }
1289 
1290     secretid = qemu_opt_get(opts, "password-secret");
1291     password = qemu_opt_get(opts, "password");
1292     if (secretid && password) {
1293         error_setg(errp, "'password' and 'password-secret' properties are "
1294                    "mutually exclusive");
1295         return;
1296     }
1297     if (secretid) {
1298         secret = qcrypto_secret_lookup_as_utf8(secretid, errp);
1299         if (!secret) {
1300             return;
1301         }
1302         password = secret;
1303     } else if (!password) {
1304         error_setg(errp, "CHAP username specified but no password was given");
1305         return;
1306     }
1307 
1308     if (iscsi_set_initiator_username_pwd(iscsi, user, password)) {
1309         error_setg(errp, "Failed to set initiator username and password");
1310     }
1311 
1312     g_free(secret);
1313 }
1314 
1315 static void apply_header_digest(struct iscsi_context *iscsi, QemuOpts *opts,
1316                                 Error **errp)
1317 {
1318     const char *digest = NULL;
1319 
1320     digest = qemu_opt_get(opts, "header-digest");
1321     if (!digest) {
1322         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
1323     } else if (!strcmp(digest, "crc32c")) {
1324         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_CRC32C);
1325     } else if (!strcmp(digest, "none")) {
1326         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE);
1327     } else if (!strcmp(digest, "crc32c-none")) {
1328         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_CRC32C_NONE);
1329     } else if (!strcmp(digest, "none-crc32c")) {
1330         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
1331     } else {
1332         error_setg(errp, "Invalid header-digest setting : %s", digest);
1333     }
1334 }
1335 
1336 static char *get_initiator_name(QemuOpts *opts)
1337 {
1338     const char *name;
1339     char *iscsi_name;
1340     UuidInfo *uuid_info;
1341 
1342     name = qemu_opt_get(opts, "initiator-name");
1343     if (name) {
1344         return g_strdup(name);
1345     }
1346 
1347     uuid_info = qmp_query_uuid(NULL);
1348     if (strcmp(uuid_info->UUID, UUID_NONE) == 0) {
1349         name = qemu_get_vm_name();
1350     } else {
1351         name = uuid_info->UUID;
1352     }
1353     iscsi_name = g_strdup_printf("iqn.2008-11.org.linux-kvm%s%s",
1354                                  name ? ":" : "", name ? name : "");
1355     qapi_free_UuidInfo(uuid_info);
1356     return iscsi_name;
1357 }
1358 
1359 static void iscsi_nop_timed_event(void *opaque)
1360 {
1361     IscsiLun *iscsilun = opaque;
1362 
1363     qemu_mutex_lock(&iscsilun->mutex);
1364     if (iscsi_get_nops_in_flight(iscsilun->iscsi) >= MAX_NOP_FAILURES) {
1365         error_report("iSCSI: NOP timeout. Reconnecting...");
1366         iscsilun->request_timed_out = true;
1367     } else if (iscsi_nop_out_async(iscsilun->iscsi, NULL, NULL, 0, NULL) != 0) {
1368         error_report("iSCSI: failed to sent NOP-Out. Disabling NOP messages.");
1369         goto out;
1370     }
1371 
1372     timer_mod(iscsilun->nop_timer, qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + NOP_INTERVAL);
1373     iscsi_set_events(iscsilun);
1374 
1375 out:
1376     qemu_mutex_unlock(&iscsilun->mutex);
1377 }
1378 
1379 static void iscsi_readcapacity_sync(IscsiLun *iscsilun, Error **errp)
1380 {
1381     struct scsi_task *task = NULL;
1382     struct scsi_readcapacity10 *rc10 = NULL;
1383     struct scsi_readcapacity16 *rc16 = NULL;
1384     int retries = ISCSI_CMD_RETRIES;
1385 
1386     do {
1387         if (task != NULL) {
1388             scsi_free_scsi_task(task);
1389             task = NULL;
1390         }
1391 
1392         switch (iscsilun->type) {
1393         case TYPE_DISK:
1394             task = iscsi_readcapacity16_sync(iscsilun->iscsi, iscsilun->lun);
1395             if (task != NULL && task->status == SCSI_STATUS_GOOD) {
1396                 rc16 = scsi_datain_unmarshall(task);
1397                 if (rc16 == NULL) {
1398                     error_setg(errp, "iSCSI: Failed to unmarshall readcapacity16 data.");
1399                 } else {
1400                     iscsilun->block_size = rc16->block_length;
1401                     iscsilun->num_blocks = rc16->returned_lba + 1;
1402                     iscsilun->lbpme = !!rc16->lbpme;
1403                     iscsilun->lbprz = !!rc16->lbprz;
1404                     iscsilun->use_16_for_rw = (rc16->returned_lba > 0xffffffff);
1405                 }
1406                 break;
1407             }
1408             if (task != NULL && task->status == SCSI_STATUS_CHECK_CONDITION
1409                 && task->sense.key == SCSI_SENSE_UNIT_ATTENTION) {
1410                 break;
1411             }
1412             /* Fall through and try READ CAPACITY(10) instead.  */
1413         case TYPE_ROM:
1414             task = iscsi_readcapacity10_sync(iscsilun->iscsi, iscsilun->lun, 0, 0);
1415             if (task != NULL && task->status == SCSI_STATUS_GOOD) {
1416                 rc10 = scsi_datain_unmarshall(task);
1417                 if (rc10 == NULL) {
1418                     error_setg(errp, "iSCSI: Failed to unmarshall readcapacity10 data.");
1419                 } else {
1420                     iscsilun->block_size = rc10->block_size;
1421                     if (rc10->lba == 0) {
1422                         /* blank disk loaded */
1423                         iscsilun->num_blocks = 0;
1424                     } else {
1425                         iscsilun->num_blocks = rc10->lba + 1;
1426                     }
1427                 }
1428             }
1429             break;
1430         default:
1431             return;
1432         }
1433     } while (task != NULL && task->status == SCSI_STATUS_CHECK_CONDITION
1434              && task->sense.key == SCSI_SENSE_UNIT_ATTENTION
1435              && retries-- > 0);
1436 
1437     if (task == NULL || task->status != SCSI_STATUS_GOOD) {
1438         error_setg(errp, "iSCSI: failed to send readcapacity10/16 command");
1439     } else if (!iscsilun->block_size ||
1440                iscsilun->block_size % BDRV_SECTOR_SIZE) {
1441         error_setg(errp, "iSCSI: the target returned an invalid "
1442                    "block size of %d.", iscsilun->block_size);
1443     }
1444     if (task) {
1445         scsi_free_scsi_task(task);
1446     }
1447 }
1448 
1449 static struct scsi_task *iscsi_do_inquiry(struct iscsi_context *iscsi, int lun,
1450                                           int evpd, int pc, void **inq, Error **errp)
1451 {
1452     int full_size;
1453     struct scsi_task *task = NULL;
1454     task = iscsi_inquiry_sync(iscsi, lun, evpd, pc, 64);
1455     if (task == NULL || task->status != SCSI_STATUS_GOOD) {
1456         goto fail;
1457     }
1458     full_size = scsi_datain_getfullsize(task);
1459     if (full_size > task->datain.size) {
1460         scsi_free_scsi_task(task);
1461 
1462         /* we need more data for the full list */
1463         task = iscsi_inquiry_sync(iscsi, lun, evpd, pc, full_size);
1464         if (task == NULL || task->status != SCSI_STATUS_GOOD) {
1465             goto fail;
1466         }
1467     }
1468 
1469     *inq = scsi_datain_unmarshall(task);
1470     if (*inq == NULL) {
1471         error_setg(errp, "iSCSI: failed to unmarshall inquiry datain blob");
1472         goto fail_with_err;
1473     }
1474 
1475     return task;
1476 
1477 fail:
1478     error_setg(errp, "iSCSI: Inquiry command failed : %s",
1479                iscsi_get_error(iscsi));
1480 fail_with_err:
1481     if (task != NULL) {
1482         scsi_free_scsi_task(task);
1483     }
1484     return NULL;
1485 }
1486 
1487 static void iscsi_detach_aio_context(BlockDriverState *bs)
1488 {
1489     IscsiLun *iscsilun = bs->opaque;
1490 
1491     aio_set_fd_handler(iscsilun->aio_context, iscsi_get_fd(iscsilun->iscsi),
1492                        false, NULL, NULL, NULL, NULL);
1493     iscsilun->events = 0;
1494 
1495     if (iscsilun->nop_timer) {
1496         timer_del(iscsilun->nop_timer);
1497         timer_free(iscsilun->nop_timer);
1498         iscsilun->nop_timer = NULL;
1499     }
1500     if (iscsilun->event_timer) {
1501         timer_del(iscsilun->event_timer);
1502         timer_free(iscsilun->event_timer);
1503         iscsilun->event_timer = NULL;
1504     }
1505 }
1506 
1507 static void iscsi_attach_aio_context(BlockDriverState *bs,
1508                                      AioContext *new_context)
1509 {
1510     IscsiLun *iscsilun = bs->opaque;
1511 
1512     iscsilun->aio_context = new_context;
1513     iscsi_set_events(iscsilun);
1514 
1515     /* Set up a timer for sending out iSCSI NOPs */
1516     iscsilun->nop_timer = aio_timer_new(iscsilun->aio_context,
1517                                         QEMU_CLOCK_REALTIME, SCALE_MS,
1518                                         iscsi_nop_timed_event, iscsilun);
1519     timer_mod(iscsilun->nop_timer,
1520               qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + NOP_INTERVAL);
1521 
1522     /* Set up a timer for periodic calls to iscsi_set_events and to
1523      * scan for command timeout */
1524     iscsilun->event_timer = aio_timer_new(iscsilun->aio_context,
1525                                           QEMU_CLOCK_REALTIME, SCALE_MS,
1526                                           iscsi_timed_check_events, iscsilun);
1527     timer_mod(iscsilun->event_timer,
1528               qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + EVENT_INTERVAL);
1529 }
1530 
1531 static void iscsi_modesense_sync(IscsiLun *iscsilun)
1532 {
1533     struct scsi_task *task;
1534     struct scsi_mode_sense *ms = NULL;
1535     iscsilun->write_protected = false;
1536     iscsilun->dpofua = false;
1537 
1538     task = iscsi_modesense6_sync(iscsilun->iscsi, iscsilun->lun,
1539                                  1, SCSI_MODESENSE_PC_CURRENT,
1540                                  0x3F, 0, 255);
1541     if (task == NULL) {
1542         error_report("iSCSI: Failed to send MODE_SENSE(6) command: %s",
1543                      iscsi_get_error(iscsilun->iscsi));
1544         goto out;
1545     }
1546 
1547     if (task->status != SCSI_STATUS_GOOD) {
1548         error_report("iSCSI: Failed MODE_SENSE(6), LUN assumed writable");
1549         goto out;
1550     }
1551     ms = scsi_datain_unmarshall(task);
1552     if (!ms) {
1553         error_report("iSCSI: Failed to unmarshall MODE_SENSE(6) data: %s",
1554                      iscsi_get_error(iscsilun->iscsi));
1555         goto out;
1556     }
1557     iscsilun->write_protected = ms->device_specific_parameter & 0x80;
1558     iscsilun->dpofua          = ms->device_specific_parameter & 0x10;
1559 
1560 out:
1561     if (task) {
1562         scsi_free_scsi_task(task);
1563     }
1564 }
1565 
1566 static void iscsi_parse_iscsi_option(const char *target, QDict *options)
1567 {
1568     QemuOptsList *list;
1569     QemuOpts *opts;
1570     const char *user, *password, *password_secret, *initiator_name,
1571                *header_digest, *timeout;
1572 
1573     list = qemu_find_opts("iscsi");
1574     if (!list) {
1575         return;
1576     }
1577 
1578     opts = qemu_opts_find(list, target);
1579     if (opts == NULL) {
1580         opts = QTAILQ_FIRST(&list->head);
1581         if (!opts) {
1582             return;
1583         }
1584     }
1585 
1586     user = qemu_opt_get(opts, "user");
1587     if (user) {
1588         qdict_set_default_str(options, "user", user);
1589     }
1590 
1591     password = qemu_opt_get(opts, "password");
1592     if (password) {
1593         qdict_set_default_str(options, "password", password);
1594     }
1595 
1596     password_secret = qemu_opt_get(opts, "password-secret");
1597     if (password_secret) {
1598         qdict_set_default_str(options, "password-secret", password_secret);
1599     }
1600 
1601     initiator_name = qemu_opt_get(opts, "initiator-name");
1602     if (initiator_name) {
1603         qdict_set_default_str(options, "initiator-name", initiator_name);
1604     }
1605 
1606     header_digest = qemu_opt_get(opts, "header-digest");
1607     if (header_digest) {
1608         /* -iscsi takes upper case values, but QAPI only supports lower case
1609          * enum constant names, so we have to convert here. */
1610         char *qapi_value = g_ascii_strdown(header_digest, -1);
1611         qdict_set_default_str(options, "header-digest", qapi_value);
1612         g_free(qapi_value);
1613     }
1614 
1615     timeout = qemu_opt_get(opts, "timeout");
1616     if (timeout) {
1617         qdict_set_default_str(options, "timeout", timeout);
1618     }
1619 }
1620 
1621 /*
1622  * We support iscsi url's on the form
1623  * iscsi://[<username>%<password>@]<host>[:<port>]/<targetname>/<lun>
1624  */
1625 static void iscsi_parse_filename(const char *filename, QDict *options,
1626                                  Error **errp)
1627 {
1628     struct iscsi_url *iscsi_url;
1629     const char *transport_name;
1630     char *lun_str;
1631 
1632     iscsi_url = iscsi_parse_full_url(NULL, filename);
1633     if (iscsi_url == NULL) {
1634         error_setg(errp, "Failed to parse URL : %s", filename);
1635         return;
1636     }
1637 
1638 #if LIBISCSI_API_VERSION >= (20160603)
1639     switch (iscsi_url->transport) {
1640     case TCP_TRANSPORT:
1641         transport_name = "tcp";
1642         break;
1643     case ISER_TRANSPORT:
1644         transport_name = "iser";
1645         break;
1646     default:
1647         error_setg(errp, "Unknown transport type (%d)",
1648                    iscsi_url->transport);
1649         return;
1650     }
1651 #else
1652     transport_name = "tcp";
1653 #endif
1654 
1655     qdict_set_default_str(options, "transport", transport_name);
1656     qdict_set_default_str(options, "portal", iscsi_url->portal);
1657     qdict_set_default_str(options, "target", iscsi_url->target);
1658 
1659     lun_str = g_strdup_printf("%d", iscsi_url->lun);
1660     qdict_set_default_str(options, "lun", lun_str);
1661     g_free(lun_str);
1662 
1663     /* User/password from -iscsi take precedence over those from the URL */
1664     iscsi_parse_iscsi_option(iscsi_url->target, options);
1665 
1666     if (iscsi_url->user[0] != '\0') {
1667         qdict_set_default_str(options, "user", iscsi_url->user);
1668         qdict_set_default_str(options, "password", iscsi_url->passwd);
1669     }
1670 
1671     iscsi_destroy_url(iscsi_url);
1672 }
1673 
1674 static QemuOptsList runtime_opts = {
1675     .name = "iscsi",
1676     .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
1677     .desc = {
1678         {
1679             .name = "transport",
1680             .type = QEMU_OPT_STRING,
1681         },
1682         {
1683             .name = "portal",
1684             .type = QEMU_OPT_STRING,
1685         },
1686         {
1687             .name = "target",
1688             .type = QEMU_OPT_STRING,
1689         },
1690         {
1691             .name = "user",
1692             .type = QEMU_OPT_STRING,
1693         },
1694         {
1695             .name = "password",
1696             .type = QEMU_OPT_STRING,
1697         },
1698         {
1699             .name = "password-secret",
1700             .type = QEMU_OPT_STRING,
1701         },
1702         {
1703             .name = "lun",
1704             .type = QEMU_OPT_NUMBER,
1705         },
1706         {
1707             .name = "initiator-name",
1708             .type = QEMU_OPT_STRING,
1709         },
1710         {
1711             .name = "header-digest",
1712             .type = QEMU_OPT_STRING,
1713         },
1714         {
1715             .name = "timeout",
1716             .type = QEMU_OPT_NUMBER,
1717         },
1718         { /* end of list */ }
1719     },
1720 };
1721 
1722 static void iscsi_save_designator(IscsiLun *lun,
1723                                   struct scsi_inquiry_device_identification *inq_di)
1724 {
1725     struct scsi_inquiry_device_designator *desig, *copy = NULL;
1726 
1727     for (desig = inq_di->designators; desig; desig = desig->next) {
1728         if (desig->association ||
1729             desig->designator_type > SCSI_DESIGNATOR_TYPE_NAA) {
1730             continue;
1731         }
1732         /* NAA works better than T10 vendor ID based designator. */
1733         if (!copy || copy->designator_type < desig->designator_type) {
1734             copy = desig;
1735         }
1736     }
1737     if (copy) {
1738         lun->dd = g_new(struct scsi_inquiry_device_designator, 1);
1739         *lun->dd = *copy;
1740         lun->dd->next = NULL;
1741         lun->dd->designator = g_malloc(copy->designator_length);
1742         memcpy(lun->dd->designator, copy->designator, copy->designator_length);
1743     }
1744 }
1745 
1746 static int iscsi_open(BlockDriverState *bs, QDict *options, int flags,
1747                       Error **errp)
1748 {
1749     IscsiLun *iscsilun = bs->opaque;
1750     struct iscsi_context *iscsi = NULL;
1751     struct scsi_task *task = NULL;
1752     struct scsi_inquiry_standard *inq = NULL;
1753     struct scsi_inquiry_supported_pages *inq_vpd;
1754     char *initiator_name = NULL;
1755     QemuOpts *opts;
1756     Error *local_err = NULL;
1757     const char *transport_name, *portal, *target;
1758 #if LIBISCSI_API_VERSION >= (20160603)
1759     enum iscsi_transport_type transport;
1760 #endif
1761     int i, ret = 0, timeout = 0, lun;
1762 
1763     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
1764     qemu_opts_absorb_qdict(opts, options, &local_err);
1765     if (local_err) {
1766         error_propagate(errp, local_err);
1767         ret = -EINVAL;
1768         goto out;
1769     }
1770 
1771     transport_name = qemu_opt_get(opts, "transport");
1772     portal = qemu_opt_get(opts, "portal");
1773     target = qemu_opt_get(opts, "target");
1774     lun = qemu_opt_get_number(opts, "lun", 0);
1775 
1776     if (!transport_name || !portal || !target) {
1777         error_setg(errp, "Need all of transport, portal and target options");
1778         ret = -EINVAL;
1779         goto out;
1780     }
1781 
1782     if (!strcmp(transport_name, "tcp")) {
1783 #if LIBISCSI_API_VERSION >= (20160603)
1784         transport = TCP_TRANSPORT;
1785     } else if (!strcmp(transport_name, "iser")) {
1786         transport = ISER_TRANSPORT;
1787 #else
1788         /* TCP is what older libiscsi versions always use */
1789 #endif
1790     } else {
1791         error_setg(errp, "Unknown transport: %s", transport_name);
1792         ret = -EINVAL;
1793         goto out;
1794     }
1795 
1796     memset(iscsilun, 0, sizeof(IscsiLun));
1797 
1798     initiator_name = get_initiator_name(opts);
1799 
1800     iscsi = iscsi_create_context(initiator_name);
1801     if (iscsi == NULL) {
1802         error_setg(errp, "iSCSI: Failed to create iSCSI context.");
1803         ret = -ENOMEM;
1804         goto out;
1805     }
1806 #if LIBISCSI_API_VERSION >= (20160603)
1807     if (iscsi_init_transport(iscsi, transport)) {
1808         error_setg(errp, ("Error initializing transport."));
1809         ret = -EINVAL;
1810         goto out;
1811     }
1812 #endif
1813     if (iscsi_set_targetname(iscsi, target)) {
1814         error_setg(errp, "iSCSI: Failed to set target name.");
1815         ret = -EINVAL;
1816         goto out;
1817     }
1818 
1819     /* check if we got CHAP username/password via the options */
1820     apply_chap(iscsi, opts, &local_err);
1821     if (local_err != NULL) {
1822         error_propagate(errp, local_err);
1823         ret = -EINVAL;
1824         goto out;
1825     }
1826 
1827     if (iscsi_set_session_type(iscsi, ISCSI_SESSION_NORMAL) != 0) {
1828         error_setg(errp, "iSCSI: Failed to set session type to normal.");
1829         ret = -EINVAL;
1830         goto out;
1831     }
1832 
1833     /* check if we got HEADER_DIGEST via the options */
1834     apply_header_digest(iscsi, opts, &local_err);
1835     if (local_err != NULL) {
1836         error_propagate(errp, local_err);
1837         ret = -EINVAL;
1838         goto out;
1839     }
1840 
1841     /* timeout handling is broken in libiscsi before 1.15.0 */
1842     timeout = qemu_opt_get_number(opts, "timeout", 0);
1843 #if LIBISCSI_API_VERSION >= 20150621
1844     iscsi_set_timeout(iscsi, timeout);
1845 #else
1846     if (timeout) {
1847         warn_report("iSCSI: ignoring timeout value for libiscsi <1.15.0");
1848     }
1849 #endif
1850 
1851     if (iscsi_full_connect_sync(iscsi, portal, lun) != 0) {
1852         error_setg(errp, "iSCSI: Failed to connect to LUN : %s",
1853             iscsi_get_error(iscsi));
1854         ret = -EINVAL;
1855         goto out;
1856     }
1857 
1858     iscsilun->iscsi = iscsi;
1859     iscsilun->aio_context = bdrv_get_aio_context(bs);
1860     iscsilun->lun = lun;
1861     iscsilun->has_write_same = true;
1862 
1863     task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 0, 0,
1864                             (void **) &inq, errp);
1865     if (task == NULL) {
1866         ret = -EINVAL;
1867         goto out;
1868     }
1869     iscsilun->type = inq->periperal_device_type;
1870     scsi_free_scsi_task(task);
1871     task = NULL;
1872 
1873     iscsi_modesense_sync(iscsilun);
1874     if (iscsilun->dpofua) {
1875         bs->supported_write_flags = BDRV_REQ_FUA;
1876     }
1877 
1878     /* Check the write protect flag of the LUN if we want to write */
1879     if (iscsilun->type == TYPE_DISK && (flags & BDRV_O_RDWR) &&
1880         iscsilun->write_protected) {
1881         error_setg(errp, "Cannot open a write protected LUN as read-write");
1882         ret = -EACCES;
1883         goto out;
1884     }
1885 
1886     iscsi_readcapacity_sync(iscsilun, &local_err);
1887     if (local_err != NULL) {
1888         error_propagate(errp, local_err);
1889         ret = -EINVAL;
1890         goto out;
1891     }
1892     bs->total_sectors = sector_lun2qemu(iscsilun->num_blocks, iscsilun);
1893 
1894     /* We don't have any emulation for devices other than disks and CD-ROMs, so
1895      * this must be sg ioctl compatible. We force it to be sg, otherwise qemu
1896      * will try to read from the device to guess the image format.
1897      */
1898     if (iscsilun->type != TYPE_DISK && iscsilun->type != TYPE_ROM) {
1899         bs->sg = true;
1900     }
1901 
1902     task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 1,
1903                             SCSI_INQUIRY_PAGECODE_SUPPORTED_VPD_PAGES,
1904                             (void **) &inq_vpd, errp);
1905     if (task == NULL) {
1906         ret = -EINVAL;
1907         goto out;
1908     }
1909     for (i = 0; i < inq_vpd->num_pages; i++) {
1910         struct scsi_task *inq_task;
1911         struct scsi_inquiry_logical_block_provisioning *inq_lbp;
1912         struct scsi_inquiry_block_limits *inq_bl;
1913         struct scsi_inquiry_device_identification *inq_di;
1914         switch (inq_vpd->pages[i]) {
1915         case SCSI_INQUIRY_PAGECODE_LOGICAL_BLOCK_PROVISIONING:
1916             inq_task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 1,
1917                                         SCSI_INQUIRY_PAGECODE_LOGICAL_BLOCK_PROVISIONING,
1918                                         (void **) &inq_lbp, errp);
1919             if (inq_task == NULL) {
1920                 ret = -EINVAL;
1921                 goto out;
1922             }
1923             memcpy(&iscsilun->lbp, inq_lbp,
1924                    sizeof(struct scsi_inquiry_logical_block_provisioning));
1925             scsi_free_scsi_task(inq_task);
1926             break;
1927         case SCSI_INQUIRY_PAGECODE_BLOCK_LIMITS:
1928             inq_task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 1,
1929                                     SCSI_INQUIRY_PAGECODE_BLOCK_LIMITS,
1930                                     (void **) &inq_bl, errp);
1931             if (inq_task == NULL) {
1932                 ret = -EINVAL;
1933                 goto out;
1934             }
1935             memcpy(&iscsilun->bl, inq_bl,
1936                    sizeof(struct scsi_inquiry_block_limits));
1937             scsi_free_scsi_task(inq_task);
1938             break;
1939         case SCSI_INQUIRY_PAGECODE_DEVICE_IDENTIFICATION:
1940             inq_task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 1,
1941                                     SCSI_INQUIRY_PAGECODE_DEVICE_IDENTIFICATION,
1942                                     (void **) &inq_di, errp);
1943             if (inq_task == NULL) {
1944                 ret = -EINVAL;
1945                 goto out;
1946             }
1947             iscsi_save_designator(iscsilun, inq_di);
1948             scsi_free_scsi_task(inq_task);
1949             break;
1950         default:
1951             break;
1952         }
1953     }
1954     scsi_free_scsi_task(task);
1955     task = NULL;
1956 
1957     qemu_mutex_init(&iscsilun->mutex);
1958     iscsi_attach_aio_context(bs, iscsilun->aio_context);
1959 
1960     /* Guess the internal cluster (page) size of the iscsi target by the means
1961      * of opt_unmap_gran. Transfer the unmap granularity only if it has a
1962      * reasonable size */
1963     if (iscsilun->bl.opt_unmap_gran * iscsilun->block_size >= 4 * 1024 &&
1964         iscsilun->bl.opt_unmap_gran * iscsilun->block_size <= 16 * 1024 * 1024) {
1965         iscsilun->cluster_size = iscsilun->bl.opt_unmap_gran *
1966             iscsilun->block_size;
1967         if (iscsilun->lbprz) {
1968             ret = iscsi_allocmap_init(iscsilun, bs->open_flags);
1969         }
1970     }
1971 
1972     if (iscsilun->lbprz && iscsilun->lbp.lbpws) {
1973         bs->supported_zero_flags = BDRV_REQ_MAY_UNMAP;
1974     }
1975 
1976 out:
1977     qemu_opts_del(opts);
1978     g_free(initiator_name);
1979     if (task != NULL) {
1980         scsi_free_scsi_task(task);
1981     }
1982 
1983     if (ret) {
1984         if (iscsi != NULL) {
1985             if (iscsi_is_logged_in(iscsi)) {
1986                 iscsi_logout_sync(iscsi);
1987             }
1988             iscsi_destroy_context(iscsi);
1989         }
1990         memset(iscsilun, 0, sizeof(IscsiLun));
1991     }
1992 
1993     return ret;
1994 }
1995 
1996 static void iscsi_close(BlockDriverState *bs)
1997 {
1998     IscsiLun *iscsilun = bs->opaque;
1999     struct iscsi_context *iscsi = iscsilun->iscsi;
2000 
2001     iscsi_detach_aio_context(bs);
2002     if (iscsi_is_logged_in(iscsi)) {
2003         iscsi_logout_sync(iscsi);
2004     }
2005     iscsi_destroy_context(iscsi);
2006     if (iscsilun->dd) {
2007         g_free(iscsilun->dd->designator);
2008         g_free(iscsilun->dd);
2009     }
2010     g_free(iscsilun->zeroblock);
2011     iscsi_allocmap_free(iscsilun);
2012     qemu_mutex_destroy(&iscsilun->mutex);
2013     memset(iscsilun, 0, sizeof(IscsiLun));
2014 }
2015 
2016 static void iscsi_refresh_limits(BlockDriverState *bs, Error **errp)
2017 {
2018     /* We don't actually refresh here, but just return data queried in
2019      * iscsi_open(): iscsi targets don't change their limits. */
2020 
2021     IscsiLun *iscsilun = bs->opaque;
2022     uint64_t max_xfer_len = iscsilun->use_16_for_rw ? 0xffffffff : 0xffff;
2023     unsigned int block_size = MAX(BDRV_SECTOR_SIZE, iscsilun->block_size);
2024 
2025     assert(iscsilun->block_size >= BDRV_SECTOR_SIZE || bs->sg);
2026 
2027     bs->bl.request_alignment = block_size;
2028 
2029     if (iscsilun->bl.max_xfer_len) {
2030         max_xfer_len = MIN(max_xfer_len, iscsilun->bl.max_xfer_len);
2031     }
2032 
2033     if (max_xfer_len * block_size < INT_MAX) {
2034         bs->bl.max_transfer = max_xfer_len * iscsilun->block_size;
2035     }
2036 
2037     if (iscsilun->lbp.lbpu) {
2038         if (iscsilun->bl.max_unmap < 0xffffffff / block_size) {
2039             bs->bl.max_pdiscard =
2040                 iscsilun->bl.max_unmap * iscsilun->block_size;
2041         }
2042         bs->bl.pdiscard_alignment =
2043             iscsilun->bl.opt_unmap_gran * iscsilun->block_size;
2044     } else {
2045         bs->bl.pdiscard_alignment = iscsilun->block_size;
2046     }
2047 
2048     if (iscsilun->bl.max_ws_len < 0xffffffff / block_size) {
2049         bs->bl.max_pwrite_zeroes =
2050             iscsilun->bl.max_ws_len * iscsilun->block_size;
2051     }
2052     if (iscsilun->lbp.lbpws) {
2053         bs->bl.pwrite_zeroes_alignment =
2054             iscsilun->bl.opt_unmap_gran * iscsilun->block_size;
2055     } else {
2056         bs->bl.pwrite_zeroes_alignment = iscsilun->block_size;
2057     }
2058     if (iscsilun->bl.opt_xfer_len &&
2059         iscsilun->bl.opt_xfer_len < INT_MAX / block_size) {
2060         bs->bl.opt_transfer = pow2floor(iscsilun->bl.opt_xfer_len *
2061                                         iscsilun->block_size);
2062     }
2063 }
2064 
2065 /* Note that this will not re-establish a connection with an iSCSI target - it
2066  * is effectively a NOP.  */
2067 static int iscsi_reopen_prepare(BDRVReopenState *state,
2068                                 BlockReopenQueue *queue, Error **errp)
2069 {
2070     IscsiLun *iscsilun = state->bs->opaque;
2071 
2072     if (state->flags & BDRV_O_RDWR && iscsilun->write_protected) {
2073         error_setg(errp, "Cannot open a write protected LUN as read-write");
2074         return -EACCES;
2075     }
2076     return 0;
2077 }
2078 
2079 static void iscsi_reopen_commit(BDRVReopenState *reopen_state)
2080 {
2081     IscsiLun *iscsilun = reopen_state->bs->opaque;
2082 
2083     /* the cache.direct status might have changed */
2084     if (iscsilun->allocmap != NULL) {
2085         iscsi_allocmap_init(iscsilun, reopen_state->flags);
2086     }
2087 }
2088 
2089 static int coroutine_fn iscsi_co_truncate(BlockDriverState *bs, int64_t offset,
2090                                           PreallocMode prealloc, Error **errp)
2091 {
2092     IscsiLun *iscsilun = bs->opaque;
2093     Error *local_err = NULL;
2094 
2095     if (prealloc != PREALLOC_MODE_OFF) {
2096         error_setg(errp, "Unsupported preallocation mode '%s'",
2097                    PreallocMode_str(prealloc));
2098         return -ENOTSUP;
2099     }
2100 
2101     if (iscsilun->type != TYPE_DISK) {
2102         error_setg(errp, "Cannot resize non-disk iSCSI devices");
2103         return -ENOTSUP;
2104     }
2105 
2106     iscsi_readcapacity_sync(iscsilun, &local_err);
2107     if (local_err != NULL) {
2108         error_propagate(errp, local_err);
2109         return -EIO;
2110     }
2111 
2112     if (offset > iscsi_getlength(bs)) {
2113         error_setg(errp, "Cannot grow iSCSI devices");
2114         return -EINVAL;
2115     }
2116 
2117     if (iscsilun->allocmap != NULL) {
2118         iscsi_allocmap_init(iscsilun, bs->open_flags);
2119     }
2120 
2121     return 0;
2122 }
2123 
2124 static int coroutine_fn iscsi_co_create_opts(const char *filename, QemuOpts *opts,
2125                                              Error **errp)
2126 {
2127     int ret = 0;
2128     int64_t total_size = 0;
2129     BlockDriverState *bs;
2130     IscsiLun *iscsilun = NULL;
2131     QDict *bs_options;
2132     Error *local_err = NULL;
2133 
2134     bs = bdrv_new();
2135 
2136     /* Read out options */
2137     total_size = DIV_ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
2138                               BDRV_SECTOR_SIZE);
2139     bs->opaque = g_new0(struct IscsiLun, 1);
2140     iscsilun = bs->opaque;
2141 
2142     bs_options = qdict_new();
2143     iscsi_parse_filename(filename, bs_options, &local_err);
2144     if (local_err) {
2145         error_propagate(errp, local_err);
2146         ret = -EINVAL;
2147     } else {
2148         ret = iscsi_open(bs, bs_options, 0, NULL);
2149     }
2150     qobject_unref(bs_options);
2151 
2152     if (ret != 0) {
2153         goto out;
2154     }
2155     iscsi_detach_aio_context(bs);
2156     if (iscsilun->type != TYPE_DISK) {
2157         ret = -ENODEV;
2158         goto out;
2159     }
2160     if (bs->total_sectors < total_size) {
2161         ret = -ENOSPC;
2162         goto out;
2163     }
2164 
2165     ret = 0;
2166 out:
2167     if (iscsilun->iscsi != NULL) {
2168         iscsi_destroy_context(iscsilun->iscsi);
2169     }
2170     g_free(bs->opaque);
2171     bs->opaque = NULL;
2172     bdrv_unref(bs);
2173     return ret;
2174 }
2175 
2176 static int iscsi_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
2177 {
2178     IscsiLun *iscsilun = bs->opaque;
2179     bdi->unallocated_blocks_are_zero = iscsilun->lbprz;
2180     bdi->cluster_size = iscsilun->cluster_size;
2181     return 0;
2182 }
2183 
2184 static void coroutine_fn iscsi_co_invalidate_cache(BlockDriverState *bs,
2185                                                    Error **errp)
2186 {
2187     IscsiLun *iscsilun = bs->opaque;
2188     iscsi_allocmap_invalidate(iscsilun);
2189 }
2190 
2191 static int coroutine_fn iscsi_co_copy_range_from(BlockDriverState *bs,
2192                                                  BdrvChild *src,
2193                                                  uint64_t src_offset,
2194                                                  BdrvChild *dst,
2195                                                  uint64_t dst_offset,
2196                                                  uint64_t bytes,
2197                                                  BdrvRequestFlags read_flags,
2198                                                  BdrvRequestFlags write_flags)
2199 {
2200     return bdrv_co_copy_range_to(src, src_offset, dst, dst_offset, bytes,
2201                                  read_flags, write_flags);
2202 }
2203 
2204 static struct scsi_task *iscsi_xcopy_task(int param_len)
2205 {
2206     struct scsi_task *task;
2207 
2208     task = g_new0(struct scsi_task, 1);
2209 
2210     task->cdb[0]     = EXTENDED_COPY;
2211     task->cdb[10]    = (param_len >> 24) & 0xFF;
2212     task->cdb[11]    = (param_len >> 16) & 0xFF;
2213     task->cdb[12]    = (param_len >> 8) & 0xFF;
2214     task->cdb[13]    = param_len & 0xFF;
2215     task->cdb_size   = 16;
2216     task->xfer_dir   = SCSI_XFER_WRITE;
2217     task->expxferlen = param_len;
2218 
2219     return task;
2220 }
2221 
2222 static void iscsi_populate_target_desc(unsigned char *desc, IscsiLun *lun)
2223 {
2224     struct scsi_inquiry_device_designator *dd = lun->dd;
2225 
2226     memset(desc, 0, 32);
2227     desc[0] = 0xE4; /* IDENT_DESCR_TGT_DESCR */
2228     desc[4] = dd->code_set;
2229     desc[5] = (dd->designator_type & 0xF)
2230         | ((dd->association & 3) << 4);
2231     desc[7] = dd->designator_length;
2232     memcpy(desc + 8, dd->designator, MIN(dd->designator_length, 20));
2233 
2234     desc[28] = 0;
2235     desc[29] = (lun->block_size >> 16) & 0xFF;
2236     desc[30] = (lun->block_size >> 8) & 0xFF;
2237     desc[31] = lun->block_size & 0xFF;
2238 }
2239 
2240 static void iscsi_xcopy_desc_hdr(uint8_t *hdr, int dc, int cat, int src_index,
2241                                  int dst_index)
2242 {
2243     hdr[0] = 0x02; /* BLK_TO_BLK_SEG_DESCR */
2244     hdr[1] = ((dc << 1) | cat) & 0xFF;
2245     hdr[2] = (XCOPY_BLK2BLK_SEG_DESC_SIZE >> 8) & 0xFF;
2246     /* don't account for the first 4 bytes in descriptor header*/
2247     hdr[3] = (XCOPY_BLK2BLK_SEG_DESC_SIZE - 4 /* SEG_DESC_SRC_INDEX_OFFSET */) & 0xFF;
2248     hdr[4] = (src_index >> 8) & 0xFF;
2249     hdr[5] = src_index & 0xFF;
2250     hdr[6] = (dst_index >> 8) & 0xFF;
2251     hdr[7] = dst_index & 0xFF;
2252 }
2253 
2254 static void iscsi_xcopy_populate_desc(uint8_t *desc, int dc, int cat,
2255                                       int src_index, int dst_index, int num_blks,
2256                                       uint64_t src_lba, uint64_t dst_lba)
2257 {
2258     iscsi_xcopy_desc_hdr(desc, dc, cat, src_index, dst_index);
2259 
2260     /* The caller should verify the request size */
2261     assert(num_blks < 65536);
2262     desc[10] = (num_blks >> 8) & 0xFF;
2263     desc[11] = num_blks & 0xFF;
2264     desc[12] = (src_lba >> 56) & 0xFF;
2265     desc[13] = (src_lba >> 48) & 0xFF;
2266     desc[14] = (src_lba >> 40) & 0xFF;
2267     desc[15] = (src_lba >> 32) & 0xFF;
2268     desc[16] = (src_lba >> 24) & 0xFF;
2269     desc[17] = (src_lba >> 16) & 0xFF;
2270     desc[18] = (src_lba >> 8) & 0xFF;
2271     desc[19] = src_lba & 0xFF;
2272     desc[20] = (dst_lba >> 56) & 0xFF;
2273     desc[21] = (dst_lba >> 48) & 0xFF;
2274     desc[22] = (dst_lba >> 40) & 0xFF;
2275     desc[23] = (dst_lba >> 32) & 0xFF;
2276     desc[24] = (dst_lba >> 24) & 0xFF;
2277     desc[25] = (dst_lba >> 16) & 0xFF;
2278     desc[26] = (dst_lba >> 8) & 0xFF;
2279     desc[27] = dst_lba & 0xFF;
2280 }
2281 
2282 static void iscsi_xcopy_populate_header(unsigned char *buf, int list_id, int str,
2283                                         int list_id_usage, int prio,
2284                                         int tgt_desc_len,
2285                                         int seg_desc_len, int inline_data_len)
2286 {
2287     buf[0] = list_id;
2288     buf[1] = ((str & 1) << 5) | ((list_id_usage & 3) << 3) | (prio & 7);
2289     buf[2] = (tgt_desc_len >> 8) & 0xFF;
2290     buf[3] = tgt_desc_len & 0xFF;
2291     buf[8] = (seg_desc_len >> 24) & 0xFF;
2292     buf[9] = (seg_desc_len >> 16) & 0xFF;
2293     buf[10] = (seg_desc_len >> 8) & 0xFF;
2294     buf[11] = seg_desc_len & 0xFF;
2295     buf[12] = (inline_data_len >> 24) & 0xFF;
2296     buf[13] = (inline_data_len >> 16) & 0xFF;
2297     buf[14] = (inline_data_len >> 8) & 0xFF;
2298     buf[15] = inline_data_len & 0xFF;
2299 }
2300 
2301 static void iscsi_xcopy_data(struct iscsi_data *data,
2302                              IscsiLun *src, int64_t src_lba,
2303                              IscsiLun *dst, int64_t dst_lba,
2304                              uint16_t num_blocks)
2305 {
2306     uint8_t *buf;
2307     const int src_offset = XCOPY_DESC_OFFSET;
2308     const int dst_offset = XCOPY_DESC_OFFSET + IDENT_DESCR_TGT_DESCR_SIZE;
2309     const int seg_offset = dst_offset + IDENT_DESCR_TGT_DESCR_SIZE;
2310 
2311     data->size = XCOPY_DESC_OFFSET +
2312                  IDENT_DESCR_TGT_DESCR_SIZE * 2 +
2313                  XCOPY_BLK2BLK_SEG_DESC_SIZE;
2314     data->data = g_malloc0(data->size);
2315     buf = data->data;
2316 
2317     /* Initialise the parameter list header */
2318     iscsi_xcopy_populate_header(buf, 1, 0, 2 /* LIST_ID_USAGE_DISCARD */,
2319                                 0, 2 * IDENT_DESCR_TGT_DESCR_SIZE,
2320                                 XCOPY_BLK2BLK_SEG_DESC_SIZE,
2321                                 0);
2322 
2323     /* Initialise CSCD list with one src + one dst descriptor */
2324     iscsi_populate_target_desc(&buf[src_offset], src);
2325     iscsi_populate_target_desc(&buf[dst_offset], dst);
2326 
2327     /* Initialise one segment descriptor */
2328     iscsi_xcopy_populate_desc(&buf[seg_offset], 0, 0, 0, 1, num_blocks,
2329                               src_lba, dst_lba);
2330 }
2331 
2332 static int coroutine_fn iscsi_co_copy_range_to(BlockDriverState *bs,
2333                                                BdrvChild *src,
2334                                                uint64_t src_offset,
2335                                                BdrvChild *dst,
2336                                                uint64_t dst_offset,
2337                                                uint64_t bytes,
2338                                                BdrvRequestFlags read_flags,
2339                                                BdrvRequestFlags write_flags)
2340 {
2341     IscsiLun *dst_lun = dst->bs->opaque;
2342     IscsiLun *src_lun;
2343     struct IscsiTask iscsi_task;
2344     struct iscsi_data data;
2345     int r = 0;
2346     int block_size;
2347 
2348     if (src->bs->drv->bdrv_co_copy_range_to != iscsi_co_copy_range_to) {
2349         return -ENOTSUP;
2350     }
2351     src_lun = src->bs->opaque;
2352 
2353     if (!src_lun->dd || !dst_lun->dd) {
2354         return -ENOTSUP;
2355     }
2356     if (!is_byte_request_lun_aligned(dst_offset, bytes, dst_lun)) {
2357         return -ENOTSUP;
2358     }
2359     if (!is_byte_request_lun_aligned(src_offset, bytes, src_lun)) {
2360         return -ENOTSUP;
2361     }
2362     if (dst_lun->block_size != src_lun->block_size ||
2363         !dst_lun->block_size) {
2364         return -ENOTSUP;
2365     }
2366 
2367     block_size = dst_lun->block_size;
2368     if (bytes / block_size > 65535) {
2369         return -ENOTSUP;
2370     }
2371 
2372     iscsi_xcopy_data(&data,
2373                      src_lun, src_offset / block_size,
2374                      dst_lun, dst_offset / block_size,
2375                      bytes / block_size);
2376 
2377     iscsi_co_init_iscsitask(dst_lun, &iscsi_task);
2378 
2379     qemu_mutex_lock(&dst_lun->mutex);
2380     iscsi_task.task = iscsi_xcopy_task(data.size);
2381 retry:
2382     if (iscsi_scsi_command_async(dst_lun->iscsi, dst_lun->lun,
2383                                  iscsi_task.task, iscsi_co_generic_cb,
2384                                  &data,
2385                                  &iscsi_task) != 0) {
2386         r = -EIO;
2387         goto out_unlock;
2388     }
2389 
2390     iscsi_co_wait_for_task(&iscsi_task, dst_lun);
2391 
2392     if (iscsi_task.do_retry) {
2393         iscsi_task.complete = 0;
2394         goto retry;
2395     }
2396 
2397     if (iscsi_task.status != SCSI_STATUS_GOOD) {
2398         r = iscsi_task.err_code;
2399         goto out_unlock;
2400     }
2401 
2402 out_unlock:
2403 
2404     trace_iscsi_xcopy(src_lun, src_offset, dst_lun, dst_offset, bytes, r);
2405     g_free(iscsi_task.task);
2406     qemu_mutex_unlock(&dst_lun->mutex);
2407     g_free(iscsi_task.err_str);
2408     return r;
2409 }
2410 
2411 static QemuOptsList iscsi_create_opts = {
2412     .name = "iscsi-create-opts",
2413     .head = QTAILQ_HEAD_INITIALIZER(iscsi_create_opts.head),
2414     .desc = {
2415         {
2416             .name = BLOCK_OPT_SIZE,
2417             .type = QEMU_OPT_SIZE,
2418             .help = "Virtual disk size"
2419         },
2420         { /* end of list */ }
2421     }
2422 };
2423 
2424 static BlockDriver bdrv_iscsi = {
2425     .format_name     = "iscsi",
2426     .protocol_name   = "iscsi",
2427 
2428     .instance_size          = sizeof(IscsiLun),
2429     .bdrv_parse_filename    = iscsi_parse_filename,
2430     .bdrv_file_open         = iscsi_open,
2431     .bdrv_close             = iscsi_close,
2432     .bdrv_co_create_opts    = iscsi_co_create_opts,
2433     .create_opts            = &iscsi_create_opts,
2434     .bdrv_reopen_prepare    = iscsi_reopen_prepare,
2435     .bdrv_reopen_commit     = iscsi_reopen_commit,
2436     .bdrv_co_invalidate_cache = iscsi_co_invalidate_cache,
2437 
2438     .bdrv_getlength  = iscsi_getlength,
2439     .bdrv_get_info   = iscsi_get_info,
2440     .bdrv_co_truncate    = iscsi_co_truncate,
2441     .bdrv_refresh_limits = iscsi_refresh_limits,
2442 
2443     .bdrv_co_block_status  = iscsi_co_block_status,
2444     .bdrv_co_pdiscard      = iscsi_co_pdiscard,
2445     .bdrv_co_copy_range_from = iscsi_co_copy_range_from,
2446     .bdrv_co_copy_range_to  = iscsi_co_copy_range_to,
2447     .bdrv_co_pwrite_zeroes = iscsi_co_pwrite_zeroes,
2448     .bdrv_co_readv         = iscsi_co_readv,
2449     .bdrv_co_writev        = iscsi_co_writev,
2450     .bdrv_co_flush_to_disk = iscsi_co_flush,
2451 
2452 #ifdef __linux__
2453     .bdrv_aio_ioctl   = iscsi_aio_ioctl,
2454 #endif
2455 
2456     .bdrv_detach_aio_context = iscsi_detach_aio_context,
2457     .bdrv_attach_aio_context = iscsi_attach_aio_context,
2458 };
2459 
2460 #if LIBISCSI_API_VERSION >= (20160603)
2461 static BlockDriver bdrv_iser = {
2462     .format_name     = "iser",
2463     .protocol_name   = "iser",
2464 
2465     .instance_size          = sizeof(IscsiLun),
2466     .bdrv_parse_filename    = iscsi_parse_filename,
2467     .bdrv_file_open         = iscsi_open,
2468     .bdrv_close             = iscsi_close,
2469     .bdrv_co_create_opts    = iscsi_co_create_opts,
2470     .create_opts            = &iscsi_create_opts,
2471     .bdrv_reopen_prepare    = iscsi_reopen_prepare,
2472     .bdrv_reopen_commit     = iscsi_reopen_commit,
2473     .bdrv_co_invalidate_cache  = iscsi_co_invalidate_cache,
2474 
2475     .bdrv_getlength  = iscsi_getlength,
2476     .bdrv_get_info   = iscsi_get_info,
2477     .bdrv_co_truncate    = iscsi_co_truncate,
2478     .bdrv_refresh_limits = iscsi_refresh_limits,
2479 
2480     .bdrv_co_block_status  = iscsi_co_block_status,
2481     .bdrv_co_pdiscard      = iscsi_co_pdiscard,
2482     .bdrv_co_copy_range_from = iscsi_co_copy_range_from,
2483     .bdrv_co_copy_range_to  = iscsi_co_copy_range_to,
2484     .bdrv_co_pwrite_zeroes = iscsi_co_pwrite_zeroes,
2485     .bdrv_co_readv         = iscsi_co_readv,
2486     .bdrv_co_writev        = iscsi_co_writev,
2487     .bdrv_co_flush_to_disk = iscsi_co_flush,
2488 
2489 #ifdef __linux__
2490     .bdrv_aio_ioctl   = iscsi_aio_ioctl,
2491 #endif
2492 
2493     .bdrv_detach_aio_context = iscsi_detach_aio_context,
2494     .bdrv_attach_aio_context = iscsi_attach_aio_context,
2495 };
2496 #endif
2497 
2498 static void iscsi_block_init(void)
2499 {
2500     bdrv_register(&bdrv_iscsi);
2501 #if LIBISCSI_API_VERSION >= (20160603)
2502     bdrv_register(&bdrv_iser);
2503 #endif
2504 }
2505 
2506 block_init(iscsi_block_init);
2507