xref: /openbmc/qemu/block/iscsi.c (revision 52c95cae)
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 "scsi/constants.h"
37 #include "qemu/iov.h"
38 #include "qemu/option.h"
39 #include "qemu/uuid.h"
40 #include "qapi/error.h"
41 #include "qapi/qapi-commands-misc.h"
42 #include "qapi/qmp/qdict.h"
43 #include "qapi/qmp/qstring.h"
44 #include "crypto/secret.h"
45 #include "scsi/utils.h"
46 
47 /* Conflict between scsi/utils.h and libiscsi! :( */
48 #define SCSI_XFER_NONE ISCSI_XFER_NONE
49 #include <iscsi/iscsi.h>
50 #include <iscsi/scsi-lowlevel.h>
51 #undef SCSI_XFER_NONE
52 QEMU_BUILD_BUG_ON((int)SCSI_XFER_NONE != (int)ISCSI_XFER_NONE);
53 
54 #ifdef __linux__
55 #include <scsi/sg.h>
56 #endif
57 
58 typedef struct IscsiLun {
59     struct iscsi_context *iscsi;
60     AioContext *aio_context;
61     int lun;
62     enum scsi_inquiry_peripheral_device_type type;
63     int block_size;
64     uint64_t num_blocks;
65     int events;
66     QEMUTimer *nop_timer;
67     QEMUTimer *event_timer;
68     QemuMutex mutex;
69     struct scsi_inquiry_logical_block_provisioning lbp;
70     struct scsi_inquiry_block_limits bl;
71     unsigned char *zeroblock;
72     /* The allocmap tracks which clusters (pages) on the iSCSI target are
73      * allocated and which are not. In case a target returns zeros for
74      * unallocated pages (iscsilun->lprz) we can directly return zeros instead
75      * of reading zeros over the wire if a read request falls within an
76      * unallocated block. As there are 3 possible states we need 2 bitmaps to
77      * track. allocmap_valid keeps track if QEMU's information about a page is
78      * valid. allocmap tracks if a page is allocated or not. In case QEMU has no
79      * valid information about a page the corresponding allocmap entry should be
80      * switched to unallocated as well to force a new lookup of the allocation
81      * status as lookups are generally skipped if a page is suspect to be
82      * allocated. If a iSCSI target is opened with cache.direct = on the
83      * allocmap_valid does not exist turning all cached information invalid so
84      * that a fresh lookup is made for any page even if allocmap entry returns
85      * it's unallocated. */
86     unsigned long *allocmap;
87     unsigned long *allocmap_valid;
88     long allocmap_size;
89     int cluster_size;
90     bool use_16_for_rw;
91     bool write_protected;
92     bool lbpme;
93     bool lbprz;
94     bool dpofua;
95     bool has_write_same;
96     bool request_timed_out;
97 } IscsiLun;
98 
99 typedef struct IscsiTask {
100     int status;
101     int complete;
102     int retries;
103     int do_retry;
104     struct scsi_task *task;
105     Coroutine *co;
106     IscsiLun *iscsilun;
107     QEMUTimer retry_timer;
108     int err_code;
109     char *err_str;
110 } IscsiTask;
111 
112 typedef struct IscsiAIOCB {
113     BlockAIOCB common;
114     QEMUBH *bh;
115     IscsiLun *iscsilun;
116     struct scsi_task *task;
117     uint8_t *buf;
118     int status;
119     int64_t sector_num;
120     int nb_sectors;
121     int ret;
122 #ifdef __linux__
123     sg_io_hdr_t *ioh;
124 #endif
125 } IscsiAIOCB;
126 
127 /* libiscsi uses time_t so its enough to process events every second */
128 #define EVENT_INTERVAL 1000
129 #define NOP_INTERVAL 5000
130 #define MAX_NOP_FAILURES 3
131 #define ISCSI_CMD_RETRIES ARRAY_SIZE(iscsi_retry_times)
132 static const unsigned iscsi_retry_times[] = {8, 32, 128, 512, 2048, 8192, 32768};
133 
134 /* this threshold is a trade-off knob to choose between
135  * the potential additional overhead of an extra GET_LBA_STATUS request
136  * vs. unnecessarily reading a lot of zero sectors over the wire.
137  * If a read request is greater or equal than ISCSI_CHECKALLOC_THRES
138  * sectors we check the allocation status of the area covered by the
139  * request first if the allocationmap indicates that the area might be
140  * unallocated. */
141 #define ISCSI_CHECKALLOC_THRES 64
142 
143 static void
144 iscsi_bh_cb(void *p)
145 {
146     IscsiAIOCB *acb = p;
147 
148     qemu_bh_delete(acb->bh);
149 
150     g_free(acb->buf);
151     acb->buf = NULL;
152 
153     acb->common.cb(acb->common.opaque, acb->status);
154 
155     if (acb->task != NULL) {
156         scsi_free_scsi_task(acb->task);
157         acb->task = NULL;
158     }
159 
160     qemu_aio_unref(acb);
161 }
162 
163 static void
164 iscsi_schedule_bh(IscsiAIOCB *acb)
165 {
166     if (acb->bh) {
167         return;
168     }
169     acb->bh = aio_bh_new(acb->iscsilun->aio_context, iscsi_bh_cb, acb);
170     qemu_bh_schedule(acb->bh);
171 }
172 
173 static void iscsi_co_generic_bh_cb(void *opaque)
174 {
175     struct IscsiTask *iTask = opaque;
176 
177     iTask->complete = 1;
178     aio_co_wake(iTask->co);
179 }
180 
181 static void iscsi_retry_timer_expired(void *opaque)
182 {
183     struct IscsiTask *iTask = opaque;
184     iTask->complete = 1;
185     if (iTask->co) {
186         aio_co_wake(iTask->co);
187     }
188 }
189 
190 static inline unsigned exp_random(double mean)
191 {
192     return -mean * log((double)rand() / RAND_MAX);
193 }
194 
195 /* SCSI_SENSE_ASCQ_INVALID_FIELD_IN_PARAMETER_LIST was introduced in
196  * libiscsi 1.10.0, together with other constants we need.  Use it as
197  * a hint that we have to define them ourselves if needed, to keep the
198  * minimum required libiscsi version at 1.9.0.  We use an ASCQ macro for
199  * the test because SCSI_STATUS_* is an enum.
200  *
201  * To guard against future changes where SCSI_SENSE_ASCQ_* also becomes
202  * an enum, check against the LIBISCSI_API_VERSION macro, which was
203  * introduced in 1.11.0.  If it is present, there is no need to define
204  * anything.
205  */
206 #if !defined(SCSI_SENSE_ASCQ_INVALID_FIELD_IN_PARAMETER_LIST) && \
207     !defined(LIBISCSI_API_VERSION)
208 #define SCSI_STATUS_TASK_SET_FULL                          0x28
209 #define SCSI_STATUS_TIMEOUT                                0x0f000002
210 #define SCSI_SENSE_ASCQ_INVALID_FIELD_IN_PARAMETER_LIST    0x2600
211 #define SCSI_SENSE_ASCQ_PARAMETER_LIST_LENGTH_ERROR        0x1a00
212 #endif
213 
214 #ifndef LIBISCSI_API_VERSION
215 #define LIBISCSI_API_VERSION 20130701
216 #endif
217 
218 static int iscsi_translate_sense(struct scsi_sense *sense)
219 {
220     return - scsi_sense_to_errno(sense->key,
221                                  (sense->ascq & 0xFF00) >> 8,
222                                  sense->ascq & 0xFF);
223 }
224 
225 /* Called (via iscsi_service) with QemuMutex held.  */
226 static void
227 iscsi_co_generic_cb(struct iscsi_context *iscsi, int status,
228                         void *command_data, void *opaque)
229 {
230     struct IscsiTask *iTask = opaque;
231     struct scsi_task *task = command_data;
232 
233     iTask->status = status;
234     iTask->do_retry = 0;
235     iTask->task = task;
236 
237     if (status != SCSI_STATUS_GOOD) {
238         if (iTask->retries++ < ISCSI_CMD_RETRIES) {
239             if (status == SCSI_STATUS_CHECK_CONDITION
240                 && task->sense.key == SCSI_SENSE_UNIT_ATTENTION) {
241                 error_report("iSCSI CheckCondition: %s",
242                              iscsi_get_error(iscsi));
243                 iTask->do_retry = 1;
244                 goto out;
245             }
246             if (status == SCSI_STATUS_BUSY ||
247                 status == SCSI_STATUS_TIMEOUT ||
248                 status == SCSI_STATUS_TASK_SET_FULL) {
249                 unsigned retry_time =
250                     exp_random(iscsi_retry_times[iTask->retries - 1]);
251                 if (status == SCSI_STATUS_TIMEOUT) {
252                     /* make sure the request is rescheduled AFTER the
253                      * reconnect is initiated */
254                     retry_time = EVENT_INTERVAL * 2;
255                     iTask->iscsilun->request_timed_out = true;
256                 }
257                 error_report("iSCSI Busy/TaskSetFull/TimeOut"
258                              " (retry #%u in %u ms): %s",
259                              iTask->retries, retry_time,
260                              iscsi_get_error(iscsi));
261                 aio_timer_init(iTask->iscsilun->aio_context,
262                                &iTask->retry_timer, QEMU_CLOCK_REALTIME,
263                                SCALE_MS, iscsi_retry_timer_expired, iTask);
264                 timer_mod(&iTask->retry_timer,
265                           qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + retry_time);
266                 iTask->do_retry = 1;
267                 return;
268             }
269         }
270         iTask->err_code = iscsi_translate_sense(&task->sense);
271         iTask->err_str = g_strdup(iscsi_get_error(iscsi));
272     }
273 
274 out:
275     if (iTask->co) {
276         aio_bh_schedule_oneshot(iTask->iscsilun->aio_context,
277                                  iscsi_co_generic_bh_cb, iTask);
278     } else {
279         iTask->complete = 1;
280     }
281 }
282 
283 static void iscsi_co_init_iscsitask(IscsiLun *iscsilun, struct IscsiTask *iTask)
284 {
285     *iTask = (struct IscsiTask) {
286         .co         = qemu_coroutine_self(),
287         .iscsilun   = iscsilun,
288     };
289 }
290 
291 static void
292 iscsi_abort_task_cb(struct iscsi_context *iscsi, int status, void *command_data,
293                     void *private_data)
294 {
295     IscsiAIOCB *acb = private_data;
296 
297     acb->status = -ECANCELED;
298     iscsi_schedule_bh(acb);
299 }
300 
301 static void
302 iscsi_aio_cancel(BlockAIOCB *blockacb)
303 {
304     IscsiAIOCB *acb = (IscsiAIOCB *)blockacb;
305     IscsiLun *iscsilun = acb->iscsilun;
306 
307     if (acb->status != -EINPROGRESS) {
308         return;
309     }
310 
311     /* send a task mgmt call to the target to cancel the task on the target */
312     iscsi_task_mgmt_abort_task_async(iscsilun->iscsi, acb->task,
313                                      iscsi_abort_task_cb, acb);
314 
315 }
316 
317 static const AIOCBInfo iscsi_aiocb_info = {
318     .aiocb_size         = sizeof(IscsiAIOCB),
319     .cancel_async       = iscsi_aio_cancel,
320 };
321 
322 
323 static void iscsi_process_read(void *arg);
324 static void iscsi_process_write(void *arg);
325 
326 /* Called with QemuMutex held.  */
327 static void
328 iscsi_set_events(IscsiLun *iscsilun)
329 {
330     struct iscsi_context *iscsi = iscsilun->iscsi;
331     int ev = iscsi_which_events(iscsi);
332 
333     if (ev != iscsilun->events) {
334         aio_set_fd_handler(iscsilun->aio_context, iscsi_get_fd(iscsi),
335                            false,
336                            (ev & POLLIN) ? iscsi_process_read : NULL,
337                            (ev & POLLOUT) ? iscsi_process_write : NULL,
338                            NULL,
339                            iscsilun);
340         iscsilun->events = ev;
341     }
342 }
343 
344 static void iscsi_timed_check_events(void *opaque)
345 {
346     IscsiLun *iscsilun = opaque;
347 
348     /* check for timed out requests */
349     iscsi_service(iscsilun->iscsi, 0);
350 
351     if (iscsilun->request_timed_out) {
352         iscsilun->request_timed_out = false;
353         iscsi_reconnect(iscsilun->iscsi);
354     }
355 
356     /* newer versions of libiscsi may return zero events. Ensure we are able
357      * to return to service once this situation changes. */
358     iscsi_set_events(iscsilun);
359 
360     timer_mod(iscsilun->event_timer,
361               qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + EVENT_INTERVAL);
362 }
363 
364 static void
365 iscsi_process_read(void *arg)
366 {
367     IscsiLun *iscsilun = arg;
368     struct iscsi_context *iscsi = iscsilun->iscsi;
369 
370     qemu_mutex_lock(&iscsilun->mutex);
371     iscsi_service(iscsi, POLLIN);
372     iscsi_set_events(iscsilun);
373     qemu_mutex_unlock(&iscsilun->mutex);
374 }
375 
376 static void
377 iscsi_process_write(void *arg)
378 {
379     IscsiLun *iscsilun = arg;
380     struct iscsi_context *iscsi = iscsilun->iscsi;
381 
382     qemu_mutex_lock(&iscsilun->mutex);
383     iscsi_service(iscsi, POLLOUT);
384     iscsi_set_events(iscsilun);
385     qemu_mutex_unlock(&iscsilun->mutex);
386 }
387 
388 static int64_t sector_lun2qemu(int64_t sector, IscsiLun *iscsilun)
389 {
390     return sector * iscsilun->block_size / BDRV_SECTOR_SIZE;
391 }
392 
393 static int64_t sector_qemu2lun(int64_t sector, IscsiLun *iscsilun)
394 {
395     return sector * BDRV_SECTOR_SIZE / iscsilun->block_size;
396 }
397 
398 static bool is_byte_request_lun_aligned(int64_t offset, int count,
399                                         IscsiLun *iscsilun)
400 {
401     if (offset % iscsilun->block_size || count % iscsilun->block_size) {
402         error_report("iSCSI misaligned request: "
403                      "iscsilun->block_size %u, offset %" PRIi64
404                      ", count %d",
405                      iscsilun->block_size, offset, count);
406         return false;
407     }
408     return true;
409 }
410 
411 static bool is_sector_request_lun_aligned(int64_t sector_num, int nb_sectors,
412                                           IscsiLun *iscsilun)
413 {
414     assert(nb_sectors <= BDRV_REQUEST_MAX_SECTORS);
415     return is_byte_request_lun_aligned(sector_num << BDRV_SECTOR_BITS,
416                                        nb_sectors << BDRV_SECTOR_BITS,
417                                        iscsilun);
418 }
419 
420 static void iscsi_allocmap_free(IscsiLun *iscsilun)
421 {
422     g_free(iscsilun->allocmap);
423     g_free(iscsilun->allocmap_valid);
424     iscsilun->allocmap = NULL;
425     iscsilun->allocmap_valid = NULL;
426 }
427 
428 
429 static int iscsi_allocmap_init(IscsiLun *iscsilun, int open_flags)
430 {
431     iscsi_allocmap_free(iscsilun);
432 
433     assert(iscsilun->cluster_size);
434     iscsilun->allocmap_size =
435         DIV_ROUND_UP(iscsilun->num_blocks * iscsilun->block_size,
436                      iscsilun->cluster_size);
437 
438     iscsilun->allocmap = bitmap_try_new(iscsilun->allocmap_size);
439     if (!iscsilun->allocmap) {
440         return -ENOMEM;
441     }
442 
443     if (open_flags & BDRV_O_NOCACHE) {
444         /* when cache.direct = on all allocmap entries are
445          * treated as invalid to force a relookup of the block
446          * status on every read request */
447         return 0;
448     }
449 
450     iscsilun->allocmap_valid = bitmap_try_new(iscsilun->allocmap_size);
451     if (!iscsilun->allocmap_valid) {
452         /* if we are under memory pressure free the allocmap as well */
453         iscsi_allocmap_free(iscsilun);
454         return -ENOMEM;
455     }
456 
457     return 0;
458 }
459 
460 static void
461 iscsi_allocmap_update(IscsiLun *iscsilun, int64_t offset,
462                       int64_t bytes, bool allocated, bool valid)
463 {
464     int64_t cl_num_expanded, nb_cls_expanded, cl_num_shrunk, nb_cls_shrunk;
465 
466     if (iscsilun->allocmap == NULL) {
467         return;
468     }
469     /* expand to entirely contain all affected clusters */
470     assert(iscsilun->cluster_size);
471     cl_num_expanded = offset / iscsilun->cluster_size;
472     nb_cls_expanded = DIV_ROUND_UP(offset + bytes,
473                                    iscsilun->cluster_size) - cl_num_expanded;
474     /* shrink to touch only completely contained clusters */
475     cl_num_shrunk = DIV_ROUND_UP(offset, iscsilun->cluster_size);
476     nb_cls_shrunk = (offset + bytes) / iscsilun->cluster_size - cl_num_shrunk;
477     if (allocated) {
478         bitmap_set(iscsilun->allocmap, cl_num_expanded, nb_cls_expanded);
479     } else {
480         if (nb_cls_shrunk > 0) {
481             bitmap_clear(iscsilun->allocmap, cl_num_shrunk, nb_cls_shrunk);
482         }
483     }
484 
485     if (iscsilun->allocmap_valid == NULL) {
486         return;
487     }
488     if (valid) {
489         if (nb_cls_shrunk > 0) {
490             bitmap_set(iscsilun->allocmap_valid, cl_num_shrunk, nb_cls_shrunk);
491         }
492     } else {
493         bitmap_clear(iscsilun->allocmap_valid, cl_num_expanded,
494                      nb_cls_expanded);
495     }
496 }
497 
498 static void
499 iscsi_allocmap_set_allocated(IscsiLun *iscsilun, int64_t offset,
500                              int64_t bytes)
501 {
502     iscsi_allocmap_update(iscsilun, offset, bytes, true, true);
503 }
504 
505 static void
506 iscsi_allocmap_set_unallocated(IscsiLun *iscsilun, int64_t offset,
507                                int64_t bytes)
508 {
509     /* Note: if cache.direct=on the fifth argument to iscsi_allocmap_update
510      * is ignored, so this will in effect be an iscsi_allocmap_set_invalid.
511      */
512     iscsi_allocmap_update(iscsilun, offset, bytes, false, true);
513 }
514 
515 static void iscsi_allocmap_set_invalid(IscsiLun *iscsilun, int64_t offset,
516                                        int64_t bytes)
517 {
518     iscsi_allocmap_update(iscsilun, offset, bytes, false, false);
519 }
520 
521 static void iscsi_allocmap_invalidate(IscsiLun *iscsilun)
522 {
523     if (iscsilun->allocmap) {
524         bitmap_zero(iscsilun->allocmap, iscsilun->allocmap_size);
525     }
526     if (iscsilun->allocmap_valid) {
527         bitmap_zero(iscsilun->allocmap_valid, iscsilun->allocmap_size);
528     }
529 }
530 
531 static inline bool
532 iscsi_allocmap_is_allocated(IscsiLun *iscsilun, int64_t offset,
533                             int64_t bytes)
534 {
535     unsigned long size;
536     if (iscsilun->allocmap == NULL) {
537         return true;
538     }
539     assert(iscsilun->cluster_size);
540     size = DIV_ROUND_UP(offset + bytes, iscsilun->cluster_size);
541     return !(find_next_bit(iscsilun->allocmap, size,
542                            offset / iscsilun->cluster_size) == size);
543 }
544 
545 static inline bool iscsi_allocmap_is_valid(IscsiLun *iscsilun,
546                                            int64_t offset, int64_t bytes)
547 {
548     unsigned long size;
549     if (iscsilun->allocmap_valid == NULL) {
550         return false;
551     }
552     assert(iscsilun->cluster_size);
553     size = DIV_ROUND_UP(offset + bytes, iscsilun->cluster_size);
554     return (find_next_zero_bit(iscsilun->allocmap_valid, size,
555                                offset / iscsilun->cluster_size) == size);
556 }
557 
558 static int coroutine_fn
559 iscsi_co_writev_flags(BlockDriverState *bs, int64_t sector_num, int nb_sectors,
560                       QEMUIOVector *iov, int flags)
561 {
562     IscsiLun *iscsilun = bs->opaque;
563     struct IscsiTask iTask;
564     uint64_t lba;
565     uint32_t num_sectors;
566     bool fua = flags & BDRV_REQ_FUA;
567     int r = 0;
568 
569     if (fua) {
570         assert(iscsilun->dpofua);
571     }
572     if (!is_sector_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
573         return -EINVAL;
574     }
575 
576     if (bs->bl.max_transfer) {
577         assert(nb_sectors << BDRV_SECTOR_BITS <= bs->bl.max_transfer);
578     }
579 
580     lba = sector_qemu2lun(sector_num, iscsilun);
581     num_sectors = sector_qemu2lun(nb_sectors, iscsilun);
582     iscsi_co_init_iscsitask(iscsilun, &iTask);
583     qemu_mutex_lock(&iscsilun->mutex);
584 retry:
585     if (iscsilun->use_16_for_rw) {
586 #if LIBISCSI_API_VERSION >= (20160603)
587         iTask.task = iscsi_write16_iov_task(iscsilun->iscsi, iscsilun->lun, lba,
588                                             NULL, num_sectors * iscsilun->block_size,
589                                             iscsilun->block_size, 0, 0, fua, 0, 0,
590                                             iscsi_co_generic_cb, &iTask,
591                                             (struct scsi_iovec *)iov->iov, iov->niov);
592     } else {
593         iTask.task = iscsi_write10_iov_task(iscsilun->iscsi, iscsilun->lun, lba,
594                                             NULL, num_sectors * iscsilun->block_size,
595                                             iscsilun->block_size, 0, 0, fua, 0, 0,
596                                             iscsi_co_generic_cb, &iTask,
597                                             (struct scsi_iovec *)iov->iov, iov->niov);
598     }
599 #else
600         iTask.task = iscsi_write16_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     } else {
605         iTask.task = iscsi_write10_task(iscsilun->iscsi, iscsilun->lun, lba,
606                                         NULL, num_sectors * iscsilun->block_size,
607                                         iscsilun->block_size, 0, 0, fua, 0, 0,
608                                         iscsi_co_generic_cb, &iTask);
609     }
610 #endif
611     if (iTask.task == NULL) {
612         qemu_mutex_unlock(&iscsilun->mutex);
613         return -ENOMEM;
614     }
615 #if LIBISCSI_API_VERSION < (20160603)
616     scsi_task_set_iov_out(iTask.task, (struct scsi_iovec *) iov->iov,
617                           iov->niov);
618 #endif
619     while (!iTask.complete) {
620         iscsi_set_events(iscsilun);
621         qemu_mutex_unlock(&iscsilun->mutex);
622         qemu_coroutine_yield();
623         qemu_mutex_lock(&iscsilun->mutex);
624     }
625 
626     if (iTask.task != NULL) {
627         scsi_free_scsi_task(iTask.task);
628         iTask.task = NULL;
629     }
630 
631     if (iTask.do_retry) {
632         iTask.complete = 0;
633         goto retry;
634     }
635 
636     if (iTask.status != SCSI_STATUS_GOOD) {
637         iscsi_allocmap_set_invalid(iscsilun, sector_num * BDRV_SECTOR_SIZE,
638                                    nb_sectors * BDRV_SECTOR_SIZE);
639         error_report("iSCSI WRITE10/16 failed at lba %" PRIu64 ": %s", lba,
640                      iTask.err_str);
641         r = iTask.err_code;
642         goto out_unlock;
643     }
644 
645     iscsi_allocmap_set_allocated(iscsilun, sector_num * BDRV_SECTOR_SIZE,
646                                  nb_sectors * BDRV_SECTOR_SIZE);
647 
648 out_unlock:
649     qemu_mutex_unlock(&iscsilun->mutex);
650     g_free(iTask.err_str);
651     return r;
652 }
653 
654 
655 
656 static int coroutine_fn iscsi_co_block_status(BlockDriverState *bs,
657                                               bool want_zero, int64_t offset,
658                                               int64_t bytes, int64_t *pnum,
659                                               int64_t *map,
660                                               BlockDriverState **file)
661 {
662     IscsiLun *iscsilun = bs->opaque;
663     struct scsi_get_lba_status *lbas = NULL;
664     struct scsi_lba_status_descriptor *lbasd = NULL;
665     struct IscsiTask iTask;
666     uint64_t lba;
667     int ret;
668 
669     iscsi_co_init_iscsitask(iscsilun, &iTask);
670 
671     assert(QEMU_IS_ALIGNED(offset | bytes, iscsilun->block_size));
672 
673     /* default to all sectors allocated */
674     ret = BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID;
675     if (map) {
676         *map = offset;
677     }
678     *pnum = bytes;
679 
680     /* LUN does not support logical block provisioning */
681     if (!iscsilun->lbpme) {
682         goto out;
683     }
684 
685     lba = offset / iscsilun->block_size;
686 
687     qemu_mutex_lock(&iscsilun->mutex);
688 retry:
689     if (iscsi_get_lba_status_task(iscsilun->iscsi, iscsilun->lun,
690                                   lba, 8 + 16, iscsi_co_generic_cb,
691                                   &iTask) == NULL) {
692         ret = -ENOMEM;
693         goto out_unlock;
694     }
695 
696     while (!iTask.complete) {
697         iscsi_set_events(iscsilun);
698         qemu_mutex_unlock(&iscsilun->mutex);
699         qemu_coroutine_yield();
700         qemu_mutex_lock(&iscsilun->mutex);
701     }
702 
703     if (iTask.do_retry) {
704         if (iTask.task != NULL) {
705             scsi_free_scsi_task(iTask.task);
706             iTask.task = NULL;
707         }
708         iTask.complete = 0;
709         goto retry;
710     }
711 
712     if (iTask.status != SCSI_STATUS_GOOD) {
713         /* in case the get_lba_status_callout fails (i.e.
714          * because the device is busy or the cmd is not
715          * supported) we pretend all blocks are allocated
716          * for backwards compatibility */
717         error_report("iSCSI GET_LBA_STATUS failed at lba %" PRIu64 ": %s",
718                      lba, iTask.err_str);
719         goto out_unlock;
720     }
721 
722     lbas = scsi_datain_unmarshall(iTask.task);
723     if (lbas == NULL) {
724         ret = -EIO;
725         goto out_unlock;
726     }
727 
728     lbasd = &lbas->descriptors[0];
729 
730     if (lba != lbasd->lba) {
731         ret = -EIO;
732         goto out_unlock;
733     }
734 
735     *pnum = lbasd->num_blocks * iscsilun->block_size;
736 
737     if (lbasd->provisioning == SCSI_PROVISIONING_TYPE_DEALLOCATED ||
738         lbasd->provisioning == SCSI_PROVISIONING_TYPE_ANCHORED) {
739         ret &= ~BDRV_BLOCK_DATA;
740         if (iscsilun->lbprz) {
741             ret |= BDRV_BLOCK_ZERO;
742         }
743     }
744 
745     if (ret & BDRV_BLOCK_ZERO) {
746         iscsi_allocmap_set_unallocated(iscsilun, offset, *pnum);
747     } else {
748         iscsi_allocmap_set_allocated(iscsilun, offset, *pnum);
749     }
750 
751     if (*pnum > bytes) {
752         *pnum = bytes;
753     }
754 out_unlock:
755     qemu_mutex_unlock(&iscsilun->mutex);
756     g_free(iTask.err_str);
757 out:
758     if (iTask.task != NULL) {
759         scsi_free_scsi_task(iTask.task);
760     }
761     if (ret > 0 && ret & BDRV_BLOCK_OFFSET_VALID && file) {
762         *file = bs;
763     }
764     return ret;
765 }
766 
767 static int coroutine_fn iscsi_co_readv(BlockDriverState *bs,
768                                        int64_t sector_num, int nb_sectors,
769                                        QEMUIOVector *iov)
770 {
771     IscsiLun *iscsilun = bs->opaque;
772     struct IscsiTask iTask;
773     uint64_t lba;
774     uint32_t num_sectors;
775     int r = 0;
776 
777     if (!is_sector_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
778         return -EINVAL;
779     }
780 
781     if (bs->bl.max_transfer) {
782         assert(nb_sectors << BDRV_SECTOR_BITS <= bs->bl.max_transfer);
783     }
784 
785     /* if cache.direct is off and we have a valid entry in our allocation map
786      * we can skip checking the block status and directly return zeroes if
787      * the request falls within an unallocated area */
788     if (iscsi_allocmap_is_valid(iscsilun, sector_num * BDRV_SECTOR_SIZE,
789                                 nb_sectors * BDRV_SECTOR_SIZE) &&
790         !iscsi_allocmap_is_allocated(iscsilun, sector_num * BDRV_SECTOR_SIZE,
791                                      nb_sectors * BDRV_SECTOR_SIZE)) {
792             qemu_iovec_memset(iov, 0, 0x00, iov->size);
793             return 0;
794     }
795 
796     if (nb_sectors >= ISCSI_CHECKALLOC_THRES &&
797         !iscsi_allocmap_is_valid(iscsilun, sector_num * BDRV_SECTOR_SIZE,
798                                  nb_sectors * BDRV_SECTOR_SIZE) &&
799         !iscsi_allocmap_is_allocated(iscsilun, sector_num * BDRV_SECTOR_SIZE,
800                                      nb_sectors * BDRV_SECTOR_SIZE)) {
801         int64_t pnum;
802         /* check the block status from the beginning of the cluster
803          * containing the start sector */
804         int64_t head;
805         int ret;
806 
807         assert(iscsilun->cluster_size);
808         head = (sector_num * BDRV_SECTOR_SIZE) % iscsilun->cluster_size;
809         ret = iscsi_co_block_status(bs, true,
810                                     sector_num * BDRV_SECTOR_SIZE - head,
811                                     BDRV_REQUEST_MAX_BYTES, &pnum, NULL, NULL);
812         if (ret < 0) {
813             return ret;
814         }
815         /* if the whole request falls into an unallocated area we can avoid
816          * reading and directly return zeroes instead */
817         if (ret & BDRV_BLOCK_ZERO &&
818             pnum >= nb_sectors * BDRV_SECTOR_SIZE + head) {
819             qemu_iovec_memset(iov, 0, 0x00, iov->size);
820             return 0;
821         }
822     }
823 
824     lba = sector_qemu2lun(sector_num, iscsilun);
825     num_sectors = sector_qemu2lun(nb_sectors, iscsilun);
826 
827     iscsi_co_init_iscsitask(iscsilun, &iTask);
828     qemu_mutex_lock(&iscsilun->mutex);
829 retry:
830     if (iscsilun->use_16_for_rw) {
831 #if LIBISCSI_API_VERSION >= (20160603)
832         iTask.task = iscsi_read16_iov_task(iscsilun->iscsi, iscsilun->lun, lba,
833                                            num_sectors * iscsilun->block_size,
834                                            iscsilun->block_size, 0, 0, 0, 0, 0,
835                                            iscsi_co_generic_cb, &iTask,
836                                            (struct scsi_iovec *)iov->iov, iov->niov);
837     } else {
838         iTask.task = iscsi_read10_iov_task(iscsilun->iscsi, iscsilun->lun, lba,
839                                            num_sectors * iscsilun->block_size,
840                                            iscsilun->block_size,
841                                            0, 0, 0, 0, 0,
842                                            iscsi_co_generic_cb, &iTask,
843                                            (struct scsi_iovec *)iov->iov, iov->niov);
844     }
845 #else
846         iTask.task = iscsi_read16_task(iscsilun->iscsi, iscsilun->lun, lba,
847                                        num_sectors * iscsilun->block_size,
848                                        iscsilun->block_size, 0, 0, 0, 0, 0,
849                                        iscsi_co_generic_cb, &iTask);
850     } else {
851         iTask.task = iscsi_read10_task(iscsilun->iscsi, iscsilun->lun, lba,
852                                        num_sectors * iscsilun->block_size,
853                                        iscsilun->block_size,
854                                        0, 0, 0, 0, 0,
855                                        iscsi_co_generic_cb, &iTask);
856     }
857 #endif
858     if (iTask.task == NULL) {
859         qemu_mutex_unlock(&iscsilun->mutex);
860         return -ENOMEM;
861     }
862 #if LIBISCSI_API_VERSION < (20160603)
863     scsi_task_set_iov_in(iTask.task, (struct scsi_iovec *) iov->iov, iov->niov);
864 #endif
865     while (!iTask.complete) {
866         iscsi_set_events(iscsilun);
867         qemu_mutex_unlock(&iscsilun->mutex);
868         qemu_coroutine_yield();
869         qemu_mutex_lock(&iscsilun->mutex);
870     }
871 
872     if (iTask.task != NULL) {
873         scsi_free_scsi_task(iTask.task);
874         iTask.task = NULL;
875     }
876 
877     if (iTask.do_retry) {
878         iTask.complete = 0;
879         goto retry;
880     }
881 
882     if (iTask.status != SCSI_STATUS_GOOD) {
883         error_report("iSCSI READ10/16 failed at lba %" PRIu64 ": %s",
884                      lba, iTask.err_str);
885         r = iTask.err_code;
886     }
887 
888     qemu_mutex_unlock(&iscsilun->mutex);
889     g_free(iTask.err_str);
890     return r;
891 }
892 
893 static int coroutine_fn iscsi_co_flush(BlockDriverState *bs)
894 {
895     IscsiLun *iscsilun = bs->opaque;
896     struct IscsiTask iTask;
897     int r = 0;
898 
899     iscsi_co_init_iscsitask(iscsilun, &iTask);
900     qemu_mutex_lock(&iscsilun->mutex);
901 retry:
902     if (iscsi_synchronizecache10_task(iscsilun->iscsi, iscsilun->lun, 0, 0, 0,
903                                       0, iscsi_co_generic_cb, &iTask) == NULL) {
904         qemu_mutex_unlock(&iscsilun->mutex);
905         return -ENOMEM;
906     }
907 
908     while (!iTask.complete) {
909         iscsi_set_events(iscsilun);
910         qemu_mutex_unlock(&iscsilun->mutex);
911         qemu_coroutine_yield();
912         qemu_mutex_lock(&iscsilun->mutex);
913     }
914 
915     if (iTask.task != NULL) {
916         scsi_free_scsi_task(iTask.task);
917         iTask.task = NULL;
918     }
919 
920     if (iTask.do_retry) {
921         iTask.complete = 0;
922         goto retry;
923     }
924 
925     if (iTask.status != SCSI_STATUS_GOOD) {
926         error_report("iSCSI SYNCHRONIZECACHE10 failed: %s", iTask.err_str);
927         r = iTask.err_code;
928     }
929 
930     qemu_mutex_unlock(&iscsilun->mutex);
931     g_free(iTask.err_str);
932     return r;
933 }
934 
935 #ifdef __linux__
936 /* Called (via iscsi_service) with QemuMutex held.  */
937 static void
938 iscsi_aio_ioctl_cb(struct iscsi_context *iscsi, int status,
939                      void *command_data, void *opaque)
940 {
941     IscsiAIOCB *acb = opaque;
942 
943     g_free(acb->buf);
944     acb->buf = NULL;
945 
946     acb->status = 0;
947     if (status < 0) {
948         error_report("Failed to ioctl(SG_IO) to iSCSI lun. %s",
949                      iscsi_get_error(iscsi));
950         acb->status = iscsi_translate_sense(&acb->task->sense);
951     }
952 
953     acb->ioh->driver_status = 0;
954     acb->ioh->host_status   = 0;
955     acb->ioh->resid         = 0;
956     acb->ioh->status        = status;
957 
958 #define SG_ERR_DRIVER_SENSE    0x08
959 
960     if (status == SCSI_STATUS_CHECK_CONDITION && acb->task->datain.size >= 2) {
961         int ss;
962 
963         acb->ioh->driver_status |= SG_ERR_DRIVER_SENSE;
964 
965         acb->ioh->sb_len_wr = acb->task->datain.size - 2;
966         ss = (acb->ioh->mx_sb_len >= acb->ioh->sb_len_wr) ?
967              acb->ioh->mx_sb_len : acb->ioh->sb_len_wr;
968         memcpy(acb->ioh->sbp, &acb->task->datain.data[2], ss);
969     }
970 
971     iscsi_schedule_bh(acb);
972 }
973 
974 static void iscsi_ioctl_bh_completion(void *opaque)
975 {
976     IscsiAIOCB *acb = opaque;
977 
978     qemu_bh_delete(acb->bh);
979     acb->common.cb(acb->common.opaque, acb->ret);
980     qemu_aio_unref(acb);
981 }
982 
983 static void iscsi_ioctl_handle_emulated(IscsiAIOCB *acb, int req, void *buf)
984 {
985     BlockDriverState *bs = acb->common.bs;
986     IscsiLun *iscsilun = bs->opaque;
987     int ret = 0;
988 
989     switch (req) {
990     case SG_GET_VERSION_NUM:
991         *(int *)buf = 30000;
992         break;
993     case SG_GET_SCSI_ID:
994         ((struct sg_scsi_id *)buf)->scsi_type = iscsilun->type;
995         break;
996     default:
997         ret = -EINVAL;
998     }
999     assert(!acb->bh);
1000     acb->bh = aio_bh_new(bdrv_get_aio_context(bs),
1001                          iscsi_ioctl_bh_completion, acb);
1002     acb->ret = ret;
1003     qemu_bh_schedule(acb->bh);
1004 }
1005 
1006 static BlockAIOCB *iscsi_aio_ioctl(BlockDriverState *bs,
1007         unsigned long int req, void *buf,
1008         BlockCompletionFunc *cb, void *opaque)
1009 {
1010     IscsiLun *iscsilun = bs->opaque;
1011     struct iscsi_context *iscsi = iscsilun->iscsi;
1012     struct iscsi_data data;
1013     IscsiAIOCB *acb;
1014 
1015     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
1016 
1017     acb->iscsilun = iscsilun;
1018     acb->bh          = NULL;
1019     acb->status      = -EINPROGRESS;
1020     acb->buf         = NULL;
1021     acb->ioh         = buf;
1022 
1023     if (req != SG_IO) {
1024         iscsi_ioctl_handle_emulated(acb, req, buf);
1025         return &acb->common;
1026     }
1027 
1028     if (acb->ioh->cmd_len > SCSI_CDB_MAX_SIZE) {
1029         error_report("iSCSI: ioctl error CDB exceeds max size (%d > %d)",
1030                      acb->ioh->cmd_len, SCSI_CDB_MAX_SIZE);
1031         qemu_aio_unref(acb);
1032         return NULL;
1033     }
1034 
1035     acb->task = malloc(sizeof(struct scsi_task));
1036     if (acb->task == NULL) {
1037         error_report("iSCSI: Failed to allocate task for scsi command. %s",
1038                      iscsi_get_error(iscsi));
1039         qemu_aio_unref(acb);
1040         return NULL;
1041     }
1042     memset(acb->task, 0, sizeof(struct scsi_task));
1043 
1044     switch (acb->ioh->dxfer_direction) {
1045     case SG_DXFER_TO_DEV:
1046         acb->task->xfer_dir = SCSI_XFER_WRITE;
1047         break;
1048     case SG_DXFER_FROM_DEV:
1049         acb->task->xfer_dir = SCSI_XFER_READ;
1050         break;
1051     default:
1052         acb->task->xfer_dir = SCSI_XFER_NONE;
1053         break;
1054     }
1055 
1056     acb->task->cdb_size = acb->ioh->cmd_len;
1057     memcpy(&acb->task->cdb[0], acb->ioh->cmdp, acb->ioh->cmd_len);
1058     acb->task->expxferlen = acb->ioh->dxfer_len;
1059 
1060     data.size = 0;
1061     qemu_mutex_lock(&iscsilun->mutex);
1062     if (acb->task->xfer_dir == SCSI_XFER_WRITE) {
1063         if (acb->ioh->iovec_count == 0) {
1064             data.data = acb->ioh->dxferp;
1065             data.size = acb->ioh->dxfer_len;
1066         } else {
1067             scsi_task_set_iov_out(acb->task,
1068                                  (struct scsi_iovec *) acb->ioh->dxferp,
1069                                  acb->ioh->iovec_count);
1070         }
1071     }
1072 
1073     if (iscsi_scsi_command_async(iscsi, iscsilun->lun, acb->task,
1074                                  iscsi_aio_ioctl_cb,
1075                                  (data.size > 0) ? &data : NULL,
1076                                  acb) != 0) {
1077         qemu_mutex_unlock(&iscsilun->mutex);
1078         scsi_free_scsi_task(acb->task);
1079         qemu_aio_unref(acb);
1080         return NULL;
1081     }
1082 
1083     /* tell libiscsi to read straight into the buffer we got from ioctl */
1084     if (acb->task->xfer_dir == SCSI_XFER_READ) {
1085         if (acb->ioh->iovec_count == 0) {
1086             scsi_task_add_data_in_buffer(acb->task,
1087                                          acb->ioh->dxfer_len,
1088                                          acb->ioh->dxferp);
1089         } else {
1090             scsi_task_set_iov_in(acb->task,
1091                                  (struct scsi_iovec *) acb->ioh->dxferp,
1092                                  acb->ioh->iovec_count);
1093         }
1094     }
1095 
1096     iscsi_set_events(iscsilun);
1097     qemu_mutex_unlock(&iscsilun->mutex);
1098 
1099     return &acb->common;
1100 }
1101 
1102 #endif
1103 
1104 static int64_t
1105 iscsi_getlength(BlockDriverState *bs)
1106 {
1107     IscsiLun *iscsilun = bs->opaque;
1108     int64_t len;
1109 
1110     len  = iscsilun->num_blocks;
1111     len *= iscsilun->block_size;
1112 
1113     return len;
1114 }
1115 
1116 static int
1117 coroutine_fn iscsi_co_pdiscard(BlockDriverState *bs, int64_t offset, int bytes)
1118 {
1119     IscsiLun *iscsilun = bs->opaque;
1120     struct IscsiTask iTask;
1121     struct unmap_list list;
1122     int r = 0;
1123 
1124     if (!is_byte_request_lun_aligned(offset, bytes, iscsilun)) {
1125         return -ENOTSUP;
1126     }
1127 
1128     if (!iscsilun->lbp.lbpu) {
1129         /* UNMAP is not supported by the target */
1130         return 0;
1131     }
1132 
1133     list.lba = offset / iscsilun->block_size;
1134     list.num = bytes / iscsilun->block_size;
1135 
1136     iscsi_co_init_iscsitask(iscsilun, &iTask);
1137     qemu_mutex_lock(&iscsilun->mutex);
1138 retry:
1139     if (iscsi_unmap_task(iscsilun->iscsi, iscsilun->lun, 0, 0, &list, 1,
1140                          iscsi_co_generic_cb, &iTask) == NULL) {
1141         r = -ENOMEM;
1142         goto out_unlock;
1143     }
1144 
1145     while (!iTask.complete) {
1146         iscsi_set_events(iscsilun);
1147         qemu_mutex_unlock(&iscsilun->mutex);
1148         qemu_coroutine_yield();
1149         qemu_mutex_lock(&iscsilun->mutex);
1150     }
1151 
1152     if (iTask.task != NULL) {
1153         scsi_free_scsi_task(iTask.task);
1154         iTask.task = NULL;
1155     }
1156 
1157     if (iTask.do_retry) {
1158         iTask.complete = 0;
1159         goto retry;
1160     }
1161 
1162     iscsi_allocmap_set_invalid(iscsilun, offset, bytes);
1163 
1164     if (iTask.status == SCSI_STATUS_CHECK_CONDITION) {
1165         /* the target might fail with a check condition if it
1166            is not happy with the alignment of the UNMAP request
1167            we silently fail in this case */
1168         goto out_unlock;
1169     }
1170 
1171     if (iTask.status != SCSI_STATUS_GOOD) {
1172         error_report("iSCSI UNMAP failed at lba %" PRIu64 ": %s",
1173                      list.lba, iTask.err_str);
1174         r = iTask.err_code;
1175         goto out_unlock;
1176     }
1177 
1178 out_unlock:
1179     qemu_mutex_unlock(&iscsilun->mutex);
1180     g_free(iTask.err_str);
1181     return r;
1182 }
1183 
1184 static int
1185 coroutine_fn iscsi_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset,
1186                                     int bytes, BdrvRequestFlags flags)
1187 {
1188     IscsiLun *iscsilun = bs->opaque;
1189     struct IscsiTask iTask;
1190     uint64_t lba;
1191     uint32_t nb_blocks;
1192     bool use_16_for_ws = iscsilun->use_16_for_rw;
1193     int r = 0;
1194 
1195     if (!is_byte_request_lun_aligned(offset, bytes, iscsilun)) {
1196         return -ENOTSUP;
1197     }
1198 
1199     if (flags & BDRV_REQ_MAY_UNMAP) {
1200         if (!use_16_for_ws && !iscsilun->lbp.lbpws10) {
1201             /* WRITESAME10 with UNMAP is unsupported try WRITESAME16 */
1202             use_16_for_ws = true;
1203         }
1204         if (use_16_for_ws && !iscsilun->lbp.lbpws) {
1205             /* WRITESAME16 with UNMAP is not supported by the target,
1206              * fall back and try WRITESAME10/16 without UNMAP */
1207             flags &= ~BDRV_REQ_MAY_UNMAP;
1208             use_16_for_ws = iscsilun->use_16_for_rw;
1209         }
1210     }
1211 
1212     if (!(flags & BDRV_REQ_MAY_UNMAP) && !iscsilun->has_write_same) {
1213         /* WRITESAME without UNMAP is not supported by the target */
1214         return -ENOTSUP;
1215     }
1216 
1217     lba = offset / iscsilun->block_size;
1218     nb_blocks = bytes / iscsilun->block_size;
1219 
1220     if (iscsilun->zeroblock == NULL) {
1221         iscsilun->zeroblock = g_try_malloc0(iscsilun->block_size);
1222         if (iscsilun->zeroblock == NULL) {
1223             return -ENOMEM;
1224         }
1225     }
1226 
1227     qemu_mutex_lock(&iscsilun->mutex);
1228     iscsi_co_init_iscsitask(iscsilun, &iTask);
1229 retry:
1230     if (use_16_for_ws) {
1231         iTask.task = iscsi_writesame16_task(iscsilun->iscsi, iscsilun->lun, lba,
1232                                             iscsilun->zeroblock, iscsilun->block_size,
1233                                             nb_blocks, 0, !!(flags & BDRV_REQ_MAY_UNMAP),
1234                                             0, 0, iscsi_co_generic_cb, &iTask);
1235     } else {
1236         iTask.task = iscsi_writesame10_task(iscsilun->iscsi, iscsilun->lun, lba,
1237                                             iscsilun->zeroblock, iscsilun->block_size,
1238                                             nb_blocks, 0, !!(flags & BDRV_REQ_MAY_UNMAP),
1239                                             0, 0, iscsi_co_generic_cb, &iTask);
1240     }
1241     if (iTask.task == NULL) {
1242         qemu_mutex_unlock(&iscsilun->mutex);
1243         return -ENOMEM;
1244     }
1245 
1246     while (!iTask.complete) {
1247         iscsi_set_events(iscsilun);
1248         qemu_mutex_unlock(&iscsilun->mutex);
1249         qemu_coroutine_yield();
1250         qemu_mutex_lock(&iscsilun->mutex);
1251     }
1252 
1253     if (iTask.status == SCSI_STATUS_CHECK_CONDITION &&
1254         iTask.task->sense.key == SCSI_SENSE_ILLEGAL_REQUEST &&
1255         (iTask.task->sense.ascq == SCSI_SENSE_ASCQ_INVALID_OPERATION_CODE ||
1256          iTask.task->sense.ascq == SCSI_SENSE_ASCQ_INVALID_FIELD_IN_CDB)) {
1257         /* WRITE SAME is not supported by the target */
1258         iscsilun->has_write_same = false;
1259         scsi_free_scsi_task(iTask.task);
1260         r = -ENOTSUP;
1261         goto out_unlock;
1262     }
1263 
1264     if (iTask.task != NULL) {
1265         scsi_free_scsi_task(iTask.task);
1266         iTask.task = NULL;
1267     }
1268 
1269     if (iTask.do_retry) {
1270         iTask.complete = 0;
1271         goto retry;
1272     }
1273 
1274     if (iTask.status != SCSI_STATUS_GOOD) {
1275         iscsi_allocmap_set_invalid(iscsilun, offset, bytes);
1276         error_report("iSCSI WRITESAME10/16 failed at lba %" PRIu64 ": %s",
1277                      lba, iTask.err_str);
1278         r = iTask.err_code;
1279         goto out_unlock;
1280     }
1281 
1282     if (flags & BDRV_REQ_MAY_UNMAP) {
1283         iscsi_allocmap_set_invalid(iscsilun, offset, bytes);
1284     } else {
1285         iscsi_allocmap_set_allocated(iscsilun, offset, bytes);
1286     }
1287 
1288 out_unlock:
1289     qemu_mutex_unlock(&iscsilun->mutex);
1290     g_free(iTask.err_str);
1291     return r;
1292 }
1293 
1294 static void apply_chap(struct iscsi_context *iscsi, QemuOpts *opts,
1295                        Error **errp)
1296 {
1297     const char *user = NULL;
1298     const char *password = NULL;
1299     const char *secretid;
1300     char *secret = NULL;
1301 
1302     user = qemu_opt_get(opts, "user");
1303     if (!user) {
1304         return;
1305     }
1306 
1307     secretid = qemu_opt_get(opts, "password-secret");
1308     password = qemu_opt_get(opts, "password");
1309     if (secretid && password) {
1310         error_setg(errp, "'password' and 'password-secret' properties are "
1311                    "mutually exclusive");
1312         return;
1313     }
1314     if (secretid) {
1315         secret = qcrypto_secret_lookup_as_utf8(secretid, errp);
1316         if (!secret) {
1317             return;
1318         }
1319         password = secret;
1320     } else if (!password) {
1321         error_setg(errp, "CHAP username specified but no password was given");
1322         return;
1323     }
1324 
1325     if (iscsi_set_initiator_username_pwd(iscsi, user, password)) {
1326         error_setg(errp, "Failed to set initiator username and password");
1327     }
1328 
1329     g_free(secret);
1330 }
1331 
1332 static void apply_header_digest(struct iscsi_context *iscsi, QemuOpts *opts,
1333                                 Error **errp)
1334 {
1335     const char *digest = NULL;
1336 
1337     digest = qemu_opt_get(opts, "header-digest");
1338     if (!digest) {
1339         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
1340     } else if (!strcmp(digest, "crc32c")) {
1341         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_CRC32C);
1342     } else if (!strcmp(digest, "none")) {
1343         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE);
1344     } else if (!strcmp(digest, "crc32c-none")) {
1345         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_CRC32C_NONE);
1346     } else if (!strcmp(digest, "none-crc32c")) {
1347         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
1348     } else {
1349         error_setg(errp, "Invalid header-digest setting : %s", digest);
1350     }
1351 }
1352 
1353 static char *get_initiator_name(QemuOpts *opts)
1354 {
1355     const char *name;
1356     char *iscsi_name;
1357     UuidInfo *uuid_info;
1358 
1359     name = qemu_opt_get(opts, "initiator-name");
1360     if (name) {
1361         return g_strdup(name);
1362     }
1363 
1364     uuid_info = qmp_query_uuid(NULL);
1365     if (strcmp(uuid_info->UUID, UUID_NONE) == 0) {
1366         name = qemu_get_vm_name();
1367     } else {
1368         name = uuid_info->UUID;
1369     }
1370     iscsi_name = g_strdup_printf("iqn.2008-11.org.linux-kvm%s%s",
1371                                  name ? ":" : "", name ? name : "");
1372     qapi_free_UuidInfo(uuid_info);
1373     return iscsi_name;
1374 }
1375 
1376 static void iscsi_nop_timed_event(void *opaque)
1377 {
1378     IscsiLun *iscsilun = opaque;
1379 
1380     qemu_mutex_lock(&iscsilun->mutex);
1381     if (iscsi_get_nops_in_flight(iscsilun->iscsi) >= MAX_NOP_FAILURES) {
1382         error_report("iSCSI: NOP timeout. Reconnecting...");
1383         iscsilun->request_timed_out = true;
1384     } else if (iscsi_nop_out_async(iscsilun->iscsi, NULL, NULL, 0, NULL) != 0) {
1385         error_report("iSCSI: failed to sent NOP-Out. Disabling NOP messages.");
1386         goto out;
1387     }
1388 
1389     timer_mod(iscsilun->nop_timer, qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + NOP_INTERVAL);
1390     iscsi_set_events(iscsilun);
1391 
1392 out:
1393     qemu_mutex_unlock(&iscsilun->mutex);
1394 }
1395 
1396 static void iscsi_readcapacity_sync(IscsiLun *iscsilun, Error **errp)
1397 {
1398     struct scsi_task *task = NULL;
1399     struct scsi_readcapacity10 *rc10 = NULL;
1400     struct scsi_readcapacity16 *rc16 = NULL;
1401     int retries = ISCSI_CMD_RETRIES;
1402 
1403     do {
1404         if (task != NULL) {
1405             scsi_free_scsi_task(task);
1406             task = NULL;
1407         }
1408 
1409         switch (iscsilun->type) {
1410         case TYPE_DISK:
1411             task = iscsi_readcapacity16_sync(iscsilun->iscsi, iscsilun->lun);
1412             if (task != NULL && task->status == SCSI_STATUS_GOOD) {
1413                 rc16 = scsi_datain_unmarshall(task);
1414                 if (rc16 == NULL) {
1415                     error_setg(errp, "iSCSI: Failed to unmarshall readcapacity16 data.");
1416                 } else {
1417                     iscsilun->block_size = rc16->block_length;
1418                     iscsilun->num_blocks = rc16->returned_lba + 1;
1419                     iscsilun->lbpme = !!rc16->lbpme;
1420                     iscsilun->lbprz = !!rc16->lbprz;
1421                     iscsilun->use_16_for_rw = (rc16->returned_lba > 0xffffffff);
1422                 }
1423                 break;
1424             }
1425             if (task != NULL && task->status == SCSI_STATUS_CHECK_CONDITION
1426                 && task->sense.key == SCSI_SENSE_UNIT_ATTENTION) {
1427                 break;
1428             }
1429             /* Fall through and try READ CAPACITY(10) instead.  */
1430         case TYPE_ROM:
1431             task = iscsi_readcapacity10_sync(iscsilun->iscsi, iscsilun->lun, 0, 0);
1432             if (task != NULL && task->status == SCSI_STATUS_GOOD) {
1433                 rc10 = scsi_datain_unmarshall(task);
1434                 if (rc10 == NULL) {
1435                     error_setg(errp, "iSCSI: Failed to unmarshall readcapacity10 data.");
1436                 } else {
1437                     iscsilun->block_size = rc10->block_size;
1438                     if (rc10->lba == 0) {
1439                         /* blank disk loaded */
1440                         iscsilun->num_blocks = 0;
1441                     } else {
1442                         iscsilun->num_blocks = rc10->lba + 1;
1443                     }
1444                 }
1445             }
1446             break;
1447         default:
1448             return;
1449         }
1450     } while (task != NULL && task->status == SCSI_STATUS_CHECK_CONDITION
1451              && task->sense.key == SCSI_SENSE_UNIT_ATTENTION
1452              && retries-- > 0);
1453 
1454     if (task == NULL || task->status != SCSI_STATUS_GOOD) {
1455         error_setg(errp, "iSCSI: failed to send readcapacity10/16 command");
1456     } else if (!iscsilun->block_size ||
1457                iscsilun->block_size % BDRV_SECTOR_SIZE) {
1458         error_setg(errp, "iSCSI: the target returned an invalid "
1459                    "block size of %d.", iscsilun->block_size);
1460     }
1461     if (task) {
1462         scsi_free_scsi_task(task);
1463     }
1464 }
1465 
1466 static struct scsi_task *iscsi_do_inquiry(struct iscsi_context *iscsi, int lun,
1467                                           int evpd, int pc, void **inq, Error **errp)
1468 {
1469     int full_size;
1470     struct scsi_task *task = NULL;
1471     task = iscsi_inquiry_sync(iscsi, lun, evpd, pc, 64);
1472     if (task == NULL || task->status != SCSI_STATUS_GOOD) {
1473         goto fail;
1474     }
1475     full_size = scsi_datain_getfullsize(task);
1476     if (full_size > task->datain.size) {
1477         scsi_free_scsi_task(task);
1478 
1479         /* we need more data for the full list */
1480         task = iscsi_inquiry_sync(iscsi, lun, evpd, pc, full_size);
1481         if (task == NULL || task->status != SCSI_STATUS_GOOD) {
1482             goto fail;
1483         }
1484     }
1485 
1486     *inq = scsi_datain_unmarshall(task);
1487     if (*inq == NULL) {
1488         error_setg(errp, "iSCSI: failed to unmarshall inquiry datain blob");
1489         goto fail_with_err;
1490     }
1491 
1492     return task;
1493 
1494 fail:
1495     error_setg(errp, "iSCSI: Inquiry command failed : %s",
1496                iscsi_get_error(iscsi));
1497 fail_with_err:
1498     if (task != NULL) {
1499         scsi_free_scsi_task(task);
1500     }
1501     return NULL;
1502 }
1503 
1504 static void iscsi_detach_aio_context(BlockDriverState *bs)
1505 {
1506     IscsiLun *iscsilun = bs->opaque;
1507 
1508     aio_set_fd_handler(iscsilun->aio_context, iscsi_get_fd(iscsilun->iscsi),
1509                        false, NULL, NULL, NULL, NULL);
1510     iscsilun->events = 0;
1511 
1512     if (iscsilun->nop_timer) {
1513         timer_del(iscsilun->nop_timer);
1514         timer_free(iscsilun->nop_timer);
1515         iscsilun->nop_timer = NULL;
1516     }
1517     if (iscsilun->event_timer) {
1518         timer_del(iscsilun->event_timer);
1519         timer_free(iscsilun->event_timer);
1520         iscsilun->event_timer = NULL;
1521     }
1522 }
1523 
1524 static void iscsi_attach_aio_context(BlockDriverState *bs,
1525                                      AioContext *new_context)
1526 {
1527     IscsiLun *iscsilun = bs->opaque;
1528 
1529     iscsilun->aio_context = new_context;
1530     iscsi_set_events(iscsilun);
1531 
1532     /* Set up a timer for sending out iSCSI NOPs */
1533     iscsilun->nop_timer = aio_timer_new(iscsilun->aio_context,
1534                                         QEMU_CLOCK_REALTIME, SCALE_MS,
1535                                         iscsi_nop_timed_event, iscsilun);
1536     timer_mod(iscsilun->nop_timer,
1537               qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + NOP_INTERVAL);
1538 
1539     /* Set up a timer for periodic calls to iscsi_set_events and to
1540      * scan for command timeout */
1541     iscsilun->event_timer = aio_timer_new(iscsilun->aio_context,
1542                                           QEMU_CLOCK_REALTIME, SCALE_MS,
1543                                           iscsi_timed_check_events, iscsilun);
1544     timer_mod(iscsilun->event_timer,
1545               qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + EVENT_INTERVAL);
1546 }
1547 
1548 static void iscsi_modesense_sync(IscsiLun *iscsilun)
1549 {
1550     struct scsi_task *task;
1551     struct scsi_mode_sense *ms = NULL;
1552     iscsilun->write_protected = false;
1553     iscsilun->dpofua = false;
1554 
1555     task = iscsi_modesense6_sync(iscsilun->iscsi, iscsilun->lun,
1556                                  1, SCSI_MODESENSE_PC_CURRENT,
1557                                  0x3F, 0, 255);
1558     if (task == NULL) {
1559         error_report("iSCSI: Failed to send MODE_SENSE(6) command: %s",
1560                      iscsi_get_error(iscsilun->iscsi));
1561         goto out;
1562     }
1563 
1564     if (task->status != SCSI_STATUS_GOOD) {
1565         error_report("iSCSI: Failed MODE_SENSE(6), LUN assumed writable");
1566         goto out;
1567     }
1568     ms = scsi_datain_unmarshall(task);
1569     if (!ms) {
1570         error_report("iSCSI: Failed to unmarshall MODE_SENSE(6) data: %s",
1571                      iscsi_get_error(iscsilun->iscsi));
1572         goto out;
1573     }
1574     iscsilun->write_protected = ms->device_specific_parameter & 0x80;
1575     iscsilun->dpofua          = ms->device_specific_parameter & 0x10;
1576 
1577 out:
1578     if (task) {
1579         scsi_free_scsi_task(task);
1580     }
1581 }
1582 
1583 static void iscsi_parse_iscsi_option(const char *target, QDict *options)
1584 {
1585     QemuOptsList *list;
1586     QemuOpts *opts;
1587     const char *user, *password, *password_secret, *initiator_name,
1588                *header_digest, *timeout;
1589 
1590     list = qemu_find_opts("iscsi");
1591     if (!list) {
1592         return;
1593     }
1594 
1595     opts = qemu_opts_find(list, target);
1596     if (opts == NULL) {
1597         opts = QTAILQ_FIRST(&list->head);
1598         if (!opts) {
1599             return;
1600         }
1601     }
1602 
1603     user = qemu_opt_get(opts, "user");
1604     if (user) {
1605         qdict_set_default_str(options, "user", user);
1606     }
1607 
1608     password = qemu_opt_get(opts, "password");
1609     if (password) {
1610         qdict_set_default_str(options, "password", password);
1611     }
1612 
1613     password_secret = qemu_opt_get(opts, "password-secret");
1614     if (password_secret) {
1615         qdict_set_default_str(options, "password-secret", password_secret);
1616     }
1617 
1618     initiator_name = qemu_opt_get(opts, "initiator-name");
1619     if (initiator_name) {
1620         qdict_set_default_str(options, "initiator-name", initiator_name);
1621     }
1622 
1623     header_digest = qemu_opt_get(opts, "header-digest");
1624     if (header_digest) {
1625         /* -iscsi takes upper case values, but QAPI only supports lower case
1626          * enum constant names, so we have to convert here. */
1627         char *qapi_value = g_ascii_strdown(header_digest, -1);
1628         qdict_set_default_str(options, "header-digest", qapi_value);
1629         g_free(qapi_value);
1630     }
1631 
1632     timeout = qemu_opt_get(opts, "timeout");
1633     if (timeout) {
1634         qdict_set_default_str(options, "timeout", timeout);
1635     }
1636 }
1637 
1638 /*
1639  * We support iscsi url's on the form
1640  * iscsi://[<username>%<password>@]<host>[:<port>]/<targetname>/<lun>
1641  */
1642 static void iscsi_parse_filename(const char *filename, QDict *options,
1643                                  Error **errp)
1644 {
1645     struct iscsi_url *iscsi_url;
1646     const char *transport_name;
1647     char *lun_str;
1648 
1649     iscsi_url = iscsi_parse_full_url(NULL, filename);
1650     if (iscsi_url == NULL) {
1651         error_setg(errp, "Failed to parse URL : %s", filename);
1652         return;
1653     }
1654 
1655 #if LIBISCSI_API_VERSION >= (20160603)
1656     switch (iscsi_url->transport) {
1657     case TCP_TRANSPORT:
1658         transport_name = "tcp";
1659         break;
1660     case ISER_TRANSPORT:
1661         transport_name = "iser";
1662         break;
1663     default:
1664         error_setg(errp, "Unknown transport type (%d)",
1665                    iscsi_url->transport);
1666         return;
1667     }
1668 #else
1669     transport_name = "tcp";
1670 #endif
1671 
1672     qdict_set_default_str(options, "transport", transport_name);
1673     qdict_set_default_str(options, "portal", iscsi_url->portal);
1674     qdict_set_default_str(options, "target", iscsi_url->target);
1675 
1676     lun_str = g_strdup_printf("%d", iscsi_url->lun);
1677     qdict_set_default_str(options, "lun", lun_str);
1678     g_free(lun_str);
1679 
1680     /* User/password from -iscsi take precedence over those from the URL */
1681     iscsi_parse_iscsi_option(iscsi_url->target, options);
1682 
1683     if (iscsi_url->user[0] != '\0') {
1684         qdict_set_default_str(options, "user", iscsi_url->user);
1685         qdict_set_default_str(options, "password", iscsi_url->passwd);
1686     }
1687 
1688     iscsi_destroy_url(iscsi_url);
1689 }
1690 
1691 static QemuOptsList runtime_opts = {
1692     .name = "iscsi",
1693     .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
1694     .desc = {
1695         {
1696             .name = "transport",
1697             .type = QEMU_OPT_STRING,
1698         },
1699         {
1700             .name = "portal",
1701             .type = QEMU_OPT_STRING,
1702         },
1703         {
1704             .name = "target",
1705             .type = QEMU_OPT_STRING,
1706         },
1707         {
1708             .name = "user",
1709             .type = QEMU_OPT_STRING,
1710         },
1711         {
1712             .name = "password",
1713             .type = QEMU_OPT_STRING,
1714         },
1715         {
1716             .name = "password-secret",
1717             .type = QEMU_OPT_STRING,
1718         },
1719         {
1720             .name = "lun",
1721             .type = QEMU_OPT_NUMBER,
1722         },
1723         {
1724             .name = "initiator-name",
1725             .type = QEMU_OPT_STRING,
1726         },
1727         {
1728             .name = "header-digest",
1729             .type = QEMU_OPT_STRING,
1730         },
1731         {
1732             .name = "timeout",
1733             .type = QEMU_OPT_NUMBER,
1734         },
1735         {
1736             .name = "filename",
1737             .type = QEMU_OPT_STRING,
1738         },
1739         { /* end of list */ }
1740     },
1741 };
1742 
1743 static int iscsi_open(BlockDriverState *bs, QDict *options, int flags,
1744                       Error **errp)
1745 {
1746     IscsiLun *iscsilun = bs->opaque;
1747     struct iscsi_context *iscsi = NULL;
1748     struct scsi_task *task = NULL;
1749     struct scsi_inquiry_standard *inq = NULL;
1750     struct scsi_inquiry_supported_pages *inq_vpd;
1751     char *initiator_name = NULL;
1752     QemuOpts *opts;
1753     Error *local_err = NULL;
1754     const char *transport_name, *portal, *target, *filename;
1755 #if LIBISCSI_API_VERSION >= (20160603)
1756     enum iscsi_transport_type transport;
1757 #endif
1758     int i, ret = 0, timeout = 0, lun;
1759 
1760     /* If we are given a filename, parse the filename, with precedence given to
1761      * filename encoded options */
1762     filename = qdict_get_try_str(options, "filename");
1763     if (filename) {
1764         warn_report("'filename' option specified. "
1765                     "This is an unsupported option, and may be deprecated "
1766                     "in the future");
1767         iscsi_parse_filename(filename, options, &local_err);
1768         if (local_err) {
1769             ret = -EINVAL;
1770             error_propagate(errp, local_err);
1771             goto exit;
1772         }
1773     }
1774 
1775     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
1776     qemu_opts_absorb_qdict(opts, options, &local_err);
1777     if (local_err) {
1778         error_propagate(errp, local_err);
1779         ret = -EINVAL;
1780         goto out;
1781     }
1782 
1783     transport_name = qemu_opt_get(opts, "transport");
1784     portal = qemu_opt_get(opts, "portal");
1785     target = qemu_opt_get(opts, "target");
1786     lun = qemu_opt_get_number(opts, "lun", 0);
1787 
1788     if (!transport_name || !portal || !target) {
1789         error_setg(errp, "Need all of transport, portal and target options");
1790         ret = -EINVAL;
1791         goto out;
1792     }
1793 
1794     if (!strcmp(transport_name, "tcp")) {
1795 #if LIBISCSI_API_VERSION >= (20160603)
1796         transport = TCP_TRANSPORT;
1797     } else if (!strcmp(transport_name, "iser")) {
1798         transport = ISER_TRANSPORT;
1799 #else
1800         /* TCP is what older libiscsi versions always use */
1801 #endif
1802     } else {
1803         error_setg(errp, "Unknown transport: %s", transport_name);
1804         ret = -EINVAL;
1805         goto out;
1806     }
1807 
1808     memset(iscsilun, 0, sizeof(IscsiLun));
1809 
1810     initiator_name = get_initiator_name(opts);
1811 
1812     iscsi = iscsi_create_context(initiator_name);
1813     if (iscsi == NULL) {
1814         error_setg(errp, "iSCSI: Failed to create iSCSI context.");
1815         ret = -ENOMEM;
1816         goto out;
1817     }
1818 #if LIBISCSI_API_VERSION >= (20160603)
1819     if (iscsi_init_transport(iscsi, transport)) {
1820         error_setg(errp, ("Error initializing transport."));
1821         ret = -EINVAL;
1822         goto out;
1823     }
1824 #endif
1825     if (iscsi_set_targetname(iscsi, target)) {
1826         error_setg(errp, "iSCSI: Failed to set target name.");
1827         ret = -EINVAL;
1828         goto out;
1829     }
1830 
1831     /* check if we got CHAP username/password via the options */
1832     apply_chap(iscsi, opts, &local_err);
1833     if (local_err != NULL) {
1834         error_propagate(errp, local_err);
1835         ret = -EINVAL;
1836         goto out;
1837     }
1838 
1839     if (iscsi_set_session_type(iscsi, ISCSI_SESSION_NORMAL) != 0) {
1840         error_setg(errp, "iSCSI: Failed to set session type to normal.");
1841         ret = -EINVAL;
1842         goto out;
1843     }
1844 
1845     /* check if we got HEADER_DIGEST via the options */
1846     apply_header_digest(iscsi, opts, &local_err);
1847     if (local_err != NULL) {
1848         error_propagate(errp, local_err);
1849         ret = -EINVAL;
1850         goto out;
1851     }
1852 
1853     /* timeout handling is broken in libiscsi before 1.15.0 */
1854     timeout = qemu_opt_get_number(opts, "timeout", 0);
1855 #if LIBISCSI_API_VERSION >= 20150621
1856     iscsi_set_timeout(iscsi, timeout);
1857 #else
1858     if (timeout) {
1859         error_report("iSCSI: ignoring timeout value for libiscsi <1.15.0");
1860     }
1861 #endif
1862 
1863     if (iscsi_full_connect_sync(iscsi, portal, lun) != 0) {
1864         error_setg(errp, "iSCSI: Failed to connect to LUN : %s",
1865             iscsi_get_error(iscsi));
1866         ret = -EINVAL;
1867         goto out;
1868     }
1869 
1870     iscsilun->iscsi = iscsi;
1871     iscsilun->aio_context = bdrv_get_aio_context(bs);
1872     iscsilun->lun = lun;
1873     iscsilun->has_write_same = true;
1874 
1875     task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 0, 0,
1876                             (void **) &inq, errp);
1877     if (task == NULL) {
1878         ret = -EINVAL;
1879         goto out;
1880     }
1881     iscsilun->type = inq->periperal_device_type;
1882     scsi_free_scsi_task(task);
1883     task = NULL;
1884 
1885     iscsi_modesense_sync(iscsilun);
1886     if (iscsilun->dpofua) {
1887         bs->supported_write_flags = BDRV_REQ_FUA;
1888     }
1889 
1890     /* Check the write protect flag of the LUN if we want to write */
1891     if (iscsilun->type == TYPE_DISK && (flags & BDRV_O_RDWR) &&
1892         iscsilun->write_protected) {
1893         error_setg(errp, "Cannot open a write protected LUN as read-write");
1894         ret = -EACCES;
1895         goto out;
1896     }
1897 
1898     iscsi_readcapacity_sync(iscsilun, &local_err);
1899     if (local_err != NULL) {
1900         error_propagate(errp, local_err);
1901         ret = -EINVAL;
1902         goto out;
1903     }
1904     bs->total_sectors = sector_lun2qemu(iscsilun->num_blocks, iscsilun);
1905 
1906     /* We don't have any emulation for devices other than disks and CD-ROMs, so
1907      * this must be sg ioctl compatible. We force it to be sg, otherwise qemu
1908      * will try to read from the device to guess the image format.
1909      */
1910     if (iscsilun->type != TYPE_DISK && iscsilun->type != TYPE_ROM) {
1911         bs->sg = true;
1912     }
1913 
1914     task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 1,
1915                             SCSI_INQUIRY_PAGECODE_SUPPORTED_VPD_PAGES,
1916                             (void **) &inq_vpd, errp);
1917     if (task == NULL) {
1918         ret = -EINVAL;
1919         goto out;
1920     }
1921     for (i = 0; i < inq_vpd->num_pages; i++) {
1922         struct scsi_task *inq_task;
1923         struct scsi_inquiry_logical_block_provisioning *inq_lbp;
1924         struct scsi_inquiry_block_limits *inq_bl;
1925         switch (inq_vpd->pages[i]) {
1926         case SCSI_INQUIRY_PAGECODE_LOGICAL_BLOCK_PROVISIONING:
1927             inq_task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 1,
1928                                         SCSI_INQUIRY_PAGECODE_LOGICAL_BLOCK_PROVISIONING,
1929                                         (void **) &inq_lbp, errp);
1930             if (inq_task == NULL) {
1931                 ret = -EINVAL;
1932                 goto out;
1933             }
1934             memcpy(&iscsilun->lbp, inq_lbp,
1935                    sizeof(struct scsi_inquiry_logical_block_provisioning));
1936             scsi_free_scsi_task(inq_task);
1937             break;
1938         case SCSI_INQUIRY_PAGECODE_BLOCK_LIMITS:
1939             inq_task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 1,
1940                                     SCSI_INQUIRY_PAGECODE_BLOCK_LIMITS,
1941                                     (void **) &inq_bl, errp);
1942             if (inq_task == NULL) {
1943                 ret = -EINVAL;
1944                 goto out;
1945             }
1946             memcpy(&iscsilun->bl, inq_bl,
1947                    sizeof(struct scsi_inquiry_block_limits));
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 exit:
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     g_free(iscsilun->zeroblock);
2007     iscsi_allocmap_free(iscsilun);
2008     qemu_mutex_destroy(&iscsilun->mutex);
2009     memset(iscsilun, 0, sizeof(IscsiLun));
2010 }
2011 
2012 static void iscsi_refresh_limits(BlockDriverState *bs, Error **errp)
2013 {
2014     /* We don't actually refresh here, but just return data queried in
2015      * iscsi_open(): iscsi targets don't change their limits. */
2016 
2017     IscsiLun *iscsilun = bs->opaque;
2018     uint64_t max_xfer_len = iscsilun->use_16_for_rw ? 0xffffffff : 0xffff;
2019     unsigned int block_size = MAX(BDRV_SECTOR_SIZE, iscsilun->block_size);
2020 
2021     assert(iscsilun->block_size >= BDRV_SECTOR_SIZE || bs->sg);
2022 
2023     bs->bl.request_alignment = block_size;
2024 
2025     if (iscsilun->bl.max_xfer_len) {
2026         max_xfer_len = MIN(max_xfer_len, iscsilun->bl.max_xfer_len);
2027     }
2028 
2029     if (max_xfer_len * block_size < INT_MAX) {
2030         bs->bl.max_transfer = max_xfer_len * iscsilun->block_size;
2031     }
2032 
2033     if (iscsilun->lbp.lbpu) {
2034         if (iscsilun->bl.max_unmap < 0xffffffff / block_size) {
2035             bs->bl.max_pdiscard =
2036                 iscsilun->bl.max_unmap * iscsilun->block_size;
2037         }
2038         bs->bl.pdiscard_alignment =
2039             iscsilun->bl.opt_unmap_gran * iscsilun->block_size;
2040     } else {
2041         bs->bl.pdiscard_alignment = iscsilun->block_size;
2042     }
2043 
2044     if (iscsilun->bl.max_ws_len < 0xffffffff / block_size) {
2045         bs->bl.max_pwrite_zeroes =
2046             iscsilun->bl.max_ws_len * iscsilun->block_size;
2047     }
2048     if (iscsilun->lbp.lbpws) {
2049         bs->bl.pwrite_zeroes_alignment =
2050             iscsilun->bl.opt_unmap_gran * iscsilun->block_size;
2051     } else {
2052         bs->bl.pwrite_zeroes_alignment = iscsilun->block_size;
2053     }
2054     if (iscsilun->bl.opt_xfer_len &&
2055         iscsilun->bl.opt_xfer_len < INT_MAX / block_size) {
2056         bs->bl.opt_transfer = pow2floor(iscsilun->bl.opt_xfer_len *
2057                                         iscsilun->block_size);
2058     }
2059 }
2060 
2061 /* Note that this will not re-establish a connection with an iSCSI target - it
2062  * is effectively a NOP.  */
2063 static int iscsi_reopen_prepare(BDRVReopenState *state,
2064                                 BlockReopenQueue *queue, Error **errp)
2065 {
2066     IscsiLun *iscsilun = state->bs->opaque;
2067 
2068     if (state->flags & BDRV_O_RDWR && iscsilun->write_protected) {
2069         error_setg(errp, "Cannot open a write protected LUN as read-write");
2070         return -EACCES;
2071     }
2072     return 0;
2073 }
2074 
2075 static void iscsi_reopen_commit(BDRVReopenState *reopen_state)
2076 {
2077     IscsiLun *iscsilun = reopen_state->bs->opaque;
2078 
2079     /* the cache.direct status might have changed */
2080     if (iscsilun->allocmap != NULL) {
2081         iscsi_allocmap_init(iscsilun, reopen_state->flags);
2082     }
2083 }
2084 
2085 static int iscsi_truncate(BlockDriverState *bs, int64_t offset,
2086                           PreallocMode prealloc, Error **errp)
2087 {
2088     IscsiLun *iscsilun = bs->opaque;
2089     Error *local_err = NULL;
2090 
2091     if (prealloc != PREALLOC_MODE_OFF) {
2092         error_setg(errp, "Unsupported preallocation mode '%s'",
2093                    PreallocMode_str(prealloc));
2094         return -ENOTSUP;
2095     }
2096 
2097     if (iscsilun->type != TYPE_DISK) {
2098         error_setg(errp, "Cannot resize non-disk iSCSI devices");
2099         return -ENOTSUP;
2100     }
2101 
2102     iscsi_readcapacity_sync(iscsilun, &local_err);
2103     if (local_err != NULL) {
2104         error_propagate(errp, local_err);
2105         return -EIO;
2106     }
2107 
2108     if (offset > iscsi_getlength(bs)) {
2109         error_setg(errp, "Cannot grow iSCSI devices");
2110         return -EINVAL;
2111     }
2112 
2113     if (iscsilun->allocmap != NULL) {
2114         iscsi_allocmap_init(iscsilun, bs->open_flags);
2115     }
2116 
2117     return 0;
2118 }
2119 
2120 static int coroutine_fn iscsi_co_create_opts(const char *filename, QemuOpts *opts,
2121                                              Error **errp)
2122 {
2123     int ret = 0;
2124     int64_t total_size = 0;
2125     BlockDriverState *bs;
2126     IscsiLun *iscsilun = NULL;
2127     QDict *bs_options;
2128     Error *local_err = NULL;
2129 
2130     bs = bdrv_new();
2131 
2132     /* Read out options */
2133     total_size = DIV_ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
2134                               BDRV_SECTOR_SIZE);
2135     bs->opaque = g_new0(struct IscsiLun, 1);
2136     iscsilun = bs->opaque;
2137 
2138     bs_options = qdict_new();
2139     iscsi_parse_filename(filename, bs_options, &local_err);
2140     if (local_err) {
2141         error_propagate(errp, local_err);
2142         ret = -EINVAL;
2143     } else {
2144         ret = iscsi_open(bs, bs_options, 0, NULL);
2145     }
2146     QDECREF(bs_options);
2147 
2148     if (ret != 0) {
2149         goto out;
2150     }
2151     iscsi_detach_aio_context(bs);
2152     if (iscsilun->type != TYPE_DISK) {
2153         ret = -ENODEV;
2154         goto out;
2155     }
2156     if (bs->total_sectors < total_size) {
2157         ret = -ENOSPC;
2158         goto out;
2159     }
2160 
2161     ret = 0;
2162 out:
2163     if (iscsilun->iscsi != NULL) {
2164         iscsi_destroy_context(iscsilun->iscsi);
2165     }
2166     g_free(bs->opaque);
2167     bs->opaque = NULL;
2168     bdrv_unref(bs);
2169     return ret;
2170 }
2171 
2172 static int iscsi_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
2173 {
2174     IscsiLun *iscsilun = bs->opaque;
2175     bdi->unallocated_blocks_are_zero = iscsilun->lbprz;
2176     bdi->cluster_size = iscsilun->cluster_size;
2177     return 0;
2178 }
2179 
2180 static void coroutine_fn iscsi_co_invalidate_cache(BlockDriverState *bs,
2181                                                    Error **errp)
2182 {
2183     IscsiLun *iscsilun = bs->opaque;
2184     iscsi_allocmap_invalidate(iscsilun);
2185 }
2186 
2187 static QemuOptsList iscsi_create_opts = {
2188     .name = "iscsi-create-opts",
2189     .head = QTAILQ_HEAD_INITIALIZER(iscsi_create_opts.head),
2190     .desc = {
2191         {
2192             .name = BLOCK_OPT_SIZE,
2193             .type = QEMU_OPT_SIZE,
2194             .help = "Virtual disk size"
2195         },
2196         { /* end of list */ }
2197     }
2198 };
2199 
2200 static BlockDriver bdrv_iscsi = {
2201     .format_name     = "iscsi",
2202     .protocol_name   = "iscsi",
2203 
2204     .instance_size          = sizeof(IscsiLun),
2205     .bdrv_parse_filename    = iscsi_parse_filename,
2206     .bdrv_file_open         = iscsi_open,
2207     .bdrv_close             = iscsi_close,
2208     .bdrv_co_create_opts    = iscsi_co_create_opts,
2209     .create_opts            = &iscsi_create_opts,
2210     .bdrv_reopen_prepare    = iscsi_reopen_prepare,
2211     .bdrv_reopen_commit     = iscsi_reopen_commit,
2212     .bdrv_co_invalidate_cache = iscsi_co_invalidate_cache,
2213 
2214     .bdrv_getlength  = iscsi_getlength,
2215     .bdrv_get_info   = iscsi_get_info,
2216     .bdrv_truncate   = iscsi_truncate,
2217     .bdrv_refresh_limits = iscsi_refresh_limits,
2218 
2219     .bdrv_co_block_status  = iscsi_co_block_status,
2220     .bdrv_co_pdiscard      = iscsi_co_pdiscard,
2221     .bdrv_co_pwrite_zeroes = iscsi_co_pwrite_zeroes,
2222     .bdrv_co_readv         = iscsi_co_readv,
2223     .bdrv_co_writev_flags  = iscsi_co_writev_flags,
2224     .bdrv_co_flush_to_disk = iscsi_co_flush,
2225 
2226 #ifdef __linux__
2227     .bdrv_aio_ioctl   = iscsi_aio_ioctl,
2228 #endif
2229 
2230     .bdrv_detach_aio_context = iscsi_detach_aio_context,
2231     .bdrv_attach_aio_context = iscsi_attach_aio_context,
2232 };
2233 
2234 #if LIBISCSI_API_VERSION >= (20160603)
2235 static BlockDriver bdrv_iser = {
2236     .format_name     = "iser",
2237     .protocol_name   = "iser",
2238 
2239     .instance_size          = sizeof(IscsiLun),
2240     .bdrv_parse_filename    = iscsi_parse_filename,
2241     .bdrv_file_open         = iscsi_open,
2242     .bdrv_close             = iscsi_close,
2243     .bdrv_co_create_opts    = iscsi_co_create_opts,
2244     .create_opts            = &iscsi_create_opts,
2245     .bdrv_reopen_prepare    = iscsi_reopen_prepare,
2246     .bdrv_reopen_commit     = iscsi_reopen_commit,
2247     .bdrv_invalidate_cache  = iscsi_invalidate_cache,
2248 
2249     .bdrv_getlength  = iscsi_getlength,
2250     .bdrv_get_info   = iscsi_get_info,
2251     .bdrv_truncate   = iscsi_truncate,
2252     .bdrv_refresh_limits = iscsi_refresh_limits,
2253 
2254     .bdrv_co_block_status  = iscsi_co_block_status,
2255     .bdrv_co_pdiscard      = iscsi_co_pdiscard,
2256     .bdrv_co_pwrite_zeroes = iscsi_co_pwrite_zeroes,
2257     .bdrv_co_readv         = iscsi_co_readv,
2258     .bdrv_co_writev_flags  = iscsi_co_writev_flags,
2259     .bdrv_co_flush_to_disk = iscsi_co_flush,
2260 
2261 #ifdef __linux__
2262     .bdrv_aio_ioctl   = iscsi_aio_ioctl,
2263 #endif
2264 
2265     .bdrv_detach_aio_context = iscsi_detach_aio_context,
2266     .bdrv_attach_aio_context = iscsi_attach_aio_context,
2267 };
2268 #endif
2269 
2270 static void iscsi_block_init(void)
2271 {
2272     bdrv_register(&bdrv_iscsi);
2273 #if LIBISCSI_API_VERSION >= (20160603)
2274     bdrv_register(&bdrv_iser);
2275 #endif
2276 }
2277 
2278 block_init(iscsi_block_init);
2279