xref: /openbmc/qemu/block/iscsi.c (revision acd82796211041c5af43c8c523b85d250c2ccebe)
1 /*
2  * QEMU Block driver for iSCSI images
3  *
4  * Copyright (c) 2010-2011 Ronnie Sahlberg <ronniesahlberg@gmail.com>
5  * Copyright (c) 2012-2016 Peter Lieven <pl@kamp.de>
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy
8  * of this software and associated documentation files (the "Software"), to deal
9  * in the Software without restriction, including without limitation the rights
10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11  * copies of the Software, and to permit persons to whom the Software is
12  * furnished to do so, subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in
15  * all copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23  * THE SOFTWARE.
24  */
25 
26 #include "qemu/osdep.h"
27 
28 #include <poll.h>
29 #include <math.h>
30 #include <arpa/inet.h>
31 #include "qemu-common.h"
32 #include "qemu/config-file.h"
33 #include "qemu/error-report.h"
34 #include "qemu/bitops.h"
35 #include "qemu/bitmap.h"
36 #include "block/block_int.h"
37 #include "block/scsi.h"
38 #include "qemu/iov.h"
39 #include "sysemu/sysemu.h"
40 #include "qmp-commands.h"
41 #include "qapi/qmp/qstring.h"
42 #include "crypto/secret.h"
43 
44 #include <iscsi/iscsi.h>
45 #include <iscsi/scsi-lowlevel.h>
46 
47 #ifdef __linux__
48 #include <scsi/sg.h>
49 #endif
50 
51 typedef struct IscsiLun {
52     struct iscsi_context *iscsi;
53     AioContext *aio_context;
54     int lun;
55     enum scsi_inquiry_peripheral_device_type type;
56     int block_size;
57     uint64_t num_blocks;
58     int events;
59     QEMUTimer *nop_timer;
60     QEMUTimer *event_timer;
61     struct scsi_inquiry_logical_block_provisioning lbp;
62     struct scsi_inquiry_block_limits bl;
63     unsigned char *zeroblock;
64     /* The allocmap tracks which clusters (pages) on the iSCSI target are
65      * allocated and which are not. In case a target returns zeros for
66      * unallocated pages (iscsilun->lprz) we can directly return zeros instead
67      * of reading zeros over the wire if a read request falls within an
68      * unallocated block. As there are 3 possible states we need 2 bitmaps to
69      * track. allocmap_valid keeps track if QEMU's information about a page is
70      * valid. allocmap tracks if a page is allocated or not. In case QEMU has no
71      * valid information about a page the corresponding allocmap entry should be
72      * switched to unallocated as well to force a new lookup of the allocation
73      * status as lookups are generally skipped if a page is suspect to be
74      * allocated. If a iSCSI target is opened with cache.direct = on the
75      * allocmap_valid does not exist turning all cached information invalid so
76      * that a fresh lookup is made for any page even if allocmap entry returns
77      * it's unallocated. */
78     unsigned long *allocmap;
79     unsigned long *allocmap_valid;
80     long allocmap_size;
81     int cluster_sectors;
82     bool use_16_for_rw;
83     bool write_protected;
84     bool lbpme;
85     bool lbprz;
86     bool dpofua;
87     bool has_write_same;
88     bool request_timed_out;
89 } IscsiLun;
90 
91 typedef struct IscsiTask {
92     int status;
93     int complete;
94     int retries;
95     int do_retry;
96     struct scsi_task *task;
97     Coroutine *co;
98     QEMUBH *bh;
99     IscsiLun *iscsilun;
100     QEMUTimer retry_timer;
101     int err_code;
102 } IscsiTask;
103 
104 typedef struct IscsiAIOCB {
105     BlockAIOCB common;
106     QEMUIOVector *qiov;
107     QEMUBH *bh;
108     IscsiLun *iscsilun;
109     struct scsi_task *task;
110     uint8_t *buf;
111     int status;
112     int64_t sector_num;
113     int nb_sectors;
114     int ret;
115 #ifdef __linux__
116     sg_io_hdr_t *ioh;
117 #endif
118 } IscsiAIOCB;
119 
120 /* libiscsi uses time_t so its enough to process events every second */
121 #define EVENT_INTERVAL 1000
122 #define NOP_INTERVAL 5000
123 #define MAX_NOP_FAILURES 3
124 #define ISCSI_CMD_RETRIES ARRAY_SIZE(iscsi_retry_times)
125 static const unsigned iscsi_retry_times[] = {8, 32, 128, 512, 2048, 8192, 32768};
126 
127 /* this threshold is a trade-off knob to choose between
128  * the potential additional overhead of an extra GET_LBA_STATUS request
129  * vs. unnecessarily reading a lot of zero sectors over the wire.
130  * If a read request is greater or equal than ISCSI_CHECKALLOC_THRES
131  * sectors we check the allocation status of the area covered by the
132  * request first if the allocationmap indicates that the area might be
133  * unallocated. */
134 #define ISCSI_CHECKALLOC_THRES 64
135 
136 static void
137 iscsi_bh_cb(void *p)
138 {
139     IscsiAIOCB *acb = p;
140 
141     qemu_bh_delete(acb->bh);
142 
143     g_free(acb->buf);
144     acb->buf = NULL;
145 
146     acb->common.cb(acb->common.opaque, acb->status);
147 
148     if (acb->task != NULL) {
149         scsi_free_scsi_task(acb->task);
150         acb->task = NULL;
151     }
152 
153     qemu_aio_unref(acb);
154 }
155 
156 static void
157 iscsi_schedule_bh(IscsiAIOCB *acb)
158 {
159     if (acb->bh) {
160         return;
161     }
162     acb->bh = aio_bh_new(acb->iscsilun->aio_context, iscsi_bh_cb, acb);
163     qemu_bh_schedule(acb->bh);
164 }
165 
166 static void iscsi_co_generic_bh_cb(void *opaque)
167 {
168     struct IscsiTask *iTask = opaque;
169     iTask->complete = 1;
170     qemu_bh_delete(iTask->bh);
171     qemu_coroutine_enter(iTask->co);
172 }
173 
174 static void iscsi_retry_timer_expired(void *opaque)
175 {
176     struct IscsiTask *iTask = opaque;
177     iTask->complete = 1;
178     if (iTask->co) {
179         qemu_coroutine_enter(iTask->co);
180     }
181 }
182 
183 static inline unsigned exp_random(double mean)
184 {
185     return -mean * log((double)rand() / RAND_MAX);
186 }
187 
188 /* SCSI_SENSE_ASCQ_INVALID_FIELD_IN_PARAMETER_LIST was introduced in
189  * libiscsi 1.10.0, together with other constants we need.  Use it as
190  * a hint that we have to define them ourselves if needed, to keep the
191  * minimum required libiscsi version at 1.9.0.  We use an ASCQ macro for
192  * the test because SCSI_STATUS_* is an enum.
193  *
194  * To guard against future changes where SCSI_SENSE_ASCQ_* also becomes
195  * an enum, check against the LIBISCSI_API_VERSION macro, which was
196  * introduced in 1.11.0.  If it is present, there is no need to define
197  * anything.
198  */
199 #if !defined(SCSI_SENSE_ASCQ_INVALID_FIELD_IN_PARAMETER_LIST) && \
200     !defined(LIBISCSI_API_VERSION)
201 #define SCSI_STATUS_TASK_SET_FULL                          0x28
202 #define SCSI_STATUS_TIMEOUT                                0x0f000002
203 #define SCSI_SENSE_ASCQ_INVALID_FIELD_IN_PARAMETER_LIST    0x2600
204 #define SCSI_SENSE_ASCQ_PARAMETER_LIST_LENGTH_ERROR        0x1a00
205 #endif
206 
207 static int iscsi_translate_sense(struct scsi_sense *sense)
208 {
209     int ret;
210 
211     switch (sense->key) {
212     case SCSI_SENSE_NOT_READY:
213         return -EBUSY;
214     case SCSI_SENSE_DATA_PROTECTION:
215         return -EACCES;
216     case SCSI_SENSE_COMMAND_ABORTED:
217         return -ECANCELED;
218     case SCSI_SENSE_ILLEGAL_REQUEST:
219         /* Parse ASCQ */
220         break;
221     default:
222         return -EIO;
223     }
224     switch (sense->ascq) {
225     case SCSI_SENSE_ASCQ_PARAMETER_LIST_LENGTH_ERROR:
226     case SCSI_SENSE_ASCQ_INVALID_OPERATION_CODE:
227     case SCSI_SENSE_ASCQ_INVALID_FIELD_IN_CDB:
228     case SCSI_SENSE_ASCQ_INVALID_FIELD_IN_PARAMETER_LIST:
229         ret = -EINVAL;
230         break;
231     case SCSI_SENSE_ASCQ_LBA_OUT_OF_RANGE:
232         ret = -ENOSPC;
233         break;
234     case SCSI_SENSE_ASCQ_LOGICAL_UNIT_NOT_SUPPORTED:
235         ret = -ENOTSUP;
236         break;
237     case SCSI_SENSE_ASCQ_MEDIUM_NOT_PRESENT:
238     case SCSI_SENSE_ASCQ_MEDIUM_NOT_PRESENT_TRAY_CLOSED:
239     case SCSI_SENSE_ASCQ_MEDIUM_NOT_PRESENT_TRAY_OPEN:
240         ret = -ENOMEDIUM;
241         break;
242     case SCSI_SENSE_ASCQ_WRITE_PROTECTED:
243         ret = -EACCES;
244         break;
245     default:
246         ret = -EIO;
247         break;
248     }
249     return ret;
250 }
251 
252 static void
253 iscsi_co_generic_cb(struct iscsi_context *iscsi, int status,
254                         void *command_data, void *opaque)
255 {
256     struct IscsiTask *iTask = opaque;
257     struct scsi_task *task = command_data;
258 
259     iTask->status = status;
260     iTask->do_retry = 0;
261     iTask->task = task;
262 
263     if (status != SCSI_STATUS_GOOD) {
264         if (iTask->retries++ < ISCSI_CMD_RETRIES) {
265             if (status == SCSI_STATUS_CHECK_CONDITION
266                 && task->sense.key == SCSI_SENSE_UNIT_ATTENTION) {
267                 error_report("iSCSI CheckCondition: %s",
268                              iscsi_get_error(iscsi));
269                 iTask->do_retry = 1;
270                 goto out;
271             }
272             if (status == SCSI_STATUS_BUSY ||
273                 status == SCSI_STATUS_TIMEOUT ||
274                 status == SCSI_STATUS_TASK_SET_FULL) {
275                 unsigned retry_time =
276                     exp_random(iscsi_retry_times[iTask->retries - 1]);
277                 if (status == SCSI_STATUS_TIMEOUT) {
278                     /* make sure the request is rescheduled AFTER the
279                      * reconnect is initiated */
280                     retry_time = EVENT_INTERVAL * 2;
281                     iTask->iscsilun->request_timed_out = true;
282                 }
283                 error_report("iSCSI Busy/TaskSetFull/TimeOut"
284                              " (retry #%u in %u ms): %s",
285                              iTask->retries, retry_time,
286                              iscsi_get_error(iscsi));
287                 aio_timer_init(iTask->iscsilun->aio_context,
288                                &iTask->retry_timer, QEMU_CLOCK_REALTIME,
289                                SCALE_MS, iscsi_retry_timer_expired, iTask);
290                 timer_mod(&iTask->retry_timer,
291                           qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + retry_time);
292                 iTask->do_retry = 1;
293                 return;
294             }
295         }
296         iTask->err_code = iscsi_translate_sense(&task->sense);
297         error_report("iSCSI Failure: %s", iscsi_get_error(iscsi));
298     }
299 
300 out:
301     if (iTask->co) {
302         iTask->bh = aio_bh_new(iTask->iscsilun->aio_context,
303                                iscsi_co_generic_bh_cb, iTask);
304         qemu_bh_schedule(iTask->bh);
305     } else {
306         iTask->complete = 1;
307     }
308 }
309 
310 static void iscsi_co_init_iscsitask(IscsiLun *iscsilun, struct IscsiTask *iTask)
311 {
312     *iTask = (struct IscsiTask) {
313         .co         = qemu_coroutine_self(),
314         .iscsilun   = iscsilun,
315     };
316 }
317 
318 static void
319 iscsi_abort_task_cb(struct iscsi_context *iscsi, int status, void *command_data,
320                     void *private_data)
321 {
322     IscsiAIOCB *acb = private_data;
323 
324     acb->status = -ECANCELED;
325     iscsi_schedule_bh(acb);
326 }
327 
328 static void
329 iscsi_aio_cancel(BlockAIOCB *blockacb)
330 {
331     IscsiAIOCB *acb = (IscsiAIOCB *)blockacb;
332     IscsiLun *iscsilun = acb->iscsilun;
333 
334     if (acb->status != -EINPROGRESS) {
335         return;
336     }
337 
338     /* send a task mgmt call to the target to cancel the task on the target */
339     iscsi_task_mgmt_abort_task_async(iscsilun->iscsi, acb->task,
340                                      iscsi_abort_task_cb, acb);
341 
342 }
343 
344 static const AIOCBInfo iscsi_aiocb_info = {
345     .aiocb_size         = sizeof(IscsiAIOCB),
346     .cancel_async       = iscsi_aio_cancel,
347 };
348 
349 
350 static void iscsi_process_read(void *arg);
351 static void iscsi_process_write(void *arg);
352 
353 static void
354 iscsi_set_events(IscsiLun *iscsilun)
355 {
356     struct iscsi_context *iscsi = iscsilun->iscsi;
357     int ev = iscsi_which_events(iscsi);
358 
359     if (ev != iscsilun->events) {
360         aio_set_fd_handler(iscsilun->aio_context, iscsi_get_fd(iscsi),
361                            false,
362                            (ev & POLLIN) ? iscsi_process_read : NULL,
363                            (ev & POLLOUT) ? iscsi_process_write : NULL,
364                            iscsilun);
365         iscsilun->events = ev;
366     }
367 }
368 
369 static void iscsi_timed_check_events(void *opaque)
370 {
371     IscsiLun *iscsilun = opaque;
372 
373     /* check for timed out requests */
374     iscsi_service(iscsilun->iscsi, 0);
375 
376     if (iscsilun->request_timed_out) {
377         iscsilun->request_timed_out = false;
378         iscsi_reconnect(iscsilun->iscsi);
379     }
380 
381     /* newer versions of libiscsi may return zero events. Ensure we are able
382      * to return to service once this situation changes. */
383     iscsi_set_events(iscsilun);
384 
385     timer_mod(iscsilun->event_timer,
386               qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + EVENT_INTERVAL);
387 }
388 
389 static void
390 iscsi_process_read(void *arg)
391 {
392     IscsiLun *iscsilun = arg;
393     struct iscsi_context *iscsi = iscsilun->iscsi;
394 
395     iscsi_service(iscsi, POLLIN);
396     iscsi_set_events(iscsilun);
397 }
398 
399 static void
400 iscsi_process_write(void *arg)
401 {
402     IscsiLun *iscsilun = arg;
403     struct iscsi_context *iscsi = iscsilun->iscsi;
404 
405     iscsi_service(iscsi, POLLOUT);
406     iscsi_set_events(iscsilun);
407 }
408 
409 static int64_t sector_lun2qemu(int64_t sector, IscsiLun *iscsilun)
410 {
411     return sector * iscsilun->block_size / BDRV_SECTOR_SIZE;
412 }
413 
414 static int64_t sector_qemu2lun(int64_t sector, IscsiLun *iscsilun)
415 {
416     return sector * BDRV_SECTOR_SIZE / iscsilun->block_size;
417 }
418 
419 static bool is_byte_request_lun_aligned(int64_t offset, int count,
420                                         IscsiLun *iscsilun)
421 {
422     if (offset % iscsilun->block_size || count % iscsilun->block_size) {
423         error_report("iSCSI misaligned request: "
424                      "iscsilun->block_size %u, offset %" PRIi64
425                      ", count %d",
426                      iscsilun->block_size, offset, count);
427         return false;
428     }
429     return true;
430 }
431 
432 static bool is_sector_request_lun_aligned(int64_t sector_num, int nb_sectors,
433                                           IscsiLun *iscsilun)
434 {
435     assert(nb_sectors <= BDRV_REQUEST_MAX_SECTORS);
436     return is_byte_request_lun_aligned(sector_num << BDRV_SECTOR_BITS,
437                                        nb_sectors << BDRV_SECTOR_BITS,
438                                        iscsilun);
439 }
440 
441 static void iscsi_allocmap_free(IscsiLun *iscsilun)
442 {
443     g_free(iscsilun->allocmap);
444     g_free(iscsilun->allocmap_valid);
445     iscsilun->allocmap = NULL;
446     iscsilun->allocmap_valid = NULL;
447 }
448 
449 
450 static int iscsi_allocmap_init(IscsiLun *iscsilun, int open_flags)
451 {
452     iscsi_allocmap_free(iscsilun);
453 
454     iscsilun->allocmap_size =
455         DIV_ROUND_UP(sector_lun2qemu(iscsilun->num_blocks, iscsilun),
456                      iscsilun->cluster_sectors);
457 
458     iscsilun->allocmap = bitmap_try_new(iscsilun->allocmap_size);
459     if (!iscsilun->allocmap) {
460         return -ENOMEM;
461     }
462 
463     if (open_flags & BDRV_O_NOCACHE) {
464         /* in case that cache.direct = on all allocmap entries are
465          * treated as invalid to force a relookup of the block
466          * status on every read request */
467         return 0;
468     }
469 
470     iscsilun->allocmap_valid = bitmap_try_new(iscsilun->allocmap_size);
471     if (!iscsilun->allocmap_valid) {
472         /* if we are under memory pressure free the allocmap as well */
473         iscsi_allocmap_free(iscsilun);
474         return -ENOMEM;
475     }
476 
477     return 0;
478 }
479 
480 static void
481 iscsi_allocmap_update(IscsiLun *iscsilun, int64_t sector_num,
482                       int nb_sectors, bool allocated, bool valid)
483 {
484     int64_t cl_num_expanded, nb_cls_expanded, cl_num_shrunk, nb_cls_shrunk;
485 
486     if (iscsilun->allocmap == NULL) {
487         return;
488     }
489     /* expand to entirely contain all affected clusters */
490     cl_num_expanded = sector_num / iscsilun->cluster_sectors;
491     nb_cls_expanded = DIV_ROUND_UP(sector_num + nb_sectors,
492                                    iscsilun->cluster_sectors) - cl_num_expanded;
493     /* shrink to touch only completely contained clusters */
494     cl_num_shrunk = DIV_ROUND_UP(sector_num, iscsilun->cluster_sectors);
495     nb_cls_shrunk = (sector_num + nb_sectors) / iscsilun->cluster_sectors
496                       - cl_num_shrunk;
497     if (allocated) {
498         bitmap_set(iscsilun->allocmap, cl_num_expanded, nb_cls_expanded);
499     } else {
500         bitmap_clear(iscsilun->allocmap, cl_num_shrunk, nb_cls_shrunk);
501     }
502 
503     if (iscsilun->allocmap_valid == NULL) {
504         return;
505     }
506     if (valid) {
507         bitmap_set(iscsilun->allocmap_valid, cl_num_shrunk, nb_cls_shrunk);
508     } else {
509         bitmap_clear(iscsilun->allocmap_valid, cl_num_expanded,
510                      nb_cls_expanded);
511     }
512 }
513 
514 static void
515 iscsi_allocmap_set_allocated(IscsiLun *iscsilun, int64_t sector_num,
516                              int nb_sectors)
517 {
518     iscsi_allocmap_update(iscsilun, sector_num, nb_sectors, true, true);
519 }
520 
521 static void
522 iscsi_allocmap_set_unallocated(IscsiLun *iscsilun, int64_t sector_num,
523                                int nb_sectors)
524 {
525     /* Note: if cache.direct=on the fifth argument to iscsi_allocmap_update
526      * is ignored, so this will in effect be an iscsi_allocmap_set_invalid.
527      */
528     iscsi_allocmap_update(iscsilun, sector_num, nb_sectors, false, true);
529 }
530 
531 static void iscsi_allocmap_set_invalid(IscsiLun *iscsilun, int64_t sector_num,
532                                        int nb_sectors)
533 {
534     iscsi_allocmap_update(iscsilun, sector_num, nb_sectors, false, false);
535 }
536 
537 static void iscsi_allocmap_invalidate(IscsiLun *iscsilun)
538 {
539     if (iscsilun->allocmap) {
540         bitmap_zero(iscsilun->allocmap, iscsilun->allocmap_size);
541     }
542     if (iscsilun->allocmap_valid) {
543         bitmap_zero(iscsilun->allocmap_valid, iscsilun->allocmap_size);
544     }
545 }
546 
547 static inline bool
548 iscsi_allocmap_is_allocated(IscsiLun *iscsilun, int64_t sector_num,
549                             int nb_sectors)
550 {
551     unsigned long size;
552     if (iscsilun->allocmap == NULL) {
553         return true;
554     }
555     size = DIV_ROUND_UP(sector_num + nb_sectors, iscsilun->cluster_sectors);
556     return !(find_next_bit(iscsilun->allocmap, size,
557                            sector_num / iscsilun->cluster_sectors) == size);
558 }
559 
560 static inline bool iscsi_allocmap_is_valid(IscsiLun *iscsilun,
561                                            int64_t sector_num, int nb_sectors)
562 {
563     unsigned long size;
564     if (iscsilun->allocmap_valid == NULL) {
565         return false;
566     }
567     size = DIV_ROUND_UP(sector_num + nb_sectors, iscsilun->cluster_sectors);
568     return (find_next_zero_bit(iscsilun->allocmap_valid, size,
569                                sector_num / iscsilun->cluster_sectors) == size);
570 }
571 
572 static int coroutine_fn
573 iscsi_co_writev_flags(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 
582     if (fua) {
583         assert(iscsilun->dpofua);
584     }
585     if (!is_sector_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
586         return -EINVAL;
587     }
588 
589     if (bs->bl.max_transfer &&
590         nb_sectors << BDRV_SECTOR_BITS > bs->bl.max_transfer) {
591         error_report("iSCSI Error: Write of %d sectors exceeds max_xfer_len "
592                      "of %" PRIu32 " bytes", nb_sectors, bs->bl.max_transfer);
593         return -EINVAL;
594     }
595 
596     lba = sector_qemu2lun(sector_num, iscsilun);
597     num_sectors = sector_qemu2lun(nb_sectors, iscsilun);
598     iscsi_co_init_iscsitask(iscsilun, &iTask);
599 retry:
600     if (iscsilun->use_16_for_rw) {
601         iTask.task = iscsi_write16_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     } else {
606         iTask.task = iscsi_write10_task(iscsilun->iscsi, iscsilun->lun, lba,
607                                         NULL, num_sectors * iscsilun->block_size,
608                                         iscsilun->block_size, 0, 0, fua, 0, 0,
609                                         iscsi_co_generic_cb, &iTask);
610     }
611     if (iTask.task == NULL) {
612         return -ENOMEM;
613     }
614     scsi_task_set_iov_out(iTask.task, (struct scsi_iovec *) iov->iov,
615                           iov->niov);
616     while (!iTask.complete) {
617         iscsi_set_events(iscsilun);
618         qemu_coroutine_yield();
619     }
620 
621     if (iTask.task != NULL) {
622         scsi_free_scsi_task(iTask.task);
623         iTask.task = NULL;
624     }
625 
626     if (iTask.do_retry) {
627         iTask.complete = 0;
628         goto retry;
629     }
630 
631     if (iTask.status != SCSI_STATUS_GOOD) {
632         iscsi_allocmap_set_invalid(iscsilun, sector_num, nb_sectors);
633         return iTask.err_code;
634     }
635 
636     iscsi_allocmap_set_allocated(iscsilun, sector_num, nb_sectors);
637 
638     return 0;
639 }
640 
641 
642 
643 static int64_t coroutine_fn iscsi_co_get_block_status(BlockDriverState *bs,
644                                                   int64_t sector_num,
645                                                   int nb_sectors, int *pnum,
646                                                   BlockDriverState **file)
647 {
648     IscsiLun *iscsilun = bs->opaque;
649     struct scsi_get_lba_status *lbas = NULL;
650     struct scsi_lba_status_descriptor *lbasd = NULL;
651     struct IscsiTask iTask;
652     int64_t ret;
653 
654     iscsi_co_init_iscsitask(iscsilun, &iTask);
655 
656     if (!is_sector_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
657         ret = -EINVAL;
658         goto out;
659     }
660 
661     /* default to all sectors allocated */
662     ret = BDRV_BLOCK_DATA;
663     ret |= (sector_num << BDRV_SECTOR_BITS) | BDRV_BLOCK_OFFSET_VALID;
664     *pnum = nb_sectors;
665 
666     /* LUN does not support logical block provisioning */
667     if (!iscsilun->lbpme) {
668         goto out;
669     }
670 
671 retry:
672     if (iscsi_get_lba_status_task(iscsilun->iscsi, iscsilun->lun,
673                                   sector_qemu2lun(sector_num, iscsilun),
674                                   8 + 16, iscsi_co_generic_cb,
675                                   &iTask) == NULL) {
676         ret = -ENOMEM;
677         goto out;
678     }
679 
680     while (!iTask.complete) {
681         iscsi_set_events(iscsilun);
682         qemu_coroutine_yield();
683     }
684 
685     if (iTask.do_retry) {
686         if (iTask.task != NULL) {
687             scsi_free_scsi_task(iTask.task);
688             iTask.task = NULL;
689         }
690         iTask.complete = 0;
691         goto retry;
692     }
693 
694     if (iTask.status != SCSI_STATUS_GOOD) {
695         /* in case the get_lba_status_callout fails (i.e.
696          * because the device is busy or the cmd is not
697          * supported) we pretend all blocks are allocated
698          * for backwards compatibility */
699         goto out;
700     }
701 
702     lbas = scsi_datain_unmarshall(iTask.task);
703     if (lbas == NULL) {
704         ret = -EIO;
705         goto out;
706     }
707 
708     lbasd = &lbas->descriptors[0];
709 
710     if (sector_qemu2lun(sector_num, iscsilun) != lbasd->lba) {
711         ret = -EIO;
712         goto out;
713     }
714 
715     *pnum = sector_lun2qemu(lbasd->num_blocks, iscsilun);
716 
717     if (lbasd->provisioning == SCSI_PROVISIONING_TYPE_DEALLOCATED ||
718         lbasd->provisioning == SCSI_PROVISIONING_TYPE_ANCHORED) {
719         ret &= ~BDRV_BLOCK_DATA;
720         if (iscsilun->lbprz) {
721             ret |= BDRV_BLOCK_ZERO;
722         }
723     }
724 
725     if (ret & BDRV_BLOCK_ZERO) {
726         iscsi_allocmap_set_unallocated(iscsilun, sector_num, *pnum);
727     } else {
728         iscsi_allocmap_set_allocated(iscsilun, sector_num, *pnum);
729     }
730 
731     if (*pnum > nb_sectors) {
732         *pnum = nb_sectors;
733     }
734 out:
735     if (iTask.task != NULL) {
736         scsi_free_scsi_task(iTask.task);
737     }
738     if (ret > 0 && ret & BDRV_BLOCK_OFFSET_VALID) {
739         *file = bs;
740     }
741     return ret;
742 }
743 
744 static int coroutine_fn iscsi_co_readv(BlockDriverState *bs,
745                                        int64_t sector_num, int nb_sectors,
746                                        QEMUIOVector *iov)
747 {
748     IscsiLun *iscsilun = bs->opaque;
749     struct IscsiTask iTask;
750     uint64_t lba;
751     uint32_t num_sectors;
752 
753     if (!is_sector_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
754         return -EINVAL;
755     }
756 
757     if (bs->bl.max_transfer &&
758         nb_sectors << BDRV_SECTOR_BITS > bs->bl.max_transfer) {
759         error_report("iSCSI Error: Read of %d sectors exceeds max_xfer_len "
760                      "of %" PRIu32 " bytes", nb_sectors, bs->bl.max_transfer);
761         return -EINVAL;
762     }
763 
764     /* if cache.direct is off and we have a valid entry in our allocation map
765      * we can skip checking the block status and directly return zeroes if
766      * the request falls within an unallocated area */
767     if (iscsi_allocmap_is_valid(iscsilun, sector_num, nb_sectors) &&
768         !iscsi_allocmap_is_allocated(iscsilun, sector_num, nb_sectors)) {
769             qemu_iovec_memset(iov, 0, 0x00, iov->size);
770             return 0;
771     }
772 
773     if (nb_sectors >= ISCSI_CHECKALLOC_THRES &&
774         !iscsi_allocmap_is_valid(iscsilun, sector_num, nb_sectors) &&
775         !iscsi_allocmap_is_allocated(iscsilun, sector_num, nb_sectors)) {
776         int pnum;
777         BlockDriverState *file;
778         /* check the block status from the beginning of the cluster
779          * containing the start sector */
780         int64_t ret = iscsi_co_get_block_status(bs,
781                           sector_num - sector_num % iscsilun->cluster_sectors,
782                           BDRV_REQUEST_MAX_SECTORS, &pnum, &file);
783         if (ret < 0) {
784             return ret;
785         }
786         /* if the whole request falls into an unallocated area we can avoid
787          * to read and directly return zeroes instead */
788         if (ret & BDRV_BLOCK_ZERO &&
789             pnum >= nb_sectors + sector_num % iscsilun->cluster_sectors) {
790             qemu_iovec_memset(iov, 0, 0x00, iov->size);
791             return 0;
792         }
793     }
794 
795     lba = sector_qemu2lun(sector_num, iscsilun);
796     num_sectors = sector_qemu2lun(nb_sectors, iscsilun);
797 
798     iscsi_co_init_iscsitask(iscsilun, &iTask);
799 retry:
800     if (iscsilun->use_16_for_rw) {
801         iTask.task = iscsi_read16_task(iscsilun->iscsi, iscsilun->lun, lba,
802                                        num_sectors * iscsilun->block_size,
803                                        iscsilun->block_size, 0, 0, 0, 0, 0,
804                                        iscsi_co_generic_cb, &iTask);
805     } else {
806         iTask.task = iscsi_read10_task(iscsilun->iscsi, iscsilun->lun, lba,
807                                        num_sectors * iscsilun->block_size,
808                                        iscsilun->block_size,
809                                        0, 0, 0, 0, 0,
810                                        iscsi_co_generic_cb, &iTask);
811     }
812     if (iTask.task == NULL) {
813         return -ENOMEM;
814     }
815     scsi_task_set_iov_in(iTask.task, (struct scsi_iovec *) iov->iov, iov->niov);
816 
817     while (!iTask.complete) {
818         iscsi_set_events(iscsilun);
819         qemu_coroutine_yield();
820     }
821 
822     if (iTask.task != NULL) {
823         scsi_free_scsi_task(iTask.task);
824         iTask.task = NULL;
825     }
826 
827     if (iTask.do_retry) {
828         iTask.complete = 0;
829         goto retry;
830     }
831 
832     if (iTask.status != SCSI_STATUS_GOOD) {
833         return iTask.err_code;
834     }
835 
836     return 0;
837 }
838 
839 static int coroutine_fn iscsi_co_flush(BlockDriverState *bs)
840 {
841     IscsiLun *iscsilun = bs->opaque;
842     struct IscsiTask iTask;
843 
844     iscsi_co_init_iscsitask(iscsilun, &iTask);
845 retry:
846     if (iscsi_synchronizecache10_task(iscsilun->iscsi, iscsilun->lun, 0, 0, 0,
847                                       0, iscsi_co_generic_cb, &iTask) == NULL) {
848         return -ENOMEM;
849     }
850 
851     while (!iTask.complete) {
852         iscsi_set_events(iscsilun);
853         qemu_coroutine_yield();
854     }
855 
856     if (iTask.task != NULL) {
857         scsi_free_scsi_task(iTask.task);
858         iTask.task = NULL;
859     }
860 
861     if (iTask.do_retry) {
862         iTask.complete = 0;
863         goto retry;
864     }
865 
866     if (iTask.status != SCSI_STATUS_GOOD) {
867         return iTask.err_code;
868     }
869 
870     return 0;
871 }
872 
873 #ifdef __linux__
874 static void
875 iscsi_aio_ioctl_cb(struct iscsi_context *iscsi, int status,
876                      void *command_data, void *opaque)
877 {
878     IscsiAIOCB *acb = opaque;
879 
880     g_free(acb->buf);
881     acb->buf = NULL;
882 
883     acb->status = 0;
884     if (status < 0) {
885         error_report("Failed to ioctl(SG_IO) to iSCSI lun. %s",
886                      iscsi_get_error(iscsi));
887         acb->status = iscsi_translate_sense(&acb->task->sense);
888     }
889 
890     acb->ioh->driver_status = 0;
891     acb->ioh->host_status   = 0;
892     acb->ioh->resid         = 0;
893     acb->ioh->status        = status;
894 
895 #define SG_ERR_DRIVER_SENSE    0x08
896 
897     if (status == SCSI_STATUS_CHECK_CONDITION && acb->task->datain.size >= 2) {
898         int ss;
899 
900         acb->ioh->driver_status |= SG_ERR_DRIVER_SENSE;
901 
902         acb->ioh->sb_len_wr = acb->task->datain.size - 2;
903         ss = (acb->ioh->mx_sb_len >= acb->ioh->sb_len_wr) ?
904              acb->ioh->mx_sb_len : acb->ioh->sb_len_wr;
905         memcpy(acb->ioh->sbp, &acb->task->datain.data[2], ss);
906     }
907 
908     iscsi_schedule_bh(acb);
909 }
910 
911 static void iscsi_ioctl_bh_completion(void *opaque)
912 {
913     IscsiAIOCB *acb = opaque;
914 
915     qemu_bh_delete(acb->bh);
916     acb->common.cb(acb->common.opaque, acb->ret);
917     qemu_aio_unref(acb);
918 }
919 
920 static void iscsi_ioctl_handle_emulated(IscsiAIOCB *acb, int req, void *buf)
921 {
922     BlockDriverState *bs = acb->common.bs;
923     IscsiLun *iscsilun = bs->opaque;
924     int ret = 0;
925 
926     switch (req) {
927     case SG_GET_VERSION_NUM:
928         *(int *)buf = 30000;
929         break;
930     case SG_GET_SCSI_ID:
931         ((struct sg_scsi_id *)buf)->scsi_type = iscsilun->type;
932         break;
933     default:
934         ret = -EINVAL;
935     }
936     assert(!acb->bh);
937     acb->bh = aio_bh_new(bdrv_get_aio_context(bs),
938                          iscsi_ioctl_bh_completion, acb);
939     acb->ret = ret;
940     qemu_bh_schedule(acb->bh);
941 }
942 
943 static BlockAIOCB *iscsi_aio_ioctl(BlockDriverState *bs,
944         unsigned long int req, void *buf,
945         BlockCompletionFunc *cb, void *opaque)
946 {
947     IscsiLun *iscsilun = bs->opaque;
948     struct iscsi_context *iscsi = iscsilun->iscsi;
949     struct iscsi_data data;
950     IscsiAIOCB *acb;
951 
952     acb = qemu_aio_get(&iscsi_aiocb_info, bs, cb, opaque);
953 
954     acb->iscsilun = iscsilun;
955     acb->bh          = NULL;
956     acb->status      = -EINPROGRESS;
957     acb->buf         = NULL;
958     acb->ioh         = buf;
959 
960     if (req != SG_IO) {
961         iscsi_ioctl_handle_emulated(acb, req, buf);
962         return &acb->common;
963     }
964 
965     if (acb->ioh->cmd_len > SCSI_CDB_MAX_SIZE) {
966         error_report("iSCSI: ioctl error CDB exceeds max size (%d > %d)",
967                      acb->ioh->cmd_len, SCSI_CDB_MAX_SIZE);
968         qemu_aio_unref(acb);
969         return NULL;
970     }
971 
972     acb->task = malloc(sizeof(struct scsi_task));
973     if (acb->task == NULL) {
974         error_report("iSCSI: Failed to allocate task for scsi command. %s",
975                      iscsi_get_error(iscsi));
976         qemu_aio_unref(acb);
977         return NULL;
978     }
979     memset(acb->task, 0, sizeof(struct scsi_task));
980 
981     switch (acb->ioh->dxfer_direction) {
982     case SG_DXFER_TO_DEV:
983         acb->task->xfer_dir = SCSI_XFER_WRITE;
984         break;
985     case SG_DXFER_FROM_DEV:
986         acb->task->xfer_dir = SCSI_XFER_READ;
987         break;
988     default:
989         acb->task->xfer_dir = SCSI_XFER_NONE;
990         break;
991     }
992 
993     acb->task->cdb_size = acb->ioh->cmd_len;
994     memcpy(&acb->task->cdb[0], acb->ioh->cmdp, acb->ioh->cmd_len);
995     acb->task->expxferlen = acb->ioh->dxfer_len;
996 
997     data.size = 0;
998     if (acb->task->xfer_dir == SCSI_XFER_WRITE) {
999         if (acb->ioh->iovec_count == 0) {
1000             data.data = acb->ioh->dxferp;
1001             data.size = acb->ioh->dxfer_len;
1002         } else {
1003             scsi_task_set_iov_out(acb->task,
1004                                  (struct scsi_iovec *) acb->ioh->dxferp,
1005                                  acb->ioh->iovec_count);
1006         }
1007     }
1008 
1009     if (iscsi_scsi_command_async(iscsi, iscsilun->lun, acb->task,
1010                                  iscsi_aio_ioctl_cb,
1011                                  (data.size > 0) ? &data : NULL,
1012                                  acb) != 0) {
1013         scsi_free_scsi_task(acb->task);
1014         qemu_aio_unref(acb);
1015         return NULL;
1016     }
1017 
1018     /* tell libiscsi to read straight into the buffer we got from ioctl */
1019     if (acb->task->xfer_dir == SCSI_XFER_READ) {
1020         if (acb->ioh->iovec_count == 0) {
1021             scsi_task_add_data_in_buffer(acb->task,
1022                                          acb->ioh->dxfer_len,
1023                                          acb->ioh->dxferp);
1024         } else {
1025             scsi_task_set_iov_in(acb->task,
1026                                  (struct scsi_iovec *) acb->ioh->dxferp,
1027                                  acb->ioh->iovec_count);
1028         }
1029     }
1030 
1031     iscsi_set_events(iscsilun);
1032 
1033     return &acb->common;
1034 }
1035 
1036 #endif
1037 
1038 static int64_t
1039 iscsi_getlength(BlockDriverState *bs)
1040 {
1041     IscsiLun *iscsilun = bs->opaque;
1042     int64_t len;
1043 
1044     len  = iscsilun->num_blocks;
1045     len *= iscsilun->block_size;
1046 
1047     return len;
1048 }
1049 
1050 static int
1051 coroutine_fn iscsi_co_discard(BlockDriverState *bs, int64_t sector_num,
1052                                    int nb_sectors)
1053 {
1054     IscsiLun *iscsilun = bs->opaque;
1055     struct IscsiTask iTask;
1056     struct unmap_list list;
1057 
1058     if (!is_sector_request_lun_aligned(sector_num, nb_sectors, iscsilun)) {
1059         return -EINVAL;
1060     }
1061 
1062     if (!iscsilun->lbp.lbpu) {
1063         /* UNMAP is not supported by the target */
1064         return 0;
1065     }
1066 
1067     list.lba = sector_qemu2lun(sector_num, iscsilun);
1068     list.num = sector_qemu2lun(nb_sectors, iscsilun);
1069 
1070     iscsi_co_init_iscsitask(iscsilun, &iTask);
1071 retry:
1072     if (iscsi_unmap_task(iscsilun->iscsi, iscsilun->lun, 0, 0, &list, 1,
1073                      iscsi_co_generic_cb, &iTask) == NULL) {
1074         return -ENOMEM;
1075     }
1076 
1077     while (!iTask.complete) {
1078         iscsi_set_events(iscsilun);
1079         qemu_coroutine_yield();
1080     }
1081 
1082     if (iTask.task != NULL) {
1083         scsi_free_scsi_task(iTask.task);
1084         iTask.task = NULL;
1085     }
1086 
1087     if (iTask.do_retry) {
1088         iTask.complete = 0;
1089         goto retry;
1090     }
1091 
1092     if (iTask.status == SCSI_STATUS_CHECK_CONDITION) {
1093         /* the target might fail with a check condition if it
1094            is not happy with the alignment of the UNMAP request
1095            we silently fail in this case */
1096         return 0;
1097     }
1098 
1099     if (iTask.status != SCSI_STATUS_GOOD) {
1100         return iTask.err_code;
1101     }
1102 
1103     iscsi_allocmap_set_invalid(iscsilun, sector_num, nb_sectors);
1104 
1105     return 0;
1106 }
1107 
1108 static int
1109 coroutine_fn iscsi_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset,
1110                                     int count, BdrvRequestFlags flags)
1111 {
1112     IscsiLun *iscsilun = bs->opaque;
1113     struct IscsiTask iTask;
1114     uint64_t lba;
1115     uint32_t nb_blocks;
1116     bool use_16_for_ws = iscsilun->use_16_for_rw;
1117 
1118     if (!is_byte_request_lun_aligned(offset, count, iscsilun)) {
1119         return -ENOTSUP;
1120     }
1121 
1122     if (flags & BDRV_REQ_MAY_UNMAP) {
1123         if (!use_16_for_ws && !iscsilun->lbp.lbpws10) {
1124             /* WRITESAME10 with UNMAP is unsupported try WRITESAME16 */
1125             use_16_for_ws = true;
1126         }
1127         if (use_16_for_ws && !iscsilun->lbp.lbpws) {
1128             /* WRITESAME16 with UNMAP is not supported by the target,
1129              * fall back and try WRITESAME10/16 without UNMAP */
1130             flags &= ~BDRV_REQ_MAY_UNMAP;
1131             use_16_for_ws = iscsilun->use_16_for_rw;
1132         }
1133     }
1134 
1135     if (!(flags & BDRV_REQ_MAY_UNMAP) && !iscsilun->has_write_same) {
1136         /* WRITESAME without UNMAP is not supported by the target */
1137         return -ENOTSUP;
1138     }
1139 
1140     lba = offset / iscsilun->block_size;
1141     nb_blocks = count / iscsilun->block_size;
1142 
1143     if (iscsilun->zeroblock == NULL) {
1144         iscsilun->zeroblock = g_try_malloc0(iscsilun->block_size);
1145         if (iscsilun->zeroblock == NULL) {
1146             return -ENOMEM;
1147         }
1148     }
1149 
1150     iscsi_co_init_iscsitask(iscsilun, &iTask);
1151 retry:
1152     if (use_16_for_ws) {
1153         iTask.task = iscsi_writesame16_task(iscsilun->iscsi, iscsilun->lun, lba,
1154                                             iscsilun->zeroblock, iscsilun->block_size,
1155                                             nb_blocks, 0, !!(flags & BDRV_REQ_MAY_UNMAP),
1156                                             0, 0, iscsi_co_generic_cb, &iTask);
1157     } else {
1158         iTask.task = iscsi_writesame10_task(iscsilun->iscsi, iscsilun->lun, lba,
1159                                             iscsilun->zeroblock, iscsilun->block_size,
1160                                             nb_blocks, 0, !!(flags & BDRV_REQ_MAY_UNMAP),
1161                                             0, 0, iscsi_co_generic_cb, &iTask);
1162     }
1163     if (iTask.task == NULL) {
1164         return -ENOMEM;
1165     }
1166 
1167     while (!iTask.complete) {
1168         iscsi_set_events(iscsilun);
1169         qemu_coroutine_yield();
1170     }
1171 
1172     if (iTask.status == SCSI_STATUS_CHECK_CONDITION &&
1173         iTask.task->sense.key == SCSI_SENSE_ILLEGAL_REQUEST &&
1174         (iTask.task->sense.ascq == SCSI_SENSE_ASCQ_INVALID_OPERATION_CODE ||
1175          iTask.task->sense.ascq == SCSI_SENSE_ASCQ_INVALID_FIELD_IN_CDB)) {
1176         /* WRITE SAME is not supported by the target */
1177         iscsilun->has_write_same = false;
1178         scsi_free_scsi_task(iTask.task);
1179         return -ENOTSUP;
1180     }
1181 
1182     if (iTask.task != NULL) {
1183         scsi_free_scsi_task(iTask.task);
1184         iTask.task = NULL;
1185     }
1186 
1187     if (iTask.do_retry) {
1188         iTask.complete = 0;
1189         goto retry;
1190     }
1191 
1192     if (iTask.status != SCSI_STATUS_GOOD) {
1193         iscsi_allocmap_set_invalid(iscsilun, offset >> BDRV_SECTOR_BITS,
1194                                    count >> BDRV_SECTOR_BITS);
1195         return iTask.err_code;
1196     }
1197 
1198     if (flags & BDRV_REQ_MAY_UNMAP) {
1199         iscsi_allocmap_set_invalid(iscsilun, offset >> BDRV_SECTOR_BITS,
1200                                    count >> BDRV_SECTOR_BITS);
1201     } else {
1202         iscsi_allocmap_set_allocated(iscsilun, offset >> BDRV_SECTOR_BITS,
1203                                      count >> BDRV_SECTOR_BITS);
1204     }
1205 
1206     return 0;
1207 }
1208 
1209 static void parse_chap(struct iscsi_context *iscsi, const char *target,
1210                        Error **errp)
1211 {
1212     QemuOptsList *list;
1213     QemuOpts *opts;
1214     const char *user = NULL;
1215     const char *password = NULL;
1216     const char *secretid;
1217     char *secret = NULL;
1218 
1219     list = qemu_find_opts("iscsi");
1220     if (!list) {
1221         return;
1222     }
1223 
1224     opts = qemu_opts_find(list, target);
1225     if (opts == NULL) {
1226         opts = QTAILQ_FIRST(&list->head);
1227         if (!opts) {
1228             return;
1229         }
1230     }
1231 
1232     user = qemu_opt_get(opts, "user");
1233     if (!user) {
1234         return;
1235     }
1236 
1237     secretid = qemu_opt_get(opts, "password-secret");
1238     password = qemu_opt_get(opts, "password");
1239     if (secretid && password) {
1240         error_setg(errp, "'password' and 'password-secret' properties are "
1241                    "mutually exclusive");
1242         return;
1243     }
1244     if (secretid) {
1245         secret = qcrypto_secret_lookup_as_utf8(secretid, errp);
1246         if (!secret) {
1247             return;
1248         }
1249         password = secret;
1250     } else if (!password) {
1251         error_setg(errp, "CHAP username specified but no password was given");
1252         return;
1253     }
1254 
1255     if (iscsi_set_initiator_username_pwd(iscsi, user, password)) {
1256         error_setg(errp, "Failed to set initiator username and password");
1257     }
1258 
1259     g_free(secret);
1260 }
1261 
1262 static void parse_header_digest(struct iscsi_context *iscsi, const char *target,
1263                                 Error **errp)
1264 {
1265     QemuOptsList *list;
1266     QemuOpts *opts;
1267     const char *digest = NULL;
1268 
1269     list = qemu_find_opts("iscsi");
1270     if (!list) {
1271         return;
1272     }
1273 
1274     opts = qemu_opts_find(list, target);
1275     if (opts == NULL) {
1276         opts = QTAILQ_FIRST(&list->head);
1277         if (!opts) {
1278             return;
1279         }
1280     }
1281 
1282     digest = qemu_opt_get(opts, "header-digest");
1283     if (!digest) {
1284         return;
1285     }
1286 
1287     if (!strcmp(digest, "CRC32C")) {
1288         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_CRC32C);
1289     } else if (!strcmp(digest, "NONE")) {
1290         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE);
1291     } else if (!strcmp(digest, "CRC32C-NONE")) {
1292         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_CRC32C_NONE);
1293     } else if (!strcmp(digest, "NONE-CRC32C")) {
1294         iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
1295     } else {
1296         error_setg(errp, "Invalid header-digest setting : %s", digest);
1297     }
1298 }
1299 
1300 static char *parse_initiator_name(const char *target)
1301 {
1302     QemuOptsList *list;
1303     QemuOpts *opts;
1304     const char *name;
1305     char *iscsi_name;
1306     UuidInfo *uuid_info;
1307 
1308     list = qemu_find_opts("iscsi");
1309     if (list) {
1310         opts = qemu_opts_find(list, target);
1311         if (!opts) {
1312             opts = QTAILQ_FIRST(&list->head);
1313         }
1314         if (opts) {
1315             name = qemu_opt_get(opts, "initiator-name");
1316             if (name) {
1317                 return g_strdup(name);
1318             }
1319         }
1320     }
1321 
1322     uuid_info = qmp_query_uuid(NULL);
1323     if (strcmp(uuid_info->UUID, UUID_NONE) == 0) {
1324         name = qemu_get_vm_name();
1325     } else {
1326         name = uuid_info->UUID;
1327     }
1328     iscsi_name = g_strdup_printf("iqn.2008-11.org.linux-kvm%s%s",
1329                                  name ? ":" : "", name ? name : "");
1330     qapi_free_UuidInfo(uuid_info);
1331     return iscsi_name;
1332 }
1333 
1334 static int parse_timeout(const char *target)
1335 {
1336     QemuOptsList *list;
1337     QemuOpts *opts;
1338     const char *timeout;
1339 
1340     list = qemu_find_opts("iscsi");
1341     if (list) {
1342         opts = qemu_opts_find(list, target);
1343         if (!opts) {
1344             opts = QTAILQ_FIRST(&list->head);
1345         }
1346         if (opts) {
1347             timeout = qemu_opt_get(opts, "timeout");
1348             if (timeout) {
1349                 return atoi(timeout);
1350             }
1351         }
1352     }
1353 
1354     return 0;
1355 }
1356 
1357 static void iscsi_nop_timed_event(void *opaque)
1358 {
1359     IscsiLun *iscsilun = opaque;
1360 
1361     if (iscsi_get_nops_in_flight(iscsilun->iscsi) >= MAX_NOP_FAILURES) {
1362         error_report("iSCSI: NOP timeout. Reconnecting...");
1363         iscsilun->request_timed_out = true;
1364     } else if (iscsi_nop_out_async(iscsilun->iscsi, NULL, NULL, 0, NULL) != 0) {
1365         error_report("iSCSI: failed to sent NOP-Out. Disabling NOP messages.");
1366         return;
1367     }
1368 
1369     timer_mod(iscsilun->nop_timer, qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + NOP_INTERVAL);
1370     iscsi_set_events(iscsilun);
1371 }
1372 
1373 static void iscsi_readcapacity_sync(IscsiLun *iscsilun, Error **errp)
1374 {
1375     struct scsi_task *task = NULL;
1376     struct scsi_readcapacity10 *rc10 = NULL;
1377     struct scsi_readcapacity16 *rc16 = NULL;
1378     int retries = ISCSI_CMD_RETRIES;
1379 
1380     do {
1381         if (task != NULL) {
1382             scsi_free_scsi_task(task);
1383             task = NULL;
1384         }
1385 
1386         switch (iscsilun->type) {
1387         case TYPE_DISK:
1388             task = iscsi_readcapacity16_sync(iscsilun->iscsi, iscsilun->lun);
1389             if (task != NULL && task->status == SCSI_STATUS_GOOD) {
1390                 rc16 = scsi_datain_unmarshall(task);
1391                 if (rc16 == NULL) {
1392                     error_setg(errp, "iSCSI: Failed to unmarshall readcapacity16 data.");
1393                 } else {
1394                     iscsilun->block_size = rc16->block_length;
1395                     iscsilun->num_blocks = rc16->returned_lba + 1;
1396                     iscsilun->lbpme = !!rc16->lbpme;
1397                     iscsilun->lbprz = !!rc16->lbprz;
1398                     iscsilun->use_16_for_rw = (rc16->returned_lba > 0xffffffff);
1399                 }
1400                 break;
1401             }
1402             if (task != NULL && task->status == SCSI_STATUS_CHECK_CONDITION
1403                 && task->sense.key == SCSI_SENSE_UNIT_ATTENTION) {
1404                 break;
1405             }
1406             /* Fall through and try READ CAPACITY(10) instead.  */
1407         case TYPE_ROM:
1408             task = iscsi_readcapacity10_sync(iscsilun->iscsi, iscsilun->lun, 0, 0);
1409             if (task != NULL && task->status == SCSI_STATUS_GOOD) {
1410                 rc10 = scsi_datain_unmarshall(task);
1411                 if (rc10 == NULL) {
1412                     error_setg(errp, "iSCSI: Failed to unmarshall readcapacity10 data.");
1413                 } else {
1414                     iscsilun->block_size = rc10->block_size;
1415                     if (rc10->lba == 0) {
1416                         /* blank disk loaded */
1417                         iscsilun->num_blocks = 0;
1418                     } else {
1419                         iscsilun->num_blocks = rc10->lba + 1;
1420                     }
1421                 }
1422             }
1423             break;
1424         default:
1425             return;
1426         }
1427     } while (task != NULL && task->status == SCSI_STATUS_CHECK_CONDITION
1428              && task->sense.key == SCSI_SENSE_UNIT_ATTENTION
1429              && retries-- > 0);
1430 
1431     if (task == NULL || task->status != SCSI_STATUS_GOOD) {
1432         error_setg(errp, "iSCSI: failed to send readcapacity10/16 command");
1433     } else if (!iscsilun->block_size ||
1434                iscsilun->block_size % BDRV_SECTOR_SIZE) {
1435         error_setg(errp, "iSCSI: the target returned an invalid "
1436                    "block size of %d.", iscsilun->block_size);
1437     }
1438     if (task) {
1439         scsi_free_scsi_task(task);
1440     }
1441 }
1442 
1443 /* TODO Convert to fine grained options */
1444 static QemuOptsList runtime_opts = {
1445     .name = "iscsi",
1446     .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
1447     .desc = {
1448         {
1449             .name = "filename",
1450             .type = QEMU_OPT_STRING,
1451             .help = "URL to the iscsi image",
1452         },
1453         { /* end of list */ }
1454     },
1455 };
1456 
1457 static struct scsi_task *iscsi_do_inquiry(struct iscsi_context *iscsi, int lun,
1458                                           int evpd, int pc, void **inq, Error **errp)
1459 {
1460     int full_size;
1461     struct scsi_task *task = NULL;
1462     task = iscsi_inquiry_sync(iscsi, lun, evpd, pc, 64);
1463     if (task == NULL || task->status != SCSI_STATUS_GOOD) {
1464         goto fail;
1465     }
1466     full_size = scsi_datain_getfullsize(task);
1467     if (full_size > task->datain.size) {
1468         scsi_free_scsi_task(task);
1469 
1470         /* we need more data for the full list */
1471         task = iscsi_inquiry_sync(iscsi, lun, evpd, pc, full_size);
1472         if (task == NULL || task->status != SCSI_STATUS_GOOD) {
1473             goto fail;
1474         }
1475     }
1476 
1477     *inq = scsi_datain_unmarshall(task);
1478     if (*inq == NULL) {
1479         error_setg(errp, "iSCSI: failed to unmarshall inquiry datain blob");
1480         goto fail_with_err;
1481     }
1482 
1483     return task;
1484 
1485 fail:
1486     error_setg(errp, "iSCSI: Inquiry command failed : %s",
1487                iscsi_get_error(iscsi));
1488 fail_with_err:
1489     if (task != NULL) {
1490         scsi_free_scsi_task(task);
1491     }
1492     return NULL;
1493 }
1494 
1495 static void iscsi_detach_aio_context(BlockDriverState *bs)
1496 {
1497     IscsiLun *iscsilun = bs->opaque;
1498 
1499     aio_set_fd_handler(iscsilun->aio_context, iscsi_get_fd(iscsilun->iscsi),
1500                        false, NULL, NULL, NULL);
1501     iscsilun->events = 0;
1502 
1503     if (iscsilun->nop_timer) {
1504         timer_del(iscsilun->nop_timer);
1505         timer_free(iscsilun->nop_timer);
1506         iscsilun->nop_timer = NULL;
1507     }
1508     if (iscsilun->event_timer) {
1509         timer_del(iscsilun->event_timer);
1510         timer_free(iscsilun->event_timer);
1511         iscsilun->event_timer = NULL;
1512     }
1513 }
1514 
1515 static void iscsi_attach_aio_context(BlockDriverState *bs,
1516                                      AioContext *new_context)
1517 {
1518     IscsiLun *iscsilun = bs->opaque;
1519 
1520     iscsilun->aio_context = new_context;
1521     iscsi_set_events(iscsilun);
1522 
1523     /* Set up a timer for sending out iSCSI NOPs */
1524     iscsilun->nop_timer = aio_timer_new(iscsilun->aio_context,
1525                                         QEMU_CLOCK_REALTIME, SCALE_MS,
1526                                         iscsi_nop_timed_event, iscsilun);
1527     timer_mod(iscsilun->nop_timer,
1528               qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + NOP_INTERVAL);
1529 
1530     /* Set up a timer for periodic calls to iscsi_set_events and to
1531      * scan for command timeout */
1532     iscsilun->event_timer = aio_timer_new(iscsilun->aio_context,
1533                                           QEMU_CLOCK_REALTIME, SCALE_MS,
1534                                           iscsi_timed_check_events, iscsilun);
1535     timer_mod(iscsilun->event_timer,
1536               qemu_clock_get_ms(QEMU_CLOCK_REALTIME) + EVENT_INTERVAL);
1537 }
1538 
1539 static void iscsi_modesense_sync(IscsiLun *iscsilun)
1540 {
1541     struct scsi_task *task;
1542     struct scsi_mode_sense *ms = NULL;
1543     iscsilun->write_protected = false;
1544     iscsilun->dpofua = false;
1545 
1546     task = iscsi_modesense6_sync(iscsilun->iscsi, iscsilun->lun,
1547                                  1, SCSI_MODESENSE_PC_CURRENT,
1548                                  0x3F, 0, 255);
1549     if (task == NULL) {
1550         error_report("iSCSI: Failed to send MODE_SENSE(6) command: %s",
1551                      iscsi_get_error(iscsilun->iscsi));
1552         goto out;
1553     }
1554 
1555     if (task->status != SCSI_STATUS_GOOD) {
1556         error_report("iSCSI: Failed MODE_SENSE(6), LUN assumed writable");
1557         goto out;
1558     }
1559     ms = scsi_datain_unmarshall(task);
1560     if (!ms) {
1561         error_report("iSCSI: Failed to unmarshall MODE_SENSE(6) data: %s",
1562                      iscsi_get_error(iscsilun->iscsi));
1563         goto out;
1564     }
1565     iscsilun->write_protected = ms->device_specific_parameter & 0x80;
1566     iscsilun->dpofua          = ms->device_specific_parameter & 0x10;
1567 
1568 out:
1569     if (task) {
1570         scsi_free_scsi_task(task);
1571     }
1572 }
1573 
1574 /*
1575  * We support iscsi url's on the form
1576  * iscsi://[<username>%<password>@]<host>[:<port>]/<targetname>/<lun>
1577  */
1578 static int iscsi_open(BlockDriverState *bs, QDict *options, int flags,
1579                       Error **errp)
1580 {
1581     IscsiLun *iscsilun = bs->opaque;
1582     struct iscsi_context *iscsi = NULL;
1583     struct iscsi_url *iscsi_url = NULL;
1584     struct scsi_task *task = NULL;
1585     struct scsi_inquiry_standard *inq = NULL;
1586     struct scsi_inquiry_supported_pages *inq_vpd;
1587     char *initiator_name = NULL;
1588     QemuOpts *opts;
1589     Error *local_err = NULL;
1590     const char *filename;
1591     int i, ret = 0, timeout = 0;
1592 
1593     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
1594     qemu_opts_absorb_qdict(opts, options, &local_err);
1595     if (local_err) {
1596         error_propagate(errp, local_err);
1597         ret = -EINVAL;
1598         goto out;
1599     }
1600 
1601     filename = qemu_opt_get(opts, "filename");
1602 
1603     iscsi_url = iscsi_parse_full_url(iscsi, filename);
1604     if (iscsi_url == NULL) {
1605         error_setg(errp, "Failed to parse URL : %s", filename);
1606         ret = -EINVAL;
1607         goto out;
1608     }
1609 
1610     memset(iscsilun, 0, sizeof(IscsiLun));
1611 
1612     initiator_name = parse_initiator_name(iscsi_url->target);
1613 
1614     iscsi = iscsi_create_context(initiator_name);
1615     if (iscsi == NULL) {
1616         error_setg(errp, "iSCSI: Failed to create iSCSI context.");
1617         ret = -ENOMEM;
1618         goto out;
1619     }
1620 
1621     if (iscsi_set_targetname(iscsi, iscsi_url->target)) {
1622         error_setg(errp, "iSCSI: Failed to set target name.");
1623         ret = -EINVAL;
1624         goto out;
1625     }
1626 
1627     if (iscsi_url->user[0] != '\0') {
1628         ret = iscsi_set_initiator_username_pwd(iscsi, iscsi_url->user,
1629                                               iscsi_url->passwd);
1630         if (ret != 0) {
1631             error_setg(errp, "Failed to set initiator username and password");
1632             ret = -EINVAL;
1633             goto out;
1634         }
1635     }
1636 
1637     /* check if we got CHAP username/password via the options */
1638     parse_chap(iscsi, iscsi_url->target, &local_err);
1639     if (local_err != NULL) {
1640         error_propagate(errp, local_err);
1641         ret = -EINVAL;
1642         goto out;
1643     }
1644 
1645     if (iscsi_set_session_type(iscsi, ISCSI_SESSION_NORMAL) != 0) {
1646         error_setg(errp, "iSCSI: Failed to set session type to normal.");
1647         ret = -EINVAL;
1648         goto out;
1649     }
1650 
1651     iscsi_set_header_digest(iscsi, ISCSI_HEADER_DIGEST_NONE_CRC32C);
1652 
1653     /* check if we got HEADER_DIGEST via the options */
1654     parse_header_digest(iscsi, iscsi_url->target, &local_err);
1655     if (local_err != NULL) {
1656         error_propagate(errp, local_err);
1657         ret = -EINVAL;
1658         goto out;
1659     }
1660 
1661     /* timeout handling is broken in libiscsi before 1.15.0 */
1662     timeout = parse_timeout(iscsi_url->target);
1663 #if defined(LIBISCSI_API_VERSION) && LIBISCSI_API_VERSION >= 20150621
1664     iscsi_set_timeout(iscsi, timeout);
1665 #else
1666     if (timeout) {
1667         error_report("iSCSI: ignoring timeout value for libiscsi <1.15.0");
1668     }
1669 #endif
1670 
1671     if (iscsi_full_connect_sync(iscsi, iscsi_url->portal, iscsi_url->lun) != 0) {
1672         error_setg(errp, "iSCSI: Failed to connect to LUN : %s",
1673             iscsi_get_error(iscsi));
1674         ret = -EINVAL;
1675         goto out;
1676     }
1677 
1678     iscsilun->iscsi = iscsi;
1679     iscsilun->aio_context = bdrv_get_aio_context(bs);
1680     iscsilun->lun   = iscsi_url->lun;
1681     iscsilun->has_write_same = true;
1682 
1683     task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 0, 0,
1684                             (void **) &inq, errp);
1685     if (task == NULL) {
1686         ret = -EINVAL;
1687         goto out;
1688     }
1689     iscsilun->type = inq->periperal_device_type;
1690     scsi_free_scsi_task(task);
1691     task = NULL;
1692 
1693     iscsi_modesense_sync(iscsilun);
1694     if (iscsilun->dpofua) {
1695         bs->supported_write_flags = BDRV_REQ_FUA;
1696     }
1697     bs->supported_zero_flags = BDRV_REQ_MAY_UNMAP;
1698 
1699     /* Check the write protect flag of the LUN if we want to write */
1700     if (iscsilun->type == TYPE_DISK && (flags & BDRV_O_RDWR) &&
1701         iscsilun->write_protected) {
1702         error_setg(errp, "Cannot open a write protected LUN as read-write");
1703         ret = -EACCES;
1704         goto out;
1705     }
1706 
1707     iscsi_readcapacity_sync(iscsilun, &local_err);
1708     if (local_err != NULL) {
1709         error_propagate(errp, local_err);
1710         ret = -EINVAL;
1711         goto out;
1712     }
1713     bs->total_sectors = sector_lun2qemu(iscsilun->num_blocks, iscsilun);
1714 
1715     /* We don't have any emulation for devices other than disks and CD-ROMs, so
1716      * this must be sg ioctl compatible. We force it to be sg, otherwise qemu
1717      * will try to read from the device to guess the image format.
1718      */
1719     if (iscsilun->type != TYPE_DISK && iscsilun->type != TYPE_ROM) {
1720         bs->sg = true;
1721     }
1722 
1723     task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 1,
1724                             SCSI_INQUIRY_PAGECODE_SUPPORTED_VPD_PAGES,
1725                             (void **) &inq_vpd, errp);
1726     if (task == NULL) {
1727         ret = -EINVAL;
1728         goto out;
1729     }
1730     for (i = 0; i < inq_vpd->num_pages; i++) {
1731         struct scsi_task *inq_task;
1732         struct scsi_inquiry_logical_block_provisioning *inq_lbp;
1733         struct scsi_inquiry_block_limits *inq_bl;
1734         switch (inq_vpd->pages[i]) {
1735         case SCSI_INQUIRY_PAGECODE_LOGICAL_BLOCK_PROVISIONING:
1736             inq_task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 1,
1737                                         SCSI_INQUIRY_PAGECODE_LOGICAL_BLOCK_PROVISIONING,
1738                                         (void **) &inq_lbp, errp);
1739             if (inq_task == NULL) {
1740                 ret = -EINVAL;
1741                 goto out;
1742             }
1743             memcpy(&iscsilun->lbp, inq_lbp,
1744                    sizeof(struct scsi_inquiry_logical_block_provisioning));
1745             scsi_free_scsi_task(inq_task);
1746             break;
1747         case SCSI_INQUIRY_PAGECODE_BLOCK_LIMITS:
1748             inq_task = iscsi_do_inquiry(iscsilun->iscsi, iscsilun->lun, 1,
1749                                     SCSI_INQUIRY_PAGECODE_BLOCK_LIMITS,
1750                                     (void **) &inq_bl, errp);
1751             if (inq_task == NULL) {
1752                 ret = -EINVAL;
1753                 goto out;
1754             }
1755             memcpy(&iscsilun->bl, inq_bl,
1756                    sizeof(struct scsi_inquiry_block_limits));
1757             scsi_free_scsi_task(inq_task);
1758             break;
1759         default:
1760             break;
1761         }
1762     }
1763     scsi_free_scsi_task(task);
1764     task = NULL;
1765 
1766     iscsi_attach_aio_context(bs, iscsilun->aio_context);
1767 
1768     /* Guess the internal cluster (page) size of the iscsi target by the means
1769      * of opt_unmap_gran. Transfer the unmap granularity only if it has a
1770      * reasonable size */
1771     if (iscsilun->bl.opt_unmap_gran * iscsilun->block_size >= 4 * 1024 &&
1772         iscsilun->bl.opt_unmap_gran * iscsilun->block_size <= 16 * 1024 * 1024) {
1773         iscsilun->cluster_sectors = (iscsilun->bl.opt_unmap_gran *
1774                                      iscsilun->block_size) >> BDRV_SECTOR_BITS;
1775         if (iscsilun->lbprz) {
1776             ret = iscsi_allocmap_init(iscsilun, bs->open_flags);
1777         }
1778     }
1779 
1780 out:
1781     qemu_opts_del(opts);
1782     g_free(initiator_name);
1783     if (iscsi_url != NULL) {
1784         iscsi_destroy_url(iscsi_url);
1785     }
1786     if (task != NULL) {
1787         scsi_free_scsi_task(task);
1788     }
1789 
1790     if (ret) {
1791         if (iscsi != NULL) {
1792             if (iscsi_is_logged_in(iscsi)) {
1793                 iscsi_logout_sync(iscsi);
1794             }
1795             iscsi_destroy_context(iscsi);
1796         }
1797         memset(iscsilun, 0, sizeof(IscsiLun));
1798     }
1799     return ret;
1800 }
1801 
1802 static void iscsi_close(BlockDriverState *bs)
1803 {
1804     IscsiLun *iscsilun = bs->opaque;
1805     struct iscsi_context *iscsi = iscsilun->iscsi;
1806 
1807     iscsi_detach_aio_context(bs);
1808     if (iscsi_is_logged_in(iscsi)) {
1809         iscsi_logout_sync(iscsi);
1810     }
1811     iscsi_destroy_context(iscsi);
1812     g_free(iscsilun->zeroblock);
1813     iscsi_allocmap_free(iscsilun);
1814     memset(iscsilun, 0, sizeof(IscsiLun));
1815 }
1816 
1817 static void iscsi_refresh_limits(BlockDriverState *bs, Error **errp)
1818 {
1819     /* We don't actually refresh here, but just return data queried in
1820      * iscsi_open(): iscsi targets don't change their limits. */
1821 
1822     IscsiLun *iscsilun = bs->opaque;
1823     uint64_t max_xfer_len = iscsilun->use_16_for_rw ? 0xffffffff : 0xffff;
1824 
1825     bs->bl.request_alignment = iscsilun->block_size;
1826 
1827     if (iscsilun->bl.max_xfer_len) {
1828         max_xfer_len = MIN(max_xfer_len, iscsilun->bl.max_xfer_len);
1829     }
1830 
1831     if (max_xfer_len * iscsilun->block_size < INT_MAX) {
1832         bs->bl.max_transfer = max_xfer_len * iscsilun->block_size;
1833     }
1834 
1835     if (iscsilun->lbp.lbpu) {
1836         if (iscsilun->bl.max_unmap < 0xffffffff / iscsilun->block_size) {
1837             bs->bl.max_pdiscard =
1838                 iscsilun->bl.max_unmap * iscsilun->block_size;
1839         }
1840         bs->bl.pdiscard_alignment =
1841             iscsilun->bl.opt_unmap_gran * iscsilun->block_size;
1842     } else {
1843         bs->bl.pdiscard_alignment = iscsilun->block_size;
1844     }
1845 
1846     if (iscsilun->bl.max_ws_len < 0xffffffff / iscsilun->block_size) {
1847         bs->bl.max_pwrite_zeroes =
1848             iscsilun->bl.max_ws_len * iscsilun->block_size;
1849     }
1850     if (iscsilun->lbp.lbpws) {
1851         bs->bl.pwrite_zeroes_alignment =
1852             iscsilun->bl.opt_unmap_gran * iscsilun->block_size;
1853     } else {
1854         bs->bl.pwrite_zeroes_alignment = iscsilun->block_size;
1855     }
1856     if (iscsilun->bl.opt_xfer_len &&
1857         iscsilun->bl.opt_xfer_len < INT_MAX / iscsilun->block_size) {
1858         bs->bl.opt_transfer = pow2floor(iscsilun->bl.opt_xfer_len *
1859                                         iscsilun->block_size);
1860     }
1861 }
1862 
1863 /* Note that this will not re-establish a connection with an iSCSI target - it
1864  * is effectively a NOP.  */
1865 static int iscsi_reopen_prepare(BDRVReopenState *state,
1866                                 BlockReopenQueue *queue, Error **errp)
1867 {
1868     IscsiLun *iscsilun = state->bs->opaque;
1869 
1870     if (state->flags & BDRV_O_RDWR && iscsilun->write_protected) {
1871         error_setg(errp, "Cannot open a write protected LUN as read-write");
1872         return -EACCES;
1873     }
1874     return 0;
1875 }
1876 
1877 static void iscsi_reopen_commit(BDRVReopenState *reopen_state)
1878 {
1879     IscsiLun *iscsilun = reopen_state->bs->opaque;
1880 
1881     /* the cache.direct status might have changed */
1882     if (iscsilun->allocmap != NULL) {
1883         iscsi_allocmap_init(iscsilun, reopen_state->flags);
1884     }
1885 }
1886 
1887 static int iscsi_truncate(BlockDriverState *bs, int64_t offset)
1888 {
1889     IscsiLun *iscsilun = bs->opaque;
1890     Error *local_err = NULL;
1891 
1892     if (iscsilun->type != TYPE_DISK) {
1893         return -ENOTSUP;
1894     }
1895 
1896     iscsi_readcapacity_sync(iscsilun, &local_err);
1897     if (local_err != NULL) {
1898         error_free(local_err);
1899         return -EIO;
1900     }
1901 
1902     if (offset > iscsi_getlength(bs)) {
1903         return -EINVAL;
1904     }
1905 
1906     if (iscsilun->allocmap != NULL) {
1907         iscsi_allocmap_init(iscsilun, bs->open_flags);
1908     }
1909 
1910     return 0;
1911 }
1912 
1913 static int iscsi_create(const char *filename, QemuOpts *opts, Error **errp)
1914 {
1915     int ret = 0;
1916     int64_t total_size = 0;
1917     BlockDriverState *bs;
1918     IscsiLun *iscsilun = NULL;
1919     QDict *bs_options;
1920 
1921     bs = bdrv_new();
1922 
1923     /* Read out options */
1924     total_size = DIV_ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
1925                               BDRV_SECTOR_SIZE);
1926     bs->opaque = g_new0(struct IscsiLun, 1);
1927     iscsilun = bs->opaque;
1928 
1929     bs_options = qdict_new();
1930     qdict_put(bs_options, "filename", qstring_from_str(filename));
1931     ret = iscsi_open(bs, bs_options, 0, NULL);
1932     QDECREF(bs_options);
1933 
1934     if (ret != 0) {
1935         goto out;
1936     }
1937     iscsi_detach_aio_context(bs);
1938     if (iscsilun->type != TYPE_DISK) {
1939         ret = -ENODEV;
1940         goto out;
1941     }
1942     if (bs->total_sectors < total_size) {
1943         ret = -ENOSPC;
1944         goto out;
1945     }
1946 
1947     ret = 0;
1948 out:
1949     if (iscsilun->iscsi != NULL) {
1950         iscsi_destroy_context(iscsilun->iscsi);
1951     }
1952     g_free(bs->opaque);
1953     bs->opaque = NULL;
1954     bdrv_unref(bs);
1955     return ret;
1956 }
1957 
1958 static int iscsi_get_info(BlockDriverState *bs, BlockDriverInfo *bdi)
1959 {
1960     IscsiLun *iscsilun = bs->opaque;
1961     bdi->unallocated_blocks_are_zero = iscsilun->lbprz;
1962     bdi->can_write_zeroes_with_unmap = iscsilun->lbprz && iscsilun->lbp.lbpws;
1963     bdi->cluster_size = iscsilun->cluster_sectors * BDRV_SECTOR_SIZE;
1964     return 0;
1965 }
1966 
1967 static void iscsi_invalidate_cache(BlockDriverState *bs,
1968                                    Error **errp)
1969 {
1970     IscsiLun *iscsilun = bs->opaque;
1971     iscsi_allocmap_invalidate(iscsilun);
1972 }
1973 
1974 static QemuOptsList iscsi_create_opts = {
1975     .name = "iscsi-create-opts",
1976     .head = QTAILQ_HEAD_INITIALIZER(iscsi_create_opts.head),
1977     .desc = {
1978         {
1979             .name = BLOCK_OPT_SIZE,
1980             .type = QEMU_OPT_SIZE,
1981             .help = "Virtual disk size"
1982         },
1983         { /* end of list */ }
1984     }
1985 };
1986 
1987 static BlockDriver bdrv_iscsi = {
1988     .format_name     = "iscsi",
1989     .protocol_name   = "iscsi",
1990 
1991     .instance_size   = sizeof(IscsiLun),
1992     .bdrv_needs_filename = true,
1993     .bdrv_file_open  = iscsi_open,
1994     .bdrv_close      = iscsi_close,
1995     .bdrv_create     = iscsi_create,
1996     .create_opts     = &iscsi_create_opts,
1997     .bdrv_reopen_prepare   = iscsi_reopen_prepare,
1998     .bdrv_reopen_commit    = iscsi_reopen_commit,
1999     .bdrv_invalidate_cache = iscsi_invalidate_cache,
2000 
2001     .bdrv_getlength  = iscsi_getlength,
2002     .bdrv_get_info   = iscsi_get_info,
2003     .bdrv_truncate   = iscsi_truncate,
2004     .bdrv_refresh_limits = iscsi_refresh_limits,
2005 
2006     .bdrv_co_get_block_status = iscsi_co_get_block_status,
2007     .bdrv_co_discard      = iscsi_co_discard,
2008     .bdrv_co_pwrite_zeroes = iscsi_co_pwrite_zeroes,
2009     .bdrv_co_readv         = iscsi_co_readv,
2010     .bdrv_co_writev_flags  = iscsi_co_writev_flags,
2011     .bdrv_co_flush_to_disk = iscsi_co_flush,
2012 
2013 #ifdef __linux__
2014     .bdrv_aio_ioctl   = iscsi_aio_ioctl,
2015 #endif
2016 
2017     .bdrv_detach_aio_context = iscsi_detach_aio_context,
2018     .bdrv_attach_aio_context = iscsi_attach_aio_context,
2019 };
2020 
2021 static QemuOptsList qemu_iscsi_opts = {
2022     .name = "iscsi",
2023     .head = QTAILQ_HEAD_INITIALIZER(qemu_iscsi_opts.head),
2024     .desc = {
2025         {
2026             .name = "user",
2027             .type = QEMU_OPT_STRING,
2028             .help = "username for CHAP authentication to target",
2029         },{
2030             .name = "password",
2031             .type = QEMU_OPT_STRING,
2032             .help = "password for CHAP authentication to target",
2033         },{
2034             .name = "password-secret",
2035             .type = QEMU_OPT_STRING,
2036             .help = "ID of the secret providing password for CHAP "
2037                     "authentication to target",
2038         },{
2039             .name = "header-digest",
2040             .type = QEMU_OPT_STRING,
2041             .help = "HeaderDigest setting. "
2042                     "{CRC32C|CRC32C-NONE|NONE-CRC32C|NONE}",
2043         },{
2044             .name = "initiator-name",
2045             .type = QEMU_OPT_STRING,
2046             .help = "Initiator iqn name to use when connecting",
2047         },{
2048             .name = "timeout",
2049             .type = QEMU_OPT_NUMBER,
2050             .help = "Request timeout in seconds (default 0 = no timeout)",
2051         },
2052         { /* end of list */ }
2053     },
2054 };
2055 
2056 static void iscsi_block_init(void)
2057 {
2058     bdrv_register(&bdrv_iscsi);
2059     qemu_add_opts(&qemu_iscsi_opts);
2060 }
2061 
2062 block_init(iscsi_block_init);
2063