xref: /openbmc/qemu/block/rbd.c (revision a495eba0)
1 /*
2  * QEMU Block driver for RADOS (Ceph)
3  *
4  * Copyright (C) 2010-2011 Christian Brunner <chb@muc.de>,
5  *                         Josh Durgin <josh.durgin@dreamhost.com>
6  *
7  * This work is licensed under the terms of the GNU GPL, version 2.  See
8  * the COPYING file in the top-level directory.
9  *
10  * Contributions after 2012-01-13 are licensed under the terms of the
11  * GNU GPL, version 2 or (at your option) any later version.
12  */
13 
14 #include "qemu/osdep.h"
15 
16 #include <rbd/librbd.h>
17 #include "qapi/error.h"
18 #include "qemu/error-report.h"
19 #include "qemu/module.h"
20 #include "qemu/option.h"
21 #include "block/block_int.h"
22 #include "block/qdict.h"
23 #include "crypto/secret.h"
24 #include "qemu/cutils.h"
25 #include "sysemu/replay.h"
26 #include "qapi/qmp/qstring.h"
27 #include "qapi/qmp/qdict.h"
28 #include "qapi/qmp/qjson.h"
29 #include "qapi/qmp/qlist.h"
30 #include "qapi/qobject-input-visitor.h"
31 #include "qapi/qapi-visit-block-core.h"
32 
33 /*
34  * When specifying the image filename use:
35  *
36  * rbd:poolname/devicename[@snapshotname][:option1=value1[:option2=value2...]]
37  *
38  * poolname must be the name of an existing rados pool.
39  *
40  * devicename is the name of the rbd image.
41  *
42  * Each option given is used to configure rados, and may be any valid
43  * Ceph option, "id", or "conf".
44  *
45  * The "id" option indicates what user we should authenticate as to
46  * the Ceph cluster.  If it is excluded we will use the Ceph default
47  * (normally 'admin').
48  *
49  * The "conf" option specifies a Ceph configuration file to read.  If
50  * it is not specified, we will read from the default Ceph locations
51  * (e.g., /etc/ceph/ceph.conf).  To avoid reading _any_ configuration
52  * file, specify conf=/dev/null.
53  *
54  * Configuration values containing :, @, or = can be escaped with a
55  * leading "\".
56  */
57 
58 #define OBJ_MAX_SIZE (1UL << OBJ_DEFAULT_OBJ_ORDER)
59 
60 #define RBD_MAX_SNAPS 100
61 
62 #define RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN 8
63 
64 static const char rbd_luks_header_verification[
65         RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN] = {
66     'L', 'U', 'K', 'S', 0xBA, 0xBE, 0, 1
67 };
68 
69 static const char rbd_luks2_header_verification[
70         RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN] = {
71     'L', 'U', 'K', 'S', 0xBA, 0xBE, 0, 2
72 };
73 
74 typedef enum {
75     RBD_AIO_READ,
76     RBD_AIO_WRITE,
77     RBD_AIO_DISCARD,
78     RBD_AIO_FLUSH,
79     RBD_AIO_WRITE_ZEROES
80 } RBDAIOCmd;
81 
82 typedef struct BDRVRBDState {
83     rados_t cluster;
84     rados_ioctx_t io_ctx;
85     rbd_image_t image;
86     char *image_name;
87     char *snap;
88     char *namespace;
89     uint64_t image_size;
90     uint64_t object_size;
91 } BDRVRBDState;
92 
93 typedef struct RBDTask {
94     BlockDriverState *bs;
95     Coroutine *co;
96     bool complete;
97     int64_t ret;
98 } RBDTask;
99 
100 typedef struct RBDDiffIterateReq {
101     uint64_t offs;
102     uint64_t bytes;
103     bool exists;
104 } RBDDiffIterateReq;
105 
106 static int qemu_rbd_connect(rados_t *cluster, rados_ioctx_t *io_ctx,
107                             BlockdevOptionsRbd *opts, bool cache,
108                             const char *keypairs, const char *secretid,
109                             Error **errp);
110 
111 static char *qemu_rbd_strchr(char *src, char delim)
112 {
113     char *p;
114 
115     for (p = src; *p; ++p) {
116         if (*p == delim) {
117             return p;
118         }
119         if (*p == '\\' && p[1] != '\0') {
120             ++p;
121         }
122     }
123 
124     return NULL;
125 }
126 
127 
128 static char *qemu_rbd_next_tok(char *src, char delim, char **p)
129 {
130     char *end;
131 
132     *p = NULL;
133 
134     end = qemu_rbd_strchr(src, delim);
135     if (end) {
136         *p = end + 1;
137         *end = '\0';
138     }
139     return src;
140 }
141 
142 static void qemu_rbd_unescape(char *src)
143 {
144     char *p;
145 
146     for (p = src; *src; ++src, ++p) {
147         if (*src == '\\' && src[1] != '\0') {
148             src++;
149         }
150         *p = *src;
151     }
152     *p = '\0';
153 }
154 
155 static void qemu_rbd_parse_filename(const char *filename, QDict *options,
156                                     Error **errp)
157 {
158     const char *start;
159     char *p, *buf;
160     QList *keypairs = NULL;
161     char *found_str, *image_name;
162 
163     if (!strstart(filename, "rbd:", &start)) {
164         error_setg(errp, "File name must start with 'rbd:'");
165         return;
166     }
167 
168     buf = g_strdup(start);
169     p = buf;
170 
171     found_str = qemu_rbd_next_tok(p, '/', &p);
172     if (!p) {
173         error_setg(errp, "Pool name is required");
174         goto done;
175     }
176     qemu_rbd_unescape(found_str);
177     qdict_put_str(options, "pool", found_str);
178 
179     if (qemu_rbd_strchr(p, '@')) {
180         image_name = qemu_rbd_next_tok(p, '@', &p);
181 
182         found_str = qemu_rbd_next_tok(p, ':', &p);
183         qemu_rbd_unescape(found_str);
184         qdict_put_str(options, "snapshot", found_str);
185     } else {
186         image_name = qemu_rbd_next_tok(p, ':', &p);
187     }
188     /* Check for namespace in the image_name */
189     if (qemu_rbd_strchr(image_name, '/')) {
190         found_str = qemu_rbd_next_tok(image_name, '/', &image_name);
191         qemu_rbd_unescape(found_str);
192         qdict_put_str(options, "namespace", found_str);
193     } else {
194         qdict_put_str(options, "namespace", "");
195     }
196     qemu_rbd_unescape(image_name);
197     qdict_put_str(options, "image", image_name);
198     if (!p) {
199         goto done;
200     }
201 
202     /* The following are essentially all key/value pairs, and we treat
203      * 'id' and 'conf' a bit special.  Key/value pairs may be in any order. */
204     while (p) {
205         char *name, *value;
206         name = qemu_rbd_next_tok(p, '=', &p);
207         if (!p) {
208             error_setg(errp, "conf option %s has no value", name);
209             break;
210         }
211 
212         qemu_rbd_unescape(name);
213 
214         value = qemu_rbd_next_tok(p, ':', &p);
215         qemu_rbd_unescape(value);
216 
217         if (!strcmp(name, "conf")) {
218             qdict_put_str(options, "conf", value);
219         } else if (!strcmp(name, "id")) {
220             qdict_put_str(options, "user", value);
221         } else {
222             /*
223              * We pass these internally to qemu_rbd_set_keypairs(), so
224              * we can get away with the simpler list of [ "key1",
225              * "value1", "key2", "value2" ] rather than a raw dict
226              * { "key1": "value1", "key2": "value2" } where we can't
227              * guarantee order, or even a more correct but complex
228              * [ { "key1": "value1" }, { "key2": "value2" } ]
229              */
230             if (!keypairs) {
231                 keypairs = qlist_new();
232             }
233             qlist_append_str(keypairs, name);
234             qlist_append_str(keypairs, value);
235         }
236     }
237 
238     if (keypairs) {
239         qdict_put(options, "=keyvalue-pairs",
240                   qstring_from_gstring(qobject_to_json(QOBJECT(keypairs))));
241     }
242 
243 done:
244     g_free(buf);
245     qobject_unref(keypairs);
246     return;
247 }
248 
249 static int qemu_rbd_set_auth(rados_t cluster, BlockdevOptionsRbd *opts,
250                              Error **errp)
251 {
252     char *key, *acr;
253     int r;
254     GString *accu;
255     RbdAuthModeList *auth;
256 
257     if (opts->key_secret) {
258         key = qcrypto_secret_lookup_as_base64(opts->key_secret, errp);
259         if (!key) {
260             return -EIO;
261         }
262         r = rados_conf_set(cluster, "key", key);
263         g_free(key);
264         if (r < 0) {
265             error_setg_errno(errp, -r, "Could not set 'key'");
266             return r;
267         }
268     }
269 
270     if (opts->has_auth_client_required) {
271         accu = g_string_new("");
272         for (auth = opts->auth_client_required; auth; auth = auth->next) {
273             if (accu->str[0]) {
274                 g_string_append_c(accu, ';');
275             }
276             g_string_append(accu, RbdAuthMode_str(auth->value));
277         }
278         acr = g_string_free(accu, FALSE);
279         r = rados_conf_set(cluster, "auth_client_required", acr);
280         g_free(acr);
281         if (r < 0) {
282             error_setg_errno(errp, -r,
283                              "Could not set 'auth_client_required'");
284             return r;
285         }
286     }
287 
288     return 0;
289 }
290 
291 static int qemu_rbd_set_keypairs(rados_t cluster, const char *keypairs_json,
292                                  Error **errp)
293 {
294     QList *keypairs;
295     QString *name;
296     QString *value;
297     const char *key;
298     size_t remaining;
299     int ret = 0;
300 
301     if (!keypairs_json) {
302         return ret;
303     }
304     keypairs = qobject_to(QList,
305                           qobject_from_json(keypairs_json, &error_abort));
306     remaining = qlist_size(keypairs) / 2;
307     assert(remaining);
308 
309     while (remaining--) {
310         name = qobject_to(QString, qlist_pop(keypairs));
311         value = qobject_to(QString, qlist_pop(keypairs));
312         assert(name && value);
313         key = qstring_get_str(name);
314 
315         ret = rados_conf_set(cluster, key, qstring_get_str(value));
316         qobject_unref(value);
317         if (ret < 0) {
318             error_setg_errno(errp, -ret, "invalid conf option %s", key);
319             qobject_unref(name);
320             ret = -EINVAL;
321             break;
322         }
323         qobject_unref(name);
324     }
325 
326     qobject_unref(keypairs);
327     return ret;
328 }
329 
330 #ifdef LIBRBD_SUPPORTS_ENCRYPTION
331 static int qemu_rbd_convert_luks_options(
332         RbdEncryptionOptionsLUKSBase *luks_opts,
333         char **passphrase,
334         size_t *passphrase_len,
335         Error **errp)
336 {
337     return qcrypto_secret_lookup(luks_opts->key_secret, (uint8_t **)passphrase,
338                                  passphrase_len, errp);
339 }
340 
341 static int qemu_rbd_convert_luks_create_options(
342         RbdEncryptionCreateOptionsLUKSBase *luks_opts,
343         rbd_encryption_algorithm_t *alg,
344         char **passphrase,
345         size_t *passphrase_len,
346         Error **errp)
347 {
348     int r = 0;
349 
350     r = qemu_rbd_convert_luks_options(
351             qapi_RbdEncryptionCreateOptionsLUKSBase_base(luks_opts),
352             passphrase, passphrase_len, errp);
353     if (r < 0) {
354         return r;
355     }
356 
357     if (luks_opts->has_cipher_alg) {
358         switch (luks_opts->cipher_alg) {
359             case QCRYPTO_CIPHER_ALG_AES_128: {
360                 *alg = RBD_ENCRYPTION_ALGORITHM_AES128;
361                 break;
362             }
363             case QCRYPTO_CIPHER_ALG_AES_256: {
364                 *alg = RBD_ENCRYPTION_ALGORITHM_AES256;
365                 break;
366             }
367             default: {
368                 r = -ENOTSUP;
369                 error_setg_errno(errp, -r, "unknown encryption algorithm: %u",
370                                  luks_opts->cipher_alg);
371                 return r;
372             }
373         }
374     } else {
375         /* default alg */
376         *alg = RBD_ENCRYPTION_ALGORITHM_AES256;
377     }
378 
379     return 0;
380 }
381 
382 static int qemu_rbd_encryption_format(rbd_image_t image,
383                                       RbdEncryptionCreateOptions *encrypt,
384                                       Error **errp)
385 {
386     int r = 0;
387     g_autofree char *passphrase = NULL;
388     size_t passphrase_len;
389     rbd_encryption_format_t format;
390     rbd_encryption_options_t opts;
391     rbd_encryption_luks1_format_options_t luks_opts;
392     rbd_encryption_luks2_format_options_t luks2_opts;
393     size_t opts_size;
394     uint64_t raw_size, effective_size;
395 
396     r = rbd_get_size(image, &raw_size);
397     if (r < 0) {
398         error_setg_errno(errp, -r, "cannot get raw image size");
399         return r;
400     }
401 
402     switch (encrypt->format) {
403         case RBD_IMAGE_ENCRYPTION_FORMAT_LUKS: {
404             memset(&luks_opts, 0, sizeof(luks_opts));
405             format = RBD_ENCRYPTION_FORMAT_LUKS1;
406             opts = &luks_opts;
407             opts_size = sizeof(luks_opts);
408             r = qemu_rbd_convert_luks_create_options(
409                     qapi_RbdEncryptionCreateOptionsLUKS_base(&encrypt->u.luks),
410                     &luks_opts.alg, &passphrase, &passphrase_len, errp);
411             if (r < 0) {
412                 return r;
413             }
414             luks_opts.passphrase = passphrase;
415             luks_opts.passphrase_size = passphrase_len;
416             break;
417         }
418         case RBD_IMAGE_ENCRYPTION_FORMAT_LUKS2: {
419             memset(&luks2_opts, 0, sizeof(luks2_opts));
420             format = RBD_ENCRYPTION_FORMAT_LUKS2;
421             opts = &luks2_opts;
422             opts_size = sizeof(luks2_opts);
423             r = qemu_rbd_convert_luks_create_options(
424                     qapi_RbdEncryptionCreateOptionsLUKS2_base(
425                             &encrypt->u.luks2),
426                     &luks2_opts.alg, &passphrase, &passphrase_len, errp);
427             if (r < 0) {
428                 return r;
429             }
430             luks2_opts.passphrase = passphrase;
431             luks2_opts.passphrase_size = passphrase_len;
432             break;
433         }
434         default: {
435             r = -ENOTSUP;
436             error_setg_errno(
437                     errp, -r, "unknown image encryption format: %u",
438                     encrypt->format);
439             return r;
440         }
441     }
442 
443     r = rbd_encryption_format(image, format, opts, opts_size);
444     if (r < 0) {
445         error_setg_errno(errp, -r, "encryption format fail");
446         return r;
447     }
448 
449     r = rbd_get_size(image, &effective_size);
450     if (r < 0) {
451         error_setg_errno(errp, -r, "cannot get effective image size");
452         return r;
453     }
454 
455     r = rbd_resize(image, raw_size + (raw_size - effective_size));
456     if (r < 0) {
457         error_setg_errno(errp, -r, "cannot resize image after format");
458         return r;
459     }
460 
461     return 0;
462 }
463 
464 static int qemu_rbd_encryption_load(rbd_image_t image,
465                                     RbdEncryptionOptions *encrypt,
466                                     Error **errp)
467 {
468     int r = 0;
469     g_autofree char *passphrase = NULL;
470     size_t passphrase_len;
471     rbd_encryption_luks1_format_options_t luks_opts;
472     rbd_encryption_luks2_format_options_t luks2_opts;
473     rbd_encryption_format_t format;
474     rbd_encryption_options_t opts;
475     size_t opts_size;
476 
477     switch (encrypt->format) {
478         case RBD_IMAGE_ENCRYPTION_FORMAT_LUKS: {
479             memset(&luks_opts, 0, sizeof(luks_opts));
480             format = RBD_ENCRYPTION_FORMAT_LUKS1;
481             opts = &luks_opts;
482             opts_size = sizeof(luks_opts);
483             r = qemu_rbd_convert_luks_options(
484                     qapi_RbdEncryptionOptionsLUKS_base(&encrypt->u.luks),
485                     &passphrase, &passphrase_len, errp);
486             if (r < 0) {
487                 return r;
488             }
489             luks_opts.passphrase = passphrase;
490             luks_opts.passphrase_size = passphrase_len;
491             break;
492         }
493         case RBD_IMAGE_ENCRYPTION_FORMAT_LUKS2: {
494             memset(&luks2_opts, 0, sizeof(luks2_opts));
495             format = RBD_ENCRYPTION_FORMAT_LUKS2;
496             opts = &luks2_opts;
497             opts_size = sizeof(luks2_opts);
498             r = qemu_rbd_convert_luks_options(
499                     qapi_RbdEncryptionOptionsLUKS2_base(&encrypt->u.luks2),
500                     &passphrase, &passphrase_len, errp);
501             if (r < 0) {
502                 return r;
503             }
504             luks2_opts.passphrase = passphrase;
505             luks2_opts.passphrase_size = passphrase_len;
506             break;
507         }
508         default: {
509             r = -ENOTSUP;
510             error_setg_errno(
511                     errp, -r, "unknown image encryption format: %u",
512                     encrypt->format);
513             return r;
514         }
515     }
516 
517     r = rbd_encryption_load(image, format, opts, opts_size);
518     if (r < 0) {
519         error_setg_errno(errp, -r, "encryption load fail");
520         return r;
521     }
522 
523     return 0;
524 }
525 #endif
526 
527 /* FIXME Deprecate and remove keypairs or make it available in QMP. */
528 static int qemu_rbd_do_create(BlockdevCreateOptions *options,
529                               const char *keypairs, const char *password_secret,
530                               Error **errp)
531 {
532     BlockdevCreateOptionsRbd *opts = &options->u.rbd;
533     rados_t cluster;
534     rados_ioctx_t io_ctx;
535     int obj_order = 0;
536     int ret;
537 
538     assert(options->driver == BLOCKDEV_DRIVER_RBD);
539     if (opts->location->has_snapshot) {
540         error_setg(errp, "Can't use snapshot name for image creation");
541         return -EINVAL;
542     }
543 
544 #ifndef LIBRBD_SUPPORTS_ENCRYPTION
545     if (opts->has_encrypt) {
546         error_setg(errp, "RBD library does not support image encryption");
547         return -ENOTSUP;
548     }
549 #endif
550 
551     if (opts->has_cluster_size) {
552         int64_t objsize = opts->cluster_size;
553         if ((objsize - 1) & objsize) {    /* not a power of 2? */
554             error_setg(errp, "obj size needs to be power of 2");
555             return -EINVAL;
556         }
557         if (objsize < 4096) {
558             error_setg(errp, "obj size too small");
559             return -EINVAL;
560         }
561         obj_order = ctz32(objsize);
562     }
563 
564     ret = qemu_rbd_connect(&cluster, &io_ctx, opts->location, false, keypairs,
565                            password_secret, errp);
566     if (ret < 0) {
567         return ret;
568     }
569 
570     ret = rbd_create(io_ctx, opts->location->image, opts->size, &obj_order);
571     if (ret < 0) {
572         error_setg_errno(errp, -ret, "error rbd create");
573         goto out;
574     }
575 
576 #ifdef LIBRBD_SUPPORTS_ENCRYPTION
577     if (opts->has_encrypt) {
578         rbd_image_t image;
579 
580         ret = rbd_open(io_ctx, opts->location->image, &image, NULL);
581         if (ret < 0) {
582             error_setg_errno(errp, -ret,
583                              "error opening image '%s' for encryption format",
584                              opts->location->image);
585             goto out;
586         }
587 
588         ret = qemu_rbd_encryption_format(image, opts->encrypt, errp);
589         rbd_close(image);
590         if (ret < 0) {
591             /* encryption format fail, try removing the image */
592             rbd_remove(io_ctx, opts->location->image);
593             goto out;
594         }
595     }
596 #endif
597 
598     ret = 0;
599 out:
600     rados_ioctx_destroy(io_ctx);
601     rados_shutdown(cluster);
602     return ret;
603 }
604 
605 static int qemu_rbd_co_create(BlockdevCreateOptions *options, Error **errp)
606 {
607     return qemu_rbd_do_create(options, NULL, NULL, errp);
608 }
609 
610 static int qemu_rbd_extract_encryption_create_options(
611         QemuOpts *opts,
612         RbdEncryptionCreateOptions **spec,
613         Error **errp)
614 {
615     QDict *opts_qdict;
616     QDict *encrypt_qdict;
617     Visitor *v;
618     int ret = 0;
619 
620     opts_qdict = qemu_opts_to_qdict(opts, NULL);
621     qdict_extract_subqdict(opts_qdict, &encrypt_qdict, "encrypt.");
622     qobject_unref(opts_qdict);
623     if (!qdict_size(encrypt_qdict)) {
624         *spec = NULL;
625         goto exit;
626     }
627 
628     /* Convert options into a QAPI object */
629     v = qobject_input_visitor_new_flat_confused(encrypt_qdict, errp);
630     if (!v) {
631         ret = -EINVAL;
632         goto exit;
633     }
634 
635     visit_type_RbdEncryptionCreateOptions(v, NULL, spec, errp);
636     visit_free(v);
637     if (!*spec) {
638         ret = -EINVAL;
639         goto exit;
640     }
641 
642 exit:
643     qobject_unref(encrypt_qdict);
644     return ret;
645 }
646 
647 static int coroutine_fn qemu_rbd_co_create_opts(BlockDriver *drv,
648                                                 const char *filename,
649                                                 QemuOpts *opts,
650                                                 Error **errp)
651 {
652     BlockdevCreateOptions *create_options;
653     BlockdevCreateOptionsRbd *rbd_opts;
654     BlockdevOptionsRbd *loc;
655     RbdEncryptionCreateOptions *encrypt = NULL;
656     Error *local_err = NULL;
657     const char *keypairs, *password_secret;
658     QDict *options = NULL;
659     int ret = 0;
660 
661     create_options = g_new0(BlockdevCreateOptions, 1);
662     create_options->driver = BLOCKDEV_DRIVER_RBD;
663     rbd_opts = &create_options->u.rbd;
664 
665     rbd_opts->location = g_new0(BlockdevOptionsRbd, 1);
666 
667     password_secret = qemu_opt_get(opts, "password-secret");
668 
669     /* Read out options */
670     rbd_opts->size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
671                               BDRV_SECTOR_SIZE);
672     rbd_opts->cluster_size = qemu_opt_get_size_del(opts,
673                                                    BLOCK_OPT_CLUSTER_SIZE, 0);
674     rbd_opts->has_cluster_size = (rbd_opts->cluster_size != 0);
675 
676     options = qdict_new();
677     qemu_rbd_parse_filename(filename, options, &local_err);
678     if (local_err) {
679         ret = -EINVAL;
680         error_propagate(errp, local_err);
681         goto exit;
682     }
683 
684     ret = qemu_rbd_extract_encryption_create_options(opts, &encrypt, errp);
685     if (ret < 0) {
686         goto exit;
687     }
688     rbd_opts->encrypt     = encrypt;
689     rbd_opts->has_encrypt = !!encrypt;
690 
691     /*
692      * Caution: while qdict_get_try_str() is fine, getting non-string
693      * types would require more care.  When @options come from -blockdev
694      * or blockdev_add, its members are typed according to the QAPI
695      * schema, but when they come from -drive, they're all QString.
696      */
697     loc = rbd_opts->location;
698     loc->pool        = g_strdup(qdict_get_try_str(options, "pool"));
699     loc->conf        = g_strdup(qdict_get_try_str(options, "conf"));
700     loc->has_conf    = !!loc->conf;
701     loc->user        = g_strdup(qdict_get_try_str(options, "user"));
702     loc->has_user    = !!loc->user;
703     loc->q_namespace = g_strdup(qdict_get_try_str(options, "namespace"));
704     loc->has_q_namespace = !!loc->q_namespace;
705     loc->image       = g_strdup(qdict_get_try_str(options, "image"));
706     keypairs         = qdict_get_try_str(options, "=keyvalue-pairs");
707 
708     ret = qemu_rbd_do_create(create_options, keypairs, password_secret, errp);
709     if (ret < 0) {
710         goto exit;
711     }
712 
713 exit:
714     qobject_unref(options);
715     qapi_free_BlockdevCreateOptions(create_options);
716     return ret;
717 }
718 
719 static char *qemu_rbd_mon_host(BlockdevOptionsRbd *opts, Error **errp)
720 {
721     const char **vals;
722     const char *host, *port;
723     char *rados_str;
724     InetSocketAddressBaseList *p;
725     int i, cnt;
726 
727     if (!opts->has_server) {
728         return NULL;
729     }
730 
731     for (cnt = 0, p = opts->server; p; p = p->next) {
732         cnt++;
733     }
734 
735     vals = g_new(const char *, cnt + 1);
736 
737     for (i = 0, p = opts->server; p; p = p->next, i++) {
738         host = p->value->host;
739         port = p->value->port;
740 
741         if (strchr(host, ':')) {
742             vals[i] = g_strdup_printf("[%s]:%s", host, port);
743         } else {
744             vals[i] = g_strdup_printf("%s:%s", host, port);
745         }
746     }
747     vals[i] = NULL;
748 
749     rados_str = i ? g_strjoinv(";", (char **)vals) : NULL;
750     g_strfreev((char **)vals);
751     return rados_str;
752 }
753 
754 static int qemu_rbd_connect(rados_t *cluster, rados_ioctx_t *io_ctx,
755                             BlockdevOptionsRbd *opts, bool cache,
756                             const char *keypairs, const char *secretid,
757                             Error **errp)
758 {
759     char *mon_host = NULL;
760     Error *local_err = NULL;
761     int r;
762 
763     if (secretid) {
764         if (opts->key_secret) {
765             error_setg(errp,
766                        "Legacy 'password-secret' clashes with 'key-secret'");
767             return -EINVAL;
768         }
769         opts->key_secret = g_strdup(secretid);
770         opts->has_key_secret = true;
771     }
772 
773     mon_host = qemu_rbd_mon_host(opts, &local_err);
774     if (local_err) {
775         error_propagate(errp, local_err);
776         r = -EINVAL;
777         goto out;
778     }
779 
780     r = rados_create(cluster, opts->user);
781     if (r < 0) {
782         error_setg_errno(errp, -r, "error initializing");
783         goto out;
784     }
785 
786     /* try default location when conf=NULL, but ignore failure */
787     r = rados_conf_read_file(*cluster, opts->conf);
788     if (opts->has_conf && r < 0) {
789         error_setg_errno(errp, -r, "error reading conf file %s", opts->conf);
790         goto failed_shutdown;
791     }
792 
793     r = qemu_rbd_set_keypairs(*cluster, keypairs, errp);
794     if (r < 0) {
795         goto failed_shutdown;
796     }
797 
798     if (mon_host) {
799         r = rados_conf_set(*cluster, "mon_host", mon_host);
800         if (r < 0) {
801             goto failed_shutdown;
802         }
803     }
804 
805     r = qemu_rbd_set_auth(*cluster, opts, errp);
806     if (r < 0) {
807         goto failed_shutdown;
808     }
809 
810     /*
811      * Fallback to more conservative semantics if setting cache
812      * options fails. Ignore errors from setting rbd_cache because the
813      * only possible error is that the option does not exist, and
814      * librbd defaults to no caching. If write through caching cannot
815      * be set up, fall back to no caching.
816      */
817     if (cache) {
818         rados_conf_set(*cluster, "rbd_cache", "true");
819     } else {
820         rados_conf_set(*cluster, "rbd_cache", "false");
821     }
822 
823     r = rados_connect(*cluster);
824     if (r < 0) {
825         error_setg_errno(errp, -r, "error connecting");
826         goto failed_shutdown;
827     }
828 
829     r = rados_ioctx_create(*cluster, opts->pool, io_ctx);
830     if (r < 0) {
831         error_setg_errno(errp, -r, "error opening pool %s", opts->pool);
832         goto failed_shutdown;
833     }
834 
835 #ifdef HAVE_RBD_NAMESPACE_EXISTS
836     if (opts->has_q_namespace && strlen(opts->q_namespace) > 0) {
837         bool exists;
838 
839         r = rbd_namespace_exists(*io_ctx, opts->q_namespace, &exists);
840         if (r < 0) {
841             error_setg_errno(errp, -r, "error checking namespace");
842             goto failed_ioctx_destroy;
843         }
844 
845         if (!exists) {
846             error_setg(errp, "namespace '%s' does not exist",
847                        opts->q_namespace);
848             r = -ENOENT;
849             goto failed_ioctx_destroy;
850         }
851     }
852 #endif
853 
854     /*
855      * Set the namespace after opening the io context on the pool,
856      * if nspace == NULL or if nspace == "", it is just as we did nothing
857      */
858     rados_ioctx_set_namespace(*io_ctx, opts->q_namespace);
859 
860     r = 0;
861     goto out;
862 
863 #ifdef HAVE_RBD_NAMESPACE_EXISTS
864 failed_ioctx_destroy:
865     rados_ioctx_destroy(*io_ctx);
866 #endif
867 failed_shutdown:
868     rados_shutdown(*cluster);
869 out:
870     g_free(mon_host);
871     return r;
872 }
873 
874 static int qemu_rbd_convert_options(QDict *options, BlockdevOptionsRbd **opts,
875                                     Error **errp)
876 {
877     Visitor *v;
878 
879     /* Convert the remaining options into a QAPI object */
880     v = qobject_input_visitor_new_flat_confused(options, errp);
881     if (!v) {
882         return -EINVAL;
883     }
884 
885     visit_type_BlockdevOptionsRbd(v, NULL, opts, errp);
886     visit_free(v);
887     if (!opts) {
888         return -EINVAL;
889     }
890 
891     return 0;
892 }
893 
894 static int qemu_rbd_attempt_legacy_options(QDict *options,
895                                            BlockdevOptionsRbd **opts,
896                                            char **keypairs)
897 {
898     char *filename;
899     int r;
900 
901     filename = g_strdup(qdict_get_try_str(options, "filename"));
902     if (!filename) {
903         return -EINVAL;
904     }
905     qdict_del(options, "filename");
906 
907     qemu_rbd_parse_filename(filename, options, NULL);
908 
909     /* keypairs freed by caller */
910     *keypairs = g_strdup(qdict_get_try_str(options, "=keyvalue-pairs"));
911     if (*keypairs) {
912         qdict_del(options, "=keyvalue-pairs");
913     }
914 
915     r = qemu_rbd_convert_options(options, opts, NULL);
916 
917     g_free(filename);
918     return r;
919 }
920 
921 static int qemu_rbd_open(BlockDriverState *bs, QDict *options, int flags,
922                          Error **errp)
923 {
924     BDRVRBDState *s = bs->opaque;
925     BlockdevOptionsRbd *opts = NULL;
926     const QDictEntry *e;
927     Error *local_err = NULL;
928     char *keypairs, *secretid;
929     rbd_image_info_t info;
930     int r;
931 
932     keypairs = g_strdup(qdict_get_try_str(options, "=keyvalue-pairs"));
933     if (keypairs) {
934         qdict_del(options, "=keyvalue-pairs");
935     }
936 
937     secretid = g_strdup(qdict_get_try_str(options, "password-secret"));
938     if (secretid) {
939         qdict_del(options, "password-secret");
940     }
941 
942     r = qemu_rbd_convert_options(options, &opts, &local_err);
943     if (local_err) {
944         /* If keypairs are present, that means some options are present in
945          * the modern option format.  Don't attempt to parse legacy option
946          * formats, as we won't support mixed usage. */
947         if (keypairs) {
948             error_propagate(errp, local_err);
949             goto out;
950         }
951 
952         /* If the initial attempt to convert and process the options failed,
953          * we may be attempting to open an image file that has the rbd options
954          * specified in the older format consisting of all key/value pairs
955          * encoded in the filename.  Go ahead and attempt to parse the
956          * filename, and see if we can pull out the required options. */
957         r = qemu_rbd_attempt_legacy_options(options, &opts, &keypairs);
958         if (r < 0) {
959             /* Propagate the original error, not the legacy parsing fallback
960              * error, as the latter was just a best-effort attempt. */
961             error_propagate(errp, local_err);
962             goto out;
963         }
964         /* Take care whenever deciding to actually deprecate; once this ability
965          * is removed, we will not be able to open any images with legacy-styled
966          * backing image strings. */
967         warn_report("RBD options encoded in the filename as keyvalue pairs "
968                     "is deprecated");
969     }
970 
971     /* Remove the processed options from the QDict (the visitor processes
972      * _all_ options in the QDict) */
973     while ((e = qdict_first(options))) {
974         qdict_del(options, e->key);
975     }
976 
977     r = qemu_rbd_connect(&s->cluster, &s->io_ctx, opts,
978                          !(flags & BDRV_O_NOCACHE), keypairs, secretid, errp);
979     if (r < 0) {
980         goto out;
981     }
982 
983     s->snap = g_strdup(opts->snapshot);
984     s->image_name = g_strdup(opts->image);
985 
986     /* rbd_open is always r/w */
987     r = rbd_open(s->io_ctx, s->image_name, &s->image, s->snap);
988     if (r < 0) {
989         error_setg_errno(errp, -r, "error reading header from %s",
990                          s->image_name);
991         goto failed_open;
992     }
993 
994     if (opts->has_encrypt) {
995 #ifdef LIBRBD_SUPPORTS_ENCRYPTION
996         r = qemu_rbd_encryption_load(s->image, opts->encrypt, errp);
997         if (r < 0) {
998             goto failed_post_open;
999         }
1000 #else
1001         r = -ENOTSUP;
1002         error_setg(errp, "RBD library does not support image encryption");
1003         goto failed_post_open;
1004 #endif
1005     }
1006 
1007     r = rbd_stat(s->image, &info, sizeof(info));
1008     if (r < 0) {
1009         error_setg_errno(errp, -r, "error getting image info from %s",
1010                          s->image_name);
1011         goto failed_post_open;
1012     }
1013     s->image_size = info.size;
1014     s->object_size = info.obj_size;
1015 
1016     /* If we are using an rbd snapshot, we must be r/o, otherwise
1017      * leave as-is */
1018     if (s->snap != NULL) {
1019         r = bdrv_apply_auto_read_only(bs, "rbd snapshots are read-only", errp);
1020         if (r < 0) {
1021             goto failed_post_open;
1022         }
1023     }
1024 
1025 #ifdef LIBRBD_SUPPORTS_WRITE_ZEROES
1026     bs->supported_zero_flags = BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK;
1027 #endif
1028 
1029     /* When extending regular files, we get zeros from the OS */
1030     bs->supported_truncate_flags = BDRV_REQ_ZERO_WRITE;
1031 
1032     r = 0;
1033     goto out;
1034 
1035 failed_post_open:
1036     rbd_close(s->image);
1037 failed_open:
1038     rados_ioctx_destroy(s->io_ctx);
1039     g_free(s->snap);
1040     g_free(s->image_name);
1041     rados_shutdown(s->cluster);
1042 out:
1043     qapi_free_BlockdevOptionsRbd(opts);
1044     g_free(keypairs);
1045     g_free(secretid);
1046     return r;
1047 }
1048 
1049 
1050 /* Since RBD is currently always opened R/W via the API,
1051  * we just need to check if we are using a snapshot or not, in
1052  * order to determine if we will allow it to be R/W */
1053 static int qemu_rbd_reopen_prepare(BDRVReopenState *state,
1054                                    BlockReopenQueue *queue, Error **errp)
1055 {
1056     BDRVRBDState *s = state->bs->opaque;
1057     int ret = 0;
1058 
1059     if (s->snap && state->flags & BDRV_O_RDWR) {
1060         error_setg(errp,
1061                    "Cannot change node '%s' to r/w when using RBD snapshot",
1062                    bdrv_get_device_or_node_name(state->bs));
1063         ret = -EINVAL;
1064     }
1065 
1066     return ret;
1067 }
1068 
1069 static void qemu_rbd_close(BlockDriverState *bs)
1070 {
1071     BDRVRBDState *s = bs->opaque;
1072 
1073     rbd_close(s->image);
1074     rados_ioctx_destroy(s->io_ctx);
1075     g_free(s->snap);
1076     g_free(s->image_name);
1077     rados_shutdown(s->cluster);
1078 }
1079 
1080 /* Resize the RBD image and update the 'image_size' with the current size */
1081 static int qemu_rbd_resize(BlockDriverState *bs, uint64_t size)
1082 {
1083     BDRVRBDState *s = bs->opaque;
1084     int r;
1085 
1086     r = rbd_resize(s->image, size);
1087     if (r < 0) {
1088         return r;
1089     }
1090 
1091     s->image_size = size;
1092 
1093     return 0;
1094 }
1095 
1096 static void qemu_rbd_finish_bh(void *opaque)
1097 {
1098     RBDTask *task = opaque;
1099     task->complete = true;
1100     aio_co_wake(task->co);
1101 }
1102 
1103 /*
1104  * This is the completion callback function for all rbd aio calls
1105  * started from qemu_rbd_start_co().
1106  *
1107  * Note: this function is being called from a non qemu thread so
1108  * we need to be careful about what we do here. Generally we only
1109  * schedule a BH, and do the rest of the io completion handling
1110  * from qemu_rbd_finish_bh() which runs in a qemu context.
1111  */
1112 static void qemu_rbd_completion_cb(rbd_completion_t c, RBDTask *task)
1113 {
1114     task->ret = rbd_aio_get_return_value(c);
1115     rbd_aio_release(c);
1116     aio_bh_schedule_oneshot(bdrv_get_aio_context(task->bs),
1117                             qemu_rbd_finish_bh, task);
1118 }
1119 
1120 static int coroutine_fn qemu_rbd_start_co(BlockDriverState *bs,
1121                                           uint64_t offset,
1122                                           uint64_t bytes,
1123                                           QEMUIOVector *qiov,
1124                                           int flags,
1125                                           RBDAIOCmd cmd)
1126 {
1127     BDRVRBDState *s = bs->opaque;
1128     RBDTask task = { .bs = bs, .co = qemu_coroutine_self() };
1129     rbd_completion_t c;
1130     int r;
1131 
1132     assert(!qiov || qiov->size == bytes);
1133 
1134     if (cmd == RBD_AIO_WRITE || cmd == RBD_AIO_WRITE_ZEROES) {
1135         /*
1136          * RBD APIs don't allow us to write more than actual size, so in order
1137          * to support growing images, we resize the image before write
1138          * operations that exceed the current size.
1139          */
1140         if (offset + bytes > s->image_size) {
1141             int r = qemu_rbd_resize(bs, offset + bytes);
1142             if (r < 0) {
1143                 return r;
1144             }
1145         }
1146     }
1147 
1148     r = rbd_aio_create_completion(&task,
1149                                   (rbd_callback_t) qemu_rbd_completion_cb, &c);
1150     if (r < 0) {
1151         return r;
1152     }
1153 
1154     switch (cmd) {
1155     case RBD_AIO_READ:
1156         r = rbd_aio_readv(s->image, qiov->iov, qiov->niov, offset, c);
1157         break;
1158     case RBD_AIO_WRITE:
1159         r = rbd_aio_writev(s->image, qiov->iov, qiov->niov, offset, c);
1160         break;
1161     case RBD_AIO_DISCARD:
1162         r = rbd_aio_discard(s->image, offset, bytes, c);
1163         break;
1164     case RBD_AIO_FLUSH:
1165         r = rbd_aio_flush(s->image, c);
1166         break;
1167 #ifdef LIBRBD_SUPPORTS_WRITE_ZEROES
1168     case RBD_AIO_WRITE_ZEROES: {
1169         int zero_flags = 0;
1170 #ifdef RBD_WRITE_ZEROES_FLAG_THICK_PROVISION
1171         if (!(flags & BDRV_REQ_MAY_UNMAP)) {
1172             zero_flags = RBD_WRITE_ZEROES_FLAG_THICK_PROVISION;
1173         }
1174 #endif
1175         r = rbd_aio_write_zeroes(s->image, offset, bytes, c, zero_flags, 0);
1176         break;
1177     }
1178 #endif
1179     default:
1180         r = -EINVAL;
1181     }
1182 
1183     if (r < 0) {
1184         error_report("rbd request failed early: cmd %d offset %" PRIu64
1185                      " bytes %" PRIu64 " flags %d r %d (%s)", cmd, offset,
1186                      bytes, flags, r, strerror(-r));
1187         rbd_aio_release(c);
1188         return r;
1189     }
1190 
1191     while (!task.complete) {
1192         qemu_coroutine_yield();
1193     }
1194 
1195     if (task.ret < 0) {
1196         error_report("rbd request failed: cmd %d offset %" PRIu64 " bytes %"
1197                      PRIu64 " flags %d task.ret %" PRIi64 " (%s)", cmd, offset,
1198                      bytes, flags, task.ret, strerror(-task.ret));
1199         return task.ret;
1200     }
1201 
1202     /* zero pad short reads */
1203     if (cmd == RBD_AIO_READ && task.ret < qiov->size) {
1204         qemu_iovec_memset(qiov, task.ret, 0, qiov->size - task.ret);
1205     }
1206 
1207     return 0;
1208 }
1209 
1210 static int
1211 coroutine_fn qemu_rbd_co_preadv(BlockDriverState *bs, int64_t offset,
1212                                 int64_t bytes, QEMUIOVector *qiov,
1213                                 BdrvRequestFlags flags)
1214 {
1215     return qemu_rbd_start_co(bs, offset, bytes, qiov, flags, RBD_AIO_READ);
1216 }
1217 
1218 static int
1219 coroutine_fn qemu_rbd_co_pwritev(BlockDriverState *bs, int64_t offset,
1220                                  int64_t bytes, QEMUIOVector *qiov,
1221                                  BdrvRequestFlags flags)
1222 {
1223     return qemu_rbd_start_co(bs, offset, bytes, qiov, flags, RBD_AIO_WRITE);
1224 }
1225 
1226 static int coroutine_fn qemu_rbd_co_flush(BlockDriverState *bs)
1227 {
1228     return qemu_rbd_start_co(bs, 0, 0, NULL, 0, RBD_AIO_FLUSH);
1229 }
1230 
1231 static int coroutine_fn qemu_rbd_co_pdiscard(BlockDriverState *bs,
1232                                              int64_t offset, int64_t bytes)
1233 {
1234     return qemu_rbd_start_co(bs, offset, bytes, NULL, 0, RBD_AIO_DISCARD);
1235 }
1236 
1237 #ifdef LIBRBD_SUPPORTS_WRITE_ZEROES
1238 static int
1239 coroutine_fn qemu_rbd_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset,
1240                                        int64_t bytes, BdrvRequestFlags flags)
1241 {
1242     return qemu_rbd_start_co(bs, offset, bytes, NULL, flags,
1243                              RBD_AIO_WRITE_ZEROES);
1244 }
1245 #endif
1246 
1247 static int qemu_rbd_getinfo(BlockDriverState *bs, BlockDriverInfo *bdi)
1248 {
1249     BDRVRBDState *s = bs->opaque;
1250     bdi->cluster_size = s->object_size;
1251     return 0;
1252 }
1253 
1254 static ImageInfoSpecific *qemu_rbd_get_specific_info(BlockDriverState *bs,
1255                                                      Error **errp)
1256 {
1257     BDRVRBDState *s = bs->opaque;
1258     ImageInfoSpecific *spec_info;
1259     char buf[RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN] = {0};
1260     int r;
1261 
1262     if (s->image_size >= RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN) {
1263         r = rbd_read(s->image, 0,
1264                      RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN, buf);
1265         if (r < 0) {
1266             error_setg_errno(errp, -r, "cannot read image start for probe");
1267             return NULL;
1268         }
1269     }
1270 
1271     spec_info = g_new(ImageInfoSpecific, 1);
1272     *spec_info = (ImageInfoSpecific){
1273         .type  = IMAGE_INFO_SPECIFIC_KIND_RBD,
1274         .u.rbd.data = g_new0(ImageInfoSpecificRbd, 1),
1275     };
1276 
1277     if (memcmp(buf, rbd_luks_header_verification,
1278                RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN) == 0) {
1279         spec_info->u.rbd.data->encryption_format =
1280                 RBD_IMAGE_ENCRYPTION_FORMAT_LUKS;
1281         spec_info->u.rbd.data->has_encryption_format = true;
1282     } else if (memcmp(buf, rbd_luks2_header_verification,
1283                RBD_ENCRYPTION_LUKS_HEADER_VERIFICATION_LEN) == 0) {
1284         spec_info->u.rbd.data->encryption_format =
1285                 RBD_IMAGE_ENCRYPTION_FORMAT_LUKS2;
1286         spec_info->u.rbd.data->has_encryption_format = true;
1287     } else {
1288         spec_info->u.rbd.data->has_encryption_format = false;
1289     }
1290 
1291     return spec_info;
1292 }
1293 
1294 /*
1295  * rbd_diff_iterate2 allows to interrupt the exection by returning a negative
1296  * value in the callback routine. Choose a value that does not conflict with
1297  * an existing exitcode and return it if we want to prematurely stop the
1298  * execution because we detected a change in the allocation status.
1299  */
1300 #define QEMU_RBD_EXIT_DIFF_ITERATE2 -9000
1301 
1302 static int qemu_rbd_diff_iterate_cb(uint64_t offs, size_t len,
1303                                     int exists, void *opaque)
1304 {
1305     RBDDiffIterateReq *req = opaque;
1306 
1307     assert(req->offs + req->bytes <= offs);
1308 
1309     /* treat a hole like an unallocated area and bail out */
1310     if (!exists) {
1311         return 0;
1312     }
1313 
1314     if (!req->exists && offs > req->offs) {
1315         /*
1316          * we started in an unallocated area and hit the first allocated
1317          * block. req->bytes must be set to the length of the unallocated area
1318          * before the allocated area. stop further processing.
1319          */
1320         req->bytes = offs - req->offs;
1321         return QEMU_RBD_EXIT_DIFF_ITERATE2;
1322     }
1323 
1324     if (req->exists && offs > req->offs + req->bytes) {
1325         /*
1326          * we started in an allocated area and jumped over an unallocated area,
1327          * req->bytes contains the length of the allocated area before the
1328          * unallocated area. stop further processing.
1329          */
1330         return QEMU_RBD_EXIT_DIFF_ITERATE2;
1331     }
1332 
1333     req->bytes += len;
1334     req->exists = true;
1335 
1336     return 0;
1337 }
1338 
1339 static int coroutine_fn qemu_rbd_co_block_status(BlockDriverState *bs,
1340                                                  bool want_zero, int64_t offset,
1341                                                  int64_t bytes, int64_t *pnum,
1342                                                  int64_t *map,
1343                                                  BlockDriverState **file)
1344 {
1345     BDRVRBDState *s = bs->opaque;
1346     int status, r;
1347     RBDDiffIterateReq req = { .offs = offset };
1348     uint64_t features, flags;
1349     uint64_t head = 0;
1350 
1351     assert(offset + bytes <= s->image_size);
1352 
1353     /* default to all sectors allocated */
1354     status = BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID;
1355     *map = offset;
1356     *file = bs;
1357     *pnum = bytes;
1358 
1359     /* check if RBD image supports fast-diff */
1360     r = rbd_get_features(s->image, &features);
1361     if (r < 0) {
1362         return status;
1363     }
1364     if (!(features & RBD_FEATURE_FAST_DIFF)) {
1365         return status;
1366     }
1367 
1368     /* check if RBD fast-diff result is valid */
1369     r = rbd_get_flags(s->image, &flags);
1370     if (r < 0) {
1371         return status;
1372     }
1373     if (flags & RBD_FLAG_FAST_DIFF_INVALID) {
1374         return status;
1375     }
1376 
1377 #if LIBRBD_VERSION_CODE < LIBRBD_VERSION(1, 17, 0)
1378     /*
1379      * librbd had a bug until early 2022 that affected all versions of ceph that
1380      * supported fast-diff. This bug results in reporting of incorrect offsets
1381      * if the offset parameter to rbd_diff_iterate2 is not object aligned.
1382      * Work around this bug by rounding down the offset to object boundaries.
1383      * This is OK because we call rbd_diff_iterate2 with whole_object = true.
1384      * However, this workaround only works for non cloned images with default
1385      * striping.
1386      *
1387      * See: https://tracker.ceph.com/issues/53784
1388      */
1389 
1390     /* check if RBD image has non-default striping enabled */
1391     if (features & RBD_FEATURE_STRIPINGV2) {
1392         return status;
1393     }
1394 
1395 #pragma GCC diagnostic push
1396 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
1397     /*
1398      * check if RBD image is a clone (= has a parent).
1399      *
1400      * rbd_get_parent_info is deprecated from Nautilus onwards, but the
1401      * replacement rbd_get_parent is not present in Luminous and Mimic.
1402      */
1403     if (rbd_get_parent_info(s->image, NULL, 0, NULL, 0, NULL, 0) != -ENOENT) {
1404         return status;
1405     }
1406 #pragma GCC diagnostic pop
1407 
1408     head = req.offs & (s->object_size - 1);
1409     req.offs -= head;
1410     bytes += head;
1411 #endif
1412 
1413     r = rbd_diff_iterate2(s->image, NULL, req.offs, bytes, true, true,
1414                           qemu_rbd_diff_iterate_cb, &req);
1415     if (r < 0 && r != QEMU_RBD_EXIT_DIFF_ITERATE2) {
1416         return status;
1417     }
1418     assert(req.bytes <= bytes);
1419     if (!req.exists) {
1420         if (r == 0) {
1421             /*
1422              * rbd_diff_iterate2 does not invoke callbacks for unallocated
1423              * areas. This here catches the case where no callback was
1424              * invoked at all (req.bytes == 0).
1425              */
1426             assert(req.bytes == 0);
1427             req.bytes = bytes;
1428         }
1429         status = BDRV_BLOCK_ZERO | BDRV_BLOCK_OFFSET_VALID;
1430     }
1431 
1432     assert(req.bytes > head);
1433     *pnum = req.bytes - head;
1434     return status;
1435 }
1436 
1437 static int64_t qemu_rbd_getlength(BlockDriverState *bs)
1438 {
1439     BDRVRBDState *s = bs->opaque;
1440     int r;
1441 
1442     r = rbd_get_size(s->image, &s->image_size);
1443     if (r < 0) {
1444         return r;
1445     }
1446 
1447     return s->image_size;
1448 }
1449 
1450 static int coroutine_fn qemu_rbd_co_truncate(BlockDriverState *bs,
1451                                              int64_t offset,
1452                                              bool exact,
1453                                              PreallocMode prealloc,
1454                                              BdrvRequestFlags flags,
1455                                              Error **errp)
1456 {
1457     int r;
1458 
1459     if (prealloc != PREALLOC_MODE_OFF) {
1460         error_setg(errp, "Unsupported preallocation mode '%s'",
1461                    PreallocMode_str(prealloc));
1462         return -ENOTSUP;
1463     }
1464 
1465     r = qemu_rbd_resize(bs, offset);
1466     if (r < 0) {
1467         error_setg_errno(errp, -r, "Failed to resize file");
1468         return r;
1469     }
1470 
1471     return 0;
1472 }
1473 
1474 static int qemu_rbd_snap_create(BlockDriverState *bs,
1475                                 QEMUSnapshotInfo *sn_info)
1476 {
1477     BDRVRBDState *s = bs->opaque;
1478     int r;
1479 
1480     if (sn_info->name[0] == '\0') {
1481         return -EINVAL; /* we need a name for rbd snapshots */
1482     }
1483 
1484     /*
1485      * rbd snapshots are using the name as the user controlled unique identifier
1486      * we can't use the rbd snapid for that purpose, as it can't be set
1487      */
1488     if (sn_info->id_str[0] != '\0' &&
1489         strcmp(sn_info->id_str, sn_info->name) != 0) {
1490         return -EINVAL;
1491     }
1492 
1493     if (strlen(sn_info->name) >= sizeof(sn_info->id_str)) {
1494         return -ERANGE;
1495     }
1496 
1497     r = rbd_snap_create(s->image, sn_info->name);
1498     if (r < 0) {
1499         error_report("failed to create snap: %s", strerror(-r));
1500         return r;
1501     }
1502 
1503     return 0;
1504 }
1505 
1506 static int qemu_rbd_snap_remove(BlockDriverState *bs,
1507                                 const char *snapshot_id,
1508                                 const char *snapshot_name,
1509                                 Error **errp)
1510 {
1511     BDRVRBDState *s = bs->opaque;
1512     int r;
1513 
1514     if (!snapshot_name) {
1515         error_setg(errp, "rbd need a valid snapshot name");
1516         return -EINVAL;
1517     }
1518 
1519     /* If snapshot_id is specified, it must be equal to name, see
1520        qemu_rbd_snap_list() */
1521     if (snapshot_id && strcmp(snapshot_id, snapshot_name)) {
1522         error_setg(errp,
1523                    "rbd do not support snapshot id, it should be NULL or "
1524                    "equal to snapshot name");
1525         return -EINVAL;
1526     }
1527 
1528     r = rbd_snap_remove(s->image, snapshot_name);
1529     if (r < 0) {
1530         error_setg_errno(errp, -r, "Failed to remove the snapshot");
1531     }
1532     return r;
1533 }
1534 
1535 static int qemu_rbd_snap_rollback(BlockDriverState *bs,
1536                                   const char *snapshot_name)
1537 {
1538     BDRVRBDState *s = bs->opaque;
1539 
1540     return rbd_snap_rollback(s->image, snapshot_name);
1541 }
1542 
1543 static int qemu_rbd_snap_list(BlockDriverState *bs,
1544                               QEMUSnapshotInfo **psn_tab)
1545 {
1546     BDRVRBDState *s = bs->opaque;
1547     QEMUSnapshotInfo *sn_info, *sn_tab = NULL;
1548     int i, snap_count;
1549     rbd_snap_info_t *snaps;
1550     int max_snaps = RBD_MAX_SNAPS;
1551 
1552     do {
1553         snaps = g_new(rbd_snap_info_t, max_snaps);
1554         snap_count = rbd_snap_list(s->image, snaps, &max_snaps);
1555         if (snap_count <= 0) {
1556             g_free(snaps);
1557         }
1558     } while (snap_count == -ERANGE);
1559 
1560     if (snap_count <= 0) {
1561         goto done;
1562     }
1563 
1564     sn_tab = g_new0(QEMUSnapshotInfo, snap_count);
1565 
1566     for (i = 0; i < snap_count; i++) {
1567         const char *snap_name = snaps[i].name;
1568 
1569         sn_info = sn_tab + i;
1570         pstrcpy(sn_info->id_str, sizeof(sn_info->id_str), snap_name);
1571         pstrcpy(sn_info->name, sizeof(sn_info->name), snap_name);
1572 
1573         sn_info->vm_state_size = snaps[i].size;
1574         sn_info->date_sec = 0;
1575         sn_info->date_nsec = 0;
1576         sn_info->vm_clock_nsec = 0;
1577     }
1578     rbd_snap_list_end(snaps);
1579     g_free(snaps);
1580 
1581  done:
1582     *psn_tab = sn_tab;
1583     return snap_count;
1584 }
1585 
1586 static void coroutine_fn qemu_rbd_co_invalidate_cache(BlockDriverState *bs,
1587                                                       Error **errp)
1588 {
1589     BDRVRBDState *s = bs->opaque;
1590     int r = rbd_invalidate_cache(s->image);
1591     if (r < 0) {
1592         error_setg_errno(errp, -r, "Failed to invalidate the cache");
1593     }
1594 }
1595 
1596 static QemuOptsList qemu_rbd_create_opts = {
1597     .name = "rbd-create-opts",
1598     .head = QTAILQ_HEAD_INITIALIZER(qemu_rbd_create_opts.head),
1599     .desc = {
1600         {
1601             .name = BLOCK_OPT_SIZE,
1602             .type = QEMU_OPT_SIZE,
1603             .help = "Virtual disk size"
1604         },
1605         {
1606             .name = BLOCK_OPT_CLUSTER_SIZE,
1607             .type = QEMU_OPT_SIZE,
1608             .help = "RBD object size"
1609         },
1610         {
1611             .name = "password-secret",
1612             .type = QEMU_OPT_STRING,
1613             .help = "ID of secret providing the password",
1614         },
1615         {
1616             .name = "encrypt.format",
1617             .type = QEMU_OPT_STRING,
1618             .help = "Encrypt the image, format choices: 'luks', 'luks2'",
1619         },
1620         {
1621             .name = "encrypt.cipher-alg",
1622             .type = QEMU_OPT_STRING,
1623             .help = "Name of encryption cipher algorithm"
1624                     " (allowed values: aes-128, aes-256)",
1625         },
1626         {
1627             .name = "encrypt.key-secret",
1628             .type = QEMU_OPT_STRING,
1629             .help = "ID of secret providing LUKS passphrase",
1630         },
1631         { /* end of list */ }
1632     }
1633 };
1634 
1635 static const char *const qemu_rbd_strong_runtime_opts[] = {
1636     "pool",
1637     "namespace",
1638     "image",
1639     "conf",
1640     "snapshot",
1641     "user",
1642     "server.",
1643     "password-secret",
1644 
1645     NULL
1646 };
1647 
1648 static BlockDriver bdrv_rbd = {
1649     .format_name            = "rbd",
1650     .instance_size          = sizeof(BDRVRBDState),
1651     .bdrv_parse_filename    = qemu_rbd_parse_filename,
1652     .bdrv_file_open         = qemu_rbd_open,
1653     .bdrv_close             = qemu_rbd_close,
1654     .bdrv_reopen_prepare    = qemu_rbd_reopen_prepare,
1655     .bdrv_co_create         = qemu_rbd_co_create,
1656     .bdrv_co_create_opts    = qemu_rbd_co_create_opts,
1657     .bdrv_has_zero_init     = bdrv_has_zero_init_1,
1658     .bdrv_get_info          = qemu_rbd_getinfo,
1659     .bdrv_get_specific_info = qemu_rbd_get_specific_info,
1660     .create_opts            = &qemu_rbd_create_opts,
1661     .bdrv_getlength         = qemu_rbd_getlength,
1662     .bdrv_co_truncate       = qemu_rbd_co_truncate,
1663     .protocol_name          = "rbd",
1664 
1665     .bdrv_co_preadv         = qemu_rbd_co_preadv,
1666     .bdrv_co_pwritev        = qemu_rbd_co_pwritev,
1667     .bdrv_co_flush_to_disk  = qemu_rbd_co_flush,
1668     .bdrv_co_pdiscard       = qemu_rbd_co_pdiscard,
1669 #ifdef LIBRBD_SUPPORTS_WRITE_ZEROES
1670     .bdrv_co_pwrite_zeroes  = qemu_rbd_co_pwrite_zeroes,
1671 #endif
1672     .bdrv_co_block_status   = qemu_rbd_co_block_status,
1673 
1674     .bdrv_snapshot_create   = qemu_rbd_snap_create,
1675     .bdrv_snapshot_delete   = qemu_rbd_snap_remove,
1676     .bdrv_snapshot_list     = qemu_rbd_snap_list,
1677     .bdrv_snapshot_goto     = qemu_rbd_snap_rollback,
1678     .bdrv_co_invalidate_cache = qemu_rbd_co_invalidate_cache,
1679 
1680     .strong_runtime_opts    = qemu_rbd_strong_runtime_opts,
1681 };
1682 
1683 static void bdrv_rbd_init(void)
1684 {
1685     bdrv_register(&bdrv_rbd);
1686 }
1687 
1688 block_init(bdrv_rbd_init);
1689