xref: /openbmc/qemu/block/gluster.c (revision 4a09d0bb)
1 /*
2  * GlusterFS backend for QEMU
3  *
4  * Copyright (C) 2012 Bharata B Rao <bharata@linux.vnet.ibm.com>
5  *
6  * This work is licensed under the terms of the GNU GPL, version 2 or later.
7  * See the COPYING file in the top-level directory.
8  *
9  */
10 #include "qemu/osdep.h"
11 #include <glusterfs/api/glfs.h>
12 #include "block/block_int.h"
13 #include "qapi/error.h"
14 #include "qapi/qmp/qerror.h"
15 #include "qemu/uri.h"
16 #include "qemu/error-report.h"
17 #include "qemu/cutils.h"
18 
19 #define GLUSTER_OPT_FILENAME        "filename"
20 #define GLUSTER_OPT_VOLUME          "volume"
21 #define GLUSTER_OPT_PATH            "path"
22 #define GLUSTER_OPT_TYPE            "type"
23 #define GLUSTER_OPT_SERVER_PATTERN  "server."
24 #define GLUSTER_OPT_HOST            "host"
25 #define GLUSTER_OPT_PORT            "port"
26 #define GLUSTER_OPT_TO              "to"
27 #define GLUSTER_OPT_IPV4            "ipv4"
28 #define GLUSTER_OPT_IPV6            "ipv6"
29 #define GLUSTER_OPT_SOCKET          "socket"
30 #define GLUSTER_OPT_DEBUG           "debug"
31 #define GLUSTER_DEFAULT_PORT        24007
32 #define GLUSTER_DEBUG_DEFAULT       4
33 #define GLUSTER_DEBUG_MAX           9
34 #define GLUSTER_OPT_LOGFILE         "logfile"
35 #define GLUSTER_LOGFILE_DEFAULT     "-" /* handled in libgfapi as /dev/stderr */
36 
37 #define GERR_INDEX_HINT "hint: check in 'server' array index '%d'\n"
38 
39 typedef struct GlusterAIOCB {
40     int64_t size;
41     int ret;
42     Coroutine *coroutine;
43     AioContext *aio_context;
44 } GlusterAIOCB;
45 
46 typedef struct BDRVGlusterState {
47     struct glfs *glfs;
48     struct glfs_fd *fd;
49     char *logfile;
50     bool supports_seek_data;
51     int debug;
52 } BDRVGlusterState;
53 
54 typedef struct BDRVGlusterReopenState {
55     struct glfs *glfs;
56     struct glfs_fd *fd;
57 } BDRVGlusterReopenState;
58 
59 
60 typedef struct GlfsPreopened {
61     char *volume;
62     glfs_t *fs;
63     int ref;
64 } GlfsPreopened;
65 
66 typedef struct ListElement {
67     QLIST_ENTRY(ListElement) list;
68     GlfsPreopened saved;
69 } ListElement;
70 
71 static QLIST_HEAD(glfs_list, ListElement) glfs_list;
72 
73 static QemuOptsList qemu_gluster_create_opts = {
74     .name = "qemu-gluster-create-opts",
75     .head = QTAILQ_HEAD_INITIALIZER(qemu_gluster_create_opts.head),
76     .desc = {
77         {
78             .name = BLOCK_OPT_SIZE,
79             .type = QEMU_OPT_SIZE,
80             .help = "Virtual disk size"
81         },
82         {
83             .name = BLOCK_OPT_PREALLOC,
84             .type = QEMU_OPT_STRING,
85             .help = "Preallocation mode (allowed values: off, full)"
86         },
87         {
88             .name = GLUSTER_OPT_DEBUG,
89             .type = QEMU_OPT_NUMBER,
90             .help = "Gluster log level, valid range is 0-9",
91         },
92         {
93             .name = GLUSTER_OPT_LOGFILE,
94             .type = QEMU_OPT_STRING,
95             .help = "Logfile path of libgfapi",
96         },
97         { /* end of list */ }
98     }
99 };
100 
101 static QemuOptsList runtime_opts = {
102     .name = "gluster",
103     .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
104     .desc = {
105         {
106             .name = GLUSTER_OPT_FILENAME,
107             .type = QEMU_OPT_STRING,
108             .help = "URL to the gluster image",
109         },
110         {
111             .name = GLUSTER_OPT_DEBUG,
112             .type = QEMU_OPT_NUMBER,
113             .help = "Gluster log level, valid range is 0-9",
114         },
115         {
116             .name = GLUSTER_OPT_LOGFILE,
117             .type = QEMU_OPT_STRING,
118             .help = "Logfile path of libgfapi",
119         },
120         { /* end of list */ }
121     },
122 };
123 
124 static QemuOptsList runtime_json_opts = {
125     .name = "gluster_json",
126     .head = QTAILQ_HEAD_INITIALIZER(runtime_json_opts.head),
127     .desc = {
128         {
129             .name = GLUSTER_OPT_VOLUME,
130             .type = QEMU_OPT_STRING,
131             .help = "name of gluster volume where VM image resides",
132         },
133         {
134             .name = GLUSTER_OPT_PATH,
135             .type = QEMU_OPT_STRING,
136             .help = "absolute path to image file in gluster volume",
137         },
138         {
139             .name = GLUSTER_OPT_DEBUG,
140             .type = QEMU_OPT_NUMBER,
141             .help = "Gluster log level, valid range is 0-9",
142         },
143         { /* end of list */ }
144     },
145 };
146 
147 static QemuOptsList runtime_type_opts = {
148     .name = "gluster_type",
149     .head = QTAILQ_HEAD_INITIALIZER(runtime_type_opts.head),
150     .desc = {
151         {
152             .name = GLUSTER_OPT_TYPE,
153             .type = QEMU_OPT_STRING,
154             .help = "tcp|unix",
155         },
156         { /* end of list */ }
157     },
158 };
159 
160 static QemuOptsList runtime_unix_opts = {
161     .name = "gluster_unix",
162     .head = QTAILQ_HEAD_INITIALIZER(runtime_unix_opts.head),
163     .desc = {
164         {
165             .name = GLUSTER_OPT_SOCKET,
166             .type = QEMU_OPT_STRING,
167             .help = "socket file path)",
168         },
169         { /* end of list */ }
170     },
171 };
172 
173 static QemuOptsList runtime_tcp_opts = {
174     .name = "gluster_tcp",
175     .head = QTAILQ_HEAD_INITIALIZER(runtime_tcp_opts.head),
176     .desc = {
177         {
178             .name = GLUSTER_OPT_TYPE,
179             .type = QEMU_OPT_STRING,
180             .help = "tcp|unix",
181         },
182         {
183             .name = GLUSTER_OPT_HOST,
184             .type = QEMU_OPT_STRING,
185             .help = "host address (hostname/ipv4/ipv6 addresses)",
186         },
187         {
188             .name = GLUSTER_OPT_PORT,
189             .type = QEMU_OPT_STRING,
190             .help = "port number on which glusterd is listening (default 24007)",
191         },
192         {
193             .name = "to",
194             .type = QEMU_OPT_NUMBER,
195             .help = "max port number, not supported by gluster",
196         },
197         {
198             .name = "ipv4",
199             .type = QEMU_OPT_BOOL,
200             .help = "ipv4 bool value, not supported by gluster",
201         },
202         {
203             .name = "ipv6",
204             .type = QEMU_OPT_BOOL,
205             .help = "ipv6 bool value, not supported by gluster",
206         },
207         { /* end of list */ }
208     },
209 };
210 
211 static void glfs_set_preopened(const char *volume, glfs_t *fs)
212 {
213     ListElement *entry = NULL;
214 
215     entry = g_new(ListElement, 1);
216 
217     entry->saved.volume = g_strdup(volume);
218 
219     entry->saved.fs = fs;
220     entry->saved.ref = 1;
221 
222     QLIST_INSERT_HEAD(&glfs_list, entry, list);
223 }
224 
225 static glfs_t *glfs_find_preopened(const char *volume)
226 {
227     ListElement *entry = NULL;
228 
229      QLIST_FOREACH(entry, &glfs_list, list) {
230         if (strcmp(entry->saved.volume, volume) == 0) {
231             entry->saved.ref++;
232             return entry->saved.fs;
233         }
234      }
235 
236     return NULL;
237 }
238 
239 static void glfs_clear_preopened(glfs_t *fs)
240 {
241     ListElement *entry = NULL;
242     ListElement *next;
243 
244     if (fs == NULL) {
245         return;
246     }
247 
248     QLIST_FOREACH_SAFE(entry, &glfs_list, list, next) {
249         if (entry->saved.fs == fs) {
250             if (--entry->saved.ref) {
251                 return;
252             }
253 
254             QLIST_REMOVE(entry, list);
255 
256             glfs_fini(entry->saved.fs);
257             g_free(entry->saved.volume);
258             g_free(entry);
259         }
260     }
261 }
262 
263 static int parse_volume_options(BlockdevOptionsGluster *gconf, char *path)
264 {
265     char *p, *q;
266 
267     if (!path) {
268         return -EINVAL;
269     }
270 
271     /* volume */
272     p = q = path + strspn(path, "/");
273     p += strcspn(p, "/");
274     if (*p == '\0') {
275         return -EINVAL;
276     }
277     gconf->volume = g_strndup(q, p - q);
278 
279     /* path */
280     p += strspn(p, "/");
281     if (*p == '\0') {
282         return -EINVAL;
283     }
284     gconf->path = g_strdup(p);
285     return 0;
286 }
287 
288 /*
289  * file=gluster[+transport]://[host[:port]]/volume/path[?socket=...]
290  *
291  * 'gluster' is the protocol.
292  *
293  * 'transport' specifies the transport type used to connect to gluster
294  * management daemon (glusterd). Valid transport types are
295  * tcp or unix. If a transport type isn't specified, then tcp type is assumed.
296  *
297  * 'host' specifies the host where the volume file specification for
298  * the given volume resides. This can be either hostname or ipv4 address.
299  * If transport type is 'unix', then 'host' field should not be specified.
300  * The 'socket' field needs to be populated with the path to unix domain
301  * socket.
302  *
303  * 'port' is the port number on which glusterd is listening. This is optional
304  * and if not specified, QEMU will send 0 which will make gluster to use the
305  * default port. If the transport type is unix, then 'port' should not be
306  * specified.
307  *
308  * 'volume' is the name of the gluster volume which contains the VM image.
309  *
310  * 'path' is the path to the actual VM image that resides on gluster volume.
311  *
312  * Examples:
313  *
314  * file=gluster://1.2.3.4/testvol/a.img
315  * file=gluster+tcp://1.2.3.4/testvol/a.img
316  * file=gluster+tcp://1.2.3.4:24007/testvol/dir/a.img
317  * file=gluster+tcp://host.domain.com:24007/testvol/dir/a.img
318  * file=gluster+unix:///testvol/dir/a.img?socket=/tmp/glusterd.socket
319  */
320 static int qemu_gluster_parse_uri(BlockdevOptionsGluster *gconf,
321                                   const char *filename)
322 {
323     GlusterServer *gsconf;
324     URI *uri;
325     QueryParams *qp = NULL;
326     bool is_unix = false;
327     int ret = 0;
328 
329     uri = uri_parse(filename);
330     if (!uri) {
331         return -EINVAL;
332     }
333 
334     gconf->server = g_new0(GlusterServerList, 1);
335     gconf->server->value = gsconf = g_new0(GlusterServer, 1);
336 
337     /* transport */
338     if (!uri->scheme || !strcmp(uri->scheme, "gluster")) {
339         gsconf->type = GLUSTER_TRANSPORT_TCP;
340     } else if (!strcmp(uri->scheme, "gluster+tcp")) {
341         gsconf->type = GLUSTER_TRANSPORT_TCP;
342     } else if (!strcmp(uri->scheme, "gluster+unix")) {
343         gsconf->type = GLUSTER_TRANSPORT_UNIX;
344         is_unix = true;
345     } else if (!strcmp(uri->scheme, "gluster+rdma")) {
346         gsconf->type = GLUSTER_TRANSPORT_TCP;
347         error_report("Warning: rdma feature is not supported, falling "
348                      "back to tcp");
349     } else {
350         ret = -EINVAL;
351         goto out;
352     }
353 
354     ret = parse_volume_options(gconf, uri->path);
355     if (ret < 0) {
356         goto out;
357     }
358 
359     qp = query_params_parse(uri->query);
360     if (qp->n > 1 || (is_unix && !qp->n) || (!is_unix && qp->n)) {
361         ret = -EINVAL;
362         goto out;
363     }
364 
365     if (is_unix) {
366         if (uri->server || uri->port) {
367             ret = -EINVAL;
368             goto out;
369         }
370         if (strcmp(qp->p[0].name, "socket")) {
371             ret = -EINVAL;
372             goto out;
373         }
374         gsconf->u.q_unix.path = g_strdup(qp->p[0].value);
375     } else {
376         gsconf->u.tcp.host = g_strdup(uri->server ? uri->server : "localhost");
377         if (uri->port) {
378             gsconf->u.tcp.port = g_strdup_printf("%d", uri->port);
379         } else {
380             gsconf->u.tcp.port = g_strdup_printf("%d", GLUSTER_DEFAULT_PORT);
381         }
382     }
383 
384 out:
385     if (qp) {
386         query_params_free(qp);
387     }
388     uri_free(uri);
389     return ret;
390 }
391 
392 static struct glfs *qemu_gluster_glfs_init(BlockdevOptionsGluster *gconf,
393                                            Error **errp)
394 {
395     struct glfs *glfs;
396     int ret;
397     int old_errno;
398     GlusterServerList *server;
399     unsigned long long port;
400 
401     glfs = glfs_find_preopened(gconf->volume);
402     if (glfs) {
403         return glfs;
404     }
405 
406     glfs = glfs_new(gconf->volume);
407     if (!glfs) {
408         goto out;
409     }
410 
411     glfs_set_preopened(gconf->volume, glfs);
412 
413     for (server = gconf->server; server; server = server->next) {
414         if (server->value->type  == GLUSTER_TRANSPORT_UNIX) {
415             ret = glfs_set_volfile_server(glfs,
416                                    GlusterTransport_lookup[server->value->type],
417                                    server->value->u.q_unix.path, 0);
418         } else {
419             if (parse_uint_full(server->value->u.tcp.port, &port, 10) < 0 ||
420                 port > 65535) {
421                 error_setg(errp, "'%s' is not a valid port number",
422                            server->value->u.tcp.port);
423                 errno = EINVAL;
424                 goto out;
425             }
426             ret = glfs_set_volfile_server(glfs,
427                                    GlusterTransport_lookup[server->value->type],
428                                    server->value->u.tcp.host,
429                                    (int)port);
430         }
431 
432         if (ret < 0) {
433             goto out;
434         }
435     }
436 
437     ret = glfs_set_logging(glfs, gconf->logfile, gconf->debug);
438     if (ret < 0) {
439         goto out;
440     }
441 
442     ret = glfs_init(glfs);
443     if (ret) {
444         error_setg(errp, "Gluster connection for volume %s, path %s failed"
445                          " to connect", gconf->volume, gconf->path);
446         for (server = gconf->server; server; server = server->next) {
447             if (server->value->type  == GLUSTER_TRANSPORT_UNIX) {
448                 error_append_hint(errp, "hint: failed on socket %s ",
449                                   server->value->u.q_unix.path);
450             } else {
451                 error_append_hint(errp, "hint: failed on host %s and port %s ",
452                                   server->value->u.tcp.host,
453                                   server->value->u.tcp.port);
454             }
455         }
456 
457         error_append_hint(errp, "Please refer to gluster logs for more info\n");
458 
459         /* glfs_init sometimes doesn't set errno although docs suggest that */
460         if (errno == 0) {
461             errno = EINVAL;
462         }
463 
464         goto out;
465     }
466     return glfs;
467 
468 out:
469     if (glfs) {
470         old_errno = errno;
471         glfs_clear_preopened(glfs);
472         errno = old_errno;
473     }
474     return NULL;
475 }
476 
477 static int qapi_enum_parse(const char *opt)
478 {
479     int i;
480 
481     if (!opt) {
482         return GLUSTER_TRANSPORT__MAX;
483     }
484 
485     for (i = 0; i < GLUSTER_TRANSPORT__MAX; i++) {
486         if (!strcmp(opt, GlusterTransport_lookup[i])) {
487             return i;
488         }
489     }
490 
491     return i;
492 }
493 
494 /*
495  * Convert the json formatted command line into qapi.
496 */
497 static int qemu_gluster_parse_json(BlockdevOptionsGluster *gconf,
498                                   QDict *options, Error **errp)
499 {
500     QemuOpts *opts;
501     GlusterServer *gsconf;
502     GlusterServerList *curr = NULL;
503     QDict *backing_options = NULL;
504     Error *local_err = NULL;
505     char *str = NULL;
506     const char *ptr;
507     size_t num_servers;
508     int i;
509 
510     /* create opts info from runtime_json_opts list */
511     opts = qemu_opts_create(&runtime_json_opts, NULL, 0, &error_abort);
512     qemu_opts_absorb_qdict(opts, options, &local_err);
513     if (local_err) {
514         goto out;
515     }
516 
517     num_servers = qdict_array_entries(options, GLUSTER_OPT_SERVER_PATTERN);
518     if (num_servers < 1) {
519         error_setg(&local_err, QERR_MISSING_PARAMETER, "server");
520         goto out;
521     }
522 
523     ptr = qemu_opt_get(opts, GLUSTER_OPT_VOLUME);
524     if (!ptr) {
525         error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_VOLUME);
526         goto out;
527     }
528     gconf->volume = g_strdup(ptr);
529 
530     ptr = qemu_opt_get(opts, GLUSTER_OPT_PATH);
531     if (!ptr) {
532         error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_PATH);
533         goto out;
534     }
535     gconf->path = g_strdup(ptr);
536     qemu_opts_del(opts);
537 
538     for (i = 0; i < num_servers; i++) {
539         str = g_strdup_printf(GLUSTER_OPT_SERVER_PATTERN"%d.", i);
540         qdict_extract_subqdict(options, &backing_options, str);
541 
542         /* create opts info from runtime_type_opts list */
543         opts = qemu_opts_create(&runtime_type_opts, NULL, 0, &error_abort);
544         qemu_opts_absorb_qdict(opts, backing_options, &local_err);
545         if (local_err) {
546             goto out;
547         }
548 
549         ptr = qemu_opt_get(opts, GLUSTER_OPT_TYPE);
550         gsconf = g_new0(GlusterServer, 1);
551         gsconf->type = qapi_enum_parse(ptr);
552         if (!ptr) {
553             error_setg(&local_err, QERR_MISSING_PARAMETER, GLUSTER_OPT_TYPE);
554             error_append_hint(&local_err, GERR_INDEX_HINT, i);
555             goto out;
556 
557         }
558         if (gsconf->type == GLUSTER_TRANSPORT__MAX) {
559             error_setg(&local_err, QERR_INVALID_PARAMETER_VALUE,
560                        GLUSTER_OPT_TYPE, "tcp or unix");
561             error_append_hint(&local_err, GERR_INDEX_HINT, i);
562             goto out;
563         }
564         qemu_opts_del(opts);
565 
566         if (gsconf->type == GLUSTER_TRANSPORT_TCP) {
567             /* create opts info from runtime_tcp_opts list */
568             opts = qemu_opts_create(&runtime_tcp_opts, NULL, 0, &error_abort);
569             qemu_opts_absorb_qdict(opts, backing_options, &local_err);
570             if (local_err) {
571                 goto out;
572             }
573 
574             ptr = qemu_opt_get(opts, GLUSTER_OPT_HOST);
575             if (!ptr) {
576                 error_setg(&local_err, QERR_MISSING_PARAMETER,
577                            GLUSTER_OPT_HOST);
578                 error_append_hint(&local_err, GERR_INDEX_HINT, i);
579                 goto out;
580             }
581             gsconf->u.tcp.host = g_strdup(ptr);
582             ptr = qemu_opt_get(opts, GLUSTER_OPT_PORT);
583             if (!ptr) {
584                 error_setg(&local_err, QERR_MISSING_PARAMETER,
585                            GLUSTER_OPT_PORT);
586                 error_append_hint(&local_err, GERR_INDEX_HINT, i);
587                 goto out;
588             }
589             gsconf->u.tcp.port = g_strdup(ptr);
590 
591             /* defend for unsupported fields in InetSocketAddress,
592              * i.e. @ipv4, @ipv6  and @to
593              */
594             ptr = qemu_opt_get(opts, GLUSTER_OPT_TO);
595             if (ptr) {
596                 gsconf->u.tcp.has_to = true;
597             }
598             ptr = qemu_opt_get(opts, GLUSTER_OPT_IPV4);
599             if (ptr) {
600                 gsconf->u.tcp.has_ipv4 = true;
601             }
602             ptr = qemu_opt_get(opts, GLUSTER_OPT_IPV6);
603             if (ptr) {
604                 gsconf->u.tcp.has_ipv6 = true;
605             }
606             if (gsconf->u.tcp.has_to) {
607                 error_setg(&local_err, "Parameter 'to' not supported");
608                 goto out;
609             }
610             if (gsconf->u.tcp.has_ipv4 || gsconf->u.tcp.has_ipv6) {
611                 error_setg(&local_err, "Parameters 'ipv4/ipv6' not supported");
612                 goto out;
613             }
614             qemu_opts_del(opts);
615         } else {
616             /* create opts info from runtime_unix_opts list */
617             opts = qemu_opts_create(&runtime_unix_opts, NULL, 0, &error_abort);
618             qemu_opts_absorb_qdict(opts, backing_options, &local_err);
619             if (local_err) {
620                 goto out;
621             }
622 
623             ptr = qemu_opt_get(opts, GLUSTER_OPT_SOCKET);
624             if (!ptr) {
625                 error_setg(&local_err, QERR_MISSING_PARAMETER,
626                            GLUSTER_OPT_SOCKET);
627                 error_append_hint(&local_err, GERR_INDEX_HINT, i);
628                 goto out;
629             }
630             gsconf->u.q_unix.path = g_strdup(ptr);
631             qemu_opts_del(opts);
632         }
633 
634         if (gconf->server == NULL) {
635             gconf->server = g_new0(GlusterServerList, 1);
636             gconf->server->value = gsconf;
637             curr = gconf->server;
638         } else {
639             curr->next = g_new0(GlusterServerList, 1);
640             curr->next->value = gsconf;
641             curr = curr->next;
642         }
643 
644         qdict_del(backing_options, str);
645         g_free(str);
646         str = NULL;
647     }
648 
649     return 0;
650 
651 out:
652     error_propagate(errp, local_err);
653     qemu_opts_del(opts);
654     if (str) {
655         qdict_del(backing_options, str);
656         g_free(str);
657     }
658     errno = EINVAL;
659     return -errno;
660 }
661 
662 static struct glfs *qemu_gluster_init(BlockdevOptionsGluster *gconf,
663                                       const char *filename,
664                                       QDict *options, Error **errp)
665 {
666     int ret;
667     if (filename) {
668         ret = qemu_gluster_parse_uri(gconf, filename);
669         if (ret < 0) {
670             error_setg(errp, "invalid URI");
671             error_append_hint(errp, "Usage: file=gluster[+transport]://"
672                                     "[host[:port]]volume/path[?socket=...]"
673                                     "[,file.debug=N]"
674                                     "[,file.logfile=/path/filename.log]\n");
675             errno = -ret;
676             return NULL;
677         }
678     } else {
679         ret = qemu_gluster_parse_json(gconf, options, errp);
680         if (ret < 0) {
681             error_append_hint(errp, "Usage: "
682                              "-drive driver=qcow2,file.driver=gluster,"
683                              "file.volume=testvol,file.path=/path/a.qcow2"
684                              "[,file.debug=9]"
685                              "[,file.logfile=/path/filename.log],"
686                              "file.server.0.type=tcp,"
687                              "file.server.0.host=1.2.3.4,"
688                              "file.server.0.port=24007,"
689                              "file.server.1.transport=unix,"
690                              "file.server.1.socket=/var/run/glusterd.socket ..."
691                              "\n");
692             errno = -ret;
693             return NULL;
694         }
695 
696     }
697 
698     return qemu_gluster_glfs_init(gconf, errp);
699 }
700 
701 static void qemu_gluster_complete_aio(void *opaque)
702 {
703     GlusterAIOCB *acb = (GlusterAIOCB *)opaque;
704 
705     qemu_coroutine_enter(acb->coroutine);
706 }
707 
708 /*
709  * AIO callback routine called from GlusterFS thread.
710  */
711 static void gluster_finish_aiocb(struct glfs_fd *fd, ssize_t ret, void *arg)
712 {
713     GlusterAIOCB *acb = (GlusterAIOCB *)arg;
714 
715     if (!ret || ret == acb->size) {
716         acb->ret = 0; /* Success */
717     } else if (ret < 0) {
718         acb->ret = -errno; /* Read/Write failed */
719     } else {
720         acb->ret = -EIO; /* Partial read/write - fail it */
721     }
722 
723     aio_bh_schedule_oneshot(acb->aio_context, qemu_gluster_complete_aio, acb);
724 }
725 
726 static void qemu_gluster_parse_flags(int bdrv_flags, int *open_flags)
727 {
728     assert(open_flags != NULL);
729 
730     *open_flags |= O_BINARY;
731 
732     if (bdrv_flags & BDRV_O_RDWR) {
733         *open_flags |= O_RDWR;
734     } else {
735         *open_flags |= O_RDONLY;
736     }
737 
738     if ((bdrv_flags & BDRV_O_NOCACHE)) {
739         *open_flags |= O_DIRECT;
740     }
741 }
742 
743 /*
744  * Do SEEK_DATA/HOLE to detect if it is functional. Older broken versions of
745  * gfapi incorrectly return the current offset when SEEK_DATA/HOLE is used.
746  * - Corrected versions return -1 and set errno to EINVAL.
747  * - Versions that support SEEK_DATA/HOLE correctly, will return -1 and set
748  *   errno to ENXIO when SEEK_DATA is called with a position of EOF.
749  */
750 static bool qemu_gluster_test_seek(struct glfs_fd *fd)
751 {
752     off_t ret = 0;
753 
754 #if defined SEEK_HOLE && defined SEEK_DATA
755     off_t eof;
756 
757     eof = glfs_lseek(fd, 0, SEEK_END);
758     if (eof < 0) {
759         /* this should never occur */
760         return false;
761     }
762 
763     /* this should always fail with ENXIO if SEEK_DATA is supported */
764     ret = glfs_lseek(fd, eof, SEEK_DATA);
765 #endif
766 
767     return (ret < 0) && (errno == ENXIO);
768 }
769 
770 static int qemu_gluster_open(BlockDriverState *bs,  QDict *options,
771                              int bdrv_flags, Error **errp)
772 {
773     BDRVGlusterState *s = bs->opaque;
774     int open_flags = 0;
775     int ret = 0;
776     BlockdevOptionsGluster *gconf = NULL;
777     QemuOpts *opts;
778     Error *local_err = NULL;
779     const char *filename, *logfile;
780 
781     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
782     qemu_opts_absorb_qdict(opts, options, &local_err);
783     if (local_err) {
784         error_propagate(errp, local_err);
785         ret = -EINVAL;
786         goto out;
787     }
788 
789     filename = qemu_opt_get(opts, GLUSTER_OPT_FILENAME);
790 
791     s->debug = qemu_opt_get_number(opts, GLUSTER_OPT_DEBUG,
792                                    GLUSTER_DEBUG_DEFAULT);
793     if (s->debug < 0) {
794         s->debug = 0;
795     } else if (s->debug > GLUSTER_DEBUG_MAX) {
796         s->debug = GLUSTER_DEBUG_MAX;
797     }
798 
799     gconf = g_new0(BlockdevOptionsGluster, 1);
800     gconf->debug = s->debug;
801     gconf->has_debug = true;
802 
803     logfile = qemu_opt_get(opts, GLUSTER_OPT_LOGFILE);
804     s->logfile = g_strdup(logfile ? logfile : GLUSTER_LOGFILE_DEFAULT);
805 
806     gconf->logfile = g_strdup(s->logfile);
807     gconf->has_logfile = true;
808 
809     s->glfs = qemu_gluster_init(gconf, filename, options, errp);
810     if (!s->glfs) {
811         ret = -errno;
812         goto out;
813     }
814 
815 #ifdef CONFIG_GLUSTERFS_XLATOR_OPT
816     /* Without this, if fsync fails for a recoverable reason (for instance,
817      * ENOSPC), gluster will dump its cache, preventing retries.  This means
818      * almost certain data loss.  Not all gluster versions support the
819      * 'resync-failed-syncs-after-fsync' key value, but there is no way to
820      * discover during runtime if it is supported (this api returns success for
821      * unknown key/value pairs) */
822     ret = glfs_set_xlator_option(s->glfs, "*-write-behind",
823                                           "resync-failed-syncs-after-fsync",
824                                           "on");
825     if (ret < 0) {
826         error_setg_errno(errp, errno, "Unable to set xlator key/value pair");
827         ret = -errno;
828         goto out;
829     }
830 #endif
831 
832     qemu_gluster_parse_flags(bdrv_flags, &open_flags);
833 
834     s->fd = glfs_open(s->glfs, gconf->path, open_flags);
835     if (!s->fd) {
836         ret = -errno;
837     }
838 
839     s->supports_seek_data = qemu_gluster_test_seek(s->fd);
840 
841 out:
842     qemu_opts_del(opts);
843     qapi_free_BlockdevOptionsGluster(gconf);
844     if (!ret) {
845         return ret;
846     }
847     g_free(s->logfile);
848     if (s->fd) {
849         glfs_close(s->fd);
850     }
851 
852     glfs_clear_preopened(s->glfs);
853 
854     return ret;
855 }
856 
857 static int qemu_gluster_reopen_prepare(BDRVReopenState *state,
858                                        BlockReopenQueue *queue, Error **errp)
859 {
860     int ret = 0;
861     BDRVGlusterState *s;
862     BDRVGlusterReopenState *reop_s;
863     BlockdevOptionsGluster *gconf;
864     int open_flags = 0;
865 
866     assert(state != NULL);
867     assert(state->bs != NULL);
868 
869     s = state->bs->opaque;
870 
871     state->opaque = g_new0(BDRVGlusterReopenState, 1);
872     reop_s = state->opaque;
873 
874     qemu_gluster_parse_flags(state->flags, &open_flags);
875 
876     gconf = g_new0(BlockdevOptionsGluster, 1);
877     gconf->debug = s->debug;
878     gconf->has_debug = true;
879     gconf->logfile = g_strdup(s->logfile);
880     gconf->has_logfile = true;
881     reop_s->glfs = qemu_gluster_init(gconf, state->bs->filename, NULL, errp);
882     if (reop_s->glfs == NULL) {
883         ret = -errno;
884         goto exit;
885     }
886 
887 #ifdef CONFIG_GLUSTERFS_XLATOR_OPT
888     ret = glfs_set_xlator_option(reop_s->glfs, "*-write-behind",
889                                  "resync-failed-syncs-after-fsync", "on");
890     if (ret < 0) {
891         error_setg_errno(errp, errno, "Unable to set xlator key/value pair");
892         ret = -errno;
893         goto exit;
894     }
895 #endif
896 
897     reop_s->fd = glfs_open(reop_s->glfs, gconf->path, open_flags);
898     if (reop_s->fd == NULL) {
899         /* reops->glfs will be cleaned up in _abort */
900         ret = -errno;
901         goto exit;
902     }
903 
904 exit:
905     /* state->opaque will be freed in either the _abort or _commit */
906     qapi_free_BlockdevOptionsGluster(gconf);
907     return ret;
908 }
909 
910 static void qemu_gluster_reopen_commit(BDRVReopenState *state)
911 {
912     BDRVGlusterReopenState *reop_s = state->opaque;
913     BDRVGlusterState *s = state->bs->opaque;
914 
915 
916     /* close the old */
917     if (s->fd) {
918         glfs_close(s->fd);
919     }
920 
921     glfs_clear_preopened(s->glfs);
922 
923     /* use the newly opened image / connection */
924     s->fd         = reop_s->fd;
925     s->glfs       = reop_s->glfs;
926 
927     g_free(state->opaque);
928     state->opaque = NULL;
929 
930     return;
931 }
932 
933 
934 static void qemu_gluster_reopen_abort(BDRVReopenState *state)
935 {
936     BDRVGlusterReopenState *reop_s = state->opaque;
937 
938     if (reop_s == NULL) {
939         return;
940     }
941 
942     if (reop_s->fd) {
943         glfs_close(reop_s->fd);
944     }
945 
946     glfs_clear_preopened(reop_s->glfs);
947 
948     g_free(state->opaque);
949     state->opaque = NULL;
950 
951     return;
952 }
953 
954 #ifdef CONFIG_GLUSTERFS_ZEROFILL
955 static coroutine_fn int qemu_gluster_co_pwrite_zeroes(BlockDriverState *bs,
956                                                       int64_t offset,
957                                                       int size,
958                                                       BdrvRequestFlags flags)
959 {
960     int ret;
961     GlusterAIOCB acb;
962     BDRVGlusterState *s = bs->opaque;
963 
964     acb.size = size;
965     acb.ret = 0;
966     acb.coroutine = qemu_coroutine_self();
967     acb.aio_context = bdrv_get_aio_context(bs);
968 
969     ret = glfs_zerofill_async(s->fd, offset, size, gluster_finish_aiocb, &acb);
970     if (ret < 0) {
971         return -errno;
972     }
973 
974     qemu_coroutine_yield();
975     return acb.ret;
976 }
977 
978 static inline bool gluster_supports_zerofill(void)
979 {
980     return 1;
981 }
982 
983 static inline int qemu_gluster_zerofill(struct glfs_fd *fd, int64_t offset,
984                                         int64_t size)
985 {
986     return glfs_zerofill(fd, offset, size);
987 }
988 
989 #else
990 static inline bool gluster_supports_zerofill(void)
991 {
992     return 0;
993 }
994 
995 static inline int qemu_gluster_zerofill(struct glfs_fd *fd, int64_t offset,
996                                         int64_t size)
997 {
998     return 0;
999 }
1000 #endif
1001 
1002 static int qemu_gluster_create(const char *filename,
1003                                QemuOpts *opts, Error **errp)
1004 {
1005     BlockdevOptionsGluster *gconf;
1006     struct glfs *glfs;
1007     struct glfs_fd *fd;
1008     int ret = 0;
1009     int prealloc = 0;
1010     int64_t total_size = 0;
1011     char *tmp = NULL;
1012 
1013     gconf = g_new0(BlockdevOptionsGluster, 1);
1014     gconf->debug = qemu_opt_get_number_del(opts, GLUSTER_OPT_DEBUG,
1015                                            GLUSTER_DEBUG_DEFAULT);
1016     if (gconf->debug < 0) {
1017         gconf->debug = 0;
1018     } else if (gconf->debug > GLUSTER_DEBUG_MAX) {
1019         gconf->debug = GLUSTER_DEBUG_MAX;
1020     }
1021     gconf->has_debug = true;
1022 
1023     gconf->logfile = qemu_opt_get_del(opts, GLUSTER_OPT_LOGFILE);
1024     if (!gconf->logfile) {
1025         gconf->logfile = g_strdup(GLUSTER_LOGFILE_DEFAULT);
1026     }
1027     gconf->has_logfile = true;
1028 
1029     glfs = qemu_gluster_init(gconf, filename, NULL, errp);
1030     if (!glfs) {
1031         ret = -errno;
1032         goto out;
1033     }
1034 
1035     total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
1036                           BDRV_SECTOR_SIZE);
1037 
1038     tmp = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC);
1039     if (!tmp || !strcmp(tmp, "off")) {
1040         prealloc = 0;
1041     } else if (!strcmp(tmp, "full") && gluster_supports_zerofill()) {
1042         prealloc = 1;
1043     } else {
1044         error_setg(errp, "Invalid preallocation mode: '%s'"
1045                          " or GlusterFS doesn't support zerofill API", tmp);
1046         ret = -EINVAL;
1047         goto out;
1048     }
1049 
1050     fd = glfs_creat(glfs, gconf->path,
1051                     O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IRUSR | S_IWUSR);
1052     if (!fd) {
1053         ret = -errno;
1054     } else {
1055         if (!glfs_ftruncate(fd, total_size)) {
1056             if (prealloc && qemu_gluster_zerofill(fd, 0, total_size)) {
1057                 ret = -errno;
1058             }
1059         } else {
1060             ret = -errno;
1061         }
1062 
1063         if (glfs_close(fd) != 0) {
1064             ret = -errno;
1065         }
1066     }
1067 out:
1068     g_free(tmp);
1069     qapi_free_BlockdevOptionsGluster(gconf);
1070     glfs_clear_preopened(glfs);
1071     return ret;
1072 }
1073 
1074 static coroutine_fn int qemu_gluster_co_rw(BlockDriverState *bs,
1075                                            int64_t sector_num, int nb_sectors,
1076                                            QEMUIOVector *qiov, int write)
1077 {
1078     int ret;
1079     GlusterAIOCB acb;
1080     BDRVGlusterState *s = bs->opaque;
1081     size_t size = nb_sectors * BDRV_SECTOR_SIZE;
1082     off_t offset = sector_num * BDRV_SECTOR_SIZE;
1083 
1084     acb.size = size;
1085     acb.ret = 0;
1086     acb.coroutine = qemu_coroutine_self();
1087     acb.aio_context = bdrv_get_aio_context(bs);
1088 
1089     if (write) {
1090         ret = glfs_pwritev_async(s->fd, qiov->iov, qiov->niov, offset, 0,
1091                                  gluster_finish_aiocb, &acb);
1092     } else {
1093         ret = glfs_preadv_async(s->fd, qiov->iov, qiov->niov, offset, 0,
1094                                 gluster_finish_aiocb, &acb);
1095     }
1096 
1097     if (ret < 0) {
1098         return -errno;
1099     }
1100 
1101     qemu_coroutine_yield();
1102     return acb.ret;
1103 }
1104 
1105 static int qemu_gluster_truncate(BlockDriverState *bs, int64_t offset)
1106 {
1107     int ret;
1108     BDRVGlusterState *s = bs->opaque;
1109 
1110     ret = glfs_ftruncate(s->fd, offset);
1111     if (ret < 0) {
1112         return -errno;
1113     }
1114 
1115     return 0;
1116 }
1117 
1118 static coroutine_fn int qemu_gluster_co_readv(BlockDriverState *bs,
1119                                               int64_t sector_num,
1120                                               int nb_sectors,
1121                                               QEMUIOVector *qiov)
1122 {
1123     return qemu_gluster_co_rw(bs, sector_num, nb_sectors, qiov, 0);
1124 }
1125 
1126 static coroutine_fn int qemu_gluster_co_writev(BlockDriverState *bs,
1127                                                int64_t sector_num,
1128                                                int nb_sectors,
1129                                                QEMUIOVector *qiov)
1130 {
1131     return qemu_gluster_co_rw(bs, sector_num, nb_sectors, qiov, 1);
1132 }
1133 
1134 static void qemu_gluster_close(BlockDriverState *bs)
1135 {
1136     BDRVGlusterState *s = bs->opaque;
1137 
1138     g_free(s->logfile);
1139     if (s->fd) {
1140         glfs_close(s->fd);
1141         s->fd = NULL;
1142     }
1143     glfs_clear_preopened(s->glfs);
1144 }
1145 
1146 static coroutine_fn int qemu_gluster_co_flush_to_disk(BlockDriverState *bs)
1147 {
1148     int ret;
1149     GlusterAIOCB acb;
1150     BDRVGlusterState *s = bs->opaque;
1151 
1152     acb.size = 0;
1153     acb.ret = 0;
1154     acb.coroutine = qemu_coroutine_self();
1155     acb.aio_context = bdrv_get_aio_context(bs);
1156 
1157     ret = glfs_fsync_async(s->fd, gluster_finish_aiocb, &acb);
1158     if (ret < 0) {
1159         ret = -errno;
1160         goto error;
1161     }
1162 
1163     qemu_coroutine_yield();
1164     if (acb.ret < 0) {
1165         ret = acb.ret;
1166         goto error;
1167     }
1168 
1169     return acb.ret;
1170 
1171 error:
1172     /* Some versions of Gluster (3.5.6 -> 3.5.8?) will not retain its cache
1173      * after a fsync failure, so we have no way of allowing the guest to safely
1174      * continue.  Gluster versions prior to 3.5.6 don't retain the cache
1175      * either, but will invalidate the fd on error, so this is again our only
1176      * option.
1177      *
1178      * The 'resync-failed-syncs-after-fsync' xlator option for the
1179      * write-behind cache will cause later gluster versions to retain its
1180      * cache after error, so long as the fd remains open.  However, we
1181      * currently have no way of knowing if this option is supported.
1182      *
1183      * TODO: Once gluster provides a way for us to determine if the option
1184      * is supported, bypass the closure and setting drv to NULL.  */
1185     qemu_gluster_close(bs);
1186     bs->drv = NULL;
1187     return ret;
1188 }
1189 
1190 #ifdef CONFIG_GLUSTERFS_DISCARD
1191 static coroutine_fn int qemu_gluster_co_pdiscard(BlockDriverState *bs,
1192                                                  int64_t offset, int size)
1193 {
1194     int ret;
1195     GlusterAIOCB acb;
1196     BDRVGlusterState *s = bs->opaque;
1197 
1198     acb.size = 0;
1199     acb.ret = 0;
1200     acb.coroutine = qemu_coroutine_self();
1201     acb.aio_context = bdrv_get_aio_context(bs);
1202 
1203     ret = glfs_discard_async(s->fd, offset, size, gluster_finish_aiocb, &acb);
1204     if (ret < 0) {
1205         return -errno;
1206     }
1207 
1208     qemu_coroutine_yield();
1209     return acb.ret;
1210 }
1211 #endif
1212 
1213 static int64_t qemu_gluster_getlength(BlockDriverState *bs)
1214 {
1215     BDRVGlusterState *s = bs->opaque;
1216     int64_t ret;
1217 
1218     ret = glfs_lseek(s->fd, 0, SEEK_END);
1219     if (ret < 0) {
1220         return -errno;
1221     } else {
1222         return ret;
1223     }
1224 }
1225 
1226 static int64_t qemu_gluster_allocated_file_size(BlockDriverState *bs)
1227 {
1228     BDRVGlusterState *s = bs->opaque;
1229     struct stat st;
1230     int ret;
1231 
1232     ret = glfs_fstat(s->fd, &st);
1233     if (ret < 0) {
1234         return -errno;
1235     } else {
1236         return st.st_blocks * 512;
1237     }
1238 }
1239 
1240 static int qemu_gluster_has_zero_init(BlockDriverState *bs)
1241 {
1242     /* GlusterFS volume could be backed by a block device */
1243     return 0;
1244 }
1245 
1246 /*
1247  * Find allocation range in @bs around offset @start.
1248  * May change underlying file descriptor's file offset.
1249  * If @start is not in a hole, store @start in @data, and the
1250  * beginning of the next hole in @hole, and return 0.
1251  * If @start is in a non-trailing hole, store @start in @hole and the
1252  * beginning of the next non-hole in @data, and return 0.
1253  * If @start is in a trailing hole or beyond EOF, return -ENXIO.
1254  * If we can't find out, return a negative errno other than -ENXIO.
1255  *
1256  * (Shamefully copied from file-posix.c, only miniscule adaptions.)
1257  */
1258 static int find_allocation(BlockDriverState *bs, off_t start,
1259                            off_t *data, off_t *hole)
1260 {
1261     BDRVGlusterState *s = bs->opaque;
1262 
1263     if (!s->supports_seek_data) {
1264         goto exit;
1265     }
1266 
1267 #if defined SEEK_HOLE && defined SEEK_DATA
1268     off_t offs;
1269 
1270     /*
1271      * SEEK_DATA cases:
1272      * D1. offs == start: start is in data
1273      * D2. offs > start: start is in a hole, next data at offs
1274      * D3. offs < 0, errno = ENXIO: either start is in a trailing hole
1275      *                              or start is beyond EOF
1276      *     If the latter happens, the file has been truncated behind
1277      *     our back since we opened it.  All bets are off then.
1278      *     Treating like a trailing hole is simplest.
1279      * D4. offs < 0, errno != ENXIO: we learned nothing
1280      */
1281     offs = glfs_lseek(s->fd, start, SEEK_DATA);
1282     if (offs < 0) {
1283         return -errno;          /* D3 or D4 */
1284     }
1285     assert(offs >= start);
1286 
1287     if (offs > start) {
1288         /* D2: in hole, next data at offs */
1289         *hole = start;
1290         *data = offs;
1291         return 0;
1292     }
1293 
1294     /* D1: in data, end not yet known */
1295 
1296     /*
1297      * SEEK_HOLE cases:
1298      * H1. offs == start: start is in a hole
1299      *     If this happens here, a hole has been dug behind our back
1300      *     since the previous lseek().
1301      * H2. offs > start: either start is in data, next hole at offs,
1302      *                   or start is in trailing hole, EOF at offs
1303      *     Linux treats trailing holes like any other hole: offs ==
1304      *     start.  Solaris seeks to EOF instead: offs > start (blech).
1305      *     If that happens here, a hole has been dug behind our back
1306      *     since the previous lseek().
1307      * H3. offs < 0, errno = ENXIO: start is beyond EOF
1308      *     If this happens, the file has been truncated behind our
1309      *     back since we opened it.  Treat it like a trailing hole.
1310      * H4. offs < 0, errno != ENXIO: we learned nothing
1311      *     Pretend we know nothing at all, i.e. "forget" about D1.
1312      */
1313     offs = glfs_lseek(s->fd, start, SEEK_HOLE);
1314     if (offs < 0) {
1315         return -errno;          /* D1 and (H3 or H4) */
1316     }
1317     assert(offs >= start);
1318 
1319     if (offs > start) {
1320         /*
1321          * D1 and H2: either in data, next hole at offs, or it was in
1322          * data but is now in a trailing hole.  In the latter case,
1323          * all bets are off.  Treating it as if it there was data all
1324          * the way to EOF is safe, so simply do that.
1325          */
1326         *data = start;
1327         *hole = offs;
1328         return 0;
1329     }
1330 
1331     /* D1 and H1 */
1332     return -EBUSY;
1333 #endif
1334 
1335 exit:
1336     return -ENOTSUP;
1337 }
1338 
1339 /*
1340  * Returns the allocation status of the specified sectors.
1341  *
1342  * If 'sector_num' is beyond the end of the disk image the return value is 0
1343  * and 'pnum' is set to 0.
1344  *
1345  * 'pnum' is set to the number of sectors (including and immediately following
1346  * the specified sector) that are known to be in the same
1347  * allocated/unallocated state.
1348  *
1349  * 'nb_sectors' is the max value 'pnum' should be set to.  If nb_sectors goes
1350  * beyond the end of the disk image it will be clamped.
1351  *
1352  * (Based on raw_co_get_block_status() from file-posix.c.)
1353  */
1354 static int64_t coroutine_fn qemu_gluster_co_get_block_status(
1355         BlockDriverState *bs, int64_t sector_num, int nb_sectors, int *pnum,
1356         BlockDriverState **file)
1357 {
1358     BDRVGlusterState *s = bs->opaque;
1359     off_t start, data = 0, hole = 0;
1360     int64_t total_size;
1361     int ret = -EINVAL;
1362 
1363     if (!s->fd) {
1364         return ret;
1365     }
1366 
1367     start = sector_num * BDRV_SECTOR_SIZE;
1368     total_size = bdrv_getlength(bs);
1369     if (total_size < 0) {
1370         return total_size;
1371     } else if (start >= total_size) {
1372         *pnum = 0;
1373         return 0;
1374     } else if (start + nb_sectors * BDRV_SECTOR_SIZE > total_size) {
1375         nb_sectors = DIV_ROUND_UP(total_size - start, BDRV_SECTOR_SIZE);
1376     }
1377 
1378     ret = find_allocation(bs, start, &data, &hole);
1379     if (ret == -ENXIO) {
1380         /* Trailing hole */
1381         *pnum = nb_sectors;
1382         ret = BDRV_BLOCK_ZERO;
1383     } else if (ret < 0) {
1384         /* No info available, so pretend there are no holes */
1385         *pnum = nb_sectors;
1386         ret = BDRV_BLOCK_DATA;
1387     } else if (data == start) {
1388         /* On a data extent, compute sectors to the end of the extent,
1389          * possibly including a partial sector at EOF. */
1390         *pnum = MIN(nb_sectors, DIV_ROUND_UP(hole - start, BDRV_SECTOR_SIZE));
1391         ret = BDRV_BLOCK_DATA;
1392     } else {
1393         /* On a hole, compute sectors to the beginning of the next extent.  */
1394         assert(hole == start);
1395         *pnum = MIN(nb_sectors, (data - start) / BDRV_SECTOR_SIZE);
1396         ret = BDRV_BLOCK_ZERO;
1397     }
1398 
1399     *file = bs;
1400 
1401     return ret | BDRV_BLOCK_OFFSET_VALID | start;
1402 }
1403 
1404 
1405 static BlockDriver bdrv_gluster = {
1406     .format_name                  = "gluster",
1407     .protocol_name                = "gluster",
1408     .instance_size                = sizeof(BDRVGlusterState),
1409     .bdrv_needs_filename          = false,
1410     .bdrv_file_open               = qemu_gluster_open,
1411     .bdrv_reopen_prepare          = qemu_gluster_reopen_prepare,
1412     .bdrv_reopen_commit           = qemu_gluster_reopen_commit,
1413     .bdrv_reopen_abort            = qemu_gluster_reopen_abort,
1414     .bdrv_close                   = qemu_gluster_close,
1415     .bdrv_create                  = qemu_gluster_create,
1416     .bdrv_getlength               = qemu_gluster_getlength,
1417     .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size,
1418     .bdrv_truncate                = qemu_gluster_truncate,
1419     .bdrv_co_readv                = qemu_gluster_co_readv,
1420     .bdrv_co_writev               = qemu_gluster_co_writev,
1421     .bdrv_co_flush_to_disk        = qemu_gluster_co_flush_to_disk,
1422     .bdrv_has_zero_init           = qemu_gluster_has_zero_init,
1423 #ifdef CONFIG_GLUSTERFS_DISCARD
1424     .bdrv_co_pdiscard             = qemu_gluster_co_pdiscard,
1425 #endif
1426 #ifdef CONFIG_GLUSTERFS_ZEROFILL
1427     .bdrv_co_pwrite_zeroes        = qemu_gluster_co_pwrite_zeroes,
1428 #endif
1429     .bdrv_co_get_block_status     = qemu_gluster_co_get_block_status,
1430     .create_opts                  = &qemu_gluster_create_opts,
1431 };
1432 
1433 static BlockDriver bdrv_gluster_tcp = {
1434     .format_name                  = "gluster",
1435     .protocol_name                = "gluster+tcp",
1436     .instance_size                = sizeof(BDRVGlusterState),
1437     .bdrv_needs_filename          = false,
1438     .bdrv_file_open               = qemu_gluster_open,
1439     .bdrv_reopen_prepare          = qemu_gluster_reopen_prepare,
1440     .bdrv_reopen_commit           = qemu_gluster_reopen_commit,
1441     .bdrv_reopen_abort            = qemu_gluster_reopen_abort,
1442     .bdrv_close                   = qemu_gluster_close,
1443     .bdrv_create                  = qemu_gluster_create,
1444     .bdrv_getlength               = qemu_gluster_getlength,
1445     .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size,
1446     .bdrv_truncate                = qemu_gluster_truncate,
1447     .bdrv_co_readv                = qemu_gluster_co_readv,
1448     .bdrv_co_writev               = qemu_gluster_co_writev,
1449     .bdrv_co_flush_to_disk        = qemu_gluster_co_flush_to_disk,
1450     .bdrv_has_zero_init           = qemu_gluster_has_zero_init,
1451 #ifdef CONFIG_GLUSTERFS_DISCARD
1452     .bdrv_co_pdiscard             = qemu_gluster_co_pdiscard,
1453 #endif
1454 #ifdef CONFIG_GLUSTERFS_ZEROFILL
1455     .bdrv_co_pwrite_zeroes        = qemu_gluster_co_pwrite_zeroes,
1456 #endif
1457     .bdrv_co_get_block_status     = qemu_gluster_co_get_block_status,
1458     .create_opts                  = &qemu_gluster_create_opts,
1459 };
1460 
1461 static BlockDriver bdrv_gluster_unix = {
1462     .format_name                  = "gluster",
1463     .protocol_name                = "gluster+unix",
1464     .instance_size                = sizeof(BDRVGlusterState),
1465     .bdrv_needs_filename          = true,
1466     .bdrv_file_open               = qemu_gluster_open,
1467     .bdrv_reopen_prepare          = qemu_gluster_reopen_prepare,
1468     .bdrv_reopen_commit           = qemu_gluster_reopen_commit,
1469     .bdrv_reopen_abort            = qemu_gluster_reopen_abort,
1470     .bdrv_close                   = qemu_gluster_close,
1471     .bdrv_create                  = qemu_gluster_create,
1472     .bdrv_getlength               = qemu_gluster_getlength,
1473     .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size,
1474     .bdrv_truncate                = qemu_gluster_truncate,
1475     .bdrv_co_readv                = qemu_gluster_co_readv,
1476     .bdrv_co_writev               = qemu_gluster_co_writev,
1477     .bdrv_co_flush_to_disk        = qemu_gluster_co_flush_to_disk,
1478     .bdrv_has_zero_init           = qemu_gluster_has_zero_init,
1479 #ifdef CONFIG_GLUSTERFS_DISCARD
1480     .bdrv_co_pdiscard             = qemu_gluster_co_pdiscard,
1481 #endif
1482 #ifdef CONFIG_GLUSTERFS_ZEROFILL
1483     .bdrv_co_pwrite_zeroes        = qemu_gluster_co_pwrite_zeroes,
1484 #endif
1485     .bdrv_co_get_block_status     = qemu_gluster_co_get_block_status,
1486     .create_opts                  = &qemu_gluster_create_opts,
1487 };
1488 
1489 /* rdma is deprecated (actually never supported for volfile fetch).
1490  * Let's maintain it for the protocol compatibility, to make sure things
1491  * won't break immediately. For now, gluster+rdma will fall back to gluster+tcp
1492  * protocol with a warning.
1493  * TODO: remove gluster+rdma interface support
1494  */
1495 static BlockDriver bdrv_gluster_rdma = {
1496     .format_name                  = "gluster",
1497     .protocol_name                = "gluster+rdma",
1498     .instance_size                = sizeof(BDRVGlusterState),
1499     .bdrv_needs_filename          = true,
1500     .bdrv_file_open               = qemu_gluster_open,
1501     .bdrv_reopen_prepare          = qemu_gluster_reopen_prepare,
1502     .bdrv_reopen_commit           = qemu_gluster_reopen_commit,
1503     .bdrv_reopen_abort            = qemu_gluster_reopen_abort,
1504     .bdrv_close                   = qemu_gluster_close,
1505     .bdrv_create                  = qemu_gluster_create,
1506     .bdrv_getlength               = qemu_gluster_getlength,
1507     .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size,
1508     .bdrv_truncate                = qemu_gluster_truncate,
1509     .bdrv_co_readv                = qemu_gluster_co_readv,
1510     .bdrv_co_writev               = qemu_gluster_co_writev,
1511     .bdrv_co_flush_to_disk        = qemu_gluster_co_flush_to_disk,
1512     .bdrv_has_zero_init           = qemu_gluster_has_zero_init,
1513 #ifdef CONFIG_GLUSTERFS_DISCARD
1514     .bdrv_co_pdiscard             = qemu_gluster_co_pdiscard,
1515 #endif
1516 #ifdef CONFIG_GLUSTERFS_ZEROFILL
1517     .bdrv_co_pwrite_zeroes        = qemu_gluster_co_pwrite_zeroes,
1518 #endif
1519     .bdrv_co_get_block_status     = qemu_gluster_co_get_block_status,
1520     .create_opts                  = &qemu_gluster_create_opts,
1521 };
1522 
1523 static void bdrv_gluster_init(void)
1524 {
1525     bdrv_register(&bdrv_gluster_rdma);
1526     bdrv_register(&bdrv_gluster_unix);
1527     bdrv_register(&bdrv_gluster_tcp);
1528     bdrv_register(&bdrv_gluster);
1529 }
1530 
1531 block_init(bdrv_gluster_init);
1532