xref: /qemu/block/gluster.c (revision b30d1886)
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 /*
702  * AIO callback routine called from GlusterFS thread.
703  */
704 static void gluster_finish_aiocb(struct glfs_fd *fd, ssize_t ret, void *arg)
705 {
706     GlusterAIOCB *acb = (GlusterAIOCB *)arg;
707 
708     if (!ret || ret == acb->size) {
709         acb->ret = 0; /* Success */
710     } else if (ret < 0) {
711         acb->ret = -errno; /* Read/Write failed */
712     } else {
713         acb->ret = -EIO; /* Partial read/write - fail it */
714     }
715 
716     aio_co_schedule(acb->aio_context, acb->coroutine);
717 }
718 
719 static void qemu_gluster_parse_flags(int bdrv_flags, int *open_flags)
720 {
721     assert(open_flags != NULL);
722 
723     *open_flags |= O_BINARY;
724 
725     if (bdrv_flags & BDRV_O_RDWR) {
726         *open_flags |= O_RDWR;
727     } else {
728         *open_flags |= O_RDONLY;
729     }
730 
731     if ((bdrv_flags & BDRV_O_NOCACHE)) {
732         *open_flags |= O_DIRECT;
733     }
734 }
735 
736 /*
737  * Do SEEK_DATA/HOLE to detect if it is functional. Older broken versions of
738  * gfapi incorrectly return the current offset when SEEK_DATA/HOLE is used.
739  * - Corrected versions return -1 and set errno to EINVAL.
740  * - Versions that support SEEK_DATA/HOLE correctly, will return -1 and set
741  *   errno to ENXIO when SEEK_DATA is called with a position of EOF.
742  */
743 static bool qemu_gluster_test_seek(struct glfs_fd *fd)
744 {
745     off_t ret = 0;
746 
747 #if defined SEEK_HOLE && defined SEEK_DATA
748     off_t eof;
749 
750     eof = glfs_lseek(fd, 0, SEEK_END);
751     if (eof < 0) {
752         /* this should never occur */
753         return false;
754     }
755 
756     /* this should always fail with ENXIO if SEEK_DATA is supported */
757     ret = glfs_lseek(fd, eof, SEEK_DATA);
758 #endif
759 
760     return (ret < 0) && (errno == ENXIO);
761 }
762 
763 static int qemu_gluster_open(BlockDriverState *bs,  QDict *options,
764                              int bdrv_flags, Error **errp)
765 {
766     BDRVGlusterState *s = bs->opaque;
767     int open_flags = 0;
768     int ret = 0;
769     BlockdevOptionsGluster *gconf = NULL;
770     QemuOpts *opts;
771     Error *local_err = NULL;
772     const char *filename, *logfile;
773 
774     opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
775     qemu_opts_absorb_qdict(opts, options, &local_err);
776     if (local_err) {
777         error_propagate(errp, local_err);
778         ret = -EINVAL;
779         goto out;
780     }
781 
782     filename = qemu_opt_get(opts, GLUSTER_OPT_FILENAME);
783 
784     s->debug = qemu_opt_get_number(opts, GLUSTER_OPT_DEBUG,
785                                    GLUSTER_DEBUG_DEFAULT);
786     if (s->debug < 0) {
787         s->debug = 0;
788     } else if (s->debug > GLUSTER_DEBUG_MAX) {
789         s->debug = GLUSTER_DEBUG_MAX;
790     }
791 
792     gconf = g_new0(BlockdevOptionsGluster, 1);
793     gconf->debug = s->debug;
794     gconf->has_debug = true;
795 
796     logfile = qemu_opt_get(opts, GLUSTER_OPT_LOGFILE);
797     s->logfile = g_strdup(logfile ? logfile : GLUSTER_LOGFILE_DEFAULT);
798 
799     gconf->logfile = g_strdup(s->logfile);
800     gconf->has_logfile = true;
801 
802     s->glfs = qemu_gluster_init(gconf, filename, options, errp);
803     if (!s->glfs) {
804         ret = -errno;
805         goto out;
806     }
807 
808 #ifdef CONFIG_GLUSTERFS_XLATOR_OPT
809     /* Without this, if fsync fails for a recoverable reason (for instance,
810      * ENOSPC), gluster will dump its cache, preventing retries.  This means
811      * almost certain data loss.  Not all gluster versions support the
812      * 'resync-failed-syncs-after-fsync' key value, but there is no way to
813      * discover during runtime if it is supported (this api returns success for
814      * unknown key/value pairs) */
815     ret = glfs_set_xlator_option(s->glfs, "*-write-behind",
816                                           "resync-failed-syncs-after-fsync",
817                                           "on");
818     if (ret < 0) {
819         error_setg_errno(errp, errno, "Unable to set xlator key/value pair");
820         ret = -errno;
821         goto out;
822     }
823 #endif
824 
825     qemu_gluster_parse_flags(bdrv_flags, &open_flags);
826 
827     s->fd = glfs_open(s->glfs, gconf->path, open_flags);
828     if (!s->fd) {
829         ret = -errno;
830     }
831 
832     s->supports_seek_data = qemu_gluster_test_seek(s->fd);
833 
834 out:
835     qemu_opts_del(opts);
836     qapi_free_BlockdevOptionsGluster(gconf);
837     if (!ret) {
838         return ret;
839     }
840     g_free(s->logfile);
841     if (s->fd) {
842         glfs_close(s->fd);
843     }
844 
845     glfs_clear_preopened(s->glfs);
846 
847     return ret;
848 }
849 
850 static int qemu_gluster_reopen_prepare(BDRVReopenState *state,
851                                        BlockReopenQueue *queue, Error **errp)
852 {
853     int ret = 0;
854     BDRVGlusterState *s;
855     BDRVGlusterReopenState *reop_s;
856     BlockdevOptionsGluster *gconf;
857     int open_flags = 0;
858 
859     assert(state != NULL);
860     assert(state->bs != NULL);
861 
862     s = state->bs->opaque;
863 
864     state->opaque = g_new0(BDRVGlusterReopenState, 1);
865     reop_s = state->opaque;
866 
867     qemu_gluster_parse_flags(state->flags, &open_flags);
868 
869     gconf = g_new0(BlockdevOptionsGluster, 1);
870     gconf->debug = s->debug;
871     gconf->has_debug = true;
872     gconf->logfile = g_strdup(s->logfile);
873     gconf->has_logfile = true;
874     reop_s->glfs = qemu_gluster_init(gconf, state->bs->filename, NULL, errp);
875     if (reop_s->glfs == NULL) {
876         ret = -errno;
877         goto exit;
878     }
879 
880 #ifdef CONFIG_GLUSTERFS_XLATOR_OPT
881     ret = glfs_set_xlator_option(reop_s->glfs, "*-write-behind",
882                                  "resync-failed-syncs-after-fsync", "on");
883     if (ret < 0) {
884         error_setg_errno(errp, errno, "Unable to set xlator key/value pair");
885         ret = -errno;
886         goto exit;
887     }
888 #endif
889 
890     reop_s->fd = glfs_open(reop_s->glfs, gconf->path, open_flags);
891     if (reop_s->fd == NULL) {
892         /* reops->glfs will be cleaned up in _abort */
893         ret = -errno;
894         goto exit;
895     }
896 
897 exit:
898     /* state->opaque will be freed in either the _abort or _commit */
899     qapi_free_BlockdevOptionsGluster(gconf);
900     return ret;
901 }
902 
903 static void qemu_gluster_reopen_commit(BDRVReopenState *state)
904 {
905     BDRVGlusterReopenState *reop_s = state->opaque;
906     BDRVGlusterState *s = state->bs->opaque;
907 
908 
909     /* close the old */
910     if (s->fd) {
911         glfs_close(s->fd);
912     }
913 
914     glfs_clear_preopened(s->glfs);
915 
916     /* use the newly opened image / connection */
917     s->fd         = reop_s->fd;
918     s->glfs       = reop_s->glfs;
919 
920     g_free(state->opaque);
921     state->opaque = NULL;
922 
923     return;
924 }
925 
926 
927 static void qemu_gluster_reopen_abort(BDRVReopenState *state)
928 {
929     BDRVGlusterReopenState *reop_s = state->opaque;
930 
931     if (reop_s == NULL) {
932         return;
933     }
934 
935     if (reop_s->fd) {
936         glfs_close(reop_s->fd);
937     }
938 
939     glfs_clear_preopened(reop_s->glfs);
940 
941     g_free(state->opaque);
942     state->opaque = NULL;
943 
944     return;
945 }
946 
947 #ifdef CONFIG_GLUSTERFS_ZEROFILL
948 static coroutine_fn int qemu_gluster_co_pwrite_zeroes(BlockDriverState *bs,
949                                                       int64_t offset,
950                                                       int size,
951                                                       BdrvRequestFlags flags)
952 {
953     int ret;
954     GlusterAIOCB acb;
955     BDRVGlusterState *s = bs->opaque;
956 
957     acb.size = size;
958     acb.ret = 0;
959     acb.coroutine = qemu_coroutine_self();
960     acb.aio_context = bdrv_get_aio_context(bs);
961 
962     ret = glfs_zerofill_async(s->fd, offset, size, gluster_finish_aiocb, &acb);
963     if (ret < 0) {
964         return -errno;
965     }
966 
967     qemu_coroutine_yield();
968     return acb.ret;
969 }
970 
971 static inline bool gluster_supports_zerofill(void)
972 {
973     return 1;
974 }
975 
976 static inline int qemu_gluster_zerofill(struct glfs_fd *fd, int64_t offset,
977                                         int64_t size)
978 {
979     return glfs_zerofill(fd, offset, size);
980 }
981 
982 #else
983 static inline bool gluster_supports_zerofill(void)
984 {
985     return 0;
986 }
987 
988 static inline int qemu_gluster_zerofill(struct glfs_fd *fd, int64_t offset,
989                                         int64_t size)
990 {
991     return 0;
992 }
993 #endif
994 
995 static int qemu_gluster_create(const char *filename,
996                                QemuOpts *opts, Error **errp)
997 {
998     BlockdevOptionsGluster *gconf;
999     struct glfs *glfs;
1000     struct glfs_fd *fd;
1001     int ret = 0;
1002     int prealloc = 0;
1003     int64_t total_size = 0;
1004     char *tmp = NULL;
1005 
1006     gconf = g_new0(BlockdevOptionsGluster, 1);
1007     gconf->debug = qemu_opt_get_number_del(opts, GLUSTER_OPT_DEBUG,
1008                                            GLUSTER_DEBUG_DEFAULT);
1009     if (gconf->debug < 0) {
1010         gconf->debug = 0;
1011     } else if (gconf->debug > GLUSTER_DEBUG_MAX) {
1012         gconf->debug = GLUSTER_DEBUG_MAX;
1013     }
1014     gconf->has_debug = true;
1015 
1016     gconf->logfile = qemu_opt_get_del(opts, GLUSTER_OPT_LOGFILE);
1017     if (!gconf->logfile) {
1018         gconf->logfile = g_strdup(GLUSTER_LOGFILE_DEFAULT);
1019     }
1020     gconf->has_logfile = true;
1021 
1022     glfs = qemu_gluster_init(gconf, filename, NULL, errp);
1023     if (!glfs) {
1024         ret = -errno;
1025         goto out;
1026     }
1027 
1028     total_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0),
1029                           BDRV_SECTOR_SIZE);
1030 
1031     tmp = qemu_opt_get_del(opts, BLOCK_OPT_PREALLOC);
1032     if (!tmp || !strcmp(tmp, "off")) {
1033         prealloc = 0;
1034     } else if (!strcmp(tmp, "full") && gluster_supports_zerofill()) {
1035         prealloc = 1;
1036     } else {
1037         error_setg(errp, "Invalid preallocation mode: '%s'"
1038                          " or GlusterFS doesn't support zerofill API", tmp);
1039         ret = -EINVAL;
1040         goto out;
1041     }
1042 
1043     fd = glfs_creat(glfs, gconf->path,
1044                     O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IRUSR | S_IWUSR);
1045     if (!fd) {
1046         ret = -errno;
1047     } else {
1048         if (!glfs_ftruncate(fd, total_size)) {
1049             if (prealloc && qemu_gluster_zerofill(fd, 0, total_size)) {
1050                 ret = -errno;
1051             }
1052         } else {
1053             ret = -errno;
1054         }
1055 
1056         if (glfs_close(fd) != 0) {
1057             ret = -errno;
1058         }
1059     }
1060 out:
1061     g_free(tmp);
1062     qapi_free_BlockdevOptionsGluster(gconf);
1063     glfs_clear_preopened(glfs);
1064     return ret;
1065 }
1066 
1067 static coroutine_fn int qemu_gluster_co_rw(BlockDriverState *bs,
1068                                            int64_t sector_num, int nb_sectors,
1069                                            QEMUIOVector *qiov, int write)
1070 {
1071     int ret;
1072     GlusterAIOCB acb;
1073     BDRVGlusterState *s = bs->opaque;
1074     size_t size = nb_sectors * BDRV_SECTOR_SIZE;
1075     off_t offset = sector_num * BDRV_SECTOR_SIZE;
1076 
1077     acb.size = size;
1078     acb.ret = 0;
1079     acb.coroutine = qemu_coroutine_self();
1080     acb.aio_context = bdrv_get_aio_context(bs);
1081 
1082     if (write) {
1083         ret = glfs_pwritev_async(s->fd, qiov->iov, qiov->niov, offset, 0,
1084                                  gluster_finish_aiocb, &acb);
1085     } else {
1086         ret = glfs_preadv_async(s->fd, qiov->iov, qiov->niov, offset, 0,
1087                                 gluster_finish_aiocb, &acb);
1088     }
1089 
1090     if (ret < 0) {
1091         return -errno;
1092     }
1093 
1094     qemu_coroutine_yield();
1095     return acb.ret;
1096 }
1097 
1098 static int qemu_gluster_truncate(BlockDriverState *bs, int64_t offset)
1099 {
1100     int ret;
1101     BDRVGlusterState *s = bs->opaque;
1102 
1103     ret = glfs_ftruncate(s->fd, offset);
1104     if (ret < 0) {
1105         return -errno;
1106     }
1107 
1108     return 0;
1109 }
1110 
1111 static coroutine_fn int qemu_gluster_co_readv(BlockDriverState *bs,
1112                                               int64_t sector_num,
1113                                               int nb_sectors,
1114                                               QEMUIOVector *qiov)
1115 {
1116     return qemu_gluster_co_rw(bs, sector_num, nb_sectors, qiov, 0);
1117 }
1118 
1119 static coroutine_fn int qemu_gluster_co_writev(BlockDriverState *bs,
1120                                                int64_t sector_num,
1121                                                int nb_sectors,
1122                                                QEMUIOVector *qiov)
1123 {
1124     return qemu_gluster_co_rw(bs, sector_num, nb_sectors, qiov, 1);
1125 }
1126 
1127 static void qemu_gluster_close(BlockDriverState *bs)
1128 {
1129     BDRVGlusterState *s = bs->opaque;
1130 
1131     g_free(s->logfile);
1132     if (s->fd) {
1133         glfs_close(s->fd);
1134         s->fd = NULL;
1135     }
1136     glfs_clear_preopened(s->glfs);
1137 }
1138 
1139 static coroutine_fn int qemu_gluster_co_flush_to_disk(BlockDriverState *bs)
1140 {
1141     int ret;
1142     GlusterAIOCB acb;
1143     BDRVGlusterState *s = bs->opaque;
1144 
1145     acb.size = 0;
1146     acb.ret = 0;
1147     acb.coroutine = qemu_coroutine_self();
1148     acb.aio_context = bdrv_get_aio_context(bs);
1149 
1150     ret = glfs_fsync_async(s->fd, gluster_finish_aiocb, &acb);
1151     if (ret < 0) {
1152         ret = -errno;
1153         goto error;
1154     }
1155 
1156     qemu_coroutine_yield();
1157     if (acb.ret < 0) {
1158         ret = acb.ret;
1159         goto error;
1160     }
1161 
1162     return acb.ret;
1163 
1164 error:
1165     /* Some versions of Gluster (3.5.6 -> 3.5.8?) will not retain its cache
1166      * after a fsync failure, so we have no way of allowing the guest to safely
1167      * continue.  Gluster versions prior to 3.5.6 don't retain the cache
1168      * either, but will invalidate the fd on error, so this is again our only
1169      * option.
1170      *
1171      * The 'resync-failed-syncs-after-fsync' xlator option for the
1172      * write-behind cache will cause later gluster versions to retain its
1173      * cache after error, so long as the fd remains open.  However, we
1174      * currently have no way of knowing if this option is supported.
1175      *
1176      * TODO: Once gluster provides a way for us to determine if the option
1177      * is supported, bypass the closure and setting drv to NULL.  */
1178     qemu_gluster_close(bs);
1179     bs->drv = NULL;
1180     return ret;
1181 }
1182 
1183 #ifdef CONFIG_GLUSTERFS_DISCARD
1184 static coroutine_fn int qemu_gluster_co_pdiscard(BlockDriverState *bs,
1185                                                  int64_t offset, int size)
1186 {
1187     int ret;
1188     GlusterAIOCB acb;
1189     BDRVGlusterState *s = bs->opaque;
1190 
1191     acb.size = 0;
1192     acb.ret = 0;
1193     acb.coroutine = qemu_coroutine_self();
1194     acb.aio_context = bdrv_get_aio_context(bs);
1195 
1196     ret = glfs_discard_async(s->fd, offset, size, gluster_finish_aiocb, &acb);
1197     if (ret < 0) {
1198         return -errno;
1199     }
1200 
1201     qemu_coroutine_yield();
1202     return acb.ret;
1203 }
1204 #endif
1205 
1206 static int64_t qemu_gluster_getlength(BlockDriverState *bs)
1207 {
1208     BDRVGlusterState *s = bs->opaque;
1209     int64_t ret;
1210 
1211     ret = glfs_lseek(s->fd, 0, SEEK_END);
1212     if (ret < 0) {
1213         return -errno;
1214     } else {
1215         return ret;
1216     }
1217 }
1218 
1219 static int64_t qemu_gluster_allocated_file_size(BlockDriverState *bs)
1220 {
1221     BDRVGlusterState *s = bs->opaque;
1222     struct stat st;
1223     int ret;
1224 
1225     ret = glfs_fstat(s->fd, &st);
1226     if (ret < 0) {
1227         return -errno;
1228     } else {
1229         return st.st_blocks * 512;
1230     }
1231 }
1232 
1233 static int qemu_gluster_has_zero_init(BlockDriverState *bs)
1234 {
1235     /* GlusterFS volume could be backed by a block device */
1236     return 0;
1237 }
1238 
1239 /*
1240  * Find allocation range in @bs around offset @start.
1241  * May change underlying file descriptor's file offset.
1242  * If @start is not in a hole, store @start in @data, and the
1243  * beginning of the next hole in @hole, and return 0.
1244  * If @start is in a non-trailing hole, store @start in @hole and the
1245  * beginning of the next non-hole in @data, and return 0.
1246  * If @start is in a trailing hole or beyond EOF, return -ENXIO.
1247  * If we can't find out, return a negative errno other than -ENXIO.
1248  *
1249  * (Shamefully copied from file-posix.c, only miniscule adaptions.)
1250  */
1251 static int find_allocation(BlockDriverState *bs, off_t start,
1252                            off_t *data, off_t *hole)
1253 {
1254     BDRVGlusterState *s = bs->opaque;
1255 
1256     if (!s->supports_seek_data) {
1257         goto exit;
1258     }
1259 
1260 #if defined SEEK_HOLE && defined SEEK_DATA
1261     off_t offs;
1262 
1263     /*
1264      * SEEK_DATA cases:
1265      * D1. offs == start: start is in data
1266      * D2. offs > start: start is in a hole, next data at offs
1267      * D3. offs < 0, errno = ENXIO: either start is in a trailing hole
1268      *                              or start is beyond EOF
1269      *     If the latter happens, the file has been truncated behind
1270      *     our back since we opened it.  All bets are off then.
1271      *     Treating like a trailing hole is simplest.
1272      * D4. offs < 0, errno != ENXIO: we learned nothing
1273      */
1274     offs = glfs_lseek(s->fd, start, SEEK_DATA);
1275     if (offs < 0) {
1276         return -errno;          /* D3 or D4 */
1277     }
1278     assert(offs >= start);
1279 
1280     if (offs > start) {
1281         /* D2: in hole, next data at offs */
1282         *hole = start;
1283         *data = offs;
1284         return 0;
1285     }
1286 
1287     /* D1: in data, end not yet known */
1288 
1289     /*
1290      * SEEK_HOLE cases:
1291      * H1. offs == start: start is in a hole
1292      *     If this happens here, a hole has been dug behind our back
1293      *     since the previous lseek().
1294      * H2. offs > start: either start is in data, next hole at offs,
1295      *                   or start is in trailing hole, EOF at offs
1296      *     Linux treats trailing holes like any other hole: offs ==
1297      *     start.  Solaris seeks to EOF instead: offs > start (blech).
1298      *     If that happens here, a hole has been dug behind our back
1299      *     since the previous lseek().
1300      * H3. offs < 0, errno = ENXIO: start is beyond EOF
1301      *     If this happens, the file has been truncated behind our
1302      *     back since we opened it.  Treat it like a trailing hole.
1303      * H4. offs < 0, errno != ENXIO: we learned nothing
1304      *     Pretend we know nothing at all, i.e. "forget" about D1.
1305      */
1306     offs = glfs_lseek(s->fd, start, SEEK_HOLE);
1307     if (offs < 0) {
1308         return -errno;          /* D1 and (H3 or H4) */
1309     }
1310     assert(offs >= start);
1311 
1312     if (offs > start) {
1313         /*
1314          * D1 and H2: either in data, next hole at offs, or it was in
1315          * data but is now in a trailing hole.  In the latter case,
1316          * all bets are off.  Treating it as if it there was data all
1317          * the way to EOF is safe, so simply do that.
1318          */
1319         *data = start;
1320         *hole = offs;
1321         return 0;
1322     }
1323 
1324     /* D1 and H1 */
1325     return -EBUSY;
1326 #endif
1327 
1328 exit:
1329     return -ENOTSUP;
1330 }
1331 
1332 /*
1333  * Returns the allocation status of the specified sectors.
1334  *
1335  * If 'sector_num' is beyond the end of the disk image the return value is 0
1336  * and 'pnum' is set to 0.
1337  *
1338  * 'pnum' is set to the number of sectors (including and immediately following
1339  * the specified sector) that are known to be in the same
1340  * allocated/unallocated state.
1341  *
1342  * 'nb_sectors' is the max value 'pnum' should be set to.  If nb_sectors goes
1343  * beyond the end of the disk image it will be clamped.
1344  *
1345  * (Based on raw_co_get_block_status() from file-posix.c.)
1346  */
1347 static int64_t coroutine_fn qemu_gluster_co_get_block_status(
1348         BlockDriverState *bs, int64_t sector_num, int nb_sectors, int *pnum,
1349         BlockDriverState **file)
1350 {
1351     BDRVGlusterState *s = bs->opaque;
1352     off_t start, data = 0, hole = 0;
1353     int64_t total_size;
1354     int ret = -EINVAL;
1355 
1356     if (!s->fd) {
1357         return ret;
1358     }
1359 
1360     start = sector_num * BDRV_SECTOR_SIZE;
1361     total_size = bdrv_getlength(bs);
1362     if (total_size < 0) {
1363         return total_size;
1364     } else if (start >= total_size) {
1365         *pnum = 0;
1366         return 0;
1367     } else if (start + nb_sectors * BDRV_SECTOR_SIZE > total_size) {
1368         nb_sectors = DIV_ROUND_UP(total_size - start, BDRV_SECTOR_SIZE);
1369     }
1370 
1371     ret = find_allocation(bs, start, &data, &hole);
1372     if (ret == -ENXIO) {
1373         /* Trailing hole */
1374         *pnum = nb_sectors;
1375         ret = BDRV_BLOCK_ZERO;
1376     } else if (ret < 0) {
1377         /* No info available, so pretend there are no holes */
1378         *pnum = nb_sectors;
1379         ret = BDRV_BLOCK_DATA;
1380     } else if (data == start) {
1381         /* On a data extent, compute sectors to the end of the extent,
1382          * possibly including a partial sector at EOF. */
1383         *pnum = MIN(nb_sectors, DIV_ROUND_UP(hole - start, BDRV_SECTOR_SIZE));
1384         ret = BDRV_BLOCK_DATA;
1385     } else {
1386         /* On a hole, compute sectors to the beginning of the next extent.  */
1387         assert(hole == start);
1388         *pnum = MIN(nb_sectors, (data - start) / BDRV_SECTOR_SIZE);
1389         ret = BDRV_BLOCK_ZERO;
1390     }
1391 
1392     *file = bs;
1393 
1394     return ret | BDRV_BLOCK_OFFSET_VALID | start;
1395 }
1396 
1397 
1398 static BlockDriver bdrv_gluster = {
1399     .format_name                  = "gluster",
1400     .protocol_name                = "gluster",
1401     .instance_size                = sizeof(BDRVGlusterState),
1402     .bdrv_needs_filename          = false,
1403     .bdrv_file_open               = qemu_gluster_open,
1404     .bdrv_reopen_prepare          = qemu_gluster_reopen_prepare,
1405     .bdrv_reopen_commit           = qemu_gluster_reopen_commit,
1406     .bdrv_reopen_abort            = qemu_gluster_reopen_abort,
1407     .bdrv_close                   = qemu_gluster_close,
1408     .bdrv_create                  = qemu_gluster_create,
1409     .bdrv_getlength               = qemu_gluster_getlength,
1410     .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size,
1411     .bdrv_truncate                = qemu_gluster_truncate,
1412     .bdrv_co_readv                = qemu_gluster_co_readv,
1413     .bdrv_co_writev               = qemu_gluster_co_writev,
1414     .bdrv_co_flush_to_disk        = qemu_gluster_co_flush_to_disk,
1415     .bdrv_has_zero_init           = qemu_gluster_has_zero_init,
1416 #ifdef CONFIG_GLUSTERFS_DISCARD
1417     .bdrv_co_pdiscard             = qemu_gluster_co_pdiscard,
1418 #endif
1419 #ifdef CONFIG_GLUSTERFS_ZEROFILL
1420     .bdrv_co_pwrite_zeroes        = qemu_gluster_co_pwrite_zeroes,
1421 #endif
1422     .bdrv_co_get_block_status     = qemu_gluster_co_get_block_status,
1423     .create_opts                  = &qemu_gluster_create_opts,
1424 };
1425 
1426 static BlockDriver bdrv_gluster_tcp = {
1427     .format_name                  = "gluster",
1428     .protocol_name                = "gluster+tcp",
1429     .instance_size                = sizeof(BDRVGlusterState),
1430     .bdrv_needs_filename          = false,
1431     .bdrv_file_open               = qemu_gluster_open,
1432     .bdrv_reopen_prepare          = qemu_gluster_reopen_prepare,
1433     .bdrv_reopen_commit           = qemu_gluster_reopen_commit,
1434     .bdrv_reopen_abort            = qemu_gluster_reopen_abort,
1435     .bdrv_close                   = qemu_gluster_close,
1436     .bdrv_create                  = qemu_gluster_create,
1437     .bdrv_getlength               = qemu_gluster_getlength,
1438     .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size,
1439     .bdrv_truncate                = qemu_gluster_truncate,
1440     .bdrv_co_readv                = qemu_gluster_co_readv,
1441     .bdrv_co_writev               = qemu_gluster_co_writev,
1442     .bdrv_co_flush_to_disk        = qemu_gluster_co_flush_to_disk,
1443     .bdrv_has_zero_init           = qemu_gluster_has_zero_init,
1444 #ifdef CONFIG_GLUSTERFS_DISCARD
1445     .bdrv_co_pdiscard             = qemu_gluster_co_pdiscard,
1446 #endif
1447 #ifdef CONFIG_GLUSTERFS_ZEROFILL
1448     .bdrv_co_pwrite_zeroes        = qemu_gluster_co_pwrite_zeroes,
1449 #endif
1450     .bdrv_co_get_block_status     = qemu_gluster_co_get_block_status,
1451     .create_opts                  = &qemu_gluster_create_opts,
1452 };
1453 
1454 static BlockDriver bdrv_gluster_unix = {
1455     .format_name                  = "gluster",
1456     .protocol_name                = "gluster+unix",
1457     .instance_size                = sizeof(BDRVGlusterState),
1458     .bdrv_needs_filename          = true,
1459     .bdrv_file_open               = qemu_gluster_open,
1460     .bdrv_reopen_prepare          = qemu_gluster_reopen_prepare,
1461     .bdrv_reopen_commit           = qemu_gluster_reopen_commit,
1462     .bdrv_reopen_abort            = qemu_gluster_reopen_abort,
1463     .bdrv_close                   = qemu_gluster_close,
1464     .bdrv_create                  = qemu_gluster_create,
1465     .bdrv_getlength               = qemu_gluster_getlength,
1466     .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size,
1467     .bdrv_truncate                = qemu_gluster_truncate,
1468     .bdrv_co_readv                = qemu_gluster_co_readv,
1469     .bdrv_co_writev               = qemu_gluster_co_writev,
1470     .bdrv_co_flush_to_disk        = qemu_gluster_co_flush_to_disk,
1471     .bdrv_has_zero_init           = qemu_gluster_has_zero_init,
1472 #ifdef CONFIG_GLUSTERFS_DISCARD
1473     .bdrv_co_pdiscard             = qemu_gluster_co_pdiscard,
1474 #endif
1475 #ifdef CONFIG_GLUSTERFS_ZEROFILL
1476     .bdrv_co_pwrite_zeroes        = qemu_gluster_co_pwrite_zeroes,
1477 #endif
1478     .bdrv_co_get_block_status     = qemu_gluster_co_get_block_status,
1479     .create_opts                  = &qemu_gluster_create_opts,
1480 };
1481 
1482 /* rdma is deprecated (actually never supported for volfile fetch).
1483  * Let's maintain it for the protocol compatibility, to make sure things
1484  * won't break immediately. For now, gluster+rdma will fall back to gluster+tcp
1485  * protocol with a warning.
1486  * TODO: remove gluster+rdma interface support
1487  */
1488 static BlockDriver bdrv_gluster_rdma = {
1489     .format_name                  = "gluster",
1490     .protocol_name                = "gluster+rdma",
1491     .instance_size                = sizeof(BDRVGlusterState),
1492     .bdrv_needs_filename          = true,
1493     .bdrv_file_open               = qemu_gluster_open,
1494     .bdrv_reopen_prepare          = qemu_gluster_reopen_prepare,
1495     .bdrv_reopen_commit           = qemu_gluster_reopen_commit,
1496     .bdrv_reopen_abort            = qemu_gluster_reopen_abort,
1497     .bdrv_close                   = qemu_gluster_close,
1498     .bdrv_create                  = qemu_gluster_create,
1499     .bdrv_getlength               = qemu_gluster_getlength,
1500     .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size,
1501     .bdrv_truncate                = qemu_gluster_truncate,
1502     .bdrv_co_readv                = qemu_gluster_co_readv,
1503     .bdrv_co_writev               = qemu_gluster_co_writev,
1504     .bdrv_co_flush_to_disk        = qemu_gluster_co_flush_to_disk,
1505     .bdrv_has_zero_init           = qemu_gluster_has_zero_init,
1506 #ifdef CONFIG_GLUSTERFS_DISCARD
1507     .bdrv_co_pdiscard             = qemu_gluster_co_pdiscard,
1508 #endif
1509 #ifdef CONFIG_GLUSTERFS_ZEROFILL
1510     .bdrv_co_pwrite_zeroes        = qemu_gluster_co_pwrite_zeroes,
1511 #endif
1512     .bdrv_co_get_block_status     = qemu_gluster_co_get_block_status,
1513     .create_opts                  = &qemu_gluster_create_opts,
1514 };
1515 
1516 static void bdrv_gluster_init(void)
1517 {
1518     bdrv_register(&bdrv_gluster_rdma);
1519     bdrv_register(&bdrv_gluster_unix);
1520     bdrv_register(&bdrv_gluster_tcp);
1521     bdrv_register(&bdrv_gluster);
1522 }
1523 
1524 block_init(bdrv_gluster_init);
1525