diff options
| -rw-r--r-- | block/nbd.c | 115 | ||||
| -rw-r--r-- | blockdev-nbd.c | 20 | ||||
| -rw-r--r-- | hmp-commands.hx | 45 | ||||
| -rw-r--r-- | hmp.c | 76 | ||||
| -rw-r--r-- | hmp.h | 3 | ||||
| -rw-r--r-- | nbd.c | 25 | ||||
| -rw-r--r-- | qemu-doc.texi | 25 | ||||
| -rw-r--r-- | qemu-nbd.c | 2 |
8 files changed, 275 insertions, 36 deletions
diff --git a/block/nbd.c b/block/nbd.c index 2bce47bf7a..e87c248175 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -28,6 +28,7 @@ #include "qemu-common.h" #include "nbd.h" +#include "uri.h" #include "block_int.h" #include "module.h" #include "qemu_socket.h" @@ -55,7 +56,6 @@ typedef struct BDRVNBDState { uint32_t nbdflags; off_t size; size_t blocksize; - char *export_name; /* An NBD server may export several devices */ CoMutex send_mutex; CoMutex free_sema; @@ -65,13 +65,75 @@ typedef struct BDRVNBDState { Coroutine *recv_coroutine[MAX_NBD_REQUESTS]; struct nbd_reply reply; - /* If it begins with '/', this is a UNIX domain socket. Otherwise, - * it's a string of the form <hostname|ip4|\[ip6\]>:port - */ + int is_unix; char *host_spec; + char *export_name; /* An NBD server may export several devices */ } BDRVNBDState; -static int nbd_config(BDRVNBDState *s, const char *filename, int flags) +static int nbd_parse_uri(BDRVNBDState *s, const char *filename) +{ + URI *uri; + const char *p; + QueryParams *qp = NULL; + int ret = 0; + + uri = uri_parse(filename); + if (!uri) { + return -EINVAL; + } + + /* transport */ + if (!strcmp(uri->scheme, "nbd")) { + s->is_unix = false; + } else if (!strcmp(uri->scheme, "nbd+tcp")) { + s->is_unix = false; + } else if (!strcmp(uri->scheme, "nbd+unix")) { + s->is_unix = true; + } else { + ret = -EINVAL; + goto out; + } + + p = uri->path ? uri->path : "/"; + p += strspn(p, "/"); + if (p[0]) { + s->export_name = g_strdup(p); + } + + qp = query_params_parse(uri->query); + if (qp->n > 1 || (s->is_unix && !qp->n) || (!s->is_unix && qp->n)) { + ret = -EINVAL; + goto out; + } + + if (s->is_unix) { + /* nbd+unix:///export?socket=path */ + if (uri->server || uri->port || strcmp(qp->p[0].name, "socket")) { + ret = -EINVAL; + goto out; + } + s->host_spec = g_strdup(qp->p[0].value); + } else { + /* nbd[+tcp]://host:port/export */ + if (!uri->server) { + ret = -EINVAL; + goto out; + } + if (!uri->port) { + uri->port = NBD_DEFAULT_PORT; + } + s->host_spec = g_strdup_printf("%s:%d", uri->server, uri->port); + } + +out: + if (qp) { + query_params_free(qp); + } + uri_free(uri); + return ret; +} + +static int nbd_config(BDRVNBDState *s, const char *filename) { char *file; char *export_name; @@ -79,6 +141,10 @@ static int nbd_config(BDRVNBDState *s, const char *filename, int flags) const char *unixpath; int err = -EINVAL; + if (strstr(filename, "://")) { + return nbd_parse_uri(s, filename); + } + file = g_strdup(filename); export_name = strstr(file, EN_OPTSTR); @@ -98,11 +164,10 @@ static int nbd_config(BDRVNBDState *s, const char *filename, int flags) /* are we a UNIX or TCP socket? */ if (strstart(host_spec, "unix:", &unixpath)) { - if (unixpath[0] != '/') { /* We demand an absolute path*/ - goto out; - } + s->is_unix = true; s->host_spec = g_strdup(unixpath); } else { + s->is_unix = false; s->host_spec = g_strdup(host_spec); } @@ -262,7 +327,7 @@ static int nbd_establish_connection(BlockDriverState *bs) off_t size; size_t blocksize; - if (s->host_spec[0] == '/') { + if (s->is_unix) { sock = unix_socket_outgoing(s->host_spec); } else { sock = tcp_socket_outgoing_spec(s->host_spec); @@ -320,7 +385,7 @@ static int nbd_open(BlockDriverState *bs, const char* filename, int flags) qemu_co_mutex_init(&s->free_sema); /* Pop the config into our state object. Exit if invalid. */ - result = nbd_config(s, filename, flags); + result = nbd_config(s, filename); if (result != 0) { return result; } @@ -498,6 +563,33 @@ static int64_t nbd_getlength(BlockDriverState *bs) static BlockDriver bdrv_nbd = { .format_name = "nbd", + .protocol_name = "nbd", + .instance_size = sizeof(BDRVNBDState), + .bdrv_file_open = nbd_open, + .bdrv_co_readv = nbd_co_readv, + .bdrv_co_writev = nbd_co_writev, + .bdrv_close = nbd_close, + .bdrv_co_flush_to_os = nbd_co_flush, + .bdrv_co_discard = nbd_co_discard, + .bdrv_getlength = nbd_getlength, +}; + +static BlockDriver bdrv_nbd_tcp = { + .format_name = "nbd", + .protocol_name = "nbd+tcp", + .instance_size = sizeof(BDRVNBDState), + .bdrv_file_open = nbd_open, + .bdrv_co_readv = nbd_co_readv, + .bdrv_co_writev = nbd_co_writev, + .bdrv_close = nbd_close, + .bdrv_co_flush_to_os = nbd_co_flush, + .bdrv_co_discard = nbd_co_discard, + .bdrv_getlength = nbd_getlength, +}; + +static BlockDriver bdrv_nbd_unix = { + .format_name = "nbd", + .protocol_name = "nbd+unix", .instance_size = sizeof(BDRVNBDState), .bdrv_file_open = nbd_open, .bdrv_co_readv = nbd_co_readv, @@ -506,12 +598,13 @@ static BlockDriver bdrv_nbd = { .bdrv_co_flush_to_os = nbd_co_flush, .bdrv_co_discard = nbd_co_discard, .bdrv_getlength = nbd_getlength, - .protocol_name = "nbd", }; static void bdrv_nbd_init(void) { bdrv_register(&bdrv_nbd); + bdrv_register(&bdrv_nbd_tcp); + bdrv_register(&bdrv_nbd_unix); } block_init(bdrv_nbd_init); diff --git a/blockdev-nbd.c b/blockdev-nbd.c index 8031813071..d1721a3e26 100644 --- a/blockdev-nbd.c +++ b/blockdev-nbd.c @@ -82,6 +82,11 @@ void qmp_nbd_server_add(const char *device, bool has_writable, bool writable, NBDExport *exp; NBDCloseNotifier *n; + if (server_fd == -1) { + error_setg(errp, "NBD server not running"); + return; + } + if (nbd_export_find(device)) { error_setg(errp, "NBD server already exporting device '%s'", device); return; @@ -93,6 +98,13 @@ void qmp_nbd_server_add(const char *device, bool has_writable, bool writable, return; } + if (!has_writable) { + writable = true; + } + if (bdrv_is_read_only(bs)) { + writable = false; + } + exp = nbd_export_new(bs, 0, -1, writable ? 0 : NBD_FLAG_READ_ONLY, nbd_server_put_ref); @@ -113,7 +125,9 @@ void qmp_nbd_server_stop(Error **errp) nbd_close_notifier(&cn->n, nbd_export_get_blockdev(cn->exp)); } - qemu_set_fd_handler2(server_fd, NULL, NULL, NULL, NULL); - close(server_fd); - server_fd = -1; + if (server_fd != -1) { + qemu_set_fd_handler2(server_fd, NULL, NULL, NULL, NULL); + close(server_fd); + server_fd = -1; + } } diff --git a/hmp-commands.hx b/hmp-commands.hx index f916385c0a..b74ef75c39 100644 --- a/hmp-commands.hx +++ b/hmp-commands.hx @@ -1310,6 +1310,51 @@ Remove all matches from the access control list, and set the default policy back to @code{deny}. ETEXI + { + .name = "nbd_server_start", + .args_type = "all:-a,writable:-w,uri:s", + .params = "nbd_server_start [-a] [-w] host:port", + .help = "serve block devices on the given host and port", + .mhandler.cmd = hmp_nbd_server_start, + }, +STEXI +@item nbd_server_start @var{host}:@var{port} +@findex nbd_server_start +Start an NBD server on the given host and/or port. If the @option{-a} +option is included, all of the virtual machine's block devices that +have an inserted media on them are automatically exported; in this case, +the @option{-w} option makes the devices writable too. +ETEXI + + { + .name = "nbd_server_add", + .args_type = "writable:-w,device:B", + .params = "nbd_server_add [-w] device", + .help = "export a block device via NBD", + .mhandler.cmd = hmp_nbd_server_add, + }, +STEXI +@item nbd_server_add @var{device} +@findex nbd_server_add +Export a block device through QEMU's NBD server, which must be started +beforehand with @command{nbd_server_start}. The @option{-w} option makes the +exported device writable too. +ETEXI + + { + .name = "nbd_server_stop", + .args_type = "", + .params = "nbd_server_stop", + .help = "stop serving block devices using the NBD protocol", + .mhandler.cmd = hmp_nbd_server_stop, + }, +STEXI +@item nbd_server_stop +@findex nbd_server_stop +Stop the QEMU embedded NBD server. +ETEXI + + #if defined(TARGET_I386) { @@ -18,6 +18,7 @@ #include "qemu-option.h" #include "qemu-timer.h" #include "qmp-commands.h" +#include "qemu_socket.h" #include "monitor.h" #include "console.h" @@ -1259,3 +1260,78 @@ void hmp_screen_dump(Monitor *mon, const QDict *qdict) qmp_screendump(filename, &err); hmp_handle_error(mon, &err); } + +void hmp_nbd_server_start(Monitor *mon, const QDict *qdict) +{ + const char *uri = qdict_get_str(qdict, "uri"); + int writable = qdict_get_try_bool(qdict, "writable", 0); + int all = qdict_get_try_bool(qdict, "all", 0); + Error *local_err = NULL; + BlockInfoList *block_list, *info; + SocketAddress *addr; + + if (writable && !all) { + error_setg(&local_err, "-w only valid together with -a"); + goto exit; + } + + /* First check if the address is valid and start the server. */ + addr = socket_parse(uri, &local_err); + if (local_err != NULL) { + goto exit; + } + + qmp_nbd_server_start(addr, &local_err); + qapi_free_SocketAddress(addr); + if (local_err != NULL) { + goto exit; + } + + if (!all) { + return; + } + + /* Then try adding all block devices. If one fails, close all and + * exit. + */ + block_list = qmp_query_block(NULL); + + for (info = block_list; info; info = info->next) { + if (!info->value->has_inserted) { + continue; + } + + qmp_nbd_server_add(info->value->device, true, writable, &local_err); + + if (local_err != NULL) { + qmp_nbd_server_stop(NULL); + break; + } + } + + qapi_free_BlockInfoList(block_list); + +exit: + hmp_handle_error(mon, &local_err); +} + +void hmp_nbd_server_add(Monitor *mon, const QDict *qdict) +{ + const char *device = qdict_get_str(qdict, "device"); + int writable = qdict_get_try_bool(qdict, "writable", 0); + Error *local_err = NULL; + + qmp_nbd_server_add(device, true, writable, &local_err); + + if (local_err != NULL) { + hmp_handle_error(mon, &local_err); + } +} + +void hmp_nbd_server_stop(Monitor *mon, const QDict *qdict) +{ + Error *errp = NULL; + + qmp_nbd_server_stop(&errp); + hmp_handle_error(mon, &errp); +} @@ -77,5 +77,8 @@ void hmp_getfd(Monitor *mon, const QDict *qdict); void hmp_closefd(Monitor *mon, const QDict *qdict); void hmp_send_key(Monitor *mon, const QDict *qdict); void hmp_screen_dump(Monitor *mon, const QDict *qdict); +void hmp_nbd_server_start(Monitor *mon, const QDict *qdict); +void hmp_nbd_server_add(Monitor *mon, const QDict *qdict); +void hmp_nbd_server_stop(Monitor *mon, const QDict *qdict); #endif @@ -596,24 +596,23 @@ int nbd_init(int fd, int csock, uint32_t flags, off_t size, size_t blocksize) return -serrno; } - if (flags & NBD_FLAG_READ_ONLY) { - int read_only = 1; - TRACE("Setting readonly attribute"); - - if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) { + if (ioctl(fd, NBD_SET_FLAGS, flags) < 0) { + if (errno == ENOTTY) { + int read_only = (flags & NBD_FLAG_READ_ONLY) != 0; + TRACE("Setting readonly attribute"); + + if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) { + int serrno = errno; + LOG("Failed setting read-only attribute"); + return -serrno; + } + } else { int serrno = errno; - LOG("Failed setting read-only attribute"); + LOG("Failed setting flags"); return -serrno; } } - if (ioctl(fd, NBD_SET_FLAGS, flags) < 0 - && errno != ENOTTY) { - int serrno = errno; - LOG("Failed setting flags"); - return -serrno; - } - TRACE("Negotiation ended"); return 0; diff --git a/qemu-doc.texi b/qemu-doc.texi index 35cabbcb9e..d8fb2de10e 100644 --- a/qemu-doc.texi +++ b/qemu-doc.texi @@ -610,14 +610,14 @@ QEMU can access directly to block device exported using the Network Block Device protocol. @example -qemu-system-i386 linux.img -hdb nbd:my_nbd_server.mydomain.org:1024 +qemu-system-i386 linux.img -hdb nbd://my_nbd_server.mydomain.org:1024/ @end example If the NBD server is located on the same host, you can use an unix socket instead of an inet socket: @example -qemu-system-i386 linux.img -hdb nbd:unix:/tmp/my_socket +qemu-system-i386 linux.img -hdb nbd+unix://?socket=/tmp/my_socket @end example In this case, the block device must be exported using qemu-nbd: @@ -631,17 +631,26 @@ The use of qemu-nbd allows to share a disk between several guests: qemu-nbd --socket=/tmp/my_socket --share=2 my_disk.qcow2 @end example +@noindent and then you can use it with two guests: @example -qemu-system-i386 linux1.img -hdb nbd:unix:/tmp/my_socket -qemu-system-i386 linux2.img -hdb nbd:unix:/tmp/my_socket +qemu-system-i386 linux1.img -hdb nbd+unix://?socket=/tmp/my_socket +qemu-system-i386 linux2.img -hdb nbd+unix://?socket=/tmp/my_socket @end example -If the nbd-server uses named exports (since NBD 2.9.18), you must use the -"exportname" option: +If the nbd-server uses named exports (supported since NBD 2.9.18, or with QEMU's +own embedded NBD server), you must specify an export name in the URI: @example -qemu-system-i386 -cdrom nbd:localhost:exportname=debian-500-ppc-netinst -qemu-system-i386 -cdrom nbd:localhost:exportname=openSUSE-11.1-ppc-netinst +qemu-system-i386 -cdrom nbd://localhost/debian-500-ppc-netinst +qemu-system-i386 -cdrom nbd://localhost/openSUSE-11.1-ppc-netinst +@end example + +The URI syntax for NBD is supported since QEMU 1.3. An alternative syntax is +also available. Here are some example of the older syntax: +@example +qemu-system-i386 linux.img -hdb nbd:my_nbd_server.mydomain.org:1024 +qemu-system-i386 linux2.img -hdb nbd:unix:/tmp/my_socket +qemu-system-i386 -cdrom nbd:localhost:10809:exportname=debian-500-ppc-netinst @end example @node disk_images_sheepdog diff --git a/qemu-nbd.c b/qemu-nbd.c index 15bcd08123..80f08d8464 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -539,6 +539,7 @@ int main(int argc, char **argv) snprintf(sockpath, 128, SOCKET_PATH, basename(device)); } + qemu_init_main_loop(); bdrv_init(); atexit(bdrv_close_all); @@ -584,7 +585,6 @@ int main(int argc, char **argv) memset(&client_thread, 0, sizeof(client_thread)); } - qemu_init_main_loop(); qemu_set_fd_handler2(fd, nbd_can_accept, nbd_accept, NULL, (void *)(uintptr_t)fd); |