From 1d7d2a9d2191c34bd1ad69b420db9b47faa3fb8c Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Sun, 4 Nov 2012 13:04:24 +0100 Subject: [PATCH] nbd: accept URIs The URI syntax is consistent with the Gluster syntax. Export names are specified in the path, preceded by one or more (otherwise unused) slashes. Signed-off-by: Paolo Bonzini --- block/nbd.c | 98 ++++++++++++++++++++++++++++++++++++++++++++++++++- qemu-doc.texi | 25 ++++++++----- 2 files changed, 114 insertions(+), 9 deletions(-) diff --git a/block/nbd.c b/block/nbd.c index 48bbecacaf..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" @@ -69,6 +70,69 @@ typedef struct BDRVNBDState { char *export_name; /* An NBD server may export several devices */ } BDRVNBDState; +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; @@ -77,6 +141,10 @@ static int nbd_config(BDRVNBDState *s, const char *filename) 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); @@ -495,6 +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, @@ -503,12 +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/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