Re: [PATCH] nbd-client: support newstyle protocol, -b, -d
On Wed, 24 Oct 2018 15:53:44 +0200 Denys Vlasenko wrote: > I applied a modified version of the patch, > please let me know whether it works. > Thanks! It does, both on x86_64 and MIPS64be, with old and new servers. Thank you! ___ busybox mailing list busybox@busybox.net http://lists.busybox.net/mailman/listinfo/busybox
Re: [PATCH] nbd-client: support newstyle protocol, -b, -d
Apologies for the delay.
On Tue, Oct 9, 2018 at 1:42 AM Elvira Khabirova
wrote:
> Recognize the "newstyle" protocol and switch to it automatically.
> Add options for setting blocksize (-b) and for disconnecting
> a nbd device (-d).
>
> Signed-off-by: Elvira Khabirova
> ---
> networking/nbd-client.c | 168 +---
> 1 file changed, 140 insertions(+), 28 deletions(-)
>
> diff --git a/networking/nbd-client.c b/networking/nbd-client.c
> index bedb01a1c..9e718ff93 100644
> --- a/networking/nbd-client.c
> +++ b/networking/nbd-client.c
> @@ -27,17 +27,17 @@
> #define NBD_SET_SIZE_BLOCKS _IO(0xab, 7)
> #define NBD_DISCONNECT_IO(0xab, 8)
> #define NBD_SET_TIMEOUT _IO(0xab, 9)
> +#define NBD_SET_FLAGS _IO(0xab, 10)
>
> //usage:#define nbdclient_trivial_usage
> -//usage: "HOST PORT BLOCKDEV"
> +//usage: "{ [-b BLKSIZE] [-N name] HOST PORT | -d } BLOCKDEV"
> //usage:#define nbdclient_full_usage "\n\n"
> //usage: "Connect to HOST and provide a network block device on
> BLOCKDEV"
>
> //TODO: more compat with nbd-client version 2.9.13 -
> //Usage: nbd-client [bs=blocksize] [timeout=sec] host port nbd_device
> [-swap] [-persist] [-nofork]
> -//Or : nbd-client -d nbd_device
> //Or : nbd-client -c nbd_device
> -//Default value for blocksize is 1024 (recommended for ethernet)
> +//Default value for blocksize is 4096
> //Allowed values for blocksize are 512,1024,2048,4096
> //Note, that kernel 2.4.2 and older ones do not work correctly with
> //blocksizes other than 1024 without patches
> @@ -45,37 +45,90 @@
> int nbdclient_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
> int nbdclient_main(int argc UNUSED_PARAM, char **argv)
> {
> - unsigned long timeout = 0;
> #if BB_MMU
> int nofork = 0;
> #endif
> - char *host, *port, *device;
> + char *host, *port, *device, *name;
> + unsigned blksize, size_blocks;
> + unsigned timeout;
> + unsigned opt;
> +
> + uint16_t handshake_flags;
> + uint32_t client_flags = 0;
> +
> struct nbd_header_t {
> uint64_t magic1; // "NBDMAGIC"
> - uint64_t magic2; // 0x420281861253 big endian
> + uint64_t magic2; // old style: 0x420281861253 big endian
> +// new style: 0x49484156454F5054 (IHAVEOPT)
> + } nbd_header;
> +
> + struct old_nbd_header_t {
> uint64_t devsize;
> uint32_t flags;
> char data[124];
> - } nbd_header;
> + } old_nbd_header;
>
> - BUILD_BUG_ON(offsetof(struct nbd_header_t, data) != 8+8+8+4);
> + struct new_nbd_header_t {
> + uint64_t devsize;
> + uint16_t transmission_flags;
> + char data[124];
> + } new_nbd_header;
>
> - // Parse command line stuff (just a stub now)
> - if (!argv[1] || !argv[2] || !argv[3] || argv[4])
> - bb_show_usage();
> + struct nbd_opt_t {
> + uint64_t magic;
> + uint32_t opt;
> + uint32_t len;
> + } nbd_opts;
> +
> + BUILD_BUG_ON(offsetof(struct old_nbd_header_t, data) != 8+4);
> + BUILD_BUG_ON(offsetof(struct new_nbd_header_t, data) != 8+2);
>
> #if !BB_MMU
> bb_daemonize_or_rexec(DAEMON_CLOSE_EXTRA_FDS, argv);
> #endif
>
> - host = argv[1];
> - port = argv[2];
> - device = argv[3];
> + // Parse args
> + opt = getopt32(argv, "b:+t:+N:d", , , );
-t is not documented in --help.
Many man pages list only long options, a-la:
SYNOPSIS
nbd-client host [ port ] nbd-device [ -connections num ] [ -sdp ] [ -swap ]
[ -persist ] [ -nofork ] [ -nonetlink ] [ -systemd-mark ] [
-block-size block size ]
[ -timeout seconds ] [ -name name ] [ -certfile certfile ] [
-keyfile keyfile ]
[ -cacertfile cacertfile ] [ -tlshostname hostname ]
nbd-client nbd-device
nbd-client -d nbd-device
nbd-client -c nbd-device
nbd-client -l host [ port ]
nbd-client [ -netlink ] -l host
Because of this, I assume a lot of scripts would use long opts :/
We probably much better if we accept long opts.
> + if (!(opt & 0x1)) {
> + blksize = 4096;
> + }
> +
> + if (!(opt & 0x2)) {
> + timeout = 0;
> + }
> +
> + if (!(opt & 0x4)) {
> + name = NULL;
> + }
Assign the values unconditionally before option parsing. Less generated code.
> + nbd_opts.len = htonl(strlen(name));
> + xwrite(sock, _opts,
> + sizeof(nbd_opts.magic) +
> + sizeof(nbd_opts.opt) +
> + sizeof(nbd_opts.len));
> + xwrite(sock, name, strlen(name));
two times strlen()...
I applied a modified version of the patch,
please
Re: [PATCH] nbd-client: support newstyle protocol, -b, -d
On Tue, 9 Oct 2018 01:41:48 +0200 Elvira Khabirova wrote: > Recognize the "newstyle" protocol and switch to it automatically. > Add options for setting blocksize (-b) and for disconnecting > a nbd device (-d). Ping. Support for oldstyle protocol was dropped in nbd-server v3.10, which was released in 2015. I tested this patch both with an old (3.8) and a new (3.18) server. ___ busybox mailing list busybox@busybox.net http://lists.busybox.net/mailman/listinfo/busybox
[PATCH] nbd-client: support newstyle protocol, -b, -d
Recognize the "newstyle" protocol and switch to it automatically.
Add options for setting blocksize (-b) and for disconnecting
a nbd device (-d).
Signed-off-by: Elvira Khabirova
---
networking/nbd-client.c | 168 +---
1 file changed, 140 insertions(+), 28 deletions(-)
diff --git a/networking/nbd-client.c b/networking/nbd-client.c
index bedb01a1c..9e718ff93 100644
--- a/networking/nbd-client.c
+++ b/networking/nbd-client.c
@@ -27,17 +27,17 @@
#define NBD_SET_SIZE_BLOCKS _IO(0xab, 7)
#define NBD_DISCONNECT_IO(0xab, 8)
#define NBD_SET_TIMEOUT _IO(0xab, 9)
+#define NBD_SET_FLAGS _IO(0xab, 10)
//usage:#define nbdclient_trivial_usage
-//usage: "HOST PORT BLOCKDEV"
+//usage: "{ [-b BLKSIZE] [-N name] HOST PORT | -d } BLOCKDEV"
//usage:#define nbdclient_full_usage "\n\n"
//usage: "Connect to HOST and provide a network block device on BLOCKDEV"
//TODO: more compat with nbd-client version 2.9.13 -
//Usage: nbd-client [bs=blocksize] [timeout=sec] host port nbd_device [-swap]
[-persist] [-nofork]
-//Or : nbd-client -d nbd_device
//Or : nbd-client -c nbd_device
-//Default value for blocksize is 1024 (recommended for ethernet)
+//Default value for blocksize is 4096
//Allowed values for blocksize are 512,1024,2048,4096
//Note, that kernel 2.4.2 and older ones do not work correctly with
//blocksizes other than 1024 without patches
@@ -45,37 +45,90 @@
int nbdclient_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int nbdclient_main(int argc UNUSED_PARAM, char **argv)
{
- unsigned long timeout = 0;
#if BB_MMU
int nofork = 0;
#endif
- char *host, *port, *device;
+ char *host, *port, *device, *name;
+ unsigned blksize, size_blocks;
+ unsigned timeout;
+ unsigned opt;
+
+ uint16_t handshake_flags;
+ uint32_t client_flags = 0;
+
struct nbd_header_t {
uint64_t magic1; // "NBDMAGIC"
- uint64_t magic2; // 0x420281861253 big endian
+ uint64_t magic2; // old style: 0x420281861253 big endian
+// new style: 0x49484156454F5054 (IHAVEOPT)
+ } nbd_header;
+
+ struct old_nbd_header_t {
uint64_t devsize;
uint32_t flags;
char data[124];
- } nbd_header;
+ } old_nbd_header;
- BUILD_BUG_ON(offsetof(struct nbd_header_t, data) != 8+8+8+4);
+ struct new_nbd_header_t {
+ uint64_t devsize;
+ uint16_t transmission_flags;
+ char data[124];
+ } new_nbd_header;
- // Parse command line stuff (just a stub now)
- if (!argv[1] || !argv[2] || !argv[3] || argv[4])
- bb_show_usage();
+ struct nbd_opt_t {
+ uint64_t magic;
+ uint32_t opt;
+ uint32_t len;
+ } nbd_opts;
+
+ BUILD_BUG_ON(offsetof(struct old_nbd_header_t, data) != 8+4);
+ BUILD_BUG_ON(offsetof(struct new_nbd_header_t, data) != 8+2);
#if !BB_MMU
bb_daemonize_or_rexec(DAEMON_CLOSE_EXTRA_FDS, argv);
#endif
- host = argv[1];
- port = argv[2];
- device = argv[3];
+ // Parse args
+ opt = getopt32(argv, "b:+t:+N:d", , , );
+ argv += optind;
+
+ if (opt & 0x8) {
+ if (argv[0]) {
+ int nbd = xopen(argv[0], O_RDWR);
+ ioctl(nbd, NBD_DISCONNECT);
+ ioctl(nbd, NBD_CLEAR_SOCK);
+ close(nbd);
+ return 0;
+ } else {
+ bb_show_usage();
+ }
+ }
+
+ if (!(opt & 0x1)) {
+ blksize = 4096;
+ }
+
+ if (!(opt & 0x2)) {
+ timeout = 0;
+ }
+
+ if (!(opt & 0x4)) {
+ name = NULL;
+ }
+
+ if (!argv[0] || !argv[1] || !argv[2] || argv[3]) {
+ bb_show_usage();
+ }
+
+ host = argv[0];
+ port = argv[1];
+ device = argv[2];
// Repeat until spanked (-persist behavior)
for (;;) {
int sock, nbd;
int ro;
+ int protover; // 0 for old, 1 for new
+ char *data;
// Make sure the /dev/nbd exists
nbd = xopen(device, O_RDWR);
@@ -85,25 +138,84 @@ int nbdclient_main(int argc UNUSED_PARAM, char **argv)
setsockopt_1(sock, IPPROTO_TCP, TCP_NODELAY);
// Log on to the server
- xread(sock, _header, 8+8+8+4 + 124);
- if (memcmp(_header.magic1,
"NBDMAGIC""\x00\x00\x42\x02\x81\x86\x12\x53", 16) != 0)
+ xread(sock, _header, 8+8);
+ if (memcmp(_header.magic1, "NBDMAGIC",
+ sizeof(nbd_header.magic1)) != 0
+ ) {
+ bb_error_msg_and_die("login failed");
+ }
+
+
