* Version 1.1 - added bs (blocksize) option (Alexey Guzeev, aga@permonline.ru)
* Version 1.2 - I added new option '-d' to send the disconnect request
* Version 2.0 - Version synchronised with server
+ * Version 2.1 - Check for disconnection before INIT_PASSWD is received
+ * to make errormsg a bit more helpful in case the server can't
+ * open the exported file.
*/
-#include <asm/page.h>
+#include "config.h"
+#include "lfs.h"
+
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <fcntl.h>
#include <syslog.h>
#include <stdlib.h>
+#include <sys/mount.h>
+#include <sys/mman.h>
+#include <errno.h>
-#define MY_NAME "nbd_client"
#ifndef __GNUC__
#error I need GCC to work
#endif
#include <linux/ioctl.h>
+#define MY_NAME "nbd_client"
#include "cliserv.h"
-int opennet(char *name, int port)
-{
+int check_conn(char* devname, int do_print) {
+ char buf[256];
+ int fd;
+ int len;
+ if(!strncmp(devname, "/dev/", 5)) {
+ devname+=5;
+ }
+ snprintf(buf, 256, "/sys/block/%s/pid", devname);
+ if((fd=open(buf, O_RDONLY))<0) {
+ if(errno==ENOENT) {
+ return 1;
+ } else {
+ return 2;
+ }
+ }
+ len=read(fd, buf, 256);
+ buf[len-1]='\0';
+ if(do_print) printf("%s\n", buf);
+ return 0;
+}
+
+int opennet(char *name, int port, int sdp) {
int sock;
struct sockaddr_in xaddrin;
int xaddrinlen = sizeof(xaddrin);
struct hostent *hostn;
+ int af;
hostn = gethostbyname(name);
if (!hostn)
err("Gethostname failed: %h\n");
- if ((sock = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)
+ af = AF_INET;
+ if(sdp) {
+#ifdef WITH_SDP
+ af = AF_INET_SDP;
+#else
+ err("Can't do SDP: I was not compiled with SDP support!");
+#endif
+ }
+ if ((sock = socket(af, SOCK_STREAM, IPPROTO_TCP)) < 0)
err("Socket failed: %m");
- xaddrin.sin_family = AF_INET;
+ xaddrin.sin_family = af;
xaddrin.sin_port = htons(port);
xaddrin.sin_addr.s_addr = *((int *) hostn->h_addr);
if ((connect(sock, (struct sockaddr *) &xaddrin, xaddrinlen) < 0))
return sock;
}
-int main(int argc, char *argv[])
-{
- int port, sock, nbd, one = 1;
+void negotiate(int sock, u64 *rsize64, u32 *flags) {
u64 magic, size64;
- unsigned long size;
char buf[256] = "\0\0\0\0\0\0\0\0\0";
- int blocksize=1024;
- char *hostname;
- int swap=0;
-
- logging();
-
- if (argc < 3) {
- errmsg:
- fprintf(stderr, "Usage: nbd-client [bs=blocksize] host port nbd_device [-swap]\n");
- fprintf(stderr, "Or : nbd-client -d nbd_device\n");
- fprintf(stderr, "Default value for blocksize is 1024 (recommended for ethernet)\n");
- fprintf(stderr, "Allowed values for blocksize are 512,1024,2048,4096\n"); /* will be checked in kernel :) */
- fprintf(stderr, "Note, that kernel 2.4.2 and older ones do not work correctly with\n");
- fprintf(stderr, "blocksizes other than 1024 without patches\n");
- return 1;
- }
-
- ++argv; --argc; /* skip programname */
-
- if (strcmp(argv[0], "-d")==0) {
- nbd = open(argv[1], O_RDWR);
- if (nbd < 0)
- err("Can not open NBD: %m");
- printf("Disconnecting: que, ");
- if (ioctl(nbd, NBD_CLEAR_QUE)< 0)
- err("Ioctl failed: %m\n");
- printf("disconnect, ");
-#ifdef NBD_DISCONNECT
- if (ioctl(nbd, NBD_DISCONNECT)<0)
- err("Ioctl failed: %m\n");
- printf("sock, ");
-#else
- fprintf(stderr, "Can't disconnect: I was not compiled with disconnect support!\n" );
- exit(1);
-#endif
- if (ioctl(nbd, NBD_CLEAR_SOCK)<0)
- err("Ioctl failed: %m\n");
- printf("done\n");
- return 0;
- }
-
- if (strncmp(argv[0], "bs=", 3)==0) {
- blocksize=atoi(argv[0]+3);
- ++argv; --argc; /* skip blocksize */
- }
-
- if (argc==0) goto errmsg;
- hostname=argv[0];
- ++argv; --argc; /* skip hostname */
-
- if (argc==0) goto errmsg;
- port = atoi(argv[0]);
- ++argv; --argc; /* skip port */
-
- if (argc==0) goto errmsg;
- sock = opennet(hostname, port);
- nbd = open(argv[0], O_RDWR);
- if (nbd < 0)
- err("Can not open NBD: %m");
- ++argv; --argc; /* skip device */
-
- if (argc>1) goto errmsg;
- if (argc!=0) swap=1;
- argv=NULL; argc=0; /* don't use it later suddenly */
printf("Negotiation: ");
if (read(sock, buf, 8) < 0)
err("Failed/1: %m");
+ if (strlen(buf)==0)
+ err("Server closed connection");
if (strcmp(buf, INIT_PASSWD))
err("INIT_PASSWD bad");
printf(".");
printf("size = %lu", (unsigned long)(size64));
#endif
- if (read(sock, &buf, 128) < 0)
+ if (read(sock, flags, sizeof(*flags)) < 0)
err("Failed/4: %m\n");
+ *flags = ntohl(*flags);
+
+ if (read(sock, &buf, 124) < 0)
+ err("Failed/5: %m\n");
printf("\n");
+ *rsize64 = size64;
+}
+
+void setsizes(int nbd, u64 size64, int blocksize, u32 flags) {
+ unsigned long size;
+ int read_only = (flags & NBD_FLAG_READ_ONLY) ? 1 : 0;
+
#ifdef NBD_SET_SIZE_BLOCKS
if (size64/blocksize > (~0UL >> 1))
err("Device too large.\n");
size = (unsigned long)(size64/blocksize);
if ((er = ioctl(nbd, NBD_SET_SIZE_BLOCKS, size)) < 0)
err("Ioctl/1.1b failed: %m\n");
-fprintf(stderr, "bs=%d, sz=%lu\n", blocksize, size);
+ fprintf(stderr, "bs=%d, sz=%lu\n", blocksize, size);
}
#else
if (size64 > (~0UL >> 1)) {
} else {
size = (unsigned long)size64;
if (ioctl(nbd, NBD_SET_SIZE, size) < 0)
- err("Ioctl/1 failed: %m\n");
+ err("Ioctl NBD_SET_SIZE failed: %m\n");
}
#endif
ioctl(nbd, NBD_CLEAR_SOCK);
+
+ if (ioctl(nbd, BLKROSET, (unsigned long) &read_only) < 0)
+ err("Unable to set read-only attribute for device");
+}
+
+void set_timeout(int nbd, int timeout) {
+#ifdef NBD_SET_TIMEOUT
+ if (timeout) {
+ if (ioctl(nbd, NBD_SET_TIMEOUT, (unsigned long)timeout) < 0)
+ err("Ioctl NBD_SET_TIMEOUT failed: %m\n");
+ fprintf(stderr, "timeout=%d\n", timeout);
+ }
+#endif
+}
+
+void finish_sock(int sock, int nbd, int swap) {
if (ioctl(nbd, NBD_SET_SOCK, sock) < 0)
- err("Ioctl/2 failed: %m\n");
+ err("Ioctl NBD_SET_SOCK failed: %m\n");
+/*
+ * If anyone ever forward-patches this patch, I'll happily re-enable
+ * this code. Until then...
#ifndef SO_SWAPPING
if (swap)
err("You have to compile me on machine with swapping patch enabled in order to use it later.");
#else
if (swap)
if (setsockopt(sock, SOL_SOCKET, SO_SWAPPING, &one, sizeof(int)) < 0)
- err("Could not enable swapping: %m");
+ err("Could not enable swapping: %m");
#endif
+*/
+ mlockall(MCL_CURRENT | MCL_FUTURE);
+}
- /* Go daemon */
+int main(int argc, char *argv[]) {
+ int port, sock, nbd;
+ int blocksize=1024;
+ char *hostname, *nbddev;
+ int swap=0;
+ int cont=0;
+ int timeout=0;
+ int sdp=0;
+ u64 size64;
+ u32 flags;
+
+ logging();
+
+ if (argc < 3) {
+ errmsg:
+ fprintf(stderr, "nbd-client version %s\n", PACKAGE_VERSION);
+ fprintf(stderr, "Usage: nbd-client [bs=blocksize] [timeout=sec] host port nbd_device [-swap] [-persist]\n");
+ fprintf(stderr, "Or : nbd-client -d nbd_device\n");
+ fprintf(stderr, "Or : nbd-client -c nbd_device\n");
+ fprintf(stderr, "Default value for blocksize is 1024 (recommended for ethernet)\n");
+ fprintf(stderr, "Allowed values for blocksize are 512,1024,2048,4096\n"); /* will be checked in kernel :) */
+ fprintf(stderr, "Note, that kernel 2.4.2 and older ones do not work correctly with\n");
+ fprintf(stderr, "blocksizes other than 1024 without patches\n");
+ return 1;
+ }
+
+ ++argv; --argc; /* skip programname */
+ if (strcmp(argv[0], "-d")==0) {
+ nbd = open(argv[1], O_RDWR);
+ if (nbd < 0)
+ err("Can not open NBD: %m");
+ printf("Disconnecting: que, ");
+ if (ioctl(nbd, NBD_CLEAR_QUE)< 0)
+ err("Ioctl failed: %m\n");
+ printf("disconnect, ");
+#ifdef NBD_DISCONNECT
+ if (ioctl(nbd, NBD_DISCONNECT)<0)
+ err("Ioctl failed: %m\n");
+ printf("sock, ");
+#else
+ fprintf(stderr, "Can't disconnect: I was not compiled with disconnect support!\n" );
+ exit(1);
+#endif
+ if (ioctl(nbd, NBD_CLEAR_SOCK)<0)
+ err("Ioctl failed: %m\n");
+ printf("done\n");
+ return 0;
+ }
+ if(strcmp(argv[0], "-c")==0) {
+ return check_conn(argv[1], 1);
+ }
+
+ if (strncmp(argv[0], "bs=", 3)==0) {
+ blocksize=atoi(argv[0]+3);
+ ++argv; --argc; /* skip blocksize */
+ }
+
+ if (strncmp(argv[0], "timeout=", 8)==0) {
+ timeout=atoi(argv[0]+8);
+ ++argv; --argc; /* skip timeout */
+ }
+
+ if (argc==0) goto errmsg;
+ hostname=argv[0];
+ ++argv; --argc; /* skip hostname */
+
+ if (argc==0) goto errmsg;
+ port = atoi(argv[0]);
+ ++argv; --argc; /* skip port */
+
+ if (argc==0) goto errmsg;
+ nbddev = argv[0];
+ nbd = open(nbddev, O_RDWR);
+ if (nbd < 0)
+ err("Can not open NBD: %m");
+ ++argv; --argc; /* skip device */
+
+ if (argc>3) goto errmsg;
+ if (argc) {
+ if(strncmp(argv[0], "-swap", 5)==0) {
+ swap=1;
+ ++argv;--argc;
+ }
+ }
+ if (argc) {
+ if(strncmp(argv[0], "-persist", 8)==0) {
+ cont=1;
+ ++argv;--argc;
+ }
+ }
+ if (argc) {
+ if(strncmp(argv[0], "-sdp", 4)==0) {
+ sdp=1;
+ ++argv;--argc;
+ }
+ }
+ if(argc) goto errmsg;
+ sock = opennet(hostname, port, sdp);
+ argv=NULL; argc=0; /* don't use it later suddenly */
+
+ negotiate(sock, &size64, &flags);
+ setsizes(nbd, size64, blocksize, flags);
+ set_timeout(nbd, timeout);
+ finish_sock(sock, nbd, swap);
+
+ /* Go daemon */
+
chdir("/");
- if (fork())
- exit(0);
+ do {
+#ifndef NOFORK
+ if (fork()) {
+ while(check_conn(nbddev, 0)) {
+ sleep(1);
+ }
+ open(nbddev, O_RDONLY);
+ exit(0);
+ }
+#endif
+
+ if (ioctl(nbd, NBD_DO_IT) < 0) {
+ fprintf(stderr, "Kernel call returned: %m");
+ if(errno==EBADR) {
+ /* The user probably did 'nbd-client -d' on us.
+ * quit */
+ cont=0;
+ } else {
+ if(cont) {
+ u64 new_size;
+ u32 new_flags;
+
+ fprintf(stderr, " Reconnecting\n");
+ close(sock); close(nbd);
+ sock = opennet(hostname, port, sdp);
+ nbd = open(nbddev, O_RDWR);
+ negotiate(sock, &new_size, &new_flags);
+ if (size64 != new_size) {
+ err("Size of the device changed. Bye");
+ }
+ setsizes(nbd, size64, blocksize,
+ new_flags);
- if (ioctl(nbd, NBD_DO_IT) < 0)
- fprintf(stderr, "Kernel call returned: %m");
- else
- fprintf(stderr, "Kernel call returned.");
+ set_timeout(nbd, timeout);
+ finish_sock(sock,nbd,swap);
+ }
+ }
+ } else {
+ /* We're on 2.4. It's not clearly defined what exactly
+ * happened at this point. Probably best to quit, now
+ */
+ fprintf(stderr, "Kernel call returned.");
+ cont=0;
+ }
+ } while(cont);
printf("Closing: que, ");
ioctl(nbd, NBD_CLEAR_QUE);
printf("sock, ");
projects / nbd.git / blobdiff