r288: Don't forget to kill nbd-server the second time; thanks to Patrice Dumas

[nbd.git] / nbd-client.c

diff --git a/nbd-client.c b/nbd-client.c
index 02dce78..d03b568 100644 (file)
--- a/nbd-client.c
+++ b/nbd-client.c
@@ -16,7 +16,6 @@
 #include "config.h"
 #include "lfs.h"
 
-#include <asm/page.h>
 #include <sys/ioctl.h>
 #include <sys/socket.h>
 #include <sys/types.h>
@@ -28,6 +27,7 @@
 #include <fcntl.h>
 #include <syslog.h>
 #include <stdlib.h>
+#include <sys/mount.h>
 
 #ifndef __GNUC__
 #error I need GCC to work
@@ -60,7 +60,7 @@ int opennet(char *name, int port) {
        return sock;
 }
 
-u64 negotiate(int sock, int blocksize) {
+void negotiate(int sock, u64 *rsize64, u32 *flags) {
        u64 magic, size64;
        char buf[256] = "\0\0\0\0\0\0\0\0\0";
 
@@ -97,15 +97,20 @@ u64 negotiate(int sock, int blocksize) {
                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");
 
-       return size64;
+       *rsize64 = size64;
 }
 
-void setsizes(int nbd, u64 size64, int blocksize) {
+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))
@@ -130,6 +135,19 @@ void setsizes(int nbd, u64 size64, int blocksize) {
 #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) {
@@ -152,14 +170,16 @@ int main(int argc, char *argv[]) {
        char *hostname, *nbddev;
        int swap=0;
        int cont=0;
+       int timeout=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] host port nbd_device [-swap] [-persist]\n");
+               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, "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 :) */
@@ -197,6 +217,11 @@ int main(int argc, char *argv[]) {
                ++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 */
@@ -228,8 +253,9 @@ int main(int argc, char *argv[]) {
        }
        argv=NULL; argc=0; /* don't use it later suddenly */
 
-       size64 = negotiate(sock, blocksize);
-       setsizes(nbd, size64, blocksize);
+       negotiate(sock, &size64, &flags);
+       setsizes(nbd, size64, blocksize, flags);
+       set_timeout(nbd, timeout);
        finish_sock(sock, nbd, swap);
 
        /* Go daemon */
@@ -249,14 +275,21 @@ int main(int argc, char *argv[]) {
                                cont=0;
                        } else {
                                if(cont) {
+                                       u64 new_size;
+                                       u32 new_flags;
+
                                        fprintf(stderr, " Reconnecting\n");
                                        close(sock); close(nbd);
                                        sock = opennet(hostname, port);
                                        nbd = open(nbddev, O_RDWR);
-                                       if(size64!=negotiate(sock,blocksize)) {
+                                       negotiate(sock, &new_size, &new_flags);
+                                       if (size64 != new_size) {
                                                err("Size of the device changed. Bye");
                                        }
-                                       setsizes(nbd, size64, blocksize);
+                                       setsizes(nbd, size64, blocksize,
+                                                               new_flags);
+
+                                       set_timeout(nbd, timeout);
                                        finish_sock(sock,nbd,swap);
                                }
                        }