qemu-nbd tool (Anthony Liguori)

git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4596 c046a42c-6fe2-441c-8c8c-71466251a162

Makefile

@@ -17,7 +17,7 @@ ifdef CONFIG_STATIC
 LDFLAGS += -static
 endif
 ifdef BUILD_DOCS
-DOCS=qemu-doc.html qemu-tech.html qemu.1 qemu-img.1
+DOCS=qemu-doc.html qemu-tech.html qemu.1 qemu-img.1 qemu-nbd.8
 else
 DOCS=
 endif
@@ -159,6 +159,10 @@ qemu-img-%.o: %.c
 %.o: %.c
 	$(CC) $(CFLAGS) $(CPPFLAGS) -c -o $@ $<
 
+qemu-nbd$(EXESUF):  qemu-nbd.o nbd.o qemu-img-block.o \
+		    $(QEMU_IMG_BLOCK_OBJS)
+	$(CC) $(LDFLAGS) -o $@ $^ -lz $(LIBS)
+
 # dyngen host tool
 dyngen$(EXESUF): dyngen.c
 	$(HOST_CC) $(CFLAGS) $(CPPFLAGS) -o $@ $^
@@ -191,6 +195,8 @@ install-doc: $(DOCS)
 ifndef CONFIG_WIN32
 	mkdir -p "$(DESTDIR)$(mandir)/man1"
 	$(INSTALL) qemu.1 qemu-img.1 "$(DESTDIR)$(mandir)/man1"
+	mkdir -p "$(DESTDIR)$(mandir)/man8"
+	$(INSTALL) qemu-nbd.8 "$(DESTDIR)$(mandir)/man8"
 endif
 
 install: all $(if $(BUILD_DOCS),install-doc)
@@ -244,6 +250,10 @@ qemu-img.1: qemu-img.texi
 	$(SRC_PATH)/texi2pod.pl $< qemu-img.pod
 	pod2man --section=1 --center=" " --release=" " qemu-img.pod > $@
 
+qemu-nbd.8: qemu-nbd.texi
+	$(SRC_PATH)/texi2pod.pl $< qemu-nbd.pod
+	pod2man --section=8 --center=" " --release=" " qemu-nbd.pod > $@
+
 info: qemu-doc.info qemu-tech.info
 
 dvi: qemu-doc.dvi qemu-tech.dvi
@@ -296,6 +306,7 @@ tarbin:
         $(bindir)/qemu-sh4eb \
         $(bindir)/qemu-cris \
         $(bindir)/qemu-img \
+        $(bindir)/qemu-nbd \
 	$(datadir)/bios.bin \
 	$(datadir)/vgabios.bin \
 	$(datadir)/vgabios-cirrus.bin \
@@ -309,6 +320,7 @@ tarbin:
 	$(docdir)/qemu-doc.html \
 	$(docdir)/qemu-tech.html \
 	$(mandir)/man1/qemu.1 $(mandir)/man1/qemu-img.1
+	$(mandir)/man8/qemu-nbd.8
 
 # Include automatically generated dependency files
 -include $(wildcard *.d audio/*.d slirp/*.d)

configure

@@ -1105,6 +1105,9 @@ echo "#define CONFIG_UNAME_RELEASE \"$uname_release\"" >> $config_h
 tools=
 if test `expr "$target_list" : ".*softmmu.*"` != 0 ; then
   tools="qemu-img\$(EXESUF) $tools"
+  if [ "$linux" = "yes" ] ; then
+      tools="qemu-nbd\$(EXESUF) $tools"
+  fi
 fi
 echo "TOOLS=$tools" >> $config_mak
 

exec-all.h

@@ -126,7 +126,7 @@ static inline int tlb_set_page(CPUState *env1, target_ulong vaddr,
 #define CODE_GEN_BUFFER_SIZE     (6 * 1024 * 1024)
 #else
 /* XXX: make it dynamic on x86 */
-#define CODE_GEN_BUFFER_SIZE     (16 * 1024 * 1024)
+#define CODE_GEN_BUFFER_SIZE     (64 * 1024 * 1024)
 #endif
 
 //#define CODE_GEN_BUFFER_SIZE     (128 * 1024)

nbd.h

@@ -0,0 +1,37 @@
+/*\
+ *  Copyright (C) 2005  Anthony Liguori <anthony@codemonkey.ws>
+ *
+ *  Network Block Device
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; under version 2 of the License.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+\*/
+
+#ifndef NBD_H
+#define NBD_H
+
+#include <sys/types.h>
+#include <stdbool.h>
+
+#include <qemu-common.h>
+#include "block_int.h"
+
+int tcp_socket_incoming(const char *address, uint16_t port);
+
+int nbd_negotiate(BlockDriverState *bs, int csock, off_t size);
+int nbd_receive_negotiate(int fd, int csock);
+int nbd_trip(BlockDriverState *bs, int csock, off_t size, uint64_t dev_offset, off_t *offset, bool readonly);
+int nbd_client(int fd, int csock);
+int nbd_disconnect(int fd);
+
+#endif

qemu-nbd.c

@@ -0,0 +1,275 @@
+/*\
+ *  Copyright (C) 2005  Anthony Liguori <anthony@codemonkey.ws>
+ *
+ *  Network Block Device
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; under version 2 of the License.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <qemu-common.h>
+#include "block_int.h"
+#include "nbd.h"
+
+#include <malloc.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <getopt.h>
+#include <err.h>
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <netinet/tcp.h>
+#include <arpa/inet.h>
+
+int verbose;
+
+static void usage(const char *name)
+{
+    printf(
+"Usage: %s [OPTIONS] FILE\n"
+"QEMU Disk Network Block Device Server\n"
+"\n"
+"  -p, --port=PORT      port to listen on (default `1024')\n"
+"  -o, --offset=OFFSET  offset into the image\n"
+"  -b, --bind=IFACE     interface to bind to (default `0.0.0.0')\n"
+"  -r, --read-only      export read-only\n"
+"  -P, --partition=NUM  only expose partition NUM\n"
+"  -v, --verbose        display extra debugging information\n"
+"  -h, --help           display this help and exit\n"
+"  -V, --version        output version information and exit\n"
+"\n"
+"Report bugs to <anthony@codemonkey.ws>\n"
+    , name);
+}
+
+static void version(const char *name)
+{
+    printf(
+"qemu-nbd version 0.0.1\n"
+"Written by Anthony Liguori.\n"
+"\n"
+"Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>.\n"
+"This is free software; see the source for copying conditions.  There is NO\n"
+"warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
+    );
+}
+
+struct partition_record
+{
+    uint8_t bootable;
+    uint8_t start_head;
+    uint32_t start_cylinder;
+    uint8_t start_sector;
+    uint8_t system;
+    uint8_t end_head;
+    uint8_t end_cylinder;
+    uint8_t end_sector;
+    uint32_t start_sector_abs;
+    uint32_t nb_sectors_abs;
+};
+
+static void read_partition(uint8_t *p, struct partition_record *r)
+{
+    r->bootable = p[0];
+    r->start_head = p[1];
+    r->start_cylinder = p[3] | ((p[2] << 2) & 0x0300);
+    r->start_sector = p[2] & 0x3f;
+    r->system = p[4];
+    r->end_head = p[5];
+    r->end_cylinder = p[7] | ((p[6] << 2) & 0x300);
+    r->end_sector = p[6] & 0x3f;
+    r->start_sector_abs = p[8] | p[9] << 8 | p[10] << 16 | p[11] << 24;
+    r->nb_sectors_abs = p[12] | p[13] << 8 | p[14] << 16 | p[15] << 24;
+}
+
+static int find_partition(BlockDriverState *bs, int partition,
+                          off_t *offset, off_t *size)
+{
+    struct partition_record mbr[4];
+    uint8_t data[512];
+    int i;
+    int ext_partnum = 4;
+
+    if (bdrv_read(bs, 0, data, 1))
+        errx(EINVAL, "error while reading");
+
+    if (data[510] != 0x55 || data[511] != 0xaa) {
+        errno = -EINVAL;
+        return -1;
+    }
+
+    for (i = 0; i < 4; i++) {
+        read_partition(&data[446 + 16 * i], &mbr[i]);
+
+        if (!mbr[i].nb_sectors_abs)
+            continue;
+
+        if (mbr[i].system == 0xF || mbr[i].system == 0x5) {
+            struct partition_record ext[4];
+            uint8_t data1[512];
+            int j;
+
+            if (bdrv_read(bs, mbr[i].start_sector_abs, data1, 1))
+                errx(EINVAL, "error while reading");
+
+            for (j = 0; j < 4; j++) {
+                read_partition(&data1[446 + 16 * j], &ext[j]);
+                if (!ext[j].nb_sectors_abs)
+                    continue;
+
+                if ((ext_partnum + j + 1) == partition) {
+                    *offset = (uint64_t)ext[j].start_sector_abs << 9;
+                    *size = (uint64_t)ext[j].nb_sectors_abs << 9;
+                    return 0;
+                }
+            }
+            ext_partnum += 4;
+        } else if ((i + 1) == partition) {
+            *offset = (uint64_t)mbr[i].start_sector_abs << 9;
+            *size = (uint64_t)mbr[i].nb_sectors_abs << 9;
+            return 0;
+        }
+    }
+
+    errno = -ENOENT;
+    return -1;
+}
+
+int main(int argc, char **argv)
+{
+    BlockDriverState *bs;
+    off_t dev_offset = 0;
+    off_t offset = 0;
+    bool readonly = false;
+    const char *bindto = "0.0.0.0";
+    int port = 1024;
+    int sock, csock;
+    struct sockaddr_in addr;
+    socklen_t addr_len = sizeof(addr);
+    off_t fd_size;
+    const char *sopt = "hVbo:p:rsP:v";
+    struct option lopt[] = {
+        { "help", 0, 0, 'h' },
+        { "version", 0, 0, 'V' },
+        { "bind", 1, 0, 'b' },
+        { "port", 1, 0, 'p' },
+        { "offset", 1, 0, 'o' },
+        { "read-only", 0, 0, 'r' },
+        { "partition", 1, 0, 'P' },
+        { "snapshot", 0, 0, 's' },
+        { "verbose", 0, 0, 'v' },
+    };
+    int ch;
+    int opt_ind = 0;
+    int li;
+    char *end;
+    bool snapshot = false;
+    int partition = -1;
+
+    while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) {
+        switch (ch) {
+        case 's':
+            snapshot = true;
+            break;
+        case 'b':
+            bindto = optarg;
+            break;
+        case 'p':
+            li = strtol(optarg, &end, 0);
+            if (*end) {
+                errx(EINVAL, "Invalid port `%s'", optarg);
+            }
+            if (li < 1 || li > 65535) {
+                errx(EINVAL, "Port out of range `%s'", optarg);
+            }
+            port = (uint16_t)li;
+            break;
+        case 'o':
+                dev_offset = strtoll (optarg, &end, 0);
+            if (*end) {
+                errx(EINVAL, "Invalid offset `%s'", optarg);
+            }
+            if (dev_offset < 0) {
+                errx(EINVAL, "Offset must be positive `%s'", optarg);
+            }
+            break;
+        case 'r':
+            readonly = true;
+            break;
+        case 'P':
+            partition = strtol(optarg, &end, 0);
+            if (*end)
+                errx(EINVAL, "Invalid partition `%s'", optarg);
+            if (partition < 1 || partition > 8)
+                errx(EINVAL, "Invalid partition %d", partition);
+            break;
+        case 'v':
+            verbose = 1;
+            break;
+        case 'V':
+            version(argv[0]);
+            exit(0);
+            break;
+        case 'h':
+            usage(argv[0]);
+            exit(0);
+            break;
+        case '?':
+            errx(EINVAL, "Try `%s --help' for more information.",
+                 argv[0]);
+        }
+    }
+
+    if ((argc - optind) != 1) {
+        errx(EINVAL, "Invalid number of argument.\n"
+             "Try `%s --help' for more information.",
+             argv[0]);
+    }
+
+    bdrv_init();
+
+    bs = bdrv_new("hda");
+    if (bs == NULL)
+        return 1;
+
+    if (bdrv_open(bs, argv[optind], snapshot) == -1)
+        return 1;
+
+    fd_size = bs->total_sectors * 512;
+
+    if (partition != -1 &&
+        find_partition(bs, partition, &dev_offset, &fd_size))
+        errx(errno, "Could not find partition %d", partition);
+
+    sock = tcp_socket_incoming(bindto, port);
+    if (sock == -1)
+        return 1;
+
+    csock = accept(sock,
+               (struct sockaddr *)&addr,
+               &addr_len);
+    if (csock == -1)
+        return 1;
+
+    /* new fd_size is calculated by find_partition */
+    if (nbd_negotiate(bs, csock, fd_size) == -1)
+        return 1;
+
+    while (nbd_trip(bs, csock, fd_size, dev_offset, &offset, readonly) == 0);
+
+    close(csock);
+    close(sock);
+    bdrv_close(bs);
+
+    return 0;
+}

qemu-nbd.texi

@@ -0,0 +1,52 @@
+@example
+@c man begin SYNOPSIS
+usage: qemu-nbd [OPTION]...  @var{filename}
+@c man end
+@end example
+
+@c man begin DESCRIPTION
+
+Export Qemu disk image using NBD protocol.
+
+@c man end
+
+@c man begin OPTIONS
+@table @var
+@item filename
+ is a disk image filename
+@item -p, --port=PORT
+  port to listen on (default `1024')
+@item -o, --offset=OFFSET
+  offset into the image
+@item -b, --bind=IFACE
+  interface to bind to (default `0.0.0.0')
+@item -r, --read-only
+  export read-only
+@item -P, --partition=NUM
+  only expose partition NUM
+@item -v, --verbose
+  display extra debugging information
+@item -h, --help
+  display this help and exit
+@item -V, --version
+  output version information and exit
+@end table
+
+@c man end
+
+@ignore
+
+@setfilename qemu-nbd
+@settitle QEMU Disk Network Block Device Server
+
+@c man begin AUTHOR
+Copyright (C) 2006 Anthony Liguori <anthony@codemonkey.ws>.
+This is free software; see the source for copying conditions.  There is NO
+warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+@c man end
+
+@c man begin SEEALSO
+qemu-img(1)
+@c man end
+
+@end ignore