| Message ID | 1282769313-25061-1-git-send-email-laurent@vivier.eu |
|---|---|
| State | New |
| Headers | show |
On 08/25/2010 03:48 PM, Laurent Vivier wrote: > This patch allows to connect Qemu using NBD protocol to an nbd-server > using named exports. > Does using a named export make the NBD protocol incompatible with a server that doesn't support named exports? IOW, it's essentially a new protocol layered underneath of NBD? Regards, Anthony Liguori > For instance, if on the host "isoserver", in /etc/nbd-server/config, you have: > > [generic] > [debian-500-ppc-netinst] > exportname = /ISO/debian-500-powerpc-netinst.iso > [Fedora-10-ppc-netinst] > exportname = /ISO/Fedora-10-ppc-netinst.iso > > You can connect to it, using: > > qemu -cdrom nbd:isoserver:exportname=debian-500-ppc-netinst > qemu -cdrom nbd:isoserver:exportname=Fedora-10-ppc-netinst > > NOTE: you need at least nbd-server 2.9.18 > > Signed-off-by: Laurent Vivier<laurent@vivier.eu> > --- > v3: change sizeof() by strlen() > v2: address Kevin comments (CODING STYLE) > > block/nbd.c | 68 +++++++++++++++++++++++--------- > nbd.c | 118 +++++++++++++++++++++++++++++++++++++++++++++++++++------ > nbd.h | 5 ++- > qemu-doc.texi | 7 +++ > qemu-nbd.c | 4 +- > 5 files changed, 169 insertions(+), 33 deletions(-) > > diff --git a/block/nbd.c b/block/nbd.c > index a1ec123..5e9d6cb 100644 > --- a/block/nbd.c > +++ b/block/nbd.c > @@ -33,6 +33,8 @@ > #include<sys/types.h> > #include<unistd.h> > > +#define EN_OPTSTR ":exportname=" > + > typedef struct BDRVNBDState { > int sock; > off_t size; > @@ -42,55 +44,83 @@ typedef struct BDRVNBDState { > static int nbd_open(BlockDriverState *bs, const char* filename, int flags) > { > BDRVNBDState *s = bs->opaque; > + uint32_t nbdflags; > + > + char *file; > + char *name; > const char *host; > const char *unixpath; > int sock; > off_t size; > size_t blocksize; > int ret; > + int err = -EINVAL; > + > + file = qemu_strdup(filename); > > - if (!strstart(filename, "nbd:",&host)) > - return -EINVAL; > + name = strstr(file, EN_OPTSTR); > + if (name) { > + if (name[strlen(EN_OPTSTR)] == 0) { > + goto out; > + } > + name[0] = 0; > + name += strlen(EN_OPTSTR); > + } > + > + if (!strstart(file, "nbd:",&host)) { > + goto out; > + } > > if (strstart(host, "unix:",&unixpath)) { > > - if (unixpath[0] != '/') > - return -EINVAL; > + if (unixpath[0] != '/') { > + goto out; > + } > > sock = unix_socket_outgoing(unixpath); > > } else { > - uint16_t port; > + uint16_t port = NBD_DEFAULT_PORT; > char *p, *r; > char hostname[128]; > > pstrcpy(hostname, 128, host); > > p = strchr(hostname, ':'); > - if (p == NULL) > - return -EINVAL; > + if (p != NULL) { > + *p = '\0'; > + p++; > + > + port = strtol(p,&r, 0); > + if (r == p) { > + goto out; > + } > + } else if (name == NULL) { > + goto out; > + } > > - *p = '\0'; > - p++; > - > - port = strtol(p,&r, 0); > - if (r == p) > - return -EINVAL; > sock = tcp_socket_outgoing(hostname, port); > } > > - if (sock == -1) > - return -errno; > + if (sock == -1) { > + err = -errno; > + goto out; > + } > > - ret = nbd_receive_negotiate(sock,&size,&blocksize); > - if (ret == -1) > - return -errno; > + ret = nbd_receive_negotiate(sock, name,&nbdflags,&size,&blocksize); > + if (ret == -1) { > + err = -errno; > + goto out; > + } > > s->sock = sock; > s->size = size; > s->blocksize = blocksize; > + err = 0; > > - return 0; > +out: > + qemu_free(file); > + return err; > } > > static int nbd_read(BlockDriverState *bs, int64_t sector_num, > diff --git a/nbd.c b/nbd.c > index a9f295f..30dec8d 100644 > --- a/nbd.c > +++ b/nbd.c > @@ -62,6 +62,8 @@ > #define NBD_SET_SIZE_BLOCKS _IO(0xab, 7) > #define NBD_DISCONNECT _IO(0xab, 8) > > +#define NBD_OPT_EXPORT_NAME (1<< 0) > + > /* That's all folks */ > > #define read_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, true) > @@ -296,22 +298,27 @@ int nbd_negotiate(int csock, off_t size) > return 0; > } > > -int nbd_receive_negotiate(int csock, off_t *size, size_t *blocksize) > +int nbd_receive_negotiate(int csock, const char *name, uint32_t *flags, > + off_t *size, size_t *blocksize) > { > - char buf[8 + 8 + 8 + 128]; > - uint64_t magic; > + char buf[256]; > + uint64_t magic, s; > + uint16_t tmp; > > TRACE("Receiving negotation."); > > - if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { > + if (read_sync(csock, buf, 8) != 8) { > LOG("read failed"); > errno = EINVAL; > return -1; > } > > - magic = be64_to_cpup((uint64_t*)(buf + 8)); > - *size = be64_to_cpup((uint64_t*)(buf + 16)); > - *blocksize = 1024; > + buf[8] = '\0'; > + if (strlen(buf) == 0) { > + LOG("server connection closed"); > + errno = EINVAL; > + return -1; > + } > > TRACE("Magic is %c%c%c%c%c%c%c%c", > qemu_isprint(buf[0]) ? buf[0] : '.', > @@ -322,8 +329,6 @@ int nbd_receive_negotiate(int csock, off_t *size, size_t *blocksize) > qemu_isprint(buf[5]) ? buf[5] : '.', > qemu_isprint(buf[6]) ? buf[6] : '.', > qemu_isprint(buf[7]) ? buf[7] : '.'); > - TRACE("Magic is 0x%" PRIx64, magic); > - TRACE("Size is %" PRIu64, *size); > > if (memcmp(buf, "NBDMAGIC", 8) != 0) { > LOG("Invalid magic received"); > @@ -331,10 +336,99 @@ int nbd_receive_negotiate(int csock, off_t *size, size_t *blocksize) > return -1; > } > > - TRACE("Checking magic"); > + if (read_sync(csock,&magic, sizeof(magic)) != sizeof(magic)) { > + LOG("read failed"); > + errno = EINVAL; > + return -1; > + } > + magic = be64_to_cpu(magic); > + TRACE("Magic is 0x%" PRIx64, magic); > + > + if (name) { > + uint32_t reserved = 0; > + uint32_t opt; > + uint32_t namesize; > + > + TRACE("Checking magic (opts_magic)"); > + if (magic != 0x49484156454F5054LL) { > + LOG("Bad magic received"); > + errno = EINVAL; > + return -1; > + } > + if (read_sync(csock,&tmp, sizeof(tmp)) != sizeof(tmp)) { > + LOG("flags read failed"); > + errno = EINVAL; > + return -1; > + } > + *flags = be16_to_cpu(tmp)<< 16; > + /* reserved for future use */ > + if (write_sync(csock,&reserved, sizeof(reserved)) != > + sizeof(reserved)) { > + LOG("write failed (reserved)"); > + errno = EINVAL; > + return -1; > + } > + /* write the export name */ > + magic = cpu_to_be64(magic); > + if (write_sync(csock,&magic, sizeof(magic)) != sizeof(magic)) { > + LOG("write failed (magic)"); > + errno = EINVAL; > + return -1; > + } > + opt = cpu_to_be32(NBD_OPT_EXPORT_NAME); > + if (write_sync(csock,&opt, sizeof(opt)) != sizeof(opt)) { > + LOG("write failed (opt)"); > + errno = EINVAL; > + return -1; > + } > + namesize = cpu_to_be32(strlen(name)); > + if (write_sync(csock,&namesize, sizeof(namesize)) != > + sizeof(namesize)) { > + LOG("write failed (namesize)"); > + errno = EINVAL; > + return -1; > + } > + if (write_sync(csock, (char*)name, strlen(name)) != strlen(name)) { > + LOG("write failed (name)"); > + errno = EINVAL; > + return -1; > + } > + } else { > + TRACE("Checking magic (cli_magic)"); > + > + if (magic != 0x00420281861253LL) { > + LOG("Bad magic received"); > + errno = EINVAL; > + return -1; > + } > + } > + > + if (read_sync(csock,&s, sizeof(s)) != sizeof(s)) { > + LOG("read failed"); > + errno = EINVAL; > + return -1; > + } > + *size = be64_to_cpu(s); > + *blocksize = 1024; > + TRACE("Size is %" PRIu64, *size); > > - if (magic != 0x00420281861253LL) { > - LOG("Bad magic received"); > + if (!name) { > + if (read_sync(csock, flags, sizeof(*flags)) != sizeof(*flags)) { > + LOG("read failed (flags)"); > + errno = EINVAL; > + return -1; > + } > + *flags = be32_to_cpup(flags); > + } else { > + if (read_sync(csock,&tmp, sizeof(tmp)) != sizeof(tmp)) { > + LOG("read failed (tmp)"); > + errno = EINVAL; > + return -1; > + } > + *flags |= be32_to_cpu(tmp); > + } > + if (read_sync(csock,&buf, 124) != 124) { > + LOG("read failed (buf)"); > errno = EINVAL; > return -1; > } > diff --git a/nbd.h b/nbd.h > index 5a1fbdf..8ff65a1 100644 > --- a/nbd.h > +++ b/nbd.h > @@ -42,6 +42,8 @@ enum { > NBD_CMD_DISC = 2 > }; > > +#define NBD_DEFAULT_PORT 10809 > + > size_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read); > int tcp_socket_outgoing(const char *address, uint16_t port); > int tcp_socket_incoming(const char *address, uint16_t port); > @@ -49,7 +51,8 @@ int unix_socket_outgoing(const char *path); > int unix_socket_incoming(const char *path); > > int nbd_negotiate(int csock, off_t size); > -int nbd_receive_negotiate(int csock, off_t *size, size_t *blocksize); > +int nbd_receive_negotiate(int csock, const char *name, uint32_t *flags, > + off_t *size, size_t *blocksize); > int nbd_init(int fd, int csock, off_t size, size_t blocksize); > int nbd_send_request(int csock, struct nbd_request *request); > int nbd_receive_reply(int csock, struct nbd_reply *reply); > diff --git a/qemu-doc.texi b/qemu-doc.texi > index 55a966f..d7d760f 100644 > --- a/qemu-doc.texi > +++ b/qemu-doc.texi > @@ -620,6 +620,13 @@ qemu linux1.img -hdb nbd:unix:/tmp/my_socket > qemu linux2.img -hdb nbd:unix:/tmp/my_socket > @end example > > +If the nbd-server uses named exports (since NBD 2.9.18), you must use the > +"exportname" option: > +@example > +qemu -cdrom nbd:localhost:exportname=debian-500-ppc-netinst > +qemu -cdrom nbd:localhost:exportname=openSUSE-11.1-ppc-netinst > +@end example > + > @node pcsys_network > @section Network emulation > > diff --git a/qemu-nbd.c b/qemu-nbd.c > index 4e607cf..41e5c5d 100644 > --- a/qemu-nbd.c > +++ b/qemu-nbd.c > @@ -230,6 +230,7 @@ int main(int argc, char **argv) > int nb_fds = 0; > int max_fd; > int persistent = 0; > + uint32_t nbdflags; > > while ((ch = getopt_long(argc, argv, sopt, lopt,&opt_ind)) != -1) { > switch (ch) { > @@ -398,7 +399,8 @@ int main(int argc, char **argv) > goto out; > } > > - ret = nbd_receive_negotiate(sock,&size,&blocksize); > + ret = nbd_receive_negotiate(sock, NULL,&nbdflags, > + &size,&blocksize); > if (ret == -1) { > ret = 1; > goto out; >
Am 25.08.2010 22:48, schrieb Laurent Vivier: > This patch allows to connect Qemu using NBD protocol to an nbd-server > using named exports. > > For instance, if on the host "isoserver", in /etc/nbd-server/config, you have: > > [generic] > [debian-500-ppc-netinst] > exportname = /ISO/debian-500-powerpc-netinst.iso > [Fedora-10-ppc-netinst] > exportname = /ISO/Fedora-10-ppc-netinst.iso > > You can connect to it, using: > > qemu -cdrom nbd:isoserver:exportname=debian-500-ppc-netinst > qemu -cdrom nbd:isoserver:exportname=Fedora-10-ppc-netinst > > NOTE: you need at least nbd-server 2.9.18 > > Signed-off-by: Laurent Vivier <laurent@vivier.eu> Thanks, applied to the block branch. Kevin
diff --git a/block/nbd.c b/block/nbd.c index a1ec123..5e9d6cb 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -33,6 +33,8 @@ #include <sys/types.h> #include <unistd.h> +#define EN_OPTSTR ":exportname=" + typedef struct BDRVNBDState { int sock; off_t size; @@ -42,55 +44,83 @@ typedef struct BDRVNBDState { static int nbd_open(BlockDriverState *bs, const char* filename, int flags) { BDRVNBDState *s = bs->opaque; + uint32_t nbdflags; + + char *file; + char *name; const char *host; const char *unixpath; int sock; off_t size; size_t blocksize; int ret; + int err = -EINVAL; + + file = qemu_strdup(filename); - if (!strstart(filename, "nbd:", &host)) - return -EINVAL; + name = strstr(file, EN_OPTSTR); + if (name) { + if (name[strlen(EN_OPTSTR)] == 0) { + goto out; + } + name[0] = 0; + name += strlen(EN_OPTSTR); + } + + if (!strstart(file, "nbd:", &host)) { + goto out; + } if (strstart(host, "unix:", &unixpath)) { - if (unixpath[0] != '/') - return -EINVAL; + if (unixpath[0] != '/') { + goto out; + } sock = unix_socket_outgoing(unixpath); } else { - uint16_t port; + uint16_t port = NBD_DEFAULT_PORT; char *p, *r; char hostname[128]; pstrcpy(hostname, 128, host); p = strchr(hostname, ':'); - if (p == NULL) - return -EINVAL; + if (p != NULL) { + *p = '\0'; + p++; + + port = strtol(p, &r, 0); + if (r == p) { + goto out; + } + } else if (name == NULL) { + goto out; + } - *p = '\0'; - p++; - - port = strtol(p, &r, 0); - if (r == p) - return -EINVAL; sock = tcp_socket_outgoing(hostname, port); } - if (sock == -1) - return -errno; + if (sock == -1) { + err = -errno; + goto out; + } - ret = nbd_receive_negotiate(sock, &size, &blocksize); - if (ret == -1) - return -errno; + ret = nbd_receive_negotiate(sock, name, &nbdflags, &size, &blocksize); + if (ret == -1) { + err = -errno; + goto out; + } s->sock = sock; s->size = size; s->blocksize = blocksize; + err = 0; - return 0; +out: + qemu_free(file); + return err; } static int nbd_read(BlockDriverState *bs, int64_t sector_num, diff --git a/nbd.c b/nbd.c index a9f295f..30dec8d 100644 --- a/nbd.c +++ b/nbd.c @@ -62,6 +62,8 @@ #define NBD_SET_SIZE_BLOCKS _IO(0xab, 7) #define NBD_DISCONNECT _IO(0xab, 8) +#define NBD_OPT_EXPORT_NAME (1 << 0) + /* That's all folks */ #define read_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, true) @@ -296,22 +298,27 @@ int nbd_negotiate(int csock, off_t size) return 0; } -int nbd_receive_negotiate(int csock, off_t *size, size_t *blocksize) +int nbd_receive_negotiate(int csock, const char *name, uint32_t *flags, + off_t *size, size_t *blocksize) { - char buf[8 + 8 + 8 + 128]; - uint64_t magic; + char buf[256]; + uint64_t magic, s; + uint16_t tmp; TRACE("Receiving negotation."); - if (read_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { + if (read_sync(csock, buf, 8) != 8) { LOG("read failed"); errno = EINVAL; return -1; } - magic = be64_to_cpup((uint64_t*)(buf + 8)); - *size = be64_to_cpup((uint64_t*)(buf + 16)); - *blocksize = 1024; + buf[8] = '\0'; + if (strlen(buf) == 0) { + LOG("server connection closed"); + errno = EINVAL; + return -1; + } TRACE("Magic is %c%c%c%c%c%c%c%c", qemu_isprint(buf[0]) ? buf[0] : '.', @@ -322,8 +329,6 @@ int nbd_receive_negotiate(int csock, off_t *size, size_t *blocksize) qemu_isprint(buf[5]) ? buf[5] : '.', qemu_isprint(buf[6]) ? buf[6] : '.', qemu_isprint(buf[7]) ? buf[7] : '.'); - TRACE("Magic is 0x%" PRIx64, magic); - TRACE("Size is %" PRIu64, *size); if (memcmp(buf, "NBDMAGIC", 8) != 0) { LOG("Invalid magic received"); @@ -331,10 +336,99 @@ int nbd_receive_negotiate(int csock, off_t *size, size_t *blocksize) return -1; } - TRACE("Checking magic"); + if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { + LOG("read failed"); + errno = EINVAL; + return -1; + } + magic = be64_to_cpu(magic); + TRACE("Magic is 0x%" PRIx64, magic); + + if (name) { + uint32_t reserved = 0; + uint32_t opt; + uint32_t namesize; + + TRACE("Checking magic (opts_magic)"); + if (magic != 0x49484156454F5054LL) { + LOG("Bad magic received"); + errno = EINVAL; + return -1; + } + if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { + LOG("flags read failed"); + errno = EINVAL; + return -1; + } + *flags = be16_to_cpu(tmp) << 16; + /* reserved for future use */ + if (write_sync(csock, &reserved, sizeof(reserved)) != + sizeof(reserved)) { + LOG("write failed (reserved)"); + errno = EINVAL; + return -1; + } + /* write the export name */ + magic = cpu_to_be64(magic); + if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { + LOG("write failed (magic)"); + errno = EINVAL; + return -1; + } + opt = cpu_to_be32(NBD_OPT_EXPORT_NAME); + if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) { + LOG("write failed (opt)"); + errno = EINVAL; + return -1; + } + namesize = cpu_to_be32(strlen(name)); + if (write_sync(csock, &namesize, sizeof(namesize)) != + sizeof(namesize)) { + LOG("write failed (namesize)"); + errno = EINVAL; + return -1; + } + if (write_sync(csock, (char*)name, strlen(name)) != strlen(name)) { + LOG("write failed (name)"); + errno = EINVAL; + return -1; + } + } else { + TRACE("Checking magic (cli_magic)"); + + if (magic != 0x00420281861253LL) { + LOG("Bad magic received"); + errno = EINVAL; + return -1; + } + } + + if (read_sync(csock, &s, sizeof(s)) != sizeof(s)) { + LOG("read failed"); + errno = EINVAL; + return -1; + } + *size = be64_to_cpu(s); + *blocksize = 1024; + TRACE("Size is %" PRIu64, *size); - if (magic != 0x00420281861253LL) { - LOG("Bad magic received"); + if (!name) { + if (read_sync(csock, flags, sizeof(*flags)) != sizeof(*flags)) { + LOG("read failed (flags)"); + errno = EINVAL; + return -1; + } + *flags = be32_to_cpup(flags); + } else { + if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { + LOG("read failed (tmp)"); + errno = EINVAL; + return -1; + } + *flags |= be32_to_cpu(tmp); + } + if (read_sync(csock, &buf, 124) != 124) { + LOG("read failed (buf)"); errno = EINVAL; return -1; } diff --git a/nbd.h b/nbd.h index 5a1fbdf..8ff65a1 100644 --- a/nbd.h +++ b/nbd.h @@ -42,6 +42,8 @@ enum { NBD_CMD_DISC = 2 }; +#define NBD_DEFAULT_PORT 10809 + size_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read); int tcp_socket_outgoing(const char *address, uint16_t port); int tcp_socket_incoming(const char *address, uint16_t port); @@ -49,7 +51,8 @@ int unix_socket_outgoing(const char *path); int unix_socket_incoming(const char *path); int nbd_negotiate(int csock, off_t size); -int nbd_receive_negotiate(int csock, off_t *size, size_t *blocksize); +int nbd_receive_negotiate(int csock, const char *name, uint32_t *flags, + off_t *size, size_t *blocksize); int nbd_init(int fd, int csock, off_t size, size_t blocksize); int nbd_send_request(int csock, struct nbd_request *request); int nbd_receive_reply(int csock, struct nbd_reply *reply); diff --git a/qemu-doc.texi b/qemu-doc.texi index 55a966f..d7d760f 100644 --- a/qemu-doc.texi +++ b/qemu-doc.texi @@ -620,6 +620,13 @@ qemu linux1.img -hdb nbd:unix:/tmp/my_socket qemu linux2.img -hdb nbd:unix:/tmp/my_socket @end example +If the nbd-server uses named exports (since NBD 2.9.18), you must use the +"exportname" option: +@example +qemu -cdrom nbd:localhost:exportname=debian-500-ppc-netinst +qemu -cdrom nbd:localhost:exportname=openSUSE-11.1-ppc-netinst +@end example + @node pcsys_network @section Network emulation diff --git a/qemu-nbd.c b/qemu-nbd.c index 4e607cf..41e5c5d 100644 --- a/qemu-nbd.c +++ b/qemu-nbd.c @@ -230,6 +230,7 @@ int main(int argc, char **argv) int nb_fds = 0; int max_fd; int persistent = 0; + uint32_t nbdflags; while ((ch = getopt_long(argc, argv, sopt, lopt, &opt_ind)) != -1) { switch (ch) { @@ -398,7 +399,8 @@ int main(int argc, char **argv) goto out; } - ret = nbd_receive_negotiate(sock, &size, &blocksize); + ret = nbd_receive_negotiate(sock, NULL, &nbdflags, + &size, &blocksize); if (ret == -1) { ret = 1; goto out;
This patch allows to connect Qemu using NBD protocol to an nbd-server using named exports. For instance, if on the host "isoserver", in /etc/nbd-server/config, you have: [generic] [debian-500-ppc-netinst] exportname = /ISO/debian-500-powerpc-netinst.iso [Fedora-10-ppc-netinst] exportname = /ISO/Fedora-10-ppc-netinst.iso You can connect to it, using: qemu -cdrom nbd:isoserver:exportname=debian-500-ppc-netinst qemu -cdrom nbd:isoserver:exportname=Fedora-10-ppc-netinst NOTE: you need at least nbd-server 2.9.18 Signed-off-by: Laurent Vivier <laurent@vivier.eu> --- v3: change sizeof() by strlen() v2: address Kevin comments (CODING STYLE) block/nbd.c | 68 +++++++++++++++++++++++--------- nbd.c | 118 +++++++++++++++++++++++++++++++++++++++++++++++++++------ nbd.h | 5 ++- qemu-doc.texi | 7 +++ qemu-nbd.c | 4 +- 5 files changed, 169 insertions(+), 33 deletions(-)