Commit 798bfe00 authored by Fam Zheng's avatar Fam Zheng Committed by Paolo Bonzini
Browse files

nbd: Split nbd.c 



We have NBD server code and client code, all mixed in a file. Now split
them into separate files under nbd/, and update MAINTAINERS.

filter_nbd for iotest 083 is updated to keep the log filtered out.

Signed-off-by: default avatarFam Zheng <famz@redhat.com>
Message-Id: <1452760863-25350-3-git-send-email-famz@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent ee7d7aab

MAINTAINERS

+3 −2
Original line number Diff line number Diff line
@@ -1116,8 +1116,9 @@ F: net/netmap.c 
Network Block Device (NBD)

M: Paolo Bonzini <pbonzini@redhat.com>

S: Odd Fixes

F: block/nbd.c

F: nbd.*

F: block/nbd*

F: nbd/

F: include/block/nbd*

F: qemu-nbd.c

T: git git://github.com/bonzini/qemu.git nbd-next

Makefile.objs

+2 −1
Original line number Diff line number Diff line
@@ -8,7 +8,8 @@ util-obj-y += qmp-introspect.o qapi-types.o qapi-visit.o qapi-event.o 
# block-obj-y is code used by both qemu system emulation and qemu-img



block-obj-y = async.o thread-pool.o

block-obj-y += nbd.o block.o blockjob.o

block-obj-y += nbd/

block-obj-y += block.o blockjob.o

block-obj-y += main-loop.o iohandler.o qemu-timer.o

block-obj-$(CONFIG_POSIX) += aio-posix.o

block-obj-$(CONFIG_WIN32) += aio-win32.o

nbd/Makefile.objs

0 → 100644
+1 −0
Original line number Diff line number Diff line 
block-obj-y += server.o client.o common.o

nbd/client.c

0 → 100644
+361 −0
Original line number Diff line number Diff line 
/*

 *  Copyright (C) 2005  Anthony Liguori <anthony@codemonkey.ws>

 *

 *  Network Block Device Client Side

 *

 *  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, see <http://www.gnu.org/licenses/>.

 */



#include "nbd-internal.h"



static int nbd_errno_to_system_errno(int err)

{

    switch (err) {

    case NBD_SUCCESS:

        return 0;

    case NBD_EPERM:

        return EPERM;

    case NBD_EIO:

        return EIO;

    case NBD_ENOMEM:

        return ENOMEM;

    case NBD_ENOSPC:

        return ENOSPC;

    case NBD_EINVAL:

    default:

        return EINVAL;

    }

}



/* Definitions for opaque data types */



static QTAILQ_HEAD(, NBDExport) exports = QTAILQ_HEAD_INITIALIZER(exports);



/* That's all folks */



/* Basic flow for negotiation



   Server         Client

   Negotiate



   or



   Server         Client

   Negotiate #1

                  Option

   Negotiate #2



   ----



   followed by



   Server         Client

                  Request

   Response

                  Request

   Response

                  ...

   ...

                  Request (type == 2)



*/



int nbd_receive_negotiate(int csock, const char *name, uint32_t *flags,

                          off_t *size, Error **errp)

{

    char buf[256];

    uint64_t magic, s;

    uint16_t tmp;

    int rc;



    TRACE("Receiving negotiation.");



    rc = -EINVAL;



    if (read_sync(csock, buf, 8) != 8) {

        error_setg(errp, "Failed to read data");

        goto fail;

    }



    buf[8] = '\0';

    if (strlen(buf) == 0) {

        error_setg(errp, "Server connection closed unexpectedly");

        goto fail;

    }



    TRACE("Magic is %c%c%c%c%c%c%c%c",

          qemu_isprint(buf[0]) ? buf[0] : '.',

          qemu_isprint(buf[1]) ? buf[1] : '.',

          qemu_isprint(buf[2]) ? buf[2] : '.',

          qemu_isprint(buf[3]) ? buf[3] : '.',

          qemu_isprint(buf[4]) ? buf[4] : '.',

          qemu_isprint(buf[5]) ? buf[5] : '.',

          qemu_isprint(buf[6]) ? buf[6] : '.',

          qemu_isprint(buf[7]) ? buf[7] : '.');



    if (memcmp(buf, "NBDMAGIC", 8) != 0) {

        error_setg(errp, "Invalid magic received");

        goto fail;

    }



    if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {

        error_setg(errp, "Failed to read magic");

        goto fail;

    }

    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 != NBD_OPTS_MAGIC) {

            if (magic == NBD_CLIENT_MAGIC) {

                error_setg(errp, "Server does not support export names");

            } else {

                error_setg(errp, "Bad magic received");

            }

            goto fail;

        }

        if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {

            error_setg(errp, "Failed to read server flags");

            goto fail;

        }

        *flags = be16_to_cpu(tmp) << 16;

        /* reserved for future use */

        if (write_sync(csock, &reserved, sizeof(reserved)) !=

            sizeof(reserved)) {

            error_setg(errp, "Failed to read reserved field");

            goto fail;

        }

        /* write the export name */

        magic = cpu_to_be64(magic);

        if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) {

            error_setg(errp, "Failed to send export name magic");

            goto fail;

        }

        opt = cpu_to_be32(NBD_OPT_EXPORT_NAME);

        if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) {

            error_setg(errp, "Failed to send export name option number");

            goto fail;

        }

        namesize = cpu_to_be32(strlen(name));

        if (write_sync(csock, &namesize, sizeof(namesize)) !=

            sizeof(namesize)) {

            error_setg(errp, "Failed to send export name length");

            goto fail;

        }

        if (write_sync(csock, (char*)name, strlen(name)) != strlen(name)) {

            error_setg(errp, "Failed to send export name");

            goto fail;

        }

    } else {

        TRACE("Checking magic (cli_magic)");



        if (magic != NBD_CLIENT_MAGIC) {

            if (magic == NBD_OPTS_MAGIC) {

                error_setg(errp, "Server requires an export name");

            } else {

                error_setg(errp, "Bad magic received");

            }

            goto fail;

        }

    }



    if (read_sync(csock, &s, sizeof(s)) != sizeof(s)) {

        error_setg(errp, "Failed to read export length");

        goto fail;

    }

    *size = be64_to_cpu(s);

    TRACE("Size is %" PRIu64, *size);



    if (!name) {

        if (read_sync(csock, flags, sizeof(*flags)) != sizeof(*flags)) {

            error_setg(errp, "Failed to read export flags");

            goto fail;

        }

        *flags = be32_to_cpup(flags);

    } else {

        if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) {

            error_setg(errp, "Failed to read export flags");

            goto fail;

        }

        *flags |= be16_to_cpu(tmp);

    }

    if (read_sync(csock, &buf, 124) != 124) {

        error_setg(errp, "Failed to read reserved block");

        goto fail;

    }

    rc = 0;



fail:

    return rc;

}



#ifdef __linux__

int nbd_init(int fd, int csock, uint32_t flags, off_t size)

{

    TRACE("Setting NBD socket");



    if (ioctl(fd, NBD_SET_SOCK, csock) < 0) {

        int serrno = errno;

        LOG("Failed to set NBD socket");

        return -serrno;

    }



    TRACE("Setting block size to %lu", (unsigned long)BDRV_SECTOR_SIZE);



    if (ioctl(fd, NBD_SET_BLKSIZE, (size_t)BDRV_SECTOR_SIZE) < 0) {

        int serrno = errno;

        LOG("Failed setting NBD block size");

        return -serrno;

    }



    TRACE("Setting size to %zd block(s)", (size_t)(size / BDRV_SECTOR_SIZE));



    if (ioctl(fd, NBD_SET_SIZE_BLOCKS, (size_t)(size / BDRV_SECTOR_SIZE)) < 0) {

        int serrno = errno;

        LOG("Failed setting size (in blocks)");

        return -serrno;

    }



    if (ioctl(fd, NBD_SET_FLAGS, flags) < 0) {

        if (errno == ENOTTY) {

            int read_only = (flags & NBD_FLAG_READ_ONLY) != 0;

            TRACE("Setting readonly attribute");



            if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) {

                int serrno = errno;

                LOG("Failed setting read-only attribute");

                return -serrno;

            }

        } else {

            int serrno = errno;

            LOG("Failed setting flags");

            return -serrno;

        }

    }



    TRACE("Negotiation ended");



    return 0;

}



int nbd_client(int fd)

{

    int ret;

    int serrno;



    TRACE("Doing NBD loop");



    ret = ioctl(fd, NBD_DO_IT);

    if (ret < 0 && errno == EPIPE) {

        /* NBD_DO_IT normally returns EPIPE when someone has disconnected

         * the socket via NBD_DISCONNECT.  We do not want to return 1 in

         * that case.

         */

        ret = 0;

    }

    serrno = errno;



    TRACE("NBD loop returned %d: %s", ret, strerror(serrno));



    TRACE("Clearing NBD queue");

    ioctl(fd, NBD_CLEAR_QUE);



    TRACE("Clearing NBD socket");

    ioctl(fd, NBD_CLEAR_SOCK);



    errno = serrno;

    return ret;

}

#else

int nbd_init(int fd, int csock, uint32_t flags, off_t size)

{

    return -ENOTSUP;

}



int nbd_client(int fd)

{

    return -ENOTSUP;

}

#endif



ssize_t nbd_send_request(int csock, struct nbd_request *request)

{

    uint8_t buf[NBD_REQUEST_SIZE];

    ssize_t ret;



    cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC);

    cpu_to_be32w((uint32_t*)(buf + 4), request->type);

    cpu_to_be64w((uint64_t*)(buf + 8), request->handle);

    cpu_to_be64w((uint64_t*)(buf + 16), request->from);

    cpu_to_be32w((uint32_t*)(buf + 24), request->len);



    TRACE("Sending request to client: "

          "{ .from = %" PRIu64", .len = %u, .handle = %" PRIu64", .type=%i}",

          request->from, request->len, request->handle, request->type);



    ret = write_sync(csock, buf, sizeof(buf));

    if (ret < 0) {

        return ret;

    }



    if (ret != sizeof(buf)) {

        LOG("writing to socket failed");

        return -EINVAL;

    }

    return 0;

}



ssize_t nbd_receive_reply(int csock, struct nbd_reply *reply)

{

    uint8_t buf[NBD_REPLY_SIZE];

    uint32_t magic;

    ssize_t ret;



    ret = read_sync(csock, buf, sizeof(buf));

    if (ret < 0) {

        return ret;

    }



    if (ret != sizeof(buf)) {

        LOG("read failed");

        return -EINVAL;

    }



    /* Reply

       [ 0 ..  3]    magic   (NBD_REPLY_MAGIC)

       [ 4 ..  7]    error   (0 == no error)

       [ 7 .. 15]    handle

     */



    magic = be32_to_cpup((uint32_t*)buf);

    reply->error  = be32_to_cpup((uint32_t*)(buf + 4));

    reply->handle = be64_to_cpup((uint64_t*)(buf + 8));



    reply->error = nbd_errno_to_system_errno(reply->error);



    TRACE("Got reply: "

          "{ magic = 0x%x, .error = %d, handle = %" PRIu64" }",

          magic, reply->error, reply->handle);



    if (magic != NBD_REPLY_MAGIC) {

        LOG("invalid magic (got 0x%x)", magic);

        return -EINVAL;

    }

    return 0;

}

nbd/common.c

0 → 100644
+64 −0
Original line number Diff line number Diff line 
/*

 *  Copyright (C) 2005  Anthony Liguori <anthony@codemonkey.ws>

 *

 *  Network Block Device Common Code

 *

 *  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, see <http://www.gnu.org/licenses/>.

 */



#include "nbd-internal.h"



ssize_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read)

{

    size_t offset = 0;

    int err;



    if (qemu_in_coroutine()) {

        if (do_read) {

            return qemu_co_recv(fd, buffer, size);

        } else {

            return qemu_co_send(fd, buffer, size);

        }

    }



    while (offset < size) {

        ssize_t len;



        if (do_read) {

            len = qemu_recv(fd, buffer + offset, size - offset, 0);

        } else {

            len = send(fd, buffer + offset, size - offset, 0);

        }



        if (len < 0) {

            err = socket_error();



            /* recoverable error */

            if (err == EINTR || (offset > 0 && (err == EAGAIN || err == EWOULDBLOCK))) {

                continue;

            }



            /* unrecoverable error */

            return -err;

        }



        /* eof */

        if (len == 0) {

            break;

        }



        offset += len;

    }



    return offset;

}