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/*
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* Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
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*
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* Network Block Device
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; under version 2 of the License.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, see <http://www.gnu.org/licenses/>.
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*/
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#include "nbd.h" |
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#include "block.h" |
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#include "block_int.h" |
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#include "qemu-coroutine.h" |
24 |
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#include <errno.h> |
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#include <string.h> |
27 |
#ifndef _WIN32
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#include <sys/ioctl.h> |
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#endif
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#if defined(__sun__) || defined(__HAIKU__)
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#include <sys/ioccom.h> |
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#endif
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#include <ctype.h> |
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#include <inttypes.h> |
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#ifdef __linux__
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#include <linux/fs.h> |
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#endif
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#include "qemu_socket.h" |
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#include "qemu-queue.h" |
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//#define DEBUG_NBD
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#ifdef DEBUG_NBD
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#define TRACE(msg, ...) do { \ |
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LOG(msg, ## __VA_ARGS__); \ |
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} while(0) |
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#else
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#define TRACE(msg, ...) \
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do { } while (0) |
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#endif
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|
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#define LOG(msg, ...) do { \ |
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fprintf(stderr, "%s:%s():L%d: " msg "\n", \ |
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__FILE__, __FUNCTION__, __LINE__, ## __VA_ARGS__); \ |
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} while(0) |
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/* This is all part of the "official" NBD API */
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|
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#define NBD_REPLY_SIZE (4 + 4 + 8) |
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#define NBD_REQUEST_MAGIC 0x25609513 |
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#define NBD_REPLY_MAGIC 0x67446698 |
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|
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#define NBD_SET_SOCK _IO(0xab, 0) |
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#define NBD_SET_BLKSIZE _IO(0xab, 1) |
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#define NBD_SET_SIZE _IO(0xab, 2) |
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#define NBD_DO_IT _IO(0xab, 3) |
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#define NBD_CLEAR_SOCK _IO(0xab, 4) |
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#define NBD_CLEAR_QUE _IO(0xab, 5) |
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#define NBD_PRINT_DEBUG _IO(0xab, 6) |
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#define NBD_SET_SIZE_BLOCKS _IO(0xab, 7) |
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#define NBD_DISCONNECT _IO(0xab, 8) |
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#define NBD_SET_TIMEOUT _IO(0xab, 9) |
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#define NBD_SET_FLAGS _IO(0xab, 10) |
76 |
|
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#define NBD_OPT_EXPORT_NAME (1 << 0) |
78 |
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/* That's all folks */
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#define read_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, true) |
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#define write_sync(fd, buffer, size) nbd_wr_sync(fd, buffer, size, false) |
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ssize_t nbd_wr_sync(int fd, void *buffer, size_t size, bool do_read) |
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{ |
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size_t offset = 0;
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int err;
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if (qemu_in_coroutine()) {
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if (do_read) {
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return qemu_co_recv(fd, buffer, size);
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} else {
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return qemu_co_send(fd, buffer, size);
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} |
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} |
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while (offset < size) {
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ssize_t len; |
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if (do_read) {
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len = qemu_recv(fd, buffer + offset, size - offset, 0);
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} else {
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len = send(fd, buffer + offset, size - offset, 0);
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} |
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if (len < 0) { |
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err = socket_error(); |
108 |
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/* recoverable error */
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if (err == EINTR || err == EAGAIN) {
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continue;
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} |
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/* unrecoverable error */
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return -err;
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} |
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/* eof */
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if (len == 0) { |
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break;
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} |
122 |
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offset += len; |
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} |
125 |
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return offset;
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} |
128 |
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static void combine_addr(char *buf, size_t len, const char* address, |
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uint16_t port) |
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{ |
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/* If the address-part contains a colon, it's an IPv6 IP so needs [] */
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if (strstr(address, ":")) { |
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snprintf(buf, len, "[%s]:%u", address, port);
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} else {
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snprintf(buf, len, "%s:%u", address, port);
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} |
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} |
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int tcp_socket_outgoing(const char *address, uint16_t port) |
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{ |
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char address_and_port[128]; |
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combine_addr(address_and_port, 128, address, port);
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return tcp_socket_outgoing_spec(address_and_port);
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} |
146 |
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int tcp_socket_outgoing_spec(const char *address_and_port) |
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{ |
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return inet_connect(address_and_port, SOCK_STREAM);
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} |
151 |
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int tcp_socket_incoming(const char *address, uint16_t port) |
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{ |
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char address_and_port[128]; |
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combine_addr(address_and_port, 128, address, port);
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return tcp_socket_incoming_spec(address_and_port);
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} |
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int tcp_socket_incoming_spec(const char *address_and_port) |
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{ |
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char *ostr = NULL; |
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int olen = 0; |
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return inet_listen(address_and_port, ostr, olen, SOCK_STREAM, 0); |
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} |
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int unix_socket_incoming(const char *path) |
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{ |
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char *ostr = NULL; |
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int olen = 0; |
170 |
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return unix_listen(path, ostr, olen);
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} |
173 |
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int unix_socket_outgoing(const char *path) |
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{ |
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return unix_connect(path);
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} |
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/* Basic flow
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Server Client
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Negotiate
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Request
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Response
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Request
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Response
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...
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...
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Request (type == 2)
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*/
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static int nbd_send_negotiate(int csock, off_t size, uint32_t flags) |
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{ |
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char buf[8 + 8 + 8 + 128]; |
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int rc;
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/* Negotiate
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[ 0 .. 7] passwd ("NBDMAGIC")
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[ 8 .. 15] magic (0x00420281861253)
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[16 .. 23] size
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[24 .. 27] flags
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[28 .. 151] reserved (0)
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*/
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rc = -EINVAL; |
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TRACE("Beginning negotiation.");
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memcpy(buf, "NBDMAGIC", 8); |
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cpu_to_be64w((uint64_t*)(buf + 8), 0x00420281861253LL); |
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cpu_to_be64w((uint64_t*)(buf + 16), size);
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cpu_to_be32w((uint32_t*)(buf + 24),
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flags | NBD_FLAG_HAS_FLAGS | NBD_FLAG_SEND_TRIM | |
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NBD_FLAG_SEND_FLUSH | NBD_FLAG_SEND_FUA); |
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memset(buf + 28, 0, 124); |
216 |
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if (write_sync(csock, buf, sizeof(buf)) != sizeof(buf)) { |
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LOG("write failed");
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goto fail;
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} |
221 |
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TRACE("Negotiation succeeded.");
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rc = 0;
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fail:
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return rc;
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} |
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int nbd_receive_negotiate(int csock, const char *name, uint32_t *flags, |
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off_t *size, size_t *blocksize) |
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{ |
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char buf[256]; |
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uint64_t magic, s; |
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uint16_t tmp; |
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int rc;
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TRACE("Receiving negotiation.");
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rc = -EINVAL; |
239 |
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if (read_sync(csock, buf, 8) != 8) { |
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LOG("read failed");
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goto fail;
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} |
244 |
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buf[8] = '\0'; |
246 |
if (strlen(buf) == 0) { |
247 |
LOG("server connection closed");
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goto fail;
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} |
250 |
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TRACE("Magic is %c%c%c%c%c%c%c%c",
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qemu_isprint(buf[0]) ? buf[0] : '.', |
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qemu_isprint(buf[1]) ? buf[1] : '.', |
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qemu_isprint(buf[2]) ? buf[2] : '.', |
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qemu_isprint(buf[3]) ? buf[3] : '.', |
256 |
qemu_isprint(buf[4]) ? buf[4] : '.', |
257 |
qemu_isprint(buf[5]) ? buf[5] : '.', |
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qemu_isprint(buf[6]) ? buf[6] : '.', |
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qemu_isprint(buf[7]) ? buf[7] : '.'); |
260 |
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if (memcmp(buf, "NBDMAGIC", 8) != 0) { |
262 |
LOG("Invalid magic received");
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goto fail;
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} |
265 |
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if (read_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { |
267 |
LOG("read failed");
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goto fail;
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} |
270 |
magic = be64_to_cpu(magic); |
271 |
TRACE("Magic is 0x%" PRIx64, magic);
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if (name) {
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uint32_t reserved = 0;
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uint32_t opt; |
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uint32_t namesize; |
277 |
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TRACE("Checking magic (opts_magic)");
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if (magic != 0x49484156454F5054LL) { |
280 |
LOG("Bad magic received");
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goto fail;
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} |
283 |
if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { |
284 |
LOG("flags read failed");
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goto fail;
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286 |
} |
287 |
*flags = be16_to_cpu(tmp) << 16;
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/* reserved for future use */
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if (write_sync(csock, &reserved, sizeof(reserved)) != |
290 |
sizeof(reserved)) {
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LOG("write failed (reserved)");
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goto fail;
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293 |
} |
294 |
/* write the export name */
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295 |
magic = cpu_to_be64(magic); |
296 |
if (write_sync(csock, &magic, sizeof(magic)) != sizeof(magic)) { |
297 |
LOG("write failed (magic)");
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298 |
goto fail;
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299 |
} |
300 |
opt = cpu_to_be32(NBD_OPT_EXPORT_NAME); |
301 |
if (write_sync(csock, &opt, sizeof(opt)) != sizeof(opt)) { |
302 |
LOG("write failed (opt)");
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303 |
goto fail;
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304 |
} |
305 |
namesize = cpu_to_be32(strlen(name)); |
306 |
if (write_sync(csock, &namesize, sizeof(namesize)) != |
307 |
sizeof(namesize)) {
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308 |
LOG("write failed (namesize)");
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309 |
goto fail;
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310 |
} |
311 |
if (write_sync(csock, (char*)name, strlen(name)) != strlen(name)) { |
312 |
LOG("write failed (name)");
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313 |
goto fail;
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314 |
} |
315 |
} else {
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316 |
TRACE("Checking magic (cli_magic)");
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317 |
|
318 |
if (magic != 0x00420281861253LL) { |
319 |
LOG("Bad magic received");
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320 |
goto fail;
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321 |
} |
322 |
} |
323 |
|
324 |
if (read_sync(csock, &s, sizeof(s)) != sizeof(s)) { |
325 |
LOG("read failed");
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326 |
goto fail;
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327 |
} |
328 |
*size = be64_to_cpu(s); |
329 |
*blocksize = 1024;
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330 |
TRACE("Size is %" PRIu64, *size);
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331 |
|
332 |
if (!name) {
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333 |
if (read_sync(csock, flags, sizeof(*flags)) != sizeof(*flags)) { |
334 |
LOG("read failed (flags)");
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335 |
goto fail;
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336 |
} |
337 |
*flags = be32_to_cpup(flags); |
338 |
} else {
|
339 |
if (read_sync(csock, &tmp, sizeof(tmp)) != sizeof(tmp)) { |
340 |
LOG("read failed (tmp)");
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341 |
goto fail;
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342 |
} |
343 |
*flags |= be32_to_cpu(tmp); |
344 |
} |
345 |
if (read_sync(csock, &buf, 124) != 124) { |
346 |
LOG("read failed (buf)");
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347 |
goto fail;
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348 |
} |
349 |
rc = 0;
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350 |
|
351 |
fail:
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352 |
return rc;
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353 |
} |
354 |
|
355 |
#ifdef __linux__
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356 |
int nbd_init(int fd, int csock, uint32_t flags, off_t size, size_t blocksize) |
357 |
{ |
358 |
TRACE("Setting NBD socket");
|
359 |
|
360 |
if (ioctl(fd, NBD_SET_SOCK, csock) < 0) { |
361 |
int serrno = errno;
|
362 |
LOG("Failed to set NBD socket");
|
363 |
return -serrno;
|
364 |
} |
365 |
|
366 |
TRACE("Setting block size to %lu", (unsigned long)blocksize); |
367 |
|
368 |
if (ioctl(fd, NBD_SET_BLKSIZE, blocksize) < 0) { |
369 |
int serrno = errno;
|
370 |
LOG("Failed setting NBD block size");
|
371 |
return -serrno;
|
372 |
} |
373 |
|
374 |
TRACE("Setting size to %zd block(s)", (size_t)(size / blocksize));
|
375 |
|
376 |
if (ioctl(fd, NBD_SET_SIZE_BLOCKS, size / blocksize) < 0) { |
377 |
int serrno = errno;
|
378 |
LOG("Failed setting size (in blocks)");
|
379 |
return -serrno;
|
380 |
} |
381 |
|
382 |
if (flags & NBD_FLAG_READ_ONLY) {
|
383 |
int read_only = 1; |
384 |
TRACE("Setting readonly attribute");
|
385 |
|
386 |
if (ioctl(fd, BLKROSET, (unsigned long) &read_only) < 0) { |
387 |
int serrno = errno;
|
388 |
LOG("Failed setting read-only attribute");
|
389 |
return -serrno;
|
390 |
} |
391 |
} |
392 |
|
393 |
if (ioctl(fd, NBD_SET_FLAGS, flags) < 0 |
394 |
&& errno != ENOTTY) { |
395 |
int serrno = errno;
|
396 |
LOG("Failed setting flags");
|
397 |
return -serrno;
|
398 |
} |
399 |
|
400 |
TRACE("Negotiation ended");
|
401 |
|
402 |
return 0; |
403 |
} |
404 |
|
405 |
int nbd_disconnect(int fd) |
406 |
{ |
407 |
ioctl(fd, NBD_CLEAR_QUE); |
408 |
ioctl(fd, NBD_DISCONNECT); |
409 |
ioctl(fd, NBD_CLEAR_SOCK); |
410 |
return 0; |
411 |
} |
412 |
|
413 |
int nbd_client(int fd) |
414 |
{ |
415 |
int ret;
|
416 |
int serrno;
|
417 |
|
418 |
TRACE("Doing NBD loop");
|
419 |
|
420 |
ret = ioctl(fd, NBD_DO_IT); |
421 |
if (ret < 0 && errno == EPIPE) { |
422 |
/* NBD_DO_IT normally returns EPIPE when someone has disconnected
|
423 |
* the socket via NBD_DISCONNECT. We do not want to return 1 in
|
424 |
* that case.
|
425 |
*/
|
426 |
ret = 0;
|
427 |
} |
428 |
serrno = errno; |
429 |
|
430 |
TRACE("NBD loop returned %d: %s", ret, strerror(serrno));
|
431 |
|
432 |
TRACE("Clearing NBD queue");
|
433 |
ioctl(fd, NBD_CLEAR_QUE); |
434 |
|
435 |
TRACE("Clearing NBD socket");
|
436 |
ioctl(fd, NBD_CLEAR_SOCK); |
437 |
|
438 |
errno = serrno; |
439 |
return ret;
|
440 |
} |
441 |
#else
|
442 |
int nbd_init(int fd, int csock, uint32_t flags, off_t size, size_t blocksize) |
443 |
{ |
444 |
return -ENOTSUP;
|
445 |
} |
446 |
|
447 |
int nbd_disconnect(int fd) |
448 |
{ |
449 |
return -ENOTSUP;
|
450 |
} |
451 |
|
452 |
int nbd_client(int fd) |
453 |
{ |
454 |
return -ENOTSUP;
|
455 |
} |
456 |
#endif
|
457 |
|
458 |
ssize_t nbd_send_request(int csock, struct nbd_request *request) |
459 |
{ |
460 |
uint8_t buf[4 + 4 + 8 + 8 + 4]; |
461 |
ssize_t ret; |
462 |
|
463 |
cpu_to_be32w((uint32_t*)buf, NBD_REQUEST_MAGIC); |
464 |
cpu_to_be32w((uint32_t*)(buf + 4), request->type);
|
465 |
cpu_to_be64w((uint64_t*)(buf + 8), request->handle);
|
466 |
cpu_to_be64w((uint64_t*)(buf + 16), request->from);
|
467 |
cpu_to_be32w((uint32_t*)(buf + 24), request->len);
|
468 |
|
469 |
TRACE("Sending request to client: "
|
470 |
"{ .from = %" PRIu64", .len = %u, .handle = %" PRIu64", .type=%i}", |
471 |
request->from, request->len, request->handle, request->type); |
472 |
|
473 |
ret = write_sync(csock, buf, sizeof(buf));
|
474 |
if (ret < 0) { |
475 |
return ret;
|
476 |
} |
477 |
|
478 |
if (ret != sizeof(buf)) { |
479 |
LOG("writing to socket failed");
|
480 |
return -EINVAL;
|
481 |
} |
482 |
return 0; |
483 |
} |
484 |
|
485 |
static ssize_t nbd_receive_request(int csock, struct nbd_request *request) |
486 |
{ |
487 |
uint8_t buf[4 + 4 + 8 + 8 + 4]; |
488 |
uint32_t magic; |
489 |
ssize_t ret; |
490 |
|
491 |
ret = read_sync(csock, buf, sizeof(buf));
|
492 |
if (ret < 0) { |
493 |
return ret;
|
494 |
} |
495 |
|
496 |
if (ret != sizeof(buf)) { |
497 |
LOG("read failed");
|
498 |
return -EINVAL;
|
499 |
} |
500 |
|
501 |
/* Request
|
502 |
[ 0 .. 3] magic (NBD_REQUEST_MAGIC)
|
503 |
[ 4 .. 7] type (0 == READ, 1 == WRITE)
|
504 |
[ 8 .. 15] handle
|
505 |
[16 .. 23] from
|
506 |
[24 .. 27] len
|
507 |
*/
|
508 |
|
509 |
magic = be32_to_cpup((uint32_t*)buf); |
510 |
request->type = be32_to_cpup((uint32_t*)(buf + 4));
|
511 |
request->handle = be64_to_cpup((uint64_t*)(buf + 8));
|
512 |
request->from = be64_to_cpup((uint64_t*)(buf + 16));
|
513 |
request->len = be32_to_cpup((uint32_t*)(buf + 24));
|
514 |
|
515 |
TRACE("Got request: "
|
516 |
"{ magic = 0x%x, .type = %d, from = %" PRIu64" , len = %u }", |
517 |
magic, request->type, request->from, request->len); |
518 |
|
519 |
if (magic != NBD_REQUEST_MAGIC) {
|
520 |
LOG("invalid magic (got 0x%x)", magic);
|
521 |
return -EINVAL;
|
522 |
} |
523 |
return 0; |
524 |
} |
525 |
|
526 |
ssize_t nbd_receive_reply(int csock, struct nbd_reply *reply) |
527 |
{ |
528 |
uint8_t buf[NBD_REPLY_SIZE]; |
529 |
uint32_t magic; |
530 |
ssize_t ret; |
531 |
|
532 |
ret = read_sync(csock, buf, sizeof(buf));
|
533 |
if (ret < 0) { |
534 |
return ret;
|
535 |
} |
536 |
|
537 |
if (ret != sizeof(buf)) { |
538 |
LOG("read failed");
|
539 |
return -EINVAL;
|
540 |
} |
541 |
|
542 |
/* Reply
|
543 |
[ 0 .. 3] magic (NBD_REPLY_MAGIC)
|
544 |
[ 4 .. 7] error (0 == no error)
|
545 |
[ 7 .. 15] handle
|
546 |
*/
|
547 |
|
548 |
magic = be32_to_cpup((uint32_t*)buf); |
549 |
reply->error = be32_to_cpup((uint32_t*)(buf + 4));
|
550 |
reply->handle = be64_to_cpup((uint64_t*)(buf + 8));
|
551 |
|
552 |
TRACE("Got reply: "
|
553 |
"{ magic = 0x%x, .error = %d, handle = %" PRIu64" }", |
554 |
magic, reply->error, reply->handle); |
555 |
|
556 |
if (magic != NBD_REPLY_MAGIC) {
|
557 |
LOG("invalid magic (got 0x%x)", magic);
|
558 |
return -EINVAL;
|
559 |
} |
560 |
return 0; |
561 |
} |
562 |
|
563 |
static ssize_t nbd_send_reply(int csock, struct nbd_reply *reply) |
564 |
{ |
565 |
uint8_t buf[4 + 4 + 8]; |
566 |
ssize_t ret; |
567 |
|
568 |
/* Reply
|
569 |
[ 0 .. 3] magic (NBD_REPLY_MAGIC)
|
570 |
[ 4 .. 7] error (0 == no error)
|
571 |
[ 7 .. 15] handle
|
572 |
*/
|
573 |
cpu_to_be32w((uint32_t*)buf, NBD_REPLY_MAGIC); |
574 |
cpu_to_be32w((uint32_t*)(buf + 4), reply->error);
|
575 |
cpu_to_be64w((uint64_t*)(buf + 8), reply->handle);
|
576 |
|
577 |
TRACE("Sending response to client");
|
578 |
|
579 |
ret = write_sync(csock, buf, sizeof(buf));
|
580 |
if (ret < 0) { |
581 |
return ret;
|
582 |
} |
583 |
|
584 |
if (ret != sizeof(buf)) { |
585 |
LOG("writing to socket failed");
|
586 |
return -EINVAL;
|
587 |
} |
588 |
return 0; |
589 |
} |
590 |
|
591 |
#define MAX_NBD_REQUESTS 16 |
592 |
|
593 |
typedef struct NBDRequest NBDRequest; |
594 |
|
595 |
struct NBDRequest {
|
596 |
QSIMPLEQ_ENTRY(NBDRequest) entry; |
597 |
NBDClient *client; |
598 |
uint8_t *data; |
599 |
}; |
600 |
|
601 |
struct NBDExport {
|
602 |
BlockDriverState *bs; |
603 |
off_t dev_offset; |
604 |
off_t size; |
605 |
uint32_t nbdflags; |
606 |
QSIMPLEQ_HEAD(, NBDRequest) requests; |
607 |
}; |
608 |
|
609 |
struct NBDClient {
|
610 |
int refcount;
|
611 |
void (*close)(NBDClient *client);
|
612 |
|
613 |
NBDExport *exp; |
614 |
int sock;
|
615 |
|
616 |
Coroutine *recv_coroutine; |
617 |
|
618 |
CoMutex send_lock; |
619 |
Coroutine *send_coroutine; |
620 |
|
621 |
int nb_requests;
|
622 |
}; |
623 |
|
624 |
static void nbd_client_get(NBDClient *client) |
625 |
{ |
626 |
client->refcount++; |
627 |
} |
628 |
|
629 |
static void nbd_client_put(NBDClient *client) |
630 |
{ |
631 |
if (--client->refcount == 0) { |
632 |
g_free(client); |
633 |
} |
634 |
} |
635 |
|
636 |
static void nbd_client_close(NBDClient *client) |
637 |
{ |
638 |
qemu_set_fd_handler2(client->sock, NULL, NULL, NULL, NULL); |
639 |
close(client->sock); |
640 |
client->sock = -1;
|
641 |
if (client->close) {
|
642 |
client->close(client); |
643 |
} |
644 |
nbd_client_put(client); |
645 |
} |
646 |
|
647 |
static NBDRequest *nbd_request_get(NBDClient *client)
|
648 |
{ |
649 |
NBDRequest *req; |
650 |
NBDExport *exp = client->exp; |
651 |
|
652 |
assert(client->nb_requests <= MAX_NBD_REQUESTS - 1);
|
653 |
client->nb_requests++; |
654 |
|
655 |
if (QSIMPLEQ_EMPTY(&exp->requests)) {
|
656 |
req = g_malloc0(sizeof(NBDRequest));
|
657 |
req->data = qemu_blockalign(exp->bs, NBD_BUFFER_SIZE); |
658 |
} else {
|
659 |
req = QSIMPLEQ_FIRST(&exp->requests); |
660 |
QSIMPLEQ_REMOVE_HEAD(&exp->requests, entry); |
661 |
} |
662 |
nbd_client_get(client); |
663 |
req->client = client; |
664 |
return req;
|
665 |
} |
666 |
|
667 |
static void nbd_request_put(NBDRequest *req) |
668 |
{ |
669 |
NBDClient *client = req->client; |
670 |
QSIMPLEQ_INSERT_HEAD(&client->exp->requests, req, entry); |
671 |
if (client->nb_requests-- == MAX_NBD_REQUESTS) {
|
672 |
qemu_notify_event(); |
673 |
} |
674 |
nbd_client_put(client); |
675 |
} |
676 |
|
677 |
NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset, |
678 |
off_t size, uint32_t nbdflags) |
679 |
{ |
680 |
NBDExport *exp = g_malloc0(sizeof(NBDExport));
|
681 |
QSIMPLEQ_INIT(&exp->requests); |
682 |
exp->bs = bs; |
683 |
exp->dev_offset = dev_offset; |
684 |
exp->nbdflags = nbdflags; |
685 |
exp->size = size == -1 ? exp->bs->total_sectors * 512 : size; |
686 |
return exp;
|
687 |
} |
688 |
|
689 |
void nbd_export_close(NBDExport *exp)
|
690 |
{ |
691 |
while (!QSIMPLEQ_EMPTY(&exp->requests)) {
|
692 |
NBDRequest *first = QSIMPLEQ_FIRST(&exp->requests); |
693 |
QSIMPLEQ_REMOVE_HEAD(&exp->requests, entry); |
694 |
qemu_vfree(first->data); |
695 |
g_free(first); |
696 |
} |
697 |
|
698 |
bdrv_close(exp->bs); |
699 |
g_free(exp); |
700 |
} |
701 |
|
702 |
static int nbd_can_read(void *opaque); |
703 |
static void nbd_read(void *opaque); |
704 |
static void nbd_restart_write(void *opaque); |
705 |
|
706 |
static ssize_t nbd_co_send_reply(NBDRequest *req, struct nbd_reply *reply, |
707 |
int len)
|
708 |
{ |
709 |
NBDClient *client = req->client; |
710 |
int csock = client->sock;
|
711 |
ssize_t rc, ret; |
712 |
|
713 |
qemu_co_mutex_lock(&client->send_lock); |
714 |
qemu_set_fd_handler2(csock, nbd_can_read, nbd_read, |
715 |
nbd_restart_write, client); |
716 |
client->send_coroutine = qemu_coroutine_self(); |
717 |
|
718 |
if (!len) {
|
719 |
rc = nbd_send_reply(csock, reply); |
720 |
} else {
|
721 |
socket_set_cork(csock, 1);
|
722 |
rc = nbd_send_reply(csock, reply); |
723 |
if (rc >= 0) { |
724 |
ret = qemu_co_send(csock, req->data, len); |
725 |
if (ret != len) {
|
726 |
rc = -EIO; |
727 |
} |
728 |
} |
729 |
socket_set_cork(csock, 0);
|
730 |
} |
731 |
|
732 |
client->send_coroutine = NULL;
|
733 |
qemu_set_fd_handler2(csock, nbd_can_read, nbd_read, NULL, client);
|
734 |
qemu_co_mutex_unlock(&client->send_lock); |
735 |
return rc;
|
736 |
} |
737 |
|
738 |
static ssize_t nbd_co_receive_request(NBDRequest *req, struct nbd_request *request) |
739 |
{ |
740 |
NBDClient *client = req->client; |
741 |
int csock = client->sock;
|
742 |
ssize_t rc; |
743 |
|
744 |
client->recv_coroutine = qemu_coroutine_self(); |
745 |
if (nbd_receive_request(csock, request) < 0) { |
746 |
rc = -EIO; |
747 |
goto out;
|
748 |
} |
749 |
|
750 |
if (request->len > NBD_BUFFER_SIZE) {
|
751 |
LOG("len (%u) is larger than max len (%u)",
|
752 |
request->len, NBD_BUFFER_SIZE); |
753 |
rc = -EINVAL; |
754 |
goto out;
|
755 |
} |
756 |
|
757 |
if ((request->from + request->len) < request->from) {
|
758 |
LOG("integer overflow detected! "
|
759 |
"you're probably being attacked");
|
760 |
rc = -EINVAL; |
761 |
goto out;
|
762 |
} |
763 |
|
764 |
TRACE("Decoding type");
|
765 |
|
766 |
if ((request->type & NBD_CMD_MASK_COMMAND) == NBD_CMD_WRITE) {
|
767 |
TRACE("Reading %u byte(s)", request->len);
|
768 |
|
769 |
if (qemu_co_recv(csock, req->data, request->len) != request->len) {
|
770 |
LOG("reading from socket failed");
|
771 |
rc = -EIO; |
772 |
goto out;
|
773 |
} |
774 |
} |
775 |
rc = 0;
|
776 |
|
777 |
out:
|
778 |
client->recv_coroutine = NULL;
|
779 |
return rc;
|
780 |
} |
781 |
|
782 |
static void nbd_trip(void *opaque) |
783 |
{ |
784 |
NBDClient *client = opaque; |
785 |
NBDRequest *req = nbd_request_get(client); |
786 |
NBDExport *exp = client->exp; |
787 |
struct nbd_request request;
|
788 |
struct nbd_reply reply;
|
789 |
ssize_t ret; |
790 |
|
791 |
TRACE("Reading request.");
|
792 |
|
793 |
ret = nbd_co_receive_request(req, &request); |
794 |
if (ret == -EIO) {
|
795 |
goto out;
|
796 |
} |
797 |
|
798 |
reply.handle = request.handle; |
799 |
reply.error = 0;
|
800 |
|
801 |
if (ret < 0) { |
802 |
reply.error = -ret; |
803 |
goto error_reply;
|
804 |
} |
805 |
|
806 |
if ((request.from + request.len) > exp->size) {
|
807 |
LOG("From: %" PRIu64 ", Len: %u, Size: %" PRIu64 |
808 |
", Offset: %" PRIu64 "\n", |
809 |
request.from, request.len, |
810 |
(uint64_t)exp->size, (uint64_t)exp->dev_offset); |
811 |
LOG("requested operation past EOF--bad client?");
|
812 |
goto invalid_request;
|
813 |
} |
814 |
|
815 |
switch (request.type & NBD_CMD_MASK_COMMAND) {
|
816 |
case NBD_CMD_READ:
|
817 |
TRACE("Request type is READ");
|
818 |
|
819 |
ret = bdrv_read(exp->bs, (request.from + exp->dev_offset) / 512,
|
820 |
req->data, request.len / 512);
|
821 |
if (ret < 0) { |
822 |
LOG("reading from file failed");
|
823 |
reply.error = -ret; |
824 |
goto error_reply;
|
825 |
} |
826 |
|
827 |
TRACE("Read %u byte(s)", request.len);
|
828 |
if (nbd_co_send_reply(req, &reply, request.len) < 0) |
829 |
goto out;
|
830 |
break;
|
831 |
case NBD_CMD_WRITE:
|
832 |
TRACE("Request type is WRITE");
|
833 |
|
834 |
if (exp->nbdflags & NBD_FLAG_READ_ONLY) {
|
835 |
TRACE("Server is read-only, return error");
|
836 |
reply.error = EROFS; |
837 |
goto error_reply;
|
838 |
} |
839 |
|
840 |
TRACE("Writing to device");
|
841 |
|
842 |
ret = bdrv_write(exp->bs, (request.from + exp->dev_offset) / 512,
|
843 |
req->data, request.len / 512);
|
844 |
if (ret < 0) { |
845 |
LOG("writing to file failed");
|
846 |
reply.error = -ret; |
847 |
goto error_reply;
|
848 |
} |
849 |
|
850 |
if (request.type & NBD_CMD_FLAG_FUA) {
|
851 |
ret = bdrv_co_flush(exp->bs); |
852 |
if (ret < 0) { |
853 |
LOG("flush failed");
|
854 |
reply.error = -ret; |
855 |
goto error_reply;
|
856 |
} |
857 |
} |
858 |
|
859 |
if (nbd_co_send_reply(req, &reply, 0) < 0) { |
860 |
goto out;
|
861 |
} |
862 |
break;
|
863 |
case NBD_CMD_DISC:
|
864 |
TRACE("Request type is DISCONNECT");
|
865 |
errno = 0;
|
866 |
goto out;
|
867 |
case NBD_CMD_FLUSH:
|
868 |
TRACE("Request type is FLUSH");
|
869 |
|
870 |
ret = bdrv_co_flush(exp->bs); |
871 |
if (ret < 0) { |
872 |
LOG("flush failed");
|
873 |
reply.error = -ret; |
874 |
} |
875 |
if (nbd_co_send_reply(req, &reply, 0) < 0) { |
876 |
goto out;
|
877 |
} |
878 |
break;
|
879 |
case NBD_CMD_TRIM:
|
880 |
TRACE("Request type is TRIM");
|
881 |
ret = bdrv_co_discard(exp->bs, (request.from + exp->dev_offset) / 512,
|
882 |
request.len / 512);
|
883 |
if (ret < 0) { |
884 |
LOG("discard failed");
|
885 |
reply.error = -ret; |
886 |
} |
887 |
if (nbd_co_send_reply(req, &reply, 0) < 0) { |
888 |
goto out;
|
889 |
} |
890 |
break;
|
891 |
default:
|
892 |
LOG("invalid request type (%u) received", request.type);
|
893 |
invalid_request:
|
894 |
reply.error = -EINVAL; |
895 |
error_reply:
|
896 |
if (nbd_co_send_reply(req, &reply, 0) < 0) { |
897 |
goto out;
|
898 |
} |
899 |
break;
|
900 |
} |
901 |
|
902 |
TRACE("Request/Reply complete");
|
903 |
|
904 |
nbd_request_put(req); |
905 |
return;
|
906 |
|
907 |
out:
|
908 |
nbd_request_put(req); |
909 |
nbd_client_close(client); |
910 |
} |
911 |
|
912 |
static int nbd_can_read(void *opaque) |
913 |
{ |
914 |
NBDClient *client = opaque; |
915 |
|
916 |
return client->recv_coroutine || client->nb_requests < MAX_NBD_REQUESTS;
|
917 |
} |
918 |
|
919 |
static void nbd_read(void *opaque) |
920 |
{ |
921 |
NBDClient *client = opaque; |
922 |
|
923 |
if (client->recv_coroutine) {
|
924 |
qemu_coroutine_enter(client->recv_coroutine, NULL);
|
925 |
} else {
|
926 |
qemu_coroutine_enter(qemu_coroutine_create(nbd_trip), client); |
927 |
} |
928 |
} |
929 |
|
930 |
static void nbd_restart_write(void *opaque) |
931 |
{ |
932 |
NBDClient *client = opaque; |
933 |
|
934 |
qemu_coroutine_enter(client->send_coroutine, NULL);
|
935 |
} |
936 |
|
937 |
NBDClient *nbd_client_new(NBDExport *exp, int csock,
|
938 |
void (*close)(NBDClient *))
|
939 |
{ |
940 |
NBDClient *client; |
941 |
if (nbd_send_negotiate(csock, exp->size, exp->nbdflags) < 0) { |
942 |
return NULL; |
943 |
} |
944 |
client = g_malloc0(sizeof(NBDClient));
|
945 |
client->refcount = 1;
|
946 |
client->exp = exp; |
947 |
client->sock = csock; |
948 |
client->close = close; |
949 |
qemu_co_mutex_init(&client->send_lock); |
950 |
qemu_set_fd_handler2(csock, nbd_can_read, nbd_read, NULL, client);
|
951 |
return client;
|
952 |
} |