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-rw-r--r--qemu/block/nbd-client.c436
1 files changed, 0 insertions, 436 deletions
diff --git a/qemu/block/nbd-client.c b/qemu/block/nbd-client.c
deleted file mode 100644
index 878e879ac..000000000
--- a/qemu/block/nbd-client.c
+++ /dev/null
@@ -1,436 +0,0 @@
-/*
- * QEMU Block driver for NBD
- *
- * Copyright (C) 2008 Bull S.A.S.
- * Author: Laurent Vivier <Laurent.Vivier@bull.net>
- *
- * Some parts:
- * Copyright (C) 2007 Anthony Liguori <anthony@codemonkey.ws>
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
- * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
-
-#include "qemu/osdep.h"
-#include "nbd-client.h"
-
-#define HANDLE_TO_INDEX(bs, handle) ((handle) ^ ((uint64_t)(intptr_t)bs))
-#define INDEX_TO_HANDLE(bs, index) ((index) ^ ((uint64_t)(intptr_t)bs))
-
-static void nbd_recv_coroutines_enter_all(NbdClientSession *s)
-{
- int i;
-
- for (i = 0; i < MAX_NBD_REQUESTS; i++) {
- if (s->recv_coroutine[i]) {
- qemu_coroutine_enter(s->recv_coroutine[i], NULL);
- }
- }
-}
-
-static void nbd_teardown_connection(BlockDriverState *bs)
-{
- NbdClientSession *client = nbd_get_client_session(bs);
-
- if (!client->ioc) { /* Already closed */
- return;
- }
-
- /* finish any pending coroutines */
- qio_channel_shutdown(client->ioc,
- QIO_CHANNEL_SHUTDOWN_BOTH,
- NULL);
- nbd_recv_coroutines_enter_all(client);
-
- nbd_client_detach_aio_context(bs);
- object_unref(OBJECT(client->sioc));
- client->sioc = NULL;
- object_unref(OBJECT(client->ioc));
- client->ioc = NULL;
-}
-
-static void nbd_reply_ready(void *opaque)
-{
- BlockDriverState *bs = opaque;
- NbdClientSession *s = nbd_get_client_session(bs);
- uint64_t i;
- int ret;
-
- if (!s->ioc) { /* Already closed */
- return;
- }
-
- if (s->reply.handle == 0) {
- /* No reply already in flight. Fetch a header. It is possible
- * that another thread has done the same thing in parallel, so
- * the socket is not readable anymore.
- */
- ret = nbd_receive_reply(s->ioc, &s->reply);
- if (ret == -EAGAIN) {
- return;
- }
- if (ret < 0) {
- s->reply.handle = 0;
- goto fail;
- }
- }
-
- /* There's no need for a mutex on the receive side, because the
- * handler acts as a synchronization point and ensures that only
- * one coroutine is called until the reply finishes. */
- i = HANDLE_TO_INDEX(s, s->reply.handle);
- if (i >= MAX_NBD_REQUESTS) {
- goto fail;
- }
-
- if (s->recv_coroutine[i]) {
- qemu_coroutine_enter(s->recv_coroutine[i], NULL);
- return;
- }
-
-fail:
- nbd_teardown_connection(bs);
-}
-
-static void nbd_restart_write(void *opaque)
-{
- BlockDriverState *bs = opaque;
-
- qemu_coroutine_enter(nbd_get_client_session(bs)->send_coroutine, NULL);
-}
-
-static int nbd_co_send_request(BlockDriverState *bs,
- struct nbd_request *request,
- QEMUIOVector *qiov, int offset)
-{
- NbdClientSession *s = nbd_get_client_session(bs);
- AioContext *aio_context;
- int rc, ret, i;
-
- qemu_co_mutex_lock(&s->send_mutex);
-
- for (i = 0; i < MAX_NBD_REQUESTS; i++) {
- if (s->recv_coroutine[i] == NULL) {
- s->recv_coroutine[i] = qemu_coroutine_self();
- break;
- }
- }
-
- g_assert(qemu_in_coroutine());
- assert(i < MAX_NBD_REQUESTS);
- request->handle = INDEX_TO_HANDLE(s, i);
-
- if (!s->ioc) {
- qemu_co_mutex_unlock(&s->send_mutex);
- return -EPIPE;
- }
-
- s->send_coroutine = qemu_coroutine_self();
- aio_context = bdrv_get_aio_context(bs);
-
- aio_set_fd_handler(aio_context, s->sioc->fd, false,
- nbd_reply_ready, nbd_restart_write, bs);
- if (qiov) {
- qio_channel_set_cork(s->ioc, true);
- rc = nbd_send_request(s->ioc, request);
- if (rc >= 0) {
- ret = nbd_wr_syncv(s->ioc, qiov->iov, qiov->niov,
- offset, request->len, 0);
- if (ret != request->len) {
- rc = -EIO;
- }
- }
- qio_channel_set_cork(s->ioc, false);
- } else {
- rc = nbd_send_request(s->ioc, request);
- }
- aio_set_fd_handler(aio_context, s->sioc->fd, false,
- nbd_reply_ready, NULL, bs);
- s->send_coroutine = NULL;
- qemu_co_mutex_unlock(&s->send_mutex);
- return rc;
-}
-
-static void nbd_co_receive_reply(NbdClientSession *s,
- struct nbd_request *request, struct nbd_reply *reply,
- QEMUIOVector *qiov, int offset)
-{
- int ret;
-
- /* Wait until we're woken up by the read handler. TODO: perhaps
- * peek at the next reply and avoid yielding if it's ours? */
- qemu_coroutine_yield();
- *reply = s->reply;
- if (reply->handle != request->handle ||
- !s->ioc) {
- reply->error = EIO;
- } else {
- if (qiov && reply->error == 0) {
- ret = nbd_wr_syncv(s->ioc, qiov->iov, qiov->niov,
- offset, request->len, 1);
- if (ret != request->len) {
- reply->error = EIO;
- }
- }
-
- /* Tell the read handler to read another header. */
- s->reply.handle = 0;
- }
-}
-
-static void nbd_coroutine_start(NbdClientSession *s,
- struct nbd_request *request)
-{
- /* Poor man semaphore. The free_sema is locked when no other request
- * can be accepted, and unlocked after receiving one reply. */
- if (s->in_flight >= MAX_NBD_REQUESTS - 1) {
- qemu_co_mutex_lock(&s->free_sema);
- assert(s->in_flight < MAX_NBD_REQUESTS);
- }
- s->in_flight++;
-
- /* s->recv_coroutine[i] is set as soon as we get the send_lock. */
-}
-
-static void nbd_coroutine_end(NbdClientSession *s,
- struct nbd_request *request)
-{
- int i = HANDLE_TO_INDEX(s, request->handle);
- s->recv_coroutine[i] = NULL;
- if (s->in_flight-- == MAX_NBD_REQUESTS) {
- qemu_co_mutex_unlock(&s->free_sema);
- }
-}
-
-static int nbd_co_readv_1(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, QEMUIOVector *qiov,
- int offset)
-{
- NbdClientSession *client = nbd_get_client_session(bs);
- struct nbd_request request = { .type = NBD_CMD_READ };
- struct nbd_reply reply;
- ssize_t ret;
-
- request.from = sector_num * 512;
- request.len = nb_sectors * 512;
-
- nbd_coroutine_start(client, &request);
- ret = nbd_co_send_request(bs, &request, NULL, 0);
- if (ret < 0) {
- reply.error = -ret;
- } else {
- nbd_co_receive_reply(client, &request, &reply, qiov, offset);
- }
- nbd_coroutine_end(client, &request);
- return -reply.error;
-
-}
-
-static int nbd_co_writev_1(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, QEMUIOVector *qiov,
- int offset, int *flags)
-{
- NbdClientSession *client = nbd_get_client_session(bs);
- struct nbd_request request = { .type = NBD_CMD_WRITE };
- struct nbd_reply reply;
- ssize_t ret;
-
- if ((*flags & BDRV_REQ_FUA) && (client->nbdflags & NBD_FLAG_SEND_FUA)) {
- *flags &= ~BDRV_REQ_FUA;
- request.type |= NBD_CMD_FLAG_FUA;
- }
-
- request.from = sector_num * 512;
- request.len = nb_sectors * 512;
-
- nbd_coroutine_start(client, &request);
- ret = nbd_co_send_request(bs, &request, qiov, offset);
- if (ret < 0) {
- reply.error = -ret;
- } else {
- nbd_co_receive_reply(client, &request, &reply, NULL, 0);
- }
- nbd_coroutine_end(client, &request);
- return -reply.error;
-}
-
-/* qemu-nbd has a limit of slightly less than 1M per request. Try to
- * remain aligned to 4K. */
-#define NBD_MAX_SECTORS 2040
-
-int nbd_client_co_readv(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, QEMUIOVector *qiov)
-{
- int offset = 0;
- int ret;
- while (nb_sectors > NBD_MAX_SECTORS) {
- ret = nbd_co_readv_1(bs, sector_num, NBD_MAX_SECTORS, qiov, offset);
- if (ret < 0) {
- return ret;
- }
- offset += NBD_MAX_SECTORS * 512;
- sector_num += NBD_MAX_SECTORS;
- nb_sectors -= NBD_MAX_SECTORS;
- }
- return nbd_co_readv_1(bs, sector_num, nb_sectors, qiov, offset);
-}
-
-int nbd_client_co_writev(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors, QEMUIOVector *qiov, int *flags)
-{
- int offset = 0;
- int ret;
- while (nb_sectors > NBD_MAX_SECTORS) {
- ret = nbd_co_writev_1(bs, sector_num, NBD_MAX_SECTORS, qiov, offset,
- flags);
- if (ret < 0) {
- return ret;
- }
- offset += NBD_MAX_SECTORS * 512;
- sector_num += NBD_MAX_SECTORS;
- nb_sectors -= NBD_MAX_SECTORS;
- }
- return nbd_co_writev_1(bs, sector_num, nb_sectors, qiov, offset, flags);
-}
-
-int nbd_client_co_flush(BlockDriverState *bs)
-{
- NbdClientSession *client = nbd_get_client_session(bs);
- struct nbd_request request = { .type = NBD_CMD_FLUSH };
- struct nbd_reply reply;
- ssize_t ret;
-
- if (!(client->nbdflags & NBD_FLAG_SEND_FLUSH)) {
- return 0;
- }
-
- request.from = 0;
- request.len = 0;
-
- nbd_coroutine_start(client, &request);
- ret = nbd_co_send_request(bs, &request, NULL, 0);
- if (ret < 0) {
- reply.error = -ret;
- } else {
- nbd_co_receive_reply(client, &request, &reply, NULL, 0);
- }
- nbd_coroutine_end(client, &request);
- return -reply.error;
-}
-
-int nbd_client_co_discard(BlockDriverState *bs, int64_t sector_num,
- int nb_sectors)
-{
- NbdClientSession *client = nbd_get_client_session(bs);
- struct nbd_request request = { .type = NBD_CMD_TRIM };
- struct nbd_reply reply;
- ssize_t ret;
-
- if (!(client->nbdflags & NBD_FLAG_SEND_TRIM)) {
- return 0;
- }
- request.from = sector_num * 512;
- request.len = nb_sectors * 512;
-
- nbd_coroutine_start(client, &request);
- ret = nbd_co_send_request(bs, &request, NULL, 0);
- if (ret < 0) {
- reply.error = -ret;
- } else {
- nbd_co_receive_reply(client, &request, &reply, NULL, 0);
- }
- nbd_coroutine_end(client, &request);
- return -reply.error;
-
-}
-
-void nbd_client_detach_aio_context(BlockDriverState *bs)
-{
- aio_set_fd_handler(bdrv_get_aio_context(bs),
- nbd_get_client_session(bs)->sioc->fd,
- false, NULL, NULL, NULL);
-}
-
-void nbd_client_attach_aio_context(BlockDriverState *bs,
- AioContext *new_context)
-{
- aio_set_fd_handler(new_context, nbd_get_client_session(bs)->sioc->fd,
- false, nbd_reply_ready, NULL, bs);
-}
-
-void nbd_client_close(BlockDriverState *bs)
-{
- NbdClientSession *client = nbd_get_client_session(bs);
- struct nbd_request request = {
- .type = NBD_CMD_DISC,
- .from = 0,
- .len = 0
- };
-
- if (client->ioc == NULL) {
- return;
- }
-
- nbd_send_request(client->ioc, &request);
-
- nbd_teardown_connection(bs);
-}
-
-int nbd_client_init(BlockDriverState *bs,
- QIOChannelSocket *sioc,
- const char *export,
- QCryptoTLSCreds *tlscreds,
- const char *hostname,
- Error **errp)
-{
- NbdClientSession *client = nbd_get_client_session(bs);
- int ret;
-
- /* NBD handshake */
- logout("session init %s\n", export);
- qio_channel_set_blocking(QIO_CHANNEL(sioc), true, NULL);
-
- ret = nbd_receive_negotiate(QIO_CHANNEL(sioc), export,
- &client->nbdflags,
- tlscreds, hostname,
- &client->ioc,
- &client->size, errp);
- if (ret < 0) {
- logout("Failed to negotiate with the NBD server\n");
- return ret;
- }
-
- qemu_co_mutex_init(&client->send_mutex);
- qemu_co_mutex_init(&client->free_sema);
- client->sioc = sioc;
- object_ref(OBJECT(client->sioc));
-
- if (!client->ioc) {
- client->ioc = QIO_CHANNEL(sioc);
- object_ref(OBJECT(client->ioc));
- }
-
- /* Now that we're connected, set the socket to be non-blocking and
- * kick the reply mechanism. */
- qio_channel_set_blocking(QIO_CHANNEL(sioc), false, NULL);
-
- nbd_client_attach_aio_context(bs, bdrv_get_aio_context(bs));
-
- logout("Established connection with NBD server\n");
- return 0;
-}