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-rw-r--r--block/nbd.c196
1 files changed, 196 insertions, 0 deletions
diff --git a/block/nbd.c b/block/nbd.c
new file mode 100644
index 0000000..47d4778
--- /dev/null
+++ b/block/nbd.c
@@ -0,0 +1,196 @@
+/*
+ * 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-common.h"
+#include "nbd.h"
+#include "module.h"
+
+#include <sys/types.h>
+#include <unistd.h>
+
+typedef struct BDRVNBDState {
+ int sock;
+ off_t size;
+ size_t blocksize;
+} BDRVNBDState;
+
+static int nbd_open(BlockDriverState *bs, const char* filename, int flags)
+{
+ BDRVNBDState *s = bs->opaque;
+ const char *host;
+ const char *unixpath;
+ int sock;
+ off_t size;
+ size_t blocksize;
+ int ret;
+
+ if ((flags & BDRV_O_CREAT))
+ return -EINVAL;
+
+ if (!strstart(filename, "nbd:", &host))
+ return -EINVAL;
+
+ if (strstart(host, "unix:", &unixpath)) {
+
+ if (unixpath[0] != '/')
+ return -EINVAL;
+
+ sock = unix_socket_outgoing(unixpath);
+
+ } else {
+ uint16_t port;
+ char *p, *r;
+ char hostname[128];
+
+ pstrcpy(hostname, 128, host);
+
+ p = strchr(hostname, ':');
+ if (p == NULL)
+ return -EINVAL;
+
+ *p = '\0';
+ p++;
+
+ port = strtol(p, &r, 0);
+ if (r == p)
+ return -EINVAL;
+ sock = tcp_socket_outgoing(hostname, port);
+ }
+
+ if (sock == -1)
+ return -errno;
+
+ ret = nbd_receive_negotiate(sock, &size, &blocksize);
+ if (ret == -1)
+ return -errno;
+
+ s->sock = sock;
+ s->size = size;
+ s->blocksize = blocksize;
+
+ return 0;
+}
+
+static int nbd_read(BlockDriverState *bs, int64_t sector_num,
+ uint8_t *buf, int nb_sectors)
+{
+ BDRVNBDState *s = bs->opaque;
+ struct nbd_request request;
+ struct nbd_reply reply;
+
+ request.type = NBD_CMD_READ;
+ request.handle = (uint64_t)(intptr_t)bs;
+ request.from = sector_num * 512;;
+ request.len = nb_sectors * 512;
+
+ if (nbd_send_request(s->sock, &request) == -1)
+ return -errno;
+
+ if (nbd_receive_reply(s->sock, &reply) == -1)
+ return -errno;
+
+ if (reply.error !=0)
+ return -reply.error;
+
+ if (reply.handle != request.handle)
+ return -EIO;
+
+ if (nbd_wr_sync(s->sock, buf, request.len, 1) != request.len)
+ return -EIO;
+
+ return 0;
+}
+
+static int nbd_write(BlockDriverState *bs, int64_t sector_num,
+ const uint8_t *buf, int nb_sectors)
+{
+ BDRVNBDState *s = bs->opaque;
+ struct nbd_request request;
+ struct nbd_reply reply;
+
+ request.type = NBD_CMD_WRITE;
+ request.handle = (uint64_t)(intptr_t)bs;
+ request.from = sector_num * 512;;
+ request.len = nb_sectors * 512;
+
+ if (nbd_send_request(s->sock, &request) == -1)
+ return -errno;
+
+ if (nbd_wr_sync(s->sock, (uint8_t*)buf, request.len, 0) != request.len)
+ return -EIO;
+
+ if (nbd_receive_reply(s->sock, &reply) == -1)
+ return -errno;
+
+ if (reply.error !=0)
+ return -reply.error;
+
+ if (reply.handle != request.handle)
+ return -EIO;
+
+ return 0;
+}
+
+static void nbd_close(BlockDriverState *bs)
+{
+ BDRVNBDState *s = bs->opaque;
+ struct nbd_request request;
+
+ request.type = NBD_CMD_DISC;
+ request.handle = (uint64_t)(intptr_t)bs;
+ request.from = 0;
+ request.len = 0;
+ nbd_send_request(s->sock, &request);
+
+ close(s->sock);
+}
+
+static int64_t nbd_getlength(BlockDriverState *bs)
+{
+ BDRVNBDState *s = bs->opaque;
+
+ return s->size;
+}
+
+static BlockDriver bdrv_nbd = {
+ .format_name = "nbd",
+ .instance_size = sizeof(BDRVNBDState),
+ .bdrv_open = nbd_open,
+ .bdrv_read = nbd_read,
+ .bdrv_write = nbd_write,
+ .bdrv_close = nbd_close,
+ .bdrv_getlength = nbd_getlength,
+ .protocol_name = "nbd",
+};
+
+static void bdrv_nbd_init(void)
+{
+ bdrv_register(&bdrv_nbd);
+}
+
+block_init(bdrv_nbd_init);