qemu-nbd: introduce NBDExport
Wrap the common parameters of nbd_trip and nbd_negotiate in a
single opaque struct.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/nbd.c b/nbd.c
index 964a732..8d2a3bc 100644
--- a/nbd.c
+++ b/nbd.c
@@ -18,6 +18,7 @@
#include "nbd.h"
#include "block.h"
+#include "block_int.h"
#include <errno.h>
#include <string.h>
@@ -186,7 +187,7 @@
Request (type == 2)
*/
-int nbd_negotiate(int csock, off_t size, uint32_t flags)
+static int nbd_send_negotiate(int csock, off_t size, uint32_t flags)
{
char buf[8 + 8 + 8 + 128];
@@ -583,6 +584,33 @@
return 0;
}
+struct NBDExport {
+ BlockDriverState *bs;
+ off_t dev_offset;
+ off_t size;
+ uint8_t *data;
+ uint32_t nbdflags;
+};
+
+NBDExport *nbd_export_new(BlockDriverState *bs, off_t dev_offset,
+ off_t size, uint32_t nbdflags)
+{
+ NBDExport *exp = g_malloc0(sizeof(NBDExport));
+ exp->bs = bs;
+ exp->dev_offset = dev_offset;
+ exp->nbdflags = nbdflags;
+ exp->size = size == -1 ? exp->bs->total_sectors * 512 : size;
+ exp->data = qemu_blockalign(exp->bs, NBD_BUFFER_SIZE);
+ return exp;
+}
+
+void nbd_export_close(NBDExport *exp)
+{
+ qemu_vfree(exp->data);
+ bdrv_close(exp->bs);
+ g_free(exp);
+}
+
static int nbd_do_send_reply(int csock, struct nbd_reply *reply,
uint8_t *data, int len)
{
@@ -652,9 +680,7 @@
return rc;
}
-int nbd_trip(BlockDriverState *bs, int csock, off_t size,
- uint64_t dev_offset, uint32_t nbdflags,
- uint8_t *data)
+int nbd_trip(NBDExport *exp, int csock)
{
struct nbd_request request;
struct nbd_reply reply;
@@ -662,7 +688,7 @@
TRACE("Reading request.");
- ret = nbd_do_receive_request(csock, &request, data);
+ ret = nbd_do_receive_request(csock, &request, exp->data);
if (ret == -EIO) {
return -1;
}
@@ -675,10 +701,11 @@
goto error_reply;
}
- if ((request.from + request.len) > size) {
+ if ((request.from + request.len) > exp->size) {
LOG("From: %" PRIu64 ", Len: %u, Size: %" PRIu64
", Offset: %" PRIu64 "\n",
- request.from, request.len, (uint64_t)size, dev_offset);
+ request.from, request.len,
+ (uint64_t)exp->size, exp->dev_offset);
LOG("requested operation past EOF--bad client?");
goto invalid_request;
}
@@ -687,8 +714,8 @@
case NBD_CMD_READ:
TRACE("Request type is READ");
- ret = bdrv_read(bs, (request.from + dev_offset) / 512,
- data, request.len / 512);
+ ret = bdrv_read(exp->bs, (request.from + exp->dev_offset) / 512,
+ exp->data, request.len / 512);
if (ret < 0) {
LOG("reading from file failed");
reply.error = -ret;
@@ -696,13 +723,13 @@
}
TRACE("Read %u byte(s)", request.len);
- if (nbd_do_send_reply(csock, &reply, data, request.len) < 0)
+ if (nbd_do_send_reply(csock, &reply, exp->data, request.len) < 0)
return -1;
break;
case NBD_CMD_WRITE:
TRACE("Request type is WRITE");
- if (nbdflags & NBD_FLAG_READ_ONLY) {
+ if (exp->nbdflags & NBD_FLAG_READ_ONLY) {
TRACE("Server is read-only, return error");
reply.error = EROFS;
goto error_reply;
@@ -710,8 +737,8 @@
TRACE("Writing to device");
- ret = bdrv_write(bs, (request.from + dev_offset) / 512,
- data, request.len / 512);
+ ret = bdrv_write(exp->bs, (request.from + exp->dev_offset) / 512,
+ exp->data, request.len / 512);
if (ret < 0) {
LOG("writing to file failed");
reply.error = -ret;
@@ -719,7 +746,7 @@
}
if (request.type & NBD_CMD_FLAG_FUA) {
- ret = bdrv_flush(bs);
+ ret = bdrv_flush(exp->bs);
if (ret < 0) {
LOG("flush failed");
reply.error = -ret;
@@ -737,7 +764,7 @@
case NBD_CMD_FLUSH:
TRACE("Request type is FLUSH");
- ret = bdrv_flush(bs);
+ ret = bdrv_flush(exp->bs);
if (ret < 0) {
LOG("flush failed");
reply.error = -ret;
@@ -748,7 +775,7 @@
break;
case NBD_CMD_TRIM:
TRACE("Request type is TRIM");
- ret = bdrv_discard(bs, (request.from + dev_offset) / 512,
+ ret = bdrv_discard(exp->bs, (request.from + exp->dev_offset) / 512,
request.len / 512);
if (ret < 0) {
LOG("discard failed");
@@ -771,3 +798,8 @@
return 0;
}
+
+int nbd_negotiate(NBDExport *exp, int csock)
+{
+ return nbd_send_negotiate(csock, exp->size, exp->nbdflags);
+}
