aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--block/nbd-client.c9
-rw-r--r--include/block/nbd.h18
-rw-r--r--nbd/client.c9
-rw-r--r--nbd/nbd-internal.h4
-rw-r--r--nbd/server.c39
5 files changed, 42 insertions, 37 deletions
diff --git a/block/nbd-client.c b/block/nbd-client.c
index 40b28ab00b..8ca503015c 100644
--- a/block/nbd-client.c
+++ b/block/nbd-client.c
@@ -1,6 +1,7 @@
/*
* QEMU Block driver for NBD
*
+ * Copyright (C) 2016 Red Hat, Inc.
* Copyright (C) 2008 Bull S.A.S.
* Author: Laurent Vivier <Laurent.Vivier@bull.net>
*
@@ -258,7 +259,7 @@ int nbd_client_co_pwritev(BlockDriverState *bs, uint64_t offset,
if (flags & BDRV_REQ_FUA) {
assert(client->nbdflags & NBD_FLAG_SEND_FUA);
- request.type |= NBD_CMD_FLAG_FUA;
+ request.flags |= NBD_CMD_FLAG_FUA;
}
assert(bytes <= NBD_MAX_BUFFER_SIZE);
@@ -343,11 +344,7 @@ void nbd_client_attach_aio_context(BlockDriverState *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
- };
+ struct nbd_request request = { .type = NBD_CMD_DISC };
if (client->ioc == NULL) {
return;
diff --git a/include/block/nbd.h b/include/block/nbd.h
index fd58390d5d..5fe2670fdb 100644
--- a/include/block/nbd.h
+++ b/include/block/nbd.h
@@ -1,4 +1,5 @@
/*
+ * Copyright (C) 2016 Red Hat, Inc.
* Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
*
* Network Block Device
@@ -32,7 +33,8 @@ struct nbd_request {
uint64_t handle;
uint64_t from;
uint32_t len;
- uint32_t type;
+ uint16_t flags;
+ uint16_t type;
};
struct nbd_reply {
@@ -40,6 +42,8 @@ struct nbd_reply {
uint32_t error;
};
+/* Transmission (export) flags: sent from server to client during handshake,
+ but describe what will happen during transmission */
#define NBD_FLAG_HAS_FLAGS (1 << 0) /* Flags are there */
#define NBD_FLAG_READ_ONLY (1 << 1) /* Device is read-only */
#define NBD_FLAG_SEND_FLUSH (1 << 2) /* Send FLUSH */
@@ -47,10 +51,12 @@ struct nbd_reply {
#define NBD_FLAG_ROTATIONAL (1 << 4) /* Use elevator algorithm - rotational media */
#define NBD_FLAG_SEND_TRIM (1 << 5) /* Send TRIM (discard) */
-/* New-style global flags. */
+/* New-style handshake (global) flags, sent from server to client, and
+ control what will happen during handshake phase. */
#define NBD_FLAG_FIXED_NEWSTYLE (1 << 0) /* Fixed newstyle protocol. */
-/* New-style client flags. */
+/* New-style client flags, sent from client to server to control what happens
+ during handshake phase. */
#define NBD_FLAG_C_FIXED_NEWSTYLE (1 << 0) /* Fixed newstyle protocol. */
/* Reply types. */
@@ -61,10 +67,10 @@ struct nbd_reply {
#define NBD_REP_ERR_INVALID ((UINT32_C(1) << 31) | 3) /* Invalid length. */
#define NBD_REP_ERR_TLS_REQD ((UINT32_C(1) << 31) | 5) /* TLS required */
+/* Request flags, sent from client to server during transmission phase */
+#define NBD_CMD_FLAG_FUA (1 << 0)
-#define NBD_CMD_MASK_COMMAND 0x0000ffff
-#define NBD_CMD_FLAG_FUA (1 << 16)
-
+/* Supported request types */
enum {
NBD_CMD_READ = 0,
NBD_CMD_WRITE = 1,
diff --git a/nbd/client.c b/nbd/client.c
index f6db8369b3..4620e8dcba 100644
--- a/nbd/client.c
+++ b/nbd/client.c
@@ -1,4 +1,5 @@
/*
+ * Copyright (C) 2016 Red Hat, Inc.
* Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
*
* Network Block Device Client Side
@@ -714,11 +715,13 @@ ssize_t nbd_send_request(QIOChannel *ioc, struct nbd_request *request)
TRACE("Sending request to server: "
"{ .from = %" PRIu64", .len = %" PRIu32 ", .handle = %" PRIu64
- ", .type=%" PRIu32 " }",
- request->from, request->len, request->handle, request->type);
+ ", .flags = %" PRIx16 ", .type = %" PRIu16 " }",
+ request->from, request->len, request->handle,
+ request->flags, request->type);
stl_be_p(buf, NBD_REQUEST_MAGIC);
- stl_be_p(buf + 4, request->type);
+ stw_be_p(buf + 4, request->flags);
+ stw_be_p(buf + 6, request->type);
stq_be_p(buf + 8, request->handle);
stq_be_p(buf + 16, request->from);
stl_be_p(buf + 24, request->len);
diff --git a/nbd/nbd-internal.h b/nbd/nbd-internal.h
index 7e78064021..99e51571a2 100644
--- a/nbd/nbd-internal.h
+++ b/nbd/nbd-internal.h
@@ -53,10 +53,10 @@
/* This is all part of the "official" NBD API.
*
* The most up-to-date documentation is available at:
- * https://github.com/yoe/nbd/blob/master/doc/proto.txt
+ * https://github.com/yoe/nbd/blob/master/doc/proto.md
*/
-#define NBD_REQUEST_SIZE (4 + 4 + 8 + 8 + 4)
+#define NBD_REQUEST_SIZE (4 + 2 + 2 + 8 + 8 + 4)
#define NBD_REPLY_SIZE (4 + 4 + 8)
#define NBD_REQUEST_MAGIC 0x25609513
#define NBD_REPLY_MAGIC 0x67446698
diff --git a/nbd/server.c b/nbd/server.c
index ac42391b45..38a0fef4d9 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -1,4 +1,5 @@
/*
+ * Copyright (C) 2016 Red Hat, Inc.
* Copyright (C) 2005 Anthony Liguori <anthony@codemonkey.ws>
*
* Network Block Device Server Side
@@ -652,21 +653,23 @@ static ssize_t nbd_receive_request(QIOChannel *ioc, struct nbd_request *request)
/* Request
[ 0 .. 3] magic (NBD_REQUEST_MAGIC)
- [ 4 .. 7] type (0 == READ, 1 == WRITE)
+ [ 4 .. 5] flags (NBD_CMD_FLAG_FUA, ...)
+ [ 6 .. 7] type (NBD_CMD_READ, ...)
[ 8 .. 15] handle
[16 .. 23] from
[24 .. 27] len
*/
magic = ldl_be_p(buf);
- request->type = ldl_be_p(buf + 4);
+ request->flags = lduw_be_p(buf + 4);
+ request->type = lduw_be_p(buf + 6);
request->handle = ldq_be_p(buf + 8);
request->from = ldq_be_p(buf + 16);
request->len = ldl_be_p(buf + 24);
- TRACE("Got request: { magic = 0x%" PRIx32 ", .type = %" PRIx32
- ", from = %" PRIu64 " , len = %" PRIu32 " }",
- magic, request->type, request->from, request->len);
+ TRACE("Got request: { magic = 0x%" PRIx32 ", .flags = %" PRIx16
+ ", .type = %" PRIx16 ", from = %" PRIu64 ", len = %" PRIu32 " }",
+ magic, request->flags, request->type, request->from, request->len);
if (magic != NBD_REQUEST_MAGIC) {
LOG("invalid magic (got 0x%" PRIx32 ")", magic);
@@ -1013,7 +1016,6 @@ static ssize_t nbd_co_receive_request(NBDRequest *req,
struct nbd_request *request)
{
NBDClient *client = req->client;
- uint32_t command;
ssize_t rc;
g_assert(qemu_in_coroutine());
@@ -1030,13 +1032,12 @@ static ssize_t nbd_co_receive_request(NBDRequest *req,
TRACE("Decoding type");
- command = request->type & NBD_CMD_MASK_COMMAND;
- if (command != NBD_CMD_WRITE) {
+ if (request->type != NBD_CMD_WRITE) {
/* No payload, we are ready to read the next request. */
req->complete = true;
}
- if (command == NBD_CMD_DISC) {
+ if (request->type == NBD_CMD_DISC) {
/* Special case: we're going to disconnect without a reply,
* whether or not flags, from, or len are bogus */
TRACE("Request type is DISCONNECT");
@@ -1053,7 +1054,7 @@ static ssize_t nbd_co_receive_request(NBDRequest *req,
goto out;
}
- if (command == NBD_CMD_READ || command == NBD_CMD_WRITE) {
+ if (request->type == NBD_CMD_READ || request->type == NBD_CMD_WRITE) {
if (request->len > NBD_MAX_BUFFER_SIZE) {
LOG("len (%" PRIu32" ) is larger than max len (%u)",
request->len, NBD_MAX_BUFFER_SIZE);
@@ -1067,7 +1068,7 @@ static ssize_t nbd_co_receive_request(NBDRequest *req,
goto out;
}
}
- if (command == NBD_CMD_WRITE) {
+ if (request->type == NBD_CMD_WRITE) {
TRACE("Reading %" PRIu32 " byte(s)", request->len);
if (read_sync(client->ioc, req->data, request->len) != request->len) {
@@ -1083,12 +1084,11 @@ static ssize_t nbd_co_receive_request(NBDRequest *req,
LOG("operation past EOF; From: %" PRIu64 ", Len: %" PRIu32
", Size: %" PRIu64, request->from, request->len,
(uint64_t)client->exp->size);
- rc = command == NBD_CMD_WRITE ? -ENOSPC : -EINVAL;
+ rc = request->type == NBD_CMD_WRITE ? -ENOSPC : -EINVAL;
goto out;
}
- if (request->type & ~NBD_CMD_MASK_COMMAND & ~NBD_CMD_FLAG_FUA) {
- LOG("unsupported flags (got 0x%x)",
- request->type & ~NBD_CMD_MASK_COMMAND);
+ if (request->flags & ~NBD_CMD_FLAG_FUA) {
+ LOG("unsupported flags (got 0x%x)", request->flags);
rc = -EINVAL;
goto out;
}
@@ -1110,7 +1110,6 @@ static void nbd_trip(void *opaque)
struct nbd_request request;
struct nbd_reply reply;
ssize_t ret;
- uint32_t command;
int flags;
TRACE("Reading request.");
@@ -1134,7 +1133,6 @@ static void nbd_trip(void *opaque)
reply.error = -ret;
goto error_reply;
}
- command = request.type & NBD_CMD_MASK_COMMAND;
if (client->closing) {
/*
@@ -1144,11 +1142,12 @@ static void nbd_trip(void *opaque)
goto done;
}
- switch (command) {
+ switch (request.type) {
case NBD_CMD_READ:
TRACE("Request type is READ");
- if (request.type & NBD_CMD_FLAG_FUA) {
+ /* XXX: NBD Protocol only documents use of FUA with WRITE */
+ if (request.flags & NBD_CMD_FLAG_FUA) {
ret = blk_co_flush(exp->blk);
if (ret < 0) {
LOG("flush failed");
@@ -1181,7 +1180,7 @@ static void nbd_trip(void *opaque)
TRACE("Writing to device");
flags = 0;
- if (request.type & NBD_CMD_FLAG_FUA) {
+ if (request.flags & NBD_CMD_FLAG_FUA) {
flags |= BDRV_REQ_FUA;
}
ret = blk_pwrite(exp->blk, request.from + exp->dev_offset,