5:17 p.m.
Support sending 64-bit requests if extended headers were negotiated.
At this point, h->extended_headers is permanently false (we can't
enable it until all other aspects of the protocol have likewise been
converted).
---
lib/internal.h | 12 ++++++++---
generator/states-issue-command.c | 31 +++++++++++++++++++----------
generator/states-reply-structured.c | 2 +-
lib/rw.c | 10 ++++------
4 files changed, 34 insertions(+), 21 deletions(-)
diff --git a/lib/internal.h b/lib/internal.h
index 7e96e8e9..07378588 100644
--- a/lib/internal.h
+++ b/lib/internal.h
@@ -1,5 +1,5 @@
/* nbd client library in userspace: internal definitions
- * Copyright (C) 2013-2020 Red Hat Inc.
+ * Copyright (C) 2013-2021 Red Hat Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
@@ -106,6 +106,9 @@ struct nbd_handle {
char *tls_username; /* Username, NULL = use current username */
char *tls_psk_file; /* PSK filename, NULL = no PSK */
+ /* Extended headers. */
+ bool extended_headers; /* If we negotiated NBD_OPT_EXTENDED_HEADERS */
+
/* Desired metadata contexts. */
bool request_sr;
string_vector request_meta_contexts;
@@ -242,7 +245,10 @@ struct nbd_handle {
/* Issuing a command must use a buffer separate from sbuf, for the
* case when we interrupt a request to service a reply.
*/
- struct nbd_request request;
+ union {
+ struct nbd_request request;
+ struct nbd_request_ext request_ext;
+ } req;
bool in_write_payload;
bool in_write_shutdown;
@@ -347,7 +353,7 @@ struct command {
uint16_t type;
uint64_t cookie;
uint64_t offset;
- uint32_t count;
+ uint64_t count;
void *data; /* Buffer for read/write */
struct command_cb cb;
enum state state; /* State to resume with on next POLLIN */
diff --git a/generator/states-issue-command.c b/generator/states-issue-command.c
index a8101144..7b1d6dc7 100644
--- a/generator/states-issue-command.c
+++ b/generator/states-issue-command.c
@@ -1,5 +1,5 @@
/* nbd client library in userspace: state machine
- * Copyright (C) 2013-2020 Red Hat Inc.
+ * Copyright (C) 2013-2021 Red Hat Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
@@ -41,14 +41,23 @@ STATE_MACHINE {
return 0;
}
- h->request.magic = htobe32 (NBD_REQUEST_MAGIC);
- h->request.flags = htobe16 (cmd->flags);
- h->request.type = htobe16 (cmd->type);
- h->request.handle = htobe64 (cmd->cookie);
- h->request.offset = htobe64 (cmd->offset);
- h->request.count = htobe32 ((uint32_t) cmd->count);
- h->wbuf = &h->request;
- h->wlen = sizeof (h->request);
+ /* These fields are coincident between req.request and req.request_ext */
+ h->req.request.flags = htobe16 (cmd->flags);
+ h->req.request.type = htobe16 (cmd->type);
+ h->req.request.handle = htobe64 (cmd->cookie);
+ h->req.request.offset = htobe64 (cmd->offset);
+ if (h->extended_headers) {
+ h->req.request_ext.magic = htobe32 (NBD_REQUEST_EXT_MAGIC);
+ h->req.request_ext.count = htobe64 (cmd->count);
+ h->wlen = sizeof (h->req.request_ext);
+ }
+ else {
+ assert (cmd->count <= UINT32_MAX);
+ h->req.request.magic = htobe32 (NBD_REQUEST_MAGIC);
+ h->req.request.count = htobe32 (cmd->count);
+ h->wlen = sizeof (h->req.request);
+ }
+ h->wbuf = &h->req;
if (cmd->type == NBD_CMD_WRITE || cmd->next)
h->wflags = MSG_MORE;
SET_NEXT_STATE (%SEND_REQUEST);
@@ -73,7 +82,7 @@ STATE_MACHINE {
assert (h->cmds_to_issue != NULL);
cmd = h->cmds_to_issue;
- assert (cmd->cookie == be64toh (h->request.handle));
+ assert (cmd->cookie == be64toh (h->req.request.handle));
if (cmd->type == NBD_CMD_WRITE) {
h->wbuf = cmd->data;
h->wlen = cmd->count;
@@ -119,7 +128,7 @@ STATE_MACHINE {
assert (!h->wlen);
assert (h->cmds_to_issue != NULL);
cmd = h->cmds_to_issue;
- assert (cmd->cookie == be64toh (h->request.handle));
+ assert (cmd->cookie == be64toh (h->req.request.handle));
h->cmds_to_issue = cmd->next;
if (h->cmds_to_issue_tail == cmd)
h->cmds_to_issue_tail = NULL;
diff --git a/generator/states-reply-structured.c b/generator/states-reply-structured.c
index e1da850d..5524e000 100644
--- a/generator/states-reply-structured.c
+++ b/generator/states-reply-structured.c
@@ -34,7 +34,7 @@ structured_reply_in_bounds (uint64_t offset, uint32_t length,
offset + length > cmd->offset + cmd->count) {
set_error (0, "range of structured reply is out of bounds, "
"offset=%" PRIu64 ", cmd->offset=%" PRIu64 ",
"
- "length=%" PRIu32 ", cmd->count=%" PRIu32 ":
"
+ "length=%" PRIu32 ", cmd->count=%" PRIu64 ":
"
"this is likely to be a bug in the NBD server",
offset, cmd->offset, length, cmd->count);
return false;
diff --git a/lib/rw.c b/lib/rw.c
index 4ade7508..16c2e848 100644
--- a/lib/rw.c
+++ b/lib/rw.c
@@ -1,5 +1,5 @@
/* NBD client library in userspace
- * Copyright (C) 2013-2020 Red Hat Inc.
+ * Copyright (C) 2013-2021 Red Hat Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
@@ -216,13 +216,11 @@ nbd_internal_command_common (struct nbd_handle *h,
}
break;
- /* Other commands are currently limited by the 32 bit field in the
- * command structure on the wire, but in future we hope to support
- * 64 bit values here with a change to the NBD protocol which is
- * being discussed upstream.
+ /* Other commands are limited by the 32 bit field in the command
+ * structure on the wire, unless extended headers were negotiated.
*/
default:
- if (count > UINT32_MAX) {
+ if (!h->extended_headers && count > UINT32_MAX) {
set_error (ERANGE, "request too large: maximum request size is %"
PRIu32,
UINT32_MAX);
goto err;
--
2.33.1