From: Eric Blake <eblake@redhat.com>
To: qemu-devel@nongnu.org
Cc: kwolf@redhat.com, pkrempa@redhat.com, qemu-block@nongnu.org,
armbru@redhat.com, rjones@redhat.com, vsementsov@virtuozzo.com,
stefanha@redhat.com
Subject: [PATCH v6 06/11] nbd: Refactor counting of metadata contexts
Date: Tue, 27 Oct 2020 00:05:51 -0500 [thread overview]
Message-ID: <20201027050556.269064-7-eblake@redhat.com> (raw)
In-Reply-To: <20201027050556.269064-1-eblake@redhat.com>
Rather than open-code the count of negotiated contexts at several
sites, embed it directly into the struct. This will make it easier
for upcoming commits to support even more simultaneous contexts.
Signed-off-by: Eric Blake <eblake@redhat.com>
---
nbd/server.c | 26 +++++++++++++++-----------
1 file changed, 15 insertions(+), 11 deletions(-)
diff --git a/nbd/server.c b/nbd/server.c
index 77fdecdf9dec..42d494bc9616 100644
--- a/nbd/server.c
+++ b/nbd/server.c
@@ -104,8 +104,7 @@ static QTAILQ_HEAD(, NBDExport) exports = QTAILQ_HEAD_INITIALIZER(exports);
* NBD_OPT_LIST_META_CONTEXT. */
typedef struct NBDExportMetaContexts {
NBDExport *exp;
- bool valid; /* means that negotiation of the option finished without
- errors */
+ size_t count; /* number of negotiated contexts */
bool base_allocation; /* export base:allocation context (block status) */
bool bitmap; /* export qemu:dirty-bitmap:<export bitmap name> */
} NBDExportMetaContexts;
@@ -445,7 +444,9 @@ static int nbd_negotiate_handle_list(NBDClient *client, Error **errp)
static void nbd_check_meta_export(NBDClient *client)
{
- client->export_meta.valid &= client->exp == client->export_meta.exp;
+ if (client->exp != client->export_meta.exp) {
+ client->export_meta.count = 0;
+ }
}
/* Send a reply to NBD_OPT_EXPORT_NAME.
@@ -945,6 +946,7 @@ static int nbd_negotiate_meta_queries(NBDClient *client,
NBDExportMetaContexts local_meta;
uint32_t nb_queries;
int i;
+ size_t count = 0;
if (!client->structured_reply) {
return nbd_opt_invalid(client, errp,
@@ -1001,6 +1003,7 @@ static int nbd_negotiate_meta_queries(NBDClient *client,
if (ret < 0) {
return ret;
}
+ count++;
}
if (meta->bitmap) {
@@ -1014,11 +1017,12 @@ static int nbd_negotiate_meta_queries(NBDClient *client,
if (ret < 0) {
return ret;
}
+ count++;
}
ret = nbd_negotiate_send_rep(client, NBD_REP_ACK, errp);
if (ret == 0) {
- meta->valid = true;
+ meta->count = count;
}
return ret;
@@ -2337,18 +2341,16 @@ static coroutine_fn int nbd_handle_request(NBDClient *client,
return nbd_send_generic_reply(client, request->handle, -EINVAL,
"need non-zero length", errp);
}
- if (client->export_meta.valid &&
- (client->export_meta.base_allocation ||
- client->export_meta.bitmap))
- {
+ if (client->export_meta.count) {
bool dont_fragment = request->flags & NBD_CMD_FLAG_REQ_ONE;
+ int contexts_remaining = client->export_meta.count;
if (client->export_meta.base_allocation) {
ret = nbd_co_send_block_status(client, request->handle,
blk_bs(exp->common.blk),
request->from,
request->len, dont_fragment,
- !client->export_meta.bitmap,
+ !--contexts_remaining,
NBD_META_ID_BASE_ALLOCATION,
errp);
if (ret < 0) {
@@ -2360,13 +2362,15 @@ static coroutine_fn int nbd_handle_request(NBDClient *client,
ret = nbd_co_send_bitmap(client, request->handle,
client->exp->export_bitmap,
request->from, request->len,
- dont_fragment,
- true, NBD_META_ID_DIRTY_BITMAP, errp);
+ dont_fragment, !--contexts_remaining,
+ NBD_META_ID_DIRTY_BITMAP, errp);
if (ret < 0) {
return ret;
}
}
+ assert(!contexts_remaining);
+
return 0;
} else {
return nbd_send_generic_reply(client, request->handle, -EINVAL,
--
2.29.0
next prev parent reply other threads:[~2020-10-27 5:09 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-27 5:05 [PATCH v6 00/11] Exposing backing-chain allocation over NBD Eric Blake
2020-10-27 5:05 ` [PATCH v6 01/11] block: Simplify QAPI_LIST_ADD Eric Blake
2020-10-27 10:06 ` Vladimir Sementsov-Ogievskiy
2020-10-27 12:58 ` Markus Armbruster
2020-10-27 5:05 ` [PATCH v6 02/11] qapi: Make QAPI_LIST_ADD() public Eric Blake
2020-10-27 5:05 ` [PATCH v6 03/11] nbd: Utilize QAPI_CLONE for type conversion Eric Blake
2020-10-27 5:05 ` [PATCH v6 04/11] nbd: Update qapi to support exporting multiple bitmaps Eric Blake
2020-10-27 10:29 ` Vladimir Sementsov-Ogievskiy
2020-10-27 12:37 ` Peter Krempa
2020-10-27 5:05 ` [PATCH v6 05/11] nbd: Simplify qemu bitmap context name Eric Blake
2020-10-27 5:05 ` Eric Blake [this message]
2020-10-27 10:33 ` [PATCH v6 06/11] nbd: Refactor counting of metadata contexts Vladimir Sementsov-Ogievskiy
2020-10-27 5:05 ` [PATCH v6 07/11] nbd: Allow export of multiple bitmaps for one device Eric Blake
2020-10-27 5:05 ` [PATCH v6 08/11] block: Return depth level during bdrv_is_allocated_above Eric Blake
2020-10-27 12:05 ` Vladimir Sementsov-Ogievskiy
2020-10-27 5:05 ` [PATCH v6 09/11] nbd: Add new qemu:allocation-depth metadata context Eric Blake
2020-10-27 10:53 ` Vladimir Sementsov-Ogievskiy
2020-10-27 5:05 ` [PATCH v6 10/11] nbd: Add 'qemu-nbd -A' to expose allocation depth Eric Blake
2020-10-27 11:03 ` Vladimir Sementsov-Ogievskiy
2020-10-27 5:05 ` [PATCH v6 11/11] qapi: Use QAPI_LIST_ADD() where possible Eric Blake
2020-10-27 5:53 ` Thomas Huth
2020-10-27 6:39 ` David Gibson
2020-10-27 10:09 ` Markus Armbruster
2020-10-27 12:28 ` Eric Blake
2020-10-27 15:36 ` Markus Armbruster
2020-10-27 18:44 ` Eric Blake
2020-10-27 11:26 ` Dr. David Alan Gilbert
2020-10-27 13:42 ` Vladimir Sementsov-Ogievskiy
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