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/*
* reqlist API
*
* Copyright (C) 2013 Proxmox Server Solutions
* Copyright (c) 2021 Virtuozzo International GmbH.
*
* Authors:
* Dietmar Maurer (dietmar@proxmox.com)
* Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "qemu/range.h"
#include "block/reqlist.h"
void reqlist_init_req(BlockReqList *reqs, BlockReq *req, int64_t offset,
int64_t bytes)
{
assert(!reqlist_find_conflict(reqs, offset, bytes));
*req = (BlockReq) {
.offset = offset,
.bytes = bytes,
};
qemu_co_queue_init(&req->wait_queue);
QLIST_INSERT_HEAD(reqs, req, list);
}
BlockReq *reqlist_find_conflict(BlockReqList *reqs, int64_t offset,
int64_t bytes)
{
BlockReq *r;
QLIST_FOREACH(r, reqs, list) {
if (ranges_overlap(offset, bytes, r->offset, r->bytes)) {
return r;
}
}
return NULL;
}
bool coroutine_fn reqlist_wait_one(BlockReqList *reqs, int64_t offset,
int64_t bytes, CoMutex *lock)
{
BlockReq *r = reqlist_find_conflict(reqs, offset, bytes);
if (!r) {
return false;
}
qemu_co_queue_wait(&r->wait_queue, lock);
return true;
}
void coroutine_fn reqlist_wait_all(BlockReqList *reqs, int64_t offset,
int64_t bytes, CoMutex *lock)
{
while (reqlist_wait_one(reqs, offset, bytes, lock)) {
/* continue */
}
}
void coroutine_fn reqlist_shrink_req(BlockReq *req, int64_t new_bytes)
{
if (new_bytes == req->bytes) {
return;
}
assert(new_bytes > 0 && new_bytes < req->bytes);
req->bytes = new_bytes;
qemu_co_queue_restart_all(&req->wait_queue);
}
void coroutine_fn reqlist_remove_req(BlockReq *req)
{
QLIST_REMOVE(req, list);
qemu_co_queue_restart_all(&req->wait_queue);
}
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