mirror of
https://github.com/projectacrn/acrn-hypervisor.git
synced 2025-05-03 22:17:03 +00:00
Current IO emulation is synchronous. The user VM need to wait for the completion of the the I/O request before return. But Virtio Spec introduces introduces asynchronous IO with a new register in MMIO/PIO space named NOTIFY, to be used for FE driver to notify BE driver, ACRN hypervisor can emulate this register by sending a notification to vCPU in Service VM side. This way, FE side can resume to work without waiting for the full completion of BE side response. Tracked-On: #8209 Signed-off-by: Conghui <conghui.chen@intel.com> Acked-by: Eddie Dong <eddie.dong@intel.com>
101 lines
2.2 KiB
C
101 lines
2.2 KiB
C
/*
|
|
* SHARED BUFFER
|
|
*
|
|
* Copyright (C) 2017-2022 Intel Corporation.
|
|
*
|
|
* SPDX-License-Identifier: BSD-3-Clause
|
|
*
|
|
* Li Fei <fei1.li@intel.com>
|
|
*
|
|
*/
|
|
|
|
#include <types.h>
|
|
#include <rtl.h>
|
|
#include <errno.h>
|
|
#include <asm/cpu.h>
|
|
#include <asm/per_cpu.h>
|
|
|
|
uint32_t sbuf_next_ptr(uint32_t pos_arg,
|
|
uint32_t span, uint32_t scope)
|
|
{
|
|
uint32_t pos = pos_arg;
|
|
pos += span;
|
|
pos = (pos >= scope) ? (pos - scope) : pos;
|
|
return pos;
|
|
}
|
|
|
|
/**
|
|
* The high caller should guarantee each time there must have
|
|
* sbuf->ele_size data can be write form data and this function
|
|
* should guarantee execution atomically.
|
|
*
|
|
* flag:
|
|
* If OVERWRITE_EN set, buf can store (ele_num - 1) elements at most.
|
|
* Should use lock to guarantee that only one read or write at
|
|
* the same time.
|
|
* if OVERWRITE_EN not set, buf can store (ele_num - 1) elements
|
|
* at most. Shouldn't modify the sbuf->head.
|
|
*
|
|
* return:
|
|
* ele_size: write succeeded.
|
|
* 0: no write, buf is full
|
|
* negative: failed.
|
|
*/
|
|
|
|
uint32_t sbuf_put(struct shared_buf *sbuf, uint8_t *data)
|
|
{
|
|
void *to;
|
|
uint32_t next_tail;
|
|
uint32_t ele_size;
|
|
bool trigger_overwrite = false;
|
|
|
|
stac();
|
|
next_tail = sbuf_next_ptr(sbuf->tail, sbuf->ele_size, sbuf->size);
|
|
|
|
if ((next_tail == sbuf->head) && ((sbuf->flags & OVERWRITE_EN) == 0U)) {
|
|
/* if overrun is not enabled, return 0 directly */
|
|
ele_size = 0U;
|
|
} else {
|
|
if (next_tail == sbuf->head) {
|
|
/* accumulate overrun count if necessary */
|
|
sbuf->overrun_cnt += sbuf->flags & OVERRUN_CNT_EN;
|
|
trigger_overwrite = true;
|
|
}
|
|
to = (void *)sbuf + SBUF_HEAD_SIZE + sbuf->tail;
|
|
|
|
(void)memcpy_s(to, sbuf->ele_size, data, sbuf->ele_size);
|
|
|
|
if (trigger_overwrite) {
|
|
sbuf->head = sbuf_next_ptr(sbuf->head,
|
|
sbuf->ele_size, sbuf->size);
|
|
}
|
|
sbuf->tail = next_tail;
|
|
ele_size = sbuf->ele_size;
|
|
}
|
|
clac();
|
|
|
|
return ele_size;
|
|
}
|
|
|
|
int32_t sbuf_setup_common(struct acrn_vm *vm, uint16_t cpu_id, uint32_t sbuf_id, uint64_t *hva)
|
|
{
|
|
int32_t ret = 0;
|
|
|
|
switch (sbuf_id) {
|
|
case ACRN_TRACE:
|
|
case ACRN_HVLOG:
|
|
case ACRN_SEP:
|
|
case ACRN_SOCWATCH:
|
|
ret = sbuf_share_setup(cpu_id, sbuf_id, hva);
|
|
break;
|
|
case ACRN_ASYNCIO:
|
|
ret = init_asyncio(vm, hva);
|
|
break;
|
|
default:
|
|
pr_err("%s not support sbuf_id %d", __func__, sbuf_id);
|
|
ret = -1;
|
|
}
|
|
|
|
return ret;
|
|
}
|