/*
* Copyright (C) 2018 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "VirtioGpuStream.h"
#include <cros_gralloc_handle.h>
#include <drm/virtgpu_drm.h>
#include <xf86drm.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <errno.h>
#include <unistd.h>
#ifndef PAGE_SIZE
#define PAGE_SIZE 0x1000
#endif
// In a virtual machine, there should only be one GPU
#define RENDERNODE_MINOR 128
// Maximum size of readback / response buffer in bytes
#define MAX_CMDRESPBUF_SIZE (10*PAGE_SIZE)
// Attributes use to allocate our response buffer
// Similar to virgl's fence objects
#define PIPE_BUFFER 0
#define VIRGL_FORMAT_R8_UNORM 64
#define VIRGL_BIND_CUSTOM (1 << 17)
// Conservative; see virgl_winsys.h
#define VIRGL_MAX_CMDBUF_DWORDS (16*1024)
#define VIRGL_MAX_CMDBUF_SIZE (4*VIRGL_MAX_CMDBUF_DWORDS)
struct VirtioGpuCmd {
uint32_t op;
uint32_t cmdSize;
unsigned char buf[0];
} __attribute__((packed));
uint32_t CrosGralloc::getHostHandle(native_handle_t const* handle_)
{
uint32_t id = 0;
if (m_fd >= 0) {
cros_gralloc_handle const* handle =
reinterpret_cast<cros_gralloc_handle const*>(handle_);
drmPrimeFDToHandle(m_fd, handle->fds[0], &id);
}
return id;
}
int CrosGralloc::getFormat(native_handle_t const* handle)
{
return ((cros_gralloc_handle *)handle)->droid_format;
}
bool VirtioGpuProcessPipe::processPipeInit(renderControl_encoder_context_t *rcEnc)
{
union {
uint64_t proto;
struct {
int pid;
int tid;
} id;
} puid = {
.id.pid = getpid(),
.id.tid = gettid(),
};
rcEnc->rcSetPuid(rcEnc, puid.proto);
return true;
}
VirtioGpuStream::VirtioGpuStream(size_t bufSize) :
IOStream(0U),
m_fd(-1),
m_bufSize(bufSize),
m_buf(nullptr),
m_cmdResp_rh(0U),
m_cmdResp_bo(0U),
m_cmdResp(nullptr),
m_cmdRespPos(0U),
m_cmdPos(0U),
m_flushPos(0U),
m_allocSize(0U),
m_allocFlushSize(0U)
{
}
VirtioGpuStream::~VirtioGpuStream()
{
if (m_cmdResp) {
munmap(m_cmdResp, MAX_CMDRESPBUF_SIZE);
}
if (m_cmdResp_bo > 0U) {
drm_gem_close gem_close = {
.handle = m_cmdResp_bo,
};
drmIoctl(m_fd, DRM_IOCTL_GEM_CLOSE, &gem_close);
}
if (m_fd >= 0) {
close(m_fd);
}
free(m_buf);
}
int VirtioGpuStream::connect()
{
if (m_fd < 0) {
m_fd = drmOpenRender(RENDERNODE_MINOR);
if (m_fd < 0) {
ERR("%s: failed with fd %d (%s)", __func__, m_fd, strerror(errno));
return -1;
}
}
if (!m_cmdResp_bo) {
drm_virtgpu_resource_create create = {
.target = PIPE_BUFFER,
.format = VIRGL_FORMAT_R8_UNORM,
.bind = VIRGL_BIND_CUSTOM,
.width = MAX_CMDRESPBUF_SIZE,
.height = 1U,
.depth = 1U,
.array_size = 0U,
.size = MAX_CMDRESPBUF_SIZE,
.stride = MAX_CMDRESPBUF_SIZE,
};
int ret = drmIoctl(m_fd, DRM_IOCTL_VIRTGPU_RESOURCE_CREATE, &create);
if (ret) {
ERR("%s: failed with %d allocating command response buffer (%s)",
__func__, ret, strerror(errno));
return -1;
}
m_cmdResp_bo = create.bo_handle;
if (!m_cmdResp_bo) {
ERR("%s: no handle when allocating command response buffer",
__func__);
return -1;
}
m_cmdResp_rh = create.res_handle;
if (create.size != MAX_CMDRESPBUF_SIZE) {
ERR("%s: command response buffer wrongly sized, create.size=%zu "
"!= %zu", __func__,
static_cast<size_t>(create.size),
static_cast<size_t>(MAX_CMDRESPBUF_SIZE));
abort();
}
}
if (!m_cmdResp) {
drm_virtgpu_map map = {
.handle = m_cmdResp_bo,
};
int ret = drmIoctl(m_fd, DRM_IOCTL_VIRTGPU_MAP, &map);
if (ret) {
ERR("%s: failed with %d mapping command response buffer (%s)",
__func__, ret, strerror(errno));
return -1;
}
m_cmdResp = static_cast<VirtioGpuCmd *>(mmap64(nullptr,
MAX_CMDRESPBUF_SIZE,
PROT_READ, MAP_SHARED,
m_fd, map.offset));
if (m_cmdResp == MAP_FAILED) {
ERR("%s: failed with %d mmap'ing command response buffer (%s)",
__func__, ret, strerror(errno));
return -1;
}
}
m_gralloc.setFd(m_fd);
return 0;
}
int VirtioGpuStream::flush()
{
int ret = commitBuffer(m_allocSize - m_allocFlushSize);
if (ret)
return ret;
m_allocFlushSize = m_allocSize;
return 0;
}
void *VirtioGpuStream::allocBuffer(size_t minSize)
{
if (m_buf) {
// Try to model the alloc() calls being made by the user. They should be
// obeying the protocol and using alloc() for anything they don't write
// with writeFully(), so we can know if this alloc() is for part of a
// command, or not. If it is not for part of a command, we are starting
// a new command, and should increment m_cmdPos.
VirtioGpuCmd *cmd = reinterpret_cast<VirtioGpuCmd *>(&m_buf[m_cmdPos]);
if (m_allocSize + minSize > cmd->cmdSize) {
m_allocFlushSize = 0U;
m_allocSize = 0U;
// This might also be a convenient point to flush commands
if (m_cmdPos + cmd->cmdSize + minSize > m_bufSize) {
if (commitAll() < 0) {
ERR("%s: command flush failed", __func__);
m_flushPos = 0U;
m_bufSize = 0U;
m_cmdPos = 0U;
free(m_buf);
m_buf = nullptr;
return nullptr;
}
} else {
m_cmdPos += cmd->cmdSize;
m_flushPos = m_cmdPos;
}
}
}
// Update m_allocSize here, before minSize is tampered with below
m_allocSize += minSize;
// Make sure anything we already have written to the buffer is retained
minSize += m_flushPos;
size_t allocSize = (m_bufSize < minSize ? minSize : m_bufSize);
if (!m_buf) {
m_buf = static_cast<unsigned char *>(malloc(allocSize));
} else if (m_bufSize < allocSize) {
unsigned char *p = static_cast<unsigned char *>(realloc(m_buf, allocSize));
if (!p) {
free(m_buf);
}
m_buf = p;
}
if (!m_buf) {
ERR("%s: alloc (%zu) failed\n", __func__, allocSize);
m_allocFlushSize = 0U;
m_allocSize = 0U;
m_flushPos = 0U;
m_bufSize = 0U;
m_cmdPos = 0U;
} else {
m_bufSize = allocSize;
}
if (m_flushPos == 0 && m_cmdPos == 0) {
// During initialization, HostConnection will send an empty command
// packet to check the connection is good, but it doesn't obey the usual
// line protocol. This is a 4 byte write to [0], which is our 'op' field,
// and we don't have an op=0 so it's OK. We fake up a valid length, and
// overload this workaround by putting the res_handle for the readback
// buffer in the command payload, patched in just before we submit.
VirtioGpuCmd *cmd = reinterpret_cast<VirtioGpuCmd *>(&m_buf[m_cmdPos]);
cmd->op = 0U;
cmd->cmdSize = sizeof(*cmd) + sizeof(__u32);
}
return m_buf + m_cmdPos;
}
// For us, writeFully() means to write a command without any header, directly
// into the buffer stream. We can use the packet frame written directly to the
// stream to verify this write is within bounds, then update the counter.
int VirtioGpuStream::writeFully(const void *buf, size_t len)
{
if (!valid())
return -1;
if (!buf) {
if (len > 0) {
// If len is non-zero, buf must not be NULL. Otherwise the pipe would
// be in a corrupted state, which is lethal for the emulator.
ERR("%s: failed, buf=NULL, len %zu, lethal error, exiting",
__func__, len);
abort();
}
return 0;
}
VirtioGpuCmd *cmd = reinterpret_cast<VirtioGpuCmd *>(&m_buf[m_cmdPos]);
if (m_flushPos < sizeof(*cmd)) {
ERR("%s: writeFully len %zu would overwrite command header, "
"cmd_pos=%zu, flush_pos=%zu, lethal error, exiting", __func__,
len, m_cmdPos, m_flushPos);
abort();
}
if (m_flushPos + len > cmd->cmdSize) {
ERR("%s: writeFully len %zu would overflow the command bounds, "
"cmd_pos=%zu, flush_pos=%zu, cmdsize=%zu, lethal error, exiting",
__func__, len, m_cmdPos, m_flushPos, cmd->cmdSize);
abort();
}
if (len > VIRGL_MAX_CMDBUF_SIZE) {
ERR("%s: Large command (%zu bytes) exceeds virgl limits",
__func__, len);
/* Fall through */
}
memcpy(&m_buf[m_flushPos], buf, len);
commitBuffer(len);
m_allocSize += len;
return 0;
}
const unsigned char *VirtioGpuStream::readFully(void *buf, size_t len)
{
if (!valid())
return nullptr;
if (!buf) {
if (len > 0) {
// If len is non-zero, buf must not be NULL. Otherwise the pipe would
// be in a corrupted state, which is lethal for the emulator.
ERR("%s: failed, buf=NULL, len %zu, lethal error, exiting.",
__func__, len);
abort();
}
return nullptr;
}
// Read is too big for current architecture
if (len > MAX_CMDRESPBUF_SIZE - sizeof(*m_cmdResp)) {
ERR("%s: failed, read too large, len %zu, lethal error, exiting.",
__func__, len);
abort();
}
// Commit all outstanding write commands (if any)
if (commitAll() < 0) {
ERR("%s: command flush failed", __func__);
return nullptr;
}
if (len > 0U && m_cmdRespPos == 0U) {
// When we are about to read for the first time, wait for the virtqueue
// to drain to this command, otherwise the data could be stale
drm_virtgpu_3d_wait wait = {
.handle = m_cmdResp_bo,
};
int ret = drmIoctl(m_fd, DRM_IOCTL_VIRTGPU_WAIT, &wait);
if (ret) {
ERR("%s: failed with %d waiting for response buffer (%s)",
__func__, ret, strerror(errno));
// Fall through, hope for the best
}
}
// Most likely a protocol implementation error
if (m_cmdResp->cmdSize - sizeof(*m_cmdResp) < m_cmdRespPos + len) {
ERR("%s: failed, op %zu, len %zu, cmdSize %zu, pos %zu, lethal "
"error, exiting.", __func__, m_cmdResp->op, len,
m_cmdResp->cmdSize, m_cmdRespPos);
abort();
}
memcpy(buf, &m_cmdResp->buf[m_cmdRespPos], len);
if (m_cmdRespPos + len == m_cmdResp->cmdSize - sizeof(*m_cmdResp)) {
m_cmdRespPos = 0U;
} else {
m_cmdRespPos += len;
}
return reinterpret_cast<const unsigned char *>(buf);
}
int VirtioGpuStream::commitBuffer(size_t size)
{
if (m_flushPos + size > m_bufSize) {
ERR("%s: illegal commit size %zu, flushPos %zu, bufSize %zu",
__func__, size, m_flushPos, m_bufSize);
return -1;
}
m_flushPos += size;
return 0;
}
int VirtioGpuStream::commitAll()
{
size_t pos = 0U, numFlushed = 0U;
while (pos < m_flushPos) {
VirtioGpuCmd *cmd = reinterpret_cast<VirtioGpuCmd *>(&m_buf[pos]);
// Should never happen
if (pos + cmd->cmdSize > m_bufSize) {
ERR("%s: failed, pos %zu, cmdSize %zu, bufSize %zu, lethal "
"error, exiting.", __func__, pos, cmd->cmdSize, m_bufSize);
abort();
}
// Saw dummy command; patch it with res handle
if (cmd->op == 0) {
*(uint32_t *)cmd->buf = m_cmdResp_rh;
}
// Flush a single command
drm_virtgpu_execbuffer execbuffer = {
.size = cmd->cmdSize,
.command = reinterpret_cast<__u64>(cmd),
.bo_handles = reinterpret_cast<__u64>(&m_cmdResp_bo),
.num_bo_handles = 1U,
};
int ret = drmIoctl(m_fd, DRM_IOCTL_VIRTGPU_EXECBUFFER, &execbuffer);
if (ret) {
ERR("%s: failed with %d executing command buffer (%s)", __func__,
ret, strerror(errno));
return -1;
}
pos += cmd->cmdSize;
numFlushed++;
}
if (pos > m_flushPos) {
ERR("%s: aliasing, flushPos %zu, pos %zu, probably ok", __func__,
m_flushPos, pos);
/* Fall through */
}
m_flushPos = 0U;
m_cmdPos = 0U;
return 0;
}