1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140
|
/*
* Copyright (C) 2022 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 <android-base/logging.h>
#include <liburing.h>
#include "liburing/io_uring.h"
#include "usb.h"
static int prep_async_read(struct io_uring* ring, int fd, void* data, size_t len, int64_t offset) {
if (io_uring_sq_space_left(ring) <= 0) {
LOG(ERROR) << "Submission queue run out of space.";
return -1;
}
auto sqe = io_uring_get_sqe(ring);
if (sqe == nullptr) {
return -1;
}
io_uring_sqe_set_flags(sqe, IOSQE_IO_LINK | IOSQE_ASYNC);
io_uring_prep_read(sqe, fd, data, len, offset);
return 0;
}
static int prep_async_write(struct io_uring* ring, int fd, const void* data, size_t len,
int64_t offset) {
if (io_uring_sq_space_left(ring) <= 0) {
LOG(ERROR) << "Submission queue run out of space.";
return -1;
}
auto sqe = io_uring_get_sqe(ring);
if (sqe == nullptr) {
return -1;
}
io_uring_sqe_set_flags(sqe, IOSQE_IO_LINK | IOSQE_ASYNC);
io_uring_prep_write(sqe, fd, data, len, offset);
return 0;
}
template <bool read, typename T>
int prep_async_io(struct io_uring* ring, int fd, T* data, size_t len, int64_t offset) {
if constexpr (read) {
return prep_async_read(ring, fd, data, len, offset);
} else {
return prep_async_write(ring, fd, data, len, offset);
}
}
template <typename T>
static constexpr T DivRoundup(T x, T y) {
return (x + y - 1) / y;
}
extern int getMaxPacketSize(int ffs_fd);
template <bool read, typename T>
static int usb_ffs_do_aio(usb_handle* h, T* const data, const int len) {
const aio_block* aiob = read ? &h->read_aiob : &h->write_aiob;
const int num_requests = DivRoundup<int>(len, h->io_size);
auto cur_data = data;
const auto packet_size = getMaxPacketSize(aiob->fd);
for (int bytes_remain = len; bytes_remain > 0;) {
const int buf_len = std::min(bytes_remain, static_cast<int>(h->io_size));
const auto ret = prep_async_io<read>(&h->ring, aiob->fd, cur_data, buf_len, 0);
if (ret < 0) {
PLOG(ERROR) << "Failed to queue io_uring request";
return -1;
}
bytes_remain -= buf_len;
cur_data = reinterpret_cast<T*>(reinterpret_cast<size_t>(cur_data) + buf_len);
}
const int ret = io_uring_submit(&h->ring);
if (ret <= 0 || ret != num_requests) {
PLOG(ERROR) << "io_uring: failed to submit SQE entries to kernel";
return -1;
}
int res = 0;
bool success = true;
for (int i = 0; i < num_requests; ++i) {
struct io_uring_cqe* cqe{};
const auto ret = TEMP_FAILURE_RETRY(io_uring_wait_cqe(&h->ring, &cqe));
if (ret < 0 || cqe == nullptr) {
PLOG(ERROR) << "Failed to get CQE from kernel";
success = false;
continue;
}
res += cqe->res;
if (cqe->res < 0) {
LOG(ERROR) << "io_uring request failed:, i = " << i
<< ", num_requests = " << num_requests << ", res = " << cqe->res << ": "
<< strerror(cqe->res) << (read ? " read" : " write")
<< " request size: " << len << ", io_size: " << h->io_size
<< " max packet size: " << packet_size << ", fd: " << aiob->fd;
success = false;
errno = -cqe->res;
}
io_uring_cqe_seen(&h->ring, cqe);
}
if (!success) {
return -1;
}
return res;
}
static int usb_ffs_io_uring_read(usb_handle* h, void* data, int len, bool /* allow_partial */) {
return usb_ffs_do_aio<true>(h, data, len);
}
static int usb_ffs_io_uring_write(usb_handle* h, const void* data, int len) {
return usb_ffs_do_aio<false>(h, data, len);
}
void exit_io_uring_ffs(usb_handle* h) {
io_uring_queue_exit(&h->ring);
}
bool init_io_uring_ffs(usb_handle* h, size_t queue_depth) {
const auto err = io_uring_queue_init(queue_depth, &h->ring, 0);
if (err) {
LOG(ERROR) << "Failed to initialize io_uring of depth " << queue_depth << ": "
<< strerror(err);
return false;
}
h->write = usb_ffs_io_uring_write;
h->read = usb_ffs_io_uring_read;
return true;
}
|