[bpf-next,v3,06/10] selftests/bpf: Add test for io_uring BPF iterators

Message ID	20211201042333.2035153-7-memxor@gmail.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <linux-fsdevel-owner@kernel.org> From: Kumar Kartikeya Dwivedi <memxor@gmail.com> To: bpf@vger.kernel.org Cc: Jens Axboe <axboe@kernel.dk>, Pavel Begunkov <asml.silence@gmail.com>, io-uring@vger.kernel.org, Alexei Starovoitov <ast@kernel.org>, Daniel Borkmann <daniel@iogearbox.net>, Andrii Nakryiko <andrii@kernel.org>, Yonghong Song <yhs@fb.com>, Pavel Emelyanov <ovzxemul@gmail.com>, Alexander Mikhalitsyn <alexander@mihalicyn.com>, Andrei Vagin <avagin@gmail.com>, criu@openvz.org, linux-fsdevel@vger.kernel.org Subject: [PATCH bpf-next v3 06/10] selftests/bpf: Add test for io_uring BPF iterators Date: Wed, 1 Dec 2021 09:53:29 +0530 Message-Id: <20211201042333.2035153-7-memxor@gmail.com> In-Reply-To: <20211201042333.2035153-1-memxor@gmail.com> References: <20211201042333.2035153-1-memxor@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk
Series	Introduce BPF iterators for io_uring and epoll \| expand [bpf-next,v3,00/10] Introduce BPF iterators for io_uring and epoll [bpf-next,v3,01/10] io_uring: Implement eBPF iterator for registered buffers [bpf-next,v3,02/10] bpf: Add bpf_page_to_pfn helper [bpf-next,v3,03/10] io_uring: Implement eBPF iterator for registered files [bpf-next,v3,04/10] epoll: Implement eBPF iterator for registered items [bpf-next,v3,05/10] bpftool: Output io_uring iterator info [bpf-next,v3,06/10] selftests/bpf: Add test for io_uring BPF iterators [bpf-next,v3,07/10] selftests/bpf: Add test for epoll BPF iterator [bpf-next,v3,08/10] selftests/bpf: Test partial reads for io_uring, epoll iterators [bpf-next,v3,09/10] selftests/bpf: Fix btf_dump test for bpf_iter_link_info [RFC,bpf-next,v3,10/10] samples/bpf: Add example to checkpoint/restore io_uring

diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c index 0b996be923b5..13ea2eaed032 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c @@ -1,6 +1,10 @@ // SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2020 Facebook */ +#include <sys/stat.h> +#include <sys/mman.h> #include <test_progs.h> +#include <linux/io_uring.h> + #include "bpf_iter_ipv6_route.skel.h" #include "bpf_iter_netlink.skel.h" #include "bpf_iter_bpf_map.skel.h" @@ -26,6 +30,7 @@ #include "bpf_iter_bpf_sk_storage_map.skel.h" #include "bpf_iter_test_kern5.skel.h" #include "bpf_iter_test_kern6.skel.h" +#include "bpf_iter_io_uring.skel.h" static int duration; @@ -1239,6 +1244,248 @@ static void test_task_vma(void) bpf_iter_task_vma__destroy(skel); } +static int sys_io_uring_setup(u32 entries, struct io_uring_params *p) +{ + return syscall(__NR_io_uring_setup, entries, p); +} + +static int io_uring_register_bufs(int io_uring_fd, struct iovec *iovs, unsigned int nr) +{ + return syscall(__NR_io_uring_register, io_uring_fd, + IORING_REGISTER_BUFFERS, iovs, nr); +} + +static int io_uring_register_files(int io_uring_fd, int *fds, unsigned int nr) +{ + return syscall(__NR_io_uring_register, io_uring_fd, + IORING_REGISTER_FILES, fds, nr); +} + +static unsigned long long page_addr_to_pfn(unsigned long addr) +{ + int page_size = sysconf(_SC_PAGE_SIZE), fd, ret; + unsigned long long pfn; + + if (page_size < 0) + return 0; + fd = open("/proc/self/pagemap", O_RDONLY); + if (fd < 0) + return 0; + + ret = pread(fd, &pfn, sizeof(pfn), (addr / page_size) * 8); + close(fd); + if (ret < 0) + return 0; + /* Bits 0-54 have PFN for non-swapped page */ + return pfn & 0x7fffffffffffff; +} + +static int io_uring_inode_match(int link_fd, int io_uring_fd) +{ + struct bpf_link_info linfo = {}; + __u32 info_len = sizeof(linfo); + struct stat st; + int ret; + + ret = fstat(io_uring_fd, &st); + if (ret < 0) + return -errno; + + ret = bpf_obj_get_info_by_fd(link_fd, &linfo, &info_len); + if (ret < 0) + return -errno; + + ASSERT_EQ(st.st_ino, linfo.iter.io_uring.inode, "io_uring inode matches"); + return 0; +} + +void test_io_uring_buf(void) +{ + DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts); + char rbuf[4096], buf[4096] = "B\n"; + union bpf_iter_link_info linfo; + struct bpf_iter_io_uring *skel; + int ret, fd, i, len = 128; + struct io_uring_params p; + struct iovec iovs[8]; + int iter_fd; + char *str; + + opts.link_info = &linfo; + opts.link_info_len = sizeof(linfo); + + skel = bpf_iter_io_uring__open_and_load(); + if (!ASSERT_OK_PTR(skel, "bpf_iter_io_uring__open_and_load")) + return; + + for (i = 0; i < ARRAY_SIZE(iovs); i++) { + iovs[i].iov_len = len; + iovs[i].iov_base = mmap(NULL, len, PROT_READ | PROT_WRITE, + MAP_ANONYMOUS | MAP_SHARED, -1, 0); + if (iovs[i].iov_base == MAP_FAILED) + goto end; + len *= 2; + } + + memset(&p, 0, sizeof(p)); + fd = sys_io_uring_setup(1, &p); + if (!ASSERT_GE(fd, 0, "io_uring_setup")) + goto end; + + linfo.io_uring.io_uring_fd = fd; + skel->links.dump_io_uring_buf = bpf_program__attach_iter(skel->progs.dump_io_uring_buf, + &opts); + if (!ASSERT_OK_PTR(skel->links.dump_io_uring_buf, "bpf_program__attach_iter")) + goto end_close_fd; + + if (!ASSERT_OK(io_uring_inode_match(bpf_link__fd(skel->links.dump_io_uring_buf), fd), "inode match")) + goto end_close_fd; + + ret = io_uring_register_bufs(fd, iovs, ARRAY_SIZE(iovs)); + if (!ASSERT_OK(ret, "io_uring_register_bufs")) + goto end_close_fd; + + /* "B\n" */ + len = 2; + str = buf + len; + for (int j = 0; j < ARRAY_SIZE(iovs); j++) { + ret = snprintf(str, sizeof(buf) - len, "%d:0x%lx:%zu\n", j, + (unsigned long)iovs[j].iov_base, + iovs[j].iov_len); + if (!ASSERT_GE(ret, 0, "snprintf") || !ASSERT_LT(ret, sizeof(buf) - len, "snprintf")) + goto end_close_fd; + len += ret; + str += ret; + + ret = snprintf(str, sizeof(buf) - len, "`-PFN for bvec[0]=%llu\n", + page_addr_to_pfn((unsigned long)iovs[j].iov_base)); + if (!ASSERT_GE(ret, 0, "snprintf") || !ASSERT_LT(ret, sizeof(buf) - len, "snprintf")) + goto end_close_fd; + len += ret; + str += ret; + } + + ret = snprintf(str, sizeof(buf) - len, "E:%zu\n", ARRAY_SIZE(iovs)); + if (!ASSERT_GE(ret, 0, "snprintf") || !ASSERT_LT(ret, sizeof(buf) - len, "snprintf")) + goto end_close_fd; + + iter_fd = bpf_iter_create(bpf_link__fd(skel->links.dump_io_uring_buf)); + if (!ASSERT_GE(iter_fd, 0, "bpf_iter_create")) + goto end_close_fd; + + ret = read_fd_into_buffer(iter_fd, rbuf, sizeof(rbuf)); + if (!ASSERT_GT(ret, 0, "read_fd_into_buffer")) + goto end_close_iter; + + if (!ASSERT_OK(strcmp(rbuf, buf), "compare iterator output")) { + puts("=== Expected Output ==="); + printf("%s", buf); + puts("==== Actual Output ===="); + printf("%s", rbuf); + puts("======================="); + } +end_close_iter: + close(iter_fd); +end_close_fd: + close(fd); +end: + while (i--) + munmap(iovs[i].iov_base, iovs[i].iov_len); + bpf_iter_io_uring__destroy(skel); +} + +void test_io_uring_file(void) +{ + int reg_files[] = { [0 ... 7] = -1 }; + DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts); + char buf[4096] = "B\n", rbuf[4096] = {}, *str; + union bpf_iter_link_info linfo = {}; + struct bpf_iter_io_uring *skel; + int iter_fd, fd, len = 0, ret; + struct io_uring_params p; + + opts.link_info = &linfo; + opts.link_info_len = sizeof(linfo); + + skel = bpf_iter_io_uring__open_and_load(); + if (!ASSERT_OK_PTR(skel, "bpf_iter_io_uring__open_and_load")) + return; + + /* "B\n" */ + len = 2; + str = buf + len; + ret = snprintf(str, sizeof(buf) - len, "B\n"); + for (int i = 0; i < ARRAY_SIZE(reg_files); i++) { + char templ[] = "/tmp/io_uringXXXXXX"; + const char *name, *def = "<none>"; + + /* create sparse set */ + if (i & 1) { + name = def; + } else { + reg_files[i] = mkstemp(templ); + if (!ASSERT_GE(reg_files[i], 0, templ)) + goto end_close_reg_files; + name = templ; + ASSERT_OK(unlink(name), "unlink"); + } + ret = snprintf(str, sizeof(buf) - len, "%d:%s%s\n", i, name, name != def ? " (deleted)" : ""); + if (!ASSERT_GE(ret, 0, "snprintf") || !ASSERT_LT(ret, sizeof(buf) - len, "snprintf")) + goto end_close_reg_files; + len += ret; + str += ret; + } + + ret = snprintf(str, sizeof(buf) - len, "E:%zu\n", ARRAY_SIZE(reg_files)); + if (!ASSERT_GE(ret, 0, "snprintf") || !ASSERT_LT(ret, sizeof(buf) - len, "snprintf")) + goto end_close_reg_files; + + memset(&p, 0, sizeof(p)); + fd = sys_io_uring_setup(1, &p); + if (!ASSERT_GE(fd, 0, "io_uring_setup")) + goto end_close_reg_files; + + linfo.io_uring.io_uring_fd = fd; + skel->links.dump_io_uring_file = bpf_program__attach_iter(skel->progs.dump_io_uring_file, + &opts); + if (!ASSERT_OK_PTR(skel->links.dump_io_uring_file, "bpf_program__attach_iter")) + goto end_close_fd; + + if (!ASSERT_OK(io_uring_inode_match(bpf_link__fd(skel->links.dump_io_uring_file), fd), "inode match")) + goto end_close_fd; + + iter_fd = bpf_iter_create(bpf_link__fd(skel->links.dump_io_uring_file)); + if (!ASSERT_GE(iter_fd, 0, "bpf_iter_create")) + goto end; + + ret = io_uring_register_files(fd, reg_files, ARRAY_SIZE(reg_files)); + if (!ASSERT_OK(ret, "io_uring_register_files")) + goto end_iter_fd; + + ret = read_fd_into_buffer(iter_fd, rbuf, sizeof(rbuf)); + if (!ASSERT_GT(ret, 0, "read_fd_into_buffer(iterator_fd, buf)")) + goto end_iter_fd; + + if (!ASSERT_OK(strcmp(rbuf, buf), "compare iterator output")) { + puts("=== Expected Output ==="); + printf("%s", buf); + puts("==== Actual Output ===="); + printf("%s", rbuf); + puts("======================="); + } +end_iter_fd: + close(iter_fd); +end_close_fd: + close(fd); +end_close_reg_files: + for (int i = 0; i < ARRAY_SIZE(reg_files); i++) { + if (reg_files[i] != -1) + close(reg_files[i]); + } +end: + bpf_iter_io_uring__destroy(skel); +} + void test_bpf_iter(void) { if (test__start_subtest("btf_id_or_null")) @@ -1299,4 +1546,8 @@ void test_bpf_iter(void) test_rdonly_buf_out_of_bound(); if (test__start_subtest("buf-neg-offset")) test_buf_neg_offset(); + if (test__start_subtest("io_uring_buf")) + test_io_uring_buf(); + if (test__start_subtest("io_uring_file")) + test_io_uring_file(); } diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_io_uring.c b/tools/testing/selftests/bpf/progs/bpf_iter_io_uring.c new file mode 100644 index 000000000000..caf8bd0bf8d4 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/bpf_iter_io_uring.c @@ -0,0 +1,50 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "bpf_iter.h" +#include <bpf/bpf_helpers.h> + +SEC("iter/io_uring_buf") +int dump_io_uring_buf(struct bpf_iter__io_uring_buf *ctx) +{ + struct io_mapped_ubuf *ubuf = ctx->ubuf; + struct seq_file *seq = ctx->meta->seq; + unsigned int index = ctx->index; + + if (!ctx->meta->seq_num) + BPF_SEQ_PRINTF(seq, "B\n"); + + if (ubuf) { + BPF_SEQ_PRINTF(seq, "%u:0x%lx:%lu\n", index, (unsigned long)ubuf->ubuf, + (unsigned long)ubuf->ubuf_end - ubuf->ubuf); + BPF_SEQ_PRINTF(seq, "`-PFN for bvec[0]=%lu\n", + (unsigned long)bpf_page_to_pfn(ubuf->bvec[0].bv_page)); + } else { + BPF_SEQ_PRINTF(seq, "E:%u\n", index); + } + return 0; +} + +SEC("iter/io_uring_file") +int dump_io_uring_file(struct bpf_iter__io_uring_file *ctx) +{ + struct seq_file *seq = ctx->meta->seq; + unsigned int index = ctx->index; + struct file *file = ctx->file; + char buf[256] = ""; + + if (!ctx->meta->seq_num) + BPF_SEQ_PRINTF(seq, "B\n"); + /* for io_uring_file iterator, this is the terminating condition */ + if (ctx->ctx->nr_user_files == index) { + BPF_SEQ_PRINTF(seq, "E:%u\n", index); + return 0; + } + if (file) { + bpf_d_path(&file->f_path, buf, sizeof(buf)); + BPF_SEQ_PRINTF(seq, "%u:%s\n", index, buf); + } else { + BPF_SEQ_PRINTF(seq, "%u:<none>\n", index); + } + return 0; +} + +char _license[] SEC("license") = "GPL";

[bpf-next,v3,06/10] selftests/bpf: Add test for io_uring BPF iterators

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Patch