From: Hou Tao houtao1@huawei.com

hulk inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I7Y9JD CVE: NA

---------------------------

Add a writable bare tracepoint fs_file_read() and a bare tracepoint fs_file_release().

A version field is added to fs_file_read() to support extension of fs_file_read_ctx in future.

These two tracepoints need to be exported and will be used by filesystem kernel module.

Signed-off-by: Hou Tao houtao1@huawei.com Acked-by: fang wei fangwei1@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com Signed-off-by: Zhihao Cheng chengzhihao1@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: ZhaoLong Wang wangzhaolong1@huawei.com

Conflicts: include/linux/fs.h --- fs/read_write.c | 5 +++++ include/linux/fs.h | 17 +++++++++++++++++ include/trace/events/fs.h | 33 +++++++++++++++++++++++++++++++++ 3 files changed, 55 insertions(+) create mode 100644 include/trace/events/fs.h

diff --git a/fs/read_write.c b/fs/read_write.c index a21ba3be7dbe..68bd1e644628 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -24,6 +24,8 @@

#include <linux/uaccess.h> #include <asm/unistd.h> +#define CREATE_TRACE_POINTS +#include <trace/events/fs.h>

const struct file_operations generic_ro_fops = { .llseek = generic_file_llseek, @@ -1718,3 +1720,6 @@ int generic_file_rw_checks(struct file *file_in, struct file *file_out)

return 0; } + +EXPORT_TRACEPOINT_SYMBOL_GPL(fs_file_read); +EXPORT_TRACEPOINT_SYMBOL_GPL(fs_file_release); diff --git a/include/linux/fs.h b/include/linux/fs.h index 931fe15dd17c..d29fd8eaf2f2 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3212,4 +3212,21 @@ extern int vfs_fadvise(struct file *file, loff_t offset, loff_t len, extern int generic_fadvise(struct file *file, loff_t offset, loff_t len, int advice);

+struct fs_file_read_ctx { + const unsigned char *name; + unsigned int f_ctl_mode; + unsigned int rsvd; + /* clear from f_ctl_mode */ + unsigned int clr_f_ctl_mode; + /* set into f_ctl_mode */ + unsigned int set_f_ctl_mode; + unsigned long key; + /* file size */ + long long i_size; + /* previous page index */ + long long prev_index; + /* current page index */ + long long index; +}; + #endif /* _LINUX_FS_H */ diff --git a/include/trace/events/fs.h b/include/trace/events/fs.h new file mode 100644 index 000000000000..ee82dad9d9da --- /dev/null +++ b/include/trace/events/fs.h @@ -0,0 +1,33 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#undef TRACE_SYSTEM +#define TRACE_SYSTEM fs + +#if !defined(_TRACE_FS_H) || defined(TRACE_HEADER_MULTI_READ) +#define _TRACE_FS_H + +#include <linux/types.h> +#include <linux/tracepoint.h> +#include <linux/fs.h> + +#undef FS_DECLARE_TRACE +#ifdef DECLARE_TRACE_WRITABLE +#define FS_DECLARE_TRACE(call, proto, args, size) \ + DECLARE_TRACE_WRITABLE(call, PARAMS(proto), PARAMS(args), size) +#else +#define FS_DECLARE_TRACE(call, proto, args, size) \ + DECLARE_TRACE(call, PARAMS(proto), PARAMS(args)) +#endif + +FS_DECLARE_TRACE(fs_file_read, + TP_PROTO(struct fs_file_read_ctx *ctx, int version), + TP_ARGS(ctx, version), + sizeof(struct fs_file_read_ctx)); + +DECLARE_TRACE(fs_file_release, + TP_PROTO(struct inode *inode, struct file *filp), + TP_ARGS(inode, filp)); + +#endif /* _TRACE_FS_H */ + +/* This part must be outside protection */ +#include <trace/define_trace.h>

From: Hou Tao houtao1@huawei.com

hulk inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I7Y9JD CVE: NA

---------------------------

Use fs_file_read_do_trace() and trace_fs_file_release() to do that.

Signed-off-by: Hou Tao houtao1@huawei.com Acked-by: fang wei fangwei1@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com Signed-off-by: Zhihao Cheng chengzhihao1@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: ZhaoLong Wang wangzhaolong1@huawei.com

Conflicts: fs/xfs/xfs_file.c --- fs/xfs/xfs_file.c | 3 +++ 1 file changed, 3 insertions(+)

diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index aede746541f8..66ab9108fefd 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -31,6 +31,7 @@ #include <linux/mman.h> #include <linux/fadvise.h> #include <linux/mount.h> +#include <trace/events/fs.h>

static const struct vm_operations_struct xfs_file_vm_ops;

@@ -270,6 +271,7 @@ xfs_file_buffered_read( ssize_t ret;

trace_xfs_file_buffered_read(iocb, to); + fs_file_read_do_trace(iocb);

ret = xfs_ilock_iocb(iocb, XFS_IOLOCK_SHARED); if (ret) @@ -1205,6 +1207,7 @@ xfs_file_release( struct inode *inode, struct file *filp) { + trace_fs_file_release(inode, filp); return xfs_release(XFS_I(inode)); }

From: Hou Tao houtao1@huawei.com

hulk inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I7Y9JD CVE: NA

---------------------------

It attaches eBPF program into fs_file_read() and fs_file_release() respectively. The program for fs_file_read() will record read history, calculate read pattern and set f_mode for specific file, And program for fs_file_release() will clean the saved read history.

Signed-off-by: Hou Tao houtao1@huawei.com Reviewed-by: Kuohai Xu xukuohai@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com Signed-off-by: Zhihao Cheng chengzhihao1@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com Signed-off-by: ZhaoLong Wang wangzhaolong1@huawei.com

Conflicts: tools/testing/selftests/bpf/Makefile --- tools/testing/selftests/bpf/Makefile | 1 + .../testing/selftests/bpf/file_read_pattern.c | 73 +++++++++ .../bpf/progs/file_read_pattern_prog.c | 142 ++++++++++++++++++ 3 files changed, 216 insertions(+) create mode 100644 tools/testing/selftests/bpf/file_read_pattern.c create mode 100644 tools/testing/selftests/bpf/progs/file_read_pattern_prog.c

diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index 28d2c77262be..ab25af503d60 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -41,6 +41,7 @@ TEST_GEN_PROGS = test_verifier test_tag test_maps test_lru_map test_lpm_map test test_cgroup_storage \ test_tcpnotify_user test_sysctl \ test_progs-no_alu32 +TEST_GEN_PROGS += file_read_pattern

# Also test bpf-gcc, if present ifneq ($(BPF_GCC),) diff --git a/tools/testing/selftests/bpf/file_read_pattern.c b/tools/testing/selftests/bpf/file_read_pattern.c new file mode 100644 index 000000000000..81e3a49f0424 --- /dev/null +++ b/tools/testing/selftests/bpf/file_read_pattern.c @@ -0,0 +1,73 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2021. Huawei Technologies Co., Ltd */ +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <errno.h> +#include <unistd.h> +#include <linux/bpf.h> +#include <linux/err.h> +#include <bpf/bpf.h> +#include <bpf/libbpf.h> + +#include "bpf_rlimit.h" + +#define READ_TP_NAME "fs_file_read" +#define RELEASE_TP_NAME "fs_file_release" + +int main(int argc, char *argv[]) +{ + const char *name = "./file_read_pattern_prog.o"; + struct bpf_object *obj; + const char *prog_name; + struct bpf_program *prog; + int unused; + int err; + int read_fd; + int release_fd; + + err = bpf_prog_load(name, BPF_PROG_TYPE_UNSPEC, &obj, &unused); + if (err) { + printf("Failed to load program\n"); + return err; + } + + prog_name = "raw_tracepoint.w/" READ_TP_NAME; + prog = bpf_object__find_program_by_title(obj, prog_name); + if (!prog) { + printf("no prog %s\n", prog_name); + err = -EINVAL; + goto out; + } + + read_fd = bpf_raw_tracepoint_open(READ_TP_NAME, bpf_program__fd(prog)); + if (read_fd < 0) { + err = -errno; + printf("Failed to attach raw tracepoint %s\n", READ_TP_NAME); + goto out; + } + + prog_name = "raw_tracepoint/" RELEASE_TP_NAME; + prog = bpf_object__find_program_by_title(obj, prog_name); + if (!prog) { + printf("no prog %s\n", prog_name); + err = -EINVAL; + goto out; + } + + release_fd = bpf_raw_tracepoint_open(RELEASE_TP_NAME, + bpf_program__fd(prog)); + if (release_fd < 0) { + err = -errno; + printf("Failed to attach raw tracepoint %s\n", RELEASE_TP_NAME); + goto out; + } + + pause(); + + close(release_fd); + close(read_fd); +out: + bpf_object__close(obj); + return err; +} diff --git a/tools/testing/selftests/bpf/progs/file_read_pattern_prog.c b/tools/testing/selftests/bpf/progs/file_read_pattern_prog.c new file mode 100644 index 000000000000..cd2dcd7c64bb --- /dev/null +++ b/tools/testing/selftests/bpf/progs/file_read_pattern_prog.c @@ -0,0 +1,142 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2021. Huawei Technologies Co., Ltd */ +#include <stdbool.h> +#include <string.h> +#include <linux/bpf.h> + +#include <bpf/bpf_helpers.h> + +#ifndef __always_inline +#define __always_inline inline __attribute__((always_inline)) +#endif + +/* Need to keep consistent with definitions in include/linux/fs.h */ +#define FMODE_CTL_RANDOM 0x1 +#define FMODE_CTL_WILLNEED 0x2 + +struct fs_file_read_ctx { + const unsigned char *name; + unsigned int f_ctl_mode; + unsigned int rsvd; + /* clear from f_ctl_mode */ + unsigned int clr_f_ctl_mode; + /* set into f_ctl_mode */ + unsigned int set_f_ctl_mode; + unsigned long key; + /* file size */ + long long i_size; + /* previous page index */ + long long prev_index; + /* current page index */ + long long index; +}; + +struct fs_file_read_args { + struct fs_file_read_ctx *ctx; + int version; +}; + +struct fs_file_release_args { + void *inode; + void *filp; +}; + +struct file_rd_hist { + __u64 last_nsec; + __u32 seq_nr; + __u32 tot_nr; +}; + +struct bpf_map_def SEC("maps") htab = { + .type = BPF_MAP_TYPE_HASH, + .key_size = sizeof(long), + .value_size = sizeof(struct file_rd_hist), + .max_entries = 10000, +}; + +static __always_inline bool is_expected_file(void *name) +{ + char prefix[5]; + int err; + + err = bpf_probe_read_str(&prefix, sizeof(prefix), name); + if (err <= 0) + return false; + return !strncmp(prefix, "blk_", 4); +} + +SEC("raw_tracepoint.w/fs_file_read") +int fs_file_read(struct fs_file_read_args *args) +{ + const char fmt[] = "elapsed %llu, seq %u, tot %u\n"; + struct fs_file_read_ctx *rd_ctx = args->ctx; + struct file_rd_hist *hist; + struct file_rd_hist new_hist; + __u64 key; + __u64 now; + bool first; + + if (!is_expected_file((void *)rd_ctx->name)) + return 0; + + if (rd_ctx->i_size <= (4 << 20)) { + rd_ctx->set_f_ctl_mode = FMODE_CTL_WILLNEED; + return 0; + } + + first = false; + now = bpf_ktime_get_ns(); + key = rd_ctx->key; + hist = bpf_map_lookup_elem(&htab, &key); + if (!hist) { + __builtin_memset(&new_hist, 0, sizeof(new_hist)); + new_hist.last_nsec = now; + first = true; + hist = &new_hist; + } + + if (rd_ctx->index >= rd_ctx->prev_index && + rd_ctx->index - rd_ctx->prev_index <= 1) + hist->seq_nr += 1; + hist->tot_nr += 1; + + bpf_trace_printk(fmt, sizeof(fmt), now - hist->last_nsec, + hist->seq_nr, hist->tot_nr); + + if (first) { + bpf_map_update_elem(&htab, &key, hist, 0); + return 0; + } + + /* 500ms or 10 read */ + if (now - hist->last_nsec >= 500000000ULL || hist->tot_nr >= 10) { + if (hist->tot_nr >= 10) { + if (hist->seq_nr <= hist->tot_nr * 3 / 10) + rd_ctx->set_f_ctl_mode = FMODE_CTL_RANDOM; + else if (hist->seq_nr >= hist->tot_nr * 7 / 10) + rd_ctx->clr_f_ctl_mode = FMODE_CTL_RANDOM; + } + + hist->last_nsec = now; + hist->tot_nr = 0; + hist->seq_nr = 0; + } + + return 0; +} + +SEC("raw_tracepoint/fs_file_release") +int fs_file_release(struct fs_file_release_args *args) +{ + __u64 key = (unsigned long)args->filp; + void *value; + + value = bpf_map_lookup_elem(&htab, &key); + if (value) + bpf_map_delete_elem(&htab, &key); + + return 0; +} + +char _license[] SEC("license") = "GPL"; +__u32 _version SEC("version") = 1;

hulk inclusion category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I7Y9JD CVE: NA

-----------------------------------------

Some APIs are removed and some APIs are changed from libbpf 1.0 or later. The purpose of this patch is to enable the demo to run successfully on libbpf 1.0+.

For details about API changes, see the following link: https://github.com/libbpf/libbpf/wiki/Libbpf:-the-road-to-v1.0 https://github.com/libbpf/libbpf/wiki/Libbpf-1.0-migration-guide

Signed-off-by: ZhaoLong Wang wangzhaolong1@huawei.com --- .../testing/selftests/bpf/file_read_pattern.c | 30 +++++++++---------- .../bpf/progs/file_read_pattern_prog.c | 12 ++++---- 2 files changed, 21 insertions(+), 21 deletions(-)

diff --git a/tools/testing/selftests/bpf/file_read_pattern.c b/tools/testing/selftests/bpf/file_read_pattern.c index 81e3a49f0424..365f58d1a70f 100644 --- a/tools/testing/selftests/bpf/file_read_pattern.c +++ b/tools/testing/selftests/bpf/file_read_pattern.c @@ -10,32 +10,33 @@ #include <bpf/bpf.h> #include <bpf/libbpf.h>

-#include "bpf_rlimit.h" - #define READ_TP_NAME "fs_file_read" #define RELEASE_TP_NAME "fs_file_release"

int main(int argc, char *argv[]) { - const char *name = "./file_read_pattern_prog.o"; + const char *name = "./file_read_pattern_prog.bpf.o"; struct bpf_object *obj; - const char *prog_name; struct bpf_program *prog; - int unused; - int err; + int err = 0; int read_fd; int release_fd;

- err = bpf_prog_load(name, BPF_PROG_TYPE_UNSPEC, &obj, &unused); - if (err) { - printf("Failed to load program\n"); + obj = bpf_object__open_file(name, NULL); + if (!obj) { + printf("Failed to open program: %s\n", name); return err; }

- prog_name = "raw_tracepoint.w/" READ_TP_NAME; - prog = bpf_object__find_program_by_title(obj, prog_name); + err = bpf_object__load(obj); + if (err) { + printf("failed to load program: %s\n", name); + goto out; + } + + prog = bpf_object__find_program_by_name(obj, READ_TP_NAME); if (!prog) { - printf("no prog %s\n", prog_name); + printf("no prog %s\n", READ_TP_NAME); err = -EINVAL; goto out; } @@ -47,10 +48,9 @@ int main(int argc, char *argv[]) goto out; }

- prog_name = "raw_tracepoint/" RELEASE_TP_NAME; - prog = bpf_object__find_program_by_title(obj, prog_name); + prog = bpf_object__find_program_by_name(obj, RELEASE_TP_NAME); if (!prog) { - printf("no prog %s\n", prog_name); + printf("no prog %s\n", RELEASE_TP_NAME); err = -EINVAL; goto out; } diff --git a/tools/testing/selftests/bpf/progs/file_read_pattern_prog.c b/tools/testing/selftests/bpf/progs/file_read_pattern_prog.c index 1d9f199d8370..4fd25c242805 100644 --- a/tools/testing/selftests/bpf/progs/file_read_pattern_prog.c +++ b/tools/testing/selftests/bpf/progs/file_read_pattern_prog.c @@ -47,12 +47,12 @@ struct file_rd_hist { __u32 tot_nr; };

-struct bpf_map_def SEC("maps") htab = { - .type = BPF_MAP_TYPE_HASH, - .key_size = sizeof(long), - .value_size = sizeof(struct file_rd_hist), - .max_entries = 10000, -}; +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __type(key, long); + __type(value, struct file_rd_hist); + __uint(max_entries, 10000); +} htab SEC(".maps");

static __always_inline bool is_expected_file(void *name) {