Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2024-05-13

We've added 119 non-merge commits during the last 14 day(s) which contain
a total of 134 files changed, 9462 insertions(+), 4742 deletions(-).

The main changes are:

1) Add BPF JIT support for 32-bit ARCv2 processors, from Shahab Vahedi.

2) Add BPF range computation improvements to the verifier in particular
   around XOR and OR operators, refactoring of checks for range computation
   and relaxing MUL range computation so that src_reg can also be an unknown
   scalar, from Cupertino Miranda.

3) Add support to attach kprobe BPF programs through kprobe_multi link in
   a session mode, meaning, a BPF program is attached to both function entry
   and return, the entry program can decide if the return program gets
   executed and the entry program can share u64 cookie value with return
   program. Session mode is a common use-case for tetragon and bpftrace,
   from Jiri Olsa.

4) Fix a potential overflow in libbpf's ring__consume_n() and improve libbpf
   as well as BPF selftest's struct_ops handling, from Andrii Nakryiko.

5) Improvements to BPF selftests in context of BPF gcc backend,
   from Jose E. Marchesi & David Faust.

6) Migrate remaining BPF selftest tests from test_sock_addr.c to prog_test-
   -style in order to retire the old test, run it in BPF CI and additionally
   expand test coverage, from Jordan Rife.

7) Big batch for BPF selftest refactoring in order to remove duplicate code
   around common network helpers, from Geliang Tang.

8) Another batch of improvements to BPF selftests to retire obsolete
   bpf_tcp_helpers.h as everything is available vmlinux.h,
   from Martin KaFai Lau.

9) Fix BPF map tear-down to not walk the map twice on free when both timer
   and wq is used, from Benjamin Tissoires.

10) Fix BPF verifier assumptions about socket->sk that it can be non-NULL,
    from Alexei Starovoitov.

11) Change BTF build scripts to using --btf_features for pahole v1.26+,
    from Alan Maguire.

12) Small improvements to BPF reusing struct_size() and krealloc_array(),
    from Andy Shevchenko.

13) Fix s390 JIT to emit a barrier for BPF_FETCH instructions,
    from Ilya Leoshkevich.

14) Extend TCP ->cong_control() callback in order to feed in ack and
    flag parameters and allow write-access to tp->snd_cwnd_stamp
    from BPF program, from Miao Xu.

15) Add support for internal-only per-CPU instructions to inline
    bpf_get_smp_processor_id() helper call for arm64 and riscv64 BPF JITs,
    from Puranjay Mohan.

16) Follow-up to remove the redundant ethtool.h from tooling infrastructure,
    from Tushar Vyavahare.

17) Extend libbpf to support "module:<function>" syntax for tracing
    programs, from Viktor Malik.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (119 commits)
  bpf: make list_for_each_entry portable
  bpf: ignore expected GCC warning in test_global_func10.c
  bpf: disable strict aliasing in test_global_func9.c
  selftests/bpf: Free strdup memory in xdp_hw_metadata
  selftests/bpf: Fix a few tests for GCC related warnings.
  bpf: avoid gcc overflow warning in test_xdp_vlan.c
  tools: remove redundant ethtool.h from tooling infra
  selftests/bpf: Expand ATTACH_REJECT tests
  selftests/bpf: Expand getsockname and getpeername tests
  sefltests/bpf: Expand sockaddr hook deny tests
  selftests/bpf: Expand sockaddr program return value tests
  selftests/bpf: Retire test_sock_addr.(c|sh)
  selftests/bpf: Remove redundant sendmsg test cases
  selftests/bpf: Migrate ATTACH_REJECT test cases
  selftests/bpf: Migrate expected_attach_type tests
  selftests/bpf: Migrate wildcard destination rewrite test
  selftests/bpf: Migrate sendmsg6 v4 mapped address tests
  selftests/bpf: Migrate sendmsg deny test cases
  selftests/bpf: Migrate WILDCARD_IP test
  selftests/bpf: Handle SYSCALL_EPERM and SYSCALL_ENOTSUPP test cases
  ...
====================

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: kuba-moo

Documentation/admin-guide/sysctl/net.rst

@@ -72,6 +72,7 @@ two flavors of JITs, the newer eBPF JIT currently supported on:
   - riscv64
   - riscv32
   - loongarch64
+  - arc
 
 And the older cBPF JIT supported on the following archs:
 

Documentation/networking/filter.rst

@@ -513,7 +513,7 @@ JIT compiler
 ------------
 
 The Linux kernel has a built-in BPF JIT compiler for x86_64, SPARC,
-PowerPC, ARM, ARM64, MIPS, RISC-V and s390 and can be enabled through
+PowerPC, ARM, ARM64, MIPS, RISC-V, s390, and ARC and can be enabled through
 CONFIG_BPF_JIT. The JIT compiler is transparently invoked for each
 attached filter from user space or for internal kernel users if it has
 been previously enabled by root::
@@ -650,7 +650,7 @@ before a conversion to the new layout is being done behind the scenes!
 
 Currently, the classic BPF format is being used for JITing on most
 32-bit architectures, whereas x86-64, aarch64, s390x, powerpc64,
-sparc64, arm32, riscv64, riscv32, loongarch64 perform JIT compilation
+sparc64, arm32, riscv64, riscv32, loongarch64, arc perform JIT compilation
 from eBPF instruction set.
 
 Testing

MAINTAINERS

@@ -3712,6 +3712,12 @@ S:	Maintained
 F:	Documentation/devicetree/bindings/iio/imu/bosch,bmi323.yaml
 F:	drivers/iio/imu/bmi323/
 
+BPF JIT for ARC
+M:	Shahab Vahedi <[email protected]>
+L:	[email protected]
+S:	Maintained
+F:	arch/arc/net/
+
 BPF JIT for ARM
 M:	Russell King <[email protected]>
 M:	Puranjay Mohan <[email protected]>

arch/arc/Kbuild

@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-y += kernel/
 obj-y += mm/
+obj-y += net/
 
 # for cleaning
 subdir- += boot

arch/arc/Kconfig

@@ -51,6 +51,7 @@ config ARC
 	select PCI_SYSCALL if PCI
 	select HAVE_ARCH_JUMP_LABEL if ISA_ARCV2 && !CPU_ENDIAN_BE32
 	select TRACE_IRQFLAGS_SUPPORT
+	select HAVE_EBPF_JIT if ISA_ARCV2
 
 config LOCKDEP_SUPPORT
 	def_bool y

arch/arc/net/Makefile

@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+ifeq ($(CONFIG_ISA_ARCV2),y)
+	obj-$(CONFIG_BPF_JIT) += bpf_jit_core.o
+	obj-$(CONFIG_BPF_JIT) += bpf_jit_arcv2.o
+endif

arch/arc/net/bpf_jit.h

@@ -0,0 +1,164 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * The interface that a back-end should provide to bpf_jit_core.c.
+ *
+ * Copyright (c) 2024 Synopsys Inc.
+ * Author: Shahab Vahedi <[email protected]>
+ */
+
+#ifndef _ARC_BPF_JIT_H
+#define _ARC_BPF_JIT_H
+
+#include <linux/bpf.h>
+#include <linux/filter.h>
+
+/* Print debug info and assert. */
+//#define ARC_BPF_JIT_DEBUG
+
+/* Determine the address type of the target. */
+#ifdef CONFIG_ISA_ARCV2
+#define ARC_ADDR u32
+#endif
+
+/*
+ * For the translation of some BPF instructions, a temporary register
+ * might be needed for some interim data.
+ */
+#define JIT_REG_TMP MAX_BPF_JIT_REG
+
+/*
+ * Buffer access: If buffer "b" is not NULL, advance by "n" bytes.
+ *
+ * This macro must be used in any place that potentially requires a
+ * "buf + len". This way, we make sure that the "buf" argument for
+ * the underlying "arc_*(buf, ...)" ends up as NULL instead of something
+ * like "0+4" or "0+8", etc. Those "arc_*()" functions check their "buf"
+ * value to decide if instructions should be emitted or not.
+ */
+#define BUF(b, n) (((b) != NULL) ? ((b) + (n)) : (b))
+
+/************** Functions that the back-end must provide **************/
+/* Extension for 32-bit operations. */
+inline u8 zext(u8 *buf, u8 rd);
+/***** Moves *****/
+u8 mov_r32(u8 *buf, u8 rd, u8 rs, u8 sign_ext);
+u8 mov_r32_i32(u8 *buf, u8 reg, s32 imm);
+u8 mov_r64(u8 *buf, u8 rd, u8 rs, u8 sign_ext);
+u8 mov_r64_i32(u8 *buf, u8 reg, s32 imm);
+u8 mov_r64_i64(u8 *buf, u8 reg, u32 lo, u32 hi);
+/***** Loads and stores *****/
+u8 load_r(u8 *buf, u8 rd, u8 rs, s16 off, u8 size, bool sign_ext);
+u8 store_r(u8 *buf, u8 rd, u8 rs, s16 off, u8 size);
+u8 store_i(u8 *buf, s32 imm, u8 rd, s16 off, u8 size);
+/***** Addition *****/
+u8 add_r32(u8 *buf, u8 rd, u8 rs);
+u8 add_r32_i32(u8 *buf, u8 rd, s32 imm);
+u8 add_r64(u8 *buf, u8 rd, u8 rs);
+u8 add_r64_i32(u8 *buf, u8 rd, s32 imm);
+/***** Subtraction *****/
+u8 sub_r32(u8 *buf, u8 rd, u8 rs);
+u8 sub_r32_i32(u8 *buf, u8 rd, s32 imm);
+u8 sub_r64(u8 *buf, u8 rd, u8 rs);
+u8 sub_r64_i32(u8 *buf, u8 rd, s32 imm);
+/***** Multiplication *****/
+u8 mul_r32(u8 *buf, u8 rd, u8 rs);
+u8 mul_r32_i32(u8 *buf, u8 rd, s32 imm);
+u8 mul_r64(u8 *buf, u8 rd, u8 rs);
+u8 mul_r64_i32(u8 *buf, u8 rd, s32 imm);
+/***** Division *****/
+u8 div_r32(u8 *buf, u8 rd, u8 rs, bool sign_ext);
+u8 div_r32_i32(u8 *buf, u8 rd, s32 imm, bool sign_ext);
+/***** Remainder *****/
+u8 mod_r32(u8 *buf, u8 rd, u8 rs, bool sign_ext);
+u8 mod_r32_i32(u8 *buf, u8 rd, s32 imm, bool sign_ext);
+/***** Bitwise AND *****/
+u8 and_r32(u8 *buf, u8 rd, u8 rs);
+u8 and_r32_i32(u8 *buf, u8 rd, s32 imm);
+u8 and_r64(u8 *buf, u8 rd, u8 rs);
+u8 and_r64_i32(u8 *buf, u8 rd, s32 imm);
+/***** Bitwise OR *****/
+u8 or_r32(u8 *buf, u8 rd, u8 rs);
+u8 or_r32_i32(u8 *buf, u8 rd, s32 imm);
+u8 or_r64(u8 *buf, u8 rd, u8 rs);
+u8 or_r64_i32(u8 *buf, u8 rd, s32 imm);
+/***** Bitwise XOR *****/
+u8 xor_r32(u8 *buf, u8 rd, u8 rs);
+u8 xor_r32_i32(u8 *buf, u8 rd, s32 imm);
+u8 xor_r64(u8 *buf, u8 rd, u8 rs);
+u8 xor_r64_i32(u8 *buf, u8 rd, s32 imm);
+/***** Bitwise Negate *****/
+u8 neg_r32(u8 *buf, u8 r);
+u8 neg_r64(u8 *buf, u8 r);
+/***** Bitwise left shift *****/
+u8 lsh_r32(u8 *buf, u8 rd, u8 rs);
+u8 lsh_r32_i32(u8 *buf, u8 rd, u8 imm);
+u8 lsh_r64(u8 *buf, u8 rd, u8 rs);
+u8 lsh_r64_i32(u8 *buf, u8 rd, s32 imm);
+/***** Bitwise right shift (logical) *****/
+u8 rsh_r32(u8 *buf, u8 rd, u8 rs);
+u8 rsh_r32_i32(u8 *buf, u8 rd, u8 imm);
+u8 rsh_r64(u8 *buf, u8 rd, u8 rs);
+u8 rsh_r64_i32(u8 *buf, u8 rd, s32 imm);
+/***** Bitwise right shift (arithmetic) *****/
+u8 arsh_r32(u8 *buf, u8 rd, u8 rs);
+u8 arsh_r32_i32(u8 *buf, u8 rd, u8 imm);
+u8 arsh_r64(u8 *buf, u8 rd, u8 rs);
+u8 arsh_r64_i32(u8 *buf, u8 rd, s32 imm);
+/***** Frame related *****/
+u32 mask_for_used_regs(u8 bpf_reg, bool is_call);
+u8 arc_prologue(u8 *buf, u32 usage, u16 frame_size);
+u8 arc_epilogue(u8 *buf, u32 usage, u16 frame_size);
+/***** Jumps *****/
+/*
+ * Different sorts of conditions (ARC enum as opposed to BPF_*).
+ *
+ * Do not change the order of enums here. ARC_CC_SLE+1 is used
+ * to determine the number of JCCs.
+ */
+enum ARC_CC {
+	ARC_CC_UGT = 0,		/* unsigned >  */
+	ARC_CC_UGE,		/* unsigned >= */
+	ARC_CC_ULT,		/* unsigned <  */
+	ARC_CC_ULE,		/* unsigned <= */
+	ARC_CC_SGT,		/*   signed >  */
+	ARC_CC_SGE,		/*   signed >= */
+	ARC_CC_SLT,		/*   signed <  */
+	ARC_CC_SLE,		/*   signed <= */
+	ARC_CC_AL,		/* always      */
+	ARC_CC_EQ,		/*          == */
+	ARC_CC_NE,		/*          != */
+	ARC_CC_SET,		/* test        */
+	ARC_CC_LAST
+};
+
+/*
+ * A few notes:
+ *
+ * - check_jmp_*() are prerequisites before calling the gen_jmp_*().
+ *   They return "true" if the jump is possible and "false" otherwise.
+ *
+ * - The notion of "*_off" is to emphasize that these parameters are
+ *   merely offsets in the JIT stream and not absolute addresses. One
+ *   can look at them as addresses if the JIT code would start from
+ *   address 0x0000_0000. Nonetheless, since the buffer address for the
+ *   JIT is on a word-aligned address, this works and actually makes
+ *   things simpler (offsets are in the range of u32 which is more than
+ *   enough).
+ */
+bool check_jmp_32(u32 curr_off, u32 targ_off, u8 cond);
+bool check_jmp_64(u32 curr_off, u32 targ_off, u8 cond);
+u8 gen_jmp_32(u8 *buf, u8 rd, u8 rs, u8 cond, u32 c_off, u32 t_off);
+u8 gen_jmp_64(u8 *buf, u8 rd, u8 rs, u8 cond, u32 c_off, u32 t_off);
+/***** Miscellaneous *****/
+u8 gen_func_call(u8 *buf, ARC_ADDR func_addr, bool external_func);
+u8 arc_to_bpf_return(u8 *buf);
+/*
+ * - Perform byte swaps on "rd" based on the "size".
+ * - If "force" is set, do it unconditionally. Otherwise, consider the
+ *   desired "endian"ness and the host endianness.
+ * - For data "size"s up to 32 bits, perform a zero-extension if asked
+ *   by the "do_zext" boolean.
+ */
+u8 gen_swap(u8 *buf, u8 rd, u8 size, u8 endian, bool force, bool do_zext);
+
+#endif /* _ARC_BPF_JIT_H */