summaryrefslogtreecommitdiffstats
path: root/arch/arm/net
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
commit034dd340b08be1f2f0477ad16131d609f9dbd53c (patch)
tree2536f4b2d7893ccd916b5abdf3c454ad6edc03c2 /arch/arm/net
downloadlinux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.tar.gz
linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.zip
Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure
Diffstat (limited to 'arch/arm/net')
-rw-r--r--arch/arm/net/Makefile4
-rw-r--r--arch/arm/net/bpf_jit_32.c2272
-rw-r--r--arch/arm/net/bpf_jit_32.h280
3 files changed, 2556 insertions, 0 deletions
diff --git a/arch/arm/net/Makefile b/arch/arm/net/Makefile
new file mode 100644
index 000000000..3354b3e11
--- /dev/null
+++ b/arch/arm/net/Makefile
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
+# ARM-specific networking code
+
+obj-$(CONFIG_BPF_JIT) += bpf_jit_32.o
diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c
new file mode 100644
index 000000000..9ede81afb
--- /dev/null
+++ b/arch/arm/net/bpf_jit_32.c
@@ -0,0 +1,2272 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Just-In-Time compiler for eBPF filters on 32bit ARM
+ *
+ * Copyright (c) 2023 Puranjay Mohan <puranjay12@gmail.com>
+ * Copyright (c) 2017 Shubham Bansal <illusionist.neo@gmail.com>
+ * Copyright (c) 2011 Mircea Gherzan <mgherzan@gmail.com>
+ */
+
+#include <linux/bpf.h>
+#include <linux/bitops.h>
+#include <linux/compiler.h>
+#include <linux/errno.h>
+#include <linux/filter.h>
+#include <linux/netdevice.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+#include <linux/if_vlan.h>
+#include <linux/math64.h>
+
+#include <asm/cacheflush.h>
+#include <asm/hwcap.h>
+#include <asm/opcodes.h>
+#include <asm/system_info.h>
+
+#include "bpf_jit_32.h"
+
+/*
+ * eBPF prog stack layout:
+ *
+ * high
+ * original ARM_SP => +-----+
+ * | | callee saved registers
+ * +-----+ <= (BPF_FP + SCRATCH_SIZE)
+ * | ... | eBPF JIT scratch space
+ * eBPF fp register => +-----+
+ * (BPF_FP) | ... | eBPF prog stack
+ * +-----+
+ * |RSVD | JIT scratchpad
+ * current ARM_SP => +-----+ <= (BPF_FP - STACK_SIZE + SCRATCH_SIZE)
+ * | ... | caller-saved registers
+ * +-----+
+ * | ... | arguments passed on stack
+ * ARM_SP during call => +-----|
+ * | |
+ * | ... | Function call stack
+ * | |
+ * +-----+
+ * low
+ *
+ * The callee saved registers depends on whether frame pointers are enabled.
+ * With frame pointers (to be compliant with the ABI):
+ *
+ * high
+ * original ARM_SP => +--------------+ \
+ * | pc | |
+ * current ARM_FP => +--------------+ } callee saved registers
+ * |r4-r9,fp,ip,lr| |
+ * +--------------+ /
+ * low
+ *
+ * Without frame pointers:
+ *
+ * high
+ * original ARM_SP => +--------------+
+ * | r4-r9,fp,lr | callee saved registers
+ * current ARM_FP => +--------------+
+ * low
+ *
+ * When popping registers off the stack at the end of a BPF function, we
+ * reference them via the current ARM_FP register.
+ *
+ * Some eBPF operations are implemented via a call to a helper function.
+ * Such calls are "invisible" in the eBPF code, so it is up to the calling
+ * program to preserve any caller-saved ARM registers during the call. The
+ * JIT emits code to push and pop those registers onto the stack, immediately
+ * above the callee stack frame.
+ */
+#define CALLEE_MASK (1 << ARM_R4 | 1 << ARM_R5 | 1 << ARM_R6 | \
+ 1 << ARM_R7 | 1 << ARM_R8 | 1 << ARM_R9 | \
+ 1 << ARM_FP)
+#define CALLEE_PUSH_MASK (CALLEE_MASK | 1 << ARM_LR)
+#define CALLEE_POP_MASK (CALLEE_MASK | 1 << ARM_PC)
+
+#define CALLER_MASK (1 << ARM_R0 | 1 << ARM_R1 | 1 << ARM_R2 | 1 << ARM_R3)
+
+enum {
+ /* Stack layout - these are offsets from (top of stack - 4) */
+ BPF_R2_HI,
+ BPF_R2_LO,
+ BPF_R3_HI,
+ BPF_R3_LO,
+ BPF_R4_HI,
+ BPF_R4_LO,
+ BPF_R5_HI,
+ BPF_R5_LO,
+ BPF_R7_HI,
+ BPF_R7_LO,
+ BPF_R8_HI,
+ BPF_R8_LO,
+ BPF_R9_HI,
+ BPF_R9_LO,
+ BPF_FP_HI,
+ BPF_FP_LO,
+ BPF_TC_HI,
+ BPF_TC_LO,
+ BPF_AX_HI,
+ BPF_AX_LO,
+ /* Stack space for BPF_REG_2, BPF_REG_3, BPF_REG_4,
+ * BPF_REG_5, BPF_REG_7, BPF_REG_8, BPF_REG_9,
+ * BPF_REG_FP and Tail call counts.
+ */
+ BPF_JIT_SCRATCH_REGS,
+};
+
+/*
+ * Negative "register" values indicate the register is stored on the stack
+ * and are the offset from the top of the eBPF JIT scratch space.
+ */
+#define STACK_OFFSET(k) (-4 - (k) * 4)
+#define SCRATCH_SIZE (BPF_JIT_SCRATCH_REGS * 4)
+
+#ifdef CONFIG_FRAME_POINTER
+#define EBPF_SCRATCH_TO_ARM_FP(x) ((x) - 4 * hweight16(CALLEE_PUSH_MASK) - 4)
+#else
+#define EBPF_SCRATCH_TO_ARM_FP(x) (x)
+#endif
+
+#define TMP_REG_1 (MAX_BPF_JIT_REG + 0) /* TEMP Register 1 */
+#define TMP_REG_2 (MAX_BPF_JIT_REG + 1) /* TEMP Register 2 */
+#define TCALL_CNT (MAX_BPF_JIT_REG + 2) /* Tail Call Count */
+
+#define FLAG_IMM_OVERFLOW (1 << 0)
+
+/*
+ * Map eBPF registers to ARM 32bit registers or stack scratch space.
+ *
+ * 1. First argument is passed using the arm 32bit registers and rest of the
+ * arguments are passed on stack scratch space.
+ * 2. First callee-saved argument is mapped to arm 32 bit registers and rest
+ * arguments are mapped to scratch space on stack.
+ * 3. We need two 64 bit temp registers to do complex operations on eBPF
+ * registers.
+ *
+ * As the eBPF registers are all 64 bit registers and arm has only 32 bit
+ * registers, we have to map each eBPF registers with two arm 32 bit regs or
+ * scratch memory space and we have to build eBPF 64 bit register from those.
+ *
+ */
+static const s8 bpf2a32[][2] = {
+ /* return value from in-kernel function, and exit value from eBPF */
+ [BPF_REG_0] = {ARM_R1, ARM_R0},
+ /* arguments from eBPF program to in-kernel function */
+ [BPF_REG_1] = {ARM_R3, ARM_R2},
+ /* Stored on stack scratch space */
+ [BPF_REG_2] = {STACK_OFFSET(BPF_R2_HI), STACK_OFFSET(BPF_R2_LO)},
+ [BPF_REG_3] = {STACK_OFFSET(BPF_R3_HI), STACK_OFFSET(BPF_R3_LO)},
+ [BPF_REG_4] = {STACK_OFFSET(BPF_R4_HI), STACK_OFFSET(BPF_R4_LO)},
+ [BPF_REG_5] = {STACK_OFFSET(BPF_R5_HI), STACK_OFFSET(BPF_R5_LO)},
+ /* callee saved registers that in-kernel function will preserve */
+ [BPF_REG_6] = {ARM_R5, ARM_R4},
+ /* Stored on stack scratch space */
+ [BPF_REG_7] = {STACK_OFFSET(BPF_R7_HI), STACK_OFFSET(BPF_R7_LO)},
+ [BPF_REG_8] = {STACK_OFFSET(BPF_R8_HI), STACK_OFFSET(BPF_R8_LO)},
+ [BPF_REG_9] = {STACK_OFFSET(BPF_R9_HI), STACK_OFFSET(BPF_R9_LO)},
+ /* Read only Frame Pointer to access Stack */
+ [BPF_REG_FP] = {STACK_OFFSET(BPF_FP_HI), STACK_OFFSET(BPF_FP_LO)},
+ /* Temporary Register for BPF JIT, can be used
+ * for constant blindings and others.
+ */
+ [TMP_REG_1] = {ARM_R7, ARM_R6},
+ [TMP_REG_2] = {ARM_R9, ARM_R8},
+ /* Tail call count. Stored on stack scratch space. */
+ [TCALL_CNT] = {STACK_OFFSET(BPF_TC_HI), STACK_OFFSET(BPF_TC_LO)},
+ /* temporary register for blinding constants.
+ * Stored on stack scratch space.
+ */
+ [BPF_REG_AX] = {STACK_OFFSET(BPF_AX_HI), STACK_OFFSET(BPF_AX_LO)},
+};
+
+#define dst_lo dst[1]
+#define dst_hi dst[0]
+#define src_lo src[1]
+#define src_hi src[0]
+
+/*
+ * JIT Context:
+ *
+ * prog : bpf_prog
+ * idx : index of current last JITed instruction.
+ * prologue_bytes : bytes used in prologue.
+ * epilogue_offset : offset of epilogue starting.
+ * offsets : array of eBPF instruction offsets in
+ * JITed code.
+ * target : final JITed code.
+ * epilogue_bytes : no of bytes used in epilogue.
+ * imm_count : no of immediate counts used for global
+ * variables.
+ * imms : array of global variable addresses.
+ */
+
+struct jit_ctx {
+ const struct bpf_prog *prog;
+ unsigned int idx;
+ unsigned int prologue_bytes;
+ unsigned int epilogue_offset;
+ unsigned int cpu_architecture;
+ u32 flags;
+ u32 *offsets;
+ u32 *target;
+ u32 stack_size;
+#if __LINUX_ARM_ARCH__ < 7
+ u16 epilogue_bytes;
+ u16 imm_count;
+ u32 *imms;
+#endif
+};
+
+/*
+ * Wrappers which handle both OABI and EABI and assures Thumb2 interworking
+ * (where the assembly routines like __aeabi_uidiv could cause problems).
+ */
+static u32 jit_udiv32(u32 dividend, u32 divisor)
+{
+ return dividend / divisor;
+}
+
+static u32 jit_mod32(u32 dividend, u32 divisor)
+{
+ return dividend % divisor;
+}
+
+static s32 jit_sdiv32(s32 dividend, s32 divisor)
+{
+ return dividend / divisor;
+}
+
+static s32 jit_smod32(s32 dividend, s32 divisor)
+{
+ return dividend % divisor;
+}
+
+/* Wrappers for 64-bit div/mod */
+static u64 jit_udiv64(u64 dividend, u64 divisor)
+{
+ return div64_u64(dividend, divisor);
+}
+
+static u64 jit_mod64(u64 dividend, u64 divisor)
+{
+ u64 rem;
+
+ div64_u64_rem(dividend, divisor, &rem);
+ return rem;
+}
+
+static s64 jit_sdiv64(s64 dividend, s64 divisor)
+{
+ return div64_s64(dividend, divisor);
+}
+
+static s64 jit_smod64(s64 dividend, s64 divisor)
+{
+ u64 q;
+
+ q = div64_s64(dividend, divisor);
+
+ return dividend - q * divisor;
+}
+
+static inline void _emit(int cond, u32 inst, struct jit_ctx *ctx)
+{
+ inst |= (cond << 28);
+ inst = __opcode_to_mem_arm(inst);
+
+ if (ctx->target != NULL)
+ ctx->target[ctx->idx] = inst;
+
+ ctx->idx++;
+}
+
+/*
+ * Emit an instruction that will be executed unconditionally.
+ */
+static inline void emit(u32 inst, struct jit_ctx *ctx)
+{
+ _emit(ARM_COND_AL, inst, ctx);
+}
+
+/*
+ * This is rather horrid, but necessary to convert an integer constant
+ * to an immediate operand for the opcodes, and be able to detect at
+ * build time whether the constant can't be converted (iow, usable in
+ * BUILD_BUG_ON()).
+ */
+#define imm12val(v, s) (rol32(v, (s)) | (s) << 7)
+#define const_imm8m(x) \
+ ({ int r; \
+ u32 v = (x); \
+ if (!(v & ~0x000000ff)) \
+ r = imm12val(v, 0); \
+ else if (!(v & ~0xc000003f)) \
+ r = imm12val(v, 2); \
+ else if (!(v & ~0xf000000f)) \
+ r = imm12val(v, 4); \
+ else if (!(v & ~0xfc000003)) \
+ r = imm12val(v, 6); \
+ else if (!(v & ~0xff000000)) \
+ r = imm12val(v, 8); \
+ else if (!(v & ~0x3fc00000)) \
+ r = imm12val(v, 10); \
+ else if (!(v & ~0x0ff00000)) \
+ r = imm12val(v, 12); \
+ else if (!(v & ~0x03fc0000)) \
+ r = imm12val(v, 14); \
+ else if (!(v & ~0x00ff0000)) \
+ r = imm12val(v, 16); \
+ else if (!(v & ~0x003fc000)) \
+ r = imm12val(v, 18); \
+ else if (!(v & ~0x000ff000)) \
+ r = imm12val(v, 20); \
+ else if (!(v & ~0x0003fc00)) \
+ r = imm12val(v, 22); \
+ else if (!(v & ~0x0000ff00)) \
+ r = imm12val(v, 24); \
+ else if (!(v & ~0x00003fc0)) \
+ r = imm12val(v, 26); \
+ else if (!(v & ~0x00000ff0)) \
+ r = imm12val(v, 28); \
+ else if (!(v & ~0x000003fc)) \
+ r = imm12val(v, 30); \
+ else \
+ r = -1; \
+ r; })
+
+/*
+ * Checks if immediate value can be converted to imm12(12 bits) value.
+ */
+static int imm8m(u32 x)
+{
+ u32 rot;
+
+ for (rot = 0; rot < 16; rot++)
+ if ((x & ~ror32(0xff, 2 * rot)) == 0)
+ return rol32(x, 2 * rot) | (rot << 8);
+ return -1;
+}
+
+#define imm8m(x) (__builtin_constant_p(x) ? const_imm8m(x) : imm8m(x))
+
+static u32 arm_bpf_ldst_imm12(u32 op, u8 rt, u8 rn, s16 imm12)
+{
+ op |= rt << 12 | rn << 16;
+ if (imm12 >= 0)
+ op |= ARM_INST_LDST__U;
+ else
+ imm12 = -imm12;
+ return op | (imm12 & ARM_INST_LDST__IMM12);
+}
+
+static u32 arm_bpf_ldst_imm8(u32 op, u8 rt, u8 rn, s16 imm8)
+{
+ op |= rt << 12 | rn << 16;
+ if (imm8 >= 0)
+ op |= ARM_INST_LDST__U;
+ else
+ imm8 = -imm8;
+ return op | (imm8 & 0xf0) << 4 | (imm8 & 0x0f);
+}
+
+#define ARM_LDR_I(rt, rn, off) arm_bpf_ldst_imm12(ARM_INST_LDR_I, rt, rn, off)
+#define ARM_LDRB_I(rt, rn, off) arm_bpf_ldst_imm12(ARM_INST_LDRB_I, rt, rn, off)
+#define ARM_LDRD_I(rt, rn, off) arm_bpf_ldst_imm8(ARM_INST_LDRD_I, rt, rn, off)
+#define ARM_LDRH_I(rt, rn, off) arm_bpf_ldst_imm8(ARM_INST_LDRH_I, rt, rn, off)
+
+#define ARM_LDRSH_I(rt, rn, off) arm_bpf_ldst_imm8(ARM_INST_LDRSH_I, rt, rn, off)
+#define ARM_LDRSB_I(rt, rn, off) arm_bpf_ldst_imm8(ARM_INST_LDRSB_I, rt, rn, off)
+
+#define ARM_STR_I(rt, rn, off) arm_bpf_ldst_imm12(ARM_INST_STR_I, rt, rn, off)
+#define ARM_STRB_I(rt, rn, off) arm_bpf_ldst_imm12(ARM_INST_STRB_I, rt, rn, off)
+#define ARM_STRD_I(rt, rn, off) arm_bpf_ldst_imm8(ARM_INST_STRD_I, rt, rn, off)
+#define ARM_STRH_I(rt, rn, off) arm_bpf_ldst_imm8(ARM_INST_STRH_I, rt, rn, off)
+
+/*
+ * Initializes the JIT space with undefined instructions.
+ */
+static void jit_fill_hole(void *area, unsigned int size)
+{
+ u32 *ptr;
+ /* We are guaranteed to have aligned memory. */
+ for (ptr = area; size >= sizeof(u32); size -= sizeof(u32))
+ *ptr++ = __opcode_to_mem_arm(ARM_INST_UDF);
+}
+
+#if defined(CONFIG_AEABI) && (__LINUX_ARM_ARCH__ >= 5)
+/* EABI requires the stack to be aligned to 64-bit boundaries */
+#define STACK_ALIGNMENT 8
+#else
+/* Stack must be aligned to 32-bit boundaries */
+#define STACK_ALIGNMENT 4
+#endif
+
+/* total stack size used in JITed code */
+#define _STACK_SIZE (ctx->prog->aux->stack_depth + SCRATCH_SIZE)
+#define STACK_SIZE ALIGN(_STACK_SIZE, STACK_ALIGNMENT)
+
+#if __LINUX_ARM_ARCH__ < 7
+
+static u16 imm_offset(u32 k, struct jit_ctx *ctx)
+{
+ unsigned int i = 0, offset;
+ u16 imm;
+
+ /* on the "fake" run we just count them (duplicates included) */
+ if (ctx->target == NULL) {
+ ctx->imm_count++;
+ return 0;
+ }
+
+ while ((i < ctx->imm_count) && ctx->imms[i]) {
+ if (ctx->imms[i] == k)
+ break;
+ i++;
+ }
+
+ if (ctx->imms[i] == 0)
+ ctx->imms[i] = k;
+
+ /* constants go just after the epilogue */
+ offset = ctx->offsets[ctx->prog->len - 1] * 4;
+ offset += ctx->prologue_bytes;
+ offset += ctx->epilogue_bytes;
+ offset += i * 4;
+
+ ctx->target[offset / 4] = k;
+
+ /* PC in ARM mode == address of the instruction + 8 */
+ imm = offset - (8 + ctx->idx * 4);
+
+ if (imm & ~0xfff) {
+ /*
+ * literal pool is too far, signal it into flags. we
+ * can only detect it on the second pass unfortunately.
+ */
+ ctx->flags |= FLAG_IMM_OVERFLOW;
+ return 0;
+ }
+
+ return imm;
+}
+
+#endif /* __LINUX_ARM_ARCH__ */
+
+static inline int bpf2a32_offset(int bpf_to, int bpf_from,
+ const struct jit_ctx *ctx) {
+ int to, from;
+
+ if (ctx->target == NULL)
+ return 0;
+ to = ctx->offsets[bpf_to];
+ from = ctx->offsets[bpf_from];
+
+ return to - from - 1;
+}
+
+/*
+ * Move an immediate that's not an imm8m to a core register.
+ */
+static inline void emit_mov_i_no8m(const u8 rd, u32 val, struct jit_ctx *ctx)
+{
+#if __LINUX_ARM_ARCH__ < 7
+ emit(ARM_LDR_I(rd, ARM_PC, imm_offset(val, ctx)), ctx);
+#else
+ emit(ARM_MOVW(rd, val & 0xffff), ctx);
+ if (val > 0xffff)
+ emit(ARM_MOVT(rd, val >> 16), ctx);
+#endif
+}
+
+static inline void emit_mov_i(const u8 rd, u32 val, struct jit_ctx *ctx)
+{
+ int imm12 = imm8m(val);
+
+ if (imm12 >= 0)
+ emit(ARM_MOV_I(rd, imm12), ctx);
+ else
+ emit_mov_i_no8m(rd, val, ctx);
+}
+
+static void emit_bx_r(u8 tgt_reg, struct jit_ctx *ctx)
+{
+ if (elf_hwcap & HWCAP_THUMB)
+ emit(ARM_BX(tgt_reg), ctx);
+ else
+ emit(ARM_MOV_R(ARM_PC, tgt_reg), ctx);
+}
+
+static inline void emit_blx_r(u8 tgt_reg, struct jit_ctx *ctx)
+{
+#if __LINUX_ARM_ARCH__ < 5
+ emit(ARM_MOV_R(ARM_LR, ARM_PC), ctx);
+ emit_bx_r(tgt_reg, ctx);
+#else
+ emit(ARM_BLX_R(tgt_reg), ctx);
+#endif
+}
+
+static inline int epilogue_offset(const struct jit_ctx *ctx)
+{
+ int to, from;
+ /* No need for 1st dummy run */
+ if (ctx->target == NULL)
+ return 0;
+ to = ctx->epilogue_offset;
+ from = ctx->idx;
+
+ return to - from - 2;
+}
+
+static inline void emit_udivmod(u8 rd, u8 rm, u8 rn, struct jit_ctx *ctx, u8 op, u8 sign)
+{
+ const int exclude_mask = BIT(ARM_R0) | BIT(ARM_R1);
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ u32 dst;
+
+#if __LINUX_ARM_ARCH__ == 7
+ if (elf_hwcap & HWCAP_IDIVA) {
+ if (op == BPF_DIV) {
+ emit(sign ? ARM_SDIV(rd, rm, rn) : ARM_UDIV(rd, rm, rn), ctx);
+ } else {
+ emit(sign ? ARM_SDIV(ARM_IP, rm, rn) : ARM_UDIV(ARM_IP, rm, rn), ctx);
+ emit(ARM_MLS(rd, rn, ARM_IP, rm), ctx);
+ }
+ return;
+ }
+#endif
+
+ /*
+ * For BPF_ALU | BPF_DIV | BPF_K instructions
+ * As ARM_R1 and ARM_R0 contains 1st argument of bpf
+ * function, we need to save it on caller side to save
+ * it from getting destroyed within callee.
+ * After the return from the callee, we restore ARM_R0
+ * ARM_R1.
+ */
+ if (rn != ARM_R1) {
+ emit(ARM_MOV_R(tmp[0], ARM_R1), ctx);
+ emit(ARM_MOV_R(ARM_R1, rn), ctx);
+ }
+ if (rm != ARM_R0) {
+ emit(ARM_MOV_R(tmp[1], ARM_R0), ctx);
+ emit(ARM_MOV_R(ARM_R0, rm), ctx);
+ }
+
+ /* Push caller-saved registers on stack */
+ emit(ARM_PUSH(CALLER_MASK & ~exclude_mask), ctx);
+
+ /* Call appropriate function */
+ if (sign) {
+ if (op == BPF_DIV)
+ dst = (u32)jit_sdiv32;
+ else
+ dst = (u32)jit_smod32;
+ } else {
+ if (op == BPF_DIV)
+ dst = (u32)jit_udiv32;
+ else
+ dst = (u32)jit_mod32;
+ }
+
+ emit_mov_i(ARM_IP, dst, ctx);
+ emit_blx_r(ARM_IP, ctx);
+
+ /* Restore caller-saved registers from stack */
+ emit(ARM_POP(CALLER_MASK & ~exclude_mask), ctx);
+
+ /* Save return value */
+ if (rd != ARM_R0)
+ emit(ARM_MOV_R(rd, ARM_R0), ctx);
+
+ /* Restore ARM_R0 and ARM_R1 */
+ if (rn != ARM_R1)
+ emit(ARM_MOV_R(ARM_R1, tmp[0]), ctx);
+ if (rm != ARM_R0)
+ emit(ARM_MOV_R(ARM_R0, tmp[1]), ctx);
+}
+
+static inline void emit_udivmod64(const s8 *rd, const s8 *rm, const s8 *rn, struct jit_ctx *ctx,
+ u8 op, u8 sign)
+{
+ u32 dst;
+
+ /* Push caller-saved registers on stack */
+ emit(ARM_PUSH(CALLER_MASK), ctx);
+
+ /*
+ * As we are implementing 64-bit div/mod as function calls, We need to put the dividend in
+ * R0-R1 and the divisor in R2-R3. As we have already pushed these registers on the stack,
+ * we can recover them later after returning from the function call.
+ */
+ if (rm[1] != ARM_R0 || rn[1] != ARM_R2) {
+ /*
+ * Move Rm to {R1, R0} if it is not already there.
+ */
+ if (rm[1] != ARM_R0) {
+ if (rn[1] == ARM_R0)
+ emit(ARM_PUSH(BIT(ARM_R0) | BIT(ARM_R1)), ctx);
+ emit(ARM_MOV_R(ARM_R1, rm[0]), ctx);
+ emit(ARM_MOV_R(ARM_R0, rm[1]), ctx);
+ if (rn[1] == ARM_R0) {
+ emit(ARM_POP(BIT(ARM_R2) | BIT(ARM_R3)), ctx);
+ goto cont;
+ }
+ }
+ /*
+ * Move Rn to {R3, R2} if it is not already there.
+ */
+ if (rn[1] != ARM_R2) {
+ emit(ARM_MOV_R(ARM_R3, rn[0]), ctx);
+ emit(ARM_MOV_R(ARM_R2, rn[1]), ctx);
+ }
+ }
+
+cont:
+
+ /* Call appropriate function */
+ if (sign) {
+ if (op == BPF_DIV)
+ dst = (u32)jit_sdiv64;
+ else
+ dst = (u32)jit_smod64;
+ } else {
+ if (op == BPF_DIV)
+ dst = (u32)jit_udiv64;
+ else
+ dst = (u32)jit_mod64;
+ }
+
+ emit_mov_i(ARM_IP, dst, ctx);
+ emit_blx_r(ARM_IP, ctx);
+
+ /* Save return value */
+ if (rd[1] != ARM_R0) {
+ emit(ARM_MOV_R(rd[0], ARM_R1), ctx);
+ emit(ARM_MOV_R(rd[1], ARM_R0), ctx);
+ }
+
+ /* Recover {R3, R2} and {R1, R0} from stack if they are not Rd */
+ if (rd[1] != ARM_R0 && rd[1] != ARM_R2) {
+ emit(ARM_POP(CALLER_MASK), ctx);
+ } else if (rd[1] != ARM_R0) {
+ emit(ARM_POP(BIT(ARM_R0) | BIT(ARM_R1)), ctx);
+ emit(ARM_ADD_I(ARM_SP, ARM_SP, 8), ctx);
+ } else {
+ emit(ARM_ADD_I(ARM_SP, ARM_SP, 8), ctx);
+ emit(ARM_POP(BIT(ARM_R2) | BIT(ARM_R3)), ctx);
+ }
+}
+
+/* Is the translated BPF register on stack? */
+static bool is_stacked(s8 reg)
+{
+ return reg < 0;
+}
+
+/* If a BPF register is on the stack (stk is true), load it to the
+ * supplied temporary register and return the temporary register
+ * for subsequent operations, otherwise just use the CPU register.
+ */
+static s8 arm_bpf_get_reg32(s8 reg, s8 tmp, struct jit_ctx *ctx)
+{
+ if (is_stacked(reg)) {
+ emit(ARM_LDR_I(tmp, ARM_FP, EBPF_SCRATCH_TO_ARM_FP(reg)), ctx);
+ reg = tmp;
+ }
+ return reg;
+}
+
+static const s8 *arm_bpf_get_reg64(const s8 *reg, const s8 *tmp,
+ struct jit_ctx *ctx)
+{
+ if (is_stacked(reg[1])) {
+ if (__LINUX_ARM_ARCH__ >= 6 ||
+ ctx->cpu_architecture >= CPU_ARCH_ARMv5TE) {
+ emit(ARM_LDRD_I(tmp[1], ARM_FP,
+ EBPF_SCRATCH_TO_ARM_FP(reg[1])), ctx);
+ } else {
+ emit(ARM_LDR_I(tmp[1], ARM_FP,
+ EBPF_SCRATCH_TO_ARM_FP(reg[1])), ctx);
+ emit(ARM_LDR_I(tmp[0], ARM_FP,
+ EBPF_SCRATCH_TO_ARM_FP(reg[0])), ctx);
+ }
+ reg = tmp;
+ }
+ return reg;
+}
+
+/* If a BPF register is on the stack (stk is true), save the register
+ * back to the stack. If the source register is not the same, then
+ * move it into the correct register.
+ */
+static void arm_bpf_put_reg32(s8 reg, s8 src, struct jit_ctx *ctx)
+{
+ if (is_stacked(reg))
+ emit(ARM_STR_I(src, ARM_FP, EBPF_SCRATCH_TO_ARM_FP(reg)), ctx);
+ else if (reg != src)
+ emit(ARM_MOV_R(reg, src), ctx);
+}
+
+static void arm_bpf_put_reg64(const s8 *reg, const s8 *src,
+ struct jit_ctx *ctx)
+{
+ if (is_stacked(reg[1])) {
+ if (__LINUX_ARM_ARCH__ >= 6 ||
+ ctx->cpu_architecture >= CPU_ARCH_ARMv5TE) {
+ emit(ARM_STRD_I(src[1], ARM_FP,
+ EBPF_SCRATCH_TO_ARM_FP(reg[1])), ctx);
+ } else {
+ emit(ARM_STR_I(src[1], ARM_FP,
+ EBPF_SCRATCH_TO_ARM_FP(reg[1])), ctx);
+ emit(ARM_STR_I(src[0], ARM_FP,
+ EBPF_SCRATCH_TO_ARM_FP(reg[0])), ctx);
+ }
+ } else {
+ if (reg[1] != src[1])
+ emit(ARM_MOV_R(reg[1], src[1]), ctx);
+ if (reg[0] != src[0])
+ emit(ARM_MOV_R(reg[0], src[0]), ctx);
+ }
+}
+
+static inline void emit_a32_mov_i(const s8 dst, const u32 val,
+ struct jit_ctx *ctx)
+{
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+
+ if (is_stacked(dst)) {
+ emit_mov_i(tmp[1], val, ctx);
+ arm_bpf_put_reg32(dst, tmp[1], ctx);
+ } else {
+ emit_mov_i(dst, val, ctx);
+ }
+}
+
+static void emit_a32_mov_i64(const s8 dst[], u64 val, struct jit_ctx *ctx)
+{
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ const s8 *rd = is_stacked(dst_lo) ? tmp : dst;
+
+ emit_mov_i(rd[1], (u32)val, ctx);
+ emit_mov_i(rd[0], val >> 32, ctx);
+
+ arm_bpf_put_reg64(dst, rd, ctx);
+}
+
+/* Sign extended move */
+static inline void emit_a32_mov_se_i64(const bool is64, const s8 dst[],
+ const u32 val, struct jit_ctx *ctx) {
+ u64 val64 = val;
+
+ if (is64 && (val & (1<<31)))
+ val64 |= 0xffffffff00000000ULL;
+ emit_a32_mov_i64(dst, val64, ctx);
+}
+
+static inline void emit_a32_add_r(const u8 dst, const u8 src,
+ const bool is64, const bool hi,
+ struct jit_ctx *ctx) {
+ /* 64 bit :
+ * adds dst_lo, dst_lo, src_lo
+ * adc dst_hi, dst_hi, src_hi
+ * 32 bit :
+ * add dst_lo, dst_lo, src_lo
+ */
+ if (!hi && is64)
+ emit(ARM_ADDS_R(dst, dst, src), ctx);
+ else if (hi && is64)
+ emit(ARM_ADC_R(dst, dst, src), ctx);
+ else
+ emit(ARM_ADD_R(dst, dst, src), ctx);
+}
+
+static inline void emit_a32_sub_r(const u8 dst, const u8 src,
+ const bool is64, const bool hi,
+ struct jit_ctx *ctx) {
+ /* 64 bit :
+ * subs dst_lo, dst_lo, src_lo
+ * sbc dst_hi, dst_hi, src_hi
+ * 32 bit :
+ * sub dst_lo, dst_lo, src_lo
+ */
+ if (!hi && is64)
+ emit(ARM_SUBS_R(dst, dst, src), ctx);
+ else if (hi && is64)
+ emit(ARM_SBC_R(dst, dst, src), ctx);
+ else
+ emit(ARM_SUB_R(dst, dst, src), ctx);
+}
+
+static inline void emit_alu_r(const u8 dst, const u8 src, const bool is64,
+ const bool hi, const u8 op, struct jit_ctx *ctx){
+ switch (BPF_OP(op)) {
+ /* dst = dst + src */
+ case BPF_ADD:
+ emit_a32_add_r(dst, src, is64, hi, ctx);
+ break;
+ /* dst = dst - src */
+ case BPF_SUB:
+ emit_a32_sub_r(dst, src, is64, hi, ctx);
+ break;
+ /* dst = dst | src */
+ case BPF_OR:
+ emit(ARM_ORR_R(dst, dst, src), ctx);
+ break;
+ /* dst = dst & src */
+ case BPF_AND:
+ emit(ARM_AND_R(dst, dst, src), ctx);
+ break;
+ /* dst = dst ^ src */
+ case BPF_XOR:
+ emit(ARM_EOR_R(dst, dst, src), ctx);
+ break;
+ /* dst = dst * src */
+ case BPF_MUL:
+ emit(ARM_MUL(dst, dst, src), ctx);
+ break;
+ /* dst = dst << src */
+ case BPF_LSH:
+ emit(ARM_LSL_R(dst, dst, src), ctx);
+ break;
+ /* dst = dst >> src */
+ case BPF_RSH:
+ emit(ARM_LSR_R(dst, dst, src), ctx);
+ break;
+ /* dst = dst >> src (signed)*/
+ case BPF_ARSH:
+ emit(ARM_MOV_SR(dst, dst, SRTYPE_ASR, src), ctx);
+ break;
+ }
+}
+
+/* ALU operation (64 bit) */
+static inline void emit_a32_alu_r64(const bool is64, const s8 dst[],
+ const s8 src[], struct jit_ctx *ctx,
+ const u8 op) {
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ const s8 *tmp2 = bpf2a32[TMP_REG_2];
+ const s8 *rd;
+
+ rd = arm_bpf_get_reg64(dst, tmp, ctx);
+ if (is64) {
+ const s8 *rs;
+
+ rs = arm_bpf_get_reg64(src, tmp2, ctx);
+
+ /* ALU operation */
+ emit_alu_r(rd[1], rs[1], true, false, op, ctx);
+ emit_alu_r(rd[0], rs[0], true, true, op, ctx);
+ } else {
+ s8 rs;
+
+ rs = arm_bpf_get_reg32(src_lo, tmp2[1], ctx);
+
+ /* ALU operation */
+ emit_alu_r(rd[1], rs, true, false, op, ctx);
+ if (!ctx->prog->aux->verifier_zext)
+ emit_a32_mov_i(rd[0], 0, ctx);
+ }
+
+ arm_bpf_put_reg64(dst, rd, ctx);
+}
+
+/* dst = src (4 bytes)*/
+static inline void emit_a32_mov_r(const s8 dst, const s8 src, struct jit_ctx *ctx) {
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ s8 rt;
+
+ rt = arm_bpf_get_reg32(src, tmp[0], ctx);
+ arm_bpf_put_reg32(dst, rt, ctx);
+}
+
+/* dst = src */
+static inline void emit_a32_mov_r64(const bool is64, const s8 dst[],
+ const s8 src[],
+ struct jit_ctx *ctx) {
+ if (!is64) {
+ emit_a32_mov_r(dst_lo, src_lo, ctx);
+ if (!ctx->prog->aux->verifier_zext)
+ /* Zero out high 4 bytes */
+ emit_a32_mov_i(dst_hi, 0, ctx);
+ } else if (__LINUX_ARM_ARCH__ < 6 &&
+ ctx->cpu_architecture < CPU_ARCH_ARMv5TE) {
+ /* complete 8 byte move */
+ emit_a32_mov_r(dst_lo, src_lo, ctx);
+ emit_a32_mov_r(dst_hi, src_hi, ctx);
+ } else if (is_stacked(src_lo) && is_stacked(dst_lo)) {
+ const u8 *tmp = bpf2a32[TMP_REG_1];
+
+ emit(ARM_LDRD_I(tmp[1], ARM_FP, EBPF_SCRATCH_TO_ARM_FP(src_lo)), ctx);
+ emit(ARM_STRD_I(tmp[1], ARM_FP, EBPF_SCRATCH_TO_ARM_FP(dst_lo)), ctx);
+ } else if (is_stacked(src_lo)) {
+ emit(ARM_LDRD_I(dst[1], ARM_FP, EBPF_SCRATCH_TO_ARM_FP(src_lo)), ctx);
+ } else if (is_stacked(dst_lo)) {
+ emit(ARM_STRD_I(src[1], ARM_FP, EBPF_SCRATCH_TO_ARM_FP(dst_lo)), ctx);
+ } else {
+ emit(ARM_MOV_R(dst[0], src[0]), ctx);
+ emit(ARM_MOV_R(dst[1], src[1]), ctx);
+ }
+}
+
+/* dst = (signed)src */
+static inline void emit_a32_movsx_r64(const bool is64, const u8 off, const s8 dst[], const s8 src[],
+ struct jit_ctx *ctx) {
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ s8 rs;
+ s8 rd;
+
+ if (is_stacked(dst_lo))
+ rd = tmp[1];
+ else
+ rd = dst_lo;
+ rs = arm_bpf_get_reg32(src_lo, rd, ctx);
+ /* rs may be one of src[1], dst[1], or tmp[1] */
+
+ /* Sign extend rs if needed. If off == 32, lower 32-bits of src are moved to dst and sign
+ * extension only happens in the upper 64 bits.
+ */
+ if (off != 32) {
+ /* Sign extend rs into rd */
+ emit(ARM_LSL_I(rd, rs, 32 - off), ctx);
+ emit(ARM_ASR_I(rd, rd, 32 - off), ctx);
+ } else {
+ rd = rs;
+ }
+
+ /* Write rd to dst_lo
+ *
+ * Optimization:
+ * Assume:
+ * 1. dst == src and stacked.
+ * 2. off == 32
+ *
+ * In this case src_lo was loaded into rd(tmp[1]) but rd was not sign extended as off==32.
+ * So, we don't need to write rd back to dst_lo as they have the same value.
+ * This saves us one str instruction.
+ */
+ if (dst_lo != src_lo || off != 32)
+ arm_bpf_put_reg32(dst_lo, rd, ctx);
+
+ if (!is64) {
+ if (!ctx->prog->aux->verifier_zext)
+ /* Zero out high 4 bytes */
+ emit_a32_mov_i(dst_hi, 0, ctx);
+ } else {
+ if (is_stacked(dst_hi)) {
+ emit(ARM_ASR_I(tmp[0], rd, 31), ctx);
+ arm_bpf_put_reg32(dst_hi, tmp[0], ctx);
+ } else {
+ emit(ARM_ASR_I(dst_hi, rd, 31), ctx);
+ }
+ }
+}
+
+/* Shift operations */
+static inline void emit_a32_alu_i(const s8 dst, const u32 val,
+ struct jit_ctx *ctx, const u8 op) {
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ s8 rd;
+
+ rd = arm_bpf_get_reg32(dst, tmp[0], ctx);
+
+ /* Do shift operation */
+ switch (op) {
+ case BPF_LSH:
+ emit(ARM_LSL_I(rd, rd, val), ctx);
+ break;
+ case BPF_RSH:
+ emit(ARM_LSR_I(rd, rd, val), ctx);
+ break;
+ case BPF_ARSH:
+ emit(ARM_ASR_I(rd, rd, val), ctx);
+ break;
+ case BPF_NEG:
+ emit(ARM_RSB_I(rd, rd, val), ctx);
+ break;
+ }
+
+ arm_bpf_put_reg32(dst, rd, ctx);
+}
+
+/* dst = ~dst (64 bit) */
+static inline void emit_a32_neg64(const s8 dst[],
+ struct jit_ctx *ctx){
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ const s8 *rd;
+
+ /* Setup Operand */
+ rd = arm_bpf_get_reg64(dst, tmp, ctx);
+
+ /* Do Negate Operation */
+ emit(ARM_RSBS_I(rd[1], rd[1], 0), ctx);
+ emit(ARM_RSC_I(rd[0], rd[0], 0), ctx);
+
+ arm_bpf_put_reg64(dst, rd, ctx);
+}
+
+/* dst = dst << src */
+static inline void emit_a32_lsh_r64(const s8 dst[], const s8 src[],
+ struct jit_ctx *ctx) {
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ const s8 *tmp2 = bpf2a32[TMP_REG_2];
+ const s8 *rd;
+ s8 rt;
+
+ /* Setup Operands */
+ rt = arm_bpf_get_reg32(src_lo, tmp2[1], ctx);
+ rd = arm_bpf_get_reg64(dst, tmp, ctx);
+
+ /* Do LSH operation */
+ emit(ARM_SUB_I(ARM_IP, rt, 32), ctx);
+ emit(ARM_RSB_I(tmp2[0], rt, 32), ctx);
+ emit(ARM_MOV_SR(ARM_LR, rd[0], SRTYPE_ASL, rt), ctx);
+ emit(ARM_ORR_SR(ARM_LR, ARM_LR, rd[1], SRTYPE_ASL, ARM_IP), ctx);
+ emit(ARM_ORR_SR(ARM_IP, ARM_LR, rd[1], SRTYPE_LSR, tmp2[0]), ctx);
+ emit(ARM_MOV_SR(ARM_LR, rd[1], SRTYPE_ASL, rt), ctx);
+
+ arm_bpf_put_reg32(dst_lo, ARM_LR, ctx);
+ arm_bpf_put_reg32(dst_hi, ARM_IP, ctx);
+}
+
+/* dst = dst >> src (signed)*/
+static inline void emit_a32_arsh_r64(const s8 dst[], const s8 src[],
+ struct jit_ctx *ctx) {
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ const s8 *tmp2 = bpf2a32[TMP_REG_2];
+ const s8 *rd;
+ s8 rt;
+
+ /* Setup Operands */
+ rt = arm_bpf_get_reg32(src_lo, tmp2[1], ctx);
+ rd = arm_bpf_get_reg64(dst, tmp, ctx);
+
+ /* Do the ARSH operation */
+ emit(ARM_RSB_I(ARM_IP, rt, 32), ctx);
+ emit(ARM_SUBS_I(tmp2[0], rt, 32), ctx);
+ emit(ARM_MOV_SR(ARM_LR, rd[1], SRTYPE_LSR, rt), ctx);
+ emit(ARM_ORR_SR(ARM_LR, ARM_LR, rd[0], SRTYPE_ASL, ARM_IP), ctx);
+ _emit(ARM_COND_PL,
+ ARM_ORR_SR(ARM_LR, ARM_LR, rd[0], SRTYPE_ASR, tmp2[0]), ctx);
+ emit(ARM_MOV_SR(ARM_IP, rd[0], SRTYPE_ASR, rt), ctx);
+
+ arm_bpf_put_reg32(dst_lo, ARM_LR, ctx);
+ arm_bpf_put_reg32(dst_hi, ARM_IP, ctx);
+}
+
+/* dst = dst >> src */
+static inline void emit_a32_rsh_r64(const s8 dst[], const s8 src[],
+ struct jit_ctx *ctx) {
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ const s8 *tmp2 = bpf2a32[TMP_REG_2];
+ const s8 *rd;
+ s8 rt;
+
+ /* Setup Operands */
+ rt = arm_bpf_get_reg32(src_lo, tmp2[1], ctx);
+ rd = arm_bpf_get_reg64(dst, tmp, ctx);
+
+ /* Do RSH operation */
+ emit(ARM_RSB_I(ARM_IP, rt, 32), ctx);
+ emit(ARM_SUBS_I(tmp2[0], rt, 32), ctx);
+ emit(ARM_MOV_SR(ARM_LR, rd[1], SRTYPE_LSR, rt), ctx);
+ emit(ARM_ORR_SR(ARM_LR, ARM_LR, rd[0], SRTYPE_ASL, ARM_IP), ctx);
+ emit(ARM_ORR_SR(ARM_LR, ARM_LR, rd[0], SRTYPE_LSR, tmp2[0]), ctx);
+ emit(ARM_MOV_SR(ARM_IP, rd[0], SRTYPE_LSR, rt), ctx);
+
+ arm_bpf_put_reg32(dst_lo, ARM_LR, ctx);
+ arm_bpf_put_reg32(dst_hi, ARM_IP, ctx);
+}
+
+/* dst = dst << val */
+static inline void emit_a32_lsh_i64(const s8 dst[],
+ const u32 val, struct jit_ctx *ctx){
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ const s8 *tmp2 = bpf2a32[TMP_REG_2];
+ const s8 *rd;
+
+ /* Setup operands */
+ rd = arm_bpf_get_reg64(dst, tmp, ctx);
+
+ /* Do LSH operation */
+ if (val < 32) {
+ emit(ARM_MOV_SI(tmp2[0], rd[0], SRTYPE_ASL, val), ctx);
+ emit(ARM_ORR_SI(rd[0], tmp2[0], rd[1], SRTYPE_LSR, 32 - val), ctx);
+ emit(ARM_MOV_SI(rd[1], rd[1], SRTYPE_ASL, val), ctx);
+ } else {
+ if (val == 32)
+ emit(ARM_MOV_R(rd[0], rd[1]), ctx);
+ else
+ emit(ARM_MOV_SI(rd[0], rd[1], SRTYPE_ASL, val - 32), ctx);
+ emit(ARM_EOR_R(rd[1], rd[1], rd[1]), ctx);
+ }
+
+ arm_bpf_put_reg64(dst, rd, ctx);
+}
+
+/* dst = dst >> val */
+static inline void emit_a32_rsh_i64(const s8 dst[],
+ const u32 val, struct jit_ctx *ctx) {
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ const s8 *tmp2 = bpf2a32[TMP_REG_2];
+ const s8 *rd;
+
+ /* Setup operands */
+ rd = arm_bpf_get_reg64(dst, tmp, ctx);
+
+ /* Do LSR operation */
+ if (val == 0) {
+ /* An immediate value of 0 encodes a shift amount of 32
+ * for LSR. To shift by 0, don't do anything.
+ */
+ } else if (val < 32) {
+ emit(ARM_MOV_SI(tmp2[1], rd[1], SRTYPE_LSR, val), ctx);
+ emit(ARM_ORR_SI(rd[1], tmp2[1], rd[0], SRTYPE_ASL, 32 - val), ctx);
+ emit(ARM_MOV_SI(rd[0], rd[0], SRTYPE_LSR, val), ctx);
+ } else if (val == 32) {
+ emit(ARM_MOV_R(rd[1], rd[0]), ctx);
+ emit(ARM_MOV_I(rd[0], 0), ctx);
+ } else {
+ emit(ARM_MOV_SI(rd[1], rd[0], SRTYPE_LSR, val - 32), ctx);
+ emit(ARM_MOV_I(rd[0], 0), ctx);
+ }
+
+ arm_bpf_put_reg64(dst, rd, ctx);
+}
+
+/* dst = dst >> val (signed) */
+static inline void emit_a32_arsh_i64(const s8 dst[],
+ const u32 val, struct jit_ctx *ctx){
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ const s8 *tmp2 = bpf2a32[TMP_REG_2];
+ const s8 *rd;
+
+ /* Setup operands */
+ rd = arm_bpf_get_reg64(dst, tmp, ctx);
+
+ /* Do ARSH operation */
+ if (val == 0) {
+ /* An immediate value of 0 encodes a shift amount of 32
+ * for ASR. To shift by 0, don't do anything.
+ */
+ } else if (val < 32) {
+ emit(ARM_MOV_SI(tmp2[1], rd[1], SRTYPE_LSR, val), ctx);
+ emit(ARM_ORR_SI(rd[1], tmp2[1], rd[0], SRTYPE_ASL, 32 - val), ctx);
+ emit(ARM_MOV_SI(rd[0], rd[0], SRTYPE_ASR, val), ctx);
+ } else if (val == 32) {
+ emit(ARM_MOV_R(rd[1], rd[0]), ctx);
+ emit(ARM_MOV_SI(rd[0], rd[0], SRTYPE_ASR, 31), ctx);
+ } else {
+ emit(ARM_MOV_SI(rd[1], rd[0], SRTYPE_ASR, val - 32), ctx);
+ emit(ARM_MOV_SI(rd[0], rd[0], SRTYPE_ASR, 31), ctx);
+ }
+
+ arm_bpf_put_reg64(dst, rd, ctx);
+}
+
+static inline void emit_a32_mul_r64(const s8 dst[], const s8 src[],
+ struct jit_ctx *ctx) {
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ const s8 *tmp2 = bpf2a32[TMP_REG_2];
+ const s8 *rd, *rt;
+
+ /* Setup operands for multiplication */
+ rd = arm_bpf_get_reg64(dst, tmp, ctx);
+ rt = arm_bpf_get_reg64(src, tmp2, ctx);
+
+ /* Do Multiplication */
+ emit(ARM_MUL(ARM_IP, rd[1], rt[0]), ctx);
+ emit(ARM_MUL(ARM_LR, rd[0], rt[1]), ctx);
+ emit(ARM_ADD_R(ARM_LR, ARM_IP, ARM_LR), ctx);
+
+ emit(ARM_UMULL(ARM_IP, rd[0], rd[1], rt[1]), ctx);
+ emit(ARM_ADD_R(rd[0], ARM_LR, rd[0]), ctx);
+
+ arm_bpf_put_reg32(dst_lo, ARM_IP, ctx);
+ arm_bpf_put_reg32(dst_hi, rd[0], ctx);
+}
+
+static bool is_ldst_imm(s16 off, const u8 size)
+{
+ s16 off_max = 0;
+
+ switch (size) {
+ case BPF_B:
+ case BPF_W:
+ off_max = 0xfff;
+ break;
+ case BPF_H:
+ off_max = 0xff;
+ break;
+ case BPF_DW:
+ /* Need to make sure off+4 does not overflow. */
+ off_max = 0xfff - 4;
+ break;
+ }
+ return -off_max <= off && off <= off_max;
+}
+
+static bool is_ldst_imm8(s16 off, const u8 size)
+{
+ s16 off_max = 0;
+
+ switch (size) {
+ case BPF_B:
+ off_max = 0xff;
+ break;
+ case BPF_W:
+ off_max = 0xfff;
+ break;
+ case BPF_H:
+ off_max = 0xff;
+ break;
+ }
+ return -off_max <= off && off <= off_max;
+}
+
+/* *(size *)(dst + off) = src */
+static inline void emit_str_r(const s8 dst, const s8 src[],
+ s16 off, struct jit_ctx *ctx, const u8 sz){
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ s8 rd;
+
+ rd = arm_bpf_get_reg32(dst, tmp[1], ctx);
+
+ if (!is_ldst_imm(off, sz)) {
+ emit_a32_mov_i(tmp[0], off, ctx);
+ emit(ARM_ADD_R(tmp[0], tmp[0], rd), ctx);
+ rd = tmp[0];
+ off = 0;
+ }
+ switch (sz) {
+ case BPF_B:
+ /* Store a Byte */
+ emit(ARM_STRB_I(src_lo, rd, off), ctx);
+ break;
+ case BPF_H:
+ /* Store a HalfWord */
+ emit(ARM_STRH_I(src_lo, rd, off), ctx);
+ break;
+ case BPF_W:
+ /* Store a Word */
+ emit(ARM_STR_I(src_lo, rd, off), ctx);
+ break;
+ case BPF_DW:
+ /* Store a Double Word */
+ emit(ARM_STR_I(src_lo, rd, off), ctx);
+ emit(ARM_STR_I(src_hi, rd, off + 4), ctx);
+ break;
+ }
+}
+
+/* dst = *(size*)(src + off) */
+static inline void emit_ldx_r(const s8 dst[], const s8 src,
+ s16 off, struct jit_ctx *ctx, const u8 sz){
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ const s8 *rd = is_stacked(dst_lo) ? tmp : dst;
+ s8 rm = src;
+
+ if (!is_ldst_imm(off, sz)) {
+ emit_a32_mov_i(tmp[0], off, ctx);
+ emit(ARM_ADD_R(tmp[0], tmp[0], src), ctx);
+ rm = tmp[0];
+ off = 0;
+ } else if (rd[1] == rm) {
+ emit(ARM_MOV_R(tmp[0], rm), ctx);
+ rm = tmp[0];
+ }
+ switch (sz) {
+ case BPF_B:
+ /* Load a Byte */
+ emit(ARM_LDRB_I(rd[1], rm, off), ctx);
+ if (!ctx->prog->aux->verifier_zext)
+ emit_a32_mov_i(rd[0], 0, ctx);
+ break;
+ case BPF_H:
+ /* Load a HalfWord */
+ emit(ARM_LDRH_I(rd[1], rm, off), ctx);
+ if (!ctx->prog->aux->verifier_zext)
+ emit_a32_mov_i(rd[0], 0, ctx);
+ break;
+ case BPF_W:
+ /* Load a Word */
+ emit(ARM_LDR_I(rd[1], rm, off), ctx);
+ if (!ctx->prog->aux->verifier_zext)
+ emit_a32_mov_i(rd[0], 0, ctx);
+ break;
+ case BPF_DW:
+ /* Load a Double Word */
+ emit(ARM_LDR_I(rd[1], rm, off), ctx);
+ emit(ARM_LDR_I(rd[0], rm, off + 4), ctx);
+ break;
+ }
+ arm_bpf_put_reg64(dst, rd, ctx);
+}
+
+/* dst = *(signed size*)(src + off) */
+static inline void emit_ldsx_r(const s8 dst[], const s8 src,
+ s16 off, struct jit_ctx *ctx, const u8 sz){
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ const s8 *rd = is_stacked(dst_lo) ? tmp : dst;
+ s8 rm = src;
+ int add_off;
+
+ if (!is_ldst_imm8(off, sz)) {
+ /*
+ * offset does not fit in the load/store immediate,
+ * construct an ADD instruction to apply the offset.
+ */
+ add_off = imm8m(off);
+ if (add_off > 0) {
+ emit(ARM_ADD_I(tmp[0], src, add_off), ctx);
+ rm = tmp[0];
+ } else {
+ emit_a32_mov_i(tmp[0], off, ctx);
+ emit(ARM_ADD_R(tmp[0], tmp[0], src), ctx);
+ rm = tmp[0];
+ }
+ off = 0;
+ }
+
+ switch (sz) {
+ case BPF_B:
+ /* Load a Byte with sign extension*/
+ emit(ARM_LDRSB_I(rd[1], rm, off), ctx);
+ break;
+ case BPF_H:
+ /* Load a HalfWord with sign extension*/
+ emit(ARM_LDRSH_I(rd[1], rm, off), ctx);
+ break;
+ case BPF_W:
+ /* Load a Word*/
+ emit(ARM_LDR_I(rd[1], rm, off), ctx);
+ break;
+ }
+ /* Carry the sign extension to upper 32 bits */
+ emit(ARM_ASR_I(rd[0], rd[1], 31), ctx);
+ arm_bpf_put_reg64(dst, rd, ctx);
+}
+
+/* Arithmatic Operation */
+static inline void emit_ar_r(const u8 rd, const u8 rt, const u8 rm,
+ const u8 rn, struct jit_ctx *ctx, u8 op,
+ bool is_jmp64) {
+ switch (op) {
+ case BPF_JSET:
+ if (is_jmp64) {
+ emit(ARM_AND_R(ARM_IP, rt, rn), ctx);
+ emit(ARM_AND_R(ARM_LR, rd, rm), ctx);
+ emit(ARM_ORRS_R(ARM_IP, ARM_LR, ARM_IP), ctx);
+ } else {
+ emit(ARM_ANDS_R(ARM_IP, rt, rn), ctx);
+ }
+ break;
+ case BPF_JEQ:
+ case BPF_JNE:
+ case BPF_JGT:
+ case BPF_JGE:
+ case BPF_JLE:
+ case BPF_JLT:
+ if (is_jmp64) {
+ emit(ARM_CMP_R(rd, rm), ctx);
+ /* Only compare low halve if high halve are equal. */
+ _emit(ARM_COND_EQ, ARM_CMP_R(rt, rn), ctx);
+ } else {
+ emit(ARM_CMP_R(rt, rn), ctx);
+ }
+ break;
+ case BPF_JSLE:
+ case BPF_JSGT:
+ emit(ARM_CMP_R(rn, rt), ctx);
+ if (is_jmp64)
+ emit(ARM_SBCS_R(ARM_IP, rm, rd), ctx);
+ break;
+ case BPF_JSLT:
+ case BPF_JSGE:
+ emit(ARM_CMP_R(rt, rn), ctx);
+ if (is_jmp64)
+ emit(ARM_SBCS_R(ARM_IP, rd, rm), ctx);
+ break;
+ }
+}
+
+static int out_offset = -1; /* initialized on the first pass of build_body() */
+static int emit_bpf_tail_call(struct jit_ctx *ctx)
+{
+
+ /* bpf_tail_call(void *prog_ctx, struct bpf_array *array, u64 index) */
+ const s8 *r2 = bpf2a32[BPF_REG_2];
+ const s8 *r3 = bpf2a32[BPF_REG_3];
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ const s8 *tmp2 = bpf2a32[TMP_REG_2];
+ const s8 *tcc = bpf2a32[TCALL_CNT];
+ const s8 *tc;
+ const int idx0 = ctx->idx;
+#define cur_offset (ctx->idx - idx0)
+#define jmp_offset (out_offset - (cur_offset) - 2)
+ u32 lo, hi;
+ s8 r_array, r_index;
+ int off;
+
+ /* if (index >= array->map.max_entries)
+ * goto out;
+ */
+ BUILD_BUG_ON(offsetof(struct bpf_array, map.max_entries) >
+ ARM_INST_LDST__IMM12);
+ off = offsetof(struct bpf_array, map.max_entries);
+ r_array = arm_bpf_get_reg32(r2[1], tmp2[0], ctx);
+ /* index is 32-bit for arrays */
+ r_index = arm_bpf_get_reg32(r3[1], tmp2[1], ctx);
+ /* array->map.max_entries */
+ emit(ARM_LDR_I(tmp[1], r_array, off), ctx);
+ /* index >= array->map.max_entries */
+ emit(ARM_CMP_R(r_index, tmp[1]), ctx);
+ _emit(ARM_COND_CS, ARM_B(jmp_offset), ctx);
+
+ /* tmp2[0] = array, tmp2[1] = index */
+
+ /*
+ * if (tail_call_cnt >= MAX_TAIL_CALL_CNT)
+ * goto out;
+ * tail_call_cnt++;
+ */
+ lo = (u32)MAX_TAIL_CALL_CNT;
+ hi = (u32)((u64)MAX_TAIL_CALL_CNT >> 32);
+ tc = arm_bpf_get_reg64(tcc, tmp, ctx);
+ emit(ARM_CMP_I(tc[0], hi), ctx);
+ _emit(ARM_COND_EQ, ARM_CMP_I(tc[1], lo), ctx);
+ _emit(ARM_COND_CS, ARM_B(jmp_offset), ctx);
+ emit(ARM_ADDS_I(tc[1], tc[1], 1), ctx);
+ emit(ARM_ADC_I(tc[0], tc[0], 0), ctx);
+ arm_bpf_put_reg64(tcc, tmp, ctx);
+
+ /* prog = array->ptrs[index]
+ * if (prog == NULL)
+ * goto out;
+ */
+ BUILD_BUG_ON(imm8m(offsetof(struct bpf_array, ptrs)) < 0);
+ off = imm8m(offsetof(struct bpf_array, ptrs));
+ emit(ARM_ADD_I(tmp[1], r_array, off), ctx);
+ emit(ARM_LDR_R_SI(tmp[1], tmp[1], r_index, SRTYPE_ASL, 2), ctx);
+ emit(ARM_CMP_I(tmp[1], 0), ctx);
+ _emit(ARM_COND_EQ, ARM_B(jmp_offset), ctx);
+
+ /* goto *(prog->bpf_func + prologue_size); */
+ BUILD_BUG_ON(offsetof(struct bpf_prog, bpf_func) >
+ ARM_INST_LDST__IMM12);
+ off = offsetof(struct bpf_prog, bpf_func);
+ emit(ARM_LDR_I(tmp[1], tmp[1], off), ctx);
+ emit(ARM_ADD_I(tmp[1], tmp[1], ctx->prologue_bytes), ctx);
+ emit_bx_r(tmp[1], ctx);
+
+ /* out: */
+ if (out_offset == -1)
+ out_offset = cur_offset;
+ if (cur_offset != out_offset) {
+ pr_err_once("tail_call out_offset = %d, expected %d!\n",
+ cur_offset, out_offset);
+ return -1;
+ }
+ return 0;
+#undef cur_offset
+#undef jmp_offset
+}
+
+/* 0xabcd => 0xcdab */
+static inline void emit_rev16(const u8 rd, const u8 rn, struct jit_ctx *ctx)
+{
+#if __LINUX_ARM_ARCH__ < 6
+ const s8 *tmp2 = bpf2a32[TMP_REG_2];
+
+ emit(ARM_AND_I(tmp2[1], rn, 0xff), ctx);
+ emit(ARM_MOV_SI(tmp2[0], rn, SRTYPE_LSR, 8), ctx);
+ emit(ARM_AND_I(tmp2[0], tmp2[0], 0xff), ctx);
+ emit(ARM_ORR_SI(rd, tmp2[0], tmp2[1], SRTYPE_LSL, 8), ctx);
+#else /* ARMv6+ */
+ emit(ARM_REV16(rd, rn), ctx);
+#endif
+}
+
+/* 0xabcdefgh => 0xghefcdab */
+static inline void emit_rev32(const u8 rd, const u8 rn, struct jit_ctx *ctx)
+{
+#if __LINUX_ARM_ARCH__ < 6
+ const s8 *tmp2 = bpf2a32[TMP_REG_2];
+
+ emit(ARM_AND_I(tmp2[1], rn, 0xff), ctx);
+ emit(ARM_MOV_SI(tmp2[0], rn, SRTYPE_LSR, 24), ctx);
+ emit(ARM_ORR_SI(ARM_IP, tmp2[0], tmp2[1], SRTYPE_LSL, 24), ctx);
+
+ emit(ARM_MOV_SI(tmp2[1], rn, SRTYPE_LSR, 8), ctx);
+ emit(ARM_AND_I(tmp2[1], tmp2[1], 0xff), ctx);
+ emit(ARM_MOV_SI(tmp2[0], rn, SRTYPE_LSR, 16), ctx);
+ emit(ARM_AND_I(tmp2[0], tmp2[0], 0xff), ctx);
+ emit(ARM_MOV_SI(tmp2[0], tmp2[0], SRTYPE_LSL, 8), ctx);
+ emit(ARM_ORR_SI(tmp2[0], tmp2[0], tmp2[1], SRTYPE_LSL, 16), ctx);
+ emit(ARM_ORR_R(rd, ARM_IP, tmp2[0]), ctx);
+
+#else /* ARMv6+ */
+ emit(ARM_REV(rd, rn), ctx);
+#endif
+}
+
+// push the scratch stack register on top of the stack
+static inline void emit_push_r64(const s8 src[], struct jit_ctx *ctx)
+{
+ const s8 *tmp2 = bpf2a32[TMP_REG_2];
+ const s8 *rt;
+ u16 reg_set = 0;
+
+ rt = arm_bpf_get_reg64(src, tmp2, ctx);
+
+ reg_set = (1 << rt[1]) | (1 << rt[0]);
+ emit(ARM_PUSH(reg_set), ctx);
+}
+
+static void build_prologue(struct jit_ctx *ctx)
+{
+ const s8 arm_r0 = bpf2a32[BPF_REG_0][1];
+ const s8 *bpf_r1 = bpf2a32[BPF_REG_1];
+ const s8 *bpf_fp = bpf2a32[BPF_REG_FP];
+ const s8 *tcc = bpf2a32[TCALL_CNT];
+
+ /* Save callee saved registers. */
+#ifdef CONFIG_FRAME_POINTER
+ u16 reg_set = CALLEE_PUSH_MASK | 1 << ARM_IP | 1 << ARM_PC;
+ emit(ARM_MOV_R(ARM_IP, ARM_SP), ctx);
+ emit(ARM_PUSH(reg_set), ctx);
+ emit(ARM_SUB_I(ARM_FP, ARM_IP, 4), ctx);
+#else
+ emit(ARM_PUSH(CALLEE_PUSH_MASK), ctx);
+ emit(ARM_MOV_R(ARM_FP, ARM_SP), ctx);
+#endif
+ /* mov r3, #0 */
+ /* sub r2, sp, #SCRATCH_SIZE */
+ emit(ARM_MOV_I(bpf_r1[0], 0), ctx);
+ emit(ARM_SUB_I(bpf_r1[1], ARM_SP, SCRATCH_SIZE), ctx);
+
+ ctx->stack_size = imm8m(STACK_SIZE);
+
+ /* Set up function call stack */
+ emit(ARM_SUB_I(ARM_SP, ARM_SP, ctx->stack_size), ctx);
+
+ /* Set up BPF prog stack base register */
+ emit_a32_mov_r64(true, bpf_fp, bpf_r1, ctx);
+
+ /* Initialize Tail Count */
+ emit(ARM_MOV_I(bpf_r1[1], 0), ctx);
+ emit_a32_mov_r64(true, tcc, bpf_r1, ctx);
+
+ /* Move BPF_CTX to BPF_R1 */
+ emit(ARM_MOV_R(bpf_r1[1], arm_r0), ctx);
+
+ /* end of prologue */
+}
+
+/* restore callee saved registers. */
+static void build_epilogue(struct jit_ctx *ctx)
+{
+#ifdef CONFIG_FRAME_POINTER
+ /* When using frame pointers, some additional registers need to
+ * be loaded. */
+ u16 reg_set = CALLEE_POP_MASK | 1 << ARM_SP;
+ emit(ARM_SUB_I(ARM_SP, ARM_FP, hweight16(reg_set) * 4), ctx);
+ emit(ARM_LDM(ARM_SP, reg_set), ctx);
+#else
+ /* Restore callee saved registers. */
+ emit(ARM_MOV_R(ARM_SP, ARM_FP), ctx);
+ emit(ARM_POP(CALLEE_POP_MASK), ctx);
+#endif
+}
+
+/*
+ * Convert an eBPF instruction to native instruction, i.e
+ * JITs an eBPF instruction.
+ * Returns :
+ * 0 - Successfully JITed an 8-byte eBPF instruction
+ * >0 - Successfully JITed a 16-byte eBPF instruction
+ * <0 - Failed to JIT.
+ */
+static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
+{
+ const u8 code = insn->code;
+ const s8 *dst = bpf2a32[insn->dst_reg];
+ const s8 *src = bpf2a32[insn->src_reg];
+ const s8 *tmp = bpf2a32[TMP_REG_1];
+ const s8 *tmp2 = bpf2a32[TMP_REG_2];
+ const s16 off = insn->off;
+ const s32 imm = insn->imm;
+ const int i = insn - ctx->prog->insnsi;
+ const bool is64 = BPF_CLASS(code) == BPF_ALU64;
+ const s8 *rd, *rs;
+ s8 rd_lo, rt, rm, rn;
+ s32 jmp_offset;
+
+#define check_imm(bits, imm) do { \
+ if ((imm) >= (1 << ((bits) - 1)) || \
+ (imm) < -(1 << ((bits) - 1))) { \
+ pr_info("[%2d] imm=%d(0x%x) out of range\n", \
+ i, imm, imm); \
+ return -EINVAL; \
+ } \
+} while (0)
+#define check_imm24(imm) check_imm(24, imm)
+
+ switch (code) {
+ /* ALU operations */
+
+ /* dst = src */
+ case BPF_ALU | BPF_MOV | BPF_K:
+ case BPF_ALU | BPF_MOV | BPF_X:
+ case BPF_ALU64 | BPF_MOV | BPF_K:
+ case BPF_ALU64 | BPF_MOV | BPF_X:
+ switch (BPF_SRC(code)) {
+ case BPF_X:
+ if (imm == 1) {
+ /* Special mov32 for zext */
+ emit_a32_mov_i(dst_hi, 0, ctx);
+ break;
+ }
+ if (insn->off)
+ emit_a32_movsx_r64(is64, insn->off, dst, src, ctx);
+ else
+ emit_a32_mov_r64(is64, dst, src, ctx);
+ break;
+ case BPF_K:
+ /* Sign-extend immediate value to destination reg */
+ emit_a32_mov_se_i64(is64, dst, imm, ctx);
+ break;
+ }
+ break;
+ /* dst = dst + src/imm */
+ /* dst = dst - src/imm */
+ /* dst = dst | src/imm */
+ /* dst = dst & src/imm */
+ /* dst = dst ^ src/imm */
+ /* dst = dst * src/imm */
+ /* dst = dst << src */
+ /* dst = dst >> src */
+ case BPF_ALU | BPF_ADD | BPF_K:
+ case BPF_ALU | BPF_ADD | BPF_X:
+ case BPF_ALU | BPF_SUB | BPF_K:
+ case BPF_ALU | BPF_SUB | BPF_X:
+ case BPF_ALU | BPF_OR | BPF_K:
+ case BPF_ALU | BPF_OR | BPF_X:
+ case BPF_ALU | BPF_AND | BPF_K:
+ case BPF_ALU | BPF_AND | BPF_X:
+ case BPF_ALU | BPF_XOR | BPF_K:
+ case BPF_ALU | BPF_XOR | BPF_X:
+ case BPF_ALU | BPF_MUL | BPF_K:
+ case BPF_ALU | BPF_MUL | BPF_X:
+ case BPF_ALU | BPF_LSH | BPF_X:
+ case BPF_ALU | BPF_RSH | BPF_X:
+ case BPF_ALU | BPF_ARSH | BPF_X:
+ case BPF_ALU64 | BPF_ADD | BPF_K:
+ case BPF_ALU64 | BPF_ADD | BPF_X:
+ case BPF_ALU64 | BPF_SUB | BPF_K:
+ case BPF_ALU64 | BPF_SUB | BPF_X:
+ case BPF_ALU64 | BPF_OR | BPF_K:
+ case BPF_ALU64 | BPF_OR | BPF_X:
+ case BPF_ALU64 | BPF_AND | BPF_K:
+ case BPF_ALU64 | BPF_AND | BPF_X:
+ case BPF_ALU64 | BPF_XOR | BPF_K:
+ case BPF_ALU64 | BPF_XOR | BPF_X:
+ switch (BPF_SRC(code)) {
+ case BPF_X:
+ emit_a32_alu_r64(is64, dst, src, ctx, BPF_OP(code));
+ break;
+ case BPF_K:
+ /* Move immediate value to the temporary register
+ * and then do the ALU operation on the temporary
+ * register as this will sign-extend the immediate
+ * value into temporary reg and then it would be
+ * safe to do the operation on it.
+ */
+ emit_a32_mov_se_i64(is64, tmp2, imm, ctx);
+ emit_a32_alu_r64(is64, dst, tmp2, ctx, BPF_OP(code));
+ break;
+ }
+ break;
+ /* dst = dst / src(imm) */
+ /* dst = dst % src(imm) */
+ case BPF_ALU | BPF_DIV | BPF_K:
+ case BPF_ALU | BPF_DIV | BPF_X:
+ case BPF_ALU | BPF_MOD | BPF_K:
+ case BPF_ALU | BPF_MOD | BPF_X:
+ rd_lo = arm_bpf_get_reg32(dst_lo, tmp2[1], ctx);
+ switch (BPF_SRC(code)) {
+ case BPF_X:
+ rt = arm_bpf_get_reg32(src_lo, tmp2[0], ctx);
+ break;
+ case BPF_K:
+ rt = tmp2[0];
+ emit_a32_mov_i(rt, imm, ctx);
+ break;
+ default:
+ rt = src_lo;
+ break;
+ }
+ emit_udivmod(rd_lo, rd_lo, rt, ctx, BPF_OP(code), off);
+ arm_bpf_put_reg32(dst_lo, rd_lo, ctx);
+ if (!ctx->prog->aux->verifier_zext)
+ emit_a32_mov_i(dst_hi, 0, ctx);
+ break;
+ case BPF_ALU64 | BPF_DIV | BPF_K:
+ case BPF_ALU64 | BPF_DIV | BPF_X:
+ case BPF_ALU64 | BPF_MOD | BPF_K:
+ case BPF_ALU64 | BPF_MOD | BPF_X:
+ rd = arm_bpf_get_reg64(dst, tmp2, ctx);
+ switch (BPF_SRC(code)) {
+ case BPF_X:
+ rs = arm_bpf_get_reg64(src, tmp, ctx);
+ break;
+ case BPF_K:
+ rs = tmp;
+ emit_a32_mov_se_i64(is64, rs, imm, ctx);
+ break;
+ }
+ emit_udivmod64(rd, rd, rs, ctx, BPF_OP(code), off);
+ arm_bpf_put_reg64(dst, rd, ctx);
+ break;
+ /* dst = dst << imm */
+ /* dst = dst >> imm */
+ /* dst = dst >> imm (signed) */
+ case BPF_ALU | BPF_LSH | BPF_K:
+ case BPF_ALU | BPF_RSH | BPF_K:
+ case BPF_ALU | BPF_ARSH | BPF_K:
+ if (unlikely(imm > 31))
+ return -EINVAL;
+ if (imm)
+ emit_a32_alu_i(dst_lo, imm, ctx, BPF_OP(code));
+ if (!ctx->prog->aux->verifier_zext)
+ emit_a32_mov_i(dst_hi, 0, ctx);
+ break;
+ /* dst = dst << imm */
+ case BPF_ALU64 | BPF_LSH | BPF_K:
+ if (unlikely(imm > 63))
+ return -EINVAL;
+ emit_a32_lsh_i64(dst, imm, ctx);
+ break;
+ /* dst = dst >> imm */
+ case BPF_ALU64 | BPF_RSH | BPF_K:
+ if (unlikely(imm > 63))
+ return -EINVAL;
+ emit_a32_rsh_i64(dst, imm, ctx);
+ break;
+ /* dst = dst << src */
+ case BPF_ALU64 | BPF_LSH | BPF_X:
+ emit_a32_lsh_r64(dst, src, ctx);
+ break;
+ /* dst = dst >> src */
+ case BPF_ALU64 | BPF_RSH | BPF_X:
+ emit_a32_rsh_r64(dst, src, ctx);
+ break;
+ /* dst = dst >> src (signed) */
+ case BPF_ALU64 | BPF_ARSH | BPF_X:
+ emit_a32_arsh_r64(dst, src, ctx);
+ break;
+ /* dst = dst >> imm (signed) */
+ case BPF_ALU64 | BPF_ARSH | BPF_K:
+ if (unlikely(imm > 63))
+ return -EINVAL;
+ emit_a32_arsh_i64(dst, imm, ctx);
+ break;
+ /* dst = ~dst */
+ case BPF_ALU | BPF_NEG:
+ emit_a32_alu_i(dst_lo, 0, ctx, BPF_OP(code));
+ if (!ctx->prog->aux->verifier_zext)
+ emit_a32_mov_i(dst_hi, 0, ctx);
+ break;
+ /* dst = ~dst (64 bit) */
+ case BPF_ALU64 | BPF_NEG:
+ emit_a32_neg64(dst, ctx);
+ break;
+ /* dst = dst * src/imm */
+ case BPF_ALU64 | BPF_MUL | BPF_X:
+ case BPF_ALU64 | BPF_MUL | BPF_K:
+ switch (BPF_SRC(code)) {
+ case BPF_X:
+ emit_a32_mul_r64(dst, src, ctx);
+ break;
+ case BPF_K:
+ /* Move immediate value to the temporary register
+ * and then do the multiplication on it as this
+ * will sign-extend the immediate value into temp
+ * reg then it would be safe to do the operation
+ * on it.
+ */
+ emit_a32_mov_se_i64(is64, tmp2, imm, ctx);
+ emit_a32_mul_r64(dst, tmp2, ctx);
+ break;
+ }
+ break;
+ /* dst = htole(dst) */
+ /* dst = htobe(dst) */
+ case BPF_ALU | BPF_END | BPF_FROM_LE: /* also BPF_TO_LE */
+ case BPF_ALU | BPF_END | BPF_FROM_BE: /* also BPF_TO_BE */
+ /* dst = bswap(dst) */
+ case BPF_ALU64 | BPF_END | BPF_FROM_LE: /* also BPF_TO_LE */
+ rd = arm_bpf_get_reg64(dst, tmp, ctx);
+ if (BPF_SRC(code) == BPF_FROM_LE && BPF_CLASS(code) != BPF_ALU64)
+ goto emit_bswap_uxt;
+ switch (imm) {
+ case 16:
+ emit_rev16(rd[1], rd[1], ctx);
+ goto emit_bswap_uxt;
+ case 32:
+ emit_rev32(rd[1], rd[1], ctx);
+ goto emit_bswap_uxt;
+ case 64:
+ emit_rev32(ARM_LR, rd[1], ctx);
+ emit_rev32(rd[1], rd[0], ctx);
+ emit(ARM_MOV_R(rd[0], ARM_LR), ctx);
+ break;
+ }
+ goto exit;
+emit_bswap_uxt:
+ switch (imm) {
+ case 16:
+ /* zero-extend 16 bits into 64 bits */
+#if __LINUX_ARM_ARCH__ < 6
+ emit_a32_mov_i(tmp2[1], 0xffff, ctx);
+ emit(ARM_AND_R(rd[1], rd[1], tmp2[1]), ctx);
+#else /* ARMv6+ */
+ emit(ARM_UXTH(rd[1], rd[1]), ctx);
+#endif
+ if (!ctx->prog->aux->verifier_zext)
+ emit(ARM_EOR_R(rd[0], rd[0], rd[0]), ctx);
+ break;
+ case 32:
+ /* zero-extend 32 bits into 64 bits */
+ if (!ctx->prog->aux->verifier_zext)
+ emit(ARM_EOR_R(rd[0], rd[0], rd[0]), ctx);
+ break;
+ case 64:
+ /* nop */
+ break;
+ }
+exit:
+ arm_bpf_put_reg64(dst, rd, ctx);
+ break;
+ /* dst = imm64 */
+ case BPF_LD | BPF_IMM | BPF_DW:
+ {
+ u64 val = (u32)imm | (u64)insn[1].imm << 32;
+
+ if (insn->src_reg == BPF_PSEUDO_FUNC)
+ goto notyet;
+
+ emit_a32_mov_i64(dst, val, ctx);
+
+ return 1;
+ }
+ /* LDX: dst = *(size *)(src + off) */
+ case BPF_LDX | BPF_MEM | BPF_W:
+ case BPF_LDX | BPF_MEM | BPF_H:
+ case BPF_LDX | BPF_MEM | BPF_B:
+ case BPF_LDX | BPF_MEM | BPF_DW:
+ /* LDSX: dst = *(signed size *)(src + off) */
+ case BPF_LDX | BPF_MEMSX | BPF_B:
+ case BPF_LDX | BPF_MEMSX | BPF_H:
+ case BPF_LDX | BPF_MEMSX | BPF_W:
+ rn = arm_bpf_get_reg32(src_lo, tmp2[1], ctx);
+ if (BPF_MODE(insn->code) == BPF_MEMSX)
+ emit_ldsx_r(dst, rn, off, ctx, BPF_SIZE(code));
+ else
+ emit_ldx_r(dst, rn, off, ctx, BPF_SIZE(code));
+ break;
+ /* speculation barrier */
+ case BPF_ST | BPF_NOSPEC:
+ break;
+ /* ST: *(size *)(dst + off) = imm */
+ case BPF_ST | BPF_MEM | BPF_W:
+ case BPF_ST | BPF_MEM | BPF_H:
+ case BPF_ST | BPF_MEM | BPF_B:
+ case BPF_ST | BPF_MEM | BPF_DW:
+ switch (BPF_SIZE(code)) {
+ case BPF_DW:
+ /* Sign-extend immediate value into temp reg */
+ emit_a32_mov_se_i64(true, tmp2, imm, ctx);
+ break;
+ case BPF_W:
+ case BPF_H:
+ case BPF_B:
+ emit_a32_mov_i(tmp2[1], imm, ctx);
+ break;
+ }
+ emit_str_r(dst_lo, tmp2, off, ctx, BPF_SIZE(code));
+ break;
+ /* Atomic ops */
+ case BPF_STX | BPF_ATOMIC | BPF_W:
+ case BPF_STX | BPF_ATOMIC | BPF_DW:
+ goto notyet;
+ /* STX: *(size *)(dst + off) = src */
+ case BPF_STX | BPF_MEM | BPF_W:
+ case BPF_STX | BPF_MEM | BPF_H:
+ case BPF_STX | BPF_MEM | BPF_B:
+ case BPF_STX | BPF_MEM | BPF_DW:
+ rs = arm_bpf_get_reg64(src, tmp2, ctx);
+ emit_str_r(dst_lo, rs, off, ctx, BPF_SIZE(code));
+ break;
+ /* PC += off if dst == src */
+ /* PC += off if dst > src */
+ /* PC += off if dst >= src */
+ /* PC += off if dst < src */
+ /* PC += off if dst <= src */
+ /* PC += off if dst != src */
+ /* PC += off if dst > src (signed) */
+ /* PC += off if dst >= src (signed) */
+ /* PC += off if dst < src (signed) */
+ /* PC += off if dst <= src (signed) */
+ /* PC += off if dst & src */
+ case BPF_JMP | BPF_JEQ | BPF_X:
+ case BPF_JMP | BPF_JGT | BPF_X:
+ case BPF_JMP | BPF_JGE | BPF_X:
+ case BPF_JMP | BPF_JNE | BPF_X:
+ case BPF_JMP | BPF_JSGT | BPF_X:
+ case BPF_JMP | BPF_JSGE | BPF_X:
+ case BPF_JMP | BPF_JSET | BPF_X:
+ case BPF_JMP | BPF_JLE | BPF_X:
+ case BPF_JMP | BPF_JLT | BPF_X:
+ case BPF_JMP | BPF_JSLT | BPF_X:
+ case BPF_JMP | BPF_JSLE | BPF_X:
+ case BPF_JMP32 | BPF_JEQ | BPF_X:
+ case BPF_JMP32 | BPF_JGT | BPF_X:
+ case BPF_JMP32 | BPF_JGE | BPF_X:
+ case BPF_JMP32 | BPF_JNE | BPF_X:
+ case BPF_JMP32 | BPF_JSGT | BPF_X:
+ case BPF_JMP32 | BPF_JSGE | BPF_X:
+ case BPF_JMP32 | BPF_JSET | BPF_X:
+ case BPF_JMP32 | BPF_JLE | BPF_X:
+ case BPF_JMP32 | BPF_JLT | BPF_X:
+ case BPF_JMP32 | BPF_JSLT | BPF_X:
+ case BPF_JMP32 | BPF_JSLE | BPF_X:
+ /* Setup source registers */
+ rm = arm_bpf_get_reg32(src_hi, tmp2[0], ctx);
+ rn = arm_bpf_get_reg32(src_lo, tmp2[1], ctx);
+ goto go_jmp;
+ /* PC += off if dst == imm */
+ /* PC += off if dst > imm */
+ /* PC += off if dst >= imm */
+ /* PC += off if dst < imm */
+ /* PC += off if dst <= imm */
+ /* PC += off if dst != imm */
+ /* PC += off if dst > imm (signed) */
+ /* PC += off if dst >= imm (signed) */
+ /* PC += off if dst < imm (signed) */
+ /* PC += off if dst <= imm (signed) */
+ /* PC += off if dst & imm */
+ case BPF_JMP | BPF_JEQ | BPF_K:
+ case BPF_JMP | BPF_JGT | BPF_K:
+ case BPF_JMP | BPF_JGE | BPF_K:
+ case BPF_JMP | BPF_JNE | BPF_K:
+ case BPF_JMP | BPF_JSGT | BPF_K:
+ case BPF_JMP | BPF_JSGE | BPF_K:
+ case BPF_JMP | BPF_JSET | BPF_K:
+ case BPF_JMP | BPF_JLT | BPF_K:
+ case BPF_JMP | BPF_JLE | BPF_K:
+ case BPF_JMP | BPF_JSLT | BPF_K:
+ case BPF_JMP | BPF_JSLE | BPF_K:
+ case BPF_JMP32 | BPF_JEQ | BPF_K:
+ case BPF_JMP32 | BPF_JGT | BPF_K:
+ case BPF_JMP32 | BPF_JGE | BPF_K:
+ case BPF_JMP32 | BPF_JNE | BPF_K:
+ case BPF_JMP32 | BPF_JSGT | BPF_K:
+ case BPF_JMP32 | BPF_JSGE | BPF_K:
+ case BPF_JMP32 | BPF_JSET | BPF_K:
+ case BPF_JMP32 | BPF_JLT | BPF_K:
+ case BPF_JMP32 | BPF_JLE | BPF_K:
+ case BPF_JMP32 | BPF_JSLT | BPF_K:
+ case BPF_JMP32 | BPF_JSLE | BPF_K:
+ if (off == 0)
+ break;
+ rm = tmp2[0];
+ rn = tmp2[1];
+ /* Sign-extend immediate value */
+ emit_a32_mov_se_i64(true, tmp2, imm, ctx);
+go_jmp:
+ /* Setup destination register */
+ rd = arm_bpf_get_reg64(dst, tmp, ctx);
+
+ /* Check for the condition */
+ emit_ar_r(rd[0], rd[1], rm, rn, ctx, BPF_OP(code),
+ BPF_CLASS(code) == BPF_JMP);
+
+ /* Setup JUMP instruction */
+ jmp_offset = bpf2a32_offset(i+off, i, ctx);
+ switch (BPF_OP(code)) {
+ case BPF_JNE:
+ case BPF_JSET:
+ _emit(ARM_COND_NE, ARM_B(jmp_offset), ctx);
+ break;
+ case BPF_JEQ:
+ _emit(ARM_COND_EQ, ARM_B(jmp_offset), ctx);
+ break;
+ case BPF_JGT:
+ _emit(ARM_COND_HI, ARM_B(jmp_offset), ctx);
+ break;
+ case BPF_JGE:
+ _emit(ARM_COND_CS, ARM_B(jmp_offset), ctx);
+ break;
+ case BPF_JSGT:
+ _emit(ARM_COND_LT, ARM_B(jmp_offset), ctx);
+ break;
+ case BPF_JSGE:
+ _emit(ARM_COND_GE, ARM_B(jmp_offset), ctx);
+ break;
+ case BPF_JLE:
+ _emit(ARM_COND_LS, ARM_B(jmp_offset), ctx);
+ break;
+ case BPF_JLT:
+ _emit(ARM_COND_CC, ARM_B(jmp_offset), ctx);
+ break;
+ case BPF_JSLT:
+ _emit(ARM_COND_LT, ARM_B(jmp_offset), ctx);
+ break;
+ case BPF_JSLE:
+ _emit(ARM_COND_GE, ARM_B(jmp_offset), ctx);
+ break;
+ }
+ break;
+ /* JMP OFF */
+ case BPF_JMP | BPF_JA:
+ case BPF_JMP32 | BPF_JA:
+ {
+ if (BPF_CLASS(code) == BPF_JMP32 && imm != 0)
+ jmp_offset = bpf2a32_offset(i + imm, i, ctx);
+ else if (BPF_CLASS(code) == BPF_JMP && off != 0)
+ jmp_offset = bpf2a32_offset(i + off, i, ctx);
+ else
+ break;
+
+ check_imm24(jmp_offset);
+ emit(ARM_B(jmp_offset), ctx);
+ break;
+ }
+ /* tail call */
+ case BPF_JMP | BPF_TAIL_CALL:
+ if (emit_bpf_tail_call(ctx))
+ return -EFAULT;
+ break;
+ /* function call */
+ case BPF_JMP | BPF_CALL:
+ {
+ const s8 *r0 = bpf2a32[BPF_REG_0];
+ const s8 *r1 = bpf2a32[BPF_REG_1];
+ const s8 *r2 = bpf2a32[BPF_REG_2];
+ const s8 *r3 = bpf2a32[BPF_REG_3];
+ const s8 *r4 = bpf2a32[BPF_REG_4];
+ const s8 *r5 = bpf2a32[BPF_REG_5];
+ const u32 func = (u32)__bpf_call_base + (u32)imm;
+
+ if (insn->src_reg == BPF_PSEUDO_CALL)
+ goto notyet;
+
+ emit_a32_mov_r64(true, r0, r1, ctx);
+ emit_a32_mov_r64(true, r1, r2, ctx);
+ emit_push_r64(r5, ctx);
+ emit_push_r64(r4, ctx);
+ emit_push_r64(r3, ctx);
+
+ emit_a32_mov_i(tmp[1], func, ctx);
+ emit_blx_r(tmp[1], ctx);
+
+ emit(ARM_ADD_I(ARM_SP, ARM_SP, imm8m(24)), ctx); // callee clean
+ break;
+ }
+ /* function return */
+ case BPF_JMP | BPF_EXIT:
+ /* Optimization: when last instruction is EXIT
+ * simply fallthrough to epilogue.
+ */
+ if (i == ctx->prog->len - 1)
+ break;
+ jmp_offset = epilogue_offset(ctx);
+ check_imm24(jmp_offset);
+ emit(ARM_B(jmp_offset), ctx);
+ break;
+notyet:
+ pr_info_once("*** NOT YET: opcode %02x ***\n", code);
+ return -EFAULT;
+ default:
+ pr_err_once("unknown opcode %02x\n", code);
+ return -EINVAL;
+ }
+
+ if (ctx->flags & FLAG_IMM_OVERFLOW)
+ /*
+ * this instruction generated an overflow when
+ * trying to access the literal pool, so
+ * delegate this filter to the kernel interpreter.
+ */
+ return -1;
+ return 0;
+}
+
+static int build_body(struct jit_ctx *ctx)
+{
+ const struct bpf_prog *prog = ctx->prog;
+ unsigned int i;
+
+ for (i = 0; i < prog->len; i++) {
+ const struct bpf_insn *insn = &(prog->insnsi[i]);
+ int ret;
+
+ ret = build_insn(insn, ctx);
+
+ /* It's used with loading the 64 bit immediate value. */
+ if (ret > 0) {
+ i++;
+ if (ctx->target == NULL)
+ ctx->offsets[i] = ctx->idx;
+ continue;
+ }
+
+ if (ctx->target == NULL)
+ ctx->offsets[i] = ctx->idx;
+
+ /* If unsuccesful, return with error code */
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+static int validate_code(struct jit_ctx *ctx)
+{
+ int i;
+
+ for (i = 0; i < ctx->idx; i++) {
+ if (ctx->target[i] == __opcode_to_mem_arm(ARM_INST_UDF))
+ return -1;
+ }
+
+ return 0;
+}
+
+bool bpf_jit_needs_zext(void)
+{
+ return true;
+}
+
+struct bpf_prog *bpf_int_jit_compile(struct bpf_verifier_env *env, struct bpf_prog *prog)
+{
+ struct bpf_binary_header *header;
+ struct jit_ctx ctx;
+ unsigned int tmp_idx;
+ unsigned int image_size;
+ u8 *image_ptr;
+
+ /* If BPF JIT was not enabled then we must fall back to
+ * the interpreter.
+ */
+ if (!prog->jit_requested)
+ return prog;
+
+ memset(&ctx, 0, sizeof(ctx));
+ ctx.prog = prog;
+ ctx.cpu_architecture = cpu_architecture();
+
+ /* Not able to allocate memory for offsets[] , then
+ * we must fall back to the interpreter
+ */
+ ctx.offsets = kcalloc(prog->len, sizeof(int), GFP_KERNEL);
+ if (ctx.offsets == NULL)
+ return prog;
+
+ /* 1) fake pass to find in the length of the JITed code,
+ * to compute ctx->offsets and other context variables
+ * needed to compute final JITed code.
+ * Also, calculate random starting pointer/start of JITed code
+ * which is prefixed by random number of fault instructions.
+ *
+ * If the first pass fails then there is no chance of it
+ * being successful in the second pass, so just fall back
+ * to the interpreter.
+ */
+ if (build_body(&ctx))
+ goto out_off;
+
+ tmp_idx = ctx.idx;
+ build_prologue(&ctx);
+ ctx.prologue_bytes = (ctx.idx - tmp_idx) * 4;
+
+ ctx.epilogue_offset = ctx.idx;
+
+#if __LINUX_ARM_ARCH__ < 7
+ tmp_idx = ctx.idx;
+ build_epilogue(&ctx);
+ ctx.epilogue_bytes = (ctx.idx - tmp_idx) * 4;
+
+ ctx.idx += ctx.imm_count;
+ if (ctx.imm_count) {
+ ctx.imms = kcalloc(ctx.imm_count, sizeof(u32), GFP_KERNEL);
+ if (ctx.imms == NULL)
+ goto out_off;
+ }
+#else
+ /* there's nothing about the epilogue on ARMv7 */
+ build_epilogue(&ctx);
+#endif
+ /* Now we can get the actual image size of the JITed arm code.
+ * Currently, we are not considering the THUMB-2 instructions
+ * for jit, although it can decrease the size of the image.
+ *
+ * As each arm instruction is of length 32bit, we are translating
+ * number of JITed instructions into the size required to store these
+ * JITed code.
+ */
+ image_size = sizeof(u32) * ctx.idx;
+
+ /* Now we know the size of the structure to make */
+ header = bpf_jit_binary_alloc(image_size, &image_ptr,
+ sizeof(u32), jit_fill_hole);
+ /* Not able to allocate memory for the structure then
+ * we must fall back to the interpretation
+ */
+ if (header == NULL)
+ goto out_imms;
+
+ /* 2.) Actual pass to generate final JIT code */
+ ctx.target = (u32 *) image_ptr;
+ ctx.idx = 0;
+
+ build_prologue(&ctx);
+
+ /* If building the body of the JITed code fails somehow,
+ * we fall back to the interpretation.
+ */
+ if (build_body(&ctx) < 0)
+ goto out_free;
+ build_epilogue(&ctx);
+
+ /* 3.) Extra pass to validate JITed Code */
+ if (validate_code(&ctx))
+ goto out_free;
+ flush_icache_range((u32)header, (u32)(ctx.target + ctx.idx));
+
+ if (bpf_jit_enable > 1)
+ /* there are 2 passes here */
+ bpf_jit_dump(prog->len, image_size, 2, ctx.target);
+
+ if (bpf_jit_binary_lock_ro(header))
+ goto out_free;
+ prog->bpf_func = (void *)ctx.target;
+ prog->jited = 1;
+ prog->jited_len = image_size;
+
+out_imms:
+#if __LINUX_ARM_ARCH__ < 7
+ if (ctx.imm_count)
+ kfree(ctx.imms);
+#endif
+out_off:
+ kfree(ctx.offsets);
+
+ return prog;
+
+out_free:
+ image_ptr = NULL;
+ bpf_jit_binary_free(header);
+ goto out_imms;
+}
+
diff --git a/arch/arm/net/bpf_jit_32.h b/arch/arm/net/bpf_jit_32.h
new file mode 100644
index 000000000..438f0e1f9
--- /dev/null
+++ b/arch/arm/net/bpf_jit_32.h
@@ -0,0 +1,280 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Just-In-Time compiler for BPF filters on 32bit ARM
+ *
+ * Copyright (c) 2011 Mircea Gherzan <mgherzan@gmail.com>
+ */
+
+#ifndef PFILTER_OPCODES_ARM_H
+#define PFILTER_OPCODES_ARM_H
+
+/* ARM 32bit Registers */
+#define ARM_R0 0
+#define ARM_R1 1
+#define ARM_R2 2
+#define ARM_R3 3
+#define ARM_R4 4
+#define ARM_R5 5
+#define ARM_R6 6
+#define ARM_R7 7
+#define ARM_R8 8
+#define ARM_R9 9
+#define ARM_R10 10
+#define ARM_FP 11 /* Frame Pointer */
+#define ARM_IP 12 /* Intra-procedure scratch register */
+#define ARM_SP 13 /* Stack pointer: as load/store base reg */
+#define ARM_LR 14 /* Link Register */
+#define ARM_PC 15 /* Program counter */
+
+#define ARM_COND_EQ 0x0 /* == */
+#define ARM_COND_NE 0x1 /* != */
+#define ARM_COND_CS 0x2 /* unsigned >= */
+#define ARM_COND_HS ARM_COND_CS
+#define ARM_COND_CC 0x3 /* unsigned < */
+#define ARM_COND_LO ARM_COND_CC
+#define ARM_COND_MI 0x4 /* < 0 */
+#define ARM_COND_PL 0x5 /* >= 0 */
+#define ARM_COND_VS 0x6 /* Signed Overflow */
+#define ARM_COND_VC 0x7 /* No Signed Overflow */
+#define ARM_COND_HI 0x8 /* unsigned > */
+#define ARM_COND_LS 0x9 /* unsigned <= */
+#define ARM_COND_GE 0xa /* Signed >= */
+#define ARM_COND_LT 0xb /* Signed < */
+#define ARM_COND_GT 0xc /* Signed > */
+#define ARM_COND_LE 0xd /* Signed <= */
+#define ARM_COND_AL 0xe /* None */
+
+/* register shift types */
+#define SRTYPE_LSL 0
+#define SRTYPE_LSR 1
+#define SRTYPE_ASR 2
+#define SRTYPE_ROR 3
+#define SRTYPE_ASL (SRTYPE_LSL)
+
+#define ARM_INST_ADD_R 0x00800000
+#define ARM_INST_ADDS_R 0x00900000
+#define ARM_INST_ADC_R 0x00a00000
+#define ARM_INST_ADC_I 0x02a00000
+#define ARM_INST_ADD_I 0x02800000
+#define ARM_INST_ADDS_I 0x02900000
+
+#define ARM_INST_AND_R 0x00000000
+#define ARM_INST_ANDS_R 0x00100000
+#define ARM_INST_AND_I 0x02000000
+
+#define ARM_INST_BIC_R 0x01c00000
+#define ARM_INST_BIC_I 0x03c00000
+
+#define ARM_INST_B 0x0a000000
+#define ARM_INST_BX 0x012FFF10
+#define ARM_INST_BLX_R 0x012fff30
+
+#define ARM_INST_CMP_R 0x01500000
+#define ARM_INST_CMP_I 0x03500000
+
+#define ARM_INST_EOR_R 0x00200000
+#define ARM_INST_EOR_I 0x02200000
+
+#define ARM_INST_LDST__U 0x00800000
+#define ARM_INST_LDST__IMM12 0x00000fff
+#define ARM_INST_LDRB_I 0x05500000
+#define ARM_INST_LDRB_R 0x07d00000
+#define ARM_INST_LDRSB_I 0x015000d0
+#define ARM_INST_LDRD_I 0x014000d0
+#define ARM_INST_LDRH_I 0x015000b0
+#define ARM_INST_LDRH_R 0x019000b0
+#define ARM_INST_LDRSH_I 0x015000f0
+#define ARM_INST_LDR_I 0x05100000
+#define ARM_INST_LDR_R 0x07900000
+
+#define ARM_INST_LDM 0x08900000
+#define ARM_INST_LDM_IA 0x08b00000
+
+#define ARM_INST_LSL_I 0x01a00000
+#define ARM_INST_LSL_R 0x01a00010
+
+#define ARM_INST_LSR_I 0x01a00020
+#define ARM_INST_LSR_R 0x01a00030
+
+#define ARM_INST_ASR_I 0x01a00040
+#define ARM_INST_ASR_R 0x01a00050
+
+#define ARM_INST_MOV_R 0x01a00000
+#define ARM_INST_MOVS_R 0x01b00000
+#define ARM_INST_MOV_I 0x03a00000
+#define ARM_INST_MOVW 0x03000000
+#define ARM_INST_MOVT 0x03400000
+
+#define ARM_INST_MUL 0x00000090
+
+#define ARM_INST_POP 0x08bd0000
+#define ARM_INST_PUSH 0x092d0000
+
+#define ARM_INST_ORR_R 0x01800000
+#define ARM_INST_ORRS_R 0x01900000
+#define ARM_INST_ORR_I 0x03800000
+
+#define ARM_INST_REV 0x06bf0f30
+#define ARM_INST_REV16 0x06bf0fb0
+
+#define ARM_INST_RSB_I 0x02600000
+#define ARM_INST_RSBS_I 0x02700000
+#define ARM_INST_RSC_I 0x02e00000
+
+#define ARM_INST_SUB_R 0x00400000
+#define ARM_INST_SUBS_R 0x00500000
+#define ARM_INST_RSB_R 0x00600000
+#define ARM_INST_SUB_I 0x02400000
+#define ARM_INST_SUBS_I 0x02500000
+#define ARM_INST_SBC_I 0x02c00000
+#define ARM_INST_SBC_R 0x00c00000
+#define ARM_INST_SBCS_R 0x00d00000
+
+#define ARM_INST_STR_I 0x05000000
+#define ARM_INST_STRB_I 0x05400000
+#define ARM_INST_STRD_I 0x014000f0
+#define ARM_INST_STRH_I 0x014000b0
+
+#define ARM_INST_TST_R 0x01100000
+#define ARM_INST_TST_I 0x03100000
+
+#define ARM_INST_UDIV 0x0730f010
+#define ARM_INST_SDIV 0x0710f010
+
+#define ARM_INST_UMULL 0x00800090
+
+#define ARM_INST_MLS 0x00600090
+
+#define ARM_INST_UXTH 0x06ff0070
+
+/*
+ * Use a suitable undefined instruction to use for ARM/Thumb2 faulting.
+ * We need to be careful not to conflict with those used by other modules
+ * (BUG, kprobes, etc) and the register_undef_hook() system.
+ *
+ * The ARM architecture reference manual guarantees that the following
+ * instruction space will produce an undefined instruction exception on
+ * all CPUs:
+ *
+ * ARM: xxxx 0111 1111 xxxx xxxx xxxx 1111 xxxx ARMv7-AR, section A5.4
+ * Thumb: 1101 1110 xxxx xxxx ARMv7-M, section A5.2.6
+ */
+#define ARM_INST_UDF 0xe7fddef1
+
+/* register */
+#define _AL3_R(op, rd, rn, rm) ((op ## _R) | (rd) << 12 | (rn) << 16 | (rm))
+/* immediate */
+#define _AL3_I(op, rd, rn, imm) ((op ## _I) | (rd) << 12 | (rn) << 16 | (imm))
+/* register with register-shift */
+#define _AL3_SR(inst) (inst | (1 << 4))
+
+#define ARM_ADD_R(rd, rn, rm) _AL3_R(ARM_INST_ADD, rd, rn, rm)
+#define ARM_ADDS_R(rd, rn, rm) _AL3_R(ARM_INST_ADDS, rd, rn, rm)
+#define ARM_ADD_I(rd, rn, imm) _AL3_I(ARM_INST_ADD, rd, rn, imm)
+#define ARM_ADDS_I(rd, rn, imm) _AL3_I(ARM_INST_ADDS, rd, rn, imm)
+#define ARM_ADC_R(rd, rn, rm) _AL3_R(ARM_INST_ADC, rd, rn, rm)
+#define ARM_ADC_I(rd, rn, imm) _AL3_I(ARM_INST_ADC, rd, rn, imm)
+
+#define ARM_AND_R(rd, rn, rm) _AL3_R(ARM_INST_AND, rd, rn, rm)
+#define ARM_ANDS_R(rd, rn, rm) _AL3_R(ARM_INST_ANDS, rd, rn, rm)
+#define ARM_AND_I(rd, rn, imm) _AL3_I(ARM_INST_AND, rd, rn, imm)
+
+#define ARM_BIC_R(rd, rn, rm) _AL3_R(ARM_INST_BIC, rd, rn, rm)
+#define ARM_BIC_I(rd, rn, imm) _AL3_I(ARM_INST_BIC, rd, rn, imm)
+
+#define ARM_B(imm24) (ARM_INST_B | ((imm24) & 0xffffff))
+#define ARM_BX(rm) (ARM_INST_BX | (rm))
+#define ARM_BLX_R(rm) (ARM_INST_BLX_R | (rm))
+
+#define ARM_CMP_R(rn, rm) _AL3_R(ARM_INST_CMP, 0, rn, rm)
+#define ARM_CMP_I(rn, imm) _AL3_I(ARM_INST_CMP, 0, rn, imm)
+
+#define ARM_EOR_R(rd, rn, rm) _AL3_R(ARM_INST_EOR, rd, rn, rm)
+#define ARM_EOR_I(rd, rn, imm) _AL3_I(ARM_INST_EOR, rd, rn, imm)
+
+#define ARM_LDR_R(rt, rn, rm) (ARM_INST_LDR_R | ARM_INST_LDST__U \
+ | (rt) << 12 | (rn) << 16 \
+ | (rm))
+#define ARM_LDR_R_SI(rt, rn, rm, type, imm) \
+ (ARM_INST_LDR_R | ARM_INST_LDST__U \
+ | (rt) << 12 | (rn) << 16 \
+ | (imm) << 7 | (type) << 5 | (rm))
+#define ARM_LDRB_R(rt, rn, rm) (ARM_INST_LDRB_R | ARM_INST_LDST__U \
+ | (rt) << 12 | (rn) << 16 \
+ | (rm))
+#define ARM_LDRH_R(rt, rn, rm) (ARM_INST_LDRH_R | ARM_INST_LDST__U \
+ | (rt) << 12 | (rn) << 16 \
+ | (rm))
+
+#define ARM_LDM(rn, regs) (ARM_INST_LDM | (rn) << 16 | (regs))
+#define ARM_LDM_IA(rn, regs) (ARM_INST_LDM_IA | (rn) << 16 | (regs))
+
+#define ARM_LSL_R(rd, rn, rm) (_AL3_R(ARM_INST_LSL, rd, 0, rn) | (rm) << 8)
+#define ARM_LSL_I(rd, rn, imm) (_AL3_I(ARM_INST_LSL, rd, 0, rn) | (imm) << 7)
+
+#define ARM_LSR_R(rd, rn, rm) (_AL3_R(ARM_INST_LSR, rd, 0, rn) | (rm) << 8)
+#define ARM_LSR_I(rd, rn, imm) (_AL3_I(ARM_INST_LSR, rd, 0, rn) | (imm) << 7)
+#define ARM_ASR_R(rd, rn, rm) (_AL3_R(ARM_INST_ASR, rd, 0, rn) | (rm) << 8)
+#define ARM_ASR_I(rd, rn, imm) (_AL3_I(ARM_INST_ASR, rd, 0, rn) | (imm) << 7)
+
+#define ARM_MOV_R(rd, rm) _AL3_R(ARM_INST_MOV, rd, 0, rm)
+#define ARM_MOVS_R(rd, rm) _AL3_R(ARM_INST_MOVS, rd, 0, rm)
+#define ARM_MOV_I(rd, imm) _AL3_I(ARM_INST_MOV, rd, 0, imm)
+#define ARM_MOV_SR(rd, rm, type, rs) \
+ (_AL3_SR(ARM_MOV_R(rd, rm)) | (type) << 5 | (rs) << 8)
+#define ARM_MOV_SI(rd, rm, type, imm6) \
+ (ARM_MOV_R(rd, rm) | (type) << 5 | (imm6) << 7)
+
+#define ARM_MOVW(rd, imm) \
+ (ARM_INST_MOVW | ((imm) >> 12) << 16 | (rd) << 12 | ((imm) & 0x0fff))
+
+#define ARM_MOVT(rd, imm) \
+ (ARM_INST_MOVT | ((imm) >> 12) << 16 | (rd) << 12 | ((imm) & 0x0fff))
+
+#define ARM_MUL(rd, rm, rn) (ARM_INST_MUL | (rd) << 16 | (rm) << 8 | (rn))
+
+#define ARM_POP(regs) (ARM_INST_POP | (regs))
+#define ARM_PUSH(regs) (ARM_INST_PUSH | (regs))
+
+#define ARM_ORR_R(rd, rn, rm) _AL3_R(ARM_INST_ORR, rd, rn, rm)
+#define ARM_ORR_I(rd, rn, imm) _AL3_I(ARM_INST_ORR, rd, rn, imm)
+#define ARM_ORR_SR(rd, rn, rm, type, rs) \
+ (_AL3_SR(ARM_ORR_R(rd, rn, rm)) | (type) << 5 | (rs) << 8)
+#define ARM_ORRS_R(rd, rn, rm) _AL3_R(ARM_INST_ORRS, rd, rn, rm)
+#define ARM_ORRS_SR(rd, rn, rm, type, rs) \
+ (_AL3_SR(ARM_ORRS_R(rd, rn, rm)) | (type) << 5 | (rs) << 8)
+#define ARM_ORR_SI(rd, rn, rm, type, imm6) \
+ (ARM_ORR_R(rd, rn, rm) | (type) << 5 | (imm6) << 7)
+#define ARM_ORRS_SI(rd, rn, rm, type, imm6) \
+ (ARM_ORRS_R(rd, rn, rm) | (type) << 5 | (imm6) << 7)
+
+#define ARM_REV(rd, rm) (ARM_INST_REV | (rd) << 12 | (rm))
+#define ARM_REV16(rd, rm) (ARM_INST_REV16 | (rd) << 12 | (rm))
+
+#define ARM_RSB_I(rd, rn, imm) _AL3_I(ARM_INST_RSB, rd, rn, imm)
+#define ARM_RSBS_I(rd, rn, imm) _AL3_I(ARM_INST_RSBS, rd, rn, imm)
+#define ARM_RSC_I(rd, rn, imm) _AL3_I(ARM_INST_RSC, rd, rn, imm)
+
+#define ARM_SUB_R(rd, rn, rm) _AL3_R(ARM_INST_SUB, rd, rn, rm)
+#define ARM_SUBS_R(rd, rn, rm) _AL3_R(ARM_INST_SUBS, rd, rn, rm)
+#define ARM_RSB_R(rd, rn, rm) _AL3_R(ARM_INST_RSB, rd, rn, rm)
+#define ARM_SBC_R(rd, rn, rm) _AL3_R(ARM_INST_SBC, rd, rn, rm)
+#define ARM_SBCS_R(rd, rn, rm) _AL3_R(ARM_INST_SBCS, rd, rn, rm)
+#define ARM_SUB_I(rd, rn, imm) _AL3_I(ARM_INST_SUB, rd, rn, imm)
+#define ARM_SUBS_I(rd, rn, imm) _AL3_I(ARM_INST_SUBS, rd, rn, imm)
+#define ARM_SBC_I(rd, rn, imm) _AL3_I(ARM_INST_SBC, rd, rn, imm)
+
+#define ARM_TST_R(rn, rm) _AL3_R(ARM_INST_TST, 0, rn, rm)
+#define ARM_TST_I(rn, imm) _AL3_I(ARM_INST_TST, 0, rn, imm)
+
+#define ARM_UDIV(rd, rn, rm) (ARM_INST_UDIV | (rd) << 16 | (rn) | (rm) << 8)
+#define ARM_SDIV(rd, rn, rm) (ARM_INST_SDIV | (rd) << 16 | (rn) | (rm) << 8)
+
+#define ARM_UMULL(rd_lo, rd_hi, rn, rm) (ARM_INST_UMULL | (rd_hi) << 16 \
+ | (rd_lo) << 12 | (rm) << 8 | rn)
+
+#define ARM_MLS(rd, rn, rm, ra) (ARM_INST_MLS | (rd) << 16 | (rn) | (rm) << 8 \
+ | (ra) << 12)
+#define ARM_UXTH(rd, rm) (ARM_INST_UXTH | (rd) << 12 | (rm))
+
+#endif /* PFILTER_OPCODES_ARM_H */