net: filter: Just In Time compiler for sparc
authorDavid S. Miller <davem@davemloft.net>
Mon, 16 Apr 2012 03:06:27 +0000 (20:06 -0700)
committerDavid S. Miller <davem@davemloft.net>
Tue, 17 Apr 2012 03:15:14 +0000 (23:15 -0400)
Signed-off-by: David S. Miller <davem@davemloft.net>
arch/sparc/Kconfig
arch/sparc/Makefile
arch/sparc/net/Makefile [new file with mode: 0644]
arch/sparc/net/bpf_jit.h [new file with mode: 0644]
arch/sparc/net/bpf_jit_asm.S [new file with mode: 0644]
arch/sparc/net/bpf_jit_comp.c [new file with mode: 0644]

index 6c0683d..5f6acce 100644 (file)
@@ -30,6 +30,7 @@ config SPARC
        select USE_GENERIC_SMP_HELPERS if SMP
        select GENERIC_PCI_IOMAP
        select HAVE_NMI_WATCHDOG if SPARC64
+       select HAVE_BPF_JIT
 
 config SPARC32
        def_bool !64BIT
index eddcfb3..0e5de13 100644 (file)
@@ -66,6 +66,7 @@ head-y                 += arch/sparc/kernel/init_task.o
 
 core-y                 += arch/sparc/kernel/
 core-y                 += arch/sparc/mm/ arch/sparc/math-emu/
+core-y                 += arch/sparc/net/
 
 libs-y                 += arch/sparc/prom/
 libs-y                 += arch/sparc/lib/
diff --git a/arch/sparc/net/Makefile b/arch/sparc/net/Makefile
new file mode 100644 (file)
index 0000000..1306a58
--- /dev/null
@@ -0,0 +1,4 @@
+#
+# Arch-specific network modules
+#
+obj-$(CONFIG_BPF_JIT) += bpf_jit_asm.o bpf_jit_comp.o
diff --git a/arch/sparc/net/bpf_jit.h b/arch/sparc/net/bpf_jit.h
new file mode 100644 (file)
index 0000000..74f048b
--- /dev/null
@@ -0,0 +1,52 @@
+#ifndef _BPF_JIT_H
+#define _BPF_JIT_H
+
+/* Conventions:
+ *  %g1 : temporary
+ *  %g2 : Secondary temporary used by SKB data helper stubs.
+ *  %o0 : pointer to skb (first argument given to JIT function)
+ *  %o1 : BPF A accumulator
+ *  %o2 : BPF X accumulator
+ *  %o3 : Holds saved %o7 so we can call helper functions without needing
+ *        to allocate a register window.
+ *  %o4 : skb->data
+ *  %o5 : skb->len - skb->data_len
+ */
+
+#ifndef __ASSEMBLER__
+#define G0             0x00
+#define G1             0x01
+#define G3             0x03
+#define G6             0x06
+#define O0             0x08
+#define O1             0x09
+#define O2             0x0a
+#define O3             0x0b
+#define O4             0x0c
+#define O5             0x0d
+#define SP             0x0e
+#define O7             0x0f
+#define FP             0x1e
+
+#define r_SKB          O0
+#define r_A            O1
+#define r_X            O2
+#define r_saved_O7     O3
+#define r_HEADLEN      O4
+#define r_SKB_DATA     O5
+#define r_TMP          G1
+#define r_TMP2         G2
+#define r_OFF          G3
+#else
+#define r_SKB          %o0
+#define r_A            %o1
+#define r_X            %o2
+#define r_saved_O7     %o3
+#define r_HEADLEN      %o4
+#define r_SKB_DATA     %o5
+#define r_TMP          %g1
+#define r_TMP2         %g2
+#define r_OFF          %g3
+#endif
+
+#endif /* _BPF_JIT_H */
diff --git a/arch/sparc/net/bpf_jit_asm.S b/arch/sparc/net/bpf_jit_asm.S
new file mode 100644 (file)
index 0000000..fdc6932
--- /dev/null
@@ -0,0 +1,199 @@
+#include <asm/ptrace.h>
+
+#include "bpf_jit.h"
+
+#ifdef CONFIG_SPARC64
+#define SAVE_SZ                176
+#define SCRATCH_OFF    STACK_BIAS + 128
+#define BE_PTR(label)  be,pn %xcc, label
+#else
+#define SAVE_SZ                96
+#define SCRATCH_OFF    72
+#define BE_PTR(label)  be label
+#endif
+
+#define SKF_MAX_NEG_OFF        (-0x200000) /* SKF_LL_OFF from filter.h */
+
+       .text
+       .globl  bpf_jit_load_word
+bpf_jit_load_word:
+       cmp     r_OFF, 0
+       bl      bpf_slow_path_word_neg
+        nop
+       .globl  bpf_jit_load_word_positive_offset
+bpf_jit_load_word_positive_offset:
+       sub     r_HEADLEN, r_OFF, r_TMP
+       cmp     r_TMP, 3
+       ble     bpf_slow_path_word
+        add    r_SKB_DATA, r_OFF, r_TMP
+       andcc   r_TMP, 3, %g0
+       bne     load_word_unaligned
+        nop
+       retl
+        ld     [r_SKB_DATA + r_OFF], r_A
+load_word_unaligned:
+       ldub    [r_TMP + 0x0], r_OFF
+       ldub    [r_TMP + 0x1], r_TMP2
+       sll     r_OFF, 8, r_OFF
+       or      r_OFF, r_TMP2, r_OFF
+       ldub    [r_TMP + 0x2], r_TMP2
+       sll     r_OFF, 8, r_OFF
+       or      r_OFF, r_TMP2, r_OFF
+       ldub    [r_TMP + 0x3], r_TMP2
+       sll     r_OFF, 8, r_OFF
+       retl
+        or     r_OFF, r_TMP2, r_A
+
+       .globl  bpf_jit_load_half
+bpf_jit_load_half:
+       cmp     r_OFF, 0
+       bl      bpf_slow_path_half_neg
+        nop
+       .globl  bpf_jit_load_half_positive_offset
+bpf_jit_load_half_positive_offset:
+       sub     r_HEADLEN, r_OFF, r_TMP
+       cmp     r_TMP, 1
+       ble     bpf_slow_path_half
+        add    r_SKB_DATA, r_OFF, r_TMP
+       andcc   r_TMP, 1, %g0
+       bne     load_half_unaligned
+        nop
+       retl
+        lduh   [r_SKB_DATA + r_OFF], r_A
+load_half_unaligned:
+       ldub    [r_TMP + 0x0], r_OFF
+       ldub    [r_TMP + 0x1], r_TMP2
+       sll     r_OFF, 8, r_OFF
+       retl
+        or     r_OFF, r_TMP2, r_A
+
+       .globl  bpf_jit_load_byte
+bpf_jit_load_byte:
+       cmp     r_OFF, 0
+       bl      bpf_slow_path_byte_neg
+        nop
+       .globl  bpf_jit_load_byte_positive_offset
+bpf_jit_load_byte_positive_offset:
+       cmp     r_OFF, r_HEADLEN
+       bge     bpf_slow_path_byte
+        nop
+       retl
+        ldub   [r_SKB_DATA + r_OFF], r_A
+
+       .globl  bpf_jit_load_byte_msh
+bpf_jit_load_byte_msh:
+       cmp     r_OFF, 0
+       bl      bpf_slow_path_byte_msh_neg
+        nop
+       .globl  bpf_jit_load_byte_msh_positive_offset
+bpf_jit_load_byte_msh_positive_offset:
+       cmp     r_OFF, r_HEADLEN
+       bge     bpf_slow_path_byte_msh
+        nop
+       ldub    [r_SKB_DATA + r_OFF], r_OFF
+       and     r_OFF, 0xf, r_OFF
+       retl
+        sll    r_OFF, 2, r_X
+
+#define bpf_slow_path_common(LEN)      \
+       save    %sp, -SAVE_SZ, %sp;     \
+       mov     %i0, %o0;               \
+       mov     r_OFF, %o1;             \
+       add     %fp, SCRATCH_OFF, %o2;  \
+       call    skb_copy_bits;          \
+        mov    (LEN), %o3;             \
+       cmp     %o0, 0;                 \
+       restore;
+
+bpf_slow_path_word:
+       bpf_slow_path_common(4)
+       bl      bpf_error
+        ld     [%sp + SCRATCH_OFF], r_A
+       retl
+        nop
+bpf_slow_path_half:
+       bpf_slow_path_common(2)
+       bl      bpf_error
+        lduh   [%sp + SCRATCH_OFF], r_A
+       retl
+        nop
+bpf_slow_path_byte:
+       bpf_slow_path_common(1)
+       bl      bpf_error
+        ldub   [%sp + SCRATCH_OFF], r_A
+       retl
+        nop
+bpf_slow_path_byte_msh:
+       bpf_slow_path_common(1)
+       bl      bpf_error
+        ldub   [%sp + SCRATCH_OFF], r_A
+       and     r_OFF, 0xf, r_OFF
+       retl
+        sll    r_OFF, 2, r_X
+
+#define bpf_negative_common(LEN)                       \
+       save    %sp, -SAVE_SZ, %sp;                     \
+       mov     %i0, %o0;                               \
+       mov     r_OFF, %o1;                             \
+       call    bpf_internal_load_pointer_neg_helper;   \
+        mov    (LEN), %o2;                             \
+       mov     %o0, r_TMP;                             \
+       cmp     %o0, 0;                                 \
+       BE_PTR(bpf_error);                              \
+        restore;
+
+bpf_slow_path_word_neg:
+       sethi   %hi(SKF_MAX_NEG_OFF), r_TMP
+       cmp     r_OFF, r_TMP
+       bl      bpf_error
+        nop
+       .globl  bpf_jit_load_word_negative_offset
+bpf_jit_load_word_negative_offset:
+       bpf_negative_common(4)
+       andcc   r_TMP, 3, %g0
+       bne     load_word_unaligned
+        nop
+       retl
+        ld     [r_TMP], r_A
+
+bpf_slow_path_half_neg:
+       sethi   %hi(SKF_MAX_NEG_OFF), r_TMP
+       cmp     r_OFF, r_TMP
+       bl      bpf_error
+        nop
+       .globl  bpf_jit_load_half_negative_offset
+bpf_jit_load_half_negative_offset:
+       bpf_negative_common(2)
+       andcc   r_TMP, 1, %g0
+       bne     load_half_unaligned
+        nop
+       retl
+        lduh   [r_TMP], r_A
+
+bpf_slow_path_byte_neg:
+       sethi   %hi(SKF_MAX_NEG_OFF), r_TMP
+       cmp     r_OFF, r_TMP
+       bl      bpf_error
+        nop
+       .globl  bpf_jit_load_byte_negative_offset
+bpf_jit_load_byte_negative_offset:
+       bpf_negative_common(1)
+       retl
+        ldub   [r_TMP], r_A
+
+bpf_slow_path_byte_msh_neg:
+       sethi   %hi(SKF_MAX_NEG_OFF), r_TMP
+       cmp     r_OFF, r_TMP
+       bl      bpf_error
+        nop
+       .globl  bpf_jit_load_byte_msh_negative_offset
+bpf_jit_load_byte_msh_negative_offset:
+       bpf_negative_common(1)
+       ldub    [r_TMP], r_OFF
+       and     r_OFF, 0xf, r_OFF
+       retl
+        sll    r_OFF, 2, r_X
+
+bpf_error:
+       jmpl    r_saved_O7 + 8, %g0
+        clr    %o0
diff --git a/arch/sparc/net/bpf_jit_comp.c b/arch/sparc/net/bpf_jit_comp.c
new file mode 100644 (file)
index 0000000..86349ca
--- /dev/null
@@ -0,0 +1,785 @@
+#include <linux/moduleloader.h>
+#include <linux/workqueue.h>
+#include <linux/netdevice.h>
+#include <linux/filter.h>
+#include <linux/cache.h>
+
+#include <asm/cacheflush.h>
+#include <asm/ptrace.h>
+
+#include "bpf_jit.h"
+
+int bpf_jit_enable __read_mostly;
+
+/* assembly code in arch/sparc/net/bpf_jit_asm.S */
+extern u32 bpf_jit_load_word[];
+extern u32 bpf_jit_load_half[];
+extern u32 bpf_jit_load_byte[];
+extern u32 bpf_jit_load_byte_msh[];
+extern u32 bpf_jit_load_word_positive_offset[];
+extern u32 bpf_jit_load_half_positive_offset[];
+extern u32 bpf_jit_load_byte_positive_offset[];
+extern u32 bpf_jit_load_byte_msh_positive_offset[];
+extern u32 bpf_jit_load_word_negative_offset[];
+extern u32 bpf_jit_load_half_negative_offset[];
+extern u32 bpf_jit_load_byte_negative_offset[];
+extern u32 bpf_jit_load_byte_msh_negative_offset[];
+
+static inline bool is_simm13(unsigned int value)
+{
+       return value + 0x1000 < 0x2000;
+}
+
+static void bpf_flush_icache(void *start_, void *end_)
+{
+#ifdef CONFIG_SPARC64
+       /* Cheetah's I-cache is fully coherent.  */
+       if (tlb_type == spitfire) {
+               unsigned long start = (unsigned long) start_;
+               unsigned long end = (unsigned long) end_;
+
+               start &= ~7UL;
+               end = (end + 7UL) & ~7UL;
+               while (start < end) {
+                       flushi(start);
+                       start += 32;
+               }
+       }
+#endif
+}
+
+#define SEEN_DATAREF 1 /* might call external helpers */
+#define SEEN_XREG    2 /* ebx is used */
+#define SEEN_MEM     4 /* use mem[] for temporary storage */
+
+#define S13(X)         ((X) & 0x1fff)
+#define IMMED          0x00002000
+#define RD(X)          ((X) << 25)
+#define RS1(X)         ((X) << 14)
+#define RS2(X)         ((X))
+#define OP(X)          ((X) << 30)
+#define OP2(X)         ((X) << 22)
+#define OP3(X)         ((X) << 19)
+#define COND(X)                ((X) << 25)
+#define F1(X)          OP(X)
+#define F2(X, Y)       (OP(X) | OP2(Y))
+#define F3(X, Y)       (OP(X) | OP3(Y))
+
+#define CONDN          COND (0x0)
+#define CONDE          COND (0x1)
+#define CONDLE         COND (0x2)
+#define CONDL          COND (0x3)
+#define CONDLEU                COND (0x4)
+#define CONDCS         COND (0x5)
+#define CONDNEG                COND (0x6)
+#define CONDVC         COND (0x7)
+#define CONDA          COND (0x8)
+#define CONDNE         COND (0x9)
+#define CONDG          COND (0xa)
+#define CONDGE         COND (0xb)
+#define CONDGU         COND (0xc)
+#define CONDCC         COND (0xd)
+#define CONDPOS                COND (0xe)
+#define CONDVS         COND (0xf)
+
+#define CONDGEU                CONDCC
+#define CONDLU         CONDCS
+
+#define WDISP22(X)     (((X) >> 2) & 0x3fffff)
+
+#define BA             (F2(0, 2) | CONDA)
+#define BGU            (F2(0, 2) | CONDGU)
+#define BLEU           (F2(0, 2) | CONDLEU)
+#define BGEU           (F2(0, 2) | CONDGEU)
+#define BLU            (F2(0, 2) | CONDLU)
+#define BE             (F2(0, 2) | CONDE)
+#define BNE            (F2(0, 2) | CONDNE)
+
+#ifdef CONFIG_SPARC64
+#define BNE_PTR                (F2(0, 1) | CONDNE | (2 << 20))
+#else
+#define BNE_PTR                BNE
+#endif
+
+#define SETHI(K, REG)  \
+       (F2(0, 0x4) | RD(REG) | (((K) >> 10) & 0x3fffff))
+#define OR_LO(K, REG)  \
+       (F3(2, 0x02) | IMMED | RS1(REG) | ((K) & 0x3ff) | RD(REG))
+
+#define ADD            F3(2, 0x00)
+#define AND            F3(2, 0x01)
+#define ANDCC          F3(2, 0x11)
+#define OR             F3(2, 0x02)
+#define SUB            F3(2, 0x04)
+#define SUBCC          F3(2, 0x14)
+#define MUL            F3(2, 0x0a)     /* umul */
+#define DIV            F3(2, 0x0e)     /* udiv */
+#define SLL            F3(2, 0x25)
+#define SRL            F3(2, 0x26)
+#define JMPL           F3(2, 0x38)
+#define CALL           F1(1)
+#define BR             F2(0, 0x01)
+#define RD_Y           F3(2, 0x28)
+#define WR_Y           F3(2, 0x30)
+
+#define LD32           F3(3, 0x00)
+#define LD8            F3(3, 0x01)
+#define LD16           F3(3, 0x02)
+#define LD64           F3(3, 0x0b)
+#define ST32           F3(3, 0x04)
+
+#ifdef CONFIG_SPARC64
+#define LDPTR          LD64
+#define BASE_STACKFRAME        176
+#else
+#define LDPTR          LD32
+#define BASE_STACKFRAME        96
+#endif
+
+#define LD32I          (LD32 | IMMED)
+#define LD8I           (LD8 | IMMED)
+#define LD16I          (LD16 | IMMED)
+#define LD64I          (LD64 | IMMED)
+#define LDPTRI         (LDPTR | IMMED)
+#define ST32I          (ST32 | IMMED)
+
+#define emit_nop()             \
+do {                           \
+       *prog++ = SETHI(0, G0); \
+} while (0)
+
+#define emit_neg()                                     \
+do {   /* sub %g0, r_A, r_A */                         \
+       *prog++ = SUB | RS1(G0) | RS2(r_A) | RD(r_A);   \
+} while (0)
+
+#define emit_reg_move(FROM, TO)                                \
+do {   /* or %g0, FROM, TO */                          \
+       *prog++ = OR | RS1(G0) | RS2(FROM) | RD(TO);    \
+} while (0)
+
+#define emit_clear(REG)                                        \
+do {   /* or %g0, %g0, REG */                          \
+       *prog++ = OR | RS1(G0) | RS2(G0) | RD(REG);     \
+} while (0)
+
+#define emit_set_const(K, REG)                                 \
+do {   /* sethi %hi(K), REG */                                 \
+       *prog++ = SETHI(K, REG);                                \
+       /* or REG, %lo(K), REG */                               \
+       *prog++ = OR_LO(K, REG);                                \
+} while (0)
+
+       /* Emit
+        *
+        *      OP      r_A, r_X, r_A
+        */
+#define emit_alu_X(OPCODE)                                     \
+do {                                                           \
+       seen |= SEEN_XREG;                                      \
+       *prog++ = OPCODE | RS1(r_A) | RS2(r_X) | RD(r_A);       \
+} while (0)
+
+       /* Emit either:
+        *
+        *      OP      r_A, K, r_A
+        *
+        * or
+        *
+        *      sethi   %hi(K), r_TMP
+        *      or      r_TMP, %lo(K), r_TMP
+        *      OP      r_A, r_TMP, r_A
+        *
+        * depending upon whether K fits in a signed 13-bit
+        * immediate instruction field.  Emit nothing if K
+        * is zero.
+        */
+#define emit_alu_K(OPCODE, K)                                  \
+do {                                                           \
+       if (K) {                                                \
+               unsigned int _insn = OPCODE;                    \
+               _insn |= RS1(r_A) | RD(r_A);                    \
+               if (is_simm13(K)) {                             \
+                       *prog++ = _insn | IMMED | S13(K);       \
+               } else {                                        \
+                       emit_set_const(K, r_TMP);               \
+                       *prog++ = _insn | RS2(r_TMP);           \
+               }                                               \
+       }                                                       \
+} while (0)
+
+#define emit_loadimm(K, DEST)                                          \
+do {                                                                   \
+       if (is_simm13(K)) {                                             \
+               /* or %g0, K, DEST */                                   \
+               *prog++ = OR | IMMED | RS1(G0) | S13(K) | RD(DEST);     \
+       } else {                                                        \
+               emit_set_const(K, DEST);                                \
+       }                                                               \
+} while (0)
+
+#define emit_loadptr(BASE, STRUCT, FIELD, DEST)                                \
+do {   unsigned int _off = offsetof(STRUCT, FIELD);                    \
+       BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(void *));    \
+       *prog++ = LDPTRI | RS1(BASE) | S13(_off) | RD(DEST);            \
+} while(0)
+
+#define emit_load32(BASE, STRUCT, FIELD, DEST)                         \
+do {   unsigned int _off = offsetof(STRUCT, FIELD);                    \
+       BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(u32));       \
+       *prog++ = LD32I | RS1(BASE) | S13(_off) | RD(DEST);             \
+} while(0)
+
+#define emit_load16(BASE, STRUCT, FIELD, DEST)                         \
+do {   unsigned int _off = offsetof(STRUCT, FIELD);                    \
+       BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(u16));       \
+       *prog++ = LD16I | RS1(BASE) | S13(_off) | RD(DEST);             \
+} while(0)
+
+#define __emit_load8(BASE, STRUCT, FIELD, DEST)                                \
+do {   unsigned int _off = offsetof(STRUCT, FIELD);                    \
+       *prog++ = LD8I | RS1(BASE) | S13(_off) | RD(DEST);              \
+} while(0)
+
+#define emit_load8(BASE, STRUCT, FIELD, DEST)                          \
+do {   BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(u8));        \
+       __emit_load8(BASE, STRUCT, FIELD, DEST);                        \
+} while(0)
+
+#define emit_ldmem(OFF, DEST)                                  \
+do {   *prog++ = LD32I | RS1(FP) | S13(-(OFF)) | RD(DEST);     \
+} while(0)
+
+#define emit_stmem(OFF, SRC)                                   \
+do {   *prog++ = LD32I | RS1(FP) | S13(-(OFF)) | RD(SRC);      \
+} while(0)
+
+#define cpu_off                offsetof(struct thread_info, cpu)
+
+#ifdef CONFIG_SMP
+#ifdef CONFIG_SPARC64
+#define emit_load_cpu(REG)                                             \
+       emit_load16(G6, struct thread_info, cpu, REG)
+#else
+#define emit_load_cpu(REG)                                             \
+       emit_load32(G6, struct thread_info, cpu, REG)
+#endif
+#else
+#define emit_load_cpu(REG)     emit_clear(REG)
+#endif
+
+#define emit_skb_loadptr(FIELD, DEST) \
+       emit_loadptr(r_SKB, struct sk_buff, FIELD, DEST)
+#define emit_skb_load32(FIELD, DEST) \
+       emit_load32(r_SKB, struct sk_buff, FIELD, DEST)
+#define emit_skb_load16(FIELD, DEST) \
+       emit_load16(r_SKB, struct sk_buff, FIELD, DEST)
+#define __emit_skb_load8(FIELD, DEST) \
+       __emit_load8(r_SKB, struct sk_buff, FIELD, DEST)
+#define emit_skb_load8(FIELD, DEST) \
+       emit_load8(r_SKB, struct sk_buff, FIELD, DEST)
+
+#define emit_jmpl(BASE, IMM_OFF, LREG) \
+       *prog++ = (JMPL | IMMED | RS1(BASE) | S13(IMM_OFF) | RD(LREG))
+
+#define emit_call(FUNC)                                        \
+do {   void *_here = image + addrs[i] - 8;             \
+       unsigned int _off = (void *)(FUNC) - _here;     \
+       *prog++ = CALL | (((_off) >> 2) & 0x3fffffff);  \
+       emit_nop();                                     \
+} while (0)
+
+#define emit_branch(BR_OPC, DEST)                      \
+do {   unsigned int _here = addrs[i] - 8;              \
+       *prog++ = BR_OPC | WDISP22((DEST) - _here);     \
+} while(0)
+
+#define emit_branch_off(BR_OPC, OFF)                   \
+do {   *prog++ = BR_OPC | WDISP22(OFF);                \
+} while(0)
+
+#define emit_jump(DEST)                emit_branch(BA, DEST)
+
+#define emit_read_y(REG)       *prog++ = RD_Y | RD(REG);
+#define emit_write_y(REG)      *prog++ = WR_Y | IMMED | RS1(REG) | S13(0);
+
+#define emit_cmp(R1, R2) \
+       *prog++ = (SUBCC | RS1(R1) | RS2(R2) | RD(G0))
+
+#define emit_cmpi(R1, IMM) \
+       *prog++ = (SUBCC | IMMED | RS1(R1) | S13(IMM) | RD(G0));
+
+#define emit_btst(R1, R2) \
+       *prog++ = (ANDCC | RS1(R1) | RS2(R2) | RD(G0))
+
+#define emit_btsti(R1, IMM) \
+       *prog++ = (ANDCC | IMMED | RS1(R1) | S13(IMM) | RD(G0));
+
+#define emit_sub(R1, R2, R3) \
+       *prog++ = (SUB | RS1(R1) | RS2(R2) | RD(R3))
+
+#define emit_subi(R1, IMM, R3) \
+       *prog++ = (SUB | IMMED | RS1(R1) | S13(IMM) | RD(R3))
+
+#define emit_add(R1, R2, R3) \
+       *prog++ = (ADD | RS1(R1) | RS2(R2) | RD(R3))
+
+#define emit_addi(R1, IMM, R3) \
+       *prog++ = (ADD | IMMED | RS1(R1) | S13(IMM) | RD(R3))
+
+#define emit_alloc_stack(SZ) \
+       *prog++ = (SUB | IMMED | RS1(SP) | S13(SZ) | RD(SP))
+
+#define emit_release_stack(SZ) \
+       *prog++ = (ADD | IMMED | RS1(SP) | S13(SZ) | RD(SP))
+
+void bpf_jit_compile(struct sk_filter *fp)
+{
+       unsigned int cleanup_addr, proglen, oldproglen = 0;
+       u32 temp[8], *prog, *func, seen = 0, pass;
+       const struct sock_filter *filter = fp->insns;
+       int i, flen = fp->len, pc_ret0 = -1;
+       unsigned int *addrs;
+       void *image;
+
+       if (!bpf_jit_enable)
+               return;
+
+       addrs = kmalloc(flen * sizeof(*addrs), GFP_KERNEL);
+       if (addrs == NULL)
+               return;
+
+       /* Before first pass, make a rough estimation of addrs[]
+        * each bpf instruction is translated to less than 64 bytes
+        */
+       for (proglen = 0, i = 0; i < flen; i++) {
+               proglen += 64;
+               addrs[i] = proglen;
+       }
+       cleanup_addr = proglen; /* epilogue address */
+       image = NULL;
+       for (pass = 0; pass < 10; pass++) {
+               u8 seen_or_pass0 = (pass == 0) ? (SEEN_XREG | SEEN_DATAREF | SEEN_MEM) : seen;
+
+               /* no prologue/epilogue for trivial filters (RET something) */
+               proglen = 0;
+               prog = temp;
+
+               /* Prologue */
+               if (seen_or_pass0) {
+                       if (seen_or_pass0 & SEEN_MEM) {
+                               unsigned int sz = BASE_STACKFRAME;
+                               sz += BPF_MEMWORDS * sizeof(u32);
+                               emit_alloc_stack(sz);
+                       }
+
+                       /* Make sure we dont leek kernel memory. */
+                       if (seen_or_pass0 & SEEN_XREG)
+                               emit_clear(r_X);
+
+                       /* If this filter needs to access skb data,
+                        * load %o4 and %o4 with:
+                        *  %o4 = skb->len - skb->data_len
+                        *  %o5 = skb->data
+                        * And also back up %o7 into r_saved_O7 so we can
+                        * invoke the stubs using 'call'.
+                        */
+                       if (seen_or_pass0 & SEEN_DATAREF) {
+                               emit_load32(r_SKB, struct sk_buff, len, r_HEADLEN);
+                               emit_load32(r_SKB, struct sk_buff, data_len, r_TMP);
+                               emit_sub(r_HEADLEN, r_TMP, r_HEADLEN);
+                               emit_loadptr(r_SKB, struct sk_buff, data, r_SKB_DATA);
+                       }
+               }
+               emit_reg_move(O7, r_saved_O7);
+
+               switch (filter[0].code) {
+               case BPF_S_RET_K:
+               case BPF_S_LD_W_LEN:
+               case BPF_S_ANC_PROTOCOL:
+               case BPF_S_ANC_PKTTYPE:
+               case BPF_S_ANC_IFINDEX:
+               case BPF_S_ANC_MARK:
+               case BPF_S_ANC_RXHASH:
+               case BPF_S_ANC_CPU:
+               case BPF_S_ANC_QUEUE:
+               case BPF_S_LD_W_ABS:
+               case BPF_S_LD_H_ABS:
+               case BPF_S_LD_B_ABS:
+                       /* The first instruction sets the A register (or is
+                        * a "RET 'constant'")
+                        */
+                       break;
+               default:
+                       /* Make sure we dont leak kernel information to the
+                        * user.
+                        */
+                       emit_clear(r_A); /* A = 0 */
+               }
+
+               for (i = 0; i < flen; i++) {
+                       unsigned int K = filter[i].k;
+                       unsigned int t_offset;
+                       unsigned int f_offset;
+                       u32 t_op, f_op;
+                       int ilen;
+
+                       switch (filter[i].code) {
+                       case BPF_S_ALU_ADD_X:   /* A += X; */
+                               emit_alu_X(ADD);
+                               break;
+                       case BPF_S_ALU_ADD_K:   /* A += K; */
+                               emit_alu_K(ADD, K);
+                               break;
+                       case BPF_S_ALU_SUB_X:   /* A -= X; */
+                               emit_alu_X(SUB);
+                               break;
+                       case BPF_S_ALU_SUB_K:   /* A -= K */
+                               emit_alu_K(SUB, K);
+                               break;
+                       case BPF_S_ALU_AND_X:   /* A &= X */
+                               emit_alu_X(AND);
+                               break;
+                       case BPF_S_ALU_AND_K:   /* A &= K */
+                               emit_alu_K(AND, K);
+                               break;
+                       case BPF_S_ALU_OR_X:    /* A |= X */
+                               emit_alu_X(OR);
+                               break;
+                       case BPF_S_ALU_OR_K:    /* A |= K */
+                               emit_alu_K(OR, K);
+                               break;
+                       case BPF_S_ALU_LSH_X:   /* A <<= X */
+                               emit_alu_X(SLL);
+                               break;
+                       case BPF_S_ALU_LSH_K:   /* A <<= K */
+                               emit_alu_K(SLL, K);
+                               break;
+                       case BPF_S_ALU_RSH_X:   /* A >>= X */
+                               emit_alu_X(SRL);
+                               break;
+                       case BPF_S_ALU_RSH_K:   /* A >>= K */
+                               emit_alu_K(SRL, K);
+                               break;
+                       case BPF_S_ALU_MUL_X:   /* A *= X; */
+                               emit_alu_X(MUL);
+                               break;
+                       case BPF_S_ALU_MUL_K:   /* A *= K */
+                               emit_alu_K(MUL, K);
+                               break;
+                       case BPF_S_ALU_DIV_K:   /* A /= K */
+                               emit_alu_K(MUL, K);
+                               emit_read_y(r_A);
+                               break;
+                       case BPF_S_ALU_DIV_X:   /* A /= X; */
+                               emit_cmpi(r_X, 0);
+                               if (pc_ret0 > 0) {
+                                       t_offset = addrs[pc_ret0 - 1];
+#ifdef CONFIG_SPARC32
+                                       emit_branch(BE, t_offset + 20);
+#else
+                                       emit_branch(BE, t_offset + 8);
+#endif
+                                       emit_nop(); /* delay slot */
+                               } else {
+                                       emit_branch_off(BNE, 16);
+                                       emit_nop();
+#ifdef CONFIG_SPARC32
+                                       emit_jump(cleanup_addr + 20);
+#else
+                                       emit_jump(cleanup_addr + 8);
+#endif
+                                       emit_clear(r_A);
+                               }
+                               emit_write_y(G0);
+#ifdef CONFIG_SPARC32
+                               emit_nop();
+                               emit_nop();
+                               emit_nop();
+#endif
+                               emit_alu_X(DIV);
+                               break;
+                       case BPF_S_ALU_NEG:
+                               emit_neg();
+                               break;
+                       case BPF_S_RET_K:
+                               if (!K) {
+                                       if (pc_ret0 == -1)
+                                               pc_ret0 = i;
+                                       emit_clear(r_A);
+                               } else {
+                                       emit_loadimm(K, r_A);
+                               }
+                               /* Fallthrough */
+                       case BPF_S_RET_A:
+                               if (seen_or_pass0) {
+                                       if (i != flen - 1) {
+                                               emit_jump(cleanup_addr);
+                                               emit_nop();
+                                               break;
+                                       }
+                                       if (seen_or_pass0 & SEEN_MEM) {
+                                               unsigned int sz = BASE_STACKFRAME;
+                                               sz += BPF_MEMWORDS * sizeof(u32);
+                                               emit_release_stack(sz);
+                                       }
+                               }
+                               /* jmpl %r_saved_O7 + 8, %g0 */
+                               emit_jmpl(r_saved_O7, 8, G0);
+                               emit_reg_move(r_A, O0); /* delay slot */
+                               break;
+                       case BPF_S_MISC_TAX:
+                               seen |= SEEN_XREG;
+                               emit_reg_move(r_A, r_X);
+                               break;
+                       case BPF_S_MISC_TXA:
+                               seen |= SEEN_XREG;
+                               emit_reg_move(r_X, r_A);
+                               break;
+                       case BPF_S_ANC_CPU:
+                               emit_load_cpu(r_A);
+                               break;
+                       case BPF_S_ANC_PROTOCOL:
+                               emit_skb_load16(protocol, r_A);
+                               break;
+#if 0
+                               /* GCC won't let us take the address of
+                                * a bit field even though we very much
+                                * know what we are doing here.
+                                */
+                       case BPF_S_ANC_PKTTYPE:
+                               __emit_skb_load8(pkt_type, r_A);
+                               emit_alu_K(SRL, 5);
+                               break;
+#endif
+                       case BPF_S_ANC_IFINDEX:
+                               emit_skb_loadptr(dev, r_A);
+                               emit_cmpi(r_A, 0);
+                               emit_branch(BNE_PTR, cleanup_addr + 4);
+                               emit_nop();
+                               emit_load32(r_A, struct net_device, ifindex, r_A);
+                               break;
+                       case BPF_S_ANC_MARK:
+                               emit_skb_load32(mark, r_A);
+                               break;
+                       case BPF_S_ANC_QUEUE:
+                               emit_skb_load16(queue_mapping, r_A);
+                               break;
+                       case BPF_S_ANC_HATYPE:
+                               emit_skb_loadptr(dev, r_A);
+                               emit_cmpi(r_A, 0);
+                               emit_branch(BNE_PTR, cleanup_addr + 4);
+                               emit_nop();
+                               emit_load16(r_A, struct net_device, type, r_A);
+                               break;
+                       case BPF_S_ANC_RXHASH:
+                               emit_skb_load32(rxhash, r_A);
+                               break;
+
+                       case BPF_S_LD_IMM:
+                               emit_loadimm(K, r_A);
+                               break;
+                       case BPF_S_LDX_IMM:
+                               emit_loadimm(K, r_X);
+                               break;
+                       case BPF_S_LD_MEM:
+                               emit_ldmem(K * 4, r_A);
+                               break;
+                       case BPF_S_LDX_MEM:
+                               emit_ldmem(K * 4, r_X);
+                               break;
+                       case BPF_S_ST:
+                               emit_stmem(K * 4, r_A);
+                               break;
+                       case BPF_S_STX:
+                               emit_stmem(K * 4, r_X);
+                               break;
+
+#define CHOOSE_LOAD_FUNC(K, func) \
+       ((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset)
+
+                       case BPF_S_LD_W_ABS:
+                               func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_word);
+common_load:                   seen |= SEEN_DATAREF;
+                               emit_loadimm(K, r_OFF);
+                               emit_call(func);
+                               break;
+                       case BPF_S_LD_H_ABS:
+                               func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_half);
+                               goto common_load;
+                       case BPF_S_LD_B_ABS:
+                               func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_byte);
+                               goto common_load;
+                       case BPF_S_LDX_B_MSH:
+                               func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_byte_msh);
+                               goto common_load;
+                       case BPF_S_LD_W_IND:
+                               func = bpf_jit_load_word;
+common_load_ind:               seen |= SEEN_DATAREF | SEEN_XREG;
+                               if (K) {
+                                       if (is_simm13(K)) {
+                                               emit_addi(r_X, K, r_OFF);
+                                       } else {
+                                               emit_loadimm(K, r_TMP);
+                                               emit_add(r_X, r_TMP, r_OFF);
+                                       }
+                               } else {
+                                       emit_reg_move(r_X, r_OFF);
+                               }
+                               emit_call(func);
+                               break;
+                       case BPF_S_LD_H_IND:
+                               func = bpf_jit_load_half;
+                               goto common_load_ind;
+                       case BPF_S_LD_B_IND:
+                               func = bpf_jit_load_byte;
+                               goto common_load_ind;
+                       case BPF_S_JMP_JA:
+                               emit_jump(addrs[i + K]);
+                               emit_nop();
+                               break;
+
+#define COND_SEL(CODE, TOP, FOP)       \
+       case CODE:                      \
+               t_op = TOP;             \
+               f_op = FOP;             \
+               goto cond_branch
+
+                       COND_SEL(BPF_S_JMP_JGT_K, BGU, BLEU);
+                       COND_SEL(BPF_S_JMP_JGE_K, BGEU, BLU);
+                       COND_SEL(BPF_S_JMP_JEQ_K, BE, BNE);
+                       COND_SEL(BPF_S_JMP_JSET_K, BNE, BE);
+                       COND_SEL(BPF_S_JMP_JGT_X, BGU, BLEU);
+                       COND_SEL(BPF_S_JMP_JGE_X, BGEU, BLU);
+                       COND_SEL(BPF_S_JMP_JEQ_X, BE, BNE);
+                       COND_SEL(BPF_S_JMP_JSET_X, BNE, BE);
+
+cond_branch:                   f_offset = addrs[i + filter[i].jf];
+                               t_offset = addrs[i + filter[i].jt];
+
+                               /* same targets, can avoid doing the test :) */
+                               if (filter[i].jt == filter[i].jf) {
+                                       emit_jump(t_offset);
+                                       emit_nop();
+                                       break;
+                               }
+
+                               switch (filter[i].code) {
+                               case BPF_S_JMP_JGT_X:
+                               case BPF_S_JMP_JGE_X:
+                               case BPF_S_JMP_JEQ_X:
+                                       seen |= SEEN_XREG;
+                                       emit_cmp(r_A, r_X);
+                                       break;
+                               case BPF_S_JMP_JSET_X:
+                                       seen |= SEEN_XREG;
+                                       emit_btst(r_A, r_X);
+                                       break;
+                               case BPF_S_JMP_JEQ_K:
+                               case BPF_S_JMP_JGT_K:
+                               case BPF_S_JMP_JGE_K:
+                                       if (is_simm13(K)) {
+                                               emit_cmpi(r_A, K);
+                                       } else {
+                                               emit_loadimm(K, r_TMP);
+                                               emit_cmp(r_A, r_TMP);
+                                       }
+                                       break;
+                               case BPF_S_JMP_JSET_K:
+                                       if (is_simm13(K)) {
+                                               emit_btsti(r_A, K);
+                                       } else {
+                                               emit_loadimm(K, r_TMP);
+                                               emit_btst(r_A, r_TMP);
+                                       }
+                                       break;
+                               }
+                               if (filter[i].jt != 0) {
+                                       if (filter[i].jf)
+                                               t_offset += 8;
+                                       emit_branch(t_op, t_offset);
+                                       emit_nop(); /* delay slot */
+                                       if (filter[i].jf) {
+                                               emit_jump(f_offset);
+                                               emit_nop();
+                                       }
+                                       break;
+                               }
+                               emit_branch(f_op, f_offset);
+                               emit_nop(); /* delay slot */
+                               break;
+
+                       default:
+                               /* hmm, too complex filter, give up with jit compiler */
+                               goto out;
+                       }
+                       ilen = (void *) prog - (void *) temp;
+                       if (image) {
+                               if (unlikely(proglen + ilen > oldproglen)) {
+                                       pr_err("bpb_jit_compile fatal error\n");
+                                       kfree(addrs);
+                                       module_free(NULL, image);
+                                       return;
+                               }
+                               memcpy(image + proglen, temp, ilen);
+                       }
+                       proglen += ilen;
+                       addrs[i] = proglen;
+                       prog = temp;
+               }
+               /* last bpf instruction is always a RET :
+                * use it to give the cleanup instruction(s) addr
+                */
+               cleanup_addr = proglen - 8; /* jmpl; mov r_A,%o0; */
+               if (seen_or_pass0 & SEEN_MEM)
+                       cleanup_addr -= 4; /* add %sp, X, %sp; */
+
+               if (image) {
+                       if (proglen != oldproglen)
+                               pr_err("bpb_jit_compile proglen=%u != oldproglen=%u\n",
+                                      proglen, oldproglen);
+                       break;
+               }
+               if (proglen == oldproglen) {
+                       image = module_alloc(max_t(unsigned int,
+                                                  proglen,
+                                                  sizeof(struct work_struct)));
+                       if (!image)
+                               goto out;
+               }
+               oldproglen = proglen;
+       }
+
+       if (bpf_jit_enable > 1)
+               pr_err("flen=%d proglen=%u pass=%d image=%p\n",
+                      flen, proglen, pass, image);
+
+       if (image) {
+               if (bpf_jit_enable > 1)
+                       print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_ADDRESS,
+                                      16, 1, image, proglen, false);
+               bpf_flush_icache(image, image + proglen);
+               fp->bpf_func = (void *)image;
+       }
+out:
+       kfree(addrs);
+       return;
+}
+
+static void jit_free_defer(struct work_struct *arg)
+{
+       module_free(NULL, arg);
+}
+
+/* run from softirq, we must use a work_struct to call
+ * module_free() from process context
+ */
+void bpf_jit_free(struct sk_filter *fp)
+{
+       if (fp->bpf_func != sk_run_filter) {
+               struct work_struct *work = (struct work_struct *)fp->bpf_func;
+
+               INIT_WORK(work, jit_free_defer);
+               schedule_work(work);
+       }
+}