s390/bpf: Add s390x eBPF JIT compiler backend
Replace 32 bit BPF JIT backend with new 64 bit eBPF backend.
Signed-off-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/net/bpf_jit.S b/arch/s390/net/bpf_jit.S
index ba44c9f..a1c917d 100644
--- a/arch/s390/net/bpf_jit.S
+++ b/arch/s390/net/bpf_jit.S
@@ -1,134 +1,115 @@
/*
* BPF Jit compiler for s390, help functions.
*
- * Copyright IBM Corp. 2012
+ * Copyright IBM Corp. 2012,2015
*
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ * Michael Holzheu <holzheu@linux.vnet.ibm.com>
*/
+
#include <linux/linkage.h>
+#include "bpf_jit.h"
/*
* Calling convention:
- * registers %r2, %r6-%r8, %r10-%r11, %r13, %r15 are call saved
- * %r2: skb pointer
- * %r3: offset parameter
- * %r5: BPF A accumulator
- * %r8: return address
- * %r9: save register for skb pointer
- * %r10: skb->data
- * %r11: skb->len - skb->data_len (headlen)
- * %r12: BPF X accumulator
+ * registers %r7-%r10, %r11,%r13, and %r15 are call saved
+ *
+ * Input (64 bit):
+ * %r3 (%b2) = offset into skb data
+ * %r6 (%b5) = return address
+ * %r7 (%b6) = skb pointer
+ * %r12 = skb data pointer
+ *
+ * Output:
+ * %r14= %b0 = return value (read skb value)
+ *
+ * Work registers: %r2,%r4,%r5,%r14
*
* skb_copy_bits takes 4 parameters:
* %r2 = skb pointer
* %r3 = offset into skb data
* %r4 = pointer to temp buffer
* %r5 = length to copy
+ * Return value in %r2: 0 = ok
+ *
+ * bpf_internal_load_pointer_neg_helper takes 3 parameters:
+ * %r2 = skb pointer
+ * %r3 = offset into data
+ * %r4 = length to copy
+ * Return value in %r2: Pointer to data
*/
-#define SKBDATA %r8
- /* A = *(u32 *) (skb->data+K+X) */
-ENTRY(sk_load_word_ind)
- ar %r3,%r12 # offset += X
- bmr %r8 # < 0 -> return with cc
+#define SKF_MAX_NEG_OFF -0x200000 /* SKF_LL_OFF from filter.h */
- /* A = *(u32 *) (skb->data+K) */
-ENTRY(sk_load_word)
- llgfr %r1,%r3 # extend offset
- ahi %r3,4 # offset + 4
- clr %r11,%r3 # hlen <= offset + 4 ?
- jl sk_load_word_slow
- l %r5,0(%r1,%r10) # get word from skb
- xr %r1,%r1 # set cc to zero
- br %r8
+/*
+ * Load SIZE bytes from SKB
+ */
+#define sk_load_common(NAME, SIZE, LOAD) \
+ENTRY(sk_load_##NAME); \
+ ltgr %r3,%r3; /* Is offset negative? */ \
+ jl sk_load_##NAME##_slow_neg; \
+ENTRY(sk_load_##NAME##_pos); \
+ aghi %r3,SIZE; /* Offset + SIZE */ \
+ clg %r3,STK_OFF_HLEN(%r15); /* Offset + SIZE > hlen? */ \
+ jh sk_load_##NAME##_slow; \
+ LOAD %r14,-SIZE(%r3,%r12); /* Get data from skb */ \
+ b OFF_OK(%r6); /* Return */ \
+ \
+sk_load_##NAME##_slow:; \
+ lgr %r2,%r7; /* Arg1 = skb pointer */ \
+ aghi %r3,-SIZE; /* Arg2 = offset */ \
+ la %r4,STK_OFF_TMP(%r15); /* Arg3 = temp bufffer */ \
+ lghi %r5,SIZE; /* Arg4 = size */ \
+ brasl %r14,skb_copy_bits; /* Get data from skb */ \
+ LOAD %r14,STK_OFF_TMP(%r15); /* Load from temp bufffer */ \
+ ltgr %r2,%r2; /* Set cc to (%r2 != 0) */ \
+ br %r6; /* Return */
-sk_load_word_slow:
- lgr %r9,%r2 # save %r2
- lgr %r3,%r1 # offset
- la %r4,160(%r15) # pointer to temp buffer
- lghi %r5,4 # 4 bytes
- brasl %r14,skb_copy_bits # get data from skb
- l %r5,160(%r15) # load result from temp buffer
- ltgr %r2,%r2 # set cc to (%r2 != 0)
- lgr %r2,%r9 # restore %r2
- br %r8
+sk_load_common(word, 4, llgf) /* r14 = *(u32 *) (skb->data+offset) */
+sk_load_common(half, 2, llgh) /* r14 = *(u16 *) (skb->data+offset) */
- /* A = *(u16 *) (skb->data+K+X) */
-ENTRY(sk_load_half_ind)
- ar %r3,%r12 # offset += X
- bmr %r8 # < 0 -> return with cc
-
- /* A = *(u16 *) (skb->data+K) */
-ENTRY(sk_load_half)
- llgfr %r1,%r3 # extend offset
- ahi %r3,2 # offset + 2
- clr %r11,%r3 # hlen <= offset + 2 ?
- jl sk_load_half_slow
- llgh %r5,0(%r1,%r10) # get half from skb
- xr %r1,%r1 # set cc to zero
- br %r8
-
-sk_load_half_slow:
- lgr %r9,%r2 # save %r2
- lgr %r3,%r1 # offset
- la %r4,162(%r15) # pointer to temp buffer
- lghi %r5,2 # 2 bytes
- brasl %r14,skb_copy_bits # get data from skb
- xc 160(2,%r15),160(%r15)
- l %r5,160(%r15) # load result from temp buffer
- ltgr %r2,%r2 # set cc to (%r2 != 0)
- lgr %r2,%r9 # restore %r2
- br %r8
-
- /* A = *(u8 *) (skb->data+K+X) */
-ENTRY(sk_load_byte_ind)
- ar %r3,%r12 # offset += X
- bmr %r8 # < 0 -> return with cc
-
- /* A = *(u8 *) (skb->data+K) */
+/*
+ * Load 1 byte from SKB (optimized version)
+ */
+ /* r14 = *(u8 *) (skb->data+offset) */
ENTRY(sk_load_byte)
- llgfr %r1,%r3 # extend offset
- clr %r11,%r3 # hlen < offset ?
- jle sk_load_byte_slow
- lhi %r5,0
- ic %r5,0(%r1,%r10) # get byte from skb
- xr %r1,%r1 # set cc to zero
- br %r8
+ ltgr %r3,%r3 # Is offset negative?
+ jl sk_load_byte_slow_neg
+ENTRY(sk_load_byte_pos)
+ clg %r3,STK_OFF_HLEN(%r15) # Offset >= hlen?
+ jnl sk_load_byte_slow
+ llgc %r14,0(%r3,%r12) # Get byte from skb
+ b OFF_OK(%r6) # Return OK
sk_load_byte_slow:
- lgr %r9,%r2 # save %r2
- lgr %r3,%r1 # offset
- la %r4,163(%r15) # pointer to temp buffer
- lghi %r5,1 # 1 byte
- brasl %r14,skb_copy_bits # get data from skb
- xc 160(3,%r15),160(%r15)
- l %r5,160(%r15) # load result from temp buffer
- ltgr %r2,%r2 # set cc to (%r2 != 0)
- lgr %r2,%r9 # restore %r2
- br %r8
+ lgr %r2,%r7 # Arg1 = skb pointer
+ # Arg2 = offset
+ la %r4,STK_OFF_TMP(%r15) # Arg3 = pointer to temp buffer
+ lghi %r5,1 # Arg4 = size (1 byte)
+ brasl %r14,skb_copy_bits # Get data from skb
+ llgc %r14,STK_OFF_TMP(%r15) # Load result from temp buffer
+ ltgr %r2,%r2 # Set cc to (%r2 != 0)
+ br %r6 # Return cc
- /* X = (*(u8 *)(skb->data+K) & 0xf) << 2 */
-ENTRY(sk_load_byte_msh)
- llgfr %r1,%r3 # extend offset
- clr %r11,%r3 # hlen < offset ?
- jle sk_load_byte_msh_slow
- lhi %r12,0
- ic %r12,0(%r1,%r10) # get byte from skb
- nill %r12,0x0f
- sll %r12,2
- xr %r1,%r1 # set cc to zero
- br %r8
+#define sk_negative_common(NAME, SIZE, LOAD) \
+sk_load_##NAME##_slow_neg:; \
+ cgfi %r3,SKF_MAX_NEG_OFF; \
+ jl bpf_error; \
+ lgr %r2,%r7; /* Arg1 = skb pointer */ \
+ /* Arg2 = offset */ \
+ lghi %r4,SIZE; /* Arg3 = size */ \
+ brasl %r14,bpf_internal_load_pointer_neg_helper; \
+ ltgr %r2,%r2; \
+ jz bpf_error; \
+ LOAD %r14,0(%r2); /* Get data from pointer */ \
+ xr %r3,%r3; /* Set cc to zero */ \
+ br %r6; /* Return cc */
-sk_load_byte_msh_slow:
- lgr %r9,%r2 # save %r2
- lgr %r3,%r1 # offset
- la %r4,163(%r15) # pointer to temp buffer
- lghi %r5,1 # 1 byte
- brasl %r14,skb_copy_bits # get data from skb
- xc 160(3,%r15),160(%r15)
- l %r12,160(%r15) # load result from temp buffer
- nill %r12,0x0f
- sll %r12,2
- ltgr %r2,%r2 # set cc to (%r2 != 0)
- lgr %r2,%r9 # restore %r2
- br %r8
+sk_negative_common(word, 4, llgf)
+sk_negative_common(half, 2, llgh)
+sk_negative_common(byte, 1, llgc)
+
+bpf_error:
+# force a return 0 from jit handler
+ ltgr %r15,%r15 # Set condition code
+ br %r6
diff --git a/arch/s390/net/bpf_jit.h b/arch/s390/net/bpf_jit.h
new file mode 100644
index 0000000..ba8593a5
--- /dev/null
+++ b/arch/s390/net/bpf_jit.h
@@ -0,0 +1,58 @@
+/*
+ * BPF Jit compiler defines
+ *
+ * Copyright IBM Corp. 2012,2015
+ *
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ * Michael Holzheu <holzheu@linux.vnet.ibm.com>
+ */
+
+#ifndef __ARCH_S390_NET_BPF_JIT_H
+#define __ARCH_S390_NET_BPF_JIT_H
+
+#ifndef __ASSEMBLY__
+
+#include <linux/filter.h>
+#include <linux/types.h>
+
+extern u8 sk_load_word_pos[], sk_load_half_pos[], sk_load_byte_pos[];
+extern u8 sk_load_word[], sk_load_half[], sk_load_byte[];
+
+#endif /* __ASSEMBLY__ */
+
+/*
+ * Stackframe layout (packed stack):
+ *
+ * ^ high
+ * +---------------+ |
+ * | old backchain | |
+ * +---------------+ |
+ * | r15 - r6 | |
+ * BFP -> +===============+ |
+ * | | |
+ * | BPF stack | |
+ * | | |
+ * +---------------+ |
+ * | 8 byte hlen | |
+ * R15+168 -> +---------------+ |
+ * | 4 byte align | |
+ * +---------------+ |
+ * | 4 byte temp | |
+ * | for bpf_jit.S | |
+ * R15+160 -> +---------------+ |
+ * | new backchain | |
+ * R15+152 -> +---------------+ |
+ * | + 152 byte SA | |
+ * R15 -> +---------------+ + low
+ *
+ * We get 160 bytes stack space from calling function, but only use
+ * 11 * 8 byte (old backchain + r15 - r6) for storing registers.
+ */
+#define STK_OFF (MAX_BPF_STACK + 8 + 4 + 4 + (160 - 11 * 8))
+#define STK_OFF_TMP 160 /* Offset of tmp buffer on stack */
+#define STK_OFF_HLEN 168 /* Offset of SKB header length on stack */
+
+/* Offset to skip condition code check */
+#define OFF_OK 4
+
+#endif /* __ARCH_S390_NET_BPF_JIT_H */
diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index bbd1981..7690dc8 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -1,817 +1,1209 @@
/*
* BPF Jit compiler for s390.
*
- * Copyright IBM Corp. 2012
+ * Minimum build requirements:
+ *
+ * - HAVE_MARCH_Z196_FEATURES: laal, laalg
+ * - HAVE_MARCH_Z10_FEATURES: msfi, cgrj, clgrj
+ * - HAVE_MARCH_Z9_109_FEATURES: alfi, llilf, clfi, oilf, nilf
+ * - PACK_STACK
+ * - 64BIT
+ *
+ * Copyright IBM Corp. 2012,2015
*
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ * Michael Holzheu <holzheu@linux.vnet.ibm.com>
*/
+
+#define KMSG_COMPONENT "bpf_jit"
+#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
+
#include <linux/netdevice.h>
-#include <linux/if_vlan.h>
#include <linux/filter.h>
#include <linux/init.h>
#include <asm/cacheflush.h>
-#include <asm/facility.h>
#include <asm/dis.h>
+#include "bpf_jit.h"
-/*
- * Conventions:
- * %r2 = skb pointer
- * %r3 = offset parameter
- * %r4 = scratch register / length parameter
- * %r5 = BPF A accumulator
- * %r8 = return address
- * %r9 = save register for skb pointer
- * %r10 = skb->data
- * %r11 = skb->len - skb->data_len (headlen)
- * %r12 = BPF X accumulator
- * %r13 = literal pool pointer
- * 0(%r15) - 63(%r15) scratch memory array with BPF_MEMWORDS
- */
int bpf_jit_enable __read_mostly;
-/*
- * assembly code in arch/x86/net/bpf_jit.S
- */
-extern u8 sk_load_word[], sk_load_half[], sk_load_byte[], sk_load_byte_msh[];
-extern u8 sk_load_word_ind[], sk_load_half_ind[], sk_load_byte_ind[];
-
struct bpf_jit {
- unsigned int seen;
- u8 *start;
- u8 *prg;
- u8 *mid;
- u8 *lit;
- u8 *end;
- u8 *base_ip;
- u8 *ret0_ip;
- u8 *exit_ip;
- unsigned int off_load_word;
- unsigned int off_load_half;
- unsigned int off_load_byte;
- unsigned int off_load_bmsh;
- unsigned int off_load_iword;
- unsigned int off_load_ihalf;
- unsigned int off_load_ibyte;
+ u32 seen; /* Flags to remember seen eBPF instructions */
+ u32 seen_reg[16]; /* Array to remember which registers are used */
+ u32 *addrs; /* Array with relative instruction addresses */
+ u8 *prg_buf; /* Start of program */
+ int size; /* Size of program and literal pool */
+ int size_prg; /* Size of program */
+ int prg; /* Current position in program */
+ int lit_start; /* Start of literal pool */
+ int lit; /* Current position in literal pool */
+ int base_ip; /* Base address for literal pool */
+ int ret0_ip; /* Address of return 0 */
+ int exit_ip; /* Address of exit */
};
#define BPF_SIZE_MAX 4096 /* Max size for program */
-#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 SEEN_RET0 8 /* pc_ret0 points to a valid return 0 */
-#define SEEN_LITERAL 16 /* code uses literals */
-#define SEEN_LOAD_WORD 32 /* code uses sk_load_word */
-#define SEEN_LOAD_HALF 64 /* code uses sk_load_half */
-#define SEEN_LOAD_BYTE 128 /* code uses sk_load_byte */
-#define SEEN_LOAD_BMSH 256 /* code uses sk_load_byte_msh */
-#define SEEN_LOAD_IWORD 512 /* code uses sk_load_word_ind */
-#define SEEN_LOAD_IHALF 1024 /* code uses sk_load_half_ind */
-#define SEEN_LOAD_IBYTE 2048 /* code uses sk_load_byte_ind */
+#define SEEN_SKB 1 /* skb access */
+#define SEEN_MEM 2 /* use mem[] for temporary storage */
+#define SEEN_RET0 4 /* ret0_ip points to a valid return 0 */
+#define SEEN_LITERAL 8 /* code uses literals */
+#define SEEN_FUNC 16 /* calls C functions */
+#define SEEN_STACK (SEEN_FUNC | SEEN_MEM | SEEN_SKB)
-#define EMIT2(op) \
-({ \
- if (jit->prg + 2 <= jit->mid) \
- *(u16 *) jit->prg = op; \
- jit->prg += 2; \
-})
+/*
+ * s390 registers
+ */
+#define REG_W0 (__MAX_BPF_REG+0) /* Work register 1 (even) */
+#define REG_W1 (__MAX_BPF_REG+1) /* Work register 2 (odd) */
+#define REG_SKB_DATA (__MAX_BPF_REG+2) /* SKB data register */
+#define REG_L (__MAX_BPF_REG+3) /* Literal pool register */
+#define REG_15 (__MAX_BPF_REG+4) /* Register 15 */
+#define REG_0 REG_W0 /* Register 0 */
+#define REG_2 BPF_REG_1 /* Register 2 */
+#define REG_14 BPF_REG_0 /* Register 14 */
-#define EMIT4(op) \
-({ \
- if (jit->prg + 4 <= jit->mid) \
- *(u32 *) jit->prg = op; \
- jit->prg += 4; \
-})
+/*
+ * Mapping of BPF registers to s390 registers
+ */
+static const int reg2hex[] = {
+ /* Return code */
+ [BPF_REG_0] = 14,
+ /* Function parameters */
+ [BPF_REG_1] = 2,
+ [BPF_REG_2] = 3,
+ [BPF_REG_3] = 4,
+ [BPF_REG_4] = 5,
+ [BPF_REG_5] = 6,
+ /* Call saved registers */
+ [BPF_REG_6] = 7,
+ [BPF_REG_7] = 8,
+ [BPF_REG_8] = 9,
+ [BPF_REG_9] = 10,
+ /* BPF stack pointer */
+ [BPF_REG_FP] = 13,
+ /* SKB data pointer */
+ [REG_SKB_DATA] = 12,
+ /* Work registers for s390x backend */
+ [REG_W0] = 0,
+ [REG_W1] = 1,
+ [REG_L] = 11,
+ [REG_15] = 15,
+};
-#define EMIT4_DISP(op, disp) \
-({ \
- unsigned int __disp = (disp) & 0xfff; \
- EMIT4(op | __disp); \
-})
-
-#define EMIT4_IMM(op, imm) \
-({ \
- unsigned int __imm = (imm) & 0xffff; \
- EMIT4(op | __imm); \
-})
-
-#define EMIT4_PCREL(op, pcrel) \
-({ \
- long __pcrel = ((pcrel) >> 1) & 0xffff; \
- EMIT4(op | __pcrel); \
-})
-
-#define EMIT6(op1, op2) \
-({ \
- if (jit->prg + 6 <= jit->mid) { \
- *(u32 *) jit->prg = op1; \
- *(u16 *) (jit->prg + 4) = op2; \
- } \
- jit->prg += 6; \
-})
-
-#define EMIT6_DISP(op1, op2, disp) \
-({ \
- unsigned int __disp = (disp) & 0xfff; \
- EMIT6(op1 | __disp, op2); \
-})
-
-#define EMIT6_IMM(op, imm) \
-({ \
- unsigned int __imm = (imm); \
- EMIT6(op | (__imm >> 16), __imm & 0xffff); \
-})
-
-#define EMIT_CONST(val) \
-({ \
- unsigned int ret; \
- ret = (unsigned int) (jit->lit - jit->base_ip); \
- jit->seen |= SEEN_LITERAL; \
- if (jit->lit + 4 <= jit->end) \
- *(u32 *) jit->lit = val; \
- jit->lit += 4; \
- ret; \
-})
-
-#define EMIT_FN_CONST(bit, fn) \
-({ \
- unsigned int ret; \
- ret = (unsigned int) (jit->lit - jit->base_ip); \
- if (jit->seen & bit) { \
- jit->seen |= SEEN_LITERAL; \
- if (jit->lit + 8 <= jit->end) \
- *(void **) jit->lit = fn; \
- jit->lit += 8; \
- } \
- ret; \
-})
-
-static void bpf_jit_fill_hole(void *area, unsigned int size)
+static inline u32 reg(u32 dst_reg, u32 src_reg)
{
- /* Fill whole space with illegal instructions */
+ return reg2hex[dst_reg] << 4 | reg2hex[src_reg];
+}
+
+static inline u32 reg_high(u32 reg)
+{
+ return reg2hex[reg] << 4;
+}
+
+static inline void reg_set_seen(struct bpf_jit *jit, u32 b1)
+{
+ u32 r1 = reg2hex[b1];
+
+ if (!jit->seen_reg[r1] && r1 >= 6 && r1 <= 15)
+ jit->seen_reg[r1] = 1;
+}
+
+#define REG_SET_SEEN(b1) \
+({ \
+ reg_set_seen(jit, b1); \
+})
+
+#define REG_SEEN(b1) jit->seen_reg[reg2hex[(b1)]]
+
+/*
+ * EMIT macros for code generation
+ */
+
+#define _EMIT2(op) \
+({ \
+ if (jit->prg_buf) \
+ *(u16 *) (jit->prg_buf + jit->prg) = op; \
+ jit->prg += 2; \
+})
+
+#define EMIT2(op, b1, b2) \
+({ \
+ _EMIT2(op | reg(b1, b2)); \
+ REG_SET_SEEN(b1); \
+ REG_SET_SEEN(b2); \
+})
+
+#define _EMIT4(op) \
+({ \
+ if (jit->prg_buf) \
+ *(u32 *) (jit->prg_buf + jit->prg) = op; \
+ jit->prg += 4; \
+})
+
+#define EMIT4(op, b1, b2) \
+({ \
+ _EMIT4(op | reg(b1, b2)); \
+ REG_SET_SEEN(b1); \
+ REG_SET_SEEN(b2); \
+})
+
+#define EMIT4_RRF(op, b1, b2, b3) \
+({ \
+ _EMIT4(op | reg_high(b3) << 8 | reg(b1, b2)); \
+ REG_SET_SEEN(b1); \
+ REG_SET_SEEN(b2); \
+ REG_SET_SEEN(b3); \
+})
+
+#define _EMIT4_DISP(op, disp) \
+({ \
+ unsigned int __disp = (disp) & 0xfff; \
+ _EMIT4(op | __disp); \
+})
+
+#define EMIT4_DISP(op, b1, b2, disp) \
+({ \
+ _EMIT4_DISP(op | reg_high(b1) << 16 | \
+ reg_high(b2) << 8, disp); \
+ REG_SET_SEEN(b1); \
+ REG_SET_SEEN(b2); \
+})
+
+#define EMIT4_IMM(op, b1, imm) \
+({ \
+ unsigned int __imm = (imm) & 0xffff; \
+ _EMIT4(op | reg_high(b1) << 16 | __imm); \
+ REG_SET_SEEN(b1); \
+})
+
+#define EMIT4_PCREL(op, pcrel) \
+({ \
+ long __pcrel = ((pcrel) >> 1) & 0xffff; \
+ _EMIT4(op | __pcrel); \
+})
+
+#define _EMIT6(op1, op2) \
+({ \
+ if (jit->prg_buf) { \
+ *(u32 *) (jit->prg_buf + jit->prg) = op1; \
+ *(u16 *) (jit->prg_buf + jit->prg + 4) = op2; \
+ } \
+ jit->prg += 6; \
+})
+
+#define _EMIT6_DISP(op1, op2, disp) \
+({ \
+ unsigned int __disp = (disp) & 0xfff; \
+ _EMIT6(op1 | __disp, op2); \
+})
+
+#define EMIT6_DISP(op1, op2, b1, b2, b3, disp) \
+({ \
+ _EMIT6_DISP(op1 | reg(b1, b2) << 16 | \
+ reg_high(b3) << 8, op2, disp); \
+ REG_SET_SEEN(b1); \
+ REG_SET_SEEN(b2); \
+ REG_SET_SEEN(b3); \
+})
+
+#define _EMIT6_DISP_LH(op1, op2, disp) \
+({ \
+ unsigned int __disp_h = ((u32)disp) & 0xff000; \
+ unsigned int __disp_l = ((u32)disp) & 0x00fff; \
+ _EMIT6(op1 | __disp_l, op2 | __disp_h >> 4); \
+})
+
+#define EMIT6_DISP_LH(op1, op2, b1, b2, b3, disp) \
+({ \
+ _EMIT6_DISP_LH(op1 | reg(b1, b2) << 16 | \
+ reg_high(b3) << 8, op2, disp); \
+ REG_SET_SEEN(b1); \
+ REG_SET_SEEN(b2); \
+ REG_SET_SEEN(b3); \
+})
+
+#define EMIT6_PCREL(op1, op2, b1, b2, i, off, mask) \
+({ \
+ /* Branch instruction needs 6 bytes */ \
+ int rel = (addrs[i + off + 1] - (addrs[i + 1] - 6)) / 2;\
+ _EMIT6(op1 | reg(b1, b2) << 16 | rel, op2 | mask); \
+ REG_SET_SEEN(b1); \
+ REG_SET_SEEN(b2); \
+})
+
+#define _EMIT6_IMM(op, imm) \
+({ \
+ unsigned int __imm = (imm); \
+ _EMIT6(op | (__imm >> 16), __imm & 0xffff); \
+})
+
+#define EMIT6_IMM(op, b1, imm) \
+({ \
+ _EMIT6_IMM(op | reg_high(b1) << 16, imm); \
+ REG_SET_SEEN(b1); \
+})
+
+#define EMIT_CONST_U32(val) \
+({ \
+ unsigned int ret; \
+ ret = jit->lit - jit->base_ip; \
+ jit->seen |= SEEN_LITERAL; \
+ if (jit->prg_buf) \
+ *(u32 *) (jit->prg_buf + jit->lit) = (u32) val; \
+ jit->lit += 4; \
+ ret; \
+})
+
+#define EMIT_CONST_U64(val) \
+({ \
+ unsigned int ret; \
+ ret = jit->lit - jit->base_ip; \
+ jit->seen |= SEEN_LITERAL; \
+ if (jit->prg_buf) \
+ *(u64 *) (jit->prg_buf + jit->lit) = (u64) val; \
+ jit->lit += 8; \
+ ret; \
+})
+
+#define EMIT_ZERO(b1) \
+({ \
+ /* llgfr %dst,%dst (zero extend to 64 bit) */ \
+ EMIT4(0xb9160000, b1, b1); \
+ REG_SET_SEEN(b1); \
+})
+
+/*
+ * Fill whole space with illegal instructions
+ */
+static void jit_fill_hole(void *area, unsigned int size)
+{
memset(area, 0, size);
}
+/*
+ * Save registers from "rs" (register start) to "re" (register end) on stack
+ */
+static void save_regs(struct bpf_jit *jit, u32 rs, u32 re)
+{
+ u32 off = 72 + (rs - 6) * 8;
+
+ if (rs == re)
+ /* stg %rs,off(%r15) */
+ _EMIT6(0xe300f000 | rs << 20 | off, 0x0024);
+ else
+ /* stmg %rs,%re,off(%r15) */
+ _EMIT6_DISP(0xeb00f000 | rs << 20 | re << 16, 0x0024, off);
+}
+
+/*
+ * Restore registers from "rs" (register start) to "re" (register end) on stack
+ */
+static void restore_regs(struct bpf_jit *jit, u32 rs, u32 re)
+{
+ u32 off = 72 + (rs - 6) * 8;
+
+ if (jit->seen & SEEN_STACK)
+ off += STK_OFF;
+
+ if (rs == re)
+ /* lg %rs,off(%r15) */
+ _EMIT6(0xe300f000 | rs << 20 | off, 0x0004);
+ else
+ /* lmg %rs,%re,off(%r15) */
+ _EMIT6_DISP(0xeb00f000 | rs << 20 | re << 16, 0x0004, off);
+}
+
+/*
+ * Return first seen register (from start)
+ */
+static int get_start(struct bpf_jit *jit, int start)
+{
+ int i;
+
+ for (i = start; i <= 15; i++) {
+ if (jit->seen_reg[i])
+ return i;
+ }
+ return 0;
+}
+
+/*
+ * Return last seen register (from start) (gap >= 2)
+ */
+static int get_end(struct bpf_jit *jit, int start)
+{
+ int i;
+
+ for (i = start; i < 15; i++) {
+ if (!jit->seen_reg[i] && !jit->seen_reg[i + 1])
+ return i - 1;
+ }
+ return jit->seen_reg[15] ? 15 : 14;
+}
+
+#define REGS_SAVE 1
+#define REGS_RESTORE 0
+/*
+ * Save and restore clobbered registers (6-15) on stack.
+ * We save/restore registers in chunks with gap >= 2 registers.
+ */
+static void save_restore_regs(struct bpf_jit *jit, int op)
+{
+
+ int re = 6, rs;
+
+ do {
+ rs = get_start(jit, re);
+ if (!rs)
+ break;
+ re = get_end(jit, rs + 1);
+ if (op == REGS_SAVE)
+ save_regs(jit, rs, re);
+ else
+ restore_regs(jit, rs, re);
+ re++;
+ } while (re <= 15);
+}
+
+/*
+ * Emit function prologue
+ *
+ * Save registers and create stack frame if necessary.
+ * See stack frame layout desription in "bpf_jit.h"!
+ */
static void bpf_jit_prologue(struct bpf_jit *jit)
{
- /* Save registers and create stack frame if necessary */
- if (jit->seen & SEEN_DATAREF) {
- /* stmg %r8,%r15,88(%r15) */
- EMIT6(0xeb8ff058, 0x0024);
- /* lgr %r14,%r15 */
- EMIT4(0xb90400ef);
- /* aghi %r15,<offset> */
- EMIT4_IMM(0xa7fb0000, (jit->seen & SEEN_MEM) ? -112 : -80);
- /* stg %r14,152(%r15) */
- EMIT6(0xe3e0f098, 0x0024);
- } else if ((jit->seen & SEEN_XREG) && (jit->seen & SEEN_LITERAL))
- /* stmg %r12,%r13,120(%r15) */
- EMIT6(0xebcdf078, 0x0024);
- else if (jit->seen & SEEN_XREG)
- /* stg %r12,120(%r15) */
- EMIT6(0xe3c0f078, 0x0024);
- else if (jit->seen & SEEN_LITERAL)
- /* stg %r13,128(%r15) */
- EMIT6(0xe3d0f080, 0x0024);
-
+ /* Save registers */
+ save_restore_regs(jit, REGS_SAVE);
/* Setup literal pool */
if (jit->seen & SEEN_LITERAL) {
/* basr %r13,0 */
- EMIT2(0x0dd0);
+ EMIT2(0x0d00, REG_L, REG_0);
jit->base_ip = jit->prg;
}
- jit->off_load_word = EMIT_FN_CONST(SEEN_LOAD_WORD, sk_load_word);
- jit->off_load_half = EMIT_FN_CONST(SEEN_LOAD_HALF, sk_load_half);
- jit->off_load_byte = EMIT_FN_CONST(SEEN_LOAD_BYTE, sk_load_byte);
- jit->off_load_bmsh = EMIT_FN_CONST(SEEN_LOAD_BMSH, sk_load_byte_msh);
- jit->off_load_iword = EMIT_FN_CONST(SEEN_LOAD_IWORD, sk_load_word_ind);
- jit->off_load_ihalf = EMIT_FN_CONST(SEEN_LOAD_IHALF, sk_load_half_ind);
- jit->off_load_ibyte = EMIT_FN_CONST(SEEN_LOAD_IBYTE, sk_load_byte_ind);
-
- /* Filter needs to access skb data */
- if (jit->seen & SEEN_DATAREF) {
- /* l %r11,<len>(%r2) */
- EMIT4_DISP(0x58b02000, offsetof(struct sk_buff, len));
- /* s %r11,<data_len>(%r2) */
- EMIT4_DISP(0x5bb02000, offsetof(struct sk_buff, data_len));
- /* lg %r10,<data>(%r2) */
- EMIT6_DISP(0xe3a02000, 0x0004,
- offsetof(struct sk_buff, data));
+ /* Setup stack and backchain */
+ if (jit->seen & SEEN_STACK) {
+ /* lgr %bfp,%r15 (BPF frame pointer) */
+ EMIT4(0xb9040000, BPF_REG_FP, REG_15);
+ /* aghi %r15,-STK_OFF */
+ EMIT4_IMM(0xa70b0000, REG_15, -STK_OFF);
+ if (jit->seen & SEEN_FUNC)
+ /* stg %bfp,152(%r15) (backchain) */
+ EMIT6_DISP_LH(0xe3000000, 0x0024, BPF_REG_FP, REG_0,
+ REG_15, 152);
}
+ /*
+ * For SKB access %b1 contains the SKB pointer. For "bpf_jit.S"
+ * we store the SKB header length on the stack and the SKB data
+ * pointer in REG_SKB_DATA.
+ */
+ if (jit->seen & SEEN_SKB) {
+ /* Header length: llgf %w1,<len>(%b1) */
+ EMIT6_DISP_LH(0xe3000000, 0x0016, REG_W1, REG_0, BPF_REG_1,
+ offsetof(struct sk_buff, len));
+ /* s %w1,<data_len>(%b1) */
+ EMIT4_DISP(0x5b000000, REG_W1, BPF_REG_1,
+ offsetof(struct sk_buff, data_len));
+ /* stg %w1,ST_OFF_HLEN(%r0,%r15) */
+ EMIT6_DISP_LH(0xe3000000, 0x0024, REG_W1, REG_0, REG_15,
+ STK_OFF_HLEN);
+ /* lg %skb_data,data_off(%b1) */
+ EMIT6_DISP_LH(0xe3000000, 0x0004, REG_SKB_DATA, REG_0,
+ BPF_REG_1, offsetof(struct sk_buff, data));
+ }
+ /* BPF compatibility: clear A (%b7) and X (%b8) registers */
+ if (REG_SEEN(BPF_REG_7))
+ /* lghi %b7,0 */
+ EMIT4_IMM(0xa7090000, BPF_REG_7, 0);
+ if (REG_SEEN(BPF_REG_8))
+ /* lghi %b8,0 */
+ EMIT4_IMM(0xa7090000, BPF_REG_8, 0);
}
+/*
+ * Function epilogue
+ */
static void bpf_jit_epilogue(struct bpf_jit *jit)
{
/* Return 0 */
if (jit->seen & SEEN_RET0) {
jit->ret0_ip = jit->prg;
- /* lghi %r2,0 */
- EMIT4(0xa7290000);
+ /* lghi %b0,0 */
+ EMIT4_IMM(0xa7090000, BPF_REG_0, 0);
}
jit->exit_ip = jit->prg;
+ /* Load exit code: lgr %r2,%b0 */
+ EMIT4(0xb9040000, REG_2, BPF_REG_0);
/* Restore registers */
- if (jit->seen & SEEN_DATAREF)
- /* lmg %r8,%r15,<offset>(%r15) */
- EMIT6_DISP(0xeb8ff000, 0x0004,
- (jit->seen & SEEN_MEM) ? 200 : 168);
- else if ((jit->seen & SEEN_XREG) && (jit->seen & SEEN_LITERAL))
- /* lmg %r12,%r13,120(%r15) */
- EMIT6(0xebcdf078, 0x0004);
- else if (jit->seen & SEEN_XREG)
- /* lg %r12,120(%r15) */
- EMIT6(0xe3c0f078, 0x0004);
- else if (jit->seen & SEEN_LITERAL)
- /* lg %r13,128(%r15) */
- EMIT6(0xe3d0f080, 0x0004);
+ save_restore_regs(jit, REGS_RESTORE);
/* br %r14 */
- EMIT2(0x07fe);
+ _EMIT2(0x07fe);
}
/*
- * make sure we dont leak kernel information to user
+ * Compile one eBPF instruction into s390x code
*/
-static void bpf_jit_noleaks(struct bpf_jit *jit, struct sock_filter *filter)
+static int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp, int i)
{
- /* Clear temporary memory if (seen & SEEN_MEM) */
- if (jit->seen & SEEN_MEM)
- /* xc 0(64,%r15),0(%r15) */
- EMIT6(0xd73ff000, 0xf000);
- /* Clear X if (seen & SEEN_XREG) */
- if (jit->seen & SEEN_XREG)
- /* lhi %r12,0 */
- EMIT4(0xa7c80000);
- /* Clear A if the first register does not set it. */
- switch (filter[0].code) {
- case BPF_LD | BPF_W | BPF_ABS:
- case BPF_LD | BPF_H | BPF_ABS:
- case BPF_LD | BPF_B | BPF_ABS:
- case BPF_LD | BPF_W | BPF_LEN:
- case BPF_LD | BPF_W | BPF_IND:
- case BPF_LD | BPF_H | BPF_IND:
- case BPF_LD | BPF_B | BPF_IND:
- case BPF_LD | BPF_IMM:
- case BPF_LD | BPF_MEM:
- case BPF_MISC | BPF_TXA:
- case BPF_RET | BPF_K:
- /* first instruction sets A register */
+ struct bpf_insn *insn = &fp->insnsi[i];
+ int jmp_off, last, insn_count = 1;
+ unsigned int func_addr, mask;
+ u32 dst_reg = insn->dst_reg;
+ u32 src_reg = insn->src_reg;
+ u32 *addrs = jit->addrs;
+ s32 imm = insn->imm;
+ s16 off = insn->off;
+
+ switch (insn->code) {
+ /*
+ * BPF_MOV
+ */
+ case BPF_ALU | BPF_MOV | BPF_X: /* dst = (u32) src */
+ /* llgfr %dst,%src */
+ EMIT4(0xb9160000, dst_reg, src_reg);
break;
- default: /* A = 0 */
- /* lhi %r5,0 */
- EMIT4(0xa7580000);
+ case BPF_ALU64 | BPF_MOV | BPF_X: /* dst = src */
+ /* lgr %dst,%src */
+ EMIT4(0xb9040000, dst_reg, src_reg);
+ break;
+ case BPF_ALU | BPF_MOV | BPF_K: /* dst = (u32) imm */
+ /* llilf %dst,imm */
+ EMIT6_IMM(0xc00f0000, dst_reg, imm);
+ break;
+ case BPF_ALU64 | BPF_MOV | BPF_K: /* dst = imm */
+ /* lgfi %dst,imm */
+ EMIT6_IMM(0xc0010000, dst_reg, imm);
+ break;
+ /*
+ * BPF_LD 64
+ */
+ case BPF_LD | BPF_IMM | BPF_DW: /* dst = (u64) imm */
+ {
+ /* 16 byte instruction that uses two 'struct bpf_insn' */
+ u64 imm64;
+
+ imm64 = (u64)(u32) insn[0].imm | ((u64)(u32) insn[1].imm) << 32;
+ /* lg %dst,<d(imm)>(%l) */
+ EMIT6_DISP_LH(0xe3000000, 0x0004, dst_reg, REG_0, REG_L,
+ EMIT_CONST_U64(imm64));
+ insn_count = 2;
+ break;
}
-}
+ /*
+ * BPF_ADD
+ */
+ case BPF_ALU | BPF_ADD | BPF_X: /* dst = (u32) dst + (u32) src */
+ /* ar %dst,%src */
+ EMIT2(0x1a00, dst_reg, src_reg);
+ EMIT_ZERO(dst_reg);
+ break;
+ case BPF_ALU64 | BPF_ADD | BPF_X: /* dst = dst + src */
+ /* agr %dst,%src */
+ EMIT4(0xb9080000, dst_reg, src_reg);
+ break;
+ case BPF_ALU | BPF_ADD | BPF_K: /* dst = (u32) dst + (u32) imm */
+ if (!imm)
+ break;
+ /* alfi %dst,imm */
+ EMIT6_IMM(0xc20b0000, dst_reg, imm);
+ EMIT_ZERO(dst_reg);
+ break;
+ case BPF_ALU64 | BPF_ADD | BPF_K: /* dst = dst + imm */
+ if (!imm)
+ break;
+ /* agfi %dst,imm */
+ EMIT6_IMM(0xc2080000, dst_reg, imm);
+ break;
+ /*
+ * BPF_SUB
+ */
+ case BPF_ALU | BPF_SUB | BPF_X: /* dst = (u32) dst - (u32) src */
+ /* sr %dst,%src */
+ EMIT2(0x1b00, dst_reg, src_reg);
+ EMIT_ZERO(dst_reg);
+ break;
+ case BPF_ALU64 | BPF_SUB | BPF_X: /* dst = dst - src */
+ /* sgr %dst,%src */
+ EMIT4(0xb9090000, dst_reg, src_reg);
+ break;
+ case BPF_ALU | BPF_SUB | BPF_K: /* dst = (u32) dst - (u32) imm */
+ if (!imm)
+ break;
+ /* alfi %dst,-imm */
+ EMIT6_IMM(0xc20b0000, dst_reg, -imm);
+ EMIT_ZERO(dst_reg);
+ break;
+ case BPF_ALU64 | BPF_SUB | BPF_K: /* dst = dst - imm */
+ if (!imm)
+ break;
+ /* agfi %dst,-imm */
+ EMIT6_IMM(0xc2080000, dst_reg, -imm);
+ break;
+ /*
+ * BPF_MUL
+ */
+ case BPF_ALU | BPF_MUL | BPF_X: /* dst = (u32) dst * (u32) src */
+ /* msr %dst,%src */
+ EMIT4(0xb2520000, dst_reg, src_reg);
+ EMIT_ZERO(dst_reg);
+ break;
+ case BPF_ALU64 | BPF_MUL | BPF_X: /* dst = dst * src */
+ /* msgr %dst,%src */
+ EMIT4(0xb90c0000, dst_reg, src_reg);
+ break;
+ case BPF_ALU | BPF_MUL | BPF_K: /* dst = (u32) dst * (u32) imm */
+ if (imm == 1)
+ break;
+ /* msfi %r5,imm */
+ EMIT6_IMM(0xc2010000, dst_reg, imm);
+ EMIT_ZERO(dst_reg);
+ break;
+ case BPF_ALU64 | BPF_MUL | BPF_K: /* dst = dst * imm */
+ if (imm == 1)
+ break;
+ /* msgfi %dst,imm */
+ EMIT6_IMM(0xc2000000, dst_reg, imm);
+ break;
+ /*
+ * BPF_DIV / BPF_MOD
+ */
+ case BPF_ALU | BPF_DIV | BPF_X: /* dst = (u32) dst / (u32) src */
+ case BPF_ALU | BPF_MOD | BPF_X: /* dst = (u32) dst % (u32) src */
+ {
+ int rc_reg = BPF_OP(insn->code) == BPF_DIV ? REG_W1 : REG_W0;
-static int bpf_jit_insn(struct bpf_jit *jit, struct sock_filter *filter,
- unsigned int *addrs, int i, int last)
-{
- unsigned int K;
- int offset;
- unsigned int mask;
- u16 code;
-
- K = filter->k;
- code = bpf_anc_helper(filter);
-
- switch (code) {
- case BPF_ALU | BPF_ADD | BPF_X: /* A += X */
- jit->seen |= SEEN_XREG;
- /* ar %r5,%r12 */
- EMIT2(0x1a5c);
- break;
- case BPF_ALU | BPF_ADD | BPF_K: /* A += K */
- if (!K)
- break;
- if (K <= 16383)
- /* ahi %r5,<K> */
- EMIT4_IMM(0xa75a0000, K);
- else if (test_facility(21))
- /* alfi %r5,<K> */
- EMIT6_IMM(0xc25b0000, K);
- else
- /* a %r5,<d(K)>(%r13) */
- EMIT4_DISP(0x5a50d000, EMIT_CONST(K));
- break;
- case BPF_ALU | BPF_SUB | BPF_X: /* A -= X */
- jit->seen |= SEEN_XREG;
- /* sr %r5,%r12 */
- EMIT2(0x1b5c);
- break;
- case BPF_ALU | BPF_SUB | BPF_K: /* A -= K */
- if (!K)
- break;
- if (K <= 16384)
- /* ahi %r5,-K */
- EMIT4_IMM(0xa75a0000, -K);
- else if (test_facility(21))
- /* alfi %r5,-K */
- EMIT6_IMM(0xc25b0000, -K);
- else
- /* s %r5,<d(K)>(%r13) */
- EMIT4_DISP(0x5b50d000, EMIT_CONST(K));
- break;
- case BPF_ALU | BPF_MUL | BPF_X: /* A *= X */
- jit->seen |= SEEN_XREG;
- /* msr %r5,%r12 */
- EMIT4(0xb252005c);
- break;
- case BPF_ALU | BPF_MUL | BPF_K: /* A *= K */
- if (K <= 16383)
- /* mhi %r5,K */
- EMIT4_IMM(0xa75c0000, K);
- else if (test_facility(34))
- /* msfi %r5,<K> */
- EMIT6_IMM(0xc2510000, K);
- else
- /* ms %r5,<d(K)>(%r13) */
- EMIT4_DISP(0x7150d000, EMIT_CONST(K));
- break;
- case BPF_ALU | BPF_DIV | BPF_X: /* A /= X */
- jit->seen |= SEEN_XREG | SEEN_RET0;
- /* ltr %r12,%r12 */
- EMIT2(0x12cc);
- /* jz <ret0> */
- EMIT4_PCREL(0xa7840000, (jit->ret0_ip - jit->prg));
- /* lhi %r4,0 */
- EMIT4(0xa7480000);
- /* dlr %r4,%r12 */
- EMIT4(0xb997004c);
- break;
- case BPF_ALU | BPF_DIV | BPF_K: /* A /= K */
- if (K == 1)
- break;
- /* lhi %r4,0 */
- EMIT4(0xa7480000);
- /* dl %r4,<d(K)>(%r13) */
- EMIT6_DISP(0xe340d000, 0x0097, EMIT_CONST(K));
- break;
- case BPF_ALU | BPF_MOD | BPF_X: /* A %= X */
- jit->seen |= SEEN_XREG | SEEN_RET0;
- /* ltr %r12,%r12 */
- EMIT2(0x12cc);
- /* jz <ret0> */
- EMIT4_PCREL(0xa7840000, (jit->ret0_ip - jit->prg));
- /* lhi %r4,0 */
- EMIT4(0xa7480000);
- /* dlr %r4,%r12 */
- EMIT4(0xb997004c);
- /* lr %r5,%r4 */
- EMIT2(0x1854);
- break;
- case BPF_ALU | BPF_MOD | BPF_K: /* A %= K */
- if (K == 1) {
- /* lhi %r5,0 */
- EMIT4(0xa7580000);
- break;
- }
- /* lhi %r4,0 */
- EMIT4(0xa7480000);
- /* dl %r4,<d(K)>(%r13) */
- EMIT6_DISP(0xe340d000, 0x0097, EMIT_CONST(K));
- /* lr %r5,%r4 */
- EMIT2(0x1854);
- break;
- case BPF_ALU | BPF_AND | BPF_X: /* A &= X */
- jit->seen |= SEEN_XREG;
- /* nr %r5,%r12 */
- EMIT2(0x145c);
- break;
- case BPF_ALU | BPF_AND | BPF_K: /* A &= K */
- if (test_facility(21))
- /* nilf %r5,<K> */
- EMIT6_IMM(0xc05b0000, K);
- else
- /* n %r5,<d(K)>(%r13) */
- EMIT4_DISP(0x5450d000, EMIT_CONST(K));
- break;
- case BPF_ALU | BPF_OR | BPF_X: /* A |= X */
- jit->seen |= SEEN_XREG;
- /* or %r5,%r12 */
- EMIT2(0x165c);
- break;
- case BPF_ALU | BPF_OR | BPF_K: /* A |= K */
- if (test_facility(21))
- /* oilf %r5,<K> */
- EMIT6_IMM(0xc05d0000, K);
- else
- /* o %r5,<d(K)>(%r13) */
- EMIT4_DISP(0x5650d000, EMIT_CONST(K));
- break;
- case BPF_ANC | SKF_AD_ALU_XOR_X: /* A ^= X; */
- case BPF_ALU | BPF_XOR | BPF_X:
- jit->seen |= SEEN_XREG;
- /* xr %r5,%r12 */
- EMIT2(0x175c);
- break;
- case BPF_ALU | BPF_XOR | BPF_K: /* A ^= K */
- if (!K)
- break;
- /* x %r5,<d(K)>(%r13) */
- EMIT4_DISP(0x5750d000, EMIT_CONST(K));
- break;
- case BPF_ALU | BPF_LSH | BPF_X: /* A <<= X; */
- jit->seen |= SEEN_XREG;
- /* sll %r5,0(%r12) */
- EMIT4(0x8950c000);
- break;
- case BPF_ALU | BPF_LSH | BPF_K: /* A <<= K */
- if (K == 0)
- break;
- /* sll %r5,K */
- EMIT4_DISP(0x89500000, K);
- break;
- case BPF_ALU | BPF_RSH | BPF_X: /* A >>= X; */
- jit->seen |= SEEN_XREG;
- /* srl %r5,0(%r12) */
- EMIT4(0x8850c000);
- break;
- case BPF_ALU | BPF_RSH | BPF_K: /* A >>= K; */
- if (K == 0)
- break;
- /* srl %r5,K */
- EMIT4_DISP(0x88500000, K);
- break;
- case BPF_ALU | BPF_NEG: /* A = -A */
- /* lcr %r5,%r5 */
- EMIT2(0x1355);
- break;
- case BPF_JMP | BPF_JA: /* ip += K */
- offset = addrs[i + K] + jit->start - jit->prg;
- EMIT4_PCREL(0xa7f40000, offset);
- break;
- case BPF_JMP | BPF_JGT | BPF_K: /* ip += (A > K) ? jt : jf */
- mask = 0x200000; /* jh */
- goto kbranch;
- case BPF_JMP | BPF_JGE | BPF_K: /* ip += (A >= K) ? jt : jf */
- mask = 0xa00000; /* jhe */
- goto kbranch;
- case BPF_JMP | BPF_JEQ | BPF_K: /* ip += (A == K) ? jt : jf */
- mask = 0x800000; /* je */
-kbranch: /* Emit compare if the branch targets are different */
- if (filter->jt != filter->jf) {
- if (test_facility(21))
- /* clfi %r5,<K> */
- EMIT6_IMM(0xc25f0000, K);
- else
- /* cl %r5,<d(K)>(%r13) */
- EMIT4_DISP(0x5550d000, EMIT_CONST(K));
- }
-branch: if (filter->jt == filter->jf) {
- if (filter->jt == 0)
- break;
- /* j <jt> */
- offset = addrs[i + filter->jt] + jit->start - jit->prg;
- EMIT4_PCREL(0xa7f40000, offset);
- break;
- }
- if (filter->jt != 0) {
- /* brc <mask>,<jt> */
- offset = addrs[i + filter->jt] + jit->start - jit->prg;
- EMIT4_PCREL(0xa7040000 | mask, offset);
- }
- if (filter->jf != 0) {
- /* brc <mask^15>,<jf> */
- offset = addrs[i + filter->jf] + jit->start - jit->prg;
- EMIT4_PCREL(0xa7040000 | (mask ^ 0xf00000), offset);
- }
- break;
- case BPF_JMP | BPF_JSET | BPF_K: /* ip += (A & K) ? jt : jf */
- mask = 0x700000; /* jnz */
- /* Emit test if the branch targets are different */
- if (filter->jt != filter->jf) {
- if (K > 65535) {
- /* lr %r4,%r5 */
- EMIT2(0x1845);
- /* n %r4,<d(K)>(%r13) */
- EMIT4_DISP(0x5440d000, EMIT_CONST(K));
- } else
- /* tmll %r5,K */
- EMIT4_IMM(0xa7510000, K);
- }
- goto branch;
- case BPF_JMP | BPF_JGT | BPF_X: /* ip += (A > X) ? jt : jf */
- mask = 0x200000; /* jh */
- goto xbranch;
- case BPF_JMP | BPF_JGE | BPF_X: /* ip += (A >= X) ? jt : jf */
- mask = 0xa00000; /* jhe */
- goto xbranch;
- case BPF_JMP | BPF_JEQ | BPF_X: /* ip += (A == X) ? jt : jf */
- mask = 0x800000; /* je */
-xbranch: /* Emit compare if the branch targets are different */
- if (filter->jt != filter->jf) {
- jit->seen |= SEEN_XREG;
- /* clr %r5,%r12 */
- EMIT2(0x155c);
- }
- goto branch;
- case BPF_JMP | BPF_JSET | BPF_X: /* ip += (A & X) ? jt : jf */
- mask = 0x700000; /* jnz */
- /* Emit test if the branch targets are different */
- if (filter->jt != filter->jf) {
- jit->seen |= SEEN_XREG;
- /* lr %r4,%r5 */
- EMIT2(0x1845);
- /* nr %r4,%r12 */
- EMIT2(0x144c);
- }
- goto branch;
- case BPF_LD | BPF_W | BPF_ABS: /* A = *(u32 *) (skb->data+K) */
- jit->seen |= SEEN_DATAREF | SEEN_RET0 | SEEN_LOAD_WORD;
- offset = jit->off_load_word;
- goto load_abs;
- case BPF_LD | BPF_H | BPF_ABS: /* A = *(u16 *) (skb->data+K) */
- jit->seen |= SEEN_DATAREF | SEEN_RET0 | SEEN_LOAD_HALF;
- offset = jit->off_load_half;
- goto load_abs;
- case BPF_LD | BPF_B | BPF_ABS: /* A = *(u8 *) (skb->data+K) */
- jit->seen |= SEEN_DATAREF | SEEN_RET0 | SEEN_LOAD_BYTE;
- offset = jit->off_load_byte;
-load_abs: if ((int) K < 0)
- goto out;
-call_fn: /* lg %r1,<d(function)>(%r13) */
- EMIT6_DISP(0xe310d000, 0x0004, offset);
- /* l %r3,<d(K)>(%r13) */
- EMIT4_DISP(0x5830d000, EMIT_CONST(K));
- /* basr %r8,%r1 */
- EMIT2(0x0d81);
- /* jnz <ret0> */
- EMIT4_PCREL(0xa7740000, (jit->ret0_ip - jit->prg));
- break;
- case BPF_LD | BPF_W | BPF_IND: /* A = *(u32 *) (skb->data+K+X) */
- jit->seen |= SEEN_DATAREF | SEEN_RET0 | SEEN_LOAD_IWORD;
- offset = jit->off_load_iword;
- goto call_fn;
- case BPF_LD | BPF_H | BPF_IND: /* A = *(u16 *) (skb->data+K+X) */
- jit->seen |= SEEN_DATAREF | SEEN_RET0 | SEEN_LOAD_IHALF;
- offset = jit->off_load_ihalf;
- goto call_fn;
- case BPF_LD | BPF_B | BPF_IND: /* A = *(u8 *) (skb->data+K+X) */
- jit->seen |= SEEN_DATAREF | SEEN_RET0 | SEEN_LOAD_IBYTE;
- offset = jit->off_load_ibyte;
- goto call_fn;
- case BPF_LDX | BPF_B | BPF_MSH:
- /* X = (*(u8 *)(skb->data+K) & 0xf) << 2 */
jit->seen |= SEEN_RET0;
- if ((int) K < 0) {
- /* j <ret0> */
- EMIT4_PCREL(0xa7f40000, (jit->ret0_ip - jit->prg));
+ /* ltr %src,%src (if src == 0 goto fail) */
+ EMIT2(0x1200, src_reg, src_reg);
+ /* jz <ret0> */
+ EMIT4_PCREL(0xa7840000, jit->ret0_ip - jit->prg);
+ /* lhi %w0,0 */
+ EMIT4_IMM(0xa7080000, REG_W0, 0);
+ /* lr %w1,%dst */
+ EMIT2(0x1800, REG_W1, dst_reg);
+ /* dlr %w0,%src */
+ EMIT4(0xb9970000, REG_W0, src_reg);
+ /* llgfr %dst,%rc */
+ EMIT4(0xb9160000, dst_reg, rc_reg);
+ break;
+ }
+ case BPF_ALU64 | BPF_DIV | BPF_X: /* dst = dst / (u32) src */
+ case BPF_ALU64 | BPF_MOD | BPF_X: /* dst = dst % (u32) src */
+ {
+ int rc_reg = BPF_OP(insn->code) == BPF_DIV ? REG_W1 : REG_W0;
+
+ jit->seen |= SEEN_RET0;
+ /* ltgr %src,%src (if src == 0 goto fail) */
+ EMIT4(0xb9020000, src_reg, src_reg);
+ /* jz <ret0> */
+ EMIT4_PCREL(0xa7840000, jit->ret0_ip - jit->prg);
+ /* lghi %w0,0 */
+ EMIT4_IMM(0xa7090000, REG_W0, 0);
+ /* lgr %w1,%dst */
+ EMIT4(0xb9040000, REG_W1, dst_reg);
+ /* llgfr %dst,%src (u32 cast) */
+ EMIT4(0xb9160000, dst_reg, src_reg);
+ /* dlgr %w0,%dst */
+ EMIT4(0xb9870000, REG_W0, dst_reg);
+ /* lgr %dst,%rc */
+ EMIT4(0xb9040000, dst_reg, rc_reg);
+ break;
+ }
+ case BPF_ALU | BPF_DIV | BPF_K: /* dst = (u32) dst / (u32) imm */
+ case BPF_ALU | BPF_MOD | BPF_K: /* dst = (u32) dst % (u32) imm */
+ {
+ int rc_reg = BPF_OP(insn->code) == BPF_DIV ? REG_W1 : REG_W0;
+
+ if (imm == 1) {
+ if (BPF_OP(insn->code) == BPF_MOD)
+ /* lhgi %dst,0 */
+ EMIT4_IMM(0xa7090000, dst_reg, 0);
break;
}
- jit->seen |= SEEN_DATAREF | SEEN_LOAD_BMSH;
- offset = jit->off_load_bmsh;
- goto call_fn;
- case BPF_LD | BPF_W | BPF_LEN: /* A = skb->len; */
- BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, len) != 4);
- /* l %r5,<d(len)>(%r2) */
- EMIT4_DISP(0x58502000, offsetof(struct sk_buff, len));
+ /* lhi %w0,0 */
+ EMIT4_IMM(0xa7080000, REG_W0, 0);
+ /* lr %w1,%dst */
+ EMIT2(0x1800, REG_W1, dst_reg);
+ /* dl %w0,<d(imm)>(%l) */
+ EMIT6_DISP_LH(0xe3000000, 0x0097, REG_W0, REG_0, REG_L,
+ EMIT_CONST_U32(imm));
+ /* llgfr %dst,%rc */
+ EMIT4(0xb9160000, dst_reg, rc_reg);
break;
- case BPF_LDX | BPF_W | BPF_LEN: /* X = skb->len; */
- jit->seen |= SEEN_XREG;
- /* l %r12,<d(len)>(%r2) */
- EMIT4_DISP(0x58c02000, offsetof(struct sk_buff, len));
+ }
+ case BPF_ALU64 | BPF_DIV | BPF_K: /* dst = dst / (u32) imm */
+ case BPF_ALU64 | BPF_MOD | BPF_K: /* dst = dst % (u32) imm */
+ {
+ int rc_reg = BPF_OP(insn->code) == BPF_DIV ? REG_W1 : REG_W0;
+
+ if (imm == 1) {
+ if (BPF_OP(insn->code) == BPF_MOD)
+ /* lhgi %dst,0 */
+ EMIT4_IMM(0xa7090000, dst_reg, 0);
+ break;
+ }
+ /* lghi %w0,0 */
+ EMIT4_IMM(0xa7090000, REG_W0, 0);
+ /* lgr %w1,%dst */
+ EMIT4(0xb9040000, REG_W1, dst_reg);
+ /* dlg %w0,<d(imm)>(%l) */
+ EMIT6_DISP_LH(0xe3000000, 0x0087, REG_W0, REG_0, REG_L,
+ EMIT_CONST_U64((u32) imm));
+ /* lgr %dst,%rc */
+ EMIT4(0xb9040000, dst_reg, rc_reg);
break;
- case BPF_LD | BPF_IMM: /* A = K */
- if (K <= 16383)
- /* lhi %r5,K */
- EMIT4_IMM(0xa7580000, K);
- else if (test_facility(21))
- /* llilf %r5,<K> */
- EMIT6_IMM(0xc05f0000, K);
- else
- /* l %r5,<d(K)>(%r13) */
- EMIT4_DISP(0x5850d000, EMIT_CONST(K));
+ }
+ /*
+ * BPF_AND
+ */
+ case BPF_ALU | BPF_AND | BPF_X: /* dst = (u32) dst & (u32) src */
+ /* nr %dst,%src */
+ EMIT2(0x1400, dst_reg, src_reg);
+ EMIT_ZERO(dst_reg);
break;
- case BPF_LDX | BPF_IMM: /* X = K */
- jit->seen |= SEEN_XREG;
- if (K <= 16383)
- /* lhi %r12,<K> */
- EMIT4_IMM(0xa7c80000, K);
- else if (test_facility(21))
- /* llilf %r12,<K> */
- EMIT6_IMM(0xc0cf0000, K);
- else
- /* l %r12,<d(K)>(%r13) */
- EMIT4_DISP(0x58c0d000, EMIT_CONST(K));
+ case BPF_ALU64 | BPF_AND | BPF_X: /* dst = dst & src */
+ /* ngr %dst,%src */
+ EMIT4(0xb9800000, dst_reg, src_reg);
break;
- case BPF_LD | BPF_MEM: /* A = mem[K] */
- jit->seen |= SEEN_MEM;
- /* l %r5,<K>(%r15) */
- EMIT4_DISP(0x5850f000,
- (jit->seen & SEEN_DATAREF) ? 160 + K*4 : K*4);
+ case BPF_ALU | BPF_AND | BPF_K: /* dst = (u32) dst & (u32) imm */
+ /* nilf %dst,imm */
+ EMIT6_IMM(0xc00b0000, dst_reg, imm);
+ EMIT_ZERO(dst_reg);
break;
- case BPF_LDX | BPF_MEM: /* X = mem[K] */
- jit->seen |= SEEN_XREG | SEEN_MEM;
- /* l %r12,<K>(%r15) */
- EMIT4_DISP(0x58c0f000,
- (jit->seen & SEEN_DATAREF) ? 160 + K*4 : K*4);
+ case BPF_ALU64 | BPF_AND | BPF_K: /* dst = dst & imm */
+ /* ng %dst,<d(imm)>(%l) */
+ EMIT6_DISP_LH(0xe3000000, 0x0080, dst_reg, REG_0, REG_L,
+ EMIT_CONST_U64(imm));
break;
- case BPF_MISC | BPF_TAX: /* X = A */
- jit->seen |= SEEN_XREG;
- /* lr %r12,%r5 */
- EMIT2(0x18c5);
+ /*
+ * BPF_OR
+ */
+ case BPF_ALU | BPF_OR | BPF_X: /* dst = (u32) dst | (u32) src */
+ /* or %dst,%src */
+ EMIT2(0x1600, dst_reg, src_reg);
+ EMIT_ZERO(dst_reg);
break;
- case BPF_MISC | BPF_TXA: /* A = X */
- jit->seen |= SEEN_XREG;
- /* lr %r5,%r12 */
- EMIT2(0x185c);
+ case BPF_ALU64 | BPF_OR | BPF_X: /* dst = dst | src */
+ /* ogr %dst,%src */
+ EMIT4(0xb9810000, dst_reg, src_reg);
break;
- case BPF_RET | BPF_K:
- if (K == 0) {
- jit->seen |= SEEN_RET0;
- if (last)
- break;
- /* j <ret0> */
- EMIT4_PCREL(0xa7f40000, jit->ret0_ip - jit->prg);
- } else {
- if (K <= 16383)
- /* lghi %r2,K */
- EMIT4_IMM(0xa7290000, K);
- else
- /* llgf %r2,<K>(%r13) */
- EMIT6_DISP(0xe320d000, 0x0016, EMIT_CONST(K));
- /* j <exit> */
- if (last && !(jit->seen & SEEN_RET0))
- break;
- EMIT4_PCREL(0xa7f40000, jit->exit_ip - jit->prg);
+ case BPF_ALU | BPF_OR | BPF_K: /* dst = (u32) dst | (u32) imm */
+ /* oilf %dst,imm */
+ EMIT6_IMM(0xc00d0000, dst_reg, imm);
+ EMIT_ZERO(dst_reg);
+ break;
+ case BPF_ALU64 | BPF_OR | BPF_K: /* dst = dst | imm */
+ /* og %dst,<d(imm)>(%l) */
+ EMIT6_DISP_LH(0xe3000000, 0x0081, dst_reg, REG_0, REG_L,
+ EMIT_CONST_U64(imm));
+ break;
+ /*
+ * BPF_XOR
+ */
+ case BPF_ALU | BPF_XOR | BPF_X: /* dst = (u32) dst ^ (u32) src */
+ /* xr %dst,%src */
+ EMIT2(0x1700, dst_reg, src_reg);
+ EMIT_ZERO(dst_reg);
+ break;
+ case BPF_ALU64 | BPF_XOR | BPF_X: /* dst = dst ^ src */
+ /* xgr %dst,%src */
+ EMIT4(0xb9820000, dst_reg, src_reg);
+ break;
+ case BPF_ALU | BPF_XOR | BPF_K: /* dst = (u32) dst ^ (u32) imm */
+ if (!imm)
+ break;
+ /* xilf %dst,imm */
+ EMIT6_IMM(0xc0070000, dst_reg, imm);
+ EMIT_ZERO(dst_reg);
+ break;
+ case BPF_ALU64 | BPF_XOR | BPF_K: /* dst = dst ^ imm */
+ /* xg %dst,<d(imm)>(%l) */
+ EMIT6_DISP_LH(0xe3000000, 0x0082, dst_reg, REG_0, REG_L,
+ EMIT_CONST_U64(imm));
+ break;
+ /*
+ * BPF_LSH
+ */
+ case BPF_ALU | BPF_LSH | BPF_X: /* dst = (u32) dst << (u32) src */
+ /* sll %dst,0(%src) */
+ EMIT4_DISP(0x89000000, dst_reg, src_reg, 0);
+ EMIT_ZERO(dst_reg);
+ break;
+ case BPF_ALU64 | BPF_LSH | BPF_X: /* dst = dst << src */
+ /* sllg %dst,%dst,0(%src) */
+ EMIT6_DISP_LH(0xeb000000, 0x000d, dst_reg, dst_reg, src_reg, 0);
+ break;
+ case BPF_ALU | BPF_LSH | BPF_K: /* dst = (u32) dst << (u32) imm */
+ if (imm == 0)
+ break;
+ /* sll %dst,imm(%r0) */
+ EMIT4_DISP(0x89000000, dst_reg, REG_0, imm);
+ EMIT_ZERO(dst_reg);
+ break;
+ case BPF_ALU64 | BPF_LSH | BPF_K: /* dst = dst << imm */
+ if (imm == 0)
+ break;
+ /* sllg %dst,%dst,imm(%r0) */
+ EMIT6_DISP_LH(0xeb000000, 0x000d, dst_reg, dst_reg, REG_0, imm);
+ break;
+ /*
+ * BPF_RSH
+ */
+ case BPF_ALU | BPF_RSH | BPF_X: /* dst = (u32) dst >> (u32) src */
+ /* srl %dst,0(%src) */
+ EMIT4_DISP(0x88000000, dst_reg, src_reg, 0);
+ EMIT_ZERO(dst_reg);
+ break;
+ case BPF_ALU64 | BPF_RSH | BPF_X: /* dst = dst >> src */
+ /* srlg %dst,%dst,0(%src) */
+ EMIT6_DISP_LH(0xeb000000, 0x000c, dst_reg, dst_reg, src_reg, 0);
+ break;
+ case BPF_ALU | BPF_RSH | BPF_K: /* dst = (u32) dst >> (u32) imm */
+ if (imm == 0)
+ break;
+ /* srl %dst,imm(%r0) */
+ EMIT4_DISP(0x88000000, dst_reg, REG_0, imm);
+ EMIT_ZERO(dst_reg);
+ break;
+ case BPF_ALU64 | BPF_RSH | BPF_K: /* dst = dst >> imm */
+ if (imm == 0)
+ break;
+ /* srlg %dst,%dst,imm(%r0) */
+ EMIT6_DISP_LH(0xeb000000, 0x000c, dst_reg, dst_reg, REG_0, imm);
+ break;
+ /*
+ * BPF_ARSH
+ */
+ case BPF_ALU64 | BPF_ARSH | BPF_X: /* ((s64) dst) >>= src */
+ /* srag %dst,%dst,0(%src) */
+ EMIT6_DISP_LH(0xeb000000, 0x000a, dst_reg, dst_reg, src_reg, 0);
+ break;
+ case BPF_ALU64 | BPF_ARSH | BPF_K: /* ((s64) dst) >>= imm */
+ if (imm == 0)
+ break;
+ /* srag %dst,%dst,imm(%r0) */
+ EMIT6_DISP_LH(0xeb000000, 0x000a, dst_reg, dst_reg, REG_0, imm);
+ break;
+ /*
+ * BPF_NEG
+ */
+ case BPF_ALU | BPF_NEG: /* dst = (u32) -dst */
+ /* lcr %dst,%dst */
+ EMIT2(0x1300, dst_reg, dst_reg);
+ EMIT_ZERO(dst_reg);
+ break;
+ case BPF_ALU64 | BPF_NEG: /* dst = -dst */
+ /* lcgr %dst,%dst */
+ EMIT4(0xb9130000, dst_reg, dst_reg);
+ break;
+ /*
+ * BPF_FROM_BE/LE
+ */
+ case BPF_ALU | BPF_END | BPF_FROM_BE:
+ /* s390 is big endian, therefore only clear high order bytes */
+ switch (imm) {
+ case 16: /* dst = (u16) cpu_to_be16(dst) */
+ /* llghr %dst,%dst */
+ EMIT4(0xb9850000, dst_reg, dst_reg);
+ break;
+ case 32: /* dst = (u32) cpu_to_be32(dst) */
+ /* llgfr %dst,%dst */
+ EMIT4(0xb9160000, dst_reg, dst_reg);
+ break;
+ case 64: /* dst = (u64) cpu_to_be64(dst) */
+ break;
}
break;
- case BPF_RET | BPF_A:
- /* llgfr %r2,%r5 */
- EMIT4(0xb9160025);
+ case BPF_ALU | BPF_END | BPF_FROM_LE:
+ switch (imm) {
+ case 16: /* dst = (u16) cpu_to_le16(dst) */
+ /* lrvr %dst,%dst */
+ EMIT4(0xb91f0000, dst_reg, dst_reg);
+ /* srl %dst,16(%r0) */
+ EMIT4_DISP(0x88000000, dst_reg, REG_0, 16);
+ /* llghr %dst,%dst */
+ EMIT4(0xb9850000, dst_reg, dst_reg);
+ break;
+ case 32: /* dst = (u32) cpu_to_le32(dst) */
+ /* lrvr %dst,%dst */
+ EMIT4(0xb91f0000, dst_reg, dst_reg);
+ /* llgfr %dst,%dst */
+ EMIT4(0xb9160000, dst_reg, dst_reg);
+ break;
+ case 64: /* dst = (u64) cpu_to_le64(dst) */
+ /* lrvgr %dst,%dst */
+ EMIT4(0xb90f0000, dst_reg, dst_reg);
+ break;
+ }
+ break;
+ /*
+ * BPF_ST(X)
+ */
+ case BPF_STX | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = src_reg */
+ /* stcy %src,off(%dst) */
+ EMIT6_DISP_LH(0xe3000000, 0x0072, src_reg, dst_reg, REG_0, off);
+ jit->seen |= SEEN_MEM;
+ break;
+ case BPF_STX | BPF_MEM | BPF_H: /* (u16 *)(dst + off) = src */
+ /* sthy %src,off(%dst) */
+ EMIT6_DISP_LH(0xe3000000, 0x0070, src_reg, dst_reg, REG_0, off);
+ jit->seen |= SEEN_MEM;
+ break;
+ case BPF_STX | BPF_MEM | BPF_W: /* *(u32 *)(dst + off) = src */
+ /* sty %src,off(%dst) */
+ EMIT6_DISP_LH(0xe3000000, 0x0050, src_reg, dst_reg, REG_0, off);
+ jit->seen |= SEEN_MEM;
+ break;
+ case BPF_STX | BPF_MEM | BPF_DW: /* (u64 *)(dst + off) = src */
+ /* stg %src,off(%dst) */
+ EMIT6_DISP_LH(0xe3000000, 0x0024, src_reg, dst_reg, REG_0, off);
+ jit->seen |= SEEN_MEM;
+ break;
+ case BPF_ST | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = imm */
+ /* lhi %w0,imm */
+ EMIT4_IMM(0xa7080000, REG_W0, (u8) imm);
+ /* stcy %w0,off(dst) */
+ EMIT6_DISP_LH(0xe3000000, 0x0072, REG_W0, dst_reg, REG_0, off);
+ jit->seen |= SEEN_MEM;
+ break;
+ case BPF_ST | BPF_MEM | BPF_H: /* (u16 *)(dst + off) = imm */
+ /* lhi %w0,imm */
+ EMIT4_IMM(0xa7080000, REG_W0, (u16) imm);
+ /* sthy %w0,off(dst) */
+ EMIT6_DISP_LH(0xe3000000, 0x0070, REG_W0, dst_reg, REG_0, off);
+ jit->seen |= SEEN_MEM;
+ break;
+ case BPF_ST | BPF_MEM | BPF_W: /* *(u32 *)(dst + off) = imm */
+ /* llilf %w0,imm */
+ EMIT6_IMM(0xc00f0000, REG_W0, (u32) imm);
+ /* sty %w0,off(%dst) */
+ EMIT6_DISP_LH(0xe3000000, 0x0050, REG_W0, dst_reg, REG_0, off);
+ jit->seen |= SEEN_MEM;
+ break;
+ case BPF_ST | BPF_MEM | BPF_DW: /* *(u64 *)(dst + off) = imm */
+ /* lgfi %w0,imm */
+ EMIT6_IMM(0xc0010000, REG_W0, imm);
+ /* stg %w0,off(%dst) */
+ EMIT6_DISP_LH(0xe3000000, 0x0024, REG_W0, dst_reg, REG_0, off);
+ jit->seen |= SEEN_MEM;
+ break;
+ /*
+ * BPF_STX XADD (atomic_add)
+ */
+ case BPF_STX | BPF_XADD | BPF_W: /* *(u32 *)(dst + off) += src */
+ /* laal %w0,%src,off(%dst) */
+ EMIT6_DISP_LH(0xeb000000, 0x00fa, REG_W0, src_reg,
+ dst_reg, off);
+ jit->seen |= SEEN_MEM;
+ break;
+ case BPF_STX | BPF_XADD | BPF_DW: /* *(u64 *)(dst + off) += src */
+ /* laalg %w0,%src,off(%dst) */
+ EMIT6_DISP_LH(0xeb000000, 0x00ea, REG_W0, src_reg,
+ dst_reg, off);
+ jit->seen |= SEEN_MEM;
+ break;
+ /*
+ * BPF_LDX
+ */
+ case BPF_LDX | BPF_MEM | BPF_B: /* dst = *(u8 *)(ul) (src + off) */
+ /* llgc %dst,0(off,%src) */
+ EMIT6_DISP_LH(0xe3000000, 0x0090, dst_reg, src_reg, REG_0, off);
+ jit->seen |= SEEN_MEM;
+ break;
+ case BPF_LDX | BPF_MEM | BPF_H: /* dst = *(u16 *)(ul) (src + off) */
+ /* llgh %dst,0(off,%src) */
+ EMIT6_DISP_LH(0xe3000000, 0x0091, dst_reg, src_reg, REG_0, off);
+ jit->seen |= SEEN_MEM;
+ break;
+ case BPF_LDX | BPF_MEM | BPF_W: /* dst = *(u32 *)(ul) (src + off) */
+ /* llgf %dst,off(%src) */
+ jit->seen |= SEEN_MEM;
+ EMIT6_DISP_LH(0xe3000000, 0x0016, dst_reg, src_reg, REG_0, off);
+ break;
+ case BPF_LDX | BPF_MEM | BPF_DW: /* dst = *(u64 *)(ul) (src + off) */
+ /* lg %dst,0(off,%src) */
+ jit->seen |= SEEN_MEM;
+ EMIT6_DISP_LH(0xe3000000, 0x0004, dst_reg, src_reg, REG_0, off);
+ break;
+ /*
+ * BPF_JMP / CALL
+ */
+ case BPF_JMP | BPF_CALL:
+ {
+ /*
+ * b0 = (__bpf_call_base + imm)(b1, b2, b3, b4, b5)
+ */
+ const u64 func = (u64)__bpf_call_base + imm;
+
+ REG_SET_SEEN(BPF_REG_5);
+ jit->seen |= SEEN_FUNC;
+ /* lg %w1,<d(imm)>(%l) */
+ EMIT6_DISP(0xe3000000, 0x0004, REG_W1, REG_0, REG_L,
+ EMIT_CONST_U64(func));
+ /* basr %r14,%w1 */
+ EMIT2(0x0d00, REG_14, REG_W1);
+ /* lgr %b0,%r2: load return value into %b0 */
+ EMIT4(0xb9040000, BPF_REG_0, REG_2);
+ break;
+ }
+ case BPF_JMP | BPF_EXIT: /* return b0 */
+ last = (i == fp->len - 1) ? 1 : 0;
+ if (last && !(jit->seen & SEEN_RET0))
+ break;
/* j <exit> */
EMIT4_PCREL(0xa7f40000, jit->exit_ip - jit->prg);
break;
- case BPF_ST: /* mem[K] = A */
- jit->seen |= SEEN_MEM;
- /* st %r5,<K>(%r15) */
- EMIT4_DISP(0x5050f000,
- (jit->seen & SEEN_DATAREF) ? 160 + K*4 : K*4);
+ /*
+ * Branch relative (number of skipped instructions) to offset on
+ * condition.
+ *
+ * Condition code to mask mapping:
+ *
+ * CC | Description | Mask
+ * ------------------------------
+ * 0 | Operands equal | 8
+ * 1 | First operand low | 4
+ * 2 | First operand high | 2
+ * 3 | Unused | 1
+ *
+ * For s390x relative branches: ip = ip + off_bytes
+ * For BPF relative branches: insn = insn + off_insns + 1
+ *
+ * For example for s390x with offset 0 we jump to the branch
+ * instruction itself (loop) and for BPF with offset 0 we
+ * branch to the instruction behind the branch.
+ */
+ case BPF_JMP | BPF_JA: /* if (true) */
+ mask = 0xf000; /* j */
+ goto branch_oc;
+ case BPF_JMP | BPF_JSGT | BPF_K: /* ((s64) dst > (s64) imm) */
+ mask = 0x2000; /* jh */
+ goto branch_ks;
+ case BPF_JMP | BPF_JSGE | BPF_K: /* ((s64) dst >= (s64) imm) */
+ mask = 0xa000; /* jhe */
+ goto branch_ks;
+ case BPF_JMP | BPF_JGT | BPF_K: /* (dst_reg > imm) */
+ mask = 0x2000; /* jh */
+ goto branch_ku;
+ case BPF_JMP | BPF_JGE | BPF_K: /* (dst_reg >= imm) */
+ mask = 0xa000; /* jhe */
+ goto branch_ku;
+ case BPF_JMP | BPF_JNE | BPF_K: /* (dst_reg != imm) */
+ mask = 0x7000; /* jne */
+ goto branch_ku;
+ case BPF_JMP | BPF_JEQ | BPF_K: /* (dst_reg == imm) */
+ mask = 0x8000; /* je */
+ goto branch_ku;
+ case BPF_JMP | BPF_JSET | BPF_K: /* (dst_reg & imm) */
+ mask = 0x7000; /* jnz */
+ /* lgfi %w1,imm (load sign extend imm) */
+ EMIT6_IMM(0xc0010000, REG_W1, imm);
+ /* ngr %w1,%dst */
+ EMIT4(0xb9800000, REG_W1, dst_reg);
+ goto branch_oc;
+
+ case BPF_JMP | BPF_JSGT | BPF_X: /* ((s64) dst > (s64) src) */
+ mask = 0x2000; /* jh */
+ goto branch_xs;
+ case BPF_JMP | BPF_JSGE | BPF_X: /* ((s64) dst >= (s64) src) */
+ mask = 0xa000; /* jhe */
+ goto branch_xs;
+ case BPF_JMP | BPF_JGT | BPF_X: /* (dst > src) */
+ mask = 0x2000; /* jh */
+ goto branch_xu;
+ case BPF_JMP | BPF_JGE | BPF_X: /* (dst >= src) */
+ mask = 0xa000; /* jhe */
+ goto branch_xu;
+ case BPF_JMP | BPF_JNE | BPF_X: /* (dst != src) */
+ mask = 0x7000; /* jne */
+ goto branch_xu;
+ case BPF_JMP | BPF_JEQ | BPF_X: /* (dst == src) */
+ mask = 0x8000; /* je */
+ goto branch_xu;
+ case BPF_JMP | BPF_JSET | BPF_X: /* (dst & src) */
+ mask = 0x7000; /* jnz */
+ /* ngrk %w1,%dst,%src */
+ EMIT4_RRF(0xb9e40000, REG_W1, dst_reg, src_reg);
+ goto branch_oc;
+branch_ks:
+ /* lgfi %w1,imm (load sign extend imm) */
+ EMIT6_IMM(0xc0010000, REG_W1, imm);
+ /* cgrj %dst,%w1,mask,off */
+ EMIT6_PCREL(0xec000000, 0x0064, dst_reg, REG_W1, i, off, mask);
break;
- case BPF_STX: /* mem[K] = X : mov %ebx,off8(%rbp) */
- jit->seen |= SEEN_XREG | SEEN_MEM;
- /* st %r12,<K>(%r15) */
- EMIT4_DISP(0x50c0f000,
- (jit->seen & SEEN_DATAREF) ? 160 + K*4 : K*4);
+branch_ku:
+ /* lgfi %w1,imm (load sign extend imm) */
+ EMIT6_IMM(0xc0010000, REG_W1, imm);
+ /* clgrj %dst,%w1,mask,off */
+ EMIT6_PCREL(0xec000000, 0x0065, dst_reg, REG_W1, i, off, mask);
break;
- case BPF_ANC | SKF_AD_PROTOCOL: /* A = ntohs(skb->protocol); */
- BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, protocol) != 2);
- /* lhi %r5,0 */
- EMIT4(0xa7580000);
- /* icm %r5,3,<d(protocol)>(%r2) */
- EMIT4_DISP(0xbf532000, offsetof(struct sk_buff, protocol));
+branch_xs:
+ /* cgrj %dst,%src,mask,off */
+ EMIT6_PCREL(0xec000000, 0x0064, dst_reg, src_reg, i, off, mask);
break;
- case BPF_ANC | SKF_AD_IFINDEX: /* if (!skb->dev) return 0;
- * A = skb->dev->ifindex */
- BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, ifindex) != 4);
- jit->seen |= SEEN_RET0;
- /* lg %r1,<d(dev)>(%r2) */
- EMIT6_DISP(0xe3102000, 0x0004, offsetof(struct sk_buff, dev));
- /* ltgr %r1,%r1 */
- EMIT4(0xb9020011);
- /* jz <ret0> */
- EMIT4_PCREL(0xa7840000, jit->ret0_ip - jit->prg);
- /* l %r5,<d(ifindex)>(%r1) */
- EMIT4_DISP(0x58501000, offsetof(struct net_device, ifindex));
+branch_xu:
+ /* clgrj %dst,%src,mask,off */
+ EMIT6_PCREL(0xec000000, 0x0065, dst_reg, src_reg, i, off, mask);
break;
- case BPF_ANC | SKF_AD_MARK: /* A = skb->mark */
- BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, mark) != 4);
- /* l %r5,<d(mark)>(%r2) */
- EMIT4_DISP(0x58502000, offsetof(struct sk_buff, mark));
+branch_oc:
+ /* brc mask,jmp_off (branch instruction needs 4 bytes) */
+ jmp_off = addrs[i + off + 1] - (addrs[i + 1] - 4);
+ EMIT4_PCREL(0xa7040000 | mask << 8, jmp_off);
break;
- case BPF_ANC | SKF_AD_QUEUE: /* A = skb->queue_mapping */
- BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, queue_mapping) != 2);
- /* lhi %r5,0 */
- EMIT4(0xa7580000);
- /* icm %r5,3,<d(queue_mapping)>(%r2) */
- EMIT4_DISP(0xbf532000, offsetof(struct sk_buff, queue_mapping));
- break;
- case BPF_ANC | SKF_AD_HATYPE: /* if (!skb->dev) return 0;
- * A = skb->dev->type */
- BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, type) != 2);
- jit->seen |= SEEN_RET0;
- /* lg %r1,<d(dev)>(%r2) */
- EMIT6_DISP(0xe3102000, 0x0004, offsetof(struct sk_buff, dev));
- /* ltgr %r1,%r1 */
- EMIT4(0xb9020011);
- /* jz <ret0> */
- EMIT4_PCREL(0xa7840000, jit->ret0_ip - jit->prg);
- /* lhi %r5,0 */
- EMIT4(0xa7580000);
- /* icm %r5,3,<d(type)>(%r1) */
- EMIT4_DISP(0xbf531000, offsetof(struct net_device, type));
- break;
- case BPF_ANC | SKF_AD_RXHASH: /* A = skb->hash */
- BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, hash) != 4);
- /* l %r5,<d(hash)>(%r2) */
- EMIT4_DISP(0x58502000, offsetof(struct sk_buff, hash));
- break;
- case BPF_ANC | SKF_AD_VLAN_TAG:
- case BPF_ANC | SKF_AD_VLAN_TAG_PRESENT:
- BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2);
- BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
- /* lhi %r5,0 */
- EMIT4(0xa7580000);
- /* icm %r5,3,<d(vlan_tci)>(%r2) */
- EMIT4_DISP(0xbf532000, offsetof(struct sk_buff, vlan_tci));
- if (code == (BPF_ANC | SKF_AD_VLAN_TAG)) {
- /* nill %r5,0xefff */
- EMIT4_IMM(0xa5570000, ~VLAN_TAG_PRESENT);
- } else {
- /* nill %r5,0x1000 */
- EMIT4_IMM(0xa5570000, VLAN_TAG_PRESENT);
- /* srl %r5,12 */
- EMIT4_DISP(0x88500000, 12);
- }
- break;
- case BPF_ANC | SKF_AD_PKTTYPE:
- /* lhi %r5,0 */
- EMIT4(0xa7580000);
- /* ic %r5,<d(pkt_type_offset)>(%r2) */
- EMIT4_DISP(0x43502000, PKT_TYPE_OFFSET());
- /* srl %r5,5 */
- EMIT4_DISP(0x88500000, 5);
- break;
- case BPF_ANC | SKF_AD_CPU: /* A = smp_processor_id() */
-#ifdef CONFIG_SMP
- /* l %r5,<d(cpu_nr)> */
- EMIT4_DISP(0x58500000, offsetof(struct _lowcore, cpu_nr));
-#else
- /* lhi %r5,0 */
- EMIT4(0xa7580000);
-#endif
+ /*
+ * BPF_LD
+ */
+ case BPF_LD | BPF_ABS | BPF_B: /* b0 = *(u8 *) (skb->data+imm) */
+ case BPF_LD | BPF_IND | BPF_B: /* b0 = *(u8 *) (skb->data+imm+src) */
+ if ((BPF_MODE(insn->code) == BPF_ABS) && (imm >= 0))
+ func_addr = __pa(sk_load_byte_pos);
+ else
+ func_addr = __pa(sk_load_byte);
+ goto call_fn;
+ case BPF_LD | BPF_ABS | BPF_H: /* b0 = *(u16 *) (skb->data+imm) */
+ case BPF_LD | BPF_IND | BPF_H: /* b0 = *(u16 *) (skb->data+imm+src) */
+ if ((BPF_MODE(insn->code) == BPF_ABS) && (imm >= 0))
+ func_addr = __pa(sk_load_half_pos);
+ else
+ func_addr = __pa(sk_load_half);
+ goto call_fn;
+ case BPF_LD | BPF_ABS | BPF_W: /* b0 = *(u32 *) (skb->data+imm) */
+ case BPF_LD | BPF_IND | BPF_W: /* b0 = *(u32 *) (skb->data+imm+src) */
+ if ((BPF_MODE(insn->code) == BPF_ABS) && (imm >= 0))
+ func_addr = __pa(sk_load_word_pos);
+ else
+ func_addr = __pa(sk_load_word);
+ goto call_fn;
+call_fn:
+ jit->seen |= SEEN_SKB | SEEN_RET0 | SEEN_FUNC;
+ REG_SET_SEEN(REG_14); /* Return address of possible func call */
+
+ /*
+ * Implicit input:
+ * BPF_REG_6 (R7) : skb pointer
+ * REG_SKB_DATA (R12): skb data pointer
+ *
+ * Calculated input:
+ * BPF_REG_2 (R3) : offset of byte(s) to fetch in skb
+ * BPF_REG_5 (R6) : return address
+ *
+ * Output:
+ * BPF_REG_0 (R14): data read from skb
+ *
+ * Scratch registers (BPF_REG_1-5)
+ */
+
+ /* Call function: llilf %w1,func_addr */
+ EMIT6_IMM(0xc00f0000, REG_W1, func_addr);
+
+ /* Offset: lgfi %b2,imm */
+ EMIT6_IMM(0xc0010000, BPF_REG_2, imm);
+ if (BPF_MODE(insn->code) == BPF_IND)
+ /* agfr %b2,%src (%src is s32 here) */
+ EMIT4(0xb9180000, BPF_REG_2, src_reg);
+
+ /* basr %b5,%w1 (%b5 is call saved) */
+ EMIT2(0x0d00, BPF_REG_5, REG_W1);
+
+ /*
+ * Note: For fast access we jump directly after the
+ * jnz instruction from bpf_jit.S
+ */
+ /* jnz <ret0> */
+ EMIT4_PCREL(0xa7740000, jit->ret0_ip - jit->prg);
break;
default: /* too complex, give up */
- goto out;
+ pr_err("Unknown opcode %02x\n", insn->code);
+ return -1;
}
- addrs[i] = jit->prg - jit->start;
- return 0;
-out:
- return -1;
+ return insn_count;
}
+/*
+ * Compile eBPF program into s390x code
+ */
+static int bpf_jit_prog(struct bpf_jit *jit, struct bpf_prog *fp)
+{
+ int i, insn_count;
+
+ jit->lit = jit->lit_start;
+ jit->prg = 0;
+
+ bpf_jit_prologue(jit);
+ for (i = 0; i < fp->len; i += insn_count) {
+ insn_count = bpf_jit_insn(jit, fp, i);
+ if (insn_count < 0)
+ return -1;
+ jit->addrs[i + 1] = jit->prg; /* Next instruction address */
+ }
+ bpf_jit_epilogue(jit);
+
+ jit->lit_start = jit->prg;
+ jit->size = jit->lit;
+ jit->size_prg = jit->prg;
+ return 0;
+}
+
+/*
+ * Classic BPF function stub. BPF programs will be converted into
+ * eBPF and then bpf_int_jit_compile() will be called.
+ */
void bpf_jit_compile(struct bpf_prog *fp)
{
- struct bpf_binary_header *header = NULL;
- unsigned long size, prg_len, lit_len;
- struct bpf_jit jit, cjit;
- unsigned int *addrs;
- int pass, i;
+}
+
+/*
+ * Compile eBPF program "fp"
+ */
+void bpf_int_jit_compile(struct bpf_prog *fp)
+{
+ struct bpf_binary_header *header;
+ struct bpf_jit jit;
+ int pass;
if (!bpf_jit_enable)
return;
- addrs = kcalloc(fp->len, sizeof(*addrs), GFP_KERNEL);
- if (addrs == NULL)
+ memset(&jit, 0, sizeof(jit));
+ jit.addrs = kcalloc(fp->len + 1, sizeof(*jit.addrs), GFP_KERNEL);
+ if (jit.addrs == NULL)
return;
- memset(&jit, 0, sizeof(cjit));
- memset(&cjit, 0, sizeof(cjit));
-
- for (pass = 0; pass < 10; pass++) {
- jit.prg = jit.start;
- jit.lit = jit.mid;
-
- bpf_jit_prologue(&jit);
- bpf_jit_noleaks(&jit, fp->insns);
- for (i = 0; i < fp->len; i++) {
- if (bpf_jit_insn(&jit, fp->insns + i, addrs, i,
- i == fp->len - 1))
- goto out;
- }
- bpf_jit_epilogue(&jit);
- if (jit.start) {
- WARN_ON(jit.prg > cjit.prg || jit.lit > cjit.lit);
- if (memcmp(&jit, &cjit, sizeof(jit)) == 0)
- break;
- } else if (jit.prg == cjit.prg && jit.lit == cjit.lit) {
- prg_len = jit.prg - jit.start;
- lit_len = jit.lit - jit.mid;
- size = prg_len + lit_len;
- if (size >= BPF_SIZE_MAX)
- goto out;
- header = bpf_jit_binary_alloc(size, &jit.start,
- 2, bpf_jit_fill_hole);
- if (!header)
- goto out;
- jit.prg = jit.mid = jit.start + prg_len;
- jit.lit = jit.end = jit.start + prg_len + lit_len;
- jit.base_ip += (unsigned long) jit.start;
- jit.exit_ip += (unsigned long) jit.start;
- jit.ret0_ip += (unsigned long) jit.start;
- }
- cjit = jit;
+ /*
+ * Three initial passes:
+ * - 1/2: Determine clobbered registers
+ * - 3: Calculate program size and addrs arrray
+ */
+ for (pass = 1; pass <= 3; pass++) {
+ if (bpf_jit_prog(&jit, fp))
+ goto free_addrs;
}
+ /*
+ * Final pass: Allocate and generate program
+ */
+ if (jit.size >= BPF_SIZE_MAX)
+ goto free_addrs;
+ header = bpf_jit_binary_alloc(jit.size, &jit.prg_buf, 2, jit_fill_hole);
+ if (!header)
+ goto free_addrs;
+ if (bpf_jit_prog(&jit, fp))
+ goto free_addrs;
if (bpf_jit_enable > 1) {
- bpf_jit_dump(fp->len, jit.end - jit.start, pass, jit.start);
- if (jit.start)
- print_fn_code(jit.start, jit.mid - jit.start);
+ bpf_jit_dump(fp->len, jit.size, pass, jit.prg_buf);
+ if (jit.prg_buf)
+ print_fn_code(jit.prg_buf, jit.size_prg);
}
- if (jit.start) {
+ if (jit.prg_buf) {
set_memory_ro((unsigned long)header, header->pages);
- fp->bpf_func = (void *) jit.start;
+ fp->bpf_func = (void *) jit.prg_buf;
fp->jited = true;
}
-out:
- kfree(addrs);
+free_addrs:
+ kfree(jit.addrs);
}
+/*
+ * Free eBPF program
+ */
void bpf_jit_free(struct bpf_prog *fp)
{
unsigned long addr = (unsigned long)fp->bpf_func & PAGE_MASK;