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-rw-r--r--arch/s390/net/Makefile4
-rw-r--r--arch/s390/net/bpf_jit.S115
-rw-r--r--arch/s390/net/bpf_jit.h60
-rw-r--r--arch/s390/net/bpf_jit_comp.c1224
4 files changed, 1403 insertions, 0 deletions
diff --git a/arch/s390/net/Makefile b/arch/s390/net/Makefile
new file mode 100644
index 000000000..90568c33d
--- /dev/null
+++ b/arch/s390/net/Makefile
@@ -0,0 +1,4 @@
+#
+# Arch-specific network modules
+#
+obj-$(CONFIG_BPF_JIT) += bpf_jit.o bpf_jit_comp.o
diff --git a/arch/s390/net/bpf_jit.S b/arch/s390/net/bpf_jit.S
new file mode 100644
index 000000000..a1c917d88
--- /dev/null
+++ b/arch/s390/net/bpf_jit.S
@@ -0,0 +1,115 @@
+/*
+ * BPF Jit compiler for s390, help functions.
+ *
+ * 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 %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 SKF_MAX_NEG_OFF -0x200000 /* SKF_LL_OFF from filter.h */
+
+/*
+ * 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_common(word, 4, llgf) /* r14 = *(u32 *) (skb->data+offset) */
+sk_load_common(half, 2, llgh) /* r14 = *(u16 *) (skb->data+offset) */
+
+/*
+ * Load 1 byte from SKB (optimized version)
+ */
+ /* r14 = *(u8 *) (skb->data+offset) */
+ENTRY(sk_load_byte)
+ 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 %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
+
+#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_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 000000000..de156ba3b
--- /dev/null
+++ b/arch/s390/net/bpf_jit.h
@@ -0,0 +1,60 @@
+/*
+ * 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_SPACE (MAX_BPF_STACK + 8 + 4 + 4 + 160)
+#define STK_160_UNUSED (160 - 11 * 8)
+#define STK_OFF (STK_SPACE - STK_160_UNUSED)
+#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
new file mode 100644
index 000000000..9afb9d602
--- /dev/null
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -0,0 +1,1224 @@
+/*
+ * BPF Jit compiler for s390.
+ *
+ * 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/filter.h>
+#include <linux/init.h>
+#include <asm/cacheflush.h>
+#include <asm/dis.h>
+#include "bpf_jit.h"
+
+int bpf_jit_enable __read_mostly;
+
+struct bpf_jit {
+ 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_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)
+
+/*
+ * 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 */
+
+/*
+ * 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,
+};
+
+static inline u32 reg(u32 dst_reg, u32 src_reg)
+{
+ 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 & 0xffff), 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 */
+ save_restore_regs(jit, REGS_SAVE);
+ /* Setup literal pool */
+ if (jit->seen & SEEN_LITERAL) {
+ /* basr %r13,0 */
+ EMIT2(0x0d00, REG_L, REG_0);
+ jit->base_ip = jit->prg;
+ }
+ /* Setup stack and backchain */
+ if (jit->seen & SEEN_STACK) {
+ if (jit->seen & SEEN_FUNC)
+ /* lgr %w1,%r15 (backchain) */
+ EMIT4(0xb9040000, REG_W1, REG_15);
+ /* la %bfp,STK_160_UNUSED(%r15) (BPF frame pointer) */
+ EMIT4_DISP(0x41000000, BPF_REG_FP, REG_15, STK_160_UNUSED);
+ /* aghi %r15,-STK_OFF */
+ EMIT4_IMM(0xa70b0000, REG_15, -STK_OFF);
+ if (jit->seen & SEEN_FUNC)
+ /* stg %w1,152(%r15) (backchain) */
+ EMIT6_DISP_LH(0xe3000000, 0x0024, REG_W1, 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 %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 */
+ save_restore_regs(jit, REGS_RESTORE);
+ /* br %r14 */
+ _EMIT2(0x07fe);
+}
+
+/*
+ * Compile one eBPF instruction into s390x code
+ *
+ * NOTE: Use noinline because for gcov (-fprofile-arcs) gcc allocates a lot of
+ * stack space for the large switch statement.
+ */
+static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp, int i)
+{
+ 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;
+ 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;
+
+ jit->seen |= SEEN_RET0;
+ /* 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 / src */
+ case BPF_ALU64 | BPF_MOD | BPF_X: /* dst = dst % 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);
+ /* dlgr %w0,%dst */
+ EMIT4(0xb9870000, REG_W0, src_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;
+ }
+ /* 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_ALU64 | BPF_DIV | BPF_K: /* dst = dst / imm */
+ case BPF_ALU64 | BPF_MOD | BPF_K: /* dst = dst % 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(imm));
+ /* lgr %dst,%rc */
+ EMIT4(0xb9040000, dst_reg, rc_reg);
+ break;
+ }
+ /*
+ * 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_ALU64 | BPF_AND | BPF_X: /* dst = dst & src */
+ /* ngr %dst,%src */
+ EMIT4(0xb9800000, dst_reg, src_reg);
+ break;
+ 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_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;
+ /*
+ * 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_ALU64 | BPF_OR | BPF_X: /* dst = dst | src */
+ /* ogr %dst,%src */
+ EMIT4(0xb9810000, dst_reg, src_reg);
+ break;
+ 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_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;
+ /*
+ * 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;
+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;
+branch_xs:
+ /* cgrj %dst,%src,mask,off */
+ EMIT6_PCREL(0xec000000, 0x0064, dst_reg, src_reg, i, off, mask);
+ break;
+branch_xu:
+ /* clgrj %dst,%src,mask,off */
+ EMIT6_PCREL(0xec000000, 0x0065, dst_reg, src_reg, i, off, mask);
+ break;
+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;
+ /*
+ * 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 */
+ pr_err("Unknown opcode %02x\n", insn->code);
+ 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)
+{
+}
+
+/*
+ * 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;
+ memset(&jit, 0, sizeof(jit));
+ jit.addrs = kcalloc(fp->len + 1, sizeof(*jit.addrs), GFP_KERNEL);
+ if (jit.addrs == NULL)
+ return;
+ /*
+ * 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.size, pass, jit.prg_buf);
+ if (jit.prg_buf)
+ print_fn_code(jit.prg_buf, jit.size_prg);
+ }
+ if (jit.prg_buf) {
+ set_memory_ro((unsigned long)header, header->pages);
+ fp->bpf_func = (void *) jit.prg_buf;
+ fp->jited = true;
+ }
+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;
+ struct bpf_binary_header *header = (void *)addr;
+
+ if (!fp->jited)
+ goto free_filter;
+
+ set_memory_rw(addr, header->pages);
+ bpf_jit_binary_free(header);
+
+free_filter:
+ bpf_prog_unlock_free(fp);
+}
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-11-17 14:57:11 +0000