1 files changed, 11 insertions, 116 deletions

diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index 78a19c93b380..b020bea040b7 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -47,23 +47,21 @@ struct bpf_jit {
 
 #define BPF_SIZE_MAX    0xffff  /* Max size for program (16 bit branches) */
 
-#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_TAIL_CALL  32      /* code uses tail calls */
-#define SEEN_REG_AX     64      /* code uses constant blinding */
-#define SEEN_STACK      (SEEN_FUNC | SEEN_MEM | SEEN_SKB)
+#define SEEN_MEM        (1 << 0)        /* use mem[] for temporary storage */
+#define SEEN_RET0       (1 << 1)        /* ret0_ip points to a valid return 0 */
+#define SEEN_LITERAL    (1 << 2)        /* code uses literals */
+#define SEEN_FUNC       (1 << 3)        /* calls C functions */
+#define SEEN_TAIL_CALL  (1 << 4)        /* code uses tail calls */
+#define SEEN_REG_AX     (1 << 5)        /* code uses constant blinding */
+#define SEEN_STACK      (SEEN_FUNC | SEEN_MEM)
 
 /*
  * s390 registers
  */
 #define REG_W0          (MAX_BPF_JIT_REG + 0)   /* Work register 1 (even) */
 #define REG_W1          (MAX_BPF_JIT_REG + 1)   /* Work register 2 (odd) */
-#define REG_SKB_DATA    (MAX_BPF_JIT_REG + 2)   /* SKB data register */
-#define REG_L           (MAX_BPF_JIT_REG + 3)   /* Literal pool register */
-#define REG_15          (MAX_BPF_JIT_REG + 4)   /* Register 15 */
+#define REG_L           (MAX_BPF_JIT_REG + 2)   /* Literal pool register */
+#define REG_15          (MAX_BPF_JIT_REG + 3)   /* Register 15 */
 #define REG_0           REG_W0                  /* Register 0 */
 #define REG_1           REG_W1                  /* Register 1 */
 #define REG_2           BPF_REG_1               /* Register 2 */
@@ -88,10 +86,8 @@ static const int reg2hex[] = {
         [BPF_REG_9]     = 10,
         /* BPF stack pointer */
         [BPF_REG_FP]    = 13,
-        /* Register for blinding (shared with REG_SKB_DATA) */
+        /* Register for blinding */
         [BPF_REG_AX]    = 12,
-        /* SKB data pointer */
-        [REG_SKB_DATA]  = 12,
         /* Work registers for s390x backend */
         [REG_W0]        = 0,
         [REG_W1]        = 1,
@@ -385,27 +381,6 @@ static void save_restore_regs(struct bpf_jit *jit, int op, u32 stack_depth)
 }
 
 /*
- * 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 BPF_REG_AX is not used.
- */
-static void emit_load_skb_data_hlen(struct bpf_jit *jit)
-{
-        /* 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);
-        if (!(jit->seen & SEEN_REG_AX))
-                /* lg %skb_data,data_off(%b1) */
-                EMIT6_DISP_LH(0xe3000000, 0x0004, REG_SKB_DATA, REG_0,
-                              BPF_REG_1, offsetof(struct sk_buff, data));
-}
-
-/*
  * Emit function prologue
  *
  * Save registers and create stack frame if necessary.
@@ -445,12 +420,6 @@ static void bpf_jit_prologue(struct bpf_jit *jit, u32 stack_depth)
                         EMIT6_DISP_LH(0xe3000000, 0x0024, REG_W1, REG_0,
                                       REG_15, 152);
         }
-        if (jit->seen & SEEN_SKB) {
-                emit_load_skb_data_hlen(jit);
-                /* stg %b1,ST_OFF_SKBP(%r0,%r15) */
-                EMIT6_DISP_LH(0xe3000000, 0x0024, BPF_REG_1, REG_0, REG_15,
-                              STK_OFF_SKBP);
-        }
 }
 
 /*
@@ -483,12 +452,12 @@ 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;
+        unsigned int mask;
 
         if (dst_reg == BPF_REG_AX || src_reg == BPF_REG_AX)
                 jit->seen |= SEEN_REG_AX;
@@ -970,13 +939,6 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp, int i
                 EMIT2(0x0d00, REG_14, REG_W1);
                 /* lgr %b0,%r2: load return value into %b0 */
                 EMIT4(0xb9040000, BPF_REG_0, REG_2);
-                if ((jit->seen & SEEN_SKB) &&
-                    bpf_helper_changes_pkt_data((void *)func)) {
-                        /* lg %b1,ST_OFF_SKBP(%r15) */
-                        EMIT6_DISP_LH(0xe3000000, 0x0004, BPF_REG_1, REG_0,
-                                      REG_15, STK_OFF_SKBP);
-                        emit_load_skb_data_hlen(jit);
-                }
                 break;
         }
         case BPF_JMP | BPF_TAIL_CALL:
@@ -1176,73 +1138,6 @@ branch_oc:
                 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 (if no BPF_REG_AX)
-                 *
-                 * 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);
-
-                /* Reload REG_SKB_DATA if BPF_REG_AX is used */
-                if (jit->seen & SEEN_REG_AX)
-                        /* lg %skb_data,data_off(%b6) */
-                        EMIT6_DISP_LH(0xe3000000, 0x0004, REG_SKB_DATA, REG_0,
-                                      BPF_REG_6, offsetof(struct sk_buff, data));
-                /* 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;