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-rw-r--r--arch/s390/net/bpf_jit_comp.c158
1 files changed, 126 insertions, 32 deletions
diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index 7bddb27c81e3..5ee1ebc6e448 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -189,6 +189,12 @@ static inline void reg_set_seen(struct bpf_jit *jit, u32 b1)
_EMIT4((op) | __pcrel); \
})
+#define EMIT4_PCREL_RIC(op, mask, target) \
+({ \
+ int __rel = ((target) - jit->prg) / 2; \
+ _EMIT4((op) | (mask) << 20 | (__rel & 0xffff)); \
+})
+
#define _EMIT6(op1, op2) \
({ \
if (jit->prg_buf) { \
@@ -250,17 +256,22 @@ static inline void reg_set_seen(struct bpf_jit *jit, u32 b1)
#define EMIT6_PCREL_RILB(op, b, target) \
({ \
- int rel = ((target) - jit->prg) / 2; \
+ unsigned int rel = (int)((target) - jit->prg) / 2; \
_EMIT6((op) | reg_high(b) << 16 | rel >> 16, rel & 0xffff);\
REG_SET_SEEN(b); \
})
#define EMIT6_PCREL_RIL(op, target) \
({ \
- int rel = ((target) - jit->prg) / 2; \
+ unsigned int rel = (int)((target) - jit->prg) / 2; \
_EMIT6((op) | rel >> 16, rel & 0xffff); \
})
+#define EMIT6_PCREL_RILC(op, mask, target) \
+({ \
+ EMIT6_PCREL_RIL((op) | (mask) << 20, (target)); \
+})
+
#define _EMIT6_IMM(op, imm) \
({ \
unsigned int __imm = (imm); \
@@ -323,6 +334,22 @@ static bool is_codegen_pass(struct bpf_jit *jit)
}
/*
+ * Return whether "rel" can be encoded as a short PC-relative offset
+ */
+static bool is_valid_rel(int rel)
+{
+ return rel >= -65536 && rel <= 65534;
+}
+
+/*
+ * Return whether "off" can be reached using a short PC-relative offset
+ */
+static bool can_use_rel(struct bpf_jit *jit, int off)
+{
+ return is_valid_rel(off - jit->prg);
+}
+
+/*
* Fill whole space with illegal instructions
*/
static void jit_fill_hole(void *area, unsigned int size)
@@ -525,9 +552,9 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp,
int i, bool extra_pass)
{
struct bpf_insn *insn = &fp->insnsi[i];
- int jmp_off, last, insn_count = 1;
u32 dst_reg = insn->dst_reg;
u32 src_reg = insn->src_reg;
+ int last, insn_count = 1;
u32 *addrs = jit->addrs;
s32 imm = insn->imm;
s16 off = insn->off;
@@ -1071,9 +1098,17 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp,
/* llgf %w1,map.max_entries(%b2) */
EMIT6_DISP_LH(0xe3000000, 0x0016, REG_W1, REG_0, BPF_REG_2,
offsetof(struct bpf_array, map.max_entries));
- /* clrj %b3,%w1,0xa,label0: if (u32)%b3 >= (u32)%w1 goto out */
- EMIT6_PCREL_LABEL(0xec000000, 0x0077, BPF_REG_3,
- REG_W1, 0, 0xa);
+ /* if ((u32)%b3 >= (u32)%w1) goto out; */
+ if (!is_first_pass(jit) && can_use_rel(jit, jit->labels[0])) {
+ /* clrj %b3,%w1,0xa,label0 */
+ EMIT6_PCREL_LABEL(0xec000000, 0x0077, BPF_REG_3,
+ REG_W1, 0, 0xa);
+ } else {
+ /* clr %b3,%w1 */
+ EMIT2(0x1500, BPF_REG_3, REG_W1);
+ /* brcl 0xa,label0 */
+ EMIT6_PCREL_RILC(0xc0040000, 0xa, jit->labels[0]);
+ }
/*
* if (tail_call_cnt++ > MAX_TAIL_CALL_CNT)
@@ -1088,9 +1123,16 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp,
EMIT4_IMM(0xa7080000, REG_W0, 1);
/* laal %w1,%w0,off(%r15) */
EMIT6_DISP_LH(0xeb000000, 0x00fa, REG_W1, REG_W0, REG_15, off);
- /* clij %w1,MAX_TAIL_CALL_CNT,0x2,label0 */
- EMIT6_PCREL_IMM_LABEL(0xec000000, 0x007f, REG_W1,
- MAX_TAIL_CALL_CNT, 0, 0x2);
+ if (!is_first_pass(jit) && can_use_rel(jit, jit->labels[0])) {
+ /* clij %w1,MAX_TAIL_CALL_CNT,0x2,label0 */
+ EMIT6_PCREL_IMM_LABEL(0xec000000, 0x007f, REG_W1,
+ MAX_TAIL_CALL_CNT, 0, 0x2);
+ } else {
+ /* clfi %w1,MAX_TAIL_CALL_CNT */
+ EMIT6_IMM(0xc20f0000, REG_W1, MAX_TAIL_CALL_CNT);
+ /* brcl 0x2,label0 */
+ EMIT6_PCREL_RILC(0xc0040000, 0x2, jit->labels[0]);
+ }
/*
* prog = array->ptrs[index];
@@ -1102,11 +1144,16 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp,
EMIT4(0xb9160000, REG_1, BPF_REG_3);
/* sllg %r1,%r1,3: %r1 *= 8 */
EMIT6_DISP_LH(0xeb000000, 0x000d, REG_1, REG_1, REG_0, 3);
- /* lg %r1,prog(%b2,%r1) */
- EMIT6_DISP_LH(0xe3000000, 0x0004, REG_1, BPF_REG_2,
+ /* ltg %r1,prog(%b2,%r1) */
+ EMIT6_DISP_LH(0xe3000000, 0x0002, REG_1, BPF_REG_2,
REG_1, offsetof(struct bpf_array, ptrs));
- /* clgij %r1,0,0x8,label0 */
- EMIT6_PCREL_IMM_LABEL(0xec000000, 0x007d, REG_1, 0, 0, 0x8);
+ if (!is_first_pass(jit) && can_use_rel(jit, jit->labels[0])) {
+ /* brc 0x8,label0 */
+ EMIT4_PCREL_RIC(0xa7040000, 0x8, jit->labels[0]);
+ } else {
+ /* brcl 0x8,label0 */
+ EMIT6_PCREL_RILC(0xc0040000, 0x8, jit->labels[0]);
+ }
/*
* Restore registers before calling function
@@ -1263,36 +1310,83 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp,
goto branch_oc;
branch_ks:
is_jmp32 = BPF_CLASS(insn->code) == BPF_JMP32;
- /* lgfi %w1,imm (load sign extend imm) */
- EMIT6_IMM(0xc0010000, REG_W1, imm);
- /* crj or cgrj %dst,%w1,mask,off */
- EMIT6_PCREL(0xec000000, (is_jmp32 ? 0x0076 : 0x0064),
- dst_reg, REG_W1, i, off, mask);
+ /* cfi or cgfi %dst,imm */
+ EMIT6_IMM(is_jmp32 ? 0xc20d0000 : 0xc20c0000,
+ dst_reg, imm);
+ if (!is_first_pass(jit) &&
+ can_use_rel(jit, addrs[i + off + 1])) {
+ /* brc mask,off */
+ EMIT4_PCREL_RIC(0xa7040000,
+ mask >> 12, addrs[i + off + 1]);
+ } else {
+ /* brcl mask,off */
+ EMIT6_PCREL_RILC(0xc0040000,
+ mask >> 12, addrs[i + off + 1]);
+ }
break;
branch_ku:
is_jmp32 = BPF_CLASS(insn->code) == BPF_JMP32;
- /* lgfi %w1,imm (load sign extend imm) */
- EMIT6_IMM(0xc0010000, REG_W1, imm);
- /* clrj or clgrj %dst,%w1,mask,off */
- EMIT6_PCREL(0xec000000, (is_jmp32 ? 0x0077 : 0x0065),
- dst_reg, REG_W1, i, off, mask);
+ /* clfi or clgfi %dst,imm */
+ EMIT6_IMM(is_jmp32 ? 0xc20f0000 : 0xc20e0000,
+ dst_reg, imm);
+ if (!is_first_pass(jit) &&
+ can_use_rel(jit, addrs[i + off + 1])) {
+ /* brc mask,off */
+ EMIT4_PCREL_RIC(0xa7040000,
+ mask >> 12, addrs[i + off + 1]);
+ } else {
+ /* brcl mask,off */
+ EMIT6_PCREL_RILC(0xc0040000,
+ mask >> 12, addrs[i + off + 1]);
+ }
break;
branch_xs:
is_jmp32 = BPF_CLASS(insn->code) == BPF_JMP32;
- /* crj or cgrj %dst,%src,mask,off */
- EMIT6_PCREL(0xec000000, (is_jmp32 ? 0x0076 : 0x0064),
- dst_reg, src_reg, i, off, mask);
+ if (!is_first_pass(jit) &&
+ can_use_rel(jit, addrs[i + off + 1])) {
+ /* crj or cgrj %dst,%src,mask,off */
+ EMIT6_PCREL(0xec000000, (is_jmp32 ? 0x0076 : 0x0064),
+ dst_reg, src_reg, i, off, mask);
+ } else {
+ /* cr or cgr %dst,%src */
+ if (is_jmp32)
+ EMIT2(0x1900, dst_reg, src_reg);
+ else
+ EMIT4(0xb9200000, dst_reg, src_reg);
+ /* brcl mask,off */
+ EMIT6_PCREL_RILC(0xc0040000,
+ mask >> 12, addrs[i + off + 1]);
+ }
break;
branch_xu:
is_jmp32 = BPF_CLASS(insn->code) == BPF_JMP32;
- /* clrj or clgrj %dst,%src,mask,off */
- EMIT6_PCREL(0xec000000, (is_jmp32 ? 0x0077 : 0x0065),
- dst_reg, src_reg, i, off, mask);
+ if (!is_first_pass(jit) &&
+ can_use_rel(jit, addrs[i + off + 1])) {
+ /* clrj or clgrj %dst,%src,mask,off */
+ EMIT6_PCREL(0xec000000, (is_jmp32 ? 0x0077 : 0x0065),
+ dst_reg, src_reg, i, off, mask);
+ } else {
+ /* clr or clgr %dst,%src */
+ if (is_jmp32)
+ EMIT2(0x1500, dst_reg, src_reg);
+ else
+ EMIT4(0xb9210000, dst_reg, src_reg);
+ /* brcl mask,off */
+ EMIT6_PCREL_RILC(0xc0040000,
+ mask >> 12, addrs[i + off + 1]);
+ }
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);
+ if (!is_first_pass(jit) &&
+ can_use_rel(jit, addrs[i + off + 1])) {
+ /* brc mask,off */
+ EMIT4_PCREL_RIC(0xa7040000,
+ mask >> 12, addrs[i + off + 1]);
+ } else {
+ /* brcl mask,off */
+ EMIT6_PCREL_RILC(0xc0040000,
+ mask >> 12, addrs[i + off + 1]);
+ }
break;
}
default: /* too complex, give up */
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-12-05 00:34:58 +0000