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Diffstat (limited to 'arch/s390/net/bpf_jit_comp.c')
-rw-r--r--arch/s390/net/bpf_jit_comp.c51
1 files changed, 19 insertions, 32 deletions
diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index b15cd2f0320f..78a19c93b380 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -28,8 +28,6 @@
#include <asm/set_memory.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 */
@@ -55,8 +53,7 @@ struct bpf_jit {
#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_SKB_CHANGE 64 /* code changes skb data */
-#define SEEN_REG_AX 128 /* code uses constant blinding */
+#define SEEN_REG_AX 64 /* code uses constant blinding */
#define SEEN_STACK (SEEN_FUNC | SEEN_MEM | SEEN_SKB)
/*
@@ -320,12 +317,12 @@ static void save_regs(struct bpf_jit *jit, u32 rs, u32 re)
/*
* Restore registers from "rs" (register start) to "re" (register end) on stack
*/
-static void restore_regs(struct bpf_jit *jit, u32 rs, u32 re)
+static void restore_regs(struct bpf_jit *jit, u32 rs, u32 re, u32 stack_depth)
{
u32 off = STK_OFF_R6 + (rs - 6) * 8;
if (jit->seen & SEEN_STACK)
- off += STK_OFF;
+ off += STK_OFF + stack_depth;
if (rs == re)
/* lg %rs,off(%r15) */
@@ -369,7 +366,7 @@ static int get_end(struct bpf_jit *jit, int start)
* 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)
+static void save_restore_regs(struct bpf_jit *jit, int op, u32 stack_depth)
{
int re = 6, rs;
@@ -382,7 +379,7 @@ static void save_restore_regs(struct bpf_jit *jit, int op)
if (op == REGS_SAVE)
save_regs(jit, rs, re);
else
- restore_regs(jit, rs, re);
+ restore_regs(jit, rs, re, stack_depth);
re++;
} while (re <= 15);
}
@@ -414,7 +411,7 @@ static void emit_load_skb_data_hlen(struct bpf_jit *jit)
* 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)
+static void bpf_jit_prologue(struct bpf_jit *jit, u32 stack_depth)
{
if (jit->seen & SEEN_TAIL_CALL) {
/* xc STK_OFF_TCCNT(4,%r15),STK_OFF_TCCNT(%r15) */
@@ -427,7 +424,7 @@ static void bpf_jit_prologue(struct bpf_jit *jit)
/* Tail calls have to skip above initialization */
jit->tail_call_start = jit->prg;
/* Save registers */
- save_restore_regs(jit, REGS_SAVE);
+ save_restore_regs(jit, REGS_SAVE, stack_depth);
/* Setup literal pool */
if (jit->seen & SEEN_LITERAL) {
/* basr %r13,0 */
@@ -442,24 +439,24 @@ static void bpf_jit_prologue(struct bpf_jit *jit)
/* 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);
+ EMIT4_IMM(0xa70b0000, REG_15, -(STK_OFF + stack_depth));
if (jit->seen & SEEN_FUNC)
/* stg %w1,152(%r15) (backchain) */
EMIT6_DISP_LH(0xe3000000, 0x0024, REG_W1, REG_0,
REG_15, 152);
}
- if (jit->seen & SEEN_SKB)
+ if (jit->seen & SEEN_SKB) {
emit_load_skb_data_hlen(jit);
- if (jit->seen & SEEN_SKB_CHANGE)
/* stg %b1,ST_OFF_SKBP(%r0,%r15) */
EMIT6_DISP_LH(0xe3000000, 0x0024, BPF_REG_1, REG_0, REG_15,
STK_OFF_SKBP);
+ }
}
/*
* Function epilogue
*/
-static void bpf_jit_epilogue(struct bpf_jit *jit)
+static void bpf_jit_epilogue(struct bpf_jit *jit, u32 stack_depth)
{
/* Return 0 */
if (jit->seen & SEEN_RET0) {
@@ -471,7 +468,7 @@ static void bpf_jit_epilogue(struct bpf_jit *jit)
/* Load exit code: lgr %r2,%b0 */
EMIT4(0xb9040000, REG_2, BPF_REG_0);
/* Restore registers */
- save_restore_regs(jit, REGS_RESTORE);
+ save_restore_regs(jit, REGS_RESTORE, stack_depth);
/* br %r14 */
_EMIT2(0x07fe);
}
@@ -613,11 +610,6 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp, int i
{
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 */
@@ -633,11 +625,6 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp, int i
{
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 */
@@ -983,8 +970,8 @@ 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 (bpf_helper_changes_pkt_data((void *)func)) {
- jit->seen |= SEEN_SKB_CHANGE;
+ 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);
@@ -1019,7 +1006,7 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp, int i
*/
if (jit->seen & SEEN_STACK)
- off = STK_OFF_TCCNT + STK_OFF;
+ off = STK_OFF_TCCNT + STK_OFF + fp->aux->stack_depth;
else
off = STK_OFF_TCCNT;
/* lhi %w0,1 */
@@ -1047,7 +1034,7 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp, int i
/*
* Restore registers before calling function
*/
- save_restore_regs(jit, REGS_RESTORE);
+ save_restore_regs(jit, REGS_RESTORE, fp->aux->stack_depth);
/*
* goto *(prog->bpf_func + tail_call_start);
@@ -1273,7 +1260,7 @@ static int bpf_jit_prog(struct bpf_jit *jit, struct bpf_prog *fp)
jit->lit = jit->lit_start;
jit->prg = 0;
- bpf_jit_prologue(jit);
+ bpf_jit_prologue(jit, fp->aux->stack_depth);
for (i = 0; i < fp->len; i += insn_count) {
insn_count = bpf_jit_insn(jit, fp, i);
if (insn_count < 0)
@@ -1281,7 +1268,7 @@ static int bpf_jit_prog(struct bpf_jit *jit, struct bpf_prog *fp)
/* Next instruction address */
jit->addrs[i + insn_count] = jit->prg;
}
- bpf_jit_epilogue(jit);
+ bpf_jit_epilogue(jit, fp->aux->stack_depth);
jit->lit_start = jit->prg;
jit->size = jit->lit;
@@ -1300,7 +1287,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp)
struct bpf_jit jit;
int pass;
- if (!bpf_jit_enable)
+ if (!fp->jit_requested)
return orig_fp;
tmp = bpf_jit_blind_constants(fp);
generated by cgit (git 2.34.1) at 2024-06-10 19:29:57 +0000