diff options
Diffstat (limited to 'arch/s390/net/bpf_jit_comp.c')
-rw-r--r-- | arch/s390/net/bpf_jit_comp.c | 22 |
1 files changed, 19 insertions, 3 deletions
diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c index bb0215d290f4..964a09fd10f1 100644 --- a/arch/s390/net/bpf_jit_comp.c +++ b/arch/s390/net/bpf_jit_comp.c @@ -353,6 +353,15 @@ static bool can_use_rel(struct bpf_jit *jit, int off) } /* + * Return whether given displacement can be encoded using + * Long-Displacement Facility + */ +static bool is_valid_ldisp(int disp) +{ + return disp >= -524288 && disp <= 524287; +} + +/* * Fill whole space with illegal instructions */ static void jit_fill_hole(void *area, unsigned int size) @@ -476,9 +485,16 @@ static void bpf_jit_prologue(struct bpf_jit *jit, u32 stack_depth) save_restore_regs(jit, REGS_SAVE, stack_depth); /* Setup literal pool */ if (is_first_pass(jit) || (jit->seen & SEEN_LITERAL)) { - /* basr %r13,0 */ - EMIT2(0x0d00, REG_L, REG_0); - jit->base_ip = jit->prg; + if (!is_first_pass(jit) && + is_valid_ldisp(jit->size - (jit->prg + 2))) { + /* basr %l,0 */ + EMIT2(0x0d00, REG_L, REG_0); + jit->base_ip = jit->prg; + } else { + /* larl %l,lit32_start */ + EMIT6_PCREL_RILB(0xc0000000, REG_L, jit->lit32_start); + jit->base_ip = jit->lit32_start; + } } /* Setup stack and backchain */ if (is_first_pass(jit) || (jit->seen & SEEN_STACK)) { |