| Message ID | 20230907230550.1417590-5-puranjay12@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 1cfb7eaebeac9270fcb527f47bbdea34ca3cd5b2 |
| Headers | show |
| Series | arm32, bpf: add support for cpuv4 insns | expand |
On Thu, Sep 07, 2023 at 11:05:45PM +0000, Puranjay Mohan wrote: > The cpuv4 added a new unconditional bswap instruction with following > behaviour: > > BPF_ALU64 | BPF_TO_LE | BPF_END with imm = 16/32/64 means: > dst = bswap16(dst) > dst = bswap32(dst) > dst = bswap64(dst) > > As we already support converting to big-endian from little-endian we can > use the same for unconditional bswap. just treat the unconditional scenario > the same as big-endian conversion. > > Signed-off-by: Puranjay Mohan <puranjay12@gmail.com> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Thanks!
diff --git a/arch/arm/net/bpf_jit_32.c b/arch/arm/net/bpf_jit_32.c index 29a1ccf761fd..a08eba850ddf 100644 --- a/arch/arm/net/bpf_jit_32.c +++ b/arch/arm/net/bpf_jit_32.c @@ -1635,10 +1635,12 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) break; /* dst = htole(dst) */ /* dst = htobe(dst) */ - case BPF_ALU | BPF_END | BPF_FROM_LE: - case BPF_ALU | BPF_END | BPF_FROM_BE: + case BPF_ALU | BPF_END | BPF_FROM_LE: /* also BPF_TO_LE */ + case BPF_ALU | BPF_END | BPF_FROM_BE: /* also BPF_TO_BE */ + /* dst = bswap(dst) */ + case BPF_ALU64 | BPF_END | BPF_FROM_LE: /* also BPF_TO_LE */ rd = arm_bpf_get_reg64(dst, tmp, ctx); - if (BPF_SRC(code) == BPF_FROM_LE) + if (BPF_SRC(code) == BPF_FROM_LE && BPF_CLASS(code) != BPF_ALU64) goto emit_bswap_uxt; switch (imm) { case 16:
The cpuv4 added a new unconditional bswap instruction with following behaviour: BPF_ALU64 | BPF_TO_LE | BPF_END with imm = 16/32/64 means: dst = bswap16(dst) dst = bswap32(dst) dst = bswap64(dst) As we already support converting to big-endian from little-endian we can use the same for unconditional bswap. just treat the unconditional scenario the same as big-endian conversion. Signed-off-by: Puranjay Mohan <puranjay12@gmail.com> --- arch/arm/net/bpf_jit_32.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)