bpf, ppc64: remove ld_abs/ld_ind

Since LD_ABS/LD_IND instructions are now removed from the core and
reimplemented through a combination of inlined BPF instructions and
a slow-path helper, we can get rid of the complexity from ppc64 JIT.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Sandipan Das <sandipan@linux.vnet.ibm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Daniel Borkmann
2018-05-04 01:08:21 +02:00
committed by Alexei Starovoitov
parent 4db25cc988
commit dbf44daf7c
4 changed files with 11 additions and 317 deletions

View File

@@ -20,7 +20,7 @@
* with our redzone usage.
*
* [ prev sp ] <-------------
* [ nv gpr save area ] 8*8 |
* [ nv gpr save area ] 6*8 |
* [ tail_call_cnt ] 8 |
* [ local_tmp_var ] 8 |
* fp (r31) --> [ ebpf stack space ] upto 512 |
@@ -28,8 +28,8 @@
* sp (r1) ---> [ stack pointer ] --------------
*/
/* for gpr non volatile registers BPG_REG_6 to 10, plus skb cache registers */
#define BPF_PPC_STACK_SAVE (8*8)
/* for gpr non volatile registers BPG_REG_6 to 10 */
#define BPF_PPC_STACK_SAVE (6*8)
/* for bpf JIT code internal usage */
#define BPF_PPC_STACK_LOCALS 16
/* stack frame excluding BPF stack, ensure this is quadword aligned */
@@ -39,10 +39,8 @@
#ifndef __ASSEMBLY__
/* BPF register usage */
#define SKB_HLEN_REG (MAX_BPF_JIT_REG + 0)
#define SKB_DATA_REG (MAX_BPF_JIT_REG + 1)
#define TMP_REG_1 (MAX_BPF_JIT_REG + 2)
#define TMP_REG_2 (MAX_BPF_JIT_REG + 3)
#define TMP_REG_1 (MAX_BPF_JIT_REG + 0)
#define TMP_REG_2 (MAX_BPF_JIT_REG + 1)
/* BPF to ppc register mappings */
static const int b2p[] = {
@@ -63,40 +61,23 @@ static const int b2p[] = {
[BPF_REG_FP] = 31,
/* eBPF jit internal registers */
[BPF_REG_AX] = 2,
[SKB_HLEN_REG] = 25,
[SKB_DATA_REG] = 26,
[TMP_REG_1] = 9,
[TMP_REG_2] = 10
};
/* PPC NVR range -- update this if we ever use NVRs below r24 */
#define BPF_PPC_NVR_MIN 24
/* Assembly helpers */
#define DECLARE_LOAD_FUNC(func) u64 func(u64 r3, u64 r4); \
u64 func##_negative_offset(u64 r3, u64 r4); \
u64 func##_positive_offset(u64 r3, u64 r4);
DECLARE_LOAD_FUNC(sk_load_word);
DECLARE_LOAD_FUNC(sk_load_half);
DECLARE_LOAD_FUNC(sk_load_byte);
#define CHOOSE_LOAD_FUNC(imm, func) \
(imm < 0 ? \
(imm >= SKF_LL_OFF ? func##_negative_offset : func) : \
func##_positive_offset)
/* PPC NVR range -- update this if we ever use NVRs below r27 */
#define BPF_PPC_NVR_MIN 27
#define SEEN_FUNC 0x1000 /* might call external helpers */
#define SEEN_STACK 0x2000 /* uses BPF stack */
#define SEEN_SKB 0x4000 /* uses sk_buff */
#define SEEN_TAILCALL 0x8000 /* uses tail calls */
#define SEEN_TAILCALL 0x4000 /* uses tail calls */
struct codegen_context {
/*
* This is used to track register usage as well
* as calls to external helpers.
* - register usage is tracked with corresponding
* bits (r3-r10 and r25-r31)
* bits (r3-r10 and r27-r31)
* - rest of the bits can be used to track other
* things -- for now, we use bits 16 to 23
* encoded in SEEN_* macros above