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libbpf: Cleanup the layering between CORE and bpf_program.
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CO-RE processing functions don't need to know 'struct bpf_program' details.
Cleanup the layering to eventually be able to move CO-RE logic into a separate file.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210721000822.40958-2-alexei.starovoitov@gmail.com
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Alexei Starovoitov authored and Andrii Nakryiko committed Jul 26, 2021
1 parent 2b7e9f2 commit 6e43b28
Showing 1 changed file with 38 additions and 36 deletions.
74 changes: 38 additions & 36 deletions tools/lib/bpf/libbpf.c
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Original file line number Diff line number Diff line change
Expand Up @@ -5611,7 +5611,7 @@ static int bpf_core_spec_match(struct bpf_core_spec *local_spec,
return 1;
}

static int bpf_core_calc_field_relo(const struct bpf_program *prog,
static int bpf_core_calc_field_relo(const char *prog_name,
const struct bpf_core_relo *relo,
const struct bpf_core_spec *spec,
__u32 *val, __u32 *field_sz, __u32 *type_id,
Expand Down Expand Up @@ -5655,7 +5655,7 @@ static int bpf_core_calc_field_relo(const struct bpf_program *prog,
*val = sz;
} else {
pr_warn("prog '%s': relo %d at insn #%d can't be applied to array access\n",
prog->name, relo->kind, relo->insn_off / 8);
prog_name, relo->kind, relo->insn_off / 8);
return -EINVAL;
}
if (validate)
Expand All @@ -5677,7 +5677,7 @@ static int bpf_core_calc_field_relo(const struct bpf_program *prog,
if (byte_sz >= 8) {
/* bitfield can't be read with 64-bit read */
pr_warn("prog '%s': relo %d at insn #%d can't be satisfied for bitfield\n",
prog->name, relo->kind, relo->insn_off / 8);
prog_name, relo->kind, relo->insn_off / 8);
return -E2BIG;
}
byte_sz *= 2;
Expand Down Expand Up @@ -5827,7 +5827,7 @@ struct bpf_core_relo_res
* with each other. Otherwise, libbpf will refuse to proceed due to ambiguity.
* If instruction has to be poisoned, *poison will be set to true.
*/
static int bpf_core_calc_relo(const struct bpf_program *prog,
static int bpf_core_calc_relo(const char *prog_name,
const struct bpf_core_relo *relo,
int relo_idx,
const struct bpf_core_spec *local_spec,
Expand All @@ -5845,10 +5845,10 @@ static int bpf_core_calc_relo(const struct bpf_program *prog,
res->orig_type_id = res->new_type_id = 0;

if (core_relo_is_field_based(relo->kind)) {
err = bpf_core_calc_field_relo(prog, relo, local_spec,
err = bpf_core_calc_field_relo(prog_name, relo, local_spec,
&res->orig_val, &res->orig_sz,
&res->orig_type_id, &res->validate);
err = err ?: bpf_core_calc_field_relo(prog, relo, targ_spec,
err = err ?: bpf_core_calc_field_relo(prog_name, relo, targ_spec,
&res->new_val, &res->new_sz,
&res->new_type_id, NULL);
if (err)
Expand Down Expand Up @@ -5906,7 +5906,7 @@ static int bpf_core_calc_relo(const struct bpf_program *prog,
} else if (err == -EOPNOTSUPP) {
/* EOPNOTSUPP means unknown/unsupported relocation */
pr_warn("prog '%s': relo #%d: unrecognized CO-RE relocation %s (%d) at insn #%d\n",
prog->name, relo_idx, core_relo_kind_str(relo->kind),
prog_name, relo_idx, core_relo_kind_str(relo->kind),
relo->kind, relo->insn_off / 8);
}

Expand All @@ -5917,11 +5917,11 @@ static int bpf_core_calc_relo(const struct bpf_program *prog,
* Turn instruction for which CO_RE relocation failed into invalid one with
* distinct signature.
*/
static void bpf_core_poison_insn(struct bpf_program *prog, int relo_idx,
static void bpf_core_poison_insn(const char *prog_name, int relo_idx,
int insn_idx, struct bpf_insn *insn)
{
pr_debug("prog '%s': relo #%d: substituting insn #%d w/ invalid insn\n",
prog->name, relo_idx, insn_idx);
prog_name, relo_idx, insn_idx);
insn->code = BPF_JMP | BPF_CALL;
insn->dst_reg = 0;
insn->src_reg = 0;
Expand Down Expand Up @@ -5977,6 +5977,7 @@ static int bpf_core_patch_insn(struct bpf_program *prog,
int relo_idx,
const struct bpf_core_relo_res *res)
{
const char *prog_name = prog->name;
__u32 orig_val, new_val;
struct bpf_insn *insn;
int insn_idx;
Expand All @@ -5999,8 +6000,8 @@ static int bpf_core_patch_insn(struct bpf_program *prog,
* verifier about "unknown opcode 00"
*/
if (is_ldimm64_insn(insn))
bpf_core_poison_insn(prog, relo_idx, insn_idx + 1, insn + 1);
bpf_core_poison_insn(prog, relo_idx, insn_idx, insn);
bpf_core_poison_insn(prog_name, relo_idx, insn_idx + 1, insn + 1);
bpf_core_poison_insn(prog_name, relo_idx, insn_idx, insn);
return 0;
}

Expand All @@ -6014,61 +6015,61 @@ static int bpf_core_patch_insn(struct bpf_program *prog,
return -EINVAL;
if (res->validate && insn->imm != orig_val) {
pr_warn("prog '%s': relo #%d: unexpected insn #%d (ALU/ALU64) value: got %u, exp %u -> %u\n",
prog->name, relo_idx,
prog_name, relo_idx,
insn_idx, insn->imm, orig_val, new_val);
return -EINVAL;
}
orig_val = insn->imm;
insn->imm = new_val;
pr_debug("prog '%s': relo #%d: patched insn #%d (ALU/ALU64) imm %u -> %u\n",
prog->name, relo_idx, insn_idx,
prog_name, relo_idx, insn_idx,
orig_val, new_val);
break;
case BPF_LDX:
case BPF_ST:
case BPF_STX:
if (res->validate && insn->off != orig_val) {
pr_warn("prog '%s': relo #%d: unexpected insn #%d (LDX/ST/STX) value: got %u, exp %u -> %u\n",
prog->name, relo_idx, insn_idx, insn->off, orig_val, new_val);
prog_name, relo_idx, insn_idx, insn->off, orig_val, new_val);
return -EINVAL;
}
if (new_val > SHRT_MAX) {
pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) value too big: %u\n",
prog->name, relo_idx, insn_idx, new_val);
prog_name, relo_idx, insn_idx, new_val);
return -ERANGE;
}
if (res->fail_memsz_adjust) {
pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) accesses field incorrectly. "
"Make sure you are accessing pointers, unsigned integers, or fields of matching type and size.\n",
prog->name, relo_idx, insn_idx);
prog_name, relo_idx, insn_idx);
goto poison;
}

orig_val = insn->off;
insn->off = new_val;
pr_debug("prog '%s': relo #%d: patched insn #%d (LDX/ST/STX) off %u -> %u\n",
prog->name, relo_idx, insn_idx, orig_val, new_val);
prog_name, relo_idx, insn_idx, orig_val, new_val);

if (res->new_sz != res->orig_sz) {
int insn_bytes_sz, insn_bpf_sz;

insn_bytes_sz = insn_bpf_size_to_bytes(insn);
if (insn_bytes_sz != res->orig_sz) {
pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) unexpected mem size: got %d, exp %u\n",
prog->name, relo_idx, insn_idx, insn_bytes_sz, res->orig_sz);
prog_name, relo_idx, insn_idx, insn_bytes_sz, res->orig_sz);
return -EINVAL;
}

insn_bpf_sz = insn_bytes_to_bpf_size(res->new_sz);
if (insn_bpf_sz < 0) {
pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) invalid new mem size: %u\n",
prog->name, relo_idx, insn_idx, res->new_sz);
prog_name, relo_idx, insn_idx, res->new_sz);
return -EINVAL;
}

insn->code = BPF_MODE(insn->code) | insn_bpf_sz | BPF_CLASS(insn->code);
pr_debug("prog '%s': relo #%d: patched insn #%d (LDX/ST/STX) mem_sz %u -> %u\n",
prog->name, relo_idx, insn_idx, res->orig_sz, res->new_sz);
prog_name, relo_idx, insn_idx, res->orig_sz, res->new_sz);
}
break;
case BPF_LD: {
Expand All @@ -6080,14 +6081,14 @@ static int bpf_core_patch_insn(struct bpf_program *prog,
insn[1].code != 0 || insn[1].dst_reg != 0 ||
insn[1].src_reg != 0 || insn[1].off != 0) {
pr_warn("prog '%s': relo #%d: insn #%d (LDIMM64) has unexpected form\n",
prog->name, relo_idx, insn_idx);
prog_name, relo_idx, insn_idx);
return -EINVAL;
}

imm = insn[0].imm + ((__u64)insn[1].imm << 32);
if (res->validate && imm != orig_val) {
pr_warn("prog '%s': relo #%d: unexpected insn #%d (LDIMM64) value: got %llu, exp %u -> %u\n",
prog->name, relo_idx,
prog_name, relo_idx,
insn_idx, (unsigned long long)imm,
orig_val, new_val);
return -EINVAL;
Expand All @@ -6096,13 +6097,13 @@ static int bpf_core_patch_insn(struct bpf_program *prog,
insn[0].imm = new_val;
insn[1].imm = 0; /* currently only 32-bit values are supported */
pr_debug("prog '%s': relo #%d: patched insn #%d (LDIMM64) imm64 %llu -> %u\n",
prog->name, relo_idx, insn_idx,
prog_name, relo_idx, insn_idx,
(unsigned long long)imm, new_val);
break;
}
default:
pr_warn("prog '%s': relo #%d: trying to relocate unrecognized insn #%d, code:0x%x, src:0x%x, dst:0x%x, off:0x%x, imm:0x%x\n",
prog->name, relo_idx, insn_idx, insn->code,
prog_name, relo_idx, insn_idx, insn->code,
insn->src_reg, insn->dst_reg, insn->off, insn->imm);
return -EINVAL;
}
Expand Down Expand Up @@ -6238,6 +6239,7 @@ static int bpf_core_apply_relo(struct bpf_program *prog,
const struct btf_type *local_type;
const char *local_name;
struct core_cand_list *cands = NULL;
const char *prog_name = prog->name;
__u32 local_id;
const char *spec_str;
int i, j, err;
Expand All @@ -6264,13 +6266,13 @@ static int bpf_core_apply_relo(struct bpf_program *prog,
err = bpf_core_parse_spec(local_btf, local_id, spec_str, relo->kind, &local_spec);
if (err) {
pr_warn("prog '%s': relo #%d: parsing [%d] %s %s + %s failed: %d\n",
prog->name, relo_idx, local_id, btf_kind_str(local_type),
prog_name, relo_idx, local_id, btf_kind_str(local_type),
str_is_empty(local_name) ? "<anon>" : local_name,
spec_str, err);
return -EINVAL;
}

pr_debug("prog '%s': relo #%d: kind <%s> (%d), spec is ", prog->name,
pr_debug("prog '%s': relo #%d: kind <%s> (%d), spec is ", prog_name,
relo_idx, core_relo_kind_str(relo->kind), relo->kind);
bpf_core_dump_spec(LIBBPF_DEBUG, &local_spec);
libbpf_print(LIBBPF_DEBUG, "\n");
Expand All @@ -6287,15 +6289,15 @@ static int bpf_core_apply_relo(struct bpf_program *prog,
/* libbpf doesn't support candidate search for anonymous types */
if (str_is_empty(spec_str)) {
pr_warn("prog '%s': relo #%d: <%s> (%d) relocation doesn't support anonymous types\n",
prog->name, relo_idx, core_relo_kind_str(relo->kind), relo->kind);
prog_name, relo_idx, core_relo_kind_str(relo->kind), relo->kind);
return -EOPNOTSUPP;
}

if (!hashmap__find(cand_cache, type_key, (void **)&cands)) {
cands = bpf_core_find_cands(prog->obj, local_btf, local_id);
if (IS_ERR(cands)) {
pr_warn("prog '%s': relo #%d: target candidate search failed for [%d] %s %s: %ld\n",
prog->name, relo_idx, local_id, btf_kind_str(local_type),
prog_name, relo_idx, local_id, btf_kind_str(local_type),
local_name, PTR_ERR(cands));
return PTR_ERR(cands);
}
Expand All @@ -6311,21 +6313,21 @@ static int bpf_core_apply_relo(struct bpf_program *prog,
cands->cands[i].id, &cand_spec);
if (err < 0) {
pr_warn("prog '%s': relo #%d: error matching candidate #%d ",
prog->name, relo_idx, i);
prog_name, relo_idx, i);
bpf_core_dump_spec(LIBBPF_WARN, &cand_spec);
libbpf_print(LIBBPF_WARN, ": %d\n", err);
return err;
}

pr_debug("prog '%s': relo #%d: %s candidate #%d ", prog->name,
pr_debug("prog '%s': relo #%d: %s candidate #%d ", prog_name,
relo_idx, err == 0 ? "non-matching" : "matching", i);
bpf_core_dump_spec(LIBBPF_DEBUG, &cand_spec);
libbpf_print(LIBBPF_DEBUG, "\n");

if (err == 0)
continue;

err = bpf_core_calc_relo(prog, relo, relo_idx, &local_spec, &cand_spec, &cand_res);
err = bpf_core_calc_relo(prog_name, relo, relo_idx, &local_spec, &cand_spec, &cand_res);
if (err)
return err;

Expand All @@ -6337,7 +6339,7 @@ static int bpf_core_apply_relo(struct bpf_program *prog,
* should all resolve to the same bit offset
*/
pr_warn("prog '%s': relo #%d: field offset ambiguity: %u != %u\n",
prog->name, relo_idx, cand_spec.bit_offset,
prog_name, relo_idx, cand_spec.bit_offset,
targ_spec.bit_offset);
return -EINVAL;
} else if (cand_res.poison != targ_res.poison || cand_res.new_val != targ_res.new_val) {
Expand All @@ -6346,7 +6348,7 @@ static int bpf_core_apply_relo(struct bpf_program *prog,
* proceed due to ambiguity
*/
pr_warn("prog '%s': relo #%d: relocation decision ambiguity: %s %u != %s %u\n",
prog->name, relo_idx,
prog_name, relo_idx,
cand_res.poison ? "failure" : "success", cand_res.new_val,
targ_res.poison ? "failure" : "success", targ_res.new_val);
return -EINVAL;
Expand Down Expand Up @@ -6379,10 +6381,10 @@ static int bpf_core_apply_relo(struct bpf_program *prog,
*/
if (j == 0) {
pr_debug("prog '%s': relo #%d: no matching targets found\n",
prog->name, relo_idx);
prog_name, relo_idx);

/* calculate single target relo result explicitly */
err = bpf_core_calc_relo(prog, relo, relo_idx, &local_spec, NULL, &targ_res);
err = bpf_core_calc_relo(prog_name, relo, relo_idx, &local_spec, NULL, &targ_res);
if (err)
return err;
}
Expand All @@ -6392,7 +6394,7 @@ static int bpf_core_apply_relo(struct bpf_program *prog,
err = bpf_core_patch_insn(prog, relo, relo_idx, &targ_res);
if (err) {
pr_warn("prog '%s': relo #%d: failed to patch insn #%zu: %d\n",
prog->name, relo_idx, relo->insn_off / BPF_INSN_SZ, err);
prog_name, relo_idx, relo->insn_off / BPF_INSN_SZ, err);
return -EINVAL;
}

Expand Down

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