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authorJohannes Berg <[email protected]>2024-10-09 08:59:14 +0200
committerJohannes Berg <[email protected]>2024-10-09 08:59:22 +0200
commita0efa2f362a69e47b9d8b48f770ef3a0249a7911 (patch)
tree384d2c79a9b613213ef7591583d820d18c7be9c3 /tools/testing/selftests/bpf/disasm_helpers.c
parentdb03488897a70367aeafe82d07a78943d2a6068e (diff)
parent36efaca9cb28a893cad98f0448c39a8b698859e2 (diff)
Merge net-next/main to resolve conflicts
The wireless-next tree was based on something older, and there are now conflicts between -rc2 and work here. Merge net-next, which has enough of -rc2 for the conflicts to happen, resolving them in the process. Signed-off-by: Johannes Berg <[email protected]>
Diffstat (limited to 'tools/testing/selftests/bpf/disasm_helpers.c')
-rw-r--r--tools/testing/selftests/bpf/disasm_helpers.c69
1 files changed, 69 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/disasm_helpers.c b/tools/testing/selftests/bpf/disasm_helpers.c
new file mode 100644
index 000000000000..f529f1c8c171
--- /dev/null
+++ b/tools/testing/selftests/bpf/disasm_helpers.c
@@ -0,0 +1,69 @@
+// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
+
+#include <bpf/bpf.h>
+#include "disasm.h"
+
+struct print_insn_context {
+ char scratch[16];
+ char *buf;
+ size_t sz;
+};
+
+static void print_insn_cb(void *private_data, const char *fmt, ...)
+{
+ struct print_insn_context *ctx = private_data;
+ va_list args;
+
+ va_start(args, fmt);
+ vsnprintf(ctx->buf, ctx->sz, fmt, args);
+ va_end(args);
+}
+
+static const char *print_call_cb(void *private_data, const struct bpf_insn *insn)
+{
+ struct print_insn_context *ctx = private_data;
+
+ /* For pseudo calls verifier.c:jit_subprogs() hides original
+ * imm to insn->off and changes insn->imm to be an index of
+ * the subprog instead.
+ */
+ if (insn->src_reg == BPF_PSEUDO_CALL) {
+ snprintf(ctx->scratch, sizeof(ctx->scratch), "%+d", insn->off);
+ return ctx->scratch;
+ }
+
+ return NULL;
+}
+
+struct bpf_insn *disasm_insn(struct bpf_insn *insn, char *buf, size_t buf_sz)
+{
+ struct print_insn_context ctx = {
+ .buf = buf,
+ .sz = buf_sz,
+ };
+ struct bpf_insn_cbs cbs = {
+ .cb_print = print_insn_cb,
+ .cb_call = print_call_cb,
+ .private_data = &ctx,
+ };
+ char *tmp, *pfx_end, *sfx_start;
+ bool double_insn;
+ int len;
+
+ print_bpf_insn(&cbs, insn, true);
+ /* We share code with kernel BPF disassembler, it adds '(FF) ' prefix
+ * for each instruction (FF stands for instruction `code` byte).
+ * Remove the prefix inplace, and also simplify call instructions.
+ * E.g.: "(85) call foo#10" -> "call foo".
+ * Also remove newline in the end (the 'max(strlen(buf) - 1, 0)' thing).
+ */
+ pfx_end = buf + 5;
+ sfx_start = buf + max((int)strlen(buf) - 1, 0);
+ if (strncmp(pfx_end, "call ", 5) == 0 && (tmp = strrchr(buf, '#')))
+ sfx_start = tmp;
+ len = sfx_start - pfx_end;
+ memmove(buf, pfx_end, len);
+ buf[len] = 0;
+ double_insn = insn->code == (BPF_LD | BPF_IMM | BPF_DW);
+ return insn + (double_insn ? 2 : 1);
+}