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-rw-r--r--arch/s390/net/bpf_timed_may_goto.S45
1 files changed, 45 insertions, 0 deletions
diff --git a/arch/s390/net/bpf_timed_may_goto.S b/arch/s390/net/bpf_timed_may_goto.S
new file mode 100644
index 000000000000..06f567a460d7
--- /dev/null
+++ b/arch/s390/net/bpf_timed_may_goto.S
@@ -0,0 +1,45 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#include <linux/export.h>
+#include <linux/linkage.h>
+#include <asm/asm-offsets.h>
+#include <asm/nospec-insn.h>
+
+#define R2_OFF 0
+#define R5_OFF (R2_OFF + (5 - 2 + 1) * 8)
+#define R14_OFF (R5_OFF + 8)
+#define RETADDR_OFF (R14_OFF + 8)
+#define R15_OFF (RETADDR_OFF + 8)
+#define BACKCHAIN_OFF (R15_OFF + 8)
+#define FRAME_SIZE (BACKCHAIN_OFF + 8)
+#define FRAME_OFF (STACK_FRAME_OVERHEAD - FRAME_SIZE)
+#if (FRAME_OFF + BACKCHAIN_OFF) != __SF_BACKCHAIN
+#error Stack frame layout calculation is broken
+#endif
+
+ GEN_BR_THUNK %r1
+
+SYM_FUNC_START(arch_bpf_timed_may_goto)
+ /*
+ * This function has a special ABI: the parameters are in %r12 and
+ * %r13; the return value is in %r12; all GPRs except %r0, %r1, and
+ * %r12 are callee-saved; and the return address is in %r0.
+ */
+ stmg %r2,%r5,FRAME_OFF+R2_OFF(%r15)
+ stg %r14,FRAME_OFF+R14_OFF(%r15)
+ stg %r0,FRAME_OFF+RETADDR_OFF(%r15)
+ stg %r15,FRAME_OFF+R15_OFF(%r15)
+ lgr %r1,%r15
+ lay %r15,-FRAME_SIZE(%r15)
+ stg %r1,__SF_BACKCHAIN(%r15)
+
+ lay %r2,0(%r12,%r13)
+ brasl %r14,bpf_check_timed_may_goto
+ lgr %r12,%r2
+
+ lg %r15,FRAME_SIZE+FRAME_OFF+R15_OFF(%r15)
+ lmg %r2,%r5,FRAME_OFF+R2_OFF(%r15)
+ lg %r14,FRAME_OFF+R14_OFF(%r15)
+ lg %r1,FRAME_OFF+RETADDR_OFF(%r15)
+ BR_EX %r1
+SYM_FUNC_END(arch_bpf_timed_may_goto)