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-rw-r--r--arch/s390/include/asm/stacktrace.h241
1 files changed, 241 insertions, 0 deletions
diff --git a/arch/s390/include/asm/stacktrace.h b/arch/s390/include/asm/stacktrace.h
new file mode 100644
index 0000000000..78f7b729b6
--- /dev/null
+++ b/arch/s390/include/asm/stacktrace.h
@@ -0,0 +1,241 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_S390_STACKTRACE_H
+#define _ASM_S390_STACKTRACE_H
+
+#include <linux/uaccess.h>
+#include <linux/ptrace.h>
+#include <asm/switch_to.h>
+
+enum stack_type {
+ STACK_TYPE_UNKNOWN,
+ STACK_TYPE_TASK,
+ STACK_TYPE_IRQ,
+ STACK_TYPE_NODAT,
+ STACK_TYPE_RESTART,
+ STACK_TYPE_MCCK,
+};
+
+struct stack_info {
+ enum stack_type type;
+ unsigned long begin, end;
+};
+
+const char *stack_type_name(enum stack_type type);
+int get_stack_info(unsigned long sp, struct task_struct *task,
+ struct stack_info *info, unsigned long *visit_mask);
+
+static inline bool on_stack(struct stack_info *info,
+ unsigned long addr, size_t len)
+{
+ if (info->type == STACK_TYPE_UNKNOWN)
+ return false;
+ if (addr + len < addr)
+ return false;
+ return addr >= info->begin && addr + len <= info->end;
+}
+
+/*
+ * Stack layout of a C stack frame.
+ * Kernel uses the packed stack layout (-mpacked-stack).
+ */
+struct stack_frame {
+ union {
+ unsigned long empty[9];
+ struct {
+ unsigned long sie_control_block;
+ unsigned long sie_savearea;
+ unsigned long sie_reason;
+ unsigned long sie_flags;
+ unsigned long sie_control_block_phys;
+ };
+ };
+ unsigned long gprs[10];
+ unsigned long back_chain;
+};
+
+/*
+ * Unlike current_stack_pointer which simply contains the current value of %r15
+ * current_frame_address() returns function stack frame address, which matches
+ * %r15 upon function invocation. It may differ from %r15 later if function
+ * allocates stack for local variables or new stack frame to call other
+ * functions.
+ */
+#define current_frame_address() \
+ ((unsigned long)__builtin_frame_address(0) - \
+ offsetof(struct stack_frame, back_chain))
+
+static __always_inline unsigned long get_stack_pointer(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ if (regs)
+ return (unsigned long)kernel_stack_pointer(regs);
+ if (task == current)
+ return current_frame_address();
+ return (unsigned long)task->thread.ksp;
+}
+
+/*
+ * To keep this simple mark register 2-6 as being changed (volatile)
+ * by the called function, even though register 6 is saved/nonvolatile.
+ */
+#define CALL_FMT_0 "=&d" (r2)
+#define CALL_FMT_1 "+&d" (r2)
+#define CALL_FMT_2 CALL_FMT_1, "+&d" (r3)
+#define CALL_FMT_3 CALL_FMT_2, "+&d" (r4)
+#define CALL_FMT_4 CALL_FMT_3, "+&d" (r5)
+#define CALL_FMT_5 CALL_FMT_4, "+&d" (r6)
+
+#define CALL_CLOBBER_5 "0", "1", "14", "cc", "memory"
+#define CALL_CLOBBER_4 CALL_CLOBBER_5
+#define CALL_CLOBBER_3 CALL_CLOBBER_4, "5"
+#define CALL_CLOBBER_2 CALL_CLOBBER_3, "4"
+#define CALL_CLOBBER_1 CALL_CLOBBER_2, "3"
+#define CALL_CLOBBER_0 CALL_CLOBBER_1
+
+#define CALL_LARGS_0(...) \
+ long dummy = 0
+#define CALL_LARGS_1(t1, a1) \
+ long arg1 = (long)(t1)(a1)
+#define CALL_LARGS_2(t1, a1, t2, a2) \
+ CALL_LARGS_1(t1, a1); \
+ long arg2 = (long)(t2)(a2)
+#define CALL_LARGS_3(t1, a1, t2, a2, t3, a3) \
+ CALL_LARGS_2(t1, a1, t2, a2); \
+ long arg3 = (long)(t3)(a3)
+#define CALL_LARGS_4(t1, a1, t2, a2, t3, a3, t4, a4) \
+ CALL_LARGS_3(t1, a1, t2, a2, t3, a3); \
+ long arg4 = (long)(t4)(a4)
+#define CALL_LARGS_5(t1, a1, t2, a2, t3, a3, t4, a4, t5, a5) \
+ CALL_LARGS_4(t1, a1, t2, a2, t3, a3, t4, a4); \
+ long arg5 = (long)(t5)(a5)
+
+#define CALL_REGS_0 \
+ register long r2 asm("2") = dummy
+#define CALL_REGS_1 \
+ register long r2 asm("2") = arg1
+#define CALL_REGS_2 \
+ CALL_REGS_1; \
+ register long r3 asm("3") = arg2
+#define CALL_REGS_3 \
+ CALL_REGS_2; \
+ register long r4 asm("4") = arg3
+#define CALL_REGS_4 \
+ CALL_REGS_3; \
+ register long r5 asm("5") = arg4
+#define CALL_REGS_5 \
+ CALL_REGS_4; \
+ register long r6 asm("6") = arg5
+
+#define CALL_TYPECHECK_0(...)
+#define CALL_TYPECHECK_1(t, a, ...) \
+ typecheck(t, a)
+#define CALL_TYPECHECK_2(t, a, ...) \
+ CALL_TYPECHECK_1(__VA_ARGS__); \
+ typecheck(t, a)
+#define CALL_TYPECHECK_3(t, a, ...) \
+ CALL_TYPECHECK_2(__VA_ARGS__); \
+ typecheck(t, a)
+#define CALL_TYPECHECK_4(t, a, ...) \
+ CALL_TYPECHECK_3(__VA_ARGS__); \
+ typecheck(t, a)
+#define CALL_TYPECHECK_5(t, a, ...) \
+ CALL_TYPECHECK_4(__VA_ARGS__); \
+ typecheck(t, a)
+
+#define CALL_PARM_0(...) void
+#define CALL_PARM_1(t, a, ...) t
+#define CALL_PARM_2(t, a, ...) t, CALL_PARM_1(__VA_ARGS__)
+#define CALL_PARM_3(t, a, ...) t, CALL_PARM_2(__VA_ARGS__)
+#define CALL_PARM_4(t, a, ...) t, CALL_PARM_3(__VA_ARGS__)
+#define CALL_PARM_5(t, a, ...) t, CALL_PARM_4(__VA_ARGS__)
+#define CALL_PARM_6(t, a, ...) t, CALL_PARM_5(__VA_ARGS__)
+
+/*
+ * Use call_on_stack() to call a function switching to a specified
+ * stack. Proper sign and zero extension of function arguments is
+ * done. Usage:
+ *
+ * rc = call_on_stack(nr, stack, rettype, fn, t1, a1, t2, a2, ...)
+ *
+ * - nr specifies the number of function arguments of fn.
+ * - stack specifies the stack to be used.
+ * - fn is the function to be called.
+ * - rettype is the return type of fn.
+ * - t1, a1, ... are pairs, where t1 must match the type of the first
+ * argument of fn, t2 the second, etc. a1 is the corresponding
+ * first function argument (not name), etc.
+ */
+#define call_on_stack(nr, stack, rettype, fn, ...) \
+({ \
+ rettype (*__fn)(CALL_PARM_##nr(__VA_ARGS__)) = fn; \
+ unsigned long frame = current_frame_address(); \
+ unsigned long __stack = stack; \
+ unsigned long prev; \
+ CALL_LARGS_##nr(__VA_ARGS__); \
+ CALL_REGS_##nr; \
+ \
+ CALL_TYPECHECK_##nr(__VA_ARGS__); \
+ asm volatile( \
+ " lgr %[_prev],15\n" \
+ " lg 15,%[_stack]\n" \
+ " stg %[_frame],%[_bc](15)\n" \
+ " brasl 14,%[_fn]\n" \
+ " lgr 15,%[_prev]\n" \
+ : [_prev] "=&d" (prev), CALL_FMT_##nr \
+ : [_stack] "R" (__stack), \
+ [_bc] "i" (offsetof(struct stack_frame, back_chain)), \
+ [_frame] "d" (frame), \
+ [_fn] "X" (__fn) : CALL_CLOBBER_##nr); \
+ (rettype)r2; \
+})
+
+/*
+ * Use call_nodat() to call a function with DAT disabled.
+ * Proper sign and zero extension of function arguments is done.
+ * Usage:
+ *
+ * rc = call_nodat(nr, rettype, fn, t1, a1, t2, a2, ...)
+ *
+ * - nr specifies the number of function arguments of fn.
+ * - fn is the function to be called, where fn is a physical address.
+ * - rettype is the return type of fn.
+ * - t1, a1, ... are pairs, where t1 must match the type of the first
+ * argument of fn, t2 the second, etc. a1 is the corresponding
+ * first function argument (not name), etc.
+ *
+ * fn() is called with standard C function call ABI, with the exception
+ * that no useful stackframe or stackpointer is passed via register 15.
+ * Therefore the called function must not use r15 to access the stack.
+ */
+#define call_nodat(nr, rettype, fn, ...) \
+({ \
+ rettype (*__fn)(CALL_PARM_##nr(__VA_ARGS__)) = (fn); \
+ /* aligned since psw_leave must not cross page boundary */ \
+ psw_t __aligned(16) psw_leave; \
+ psw_t psw_enter; \
+ CALL_LARGS_##nr(__VA_ARGS__); \
+ CALL_REGS_##nr; \
+ \
+ CALL_TYPECHECK_##nr(__VA_ARGS__); \
+ psw_enter.mask = PSW_KERNEL_BITS & ~PSW_MASK_DAT; \
+ psw_enter.addr = (unsigned long)__fn; \
+ asm volatile( \
+ " epsw 0,1\n" \
+ " risbg 1,0,0,31,32\n" \
+ " larl 7,1f\n" \
+ " stg 1,%[psw_leave]\n" \
+ " stg 7,8+%[psw_leave]\n" \
+ " la 7,%[psw_leave]\n" \
+ " lra 7,0(7)\n" \
+ " larl 1,0f\n" \
+ " lra 14,0(1)\n" \
+ " lpswe %[psw_enter]\n" \
+ "0: lpswe 0(7)\n" \
+ "1:\n" \
+ : CALL_FMT_##nr, [psw_leave] "=Q" (psw_leave) \
+ : [psw_enter] "Q" (psw_enter) \
+ : "7", CALL_CLOBBER_##nr); \
+ (rettype)r2; \
+})
+
+#endif /* _ASM_S390_STACKTRACE_H */