(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); \
+ psw_t psw_enter, psw_leave; \
+ 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 */
#include <asm/sclp.h>
typedef void (*relocate_kernel_t)(unsigned long, unsigned long, unsigned long);
+typedef int (*purgatory_t)(int);
extern const unsigned char relocate_kernel[];
extern const unsigned long long relocate_kernel_len;
* Reset the system, copy boot CPU registers to absolute zero,
* and jump to the kdump image
*/
-static void __do_machine_kdump(void *image)
+static void __do_machine_kdump(void *data)
{
- int (*start_kdump)(int);
+ struct kimage *image = data;
+ purgatory_t purgatory;
unsigned long prefix;
+ purgatory = (purgatory_t)image->start;
+
/* store_status() saved the prefix register to lowcore */
prefix = (unsigned long) S390_lowcore.prefixreg_save_area;
memcpy(absolute_pointer(__LC_FPREGS_SAVE_AREA),
phys_to_virt(prefix + __LC_FPREGS_SAVE_AREA), 512);
- __load_psw_mask(PSW_MASK_BASE | PSW_DEFAULT_KEY | PSW_MASK_EA | PSW_MASK_BA);
- start_kdump = (void *)((struct kimage *) image)->start;
- start_kdump(1);
+ call_nodat(1, int, purgatory, int, 1);
- /* Die if start_kdump returns */
+ /* Die if kdump returns */
disabled_wait();
}
static int do_start_kdump(struct kimage *image)
{
- int (*start_kdump)(int) = (void *)image->start;
- int rc;
+ purgatory_t purgatory = (purgatory_t)image->start;
- __arch_local_irq_stnsm(0xfb); /* disable DAT */
- rc = start_kdump(0);
- __arch_local_irq_stosm(0x04); /* enable DAT */
- return rc;
+ return call_nodat(1, int, purgatory, int, 0);
}
#endif /* CONFIG_CRASH_DUMP */
diag308_subcode |= DIAG308_FLAG_EI;
s390_reset_system();
- __arch_local_irq_stnsm(0xfb); /* disable DAT - avoid no-execute */
- (*(relocate_kernel_t)data_mover)(entry, image->start, diag308_subcode);
+ call_nodat(3, void, (relocate_kernel_t)data_mover,
+ unsigned long, entry,
+ unsigned long, image->start,
+ unsigned long, diag308_subcode);
/* Die if kexec returns */
disabled_wait();