[S390] zfcpdump support.

[powerpc.git] / arch / s390 / kernel / smp.c

diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 97764f7..7c0143f 100644 (file)
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -31,6 +31,7 @@
 #include <linux/interrupt.h>
 #include <linux/cpu.h>
 #include <linux/timex.h>
+#include <linux/bootmem.h>
 #include <asm/ipl.h>
 #include <asm/setup.h>
 #include <asm/sigp.h>
@@ -40,6 +41,7 @@
 #include <asm/cpcmd.h>
 #include <asm/tlbflush.h>
 #include <asm/timer.h>
+#include <asm/lowcore.h>
 
 extern volatile int __cpu_logical_map[];
 
@@ -395,6 +397,65 @@ void smp_ctl_clear_bit(int cr, int bit)
        on_each_cpu(smp_ctl_bit_callback, &parms, 0, 1);
 }
 
+#if defined(CONFIG_ZFCPDUMP) || defined(CONFIG_ZFCPDUMP_MODULE)
+
+/*
+ * zfcpdump_prefix_array holds prefix registers for the following scenario:
+ * 64 bit zfcpdump kernel and 31 bit kernel which is to be dumped. We have to
+ * save its prefix registers, since they get lost, when switching from 31 bit
+ * to 64 bit.
+ */
+unsigned int zfcpdump_prefix_array[NR_CPUS + 1] \
+       __attribute__((__section__(".data")));
+
+static void __init smp_get_save_areas(void)
+{
+       unsigned int cpu, cpu_num, rc;
+       __u16 boot_cpu_addr;
+
+       if (ipl_info.type != IPL_TYPE_FCP_DUMP)
+               return;
+       boot_cpu_addr = S390_lowcore.cpu_data.cpu_addr;
+       cpu_num = 1;
+       for (cpu = 0; cpu <= 65535; cpu++) {
+               if ((u16) cpu == boot_cpu_addr)
+                       continue;
+               __cpu_logical_map[1] = (__u16) cpu;
+               if (signal_processor(1, sigp_sense) == sigp_not_operational)
+                       continue;
+               if (cpu_num >= NR_CPUS) {
+                       printk("WARNING: Registers for cpu %i are not "
+                              "saved, since dump kernel was compiled with"
+                              "NR_CPUS=%i!\n", cpu_num, NR_CPUS);
+                       continue;
+               }
+               zfcpdump_save_areas[cpu_num] =
+                       alloc_bootmem(sizeof(union save_area));
+               while (1) {
+                       rc = signal_processor(1, sigp_stop_and_store_status);
+                       if (rc != sigp_busy)
+                               break;
+                       cpu_relax();
+               }
+               memcpy(zfcpdump_save_areas[cpu_num],
+                      (void *)(unsigned long) store_prefix() +
+                      SAVE_AREA_BASE, SAVE_AREA_SIZE);
+#ifdef __s390x__
+               /* copy original prefix register */
+               zfcpdump_save_areas[cpu_num]->s390x.pref_reg =
+                       zfcpdump_prefix_array[cpu_num];
+#endif
+               cpu_num++;
+       }
+}
+
+union save_area *zfcpdump_save_areas[NR_CPUS + 1];
+EXPORT_SYMBOL_GPL(zfcpdump_save_areas);
+
+#else
+#define smp_get_save_areas() do { } while (0)
+#endif
+
 /*
  * Lets check how many CPUs we have.
  */
@@ -589,6 +650,7 @@ void __init smp_setup_cpu_possible_map(void)
 {
        unsigned int phy_cpus, pos_cpus, cpu;
 
+       smp_get_save_areas();
        phy_cpus = smp_count_cpus();
        pos_cpus = min(phy_cpus + additional_cpus, (unsigned int) NR_CPUS);