[PATCH] s390: default storage key

Provide an easy way to define a non-zero storage key at compile time.  This is
useful for debugging purposes.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 16 insertions, 5 deletions

diff --git a/arch/s390/kernel/s390_ksyms.c b/arch/s390/kernel/s390_ksyms.c
index 11fd6d556d8f..bee654abb6d3 100644
--- a/arch/s390/kernel/s390_ksyms.c
+++ b/arch/s390/kernel/s390_ksyms.c
@@ -34,7 +34,6 @@ EXPORT_SYMBOL(__clear_user_asm);
 EXPORT_SYMBOL(__strncpy_from_user_asm);
 EXPORT_SYMBOL(__strnlen_user_asm);
 EXPORT_SYMBOL(diag10);
-EXPORT_SYMBOL(default_storage_key);
 
 /*
  * semaphore ops
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index f0679be4f96f..df83215beac3 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -44,6 +44,8 @@
 #include <asm/cpcmd.h>
 #include <asm/lowcore.h>
 #include <asm/irq.h>
+#include <asm/page.h>
+#include <asm/ptrace.h>
 
 /*
  * Machine setup..
@@ -53,7 +55,6 @@ unsigned int console_devno = -1;
 unsigned int console_irq = -1;
 unsigned long memory_size = 0;
 unsigned long machine_flags = 0;
-unsigned int default_storage_key = 0;
 struct {
         unsigned long addr, size, type;
 } memory_chunk[MEMORY_CHUNKS] = { { 0 } };
@@ -402,7 +403,7 @@ setup_lowcore(void)
         lc = (struct _lowcore *)
                 __alloc_bootmem(lc_pages * PAGE_SIZE, lc_pages * PAGE_SIZE, 0);
         memset(lc, 0, lc_pages * PAGE_SIZE);
-        lc->restart_psw.mask = PSW_BASE_BITS;
+        lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
         lc->restart_psw.addr =
                 PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
         lc->external_new_psw.mask = PSW_KERNEL_BITS;
@@ -470,7 +471,7 @@ static void __init
 setup_memory(void)
 {
         unsigned long bootmap_size;
-        unsigned long start_pfn, end_pfn;
+        unsigned long start_pfn, end_pfn, init_pfn;
         unsigned long last_rw_end;
         int i;
 
@@ -481,6 +482,10 @@ setup_memory(void)
         start_pfn = (__pa(&_end) + PAGE_SIZE - 1) >> PAGE_SHIFT;
         end_pfn = max_pfn = memory_end >> PAGE_SHIFT;
 
+        /* Initialize storage key for kernel pages */
+        for (init_pfn = 0 ; init_pfn < start_pfn; init_pfn++)
+                page_set_storage_key(init_pfn << PAGE_SHIFT, PAGE_DEFAULT_KEY);
+
         /*
          * Initialize the boot-time allocator (with low memory only):
          */
@@ -491,7 +496,7 @@ setup_memory(void)
          */
         last_rw_end = start_pfn;
 
-        for (i = 0; i < 16 && memory_chunk[i].size > 0; i++) {
+        for (i = 0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
                 unsigned long start_chunk, end_chunk;
 
                 if (memory_chunk[i].type != CHUNK_READ_WRITE)
@@ -505,6 +510,11 @@ setup_memory(void)
                 if (end_chunk > end_pfn)
                         end_chunk = end_pfn;
                 if (start_chunk < end_chunk) {
+                        /* Initialize storage key for RAM pages */
+                        for (init_pfn = start_chunk ; init_pfn < end_chunk;
+                             init_pfn++)
+                                page_set_storage_key(init_pfn << PAGE_SHIFT,
+                                                     PAGE_DEFAULT_KEY);
                         free_bootmem(start_chunk << PAGE_SHIFT,
                                      (end_chunk - start_chunk) << PAGE_SHIFT);
                         if (last_rw_end < start_chunk)
@@ -513,6 +523,8 @@ setup_memory(void)
                 }
         }
 
+        psw_set_key(PAGE_DEFAULT_KEY);
+
         if (last_rw_end < end_pfn - 1)
                 add_memory_hole(last_rw_end, end_pfn - 1);