s390/mem_detect: introduce z/VM specific diag260 call
In the case when z/VM memory is defined with "define storage config"
command, SCLP storage info is not available. Utilize diag260 "storage
configuration" call, to get information about z/VM specific guest memory
definitions with potential memory holes.
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/boot/mem_detect.c b/arch/s390/boot/mem_detect.c
index 8974e3d..42b0cd2 100644
--- a/arch/s390/boot/mem_detect.c
+++ b/arch/s390/boot/mem_detect.c
@@ -71,6 +71,53 @@ static unsigned long get_mem_detect_end(void)
return 0;
}
+static int __diag260(unsigned long rx1, unsigned long rx2)
+{
+ register unsigned long _rx1 asm("2") = rx1;
+ register unsigned long _rx2 asm("3") = rx2;
+ register unsigned long _ry asm("4") = 0x10; /* storage configuration */
+ int rc = -1; /* fail */
+ unsigned long reg1, reg2;
+ psw_t old = S390_lowcore.program_new_psw;
+
+ asm volatile(
+ " epsw %0,%1\n"
+ " st %0,%[psw_pgm]\n"
+ " st %1,%[psw_pgm]+4\n"
+ " larl %0,1f\n"
+ " stg %0,%[psw_pgm]+8\n"
+ " diag %[rx],%[ry],0x260\n"
+ " ipm %[rc]\n"
+ " srl %[rc],28\n"
+ "1:\n"
+ : "=&d" (reg1), "=&a" (reg2),
+ [psw_pgm] "=Q" (S390_lowcore.program_new_psw),
+ [rc] "+&d" (rc), [ry] "+d" (_ry)
+ : [rx] "d" (_rx1), "d" (_rx2)
+ : "cc", "memory");
+ S390_lowcore.program_new_psw = old;
+ return rc == 0 ? _ry : -1;
+}
+
+static int diag260(void)
+{
+ int rc, i;
+
+ struct {
+ unsigned long start;
+ unsigned long end;
+ } storage_extents[8] __aligned(16); /* VM supports up to 8 extends */
+
+ memset(storage_extents, 0, sizeof(storage_extents));
+ rc = __diag260((unsigned long)storage_extents, sizeof(storage_extents));
+ if (rc == -1)
+ return -1;
+
+ for (i = 0; i < min_t(int, rc, ARRAY_SIZE(storage_extents)); i++)
+ add_mem_detect_block(storage_extents[i].start, storage_extents[i].end + 1);
+ return 0;
+}
+
static int tprot(unsigned long addr)
{
unsigned long pgm_addr;
@@ -132,6 +179,11 @@ void detect_memory(void)
return;
}
+ if (!diag260()) {
+ mem_detect.info_source = MEM_DETECT_DIAG260;
+ return;
+ }
+
scan_memory(rzm);
mem_detect.info_source = MEM_DETECT_TPROT_LOOP;
if (!max_physmem_end)
diff --git a/arch/s390/include/asm/mem_detect.h b/arch/s390/include/asm/mem_detect.h
index 00426c0..6047a28 100644
--- a/arch/s390/include/asm/mem_detect.h
+++ b/arch/s390/include/asm/mem_detect.h
@@ -7,6 +7,7 @@
enum mem_info_source {
MEM_DETECT_NONE = 0,
MEM_DETECT_SCLP_STOR_INFO,
+ MEM_DETECT_DIAG260,
MEM_DETECT_TPROT_LOOP
};