1 files changed, 59 insertions, 41 deletions

diff --git a/arch/s390/mm/extmem.c b/arch/s390/mm/extmem.c
index fd0dae9d10f4..f7da53e212f5 100644
--- a/arch/s390/mm/extmem.c
+++ b/arch/s390/mm/extmem.c
@@ -20,14 +20,16 @@
 #include <linux/ctype.h>
 #include <linux/ioport.h>
 #include <linux/refcount.h>
+#include <linux/pgtable.h>
+#include <asm/machine.h>
 #include <asm/diag.h>
 #include <asm/page.h>
-#include <asm/pgtable.h>
 #include <asm/ebcdic.h>
 #include <asm/errno.h>
 #include <asm/extmem.h>
 #include <asm/cpcmd.h>
 #include <asm/setup.h>
+#include <asm/asm.h>
 
 #define DCSS_PURGESEG   0x08
 #define DCSS_LOADSHRX	0x20
@@ -134,20 +136,21 @@ dcss_diag(int *func, void *parameter,
            unsigned long *ret1, unsigned long *ret2)
 {
 	unsigned long rx, ry;
-	int rc;
+	int cc;
 
-	rx = (unsigned long) parameter;
+	rx = virt_to_phys(parameter);
 	ry = (unsigned long) *func;
 
 	diag_stat_inc(DIAG_STAT_X064);
 	asm volatile(
-		"	diag	%0,%1,0x64\n"
-		"	ipm	%2\n"
-		"	srl	%2,28\n"
-		: "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
+		"	diag	%[rx],%[ry],0x64\n"
+		CC_IPM(cc)
+		: CC_OUT(cc, cc), [rx] "+d" (rx), [ry] "+d" (ry)
+		:
+		: CC_CLOBBER);
 	*ret1 = rx;
 	*ret2 = ry;
-	return rc;
+	return CC_TRANSFORM(cc);
 }
 
 static inline int
@@ -178,7 +181,7 @@ query_segment_type (struct dcss_segment *seg)
 
 	/* initialize diag input parameters */
 	qin->qopcode = DCSS_FINDSEGA;
-	qin->qoutptr = (unsigned long) qout;
+	qin->qoutptr = virt_to_phys(qout);
 	qin->qoutlen = sizeof(struct qout64);
 	memcpy (qin->qname, seg->dcss_name, 8);
 
@@ -253,7 +256,7 @@ segment_type (char* name)
 	int rc;
 	struct dcss_segment seg;
 
-	if (!MACHINE_IS_VM)
+	if (!machine_is_vm())
 		return -ENOSYS;
 
 	dcss_mkname(name, seg.dcss_name);
@@ -289,15 +292,17 @@ segment_overlaps_others (struct dcss_segment *seg)
 
 /*
  * real segment loading function, called from segment_load
+ * Must return either an error code < 0, or the segment type code >= 0
  */
 static int
 __segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long *end)
 {
 	unsigned long start_addr, end_addr, dummy;
 	struct dcss_segment *seg;
-	int rc, diag_cc;
+	int rc, diag_cc, segtype;
 
 	start_addr = end_addr = 0;
+	segtype = -1;
 	seg = kmalloc(sizeof(*seg), GFP_KERNEL | GFP_DMA);
 	if (seg == NULL) {
 		rc = -ENOMEM;
@@ -313,15 +318,10 @@ __segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long
 		goto out_free;
 	}
 
-	rc = vmem_add_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
-
-	if (rc)
-		goto out_free;
-
 	seg->res = kzalloc(sizeof(struct resource), GFP_KERNEL);
 	if (seg->res == NULL) {
 		rc = -ENOMEM;
-		goto out_shared;
+		goto out_free;
 	}
 	seg->res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
 	seg->res->start = seg->start_addr;
@@ -331,16 +331,21 @@ __segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long
 	seg->res_name[8] = '\0';
 	strlcat(seg->res_name, " (DCSS)", sizeof(seg->res_name));
 	seg->res->name = seg->res_name;
-	rc = seg->vm_segtype;
-	if (rc == SEG_TYPE_SC ||
-	    ((rc == SEG_TYPE_SR || rc == SEG_TYPE_ER) && !do_nonshared))
+	segtype = seg->vm_segtype;
+	if (segtype == SEG_TYPE_SC ||
+	    ((segtype == SEG_TYPE_SR || segtype == SEG_TYPE_ER) && !do_nonshared))
 		seg->res->flags |= IORESOURCE_READONLY;
+
+	/* Check for overlapping resources before adding the mapping. */
 	if (request_resource(&iomem_resource, seg->res)) {
 		rc = -EBUSY;
-		kfree(seg->res);
-		goto out_shared;
+		goto out_free_resource;
 	}
 
+	rc = vmem_add_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
+	if (rc)
+		goto out_resource;
+
 	if (do_nonshared)
 		diag_cc = dcss_diag(&loadnsr_scode, seg->dcss_name,
 				&start_addr, &end_addr);
@@ -351,14 +356,14 @@ __segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long
 		dcss_diag(&purgeseg_scode, seg->dcss_name,
 				&dummy, &dummy);
 		rc = diag_cc;
-		goto out_resource;
+		goto out_mapping;
 	}
 	if (diag_cc > 1) {
 		pr_warn("Loading DCSS %s failed with rc=%ld\n", name, end_addr);
 		rc = dcss_diag_translate_rc(end_addr);
 		dcss_diag(&purgeseg_scode, seg->dcss_name,
 				&dummy, &dummy);
-		goto out_resource;
+		goto out_mapping;
 	}
 	seg->start_addr = start_addr;
 	seg->end = end_addr;
@@ -377,15 +382,16 @@ __segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long
 			(void*) seg->end, segtype_string[seg->vm_segtype]);
 	}
 	goto out;
+ out_mapping:
+	vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
  out_resource:
 	release_resource(seg->res);
+ out_free_resource:
 	kfree(seg->res);
- out_shared:
-	vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
  out_free:
 	kfree(seg);
  out:
-	return rc;
+	return rc < 0 ? rc : segtype;
 }
 
 /*
@@ -400,8 +406,7 @@ __segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long
  * -EIO     : could not perform query or load diagnose
  * -ENOENT  : no such segment
  * -EOPNOTSUPP: multi-part segment cannot be used with linux
- * -ENOSPC  : segment cannot be used (overlaps with storage)
- * -EBUSY   : segment can temporarily not be used (overlaps with dcss)
+ * -EBUSY   : segment cannot be used (overlaps with dcss or storage)
  * -ERANGE  : segment cannot be used (exceeds kernel mapping range)
  * -EPERM   : segment is currently loaded with incompatible permissions
  * -ENOMEM  : out of memory
@@ -414,7 +419,7 @@ segment_load (char *name, int do_nonshared, unsigned long *addr,
 	struct dcss_segment *seg;
 	int rc;
 
-	if (!MACHINE_IS_VM)
+	if (!machine_is_vm())
 		return -ENOSYS;
 
 	mutex_lock(&dcss_lock);
@@ -525,6 +530,14 @@ segment_modify_shared (char *name, int do_nonshared)
 	return rc;
 }
 
+static void __dcss_diag_purge_on_cpu_0(void *data)
+{
+	struct dcss_segment *seg = (struct dcss_segment *)data;
+	unsigned long dummy;
+
+	dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
+}
+
 /*
  * Decrease the use count of a DCSS segment and remove
  * it from the address space if nobody is using it
@@ -533,10 +546,9 @@ segment_modify_shared (char *name, int do_nonshared)
 void
 segment_unload(char *name)
 {
-	unsigned long dummy;
 	struct dcss_segment *seg;
 
-	if (!MACHINE_IS_VM)
+	if (!machine_is_vm())
 		return;
 
 	mutex_lock(&dcss_lock);
@@ -551,7 +563,14 @@ segment_unload(char *name)
 	kfree(seg->res);
 	vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
 	list_del(&seg->list);
-	dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
+	/*
+	 * Workaround for z/VM issue, where calling the DCSS unload diag on
+	 * a non-IPL CPU would cause bogus sclp maximum memory detection on
+	 * next IPL.
+	 * IPL CPU 0 cannot be set offline, so the dcss_diag() call can
+	 * directly be scheduled to that CPU.
+	 */
+	smp_call_function_single(0, __dcss_diag_purge_on_cpu_0, seg, 1);
 	kfree(seg);
 out_unlock:
 	mutex_unlock(&dcss_lock);
@@ -568,7 +587,7 @@ segment_save(char *name)
 	char cmd2[80];
 	int i, response;
 
-	if (!MACHINE_IS_VM)
+	if (!machine_is_vm())
 		return;
 
 	mutex_lock(&dcss_lock);
@@ -626,10 +645,6 @@ void segment_warning(int rc, char *seg_name)
 		pr_err("DCSS %s has multiple page ranges and cannot be "
 		       "loaded or queried\n", seg_name);
 		break;
-	case -ENOSPC:
-		pr_err("DCSS %s overlaps with used storage and cannot "
-		       "be loaded\n", seg_name);
-		break;
 	case -EBUSY:
 		pr_err("%s needs used memory resources and cannot be "
 		       "loaded or queried\n", seg_name);
@@ -642,10 +657,13 @@ void segment_warning(int rc, char *seg_name)
 		pr_err("There is not enough memory to load or query "
 		       "DCSS %s\n", seg_name);
 		break;
-	case -ERANGE:
-		pr_err("DCSS %s exceeds the kernel mapping range (%lu) "
-		       "and cannot be loaded\n", seg_name, VMEM_MAX_PHYS);
+	case -ERANGE: {
+		struct range mhp_range = arch_get_mappable_range();
+
+		pr_err("DCSS %s exceeds the kernel mapping range (%llu) "
+		       "and cannot be loaded\n", seg_name, mhp_range.end + 1);
 		break;
+	}
 	default:
 		break;
 	}