1 files changed, 328 insertions, 0 deletions
diff --git a/arch/s390/boot/physmem_info.c b/arch/s390/boot/physmem_info.c
new file mode 100644
index 000000000..0cf79826e
--- /dev/null
+++ b/arch/s390/boot/physmem_info.c
@@ -0,0 +1,328 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/processor.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <asm/physmem_info.h>
+#include <asm/stacktrace.h>
+#include <asm/boot_data.h>
+#include <asm/sparsemem.h>
+#include <asm/sections.h>
+#include <asm/setup.h>
+#include <asm/sclp.h>
+#include <asm/uv.h>
+#include "decompressor.h"
+#include "boot.h"
+
+struct physmem_info __bootdata(physmem_info);
+static unsigned int physmem_alloc_ranges;
+static unsigned long physmem_alloc_pos;
+
+/* up to 256 storage elements, 1020 subincrements each */
+#define ENTRIES_EXTENDED_MAX						       \
+	(256 * (1020 / 2) * sizeof(struct physmem_range))
+
+static struct physmem_range *__get_physmem_range_ptr(u32 n)
+{
+	if (n < MEM_INLINED_ENTRIES)
+		return &physmem_info.online[n];
+	if (unlikely(!physmem_info.online_extended)) {
+		physmem_info.online_extended = (struct physmem_range *)physmem_alloc_range(
+			RR_MEM_DETECT_EXTENDED, ENTRIES_EXTENDED_MAX, sizeof(long), 0,
+			physmem_alloc_pos, true);
+	}
+	return &physmem_info.online_extended[n - MEM_INLINED_ENTRIES];
+}
+
+/*
+ * sequential calls to add_physmem_online_range with adjacent memory ranges
+ * are merged together into single memory range.
+ */
+void add_physmem_online_range(u64 start, u64 end)
+{
+	struct physmem_range *range;
+
+	if (physmem_info.range_count) {
+		range = __get_physmem_range_ptr(physmem_info.range_count - 1);
+		if (range->end == start) {
+			range->end = end;
+			return;
+		}
+	}
+
+	range = __get_physmem_range_ptr(physmem_info.range_count);
+	range->start = start;
+	range->end = end;
+	physmem_info.range_count++;
+}
+
+static int __diag260(unsigned long rx1, unsigned long rx2)
+{
+	unsigned long reg1, reg2, ry;
+	union register_pair rx;
+	psw_t old;
+	int rc;
+
+	rx.even = rx1;
+	rx.odd	= rx2;
+	ry = 0x10; /* storage configuration */
+	rc = -1;   /* fail */
+	asm volatile(
+		"	mvc	0(16,%[psw_old]),0(%[psw_pgm])\n"
+		"	epsw	%[reg1],%[reg2]\n"
+		"	st	%[reg1],0(%[psw_pgm])\n"
+		"	st	%[reg2],4(%[psw_pgm])\n"
+		"	larl	%[reg1],1f\n"
+		"	stg	%[reg1],8(%[psw_pgm])\n"
+		"	diag	%[rx],%[ry],0x260\n"
+		"	ipm	%[rc]\n"
+		"	srl	%[rc],28\n"
+		"1:	mvc	0(16,%[psw_pgm]),0(%[psw_old])\n"
+		: [reg1] "=&d" (reg1),
+		  [reg2] "=&a" (reg2),
+		  [rc] "+&d" (rc),
+		  [ry] "+&d" (ry),
+		  "+Q" (S390_lowcore.program_new_psw),
+		  "=Q" (old)
+		: [rx] "d" (rx.pair),
+		  [psw_old] "a" (&old),
+		  [psw_pgm] "a" (&S390_lowcore.program_new_psw)
+		: "cc", "memory");
+	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_physmem_online_range(storage_extents[i].start, storage_extents[i].end + 1);
+	return 0;
+}
+
+static int tprot(unsigned long addr)
+{
+	unsigned long reg1, reg2;
+	int rc = -EFAULT;
+	psw_t old;
+
+	asm volatile(
+		"	mvc	0(16,%[psw_old]),0(%[psw_pgm])\n"
+		"	epsw	%[reg1],%[reg2]\n"
+		"	st	%[reg1],0(%[psw_pgm])\n"
+		"	st	%[reg2],4(%[psw_pgm])\n"
+		"	larl	%[reg1],1f\n"
+		"	stg	%[reg1],8(%[psw_pgm])\n"
+		"	tprot	0(%[addr]),0\n"
+		"	ipm	%[rc]\n"
+		"	srl	%[rc],28\n"
+		"1:	mvc	0(16,%[psw_pgm]),0(%[psw_old])\n"
+		: [reg1] "=&d" (reg1),
+		  [reg2] "=&a" (reg2),
+		  [rc] "+&d" (rc),
+		  "=Q" (S390_lowcore.program_new_psw.addr),
+		  "=Q" (old)
+		: [psw_old] "a" (&old),
+		  [psw_pgm] "a" (&S390_lowcore.program_new_psw),
+		  [addr] "a" (addr)
+		: "cc", "memory");
+	return rc;
+}
+
+static unsigned long search_mem_end(void)
+{
+	unsigned long range = 1 << (MAX_PHYSMEM_BITS - 20); /* in 1MB blocks */
+	unsigned long offset = 0;
+	unsigned long pivot;
+
+	while (range > 1) {
+		range >>= 1;
+		pivot = offset + range;
+		if (!tprot(pivot << 20))
+			offset = pivot;
+	}
+	return (offset + 1) << 20;
+}
+
+unsigned long detect_max_physmem_end(void)
+{
+	unsigned long max_physmem_end = 0;
+
+	if (!sclp_early_get_memsize(&max_physmem_end)) {
+		physmem_info.info_source = MEM_DETECT_SCLP_READ_INFO;
+	} else {
+		max_physmem_end = search_mem_end();
+		physmem_info.info_source = MEM_DETECT_BIN_SEARCH;
+	}
+	return max_physmem_end;
+}
+
+void detect_physmem_online_ranges(unsigned long max_physmem_end)
+{
+	if (!sclp_early_read_storage_info()) {
+		physmem_info.info_source = MEM_DETECT_SCLP_STOR_INFO;
+	} else if (!diag260()) {
+		physmem_info.info_source = MEM_DETECT_DIAG260;
+	} else if (max_physmem_end) {
+		add_physmem_online_range(0, max_physmem_end);
+	}
+}
+
+void physmem_set_usable_limit(unsigned long limit)
+{
+	physmem_info.usable = limit;
+	physmem_alloc_pos = limit;
+}
+
+static void die_oom(unsigned long size, unsigned long align, unsigned long min, unsigned long max)
+{
+	unsigned long start, end, total_mem = 0, total_reserved_mem = 0;
+	struct reserved_range *range;
+	enum reserved_range_type t;
+	int i;
+
+	decompressor_printk("Linux version %s\n", kernel_version);
+	if (!is_prot_virt_guest() && early_command_line[0])
+		decompressor_printk("Kernel command line: %s\n", early_command_line);
+	decompressor_printk("Out of memory allocating %lx bytes %lx aligned in range %lx:%lx\n",
+			    size, align, min, max);
+	decompressor_printk("Reserved memory ranges:\n");
+	for_each_physmem_reserved_range(t, range, &start, &end) {
+		decompressor_printk("%016lx %016lx %s\n", start, end, get_rr_type_name(t));
+		total_reserved_mem += end - start;
+	}
+	decompressor_printk("Usable online memory ranges (info source: %s [%x]):\n",
+			    get_physmem_info_source(), physmem_info.info_source);
+	for_each_physmem_usable_range(i, &start, &end) {
+		decompressor_printk("%016lx %016lx\n", start, end);
+		total_mem += end - start;
+	}
+	decompressor_printk("Usable online memory total: %lx Reserved: %lx Free: %lx\n",
+			    total_mem, total_reserved_mem,
+			    total_mem > total_reserved_mem ? total_mem - total_reserved_mem : 0);
+	print_stacktrace(current_frame_address());
+	sclp_early_printk("\n\n -- System halted\n");
+	disabled_wait();
+}
+
+void physmem_reserve(enum reserved_range_type type, unsigned long addr, unsigned long size)
+{
+	physmem_info.reserved[type].start = addr;
+	physmem_info.reserved[type].end = addr + size;
+}
+
+void physmem_free(enum reserved_range_type type)
+{
+	physmem_info.reserved[type].start = 0;
+	physmem_info.reserved[type].end = 0;
+}
+
+static bool __physmem_alloc_intersects(unsigned long addr, unsigned long size,
+				       unsigned long *intersection_start)
+{
+	unsigned long res_addr, res_size;
+	int t;
+
+	for (t = 0; t < RR_MAX; t++) {
+		if (!get_physmem_reserved(t, &res_addr, &res_size))
+			continue;
+		if (intersects(addr, size, res_addr, res_size)) {
+			*intersection_start = res_addr;
+			return true;
+		}
+	}
+	return ipl_report_certs_intersects(addr, size, intersection_start);
+}
+
+static unsigned long __physmem_alloc_range(unsigned long size, unsigned long align,
+					   unsigned long min, unsigned long max,
+					   unsigned int from_ranges, unsigned int *ranges_left,
+					   bool die_on_oom)
+{
+	unsigned int nranges = from_ranges ?: physmem_info.range_count;
+	unsigned long range_start, range_end;
+	unsigned long intersection_start;
+	unsigned long addr, pos = max;
+
+	align = max(align, 8UL);
+	while (nranges) {
+		__get_physmem_range(nranges - 1, &range_start, &range_end, false);
+		pos = min(range_end, pos);
+
+		if (round_up(min, align) + size > pos)
+			break;
+		addr = round_down(pos - size, align);
+		if (range_start > addr) {
+			nranges--;
+			continue;
+		}
+		if (__physmem_alloc_intersects(addr, size, &intersection_start)) {
+			pos = intersection_start;
+			continue;
+		}
+
+		if (ranges_left)
+			*ranges_left = nranges;
+		return addr;
+	}
+	if (die_on_oom)
+		die_oom(size, align, min, max);
+	return 0;
+}
+
+unsigned long physmem_alloc_range(enum reserved_range_type type, unsigned long size,
+				  unsigned long align, unsigned long min, unsigned long max,
+				  bool die_on_oom)
+{
+	unsigned long addr;
+
+	max = min(max, physmem_alloc_pos);
+	addr = __physmem_alloc_range(size, align, min, max, 0, NULL, die_on_oom);
+	if (addr)
+		physmem_reserve(type, addr, size);
+	return addr;
+}
+
+unsigned long physmem_alloc_top_down(enum reserved_range_type type, unsigned long size,
+				     unsigned long align)
+{
+	struct reserved_range *range = &physmem_info.reserved[type];
+	struct reserved_range *new_range;
+	unsigned int ranges_left;
+	unsigned long addr;
+
+	addr = __physmem_alloc_range(size, align, 0, physmem_alloc_pos, physmem_alloc_ranges,
+				     &ranges_left, true);
+	/* if not a consecutive allocation of the same type or first allocation */
+	if (range->start != addr + size) {
+		if (range->end) {
+			physmem_alloc_pos = __physmem_alloc_range(
+				sizeof(struct reserved_range), 0, 0, physmem_alloc_pos,
+				physmem_alloc_ranges, &ranges_left, true);
+			new_range = (struct reserved_range *)physmem_alloc_pos;
+			*new_range = *range;
+			range->chain = new_range;
+			addr = __physmem_alloc_range(size, align, 0, physmem_alloc_pos,
+						     ranges_left, &ranges_left, true);
+		}
+		range->end = addr + size;
+	}
+	range->start = addr;
+	physmem_alloc_pos = addr;
+	physmem_alloc_ranges = ranges_left;
+	return addr;
+}
+
+unsigned long get_physmem_alloc_pos(void)
+{
+	return physmem_alloc_pos;
+}