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authorVasily Gorbik <gor@linux.ibm.com>2018-04-11 11:56:55 +0200
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2018-10-09 11:21:08 +0200
commit6966d604e2ec4ecf5691aea953538f63597a250d (patch)
treebb97b41e8ee7ead33cb952f690820f13d4dd8ab6
parent17aacfbfa1ae386d3e54d12a13b88b7981e04896 (diff)
downloadlinux-6966d604e2ec4ecf5691aea953538f63597a250d.tar.bz2
s390/mem_detect: move tprot loop to early boot phase
Move memory detection to early boot phase. To store online memory regions "struct mem_detect_info" has been introduced together with for_each_mem_detect_block iterator. mem_detect_info is later converted to memblock. Also introduces sclp_early_get_meminfo function to get maximum physical memory and maximum increment number. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> 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>
-rw-r--r--arch/s390/boot/Makefile2
-rw-r--r--arch/s390/boot/boot.h1
-rw-r--r--arch/s390/boot/mem_detect.c133
-rw-r--r--arch/s390/boot/startup.c1
-rw-r--r--arch/s390/include/asm/mem_detect.h77
-rw-r--r--arch/s390/include/asm/sclp.h1
-rw-r--r--arch/s390/include/asm/setup.h2
-rw-r--r--arch/s390/kernel/setup.c47
-rw-r--r--arch/s390/mm/Makefile3
-rw-r--r--arch/s390/mm/mem_detect.c62
-rw-r--r--drivers/s390/char/sclp_early_core.c17
11 files changed, 277 insertions, 69 deletions
diff --git a/arch/s390/boot/Makefile b/arch/s390/boot/Makefile
index 1b5a95b1ab09..5e2cec6e4b3e 100644
--- a/arch/s390/boot/Makefile
+++ b/arch/s390/boot/Makefile
@@ -27,7 +27,7 @@ endif
CFLAGS_sclp_early_core.o += -I$(srctree)/drivers/s390/char
-obj-y := head.o als.o startup.o ebcdic.o sclp_early_core.o mem.o
+obj-y := head.o als.o startup.o mem_detect.o ebcdic.o sclp_early_core.o mem.o
targets := bzImage startup.a $(obj-y)
subdir- := compressed
diff --git a/arch/s390/boot/boot.h b/arch/s390/boot/boot.h
index 36c93e6cbc3f..808154b99a5d 100644
--- a/arch/s390/boot/boot.h
+++ b/arch/s390/boot/boot.h
@@ -3,5 +3,6 @@
#define BOOT_BOOT_H
void startup_kernel(void);
+void detect_memory(void);
#endif /* BOOT_BOOT_H */
diff --git a/arch/s390/boot/mem_detect.c b/arch/s390/boot/mem_detect.c
new file mode 100644
index 000000000000..920e6fee75de
--- /dev/null
+++ b/arch/s390/boot/mem_detect.c
@@ -0,0 +1,133 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/init.h>
+#include <asm/sclp.h>
+#include <asm/sections.h>
+#include <asm/mem_detect.h>
+#include "compressed/decompressor.h"
+#include "boot.h"
+
+#define CHUNK_READ_WRITE 0
+#define CHUNK_READ_ONLY 1
+
+unsigned long __bootdata(max_physmem_end);
+struct mem_detect_info __bootdata(mem_detect);
+
+/* up to 256 storage elements, 1020 subincrements each */
+#define ENTRIES_EXTENDED_MAX \
+ (256 * (1020 / 2) * sizeof(struct mem_detect_block))
+
+/*
+ * To avoid corrupting old kernel memory during dump, find lowest memory
+ * chunk possible either right after the kernel end (decompressed kernel) or
+ * after initrd (if it is present and there is no hole between the kernel end
+ * and initrd)
+ */
+static void *mem_detect_alloc_extended(void)
+{
+ unsigned long offset = ALIGN(mem_safe_offset(), sizeof(u64));
+
+ if (IS_ENABLED(BLK_DEV_INITRD) && INITRD_START && INITRD_SIZE &&
+ INITRD_START < offset + ENTRIES_EXTENDED_MAX)
+ offset = ALIGN(INITRD_START + INITRD_SIZE, sizeof(u64));
+
+ return (void *)offset;
+}
+
+static struct mem_detect_block *__get_mem_detect_block_ptr(u32 n)
+{
+ if (n < MEM_INLINED_ENTRIES)
+ return &mem_detect.entries[n];
+ if (unlikely(!mem_detect.entries_extended))
+ mem_detect.entries_extended = mem_detect_alloc_extended();
+ return &mem_detect.entries_extended[n - MEM_INLINED_ENTRIES];
+}
+
+/*
+ * sequential calls to add_mem_detect_block with adjacent memory areas
+ * are merged together into single memory block.
+ */
+void add_mem_detect_block(u64 start, u64 end)
+{
+ struct mem_detect_block *block;
+
+ if (mem_detect.count) {
+ block = __get_mem_detect_block_ptr(mem_detect.count - 1);
+ if (block->end == start) {
+ block->end = end;
+ return;
+ }
+ }
+
+ block = __get_mem_detect_block_ptr(mem_detect.count);
+ block->start = start;
+ block->end = end;
+ mem_detect.count++;
+}
+
+static unsigned long get_mem_detect_end(void)
+{
+ if (mem_detect.count)
+ return __get_mem_detect_block_ptr(mem_detect.count - 1)->end;
+ return 0;
+}
+
+static int tprot(unsigned long addr)
+{
+ unsigned long pgm_addr;
+ int rc = -EFAULT;
+ psw_t old = S390_lowcore.program_new_psw;
+
+ S390_lowcore.program_new_psw.mask = __extract_psw();
+ asm volatile(
+ " larl %[pgm_addr],1f\n"
+ " stg %[pgm_addr],%[psw_pgm_addr]\n"
+ " tprot 0(%[addr]),0\n"
+ " ipm %[rc]\n"
+ " srl %[rc],28\n"
+ "1:\n"
+ : [pgm_addr] "=&d"(pgm_addr),
+ [psw_pgm_addr] "=Q"(S390_lowcore.program_new_psw.addr),
+ [rc] "+&d"(rc)
+ : [addr] "a"(addr)
+ : "cc", "memory");
+ S390_lowcore.program_new_psw = old;
+ return rc;
+}
+
+static void scan_memory(unsigned long rzm)
+{
+ unsigned long addr, size;
+ int type;
+
+ if (!rzm)
+ rzm = 1UL << 20;
+
+ addr = 0;
+ do {
+ size = 0;
+ /* assume lowcore is writable */
+ type = addr ? tprot(addr) : CHUNK_READ_WRITE;
+ do {
+ size += rzm;
+ if (max_physmem_end && addr + size >= max_physmem_end)
+ break;
+ } while (type == tprot(addr + size));
+ if (type == CHUNK_READ_WRITE || type == CHUNK_READ_ONLY) {
+ if (max_physmem_end && (addr + size > max_physmem_end))
+ size = max_physmem_end - addr;
+ add_mem_detect_block(addr, addr + size);
+ }
+ addr += size;
+ } while (addr < max_physmem_end);
+}
+
+void detect_memory(void)
+{
+ unsigned long rzm;
+
+ sclp_early_get_meminfo(&max_physmem_end, &rzm);
+ scan_memory(rzm);
+ mem_detect.info_source = MEM_DETECT_TPROT_LOOP;
+ if (!max_physmem_end)
+ max_physmem_end = get_mem_detect_end();
+}
diff --git a/arch/s390/boot/startup.c b/arch/s390/boot/startup.c
index 78651a2c26b0..b0e9f4619203 100644
--- a/arch/s390/boot/startup.c
+++ b/arch/s390/boot/startup.c
@@ -51,6 +51,7 @@ void startup_kernel(void)
rescue_initrd();
sclp_early_read_info();
+ detect_memory();
if (!IS_ENABLED(CONFIG_KERNEL_UNCOMPRESSED)) {
img = decompress_kernel();
memmove((void *)vmlinux.default_lma, img, vmlinux.image_size);
diff --git a/arch/s390/include/asm/mem_detect.h b/arch/s390/include/asm/mem_detect.h
new file mode 100644
index 000000000000..8586adef1c65
--- /dev/null
+++ b/arch/s390/include/asm/mem_detect.h
@@ -0,0 +1,77 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_S390_MEM_DETECT_H
+#define _ASM_S390_MEM_DETECT_H
+
+#include <linux/types.h>
+
+enum mem_info_source {
+ MEM_DETECT_NONE = 0,
+ MEM_DETECT_TPROT_LOOP
+};
+
+struct mem_detect_block {
+ u64 start;
+ u64 end;
+};
+
+/*
+ * Storage element id is defined as 1 byte (up to 256 storage elements).
+ * In practise only storage element id 0 and 1 are used).
+ * According to architecture one storage element could have as much as
+ * 1020 subincrements. 255 mem_detect_blocks are embedded in mem_detect_info.
+ * If more mem_detect_blocks are required, a block of memory from already
+ * known mem_detect_block is taken (entries_extended points to it).
+ */
+#define MEM_INLINED_ENTRIES 255 /* (PAGE_SIZE - 16) / 16 */
+
+struct mem_detect_info {
+ u32 count;
+ u8 info_source;
+ struct mem_detect_block entries[MEM_INLINED_ENTRIES];
+ struct mem_detect_block *entries_extended;
+};
+extern struct mem_detect_info mem_detect;
+
+static inline int __get_mem_detect_block(u32 n, unsigned long *start,
+ unsigned long *end)
+{
+ if (n >= mem_detect.count) {
+ *start = 0;
+ *end = 0;
+ return -1;
+ }
+
+ if (n < MEM_INLINED_ENTRIES) {
+ *start = (unsigned long)mem_detect.entries[n].start;
+ *end = (unsigned long)mem_detect.entries[n].end;
+ } else {
+ *start = (unsigned long)mem_detect.entries_extended[n - MEM_INLINED_ENTRIES].start;
+ *end = (unsigned long)mem_detect.entries_extended[n - MEM_INLINED_ENTRIES].end;
+ }
+ return 0;
+}
+
+/**
+ * for_each_mem_detect_block - early online memory range iterator
+ * @i: an integer used as loop variable
+ * @p_start: ptr to unsigned long for start address of the range
+ * @p_end: ptr to unsigned long for end address of the range
+ *
+ * Walks over detected online memory ranges.
+ */
+#define for_each_mem_detect_block(i, p_start, p_end) \
+ for (i = 0, __get_mem_detect_block(i, p_start, p_end); \
+ i < mem_detect.count; \
+ i++, __get_mem_detect_block(i, p_start, p_end))
+
+static inline void get_mem_detect_reserved(unsigned long *start,
+ unsigned long *size)
+{
+ *start = (unsigned long)mem_detect.entries_extended;
+ if (mem_detect.count > MEM_INLINED_ENTRIES)
+ *size = (mem_detect.count - MEM_INLINED_ENTRIES) * sizeof(struct mem_detect_block);
+ else
+ *size = 0;
+}
+
+#endif
diff --git a/arch/s390/include/asm/sclp.h b/arch/s390/include/asm/sclp.h
index 7df57bd09aa1..c21a8b637a11 100644
--- a/arch/s390/include/asm/sclp.h
+++ b/arch/s390/include/asm/sclp.h
@@ -113,6 +113,7 @@ void sclp_early_printk(const char *s);
void sclp_early_printk_force(const char *s);
void __sclp_early_printk(const char *s, unsigned int len, unsigned int force);
+int sclp_early_get_meminfo(unsigned long *mem, unsigned long *rzm);
int _sclp_get_core_info(struct sclp_core_info *info);
int sclp_core_configure(u8 core);
int sclp_core_deconfigure(u8 core);
diff --git a/arch/s390/include/asm/setup.h b/arch/s390/include/asm/setup.h
index 1d66016f4170..522e4553373a 100644
--- a/arch/s390/include/asm/setup.h
+++ b/arch/s390/include/asm/setup.h
@@ -69,8 +69,6 @@ extern int memory_end_set;
extern unsigned long memory_end;
extern unsigned long max_physmem_end;
-extern void detect_memory_memblock(void);
-
#define MACHINE_IS_VM (S390_lowcore.machine_flags & MACHINE_FLAG_VM)
#define MACHINE_IS_KVM (S390_lowcore.machine_flags & MACHINE_FLAG_KVM)
#define MACHINE_IS_LPAR (S390_lowcore.machine_flags & MACHINE_FLAG_LPAR)
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 67fa7cb8ae80..fdf9bd964dee 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -70,6 +70,7 @@
#include <asm/numa.h>
#include <asm/alternative.h>
#include <asm/nospec-branch.h>
+#include <asm/mem_detect.h>
#include "entry.h"
/*
@@ -91,7 +92,8 @@ unsigned long int_hwcap = 0;
int __initdata memory_end_set;
unsigned long __initdata memory_end;
-unsigned long __initdata max_physmem_end;
+unsigned long __bootdata(max_physmem_end);
+struct mem_detect_info __bootdata(mem_detect);
unsigned long VMALLOC_START;
EXPORT_SYMBOL(VMALLOC_START);
@@ -720,6 +722,45 @@ static void __init reserve_initrd(void)
#endif
}
+static void __init reserve_mem_detect_info(void)
+{
+ unsigned long start, size;
+
+ get_mem_detect_reserved(&start, &size);
+ if (size)
+ memblock_reserve(start, size);
+}
+
+static void __init free_mem_detect_info(void)
+{
+ unsigned long start, size;
+
+ get_mem_detect_reserved(&start, &size);
+ if (size)
+ memblock_free(start, size);
+}
+
+static void __init memblock_physmem_add(phys_addr_t start, phys_addr_t size)
+{
+ memblock_dbg("memblock_physmem_add: [%#016llx-%#016llx]\n",
+ start, start + size - 1);
+ memblock_add_range(&memblock.memory, start, size, 0, 0);
+ memblock_add_range(&memblock.physmem, start, size, 0, 0);
+}
+
+static void __init memblock_add_mem_detect_info(void)
+{
+ unsigned long start, end;
+ int i;
+
+ /* keep memblock lists close to the kernel */
+ memblock_set_bottom_up(true);
+ for_each_mem_detect_block(i, &start, &end)
+ memblock_physmem_add(start, end - start);
+ memblock_set_bottom_up(false);
+ memblock_dump_all();
+}
+
/*
* Check for initrd being in usable memory
*/
@@ -984,11 +1025,13 @@ void __init setup_arch(char **cmdline_p)
reserve_oldmem();
reserve_kernel();
reserve_initrd();
+ reserve_mem_detect_info();
memblock_allow_resize();
/* Get information about *all* installed memory */
- detect_memory_memblock();
+ memblock_add_mem_detect_info();
+ free_mem_detect_info();
remove_oldmem();
/*
diff --git a/arch/s390/mm/Makefile b/arch/s390/mm/Makefile
index 33fe418506bc..83c83c69cab2 100644
--- a/arch/s390/mm/Makefile
+++ b/arch/s390/mm/Makefile
@@ -4,8 +4,7 @@
#
obj-y := init.o fault.o extmem.o mmap.o vmem.o maccess.o
-obj-y += page-states.o gup.o pageattr.o mem_detect.o
-obj-y += pgtable.o pgalloc.o
+obj-y += page-states.o gup.o pageattr.o pgtable.o pgalloc.o
obj-$(CONFIG_CMM) += cmm.o
obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
diff --git a/arch/s390/mm/mem_detect.c b/arch/s390/mm/mem_detect.c
deleted file mode 100644
index 21f6c82c8296..000000000000
--- a/arch/s390/mm/mem_detect.c
+++ /dev/null
@@ -1,62 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright IBM Corp. 2008, 2009
- *
- * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>
- */
-
-#include <linux/kernel.h>
-#include <linux/memblock.h>
-#include <linux/init.h>
-#include <linux/debugfs.h>
-#include <linux/seq_file.h>
-#include <asm/ipl.h>
-#include <asm/sclp.h>
-#include <asm/setup.h>
-
-#define CHUNK_READ_WRITE 0
-#define CHUNK_READ_ONLY 1
-
-static inline void memblock_physmem_add(phys_addr_t start, phys_addr_t size)
-{
- memblock_dbg("memblock_physmem_add: [%#016llx-%#016llx]\n",
- start, start + size - 1);
- memblock_add_range(&memblock.memory, start, size, 0, 0);
- memblock_add_range(&memblock.physmem, start, size, 0, 0);
-}
-
-void __init detect_memory_memblock(void)
-{
- unsigned long memsize, rnmax, rzm, addr, size;
- int type;
-
- rzm = sclp.rzm;
- rnmax = sclp.rnmax;
- memsize = rzm * rnmax;
- if (!rzm)
- rzm = 1UL << 17;
- max_physmem_end = memsize;
- addr = 0;
- /* keep memblock lists close to the kernel */
- memblock_set_bottom_up(true);
- do {
- size = 0;
- /* assume lowcore is writable */
- type = addr ? tprot(addr) : CHUNK_READ_WRITE;
- do {
- size += rzm;
- if (max_physmem_end && addr + size >= max_physmem_end)
- break;
- } while (type == tprot(addr + size));
- if (type == CHUNK_READ_WRITE || type == CHUNK_READ_ONLY) {
- if (max_physmem_end && (addr + size > max_physmem_end))
- size = max_physmem_end - addr;
- memblock_physmem_add(addr, size);
- }
- addr += size;
- } while (addr < max_physmem_end);
- memblock_set_bottom_up(false);
- if (!max_physmem_end)
- max_physmem_end = memblock_end_of_DRAM();
- memblock_dump_all();
-}
diff --git a/drivers/s390/char/sclp_early_core.c b/drivers/s390/char/sclp_early_core.c
index bbea2154a807..4f04ba689771 100644
--- a/drivers/s390/char/sclp_early_core.c
+++ b/drivers/s390/char/sclp_early_core.c
@@ -270,3 +270,20 @@ int __init sclp_early_get_info(struct read_info_sccb *info)
*info = sclp_info_sccb;
return 0;
}
+
+int __init sclp_early_get_meminfo(unsigned long *mem, unsigned long *rzm)
+{
+ unsigned long rnmax;
+ unsigned long rnsize;
+ struct read_info_sccb *sccb = &sclp_info_sccb;
+
+ if (!sclp_info_sccb_valid)
+ return -EIO;
+
+ rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
+ rnsize = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
+ rnsize <<= 20;
+ *mem = rnsize * rnmax;
+ *rzm = rnsize;
+ return 0;
+}