[RFC/RFT PATCH 2/5] memblock: introduce generic memblock_setup_resources()

[Mike Rapoport]

From: Mike Rapoport <rppt@xxxxxxxxxxxxx>

Several architecture have very similar implementation of the setup of the
resource tree. The implementations loop over memory ranges registered in
memblock, request a "System RAM" resource for each range and then reserve
resource rages corresponding to various sections of the kernel image. If
kexec/crash dump are enable the crashk_res region is also reserved.

Move the implementation of resource tree setup from s390 to memblock. It
will be then used by several other architectures as well.

Signed-off-by: Mike Rapoport <rppt@xxxxxxxxxxxxx>
---
 arch/s390/kernel/setup.c | 73 +--------------------------------
 include/linux/memblock.h |  2 +
 mm/memblock.c            | 87 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 90 insertions(+), 72 deletions(-)

diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 30430e7c1b03..6f3c82cc0b0d 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -481,80 +481,9 @@ static void __init setup_lowcore_dat_on(void)
 	__ctl_set_bit(0, 28);
 }
 
-static struct resource code_resource = {
-	.name  = "Kernel code",
-	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
-};
-
-static struct resource data_resource = {
-	.name = "Kernel data",
-	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
-};
-
-static struct resource bss_resource = {
-	.name = "Kernel bss",
-	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
-};
-
-static struct resource __initdata *standard_resources[] = {
-	&code_resource,
-	&data_resource,
-	&bss_resource,
-#ifdef CONFIG_CRASH_DUMP
-	&crashk_res,
-#endif
-};
-
 static void __init setup_resources(void)
 {
-	struct resource *res, *std_res, *sub_res;
-	phys_addr_t start, end;
-	int j;
-	u64 i;
-
-	code_resource.start = (unsigned long) _text;
-	code_resource.end = (unsigned long) _etext - 1;
-	data_resource.start = (unsigned long) _etext;
-	data_resource.end = (unsigned long) _edata - 1;
-	bss_resource.start = (unsigned long) __bss_start;
-	bss_resource.end = (unsigned long) __bss_stop - 1;
-
-	for_each_mem_range(i, &start, &end) {
-		res = memblock_alloc(sizeof(*res), 8);
-		if (!res)
-			panic("%s: Failed to allocate %zu bytes align=0x%x\n",
-			      __func__, sizeof(*res), 8);
-		res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
-
-		res->name = "System RAM";
-		res->start = start;
-		/*
-		 * In memblock, end points to the first byte after the
-		 * range while in resourses, end points to the last byte in
-		 * the range.
-		 */
-		res->end = end - 1;
-		request_resource(&iomem_resource, res);
-
-		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
-			std_res = standard_resources[j];
-			if (!std_res->end || std_res->start < res->start ||
-			    std_res->start > res->end)
-				continue;
-			if (std_res->end > res->end) {
-				sub_res = memblock_alloc(sizeof(*sub_res), 8);
-				if (!sub_res)
-					panic("%s: Failed to allocate %zu bytes align=0x%x\n",
-					      __func__, sizeof(*sub_res), 8);
-				*sub_res = *std_res;
-				sub_res->end = res->end;
-				std_res->start = res->end + 1;
-				request_resource(res, sub_res);
-			} else {
-				request_resource(res, std_res);
-			}
-		}
-	}
+	memblock_setup_resources();
 }
 
 static void __init setup_ident_map_size(void)
diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index 5984fff3f175..44c29ebae842 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -121,6 +121,8 @@ void memblock_free_all(void);
 void reset_node_managed_pages(pg_data_t *pgdat);
 void reset_all_zones_managed_pages(void);
 
+void memblock_setup_resources(void);
+
 /* Low level functions */
 void __next_mem_range(u64 *idx, int nid, enum memblock_flags flags,
 		      struct memblock_type *type_a,
diff --git a/mm/memblock.c b/mm/memblock.c
index afaefa8fc6ab..504435753259 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -16,6 +16,8 @@
 #include <linux/kmemleak.h>
 #include <linux/seq_file.h>
 #include <linux/memblock.h>
+#include <linux/ioport.h>
+#include <linux/kexec.h>
 
 #include <asm/sections.h>
 #include <linux/io.h>
@@ -2062,6 +2064,91 @@ void __init memblock_free_all(void)
 	totalram_pages_add(pages);
 }
 
+static struct resource code_resource = {
+	.name  = "Kernel code",
+	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
+};
+
+static struct resource rodata_resource = {
+	.name = "Kernel rodata",
+	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
+};
+
+static struct resource data_resource = {
+	.name = "Kernel data",
+	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
+};
+
+static struct resource bss_resource = {
+	.name = "Kernel bss",
+	.flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM,
+};
+
+static struct resource __initdata *standard_resources[] = {
+	&code_resource,
+	&rodata_resource,
+	&data_resource,
+	&bss_resource,
+#ifdef CONFIG_KEXEC_CORE
+	&crashk_res,
+#endif
+};
+
+void __init memblock_setup_resources(void)
+{
+	struct resource *res, *kres, *sub_res;
+	phys_addr_t start, end;
+	int j;
+	u64 i;
+
+	code_resource.start = __pa_symbol(_text);
+	code_resource.end = __pa_symbol(_etext)-1;
+	rodata_resource.start = __pa_symbol(__start_rodata);
+	rodata_resource.end = __pa_symbol(__end_rodata)-1;
+	data_resource.start = __pa_symbol(_sdata);
+	data_resource.end = __pa_symbol(_edata)-1;
+	bss_resource.start = __pa_symbol(__bss_start);
+	bss_resource.end = __pa_symbol(__bss_stop)-1;
+
+	for_each_mem_range(i, &start, &end) {
+		res = memblock_alloc(sizeof(*res), 8);
+		if (!res)
+			panic("%s: Failed to allocate %zu bytes align=0x%x\n",
+			      __func__, sizeof(*res), 8);
+		res->flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM;
+
+		res->name = "System RAM";
+		res->start = start;
+
+		/*
+		 * In memblock, end points to the first byte after the
+		 * range while in resourses, end points to the last byte in
+		 * the range.
+		 */
+		res->end = end - 1;
+		request_resource(&iomem_resource, res);
+
+		for (j = 0; j < ARRAY_SIZE(standard_resources); j++) {
+			kres = standard_resources[j];
+			if (!kres->end || kres->start < res->start ||
+			    kres->start > res->end)
+				continue;
+			if (kres->end > res->end) {
+				sub_res = memblock_alloc(sizeof(*sub_res), 8);
+				if (!sub_res)
+					panic("%s: Failed to allocate %zu bytes align=0x%x\n",
+					      __func__, sizeof(*sub_res), 8);
+				*sub_res = *kres;
+				sub_res->end = res->end;
+				kres->start = res->end + 1;
+				request_resource(res, sub_res);
+			} else {
+				request_resource(res, kres);
+			}
+		}
+	}
+}
+
 #if defined(CONFIG_DEBUG_FS) && defined(CONFIG_ARCH_KEEP_MEMBLOCK)
 
 static int memblock_debug_show(struct seq_file *m, void *private)
-- 
2.28.0