arch, drivers: replace for_each_membock() with for_each_mem_range()

There are several occurrences of the following pattern:

	for_each_memblock(memory, reg) {
		start = __pfn_to_phys(memblock_region_memory_base_pfn(reg);
		end = __pfn_to_phys(memblock_region_memory_end_pfn(reg));

		/* do something with start and end */
	}

Using for_each_mem_range() iterator is more appropriate in such cases and
allows simpler and cleaner code.

[akpm@linux-foundation.org: fix arch/arm/mm/pmsa-v7.c build]
[rppt@linux.ibm.com: mips: fix cavium-octeon build caused by memblock refactoring]
  Link: http://lkml.kernel.org/r/20200827124549.GD167163@linux.ibm.com

Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Baoquan He <bhe@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Daniel Axtens <dja@axtens.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Emil Renner Berthing <kernel@esmil.dk>
Cc: Hari Bathini <hbathini@linux.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Link: https://lkml.kernel.org/r/20200818151634.14343-13-rppt@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/arm/kernel/setup.c

@@ -843,19 +843,25 @@ early_param("mem", early_mem);
 
 static void __init request_standard_resources(const struct machine_desc *mdesc)
 {
-	struct memblock_region *region;
+	phys_addr_t start, end, res_end;
 	struct resource *res;
+	u64 i;
 
 	kernel_code.start   = virt_to_phys(_text);
 	kernel_code.end     = virt_to_phys(__init_begin - 1);
 	kernel_data.start   = virt_to_phys(_sdata);
 	kernel_data.end     = virt_to_phys(_end - 1);
 
-	for_each_memblock(memory, region) {
-		phys_addr_t start = __pfn_to_phys(memblock_region_memory_base_pfn(region));
-		phys_addr_t end = __pfn_to_phys(memblock_region_memory_end_pfn(region)) - 1;
+	for_each_mem_range(i, &start, &end) {
 		unsigned long boot_alias_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;
+
 		/*
 		 * Some systems have a special memory alias which is only
 		 * used for booting.  We need to advertise this region to
@@ -869,7 +875,7 @@ static void __init request_standard_resources(const struct machine_desc *mdesc)
 				      __func__, sizeof(*res));
 			res->name = "System RAM (boot alias)";
 			res->start = boot_alias_start;
-			res->end = phys_to_idmap(end);
+			res->end = phys_to_idmap(res_end);
 			res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 			request_resource(&iomem_resource, res);
 		}
@@ -880,7 +886,7 @@ static void __init request_standard_resources(const struct machine_desc *mdesc)
 			      sizeof(*res));
 		res->name  = "System RAM";
 		res->start = start;
-		res->end = end;
+		res->end = res_end;
 		res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY;
 
 		request_resource(&iomem_resource, res);

arch/arm/mm/mmu.c

@@ -1154,9 +1154,8 @@ phys_addr_t arm_lowmem_limit __initdata = 0;
 
 void __init adjust_lowmem_bounds(void)
 {
-	phys_addr_t memblock_limit = 0;
-	u64 vmalloc_limit;
-	struct memblock_region *reg;
+	phys_addr_t block_start, block_end, memblock_limit = 0;
+	u64 vmalloc_limit, i;
 	phys_addr_t lowmem_limit = 0;
 
 	/*
@@ -1172,26 +1171,18 @@ void __init adjust_lowmem_bounds(void)
 	 * The first usable region must be PMD aligned. Mark its start
 	 * as MEMBLOCK_NOMAP if it isn't
 	 */
-	for_each_memblock(memory, reg) {
-		if (!memblock_is_nomap(reg)) {
-			if (!IS_ALIGNED(reg->base, PMD_SIZE)) {
-				phys_addr_t len;
+	for_each_mem_range(i, &block_start, &block_end) {
+		if (!IS_ALIGNED(block_start, PMD_SIZE)) {
+			phys_addr_t len;
 
-				len = round_up(reg->base, PMD_SIZE) - reg->base;
-				memblock_mark_nomap(reg->base, len);
-			}
-			break;
+			len = round_up(block_start, PMD_SIZE) - block_start;
+			memblock_mark_nomap(block_start, len);
 		}
+		break;
 	}
 
-	for_each_memblock(memory, reg) {
-		phys_addr_t block_start = reg->base;
-		phys_addr_t block_end = reg->base + reg->size;
-
-		if (memblock_is_nomap(reg))
-			continue;
-
-		if (reg->base < vmalloc_limit) {
+	for_each_mem_range(i, &block_start, &block_end) {
+		if (block_start < vmalloc_limit) {
 			if (block_end > lowmem_limit)
 				/*
 				 * Compare as u64 to ensure vmalloc_limit does
@@ -1440,19 +1431,15 @@ static void __init kmap_init(void)
 
 static void __init map_lowmem(void)
 {
-	struct memblock_region *reg;
 	phys_addr_t kernel_x_start = round_down(__pa(KERNEL_START), SECTION_SIZE);
 	phys_addr_t kernel_x_end = round_up(__pa(__init_end), SECTION_SIZE);
+	phys_addr_t start, end;
+	u64 i;
 
 	/* Map all the lowmem memory banks. */
-	for_each_memblock(memory, reg) {
-		phys_addr_t start = reg->base;
-		phys_addr_t end = start + reg->size;
+	for_each_mem_range(i, &start, &end) {
 		struct map_desc map;
 
-		if (memblock_is_nomap(reg))
-			continue;
-
 		if (end > arm_lowmem_limit)
 			end = arm_lowmem_limit;
 		if (start >= end)

arch/arm/mm/pmsa-v7.c

@@ -231,12 +231,12 @@ static int __init allocate_region(phys_addr_t base, phys_addr_t size,
 void __init pmsav7_adjust_lowmem_bounds(void)
 {
 	phys_addr_t  specified_mem_size = 0, total_mem_size = 0;
-	struct memblock_region *reg;
-	bool first = true;
 	phys_addr_t mem_start;
 	phys_addr_t mem_end;
+	phys_addr_t reg_start, reg_end;
 	unsigned int mem_max_regions;
-	int num, i;
+	int num;
+	u64 i;
 
 	/* Free-up PMSAv7_PROBE_REGION */
 	mpu_min_region_order = __mpu_min_region_order();
@@ -262,20 +262,19 @@ void __init pmsav7_adjust_lowmem_bounds(void)
 	mem_max_regions -= num;
 #endif
 
-	for_each_memblock(memory, reg) {
-		if (first) {
+	for_each_mem_range(i, &reg_start, &reg_end) {
+		if (i == 0) {
 			phys_addr_t phys_offset = PHYS_OFFSET;
 
 			/*
 			 * Initially only use memory continuous from
 			 * PHYS_OFFSET */
-			if (reg->base != phys_offset)
+			if (reg_start != phys_offset)
 				panic("First memory bank must be contiguous from PHYS_OFFSET");
 
-			mem_start = reg->base;
-			mem_end = reg->base + reg->size;
-			specified_mem_size = reg->size;
-			first = false;
+			mem_start = reg_start;
+			mem_end = reg_end;
+			specified_mem_size = mem_end - mem_start;
 		} else {
 			/*
 			 * memblock auto merges contiguous blocks, remove
@@ -283,8 +282,8 @@ void __init pmsav7_adjust_lowmem_bounds(void)
 			 * blocks separately while iterating)
 			 */
 			pr_notice("Ignoring RAM after %pa, memory at %pa ignored\n",
-				  &mem_end, &reg->base);
-			memblock_remove(reg->base, 0 - reg->base);
+				  &mem_end, &reg_start);
+			memblock_remove(reg_start, 0 - reg_start);
 			break;
 		}
 	}

arch/arm/mm/pmsa-v8.c

@@ -94,20 +94,19 @@ static __init bool is_region_fixed(int number)
 void __init pmsav8_adjust_lowmem_bounds(void)
 {
 	phys_addr_t mem_end;
-	struct memblock_region *reg;
-	bool first = true;
+	phys_addr_t reg_start, reg_end;
+	u64 i;
 
-	for_each_memblock(memory, reg) {
-		if (first) {
+	for_each_mem_range(i, &reg_start, &reg_end) {
+		if (i == 0) {
 			phys_addr_t phys_offset = PHYS_OFFSET;
 
 			/*
 			 * Initially only use memory continuous from
 			 * PHYS_OFFSET */
-			if (reg->base != phys_offset)
+			if (reg_start != phys_offset)
 				panic("First memory bank must be contiguous from PHYS_OFFSET");
-			mem_end = reg->base + reg->size;
-			first = false;
+			mem_end = reg_end;
 		} else {
 			/*
 			 * memblock auto merges contiguous blocks, remove
@@ -115,8 +114,8 @@ void __init pmsav8_adjust_lowmem_bounds(void)
 			 * blocks separately while iterating)
 			 */
 			pr_notice("Ignoring RAM after %pa, memory at %pa ignored\n",
-				  &mem_end, &reg->base);
-			memblock_remove(reg->base, 0 - reg->base);
+				  &mem_end, &reg_start);
+			memblock_remove(reg_start, 0 - reg_start);
 			break;
 		}
 	}

arch/arm/xen/mm.c

@@ -25,11 +25,12 @@
 
 unsigned long xen_get_swiotlb_free_pages(unsigned int order)
 {
-	struct memblock_region *reg;
+	phys_addr_t base;
 	gfp_t flags = __GFP_NOWARN|__GFP_KSWAPD_RECLAIM;
+	u64 i;
 
-	for_each_memblock(memory, reg) {
-		if (reg->base < (phys_addr_t)0xffffffff) {
+	for_each_mem_range(i, &base, NULL) {
+		if (base < (phys_addr_t)0xffffffff) {
 			if (IS_ENABLED(CONFIG_ZONE_DMA32))
 				flags |= __GFP_DMA32;
 			else