arch: simplify several early memory allocations

There are several early memory allocations in arch/ code that use
memblock_phys_alloc() to allocate memory, convert the returned physical
address to the virtual address and then set the allocated memory to
zero.

Exactly the same behaviour can be achieved simply by calling
memblock_alloc(): it allocates the memory in the same way as
memblock_phys_alloc(), then it performs the phys_to_virt() conversion
and clears the allocated memory.

Replace the longer sequence with a simpler call to memblock_alloc().

Link: http://lkml.kernel.org/r/1546248566-14910-6-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Stafford Horne <shorne@gmail.com>
Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/arm/mm/mmu.c

@@ -721,9 +721,7 @@ EXPORT_SYMBOL(phys_mem_access_prot);
 
 static void __init *early_alloc_aligned(unsigned long sz, unsigned long align)
 {
-	void *ptr = __va(memblock_phys_alloc(sz, align));
-	memset(ptr, 0, sz);
-	return ptr;
+	return memblock_alloc(sz, align);
 }
 
 static void __init *early_alloc(unsigned long sz)

arch/c6x/mm/dma-coherent.c

@@ -121,8 +121,6 @@ void arch_dma_free(struct device *dev, size_t size, void *vaddr,
  */
 void __init coherent_mem_init(phys_addr_t start, u32 size)
 {
-	phys_addr_t bitmap_phys;
-
 	if (!size)
 		return;
 
@@ -138,11 +136,8 @@ void __init coherent_mem_init(phys_addr_t start, u32 size)
 	if (dma_size & (PAGE_SIZE - 1))
 		++dma_pages;
 
-	bitmap_phys = memblock_phys_alloc(BITS_TO_LONGS(dma_pages) * sizeof(long),
-					  sizeof(long));
-
-	dma_bitmap = phys_to_virt(bitmap_phys);
-	memset(dma_bitmap, 0, dma_pages * PAGE_SIZE);
+	dma_bitmap = memblock_alloc(BITS_TO_LONGS(dma_pages) * sizeof(long),
+				    sizeof(long));
 }
 
 static void c6x_dma_sync(struct device *dev, phys_addr_t paddr, size_t size,

arch/nds32/mm/init.c

@@ -78,8 +78,7 @@ static void __init map_ram(void)
 		}
 
 		/* Alloc one page for holding PTE's... */
-		pte = (pte_t *) __va(memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE));
-		memset(pte, 0, PAGE_SIZE);
+		pte = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 		set_pmd(pme, __pmd(__pa(pte) + _PAGE_KERNEL_TABLE));
 
 		/* Fill the newly allocated page with PTE'S */
@@ -111,8 +110,7 @@ static void __init fixedrange_init(void)
 	pgd = swapper_pg_dir + pgd_index(vaddr);
 	pud = pud_offset(pgd, vaddr);
 	pmd = pmd_offset(pud, vaddr);
-	fixmap_pmd_p = (pmd_t *) __va(memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE));
-	memset(fixmap_pmd_p, 0, PAGE_SIZE);
+	fixmap_pmd_p = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 	set_pmd(pmd, __pmd(__pa(fixmap_pmd_p) + _PAGE_KERNEL_TABLE));
 
 #ifdef CONFIG_HIGHMEM
@@ -124,8 +122,7 @@ static void __init fixedrange_init(void)
 	pgd = swapper_pg_dir + pgd_index(vaddr);
 	pud = pud_offset(pgd, vaddr);
 	pmd = pmd_offset(pud, vaddr);
-	pte = (pte_t *) __va(memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE));
-	memset(pte, 0, PAGE_SIZE);
+	pte = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 	set_pmd(pmd, __pmd(__pa(pte) + _PAGE_KERNEL_TABLE));
 	pkmap_page_table = pte;
 #endif /* CONFIG_HIGHMEM */
@@ -150,8 +147,7 @@ void __init paging_init(void)
 	fixedrange_init();
 
 	/* allocate space for empty_zero_page */
-	zero_page = __va(memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE));
-	memset(zero_page, 0, PAGE_SIZE);
+	zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
 	zone_sizes_init();
 
 	empty_zero_page = virt_to_page(zero_page);

arch/powerpc/kernel/setup-common.c

@@ -459,8 +459,8 @@ void __init smp_setup_cpu_maps(void)
 
 	DBG("smp_setup_cpu_maps()\n");
 
-	cpu_to_phys_id = __va(memblock_phys_alloc(nr_cpu_ids * sizeof(u32), __alignof__(u32)));
-	memset(cpu_to_phys_id, 0, nr_cpu_ids * sizeof(u32));
+	cpu_to_phys_id = memblock_alloc(nr_cpu_ids * sizeof(u32),
+					__alignof__(u32));
 
 	for_each_node_by_type(dn, "cpu") {
 		const __be32 *intserv;

arch/powerpc/mm/ppc_mmu_32.c

@@ -211,8 +211,7 @@ void __init MMU_init_hw(void)
 	 * Find some memory for the hash table.
 	 */
 	if ( ppc_md.progress ) ppc_md.progress("hash:find piece", 0x322);
-	Hash = __va(memblock_phys_alloc(Hash_size, Hash_size));
-	memset(Hash, 0, Hash_size);
+	Hash = memblock_alloc(Hash_size, Hash_size);
 	_SDR1 = __pa(Hash) | SDR1_LOW_BITS;
 
 	Hash_end = (struct hash_pte *) ((unsigned long)Hash + Hash_size);

arch/powerpc/platforms/powernv/opal.c

@@ -171,8 +171,7 @@ int __init early_init_dt_scan_recoverable_ranges(unsigned long node,
 	/*
 	 * Allocate a buffer to hold the MC recoverable ranges.
 	 */
-	mc_recoverable_range =__va(memblock_phys_alloc(size, __alignof__(u64)));
-	memset(mc_recoverable_range, 0, size);
+	mc_recoverable_range = memblock_alloc(size, __alignof__(u64));
 
 	for (i = 0; i < mc_recoverable_range_len; i++) {
 		mc_recoverable_range[i].start_addr =

arch/s390/numa/numa.c

@@ -62,11 +62,7 @@ int numa_debug_enabled;
  */
 static __init pg_data_t *alloc_node_data(void)
 {
-	pg_data_t *res;
-
-	res = (pg_data_t *) memblock_phys_alloc(sizeof(pg_data_t), 8);
-	memset(res, 0, sizeof(pg_data_t));
-	return res;
+	return memblock_alloc(sizeof(pg_data_t), 8);
 }
 
 /*

arch/sparc/kernel/prom_64.c

@@ -34,16 +34,13 @@
 
 void * __init prom_early_alloc(unsigned long size)
 {
-	unsigned long paddr = memblock_phys_alloc(size, SMP_CACHE_BYTES);
-	void *ret;
+	void *ret = memblock_alloc(size, SMP_CACHE_BYTES);
 
-	if (!paddr) {
+	if (!ret) {
 		prom_printf("prom_early_alloc(%lu) failed\n", size);
 		prom_halt();
 	}
 
-	ret = __va(paddr);
-	memset(ret, 0, size);
 	prom_early_allocated += size;
 
 	return ret;

arch/sparc/mm/init_64.c

@@ -1089,16 +1089,13 @@ static void __init allocate_node_data(int nid)
 	struct pglist_data *p;
 	unsigned long start_pfn, end_pfn;
 #ifdef CONFIG_NEED_MULTIPLE_NODES
-	unsigned long paddr;
 
-	paddr = memblock_phys_alloc_try_nid(sizeof(struct pglist_data),
-					    SMP_CACHE_BYTES, nid);
-	if (!paddr) {
+	NODE_DATA(nid) = memblock_alloc_node(sizeof(struct pglist_data),
+					     SMP_CACHE_BYTES, nid);
+	if (!NODE_DATA(nid)) {
 		prom_printf("Cannot allocate pglist_data for nid[%d]\n", nid);
 		prom_halt();
 	}
-	NODE_DATA(nid) = __va(paddr);
-	memset(NODE_DATA(nid), 0, sizeof(struct pglist_data));
 
 	NODE_DATA(nid)->node_id = nid;
 #endif

arch/unicore32/mm/mmu.c

@@ -143,9 +143,7 @@ static void __init build_mem_type_table(void)
 
 static void __init *early_alloc(unsigned long sz)
 {
-	void *ptr = __va(memblock_phys_alloc(sz, sz));
-	memset(ptr, 0, sz);
-	return ptr;
+	return memblock_alloc(sz, sz);
 }
 
 static pte_t * __init early_pte_alloc(pmd_t *pmd, unsigned long addr,