ARM: early_alloc()

Add a common early allocator function, in preparation for switching
over to LMB.  When we do, this function will need to do a little more
than just allocating memory; we need it zero initialized too.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 10 insertions, 8 deletions

diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
index 1676d017a93a..3079d0fd9cea 100644
--- a/arch/arm/mm/mmu.c
+++ b/arch/arm/mm/mmu.c
@@ -487,6 +487,11 @@ static void __init build_mem_type_table(void)
 
 #define vectors_base()  (vectors_high() ? 0xffff0000 : 0)
 
+static void __init *early_alloc(unsigned long sz)
+{
+        return alloc_bootmem_low_pages(sz);
+}
+
 static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
                                   unsigned long end, unsigned long pfn,
                                   const struct mem_type *type)
@@ -494,7 +499,7 @@ static void __init alloc_init_pte(pmd_t *pmd, unsigned long addr,
         pte_t *pte;
 
         if (pmd_none(*pmd)) {
-                pte = alloc_bootmem_low_pages(2 * PTRS_PER_PTE * sizeof(pte_t));
+                pte = early_alloc(2 * PTRS_PER_PTE * sizeof(pte_t));
                 __pmd_populate(pmd, __pa(pte) | type->prot_l1);
         }
 
@@ -873,7 +878,7 @@ static void __init devicemaps_init(struct machine_desc *mdesc)
         /*
          * Allocate the vector page early.
          */
-        vectors = alloc_bootmem_low_pages(PAGE_SIZE);
+        vectors = early_alloc(PAGE_SIZE);
 
         for (addr = VMALLOC_END; addr; addr += PGDIR_SIZE)
                 pmd_clear(pmd_off_k(addr));
@@ -945,7 +950,7 @@ static void __init kmap_init(void)
 {
 #ifdef CONFIG_HIGHMEM
         pmd_t *pmd = pmd_off_k(PKMAP_BASE);
-        pte_t *pte = alloc_bootmem_low_pages(2 * PTRS_PER_PTE * sizeof(pte_t));
+        pte_t *pte = early_alloc(2 * PTRS_PER_PTE * sizeof(pte_t));
         BUG_ON(!pmd_none(*pmd) || !pte);
         __pmd_populate(pmd, __pa(pte) | _PAGE_KERNEL_TABLE);
         pkmap_page_table = pte + PTRS_PER_PTE;
@@ -1005,11 +1010,8 @@ void __init paging_init(struct machine_desc *mdesc)
 
         top_pmd = pmd_off_k(0xffff0000);
 
-        /*
-         * allocate the zero page.  Note that this always succeeds and
-         * returns a zeroed result.
-         */
-        zero_page = alloc_bootmem_low_pages(PAGE_SIZE);
+        /* allocate the zero page. */
+        zero_page = early_alloc(PAGE_SIZE);
         empty_zero_page = virt_to_page(zero_page);
         __flush_dcache_page(NULL, empty_zero_page);
 }