powerpc/mm: Use generic_hugetlb_get_unmapped_area()

Use the generic version of arch_hugetlb_get_unmapped_area()
which is now available at all time.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/05f77014c619061638ecc52a0a4136eb04cc2799.1649523076.git.christophe.leroy@csgroup.eu

arch/powerpc/include/asm/book3s/64/hugetlb.h

@@ -8,10 +8,6 @@
  */
 void radix__flush_hugetlb_page(struct vm_area_struct *vma, unsigned long vmaddr);
 void radix__local_flush_hugetlb_page(struct vm_area_struct *vma, unsigned long vmaddr);
-extern unsigned long
-radix__hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
-				unsigned long len, unsigned long pgoff,
-				unsigned long flags);
 
 extern void radix__huge_ptep_modify_prot_commit(struct vm_area_struct *vma,
 						unsigned long addr, pte_t *ptep,

arch/powerpc/mm/book3s64/radix_hugetlbpage.c

@@ -41,61 +41,6 @@ void radix__flush_hugetlb_tlb_range(struct vm_area_struct *vma, unsigned long st
 		radix__flush_tlb_range_psize(vma->vm_mm, start, end, psize);
 }
 
-/*
- * A vairant of hugetlb_get_unmapped_area doing topdown search
- * FIXME!! should we do as x86 does or non hugetlb area does ?
- * ie, use topdown or not based on mmap_is_legacy check ?
- */
-unsigned long
-radix__hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
-				unsigned long len, unsigned long pgoff,
-				unsigned long flags)
-{
-	struct mm_struct *mm = current->mm;
-	struct vm_area_struct *vma;
-	struct hstate *h = hstate_file(file);
-	int fixed = (flags & MAP_FIXED);
-	unsigned long high_limit;
-	struct vm_unmapped_area_info info;
-
-	high_limit = DEFAULT_MAP_WINDOW;
-	if (addr >= high_limit || (fixed && (addr + len > high_limit)))
-		high_limit = TASK_SIZE;
-
-	if (len & ~huge_page_mask(h))
-		return -EINVAL;
-	if (len > high_limit)
-		return -ENOMEM;
-
-	if (fixed) {
-		if (addr > high_limit - len)
-			return -ENOMEM;
-		if (prepare_hugepage_range(file, addr, len))
-			return -EINVAL;
-		return addr;
-	}
-
-	if (addr) {
-		addr = ALIGN(addr, huge_page_size(h));
-		vma = find_vma(mm, addr);
-		if (high_limit - len >= addr && addr >= mmap_min_addr &&
-		    (!vma || addr + len <= vm_start_gap(vma)))
-			return addr;
-	}
-	/*
-	 * We are always doing an topdown search here. Slice code
-	 * does that too.
-	 */
-	info.flags = VM_UNMAPPED_AREA_TOPDOWN;
-	info.length = len;
-	info.low_limit = max(PAGE_SIZE, mmap_min_addr);
-	info.high_limit = mm->mmap_base + (high_limit - DEFAULT_MAP_WINDOW);
-	info.align_mask = PAGE_MASK & ~huge_page_mask(h);
-	info.align_offset = 0;
-
-	return vm_unmapped_area(&info);
-}
-
 void radix__huge_ptep_modify_prot_commit(struct vm_area_struct *vma,
 					 unsigned long addr, pte_t *ptep,
 					 pte_t old_pte, pte_t pte)

arch/powerpc/mm/hugetlbpage.c

@@ -553,11 +553,9 @@ unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
 					unsigned long len, unsigned long pgoff,
 					unsigned long flags)
 {
-#ifdef CONFIG_PPC_RADIX_MMU
 	if (radix_enabled())
-		return radix__hugetlb_get_unmapped_area(file, addr, len,
+		return generic_hugetlb_get_unmapped_area(file, addr, len,
 						       pgoff, flags);
-#endif
 #ifdef CONFIG_PPC_64S_HASH_MMU
 	return slice_get_unmapped_area(addr, len, flags, file_to_psize(file), 1);
 #endif