parisc: remove mmap linked list from cache handling

Use the VMA iterator instead.

Link: https://lkml.kernel.org/r/20220906194824.2110408-33-Liam.Howlett@oracle.comSigned-off-by: NMatthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: NLiam R. Howlett <Liam.Howlett@Oracle.com>
Acked-by: NVlastimil Babka <vbabka@suse.cz>
Reviewed-by: NDavidlohr Bueso <dave@stgolabs.net>
Tested-by: NYu Zhao <yuzhao@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: SeongJae Park <sj@kernel.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>

arch/parisc/kernel/cache.c

@@ -657,15 +657,20 @@ static inline unsigned long mm_total_size(struct mm_struct *mm)
 {
 	struct vm_area_struct *vma;
 	unsigned long usize = 0;
+	VMA_ITERATOR(vmi, mm, 0);
 
-	for (vma = mm->mmap; vma && usize < parisc_cache_flush_threshold; vma = vma->vm_next)
+	for_each_vma(vmi, vma) {
+		if (usize >= parisc_cache_flush_threshold)
+			break;
 		usize += vma->vm_end - vma->vm_start;
+	}
 	return usize;
 }
 
 void flush_cache_mm(struct mm_struct *mm)
 {
 	struct vm_area_struct *vma;
+	VMA_ITERATOR(vmi, mm, 0);
 
 	/*
 	 * Flushing the whole cache on each cpu takes forever on
@@ -685,7 +690,7 @@ void flush_cache_mm(struct mm_struct *mm)
 	}
 
 	/* Flush mm */
-	for (vma = mm->mmap; vma; vma = vma->vm_next)
+	for_each_vma(vmi, vma)
 		flush_cache_pages(vma, vma->vm_start, vma->vm_end);
 }