iov_iter.c: convert iov_iter_npages() to iterate_all_kinds (e0f2dc40) · Commits · e / devices / android_kernel_fairphone_FP5

mm/iov_iter.c

+19 −54

Original line number	Diff line number	Diff line
		@@ -493,32 +493,6 @@ static ssize_t get_pages_alloc_iovec(struct iov_iter *i,
		return (res == n ? len : res * PAGE_SIZE) - *start;
		}

		static int iov_iter_npages_iovec(const struct iov_iter *i, int maxpages)
		{
		size_t offset = i->iov_offset;
		size_t size = i->count;
		const struct iovec *iov = i->iov;
		int npages = 0;
		int n;

		for (n = 0; size && n < i->nr_segs; n++, iov++) {
		unsigned long addr = (unsigned long)iov->iov_base + offset;
		size_t len = iov->iov_len - offset;
		offset = 0;
		if (unlikely(!len)) /* empty segment */
		continue;
		if (len > size)
		len = size;
		npages += (addr + len + PAGE_SIZE - 1) / PAGE_SIZE
		- addr / PAGE_SIZE;
		if (npages >= maxpages) /* don't bother going further */
		return maxpages;
		size -= len;
		offset = 0;
		}
		return min(npages, maxpages);
		}

		static void memcpy_from_page(char to, struct page page, size_t offset, size_t len)
		{
		char *from = kmap_atomic(page);
		@@ -715,30 +689,6 @@ static ssize_t get_pages_alloc_bvec(struct iov_iter *i,
		return len;
		}

		static int iov_iter_npages_bvec(const struct iov_iter *i, int maxpages)
		{
		size_t offset = i->iov_offset;
		size_t size = i->count;
		const struct bio_vec *bvec = i->bvec;
		int npages = 0;
		int n;

		for (n = 0; size && n < i->nr_segs; n++, bvec++) {
		size_t len = bvec->bv_len - offset;
		offset = 0;
		if (unlikely(!len)) /* empty segment */
		continue;
		if (len > size)
		len = size;
		npages++;
		if (npages >= maxpages) /* don't bother going further */
		return maxpages;
		size -= len;
		offset = 0;
		}
		return min(npages, maxpages);
		}

		size_t copy_page_to_iter(struct page *page, size_t offset, size_t bytes,
		struct iov_iter *i)
		{
		@@ -862,9 +812,24 @@ EXPORT_SYMBOL(iov_iter_get_pages_alloc);

		int iov_iter_npages(const struct iov_iter *i, int maxpages)
		{
		if (i->type & ITER_BVEC)
		return iov_iter_npages_bvec(i, maxpages);
		else
		return iov_iter_npages_iovec(i, maxpages);
		size_t size = i->count;
		int npages = 0;

		if (!size)
		return 0;

		iterate_all_kinds(i, size, v, ({
		unsigned long p = (unsigned long)v.iov_base;
		npages += DIV_ROUND_UP(p + v.iov_len, PAGE_SIZE)
		- p / PAGE_SIZE;
		if (npages >= maxpages)
		return maxpages;
		0;}),({
		npages++;
		if (npages >= maxpages)
		return maxpages;
		})
		)
		return npages;
		}
		EXPORT_SYMBOL(iov_iter_npages);