new primitive: iov_iter_for_each_range() (09cf698a) · Commits · 戴 / test

include/linux/uio.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -244,4 +244,8 @@ int compat_import_iovec(int type, const struct compat_iovec __user * uvector,
		int import_single_range(int type, void __user *buf, size_t len,
		struct iovec iov, struct iov_iter i);

		int iov_iter_for_each_range(struct iov_iter *i, size_t bytes,
		int (f)(struct kvec vec, void *context),
		void *context);

		#endif

+22 −0

Original line number	Diff line number	Diff line
		@@ -1446,3 +1446,25 @@ int import_single_range(int rw, void __user *buf, size_t len,
		return 0;
		}
		EXPORT_SYMBOL(import_single_range);

		int iov_iter_for_each_range(struct iov_iter *i, size_t bytes,
		int (f)(struct kvec vec, void *context),
		void *context)
		{
		struct kvec w;
		int err = -EINVAL;
		if (!bytes)
		return 0;

		iterate_all_kinds(i, bytes, v, -EINVAL, ({
		w.iov_base = kmap(v.bv_page) + v.bv_offset;
		w.iov_len = v.bv_len;
		err = f(&w, context);
		kunmap(v.bv_page);
		err;}), ({
		w = v;
		err = f(&w, context);})
		)
		return err;
		}
		EXPORT_SYMBOL(iov_iter_for_each_range);