From ae89cf0f34de323c4a7c39bfd9b906acc2635a87 Mon Sep 17 00:00:00 2001 From: Chunwei Chen Date: Thu, 30 Jul 2015 22:19:01 +0800 Subject: [PATCH] Restructure uio to accommodate bio_vec Starting from Linux 4.1, bio_vec will be allowed to pass into filesystem via iter_read/iter_write, so we add a bio_vec field in uio_t to hold it, and use UIO_BVEC in segflg to determine which "vec". Also, to be consistent to newer kernel, we make iovec and bio_vec immutable, and make uio act as an iterator with the new uio_skip field indicating number of bytes to skip in the first segment. Signed-off-by: Chunwei Chen Signed-off-by: Brian Behlendorf Issue zfsonlinux/zfs#3511 Issue zfsonlinux/zfs#3640 Closes #468 --- include/sys/uio.h | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/include/sys/uio.h b/include/sys/uio.h index 25c5f4a01807..404c03774aea 100644 --- a/include/sys/uio.h +++ b/include/sys/uio.h @@ -1,6 +1,7 @@ /*****************************************************************************\ * Copyright (C) 2007-2010 Lawrence Livermore National Security, LLC. * Copyright (C) 2007 The Regents of the University of California. + * Copyright (c) 2015 by Chunwei Chen. All rights reserved. * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER). * Written by Brian Behlendorf . * UCRL-CODE-235197 @@ -26,6 +27,7 @@ #define _SPL_UIO_H #include +#include #include #include @@ -40,10 +42,14 @@ typedef enum uio_seg { UIO_USERSPACE = 0, UIO_SYSSPACE = 1, UIO_USERISPACE= 2, + UIO_BVEC = 3, } uio_seg_t; typedef struct uio { - struct iovec *uio_iov; + union { + const struct iovec *uio_iov; + const struct bio_vec *uio_bvec; + }; int uio_iovcnt; offset_t uio_loffset; uio_seg_t uio_segflg; @@ -51,6 +57,7 @@ typedef struct uio { uint16_t uio_extflg; offset_t uio_limit; ssize_t uio_resid; + size_t uio_skip; } uio_t; typedef struct aio_req {