From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Michael S. Tsirkin" Subject: Re: [PATCH v3 15/18] vhost: switch vhost get_indirect() to iov_iter, kill memcpy_fromiovec() Date: Wed, 4 Feb 2015 09:52:25 +0100 Message-ID: <20150204085225.GA9920__46226.6231458218$1423039961$gmane$org@redhat.com> References: <20150204063730.GG29656@ZenIV.linux.org.uk> <1423032009-18367-15-git-send-email-viro@ZenIV.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1423032009-18367-15-git-send-email-viro@ZenIV.linux.org.uk> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: virtualization-bounces@lists.linux-foundation.org Errors-To: virtualization-bounces@lists.linux-foundation.org To: Al Viro Cc: netdev@vger.kernel.org, David Miller , kvm@vger.kernel.org, virtualization@lists.linux-foundation.org List-Id: virtualization@lists.linuxfoundation.org On Wed, Feb 04, 2015 at 06:40:06AM +0000, Al Viro wrote: > From: Al Viro > > Cc: Michael S. Tsirkin > Cc: kvm@vger.kernel.org > Cc: virtualization@lists.linux-foundation.org > Signed-off-by: Al Viro Acked-by: Michael S. Tsirkin > --- > drivers/vhost/vhost.c | 6 ++++-- > include/linux/uio.h | 1 - > lib/iovec.c | 25 ------------------------- > 3 files changed, 4 insertions(+), 28 deletions(-) > > diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c > index cb807d0..2ee2826 100644 > --- a/drivers/vhost/vhost.c > +++ b/drivers/vhost/vhost.c > @@ -1125,6 +1125,7 @@ static int get_indirect(struct vhost_virtqueue *vq, > struct vring_desc desc; > unsigned int i = 0, count, found = 0; > u32 len = vhost32_to_cpu(vq, indirect->len); > + struct iov_iter from; > int ret; > > /* Sanity check */ > @@ -1142,6 +1143,7 @@ static int get_indirect(struct vhost_virtqueue *vq, > vq_err(vq, "Translation failure %d in indirect.\n", ret); > return ret; > } > + iov_iter_init(&from, READ, vq->indirect, ret, len); > > /* We will use the result as an address to read from, so most > * architectures only need a compiler barrier here. */ > @@ -1164,8 +1166,8 @@ static int get_indirect(struct vhost_virtqueue *vq, > i, count); > return -EINVAL; > } > - if (unlikely(memcpy_fromiovec((unsigned char *)&desc, > - vq->indirect, sizeof desc))) { > + if (unlikely(copy_from_iter(&desc, sizeof(desc), &from) != > + sizeof(desc))) { > vq_err(vq, "Failed indirect descriptor: idx %d, %zx\n", > i, (size_t)vhost64_to_cpu(vq, indirect->addr) + i * sizeof desc); > return -EINVAL; > diff --git a/include/linux/uio.h b/include/linux/uio.h > index 1c5e453..af3439f 100644 > --- a/include/linux/uio.h > +++ b/include/linux/uio.h > @@ -135,7 +135,6 @@ static inline void iov_iter_reexpand(struct iov_iter *i, size_t count) > size_t csum_and_copy_to_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i); > size_t csum_and_copy_from_iter(void *addr, size_t bytes, __wsum *csum, struct iov_iter *i); > > -int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len); > int memcpy_fromiovecend(unsigned char *kdata, const struct iovec *iov, > int offset, int len); > int memcpy_toiovecend(const struct iovec *v, unsigned char *kdata, > diff --git a/lib/iovec.c b/lib/iovec.c > index 2d99cb4..4a90875 100644 > --- a/lib/iovec.c > +++ b/lib/iovec.c > @@ -3,31 +3,6 @@ > #include > > /* > - * Copy iovec to kernel. Returns -EFAULT on error. > - * > - * Note: this modifies the original iovec. > - */ > - > -int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len) > -{ > - while (len > 0) { > - if (iov->iov_len) { > - int copy = min_t(unsigned int, len, iov->iov_len); > - if (copy_from_user(kdata, iov->iov_base, copy)) > - return -EFAULT; > - len -= copy; > - kdata += copy; > - iov->iov_base += copy; > - iov->iov_len -= copy; > - } > - iov++; > - } > - > - return 0; > -} > -EXPORT_SYMBOL(memcpy_fromiovec); > - > -/* > * Copy kernel to iovec. Returns -EFAULT on error. > */ > > -- > 2.1.4