From f5ff53b4d97c62e63ee2868fd4b8d7896643ee03 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Thu, 19 Jun 2014 15:36:49 -0400 Subject: [PATCH] {macvtap,tun}_get_user(): switch to iov_iter allows to switch macvtap and tun from ->aio_write() to ->write_iter() Signed-off-by: Al Viro --- drivers/net/macvtap.c | 44 +++++++++++++++++++++---------------------- drivers/net/tun.c | 44 +++++++++++++++++++++++-------------------- 2 files changed, 45 insertions(+), 43 deletions(-) diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index 8f8004552d8e..22b4cf2fa108 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -640,12 +640,12 @@ static void macvtap_skb_to_vnet_hdr(const struct sk_buff *skb, /* Get packet from user space buffer */ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m, - const struct iovec *iv, unsigned long total_len, - size_t count, int noblock) + struct iov_iter *from, int noblock) { int good_linear = SKB_MAX_HEAD(NET_IP_ALIGN); struct sk_buff *skb; struct macvlan_dev *vlan; + unsigned long total_len = iov_iter_count(from); unsigned long len = total_len; int err; struct virtio_net_hdr vnet_hdr = { 0 }; @@ -653,6 +653,7 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m, int copylen = 0; bool zerocopy = false; size_t linear; + ssize_t n; if (q->flags & IFF_VNET_HDR) { vnet_hdr_len = q->vnet_hdr_sz; @@ -662,10 +663,11 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m, goto err; len -= vnet_hdr_len; - err = memcpy_fromiovecend((void *)&vnet_hdr, iv, 0, - sizeof(vnet_hdr)); - if (err < 0) + err = -EFAULT; + n = copy_from_iter(&vnet_hdr, sizeof(vnet_hdr), from); + if (n != sizeof(vnet_hdr)) goto err; + iov_iter_advance(from, vnet_hdr_len - sizeof(vnet_hdr)); if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && vnet_hdr.csum_start + vnet_hdr.csum_offset + 2 > vnet_hdr.hdr_len) @@ -680,17 +682,16 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m, if (unlikely(len < ETH_HLEN)) goto err; - err = -EMSGSIZE; - if (unlikely(count > UIO_MAXIOV)) - goto err; - if (m && m->msg_control && sock_flag(&q->sk, SOCK_ZEROCOPY)) { + struct iov_iter i; + copylen = vnet_hdr.hdr_len ? vnet_hdr.hdr_len : GOODCOPY_LEN; if (copylen > good_linear) copylen = good_linear; linear = copylen; - if (iov_pages(iv, vnet_hdr_len + copylen, count) - <= MAX_SKB_FRAGS) + i = *from; + iov_iter_advance(&i, copylen); + if (iov_iter_npages(&i, INT_MAX) <= MAX_SKB_FRAGS) zerocopy = true; } @@ -708,10 +709,9 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m, goto err; if (zerocopy) - err = zerocopy_sg_from_iovec(skb, iv, vnet_hdr_len, count); + err = zerocopy_sg_from_iter(skb, from); else { - err = skb_copy_datagram_from_iovec(skb, 0, iv, vnet_hdr_len, - len); + err = skb_copy_datagram_from_iter(skb, 0, from, len); if (!err && m && m->msg_control) { struct ubuf_info *uarg = m->msg_control; uarg->callback(uarg, false); @@ -764,16 +764,12 @@ err: return err; } -static ssize_t macvtap_aio_write(struct kiocb *iocb, const struct iovec *iv, - unsigned long count, loff_t pos) +static ssize_t macvtap_write_iter(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; - ssize_t result = -ENOLINK; struct macvtap_queue *q = file->private_data; - result = macvtap_get_user(q, NULL, iv, iov_length(iv, count), count, - file->f_flags & O_NONBLOCK); - return result; + return macvtap_get_user(q, NULL, from, file->f_flags & O_NONBLOCK); } /* Put packet to the user space buffer */ @@ -1081,8 +1077,9 @@ static const struct file_operations macvtap_fops = { .open = macvtap_open, .release = macvtap_release, .read = new_sync_read, + .write = new_sync_write, .read_iter = macvtap_read_iter, - .aio_write = macvtap_aio_write, + .write_iter = macvtap_write_iter, .poll = macvtap_poll, .llseek = no_llseek, .unlocked_ioctl = macvtap_ioctl, @@ -1095,8 +1092,9 @@ static int macvtap_sendmsg(struct kiocb *iocb, struct socket *sock, struct msghdr *m, size_t total_len) { struct macvtap_queue *q = container_of(sock, struct macvtap_queue, sock); - return macvtap_get_user(q, m, m->msg_iov, total_len, m->msg_iovlen, - m->msg_flags & MSG_DONTWAIT); + struct iov_iter from; + iov_iter_init(&from, WRITE, m->msg_iov, m->msg_iovlen, total_len); + return macvtap_get_user(q, m, &from, m->msg_flags & MSG_DONTWAIT); } static int macvtap_recvmsg(struct kiocb *iocb, struct socket *sock, diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 405dfdf4f8c8..4b743c612624 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1012,28 +1012,29 @@ static struct sk_buff *tun_alloc_skb(struct tun_file *tfile, /* Get packet from user space buffer */ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, - void *msg_control, const struct iovec *iv, - size_t total_len, size_t count, int noblock) + void *msg_control, struct iov_iter *from, + int noblock) { struct tun_pi pi = { 0, cpu_to_be16(ETH_P_IP) }; struct sk_buff *skb; + size_t total_len = iov_iter_count(from); size_t len = total_len, align = NET_SKB_PAD, linear; struct virtio_net_hdr gso = { 0 }; int good_linear; - int offset = 0; int copylen; bool zerocopy = false; int err; u32 rxhash; + ssize_t n; if (!(tun->flags & TUN_NO_PI)) { if (len < sizeof(pi)) return -EINVAL; len -= sizeof(pi); - if (memcpy_fromiovecend((void *)&pi, iv, 0, sizeof(pi))) + n = copy_from_iter(&pi, sizeof(pi), from); + if (n != sizeof(pi)) return -EFAULT; - offset += sizeof(pi); } if (tun->flags & TUN_VNET_HDR) { @@ -1041,7 +1042,8 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, return -EINVAL; len -= tun->vnet_hdr_sz; - if (memcpy_fromiovecend((void *)&gso, iv, offset, sizeof(gso))) + n = copy_from_iter(&gso, sizeof(gso), from); + if (n != sizeof(gso)) return -EFAULT; if ((gso.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && @@ -1050,7 +1052,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, if (gso.hdr_len > len) return -EINVAL; - offset += tun->vnet_hdr_sz; + iov_iter_advance(from, tun->vnet_hdr_sz); } if ((tun->flags & TUN_TYPE_MASK) == TUN_TAP_DEV) { @@ -1063,6 +1065,8 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, good_linear = SKB_MAX_HEAD(align); if (msg_control) { + struct iov_iter i = *from; + /* There are 256 bytes to be copied in skb, so there is * enough room for skb expand head in case it is used. * The rest of the buffer is mapped from userspace. @@ -1071,7 +1075,8 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, if (copylen > good_linear) copylen = good_linear; linear = copylen; - if (iov_pages(iv, offset + copylen, count) <= MAX_SKB_FRAGS) + iov_iter_advance(&i, copylen); + if (iov_iter_npages(&i, INT_MAX) <= MAX_SKB_FRAGS) zerocopy = true; } @@ -1091,9 +1096,9 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, } if (zerocopy) - err = zerocopy_sg_from_iovec(skb, iv, offset, count); + err = zerocopy_sg_from_iter(skb, from); else { - err = skb_copy_datagram_from_iovec(skb, 0, iv, offset, len); + err = skb_copy_datagram_from_iter(skb, 0, from, len); if (!err && msg_control) { struct ubuf_info *uarg = msg_control; uarg->callback(uarg, false); @@ -1207,8 +1212,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, return total_len; } -static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv, - unsigned long count, loff_t pos) +static ssize_t tun_chr_write_iter(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; struct tun_struct *tun = tun_get(file); @@ -1218,10 +1222,7 @@ static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv, if (!tun) return -EBADFD; - tun_debug(KERN_INFO, tun, "tun_chr_write %ld\n", count); - - result = tun_get_user(tun, tfile, NULL, iv, iov_length(iv, count), - count, file->f_flags & O_NONBLOCK); + result = tun_get_user(tun, tfile, NULL, from, file->f_flags & O_NONBLOCK); tun_put(tun); return result; @@ -1445,11 +1446,14 @@ static int tun_sendmsg(struct kiocb *iocb, struct socket *sock, int ret; struct tun_file *tfile = container_of(sock, struct tun_file, socket); struct tun_struct *tun = __tun_get(tfile); + struct iov_iter from; if (!tun) return -EBADFD; - ret = tun_get_user(tun, tfile, m->msg_control, m->msg_iov, total_len, - m->msg_iovlen, m->msg_flags & MSG_DONTWAIT); + + iov_iter_init(&from, WRITE, m->msg_iov, m->msg_iovlen, total_len); + ret = tun_get_user(tun, tfile, m->msg_control, &from, + m->msg_flags & MSG_DONTWAIT); tun_put(tun); return ret; } @@ -2233,9 +2237,9 @@ static const struct file_operations tun_fops = { .owner = THIS_MODULE, .llseek = no_llseek, .read = new_sync_read, + .write = new_sync_write, .read_iter = tun_chr_read_iter, - .write = do_sync_write, - .aio_write = tun_chr_aio_write, + .write_iter = tun_chr_write_iter, .poll = tun_chr_poll, .unlocked_ioctl = tun_chr_ioctl, #ifdef CONFIG_COMPAT -- 2.34.1