From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Wang Subject: [PATCH net-next 5/6] vhost: factor out setting vring addr and num Date: Fri, 24 May 2019 04:12:17 -0400 Message-ID: <20190524081218.2502-6-jasowang__814.034130756625$1558685635$gmane$org@redhat.com> References: <20190524081218.2502-1-jasowang@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20190524081218.2502-1-jasowang@redhat.com> 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: mst@redhat.com, jasowang@redhat.com, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org Cc: hch@infradead.org, christophe.de.dinechin@gmail.com, linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org, James.Bottomley@hansenpartnership.com, linux-mm@kvack.org, jglisse@redhat.com, jrdr.linux@gmail.com, davem@davemloft.net, linux-arm-kernel@lists.infradead.org List-Id: virtualization@lists.linuxfoundation.org Factoring vring address and num setting which needs special care for accelerating vq metadata accessing. Signed-off-by: Jason Wang --- drivers/vhost/vhost.c | 177 ++++++++++++++++++++++++------------------ 1 file changed, 103 insertions(+), 74 deletions(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 8605e44a7001..8bbda1777c61 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -1468,6 +1468,104 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) return -EFAULT; } +static long vhost_vring_set_num(struct vhost_dev *d, + struct vhost_virtqueue *vq, + void __user *argp) +{ + struct vhost_vring_state s; + + /* Resizing ring with an active backend? + * You don't want to do that. */ + if (vq->private_data) + return -EBUSY; + + if (copy_from_user(&s, argp, sizeof s)) + return -EFAULT; + + if (!s.num || s.num > 0xffff || (s.num & (s.num - 1))) + return -EINVAL; + vq->num = s.num; + + return 0; +} + +static long vhost_vring_set_addr(struct vhost_dev *d, + struct vhost_virtqueue *vq, + void __user *argp) +{ + struct vhost_vring_addr a; + + if (copy_from_user(&a, argp, sizeof a)) + return -EFAULT; + if (a.flags & ~(0x1 << VHOST_VRING_F_LOG)) + return -EOPNOTSUPP; + + /* For 32bit, verify that the top 32bits of the user + data are set to zero. */ + if ((u64)(unsigned long)a.desc_user_addr != a.desc_user_addr || + (u64)(unsigned long)a.used_user_addr != a.used_user_addr || + (u64)(unsigned long)a.avail_user_addr != a.avail_user_addr) + return -EFAULT; + + /* Make sure it's safe to cast pointers to vring types. */ + BUILD_BUG_ON(__alignof__ *vq->avail > VRING_AVAIL_ALIGN_SIZE); + BUILD_BUG_ON(__alignof__ *vq->used > VRING_USED_ALIGN_SIZE); + if ((a.avail_user_addr & (VRING_AVAIL_ALIGN_SIZE - 1)) || + (a.used_user_addr & (VRING_USED_ALIGN_SIZE - 1)) || + (a.log_guest_addr & (VRING_USED_ALIGN_SIZE - 1))) + return -EINVAL; + + /* We only verify access here if backend is configured. + * If it is not, we don't as size might not have been setup. + * We will verify when backend is configured. */ + if (vq->private_data) { + if (!vq_access_ok(vq, vq->num, + (void __user *)(unsigned long)a.desc_user_addr, + (void __user *)(unsigned long)a.avail_user_addr, + (void __user *)(unsigned long)a.used_user_addr)) + return -EINVAL; + + /* Also validate log access for used ring if enabled. */ + if ((a.flags & (0x1 << VHOST_VRING_F_LOG)) && + !log_access_ok(vq->log_base, a.log_guest_addr, + sizeof *vq->used + + vq->num * sizeof *vq->used->ring)) + return -EINVAL; + } + + vq->log_used = !!(a.flags & (0x1 << VHOST_VRING_F_LOG)); + vq->desc = (void __user *)(unsigned long)a.desc_user_addr; + vq->avail = (void __user *)(unsigned long)a.avail_user_addr; + vq->log_addr = a.log_guest_addr; + vq->used = (void __user *)(unsigned long)a.used_user_addr; + + return 0; +} + +static long vhost_vring_set_num_addr(struct vhost_dev *d, + struct vhost_virtqueue *vq, + unsigned int ioctl, + void __user *argp) +{ + long r; + + mutex_lock(&vq->mutex); + + switch (ioctl) { + case VHOST_SET_VRING_NUM: + r = vhost_vring_set_num(d, vq, argp); + break; + case VHOST_SET_VRING_ADDR: + r = vhost_vring_set_addr(d, vq, argp); + break; + default: + BUG(); + } + + mutex_unlock(&vq->mutex); + + return r; +} long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp) { struct file *eventfp, *filep = NULL; @@ -1477,7 +1575,6 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg struct vhost_virtqueue *vq; struct vhost_vring_state s; struct vhost_vring_file f; - struct vhost_vring_addr a; u32 idx; long r; @@ -1490,26 +1587,14 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg idx = array_index_nospec(idx, d->nvqs); vq = d->vqs[idx]; + if (ioctl == VHOST_SET_VRING_NUM || + ioctl == VHOST_SET_VRING_ADDR) { + return vhost_vring_set_num_addr(d, vq, ioctl, argp); + } + mutex_lock(&vq->mutex); switch (ioctl) { - case VHOST_SET_VRING_NUM: - /* Resizing ring with an active backend? - * You don't want to do that. */ - if (vq->private_data) { - r = -EBUSY; - break; - } - if (copy_from_user(&s, argp, sizeof s)) { - r = -EFAULT; - break; - } - if (!s.num || s.num > 0xffff || (s.num & (s.num - 1))) { - r = -EINVAL; - break; - } - vq->num = s.num; - break; case VHOST_SET_VRING_BASE: /* Moving base with an active backend? * You don't want to do that. */ @@ -1535,62 +1620,6 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg if (copy_to_user(argp, &s, sizeof s)) r = -EFAULT; break; - case VHOST_SET_VRING_ADDR: - if (copy_from_user(&a, argp, sizeof a)) { - r = -EFAULT; - break; - } - if (a.flags & ~(0x1 << VHOST_VRING_F_LOG)) { - r = -EOPNOTSUPP; - break; - } - /* For 32bit, verify that the top 32bits of the user - data are set to zero. */ - if ((u64)(unsigned long)a.desc_user_addr != a.desc_user_addr || - (u64)(unsigned long)a.used_user_addr != a.used_user_addr || - (u64)(unsigned long)a.avail_user_addr != a.avail_user_addr) { - r = -EFAULT; - break; - } - - /* Make sure it's safe to cast pointers to vring types. */ - BUILD_BUG_ON(__alignof__ *vq->avail > VRING_AVAIL_ALIGN_SIZE); - BUILD_BUG_ON(__alignof__ *vq->used > VRING_USED_ALIGN_SIZE); - if ((a.avail_user_addr & (VRING_AVAIL_ALIGN_SIZE - 1)) || - (a.used_user_addr & (VRING_USED_ALIGN_SIZE - 1)) || - (a.log_guest_addr & (VRING_USED_ALIGN_SIZE - 1))) { - r = -EINVAL; - break; - } - - /* We only verify access here if backend is configured. - * If it is not, we don't as size might not have been setup. - * We will verify when backend is configured. */ - if (vq->private_data) { - if (!vq_access_ok(vq, vq->num, - (void __user *)(unsigned long)a.desc_user_addr, - (void __user *)(unsigned long)a.avail_user_addr, - (void __user *)(unsigned long)a.used_user_addr)) { - r = -EINVAL; - break; - } - - /* Also validate log access for used ring if enabled. */ - if ((a.flags & (0x1 << VHOST_VRING_F_LOG)) && - !log_access_ok(vq->log_base, a.log_guest_addr, - sizeof *vq->used + - vq->num * sizeof *vq->used->ring)) { - r = -EINVAL; - break; - } - } - - vq->log_used = !!(a.flags & (0x1 << VHOST_VRING_F_LOG)); - vq->desc = (void __user *)(unsigned long)a.desc_user_addr; - vq->avail = (void __user *)(unsigned long)a.avail_user_addr; - vq->log_addr = a.log_guest_addr; - vq->used = (void __user *)(unsigned long)a.used_user_addr; - break; case VHOST_SET_VRING_KICK: if (copy_from_user(&f, argp, sizeof f)) { r = -EFAULT; -- 2.18.1