From d47effe1be0c4fc983306a9c704632e3a087eed8 Mon Sep 17 00:00:00 2001 From: Krishna Kumar Date: Tue, 1 Mar 2011 17:06:37 +0530 Subject: vhost: Cleanup vhost.c and net.c Minor cleanup of vhost.c and net.c to match coding style. Signed-off-by: Krishna Kumar Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 53 +++++++++++++++++++++++++++++++++++---------------- 1 file changed, 37 insertions(+), 16 deletions(-) (limited to 'drivers/vhost/vhost.c') diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index ade0568c07a4..b0cc7f8ca4de 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -41,8 +41,8 @@ static void vhost_poll_func(struct file *file, wait_queue_head_t *wqh, poll_table *pt) { struct vhost_poll *poll; - poll = container_of(pt, struct vhost_poll, table); + poll = container_of(pt, struct vhost_poll, table); poll->wqh = wqh; add_wait_queue(wqh, &poll->wait); } @@ -85,6 +85,7 @@ void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn, void vhost_poll_start(struct vhost_poll *poll, struct file *file) { unsigned long mask; + mask = file->f_op->poll(file, &poll->table); if (mask) vhost_poll_wakeup(&poll->wait, 0, 0, (void *)mask); @@ -101,6 +102,7 @@ static bool vhost_work_seq_done(struct vhost_dev *dev, struct vhost_work *work, unsigned seq) { int left; + spin_lock_irq(&dev->work_lock); left = seq - work->done_seq; spin_unlock_irq(&dev->work_lock); @@ -222,6 +224,7 @@ static int vhost_worker(void *data) static long vhost_dev_alloc_iovecs(struct vhost_dev *dev) { int i; + for (i = 0; i < dev->nvqs; ++i) { dev->vqs[i].indirect = kmalloc(sizeof *dev->vqs[i].indirect * UIO_MAXIOV, GFP_KERNEL); @@ -235,6 +238,7 @@ static long vhost_dev_alloc_iovecs(struct vhost_dev *dev) goto err_nomem; } return 0; + err_nomem: for (; i >= 0; --i) { kfree(dev->vqs[i].indirect); @@ -247,6 +251,7 @@ err_nomem: static void vhost_dev_free_iovecs(struct vhost_dev *dev) { int i; + for (i = 0; i < dev->nvqs; ++i) { kfree(dev->vqs[i].indirect); dev->vqs[i].indirect = NULL; @@ -296,26 +301,28 @@ long vhost_dev_check_owner(struct vhost_dev *dev) } struct vhost_attach_cgroups_struct { - struct vhost_work work; - struct task_struct *owner; - int ret; + struct vhost_work work; + struct task_struct *owner; + int ret; }; static void vhost_attach_cgroups_work(struct vhost_work *work) { - struct vhost_attach_cgroups_struct *s; - s = container_of(work, struct vhost_attach_cgroups_struct, work); - s->ret = cgroup_attach_task_all(s->owner, current); + struct vhost_attach_cgroups_struct *s; + + s = container_of(work, struct vhost_attach_cgroups_struct, work); + s->ret = cgroup_attach_task_all(s->owner, current); } static int vhost_attach_cgroups(struct vhost_dev *dev) { - struct vhost_attach_cgroups_struct attach; - attach.owner = current; - vhost_work_init(&attach.work, vhost_attach_cgroups_work); - vhost_work_queue(dev, &attach.work); - vhost_work_flush(dev, &attach.work); - return attach.ret; + struct vhost_attach_cgroups_struct attach; + + attach.owner = current; + vhost_work_init(&attach.work, vhost_attach_cgroups_work); + vhost_work_queue(dev, &attach.work); + vhost_work_flush(dev, &attach.work); + return attach.ret; } /* Caller should have device mutex */ @@ -323,11 +330,13 @@ static long vhost_dev_set_owner(struct vhost_dev *dev) { struct task_struct *worker; int err; + /* Is there an owner already? */ if (dev->mm) { err = -EBUSY; goto err_mm; } + /* No owner, become one */ dev->mm = get_task_mm(current); worker = kthread_create(vhost_worker, dev, "vhost-%d", current->pid); @@ -380,6 +389,7 @@ long vhost_dev_reset_owner(struct vhost_dev *dev) void vhost_dev_cleanup(struct vhost_dev *dev) { int i; + for (i = 0; i < dev->nvqs; ++i) { if (dev->vqs[i].kick && dev->vqs[i].handle_kick) { vhost_poll_stop(&dev->vqs[i].poll); @@ -421,6 +431,7 @@ void vhost_dev_cleanup(struct vhost_dev *dev) static int log_access_ok(void __user *log_base, u64 addr, unsigned long sz) { u64 a = addr / VHOST_PAGE_SIZE / 8; + /* Make sure 64 bit math will not overflow. */ if (a > ULONG_MAX - (unsigned long)log_base || a + (unsigned long)log_base > ULONG_MAX) @@ -461,6 +472,7 @@ static int memory_access_ok(struct vhost_dev *d, struct vhost_memory *mem, int log_all) { int i; + for (i = 0; i < d->nvqs; ++i) { int ok; mutex_lock(&d->vqs[i].mutex); @@ -527,6 +539,7 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) { struct vhost_memory mem, *newmem, *oldmem; unsigned long size = offsetof(struct vhost_memory, regions); + if (copy_from_user(&mem, m, size)) return -EFAULT; if (mem.padding) @@ -544,7 +557,8 @@ static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m) return -EFAULT; } - if (!memory_access_ok(d, newmem, vhost_has_feature(d, VHOST_F_LOG_ALL))) { + if (!memory_access_ok(d, newmem, + vhost_has_feature(d, VHOST_F_LOG_ALL))) { kfree(newmem); return -EFAULT; } @@ -560,6 +574,7 @@ static int init_used(struct vhost_virtqueue *vq, struct vring_used __user *used) { int r = put_user(vq->used_flags, &used->flags); + if (r) return r; return get_user(vq->last_used_idx, &used->idx); @@ -849,6 +864,7 @@ static const struct vhost_memory_region *find_region(struct vhost_memory *mem, { struct vhost_memory_region *reg; int i; + /* linear search is not brilliant, but we really have on the order of 6 * regions in practice */ for (i = 0; i < mem->nregions; ++i) { @@ -871,6 +887,7 @@ static int set_bit_to_user(int nr, void __user *addr) void *base; int bit = nr + (log % PAGE_SIZE) * 8; int r; + r = get_user_pages_fast(log, 1, 1, &page); if (r < 0) return r; @@ -888,6 +905,7 @@ static int log_write(void __user *log_base, { u64 write_page = write_address / VHOST_PAGE_SIZE; int r; + if (!write_length) return 0; write_length += write_address % VHOST_PAGE_SIZE; @@ -1037,8 +1055,8 @@ static int get_indirect(struct vhost_dev *dev, struct vhost_virtqueue *vq, i, count); return -EINVAL; } - if (unlikely(memcpy_fromiovec((unsigned char *)&desc, vq->indirect, - sizeof desc))) { + if (unlikely(memcpy_fromiovec((unsigned char *)&desc, + vq->indirect, sizeof desc))) { vq_err(vq, "Failed indirect descriptor: idx %d, %zx\n", i, (size_t)indirect->addr + i * sizeof desc); return -EINVAL; @@ -1317,6 +1335,7 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads, void vhost_signal(struct vhost_dev *dev, struct vhost_virtqueue *vq) { __u16 flags; + /* Flush out used index updates. This is paired * with the barrier that the Guest executes when enabling * interrupts. */ @@ -1361,6 +1380,7 @@ bool vhost_enable_notify(struct vhost_virtqueue *vq) { u16 avail_idx; int r; + if (!(vq->used_flags & VRING_USED_F_NO_NOTIFY)) return false; vq->used_flags &= ~VRING_USED_F_NO_NOTIFY; @@ -1387,6 +1407,7 @@ bool vhost_enable_notify(struct vhost_virtqueue *vq) void vhost_disable_notify(struct vhost_virtqueue *vq) { int r; + if (vq->used_flags & VRING_USED_F_NO_NOTIFY) return; vq->used_flags |= VRING_USED_F_NO_NOTIFY; -- cgit v1.2.3 From fcc042a2806064ffcaed7a0c5cb710eca0e99108 Mon Sep 17 00:00:00 2001 From: Michael S. Tsirkin Date: Sun, 6 Mar 2011 13:33:49 +0200 Subject: vhost: copy_from_user -> __copy_from_user copy_from_user is pretty high on perf top profile, replacing it with __copy_from_user helps. It's also safe because we do access_ok checks during setup. Signed-off-by: Michael S. Tsirkin --- drivers/vhost/vhost.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/vhost/vhost.c') diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index b0cc7f8ca4de..2ab291241635 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -1171,7 +1171,7 @@ int vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq, i, vq->num, head); return -EINVAL; } - ret = copy_from_user(&desc, vq->desc + i, sizeof desc); + ret = __copy_from_user(&desc, vq->desc + i, sizeof desc); if (unlikely(ret)) { vq_err(vq, "Failed to get descriptor: idx %d addr %p\n", i, vq->desc + i); -- cgit v1.2.3