diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-06-11 21:10:33 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-06-11 21:10:33 -0700 |
commit | 5c02c392cd2320e8d612376d6b72b6548a680923 (patch) | |
tree | 56615b31e21b34414821564cd9bf4c13d7e5d14e /drivers/char/hw_random | |
parent | 3c81bdd9e7ec5c7e28bedf7c7bd3b8911ffee94a (diff) | |
parent | c77fba9ab058d1e96ed51d4215e56905c9ef8d2a (diff) |
Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux
Pull virtio updates from Rusty Russell:
"Main excitement is a virtio_scsi fix for alloc holding spinlock on the
abort path, which I refuse to CC stable since (1) I discovered it
myself, and (2) it's been there forever with no reports"
* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
virtio_scsi: don't call virtqueue_add_sgs(... GFP_NOIO) holding spinlock.
virtio-rng: fixes for device registration/unregistration
virtio-rng: fix boot with virtio-rng device
virtio-rng: support multiple virtio-rng devices
virtio_ccw: introduce device_lost in virtio_ccw_device
virtio: virtio_break_device() to mark all virtqueues broken.
Diffstat (limited to 'drivers/char/hw_random')
-rw-r--r-- | drivers/char/hw_random/virtio-rng.c | 105 |
1 files changed, 67 insertions, 38 deletions
diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c index 2ce0e225e58c..f3e71501de54 100644 --- a/drivers/char/hw_random/virtio-rng.c +++ b/drivers/char/hw_random/virtio-rng.c @@ -25,88 +25,115 @@ #include <linux/virtio_rng.h> #include <linux/module.h> -static struct virtqueue *vq; -static unsigned int data_avail; -static DECLARE_COMPLETION(have_data); -static bool busy; +static DEFINE_IDA(rng_index_ida); + +struct virtrng_info { + struct virtio_device *vdev; + struct hwrng hwrng; + struct virtqueue *vq; + unsigned int data_avail; + struct completion have_data; + bool busy; + char name[25]; + int index; +}; static void random_recv_done(struct virtqueue *vq) { + struct virtrng_info *vi = vq->vdev->priv; + /* We can get spurious callbacks, e.g. shared IRQs + virtio_pci. */ - if (!virtqueue_get_buf(vq, &data_avail)) + if (!virtqueue_get_buf(vi->vq, &vi->data_avail)) return; - complete(&have_data); + complete(&vi->have_data); } /* The host will fill any buffer we give it with sweet, sweet randomness. */ -static void register_buffer(u8 *buf, size_t size) +static void register_buffer(struct virtrng_info *vi, u8 *buf, size_t size) { struct scatterlist sg; sg_init_one(&sg, buf, size); /* There should always be room for one buffer. */ - virtqueue_add_inbuf(vq, &sg, 1, buf, GFP_KERNEL); + virtqueue_add_inbuf(vi->vq, &sg, 1, buf, GFP_KERNEL); - virtqueue_kick(vq); + virtqueue_kick(vi->vq); } static int virtio_read(struct hwrng *rng, void *buf, size_t size, bool wait) { int ret; + struct virtrng_info *vi = (struct virtrng_info *)rng->priv; - if (!busy) { - busy = true; - init_completion(&have_data); - register_buffer(buf, size); + if (!vi->busy) { + vi->busy = true; + init_completion(&vi->have_data); + register_buffer(vi, buf, size); } if (!wait) return 0; - ret = wait_for_completion_killable(&have_data); + ret = wait_for_completion_killable(&vi->have_data); if (ret < 0) return ret; - busy = false; + vi->busy = false; - return data_avail; + return vi->data_avail; } static void virtio_cleanup(struct hwrng *rng) { - if (busy) - wait_for_completion(&have_data); -} + struct virtrng_info *vi = (struct virtrng_info *)rng->priv; - -static struct hwrng virtio_hwrng = { - .name = "virtio", - .cleanup = virtio_cleanup, - .read = virtio_read, -}; + if (vi->busy) + wait_for_completion(&vi->have_data); +} static int probe_common(struct virtio_device *vdev) { - int err; + int err, index; + struct virtrng_info *vi = NULL; + + vi = kzalloc(sizeof(struct virtrng_info), GFP_KERNEL); + if (!vi) + return -ENOMEM; - if (vq) { - /* We only support one device for now */ - return -EBUSY; + vi->index = index = ida_simple_get(&rng_index_ida, 0, 0, GFP_KERNEL); + if (index < 0) { + kfree(vi); + return index; } + sprintf(vi->name, "virtio_rng.%d", index); + init_completion(&vi->have_data); + + vi->hwrng = (struct hwrng) { + .read = virtio_read, + .cleanup = virtio_cleanup, + .priv = (unsigned long)vi, + .name = vi->name, + }; + vdev->priv = vi; + /* We expect a single virtqueue. */ - vq = virtio_find_single_vq(vdev, random_recv_done, "input"); - if (IS_ERR(vq)) { - err = PTR_ERR(vq); - vq = NULL; + vi->vq = virtio_find_single_vq(vdev, random_recv_done, "input"); + if (IS_ERR(vi->vq)) { + err = PTR_ERR(vi->vq); + vi->vq = NULL; + kfree(vi); + ida_simple_remove(&rng_index_ida, index); return err; } - err = hwrng_register(&virtio_hwrng); + err = hwrng_register(&vi->hwrng); if (err) { vdev->config->del_vqs(vdev); - vq = NULL; + vi->vq = NULL; + kfree(vi); + ida_simple_remove(&rng_index_ida, index); return err; } @@ -115,11 +142,13 @@ static int probe_common(struct virtio_device *vdev) static void remove_common(struct virtio_device *vdev) { + struct virtrng_info *vi = vdev->priv; vdev->config->reset(vdev); - busy = false; - hwrng_unregister(&virtio_hwrng); + vi->busy = false; + hwrng_unregister(&vi->hwrng); vdev->config->del_vqs(vdev); - vq = NULL; + ida_simple_remove(&rng_index_ida, vi->index); + kfree(vi); } static int virtrng_probe(struct virtio_device *vdev) |