diff options
author | Sasha Levin <sasha.levin@oracle.com> | 2014-05-16 04:12:43 +0200 |
---|---|---|
committer | Rusty Russell <rusty@rustcorp.com.au> | 2014-05-19 01:56:40 +0200 |
commit | a17597d3b418ca5a394d14724ccfc295cb3186c8 (patch) | |
tree | a2421dacd4bef70854f146bdaf01eb6305160338 /drivers/char | |
parent | virtio-rng: fix boot with virtio-rng device (diff) | |
download | linux-a17597d3b418ca5a394d14724ccfc295cb3186c8.tar.xz linux-a17597d3b418ca5a394d14724ccfc295cb3186c8.zip |
virtio-rng: fixes for device registration/unregistration
There are several fixes in this patch (mostly because it's hard
splitting them up):
- Revert the name field in struct hwrng back to 'const'. Also, don't
do an extra kmalloc for the name - just wasteful.
- Deal with allocation failures properly.
- Use IDA to allocate device number instead of brute forcing one.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Diffstat (limited to 'drivers/char')
-rw-r--r-- | drivers/char/hw_random/virtio-rng.c | 41 |
1 files changed, 23 insertions, 18 deletions
diff --git a/drivers/char/hw_random/virtio-rng.c b/drivers/char/hw_random/virtio-rng.c index 5b25daa7f798..f3e71501de54 100644 --- a/drivers/char/hw_random/virtio-rng.c +++ b/drivers/char/hw_random/virtio-rng.c @@ -25,6 +25,7 @@ #include <linux/virtio_rng.h> #include <linux/module.h> +static DEFINE_IDA(rng_index_ida); struct virtrng_info { struct virtio_device *vdev; @@ -33,6 +34,8 @@ struct virtrng_info { unsigned int data_avail; struct completion have_data; bool busy; + char name[25]; + int index; }; static void random_recv_done(struct virtqueue *vq) @@ -92,41 +95,45 @@ static void virtio_cleanup(struct hwrng *rng) static int probe_common(struct virtio_device *vdev) { - int err, i; + int err, index; struct virtrng_info *vi = NULL; vi = kzalloc(sizeof(struct virtrng_info), GFP_KERNEL); - vi->hwrng.name = kmalloc(40, GFP_KERNEL); + if (!vi) + return -ENOMEM; + + 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.read = virtio_read; - vi->hwrng.cleanup = virtio_cleanup; - vi->hwrng.priv = (unsigned long)vi; + 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. */ vi->vq = virtio_find_single_vq(vdev, random_recv_done, "input"); if (IS_ERR(vi->vq)) { err = PTR_ERR(vi->vq); - kfree(vi->hwrng.name); vi->vq = NULL; kfree(vi); - vi = NULL; + ida_simple_remove(&rng_index_ida, index); return err; } - i = 0; - do { - sprintf(vi->hwrng.name, "virtio_rng.%d", i++); - err = hwrng_register(&vi->hwrng); - } while (err == -EEXIST); - + err = hwrng_register(&vi->hwrng); if (err) { vdev->config->del_vqs(vdev); - kfree(vi->hwrng.name); vi->vq = NULL; kfree(vi); - vi = NULL; + ida_simple_remove(&rng_index_ida, index); return err; } @@ -140,10 +147,8 @@ static void remove_common(struct virtio_device *vdev) vi->busy = false; hwrng_unregister(&vi->hwrng); vdev->config->del_vqs(vdev); - kfree(vi->hwrng.name); - vi->vq = NULL; + ida_simple_remove(&rng_index_ida, vi->index); kfree(vi); - vi = NULL; } static int virtrng_probe(struct virtio_device *vdev) |