Commit 5c02c392 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

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.
parents 3c81bdd9 c77fba9a

drivers/char/hw_random/virtio-rng.c

+67 −38
Original line number Diff line number Diff line
@@ -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)

drivers/s390/kvm/virtio_ccw.c

+37 −12
Original line number Diff line number Diff line
@@ -27,6 +27,7 @@ 
#include <linux/module.h>

#include <linux/io.h>

#include <linux/kvm_para.h>

#include <linux/notifier.h>

#include <asm/setup.h>

#include <asm/irq.h>

#include <asm/cio.h>
@@ -62,6 +63,7 @@ struct virtio_ccw_device { 
	struct vq_config_block *config_block;

	bool is_thinint;

	bool going_away;

	bool device_lost;

	void *airq_info;

};
@@ -1010,11 +1012,14 @@ static void virtio_ccw_remove(struct ccw_device *cdev) 
	unsigned long flags;

	struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);



	if (vcdev && cdev->online)

	if (vcdev && cdev->online) {

		if (vcdev->device_lost)

			virtio_break_device(&vcdev->vdev);

		unregister_virtio_device(&vcdev->vdev);

		spin_lock_irqsave(get_ccwdev_lock(cdev), flags);

		dev_set_drvdata(&cdev->dev, NULL);

		spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);

	}

	cdev->handler = NULL;

}
@@ -1023,12 +1028,14 @@ static int virtio_ccw_offline(struct ccw_device *cdev) 
	unsigned long flags;

	struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);



	if (vcdev) {

	if (!vcdev)

		return 0;

	if (vcdev->device_lost)

		virtio_break_device(&vcdev->vdev);

	unregister_virtio_device(&vcdev->vdev);

	spin_lock_irqsave(get_ccwdev_lock(cdev), flags);

	dev_set_drvdata(&cdev->dev, NULL);

	spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);

	}

	return 0;

}
@@ -1096,8 +1103,26 @@ out_free: 


static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)

{

	/* TODO: Check whether we need special handling here. */

	return 0;

	int rc;

	struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);



	/*

	 * Make sure vcdev is set

	 * i.e. set_offline/remove callback not already running

	 */

	if (!vcdev)

		return NOTIFY_DONE;



	switch (event) {

	case CIO_GONE:

		vcdev->device_lost = true;

		rc = NOTIFY_DONE;

		break;

	default:

		rc = NOTIFY_DONE;

		break;

	}

	return rc;

}



static struct ccw_device_id virtio_ids[] = {

drivers/scsi/virtio_scsi.c

+6 −9
Original line number Diff line number Diff line
@@ -393,11 +393,10 @@ static void virtscsi_event_done(struct virtqueue *vq) 
 * @cmd		: command structure

 * @req_size	: size of the request buffer

 * @resp_size	: size of the response buffer

 * @gfp	: flags to use for memory allocations

 */

static int virtscsi_add_cmd(struct virtqueue *vq,

			    struct virtio_scsi_cmd *cmd,

			    size_t req_size, size_t resp_size, gfp_t gfp)

			    size_t req_size, size_t resp_size)

{

	struct scsi_cmnd *sc = cmd->sc;

	struct scatterlist *sgs[4], req, resp;
@@ -429,19 +428,19 @@ static int virtscsi_add_cmd(struct virtqueue *vq, 
	if (in)

		sgs[out_num + in_num++] = in->sgl;



	return virtqueue_add_sgs(vq, sgs, out_num, in_num, cmd, gfp);

	return virtqueue_add_sgs(vq, sgs, out_num, in_num, cmd, GFP_ATOMIC);

}



static int virtscsi_kick_cmd(struct virtio_scsi_vq *vq,

			     struct virtio_scsi_cmd *cmd,

			     size_t req_size, size_t resp_size, gfp_t gfp)

			     size_t req_size, size_t resp_size)

{

	unsigned long flags;

	int err;

	bool needs_kick = false;



	spin_lock_irqsave(&vq->vq_lock, flags);

	err = virtscsi_add_cmd(vq->vq, cmd, req_size, resp_size, gfp);

	err = virtscsi_add_cmd(vq->vq, cmd, req_size, resp_size);

	if (!err)

		needs_kick = virtqueue_kick_prepare(vq->vq);
@@ -484,8 +483,7 @@ static int virtscsi_queuecommand(struct virtio_scsi *vscsi, 
	memcpy(cmd->req.cmd.cdb, sc->cmnd, sc->cmd_len);



	if (virtscsi_kick_cmd(req_vq, cmd,

			      sizeof cmd->req.cmd, sizeof cmd->resp.cmd,

			      GFP_ATOMIC) != 0)

			      sizeof cmd->req.cmd, sizeof cmd->resp.cmd) != 0)

		return SCSI_MLQUEUE_HOST_BUSY;

	return 0;

}
@@ -542,8 +540,7 @@ static int virtscsi_tmf(struct virtio_scsi *vscsi, struct virtio_scsi_cmd *cmd) 


	cmd->comp = &comp;

	if (virtscsi_kick_cmd(&vscsi->ctrl_vq, cmd,

			      sizeof cmd->req.tmf, sizeof cmd->resp.tmf,

			      GFP_NOIO) < 0)

			      sizeof cmd->req.tmf, sizeof cmd->resp.tmf) < 0)

		goto out;



	wait_for_completion(&comp);

drivers/virtio/virtio_ring.c

+15 −0
Original line number Diff line number Diff line
@@ -865,4 +865,19 @@ bool virtqueue_is_broken(struct virtqueue *_vq) 
}

EXPORT_SYMBOL_GPL(virtqueue_is_broken);



/*

 * This should prevent the device from being used, allowing drivers to

 * recover.  You may need to grab appropriate locks to flush.

 */

void virtio_break_device(struct virtio_device *dev)

{

	struct virtqueue *_vq;



	list_for_each_entry(_vq, &dev->vqs, list) {

		struct vring_virtqueue *vq = to_vvq(_vq);

		vq->broken = true;

	}

}

EXPORT_SYMBOL_GPL(virtio_break_device);



MODULE_LICENSE("GPL");

include/linux/virtio.h

+2 −0
Original line number Diff line number Diff line
@@ -106,6 +106,8 @@ static inline struct virtio_device *dev_to_virtio(struct device *_dev) 
int register_virtio_device(struct virtio_device *dev);

void unregister_virtio_device(struct virtio_device *dev);



void virtio_break_device(struct virtio_device *dev);



/**

 * virtio_driver - operations for a virtio I/O driver

 * @driver: underlying device driver (populate name and owner).

CRA Git | Maintained and supported by SUSTech CRA and CCSE