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Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/gi…
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…t/mst/vhost

Pull more vhost fixes from Michael Tsirkin:
 "This fixes some minor issues in the patches that have been merged.

  We also finally drop the workaround disabling event_idx for scsi: it
  was always questionable, and now we know it's not needed.

  There's also a memory leak fix"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  vhost-scsi: Enable VIRTIO_RING_F_EVENT_IDX
  vhost: drop virtio_net.h dependency
  vhost-net: Cleanup vhost_ubuf and vhost_zcopy
  vhost: Remove vhost_enable_zcopy in vhost.h
  vhost: Remove comments for hdr in vhost.h
  vhost: Move VHOST_NET_FEATURES to net.c
  vhost-net: Free ubuf when vhost_dev_set_owner fails
  vhost: Export vhost_dev_set_owner
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Linus Torvalds committed May 7, 2013
2 parents a26ea93 + a18cc42 commit eac8410
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Showing 4 changed files with 71 additions and 51 deletions.
100 changes: 67 additions & 33 deletions drivers/vhost/net.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -58,13 +58,19 @@ MODULE_PARM_DESC(experimental_zcopytx, "Enable Zero Copy TX;"

#define VHOST_DMA_IS_DONE(len) ((len) >= VHOST_DMA_DONE_LEN)

enum {
VHOST_NET_FEATURES = VHOST_FEATURES |
(1ULL << VHOST_NET_F_VIRTIO_NET_HDR) |
(1ULL << VIRTIO_NET_F_MRG_RXBUF),
};

enum {
VHOST_NET_VQ_RX = 0,
VHOST_NET_VQ_TX = 1,
VHOST_NET_VQ_MAX = 2,
};

struct vhost_ubuf_ref {
struct vhost_net_ubuf_ref {
struct kref kref;
wait_queue_head_t wait;
struct vhost_virtqueue *vq;
Expand All @@ -87,7 +93,7 @@ struct vhost_net_virtqueue {
struct ubuf_info *ubuf_info;
/* Reference counting for outstanding ubufs.
* Protected by vq mutex. Writers must also take device mutex. */
struct vhost_ubuf_ref *ubufs;
struct vhost_net_ubuf_ref *ubufs;
};

struct vhost_net {
Expand All @@ -104,24 +110,25 @@ struct vhost_net {
bool tx_flush;
};

static unsigned vhost_zcopy_mask __read_mostly;
static unsigned vhost_net_zcopy_mask __read_mostly;

void vhost_enable_zcopy(int vq)
static void vhost_net_enable_zcopy(int vq)
{
vhost_zcopy_mask |= 0x1 << vq;
vhost_net_zcopy_mask |= 0x1 << vq;
}

static void vhost_zerocopy_done_signal(struct kref *kref)
static void vhost_net_zerocopy_done_signal(struct kref *kref)
{
struct vhost_ubuf_ref *ubufs = container_of(kref, struct vhost_ubuf_ref,
kref);
struct vhost_net_ubuf_ref *ubufs;

ubufs = container_of(kref, struct vhost_net_ubuf_ref, kref);
wake_up(&ubufs->wait);
}

struct vhost_ubuf_ref *vhost_ubuf_alloc(struct vhost_virtqueue *vq,
bool zcopy)
static struct vhost_net_ubuf_ref *
vhost_net_ubuf_alloc(struct vhost_virtqueue *vq, bool zcopy)
{
struct vhost_ubuf_ref *ubufs;
struct vhost_net_ubuf_ref *ubufs;
/* No zero copy backend? Nothing to count. */
if (!zcopy)
return NULL;
Expand All @@ -134,25 +141,38 @@ struct vhost_ubuf_ref *vhost_ubuf_alloc(struct vhost_virtqueue *vq,
return ubufs;
}

void vhost_ubuf_put(struct vhost_ubuf_ref *ubufs)
static void vhost_net_ubuf_put(struct vhost_net_ubuf_ref *ubufs)
{
kref_put(&ubufs->kref, vhost_zerocopy_done_signal);
kref_put(&ubufs->kref, vhost_net_zerocopy_done_signal);
}

void vhost_ubuf_put_and_wait(struct vhost_ubuf_ref *ubufs)
static void vhost_net_ubuf_put_and_wait(struct vhost_net_ubuf_ref *ubufs)
{
kref_put(&ubufs->kref, vhost_zerocopy_done_signal);
kref_put(&ubufs->kref, vhost_net_zerocopy_done_signal);
wait_event(ubufs->wait, !atomic_read(&ubufs->kref.refcount));
kfree(ubufs);
}

static void vhost_net_clear_ubuf_info(struct vhost_net *n)
{

bool zcopy;
int i;

for (i = 0; i < n->dev.nvqs; ++i) {
zcopy = vhost_net_zcopy_mask & (0x1 << i);
if (zcopy)
kfree(n->vqs[i].ubuf_info);
}
}

int vhost_net_set_ubuf_info(struct vhost_net *n)
{
bool zcopy;
int i;

for (i = 0; i < n->dev.nvqs; ++i) {
zcopy = vhost_zcopy_mask & (0x1 << i);
zcopy = vhost_net_zcopy_mask & (0x1 << i);
if (!zcopy)
continue;
n->vqs[i].ubuf_info = kmalloc(sizeof(*n->vqs[i].ubuf_info) *
Expand All @@ -164,7 +184,7 @@ int vhost_net_set_ubuf_info(struct vhost_net *n)

err:
while (i--) {
zcopy = vhost_zcopy_mask & (0x1 << i);
zcopy = vhost_net_zcopy_mask & (0x1 << i);
if (!zcopy)
continue;
kfree(n->vqs[i].ubuf_info);
Expand Down Expand Up @@ -286,7 +306,7 @@ static int vhost_zerocopy_signal_used(struct vhost_net *net,

static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success)
{
struct vhost_ubuf_ref *ubufs = ubuf->ctx;
struct vhost_net_ubuf_ref *ubufs = ubuf->ctx;
struct vhost_virtqueue *vq = ubufs->vq;
int cnt = atomic_read(&ubufs->kref.refcount);

Expand All @@ -303,7 +323,7 @@ static void vhost_zerocopy_callback(struct ubuf_info *ubuf, bool success)
/* set len to mark this desc buffers done DMA */
vq->heads[ubuf->desc].len = success ?
VHOST_DMA_DONE_LEN : VHOST_DMA_FAILED_LEN;
vhost_ubuf_put(ubufs);
vhost_net_ubuf_put(ubufs);
}

/* Expects to be always run from workqueue - which acts as
Expand All @@ -326,7 +346,7 @@ static void handle_tx(struct vhost_net *net)
int err;
size_t hdr_size;
struct socket *sock;
struct vhost_ubuf_ref *uninitialized_var(ubufs);
struct vhost_net_ubuf_ref *uninitialized_var(ubufs);
bool zcopy, zcopy_used;

/* TODO: check that we are running from vhost_worker? */
Expand Down Expand Up @@ -422,7 +442,7 @@ static void handle_tx(struct vhost_net *net)
if (unlikely(err < 0)) {
if (zcopy_used) {
if (ubufs)
vhost_ubuf_put(ubufs);
vhost_net_ubuf_put(ubufs);
nvq->upend_idx = ((unsigned)nvq->upend_idx - 1)
% UIO_MAXIOV;
}
Expand Down Expand Up @@ -776,7 +796,7 @@ static void vhost_net_flush(struct vhost_net *n)
n->tx_flush = true;
mutex_unlock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex);
/* Wait for all lower device DMAs done. */
vhost_ubuf_put_and_wait(n->vqs[VHOST_NET_VQ_TX].ubufs);
vhost_net_ubuf_put_and_wait(n->vqs[VHOST_NET_VQ_TX].ubufs);
mutex_lock(&n->vqs[VHOST_NET_VQ_TX].vq.mutex);
n->tx_flush = false;
kref_init(&n->vqs[VHOST_NET_VQ_TX].ubufs->kref);
Expand Down Expand Up @@ -877,7 +897,7 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd)
struct socket *sock, *oldsock;
struct vhost_virtqueue *vq;
struct vhost_net_virtqueue *nvq;
struct vhost_ubuf_ref *ubufs, *oldubufs = NULL;
struct vhost_net_ubuf_ref *ubufs, *oldubufs = NULL;
int r;

mutex_lock(&n->dev.mutex);
Expand Down Expand Up @@ -908,7 +928,8 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd)
oldsock = rcu_dereference_protected(vq->private_data,
lockdep_is_held(&vq->mutex));
if (sock != oldsock) {
ubufs = vhost_ubuf_alloc(vq, sock && vhost_sock_zcopy(sock));
ubufs = vhost_net_ubuf_alloc(vq,
sock && vhost_sock_zcopy(sock));
if (IS_ERR(ubufs)) {
r = PTR_ERR(ubufs);
goto err_ubufs;
Expand All @@ -934,7 +955,7 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd)
mutex_unlock(&vq->mutex);

if (oldubufs) {
vhost_ubuf_put_and_wait(oldubufs);
vhost_net_ubuf_put_and_wait(oldubufs);
mutex_lock(&vq->mutex);
vhost_zerocopy_signal_used(n, vq);
mutex_unlock(&vq->mutex);
Expand All @@ -952,7 +973,7 @@ static long vhost_net_set_backend(struct vhost_net *n, unsigned index, int fd)
rcu_assign_pointer(vq->private_data, oldsock);
vhost_net_enable_vq(n, vq);
if (ubufs)
vhost_ubuf_put_and_wait(ubufs);
vhost_net_ubuf_put_and_wait(ubufs);
err_ubufs:
fput(sock->file);
err_vq:
Expand Down Expand Up @@ -1027,6 +1048,23 @@ static int vhost_net_set_features(struct vhost_net *n, u64 features)
return 0;
}

static long vhost_net_set_owner(struct vhost_net *n)
{
int r;

mutex_lock(&n->dev.mutex);
r = vhost_net_set_ubuf_info(n);
if (r)
goto out;
r = vhost_dev_set_owner(&n->dev);
if (r)
vhost_net_clear_ubuf_info(n);
vhost_net_flush(n);
out:
mutex_unlock(&n->dev.mutex);
return r;
}

static long vhost_net_ioctl(struct file *f, unsigned int ioctl,
unsigned long arg)
{
Expand Down Expand Up @@ -1055,19 +1093,15 @@ static long vhost_net_ioctl(struct file *f, unsigned int ioctl,
return vhost_net_set_features(n, features);
case VHOST_RESET_OWNER:
return vhost_net_reset_owner(n);
case VHOST_SET_OWNER:
return vhost_net_set_owner(n);
default:
mutex_lock(&n->dev.mutex);
if (ioctl == VHOST_SET_OWNER) {
r = vhost_net_set_ubuf_info(n);
if (r)
goto out;
}
r = vhost_dev_ioctl(&n->dev, ioctl, argp);
if (r == -ENOIOCTLCMD)
r = vhost_vring_ioctl(&n->dev, ioctl, argp);
else
vhost_net_flush(n);
out:
mutex_unlock(&n->dev.mutex);
return r;
}
Expand Down Expand Up @@ -1101,7 +1135,7 @@ static struct miscdevice vhost_net_misc = {
static int vhost_net_init(void)
{
if (experimental_zcopytx)
vhost_enable_zcopy(VHOST_NET_VQ_TX);
vhost_net_enable_zcopy(VHOST_NET_VQ_TX);
return misc_register(&vhost_net_misc);
}
module_init(vhost_net_init);
Expand Down
8 changes: 1 addition & 7 deletions drivers/vhost/scsi.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -162,14 +162,8 @@ enum {
VHOST_SCSI_VQ_IO = 2,
};

/*
* VIRTIO_RING_F_EVENT_IDX seems broken. Not sure the bug is in
* kernel but disabling it helps.
* TODO: debug and remove the workaround.
*/
enum {
VHOST_SCSI_FEATURES = (VHOST_FEATURES & (~VIRTIO_RING_F_EVENT_IDX)) |
(1ULL << VIRTIO_SCSI_F_HOTPLUG)
VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG)
};

#define VHOST_SCSI_MAX_TARGET 256
Expand Down
4 changes: 2 additions & 2 deletions drivers/vhost/vhost.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -13,7 +13,7 @@

#include <linux/eventfd.h>
#include <linux/vhost.h>
#include <linux/virtio_net.h>
#include <linux/socket.h> /* memcpy_fromiovec */
#include <linux/mm.h>
#include <linux/mmu_context.h>
#include <linux/miscdevice.h>
Expand Down Expand Up @@ -344,7 +344,7 @@ static int vhost_attach_cgroups(struct vhost_dev *dev)
}

/* Caller should have device mutex */
static long vhost_dev_set_owner(struct vhost_dev *dev)
long vhost_dev_set_owner(struct vhost_dev *dev)
{
struct task_struct *worker;
int err;
Expand Down
10 changes: 1 addition & 9 deletions drivers/vhost/vhost.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -99,9 +99,6 @@ struct vhost_virtqueue {
u64 log_addr;

struct iovec iov[UIO_MAXIOV];
/* hdr is used to store the virtio header.
* Since each iovec has >= 1 byte length, we never need more than
* header length entries to store the header. */
struct iovec *indirect;
struct vring_used_elem *heads;
/* We use a kind of RCU to access private pointer.
Expand Down Expand Up @@ -135,6 +132,7 @@ struct vhost_dev {
};

long vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs, int nvqs);
long vhost_dev_set_owner(struct vhost_dev *dev);
long vhost_dev_check_owner(struct vhost_dev *);
struct vhost_memory *vhost_dev_reset_owner_prepare(void);
void vhost_dev_reset_owner(struct vhost_dev *, struct vhost_memory *);
Expand Down Expand Up @@ -177,9 +175,6 @@ enum {
(1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
(1ULL << VIRTIO_RING_F_EVENT_IDX) |
(1ULL << VHOST_F_LOG_ALL),
VHOST_NET_FEATURES = VHOST_FEATURES |
(1ULL << VHOST_NET_F_VIRTIO_NET_HDR) |
(1ULL << VIRTIO_NET_F_MRG_RXBUF),
};

static inline int vhost_has_feature(struct vhost_dev *dev, int bit)
Expand All @@ -191,7 +186,4 @@ static inline int vhost_has_feature(struct vhost_dev *dev, int bit)
acked_features = rcu_dereference_index_check(dev->acked_features, 1);
return acked_features & (1 << bit);
}

void vhost_enable_zcopy(int vq);

#endif

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