Merge git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus
* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
virtio_net: delay TX callbacks
virtio: add api for delayed callbacks
virtio_test: support event index
vhost: support event index
virtio_ring: support event idx feature
virtio ring: inline function to check for events
virtio: event index interface
virtio: add full three-clause BSD text to headers.
virtio balloon: kill tell-host-first logic
virtio console: don't manually set or finalize VIRTIO_CONSOLE_F_MULTIPORT.
drivers, block: virtio_blk: Replace cryptic number with the macro
virtio_blk: allow re-reading config space at runtime
lguest: remove support for VIRTIO_F_NOTIFY_ON_EMPTY.
lguest: fix up compilation after move
lguest: fix timer interrupt setup
diff --git a/Documentation/virtual/lguest/Makefile b/Documentation/virtual/lguest/Makefile
index bebac6b..0ac3420 100644
--- a/Documentation/virtual/lguest/Makefile
+++ b/Documentation/virtual/lguest/Makefile
@@ -1,5 +1,5 @@
# This creates the demonstration utility "lguest" which runs a Linux guest.
-# Missing headers? Add "-I../../include -I../../arch/x86/include"
+# Missing headers? Add "-I../../../include -I../../../arch/x86/include"
CFLAGS:=-m32 -Wall -Wmissing-declarations -Wmissing-prototypes -O3 -U_FORTIFY_SOURCE
all: lguest
diff --git a/Documentation/virtual/lguest/lguest.c b/Documentation/virtual/lguest/lguest.c
index d9da7e1..cd9d6af 100644
--- a/Documentation/virtual/lguest/lguest.c
+++ b/Documentation/virtual/lguest/lguest.c
@@ -49,7 +49,7 @@
#include <linux/virtio_rng.h>
#include <linux/virtio_ring.h>
#include <asm/bootparam.h>
-#include "../../include/linux/lguest_launcher.h"
+#include "../../../include/linux/lguest_launcher.h"
/*L:110
* We can ignore the 42 include files we need for this program, but I do want
* to draw attention to the use of kernel-style types.
@@ -135,9 +135,6 @@
/* Is it operational */
bool running;
- /* Does Guest want an intrrupt on empty? */
- bool irq_on_empty;
-
/* Device-specific data. */
void *priv;
};
@@ -637,10 +634,7 @@
/* If they don't want an interrupt, don't send one... */
if (vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT) {
- /* ... unless they've asked us to force one on empty. */
- if (!vq->dev->irq_on_empty
- || lg_last_avail(vq) != vq->vring.avail->idx)
- return;
+ return;
}
/* Send the Guest an interrupt tell them we used something up. */
@@ -1057,15 +1051,6 @@
close(vq->eventfd);
}
-static bool accepted_feature(struct device *dev, unsigned int bit)
-{
- const u8 *features = get_feature_bits(dev) + dev->feature_len;
-
- if (dev->feature_len < bit / CHAR_BIT)
- return false;
- return features[bit / CHAR_BIT] & (1 << (bit % CHAR_BIT));
-}
-
static void start_device(struct device *dev)
{
unsigned int i;
@@ -1079,8 +1064,6 @@
verbose(" %02x", get_feature_bits(dev)
[dev->feature_len+i]);
- dev->irq_on_empty = accepted_feature(dev, VIRTIO_F_NOTIFY_ON_EMPTY);
-
for (vq = dev->vq; vq; vq = vq->next) {
if (vq->service)
create_thread(vq);
@@ -1564,7 +1547,6 @@
/* Set up the tun device. */
configure_device(ipfd, tapif, ip);
- add_feature(dev, VIRTIO_F_NOTIFY_ON_EMPTY);
/* Expect Guest to handle everything except UFO */
add_feature(dev, VIRTIO_NET_F_CSUM);
add_feature(dev, VIRTIO_NET_F_GUEST_CSUM);
diff --git a/arch/x86/lguest/boot.c b/arch/x86/lguest/boot.c
index e191c09..db832fd 100644
--- a/arch/x86/lguest/boot.c
+++ b/arch/x86/lguest/boot.c
@@ -993,6 +993,7 @@
static void lguest_time_init(void)
{
/* Set up the timer interrupt (0) to go to our simple timer routine */
+ lguest_setup_irq(0);
irq_set_handler(0, lguest_time_irq);
clocksource_register_hz(&lguest_clock, NSEC_PER_SEC);
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 6ecf89c..079c088 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -6,10 +6,13 @@
#include <linux/virtio.h>
#include <linux/virtio_blk.h>
#include <linux/scatterlist.h>
+#include <linux/string_helpers.h>
+#include <scsi/scsi_cmnd.h>
#define PART_BITS 4
static int major, index;
+struct workqueue_struct *virtblk_wq;
struct virtio_blk
{
@@ -26,6 +29,9 @@
mempool_t *pool;
+ /* Process context for config space updates */
+ struct work_struct config_work;
+
/* What host tells us, plus 2 for header & tailer. */
unsigned int sg_elems;
@@ -141,7 +147,7 @@
num = blk_rq_map_sg(q, vbr->req, vblk->sg + out);
if (vbr->req->cmd_type == REQ_TYPE_BLOCK_PC) {
- sg_set_buf(&vblk->sg[num + out + in++], vbr->req->sense, 96);
+ sg_set_buf(&vblk->sg[num + out + in++], vbr->req->sense, SCSI_SENSE_BUFFERSIZE);
sg_set_buf(&vblk->sg[num + out + in++], &vbr->in_hdr,
sizeof(vbr->in_hdr));
}
@@ -291,6 +297,46 @@
}
DEVICE_ATTR(serial, S_IRUGO, virtblk_serial_show, NULL);
+static void virtblk_config_changed_work(struct work_struct *work)
+{
+ struct virtio_blk *vblk =
+ container_of(work, struct virtio_blk, config_work);
+ struct virtio_device *vdev = vblk->vdev;
+ struct request_queue *q = vblk->disk->queue;
+ char cap_str_2[10], cap_str_10[10];
+ u64 capacity, size;
+
+ /* Host must always specify the capacity. */
+ vdev->config->get(vdev, offsetof(struct virtio_blk_config, capacity),
+ &capacity, sizeof(capacity));
+
+ /* If capacity is too big, truncate with warning. */
+ if ((sector_t)capacity != capacity) {
+ dev_warn(&vdev->dev, "Capacity %llu too large: truncating\n",
+ (unsigned long long)capacity);
+ capacity = (sector_t)-1;
+ }
+
+ size = capacity * queue_logical_block_size(q);
+ string_get_size(size, STRING_UNITS_2, cap_str_2, sizeof(cap_str_2));
+ string_get_size(size, STRING_UNITS_10, cap_str_10, sizeof(cap_str_10));
+
+ dev_notice(&vdev->dev,
+ "new size: %llu %d-byte logical blocks (%s/%s)\n",
+ (unsigned long long)capacity,
+ queue_logical_block_size(q),
+ cap_str_10, cap_str_2);
+
+ set_capacity(vblk->disk, capacity);
+}
+
+static void virtblk_config_changed(struct virtio_device *vdev)
+{
+ struct virtio_blk *vblk = vdev->priv;
+
+ queue_work(virtblk_wq, &vblk->config_work);
+}
+
static int __devinit virtblk_probe(struct virtio_device *vdev)
{
struct virtio_blk *vblk;
@@ -327,6 +373,7 @@
vblk->vdev = vdev;
vblk->sg_elems = sg_elems;
sg_init_table(vblk->sg, vblk->sg_elems);
+ INIT_WORK(&vblk->config_work, virtblk_config_changed_work);
/* We expect one virtqueue, for output. */
vblk->vq = virtio_find_single_vq(vdev, blk_done, "requests");
@@ -477,6 +524,8 @@
{
struct virtio_blk *vblk = vdev->priv;
+ flush_work(&vblk->config_work);
+
/* Nothing should be pending. */
BUG_ON(!list_empty(&vblk->reqs));
@@ -508,27 +557,47 @@
* Use __refdata to avoid this warning.
*/
static struct virtio_driver __refdata virtio_blk = {
- .feature_table = features,
- .feature_table_size = ARRAY_SIZE(features),
- .driver.name = KBUILD_MODNAME,
- .driver.owner = THIS_MODULE,
- .id_table = id_table,
- .probe = virtblk_probe,
- .remove = __devexit_p(virtblk_remove),
+ .feature_table = features,
+ .feature_table_size = ARRAY_SIZE(features),
+ .driver.name = KBUILD_MODNAME,
+ .driver.owner = THIS_MODULE,
+ .id_table = id_table,
+ .probe = virtblk_probe,
+ .remove = __devexit_p(virtblk_remove),
+ .config_changed = virtblk_config_changed,
};
static int __init init(void)
{
+ int error;
+
+ virtblk_wq = alloc_workqueue("virtio-blk", 0, 0);
+ if (!virtblk_wq)
+ return -ENOMEM;
+
major = register_blkdev(0, "virtblk");
- if (major < 0)
- return major;
- return register_virtio_driver(&virtio_blk);
+ if (major < 0) {
+ error = major;
+ goto out_destroy_workqueue;
+ }
+
+ error = register_virtio_driver(&virtio_blk);
+ if (error)
+ goto out_unregister_blkdev;
+ return 0;
+
+out_unregister_blkdev:
+ unregister_blkdev(major, "virtblk");
+out_destroy_workqueue:
+ destroy_workqueue(virtblk_wq);
+ return error;
}
static void __exit fini(void)
{
unregister_blkdev(major, "virtblk");
unregister_virtio_driver(&virtio_blk);
+ destroy_workqueue(virtblk_wq);
}
module_init(init);
module_exit(fini);
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
index 838568a..fb68b12 100644
--- a/drivers/char/virtio_console.c
+++ b/drivers/char/virtio_console.c
@@ -1677,17 +1677,12 @@
portdev->config.max_nr_ports = 1;
if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_MULTIPORT)) {
multiport = true;
- vdev->features[0] |= 1 << VIRTIO_CONSOLE_F_MULTIPORT;
-
vdev->config->get(vdev, offsetof(struct virtio_console_config,
max_nr_ports),
&portdev->config.max_nr_ports,
sizeof(portdev->config.max_nr_ports));
}
- /* Let the Host know we support multiple ports.*/
- vdev->config->finalize_features(vdev);
-
err = init_vqs(portdev);
if (err < 0) {
dev_err(&vdev->dev, "Error %d initializing vqs\n", err);
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 0cb0b06..f685324 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -609,7 +609,7 @@
* before it gets out of hand. Naturally, this wastes entries. */
if (capacity < 2+MAX_SKB_FRAGS) {
netif_stop_queue(dev);
- if (unlikely(!virtqueue_enable_cb(vi->svq))) {
+ if (unlikely(!virtqueue_enable_cb_delayed(vi->svq))) {
/* More just got used, free them then recheck. */
capacity += free_old_xmit_skbs(vi);
if (capacity >= 2+MAX_SKB_FRAGS) {
diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c
index 2f7c76a..e224a92 100644
--- a/drivers/vhost/net.c
+++ b/drivers/vhost/net.c
@@ -144,7 +144,7 @@
}
mutex_lock(&vq->mutex);
- vhost_disable_notify(vq);
+ vhost_disable_notify(&net->dev, vq);
if (wmem < sock->sk->sk_sndbuf / 2)
tx_poll_stop(net);
@@ -166,8 +166,8 @@
set_bit(SOCK_ASYNC_NOSPACE, &sock->flags);
break;
}
- if (unlikely(vhost_enable_notify(vq))) {
- vhost_disable_notify(vq);
+ if (unlikely(vhost_enable_notify(&net->dev, vq))) {
+ vhost_disable_notify(&net->dev, vq);
continue;
}
break;
@@ -315,7 +315,7 @@
return;
mutex_lock(&vq->mutex);
- vhost_disable_notify(vq);
+ vhost_disable_notify(&net->dev, vq);
vhost_hlen = vq->vhost_hlen;
sock_hlen = vq->sock_hlen;
@@ -334,10 +334,10 @@
break;
/* OK, now we need to know about added descriptors. */
if (!headcount) {
- if (unlikely(vhost_enable_notify(vq))) {
+ if (unlikely(vhost_enable_notify(&net->dev, vq))) {
/* They have slipped one in as we were
* doing that: check again. */
- vhost_disable_notify(vq);
+ vhost_disable_notify(&net->dev, vq);
continue;
}
/* Nothing new? Wait for eventfd to tell us
diff --git a/drivers/vhost/test.c b/drivers/vhost/test.c
index 099f302..734e1d7 100644
--- a/drivers/vhost/test.c
+++ b/drivers/vhost/test.c
@@ -49,7 +49,7 @@
return;
mutex_lock(&vq->mutex);
- vhost_disable_notify(vq);
+ vhost_disable_notify(&n->dev, vq);
for (;;) {
head = vhost_get_vq_desc(&n->dev, vq, vq->iov,
@@ -61,8 +61,8 @@
break;
/* Nothing new? Wait for eventfd to tell us they refilled. */
if (head == vq->num) {
- if (unlikely(vhost_enable_notify(vq))) {
- vhost_disable_notify(vq);
+ if (unlikely(vhost_enable_notify(&n->dev, vq))) {
+ vhost_disable_notify(&n->dev, vq);
continue;
}
break;
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 7aa4eea..ea966b3 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -37,6 +37,9 @@
VHOST_MEMORY_F_LOG = 0x1,
};
+#define vhost_used_event(vq) ((u16 __user *)&vq->avail->ring[vq->num])
+#define vhost_avail_event(vq) ((u16 __user *)&vq->used->ring[vq->num])
+
static void vhost_poll_func(struct file *file, wait_queue_head_t *wqh,
poll_table *pt)
{
@@ -161,6 +164,8 @@
vq->last_avail_idx = 0;
vq->avail_idx = 0;
vq->last_used_idx = 0;
+ vq->signalled_used = 0;
+ vq->signalled_used_valid = false;
vq->used_flags = 0;
vq->log_used = false;
vq->log_addr = -1ull;
@@ -489,16 +494,17 @@
return 1;
}
-static int vq_access_ok(unsigned int num,
+static int vq_access_ok(struct vhost_dev *d, unsigned int num,
struct vring_desc __user *desc,
struct vring_avail __user *avail,
struct vring_used __user *used)
{
+ size_t s = vhost_has_feature(d, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
return access_ok(VERIFY_READ, desc, num * sizeof *desc) &&
access_ok(VERIFY_READ, avail,
- sizeof *avail + num * sizeof *avail->ring) &&
+ sizeof *avail + num * sizeof *avail->ring + s) &&
access_ok(VERIFY_WRITE, used,
- sizeof *used + num * sizeof *used->ring);
+ sizeof *used + num * sizeof *used->ring + s);
}
/* Can we log writes? */
@@ -514,9 +520,11 @@
/* Verify access for write logging. */
/* Caller should have vq mutex and device mutex */
-static int vq_log_access_ok(struct vhost_virtqueue *vq, void __user *log_base)
+static int vq_log_access_ok(struct vhost_dev *d, struct vhost_virtqueue *vq,
+ void __user *log_base)
{
struct vhost_memory *mp;
+ size_t s = vhost_has_feature(d, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
mp = rcu_dereference_protected(vq->dev->memory,
lockdep_is_held(&vq->mutex));
@@ -524,15 +532,15 @@
vhost_has_feature(vq->dev, VHOST_F_LOG_ALL)) &&
(!vq->log_used || log_access_ok(log_base, vq->log_addr,
sizeof *vq->used +
- vq->num * sizeof *vq->used->ring));
+ vq->num * sizeof *vq->used->ring + s));
}
/* Can we start vq? */
/* Caller should have vq mutex and device mutex */
int vhost_vq_access_ok(struct vhost_virtqueue *vq)
{
- return vq_access_ok(vq->num, vq->desc, vq->avail, vq->used) &&
- vq_log_access_ok(vq, vq->log_base);
+ return vq_access_ok(vq->dev, vq->num, vq->desc, vq->avail, vq->used) &&
+ vq_log_access_ok(vq->dev, vq, vq->log_base);
}
static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m)
@@ -577,6 +585,7 @@
if (r)
return r;
+ vq->signalled_used_valid = false;
return get_user(vq->last_used_idx, &used->idx);
}
@@ -674,7 +683,7 @@
* If it is not, we don't as size might not have been setup.
* We will verify when backend is configured. */
if (vq->private_data) {
- if (!vq_access_ok(vq->num,
+ if (!vq_access_ok(d, vq->num,
(void __user *)(unsigned long)a.desc_user_addr,
(void __user *)(unsigned long)a.avail_user_addr,
(void __user *)(unsigned long)a.used_user_addr)) {
@@ -818,7 +827,7 @@
vq = d->vqs + i;
mutex_lock(&vq->mutex);
/* If ring is inactive, will check when it's enabled. */
- if (vq->private_data && !vq_log_access_ok(vq, base))
+ if (vq->private_data && !vq_log_access_ok(d, vq, base))
r = -EFAULT;
else
vq->log_base = base;
@@ -1219,6 +1228,10 @@
/* On success, increment avail index. */
vq->last_avail_idx++;
+
+ /* Assume notifications from guest are disabled at this point,
+ * if they aren't we would need to update avail_event index. */
+ BUG_ON(!(vq->used_flags & VRING_USED_F_NO_NOTIFY));
return head;
}
@@ -1267,6 +1280,12 @@
eventfd_signal(vq->log_ctx, 1);
}
vq->last_used_idx++;
+ /* If the driver never bothers to signal in a very long while,
+ * used index might wrap around. If that happens, invalidate
+ * signalled_used index we stored. TODO: make sure driver
+ * signals at least once in 2^16 and remove this. */
+ if (unlikely(vq->last_used_idx == vq->signalled_used))
+ vq->signalled_used_valid = false;
return 0;
}
@@ -1275,6 +1294,7 @@
unsigned count)
{
struct vring_used_elem __user *used;
+ u16 old, new;
int start;
start = vq->last_used_idx % vq->num;
@@ -1292,7 +1312,14 @@
((void __user *)used - (void __user *)vq->used),
count * sizeof *used);
}
- vq->last_used_idx += count;
+ old = vq->last_used_idx;
+ new = (vq->last_used_idx += count);
+ /* If the driver never bothers to signal in a very long while,
+ * used index might wrap around. If that happens, invalidate
+ * signalled_used index we stored. TODO: make sure driver
+ * signals at least once in 2^16 and remove this. */
+ if (unlikely((u16)(new - vq->signalled_used) < (u16)(new - old)))
+ vq->signalled_used_valid = false;
return 0;
}
@@ -1331,29 +1358,47 @@
return r;
}
-/* This actually signals the guest, using eventfd. */
-void vhost_signal(struct vhost_dev *dev, struct vhost_virtqueue *vq)
+static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
{
- __u16 flags;
-
+ __u16 old, new, event;
+ bool v;
/* Flush out used index updates. This is paired
* with the barrier that the Guest executes when enabling
* interrupts. */
smp_mb();
- if (__get_user(flags, &vq->avail->flags)) {
- vq_err(vq, "Failed to get flags");
- return;
+ if (vhost_has_feature(dev, VIRTIO_F_NOTIFY_ON_EMPTY) &&
+ unlikely(vq->avail_idx == vq->last_avail_idx))
+ return true;
+
+ if (!vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
+ __u16 flags;
+ if (__get_user(flags, &vq->avail->flags)) {
+ vq_err(vq, "Failed to get flags");
+ return true;
+ }
+ return !(flags & VRING_AVAIL_F_NO_INTERRUPT);
}
+ old = vq->signalled_used;
+ v = vq->signalled_used_valid;
+ new = vq->signalled_used = vq->last_used_idx;
+ vq->signalled_used_valid = true;
- /* If they don't want an interrupt, don't signal, unless empty. */
- if ((flags & VRING_AVAIL_F_NO_INTERRUPT) &&
- (vq->avail_idx != vq->last_avail_idx ||
- !vhost_has_feature(dev, VIRTIO_F_NOTIFY_ON_EMPTY)))
- return;
+ if (unlikely(!v))
+ return true;
+ if (get_user(event, vhost_used_event(vq))) {
+ vq_err(vq, "Failed to get used event idx");
+ return true;
+ }
+ return vring_need_event(event, new, old);
+}
+
+/* This actually signals the guest, using eventfd. */
+void vhost_signal(struct vhost_dev *dev, struct vhost_virtqueue *vq)
+{
/* Signal the Guest tell them we used something up. */
- if (vq->call_ctx)
+ if (vq->call_ctx && vhost_notify(dev, vq))
eventfd_signal(vq->call_ctx, 1);
}
@@ -1376,7 +1421,7 @@
}
/* OK, now we need to know about added descriptors. */
-bool vhost_enable_notify(struct vhost_virtqueue *vq)
+bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
{
u16 avail_idx;
int r;
@@ -1384,11 +1429,34 @@
if (!(vq->used_flags & VRING_USED_F_NO_NOTIFY))
return false;
vq->used_flags &= ~VRING_USED_F_NO_NOTIFY;
- r = put_user(vq->used_flags, &vq->used->flags);
- if (r) {
- vq_err(vq, "Failed to enable notification at %p: %d\n",
- &vq->used->flags, r);
- return false;
+ if (!vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
+ r = put_user(vq->used_flags, &vq->used->flags);
+ if (r) {
+ vq_err(vq, "Failed to enable notification at %p: %d\n",
+ &vq->used->flags, r);
+ return false;
+ }
+ } else {
+ r = put_user(vq->avail_idx, vhost_avail_event(vq));
+ if (r) {
+ vq_err(vq, "Failed to update avail event index at %p: %d\n",
+ vhost_avail_event(vq), r);
+ return false;
+ }
+ }
+ if (unlikely(vq->log_used)) {
+ void __user *used;
+ /* Make sure data is seen before log. */
+ smp_wmb();
+ used = vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX) ?
+ &vq->used->flags : vhost_avail_event(vq);
+ /* Log used flags or event index entry write. Both are 16 bit
+ * fields. */
+ log_write(vq->log_base, vq->log_addr +
+ (used - (void __user *)vq->used),
+ sizeof(u16));
+ if (vq->log_ctx)
+ eventfd_signal(vq->log_ctx, 1);
}
/* They could have slipped one in as we were doing that: make
* sure it's written, then check again. */
@@ -1404,15 +1472,17 @@
}
/* We don't need to be notified again. */
-void vhost_disable_notify(struct vhost_virtqueue *vq)
+void vhost_disable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
{
int r;
if (vq->used_flags & VRING_USED_F_NO_NOTIFY)
return;
vq->used_flags |= VRING_USED_F_NO_NOTIFY;
- r = put_user(vq->used_flags, &vq->used->flags);
- if (r)
- vq_err(vq, "Failed to enable notification at %p: %d\n",
- &vq->used->flags, r);
+ if (!vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
+ r = put_user(vq->used_flags, &vq->used->flags);
+ if (r)
+ vq_err(vq, "Failed to enable notification at %p: %d\n",
+ &vq->used->flags, r);
+ }
}
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index b3363ae..8e03379 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -84,6 +84,12 @@
/* Used flags */
u16 used_flags;
+ /* Last used index value we have signalled on */
+ u16 signalled_used;
+
+ /* Last used index value we have signalled on */
+ bool signalled_used_valid;
+
/* Log writes to used structure. */
bool log_used;
u64 log_addr;
@@ -149,8 +155,8 @@
void vhost_add_used_and_signal_n(struct vhost_dev *, struct vhost_virtqueue *,
struct vring_used_elem *heads, unsigned count);
void vhost_signal(struct vhost_dev *, struct vhost_virtqueue *);
-void vhost_disable_notify(struct vhost_virtqueue *);
-bool vhost_enable_notify(struct vhost_virtqueue *);
+void vhost_disable_notify(struct vhost_dev *, struct vhost_virtqueue *);
+bool vhost_enable_notify(struct vhost_dev *, struct vhost_virtqueue *);
int vhost_log_write(struct vhost_virtqueue *vq, struct vhost_log *log,
unsigned int log_num, u64 len);
@@ -162,11 +168,12 @@
} while (0)
enum {
- VHOST_FEATURES = (1 << VIRTIO_F_NOTIFY_ON_EMPTY) |
- (1 << VIRTIO_RING_F_INDIRECT_DESC) |
- (1 << VHOST_F_LOG_ALL) |
- (1 << VHOST_NET_F_VIRTIO_NET_HDR) |
- (1 << VIRTIO_NET_F_MRG_RXBUF),
+ VHOST_FEATURES = (1ULL << VIRTIO_F_NOTIFY_ON_EMPTY) |
+ (1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
+ (1ULL << VIRTIO_RING_F_EVENT_IDX) |
+ (1ULL << VHOST_F_LOG_ALL) |
+ (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)
diff --git a/drivers/virtio/virtio_balloon.c b/drivers/virtio/virtio_balloon.c
index 0f1da45..e058ace 100644
--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -40,9 +40,6 @@
/* Waiting for host to ack the pages we released. */
struct completion acked;
- /* Do we have to tell Host *before* we reuse pages? */
- bool tell_host_first;
-
/* The pages we've told the Host we're not using. */
unsigned int num_pages;
struct list_head pages;
@@ -151,13 +148,14 @@
vb->num_pages--;
}
- if (vb->tell_host_first) {
- tell_host(vb, vb->deflate_vq);
- release_pages_by_pfn(vb->pfns, vb->num_pfns);
- } else {
- release_pages_by_pfn(vb->pfns, vb->num_pfns);
- tell_host(vb, vb->deflate_vq);
- }
+
+ /*
+ * Note that if
+ * virtio_has_feature(vdev, VIRTIO_BALLOON_F_MUST_TELL_HOST);
+ * is true, we *have* to do it in this order
+ */
+ tell_host(vb, vb->deflate_vq);
+ release_pages_by_pfn(vb->pfns, vb->num_pfns);
}
static inline void update_stat(struct virtio_balloon *vb, int idx,
@@ -325,9 +323,6 @@
goto out_del_vqs;
}
- vb->tell_host_first
- = virtio_has_feature(vdev, VIRTIO_BALLOON_F_MUST_TELL_HOST);
-
return 0;
out_del_vqs:
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index b0043fb2..68b91368 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -82,6 +82,9 @@
/* Host supports indirect buffers */
bool indirect;
+ /* Host publishes avail event idx */
+ bool event;
+
/* Number of free buffers */
unsigned int num_free;
/* Head of free buffer list. */
@@ -237,18 +240,22 @@
void virtqueue_kick(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
+ u16 new, old;
START_USE(vq);
/* Descriptors and available array need to be set before we expose the
* new available array entries. */
virtio_wmb();
- vq->vring.avail->idx += vq->num_added;
+ old = vq->vring.avail->idx;
+ new = vq->vring.avail->idx = old + vq->num_added;
vq->num_added = 0;
/* Need to update avail index before checking if we should notify */
virtio_mb();
- if (!(vq->vring.used->flags & VRING_USED_F_NO_NOTIFY))
+ if (vq->event ?
+ vring_need_event(vring_avail_event(&vq->vring), new, old) :
+ !(vq->vring.used->flags & VRING_USED_F_NO_NOTIFY))
/* Prod other side to tell it about changes. */
vq->notify(&vq->vq);
@@ -324,6 +331,14 @@
ret = vq->data[i];
detach_buf(vq, i);
vq->last_used_idx++;
+ /* If we expect an interrupt for the next entry, tell host
+ * by writing event index and flush out the write before
+ * the read in the next get_buf call. */
+ if (!(vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT)) {
+ vring_used_event(&vq->vring) = vq->last_used_idx;
+ virtio_mb();
+ }
+
END_USE(vq);
return ret;
}
@@ -345,7 +360,11 @@
/* We optimistically turn back on interrupts, then check if there was
* more to do. */
+ /* Depending on the VIRTIO_RING_F_EVENT_IDX feature, we need to
+ * either clear the flags bit or point the event index at the next
+ * entry. Always do both to keep code simple. */
vq->vring.avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT;
+ vring_used_event(&vq->vring) = vq->last_used_idx;
virtio_mb();
if (unlikely(more_used(vq))) {
END_USE(vq);
@@ -357,6 +376,33 @@
}
EXPORT_SYMBOL_GPL(virtqueue_enable_cb);
+bool virtqueue_enable_cb_delayed(struct virtqueue *_vq)
+{
+ struct vring_virtqueue *vq = to_vvq(_vq);
+ u16 bufs;
+
+ START_USE(vq);
+
+ /* We optimistically turn back on interrupts, then check if there was
+ * more to do. */
+ /* Depending on the VIRTIO_RING_F_USED_EVENT_IDX feature, we need to
+ * either clear the flags bit or point the event index at the next
+ * entry. Always do both to keep code simple. */
+ vq->vring.avail->flags &= ~VRING_AVAIL_F_NO_INTERRUPT;
+ /* TODO: tune this threshold */
+ bufs = (u16)(vq->vring.avail->idx - vq->last_used_idx) * 3 / 4;
+ vring_used_event(&vq->vring) = vq->last_used_idx + bufs;
+ virtio_mb();
+ if (unlikely((u16)(vq->vring.used->idx - vq->last_used_idx) > bufs)) {
+ END_USE(vq);
+ return false;
+ }
+
+ END_USE(vq);
+ return true;
+}
+EXPORT_SYMBOL_GPL(virtqueue_enable_cb_delayed);
+
void *virtqueue_detach_unused_buf(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
@@ -438,6 +484,7 @@
#endif
vq->indirect = virtio_has_feature(vdev, VIRTIO_RING_F_INDIRECT_DESC);
+ vq->event = virtio_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX);
/* No callback? Tell other side not to bother us. */
if (!callback)
@@ -472,6 +519,8 @@
switch (i) {
case VIRTIO_RING_F_INDIRECT_DESC:
break;
+ case VIRTIO_RING_F_EVENT_IDX:
+ break;
default:
/* We don't understand this bit. */
clear_bit(i, vdev->features);
diff --git a/include/linux/virtio.h b/include/linux/virtio.h
index aff5b4f..7108857 100644
--- a/include/linux/virtio.h
+++ b/include/linux/virtio.h
@@ -51,6 +51,13 @@
* This re-enables callbacks; it returns "false" if there are pending
* buffers in the queue, to detect a possible race between the driver
* checking for more work, and enabling callbacks.
+ * virtqueue_enable_cb_delayed: restart callbacks after disable_cb.
+ * vq: the struct virtqueue we're talking about.
+ * This re-enables callbacks but hints to the other side to delay
+ * interrupts until most of the available buffers have been processed;
+ * it returns "false" if there are many pending buffers in the queue,
+ * to detect a possible race between the driver checking for more work,
+ * and enabling callbacks.
* virtqueue_detach_unused_buf: detach first unused buffer
* vq: the struct virtqueue we're talking about.
* Returns NULL or the "data" token handed to add_buf
@@ -86,6 +93,8 @@
bool virtqueue_enable_cb(struct virtqueue *vq);
+bool virtqueue_enable_cb_delayed(struct virtqueue *vq);
+
void *virtqueue_detach_unused_buf(struct virtqueue *vq);
/**
diff --git a/include/linux/virtio_9p.h b/include/linux/virtio_9p.h
index e68b439b..277c4ad 100644
--- a/include/linux/virtio_9p.h
+++ b/include/linux/virtio_9p.h
@@ -1,7 +1,30 @@
#ifndef _LINUX_VIRTIO_9P_H
#define _LINUX_VIRTIO_9P_H
/* This header is BSD licensed so anyone can use the definitions to implement
- * compatible drivers/servers. */
+ * compatible drivers/servers.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE. */
#include <linux/types.h>
#include <linux/virtio_ids.h>
#include <linux/virtio_config.h>
diff --git a/include/linux/virtio_balloon.h b/include/linux/virtio_balloon.h
index a50ecd1..652dc8b 100644
--- a/include/linux/virtio_balloon.h
+++ b/include/linux/virtio_balloon.h
@@ -1,7 +1,30 @@
#ifndef _LINUX_VIRTIO_BALLOON_H
#define _LINUX_VIRTIO_BALLOON_H
/* This header is BSD licensed so anyone can use the definitions to implement
- * compatible drivers/servers. */
+ * compatible drivers/servers.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE. */
#include <linux/virtio_ids.h>
#include <linux/virtio_config.h>
diff --git a/include/linux/virtio_blk.h b/include/linux/virtio_blk.h
index 167720d..e0edb40 100644
--- a/include/linux/virtio_blk.h
+++ b/include/linux/virtio_blk.h
@@ -1,7 +1,30 @@
#ifndef _LINUX_VIRTIO_BLK_H
#define _LINUX_VIRTIO_BLK_H
/* This header is BSD licensed so anyone can use the definitions to implement
- * compatible drivers/servers. */
+ * compatible drivers/servers.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE. */
#include <linux/types.h>
#include <linux/virtio_ids.h>
#include <linux/virtio_config.h>
diff --git a/include/linux/virtio_config.h b/include/linux/virtio_config.h
index 800617b..39c88c5 100644
--- a/include/linux/virtio_config.h
+++ b/include/linux/virtio_config.h
@@ -1,7 +1,30 @@
#ifndef _LINUX_VIRTIO_CONFIG_H
#define _LINUX_VIRTIO_CONFIG_H
/* This header, excluding the #ifdef __KERNEL__ part, is BSD licensed so
- * anyone can use the definitions to implement compatible drivers/servers. */
+ * anyone can use the definitions to implement compatible drivers/servers.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE. */
/* Virtio devices use a standardized configuration space to define their
* features and pass configuration information, but each implementation can
diff --git a/include/linux/virtio_console.h b/include/linux/virtio_console.h
index e4d3335..bdf4b00 100644
--- a/include/linux/virtio_console.h
+++ b/include/linux/virtio_console.h
@@ -5,7 +5,31 @@
#include <linux/virtio_config.h>
/*
* This header, excluding the #ifdef __KERNEL__ part, is BSD licensed so
- * anyone can use the definitions to implement compatible drivers/servers.
+ * anyone can use the definitions to implement compatible drivers/servers:
+ *
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
*
* Copyright (C) Red Hat, Inc., 2009, 2010, 2011
* Copyright (C) Amit Shah <amit.shah@redhat.com>, 2009, 2010, 2011
diff --git a/include/linux/virtio_ids.h b/include/linux/virtio_ids.h
index 06660c0..85bb0bb 100644
--- a/include/linux/virtio_ids.h
+++ b/include/linux/virtio_ids.h
@@ -5,7 +5,29 @@
*
* This header is BSD licensed so anyone can use the definitions to implement
* compatible drivers/servers.
- */
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE. */
#define VIRTIO_ID_NET 1 /* virtio net */
#define VIRTIO_ID_BLOCK 2 /* virtio block */
diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h
index 085e422..136040b 100644
--- a/include/linux/virtio_net.h
+++ b/include/linux/virtio_net.h
@@ -1,7 +1,30 @@
#ifndef _LINUX_VIRTIO_NET_H
#define _LINUX_VIRTIO_NET_H
/* This header is BSD licensed so anyone can use the definitions to implement
- * compatible drivers/servers. */
+ * compatible drivers/servers.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE. */
#include <linux/types.h>
#include <linux/virtio_ids.h>
#include <linux/virtio_config.h>
diff --git a/include/linux/virtio_pci.h b/include/linux/virtio_pci.h
index 9a3d7c4..ea66f3f 100644
--- a/include/linux/virtio_pci.h
+++ b/include/linux/virtio_pci.h
@@ -11,6 +11,29 @@
*
* This header is BSD licensed so anyone can use the definitions to implement
* compatible drivers/servers.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
*/
#ifndef _LINUX_VIRTIO_PCI_H
diff --git a/include/linux/virtio_ring.h b/include/linux/virtio_ring.h
index e4d144b..4a32cb6 100644
--- a/include/linux/virtio_ring.h
+++ b/include/linux/virtio_ring.h
@@ -7,6 +7,29 @@
* This header is BSD licensed so anyone can use the definitions to implement
* compatible drivers/servers.
*
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
* Copyright Rusty Russell IBM Corporation 2007. */
#include <linux/types.h>
@@ -29,6 +52,12 @@
/* We support indirect buffer descriptors */
#define VIRTIO_RING_F_INDIRECT_DESC 28
+/* The Guest publishes the used index for which it expects an interrupt
+ * at the end of the avail ring. Host should ignore the avail->flags field. */
+/* The Host publishes the avail index for which it expects a kick
+ * at the end of the used ring. Guest should ignore the used->flags field. */
+#define VIRTIO_RING_F_EVENT_IDX 29
+
/* Virtio ring descriptors: 16 bytes. These can chain together via "next". */
struct vring_desc {
/* Address (guest-physical). */
@@ -83,6 +112,7 @@
* __u16 avail_flags;
* __u16 avail_idx;
* __u16 available[num];
+ * __u16 used_event_idx;
*
* // Padding to the next align boundary.
* char pad[];
@@ -91,8 +121,14 @@
* __u16 used_flags;
* __u16 used_idx;
* struct vring_used_elem used[num];
+ * __u16 avail_event_idx;
* };
*/
+/* We publish the used event index at the end of the available ring, and vice
+ * versa. They are at the end for backwards compatibility. */
+#define vring_used_event(vr) ((vr)->avail->ring[(vr)->num])
+#define vring_avail_event(vr) (*(__u16 *)&(vr)->used->ring[(vr)->num])
+
static inline void vring_init(struct vring *vr, unsigned int num, void *p,
unsigned long align)
{
@@ -107,7 +143,21 @@
{
return ((sizeof(struct vring_desc) * num + sizeof(__u16) * (2 + num)
+ align - 1) & ~(align - 1))
- + sizeof(__u16) * 2 + sizeof(struct vring_used_elem) * num;
+ + sizeof(__u16) * 3 + sizeof(struct vring_used_elem) * num;
+}
+
+/* The following is used with USED_EVENT_IDX and AVAIL_EVENT_IDX */
+/* Assuming a given event_idx value from the other size, if
+ * we have just incremented index from old to new_idx,
+ * should we trigger an event? */
+static inline int vring_need_event(__u16 event_idx, __u16 new_idx, __u16 old)
+{
+ /* Note: Xen has similar logic for notification hold-off
+ * in include/xen/interface/io/ring.h with req_event and req_prod
+ * corresponding to event_idx + 1 and new_idx respectively.
+ * Note also that req_event and req_prod in Xen start at 1,
+ * event indexes in virtio start at 0. */
+ return (__u16)(new_idx - event_idx - 1) < (__u16)(new_idx - old);
}
#ifdef __KERNEL__
diff --git a/tools/virtio/virtio_test.c b/tools/virtio/virtio_test.c
index df0c6d2..74d3331 100644
--- a/tools/virtio/virtio_test.c
+++ b/tools/virtio/virtio_test.c
@@ -198,6 +198,14 @@
.val = 'h',
},
{
+ .name = "event-idx",
+ .val = 'E',
+ },
+ {
+ .name = "no-event-idx",
+ .val = 'e',
+ },
+ {
.name = "indirect",
.val = 'I',
},
@@ -211,13 +219,17 @@
static void help()
{
- fprintf(stderr, "Usage: virtio_test [--help] [--no-indirect]\n");
+ fprintf(stderr, "Usage: virtio_test [--help]"
+ " [--no-indirect]"
+ " [--no-event-idx]"
+ "\n");
}
int main(int argc, char **argv)
{
struct vdev_info dev;
- unsigned long long features = 1ULL << VIRTIO_RING_F_INDIRECT_DESC;
+ unsigned long long features = (1ULL << VIRTIO_RING_F_INDIRECT_DESC) |
+ (1ULL << VIRTIO_RING_F_EVENT_IDX);
int o;
for (;;) {
@@ -228,6 +240,9 @@
case '?':
help();
exit(2);
+ case 'e':
+ features &= ~(1ULL << VIRTIO_RING_F_EVENT_IDX);
+ break;
case 'h':
help();
goto done;
