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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:
  lguest: make Launcher see device status updates
  lguest: remove bogus NULL cpu check
  lguest: avoid using NR_CPUS as a bounds check.
  virtio: add virtio disk geometry feature
  virtio: explicit advertisement of driver features
  virtio: change config to guest endian.
  virtio: finer-grained features for virtio_net
  virtio: wean net driver off NETDEV_TX_BUSY
  virtio-blk: fix remove oops
  virtio: fix scatterlist sizing in net driver.
  virtio: de-structify virtio_block status byte
  virtio: export more headers to userspace
  virtio: fix sparse return void-valued expression warnings
  virtio: fix tx_ stats in virtio_net
  virtio: ignore corrupted virtqueues rather than spinning.
This commit is contained in:
Linus Torvalds 2008-05-02 08:20:04 -07:00
parent 8bec4a5d93 a007a751d9
commit 02cdf0827b
14 changed files with 323 additions and 158 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

62
Documentation/lguest/lguest.c
View File

@ -131,6 +131,9 @@ struct device
/* Any queues attached to this device */
struct virtqueue *vq;
/* Handle status being finalized (ie. feature bits stable). */
void (*ready)(struct device *me);
/* Device-specific data. */
void *priv;
};
@ -925,24 +928,40 @@ static void enable_fd(int fd, struct virtqueue *vq)
write(waker_fd, &vq->dev->fd, sizeof(vq->dev->fd));
}
/* When the Guest asks us to reset a device, it's is fairly easy. */
static void reset_device(struct device *dev)
/* When the Guest tells us they updated the status field, we handle it. */
static void update_device_status(struct device *dev)
{
struct virtqueue *vq;
verbose("Resetting device %s\n", dev->name);
/* Clear the status. */
dev->desc->status = 0;
/* This is a reset. */
if (dev->desc->status == 0) {
verbose("Resetting device %s\n", dev->name);
/* Clear any features they've acked. */
memset(get_feature_bits(dev) + dev->desc->feature_len, 0,
dev->desc->feature_len);
/* Clear any features they've acked. */
memset(get_feature_bits(dev) + dev->desc->feature_len, 0,
dev->desc->feature_len);
/* Zero out the virtqueues. */
for (vq = dev->vq; vq; vq = vq->next) {
memset(vq->vring.desc, 0,
vring_size(vq->config.num, getpagesize()));
vq->last_avail_idx = 0;
/* Zero out the virtqueues. */
for (vq = dev->vq; vq; vq = vq->next) {
memset(vq->vring.desc, 0,
vring_size(vq->config.num, getpagesize()));
vq->last_avail_idx = 0;
}
} else if (dev->desc->status & VIRTIO_CONFIG_S_FAILED) {
warnx("Device %s configuration FAILED", dev->name);
} else if (dev->desc->status & VIRTIO_CONFIG_S_DRIVER_OK) {
unsigned int i;
verbose("Device %s OK: offered", dev->name);
for (i = 0; i < dev->desc->feature_len; i++)
verbose(" %08x", get_feature_bits(dev)[i]);
verbose(", accepted");
for (i = 0; i < dev->desc->feature_len; i++)
verbose(" %08x", get_feature_bits(dev)
[dev->desc->feature_len+i]);
if (dev->ready)
dev->ready(dev);
}
}
@ -954,9 +973,9 @@ static void handle_output(int fd, unsigned long addr)
/* Check each device and virtqueue. */
for (i = devices.dev; i; i = i->next) {
/* Notifications to device descriptors reset the device. */
/* Notifications to device descriptors update device status. */
if (from_guest_phys(addr) == i->desc) {
reset_device(i);
update_device_status(i);
return;
}
@ -1170,6 +1189,7 @@ static struct device *new_device(const char *name, u16 type, int fd,
dev->handle_input = handle_input;
dev->name = name;
dev->vq = NULL;
dev->ready = NULL;
/* Append to device list. Prepending to a single-linked list is
* easier, but the user expects the devices to be arranged on the bus
@ -1398,7 +1418,7 @@ static bool service_io(struct device *dev)
struct vblk_info *vblk = dev->priv;
unsigned int head, out_num, in_num, wlen;
int ret;
struct virtio_blk_inhdr *in;
u8 *in;
struct virtio_blk_outhdr *out;
struct iovec iov[dev->vq->vring.num];
off64_t off;
@ -1416,7 +1436,7 @@ static bool service_io(struct device *dev)
head, out_num, in_num);
out = convert(&iov[0], struct virtio_blk_outhdr);
in = convert(&iov[out_num+in_num-1], struct virtio_blk_inhdr);
in = convert(&iov[out_num+in_num-1], u8);
off = out->sector * 512;
/* The block device implements "barriers", where the Guest indicates
@ -1430,7 +1450,7 @@ static bool service_io(struct device *dev)
* It'd be nice if we supported eject, for example, but we don't. */
if (out->type & VIRTIO_BLK_T_SCSI_CMD) {
fprintf(stderr, "Scsi commands unsupported\n");
in->status = VIRTIO_BLK_S_UNSUPP;
*in = VIRTIO_BLK_S_UNSUPP;
wlen = sizeof(*in);
} else if (out->type & VIRTIO_BLK_T_OUT) {
/* Write */
@ -1453,7 +1473,7 @@ static bool service_io(struct device *dev)
errx(1, "Write past end %llu+%u", off, ret);
}
wlen = sizeof(*in);
in->status = (ret >= 0 ? VIRTIO_BLK_S_OK : VIRTIO_BLK_S_IOERR);
*in = (ret >= 0 ? VIRTIO_BLK_S_OK : VIRTIO_BLK_S_IOERR);
} else {
/* Read */
@ -1466,10 +1486,10 @@ static bool service_io(struct device *dev)
verbose("READ from sector %llu: %i\n", out->sector, ret);
if (ret >= 0) {
wlen = sizeof(*in) + ret;
in->status = VIRTIO_BLK_S_OK;
*in = VIRTIO_BLK_S_OK;
} else {
wlen = sizeof(*in);
in->status = VIRTIO_BLK_S_IOERR;
*in = VIRTIO_BLK_S_IOERR;
}
}

44
drivers/block/virtio_blk.c
View File

@ -35,7 +35,7 @@ struct virtblk_req
struct list_head list;
struct request *req;
struct virtio_blk_outhdr out_hdr;
struct virtio_blk_inhdr in_hdr;
u8 status;
};
static void blk_done(struct virtqueue *vq)
@ -48,7 +48,7 @@ static void blk_done(struct virtqueue *vq)
spin_lock_irqsave(&vblk->lock, flags);
while ((vbr = vblk->vq->vq_ops->get_buf(vblk->vq, &len)) != NULL) {
int uptodate;
switch (vbr->in_hdr.status) {
switch (vbr->status) {
case VIRTIO_BLK_S_OK:
uptodate = 1;
break;
@ -101,7 +101,7 @@ static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
sg_init_table(vblk->sg, VIRTIO_MAX_SG);
sg_set_buf(&vblk->sg[0], &vbr->out_hdr, sizeof(vbr->out_hdr));
num = blk_rq_map_sg(q, vbr->req, vblk->sg+1);
sg_set_buf(&vblk->sg[num+1], &vbr->in_hdr, sizeof(vbr->in_hdr));
sg_set_buf(&vblk->sg[num+1], &vbr->status, sizeof(vbr->status));
if (rq_data_dir(vbr->req) == WRITE) {
vbr->out_hdr.type |= VIRTIO_BLK_T_OUT;
@ -157,10 +157,25 @@ static int virtblk_ioctl(struct inode *inode, struct file *filp,
/* We provide getgeo only to please some old bootloader/partitioning tools */
static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo)
{
/* some standard values, similar to sd */
geo->heads = 1 << 6;
geo->sectors = 1 << 5;
geo->cylinders = get_capacity(bd->bd_disk) >> 11;
struct virtio_blk *vblk = bd->bd_disk->private_data;
struct virtio_blk_geometry vgeo;
int err;
/* see if the host passed in geometry config */
err = virtio_config_val(vblk->vdev, VIRTIO_BLK_F_GEOMETRY,
offsetof(struct virtio_blk_config, geometry),
&vgeo);
if (!err) {
geo->heads = vgeo.heads;
geo->sectors = vgeo.sectors;
geo->cylinders = vgeo.cylinders;
} else {
/* some standard values, similar to sd */
geo->heads = 1 << 6;
geo->sectors = 1 << 5;
geo->cylinders = get_capacity(bd->bd_disk) >> 11;
}
return 0;
}
@ -242,12 +257,12 @@ static int virtblk_probe(struct virtio_device *vdev)
index++;
/* If barriers are supported, tell block layer that queue is ordered */
if (vdev->config->feature(vdev, VIRTIO_BLK_F_BARRIER))
if (virtio_has_feature(vdev, VIRTIO_BLK_F_BARRIER))
blk_queue_ordered(vblk->disk->queue, QUEUE_ORDERED_TAG, NULL);
/* Host must always specify the capacity. */
__virtio_config_val(vdev, offsetof(struct virtio_blk_config, capacity),
&cap);
vdev->config->get(vdev, offsetof(struct virtio_blk_config, capacity),
&cap, sizeof(cap));
/* If capacity is too big, truncate with warning. */
if ((sector_t)cap != cap) {
@ -289,7 +304,6 @@ out:
static void virtblk_remove(struct virtio_device *vdev)
{
struct virtio_blk *vblk = vdev->priv;
int major = vblk->disk->major;
/* Nothing should be pending. */
BUG_ON(!list_empty(&vblk->reqs));
@ -299,7 +313,6 @@ static void virtblk_remove(struct virtio_device *vdev)
blk_cleanup_queue(vblk->disk->queue);
put_disk(vblk->disk);
unregister_blkdev(major, "virtblk");
mempool_destroy(vblk->pool);
vdev->config->del_vq(vblk->vq);
kfree(vblk);
@ -310,7 +323,14 @@ static struct virtio_device_id id_table[] = {
{ 0 },
};
static unsigned int features[] = {
VIRTIO_BLK_F_BARRIER, VIRTIO_BLK_F_SEG_MAX, VIRTIO_BLK_F_SIZE_MAX,
VIRTIO_BLK_F_GEOMETRY,
};
static struct virtio_driver virtio_blk = {
.feature_table = features,
.feature_table_size = ARRAY_SIZE(features),
.driver.name = KBUILD_MODNAME,
.driver.owner = THIS_MODULE,
.id_table = id_table,

68
drivers/lguest/lguest_device.c
View File

@ -85,27 +85,34 @@ static unsigned desc_size(const struct lguest_device_desc *desc)
+ desc->config_len;
}
/* This tests (and acknowleges) a feature bit. */
static bool lg_feature(struct virtio_device *vdev, unsigned fbit)
/* This gets the device's feature bits. */
static u32 lg_get_features(struct virtio_device *vdev)
{
unsigned int i;
u32 features = 0;
struct lguest_device_desc *desc = to_lgdev(vdev)->desc;
u8 *features;
u8 *in_features = lg_features(desc);
/* Obviously if they ask for a feature off the end of our feature
* bitmap, it's not set. */
if (fbit / 8 > desc->feature_len)
return false;
/* We do this the slow but generic way. */
for (i = 0; i < min(desc->feature_len * 8, 32); i++)
if (in_features[i / 8] & (1 << (i % 8)))
features |= (1 << i);
/* The feature bitmap comes after the virtqueues. */
features = lg_features(desc);
if (!(features[fbit / 8] & (1 << (fbit % 8))))
return false;
return features;
}
/* We set the matching bit in the other half of the bitmap to tell the
* Host we want to use this feature. We don't use this yet, but we
* could in future. */
features[desc->feature_len + fbit / 8] |= (1 << (fbit % 8));
return true;
static void lg_set_features(struct virtio_device *vdev, u32 features)
{
unsigned int i;
struct lguest_device_desc *desc = to_lgdev(vdev)->desc;
/* Second half of bitmap is features we accept. */
u8 *out_features = lg_features(desc) + desc->feature_len;
memset(out_features, 0, desc->feature_len);
for (i = 0; i < min(desc->feature_len * 8, 32); i++) {
if (features & (1 << i))
out_features[i / 8] |= (1 << (i % 8));
}
}
/* Once they've found a field, getting a copy of it is easy. */
@ -137,22 +144,28 @@ static u8 lg_get_status(struct virtio_device *vdev)
return to_lgdev(vdev)->desc->status;
}
static void lg_set_status(struct virtio_device *vdev, u8 status)
{
BUG_ON(!status);
to_lgdev(vdev)->desc->status = status;
}
/* To reset the device, we (ab)use the NOTIFY hypercall, with the descriptor
* address of the device. The Host will zero the status and all the
* features. */
static void lg_reset(struct virtio_device *vdev)
/* To notify on status updates, we (ab)use the NOTIFY hypercall, with the
* descriptor address of the device. A zero status means "reset". */
static void set_status(struct virtio_device *vdev, u8 status)
{
unsigned long offset = (void *)to_lgdev(vdev)->desc - lguest_devices;
/* We set the status. */
to_lgdev(vdev)->desc->status = status;
hcall(LHCALL_NOTIFY, (max_pfn<<PAGE_SHIFT) + offset, 0, 0);
}
static void lg_set_status(struct virtio_device *vdev, u8 status)
{
BUG_ON(!status);
set_status(vdev, status);
}
static void lg_reset(struct virtio_device *vdev)
{
set_status(vdev, 0);
}
/*
* Virtqueues
*
@ -286,7 +299,8 @@ static void lg_del_vq(struct virtqueue *vq)
/* The ops structure which hooks everything together. */
static struct virtio_config_ops lguest_config_ops = {
.feature = lg_feature,
.get_features = lg_get_features,
.set_features = lg_set_features,
.get = lg_get,
.set = lg_set,
.get_status = lg_get_status,

4
drivers/lguest/lguest_user.c
View File

@ -102,7 +102,7 @@ static ssize_t read(struct file *file, char __user *user, size_t size,loff_t*o)
static int lg_cpu_start(struct lg_cpu *cpu, unsigned id, unsigned long start_ip)
{
/* We have a limited number the number of CPUs in the lguest struct. */
if (id >= NR_CPUS)
if (id >= ARRAY_SIZE(cpu->lg->cpus))
return -EINVAL;
/* Set up this CPU's id, and pointer back to the lguest struct. */
@ -251,8 +251,6 @@ static ssize_t write(struct file *file, const char __user *in,
if (!lg || (cpu_id >= lg->nr_cpus))
return -EINVAL;
cpu = &lg->cpus[cpu_id];
if (!cpu)
return -EINVAL;
/* Once the Guest is dead, you can only read() why it died. */
if (lg->dead)

96
drivers/net/virtio_net.c
View File

@ -41,6 +41,9 @@ struct virtnet_info
struct net_device *dev;
struct napi_struct napi;
/* The skb we couldn't send because buffers were full. */
struct sk_buff *last_xmit_skb;
/* Number of input buffers, and max we've ever had. */
unsigned int num, max;
@ -142,10 +145,10 @@ drop:
static void try_fill_recv(struct virtnet_info *vi)
{
struct sk_buff *skb;
struct scatterlist sg[1+MAX_SKB_FRAGS];
struct scatterlist sg[2+MAX_SKB_FRAGS];
int num, err;
sg_init_table(sg, 1+MAX_SKB_FRAGS);
sg_init_table(sg, 2+MAX_SKB_FRAGS);
for (;;) {
skb = netdev_alloc_skb(vi->dev, MAX_PACKET_LEN);
if (unlikely(!skb))
@ -221,23 +224,22 @@ static void free_old_xmit_skbs(struct virtnet_info *vi)
while ((skb = vi->svq->vq_ops->get_buf(vi->svq, &len)) != NULL) {
pr_debug("Sent skb %p\n", skb);
__skb_unlink(skb, &vi->send);
vi->dev->stats.tx_bytes += len;
vi->dev->stats.tx_bytes += skb->len;
vi->dev->stats.tx_packets++;
kfree_skb(skb);
}
}
static int start_xmit(struct sk_buff *skb, struct net_device *dev)
static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
{
struct virtnet_info *vi = netdev_priv(dev);
int num, err;
struct scatterlist sg[1+MAX_SKB_FRAGS];
int num;
struct scatterlist sg[2+MAX_SKB_FRAGS];
struct virtio_net_hdr *hdr;
const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
sg_init_table(sg, 1+MAX_SKB_FRAGS);
sg_init_table(sg, 2+MAX_SKB_FRAGS);
pr_debug("%s: xmit %p " MAC_FMT "\n", dev->name, skb,
pr_debug("%s: xmit %p " MAC_FMT "\n", vi->dev->name, skb,
dest[0], dest[1], dest[2],
dest[3], dest[4], dest[5]);
@ -272,30 +274,51 @@ static int start_xmit(struct sk_buff *skb, struct net_device *dev)
vnet_hdr_to_sg(sg, skb);
num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
__skb_queue_head(&vi->send, skb);
return vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb);
}
static int start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct virtnet_info *vi = netdev_priv(dev);
again:
/* Free up any pending old buffers before queueing new ones. */
free_old_xmit_skbs(vi);
err = vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb);
if (err) {
pr_debug("%s: virtio not prepared to send\n", dev->name);
netif_stop_queue(dev);
/* Activate callback for using skbs: if this returns false it
* means some were used in the meantime. */
if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
vi->svq->vq_ops->disable_cb(vi->svq);
netif_start_queue(dev);
goto again;
/* If we has a buffer left over from last time, send it now. */
if (vi->last_xmit_skb) {
if (xmit_skb(vi, vi->last_xmit_skb) != 0) {
/* Drop this skb: we only queue one. */
vi->dev->stats.tx_dropped++;
kfree_skb(skb);
goto stop_queue;
}
__skb_unlink(skb, &vi->send);
return NETDEV_TX_BUSY;
vi->last_xmit_skb = NULL;
}
vi->svq->vq_ops->kick(vi->svq);
return 0;
/* Put new one in send queue and do transmit */
__skb_queue_head(&vi->send, skb);
if (xmit_skb(vi, skb) != 0) {
vi->last_xmit_skb = skb;
goto stop_queue;
}
done:
vi->svq->vq_ops->kick(vi->svq);
return NETDEV_TX_OK;
stop_queue:
pr_debug("%s: virtio not prepared to send\n", dev->name);
netif_stop_queue(dev);
/* Activate callback for using skbs: if this returns false it
* means some were used in the meantime. */
if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
vi->svq->vq_ops->disable_cb(vi->svq);
netif_start_queue(dev);
goto again;
}
goto done;
}
#ifdef CONFIG_NET_POLL_CONTROLLER
@ -355,17 +378,26 @@ static int virtnet_probe(struct virtio_device *vdev)
SET_NETDEV_DEV(dev, &vdev->dev);
/* Do we support "hardware" checksums? */
if (csum && vdev->config->feature(vdev, VIRTIO_NET_F_CSUM)) {
if (csum && virtio_has_feature(vdev, VIRTIO_NET_F_CSUM)) {
/* This opens up the world of extra features. */
dev->features |= NETIF_F_HW_CSUM|NETIF_F_SG|NETIF_F_FRAGLIST;
if (gso && vdev->config->feature(vdev, VIRTIO_NET_F_GSO)) {
if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_GSO)) {
dev->features |= NETIF_F_TSO | NETIF_F_UFO
| NETIF_F_TSO_ECN | NETIF_F_TSO6;
}
/* Individual feature bits: what can host handle? */
if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO4))
dev->features |= NETIF_F_TSO;
if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_TSO6))
dev->features |= NETIF_F_TSO6;
if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_ECN))
dev->features |= NETIF_F_TSO_ECN;
if (gso && virtio_has_feature(vdev, VIRTIO_NET_F_HOST_UFO))
dev->features |= NETIF_F_UFO;
}
/* Configuration may specify what MAC to use. Otherwise random. */
if (vdev->config->feature(vdev, VIRTIO_NET_F_MAC)) {
if (virtio_has_feature(vdev, VIRTIO_NET_F_MAC)) {
vdev->config->get(vdev,
offsetof(struct virtio_net_config, mac),
dev->dev_addr, dev->addr_len);
@ -454,7 +486,15 @@ static struct virtio_device_id id_table[] = {
{ 0 },
};
static unsigned int features[] = {
VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
VIRTIO_NET_F_HOST_ECN,
};
static struct virtio_driver virtio_net = {
.feature_table = features,
.feature_table_size = ARRAY_SIZE(features),
.driver.name = KBUILD_MODNAME,
.driver.owner = THIS_MODULE,
.id_table = id_table,

38
drivers/virtio/virtio.c
View File

@ -80,19 +80,51 @@ static void add_status(struct virtio_device *dev, unsigned status)
dev->config->set_status(dev, dev->config->get_status(dev) | status);
}
void virtio_check_driver_offered_feature(const struct virtio_device *vdev,
unsigned int fbit)
{
unsigned int i;
struct virtio_driver *drv = container_of(vdev->dev.driver,
struct virtio_driver, driver);
for (i = 0; i < drv->feature_table_size; i++)
if (drv->feature_table[i] == fbit)
return;
BUG();
}
EXPORT_SYMBOL_GPL(virtio_check_driver_offered_feature);
static int virtio_dev_probe(struct device *_d)
{
int err;
int err, i;
struct virtio_device *dev = container_of(_d,struct virtio_device,dev);
struct virtio_driver *drv = container_of(dev->dev.driver,
struct virtio_driver, driver);
u32 device_features;
/* We have a driver! */
add_status(dev, VIRTIO_CONFIG_S_DRIVER);
/* Figure out what features the device supports. */
device_features = dev->config->get_features(dev);
/* Features supported by both device and driver into dev->features. */
memset(dev->features, 0, sizeof(dev->features));
for (i = 0; i < drv->feature_table_size; i++) {
unsigned int f = drv->feature_table[i];
BUG_ON(f >= 32);
if (device_features & (1 << f))
set_bit(f, dev->features);
}
err = drv->probe(dev);
if (err)
add_status(dev, VIRTIO_CONFIG_S_FAILED);
else
else {
add_status(dev, VIRTIO_CONFIG_S_DRIVER_OK);
/* They should never have set feature bits beyond 32 */
dev->config->set_features(dev, dev->features[0]);
}
return err;
}
@ -114,6 +146,8 @@ static int virtio_dev_remove(struct device *_d)
int register_virtio_driver(struct virtio_driver *driver)
{
/* Catch this early. */
BUG_ON(driver->feature_table_size && !driver->feature_table);
driver->driver.bus = &virtio_bus;
driver->driver.probe = virtio_dev_probe;
driver->driver.remove = virtio_dev_remove;

12
drivers/virtio/virtio_balloon.c
View File

@ -155,9 +155,9 @@ static void virtballoon_changed(struct virtio_device *vdev)
static inline s64 towards_target(struct virtio_balloon *vb)
{
u32 v;
__virtio_config_val(vb->vdev,
offsetof(struct virtio_balloon_config, num_pages),
&v);
vb->vdev->config->get(vb->vdev,
offsetof(struct virtio_balloon_config, num_pages),
&v, sizeof(v));
return v - vb->num_pages;
}
@ -227,7 +227,7 @@ static int virtballoon_probe(struct virtio_device *vdev)
}
vb->tell_host_first
= vdev->config->feature(vdev, VIRTIO_BALLOON_F_MUST_TELL_HOST);
= virtio_has_feature(vdev, VIRTIO_BALLOON_F_MUST_TELL_HOST);
return 0;
@ -259,7 +259,11 @@ static void virtballoon_remove(struct virtio_device *vdev)
kfree(vb);
}
static unsigned int features[] = { VIRTIO_BALLOON_F_MUST_TELL_HOST };
static struct virtio_driver virtio_balloon = {
.feature_table = features,
.feature_table_size = ARRAY_SIZE(features),
.driver.name = KBUILD_MODNAME,
.driver.owner = THIS_MODULE,
.id_table = id_table,

32
drivers/virtio/virtio_pci.c
View File

@ -87,23 +87,22 @@ static struct virtio_pci_device *to_vp_device(struct virtio_device *vdev)
return container_of(vdev, struct virtio_pci_device, vdev);
}
/* virtio config->feature() implementation */
static bool vp_feature(struct virtio_device *vdev, unsigned bit)
/* virtio config->get_features() implementation */
static u32 vp_get_features(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
u32 mask;
/* Since this function is supposed to have the side effect of
* enabling a queried feature, we simulate that by doing a read
* from the host feature bitmask and then writing to the guest
* feature bitmask */
mask = ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES);
if (mask & (1 << bit)) {
mask |= (1 << bit);
iowrite32(mask, vp_dev->ioaddr + VIRTIO_PCI_GUEST_FEATURES);
}
/* When someone needs more than 32 feature bits, we'll need to
* steal a bit to indicate that the rest are somewhere else. */
return ioread32(vp_dev->ioaddr + VIRTIO_PCI_HOST_FEATURES);
}
return !!(mask & (1 << bit));
/* virtio config->set_features() implementation */
static void vp_set_features(struct virtio_device *vdev, u32 features)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
iowrite32(features, vp_dev->ioaddr + VIRTIO_PCI_GUEST_FEATURES);
}
/* virtio config->get() implementation */
@ -145,14 +144,14 @@ static void vp_set_status(struct virtio_device *vdev, u8 status)
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
/* We should never be setting status to 0. */
BUG_ON(status == 0);
return iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
iowrite8(status, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
}
static void vp_reset(struct virtio_device *vdev)
{
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
/* 0 status means a reset. */
return iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
iowrite8(0, vp_dev->ioaddr + VIRTIO_PCI_STATUS);
}
/* the notify function used when creating a virt queue */
@ -293,7 +292,6 @@ static void vp_del_vq(struct virtqueue *vq)
}
static struct virtio_config_ops virtio_pci_config_ops = {
.feature = vp_feature,
.get = vp_get,
.set = vp_set,
.get_status = vp_get_status,
@ -301,6 +299,8 @@ static struct virtio_config_ops virtio_pci_config_ops = {
.reset = vp_reset,
.find_vq = vp_find_vq,
.del_vq = vp_del_vq,
.get_features = vp_get_features,
.set_features = vp_set_features,
};
/* the PCI probing function */

5
drivers/virtio/virtio_ring.c
View File

@ -184,6 +184,11 @@ static void *vring_get_buf(struct virtqueue *_vq, unsigned int *len)
START_USE(vq);
if (unlikely(vq->broken)) {
END_USE(vq);
return NULL;
}
if (!more_used(vq)) {
pr_debug("No more buffers in queue\n");
END_USE(vq);

5
include/linux/Kbuild
View File

@ -346,6 +346,11 @@ unifdef-y += videodev.h
unifdef-y += virtio_config.h
unifdef-y += virtio_blk.h
unifdef-y += virtio_net.h
unifdef-y += virtio_9p.h
unifdef-y += virtio_balloon.h
unifdef-y += virtio_console.h
unifdef-y += virtio_pci.h
unifdef-y += virtio_ring.h
unifdef-y += vt.h
unifdef-y += wait.h
unifdef-y += wanrouter.h

7
include/linux/virtio.h
View File

@ -76,6 +76,7 @@ struct virtqueue_ops {
* @dev: underlying device.
* @id: the device type identification (used to match it with a driver).
* @config: the configuration ops for this device.
* @features: the features supported by both driver and device.
* @priv: private pointer for the driver's use.
*/
struct virtio_device
@ -84,6 +85,8 @@ struct virtio_device
struct device dev;
struct virtio_device_id id;
struct virtio_config_ops *config;
/* Note that this is a Linux set_bit-style bitmap. */
unsigned long features[1];
void *priv;
};
@ -94,6 +97,8 @@ void unregister_virtio_device(struct virtio_device *dev);
* virtio_driver - operations for a virtio I/O driver
* @driver: underlying device driver (populate name and owner).
* @id_table: the ids serviced by this driver.
* @feature_table: an array of feature numbers supported by this device.
* @feature_table_size: number of entries in the feature table array.
* @probe: the function to call when a device is found. Returns a token for
* remove, or PTR_ERR().
* @remove: the function when a device is removed.
@ -103,6 +108,8 @@ void unregister_virtio_device(struct virtio_device *dev);
struct virtio_driver {
struct device_driver driver;
const struct virtio_device_id *id_table;
const unsigned int *feature_table;
unsigned int feature_table_size;
int (*probe)(struct virtio_device *dev);
void (*remove)(struct virtio_device *dev);
void (*config_changed)(struct virtio_device *dev);

14
include/linux/virtio_blk.h
View File

@ -9,6 +9,7 @@
#define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */
#define VIRTIO_BLK_F_SIZE_MAX 1 /* Indicates maximum segment size */
#define VIRTIO_BLK_F_SEG_MAX 2 /* Indicates maximum # of segments */
#define VIRTIO_BLK_F_GEOMETRY 4 /* Legacy geometry available */
struct virtio_blk_config
{
@ -18,6 +19,12 @@ struct virtio_blk_config
__le32 size_max;
/* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */
__le32 seg_max;
/* geometry the device (if VIRTIO_BLK_F_GEOMETRY) */
struct virtio_blk_geometry {
__le16 cylinders;
__u8 heads;
__u8 sectors;
} geometry;
} __attribute__((packed));
/* These two define direction. */
@ -41,13 +48,8 @@ struct virtio_blk_outhdr
__u64 sector;
};
/* And this is the final byte of the write scatter-gather list. */
#define VIRTIO_BLK_S_OK 0
#define VIRTIO_BLK_S_IOERR 1
#define VIRTIO_BLK_S_UNSUPP 2
/* This is the first element of the write scatter-gather list */
struct virtio_blk_inhdr
{
unsigned char status;
};
#endif /* _LINUX_VIRTIO_BLK_H */

81
include/linux/virtio_config.h
View File

@ -16,27 +16,20 @@
#define VIRTIO_CONFIG_S_FAILED 0x80
#ifdef __KERNEL__
struct virtio_device;
#include <linux/virtio.h>
/**
* virtio_config_ops - operations for configuring a virtio device
* @feature: search for a feature in this config
* vdev: the virtio_device
* bit: the feature bit
* Returns true if the feature is supported. Acknowledges the feature
* so the host can see it.
* @get: read the value of a configuration field
* vdev: the virtio_device
* offset: the offset of the configuration field
* buf: the buffer to write the field value into.
* len: the length of the buffer
* Note that contents are conventionally little-endian.
* @set: write the value of a configuration field
* vdev: the virtio_device
* offset: the offset of the configuration field
* buf: the buffer to read the field value from.
* len: the length of the buffer
* Note that contents are conventionally little-endian.
* @get_status: read the status byte
* vdev: the virtio_device
* Returns the status byte
@ -52,10 +45,15 @@ struct virtio_device;
* callback: the virqtueue callback
* Returns the new virtqueue or ERR_PTR() (eg. -ENOENT).
* @del_vq: free a virtqueue found by find_vq().
* @get_features: get the array of feature bits for this device.
* vdev: the virtio_device
* Returns the first 32 feature bits (all we currently need).
* @set_features: confirm what device features we'll be using.
* vdev: the virtio_device
* feature: the first 32 feature bits
*/
struct virtio_config_ops
{
bool (*feature)(struct virtio_device *vdev, unsigned bit);
void (*get)(struct virtio_device *vdev, unsigned offset,
void *buf, unsigned len);
void (*set)(struct virtio_device *vdev, unsigned offset,
@ -67,43 +65,52 @@ struct virtio_config_ops
unsigned index,
void (*callback)(struct virtqueue *));
void (*del_vq)(struct virtqueue *vq);
u32 (*get_features)(struct virtio_device *vdev);
void (*set_features)(struct virtio_device *vdev, u32 features);
};
/* If driver didn't advertise the feature, it will never appear. */
void virtio_check_driver_offered_feature(const struct virtio_device *vdev,
unsigned int fbit);
/**
* virtio_config_val - look for a feature and get a single virtio config.
* virtio_has_feature - helper to determine if this device has this feature.
* @vdev: the device
* @fbit: the feature bit
*/
static inline bool virtio_has_feature(const struct virtio_device *vdev,
unsigned int fbit)
{
/* Did you forget to fix assumptions on max features? */
if (__builtin_constant_p(fbit))
BUILD_BUG_ON(fbit >= 32);
virtio_check_driver_offered_feature(vdev, fbit);
return test_bit(fbit, vdev->features);
}
/**
* virtio_config_val - look for a feature and get a virtio config entry.
* @vdev: the virtio device
* @fbit: the feature bit
* @offset: the type to search for.
* @val: a pointer to the value to fill in.
*
* The return value is -ENOENT if the feature doesn't exist. Otherwise
* the value is endian-corrected and returned in v. */
#define virtio_config_val(vdev, fbit, offset, v) ({ \
int _err; \
if ((vdev)->config->feature((vdev), (fbit))) { \
__virtio_config_val((vdev), (offset), (v)); \
_err = 0; \
} else \
_err = -ENOENT; \
_err; \
})
* the config value is copied into whatever is pointed to by v. */
#define virtio_config_val(vdev, fbit, offset, v) \
virtio_config_buf((vdev), (fbit), (offset), (v), sizeof(v))
/**
* __virtio_config_val - get a single virtio config without feature check.
* @vdev: the virtio device
* @offset: the type to search for.
* @val: a pointer to the value to fill in.
*
* The value is endian-corrected and returned in v. */
#define __virtio_config_val(vdev, offset, v) do { \
BUILD_BUG_ON(sizeof(*(v)) != 1 && sizeof(*(v)) != 2 \
&& sizeof(*(v)) != 4 && sizeof(*(v)) != 8); \
(vdev)->config->get((vdev), (offset), (v), sizeof(*(v))); \
switch (sizeof(*(v))) { \
case 2: le16_to_cpus((__u16 *) v); break; \
case 4: le32_to_cpus((__u32 *) v); break; \
case 8: le64_to_cpus((__u64 *) v); break; \
} \
} while(0)
static inline int virtio_config_buf(struct virtio_device *vdev,
unsigned int fbit,
unsigned int offset,
void *buf, unsigned len)
{
if (!virtio_has_feature(vdev, fbit))
return -ENOENT;
vdev->config->get(vdev, offset, buf, len);
return 0;
}
#endif /* __KERNEL__ */
#endif /* _LINUX_VIRTIO_CONFIG_H */

13
include/linux/virtio_net.h
View File

@ -6,9 +6,18 @@
#define VIRTIO_ID_NET 1
/* The feature bitmap for virtio net */
#define VIRTIO_NET_F_CSUM 0 /* Can handle pkts w/ partial csum */
#define VIRTIO_NET_F_CSUM 0 /* Host handles pkts w/ partial csum */
#define VIRTIO_NET_F_GUEST_CSUM 1 /* Guest handles pkts w/ partial csum */
#define VIRTIO_NET_F_MAC 5 /* Host has given MAC address. */
#define VIRTIO_NET_F_GSO 6 /* Can handle pkts w/ any GSO type */
#define VIRTIO_NET_F_GSO 6 /* Host handles pkts w/ any GSO type */
#define VIRTIO_NET_F_GUEST_TSO4 7 /* Guest can handle TSOv4 in. */
#define VIRTIO_NET_F_GUEST_TSO6 8 /* Guest can handle TSOv6 in. */
#define VIRTIO_NET_F_GUEST_ECN 9 /* Guest can handle TSO[6] w/ ECN in. */
#define VIRTIO_NET_F_GUEST_UFO 10 /* Guest can handle UFO in. */
#define VIRTIO_NET_F_HOST_TSO4 11 /* Host can handle TSOv4 in. */
#define VIRTIO_NET_F_HOST_TSO6 12 /* Host can handle TSOv6 in. */
#define VIRTIO_NET_F_HOST_ECN 13 /* Host can handle TSO[6] w/ ECN in. */
#define VIRTIO_NET_F_HOST_UFO 14 /* Host can handle UFO in. */
struct virtio_net_config
{