* git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus: (25 commits)
virtio: balloon driver
virtio: Use PCI revision field to indicate virtio PCI ABI version
virtio: PCI device
virtio_blk: implement naming for vda-vdz,vdaa-vdzz,vdaaa-vdzzz
virtio_blk: Dont waste major numbers
virtio_blk: provide getgeo
virtio_net: parametrize the napi_weight for virtio receive queue.
virtio: free transmit skbs when notified, not on next xmit.
virtio: flush buffers on open
virtnet: remove double ether_setup
virtio: Allow virtio to be modular and used by modules
virtio: Use the sg_phys convenience function.
virtio: Put the virtio under the virtualization menu
virtio: handle interrupts after callbacks turned off
virtio: reset function
virtio: populate network rings in the probe routine, not open
virtio: Tweak virtio_net defines
virtio: Net header needs hdr_len
virtio: remove unused id field from struct virtio_blk_outhdr
virtio: clarify NO_NOTIFY flag usage
...
#include <zlib.h>
#include <assert.h>
#include <sched.h>
+#include <limits.h>
+#include <stddef.h>
#include "linux/lguest_launcher.h"
#include "linux/virtio_config.h"
#include "linux/virtio_net.h"
/* The descriptor page for the devices. */
u8 *descpage;
- /* The tail of the last descriptor. */
- unsigned int desc_used;
-
/* A single linked list of devices. */
struct device *dev;
- /* ... And an end pointer so we can easily append new devices */
- struct device **lastdev;
+ /* And a pointer to the last device for easy append and also for
+ * configuration appending. */
+ struct device *lastdev;
};
/* The list of Guest devices, based on command line arguments. */
#define cpu_to_le64(v64) (v64)
#define le16_to_cpu(v16) (v16)
#define le32_to_cpu(v32) (v32)
-#define le64_to_cpu(v32) (v64)
+#define le64_to_cpu(v64) (v64)
+
+/* The device virtqueue descriptors are followed by feature bitmasks. */
+static u8 *get_feature_bits(struct device *dev)
+{
+ return (u8 *)(dev->desc + 1)
+ + dev->desc->num_vq * sizeof(struct lguest_vqconfig);
+}
/*L:100 The Launcher code itself takes us out into userspace, that scary place
* where pointers run wild and free! Unfortunately, like most userspace
write(waker_fd, &vq->dev->fd, sizeof(vq->dev->fd));
}
+/* Resetting a device is fairly easy. */
+static void reset_device(struct device *dev)
+{
+ struct virtqueue *vq;
+
+ verbose("Resetting device %s\n", dev->name);
+ /* Clear the status. */
+ dev->desc->status = 0;
+
+ /* 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;
+ }
+}
+
/* This is the generic routine we call when the Guest uses LHCALL_NOTIFY. */
static void handle_output(int fd, unsigned long addr)
{
struct device *i;
struct virtqueue *vq;
- /* Check each virtqueue. */
+ /* Check each device and virtqueue. */
for (i = devices.dev; i; i = i->next) {
+ /* Notifications to device descriptors reset the device. */
+ if (from_guest_phys(addr) == i->desc) {
+ reset_device(i);
+ return;
+ }
+
+ /* Notifications to virtqueues mean output has occurred. */
for (vq = i->vq; vq; vq = vq->next) {
- if (vq->config.pfn == addr/getpagesize()
- && vq->handle_output) {
- verbose("Output to %s\n", vq->dev->name);
- vq->handle_output(fd, vq);
+ if (vq->config.pfn != addr/getpagesize())
+ continue;
+
+ /* Guest should acknowledge (and set features!) before
+ * using the device. */
+ if (i->desc->status == 0) {
+ warnx("%s gave early output", i->name);
return;
}
+
+ if (strcmp(vq->dev->name, "console") != 0)
+ verbose("Output to %s\n", vq->dev->name);
+ if (vq->handle_output)
+ vq->handle_output(fd, vq);
+ return;
}
}
*
* All devices need a descriptor so the Guest knows it exists, and a "struct
* device" so the Launcher can keep track of it. We have common helper
- * routines to allocate them.
- *
- * This routine allocates a new "struct lguest_device_desc" from descriptor
- * table just above the Guest's normal memory. It returns a pointer to that
- * descriptor. */
-static struct lguest_device_desc *new_dev_desc(u16 type)
-{
- struct lguest_device_desc *d;
+ * routines to allocate and manage them. */
- /* We only have one page for all the descriptors. */
- if (devices.desc_used + sizeof(*d) > getpagesize())
- errx(1, "Too many devices");
-
- /* We don't need to set config_len or status: page is 0 already. */
- d = (void *)devices.descpage + devices.desc_used;
- d->type = type;
- devices.desc_used += sizeof(*d);
-
- return d;
+/* The layout of the device page is a "struct lguest_device_desc" followed by a
+ * number of virtqueue descriptors, then two sets of feature bits, then an
+ * array of configuration bytes. This routine returns the configuration
+ * pointer. */
+static u8 *device_config(const struct device *dev)
+{
+ return (void *)(dev->desc + 1)
+ + dev->desc->num_vq * sizeof(struct lguest_vqconfig)
+ + dev->desc->feature_len * 2;
}
-/* Each device descriptor is followed by some configuration information.
- * Each configuration field looks like: u8 type, u8 len, [... len bytes...].
- *
- * This routine adds a new field to an existing device's descriptor. It only
- * works for the last device, but that's OK because that's how we use it. */
-static void add_desc_field(struct device *dev, u8 type, u8 len, const void *c)
+/* This routine allocates a new "struct lguest_device_desc" from descriptor
+ * table page just above the Guest's normal memory. It returns a pointer to
+ * that descriptor. */
+static struct lguest_device_desc *new_dev_desc(u16 type)
{
- /* This is the last descriptor, right? */
- assert(devices.descpage + devices.desc_used
- == (u8 *)(dev->desc + 1) + dev->desc->config_len);
+ struct lguest_device_desc d = { .type = type };
+ void *p;
- /* We only have one page of device descriptions. */
- if (devices.desc_used + 2 + len > getpagesize())
- errx(1, "Too many devices");
+ /* Figure out where the next device config is, based on the last one. */
+ if (devices.lastdev)
+ p = device_config(devices.lastdev)
+ + devices.lastdev->desc->config_len;
+ else
+ p = devices.descpage;
- /* Copy in the new config header: type then length. */
- devices.descpage[devices.desc_used++] = type;
- devices.descpage[devices.desc_used++] = len;
- memcpy(devices.descpage + devices.desc_used, c, len);
- devices.desc_used += len;
+ /* We only have one page for all the descriptors. */
+ if (p + sizeof(d) > (void *)devices.descpage + getpagesize())
+ errx(1, "Too many devices");
- /* Update the device descriptor length: two byte head then data. */
- dev->desc->config_len += 2 + len;
+ /* p might not be aligned, so we memcpy in. */
+ return memcpy(p, &d, sizeof(d));
}
-/* This routine adds a virtqueue to a device. We specify how many descriptors
- * the virtqueue is to have. */
+/* Each device descriptor is followed by the description of its virtqueues. We
+ * specify how many descriptors the virtqueue is to have. */
static void add_virtqueue(struct device *dev, unsigned int num_descs,
void (*handle_output)(int fd, struct virtqueue *me))
{
/* Initialize the vring. */
vring_init(&vq->vring, num_descs, p, getpagesize());
- /* Add the configuration information to this device's descriptor. */
- add_desc_field(dev, VIRTIO_CONFIG_F_VIRTQUEUE,
- sizeof(vq->config), &vq->config);
+ /* Append virtqueue to this device's descriptor. We use
+ * device_config() to get the end of the device's current virtqueues;
+ * we check that we haven't added any config or feature information
+ * yet, otherwise we'd be overwriting them. */
+ assert(dev->desc->config_len == 0 && dev->desc->feature_len == 0);
+ memcpy(device_config(dev), &vq->config, sizeof(vq->config));
+ dev->desc->num_vq++;
+
+ verbose("Virtqueue page %#lx\n", to_guest_phys(p));
/* Add to tail of list, so dev->vq is first vq, dev->vq->next is
* second. */
* virtqueue. */
vq->handle_output = handle_output;
- /* Set the "Don't Notify Me" flag if we don't have a handler */
+ /* As an optimization, set the advisory "Don't Notify Me" flag if we
+ * don't have a handler */
if (!handle_output)
vq->vring.used->flags = VRING_USED_F_NO_NOTIFY;
}
+/* The first half of the feature bitmask is for us to advertise features. The
+ * second half if for the Guest to accept features. */
+static void add_feature(struct device *dev, unsigned bit)
+{
+ u8 *features = get_feature_bits(dev);
+
+ /* We can't extend the feature bits once we've added config bytes */
+ if (dev->desc->feature_len <= bit / CHAR_BIT) {
+ assert(dev->desc->config_len == 0);
+ dev->desc->feature_len = (bit / CHAR_BIT) + 1;
+ }
+
+ features[bit / CHAR_BIT] |= (1 << (bit % CHAR_BIT));
+}
+
+/* This routine sets the configuration fields for an existing device's
+ * descriptor. It only works for the last device, but that's OK because that's
+ * how we use it. */
+static void set_config(struct device *dev, unsigned len, const void *conf)
+{
+ /* Check we haven't overflowed our single page. */
+ if (device_config(dev) + len > devices.descpage + getpagesize())
+ errx(1, "Too many devices");
+
+ /* Copy in the config information, and store the length. */
+ memcpy(device_config(dev), conf, len);
+ dev->desc->config_len = len;
+}
+
/* This routine does all the creation and setup of a new device, including
* calling new_dev_desc() to allocate the descriptor and device memory. */
static struct device *new_device(const char *name, u16 type, int fd,
{
struct device *dev = malloc(sizeof(*dev));
- /* Append to device list. Prepending to a single-linked list is
- * easier, but the user expects the devices to be arranged on the bus
- * in command-line order. The first network device on the command line
- * is eth0, the first block device /dev/vda, etc. */
- *devices.lastdev = dev;
- dev->next = NULL;
- devices.lastdev = &dev->next;
-
/* Now we populate the fields one at a time. */
dev->fd = fd;
/* If we have an input handler for this file descriptor, then we add it
dev->handle_input = handle_input;
dev->name = name;
dev->vq = 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
+ * in command-line order. The first network device on the command line
+ * is eth0, the first block device /dev/vda, etc. */
+ if (devices.lastdev)
+ devices.lastdev->next = dev;
+ else
+ devices.dev = dev;
+ devices.lastdev = dev;
+
return dev;
}
int netfd, ipfd;
u32 ip;
const char *br_name = NULL;
- u8 hwaddr[6];
+ struct virtio_net_config conf;
/* We open the /dev/net/tun device and tell it we want a tap device. A
* tap device is like a tun device, only somehow different. To tell
ip = str2ip(arg);
/* Set up the tun device, and get the mac address for the interface. */
- configure_device(ipfd, ifr.ifr_name, ip, hwaddr);
+ configure_device(ipfd, ifr.ifr_name, ip, conf.mac);
/* Tell Guest what MAC address to use. */
- add_desc_field(dev, VIRTIO_CONFIG_NET_MAC_F, sizeof(hwaddr), hwaddr);
+ add_feature(dev, VIRTIO_NET_F_MAC);
+ set_config(dev, sizeof(conf), &conf);
- /* We don't seed the socket any more; setup is done. */
+ /* We don't need the socket any more; setup is done. */
close(ipfd);
verbose("device %u: tun net %u.%u.%u.%u\n",
struct device *dev;
struct vblk_info *vblk;
void *stack;
- u64 cap;
- unsigned int val;
+ struct virtio_blk_config conf;
/* This is the pipe the I/O thread will use to tell us I/O is done. */
pipe(p);
vblk->fd = open_or_die(filename, O_RDWR|O_LARGEFILE);
vblk->len = lseek64(vblk->fd, 0, SEEK_END);
+ /* We support barriers. */
+ add_feature(dev, VIRTIO_BLK_F_BARRIER);
+
/* Tell Guest how many sectors this device has. */
- cap = cpu_to_le64(vblk->len / 512);
- add_desc_field(dev, VIRTIO_CONFIG_BLK_F_CAPACITY, sizeof(cap), &cap);
+ conf.capacity = cpu_to_le64(vblk->len / 512);
/* Tell Guest not to put in too many descriptors at once: two are used
* for the in and out elements. */
- val = cpu_to_le32(VIRTQUEUE_NUM - 2);
- add_desc_field(dev, VIRTIO_CONFIG_BLK_F_SEG_MAX, sizeof(val), &val);
+ add_feature(dev, VIRTIO_BLK_F_SEG_MAX);
+ conf.seg_max = cpu_to_le32(VIRTQUEUE_NUM - 2);
+
+ set_config(dev, sizeof(conf), &conf);
/* The I/O thread writes to this end of the pipe when done. */
vblk->done_fd = p[1];
close(vblk->workpipe[0]);
verbose("device %u: virtblock %llu sectors\n",
- devices.device_num, cap);
+ devices.device_num, le64_to_cpu(conf.capacity));
}
/* That's the end of device setup. :*/
/* First we initialize the device list. Since console and network
* device receive input from a file descriptor, we keep an fdset
* (infds) and the maximum fd number (max_infd) with the head of the
- * list. We also keep a pointer to the last device, for easy appending
- * to the list. Finally, we keep the next interrupt number to hand out
- * (1: remember that 0 is used by the timer). */
+ * list. We also keep a pointer to the last device. Finally, we keep
+ * the next interrupt number to hand out (1: remember that 0 is used by
+ * the timer). */
FD_ZERO(&devices.infds);
devices.max_infd = -1;
- devices.lastdev = &devices.dev;
+ devices.lastdev = NULL;
devices.next_irq = 1;
cpu_id = 0;
# OK, it's a little counter-intuitive to do this, but it puts it neatly under
# the virtualization menu.
source drivers/lguest/Kconfig
+source drivers/virtio/Kconfig
endif # VIRTUALIZATION
source "drivers/auxdisplay/Kconfig"
source "drivers/uio/Kconfig"
-
-source "drivers/virtio/Kconfig"
endmenu
tristate "Virtio block driver (EXPERIMENTAL)"
depends on EXPERIMENTAL && VIRTIO
---help---
- This is the virtual block driver for lguest. Say Y or M.
+ This is the virtual block driver for virtio. It can be used with
+ lguest or QEMU based VMMs (like KVM or Xen). Say Y or M.
endif # BLK_DEV
#include <linux/scatterlist.h>
#define VIRTIO_MAX_SG (3+MAX_PHYS_SEGMENTS)
+#define PART_BITS 4
+
+static int major, index;
-static unsigned char virtblk_index = 'a';
struct virtio_blk
{
spinlock_t lock;
struct virtio_blk_inhdr in_hdr;
};
-static bool blk_done(struct virtqueue *vq)
+static void blk_done(struct virtqueue *vq)
{
struct virtio_blk *vblk = vq->vdev->priv;
struct virtblk_req *vbr;
/* In case queue is stopped waiting for more buffers. */
blk_start_queue(vblk->disk->queue);
spin_unlock_irqrestore(&vblk->lock, flags);
- return true;
}
static bool do_req(struct request_queue *q, struct virtio_blk *vblk,
(void __user *)data);
}
+/* 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;
+ return 0;
+}
+
static struct block_device_operations virtblk_fops = {
- .ioctl = virtblk_ioctl,
- .owner = THIS_MODULE,
+ .ioctl = virtblk_ioctl,
+ .owner = THIS_MODULE,
+ .getgeo = virtblk_getgeo,
};
+static int index_to_minor(int index)
+{
+ return index << PART_BITS;
+}
+
static int virtblk_probe(struct virtio_device *vdev)
{
struct virtio_blk *vblk;
- int err, major;
- void *token;
- unsigned int len;
+ int err;
u64 cap;
u32 v;
+ if (index_to_minor(index) >= 1 << MINORBITS)
+ return -ENOSPC;
+
vdev->priv = vblk = kmalloc(sizeof(*vblk), GFP_KERNEL);
if (!vblk) {
err = -ENOMEM;
vblk->vdev = vdev;
/* We expect one virtqueue, for output. */
- vblk->vq = vdev->config->find_vq(vdev, blk_done);
+ vblk->vq = vdev->config->find_vq(vdev, 0, blk_done);
if (IS_ERR(vblk->vq)) {
err = PTR_ERR(vblk->vq);
goto out_free_vblk;
goto out_free_vq;
}
- major = register_blkdev(0, "virtblk");
- if (major < 0) {
- err = major;
- goto out_mempool;
- }
-
/* FIXME: How many partitions? How long is a piece of string? */
- vblk->disk = alloc_disk(1 << 4);
+ vblk->disk = alloc_disk(1 << PART_BITS);
if (!vblk->disk) {
err = -ENOMEM;
- goto out_unregister_blkdev;
+ goto out_mempool;
}
vblk->disk->queue = blk_init_queue(do_virtblk_request, &vblk->lock);
goto out_put_disk;
}
- sprintf(vblk->disk->disk_name, "vd%c", virtblk_index++);
+ if (index < 26) {
+ sprintf(vblk->disk->disk_name, "vd%c", 'a' + index % 26);
+ } else if (index < (26 + 1) * 26) {
+ sprintf(vblk->disk->disk_name, "vd%c%c",
+ 'a' + index / 26 - 1, 'a' + index % 26);
+ } else {
+ const unsigned int m1 = (index / 26 - 1) / 26 - 1;
+ const unsigned int m2 = (index / 26 - 1) % 26;
+ const unsigned int m3 = index % 26;
+ sprintf(vblk->disk->disk_name, "vd%c%c%c",
+ 'a' + m1, 'a' + m2, 'a' + m3);
+ }
+
vblk->disk->major = major;
- vblk->disk->first_minor = 0;
+ vblk->disk->first_minor = index_to_minor(index);
vblk->disk->private_data = vblk;
vblk->disk->fops = &virtblk_fops;
+ index++;
/* If barriers are supported, tell block layer that queue is ordered */
- token = vdev->config->find(vdev, VIRTIO_CONFIG_BLK_F, &len);
- if (virtio_use_bit(vdev, token, len, VIRTIO_BLK_F_BARRIER))
+ if (vdev->config->feature(vdev, VIRTIO_BLK_F_BARRIER))
blk_queue_ordered(vblk->disk->queue, QUEUE_ORDERED_TAG, NULL);
- err = virtio_config_val(vdev, VIRTIO_CONFIG_BLK_F_CAPACITY, &cap);
- if (err) {
- dev_err(&vdev->dev, "Bad/missing capacity in config\n");
- goto out_cleanup_queue;
- }
+ /* Host must always specify the capacity. */
+ __virtio_config_val(vdev, offsetof(struct virtio_blk_config, capacity),
+ &cap);
/* If capacity is too big, truncate with warning. */
if ((sector_t)cap != cap) {
}
set_capacity(vblk->disk, cap);
- err = virtio_config_val(vdev, VIRTIO_CONFIG_BLK_F_SIZE_MAX, &v);
+ /* Host can optionally specify maximum segment size and number of
+ * segments. */
+ err = virtio_config_val(vdev, VIRTIO_BLK_F_SIZE_MAX,
+ offsetof(struct virtio_blk_config, size_max),
+ &v);
if (!err)
blk_queue_max_segment_size(vblk->disk->queue, v);
- else if (err != -ENOENT) {
- dev_err(&vdev->dev, "Bad SIZE_MAX in config\n");
- goto out_cleanup_queue;
- }
- err = virtio_config_val(vdev, VIRTIO_CONFIG_BLK_F_SEG_MAX, &v);
+ err = virtio_config_val(vdev, VIRTIO_BLK_F_SEG_MAX,
+ offsetof(struct virtio_blk_config, seg_max),
+ &v);
if (!err)
blk_queue_max_hw_segments(vblk->disk->queue, v);
- else if (err != -ENOENT) {
- dev_err(&vdev->dev, "Bad SEG_MAX in config\n");
- goto out_cleanup_queue;
- }
add_disk(vblk->disk);
return 0;
-out_cleanup_queue:
- blk_cleanup_queue(vblk->disk->queue);
out_put_disk:
put_disk(vblk->disk);
-out_unregister_blkdev:
- unregister_blkdev(major, "virtblk");
out_mempool:
mempool_destroy(vblk->pool);
out_free_vq:
struct virtio_blk *vblk = vdev->priv;
int major = vblk->disk->major;
+ /* Nothing should be pending. */
BUG_ON(!list_empty(&vblk->reqs));
+
+ /* Stop all the virtqueues. */
+ vdev->config->reset(vdev);
+
blk_cleanup_queue(vblk->disk->queue);
put_disk(vblk->disk);
unregister_blkdev(major, "virtblk");
mempool_destroy(vblk->pool);
- /* There should be nothing in the queue now, so no need to shutdown */
vdev->config->del_vq(vblk->vq);
kfree(vblk);
}
static int __init init(void)
{
+ major = register_blkdev(0, "virtblk");
+ if (major < 0)
+ return major;
return register_virtio_driver(&virtio_blk);
}
static void __exit fini(void)
{
+ unregister_blkdev(major, "virtblk");
unregister_virtio_driver(&virtio_blk);
}
module_init(init);
/* Find the input queue. */
/* FIXME: This is why we want to wean off hvc: we do nothing
* when input comes in. */
- in_vq = vdev->config->find_vq(vdev, NULL);
+ in_vq = vdev->config->find_vq(vdev, 0, NULL);
if (IS_ERR(in_vq)) {
err = PTR_ERR(in_vq);
goto free;
}
- out_vq = vdev->config->find_vq(vdev, NULL);
+ out_vq = vdev->config->find_vq(vdev, 1, NULL);
if (IS_ERR(out_vq)) {
err = PTR_ERR(out_vq);
goto free_in_vq;
/*D:130
* Device configurations
*
- * The configuration information for a device consists of a series of fields.
- * We don't really care what they are: the Launcher set them up, and the driver
- * will look at them during setup.
+ * The configuration information for a device consists of one or more
+ * virtqueues, a feature bitmaks, and some configuration bytes. The
+ * configuration bytes don't really matter to us: the Launcher sets them up, and
+ * the driver will look at them during setup.
*
- * For us these fields come immediately after that device's descriptor in the
- * lguest_devices page.
- *
- * Each field starts with a "type" byte, a "length" byte, then that number of
- * bytes of configuration information. The device descriptor tells us the
- * total configuration length so we know when we've reached the last field. */
+ * A convenient routine to return the device's virtqueue config array:
+ * immediately after the descriptor. */
+static struct lguest_vqconfig *lg_vq(const struct lguest_device_desc *desc)
+{
+ return (void *)(desc + 1);
+}
-/* type + length bytes */
-#define FHDR_LEN 2
+/* The features come immediately after the virtqueues. */
+static u8 *lg_features(const struct lguest_device_desc *desc)
+{
+ return (void *)(lg_vq(desc) + desc->num_vq);
+}
-/* This finds the first field of a given type for a device's configuration. */
-static void *lg_find(struct virtio_device *vdev, u8 type, unsigned int *len)
+/* The config space comes after the two feature bitmasks. */
+static u8 *lg_config(const struct lguest_device_desc *desc)
{
- struct lguest_device_desc *desc = to_lgdev(vdev)->desc;
- int i;
-
- for (i = 0; i < desc->config_len; i += FHDR_LEN + desc->config[i+1]) {
- if (desc->config[i] == type) {
- /* Mark it used, so Host can know we looked at it, and
- * also so we won't find the same one twice. */
- desc->config[i] |= 0x80;
- /* Remember, the second byte is the length. */
- *len = desc->config[i+1];
- /* We return a pointer to the field header. */
- return desc->config + i;
- }
- }
+ return lg_features(desc) + desc->feature_len * 2;
+}
- /* Not found: return NULL for failure. */
- return NULL;
+/* The total size of the config page used by this device (incl. desc) */
+static unsigned desc_size(const struct lguest_device_desc *desc)
+{
+ return sizeof(*desc)
+ + desc->num_vq * sizeof(struct lguest_vqconfig)
+ + desc->feature_len * 2
+ + desc->config_len;
+}
+
+/* This tests (and acknowleges) a feature bit. */
+static bool lg_feature(struct virtio_device *vdev, unsigned fbit)
+{
+ struct lguest_device_desc *desc = to_lgdev(vdev)->desc;
+ u8 *features;
+
+ /* 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;
+
+ /* The feature bitmap comes after the virtqueues. */
+ features = lg_features(desc);
+ if (!(features[fbit / 8] & (1 << (fbit % 8))))
+ return false;
+
+ /* 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;
}
/* Once they've found a field, getting a copy of it is easy. */
-static void lg_get(struct virtio_device *vdev, void *token,
+static void lg_get(struct virtio_device *vdev, unsigned int offset,
void *buf, unsigned len)
{
- /* Check they didn't ask for more than the length of the field! */
- BUG_ON(len > ((u8 *)token)[1]);
- memcpy(buf, token + FHDR_LEN, len);
+ struct lguest_device_desc *desc = to_lgdev(vdev)->desc;
+
+ /* Check they didn't ask for more than the length of the config! */
+ BUG_ON(offset + len > desc->config_len);
+ memcpy(buf, lg_config(desc) + offset, len);
}
/* Setting the contents is also trivial. */
-static void lg_set(struct virtio_device *vdev, void *token,
+static void lg_set(struct virtio_device *vdev, unsigned int offset,
const void *buf, unsigned len)
{
- BUG_ON(len > ((u8 *)token)[1]);
- memcpy(token + FHDR_LEN, buf, len);
+ struct lguest_device_desc *desc = to_lgdev(vdev)->desc;
+
+ /* Check they didn't ask for more than the length of the config! */
+ BUG_ON(offset + len > desc->config_len);
+ memcpy(lg_config(desc) + offset, buf, len);
}
/* The operations to get and set the status word just access the status field
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)
+{
+ unsigned long offset = (void *)to_lgdev(vdev)->desc - lguest_devices;
+
+ hcall(LHCALL_NOTIFY, (max_pfn<<PAGE_SHIFT) + offset, 0, 0);
+}
+
/*
* Virtqueues
*
*
* So we provide devices with a "find virtqueue and set it up" function. */
static struct virtqueue *lg_find_vq(struct virtio_device *vdev,
- bool (*callback)(struct virtqueue *vq))
+ unsigned index,
+ void (*callback)(struct virtqueue *vq))
{
+ struct lguest_device *ldev = to_lgdev(vdev);
struct lguest_vq_info *lvq;
struct virtqueue *vq;
- unsigned int len;
- void *token;
int err;
- /* Look for a field of the correct type to mark a virtqueue. Note that
- * if this succeeds, then the type will be changed so it won't be found
- * again, and future lg_find_vq() calls will find the next
- * virtqueue (if any). */
- token = vdev->config->find(vdev, VIRTIO_CONFIG_F_VIRTQUEUE, &len);
- if (!token)
+ /* We must have this many virtqueues. */
+ if (index >= ldev->desc->num_vq)
return ERR_PTR(-ENOENT);
lvq = kmalloc(sizeof(*lvq), GFP_KERNEL);
if (!lvq)
return ERR_PTR(-ENOMEM);
- /* Note: we could use a configuration space inside here, just like we
- * do for the device. This would allow expansion in future, because
- * our configuration system is designed to be expansible. But this is
- * way easier. */
- if (len != sizeof(lvq->config)) {
- dev_err(&vdev->dev, "Unexpected virtio config len %u\n", len);
- err = -EIO;
- goto free_lvq;
- }
- /* Make a copy of the "struct lguest_vqconfig" field. We need a copy
- * because the config space might not be aligned correctly. */
- vdev->config->get(vdev, token, &lvq->config, sizeof(lvq->config));
+ /* Make a copy of the "struct lguest_vqconfig" entry, which sits after
+ * the descriptor. We need a copy because the config space might not
+ * be aligned correctly. */
+ memcpy(&lvq->config, lg_vq(ldev->desc)+index, sizeof(lvq->config));
+ printk("Mapping virtqueue %i addr %lx\n", index,
+ (unsigned long)lvq->config.pfn << PAGE_SHIFT);
/* Figure out how many pages the ring will take, and map that memory */
lvq->pages = lguest_map((unsigned long)lvq->config.pfn << PAGE_SHIFT,
DIV_ROUND_UP(vring_size(lvq->config.num,
/* The ops structure which hooks everything together. */
static struct virtio_config_ops lguest_config_ops = {
- .find = lg_find,
+ .feature = lg_feature,
.get = lg_get,
.set = lg_set,
.get_status = lg_get_status,
.set_status = lg_set_status,
+ .reset = lg_reset,
.find_vq = lg_find_vq,
.del_vq = lg_del_vq,
};
struct lguest_device_desc *d;
/* We start at the page beginning, and skip over each entry. */
- for (i = 0; i < PAGE_SIZE; i += sizeof(*d) + d->config_len) {
+ for (i = 0; i < PAGE_SIZE; i += desc_size(d)) {
d = lguest_devices + i;
/* Once we hit a zero, stop. */
if (d->type == 0)
break;
+ printk("Device at %i has size %u\n", i, desc_size(d));
add_lguest_device(d);
}
}
tristate "Virtio network driver (EXPERIMENTAL)"
depends on EXPERIMENTAL && VIRTIO
---help---
- This is the virtual network driver for lguest. Say Y or M.
+ This is the virtual network driver for virtio. It can be used with
+ lguest or QEMU based VMMs (like KVM or Xen). Say Y or M.
endif # NETDEVICES
#include <linux/virtio_net.h>
#include <linux/scatterlist.h>
+static int napi_weight = 128;
+module_param(napi_weight, int, 0444);
+
+static int csum = 1, gso = 1;
+module_param(csum, bool, 0444);
+module_param(gso, bool, 0444);
+
/* FIXME: MTU in config. */
#define MAX_PACKET_LEN (ETH_HLEN+ETH_DATA_LEN)
sg_init_one(sg, skb_vnet_hdr(skb), sizeof(struct virtio_net_hdr));
}
-static bool skb_xmit_done(struct virtqueue *rvq)
+static void skb_xmit_done(struct virtqueue *svq)
{
- struct virtnet_info *vi = rvq->vdev->priv;
+ struct virtnet_info *vi = svq->vdev->priv;
- /* In case we were waiting for output buffers. */
+ /* Suppress further interrupts. */
+ svq->vq_ops->disable_cb(svq);
+ /* We were waiting for more output buffers. */
netif_wake_queue(vi->dev);
- return true;
}
static void receive_skb(struct net_device *dev, struct sk_buff *skb,
if (hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
pr_debug("Needs csum!\n");
- skb->ip_summed = CHECKSUM_PARTIAL;
- skb->csum_start = hdr->csum_start;
- skb->csum_offset = hdr->csum_offset;
- if (skb->csum_start > skb->len - 2
- || skb->csum_offset > skb->len - 2) {
- if (net_ratelimit())
- printk(KERN_WARNING "%s: csum=%u/%u len=%u\n",
- dev->name, skb->csum_start,
- skb->csum_offset, skb->len);
+ if (!skb_partial_csum_set(skb,hdr->csum_start,hdr->csum_offset))
goto frame_err;
- }
}
if (hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
pr_debug("GSO!\n");
- switch (hdr->gso_type) {
+ switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
case VIRTIO_NET_HDR_GSO_TCPV4:
skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4;
break;
- case VIRTIO_NET_HDR_GSO_TCPV4_ECN:
- skb_shinfo(skb)->gso_type = SKB_GSO_TCP_ECN;
- break;
case VIRTIO_NET_HDR_GSO_UDP:
skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
break;
goto frame_err;
}
+ if (hdr->gso_type & VIRTIO_NET_HDR_GSO_ECN)
+ skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN;
+
skb_shinfo(skb)->gso_size = hdr->gso_size;
if (skb_shinfo(skb)->gso_size == 0) {
if (net_ratelimit())
vi->rvq->vq_ops->kick(vi->rvq);
}
-static bool skb_recv_done(struct virtqueue *rvq)
+static void skb_recv_done(struct virtqueue *rvq)
{
struct virtnet_info *vi = rvq->vdev->priv;
- netif_rx_schedule(vi->dev, &vi->napi);
- /* Suppress further interrupts. */
- return false;
+ /* Schedule NAPI, Suppress further interrupts if successful. */
+ if (netif_rx_schedule_prep(vi->dev, &vi->napi)) {
+ rvq->vq_ops->disable_cb(rvq);
+ __netif_rx_schedule(vi->dev, &vi->napi);
+ }
}
static int virtnet_poll(struct napi_struct *napi, int budget)
/* Out of packets? */
if (received < budget) {
netif_rx_complete(vi->dev, napi);
- if (unlikely(!vi->rvq->vq_ops->restart(vi->rvq))
+ if (unlikely(!vi->rvq->vq_ops->enable_cb(vi->rvq))
&& netif_rx_reschedule(vi->dev, napi))
goto again;
}
pr_debug("%s: xmit %p %s\n", dev->name, skb, print_mac(mac, dest));
- free_old_xmit_skbs(vi);
-
/* Encode metadata header at front. */
hdr = skb_vnet_hdr(skb);
if (skb->ip_summed == CHECKSUM_PARTIAL) {
}
if (skb_is_gso(skb)) {
+ hdr->hdr_len = skb_transport_header(skb) - skb->data;
hdr->gso_size = skb_shinfo(skb)->gso_size;
- if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
- hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4_ECN;
- else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
+ if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4)
hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
else if (skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6)
hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP;
else
BUG();
+ if (skb_shinfo(skb)->gso_type & SKB_GSO_TCP_ECN)
+ hdr->gso_type |= VIRTIO_NET_HDR_GSO_ECN;
} else {
hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE;
- hdr->gso_size = 0;
+ hdr->gso_size = hdr->hdr_len = 0;
}
vnet_hdr_to_sg(sg, skb);
num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
__skb_queue_head(&vi->send, skb);
+
+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);
- skb_unlink(skb, &vi->send);
netif_stop_queue(dev);
+
+ /* Activate callback for using skbs: if this fails it
+ * means some were used in the meantime. */
+ if (unlikely(!vi->svq->vq_ops->enable_cb(vi->svq))) {
+ printk("Unlikely: restart svq failed\n");
+ netif_start_queue(dev);
+ goto again;
+ }
+ __skb_unlink(skb, &vi->send);
+
return NETDEV_TX_BUSY;
}
vi->svq->vq_ops->kick(vi->svq);
{
struct virtnet_info *vi = netdev_priv(dev);
- try_fill_recv(vi);
+ napi_enable(&vi->napi);
- /* If we didn't even get one input buffer, we're useless. */
- if (vi->num == 0)
- return -ENOMEM;
+ /* If all buffers were filled by other side before we napi_enabled, we
+ * won't get another interrupt, so process any outstanding packets
+ * now. virtnet_poll wants re-enable the queue, so we disable here. */
+ vi->rvq->vq_ops->disable_cb(vi->rvq);
+ netif_rx_schedule(vi->dev, &vi->napi);
- napi_enable(&vi->napi);
return 0;
}
static int virtnet_close(struct net_device *dev)
{
struct virtnet_info *vi = netdev_priv(dev);
- struct sk_buff *skb;
napi_disable(&vi->napi);
- /* networking core has neutered skb_xmit_done/skb_recv_done, so don't
- * worry about races vs. get(). */
- vi->rvq->vq_ops->shutdown(vi->rvq);
- while ((skb = __skb_dequeue(&vi->recv)) != NULL) {
- kfree_skb(skb);
- vi->num--;
- }
- vi->svq->vq_ops->shutdown(vi->svq);
- while ((skb = __skb_dequeue(&vi->send)) != NULL)
- kfree_skb(skb);
-
- BUG_ON(vi->num != 0);
return 0;
}
static int virtnet_probe(struct virtio_device *vdev)
{
int err;
- unsigned int len;
struct net_device *dev;
struct virtnet_info *vi;
- void *token;
/* Allocate ourselves a network device with room for our info */
dev = alloc_etherdev(sizeof(struct virtnet_info));
return -ENOMEM;
/* Set up network device as normal. */
- ether_setup(dev);
dev->open = virtnet_open;
dev->stop = virtnet_close;
dev->hard_start_xmit = start_xmit;
SET_NETDEV_DEV(dev, &vdev->dev);
/* Do we support "hardware" checksums? */
- token = vdev->config->find(vdev, VIRTIO_CONFIG_NET_F, &len);
- if (virtio_use_bit(vdev, token, len, VIRTIO_NET_F_NO_CSUM)) {
+ if (csum && vdev->config->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 (virtio_use_bit(vdev, token, len, VIRTIO_NET_F_TSO4))
- dev->features |= NETIF_F_TSO;
- if (virtio_use_bit(vdev, token, len, VIRTIO_NET_F_UFO))
- dev->features |= NETIF_F_UFO;
- if (virtio_use_bit(vdev, token, len, VIRTIO_NET_F_TSO4_ECN))
- dev->features |= NETIF_F_TSO_ECN;
- if (virtio_use_bit(vdev, token, len, VIRTIO_NET_F_TSO6))
- dev->features |= NETIF_F_TSO6;
+ if (gso && vdev->config->feature(vdev, VIRTIO_NET_F_GSO)) {
+ dev->features |= NETIF_F_TSO | NETIF_F_UFO
+ | NETIF_F_TSO_ECN | NETIF_F_TSO6;
+ }
}
/* Configuration may specify what MAC to use. Otherwise random. */
- token = vdev->config->find(vdev, VIRTIO_CONFIG_NET_MAC_F, &len);
- if (token) {
- dev->addr_len = len;
- vdev->config->get(vdev, token, dev->dev_addr, len);
+ if (vdev->config->feature(vdev, VIRTIO_NET_F_MAC)) {
+ vdev->config->get(vdev,
+ offsetof(struct virtio_net_config, mac),
+ dev->dev_addr, dev->addr_len);
} else
random_ether_addr(dev->dev_addr);
/* Set up our device-specific information */
vi = netdev_priv(dev);
- netif_napi_add(dev, &vi->napi, virtnet_poll, 16);
+ netif_napi_add(dev, &vi->napi, virtnet_poll, napi_weight);
vi->dev = dev;
vi->vdev = vdev;
/* We expect two virtqueues, receive then send. */
- vi->rvq = vdev->config->find_vq(vdev, skb_recv_done);
+ vi->rvq = vdev->config->find_vq(vdev, 0, skb_recv_done);
if (IS_ERR(vi->rvq)) {
err = PTR_ERR(vi->rvq);
goto free;
}
- vi->svq = vdev->config->find_vq(vdev, skb_xmit_done);
+ vi->svq = vdev->config->find_vq(vdev, 1, skb_xmit_done);
if (IS_ERR(vi->svq)) {
err = PTR_ERR(vi->svq);
goto free_recv;
pr_debug("virtio_net: registering device failed\n");
goto free_send;
}
+
+ /* Last of all, set up some receive buffers. */
+ try_fill_recv(vi);
+
+ /* If we didn't even get one input buffer, we're useless. */
+ if (vi->num == 0) {
+ err = -ENOMEM;
+ goto unregister;
+ }
+
pr_debug("virtnet: registered device %s\n", dev->name);
vdev->priv = vi;
return 0;
+unregister:
+ unregister_netdev(dev);
free_send:
vdev->config->del_vq(vi->svq);
free_recv:
static void virtnet_remove(struct virtio_device *vdev)
{
struct virtnet_info *vi = vdev->priv;
+ struct sk_buff *skb;
+
+ /* Stop all the virtqueues. */
+ vdev->config->reset(vdev);
+
+ /* Free our skbs in send and recv queues, if any. */
+ while ((skb = __skb_dequeue(&vi->recv)) != NULL) {
+ kfree_skb(skb);
+ vi->num--;
+ }
+ while ((skb = __skb_dequeue(&vi->send)) != NULL)
+ kfree_skb(skb);
+
+ BUG_ON(vi->num != 0);
vdev->config->del_vq(vi->svq);
vdev->config->del_vq(vi->rvq);
# Virtio always gets selected by whoever wants it.
config VIRTIO
- bool
+ tristate
# Similarly the virtio ring implementation.
config VIRTIO_RING
- bool
+ tristate
depends on VIRTIO
+
+config VIRTIO_PCI
+ tristate "PCI driver for virtio devices (EXPERIMENTAL)"
+ depends on PCI && EXPERIMENTAL
+ select VIRTIO
+ select VIRTIO_RING
+ ---help---
+ This drivers provides support for virtio based paravirtual device
+ drivers over PCI. This requires that your VMM has appropriate PCI
+ virtio backends. Most QEMU based VMMs should support these devices
+ (like KVM or Xen).
+
+ Currently, the ABI is not considered stable so there is no guarantee
+ that this version of the driver will work with your VMM.
+
+ If unsure, say M.
+
+config VIRTIO_BALLOON
+ tristate "Virtio balloon driver (EXPERIMENTAL)"
+ select VIRTIO
+ select VIRTIO_RING
+ ---help---
+ This driver supports increasing and decreasing the amount
+ of memory within a KVM guest.
+
+ If unsure, say M.
+
obj-$(CONFIG_VIRTIO) += virtio.o
obj-$(CONFIG_VIRTIO_RING) += virtio_ring.o
+obj-$(CONFIG_VIRTIO_PCI) += virtio_pci.o
+obj-$(CONFIG_VIRTIO_BALLOON) += virtio_balloon.o
struct virtio_driver *drv = container_of(dev->dev.driver,
struct virtio_driver, driver);
- dev->config->set_status(dev, dev->config->get_status(dev)
- & ~VIRTIO_CONFIG_S_DRIVER);
drv->remove(dev);
+
+ /* Driver should have reset device. */
+ BUG_ON(dev->config->get_status(dev));
+
+ /* Acknowledge the device's existence again. */
+ add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
return 0;
}
dev->dev.bus = &virtio_bus;
sprintf(dev->dev.bus_id, "%u", dev->index);
+ /* We always start by resetting the device, in case a previous
+ * driver messed it up. This also tests that code path a little. */
+ dev->config->reset(dev);
+
/* Acknowledge that we've seen the device. */
add_status(dev, VIRTIO_CONFIG_S_ACKNOWLEDGE);
}
EXPORT_SYMBOL_GPL(unregister_virtio_device);
-int __virtio_config_val(struct virtio_device *vdev,
- u8 type, void *val, size_t size)
-{
- void *token;
- unsigned int len;
-
- token = vdev->config->find(vdev, type, &len);
- if (!token)
- return -ENOENT;
-
- if (len != size)
- return -EIO;
-
- vdev->config->get(vdev, token, val, size);
- return 0;
-}
-EXPORT_SYMBOL_GPL(__virtio_config_val);
-
-int virtio_use_bit(struct virtio_device *vdev,
- void *token, unsigned int len, unsigned int bitnum)
-{
- unsigned long bits[16];
-
- /* This makes it convenient to pass-through find() results. */
- if (!token)
- return 0;
-
- /* bit not in range of this bitfield? */
- if (bitnum * 8 >= len / 2)
- return 0;
-
- /* Giant feature bitfields are silly. */
- BUG_ON(len > sizeof(bits));
- vdev->config->get(vdev, token, bits, len);
-
- if (!test_bit(bitnum, bits))
- return 0;
-
- /* Set acknowledge bit, and write it back. */
- set_bit(bitnum + len * 8 / 2, bits);
- vdev->config->set(vdev, token, bits, len);
- return 1;
-}
-EXPORT_SYMBOL_GPL(virtio_use_bit);
-
static int virtio_init(void)
{
if (bus_register(&virtio_bus) != 0)
panic("virtio bus registration failed");
return 0;
}
+
+static void __exit virtio_exit(void)
+{
+ bus_unregister(&virtio_bus);
+}
core_initcall(virtio_init);
+module_exit(virtio_exit);
+
+MODULE_LICENSE("GPL");
--- /dev/null
+/* Virtio balloon implementation, inspired by Dor Loar and Marcelo
+ * Tosatti's implementations.
+ *
+ * Copyright 2008 Rusty Russell IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+//#define DEBUG
+#include <linux/virtio.h>
+#include <linux/virtio_balloon.h>
+#include <linux/swap.h>
+#include <linux/kthread.h>
+#include <linux/freezer.h>
+
+struct virtio_balloon
+{
+ struct virtio_device *vdev;
+ struct virtqueue *inflate_vq, *deflate_vq;
+
+ /* Where the ballooning thread waits for config to change. */
+ wait_queue_head_t config_change;
+
+ /* The thread servicing the balloon. */
+ struct task_struct *thread;
+
+ /* 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;
+
+ /* The array of pfns we tell the Host about. */
+ unsigned int num_pfns;
+ u32 pfns[256];
+};
+
+static struct virtio_device_id id_table[] = {
+ { VIRTIO_ID_BALLOON, VIRTIO_DEV_ANY_ID },
+ { 0 },
+};
+
+static void balloon_ack(struct virtqueue *vq)
+{
+ struct virtio_balloon *vb;
+ unsigned int len;
+
+ vb = vq->vq_ops->get_buf(vq, &len);
+ if (vb)
+ complete(&vb->acked);
+}
+
+static void tell_host(struct virtio_balloon *vb, struct virtqueue *vq)
+{
+ struct scatterlist sg;
+
+ sg_init_one(&sg, vb->pfns, sizeof(vb->pfns[0]) * vb->num_pfns);
+
+ init_completion(&vb->acked);
+
+ /* We should always be able to add one buffer to an empty queue. */
+ if (vq->vq_ops->add_buf(vq, &sg, 1, 0, vb) != 0)
+ BUG();
+ vq->vq_ops->kick(vq);
+
+ /* When host has read buffer, this completes via balloon_ack */
+ wait_for_completion(&vb->acked);
+}
+
+static void fill_balloon(struct virtio_balloon *vb, size_t num)
+{
+ /* We can only do one array worth at a time. */
+ num = min(num, ARRAY_SIZE(vb->pfns));
+
+ for (vb->num_pfns = 0; vb->num_pfns < num; vb->num_pfns++) {
+ struct page *page = alloc_page(GFP_HIGHUSER | __GFP_NORETRY);
+ if (!page) {
+ if (printk_ratelimit())
+ dev_printk(KERN_INFO, &vb->vdev->dev,
+ "Out of puff! Can't get %zu pages\n",
+ num);
+ /* Sleep for at least 1/5 of a second before retry. */
+ msleep(200);
+ break;
+ }
+ vb->pfns[vb->num_pfns] = page_to_pfn(page);
+ totalram_pages--;
+ vb->num_pages++;
+ list_add(&page->lru, &vb->pages);
+ }
+
+ /* Didn't get any? Oh well. */
+ if (vb->num_pfns == 0)
+ return;
+
+ tell_host(vb, vb->inflate_vq);
+}
+
+static void release_pages_by_pfn(const u32 pfns[], unsigned int num)
+{
+ unsigned int i;
+
+ for (i = 0; i < num; i++) {
+ __free_page(pfn_to_page(pfns[i]));
+ totalram_pages++;
+ }
+}
+
+static void leak_balloon(struct virtio_balloon *vb, size_t num)
+{
+ struct page *page;
+
+ /* We can only do one array worth at a time. */
+ num = min(num, ARRAY_SIZE(vb->pfns));
+
+ for (vb->num_pfns = 0; vb->num_pfns < num; vb->num_pfns++) {
+ page = list_first_entry(&vb->pages, struct page, lru);
+ list_del(&page->lru);
+ vb->pfns[vb->num_pfns] = page_to_pfn(page);
+ 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);
+ }
+}
+
+static void virtballoon_changed(struct virtio_device *vdev)
+{
+ struct virtio_balloon *vb = vdev->priv;
+
+ wake_up(&vb->config_change);
+}
+
+static inline int towards_target(struct virtio_balloon *vb)
+{
+ u32 v;
+ __virtio_config_val(vb->vdev,
+ offsetof(struct virtio_balloon_config, num_pages),
+ &v);
+ return v - vb->num_pages;
+}
+
+static void update_balloon_size(struct virtio_balloon *vb)
+{
+ __le32 actual = cpu_to_le32(vb->num_pages);
+
+ vb->vdev->config->set(vb->vdev,
+ offsetof(struct virtio_balloon_config, actual),
+ &actual, sizeof(actual));
+}
+
+static int balloon(void *_vballoon)
+{
+ struct virtio_balloon *vb = _vballoon;
+
+ set_freezable();
+ while (!kthread_should_stop()) {
+ int diff;
+
+ try_to_freeze();
+ wait_event_interruptible(vb->config_change,
+ (diff = towards_target(vb)) != 0
+ || kthread_should_stop());
+ if (diff > 0)
+ fill_balloon(vb, diff);
+ else if (diff < 0)
+ leak_balloon(vb, -diff);
+ update_balloon_size(vb);
+ }
+ return 0;
+}
+
+static int virtballoon_probe(struct virtio_device *vdev)
+{
+ struct virtio_balloon *vb;
+ int err;
+
+ vdev->priv = vb = kmalloc(sizeof(*vb), GFP_KERNEL);
+ if (!vb) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ INIT_LIST_HEAD(&vb->pages);
+ vb->num_pages = 0;
+ init_waitqueue_head(&vb->config_change);
+ vb->vdev = vdev;
+
+ /* We expect two virtqueues. */
+ vb->inflate_vq = vdev->config->find_vq(vdev, 0, balloon_ack);
+ if (IS_ERR(vb->inflate_vq)) {
+ err = PTR_ERR(vb->inflate_vq);
+ goto out_free_vb;
+ }
+
+ vb->deflate_vq = vdev->config->find_vq(vdev, 1, balloon_ack);
+ if (IS_ERR(vb->deflate_vq)) {
+ err = PTR_ERR(vb->deflate_vq);
+ goto out_del_inflate_vq;
+ }
+
+ vb->thread = kthread_run(balloon, vb, "vballoon");
+ if (IS_ERR(vb->thread)) {
+ err = PTR_ERR(vb->thread);
+ goto out_del_deflate_vq;
+ }
+
+ vb->tell_host_first
+ = vdev->config->feature(vdev, VIRTIO_BALLOON_F_MUST_TELL_HOST);
+
+ return 0;
+
+out_del_deflate_vq:
+ vdev->config->del_vq(vb->deflate_vq);
+out_del_inflate_vq:
+ vdev->config->del_vq(vb->inflate_vq);
+out_free_vb:
+ kfree(vb);
+out:
+ return err;
+}
+
+static void virtballoon_remove(struct virtio_device *vdev)
+{
+ struct virtio_balloon *vb = vdev->priv;
+
+ kthread_stop(vb->thread);
+
+ /* There might be pages left in the balloon: free them. */
+ while (vb->num_pages)
+ leak_balloon(vb, vb->num_pages);
+
+ /* Now we reset the device so we can clean up the queues. */
+ vdev->config->reset(vdev);
+
+ vdev->config->del_vq(vb->deflate_vq);
+ vdev->config->del_vq(vb->inflate_vq);
+ kfree(vb);
+}
+
+static struct virtio_driver virtio_balloon = {
+ .driver.name = KBUILD_MODNAME,
+ .driver.owner = THIS_MODULE,
+ .id_table = id_table,
+ .probe = virtballoon_probe,
+ .remove = __devexit_p(virtballoon_remove),
+ .config_changed = virtballoon_changed,
+};
+
+static int __init init(void)
+{
+ return register_virtio_driver(&virtio_balloon);
+}
+
+static void __exit fini(void)
+{
+ unregister_virtio_driver(&virtio_balloon);
+}
+module_init(init);
+module_exit(fini);
+
+MODULE_DEVICE_TABLE(virtio, id_table);
+MODULE_DESCRIPTION("Virtio balloon driver");
+MODULE_LICENSE("GPL");
--- /dev/null
+/*
+ * Virtio PCI driver
+ *
+ * This module allows virtio devices to be used over a virtual PCI device.
+ * This can be used with QEMU based VMMs like KVM or Xen.
+ *
+ * Copyright IBM Corp. 2007
+ *
+ * Authors:
+ * Anthony Liguori <aliguori@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/pci.h>
+#include <linux/interrupt.h>
+#include <linux/virtio.h>
+#include <linux/virtio_config.h>
+#include <linux/virtio_ring.h>
+#include <linux/virtio_pci.h>
+#include <linux/highmem.h>
+#include <linux/spinlock.h>
+
+MODULE_AUTHOR("Anthony Liguori <aliguori@us.ibm.com>");
+MODULE_DESCRIPTION("virtio-pci");
+MODULE_LICENSE("GPL");
+MODULE_VERSION("1");
+
+/* Our device structure */
+struct virtio_pci_device
+{
+ struct virtio_device vdev;
+ struct pci_dev *pci_dev;
+
+ /* the IO mapping for the PCI config space */
+ void *ioaddr;
+
+ /* a list of queues so we can dispatch IRQs */
+ spinlock_t lock;
+ struct list_head virtqueues;
+};
+
+struct virtio_pci_vq_info
+{
+ /* the actual virtqueue */
+ struct virtqueue *vq;
+
+ /* the number of entries in the queue */
+ int num;
+
+ /* the index of the queue */
+ int queue_index;
+
+ /* the virtual address of the ring queue */
+ void *queue;
+
+ /* the list node for the virtqueues list */
+ struct list_head node;
+};
+
+/* Qumranet donated their vendor ID for devices 0x1000 thru 0x10FF. */
+static struct pci_device_id virtio_pci_id_table[] = {
+ { 0x1af4, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
+ { 0 },
+};
+
+MODULE_DEVICE_TABLE(pci, virtio_pci_id_table);
+
+/* A PCI device has it's own struct device and so does a virtio device so
+ * we create a place for the virtio devices to show up in sysfs. I think it
+ * would make more sense for virtio to not insist on having it's own device. */
+static struct device virtio_pci_root = {
+ .parent = NULL,
+ .bus_id = "virtio-pci",
+};
+
+/* Unique numbering for devices under the kvm root */
+static unsigned int dev_index;
+
+/* Convert a generic virtio device to our structure */
+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)
+{
+ 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);
+ }
+
+ return !!(mask & (1 << bit));
+}
+
+/* virtio config->get() implementation */
+static void vp_get(struct virtio_device *vdev, unsigned offset,
+ void *buf, unsigned len)
+{
+ struct virtio_pci_device *vp_dev = to_vp_device(vdev);
+ void *ioaddr = vp_dev->ioaddr + VIRTIO_PCI_CONFIG + offset;
+ u8 *ptr = buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ ptr[i] = ioread8(ioaddr + i);
+}
+
+/* the config->set() implementation. it's symmetric to the config->get()
+ * implementation */
+static void vp_set(struct virtio_device *vdev, unsigned offset,
+ const void *buf, unsigned len)
+{
+ struct virtio_pci_device *vp_dev = to_vp_device(vdev);
+ void *ioaddr = vp_dev->ioaddr + VIRTIO_PCI_CONFIG + offset;
+ const u8 *ptr = buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ iowrite8(ptr[i], ioaddr + i);
+}
+
+/* config->{get,set}_status() implementations */
+static u8 vp_get_status(struct virtio_device *vdev)
+{
+ struct virtio_pci_device *vp_dev = to_vp_device(vdev);
+ return ioread8(vp_dev->ioaddr + VIRTIO_PCI_STATUS);
+}
+
+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);
+}
+
+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);
+}
+
+/* the notify function used when creating a virt queue */
+static void vp_notify(struct virtqueue *vq)
+{
+ struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
+ struct virtio_pci_vq_info *info = vq->priv;
+
+ /* we write the queue's selector into the notification register to
+ * signal the other end */
+ iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
+}
+
+/* A small wrapper to also acknowledge the interrupt when it's handled.
+ * I really need an EIO hook for the vring so I can ack the interrupt once we
+ * know that we'll be handling the IRQ but before we invoke the callback since
+ * the callback may notify the host which results in the host attempting to
+ * raise an interrupt that we would then mask once we acknowledged the
+ * interrupt. */
+static irqreturn_t vp_interrupt(int irq, void *opaque)
+{
+ struct virtio_pci_device *vp_dev = opaque;
+ struct virtio_pci_vq_info *info;
+ irqreturn_t ret = IRQ_NONE;
+ u8 isr;
+
+ /* reading the ISR has the effect of also clearing it so it's very
+ * important to save off the value. */
+ isr = ioread8(vp_dev->ioaddr + VIRTIO_PCI_ISR);
+
+ /* It's definitely not us if the ISR was not high */
+ if (!isr)
+ return IRQ_NONE;
+
+ /* Configuration change? Tell driver if it wants to know. */
+ if (isr & VIRTIO_PCI_ISR_CONFIG) {
+ struct virtio_driver *drv;
+ drv = container_of(vp_dev->vdev.dev.driver,
+ struct virtio_driver, driver);
+
+ if (drv->config_changed)
+ drv->config_changed(&vp_dev->vdev);
+ }
+
+ spin_lock(&vp_dev->lock);
+ list_for_each_entry(info, &vp_dev->virtqueues, node) {
+ if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)
+ ret = IRQ_HANDLED;
+ }
+ spin_unlock(&vp_dev->lock);
+
+ return ret;
+}
+
+/* the config->find_vq() implementation */
+static struct virtqueue *vp_find_vq(struct virtio_device *vdev, unsigned index,
+ void (*callback)(struct virtqueue *vq))
+{
+ struct virtio_pci_device *vp_dev = to_vp_device(vdev);
+ struct virtio_pci_vq_info *info;
+ struct virtqueue *vq;
+ u16 num;
+ int err;
+
+ /* Select the queue we're interested in */
+ iowrite16(index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
+
+ /* Check if queue is either not available or already active. */
+ num = ioread16(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NUM);
+ if (!num || ioread32(vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN))
+ return ERR_PTR(-ENOENT);
+
+ /* allocate and fill out our structure the represents an active
+ * queue */
+ info = kmalloc(sizeof(struct virtio_pci_vq_info), GFP_KERNEL);
+ if (!info)
+ return ERR_PTR(-ENOMEM);
+
+ info->queue_index = index;
+ info->num = num;
+
+ info->queue = kzalloc(PAGE_ALIGN(vring_size(num,PAGE_SIZE)), GFP_KERNEL);
+ if (info->queue == NULL) {
+ err = -ENOMEM;
+ goto out_info;
+ }
+
+ /* activate the queue */
+ iowrite32(virt_to_phys(info->queue) >> PAGE_SHIFT,
+ vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
+
+ /* create the vring */
+ vq = vring_new_virtqueue(info->num, vdev, info->queue,
+ vp_notify, callback);
+ if (!vq) {
+ err = -ENOMEM;
+ goto out_activate_queue;
+ }
+
+ vq->priv = info;
+ info->vq = vq;
+
+ spin_lock(&vp_dev->lock);
+ list_add(&info->node, &vp_dev->virtqueues);
+ spin_unlock(&vp_dev->lock);
+
+ return vq;
+
+out_activate_queue:
+ iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
+ kfree(info->queue);
+out_info:
+ kfree(info);
+ return ERR_PTR(err);
+}
+
+/* the config->del_vq() implementation */
+static void vp_del_vq(struct virtqueue *vq)
+{
+ struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
+ struct virtio_pci_vq_info *info = vq->priv;
+
+ spin_lock(&vp_dev->lock);
+ list_del(&info->node);
+ spin_unlock(&vp_dev->lock);
+
+ vring_del_virtqueue(vq);
+
+ /* Select and deactivate the queue */
+ iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_SEL);
+ iowrite32(0, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_PFN);
+
+ kfree(info->queue);
+ kfree(info);
+}
+
+static struct virtio_config_ops virtio_pci_config_ops = {
+ .feature = vp_feature,
+ .get = vp_get,
+ .set = vp_set,
+ .get_status = vp_get_status,
+ .set_status = vp_set_status,
+ .reset = vp_reset,
+ .find_vq = vp_find_vq,
+ .del_vq = vp_del_vq,
+};
+
+/* the PCI probing function */
+static int __devinit virtio_pci_probe(struct pci_dev *pci_dev,
+ const struct pci_device_id *id)
+{
+ struct virtio_pci_device *vp_dev;
+ int err;
+
+ /* We only own devices >= 0x1000 and <= 0x103f: leave the rest. */
+ if (pci_dev->device < 0x1000 || pci_dev->device > 0x103f)
+ return -ENODEV;
+
+ if (pci_dev->revision != VIRTIO_PCI_ABI_VERSION) {
+ printk(KERN_ERR "virtio_pci: expected ABI version %d, got %d\n",
+ VIRTIO_PCI_ABI_VERSION, pci_dev->revision);
+ return -ENODEV;
+ }
+
+ /* allocate our structure and fill it out */
+ vp_dev = kzalloc(sizeof(struct virtio_pci_device), GFP_KERNEL);
+ if (vp_dev == NULL)
+ return -ENOMEM;
+
+ snprintf(vp_dev->vdev.dev.bus_id, BUS_ID_SIZE, "virtio%d", dev_index);
+ vp_dev->vdev.index = dev_index;
+ dev_index++;
+
+ vp_dev->vdev.dev.parent = &virtio_pci_root;
+ vp_dev->vdev.config = &virtio_pci_config_ops;
+ vp_dev->pci_dev = pci_dev;
+ INIT_LIST_HEAD(&vp_dev->virtqueues);
+ spin_lock_init(&vp_dev->lock);
+
+ /* enable the device */
+ err = pci_enable_device(pci_dev);
+ if (err)
+ goto out;
+
+ err = pci_request_regions(pci_dev, "virtio-pci");
+ if (err)
+ goto out_enable_device;
+
+ vp_dev->ioaddr = pci_iomap(pci_dev, 0, 0);
+ if (vp_dev->ioaddr == NULL)
+ goto out_req_regions;
+
+ pci_set_drvdata(pci_dev, vp_dev);
+
+ /* we use the subsystem vendor/device id as the virtio vendor/device
+ * id. this allows us to use the same PCI vendor/device id for all
+ * virtio devices and to identify the particular virtio driver by
+ * the subsytem ids */
+ vp_dev->vdev.id.vendor = pci_dev->subsystem_vendor;
+ vp_dev->vdev.id.device = pci_dev->subsystem_device;
+
+ /* register a handler for the queue with the PCI device's interrupt */
+ err = request_irq(vp_dev->pci_dev->irq, vp_interrupt, IRQF_SHARED,
+ vp_dev->vdev.dev.bus_id, vp_dev);
+ if (err)
+ goto out_set_drvdata;
+
+ /* finally register the virtio device */
+ err = register_virtio_device(&vp_dev->vdev);
+ if (err)
+ goto out_req_irq;
+
+ return 0;
+
+out_req_irq:
+ free_irq(pci_dev->irq, vp_dev);
+out_set_drvdata:
+ pci_set_drvdata(pci_dev, NULL);
+ pci_iounmap(pci_dev, vp_dev->ioaddr);
+out_req_regions:
+ pci_release_regions(pci_dev);
+out_enable_device:
+ pci_disable_device(pci_dev);
+out:
+ kfree(vp_dev);
+ return err;
+}
+
+static void __devexit virtio_pci_remove(struct pci_dev *pci_dev)
+{
+ struct virtio_pci_device *vp_dev = pci_get_drvdata(pci_dev);
+
+ free_irq(pci_dev->irq, vp_dev);
+ pci_set_drvdata(pci_dev, NULL);
+ pci_iounmap(pci_dev, vp_dev->ioaddr);
+ pci_release_regions(pci_dev);
+ pci_disable_device(pci_dev);
+ kfree(vp_dev);
+}
+
+#ifdef CONFIG_PM
+static int virtio_pci_suspend(struct pci_dev *pci_dev, pm_message_t state)
+{
+ pci_save_state(pci_dev);
+ pci_set_power_state(pci_dev, PCI_D3hot);
+ return 0;
+}
+
+static int virtio_pci_resume(struct pci_dev *pci_dev)
+{
+ pci_restore_state(pci_dev);
+ pci_set_power_state(pci_dev, PCI_D0);
+ return 0;
+}
+#endif
+
+static struct pci_driver virtio_pci_driver = {
+ .name = "virtio-pci",
+ .id_table = virtio_pci_id_table,
+ .probe = virtio_pci_probe,
+ .remove = virtio_pci_remove,
+#ifdef CONFIG_PM
+ .suspend = virtio_pci_suspend,
+ .resume = virtio_pci_resume,
+#endif
+};
+
+static int __init virtio_pci_init(void)
+{
+ int err;
+
+ err = device_register(&virtio_pci_root);
+ if (err)
+ return err;
+
+ err = pci_register_driver(&virtio_pci_driver);
+ if (err)
+ device_unregister(&virtio_pci_root);
+
+ return err;
+}
+
+module_init(virtio_pci_init);
+
+static void __exit virtio_pci_exit(void)
+{
+ device_unregister(&virtio_pci_root);
+ pci_unregister_driver(&virtio_pci_driver);
+}
+
+module_exit(virtio_pci_exit);
if (vq->num_free < out + in) {
pr_debug("Can't add buf len %i - avail = %i\n",
out + in, vq->num_free);
+ /* We notify *even if* VRING_USED_F_NO_NOTIFY is set here. */
+ vq->notify(&vq->vq);
END_USE(vq);
return -ENOSPC;
}
head = vq->free_head;
for (i = vq->free_head; out; i = vq->vring.desc[i].next, out--) {
vq->vring.desc[i].flags = VRING_DESC_F_NEXT;
- vq->vring.desc[i].addr = (page_to_pfn(sg_page(sg))<<PAGE_SHIFT)
- + sg->offset;
+ vq->vring.desc[i].addr = sg_phys(sg);
vq->vring.desc[i].len = sg->length;
prev = i;
sg++;
}
for (; in; i = vq->vring.desc[i].next, in--) {
vq->vring.desc[i].flags = VRING_DESC_F_NEXT|VRING_DESC_F_WRITE;
- vq->vring.desc[i].addr = (page_to_pfn(sg_page(sg))<<PAGE_SHIFT)
- + sg->offset;
+ vq->vring.desc[i].addr = sg_phys(sg);
vq->vring.desc[i].len = sg->length;
prev = i;
sg++;
vq->num_free++;
}
-/* FIXME: We need to tell other side about removal, to synchronize. */
-static void vring_shutdown(struct virtqueue *_vq)
-{
- struct vring_virtqueue *vq = to_vvq(_vq);
- unsigned int i;
-
- for (i = 0; i < vq->vring.num; i++)
- detach_buf(vq, i);
-}
-
static inline bool more_used(const struct vring_virtqueue *vq)
{
return vq->last_used_idx != vq->vring.used->idx;
return ret;
}
-static bool vring_restart(struct virtqueue *_vq)
+static void vring_disable_cb(struct virtqueue *_vq)
+{
+ struct vring_virtqueue *vq = to_vvq(_vq);
+
+ START_USE(vq);
+ BUG_ON(vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT);
+ vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
+ END_USE(vq);
+}
+
+static bool vring_enable_cb(struct virtqueue *_vq)
{
struct vring_virtqueue *vq = to_vvq(_vq);
if (unlikely(vq->broken))
return IRQ_HANDLED;
+ /* Other side may have missed us turning off the interrupt,
+ * but we should preserve disable semantic for virtio users. */
+ if (unlikely(vq->vring.avail->flags & VRING_AVAIL_F_NO_INTERRUPT)) {
+ pr_debug("virtqueue interrupt after disable for %p\n", vq);
+ return IRQ_HANDLED;
+ }
+
pr_debug("virtqueue callback for %p (%p)\n", vq, vq->vq.callback);
- if (vq->vq.callback && !vq->vq.callback(&vq->vq))
- vq->vring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT;
+ if (vq->vq.callback)
+ vq->vq.callback(&vq->vq);
return IRQ_HANDLED;
}
+EXPORT_SYMBOL_GPL(vring_interrupt);
static struct virtqueue_ops vring_vq_ops = {
.add_buf = vring_add_buf,
.get_buf = vring_get_buf,
.kick = vring_kick,
- .restart = vring_restart,
- .shutdown = vring_shutdown,
+ .disable_cb = vring_disable_cb,
+ .enable_cb = vring_enable_cb,
};
struct virtqueue *vring_new_virtqueue(unsigned int num,
struct virtio_device *vdev,
void *pages,
void (*notify)(struct virtqueue *),
- bool (*callback)(struct virtqueue *))
+ void (*callback)(struct virtqueue *))
{
struct vring_virtqueue *vq;
unsigned int i;
return &vq->vq;
}
+EXPORT_SYMBOL_GPL(vring_new_virtqueue);
void vring_del_virtqueue(struct virtqueue *vq)
{
kfree(to_vvq(vq));
}
+EXPORT_SYMBOL_GPL(vring_del_virtqueue);
+MODULE_LICENSE("GPL");
struct lguest_device_desc {
/* The device type: console, network, disk etc. Type 0 terminates. */
__u8 type;
- /* The number of bytes of the config array. */
+ /* The number of virtqueues (first in config array) */
+ __u8 num_vq;
+ /* The number of bytes of feature bits. Multiply by 2: one for host
+ * features and one for guest acknowledgements. */
+ __u8 feature_len;
+ /* The number of bytes of the config array after virtqueues. */
__u8 config_len;
/* A status byte, written by the Guest. */
__u8 status;
};
/*D:135 This is how we expect the device configuration field for a virtqueue
- * (type VIRTIO_CONFIG_F_VIRTQUEUE) to be laid out: */
+ * to be laid out in config space. */
struct lguest_vqconfig {
/* The number of entries in the virtio_ring */
__u16 num;
skb->ip_summed = CHECKSUM_NONE;
}
+bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off);
#endif /* __KERNEL__ */
#endif /* _LINUX_SKBUFF_H */
/**
* virtqueue - a queue to register buffers for sending or receiving.
* @callback: the function to call when buffers are consumed (can be NULL).
- * If this returns false, callbacks are suppressed until vq_ops->restart
- * is called.
* @vdev: the virtio device this queue was created for.
* @vq_ops: the operations for this virtqueue (see below).
* @priv: a pointer for the virtqueue implementation to use.
*/
struct virtqueue
{
- bool (*callback)(struct virtqueue *vq);
+ void (*callback)(struct virtqueue *vq);
struct virtio_device *vdev;
struct virtqueue_ops *vq_ops;
void *priv;
* vq: the struct virtqueue we're talking about.
* len: the length written into the buffer
* Returns NULL or the "data" token handed to add_buf.
- * @restart: restart callbacks after callback returned false.
+ * @disable_cb: disable callbacks
+ * vq: the struct virtqueue we're talking about.
+ * @enable_cb: restart callbacks after disable_cb.
* vq: the struct virtqueue we're talking about.
* This returns "false" (and doesn't re-enable) if there are pending
* buffers in the queue, to avoid a race.
- * @shutdown: "unadd" all buffers.
- * vq: the struct virtqueue we're talking about.
- * Remove everything from the queue.
*
* Locking rules are straightforward: the driver is responsible for
* locking. No two operations may be invoked simultaneously.
void *(*get_buf)(struct virtqueue *vq, unsigned int *len);
- bool (*restart)(struct virtqueue *vq);
-
- void (*shutdown)(struct virtqueue *vq);
+ void (*disable_cb)(struct virtqueue *vq);
+ bool (*enable_cb)(struct virtqueue *vq);
};
/**
* @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.
+ * @config_changed: optional function to call when the device configuration
+ * changes; may be called in interrupt context.
*/
struct virtio_driver {
struct device_driver driver;
const struct virtio_device_id *id_table;
int (*probe)(struct virtio_device *dev);
void (*remove)(struct virtio_device *dev);
+ void (*config_changed)(struct virtio_device *dev);
};
int register_virtio_driver(struct virtio_driver *drv);
--- /dev/null
+#ifndef _LINUX_VIRTIO_BALLOON_H
+#define _LINUX_VIRTIO_BALLOON_H
+#include <linux/virtio_config.h>
+
+/* The ID for virtio_balloon */
+#define VIRTIO_ID_BALLOON 5
+
+/* The feature bitmap for virtio balloon */
+#define VIRTIO_BALLOON_F_MUST_TELL_HOST 0 /* Tell before reclaiming pages */
+
+struct virtio_balloon_config
+{
+ /* Number of pages host wants Guest to give up. */
+ __le32 num_pages;
+ /* Number of pages we've actually got in balloon. */
+ __le32 actual;
+};
+#endif /* _LINUX_VIRTIO_BALLOON_H */
#define VIRTIO_ID_BLOCK 2
/* Feature bits */
-#define VIRTIO_CONFIG_BLK_F 0x40
-#define VIRTIO_BLK_F_BARRIER 1 /* Does host support barriers? */
+#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 */
-/* The capacity (in 512-byte sectors). */
-#define VIRTIO_CONFIG_BLK_F_CAPACITY 0x41
-/* The maximum segment size. */
-#define VIRTIO_CONFIG_BLK_F_SIZE_MAX 0x42
-/* The maximum number of segments. */
-#define VIRTIO_CONFIG_BLK_F_SEG_MAX 0x43
+struct virtio_blk_config
+{
+ /* The capacity (in 512-byte sectors). */
+ __le64 capacity;
+ /* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */
+ __le32 size_max;
+ /* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */
+ __le32 seg_max;
+} __attribute__((packed));
/* These two define direction. */
#define VIRTIO_BLK_T_IN 0
__u32 ioprio;
/* Sector (ie. 512 byte offset) */
__u64 sector;
- /* Where to put reply. */
- __u64 id;
};
#define VIRTIO_BLK_S_OK 0
* store and access that space differently. */
#include <linux/types.h>
-/* Status byte for guest to report progress, and synchronize config. */
+/* Status byte for guest to report progress, and synchronize features. */
/* We have seen device and processed generic fields (VIRTIO_CONFIG_F_VIRTIO) */
#define VIRTIO_CONFIG_S_ACKNOWLEDGE 1
/* We have found a driver for the device. */
/* We've given up on this device. */
#define VIRTIO_CONFIG_S_FAILED 0x80
-/* Feature byte (actually 7 bits availabe): */
-/* Requirements/features of the virtio implementation. */
-#define VIRTIO_CONFIG_F_VIRTIO 1
-/* Requirements/features of the virtqueue (may have more than one). */
-#define VIRTIO_CONFIG_F_VIRTQUEUE 2
-
#ifdef __KERNEL__
struct virtio_device;
/**
* virtio_config_ops - operations for configuring a virtio device
- * @find: search for the next configuration field of the given type.
+ * @feature: search for a feature in this config
* vdev: the virtio_device
- * type: the feature type
- * len: the (returned) length of the field if found.
- * Returns a token if found, or NULL. Never returnes the same field twice
- * (ie. it's used up).
- * @get: read the value of a configuration field after find().
+ * 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
- * token: the token returned from find().
+ * offset: the offset of the configuration field
* buf: the buffer to write the field value into.
- * len: the length of the buffer (given by find()).
+ * len: the length of the buffer
* Note that contents are conventionally little-endian.
- * @set: write the value of a configuration field after find().
+ * @set: write the value of a configuration field
* vdev: the virtio_device
- * token: the token returned from find().
+ * offset: the offset of the configuration field
* buf: the buffer to read the field value from.
- * len: the length of the buffer (given by find()).
+ * len: the length of the buffer
* Note that contents are conventionally little-endian.
* @get_status: read the status byte
* vdev: the virtio_device
* @set_status: write the status byte
* vdev: the virtio_device
* status: the new status byte
- * @find_vq: find the first VIRTIO_CONFIG_F_VIRTQUEUE and create a virtqueue.
+ * @reset: reset the device
+ * vdev: the virtio device
+ * After this, status and feature negotiation must be done again
+ * @find_vq: find a virtqueue and instantiate it.
* vdev: the virtio_device
+ * index: the 0-based virtqueue number in case there's more than one.
* callback: the virqtueue callback
- * Returns the new virtqueue or ERR_PTR().
+ * Returns the new virtqueue or ERR_PTR() (eg. -ENOENT).
* @del_vq: free a virtqueue found by find_vq().
*/
struct virtio_config_ops
{
- void *(*find)(struct virtio_device *vdev, u8 type, unsigned *len);
- void (*get)(struct virtio_device *vdev, void *token,
+ 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, void *token,
+ void (*set)(struct virtio_device *vdev, unsigned offset,
const void *buf, unsigned len);
u8 (*get_status)(struct virtio_device *vdev);
void (*set_status)(struct virtio_device *vdev, u8 status);
+ void (*reset)(struct virtio_device *vdev);
struct virtqueue *(*find_vq)(struct virtio_device *vdev,
- bool (*callback)(struct virtqueue *));
+ unsigned index,
+ void (*callback)(struct virtqueue *));
void (*del_vq)(struct virtqueue *vq);
};
/**
- * virtio_config_val - get a single virtio config and mark it used.
- * @config: the virtio config space
- * @type: the type to search for.
+ * virtio_config_val - look for a feature and get a single virtio config.
+ * @vdev: the virtio device
+ * @fbit: the feature bit
+ * @offset: the type to search for.
* @val: a pointer to the value to fill in.
*
- * Once used, the config type is marked with VIRTIO_CONFIG_F_USED so it can't
- * be found again. This version does endian conversion. */
-#define virtio_config_val(vdev, type, v) ({ \
- int _err = __virtio_config_val((vdev),(type),(v),sizeof(*(v))); \
- \
- BUILD_BUG_ON(sizeof(*(v)) != 1 && sizeof(*(v)) != 2 \
- && sizeof(*(v)) != 4 && sizeof(*(v)) != 8); \
- if (!_err) { \
- 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; \
- } \
- } \
+ * 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; \
})
-int __virtio_config_val(struct virtio_device *dev,
- u8 type, void *val, size_t size);
-
/**
- * virtio_use_bit - helper to use a feature bit in a bitfield value.
- * @dev: the virtio device
- * @token: the token as returned from vdev->config->find().
- * @len: the length of the field.
- * @bitnum: the bit to test.
+ * __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.
*
- * If handed a NULL token, it returns false, otherwise returns bit status.
- * If it's one, it sets the mirroring acknowledgement bit. */
-int virtio_use_bit(struct virtio_device *vdev,
- void *token, unsigned int len, unsigned int bitnum);
+ * 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)
#endif /* __KERNEL__ */
#endif /* _LINUX_VIRTIO_CONFIG_H */
/* The ID for virtio_net */
#define VIRTIO_ID_NET 1
-/* The bitmap of config for virtio net */
-#define VIRTIO_CONFIG_NET_F 0x40
-#define VIRTIO_NET_F_NO_CSUM 0
-#define VIRTIO_NET_F_TSO4 1
-#define VIRTIO_NET_F_UFO 2
-#define VIRTIO_NET_F_TSO4_ECN 3
-#define VIRTIO_NET_F_TSO6 4
+/* The feature bitmap for virtio net */
+#define VIRTIO_NET_F_CSUM 0 /* Can handle 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 */
-/* The config defining mac address. */
-#define VIRTIO_CONFIG_NET_MAC_F 0x41
+struct virtio_net_config
+{
+ /* The config defining mac address (if VIRTIO_NET_F_MAC) */
+ __u8 mac[6];
+} __attribute__((packed));
/* This is the first element of the scatter-gather list. If you don't
* specify GSO or CSUM features, you can simply ignore the header. */
struct virtio_net_hdr
{
#define VIRTIO_NET_HDR_F_NEEDS_CSUM 1 // Use csum_start, csum_offset
- __u8 flags;
+ __u8 flags;
#define VIRTIO_NET_HDR_GSO_NONE 0 // Not a GSO frame
#define VIRTIO_NET_HDR_GSO_TCPV4 1 // GSO frame, IPv4 TCP (TSO)
-/* FIXME: Do we need this? If they said they can handle ECN, do they care? */
-#define VIRTIO_NET_HDR_GSO_TCPV4_ECN 2 // GSO frame, IPv4 TCP w/ ECN
#define VIRTIO_NET_HDR_GSO_UDP 3 // GSO frame, IPv4 UDP (UFO)
#define VIRTIO_NET_HDR_GSO_TCPV6 4 // GSO frame, IPv6 TCP
- __u8 gso_type;
- __u16 gso_size;
- __u16 csum_start;
- __u16 csum_offset;
+#define VIRTIO_NET_HDR_GSO_ECN 0x80 // TCP has ECN set
+ __u8 gso_type;
+ __u16 hdr_len; /* Ethernet + IP + tcp/udp hdrs */
+ __u16 gso_size; /* Bytes to append to gso_hdr_len per frame */
+ __u16 csum_start; /* Position to start checksumming from */
+ __u16 csum_offset; /* Offset after that to place checksum */
};
#endif /* _LINUX_VIRTIO_NET_H */
--- /dev/null
+/*
+ * Virtio PCI driver
+ *
+ * This module allows virtio devices to be used over a virtual PCI device.
+ * This can be used with QEMU based VMMs like KVM or Xen.
+ *
+ * Copyright IBM Corp. 2007
+ *
+ * Authors:
+ * Anthony Liguori <aliguori@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#ifndef _LINUX_VIRTIO_PCI_H
+#define _LINUX_VIRTIO_PCI_H
+
+#include <linux/virtio_config.h>
+
+/* A 32-bit r/o bitmask of the features supported by the host */
+#define VIRTIO_PCI_HOST_FEATURES 0
+
+/* A 32-bit r/w bitmask of features activated by the guest */
+#define VIRTIO_PCI_GUEST_FEATURES 4
+
+/* A 32-bit r/w PFN for the currently selected queue */
+#define VIRTIO_PCI_QUEUE_PFN 8
+
+/* A 16-bit r/o queue size for the currently selected queue */
+#define VIRTIO_PCI_QUEUE_NUM 12
+
+/* A 16-bit r/w queue selector */
+#define VIRTIO_PCI_QUEUE_SEL 14
+
+/* A 16-bit r/w queue notifier */
+#define VIRTIO_PCI_QUEUE_NOTIFY 16
+
+/* An 8-bit device status register. */
+#define VIRTIO_PCI_STATUS 18
+
+/* An 8-bit r/o interrupt status register. Reading the value will return the
+ * current contents of the ISR and will also clear it. This is effectively
+ * a read-and-acknowledge. */
+#define VIRTIO_PCI_ISR 19
+
+/* The bit of the ISR which indicates a device configuration change. */
+#define VIRTIO_PCI_ISR_CONFIG 0x2
+
+/* The remaining space is defined by each driver as the per-driver
+ * configuration space */
+#define VIRTIO_PCI_CONFIG 20
+
+/* Virtio ABI version, this must match exactly */
+#define VIRTIO_PCI_ABI_VERSION 0
+#endif
/* This marks a buffer as write-only (otherwise read-only). */
#define VRING_DESC_F_WRITE 2
-/* This means don't notify other side when buffer added. */
+/* The Host uses this in used->flags to advise the Guest: don't kick me when
+ * you add a buffer. It's unreliable, so it's simply an optimization. Guest
+ * will still kick if it's out of buffers. */
#define VRING_USED_F_NO_NOTIFY 1
-/* This means don't interrupt guest when buffer consumed. */
+/* The Guest uses this in avail->flags to advise the Host: don't interrupt me
+ * when you consume a buffer. It's unreliable, so it's simply an
+ * optimization. */
#define VRING_AVAIL_F_NO_INTERRUPT 1
/* Virtio ring descriptors: 16 bytes. These can chain together via "next". */
* };
*/
static inline void vring_init(struct vring *vr, unsigned int num, void *p,
- unsigned int pagesize)
+ unsigned long pagesize)
{
vr->num = num;
vr->desc = p;
& ~(pagesize - 1));
}
-static inline unsigned vring_size(unsigned int num, unsigned int pagesize)
+static inline unsigned vring_size(unsigned int num, unsigned long pagesize)
{
return ((sizeof(struct vring_desc) * num + sizeof(__u16) * (2 + num)
+ pagesize - 1) & ~(pagesize - 1))
struct virtio_device *vdev,
void *pages,
void (*notify)(struct virtqueue *vq),
- bool (*callback)(struct virtqueue *vq));
+ void (*callback)(struct virtqueue *vq));
void vring_del_virtqueue(struct virtqueue *vq);
irqreturn_t vring_interrupt(int irq, void *_vq);
kfree(trans);
}
-static bool p9_virtio_intr(struct virtqueue *q)
+static void p9_virtio_intr(struct virtqueue *q)
{
struct virtio_chan *chan = q->vdev->priv;
P9_DPRINTK(P9_DEBUG_TRANS, "9p poll_wakeup: %p\n", &chan->wq);
wake_up_interruptible(&chan->wq);
-
- return true;
}
static int p9_virtio_probe(struct virtio_device *dev)
/* Find the input queue. */
dev->priv = chan;
- chan->in_vq = dev->config->find_vq(dev, p9_virtio_intr);
+ chan->in_vq = dev->config->find_vq(dev, 0, p9_virtio_intr);
if (IS_ERR(chan->in_vq)) {
err = PTR_ERR(chan->in_vq);
goto free;
}
- chan->out_vq = dev->config->find_vq(dev, NULL);
+ chan->out_vq = dev->config->find_vq(dev, 1, NULL);
if (IS_ERR(chan->out_vq)) {
err = PTR_ERR(chan->out_vq);
goto free_in_vq;
return elt;
}
+/**
+ * skb_partial_csum_set - set up and verify partial csum values for packet
+ * @skb: the skb to set
+ * @start: the number of bytes after skb->data to start checksumming.
+ * @off: the offset from start to place the checksum.
+ *
+ * For untrusted partially-checksummed packets, we need to make sure the values
+ * for skb->csum_start and skb->csum_offset are valid so we don't oops.
+ *
+ * This function checks and sets those values and skb->ip_summed: if this
+ * returns false you should drop the packet.
+ */
+bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off)
+{
+ if (unlikely(start > skb->len - 2) ||
+ unlikely((int)start + off > skb->len - 2)) {
+ if (net_ratelimit())
+ printk(KERN_WARNING
+ "bad partial csum: csum=%u/%u len=%u\n",
+ start, off, skb->len);
+ return false;
+ }
+ skb->ip_summed = CHECKSUM_PARTIAL;
+ skb->csum_start = skb_headroom(skb) + start;
+ skb->csum_offset = off;
+ return true;
+}
+
EXPORT_SYMBOL(___pskb_trim);
EXPORT_SYMBOL(__kfree_skb);
EXPORT_SYMBOL(kfree_skb);
EXPORT_SYMBOL_GPL(skb_to_sgvec);
EXPORT_SYMBOL_GPL(skb_cow_data);
+EXPORT_SYMBOL_GPL(skb_partial_csum_set);
git.samba.org / sfrench / cifs-2.6.git / commitdiff