#include <linux/eventfd.h>
#include <linux/vhost.h>
-#include <linux/socket.h> /* memcpy_fromiovec */
+#include <linux/uio.h>
#include <linux/mm.h>
#include <linux/mmu_context.h>
#include <linux/miscdevice.h>
#include <linux/mutex.h>
-#include <linux/rcupdate.h>
#include <linux/poll.h>
#include <linux/file.h>
#include <linux/highmem.h>
#include <linux/slab.h>
+#include <linux/vmalloc.h>
#include <linux/kthread.h>
#include <linux/cgroup.h>
+#include <linux/module.h>
+#include <linux/sort.h>
#include "vhost.h"
+static ushort max_mem_regions = 64;
+module_param(max_mem_regions, ushort, 0444);
+MODULE_PARM_DESC(max_mem_regions,
+ "Maximum number of memory regions in memory map. (default: 64)");
+
enum {
- VHOST_MEMORY_MAX_NREGIONS = 64,
VHOST_MEMORY_F_LOG = 0x1,
};
-#define vhost_used_event(vq) ((u16 __user *)&vq->avail->ring[vq->num])
-#define vhost_avail_event(vq) ((u16 __user *)&vq->used->ring[vq->num])
+#define vhost_used_event(vq) ((__virtio16 __user *)&vq->avail->ring[vq->num])
+#define vhost_avail_event(vq) ((__virtio16 __user *)&vq->used->ring[vq->num])
+
+#ifdef CONFIG_VHOST_CROSS_ENDIAN_LEGACY
+static void vhost_vq_reset_user_be(struct vhost_virtqueue *vq)
+{
+ vq->user_be = !virtio_legacy_is_little_endian();
+}
+
+static long vhost_set_vring_endian(struct vhost_virtqueue *vq, int __user *argp)
+{
+ struct vhost_vring_state s;
+
+ if (vq->private_data)
+ return -EBUSY;
+
+ if (copy_from_user(&s, argp, sizeof(s)))
+ return -EFAULT;
+
+ if (s.num != VHOST_VRING_LITTLE_ENDIAN &&
+ s.num != VHOST_VRING_BIG_ENDIAN)
+ return -EINVAL;
+
+ vq->user_be = s.num;
+
+ return 0;
+}
+
+static long vhost_get_vring_endian(struct vhost_virtqueue *vq, u32 idx,
+ int __user *argp)
+{
+ struct vhost_vring_state s = {
+ .index = idx,
+ .num = vq->user_be
+ };
+
+ if (copy_to_user(argp, &s, sizeof(s)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static void vhost_init_is_le(struct vhost_virtqueue *vq)
+{
+ /* Note for legacy virtio: user_be is initialized at reset time
+ * according to the host endianness. If userspace does not set an
+ * explicit endianness, the default behavior is native endian, as
+ * expected by legacy virtio.
+ */
+ vq->is_le = vhost_has_feature(vq, VIRTIO_F_VERSION_1) || !vq->user_be;
+}
+#else
+static void vhost_vq_reset_user_be(struct vhost_virtqueue *vq)
+{
+}
+
+static long vhost_set_vring_endian(struct vhost_virtqueue *vq, int __user *argp)
+{
+ return -ENOIOCTLCMD;
+}
+
+static long vhost_get_vring_endian(struct vhost_virtqueue *vq, u32 idx,
+ int __user *argp)
+{
+ return -ENOIOCTLCMD;
+}
+
+static void vhost_init_is_le(struct vhost_virtqueue *vq)
+{
+ if (vhost_has_feature(vq, VIRTIO_F_VERSION_1))
+ vq->is_le = true;
+}
+#endif /* CONFIG_VHOST_CROSS_ENDIAN_LEGACY */
static void vhost_poll_func(struct file *file, wait_queue_head_t *wqh,
poll_table *pt)
work->flushing = 0;
work->queue_seq = work->done_seq = 0;
}
+EXPORT_SYMBOL_GPL(vhost_work_init);
/* Init poll structure */
void vhost_poll_init(struct vhost_poll *poll, vhost_work_fn_t fn,
vhost_work_init(&poll->work, fn);
}
+EXPORT_SYMBOL_GPL(vhost_poll_init);
/* Start polling a file. We add ourselves to file's wait queue. The caller must
* keep a reference to a file until after vhost_poll_stop is called. */
return ret;
}
+EXPORT_SYMBOL_GPL(vhost_poll_start);
/* Stop polling a file. After this function returns, it becomes safe to drop the
* file reference. You must also flush afterwards. */
poll->wqh = NULL;
}
}
+EXPORT_SYMBOL_GPL(vhost_poll_stop);
static bool vhost_work_seq_done(struct vhost_dev *dev, struct vhost_work *work,
unsigned seq)
return left <= 0;
}
-static void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work)
+void vhost_work_flush(struct vhost_dev *dev, struct vhost_work *work)
{
unsigned seq;
int flushing;
spin_unlock_irq(&dev->work_lock);
BUG_ON(flushing < 0);
}
+EXPORT_SYMBOL_GPL(vhost_work_flush);
/* Flush any work that has been scheduled. When calling this, don't hold any
* locks that are also used by the callback. */
{
vhost_work_flush(poll->dev, &poll->work);
}
+EXPORT_SYMBOL_GPL(vhost_poll_flush);
void vhost_work_queue(struct vhost_dev *dev, struct vhost_work *work)
{
if (list_empty(&work->node)) {
list_add_tail(&work->node, &dev->work_list);
work->queue_seq++;
+ spin_unlock_irqrestore(&dev->work_lock, flags);
wake_up_process(dev->worker);
+ } else {
+ spin_unlock_irqrestore(&dev->work_lock, flags);
}
- spin_unlock_irqrestore(&dev->work_lock, flags);
}
+EXPORT_SYMBOL_GPL(vhost_work_queue);
void vhost_poll_queue(struct vhost_poll *poll)
{
vhost_work_queue(poll->dev, &poll->work);
}
+EXPORT_SYMBOL_GPL(vhost_poll_queue);
static void vhost_vq_reset(struct vhost_dev *dev,
struct vhost_virtqueue *vq)
vq->log_used = false;
vq->log_addr = -1ull;
vq->private_data = NULL;
+ vq->acked_features = 0;
vq->log_base = NULL;
vq->error_ctx = NULL;
vq->error = NULL;
vq->call_ctx = NULL;
vq->call = NULL;
vq->log_ctx = NULL;
+ vq->memory = NULL;
+ vq->is_le = virtio_legacy_is_little_endian();
+ vhost_vq_reset_user_be(vq);
}
static int vhost_worker(void *data)
/* Helper to allocate iovec buffers for all vqs. */
static long vhost_dev_alloc_iovecs(struct vhost_dev *dev)
{
+ struct vhost_virtqueue *vq;
int i;
for (i = 0; i < dev->nvqs; ++i) {
- dev->vqs[i]->indirect = kmalloc(sizeof *dev->vqs[i]->indirect *
- UIO_MAXIOV, GFP_KERNEL);
- dev->vqs[i]->log = kmalloc(sizeof *dev->vqs[i]->log * UIO_MAXIOV,
- GFP_KERNEL);
- dev->vqs[i]->heads = kmalloc(sizeof *dev->vqs[i]->heads *
- UIO_MAXIOV, GFP_KERNEL);
- if (!dev->vqs[i]->indirect || !dev->vqs[i]->log ||
- !dev->vqs[i]->heads)
+ vq = dev->vqs[i];
+ vq->indirect = kmalloc(sizeof *vq->indirect * UIO_MAXIOV,
+ GFP_KERNEL);
+ vq->log = kmalloc(sizeof *vq->log * UIO_MAXIOV, GFP_KERNEL);
+ vq->heads = kmalloc(sizeof *vq->heads * UIO_MAXIOV, GFP_KERNEL);
+ if (!vq->indirect || !vq->log || !vq->heads)
goto err_nomem;
}
return 0;
vhost_vq_free_iovecs(dev->vqs[i]);
}
-long vhost_dev_init(struct vhost_dev *dev,
+void vhost_dev_init(struct vhost_dev *dev,
struct vhost_virtqueue **vqs, int nvqs)
{
+ struct vhost_virtqueue *vq;
int i;
dev->vqs = vqs;
dev->worker = NULL;
for (i = 0; i < dev->nvqs; ++i) {
- dev->vqs[i]->log = NULL;
- dev->vqs[i]->indirect = NULL;
- dev->vqs[i]->heads = NULL;
- dev->vqs[i]->dev = dev;
- mutex_init(&dev->vqs[i]->mutex);
- vhost_vq_reset(dev, dev->vqs[i]);
- if (dev->vqs[i]->handle_kick)
- vhost_poll_init(&dev->vqs[i]->poll,
- dev->vqs[i]->handle_kick, POLLIN, dev);
+ vq = dev->vqs[i];
+ vq->log = NULL;
+ vq->indirect = NULL;
+ vq->heads = NULL;
+ vq->dev = dev;
+ mutex_init(&vq->mutex);
+ vhost_vq_reset(dev, vq);
+ if (vq->handle_kick)
+ vhost_poll_init(&vq->poll, vq->handle_kick,
+ POLLIN, dev);
}
-
- return 0;
}
+EXPORT_SYMBOL_GPL(vhost_dev_init);
/* Caller should have device mutex */
long vhost_dev_check_owner(struct vhost_dev *dev)
/* Are you the owner? If not, I don't think you mean to do that */
return dev->mm == current->mm ? 0 : -EPERM;
}
+EXPORT_SYMBOL_GPL(vhost_dev_check_owner);
struct vhost_attach_cgroups_struct {
struct vhost_work work;
{
return dev->mm;
}
+EXPORT_SYMBOL_GPL(vhost_dev_has_owner);
/* Caller should have device mutex */
long vhost_dev_set_owner(struct vhost_dev *dev)
err_mm:
return err;
}
+EXPORT_SYMBOL_GPL(vhost_dev_set_owner);
struct vhost_memory *vhost_dev_reset_owner_prepare(void)
{
return kmalloc(offsetof(struct vhost_memory, regions), GFP_KERNEL);
}
+EXPORT_SYMBOL_GPL(vhost_dev_reset_owner_prepare);
/* Caller should have device mutex */
void vhost_dev_reset_owner(struct vhost_dev *dev, struct vhost_memory *memory)
{
+ int i;
+
vhost_dev_cleanup(dev, true);
/* Restore memory to default empty mapping. */
memory->nregions = 0;
- RCU_INIT_POINTER(dev->memory, memory);
+ dev->memory = memory;
+ /* We don't need VQ locks below since vhost_dev_cleanup makes sure
+ * VQs aren't running.
+ */
+ for (i = 0; i < dev->nvqs; ++i)
+ dev->vqs[i]->memory = memory;
}
+EXPORT_SYMBOL_GPL(vhost_dev_reset_owner);
void vhost_dev_stop(struct vhost_dev *dev)
{
}
}
}
+EXPORT_SYMBOL_GPL(vhost_dev_stop);
/* Caller should have device mutex if and only if locked is set */
void vhost_dev_cleanup(struct vhost_dev *dev, bool locked)
fput(dev->log_file);
dev->log_file = NULL;
/* No one will access memory at this point */
- kfree(rcu_dereference_protected(dev->memory,
- locked ==
- lockdep_is_held(&dev->mutex)));
- RCU_INIT_POINTER(dev->memory, NULL);
+ kvfree(dev->memory);
+ dev->memory = NULL;
WARN_ON(!list_empty(&dev->work_list));
if (dev->worker) {
kthread_stop(dev->worker);
mmput(dev->mm);
dev->mm = NULL;
}
+EXPORT_SYMBOL_GPL(vhost_dev_cleanup);
static int log_access_ok(void __user *log_base, u64 addr, unsigned long sz)
{
for (i = 0; i < d->nvqs; ++i) {
int ok;
+ bool log;
+
mutex_lock(&d->vqs[i]->mutex);
+ log = log_all || vhost_has_feature(d->vqs[i], VHOST_F_LOG_ALL);
/* If ring is inactive, will check when it's enabled. */
if (d->vqs[i]->private_data)
- ok = vq_memory_access_ok(d->vqs[i]->log_base, mem,
- log_all);
+ ok = vq_memory_access_ok(d->vqs[i]->log_base, mem, log);
else
ok = 1;
mutex_unlock(&d->vqs[i]->mutex);
return 1;
}
-static int vq_access_ok(struct vhost_dev *d, unsigned int num,
+static int vq_access_ok(struct vhost_virtqueue *vq, unsigned int num,
struct vring_desc __user *desc,
struct vring_avail __user *avail,
struct vring_used __user *used)
{
- size_t s = vhost_has_feature(d, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
+ size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
return access_ok(VERIFY_READ, desc, num * sizeof *desc) &&
access_ok(VERIFY_READ, avail,
sizeof *avail + num * sizeof *avail->ring + s) &&
/* Caller should have device mutex but not vq mutex */
int vhost_log_access_ok(struct vhost_dev *dev)
{
- struct vhost_memory *mp;
-
- mp = rcu_dereference_protected(dev->memory,
- lockdep_is_held(&dev->mutex));
- return memory_access_ok(dev, mp, 1);
+ return memory_access_ok(dev, dev->memory, 1);
}
+EXPORT_SYMBOL_GPL(vhost_log_access_ok);
/* Verify access for write logging. */
/* Caller should have vq mutex and device mutex */
-static int vq_log_access_ok(struct vhost_dev *d, struct vhost_virtqueue *vq,
+static int vq_log_access_ok(struct vhost_virtqueue *vq,
void __user *log_base)
{
- struct vhost_memory *mp;
- size_t s = vhost_has_feature(d, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
+ size_t s = vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX) ? 2 : 0;
- mp = rcu_dereference_protected(vq->dev->memory,
- lockdep_is_held(&vq->mutex));
- return vq_memory_access_ok(log_base, mp,
- vhost_has_feature(vq->dev, VHOST_F_LOG_ALL)) &&
+ return vq_memory_access_ok(log_base, vq->memory,
+ vhost_has_feature(vq, VHOST_F_LOG_ALL)) &&
(!vq->log_used || log_access_ok(log_base, vq->log_addr,
sizeof *vq->used +
vq->num * sizeof *vq->used->ring + s));
/* Caller should have vq mutex and device mutex */
int vhost_vq_access_ok(struct vhost_virtqueue *vq)
{
- return vq_access_ok(vq->dev, vq->num, vq->desc, vq->avail, vq->used) &&
- vq_log_access_ok(vq->dev, vq, vq->log_base);
+ return vq_access_ok(vq, vq->num, vq->desc, vq->avail, vq->used) &&
+ vq_log_access_ok(vq, vq->log_base);
+}
+EXPORT_SYMBOL_GPL(vhost_vq_access_ok);
+
+static int vhost_memory_reg_sort_cmp(const void *p1, const void *p2)
+{
+ const struct vhost_memory_region *r1 = p1, *r2 = p2;
+ if (r1->guest_phys_addr < r2->guest_phys_addr)
+ return 1;
+ if (r1->guest_phys_addr > r2->guest_phys_addr)
+ return -1;
+ return 0;
+}
+
+static void *vhost_kvzalloc(unsigned long size)
+{
+ void *n = kzalloc(size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
+
+ if (!n)
+ n = vzalloc(size);
+ return n;
}
static long vhost_set_memory(struct vhost_dev *d, struct vhost_memory __user *m)
{
struct vhost_memory mem, *newmem, *oldmem;
unsigned long size = offsetof(struct vhost_memory, regions);
+ int i;
if (copy_from_user(&mem, m, size))
return -EFAULT;
if (mem.padding)
return -EOPNOTSUPP;
- if (mem.nregions > VHOST_MEMORY_MAX_NREGIONS)
+ if (mem.nregions > max_mem_regions)
return -E2BIG;
- newmem = kmalloc(size + mem.nregions * sizeof *m->regions, GFP_KERNEL);
+ newmem = vhost_kvzalloc(size + mem.nregions * sizeof(*m->regions));
if (!newmem)
return -ENOMEM;
memcpy(newmem, &mem, size);
if (copy_from_user(newmem->regions, m->regions,
mem.nregions * sizeof *m->regions)) {
- kfree(newmem);
+ kvfree(newmem);
return -EFAULT;
}
+ sort(newmem->regions, newmem->nregions, sizeof(*newmem->regions),
+ vhost_memory_reg_sort_cmp, NULL);
- if (!memory_access_ok(d, newmem,
- vhost_has_feature(d, VHOST_F_LOG_ALL))) {
- kfree(newmem);
+ if (!memory_access_ok(d, newmem, 0)) {
+ kvfree(newmem);
return -EFAULT;
}
- oldmem = rcu_dereference_protected(d->memory,
- lockdep_is_held(&d->mutex));
- rcu_assign_pointer(d->memory, newmem);
- synchronize_rcu();
- kfree(oldmem);
+ oldmem = d->memory;
+ d->memory = newmem;
+
+ /* All memory accesses are done under some VQ mutex. */
+ for (i = 0; i < d->nvqs; ++i) {
+ mutex_lock(&d->vqs[i]->mutex);
+ d->vqs[i]->memory = newmem;
+ mutex_unlock(&d->vqs[i]->mutex);
+ }
+ kvfree(oldmem);
return 0;
}
r = -EFAULT;
break;
}
- if ((a.avail_user_addr & (sizeof *vq->avail->ring - 1)) ||
- (a.used_user_addr & (sizeof *vq->used->ring - 1)) ||
- (a.log_guest_addr & (sizeof *vq->used->ring - 1))) {
+
+ /* Make sure it's safe to cast pointers to vring types. */
+ BUILD_BUG_ON(__alignof__ *vq->avail > VRING_AVAIL_ALIGN_SIZE);
+ BUILD_BUG_ON(__alignof__ *vq->used > VRING_USED_ALIGN_SIZE);
+ if ((a.avail_user_addr & (VRING_AVAIL_ALIGN_SIZE - 1)) ||
+ (a.used_user_addr & (VRING_USED_ALIGN_SIZE - 1)) ||
+ (a.log_guest_addr & (VRING_USED_ALIGN_SIZE - 1))) {
r = -EINVAL;
break;
}
* If it is not, we don't as size might not have been setup.
* We will verify when backend is configured. */
if (vq->private_data) {
- if (!vq_access_ok(d, vq->num,
+ if (!vq_access_ok(vq, vq->num,
(void __user *)(unsigned long)a.desc_user_addr,
(void __user *)(unsigned long)a.avail_user_addr,
(void __user *)(unsigned long)a.used_user_addr)) {
} else
filep = eventfp;
break;
+ case VHOST_SET_VRING_ENDIAN:
+ r = vhost_set_vring_endian(vq, argp);
+ break;
+ case VHOST_GET_VRING_ENDIAN:
+ r = vhost_get_vring_endian(vq, idx, argp);
+ break;
default:
r = -ENOIOCTLCMD;
}
vhost_poll_flush(&vq->poll);
return r;
}
+EXPORT_SYMBOL_GPL(vhost_vring_ioctl);
/* Caller must have device mutex */
long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp)
vq = d->vqs[i];
mutex_lock(&vq->mutex);
/* If ring is inactive, will check when it's enabled. */
- if (vq->private_data && !vq_log_access_ok(d, vq, base))
+ if (vq->private_data && !vq_log_access_ok(vq, base))
r = -EFAULT;
else
vq->log_base = base;
done:
return r;
}
+EXPORT_SYMBOL_GPL(vhost_dev_ioctl);
static const struct vhost_memory_region *find_region(struct vhost_memory *mem,
__u64 addr, __u32 len)
{
- struct vhost_memory_region *reg;
- int i;
+ const struct vhost_memory_region *reg;
+ int start = 0, end = mem->nregions;
- /* linear search is not brilliant, but we really have on the order of 6
- * regions in practice */
- for (i = 0; i < mem->nregions; ++i) {
- reg = mem->regions + i;
- if (reg->guest_phys_addr <= addr &&
- reg->guest_phys_addr + reg->memory_size - 1 >= addr)
- return reg;
+ while (start < end) {
+ int slot = start + (end - start) / 2;
+ reg = mem->regions + slot;
+ if (addr >= reg->guest_phys_addr)
+ end = slot;
+ else
+ start = slot + 1;
}
+
+ reg = mem->regions + start;
+ if (addr >= reg->guest_phys_addr &&
+ reg->guest_phys_addr + reg->memory_size > addr)
+ return reg;
return NULL;
}
BUG();
return 0;
}
+EXPORT_SYMBOL_GPL(vhost_log_write);
static int vhost_update_used_flags(struct vhost_virtqueue *vq)
{
void __user *used;
- if (__put_user(vq->used_flags, &vq->used->flags) < 0)
+ if (__put_user(cpu_to_vhost16(vq, vq->used_flags), &vq->used->flags) < 0)
return -EFAULT;
if (unlikely(vq->log_used)) {
/* Make sure the flag is seen before log. */
static int vhost_update_avail_event(struct vhost_virtqueue *vq, u16 avail_event)
{
- if (__put_user(vq->avail_idx, vhost_avail_event(vq)))
+ if (__put_user(cpu_to_vhost16(vq, vq->avail_idx), vhost_avail_event(vq)))
return -EFAULT;
if (unlikely(vq->log_used)) {
void __user *used;
int vhost_init_used(struct vhost_virtqueue *vq)
{
+ __virtio16 last_used_idx;
int r;
- if (!vq->private_data)
+ if (!vq->private_data) {
+ vq->is_le = virtio_legacy_is_little_endian();
return 0;
+ }
+
+ vhost_init_is_le(vq);
r = vhost_update_used_flags(vq);
if (r)
return r;
vq->signalled_used_valid = false;
- return get_user(vq->last_used_idx, &vq->used->idx);
+ if (!access_ok(VERIFY_READ, &vq->used->idx, sizeof vq->used->idx))
+ return -EFAULT;
+ r = __get_user(last_used_idx, &vq->used->idx);
+ if (r)
+ return r;
+ vq->last_used_idx = vhost16_to_cpu(vq, last_used_idx);
+ return 0;
}
+EXPORT_SYMBOL_GPL(vhost_init_used);
-static int translate_desc(struct vhost_dev *dev, u64 addr, u32 len,
+static int translate_desc(struct vhost_virtqueue *vq, u64 addr, u32 len,
struct iovec iov[], int iov_size)
{
const struct vhost_memory_region *reg;
u64 s = 0;
int ret = 0;
- rcu_read_lock();
-
- mem = rcu_dereference(dev->memory);
+ mem = vq->memory;
while ((u64)len > s) {
u64 size;
if (unlikely(ret >= iov_size)) {
++ret;
}
- rcu_read_unlock();
return ret;
}
/* Each buffer in the virtqueues is actually a chain of descriptors. This
* function returns the next descriptor in the chain,
* or -1U if we're at the end. */
-static unsigned next_desc(struct vring_desc *desc)
+static unsigned next_desc(struct vhost_virtqueue *vq, struct vring_desc *desc)
{
unsigned int next;
/* If this descriptor says it doesn't chain, we're done. */
- if (!(desc->flags & VRING_DESC_F_NEXT))
+ if (!(desc->flags & cpu_to_vhost16(vq, VRING_DESC_F_NEXT)))
return -1U;
/* Check they're not leading us off end of descriptors. */
- next = desc->next;
+ next = vhost16_to_cpu(vq, desc->next);
/* Make sure compiler knows to grab that: we don't want it changing! */
/* We will use the result as an index in an array, so most
* architectures only need a compiler barrier here. */
return next;
}
-static int get_indirect(struct vhost_dev *dev, struct vhost_virtqueue *vq,
+static int get_indirect(struct vhost_virtqueue *vq,
struct iovec iov[], unsigned int iov_size,
unsigned int *out_num, unsigned int *in_num,
struct vhost_log *log, unsigned int *log_num,
{
struct vring_desc desc;
unsigned int i = 0, count, found = 0;
+ u32 len = vhost32_to_cpu(vq, indirect->len);
+ struct iov_iter from;
int ret;
/* Sanity check */
- if (unlikely(indirect->len % sizeof desc)) {
+ if (unlikely(len % sizeof desc)) {
vq_err(vq, "Invalid length in indirect descriptor: "
"len 0x%llx not multiple of 0x%zx\n",
- (unsigned long long)indirect->len,
+ (unsigned long long)len,
sizeof desc);
return -EINVAL;
}
- ret = translate_desc(dev, indirect->addr, indirect->len, vq->indirect,
+ ret = translate_desc(vq, vhost64_to_cpu(vq, indirect->addr), len, vq->indirect,
UIO_MAXIOV);
if (unlikely(ret < 0)) {
vq_err(vq, "Translation failure %d in indirect.\n", ret);
return ret;
}
+ iov_iter_init(&from, READ, vq->indirect, ret, len);
/* We will use the result as an address to read from, so most
* architectures only need a compiler barrier here. */
read_barrier_depends();
- count = indirect->len / sizeof desc;
+ count = len / sizeof desc;
/* Buffers are chained via a 16 bit next field, so
* we can have at most 2^16 of these. */
if (unlikely(count > USHRT_MAX + 1)) {
i, count);
return -EINVAL;
}
- if (unlikely(memcpy_fromiovec((unsigned char *)&desc,
- vq->indirect, sizeof desc))) {
+ if (unlikely(copy_from_iter(&desc, sizeof(desc), &from) !=
+ sizeof(desc))) {
vq_err(vq, "Failed indirect descriptor: idx %d, %zx\n",
- i, (size_t)indirect->addr + i * sizeof desc);
+ i, (size_t)vhost64_to_cpu(vq, indirect->addr) + i * sizeof desc);
return -EINVAL;
}
- if (unlikely(desc.flags & VRING_DESC_F_INDIRECT)) {
+ if (unlikely(desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_INDIRECT))) {
vq_err(vq, "Nested indirect descriptor: idx %d, %zx\n",
- i, (size_t)indirect->addr + i * sizeof desc);
+ i, (size_t)vhost64_to_cpu(vq, indirect->addr) + i * sizeof desc);
return -EINVAL;
}
- ret = translate_desc(dev, desc.addr, desc.len, iov + iov_count,
+ ret = translate_desc(vq, vhost64_to_cpu(vq, desc.addr),
+ vhost32_to_cpu(vq, desc.len), iov + iov_count,
iov_size - iov_count);
if (unlikely(ret < 0)) {
vq_err(vq, "Translation failure %d indirect idx %d\n",
return ret;
}
/* If this is an input descriptor, increment that count. */
- if (desc.flags & VRING_DESC_F_WRITE) {
+ if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_WRITE)) {
*in_num += ret;
if (unlikely(log)) {
- log[*log_num].addr = desc.addr;
- log[*log_num].len = desc.len;
+ log[*log_num].addr = vhost64_to_cpu(vq, desc.addr);
+ log[*log_num].len = vhost32_to_cpu(vq, desc.len);
++*log_num;
}
} else {
}
*out_num += ret;
}
- } while ((i = next_desc(&desc)) != -1);
+ } while ((i = next_desc(vq, &desc)) != -1);
return 0;
}
* This function returns the descriptor number found, or vq->num (which is
* never a valid descriptor number) if none was found. A negative code is
* returned on error. */
-int vhost_get_vq_desc(struct vhost_dev *dev, struct vhost_virtqueue *vq,
+int vhost_get_vq_desc(struct vhost_virtqueue *vq,
struct iovec iov[], unsigned int iov_size,
unsigned int *out_num, unsigned int *in_num,
struct vhost_log *log, unsigned int *log_num)
struct vring_desc desc;
unsigned int i, head, found = 0;
u16 last_avail_idx;
+ __virtio16 avail_idx;
+ __virtio16 ring_head;
int ret;
/* Check it isn't doing very strange things with descriptor numbers. */
last_avail_idx = vq->last_avail_idx;
- if (unlikely(__get_user(vq->avail_idx, &vq->avail->idx))) {
+ if (unlikely(__get_user(avail_idx, &vq->avail->idx))) {
vq_err(vq, "Failed to access avail idx at %p\n",
&vq->avail->idx);
return -EFAULT;
}
+ vq->avail_idx = vhost16_to_cpu(vq, avail_idx);
if (unlikely((u16)(vq->avail_idx - last_avail_idx) > vq->num)) {
vq_err(vq, "Guest moved used index from %u to %u",
/* Grab the next descriptor number they're advertising, and increment
* the index we've seen. */
- if (unlikely(__get_user(head,
- &vq->avail->ring[last_avail_idx % vq->num]))) {
+ if (unlikely(__get_user(ring_head,
+ &vq->avail->ring[last_avail_idx & (vq->num - 1)]))) {
vq_err(vq, "Failed to read head: idx %d address %p\n",
last_avail_idx,
&vq->avail->ring[last_avail_idx % vq->num]);
return -EFAULT;
}
+ head = vhost16_to_cpu(vq, ring_head);
+
/* If their number is silly, that's an error. */
if (unlikely(head >= vq->num)) {
vq_err(vq, "Guest says index %u > %u is available",
i, vq->desc + i);
return -EFAULT;
}
- if (desc.flags & VRING_DESC_F_INDIRECT) {
- ret = get_indirect(dev, vq, iov, iov_size,
+ if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_INDIRECT)) {
+ ret = get_indirect(vq, iov, iov_size,
out_num, in_num,
log, log_num, &desc);
if (unlikely(ret < 0)) {
continue;
}
- ret = translate_desc(dev, desc.addr, desc.len, iov + iov_count,
+ ret = translate_desc(vq, vhost64_to_cpu(vq, desc.addr),
+ vhost32_to_cpu(vq, desc.len), iov + iov_count,
iov_size - iov_count);
if (unlikely(ret < 0)) {
vq_err(vq, "Translation failure %d descriptor idx %d\n",
ret, i);
return ret;
}
- if (desc.flags & VRING_DESC_F_WRITE) {
+ if (desc.flags & cpu_to_vhost16(vq, VRING_DESC_F_WRITE)) {
/* If this is an input descriptor,
* increment that count. */
*in_num += ret;
if (unlikely(log)) {
- log[*log_num].addr = desc.addr;
- log[*log_num].len = desc.len;
+ log[*log_num].addr = vhost64_to_cpu(vq, desc.addr);
+ log[*log_num].len = vhost32_to_cpu(vq, desc.len);
++*log_num;
}
} else {
}
*out_num += ret;
}
- } while ((i = next_desc(&desc)) != -1);
+ } while ((i = next_desc(vq, &desc)) != -1);
/* On success, increment avail index. */
vq->last_avail_idx++;
BUG_ON(!(vq->used_flags & VRING_USED_F_NO_NOTIFY));
return head;
}
+EXPORT_SYMBOL_GPL(vhost_get_vq_desc);
/* Reverse the effect of vhost_get_vq_desc. Useful for error handling. */
void vhost_discard_vq_desc(struct vhost_virtqueue *vq, int n)
{
vq->last_avail_idx -= n;
}
+EXPORT_SYMBOL_GPL(vhost_discard_vq_desc);
/* After we've used one of their buffers, we tell them about it. We'll then
* want to notify the guest, using eventfd. */
int vhost_add_used(struct vhost_virtqueue *vq, unsigned int head, int len)
{
- struct vring_used_elem __user *used;
+ struct vring_used_elem heads = {
+ cpu_to_vhost32(vq, head),
+ cpu_to_vhost32(vq, len)
+ };
- /* The virtqueue contains a ring of used buffers. Get a pointer to the
- * next entry in that used ring. */
- used = &vq->used->ring[vq->last_used_idx % vq->num];
- if (__put_user(head, &used->id)) {
- vq_err(vq, "Failed to write used id");
- return -EFAULT;
- }
- if (__put_user(len, &used->len)) {
- vq_err(vq, "Failed to write used len");
- return -EFAULT;
- }
- /* Make sure buffer is written before we update index. */
- smp_wmb();
- if (__put_user(vq->last_used_idx + 1, &vq->used->idx)) {
- vq_err(vq, "Failed to increment used idx");
- return -EFAULT;
- }
- if (unlikely(vq->log_used)) {
- /* Make sure data is seen before log. */
- smp_wmb();
- /* Log used ring entry write. */
- log_write(vq->log_base,
- vq->log_addr +
- ((void __user *)used - (void __user *)vq->used),
- sizeof *used);
- /* Log used index update. */
- log_write(vq->log_base,
- vq->log_addr + offsetof(struct vring_used, idx),
- sizeof vq->used->idx);
- if (vq->log_ctx)
- eventfd_signal(vq->log_ctx, 1);
- }
- vq->last_used_idx++;
- /* If the driver never bothers to signal in a very long while,
- * used index might wrap around. If that happens, invalidate
- * signalled_used index we stored. TODO: make sure driver
- * signals at least once in 2^16 and remove this. */
- if (unlikely(vq->last_used_idx == vq->signalled_used))
- vq->signalled_used_valid = false;
- return 0;
+ return vhost_add_used_n(vq, &heads, 1);
}
+EXPORT_SYMBOL_GPL(vhost_add_used);
static int __vhost_add_used_n(struct vhost_virtqueue *vq,
struct vring_used_elem *heads,
u16 old, new;
int start;
- start = vq->last_used_idx % vq->num;
+ start = vq->last_used_idx & (vq->num - 1);
used = vq->used->ring + start;
- if (__copy_to_user(used, heads, count * sizeof *used)) {
+ if (count == 1) {
+ if (__put_user(heads[0].id, &used->id)) {
+ vq_err(vq, "Failed to write used id");
+ return -EFAULT;
+ }
+ if (__put_user(heads[0].len, &used->len)) {
+ vq_err(vq, "Failed to write used len");
+ return -EFAULT;
+ }
+ } else if (__copy_to_user(used, heads, count * sizeof *used)) {
vq_err(vq, "Failed to write used");
return -EFAULT;
}
{
int start, n, r;
- start = vq->last_used_idx % vq->num;
+ start = vq->last_used_idx & (vq->num - 1);
n = vq->num - start;
if (n < count) {
r = __vhost_add_used_n(vq, heads, n);
/* Make sure buffer is written before we update index. */
smp_wmb();
- if (put_user(vq->last_used_idx, &vq->used->idx)) {
+ if (__put_user(cpu_to_vhost16(vq, vq->last_used_idx), &vq->used->idx)) {
vq_err(vq, "Failed to increment used idx");
return -EFAULT;
}
}
return r;
}
+EXPORT_SYMBOL_GPL(vhost_add_used_n);
static bool vhost_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
{
- __u16 old, new, event;
+ __u16 old, new;
+ __virtio16 event;
bool v;
/* Flush out used index updates. This is paired
* with the barrier that the Guest executes when enabling
* interrupts. */
smp_mb();
- if (vhost_has_feature(dev, VIRTIO_F_NOTIFY_ON_EMPTY) &&
+ if (vhost_has_feature(vq, VIRTIO_F_NOTIFY_ON_EMPTY) &&
unlikely(vq->avail_idx == vq->last_avail_idx))
return true;
- if (!vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
- __u16 flags;
+ if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) {
+ __virtio16 flags;
if (__get_user(flags, &vq->avail->flags)) {
vq_err(vq, "Failed to get flags");
return true;
}
- return !(flags & VRING_AVAIL_F_NO_INTERRUPT);
+ return !(flags & cpu_to_vhost16(vq, VRING_AVAIL_F_NO_INTERRUPT));
}
old = vq->signalled_used;
v = vq->signalled_used_valid;
if (unlikely(!v))
return true;
- if (get_user(event, vhost_used_event(vq))) {
+ if (__get_user(event, vhost_used_event(vq))) {
vq_err(vq, "Failed to get used event idx");
return true;
}
- return vring_need_event(event, new, old);
+ return vring_need_event(vhost16_to_cpu(vq, event), new, old);
}
/* This actually signals the guest, using eventfd. */
if (vq->call_ctx && vhost_notify(dev, vq))
eventfd_signal(vq->call_ctx, 1);
}
+EXPORT_SYMBOL_GPL(vhost_signal);
/* And here's the combo meal deal. Supersize me! */
void vhost_add_used_and_signal(struct vhost_dev *dev,
vhost_add_used(vq, head, len);
vhost_signal(dev, vq);
}
+EXPORT_SYMBOL_GPL(vhost_add_used_and_signal);
/* multi-buffer version of vhost_add_used_and_signal */
void vhost_add_used_and_signal_n(struct vhost_dev *dev,
vhost_add_used_n(vq, heads, count);
vhost_signal(dev, vq);
}
+EXPORT_SYMBOL_GPL(vhost_add_used_and_signal_n);
/* OK, now we need to know about added descriptors. */
bool vhost_enable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
{
- u16 avail_idx;
+ __virtio16 avail_idx;
int r;
if (!(vq->used_flags & VRING_USED_F_NO_NOTIFY))
return false;
vq->used_flags &= ~VRING_USED_F_NO_NOTIFY;
- if (!vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
+ if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) {
r = vhost_update_used_flags(vq);
if (r) {
vq_err(vq, "Failed to enable notification at %p: %d\n",
return false;
}
- return avail_idx != vq->avail_idx;
+ return vhost16_to_cpu(vq, avail_idx) != vq->avail_idx;
}
+EXPORT_SYMBOL_GPL(vhost_enable_notify);
/* We don't need to be notified again. */
void vhost_disable_notify(struct vhost_dev *dev, struct vhost_virtqueue *vq)
if (vq->used_flags & VRING_USED_F_NO_NOTIFY)
return;
vq->used_flags |= VRING_USED_F_NO_NOTIFY;
- if (!vhost_has_feature(dev, VIRTIO_RING_F_EVENT_IDX)) {
+ if (!vhost_has_feature(vq, VIRTIO_RING_F_EVENT_IDX)) {
r = vhost_update_used_flags(vq);
if (r)
vq_err(vq, "Failed to enable notification at %p: %d\n",
&vq->used->flags, r);
}
}
+EXPORT_SYMBOL_GPL(vhost_disable_notify);
+
+static int __init vhost_init(void)
+{
+ return 0;
+}
+
+static void __exit vhost_exit(void)
+{
+}
+
+module_init(vhost_init);
+module_exit(vhost_exit);
+
+MODULE_VERSION("0.0.1");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Michael S. Tsirkin");
+MODULE_DESCRIPTION("Host kernel accelerator for virtio");