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authorLinus Torvalds <torvalds@linux-foundation.org>2020-06-10 23:42:09 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2020-06-10 23:42:09 +0300
commit09102704c67457c6cdea6c0394c34843484a852c (patch)
treec4faeb56ff6c94d50b56da17969b88b27c19eae5 /drivers/vhost/vhost.c
parent84fc461db99b2dc19e019c0a97725a3653687981 (diff)
parent044e4b09223039e571e6ec540e25552054208765 (diff)
downloadlinux-09102704c67457c6cdea6c0394c34843484a852c.tar.xz
Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio updates from Michael Tsirkin: - virtio-mem: paravirtualized memory hotplug - support doorbell mapping for vdpa - config interrupt support in ifc - fixes all over the place * tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (40 commits) vhost/test: fix up after API change virtio_mem: convert device block size into 64bit virtio-mem: drop unnecessary initialization ifcvf: implement config interrupt in IFCVF vhost: replace -1 with VHOST_FILE_UNBIND in ioctls vhost_vdpa: Support config interrupt in vdpa ifcvf: ignore continuous setting same status value virtio-mem: Don't rely on implicit compiler padding for requests virtio-mem: Try to unplug the complete online memory block first virtio-mem: Use -ETXTBSY as error code if the device is busy virtio-mem: Unplug subblocks right-to-left virtio-mem: Drop manual check for already present memory virtio-mem: Add parent resource for all added "System RAM" virtio-mem: Better retry handling virtio-mem: Offline and remove completely unplugged memory blocks mm/memory_hotplug: Introduce offline_and_remove_memory() virtio-mem: Allow to offline partially unplugged memory blocks mm: Allow to offline unmovable PageOffline() pages via MEM_GOING_OFFLINE virtio-mem: Paravirtualized memory hotunplug part 2 virtio-mem: Paravirtualized memory hotunplug part 1 ...
Diffstat (limited to 'drivers/vhost/vhost.c')
-rw-r--r--drivers/vhost/vhost.c98
1 files changed, 68 insertions, 30 deletions
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 596132a96cd5..062595ee1f83 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -166,11 +166,16 @@ static int vhost_poll_wakeup(wait_queue_entry_t *wait, unsigned mode, int sync,
void *key)
{
struct vhost_poll *poll = container_of(wait, struct vhost_poll, wait);
+ struct vhost_work *work = &poll->work;
if (!(key_to_poll(key) & poll->mask))
return 0;
- vhost_poll_queue(poll);
+ if (!poll->dev->use_worker)
+ work->fn(work);
+ else
+ vhost_poll_queue(poll);
+
return 0;
}
@@ -454,6 +459,7 @@ static size_t vhost_get_desc_size(struct vhost_virtqueue *vq,
void vhost_dev_init(struct vhost_dev *dev,
struct vhost_virtqueue **vqs, int nvqs,
int iov_limit, int weight, int byte_weight,
+ bool use_worker,
int (*msg_handler)(struct vhost_dev *dev,
struct vhost_iotlb_msg *msg))
{
@@ -471,6 +477,7 @@ void vhost_dev_init(struct vhost_dev *dev,
dev->iov_limit = iov_limit;
dev->weight = weight;
dev->byte_weight = byte_weight;
+ dev->use_worker = use_worker;
dev->msg_handler = msg_handler;
init_llist_head(&dev->work_list);
init_waitqueue_head(&dev->wait);
@@ -534,6 +541,36 @@ bool vhost_dev_has_owner(struct vhost_dev *dev)
}
EXPORT_SYMBOL_GPL(vhost_dev_has_owner);
+static void vhost_attach_mm(struct vhost_dev *dev)
+{
+ /* No owner, become one */
+ if (dev->use_worker) {
+ dev->mm = get_task_mm(current);
+ } else {
+ /* vDPA device does not use worker thead, so there's
+ * no need to hold the address space for mm. This help
+ * to avoid deadlock in the case of mmap() which may
+ * held the refcnt of the file and depends on release
+ * method to remove vma.
+ */
+ dev->mm = current->mm;
+ mmgrab(dev->mm);
+ }
+}
+
+static void vhost_detach_mm(struct vhost_dev *dev)
+{
+ if (!dev->mm)
+ return;
+
+ if (dev->use_worker)
+ mmput(dev->mm);
+ else
+ mmdrop(dev->mm);
+
+ dev->mm = NULL;
+}
+
/* Caller should have device mutex */
long vhost_dev_set_owner(struct vhost_dev *dev)
{
@@ -546,21 +583,24 @@ long vhost_dev_set_owner(struct vhost_dev *dev)
goto err_mm;
}
- /* No owner, become one */
- dev->mm = get_task_mm(current);
+ vhost_attach_mm(dev);
+
dev->kcov_handle = kcov_common_handle();
- worker = kthread_create(vhost_worker, dev, "vhost-%d", current->pid);
- if (IS_ERR(worker)) {
- err = PTR_ERR(worker);
- goto err_worker;
- }
+ if (dev->use_worker) {
+ worker = kthread_create(vhost_worker, dev,
+ "vhost-%d", current->pid);
+ if (IS_ERR(worker)) {
+ err = PTR_ERR(worker);
+ goto err_worker;
+ }
- dev->worker = worker;
- wake_up_process(worker); /* avoid contributing to loadavg */
+ dev->worker = worker;
+ wake_up_process(worker); /* avoid contributing to loadavg */
- err = vhost_attach_cgroups(dev);
- if (err)
- goto err_cgroup;
+ err = vhost_attach_cgroups(dev);
+ if (err)
+ goto err_cgroup;
+ }
err = vhost_dev_alloc_iovecs(dev);
if (err)
@@ -568,12 +608,12 @@ long vhost_dev_set_owner(struct vhost_dev *dev)
return 0;
err_cgroup:
- kthread_stop(worker);
- dev->worker = NULL;
+ if (dev->worker) {
+ kthread_stop(dev->worker);
+ dev->worker = NULL;
+ }
err_worker:
- if (dev->mm)
- mmput(dev->mm);
- dev->mm = NULL;
+ vhost_detach_mm(dev);
dev->kcov_handle = 0;
err_mm:
return err;
@@ -670,9 +710,7 @@ void vhost_dev_cleanup(struct vhost_dev *dev)
dev->worker = NULL;
dev->kcov_handle = 0;
}
- if (dev->mm)
- mmput(dev->mm);
- dev->mm = NULL;
+ vhost_detach_mm(dev);
}
EXPORT_SYMBOL_GPL(vhost_dev_cleanup);
@@ -882,7 +920,7 @@ static inline void __user *__vhost_get_user(struct vhost_virtqueue *vq,
#define vhost_put_user(vq, x, ptr) \
({ \
- int ret = -EFAULT; \
+ int ret; \
if (!vq->iotlb) { \
ret = __put_user(x, ptr); \
} else { \
@@ -1244,9 +1282,9 @@ static int vhost_iotlb_miss(struct vhost_virtqueue *vq, u64 iova, int access)
}
static bool 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)
+ vring_desc_t __user *desc,
+ vring_avail_t __user *avail,
+ vring_used_t __user *used)
{
return access_ok(desc, vhost_get_desc_size(vq, num)) &&
@@ -1574,7 +1612,7 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg
r = -EFAULT;
break;
}
- eventfp = f.fd == -1 ? NULL : eventfd_fget(f.fd);
+ eventfp = f.fd == VHOST_FILE_UNBIND ? NULL : eventfd_fget(f.fd);
if (IS_ERR(eventfp)) {
r = PTR_ERR(eventfp);
break;
@@ -1590,7 +1628,7 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg
r = -EFAULT;
break;
}
- ctx = f.fd == -1 ? NULL : eventfd_ctx_fdget(f.fd);
+ ctx = f.fd == VHOST_FILE_UNBIND ? NULL : eventfd_ctx_fdget(f.fd);
if (IS_ERR(ctx)) {
r = PTR_ERR(ctx);
break;
@@ -1602,7 +1640,7 @@ long vhost_vring_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *arg
r = -EFAULT;
break;
}
- ctx = f.fd == -1 ? NULL : eventfd_ctx_fdget(f.fd);
+ ctx = f.fd == VHOST_FILE_UNBIND ? NULL : eventfd_ctx_fdget(f.fd);
if (IS_ERR(ctx)) {
r = PTR_ERR(ctx);
break;
@@ -1727,7 +1765,7 @@ long vhost_dev_ioctl(struct vhost_dev *d, unsigned int ioctl, void __user *argp)
r = get_user(fd, (int __user *)argp);
if (r < 0)
break;
- ctx = fd == -1 ? NULL : eventfd_ctx_fdget(fd);
+ ctx = fd == VHOST_FILE_UNBIND ? NULL : eventfd_ctx_fdget(fd);
if (IS_ERR(ctx)) {
r = PTR_ERR(ctx);
break;
@@ -2300,7 +2338,7 @@ static int __vhost_add_used_n(struct vhost_virtqueue *vq,
struct vring_used_elem *heads,
unsigned count)
{
- struct vring_used_elem __user *used;
+ vring_used_elem_t __user *used;
u16 old, new;
int start;