On Thu, Aug 24, 2017 at 08:27:20PM +0100, Dr. David Alan Gilbert (git) wrote:
> From: "Dr. David Alan Gilbert" <dgilb...@redhat.com>
>
> Register a waker function in vhost-user code to be notified when
> pages arrive or requests to previously mapped pages get requested.
>
> Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> ---
> hw/virtio/trace-events | 3 +++
> hw/virtio/vhost-user.c | 26 ++++++++++++++++++++++++++
> 2 files changed, 29 insertions(+)
>
> diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
> index f7d4b831fe..adebf6dc6b 100644
> --- a/hw/virtio/trace-events
> +++ b/hw/virtio/trace-events
> @@ -7,6 +7,9 @@ vhost_user_postcopy_fault_handler_found(int i, uint64_t
> region_offset, uint64_t
> vhost_user_postcopy_listen(void) ""
> vhost_user_set_mem_table_postcopy(uint64_t client_addr, uint64_t qhva, int
> reply_i, int region_i) "client:0x%"PRIx64" for hva: 0x%"PRIx64" reply %d
> region %d"
> vhost_user_set_mem_table_withfd(int index, const char *name, uint64_t
> memory_size, uint64_t guest_phys_addr, uint64_t userspace_addr, uint64_t
> offset) "%d:%s: size:0x%"PRIx64" GPA:0x%"PRIx64" QVA/userspace:0x%"PRIx64" RB
> offset:0x%"PRIx64
> +vhost_user_postcopy_waker(const char *rb, uint64_t rb_offset) "%s +
> 0x%"PRIx64
> +vhost_user_postcopy_waker_found(uint64_t client_addr) "0x%"PRIx64
> +vhost_user_postcopy_waker_nomatch(const char *rb, uint64_t rb_offset) "%s +
> 0x%"PRIx64
>
> # hw/virtio/virtio.c
> virtqueue_alloc_element(void *elem, size_t sz, unsigned in_num, unsigned
> out_num) "elem %p size %zd in_num %u out_num %u"
> diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
> index 2897ff70b3..3bff33a1a6 100644
> --- a/hw/virtio/vhost-user.c
> +++ b/hw/virtio/vhost-user.c
> @@ -847,6 +847,31 @@ static int vhost_user_postcopy_fault_handler(struct
> PostCopyFD *pcfd,
> return -1;
> }
>
> +static int vhost_user_postcopy_waker(struct PostCopyFD *pcfd, RAMBlock *rb,
> + uint64_t offset)
> +{
> + struct vhost_dev *dev = pcfd->data;
> + struct vhost_user *u = dev->opaque;
> + int i;
> +
> + trace_vhost_user_postcopy_waker(qemu_ram_get_idstr(rb), offset);
> + /* Translate the offset into an address in the clients address space */
> + for (i = 0; i < MIN(dev->mem->nregions, u->region_rb_len); i++) {
> + if (u->region_rb[i] == rb &&
> + offset >= u->region_rb_offset[i] &&
> + offset < (u->region_rb_offset[i] +
> + dev->mem->regions[i].memory_size)) {
Just curious: checks against offset should only be for safety, right?
Is there valid case that even rb is correct but the offset gets out of
the range of that RAMBlock?
> + uint64_t client_addr = (offset - u->region_rb_offset[i]) +
> + u->postcopy_client_bases[i];
> + trace_vhost_user_postcopy_waker_found(client_addr);
> + return postcopy_wake_shared(pcfd, client_addr, rb);
> + }
> + }
> +
> + trace_vhost_user_postcopy_waker_nomatch(qemu_ram_get_idstr(rb), offset);
> + return 0;
> +}
> +
> /*
> * Called at the start of an inbound postcopy on reception of the
> * 'advise' command.
> @@ -892,6 +917,7 @@ static int vhost_user_postcopy_advise(struct vhost_dev
> *dev, Error **errp)
> u->postcopy_fd.fd = ufd;
> u->postcopy_fd.data = dev;
> u->postcopy_fd.handler = vhost_user_postcopy_fault_handler;
> + u->postcopy_fd.waker = vhost_user_postcopy_waker;
> u->postcopy_fd.idstr = "vhost-user"; /* Need to find unique name */
> postcopy_register_shared_ufd(&u->postcopy_fd);
> return 0;
> --
> 2.13.5
>
--
Peter Xu
