Hi
On Thu, Mar 8, 2018 at 8:58 PM, Dr. David Alan Gilbert (git)
<dgilb...@redhat.com> wrote:
> From: "Dr. David Alan Gilbert" <dgilb...@redhat.com>
>
> Resolve fault addresses read off the clients UFD into RAMBlock
> and offset, and call back to the postcopy code to ask for the page.
>
> Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
> Reviewed-by: Peter Xu <pet...@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lur...@redhat.com>
> ---
> hw/virtio/trace-events | 3 +++
> hw/virtio/vhost-user.c | 31 ++++++++++++++++++++++++++++++-
> 2 files changed, 33 insertions(+), 1 deletion(-)
>
> diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events
> index d7e9e1084b..3afd12cfea 100644
> --- a/hw/virtio/trace-events
> +++ b/hw/virtio/trace-events
> @@ -7,6 +7,9 @@ vhost_region_add_section_abut(const char *name, uint64_t
> new_size) "%s: 0x%"PRIx
> vhost_section(const char *name, int r) "%s:%d"
>
> # hw/virtio/vhost-user.c
> +vhost_user_postcopy_fault_handler(const char *name, uint64_t fault_address,
> int nregions) "%s: @0x%"PRIx64" nregions:%d"
> +vhost_user_postcopy_fault_handler_loop(int i, uint64_t client_base, uint64_t
> size) "%d: client 0x%"PRIx64" +0x%"PRIx64
> +vhost_user_postcopy_fault_handler_found(int i, uint64_t region_offset,
> uint64_t rb_offset) "%d: region_offset: 0x%"PRIx64" rb_offset:0x%"PRIx64
> 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
> diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
> index fd65616961..e19b9ef9cf 100644
> --- a/hw/virtio/vhost-user.c
> +++ b/hw/virtio/vhost-user.c
> @@ -26,6 +26,7 @@
> #include <sys/socket.h>
> #include <sys/un.h>
> #include <linux/vhost.h>
> +#include <linux/userfaultfd.h>
>
> #define VHOST_MEMORY_MAX_NREGIONS 8
> #define VHOST_USER_F_PROTOCOL_FEATURES 30
> @@ -974,7 +975,35 @@ out:
> static int vhost_user_postcopy_fault_handler(struct PostCopyFD *pcfd,
> void *ufd)
> {
> - return 0;
> + struct vhost_dev *dev = pcfd->data;
> + struct vhost_user *u = dev->opaque;
> + struct uffd_msg *msg = ufd;
> + uint64_t faultaddr = msg->arg.pagefault.address;
> + RAMBlock *rb = NULL;
> + uint64_t rb_offset;
> + int i;
> +
> + trace_vhost_user_postcopy_fault_handler(pcfd->idstr, faultaddr,
> + dev->mem->nregions);
> + for (i = 0; i < MIN(dev->mem->nregions, u->region_rb_len); i++) {
> + trace_vhost_user_postcopy_fault_handler_loop(i,
> + u->postcopy_client_bases[i],
> dev->mem->regions[i].memory_size);
> + if (faultaddr >= u->postcopy_client_bases[i]) {
> + /* Ofset of the fault address in the vhost region */
> + uint64_t region_offset = faultaddr - u->postcopy_client_bases[i];
> + if (region_offset < dev->mem->regions[i].memory_size) {
> + rb_offset = region_offset + u->region_rb_offset[i];
It may be worth to add an assert (i < u->region_rb_len) ?
> + trace_vhost_user_postcopy_fault_handler_found(i,
> + region_offset, rb_offset);
> + rb = u->region_rb[i];
> + return postcopy_request_shared_page(pcfd, rb, faultaddr,
> + rb_offset);
> + }
> + }
> + }
> + error_report("%s: Failed to find region for fault %" PRIx64,
> + __func__, faultaddr);
> + return -1;
> }
>
> /*
> --
> 2.14.3
>
>
--
Marc-André Lureau
