From ccc9d90a9a8b5c4ad7e9708ec41f75ff9e98d61d Mon Sep 17 00:00:00 2001 From: Wei Liu Date: Fri, 3 Apr 2015 14:44:59 +0800 Subject: xenbus_client: Extend interface to support multi-page ring Originally Xen PV drivers only use single-page ring to pass along information. This might limit the throughput between frontend and backend. The patch extends Xenbus driver to support multi-page ring, which in general should improve throughput if ring is the bottleneck. Changes to various frontend / backend to adapt to the new interface are also included. Affected Xen drivers: * blkfront/back * netfront/back * pcifront/back * scsifront/back * vtpmfront The interface is documented, as before, in xenbus_client.c. Signed-off-by: Wei Liu Signed-off-by: Paul Durrant Signed-off-by: Bob Liu Cc: Konrad Wilk Cc: Boris Ostrovsky Signed-off-by: David Vrabel --- include/xen/xenbus.h | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) (limited to 'include/xen') diff --git a/include/xen/xenbus.h b/include/xen/xenbus.h index b0f1c9e5d687..289c0b5f08fe 100644 --- a/include/xen/xenbus.h +++ b/include/xen/xenbus.h @@ -46,6 +46,10 @@ #include #include +#define XENBUS_MAX_RING_PAGE_ORDER 4 +#define XENBUS_MAX_RING_PAGES (1U << XENBUS_MAX_RING_PAGE_ORDER) +#define INVALID_GRANT_HANDLE (~0U) + /* Register callback to watch this node. */ struct xenbus_watch { @@ -199,15 +203,19 @@ int xenbus_watch_pathfmt(struct xenbus_device *dev, struct xenbus_watch *watch, const char *pathfmt, ...); int xenbus_switch_state(struct xenbus_device *dev, enum xenbus_state new_state); -int xenbus_grant_ring(struct xenbus_device *dev, unsigned long ring_mfn); -int xenbus_map_ring_valloc(struct xenbus_device *dev, - int gnt_ref, void **vaddr); -int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref, - grant_handle_t *handle, void *vaddr); +int xenbus_grant_ring(struct xenbus_device *dev, void *vaddr, + unsigned int nr_pages, grant_ref_t *grefs); +int xenbus_map_ring_valloc(struct xenbus_device *dev, grant_ref_t *gnt_refs, + unsigned int nr_grefs, void **vaddr); +int xenbus_map_ring(struct xenbus_device *dev, + grant_ref_t *gnt_refs, unsigned int nr_grefs, + grant_handle_t *handles, unsigned long *vaddrs, + bool *leaked); int xenbus_unmap_ring_vfree(struct xenbus_device *dev, void *vaddr); int xenbus_unmap_ring(struct xenbus_device *dev, - grant_handle_t handle, void *vaddr); + grant_handle_t *handles, unsigned int nr_handles, + unsigned long *vaddrs); int xenbus_alloc_evtchn(struct xenbus_device *dev, int *port); int xenbus_free_evtchn(struct xenbus_device *dev, int port); -- cgit v1.2.3