gntdev-common.h

  1/* SPDX-License-Identifier: GPL-2.0 */
  2
  3/*
  4 * Common functionality of grant device.
  5 *
  6 * Copyright (c) 2006-2007, D G Murray.
  7 *           (c) 2009 Gerd Hoffmann <kraxel@redhat.com>
  8 *           (c) 2018 Oleksandr Andrushchenko, EPAM Systems Inc.
  9 */
 10
 11#ifndef _GNTDEV_COMMON_H
 12#define _GNTDEV_COMMON_H
 13
 14#include <linux/mm.h>
 15#include <linux/mman.h>
 16#include <linux/mmu_notifier.h>
 17#include <linux/types.h>
 18#include <xen/interface/event_channel.h>
 19#include <xen/grant_table.h>
 20
 21struct gntdev_dmabuf_priv;
 22
 23struct gntdev_priv {
 24	/* Maps with visible offsets in the file descriptor. */
 25	struct list_head maps;
 26	/* lock protects maps and freeable_maps. */
 27	struct mutex lock;
 28
 29	/* Free instances of struct gntdev_copy_batch. */
 30	struct gntdev_copy_batch *batch;
 31	struct mutex batch_lock;
 32
 33#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
 34	/* Device for which DMA memory is allocated. */
 35	struct device *dma_dev;
 36#endif
 37
 38#ifdef CONFIG_XEN_GNTDEV_DMABUF
 39	struct gntdev_dmabuf_priv *dmabuf_priv;
 40#endif
 41};
 42
 43struct gntdev_unmap_notify {
 44	int flags;
 45	/* Address relative to the start of the gntdev_grant_map. */
 46	int addr;
 47	evtchn_port_t event;
 48};
 49
 50struct gntdev_grant_map {
 51	atomic_t in_use;
 52	struct mmu_interval_notifier notifier;
 53	bool notifier_init;
 54	struct list_head next;
 55	int index;
 56	int count;
 57	int flags;
 58	refcount_t users;
 59	struct gntdev_unmap_notify notify;
 60	struct ioctl_gntdev_grant_ref *grants;
 61	struct gnttab_map_grant_ref   *map_ops;
 62	struct gnttab_unmap_grant_ref *unmap_ops;
 63	struct gnttab_map_grant_ref   *kmap_ops;
 64	struct gnttab_unmap_grant_ref *kunmap_ops;
 65	bool *being_removed;
 66	struct page **pages;
 67	unsigned long pages_vm_start;
 68
 69#ifdef CONFIG_XEN_GRANT_DMA_ALLOC
 70	/*
 71	 * If dmabuf_vaddr is not NULL then this mapping is backed by DMA
 72	 * capable memory.
 73	 */
 74
 75	struct device *dma_dev;
 76	/* Flags used to create this DMA buffer: GNTDEV_DMA_FLAG_XXX. */
 77	int dma_flags;
 78	void *dma_vaddr;
 79	dma_addr_t dma_bus_addr;
 80	/* Needed to avoid allocation in gnttab_dma_free_pages(). */
 81	xen_pfn_t *frames;
 82#endif
 83
 84	/* Number of live grants */
 85	atomic_t live_grants;
 86	/* Needed to avoid allocation in __unmap_grant_pages */
 87	struct gntab_unmap_queue_data unmap_data;
 88};
 89
 90struct gntdev_grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count,
 91					  int dma_flags);
 92
 93void gntdev_add_map(struct gntdev_priv *priv, struct gntdev_grant_map *add);
 94
 95void gntdev_put_map(struct gntdev_priv *priv, struct gntdev_grant_map *map);
 96
 97bool gntdev_test_page_count(unsigned int count);
 98
 99int gntdev_map_grant_pages(struct gntdev_grant_map *map);
100
101#endif