ib_umem_odp.h

 1/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
 2/*
 3 * Copyright (c) 2014 Mellanox Technologies. All rights reserved.
 4 */
 5
 6#ifndef IB_UMEM_ODP_H
 7#define IB_UMEM_ODP_H
 8
 9#include <rdma/ib_umem.h>
10#include <rdma/ib_verbs.h>
11#include <linux/hmm-dma.h>
12
13struct ib_umem_odp {
14	struct ib_umem umem;
15	struct mmu_interval_notifier notifier;
16	struct pid *tgid;
17
18	struct hmm_dma_map map;
19
20	/*
21	 * The umem_mutex protects the page_list field of an ODP
22	 * umem, allowing only a single thread to map/unmap pages. The mutex
23	 * also protects access to the mmu notifier counters.
24	 */
25	struct mutex		umem_mutex;
26	void			*private; /* for the HW driver to use. */
27
28	int npages;
29
30	/*
31	 * An implicit odp umem cannot be DMA mapped, has 0 length, and serves
32	 * only as an anchor for the driver to hold onto the per_mm. FIXME:
33	 * This should be removed and drivers should work with the per_mm
34	 * directly.
35	 */
36	bool is_implicit_odp;
37
38	unsigned int		page_shift;
39};
40
41static inline struct ib_umem_odp *to_ib_umem_odp(struct ib_umem *umem)
42{
43	return container_of(umem, struct ib_umem_odp, umem);
44}
45
46/* Returns the first page of an ODP umem. */
47static inline unsigned long ib_umem_start(struct ib_umem_odp *umem_odp)
48{
49	return umem_odp->notifier.interval_tree.start;
50}
51
52/* Returns the address of the page after the last one of an ODP umem. */
53static inline unsigned long ib_umem_end(struct ib_umem_odp *umem_odp)
54{
55	return umem_odp->notifier.interval_tree.last + 1;
56}
57
58static inline size_t ib_umem_odp_num_pages(struct ib_umem_odp *umem_odp)
59{
60	return (ib_umem_end(umem_odp) - ib_umem_start(umem_odp)) >>
61	       umem_odp->page_shift;
62}
63
64#ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
65
66struct ib_umem_odp *
67ib_umem_odp_get(struct ib_device *device, unsigned long addr, size_t size,
68		int access, const struct mmu_interval_notifier_ops *ops);
69struct ib_umem_odp *ib_umem_odp_alloc_implicit(struct ib_device *device,
70					       int access);
71struct ib_umem_odp *
72ib_umem_odp_alloc_child(struct ib_umem_odp *root_umem, unsigned long addr,
73			size_t size,
74			const struct mmu_interval_notifier_ops *ops);
75void ib_umem_odp_release(struct ib_umem_odp *umem_odp);
76
77int ib_umem_odp_map_dma_and_lock(struct ib_umem_odp *umem_odp, u64 start_offset,
78				 u64 bcnt, u64 access_mask, bool fault);
79
80void ib_umem_odp_unmap_dma_pages(struct ib_umem_odp *umem_odp, u64 start_offset,
81				 u64 bound);
82
83#else /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */
84
85static inline struct ib_umem_odp *
86ib_umem_odp_get(struct ib_device *device, unsigned long addr, size_t size,
87		int access, const struct mmu_interval_notifier_ops *ops)
88{
89	return ERR_PTR(-EINVAL);
90}
91
92static inline void ib_umem_odp_release(struct ib_umem_odp *umem_odp) {}
93
94#endif /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */
95
96#endif /* IB_UMEM_ODP_H */