1 /* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
3 * Copyright (c) 2014 Mellanox Technologies. All rights reserved.
9 #include <rdma/ib_umem.h>
10 #include <rdma/ib_verbs.h>
14 struct mmu_interval_notifier notifier;
18 * An array of the pages included in the on-demand paging umem.
19 * Indices of pages that are currently not mapped into the device will
22 struct page **page_list;
24 * An array of the same size as page_list, with DMA addresses mapped
25 * for pages the pages in page_list. The lower two bits designate
26 * access permissions. See ODP_READ_ALLOWED_BIT and
27 * ODP_WRITE_ALLOWED_BIT.
31 * The umem_mutex protects the page_list and dma_list fields of an ODP
32 * umem, allowing only a single thread to map/unmap pages. The mutex
33 * also protects access to the mmu notifier counters.
35 struct mutex umem_mutex;
36 void *private; /* for the HW driver to use. */
41 * An implicit odp umem cannot be DMA mapped, has 0 length, and serves
42 * only as an anchor for the driver to hold onto the per_mm. FIXME:
43 * This should be removed and drivers should work with the per_mm
48 unsigned int page_shift;
51 static inline struct ib_umem_odp *to_ib_umem_odp(struct ib_umem *umem)
53 return container_of(umem, struct ib_umem_odp, umem);
56 /* Returns the first page of an ODP umem. */
57 static inline unsigned long ib_umem_start(struct ib_umem_odp *umem_odp)
59 return umem_odp->notifier.interval_tree.start;
62 /* Returns the address of the page after the last one of an ODP umem. */
63 static inline unsigned long ib_umem_end(struct ib_umem_odp *umem_odp)
65 return umem_odp->notifier.interval_tree.last + 1;
68 static inline size_t ib_umem_odp_num_pages(struct ib_umem_odp *umem_odp)
70 return (ib_umem_end(umem_odp) - ib_umem_start(umem_odp)) >>
75 * The lower 2 bits of the DMA address signal the R/W permissions for
76 * the entry. To upgrade the permissions, provide the appropriate
77 * bitmask to the map_dma_pages function.
79 * Be aware that upgrading a mapped address might result in change of
80 * the DMA address for the page.
82 #define ODP_READ_ALLOWED_BIT (1<<0ULL)
83 #define ODP_WRITE_ALLOWED_BIT (1<<1ULL)
85 #define ODP_DMA_ADDR_MASK (~(ODP_READ_ALLOWED_BIT | ODP_WRITE_ALLOWED_BIT))
87 #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
90 ib_umem_odp_get(struct ib_device *device, unsigned long addr, size_t size,
91 int access, const struct mmu_interval_notifier_ops *ops);
92 struct ib_umem_odp *ib_umem_odp_alloc_implicit(struct ib_device *device,
95 ib_umem_odp_alloc_child(struct ib_umem_odp *root_umem, unsigned long addr,
97 const struct mmu_interval_notifier_ops *ops);
98 void ib_umem_odp_release(struct ib_umem_odp *umem_odp);
100 int ib_umem_odp_map_dma_pages(struct ib_umem_odp *umem_odp, u64 start_offset,
101 u64 bcnt, u64 access_mask,
102 unsigned long current_seq);
104 void ib_umem_odp_unmap_dma_pages(struct ib_umem_odp *umem_odp, u64 start_offset,
107 #else /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */
109 static inline struct ib_umem_odp *
110 ib_umem_odp_get(struct ib_device *device, unsigned long addr, size_t size,
111 int access, const struct mmu_interval_notifier_ops *ops)
113 return ERR_PTR(-EINVAL);
116 static inline void ib_umem_odp_release(struct ib_umem_odp *umem_odp) {}
118 #endif /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */
120 #endif /* IB_UMEM_ODP_H */