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 12 struct ib_umem_odp { 13 struct ib_umem umem; 14 struct mmu_interval_notifier notifier; 15 struct pid *tgid; 16 17 /* 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 20 * contain NULL. 21 */ 22 struct page **page_list; 23 /* 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. 28 */ 29 dma_addr_t *dma_list; 30 /* 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. 34 */ 35 struct mutex umem_mutex; 36 void *private; /* for the HW driver to use. */ 37 38 int npages; 39 40 /* 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 44 * directly. 45 */ 46 bool is_implicit_odp; 47 48 unsigned int page_shift; 49 }; 50 51 static inline struct ib_umem_odp *to_ib_umem_odp(struct ib_umem *umem) 52 { 53 return container_of(umem, struct ib_umem_odp, umem); 54 } 55 56 /* Returns the first page of an ODP umem. */ 57 static inline unsigned long ib_umem_start(struct ib_umem_odp *umem_odp) 58 { 59 return umem_odp->notifier.interval_tree.start; 60 } 61 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) 64 { 65 return umem_odp->notifier.interval_tree.last + 1; 66 } 67 68 static inline size_t ib_umem_odp_num_pages(struct ib_umem_odp *umem_odp) 69 { 70 return (ib_umem_end(umem_odp) - ib_umem_start(umem_odp)) >> 71 umem_odp->page_shift; 72 } 73 74 /* 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. 78 * 79 * Be aware that upgrading a mapped address might result in change of 80 * the DMA address for the page. 81 */ 82 #define ODP_READ_ALLOWED_BIT (1<<0ULL) 83 #define ODP_WRITE_ALLOWED_BIT (1<<1ULL) 84 85 #define ODP_DMA_ADDR_MASK (~(ODP_READ_ALLOWED_BIT | ODP_WRITE_ALLOWED_BIT)) 86 87 #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING 88 89 struct ib_umem_odp * 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, 93 int access); 94 struct ib_umem_odp * 95 ib_umem_odp_alloc_child(struct ib_umem_odp *root_umem, unsigned long addr, 96 size_t size, 97 const struct mmu_interval_notifier_ops *ops); 98 void ib_umem_odp_release(struct ib_umem_odp *umem_odp); 99 100 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); 103 104 void ib_umem_odp_unmap_dma_pages(struct ib_umem_odp *umem_odp, u64 start_offset, 105 u64 bound); 106 107 #else /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */ 108 109 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) 112 { 113 return ERR_PTR(-EINVAL); 114 } 115 116 static inline void ib_umem_odp_release(struct ib_umem_odp *umem_odp) {} 117 118 #endif /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */ 119 120 #endif /* IB_UMEM_ODP_H */ 121