1 /* 2 * Copyright (c) 2014 Mellanox Technologies. All rights reserved. 3 * 4 * This software is available to you under a choice of one of two 5 * licenses. You may choose to be licensed under the terms of the GNU 6 * General Public License (GPL) Version 2, available from the file 7 * COPYING in the main directory of this source tree, or the 8 * OpenIB.org BSD license below: 9 * 10 * Redistribution and use in source and binary forms, with or 11 * without modification, are permitted provided that the following 12 * conditions are met: 13 * 14 * - Redistributions of source code must retain the above 15 * copyright notice, this list of conditions and the following 16 * disclaimer. 17 * 18 * - Redistributions in binary form must reproduce the above 19 * copyright notice, this list of conditions and the following 20 * disclaimer in the documentation and/or other materials 21 * provided with the distribution. 22 * 23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 30 * SOFTWARE. 31 */ 32 33 #ifndef IB_UMEM_ODP_H 34 #define IB_UMEM_ODP_H 35 36 #include <rdma/ib_umem.h> 37 #include <rdma/ib_verbs.h> 38 39 struct ib_umem_odp { 40 struct ib_umem umem; 41 struct mmu_interval_notifier notifier; 42 struct pid *tgid; 43 44 /* 45 * An array of the pages included in the on-demand paging umem. 46 * Indices of pages that are currently not mapped into the device will 47 * contain NULL. 48 */ 49 struct page **page_list; 50 /* 51 * An array of the same size as page_list, with DMA addresses mapped 52 * for pages the pages in page_list. The lower two bits designate 53 * access permissions. See ODP_READ_ALLOWED_BIT and 54 * ODP_WRITE_ALLOWED_BIT. 55 */ 56 dma_addr_t *dma_list; 57 /* 58 * The umem_mutex protects the page_list and dma_list fields of an ODP 59 * umem, allowing only a single thread to map/unmap pages. The mutex 60 * also protects access to the mmu notifier counters. 61 */ 62 struct mutex umem_mutex; 63 void *private; /* for the HW driver to use. */ 64 65 int npages; 66 67 /* 68 * An implicit odp umem cannot be DMA mapped, has 0 length, and serves 69 * only as an anchor for the driver to hold onto the per_mm. FIXME: 70 * This should be removed and drivers should work with the per_mm 71 * directly. 72 */ 73 bool is_implicit_odp; 74 75 unsigned int page_shift; 76 }; 77 78 static inline struct ib_umem_odp *to_ib_umem_odp(struct ib_umem *umem) 79 { 80 return container_of(umem, struct ib_umem_odp, umem); 81 } 82 83 /* Returns the first page of an ODP umem. */ 84 static inline unsigned long ib_umem_start(struct ib_umem_odp *umem_odp) 85 { 86 return umem_odp->notifier.interval_tree.start; 87 } 88 89 /* Returns the address of the page after the last one of an ODP umem. */ 90 static inline unsigned long ib_umem_end(struct ib_umem_odp *umem_odp) 91 { 92 return umem_odp->notifier.interval_tree.last + 1; 93 } 94 95 static inline size_t ib_umem_odp_num_pages(struct ib_umem_odp *umem_odp) 96 { 97 return (ib_umem_end(umem_odp) - ib_umem_start(umem_odp)) >> 98 umem_odp->page_shift; 99 } 100 101 /* 102 * The lower 2 bits of the DMA address signal the R/W permissions for 103 * the entry. To upgrade the permissions, provide the appropriate 104 * bitmask to the map_dma_pages function. 105 * 106 * Be aware that upgrading a mapped address might result in change of 107 * the DMA address for the page. 108 */ 109 #define ODP_READ_ALLOWED_BIT (1<<0ULL) 110 #define ODP_WRITE_ALLOWED_BIT (1<<1ULL) 111 112 #define ODP_DMA_ADDR_MASK (~(ODP_READ_ALLOWED_BIT | ODP_WRITE_ALLOWED_BIT)) 113 114 #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING 115 116 struct ib_umem_odp * 117 ib_umem_odp_get(struct ib_device *device, unsigned long addr, size_t size, 118 int access, const struct mmu_interval_notifier_ops *ops); 119 struct ib_umem_odp *ib_umem_odp_alloc_implicit(struct ib_device *device, 120 int access); 121 struct ib_umem_odp * 122 ib_umem_odp_alloc_child(struct ib_umem_odp *root_umem, unsigned long addr, 123 size_t size, 124 const struct mmu_interval_notifier_ops *ops); 125 void ib_umem_odp_release(struct ib_umem_odp *umem_odp); 126 127 int ib_umem_odp_map_dma_pages(struct ib_umem_odp *umem_odp, u64 start_offset, 128 u64 bcnt, u64 access_mask, 129 unsigned long current_seq); 130 131 void ib_umem_odp_unmap_dma_pages(struct ib_umem_odp *umem_odp, u64 start_offset, 132 u64 bound); 133 134 #else /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */ 135 136 static inline struct ib_umem_odp * 137 ib_umem_odp_get(struct ib_device *device, unsigned long addr, size_t size, 138 int access, const struct mmu_interval_notifier_ops *ops) 139 { 140 return ERR_PTR(-EINVAL); 141 } 142 143 static inline void ib_umem_odp_release(struct ib_umem_odp *umem_odp) {} 144 145 #endif /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */ 146 147 #endif /* IB_UMEM_ODP_H */ 148