/*- * SPDX-License-Identifier: BSD-2-Clause OR GPL-2.0 * * Copyright (c) 2014 Mellanox Technologies. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU * General Public License (GPL) Version 2, available from the file * COPYING in the main directory of this source tree, or the * OpenIB.org BSD license below: * * Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * - Redistributions of source code must retain the above * copyright notice, this list of conditions and the following * disclaimer. * * - Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials * provided with the distribution. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ #ifndef IB_UMEM_ODP_H #define IB_UMEM_ODP_H #include <linux/rbtree.h> #include <rdma/ib_umem.h> #include <rdma/ib_verbs.h> struct umem_odp_node { u64 __subtree_last; struct rb_node rb; }; struct ib_umem_odp { struct ib_umem umem; struct ib_ucontext_per_mm *per_mm; /* * An array of the pages included in the on-demand paging umem. * Indices of pages that are currently not mapped into the device will * contain NULL. */ struct page **page_list; /* * An array of the same size as page_list, with DMA addresses mapped * for pages the pages in page_list. The lower two bits designate * access permissions. See ODP_READ_ALLOWED_BIT and * ODP_WRITE_ALLOWED_BIT. */ dma_addr_t *dma_list; /* * The umem_mutex protects the page_list and dma_list fields of an ODP * umem, allowing only a single thread to map/unmap pages. The mutex * also protects access to the mmu notifier counters. */ struct mutex umem_mutex; void *private; /* for the HW driver to use. */ int notifiers_seq; int notifiers_count; /* Tree tracking */ struct umem_odp_node interval_tree; struct completion notifier_completion; int dying; struct work_struct work; }; static inline struct ib_umem_odp *to_ib_umem_odp(struct ib_umem *umem) { return container_of(umem, struct ib_umem_odp, umem); } #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING struct ib_ucontext_per_mm { struct ib_ucontext *context; struct mm_struct *mm; struct pid *tgid; bool active; struct rb_root_cached umem_tree; /* Protects umem_tree */ struct rw_semaphore umem_rwsem; struct mmu_notifier mn; unsigned int odp_mrs_count; struct list_head ucontext_list; struct rcu_head rcu; }; int ib_umem_odp_get(struct ib_umem_odp *umem_odp, int access); struct ib_umem_odp *ib_alloc_odp_umem(struct ib_ucontext_per_mm *per_mm, unsigned long addr, size_t size); void ib_umem_odp_release(struct ib_umem_odp *umem_odp); /* * The lower 2 bits of the DMA address signal the R/W permissions for * the entry. To upgrade the permissions, provide the appropriate * bitmask to the map_dma_pages function. * * Be aware that upgrading a mapped address might result in change of * the DMA address for the page. */ #define ODP_READ_ALLOWED_BIT (1<<0ULL) #define ODP_WRITE_ALLOWED_BIT (1<<1ULL) #define ODP_DMA_ADDR_MASK (~(ODP_READ_ALLOWED_BIT | ODP_WRITE_ALLOWED_BIT)) int ib_umem_odp_map_dma_pages(struct ib_umem_odp *umem_odp, u64 start_offset, u64 bcnt, u64 access_mask, unsigned long current_seq); void ib_umem_odp_unmap_dma_pages(struct ib_umem_odp *umem_odp, u64 start_offset, u64 bound); typedef int (*umem_call_back)(struct ib_umem_odp *item, u64 start, u64 end, void *cookie); /* * Call the callback on each ib_umem in the range. Returns the logical or of * the return values of the functions called. */ int rbt_ib_umem_for_each_in_range(struct rb_root_cached *root, u64 start, u64 end, umem_call_back cb, bool blockable, void *cookie); /* * Find first region intersecting with address range. * Return NULL if not found */ struct ib_umem_odp *rbt_ib_umem_lookup(struct rb_root_cached *root, u64 addr, u64 length); static inline int ib_umem_mmu_notifier_retry(struct ib_umem_odp *umem_odp, unsigned long mmu_seq) { /* * This code is strongly based on the KVM code from * mmu_notifier_retry. Should be called with * the relevant locks taken (umem_odp->umem_mutex * and the ucontext umem_mutex semaphore locked for read). */ if (unlikely(umem_odp->notifiers_count)) return 1; if (umem_odp->notifiers_seq != mmu_seq) return 1; return 0; } #else /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */ static inline int ib_umem_odp_get(struct ib_umem_odp *umem_odp, int access) { return -EINVAL; } static inline struct ib_umem_odp * ib_alloc_odp_umem(struct ib_ucontext *context, unsigned long addr, size_t size) { return ERR_PTR(-EINVAL); } static inline void ib_umem_odp_release(struct ib_umem_odp *umem_odp) {} #endif /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */ #endif /* IB_UMEM_ODP_H */
