/* * 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 <rdma/ib_umem.h> #include <rdma/ib_verbs.h> #include <linux/interval_tree.h> struct umem_odp_node { u64 __subtree_last; struct rb_node rb; }; struct ib_umem_odp { /* * 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. */ /* When false, use the notifier counter in the ucontext struct. */ bool mn_counters_active; int notifiers_seq; int notifiers_count; /* A linked list of umems that don't have private mmu notifier * counters yet. */ struct list_head no_private_counters; struct ib_umem *umem; /* Tree tracking */ struct umem_odp_node interval_tree; struct completion notifier_completion; int dying; }; #ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING int ib_umem_odp_get(struct ib_ucontext *context, struct ib_umem *umem); void ib_umem_odp_release(struct ib_umem *umem); /* * 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 *umem, u64 start_offset, u64 bcnt, u64 access_mask, unsigned long current_seq); void ib_umem_odp_unmap_dma_pages(struct ib_umem *umem, u64 start_offset, u64 bound); void rbt_ib_umem_insert(struct umem_odp_node *node, struct rb_root *root); void rbt_ib_umem_remove(struct umem_odp_node *node, struct rb_root *root); typedef int (*umem_call_back)(struct ib_umem *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 *root, u64 start, u64 end, umem_call_back cb, void *cookie); struct umem_odp_node *rbt_ib_umem_iter_first(struct rb_root *root, u64 start, u64 last); struct umem_odp_node *rbt_ib_umem_iter_next(struct umem_odp_node *node, u64 start, u64 last); static inline int ib_umem_mmu_notifier_retry(struct ib_umem *item, 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 (item->odp_data->umem_mutex * and the ucontext umem_mutex semaphore locked for read). */ /* Do not allow page faults while the new ib_umem hasn't seen a state * with zero notifiers yet, and doesn't have its own valid set of * private counters. */ if (!item->odp_data->mn_counters_active) return 1; if (unlikely(item->odp_data->notifiers_count)) return 1; if (item->odp_data->notifiers_seq != mmu_seq) return 1; return 0; } #else /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */ static inline int ib_umem_odp_get(struct ib_ucontext *context, struct ib_umem *umem) { return -EINVAL; } static inline void ib_umem_odp_release(struct ib_umem *umem) {} #endif /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */ #endif /* IB_UMEM_ODP_H */