diff options
Diffstat (limited to 'kernel/include/rdma/ib_umem_odp.h')
| -rw-r--r-- | kernel/include/rdma/ib_umem_odp.h | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/kernel/include/rdma/ib_umem_odp.h b/kernel/include/rdma/ib_umem_odp.h new file mode 100644 index 000000000..3da0b1670 --- /dev/null +++ b/kernel/include/rdma/ib_umem_odp.h @@ -0,0 +1,160 @@ +/* + * 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 */ |