--- /dev/null
+/*
+ * 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 */
Code Review / kvmfornfv.git / blobdiff