1 files changed, 115 insertions, 0 deletions
diff --git a/include/rdma/ib_umem_odp.h b/include/rdma/ib_umem_odp.h
new file mode 100644
index 000000000..0844c1d05
--- /dev/null
+++ b/include/rdma/ib_umem_odp.h
@@ -0,0 +1,115 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
+/*
+ * Copyright (c) 2014 Mellanox Technologies. All rights reserved.
+ */
+
+#ifndef IB_UMEM_ODP_H
+#define IB_UMEM_ODP_H
+
+#include <rdma/ib_umem.h>
+#include <rdma/ib_verbs.h>
+
+struct ib_umem_odp {
+	struct ib_umem umem;
+	struct mmu_interval_notifier notifier;
+	struct pid *tgid;
+
+	/* An array of the pfns included in the on-demand paging umem. */
+	unsigned long *pfn_list;
+
+	/*
+	 * An array with DMA addresses mapped for pfns in pfn_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 npages;
+
+	/*
+	 * An implicit odp umem cannot be DMA mapped, has 0 length, and serves
+	 * only as an anchor for the driver to hold onto the per_mm. FIXME:
+	 * This should be removed and drivers should work with the per_mm
+	 * directly.
+	 */
+	bool is_implicit_odp;
+
+	unsigned int		page_shift;
+};
+
+static inline struct ib_umem_odp *to_ib_umem_odp(struct ib_umem *umem)
+{
+	return container_of(umem, struct ib_umem_odp, umem);
+}
+
+/* Returns the first page of an ODP umem. */
+static inline unsigned long ib_umem_start(struct ib_umem_odp *umem_odp)
+{
+	return umem_odp->notifier.interval_tree.start;
+}
+
+/* Returns the address of the page after the last one of an ODP umem. */
+static inline unsigned long ib_umem_end(struct ib_umem_odp *umem_odp)
+{
+	return umem_odp->notifier.interval_tree.last + 1;
+}
+
+static inline size_t ib_umem_odp_num_pages(struct ib_umem_odp *umem_odp)
+{
+	return (ib_umem_end(umem_odp) - ib_umem_start(umem_odp)) >>
+	       umem_odp->page_shift;
+}
+
+/*
+ * 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))
+
+#ifdef CONFIG_INFINIBAND_ON_DEMAND_PAGING
+
+struct ib_umem_odp *
+ib_umem_odp_get(struct ib_device *device, unsigned long addr, size_t size,
+		int access, const struct mmu_interval_notifier_ops *ops);
+struct ib_umem_odp *ib_umem_odp_alloc_implicit(struct ib_device *device,
+					       int access);
+struct ib_umem_odp *
+ib_umem_odp_alloc_child(struct ib_umem_odp *root_umem, unsigned long addr,
+			size_t size,
+			const struct mmu_interval_notifier_ops *ops);
+void ib_umem_odp_release(struct ib_umem_odp *umem_odp);
+
+int ib_umem_odp_map_dma_and_lock(struct ib_umem_odp *umem_odp, u64 start_offset,
+				 u64 bcnt, u64 access_mask, bool fault);
+
+void ib_umem_odp_unmap_dma_pages(struct ib_umem_odp *umem_odp, u64 start_offset,
+				 u64 bound);
+
+#else /* CONFIG_INFINIBAND_ON_DEMAND_PAGING */
+
+static inline struct ib_umem_odp *
+ib_umem_odp_get(struct ib_device *device, unsigned long addr, size_t size,
+		int access, const struct mmu_interval_notifier_ops *ops)
+{
+	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 */