1/* SPDX-License-Identifier: GPL-2.0-only */
  2/*
  3 * Copyright(c) 2016 Intel Corporation. All rights reserved.
  4 */
  5#ifndef __DAX_PRIVATE_H__
  6#define __DAX_PRIVATE_H__
  7
  8#include <linux/device.h>
  9#include <linux/cdev.h>
 10#include <linux/idr.h>
 11
 12/* private routines between core files */
 13struct dax_device;
 14struct dax_device *inode_dax(struct inode *inode);
 15struct inode *dax_inode(struct dax_device *dax_dev);
 16int dax_bus_init(void);
 17void dax_bus_exit(void);
 18
 19/**
 20 * struct dax_region - mapping infrastructure for dax devices
 21 * @id: kernel-wide unique region for a memory range
 22 * @target_node: effective numa node if this memory range is onlined
 23 * @kref: to pin while other agents have a need to do lookups
 24 * @dev: parent device backing this region
 25 * @align: allocation and mapping alignment for child dax devices
 26 * @ida: instance id allocator
 27 * @res: resource tree to track instance allocations
 28 * @seed: allow userspace to find the first unbound seed device
 29 * @youngest: allow userspace to find the most recently created device
 30 */
 31struct dax_region {
 32	int id;
 33	int target_node;
 34	struct kref kref;
 35	struct device *dev;
 36	unsigned int align;
 37	struct ida ida;
 38	struct resource res;
 39	struct device *seed;
 40	struct device *youngest;
 41};
 42
 43/**
 44 * struct dax_mapping - device to display mapping range attributes
 45 * @dev: device representing this range
 46 * @range_id: index within dev_dax ranges array
 47 * @id: ida of this mapping
 48 */
 49struct dax_mapping {
 50	struct device dev;
 51	int range_id;
 52	int id;
 53};
 54
 55/**
 56 * struct dev_dax_range - tuple represenging a range of memory used by dev_dax
 57 * @pgoff: page offset
 58 * @range: resource-span
 59 * @mapping: reference to the dax_mapping for this range
 60 */
 61struct dev_dax_range {
 62	unsigned long pgoff;
 63	struct range range;
 64	struct dax_mapping *mapping;
 65};
 66
 67/**
 68 * struct dev_dax - instance data for a subdivision of a dax region, and
 69 * data while the device is activated in the driver.
 70 * @region - parent region
 71 * @dax_dev - core dax functionality
 72 * @target_node: effective numa node if dev_dax memory range is onlined
 73 * @dyn_id: is this a dynamic or statically created instance
 74 * @id: ida allocated id when the dax_region is not static
 75 * @ida: mapping id allocator
 76 * @dev - device core
 77 * @pgmap - pgmap for memmap setup / lifetime (driver owned)
 78 * @nr_range: size of @ranges
 79 * @ranges: range tuples of memory used
 80 */
 81struct dev_dax {
 82	struct dax_region *region;
 83	struct dax_device *dax_dev;
 84	unsigned int align;
 85	int target_node;
 86	bool dyn_id;
 87	int id;
 88	struct ida ida;
 89	struct device dev;
 90	struct dev_pagemap *pgmap;
 91	bool memmap_on_memory;
 92	int nr_range;
 93	struct dev_dax_range *ranges;
 94};
 95
 96/*
 97 * While run_dax() is potentially a generic operation that could be
 98 * defined in include/linux/dax.h we don't want to grow any users
 99 * outside of drivers/dax/
100 */
101void run_dax(struct dax_device *dax_dev);
102
103static inline struct dev_dax *to_dev_dax(struct device *dev)
104{
105	return container_of(dev, struct dev_dax, dev);
106}
107
108static inline struct dax_mapping *to_dax_mapping(struct device *dev)
109{
110	return container_of(dev, struct dax_mapping, dev);
111}
112
113phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff, unsigned long size);
114
115#ifdef CONFIG_TRANSPARENT_HUGEPAGE
116static inline bool dax_align_valid(unsigned long align)
117{
118	if (align == PUD_SIZE && IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD))
119		return true;
120	if (align == PMD_SIZE && has_transparent_hugepage())
121		return true;
122	if (align == PAGE_SIZE)
123		return true;
124	return false;
125}
126#else
127static inline bool dax_align_valid(unsigned long align)
128{
129	return align == PAGE_SIZE;
130}
131#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
132#endif