drivers/dax/dax-private.h

   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 */
  13 struct dax_device;
  14 struct dax_device *inode_dax(struct inode *inode);
  15 struct inode *dax_inode(struct dax_device *dax_dev);
  16 int dax_bus_init(void);
  17 void 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  */
  31 struct 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  */
  49 struct 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  */
  61 struct 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  */
  81 struct 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  */
 101 void run_dax(struct dax_device *dax_dev);
 102
 103 static inline struct dev_dax *to_dev_dax(struct device *dev)
 104 {
 105         return container_of(dev, struct dev_dax, dev);
 106 }
 107
 108 static inline struct dax_mapping *to_dax_mapping(struct device *dev)
 109 {
 110         return container_of(dev, struct dax_mapping, dev);
 111 }
 112
 113 phys_addr_t dax_pgoff_to_phys(struct dev_dax *dev_dax, pgoff_t pgoff, unsigned long size);
 114
 115 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 116 static 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
 127 static inline bool dax_align_valid(unsigned long align)
 128 {
 129         return align == PAGE_SIZE;
 130 }
 131 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
 132 #endif