1 /* SPDX-License-Identifier: GPL-2.0 */
7 #include <linux/radix-tree.h>
8 #include <asm/pgtable.h>
12 struct dax_operations {
14 * direct_access: translate a device-relative
15 * logical-page-offset into an absolute physical pfn. Return the
16 * number of pages available for DAX at that pfn.
18 long (*direct_access)(struct dax_device *, pgoff_t, long,
20 /* copy_from_iter: required operation for fs-dax direct-i/o */
21 size_t (*copy_from_iter)(struct dax_device *, pgoff_t, void *, size_t,
23 /* copy_to_iter: required operation for fs-dax direct-i/o */
24 size_t (*copy_to_iter)(struct dax_device *, pgoff_t, void *, size_t,
28 extern struct attribute_group dax_attribute_group;
30 #if IS_ENABLED(CONFIG_DAX)
31 struct dax_device *dax_get_by_host(const char *host);
32 struct dax_device *alloc_dax(void *private, const char *host,
33 const struct dax_operations *ops);
34 void put_dax(struct dax_device *dax_dev);
35 void kill_dax(struct dax_device *dax_dev);
36 void dax_write_cache(struct dax_device *dax_dev, bool wc);
37 bool dax_write_cache_enabled(struct dax_device *dax_dev);
39 static inline struct dax_device *dax_get_by_host(const char *host)
43 static inline struct dax_device *alloc_dax(void *private, const char *host,
44 const struct dax_operations *ops)
47 * Callers should check IS_ENABLED(CONFIG_DAX) to know if this
48 * NULL is an error or expected.
52 static inline void put_dax(struct dax_device *dax_dev)
55 static inline void kill_dax(struct dax_device *dax_dev)
58 static inline void dax_write_cache(struct dax_device *dax_dev, bool wc)
61 static inline bool dax_write_cache_enabled(struct dax_device *dax_dev)
67 struct writeback_control;
68 int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff);
69 #if IS_ENABLED(CONFIG_FS_DAX)
70 bool __bdev_dax_supported(struct block_device *bdev, int blocksize);
71 static inline bool bdev_dax_supported(struct block_device *bdev, int blocksize)
73 return __bdev_dax_supported(bdev, blocksize);
76 static inline struct dax_device *fs_dax_get_by_host(const char *host)
78 return dax_get_by_host(host);
81 static inline void fs_put_dax(struct dax_device *dax_dev)
86 struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev);
87 int dax_writeback_mapping_range(struct address_space *mapping,
88 struct block_device *bdev, struct writeback_control *wbc);
90 struct page *dax_layout_busy_page(struct address_space *mapping);
92 static inline bool bdev_dax_supported(struct block_device *bdev,
98 static inline struct dax_device *fs_dax_get_by_host(const char *host)
103 static inline void fs_put_dax(struct dax_device *dax_dev)
107 static inline struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev)
112 static inline struct page *dax_layout_busy_page(struct address_space *mapping)
117 static inline int dax_writeback_mapping_range(struct address_space *mapping,
118 struct block_device *bdev, struct writeback_control *wbc)
124 int dax_read_lock(void);
125 void dax_read_unlock(int id);
126 bool dax_alive(struct dax_device *dax_dev);
127 void *dax_get_private(struct dax_device *dax_dev);
128 long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
129 void **kaddr, pfn_t *pfn);
130 size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
131 size_t bytes, struct iov_iter *i);
132 size_t dax_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
133 size_t bytes, struct iov_iter *i);
134 void dax_flush(struct dax_device *dax_dev, void *addr, size_t size);
136 ssize_t dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
137 const struct iomap_ops *ops);
138 vm_fault_t dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
139 pfn_t *pfnp, int *errp, const struct iomap_ops *ops);
140 vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
141 enum page_entry_size pe_size, pfn_t pfn);
142 int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
143 int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
147 int __dax_zero_page_range(struct block_device *bdev,
148 struct dax_device *dax_dev, sector_t sector,
149 unsigned int offset, unsigned int length);
151 static inline int __dax_zero_page_range(struct block_device *bdev,
152 struct dax_device *dax_dev, sector_t sector,
153 unsigned int offset, unsigned int length)
159 static inline bool dax_mapping(struct address_space *mapping)
161 return mapping->host && IS_DAX(mapping->host);