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
);
91 bool dax_lock_mapping_entry(struct page
*page
);
92 void dax_unlock_mapping_entry(struct page
*page
);
94 static inline bool bdev_dax_supported(struct block_device
*bdev
,
100 static inline struct dax_device
*fs_dax_get_by_host(const char *host
)
105 static inline void fs_put_dax(struct dax_device
*dax_dev
)
109 static inline struct dax_device
*fs_dax_get_by_bdev(struct block_device
*bdev
)
114 static inline struct page
*dax_layout_busy_page(struct address_space
*mapping
)
119 static inline int dax_writeback_mapping_range(struct address_space
*mapping
,
120 struct block_device
*bdev
, struct writeback_control
*wbc
)
125 static inline bool dax_lock_mapping_entry(struct page
*page
)
127 if (IS_DAX(page
->mapping
->host
))
132 static inline void dax_unlock_mapping_entry(struct page
*page
)
137 int dax_read_lock(void);
138 void dax_read_unlock(int id
);
139 bool dax_alive(struct dax_device
*dax_dev
);
140 void *dax_get_private(struct dax_device
*dax_dev
);
141 long dax_direct_access(struct dax_device
*dax_dev
, pgoff_t pgoff
, long nr_pages
,
142 void **kaddr
, pfn_t
*pfn
);
143 size_t dax_copy_from_iter(struct dax_device
*dax_dev
, pgoff_t pgoff
, void *addr
,
144 size_t bytes
, struct iov_iter
*i
);
145 size_t dax_copy_to_iter(struct dax_device
*dax_dev
, pgoff_t pgoff
, void *addr
,
146 size_t bytes
, struct iov_iter
*i
);
147 void dax_flush(struct dax_device
*dax_dev
, void *addr
, size_t size
);
149 ssize_t
dax_iomap_rw(struct kiocb
*iocb
, struct iov_iter
*iter
,
150 const struct iomap_ops
*ops
);
151 vm_fault_t
dax_iomap_fault(struct vm_fault
*vmf
, enum page_entry_size pe_size
,
152 pfn_t
*pfnp
, int *errp
, const struct iomap_ops
*ops
);
153 vm_fault_t
dax_finish_sync_fault(struct vm_fault
*vmf
,
154 enum page_entry_size pe_size
, pfn_t pfn
);
155 int dax_delete_mapping_entry(struct address_space
*mapping
, pgoff_t index
);
156 int dax_invalidate_mapping_entry_sync(struct address_space
*mapping
,
160 int __dax_zero_page_range(struct block_device
*bdev
,
161 struct dax_device
*dax_dev
, sector_t sector
,
162 unsigned int offset
, unsigned int length
);
164 static inline int __dax_zero_page_range(struct block_device
*bdev
,
165 struct dax_device
*dax_dev
, sector_t sector
,
166 unsigned int offset
, unsigned int length
)
172 static inline bool dax_mapping(struct address_space
*mapping
)
174 return mapping
->host
&& IS_DAX(mapping
->host
);