1 /* SPDX-License-Identifier: GPL-2.0 */
7 #include <linux/radix-tree.h>
8 #include <asm/pgtable.h>
10 typedef unsigned long dax_entry_t
;
14 struct dax_operations
{
16 * direct_access: translate a device-relative
17 * logical-page-offset into an absolute physical pfn. Return the
18 * number of pages available for DAX at that pfn.
20 long (*direct_access
)(struct dax_device
*, pgoff_t
, long,
22 /* copy_from_iter: required operation for fs-dax direct-i/o */
23 size_t (*copy_from_iter
)(struct dax_device
*, pgoff_t
, void *, size_t,
25 /* copy_to_iter: required operation for fs-dax direct-i/o */
26 size_t (*copy_to_iter
)(struct dax_device
*, pgoff_t
, void *, size_t,
30 extern struct attribute_group dax_attribute_group
;
32 #if IS_ENABLED(CONFIG_DAX)
33 struct dax_device
*dax_get_by_host(const char *host
);
34 struct dax_device
*alloc_dax(void *private, const char *host
,
35 const struct dax_operations
*ops
);
36 void put_dax(struct dax_device
*dax_dev
);
37 void kill_dax(struct dax_device
*dax_dev
);
38 void dax_write_cache(struct dax_device
*dax_dev
, bool wc
);
39 bool dax_write_cache_enabled(struct dax_device
*dax_dev
);
41 static inline struct dax_device
*dax_get_by_host(const char *host
)
45 static inline struct dax_device
*alloc_dax(void *private, const char *host
,
46 const struct dax_operations
*ops
)
49 * Callers should check IS_ENABLED(CONFIG_DAX) to know if this
50 * NULL is an error or expected.
54 static inline void put_dax(struct dax_device
*dax_dev
)
57 static inline void kill_dax(struct dax_device
*dax_dev
)
60 static inline void dax_write_cache(struct dax_device
*dax_dev
, bool wc
)
63 static inline bool dax_write_cache_enabled(struct dax_device
*dax_dev
)
69 struct writeback_control
;
70 int bdev_dax_pgoff(struct block_device
*, sector_t
, size_t, pgoff_t
*pgoff
);
71 #if IS_ENABLED(CONFIG_FS_DAX)
72 bool __bdev_dax_supported(struct block_device
*bdev
, int blocksize
);
73 static inline bool bdev_dax_supported(struct block_device
*bdev
, int blocksize
)
75 return __bdev_dax_supported(bdev
, blocksize
);
78 static inline struct dax_device
*fs_dax_get_by_host(const char *host
)
80 return dax_get_by_host(host
);
83 static inline void fs_put_dax(struct dax_device
*dax_dev
)
88 struct dax_device
*fs_dax_get_by_bdev(struct block_device
*bdev
);
89 int dax_writeback_mapping_range(struct address_space
*mapping
,
90 struct block_device
*bdev
, struct writeback_control
*wbc
);
92 struct page
*dax_layout_busy_page(struct address_space
*mapping
);
93 dax_entry_t
dax_lock_page(struct page
*page
);
94 void dax_unlock_page(struct page
*page
, dax_entry_t cookie
);
96 static inline bool bdev_dax_supported(struct block_device
*bdev
,
102 static inline struct dax_device
*fs_dax_get_by_host(const char *host
)
107 static inline void fs_put_dax(struct dax_device
*dax_dev
)
111 static inline struct dax_device
*fs_dax_get_by_bdev(struct block_device
*bdev
)
116 static inline struct page
*dax_layout_busy_page(struct address_space
*mapping
)
121 static inline int dax_writeback_mapping_range(struct address_space
*mapping
,
122 struct block_device
*bdev
, struct writeback_control
*wbc
)
127 static inline dax_entry_t
dax_lock_page(struct page
*page
)
129 if (IS_DAX(page
->mapping
->host
))
134 static inline void dax_unlock_page(struct page
*page
, dax_entry_t cookie
)
139 int dax_read_lock(void);
140 void dax_read_unlock(int id
);
141 bool dax_alive(struct dax_device
*dax_dev
);
142 void *dax_get_private(struct dax_device
*dax_dev
);
143 long dax_direct_access(struct dax_device
*dax_dev
, pgoff_t pgoff
, long nr_pages
,
144 void **kaddr
, pfn_t
*pfn
);
145 size_t dax_copy_from_iter(struct dax_device
*dax_dev
, pgoff_t pgoff
, void *addr
,
146 size_t bytes
, struct iov_iter
*i
);
147 size_t dax_copy_to_iter(struct dax_device
*dax_dev
, pgoff_t pgoff
, void *addr
,
148 size_t bytes
, struct iov_iter
*i
);
149 void dax_flush(struct dax_device
*dax_dev
, void *addr
, size_t size
);
151 ssize_t
dax_iomap_rw(struct kiocb
*iocb
, struct iov_iter
*iter
,
152 const struct iomap_ops
*ops
);
153 vm_fault_t
dax_iomap_fault(struct vm_fault
*vmf
, enum page_entry_size pe_size
,
154 pfn_t
*pfnp
, int *errp
, const struct iomap_ops
*ops
);
155 vm_fault_t
dax_finish_sync_fault(struct vm_fault
*vmf
,
156 enum page_entry_size pe_size
, pfn_t pfn
);
157 int dax_delete_mapping_entry(struct address_space
*mapping
, pgoff_t index
);
158 int dax_invalidate_mapping_entry_sync(struct address_space
*mapping
,
162 int __dax_zero_page_range(struct block_device
*bdev
,
163 struct dax_device
*dax_dev
, sector_t sector
,
164 unsigned int offset
, unsigned int length
);
166 static inline int __dax_zero_page_range(struct block_device
*bdev
,
167 struct dax_device
*dax_dev
, sector_t sector
,
168 unsigned int offset
, unsigned int length
)
174 static inline bool dax_mapping(struct address_space
*mapping
)
176 return mapping
->host
&& IS_DAX(mapping
->host
);