1 /* SPDX-License-Identifier: GPL-2.0 */
7 #include <linux/radix-tree.h>
9 typedef unsigned long dax_entry_t;
17 enum dax_access_mode {
22 struct dax_operations {
24 * direct_access: translate a device-relative
25 * logical-page-offset into an absolute physical pfn. Return the
26 * number of pages available for DAX at that pfn.
28 long (*direct_access)(struct dax_device *, pgoff_t, long,
29 enum dax_access_mode, void **, pfn_t *);
31 * Validate whether this device is usable as an fsdax backing
34 bool (*dax_supported)(struct dax_device *, struct block_device *, int,
36 /* zero_page_range: required operation. Zero page range */
37 int (*zero_page_range)(struct dax_device *, pgoff_t, size_t);
39 * recovery_write: recover a poisoned range by DAX device driver
40 * capable of clearing poison.
42 size_t (*recovery_write)(struct dax_device *dax_dev, pgoff_t pgoff,
43 void *addr, size_t bytes, struct iov_iter *iter);
46 #if IS_ENABLED(CONFIG_DAX)
47 struct dax_device *alloc_dax(void *private, const struct dax_operations *ops);
48 void put_dax(struct dax_device *dax_dev);
49 void kill_dax(struct dax_device *dax_dev);
50 void dax_write_cache(struct dax_device *dax_dev, bool wc);
51 bool dax_write_cache_enabled(struct dax_device *dax_dev);
52 bool dax_synchronous(struct dax_device *dax_dev);
53 void set_dax_synchronous(struct dax_device *dax_dev);
54 size_t dax_recovery_write(struct dax_device *dax_dev, pgoff_t pgoff,
55 void *addr, size_t bytes, struct iov_iter *i);
57 * Check if given mapping is supported by the file / underlying device.
59 static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
60 struct dax_device *dax_dev)
62 if (!(vma->vm_flags & VM_SYNC))
64 if (!IS_DAX(file_inode(vma->vm_file)))
66 return dax_synchronous(dax_dev);
69 static inline struct dax_device *alloc_dax(void *private,
70 const struct dax_operations *ops)
73 * Callers should check IS_ENABLED(CONFIG_DAX) to know if this
74 * NULL is an error or expected.
78 static inline void put_dax(struct dax_device *dax_dev)
81 static inline void kill_dax(struct dax_device *dax_dev)
84 static inline void dax_write_cache(struct dax_device *dax_dev, bool wc)
87 static inline bool dax_write_cache_enabled(struct dax_device *dax_dev)
91 static inline bool dax_synchronous(struct dax_device *dax_dev)
95 static inline void set_dax_synchronous(struct dax_device *dax_dev)
98 static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
99 struct dax_device *dax_dev)
101 return !(vma->vm_flags & VM_SYNC);
103 static inline size_t dax_recovery_write(struct dax_device *dax_dev,
104 pgoff_t pgoff, void *addr, size_t bytes, struct iov_iter *i)
110 void set_dax_nocache(struct dax_device *dax_dev);
111 void set_dax_nomc(struct dax_device *dax_dev);
113 struct writeback_control;
114 #if defined(CONFIG_BLOCK) && defined(CONFIG_FS_DAX)
115 int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk);
116 void dax_remove_host(struct gendisk *disk);
117 struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev,
119 static inline void fs_put_dax(struct dax_device *dax_dev)
124 static inline int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk)
128 static inline void dax_remove_host(struct gendisk *disk)
131 static inline struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev,
136 static inline void fs_put_dax(struct dax_device *dax_dev)
139 #endif /* CONFIG_BLOCK && CONFIG_FS_DAX */
141 #if IS_ENABLED(CONFIG_FS_DAX)
142 int dax_writeback_mapping_range(struct address_space *mapping,
143 struct dax_device *dax_dev, struct writeback_control *wbc);
145 struct page *dax_layout_busy_page(struct address_space *mapping);
146 struct page *dax_layout_busy_page_range(struct address_space *mapping, loff_t start, loff_t end);
147 dax_entry_t dax_lock_page(struct page *page);
148 void dax_unlock_page(struct page *page, dax_entry_t cookie);
150 static inline struct page *dax_layout_busy_page(struct address_space *mapping)
155 static inline struct page *dax_layout_busy_page_range(struct address_space *mapping, pgoff_t start, pgoff_t nr_pages)
160 static inline int dax_writeback_mapping_range(struct address_space *mapping,
161 struct dax_device *dax_dev, struct writeback_control *wbc)
166 static inline dax_entry_t dax_lock_page(struct page *page)
168 if (IS_DAX(page->mapping->host))
173 static inline void dax_unlock_page(struct page *page, dax_entry_t cookie)
178 int dax_zero_range(struct inode *inode, loff_t pos, loff_t len, bool *did_zero,
179 const struct iomap_ops *ops);
180 int dax_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,
181 const struct iomap_ops *ops);
183 #if IS_ENABLED(CONFIG_DAX)
184 int dax_read_lock(void);
185 void dax_read_unlock(int id);
187 static inline int dax_read_lock(void)
192 static inline void dax_read_unlock(int id)
195 #endif /* CONFIG_DAX */
196 bool dax_alive(struct dax_device *dax_dev);
197 void *dax_get_private(struct dax_device *dax_dev);
198 long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
199 enum dax_access_mode mode, void **kaddr, pfn_t *pfn);
200 size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
201 size_t bytes, struct iov_iter *i);
202 size_t dax_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
203 size_t bytes, struct iov_iter *i);
204 int dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
206 void dax_flush(struct dax_device *dax_dev, void *addr, size_t size);
208 ssize_t dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
209 const struct iomap_ops *ops);
210 vm_fault_t dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
211 pfn_t *pfnp, int *errp, const struct iomap_ops *ops);
212 vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
213 enum page_entry_size pe_size, pfn_t pfn);
214 int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
215 int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
217 static inline bool dax_mapping(struct address_space *mapping)
219 return mapping->host && IS_DAX(mapping->host);
222 #ifdef CONFIG_DEV_DAX_HMEM_DEVICES
223 void hmem_register_device(int target_nid, struct resource *r);
225 static inline void hmem_register_device(int target_nid, struct resource *r)