1 /* SPDX-License-Identifier: GPL-2.0 */
7 #include <linux/radix-tree.h>
9 /* Flag for synchronous flush */
10 #define DAXDEV_F_SYNC (1UL << 0)
12 typedef unsigned long dax_entry_t;
20 struct dax_operations {
22 * direct_access: translate a device-relative
23 * logical-page-offset into an absolute physical pfn. Return the
24 * number of pages available for DAX at that pfn.
26 long (*direct_access)(struct dax_device *, pgoff_t, long,
29 * Validate whether this device is usable as an fsdax backing
32 bool (*dax_supported)(struct dax_device *, struct block_device *, int,
34 /* copy_from_iter: required operation for fs-dax direct-i/o */
35 size_t (*copy_from_iter)(struct dax_device *, pgoff_t, void *, size_t,
37 /* copy_to_iter: required operation for fs-dax direct-i/o */
38 size_t (*copy_to_iter)(struct dax_device *, pgoff_t, void *, size_t,
40 /* zero_page_range: required operation. Zero page range */
41 int (*zero_page_range)(struct dax_device *, pgoff_t, size_t);
44 #if IS_ENABLED(CONFIG_DAX)
45 struct dax_device *alloc_dax(void *private, const struct dax_operations *ops,
47 void put_dax(struct dax_device *dax_dev);
48 void kill_dax(struct dax_device *dax_dev);
49 void dax_write_cache(struct dax_device *dax_dev, bool wc);
50 bool dax_write_cache_enabled(struct dax_device *dax_dev);
51 bool __dax_synchronous(struct dax_device *dax_dev);
52 static inline bool dax_synchronous(struct dax_device *dax_dev)
54 return __dax_synchronous(dax_dev);
56 void __set_dax_synchronous(struct dax_device *dax_dev);
57 static inline void set_dax_synchronous(struct dax_device *dax_dev)
59 __set_dax_synchronous(dax_dev);
62 * Check if given mapping is supported by the file / underlying device.
64 static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
65 struct dax_device *dax_dev)
67 if (!(vma->vm_flags & VM_SYNC))
69 if (!IS_DAX(file_inode(vma->vm_file)))
71 return dax_synchronous(dax_dev);
74 static inline struct dax_device *alloc_dax(void *private,
75 const struct dax_operations *ops, unsigned long flags)
78 * Callers should check IS_ENABLED(CONFIG_DAX) to know if this
79 * NULL is an error or expected.
83 static inline void put_dax(struct dax_device *dax_dev)
86 static inline void kill_dax(struct dax_device *dax_dev)
89 static inline void dax_write_cache(struct dax_device *dax_dev, bool wc)
92 static inline bool dax_write_cache_enabled(struct dax_device *dax_dev)
96 static inline bool dax_synchronous(struct dax_device *dax_dev)
100 static inline void set_dax_synchronous(struct dax_device *dax_dev)
103 static inline bool daxdev_mapping_supported(struct vm_area_struct *vma,
104 struct dax_device *dax_dev)
106 return !(vma->vm_flags & VM_SYNC);
110 struct writeback_control;
111 #if IS_ENABLED(CONFIG_FS_DAX)
112 int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk);
113 void dax_remove_host(struct gendisk *disk);
115 static inline void fs_put_dax(struct dax_device *dax_dev)
120 struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev,
122 int dax_writeback_mapping_range(struct address_space *mapping,
123 struct dax_device *dax_dev, struct writeback_control *wbc);
125 struct page *dax_layout_busy_page(struct address_space *mapping);
126 struct page *dax_layout_busy_page_range(struct address_space *mapping, loff_t start, loff_t end);
127 dax_entry_t dax_lock_page(struct page *page);
128 void dax_unlock_page(struct page *page, dax_entry_t cookie);
130 static inline int dax_add_host(struct dax_device *dax_dev, struct gendisk *disk)
134 static inline void dax_remove_host(struct gendisk *disk)
138 static inline void fs_put_dax(struct dax_device *dax_dev)
142 static inline struct dax_device *fs_dax_get_by_bdev(struct block_device *bdev,
148 static inline struct page *dax_layout_busy_page(struct address_space *mapping)
153 static inline struct page *dax_layout_busy_page_range(struct address_space *mapping, pgoff_t start, pgoff_t nr_pages)
158 static inline int dax_writeback_mapping_range(struct address_space *mapping,
159 struct dax_device *dax_dev, struct writeback_control *wbc)
164 static inline dax_entry_t dax_lock_page(struct page *page)
166 if (IS_DAX(page->mapping->host))
171 static inline void dax_unlock_page(struct page *page, dax_entry_t cookie)
176 int dax_zero_range(struct inode *inode, loff_t pos, loff_t len, bool *did_zero,
177 const struct iomap_ops *ops);
178 int dax_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,
179 const struct iomap_ops *ops);
181 #if IS_ENABLED(CONFIG_DAX)
182 int dax_read_lock(void);
183 void dax_read_unlock(int id);
185 static inline int dax_read_lock(void)
190 static inline void dax_read_unlock(int id)
193 #endif /* CONFIG_DAX */
194 bool dax_alive(struct dax_device *dax_dev);
195 void *dax_get_private(struct dax_device *dax_dev);
196 long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages,
197 void **kaddr, pfn_t *pfn);
198 size_t dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
199 size_t bytes, struct iov_iter *i);
200 size_t dax_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff, void *addr,
201 size_t bytes, struct iov_iter *i);
202 int dax_zero_page_range(struct dax_device *dax_dev, pgoff_t pgoff,
204 void dax_flush(struct dax_device *dax_dev, void *addr, size_t size);
206 ssize_t dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter,
207 const struct iomap_ops *ops);
208 vm_fault_t dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size,
209 pfn_t *pfnp, int *errp, const struct iomap_ops *ops);
210 vm_fault_t dax_finish_sync_fault(struct vm_fault *vmf,
211 enum page_entry_size pe_size, pfn_t pfn);
212 int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
213 int dax_invalidate_mapping_entry_sync(struct address_space *mapping,
215 static inline bool dax_mapping(struct address_space *mapping)
217 return mapping->host && IS_DAX(mapping->host);
220 #ifdef CONFIG_DEV_DAX_HMEM_DEVICES
221 void hmem_register_device(int target_nid, struct resource *r);
223 static inline void hmem_register_device(int target_nid, struct resource *r)