xref: /linux-6.15/include/linux/dax.h (revision 86effd0d)
1 #ifndef _LINUX_DAX_H
2 #define _LINUX_DAX_H
3 
4 #include <linux/fs.h>
5 #include <linux/mm.h>
6 #include <linux/radix-tree.h>
7 #include <asm/pgtable.h>
8 
9 /* We use lowest available exceptional entry bit for locking */
10 #define RADIX_DAX_ENTRY_LOCK (1 << RADIX_TREE_EXCEPTIONAL_SHIFT)
11 
12 ssize_t dax_do_io(struct kiocb *, struct inode *, struct iov_iter *,
13 		  get_block_t, dio_iodone_t, int flags);
14 int dax_zero_page_range(struct inode *, loff_t from, unsigned len, get_block_t);
15 int dax_truncate_page(struct inode *, loff_t from, get_block_t);
16 int dax_fault(struct vm_area_struct *, struct vm_fault *, get_block_t);
17 int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index);
18 void dax_wake_mapping_entry_waiter(struct address_space *mapping,
19 				   pgoff_t index, bool wake_all);
20 
21 #ifdef CONFIG_FS_DAX
22 struct page *read_dax_sector(struct block_device *bdev, sector_t n);
23 void dax_unlock_mapping_entry(struct address_space *mapping, pgoff_t index);
24 int __dax_zero_page_range(struct block_device *bdev, sector_t sector,
25 		unsigned int offset, unsigned int length);
26 #else
27 static inline struct page *read_dax_sector(struct block_device *bdev,
28 		sector_t n)
29 {
30 	return ERR_PTR(-ENXIO);
31 }
32 /* Shouldn't ever be called when dax is disabled. */
33 static inline void dax_unlock_mapping_entry(struct address_space *mapping,
34 					    pgoff_t index)
35 {
36 	BUG();
37 }
38 static inline int __dax_zero_page_range(struct block_device *bdev,
39 		sector_t sector, unsigned int offset, unsigned int length)
40 {
41 	return -ENXIO;
42 }
43 #endif
44 
45 #if defined(CONFIG_TRANSPARENT_HUGEPAGE)
46 int dax_pmd_fault(struct vm_area_struct *, unsigned long addr, pmd_t *,
47 				unsigned int flags, get_block_t);
48 #else
49 static inline int dax_pmd_fault(struct vm_area_struct *vma, unsigned long addr,
50 				pmd_t *pmd, unsigned int flags, get_block_t gb)
51 {
52 	return VM_FAULT_FALLBACK;
53 }
54 #endif
55 int dax_pfn_mkwrite(struct vm_area_struct *, struct vm_fault *);
56 #define dax_mkwrite(vma, vmf, gb)	dax_fault(vma, vmf, gb)
57 
58 static inline bool vma_is_dax(struct vm_area_struct *vma)
59 {
60 	return vma->vm_file && IS_DAX(vma->vm_file->f_mapping->host);
61 }
62 
63 static inline bool dax_mapping(struct address_space *mapping)
64 {
65 	return mapping->host && IS_DAX(mapping->host);
66 }
67 
68 struct writeback_control;
69 int dax_writeback_mapping_range(struct address_space *mapping,
70 		struct block_device *bdev, struct writeback_control *wbc);
71 #endif
72