Commit | Line | Data |
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c94c2acf MW |
1 | #ifndef _LINUX_DAX_H |
2 | #define _LINUX_DAX_H | |
3 | ||
4 | #include <linux/fs.h> | |
5 | #include <linux/mm.h> | |
4f622938 | 6 | #include <linux/radix-tree.h> |
c94c2acf MW |
7 | #include <asm/pgtable.h> |
8 | ||
a254e568 | 9 | struct iomap_ops; |
6568b08b DW |
10 | struct dax_device; |
11 | struct dax_operations { | |
12 | /* | |
13 | * direct_access: translate a device-relative | |
14 | * logical-page-offset into an absolute physical pfn. Return the | |
15 | * number of pages available for DAX at that pfn. | |
16 | */ | |
17 | long (*direct_access)(struct dax_device *, pgoff_t, long, | |
18 | void **, pfn_t *); | |
19 | }; | |
a254e568 | 20 | |
f5705aa8 DW |
21 | #if IS_ENABLED(CONFIG_DAX) |
22 | struct dax_device *dax_get_by_host(const char *host); | |
23 | void put_dax(struct dax_device *dax_dev); | |
24 | #else | |
25 | static inline struct dax_device *dax_get_by_host(const char *host) | |
26 | { | |
27 | return NULL; | |
28 | } | |
29 | ||
30 | static inline void put_dax(struct dax_device *dax_dev) | |
31 | { | |
32 | } | |
33 | #endif | |
34 | ||
ef510424 DW |
35 | int bdev_dax_pgoff(struct block_device *, sector_t, size_t, pgoff_t *pgoff); |
36 | #if IS_ENABLED(CONFIG_FS_DAX) | |
37 | int __bdev_dax_supported(struct super_block *sb, int blocksize); | |
38 | static inline int bdev_dax_supported(struct super_block *sb, int blocksize) | |
39 | { | |
40 | return __bdev_dax_supported(sb, blocksize); | |
41 | } | |
f5705aa8 DW |
42 | |
43 | static inline struct dax_device *fs_dax_get_by_host(const char *host) | |
44 | { | |
45 | return dax_get_by_host(host); | |
46 | } | |
47 | ||
48 | static inline void fs_put_dax(struct dax_device *dax_dev) | |
49 | { | |
50 | put_dax(dax_dev); | |
51 | } | |
52 | ||
ef510424 DW |
53 | #else |
54 | static inline int bdev_dax_supported(struct super_block *sb, int blocksize) | |
55 | { | |
56 | return -EOPNOTSUPP; | |
57 | } | |
ef510424 | 58 | |
f5705aa8 | 59 | static inline struct dax_device *fs_dax_get_by_host(const char *host) |
ef510424 DW |
60 | { |
61 | return NULL; | |
62 | } | |
63 | ||
f5705aa8 | 64 | static inline void fs_put_dax(struct dax_device *dax_dev) |
ef510424 DW |
65 | { |
66 | } | |
67 | #endif | |
68 | ||
7b6be844 DW |
69 | int dax_read_lock(void); |
70 | void dax_read_unlock(int id); | |
c1d6e828 DW |
71 | struct dax_device *alloc_dax(void *private, const char *host, |
72 | const struct dax_operations *ops); | |
c1d6e828 DW |
73 | bool dax_alive(struct dax_device *dax_dev); |
74 | void kill_dax(struct dax_device *dax_dev); | |
75 | void *dax_get_private(struct dax_device *dax_dev); | |
b0686260 DW |
76 | long dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, long nr_pages, |
77 | void **kaddr, pfn_t *pfn); | |
7b6be844 | 78 | |
fa28f729 | 79 | /* |
642261ac RZ |
80 | * We use lowest available bit in exceptional entry for locking, one bit for |
81 | * the entry size (PMD) and two more to tell us if the entry is a huge zero | |
82 | * page (HZP) or an empty entry that is just used for locking. In total four | |
83 | * special bits. | |
84 | * | |
85 | * If the PMD bit isn't set the entry has size PAGE_SIZE, and if the HZP and | |
86 | * EMPTY bits aren't set the entry is a normal DAX entry with a filesystem | |
87 | * block allocation. | |
fa28f729 | 88 | */ |
642261ac | 89 | #define RADIX_DAX_SHIFT (RADIX_TREE_EXCEPTIONAL_SHIFT + 4) |
e804315d | 90 | #define RADIX_DAX_ENTRY_LOCK (1 << RADIX_TREE_EXCEPTIONAL_SHIFT) |
642261ac RZ |
91 | #define RADIX_DAX_PMD (1 << (RADIX_TREE_EXCEPTIONAL_SHIFT + 1)) |
92 | #define RADIX_DAX_HZP (1 << (RADIX_TREE_EXCEPTIONAL_SHIFT + 2)) | |
93 | #define RADIX_DAX_EMPTY (1 << (RADIX_TREE_EXCEPTIONAL_SHIFT + 3)) | |
fa28f729 | 94 | |
642261ac RZ |
95 | static inline unsigned long dax_radix_sector(void *entry) |
96 | { | |
97 | return (unsigned long)entry >> RADIX_DAX_SHIFT; | |
98 | } | |
99 | ||
100 | static inline void *dax_radix_locked_entry(sector_t sector, unsigned long flags) | |
101 | { | |
102 | return (void *)(RADIX_TREE_EXCEPTIONAL_ENTRY | flags | | |
103 | ((unsigned long)sector << RADIX_DAX_SHIFT) | | |
104 | RADIX_DAX_ENTRY_LOCK); | |
105 | } | |
e804315d | 106 | |
11c59c92 | 107 | ssize_t dax_iomap_rw(struct kiocb *iocb, struct iov_iter *iter, |
8ff6daa1 | 108 | const struct iomap_ops *ops); |
c791ace1 DJ |
109 | int dax_iomap_fault(struct vm_fault *vmf, enum page_entry_size pe_size, |
110 | const struct iomap_ops *ops); | |
ac401cc7 | 111 | int dax_delete_mapping_entry(struct address_space *mapping, pgoff_t index); |
c6dcf52c JK |
112 | int dax_invalidate_mapping_entry_sync(struct address_space *mapping, |
113 | pgoff_t index); | |
ac401cc7 | 114 | void dax_wake_mapping_entry_waiter(struct address_space *mapping, |
63e95b5c | 115 | pgoff_t index, void *entry, bool wake_all); |
d1a5f2b4 DW |
116 | |
117 | #ifdef CONFIG_FS_DAX | |
cccbce67 DW |
118 | int __dax_zero_page_range(struct block_device *bdev, |
119 | struct dax_device *dax_dev, sector_t sector, | |
679c8bd3 | 120 | unsigned int offset, unsigned int length); |
d1a5f2b4 | 121 | #else |
679c8bd3 | 122 | static inline int __dax_zero_page_range(struct block_device *bdev, |
cccbce67 DW |
123 | struct dax_device *dax_dev, sector_t sector, |
124 | unsigned int offset, unsigned int length) | |
679c8bd3 CH |
125 | { |
126 | return -ENXIO; | |
127 | } | |
d1a5f2b4 DW |
128 | #endif |
129 | ||
642261ac RZ |
130 | #ifdef CONFIG_FS_DAX_PMD |
131 | static inline unsigned int dax_radix_order(void *entry) | |
132 | { | |
133 | if ((unsigned long)entry & RADIX_DAX_PMD) | |
134 | return PMD_SHIFT - PAGE_SHIFT; | |
135 | return 0; | |
136 | } | |
642261ac RZ |
137 | #else |
138 | static inline unsigned int dax_radix_order(void *entry) | |
139 | { | |
140 | return 0; | |
141 | } | |
642261ac | 142 | #endif |
11bac800 | 143 | int dax_pfn_mkwrite(struct vm_fault *vmf); |
c94c2acf | 144 | |
4897c765 MW |
145 | static inline bool vma_is_dax(struct vm_area_struct *vma) |
146 | { | |
147 | return vma->vm_file && IS_DAX(vma->vm_file->f_mapping->host); | |
148 | } | |
f9fe48be RZ |
149 | |
150 | static inline bool dax_mapping(struct address_space *mapping) | |
151 | { | |
152 | return mapping->host && IS_DAX(mapping->host); | |
153 | } | |
7f6d5b52 RZ |
154 | |
155 | struct writeback_control; | |
156 | int dax_writeback_mapping_range(struct address_space *mapping, | |
157 | struct block_device *bdev, struct writeback_control *wbc); | |
c94c2acf | 158 | #endif |