1 /* SPDX-License-Identifier: GPL-2.0 */
3 #define LINUX_IOMAP_H 1
5 #include <linux/atomic.h>
6 #include <linux/bitmap.h>
8 #include <linux/types.h>
9 #include <linux/mm_types.h>
12 struct fiemap_extent_info
;
17 struct vm_area_struct
;
21 * Types of block ranges for iomap mappings:
23 #define IOMAP_HOLE 0x01 /* no blocks allocated, need allocation */
24 #define IOMAP_DELALLOC 0x02 /* delayed allocation blocks */
25 #define IOMAP_MAPPED 0x03 /* blocks allocated at @addr */
26 #define IOMAP_UNWRITTEN 0x04 /* blocks allocated at @addr in unwritten state */
27 #define IOMAP_INLINE 0x05 /* data inline in the inode */
30 * Flags for all iomap mappings:
32 * IOMAP_F_DIRTY indicates the inode has uncommitted metadata needed to access
33 * written data and requires fdatasync to commit them to persistent storage.
35 #define IOMAP_F_NEW 0x01 /* blocks have been newly allocated */
36 #define IOMAP_F_DIRTY 0x02 /* uncommitted metadata */
37 #define IOMAP_F_BUFFER_HEAD 0x04 /* file system requires buffer heads */
40 * Flags that only need to be reported for IOMAP_REPORT requests:
42 #define IOMAP_F_MERGED 0x10 /* contains multiple blocks/extents */
43 #define IOMAP_F_SHARED 0x20 /* block shared with another file */
46 * Flags from 0x1000 up are for file system specific usage:
48 #define IOMAP_F_PRIVATE 0x1000
52 * Magic value for addr:
54 #define IOMAP_NULL_ADDR -1ULL /* addr is not valid */
57 u64 addr
; /* disk offset of mapping, bytes */
58 loff_t offset
; /* file offset of mapping, bytes */
59 u64 length
; /* length of mapping, bytes */
60 u16 type
; /* type of mapping */
61 u16 flags
; /* flags for mapping */
62 struct block_device
*bdev
; /* block device for I/O */
63 struct dax_device
*dax_dev
; /* dax_dev for dax operations */
65 void *private; /* filesystem private */
68 * Called when finished processing a page in the mapping returned in
69 * this iomap. At least for now this is only supported in the buffered
72 void (*page_done
)(struct inode
*inode
, loff_t pos
, unsigned copied
,
73 struct page
*page
, struct iomap
*iomap
);
77 * Flags for iomap_begin / iomap_end. No flag implies a read.
79 #define IOMAP_WRITE (1 << 0) /* writing, must allocate blocks */
80 #define IOMAP_ZERO (1 << 1) /* zeroing operation, may skip holes */
81 #define IOMAP_REPORT (1 << 2) /* report extent status, e.g. FIEMAP */
82 #define IOMAP_FAULT (1 << 3) /* mapping for page fault */
83 #define IOMAP_DIRECT (1 << 4) /* direct I/O */
84 #define IOMAP_NOWAIT (1 << 5) /* do not block */
88 * Return the existing mapping at pos, or reserve space starting at
89 * pos for up to length, as long as we can do it as a single mapping.
90 * The actual length is returned in iomap->length.
92 int (*iomap_begin
)(struct inode
*inode
, loff_t pos
, loff_t length
,
93 unsigned flags
, struct iomap
*iomap
);
96 * Commit and/or unreserve space previous allocated using iomap_begin.
97 * Written indicates the length of the successful write operation which
98 * needs to be commited, while the rest needs to be unreserved.
99 * Written might be zero if no data was written.
101 int (*iomap_end
)(struct inode
*inode
, loff_t pos
, loff_t length
,
102 ssize_t written
, unsigned flags
, struct iomap
*iomap
);
106 * Structure allocate for each page when block size < PAGE_SIZE to track
107 * sub-page uptodate status and I/O completions.
111 atomic_t write_count
;
112 DECLARE_BITMAP(uptodate
, PAGE_SIZE
/ 512);
115 static inline struct iomap_page
*to_iomap_page(struct page
*page
)
117 if (page_has_private(page
))
118 return (struct iomap_page
*)page_private(page
);
122 ssize_t
iomap_file_buffered_write(struct kiocb
*iocb
, struct iov_iter
*from
,
123 const struct iomap_ops
*ops
);
124 int iomap_readpage(struct page
*page
, const struct iomap_ops
*ops
);
125 int iomap_readpages(struct address_space
*mapping
, struct list_head
*pages
,
126 unsigned nr_pages
, const struct iomap_ops
*ops
);
127 int iomap_set_page_dirty(struct page
*page
);
128 int iomap_is_partially_uptodate(struct page
*page
, unsigned long from
,
129 unsigned long count
);
130 int iomap_releasepage(struct page
*page
, gfp_t gfp_mask
);
131 void iomap_invalidatepage(struct page
*page
, unsigned int offset
,
133 #ifdef CONFIG_MIGRATION
134 int iomap_migrate_page(struct address_space
*mapping
, struct page
*newpage
,
135 struct page
*page
, enum migrate_mode mode
);
137 #define iomap_migrate_page NULL
139 int iomap_file_dirty(struct inode
*inode
, loff_t pos
, loff_t len
,
140 const struct iomap_ops
*ops
);
141 int iomap_zero_range(struct inode
*inode
, loff_t pos
, loff_t len
,
142 bool *did_zero
, const struct iomap_ops
*ops
);
143 int iomap_truncate_page(struct inode
*inode
, loff_t pos
, bool *did_zero
,
144 const struct iomap_ops
*ops
);
145 vm_fault_t
iomap_page_mkwrite(struct vm_fault
*vmf
,
146 const struct iomap_ops
*ops
);
147 int iomap_fiemap(struct inode
*inode
, struct fiemap_extent_info
*fieinfo
,
148 loff_t start
, loff_t len
, const struct iomap_ops
*ops
);
149 loff_t
iomap_seek_hole(struct inode
*inode
, loff_t offset
,
150 const struct iomap_ops
*ops
);
151 loff_t
iomap_seek_data(struct inode
*inode
, loff_t offset
,
152 const struct iomap_ops
*ops
);
153 sector_t
iomap_bmap(struct address_space
*mapping
, sector_t bno
,
154 const struct iomap_ops
*ops
);
157 * Flags for direct I/O ->end_io:
159 #define IOMAP_DIO_UNWRITTEN (1 << 0) /* covers unwritten extent(s) */
160 #define IOMAP_DIO_COW (1 << 1) /* covers COW extent(s) */
161 typedef int (iomap_dio_end_io_t
)(struct kiocb
*iocb
, ssize_t ret
,
163 ssize_t
iomap_dio_rw(struct kiocb
*iocb
, struct iov_iter
*iter
,
164 const struct iomap_ops
*ops
, iomap_dio_end_io_t end_io
);
168 struct swap_info_struct
;
170 int iomap_swapfile_activate(struct swap_info_struct
*sis
,
171 struct file
*swap_file
, sector_t
*pagespan
,
172 const struct iomap_ops
*ops
);
174 # define iomap_swapfile_activate(sis, swapfile, pagespan, ops) (-EIO)
175 #endif /* CONFIG_SWAP */
177 #endif /* LINUX_IOMAP_H */