1 /* SPDX-License-Identifier: GPL-2.0 */
3 #define LINUX_IOMAP_H 1
5 #include <linux/types.h>
7 struct fiemap_extent_info
;
11 struct vm_area_struct
;
15 * Types of block ranges for iomap mappings:
17 #define IOMAP_HOLE 0x01 /* no blocks allocated, need allocation */
18 #define IOMAP_DELALLOC 0x02 /* delayed allocation blocks */
19 #define IOMAP_MAPPED 0x03 /* blocks allocated @blkno */
20 #define IOMAP_UNWRITTEN 0x04 /* blocks allocated @blkno in unwritten state */
23 * Flags for all iomap mappings:
25 #define IOMAP_F_NEW 0x01 /* blocks have been newly allocated */
28 * Flags that only need to be reported for IOMAP_REPORT requests:
30 #define IOMAP_F_MERGED 0x10 /* contains multiple blocks/extents */
31 #define IOMAP_F_SHARED 0x20 /* block shared with another file */
34 * Magic value for blkno:
36 #define IOMAP_NULL_BLOCK -1LL /* blkno is not valid */
39 sector_t blkno
; /* 1st sector of mapping, 512b units */
40 loff_t offset
; /* file offset of mapping, bytes */
41 u64 length
; /* length of mapping, bytes */
42 u16 type
; /* type of mapping */
43 u16 flags
; /* flags for mapping */
44 struct block_device
*bdev
; /* block device for I/O */
45 struct dax_device
*dax_dev
; /* dax_dev for dax operations */
49 * Flags for iomap_begin / iomap_end. No flag implies a read.
51 #define IOMAP_WRITE (1 << 0) /* writing, must allocate blocks */
52 #define IOMAP_ZERO (1 << 1) /* zeroing operation, may skip holes */
53 #define IOMAP_REPORT (1 << 2) /* report extent status, e.g. FIEMAP */
54 #define IOMAP_FAULT (1 << 3) /* mapping for page fault */
55 #define IOMAP_DIRECT (1 << 4) /* direct I/O */
56 #define IOMAP_NOWAIT (1 << 5) /* Don't wait for writeback */
60 * Return the existing mapping at pos, or reserve space starting at
61 * pos for up to length, as long as we can do it as a single mapping.
62 * The actual length is returned in iomap->length.
64 int (*iomap_begin
)(struct inode
*inode
, loff_t pos
, loff_t length
,
65 unsigned flags
, struct iomap
*iomap
);
68 * Commit and/or unreserve space previous allocated using iomap_begin.
69 * Written indicates the length of the successful write operation which
70 * needs to be commited, while the rest needs to be unreserved.
71 * Written might be zero if no data was written.
73 int (*iomap_end
)(struct inode
*inode
, loff_t pos
, loff_t length
,
74 ssize_t written
, unsigned flags
, struct iomap
*iomap
);
77 ssize_t
iomap_file_buffered_write(struct kiocb
*iocb
, struct iov_iter
*from
,
78 const struct iomap_ops
*ops
);
79 int iomap_file_dirty(struct inode
*inode
, loff_t pos
, loff_t len
,
80 const struct iomap_ops
*ops
);
81 int iomap_zero_range(struct inode
*inode
, loff_t pos
, loff_t len
,
82 bool *did_zero
, const struct iomap_ops
*ops
);
83 int iomap_truncate_page(struct inode
*inode
, loff_t pos
, bool *did_zero
,
84 const struct iomap_ops
*ops
);
85 int iomap_page_mkwrite(struct vm_fault
*vmf
, const struct iomap_ops
*ops
);
86 int iomap_fiemap(struct inode
*inode
, struct fiemap_extent_info
*fieinfo
,
87 loff_t start
, loff_t len
, const struct iomap_ops
*ops
);
88 loff_t
iomap_seek_hole(struct inode
*inode
, loff_t offset
,
89 const struct iomap_ops
*ops
);
90 loff_t
iomap_seek_data(struct inode
*inode
, loff_t offset
,
91 const struct iomap_ops
*ops
);
94 * Flags for direct I/O ->end_io:
96 #define IOMAP_DIO_UNWRITTEN (1 << 0) /* covers unwritten extent(s) */
97 #define IOMAP_DIO_COW (1 << 1) /* covers COW extent(s) */
98 typedef int (iomap_dio_end_io_t
)(struct kiocb
*iocb
, ssize_t ret
,
100 ssize_t
iomap_dio_rw(struct kiocb
*iocb
, struct iov_iter
*iter
,
101 const struct iomap_ops
*ops
, iomap_dio_end_io_t end_io
);
103 #endif /* LINUX_IOMAP_H */