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 at @addr */
20 #define IOMAP_UNWRITTEN 0x04 /* blocks allocated at @addr in unwritten state */
23 * Flags for all iomap mappings:
25 #define IOMAP_F_NEW 0x01 /* blocks have been newly allocated */
26 #define IOMAP_F_BOUNDARY 0x02 /* mapping ends at metadata boundary */
29 * Flags that only need to be reported for IOMAP_REPORT requests:
31 #define IOMAP_F_MERGED 0x10 /* contains multiple blocks/extents */
32 #define IOMAP_F_SHARED 0x20 /* block shared with another file */
33 #define IOMAP_F_DATA_INLINE 0x40 /* data inline in the inode */
36 * Magic value for addr:
38 #define IOMAP_NULL_ADDR -1ULL /* addr is not valid */
41 u64 addr; /* disk offset of mapping, bytes */
42 loff_t offset; /* file offset of mapping, bytes */
43 u64 length; /* length of mapping, bytes */
44 u16 type; /* type of mapping */
45 u16 flags; /* flags for mapping */
46 struct block_device *bdev; /* block device for I/O */
47 struct dax_device *dax_dev; /* dax_dev for dax operations */
51 * Flags for iomap_begin / iomap_end. No flag implies a read.
53 #define IOMAP_WRITE (1 << 0) /* writing, must allocate blocks */
54 #define IOMAP_ZERO (1 << 1) /* zeroing operation, may skip holes */
55 #define IOMAP_REPORT (1 << 2) /* report extent status, e.g. FIEMAP */
56 #define IOMAP_FAULT (1 << 3) /* mapping for page fault */
57 #define IOMAP_DIRECT (1 << 4) /* direct I/O */
58 #define IOMAP_NOWAIT (1 << 5) /* Don't wait for writeback */
62 * Return the existing mapping at pos, or reserve space starting at
63 * pos for up to length, as long as we can do it as a single mapping.
64 * The actual length is returned in iomap->length.
66 int (*iomap_begin)(struct inode *inode, loff_t pos, loff_t length,
67 unsigned flags, struct iomap *iomap);
70 * Commit and/or unreserve space previous allocated using iomap_begin.
71 * Written indicates the length of the successful write operation which
72 * needs to be commited, while the rest needs to be unreserved.
73 * Written might be zero if no data was written.
75 int (*iomap_end)(struct inode *inode, loff_t pos, loff_t length,
76 ssize_t written, unsigned flags, struct iomap *iomap);
79 ssize_t iomap_file_buffered_write(struct kiocb *iocb, struct iov_iter *from,
80 const struct iomap_ops *ops);
81 int iomap_file_dirty(struct inode *inode, loff_t pos, loff_t len,
82 const struct iomap_ops *ops);
83 int iomap_zero_range(struct inode *inode, loff_t pos, loff_t len,
84 bool *did_zero, const struct iomap_ops *ops);
85 int iomap_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,
86 const struct iomap_ops *ops);
87 int iomap_page_mkwrite(struct vm_fault *vmf, const struct iomap_ops *ops);
88 int iomap_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
89 loff_t start, loff_t len, const struct iomap_ops *ops);
90 loff_t iomap_seek_hole(struct inode *inode, loff_t offset,
91 const struct iomap_ops *ops);
92 loff_t iomap_seek_data(struct inode *inode, loff_t offset,
93 const struct iomap_ops *ops);
96 * Flags for direct I/O ->end_io:
98 #define IOMAP_DIO_UNWRITTEN (1 << 0) /* covers unwritten extent(s) */
99 #define IOMAP_DIO_COW (1 << 1) /* covers COW extent(s) */
100 typedef int (iomap_dio_end_io_t)(struct kiocb *iocb, ssize_t ret,
102 ssize_t iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
103 const struct iomap_ops *ops, iomap_dio_end_io_t end_io);
105 #endif /* LINUX_IOMAP_H */