blob: 69f4e9470084b7e98288deb0bc45cae59bd8477f [file] [log] [blame]
Christoph Hellwig199a31c2016-06-21 09:22:39 +10001#ifndef LINUX_IOMAP_H
2#define LINUX_IOMAP_H 1
3
4#include <linux/types.h>
5
Christoph Hellwig8be9f562016-06-21 09:38:45 +10006struct fiemap_extent_info;
Christoph Hellwigae259a92016-06-21 09:23:11 +10007struct inode;
8struct iov_iter;
9struct kiocb;
10struct vm_area_struct;
11struct vm_fault;
12
13/*
14 * Types of block ranges for iomap mappings:
15 */
Christoph Hellwig199a31c2016-06-21 09:22:39 +100016#define IOMAP_HOLE 0x01 /* no blocks allocated, need allocation */
17#define IOMAP_DELALLOC 0x02 /* delayed allocation blocks */
18#define IOMAP_MAPPED 0x03 /* blocks allocated @blkno */
19#define IOMAP_UNWRITTEN 0x04 /* blocks allocated @blkno in unwritten state */
20
Christoph Hellwigae259a92016-06-21 09:23:11 +100021/*
Christoph Hellwigd33fd772016-10-20 15:51:28 +110022 * Flags for all iomap mappings:
Christoph Hellwig17de0a92016-08-29 11:33:58 +100023 */
Christoph Hellwigd33fd772016-10-20 15:51:28 +110024#define IOMAP_F_NEW 0x01 /* blocks have been newly allocated */
25
26/*
27 * Flags that only need to be reported for IOMAP_REPORT requests:
28 */
29#define IOMAP_F_MERGED 0x10 /* contains multiple blocks/extents */
30#define IOMAP_F_SHARED 0x20 /* block shared with another file */
Christoph Hellwig17de0a92016-08-29 11:33:58 +100031
32/*
Christoph Hellwigae259a92016-06-21 09:23:11 +100033 * Magic value for blkno:
34 */
Christoph Hellwig199a31c2016-06-21 09:22:39 +100035#define IOMAP_NULL_BLOCK -1LL /* blkno is not valid */
36
37struct iomap {
Christoph Hellwigae259a92016-06-21 09:23:11 +100038 sector_t blkno; /* 1st sector of mapping, 512b units */
39 loff_t offset; /* file offset of mapping, bytes */
40 u64 length; /* length of mapping, bytes */
Christoph Hellwig17de0a92016-08-29 11:33:58 +100041 u16 type; /* type of mapping */
42 u16 flags; /* flags for mapping */
Christoph Hellwigae259a92016-06-21 09:23:11 +100043 struct block_device *bdev; /* block device for I/O */
Dan Williamsfa5d9322017-01-27 12:04:59 -080044 struct dax_device *dax_dev; /* dax_dev for dax operations */
Christoph Hellwig199a31c2016-06-21 09:22:39 +100045};
46
Christoph Hellwigae259a92016-06-21 09:23:11 +100047/*
48 * Flags for iomap_begin / iomap_end. No flag implies a read.
49 */
Christoph Hellwigd33fd772016-10-20 15:51:28 +110050#define IOMAP_WRITE (1 << 0) /* writing, must allocate blocks */
51#define IOMAP_ZERO (1 << 1) /* zeroing operation, may skip holes */
52#define IOMAP_REPORT (1 << 2) /* report extent status, e.g. FIEMAP */
Jan Kara9484ab12016-11-10 10:26:50 +110053#define IOMAP_FAULT (1 << 3) /* mapping for page fault */
Christoph Hellwigff6a9292016-11-30 14:36:01 +110054#define IOMAP_DIRECT (1 << 4) /* direct I/O */
Goldwyn Rodriguesa38d1242017-06-20 07:05:45 -050055#define IOMAP_NOWAIT (1 << 5) /* Don't wait for writeback */
Christoph Hellwigae259a92016-06-21 09:23:11 +100056
57struct iomap_ops {
58 /*
59 * Return the existing mapping at pos, or reserve space starting at
60 * pos for up to length, as long as we can do it as a single mapping.
61 * The actual length is returned in iomap->length.
62 */
63 int (*iomap_begin)(struct inode *inode, loff_t pos, loff_t length,
64 unsigned flags, struct iomap *iomap);
65
66 /*
67 * Commit and/or unreserve space previous allocated using iomap_begin.
68 * Written indicates the length of the successful write operation which
69 * needs to be commited, while the rest needs to be unreserved.
70 * Written might be zero if no data was written.
71 */
72 int (*iomap_end)(struct inode *inode, loff_t pos, loff_t length,
73 ssize_t written, unsigned flags, struct iomap *iomap);
74};
75
76ssize_t iomap_file_buffered_write(struct kiocb *iocb, struct iov_iter *from,
Christoph Hellwig8ff6daa2017-01-27 23:20:26 -080077 const struct iomap_ops *ops);
Christoph Hellwig5f4e5752016-09-19 10:12:45 +100078int iomap_file_dirty(struct inode *inode, loff_t pos, loff_t len,
Christoph Hellwig8ff6daa2017-01-27 23:20:26 -080079 const struct iomap_ops *ops);
Christoph Hellwigae259a92016-06-21 09:23:11 +100080int iomap_zero_range(struct inode *inode, loff_t pos, loff_t len,
Christoph Hellwig8ff6daa2017-01-27 23:20:26 -080081 bool *did_zero, const struct iomap_ops *ops);
Christoph Hellwigae259a92016-06-21 09:23:11 +100082int iomap_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,
Christoph Hellwig8ff6daa2017-01-27 23:20:26 -080083 const struct iomap_ops *ops);
Dave Jiang11bac802017-02-24 14:56:41 -080084int iomap_page_mkwrite(struct vm_fault *vmf, const struct iomap_ops *ops);
Christoph Hellwig8be9f562016-06-21 09:38:45 +100085int iomap_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
Christoph Hellwig8ff6daa2017-01-27 23:20:26 -080086 loff_t start, loff_t len, const struct iomap_ops *ops);
Christoph Hellwigae259a92016-06-21 09:23:11 +100087
Christoph Hellwigff6a9292016-11-30 14:36:01 +110088/*
89 * Flags for direct I/O ->end_io:
90 */
91#define IOMAP_DIO_UNWRITTEN (1 << 0) /* covers unwritten extent(s) */
92#define IOMAP_DIO_COW (1 << 1) /* covers COW extent(s) */
93typedef int (iomap_dio_end_io_t)(struct kiocb *iocb, ssize_t ret,
94 unsigned flags);
95ssize_t iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
Christoph Hellwig8ff6daa2017-01-27 23:20:26 -080096 const struct iomap_ops *ops, iomap_dio_end_io_t end_io);
Christoph Hellwigff6a9292016-11-30 14:36:01 +110097
Christoph Hellwig199a31c2016-06-21 09:22:39 +100098#endif /* LINUX_IOMAP_H */