[mirror_ubuntu-bionic-kernel.git] / include / linux / iomap.h

#ifndef LINUX_IOMAP_H
#define LINUX_IOMAP_H 1

#include <linux/types.h>

struct fiemap_extent_info;
struct inode;
struct iov_iter;
struct kiocb;
struct vm_area_struct;
struct vm_fault;

/*
 * Types of block ranges for iomap mappings:
 */
#define IOMAP_HOLE	0x01	/* no blocks allocated, need allocation */
#define IOMAP_DELALLOC	0x02	/* delayed allocation blocks */
#define IOMAP_MAPPED	0x03	/* blocks allocated @blkno */
#define IOMAP_UNWRITTEN	0x04	/* blocks allocated @blkno in unwritten state */

/*
 * Flags for all iomap mappings:
 */
#define IOMAP_F_NEW	0x01	/* blocks have been newly allocated */

/*
 * Flags that only need to be reported for IOMAP_REPORT requests:
 */
#define IOMAP_F_MERGED	0x10	/* contains multiple blocks/extents */
#define IOMAP_F_SHARED	0x20	/* block shared with another file */

/*
 * Magic value for blkno:
 */
#define IOMAP_NULL_BLOCK -1LL	/* blkno is not valid */

struct iomap {
	sector_t		blkno;	/* 1st sector of mapping, 512b units */
	loff_t			offset;	/* file offset of mapping, bytes */
	u64			length;	/* length of mapping, bytes */
	u16			type;	/* type of mapping */
	u16			flags;	/* flags for mapping */
	struct block_device	*bdev;	/* block device for I/O */
};

/*
 * Flags for iomap_begin / iomap_end.  No flag implies a read.
 */
#define IOMAP_WRITE		(1 << 0) /* writing, must allocate blocks */
#define IOMAP_ZERO		(1 << 1) /* zeroing operation, may skip holes */
#define IOMAP_REPORT		(1 << 2) /* report extent status, e.g. FIEMAP */
#define IOMAP_FAULT		(1 << 3) /* mapping for page fault */

struct iomap_ops {
	/*
	 * Return the existing mapping at pos, or reserve space starting at
	 * pos for up to length, as long as we can do it as a single mapping.
	 * The actual length is returned in iomap->length.
	 */
	int (*iomap_begin)(struct inode *inode, loff_t pos, loff_t length,
			unsigned flags, struct iomap *iomap);

	/*
	 * Commit and/or unreserve space previous allocated using iomap_begin.
	 * Written indicates the length of the successful write operation which
	 * needs to be commited, while the rest needs to be unreserved.
	 * Written might be zero if no data was written.
	 */
	int (*iomap_end)(struct inode *inode, loff_t pos, loff_t length,
			ssize_t written, unsigned flags, struct iomap *iomap);
};

ssize_t iomap_file_buffered_write(struct kiocb *iocb, struct iov_iter *from,
		struct iomap_ops *ops);
int iomap_file_dirty(struct inode *inode, loff_t pos, loff_t len,
		struct iomap_ops *ops);
int iomap_zero_range(struct inode *inode, loff_t pos, loff_t len,
		bool *did_zero, struct iomap_ops *ops);
int iomap_truncate_page(struct inode *inode, loff_t pos, bool *did_zero,
		struct iomap_ops *ops);
int iomap_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf,
		struct iomap_ops *ops);
int iomap_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
		loff_t start, loff_t len, struct iomap_ops *ops);

#endif /* LINUX_IOMAP_H */
Commit	Line	Data
199a31c6 CH	1	#ifndef LINUX_IOMAP_H
	2	#define LINUX_IOMAP_H 1
	3
	4	#include <linux/types.h>
	5
8be9f564	6	struct fiemap_extent_info;
ae259a9c CH	7	struct inode;
	8	struct iov_iter;
	9	struct kiocb;
	10	struct vm_area_struct;
	11	struct vm_fault;
	12
	13	/*
	14	* Types of block ranges for iomap mappings:
	15	*/
199a31c6 CH	16	#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
17de0a9f	21	/*
d33fd776	22	* Flags for all iomap mappings:
17de0a9f	23	*/
d33fd776 CH	24	#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 */
17de0a9f	31
ae259a9c CH	32	/*
	33	* Magic value for blkno:
	34	*/
199a31c6 CH	35	#define IOMAP_NULL_BLOCK -1LL /* blkno is not valid */
	36
	37	struct iomap {
ae259a9c CH	38	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 */
17de0a9f CH	41	u16 type; /* type of mapping */
17de0a9f CH	42	u16 flags; /* flags for mapping */
ae259a9c CH	43	struct block_device bdev; / block device for I/O */
	44	};
	45
	46	/*
	47	* Flags for iomap_begin / iomap_end. No flag implies a read.
	48	*/
d33fd776 CH	49	#define IOMAP_WRITE (1 << 0) /* writing, must allocate blocks */
	50	#define IOMAP_ZERO (1 << 1) /* zeroing operation, may skip holes */
	51	#define IOMAP_REPORT (1 << 2) /* report extent status, e.g. FIEMAP */
9484ab1b	52	#define IOMAP_FAULT (1 << 3) /* mapping for page fault */
ae259a9c CH	53
	54	struct iomap_ops {
	55	/*
	56	* Return the existing mapping at pos, or reserve space starting at
	57	* pos for up to length, as long as we can do it as a single mapping.
	58	* The actual length is returned in iomap->length.
	59	*/
	60	int (iomap_begin)(struct inode inode, loff_t pos, loff_t length,
	61	unsigned flags, struct iomap *iomap);
	62
	63	/*
	64	* Commit and/or unreserve space previous allocated using iomap_begin.
	65	* Written indicates the length of the successful write operation which
	66	* needs to be commited, while the rest needs to be unreserved.
	67	* Written might be zero if no data was written.
	68	*/
	69	int (iomap_end)(struct inode inode, loff_t pos, loff_t length,
	70	ssize_t written, unsigned flags, struct iomap *iomap);
199a31c6 CH	71	};
199a31c6 CH	72
ae259a9c CH	73	ssize_t iomap_file_buffered_write(struct kiocb iocb, struct iov_iter from,
ae259a9c CH	74	struct iomap_ops *ops);
5f4e5752 CH	75	int iomap_file_dirty(struct inode *inode, loff_t pos, loff_t len,
5f4e5752 CH	76	struct iomap_ops *ops);
ae259a9c CH	77	int iomap_zero_range(struct inode *inode, loff_t pos, loff_t len,
	78	bool did_zero, struct iomap_ops ops);
	79	int iomap_truncate_page(struct inode inode, loff_t pos, bool did_zero,
	80	struct iomap_ops *ops);
	81	int iomap_page_mkwrite(struct vm_area_struct vma, struct vm_fault vmf,
	82	struct iomap_ops *ops);
8be9f564 CH	83	int iomap_fiemap(struct inode inode, struct fiemap_extent_info fieinfo,
8be9f564 CH	84	loff_t start, loff_t len, struct iomap_ops *ops);
ae259a9c	85
199a31c6	86	#endif /* LINUX_IOMAP_H */