[linux.git] / fs / xfs / xfs_extfree_item.h

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2000,2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 */
#ifndef	__XFS_EXTFREE_ITEM_H__
#define	__XFS_EXTFREE_ITEM_H__

/* kernel only EFI/EFD definitions */

struct xfs_mount;
struct kmem_zone;

/*
 * Max number of extents in fast allocation path.
 */
#define	XFS_EFI_MAX_FAST_EXTENTS	16

/*
 * Define EFI flag bits. Manipulated by set/clear/test_bit operators.
 */
#define	XFS_EFI_RECOVERED	1

/*
 * This is the "extent free intention" log item.  It is used to log the fact
 * that some extents need to be free.  It is used in conjunction with the
 * "extent free done" log item described below.
 *
 * The EFI is reference counted so that it is not freed prior to both the EFI
 * and EFD being committed and unpinned. This ensures the EFI is inserted into
 * the AIL even in the event of out of order EFI/EFD processing. In other words,
 * an EFI is born with two references:
 *
 * 	1.) an EFI held reference to track EFI AIL insertion
 * 	2.) an EFD held reference to track EFD commit
 *
 * On allocation, both references are the responsibility of the caller. Once the
 * EFI is added to and dirtied in a transaction, ownership of reference one
 * transfers to the transaction. The reference is dropped once the EFI is
 * inserted to the AIL or in the event of failure along the way (e.g., commit
 * failure, log I/O error, etc.). Note that the caller remains responsible for
 * the EFD reference under all circumstances to this point. The caller has no
 * means to detect failure once the transaction is committed, however.
 * Therefore, an EFD is required after this point, even in the event of
 * unrelated failure.
 *
 * Once an EFD is allocated and dirtied in a transaction, reference two
 * transfers to the transaction. The EFD reference is dropped once it reaches
 * the unpin handler. Similar to the EFI, the reference also drops in the event
 * of commit failure or log I/O errors. Note that the EFD is not inserted in the
 * AIL, so at this point both the EFI and EFD are freed.
 */
typedef struct xfs_efi_log_item {
	xfs_log_item_t		efi_item;
	atomic_t		efi_refcount;
	atomic_t		efi_next_extent;
	unsigned long		efi_flags;	/* misc flags */
	xfs_efi_log_format_t	efi_format;
} xfs_efi_log_item_t;

/*
 * This is the "extent free done" log item.  It is used to log
 * the fact that some extents earlier mentioned in an efi item
 * have been freed.
 */
typedef struct xfs_efd_log_item {
	xfs_log_item_t		efd_item;
	xfs_efi_log_item_t	*efd_efip;
	uint			efd_next_extent;
	xfs_efd_log_format_t	efd_format;
} xfs_efd_log_item_t;

/*
 * Max number of extents in fast allocation path.
 */
#define	XFS_EFD_MAX_FAST_EXTENTS	16

extern struct kmem_zone	*xfs_efi_zone;
extern struct kmem_zone	*xfs_efd_zone;

xfs_efi_log_item_t	*xfs_efi_init(struct xfs_mount *, uint);
xfs_efd_log_item_t	*xfs_efd_init(struct xfs_mount *, xfs_efi_log_item_t *,
				      uint);
int			xfs_efi_copy_format(xfs_log_iovec_t *buf,
					    xfs_efi_log_format_t *dst_efi_fmt);
void			xfs_efi_item_free(xfs_efi_log_item_t *);
void			xfs_efi_release(struct xfs_efi_log_item *);

int			xfs_efi_recover(struct xfs_mount *mp,
					struct xfs_efi_log_item *efip);

#endif	/* __XFS_EXTFREE_ITEM_H__ */
Commit	Line	Data
0b61f8a4	1	// SPDX-License-Identifier: GPL-2.0
1da177e4	2	/*
7b718769 NS	3	* Copyright (c) 2000,2005 Silicon Graphics, Inc.
7b718769 NS	4	* All Rights Reserved.
1da177e4 LT	5	*/
	6	#ifndef __XFS_EXTFREE_ITEM_H__
	7	#define __XFS_EXTFREE_ITEM_H__
	8
9fbe24d9 DC	9	/* kernel only EFI/EFD definitions */
9fbe24d9 DC	10
1da177e4 LT	11	struct xfs_mount;
	12	struct kmem_zone;
	13
1da177e4 LT	14	/*
	15	* Max number of extents in fast allocation path.
	16	*/
	17	#define XFS_EFI_MAX_FAST_EXTENTS 16
	18
	19	/*
b199c8a4	20	* Define EFI flag bits. Manipulated by set/clear/test_bit operators.
1da177e4	21	*/
b199c8a4	22	#define XFS_EFI_RECOVERED 1
1da177e4 LT	23
1da177e4 LT	24	/*
666d644c DC	25	* This is the "extent free intention" log item. It is used to log the fact
	26	* that some extents need to be free. It is used in conjunction with the
	27	* "extent free done" log item described below.
	28	*
	29	* The EFI is reference counted so that it is not freed prior to both the EFI
8d99fe92 BF	30	* and EFD being committed and unpinned. This ensures the EFI is inserted into
	31	* the AIL even in the event of out of order EFI/EFD processing. In other words,
	32	* an EFI is born with two references:
	33	*
	34	* 1.) an EFI held reference to track EFI AIL insertion
	35	* 2.) an EFD held reference to track EFD commit
	36	*
	37	* On allocation, both references are the responsibility of the caller. Once the
	38	* EFI is added to and dirtied in a transaction, ownership of reference one
	39	* transfers to the transaction. The reference is dropped once the EFI is
	40	* inserted to the AIL or in the event of failure along the way (e.g., commit
	41	* failure, log I/O error, etc.). Note that the caller remains responsible for
	42	* the EFD reference under all circumstances to this point. The caller has no
	43	* means to detect failure once the transaction is committed, however.
	44	* Therefore, an EFD is required after this point, even in the event of
	45	* unrelated failure.
	46	*
	47	* Once an EFD is allocated and dirtied in a transaction, reference two
	48	* transfers to the transaction. The EFD reference is dropped once it reaches
	49	* the unpin handler. Similar to the EFI, the reference also drops in the event
	50	* of commit failure or log I/O errors. Note that the EFD is not inserted in the
	51	* AIL, so at this point both the EFI and EFD are freed.
1da177e4 LT	52	*/
	53	typedef struct xfs_efi_log_item {
	54	xfs_log_item_t efi_item;
666d644c	55	atomic_t efi_refcount;
b199c8a4 DC	56	atomic_t efi_next_extent;
b199c8a4 DC	57	unsigned long efi_flags; /* misc flags */
1da177e4 LT	58	xfs_efi_log_format_t efi_format;
	59	} xfs_efi_log_item_t;
	60
	61	/*
	62	* This is the "extent free done" log item. It is used to log
	63	* the fact that some extents earlier mentioned in an efi item
	64	* have been freed.
	65	*/
	66	typedef struct xfs_efd_log_item {
	67	xfs_log_item_t efd_item;
	68	xfs_efi_log_item_t *efd_efip;
	69	uint efd_next_extent;
	70	xfs_efd_log_format_t efd_format;
	71	} xfs_efd_log_item_t;
	72
	73	/*
	74	* Max number of extents in fast allocation path.
	75	*/
	76	#define XFS_EFD_MAX_FAST_EXTENTS 16
	77
	78	extern struct kmem_zone *xfs_efi_zone;
	79	extern struct kmem_zone *xfs_efd_zone;
	80
	81	xfs_efi_log_item_t xfs_efi_init(struct xfs_mount , uint);
	82	xfs_efd_log_item_t xfs_efd_init(struct xfs_mount , xfs_efi_log_item_t *,
	83	uint);
6d192a9b TS	84	int xfs_efi_copy_format(xfs_log_iovec_t *buf,
6d192a9b TS	85	xfs_efi_log_format_t *dst_efi_fmt);
7d795ca3	86	void xfs_efi_item_free(xfs_efi_log_item_t *);
5e4b5386	87	void xfs_efi_release(struct xfs_efi_log_item *);
7d795ca3	88
dc42375d DW	89	int xfs_efi_recover(struct xfs_mount *mp,
	90	struct xfs_efi_log_item *efip);
	91
1da177e4	92	#endif /* __XFS_EXTFREE_ITEM_H__ */