76 lines
2.6 KiB
C
76 lines
2.6 KiB
C
|
// 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
|
||
|
|
|
||
|
|
/*
|
||
|
|
* 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.
|
||
|
|
*/
|
||
|
|
struct xfs_efi_log_item {
|
||
|
|
struct xfs_log_item efi_item;
|
||
|
|
atomic_t efi_refcount;
|
||
|
|
atomic_t efi_next_extent;
|
||
|
|
xfs_efi_log_format_t efi_format;
|
||
|
|
};
|
||
|
|
|
||
|
|
/*
|
||
|
|
* 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.
|
||
|
|
*/
|
||
|
|
struct xfs_efd_log_item {
|
||
|
|
struct xfs_log_item efd_item;
|
||
|
|
struct xfs_efi_log_item *efd_efip;
|
||
|
|
uint efd_next_extent;
|
||
|
|
xfs_efd_log_format_t efd_format;
|
||
|
|
};
|
||
|
|
|
||
|
|
/*
|
||
|
|
* 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;
|
||
|
|
|
||
|
|
#endif /* __XFS_EXTFREE_ITEM_H__ */
|