https://github.com/torvalds/linux
Tip revision: 30a7acd573899fd8b8ac39236eff6468b195ac7d authored by Linus Torvalds on 31 December 2017, 22:47:43 UTC
Linux 4.15-rc6
Linux 4.15-rc6
Tip revision: 30a7acd
xfs_rmap_item.h
/*
* Copyright (C) 2016 Oracle. All Rights Reserved.
*
* Author: Darrick J. Wong <darrick.wong@oracle.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it would be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#ifndef __XFS_RMAP_ITEM_H__
#define __XFS_RMAP_ITEM_H__
/*
* There are (currently) three pairs of rmap btree redo item types: map, unmap,
* and convert. The common abbreviations for these are RUI (rmap update
* intent) and RUD (rmap update done). The redo item type is encoded in the
* flags field of each xfs_map_extent.
*
* *I items should be recorded in the *first* of a series of rolled
* transactions, and the *D items should be recorded in the same transaction
* that records the associated rmapbt updates. Typically, the first
* transaction will record a bmbt update, followed by some number of
* transactions containing rmapbt updates, and finally transactions with any
* bnobt/cntbt updates.
*
* Should the system crash after the commit of the first transaction but
* before the commit of the final transaction in a series, log recovery will
* use the redo information recorded by the intent items to replay the
* (rmapbt/bnobt/cntbt) metadata updates in the non-first transaction.
*/
/* kernel only RUI/RUD definitions */
struct xfs_mount;
struct kmem_zone;
/*
* Max number of extents in fast allocation path.
*/
#define XFS_RUI_MAX_FAST_EXTENTS 16
/*
* Define RUI flag bits. Manipulated by set/clear/test_bit operators.
*/
#define XFS_RUI_RECOVERED 1
/*
* This is the "rmap update intent" log item. It is used to log the fact that
* some reverse mappings need to change. It is used in conjunction with the
* "rmap update done" log item described below.
*
* These log items follow the same rules as struct xfs_efi_log_item; see the
* comments about that structure (in xfs_extfree_item.h) for more details.
*/
struct xfs_rui_log_item {
struct xfs_log_item rui_item;
atomic_t rui_refcount;
atomic_t rui_next_extent;
unsigned long rui_flags; /* misc flags */
struct xfs_rui_log_format rui_format;
};
static inline size_t
xfs_rui_log_item_sizeof(
unsigned int nr)
{
return offsetof(struct xfs_rui_log_item, rui_format) +
xfs_rui_log_format_sizeof(nr);
}
/*
* This is the "rmap update done" log item. It is used to log the fact that
* some rmapbt updates mentioned in an earlier rui item have been performed.
*/
struct xfs_rud_log_item {
struct xfs_log_item rud_item;
struct xfs_rui_log_item *rud_ruip;
struct xfs_rud_log_format rud_format;
};
extern struct kmem_zone *xfs_rui_zone;
extern struct kmem_zone *xfs_rud_zone;
struct xfs_rui_log_item *xfs_rui_init(struct xfs_mount *, uint);
struct xfs_rud_log_item *xfs_rud_init(struct xfs_mount *,
struct xfs_rui_log_item *);
int xfs_rui_copy_format(struct xfs_log_iovec *buf,
struct xfs_rui_log_format *dst_rui_fmt);
void xfs_rui_item_free(struct xfs_rui_log_item *);
void xfs_rui_release(struct xfs_rui_log_item *);
int xfs_rui_recover(struct xfs_mount *mp, struct xfs_rui_log_item *ruip);
#endif /* __XFS_RMAP_ITEM_H__ */