cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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xfs_refcount_item.h (2240B)

      1// SPDX-License-Identifier: GPL-2.0+
      2/*
      3 * Copyright (C) 2016 Oracle.  All Rights Reserved.
      4 * Author: Darrick J. Wong <darrick.wong@oracle.com>
      5 */
      6#ifndef	__XFS_REFCOUNT_ITEM_H__
      7#define	__XFS_REFCOUNT_ITEM_H__
      8
      9/*
     10 * There are (currently) two pairs of refcount btree redo item types:
     11 * increase and decrease.  The log items for these are CUI (refcount
     12 * update intent) and CUD (refcount update done).  The redo item type
     13 * is encoded in the flags field of each xfs_map_extent.
     14 *
     15 * *I items should be recorded in the *first* of a series of rolled
     16 * transactions, and the *D items should be recorded in the same
     17 * transaction that records the associated refcountbt updates.
     18 *
     19 * Should the system crash after the commit of the first transaction
     20 * but before the commit of the final transaction in a series, log
     21 * recovery will use the redo information recorded by the intent items
     22 * to replay the refcountbt metadata updates.
     23 */
     24
     25/* kernel only CUI/CUD definitions */
     26
     27struct xfs_mount;
     28struct kmem_cache;
     29
     30/*
     31 * Max number of extents in fast allocation path.
     32 */
     33#define	XFS_CUI_MAX_FAST_EXTENTS	16
     34
     35/*
     36 * This is the "refcount update intent" log item.  It is used to log
     37 * the fact that some reverse mappings need to change.  It is used in
     38 * conjunction with the "refcount update done" log item described
     39 * below.
     40 *
     41 * These log items follow the same rules as struct xfs_efi_log_item;
     42 * see the comments about that structure (in xfs_extfree_item.h) for
     43 * more details.
     44 */
     45struct xfs_cui_log_item {
     46	struct xfs_log_item		cui_item;
     47	atomic_t			cui_refcount;
     48	atomic_t			cui_next_extent;
     49	struct xfs_cui_log_format	cui_format;
     50};
     51
     52static inline size_t
     53xfs_cui_log_item_sizeof(
     54	unsigned int		nr)
     55{
     56	return offsetof(struct xfs_cui_log_item, cui_format) +
     57			xfs_cui_log_format_sizeof(nr);
     58}
     59
     60/*
     61 * This is the "refcount update done" log item.  It is used to log the
     62 * fact that some refcountbt updates mentioned in an earlier cui item
     63 * have been performed.
     64 */
     65struct xfs_cud_log_item {
     66	struct xfs_log_item		cud_item;
     67	struct xfs_cui_log_item		*cud_cuip;
     68	struct xfs_cud_log_format	cud_format;
     69};
     70
     71extern struct kmem_cache	*xfs_cui_cache;
     72extern struct kmem_cache	*xfs_cud_cache;
     73
     74#endif	/* __XFS_REFCOUNT_ITEM_H__ */