fs/xfs/libxfs/xfs_quota_defs.h

Source file repositories/reference/linux-study-clean/fs/xfs/libxfs/xfs_quota_defs.h

File Facts

System
Linux kernel
Corpus path
fs/xfs/libxfs/xfs_quota_defs.h
Extension
.h
Size
6436 bytes
Lines
188
Domain
Core OS
Bucket
VFS And Filesystem Core
Inferred role
Core OS: implementation source
Status
source implementation candidate

Why This File Exists

Core operating-system implementation surface: boot, tasks, memory, VFS, syscall-facing interfaces, synchronization, credentials, and isolation.

Dependency Surface

Detected Declarations

Annotated Snippet

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

/*
 * Quota definitions shared between user and kernel source trees.
 */

/*
 * Even though users may not have quota limits occupying all 64-bits,
 * they may need 64-bit accounting. Hence, 64-bit quota-counters,
 * and quota-limits. This is a waste in the common case, but hey ...
 */
typedef uint64_t	xfs_qcnt_t;

typedef uint8_t		xfs_dqtype_t;

#define XFS_DQTYPE_STRINGS \
	{ XFS_DQTYPE_USER,	"USER" }, \
	{ XFS_DQTYPE_PROJ,	"PROJ" }, \
	{ XFS_DQTYPE_GROUP,	"GROUP" }, \
	{ XFS_DQTYPE_BIGTIME,	"BIGTIME" }

/*
 * flags for q_flags field in the dquot.
 */
#define XFS_DQFLAG_DIRTY	(1u << 0)	/* dquot is dirty */

#define XFS_DQFLAG_STRINGS \
	{ XFS_DQFLAG_DIRTY,	"DIRTY" }

/*
 * We have the possibility of all three quota types being active at once, and
 * hence free space modification requires modification of all three current
 * dquots in a single transaction. For this case we need to have a reservation
 * of at least 3 dquots.
 *
 * However, a chmod operation can change both UID and GID in a single
 * transaction, resulting in requiring {old, new} x {uid, gid} dquots to be
 * modified. Hence for this case we need to reserve space for at least 4 dquots.
 *
 * And in the worst case, there's a rename operation that can be modifying up to
 * 4 inodes with dquots attached to them. In reality, the only inodes that can
 * have their dquots modified are the source and destination directory inodes
 * due to directory name creation and removal. That can require space allocation
 * and/or freeing on both directory inodes, and hence all three dquots on each
 * inode can be modified. And if the directories are world writeable, all the
 * dquots can be unique and so 6 dquots can be modified....
 *
 * And, of course, we also need to take into account the dquot log format item
 * used to describe each dquot.
 */
#define XFS_DQUOT_LOGRES	\
	((sizeof(struct xfs_dq_logformat) + sizeof(struct xfs_disk_dquot)) * 6)

#define XFS_IS_QUOTA_ON(mp)		((mp)->m_qflags & XFS_ALL_QUOTA_ACCT)
#define XFS_IS_UQUOTA_ON(mp)		((mp)->m_qflags & XFS_UQUOTA_ACCT)
#define XFS_IS_PQUOTA_ON(mp)		((mp)->m_qflags & XFS_PQUOTA_ACCT)
#define XFS_IS_GQUOTA_ON(mp)		((mp)->m_qflags & XFS_GQUOTA_ACCT)
#define XFS_IS_UQUOTA_ENFORCED(mp)	((mp)->m_qflags & XFS_UQUOTA_ENFD)
#define XFS_IS_GQUOTA_ENFORCED(mp)	((mp)->m_qflags & XFS_GQUOTA_ENFD)
#define XFS_IS_PQUOTA_ENFORCED(mp)	((mp)->m_qflags & XFS_PQUOTA_ENFD)

/*
 * Flags to tell various functions what to do. Not all of these are meaningful
 * to a single function. None of these XFS_QMOPT_* flags are meant to have
 * persistent values (ie. their values can and will change between versions)
 */
#define XFS_QMOPT_UQUOTA	(1u << 0) /* user dquot requested */
#define XFS_QMOPT_GQUOTA	(1u << 1) /* group dquot requested */
#define XFS_QMOPT_PQUOTA	(1u << 2) /* project dquot requested */
#define XFS_QMOPT_FORCE_RES	(1u << 3) /* ignore quota limits */
#define XFS_QMOPT_SBVERSION	(1u << 4) /* change superblock version num */

/*
 * flags to xfs_trans_mod_dquot to indicate which field needs to be
 * modified.
 */
#define XFS_QMOPT_RES_REGBLKS	(1u << 7)
#define XFS_QMOPT_RES_RTBLKS	(1u << 8)
#define XFS_QMOPT_BCOUNT	(1u << 9)
#define XFS_QMOPT_ICOUNT	(1u << 10)
#define XFS_QMOPT_RTBCOUNT	(1u << 11)
#define XFS_QMOPT_DELBCOUNT	(1u << 12)
#define XFS_QMOPT_DELRTBCOUNT	(1u << 13)
#define XFS_QMOPT_RES_INOS	(1u << 14)

Annotation

Implementation Notes