| quotactl(2) | System Calls Manual | quotactl(2) |
quotactl - manipulate disk quotas
Standard C library (libc, -lc)
#include <sys/quota.h>
#include <xfs/xqm.h> /* Definition of Q_X* and XFS_QUOTA_* constants
(or <linux/dqblk_xfs.h>; see NOTES) */
int quotactl(int op, const char *_Nullable special, int id,
caddr_t addr);
The quota system can be used to set per-user, per-group, and per-project limits on the amount of disk space used on a filesystem. For each user and/or group, a soft limit and a hard limit can be set for each filesystem. The hard limit can't be exceeded. The soft limit can be exceeded, but warnings will ensue. Moreover, the user can't exceed the soft limit for more than grace period duration (one week by default) at a time; after this, the soft limit counts as a hard limit.
The quotactl() call manipulates disk quotas. The op argument indicates an operation to be applied to the user or group ID specified in id. To initialize the op argument, use the QCMD(subop, type) macro. The type value is either USRQUOTA, for user quotas, GRPQUOTA, for group quotas, or (since Linux 4.1) PRJQUOTA, for project quotas. The subop value is described below.
The special argument is a pointer to a null-terminated string containing the pathname of the (mounted) block special device for the filesystem being manipulated.
The addr argument is the address of an optional, operation-specific, data structure that is copied in or out of the system. The interpretation of addr is given with each operation below.
The subop value is one of the following operations:
/* uint64_t is an unsigned 64-bit integer;
uint32_t is an unsigned 32-bit integer */
struct dqblk { /* Definition since Linux 2.4.22 */
uint64_t dqb_bhardlimit; /* Absolute limit on disk
quota blocks alloc */
uint64_t dqb_bsoftlimit; /* Preferred limit on
disk quota blocks */
uint64_t dqb_curspace; /* Current occupied space
(in bytes) */
uint64_t dqb_ihardlimit; /* Maximum number of
allocated inodes */
uint64_t dqb_isoftlimit; /* Preferred inode limit */
uint64_t dqb_curinodes; /* Current number of
allocated inodes */
uint64_t dqb_btime; /* Time limit for excessive
disk use */
uint64_t dqb_itime; /* Time limit for excessive
files */
uint32_t dqb_valid; /* Bit mask of QIF_*
constants */
};
/* Flags in dqb_valid that indicate which fields in
dqblk structure are valid. */
#define QIF_BLIMITS 1
#define QIF_SPACE 2
#define QIF_ILIMITS 4
#define QIF_INODES 8
#define QIF_BTIME 16
#define QIF_ITIME 32
#define QIF_LIMITS (QIF_BLIMITS | QIF_ILIMITS)
#define QIF_USAGE (QIF_SPACE | QIF_INODES)
#define QIF_TIMES (QIF_BTIME | QIF_ITIME)
#define QIF_ALL (QIF_LIMITS | QIF_USAGE | QIF_TIMES)
struct nextdqblk {
uint64_t dqb_bhardlimit;
uint64_t dqb_bsoftlimit;
uint64_t dqb_curspace;
uint64_t dqb_ihardlimit;
uint64_t dqb_isoftlimit;
uint64_t dqb_curinodes;
uint64_t dqb_btime;
uint64_t dqb_itime;
uint32_t dqb_valid;
uint32_t dqb_id;
};
/* uint64_t is an unsigned 64-bit integer;
uint32_t is an unsigned 32-bit integer */
struct dqinfo { /* Defined since Linux 2.4.22 */
uint64_t dqi_bgrace; /* Time before block soft limit
becomes hard limit */
uint64_t dqi_igrace; /* Time before inode soft limit
becomes hard limit */
uint32_t dqi_flags; /* Flags for quotafile
(DQF_*) */
uint32_t dqi_valid;
};
/* Bits for dqi_flags */
/* Quota format QFMT_VFS_OLD */
#define DQF_ROOT_SQUASH (1 << 0) /* Root squash enabled */
/* Before Linux v4.0, this had been defined
privately as V1_DQF_RSQUASH */
/* Quota format QFMT_VFS_V0 / QFMT_VFS_V1 */
#define DQF_SYS_FILE (1 << 16) /* Quota stored in
a system file */
/* Flags in dqi_valid that indicate which fields in
dqinfo structure are valid. */
#define IIF_BGRACE 1
#define IIF_IGRACE 2
#define IIF_FLAGS 4
#define IIF_ALL (IIF_BGRACE | IIF_IGRACE | IIF_FLAGS)
For XFS filesystems making use of the XFS Quota Manager (XQM), the above operations are bypassed and the following operations are used:
XFS_QUOTA_UDQ_ACCT /* User quota accounting */
XFS_QUOTA_UDQ_ENFD /* User quota limits enforcement */
XFS_QUOTA_GDQ_ACCT /* Group quota accounting */
XFS_QUOTA_GDQ_ENFD /* Group quota limits enforcement */
XFS_QUOTA_PDQ_ACCT /* Project quota accounting */
XFS_QUOTA_PDQ_ENFD /* Project quota limits enforcement */
/* All the blk units are in BBs (Basic Blocks) of
512 bytes. */
#define FS_DQUOT_VERSION 1 /* fs_disk_quota.d_version */
#define XFS_USER_QUOTA (1<<0) /* User quota type */
#define XFS_PROJ_QUOTA (1<<1) /* Project quota type */
#define XFS_GROUP_QUOTA (1<<2) /* Group quota type */
struct fs_disk_quota {
int8_t d_version; /* Version of this structure */
int8_t d_flags; /* XFS_{USER,PROJ,GROUP}_QUOTA */
uint16_t d_fieldmask; /* Field specifier */
uint32_t d_id; /* User, project, or group ID */
uint64_t d_blk_hardlimit; /* Absolute limit on
disk blocks */
uint64_t d_blk_softlimit; /* Preferred limit on
disk blocks */
uint64_t d_ino_hardlimit; /* Maximum # allocated
inodes */
uint64_t d_ino_softlimit; /* Preferred inode limit */
uint64_t d_bcount; /* # disk blocks owned by
the user */
uint64_t d_icount; /* # inodes owned by the user */
int32_t d_itimer; /* Zero if within inode limits */
/* If not, we refuse service */
int32_t d_btimer; /* Similar to above; for
disk blocks */
uint16_t d_iwarns; /* # warnings issued with
respect to # of inodes */
uint16_t d_bwarns; /* # warnings issued with
respect to disk blocks */
int32_t d_padding2; /* Padding - for future use */
uint64_t d_rtb_hardlimit; /* Absolute limit on realtime
(RT) disk blocks */
uint64_t d_rtb_softlimit; /* Preferred limit on RT
disk blocks */
uint64_t d_rtbcount; /* # realtime blocks owned */
int32_t d_rtbtimer; /* Similar to above; for RT
disk blocks */
uint16_t d_rtbwarns; /* # warnings issued with
respect to RT disk blocks */
int16_t d_padding3; /* Padding - for future use */
char d_padding4[8]; /* Yet more padding */
};
#define FS_QSTAT_VERSION 1 /* fs_quota_stat.qs_version */
struct fs_qfilestat {
uint64_t qfs_ino; /* Inode number */
uint64_t qfs_nblks; /* Number of BBs
512-byte-blocks */
uint32_t qfs_nextents; /* Number of extents */
};
struct fs_quota_stat {
int8_t qs_version; /* Version number for
future changes */
uint16_t qs_flags; /* XFS_QUOTA_{U,P,G}DQ_{ACCT,ENFD} */
int8_t qs_pad; /* Unused */
struct fs_qfilestat qs_uquota; /* User quota storage
information */
struct fs_qfilestat qs_gquota; /* Group quota storage
information */
uint32_t qs_incoredqs; /* Number of dquots in core */
int32_t qs_btimelimit; /* Limit for blocks timer */
int32_t qs_itimelimit; /* Limit for inodes timer */
int32_t qs_rtbtimelimit;/* Limit for RT
blocks timer */
uint16_t qs_bwarnlimit; /* Limit for # of warnings */
uint16_t qs_iwarnlimit; /* Limit for # of warnings */
};
#define FS_QSTATV_VERSION1 1 /* fs_quota_statv.qs_version */
struct fs_qfilestatv {
uint64_t qfs_ino; /* Inode number */
uint64_t qfs_nblks; /* Number of BBs
512-byte-blocks */
uint32_t qfs_nextents; /* Number of extents */
uint32_t qfs_pad; /* Pad for 8-byte alignment */
};
struct fs_quota_statv {
int8_t qs_version; /* Version for future
changes */
uint8_t qs_pad1; /* Pad for 16-bit alignment */
uint16_t qs_flags; /* XFS_QUOTA_.* flags */
uint32_t qs_incoredqs; /* Number of dquots incore */
struct fs_qfilestatv qs_uquota; /* User quota
information */
struct fs_qfilestatv qs_gquota; /* Group quota
information */
struct fs_qfilestatv qs_pquota; /* Project quota
information */
int32_t qs_btimelimit; /* Limit for blocks timer */
int32_t qs_itimelimit; /* Limit for inodes timer */
int32_t qs_rtbtimelimit; /* Limit for RT blocks
timer */
uint16_t qs_bwarnlimit; /* Limit for # of warnings */
uint16_t qs_iwarnlimit; /* Limit for # of warnings */
uint64_t qs_pad2[8]; /* For future proofing */
};
On success, quotactl() returns 0; on error -1 is returned, and errno is set to indicate the error.
Instead of <xfs/xqm.h> one can use <linux/dqblk_xfs.h>, taking into account that there are several naming discrepancies:
quota(1), getrlimit(2), quotacheck(8), quotaon(8)
| 2024-03-03 | Linux man-pages 6.7 |