GNU/Linux |
CentOS 2.1AS(Slurm) |
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quotactl(2) |
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quotactl − manipulate disk quotas
#include
<linux/quota.h>
#include <xfs/xqm.h>
long quotactl(int cmd, char ∗special, qid_t id, caddr_t addr)
The quotactl() call manipulates disk quotas. cmd indicates a command to be applied to UID id or GID id. To set the type of quota use the QCMD(cmd, type) macro. special is a pointer to a null-terminated string containing the path name of the block special device for the filesystem being manipulated. addr is the address of an optional, command specific, data structure which is copied in or out of the system. The interpretation of addr is given with each command below.
Q_QUOTAON |
Turn on quotas for a filesystem. addr points to the path name of file containing the quotas for the filesystem. The quota file must exist; it is normally created with the quotacheck(8) program. This call is restricted to the super-user. | ||
Q_QUOTAOFF |
Turn off quotas for a filesystem. addr and id are ignored. This call is restricted to the super-user. | ||
Q_GETQUOTA |
Get disk quota limits and current usage for user or group id. addr is a pointer to a mem_dqblk structure (defined in <linux/quota.h>). Only the super-user may get the quotas of a user other than himself. | ||
Q_SETQUOTA |
Set disk quota limits and current usage for user or group id. addr is a pointer to a mem_dqblk structure (defined in <linux/quota.h>). This call is restricted to the super-user. | ||
Q_SETQLIM |
Set disk quota limits for user or group id. addr is a pointer to a mem_dqblk structure (defined in <linux/quota.h>). This call is restricted to the super-user. | ||
Q_SETUSE |
Set current usage for user or group id. addr is a pointer to a mem_dqblk structure (defined in <linux/quota.h>). This call is restricted to the super-user. | ||
Q_SYNC |
Update the on-disk copy of quota usages for a filesystem. If special is null then all filesystems with active quotas are sync’ed. addr and id are ignored. | ||
Q_GETSTATS |
Get statistics and other generic information about quota subsystem. addr should be a pointer to dqstats structure (defined in <linux/quota.h>) in which data should be stored. special and id are ignored. |
New quota format also allows following additional calls:
Q_GETINFO |
Get information (like grace times) about quotafile. addr should be a pointer to mem_dqinfo structure (defined in <linux/quota.h>). id is ignored. | ||
Q_SETINFO |
Set information about quotafile. addr should be a pointer to mem_dqinfo structure (defined in <linux/quota.h>). id is ignored. This operation is restricted to super-user. | ||
Q_SETGRACE |
Set grace times in information about quotafile. addr should be a pointer to mem_dqinfo structure (defined in <linux/quota.h>). id is ignored. This operation is restricted to super-user. | ||
Q_SETFLAGS |
Set flags in information about quotafile. These flags are defined in <linux/quota.h>. Note that there are currently no defined flags. addr should be a pointer to mem_dqinfo structure (defined in <linux/quota.h>). id is ignored. This operation is restricted to super-user. |
For XFS filesystems making use
of the XFS Quota Manager (XQM), the
above commands are bypassed and the following commands are
used:
Q_XQUOTAON |
Turn on quotas for an XFS filesystem. XFS provides the ability to turn on/off quota limit enforcement with quota accounting. Therefore, XFS expects the addr to be a pointer to an unsigned int that contains either the flags XFS_QUOTA_UDQ_ACCT and/or XFS_QUOTA_UDQ_ENFD (for user quota), or XFS_QUOTA_GDQ_ACCT and/or XFS_QUOTA_GDQ_ENFD (for group quota), as defined in <xfs/xqm.h>. This call is restricted to the superuser. | ||
Q_XQUOTAOFF |
Turn off quotas for an XFS filesystem. As in Q_QUOTAON, XFS filesystems expect a pointer to an unsigned int that specifies whether quota accounting and/or limit enforcement need to be turned off. This call is restricted to the superuser. | ||
Q_XGETQUOTA |
Get disk quota limits and current usage for user id. addr is a pointer to a fs_disk_quota structure (defined in <xfs/xqm.h>). Only the superuser may get the quotas of a user other than himself. | ||
Q_XSETQLIM |
Set disk quota limits for user id. addr is a pointer to a fs_disk_quota structure (defined in <xfs/xqm.h>). This call is restricted to the superuser. | ||
Q_XGETQSTAT |
Returns a fs_quota_stat structure containing XFS filesystem specific quota information. This is useful in finding out how much space is spent to store quota information, and also to get quotaon/off status of a given local XFS filesystem. | ||
Q_XQUOTARM |
Free the disk space taken by disk quotas. Quotas must have already been turned off. |
There is no command equivalent to Q_SYNC for XFS since sync(1) writes quota information to disk (in addition to the other filesystem metadata it writes out).
quotactl() returns:
0 |
on success. |
|||
−1 |
on failure and sets errno to indicate the error. |
EFAULT |
addr or special are invalid. | ||
EINVAL |
The kernel has not been compiled with the QUOTA option. |
cmd is invalid.
ENOENT |
The file specified by special or addr does not exist. | ||
ENOTBLK |
special is not a block device. | ||
EPERM |
The call is privileged and the caller was not the super-user. | ||
ESRCH |
No disc quota is found for the indicated user. |
Quotas have not been turned on for this filesystem.
EUSERS |
The quota table is full. |
If cmd is Q_QUOTAON , quotactl() may set errno to:
EACCES |
The quota file pointed to by addr exists but is not a regular file. |
The quota file pointed to by addr exists but is not on the filesystem pointed to by special.
EBUSY |
Q_QUOTAON attempted while another Q_QUOTAON has already taken place. |
quota(1), getrlimit(2), quotacheck(8), quotaon(8)
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quotactl(2) | ![]() |