sys_quotactl  [fs/quota.c]


Manipulates disk quota.

The quota system defines for each user and/or group a soft limit and a hard limit bounding the amount of disk space that can be used on a given file system. The hard limit cannot be crossed. The soft limit can be crossed, but warnings will ensue. Moreover, the user cannot be above the soft limit for more than one week (by default) at a time: after this week the soft limit counts as hard limit.

Arguments

eax 131
ebx Operation to perform. This argument is constructed as follows:

((cmd shl SUBCMDSHIFT) or (type and SUBCMDMASK))

Where cmd is one of the following:
Q_SYNC Sync disk copy of a filesystem's quota. *to be documented*
Q_QUOTAON Enable quota. The esi argument is the a pointer to a null-terminated string specifying the pathname of the file containing the quota for the filesystem.
Q_QUOTAOFF Disable quota.
esi is ignored.
Q_GETFMT *to be documented*
Q_GETINFO *to be documented*
Q_SETINFO *to be documented*
Q_GETQUOTA Get limits and current usage of disk space. The esi argument is a pointer to a if_dqblk structure which will receive the information:
struc if_dqblk
{
.dqb_bhardlimit rq 1
.dqb_bsoftlimit rq 1
.dqb_curspace   rq 1
.dqb_ihardlimit rq 1
.dqb_isoftlimit rq 1
.dqb_curinodes  rq 1
.dqb_btime      rq 1
.dqb_itime      rq 1
.dqb_valid      rq 1
}
Q_SETQUOTA Set limits and current usage. The esi argument is a pointer to a properly initialized if_dqblk structure. See above.
And type is one of the following:
USRQUOTA User quota.
GRPQUOTA Group quota.
ecx A pointer to a null-terminated string specifying the block special device these quota apply to. It must be mounted.
edx User or group ID these quota apply to.
esi This argument depends on the cmd used See above.

Return values

If the system call succeeds the return value is 0.
If the system call fails the return value is one of the following errno values:

-EACCES The quota file is not an ordinary file.
-EBUSY Q_QUOTAON was asked, but quotas were enabled already.
-EFAULT Bad esi value.
-EINVAL type is not a known quota type. Or, pathname pointed by ecx could not be found.
-EIO Cannot read or write the quota file.
-EMFILE Too many open files: cannot open quota file.
-ENODEV Pathname pointed by ecx cannot be found in the mount table.
-ENOPKG The kernel was compiled without quota support.
-ENOTBLK Pathname pointed by ecx is not a block special device.
-EPERM The process was not root (for the file system), and Q_GETQUOTA was asked for another id than that of the process itself, or anything other than Q_SYNC was asked.
-ESRCH Q_GETQUOTA or Q_SETQUOTA was asked for a file system that didn't have quota enabled.

Remarks

n/a

Compatibility

n/a