1QUOTACTL(2) System Calls Manual QUOTACTL(2)
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6 quotactl - manipulate disk quotas
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9 #include <sys/quota.h>
10 #include <sys/types.h>
11 #include <xfs/xqm.h>
12 long quotactl(int cmd, char ∗special, int id, caddr_t addr)
14
16 The quotactl() call manipulates disk quotas. cmd indicates a command
17 to be applied to UID id or GID id. To set the type of quota use the
18 QCMD(cmd, type) macro. special is a pointer to a null-terminated
19 string containing the path name of the block special device for the
20 filesystem being manipulated. addr is the address of an optional, com‐
21 mand specific, data structure which is copied in or out of the system.
22 The interpretation of addr is given with each command below.
23 Q_QUOTAON Turn on quotas for a filesystem. id is the identifica‐
25 tion number of the quota format to be used. Format num‐
26 bers are defined in the header file of appropriate for‐
27 mat. Currently there are two supported quota formats
28 whose numbers are defined by constants QFMT_VFS_OLD
29 (original quota format) and QFMT_VFS_V0 (new VFS v0
30 quota format). addr points to the path name of file
31 containing the quotas for the filesystem. The quota
32 file must exist; it is normally created with the quo‐
33 tacheck(8) program. This call is restricted to the
34 super-user.
35 Q_QUOTAOFF Turn off quotas for a filesystem. addr and id are
37 ignored. This call is restricted to the super-user.
38 Q_GETQUOTA Get disk quota limits and current usage for user or
40 group id. addr is a pointer to an dqblk structure
41 (defined in <sys/quota.h>). The field dqb_valid defines
42 the entries in the structure which are set correctly. On
43 Q_GETQUOTA call all entries are valid. Only the super-
44 user may get the quotas of a user other than himself.
45 Q_SETQUOTA Set current quota information for user or group id.
47 addr is a pointer to an dqblk structure (defined in
48 <sys/quota.h>). The field dqb_valid defines which
49 entries in the quota structure are valid and should be
50 set. The constants for dqb_valid field are defined in
51 the <sys/quota.h> header file. This call obsoletes calls
52 Q_SETQLIM and Q_SETUSE in the previous quota interfaces.
53 This call is restricted to the super-user.
54 Q_GETINFO Get information (like grace times) about quotafile.
56 addr should be a pointer to an dqinfo structure (defined
57 in <sys/quota.h>). The dqi_valid field in the structure
58 defines entries in it which are valid. On Q_GETINFO call
59 all entries are valid. Parameter id is ignored.
60 Q_SETINFO Set information about quotafile. addr should be a
62 pointer to dqinfo structure (defined in <sys/quota.h>).
63 The field dqi_valid defines which entries in the quota
64 info structure are valid and should be set. The con‐
65 stants for dqi_valid field are defined in the
66 <sys/quota.h> header file. This call obsoletes calls
67 Q_SETGRACE and Q_SETFLAGS in the previous quota inter‐
68 faces. Parameter id is ignored. This operation is
69 restricted to super-user.
70 Q_GETFMT Get quota format used on the specified filesystem. addr
72 should be a pointer to a memory (4 bytes) where the for‐
73 mat number will be stored.
74 Q_SYNC Update the on-disk copy of quota usages for a filesys‐
76 tem. If special is null then all filesystems with
77 active quotas are sync'ed. addr and id are ignored.
78 Q_GETSTATS Get statistics and other generic information about quota
80 subsystem. addr should be a pointer to dqstats struc‐
81 ture (defined in <sys/quota.h>) in which data should be
82 stored. special and id are ignored.
83 For XFS filesystems making use of the XFS Quota Manager (XQM), the
85 above commands are bypassed and the following commands are used:
86 Q_XQUOTAON Turn on quotas for an XFS filesystem. XFS provides the
88 ability to turn on/off quota limit enforcement with
89 quota accounting. Therefore, XFS expects the addr to be
90 a pointer to an unsigned int that contains either the
91 flags XFS_QUOTA_UDQ_ACCT and/or XFS_QUOTA_UDQ_ENFD (for
92 user quota), or XFS_QUOTA_GDQ_ACCT and/or
93 XFS_QUOTA_GDQ_ENFD (for group quota), as defined in
94 <xfs/xqm.h>. This call is restricted to the superuser.
95 Q_XQUOTAOFF Turn off quotas for an XFS filesystem. As in Q_QUOTAON,
97 XFS filesystems expect a pointer to an unsigned int that
98 specifies whether quota accounting and/or limit enforce‐
99 ment need to be turned off. This call is restricted to
100 the superuser.
101 Q_XGETQUOTA Get disk quota limits and current usage for user id.
103 addr is a pointer to a fs_disk_quota structure (defined
104 in <xfs/xqm.h>). Only the superuser may get the quotas
105 of a user other than himself.
106 Q_XSETQLIM Set disk quota limits for user id. addr is a pointer to
108 a fs_disk_quota structure (defined in <xfs/xqm.h>).
109 This call is restricted to the superuser.
110 Q_XGETQSTAT Returns a fs_quota_stat structure containing XFS
112 filesystem specific quota information. This is useful
113 in finding out how much space is spent to store quota
114 information, and also to get quotaon/off status of a
115 given local XFS filesystem.
116 Q_XQUOTARM Free the disk space taken by disk quotas. Quotas must
118 have already been turned off.
119 There is no command equivalent to Q_SYNC for XFS since sync(1) writes
121 quota information to disk (in addition to the other filesystem metadata
122 it writes out).
123
125 quotactl() returns:
126 0 on success.
128 -1 on failure and sets errno to indicate the error.
130
132 EFAULT addr or special are invalid.
133 ENOSYS The kernel has not been compiled with the QUOTA option.
135 EINVAL
137 cmd or type is invalid.
139 ENOENT The file specified by special or addr does not exist.
141 ENOTBLK special is not a block device.
143 EPERM The call is privileged and the caller was not the super-
145 user.
146 ESRCH No disc quota is found for the indicated user.
148 Quotas have not been turned on for this filesystem.
150 If cmd is Q_QUOTAON, quotactl() may set errno to:
152 EACCES The quota file pointed to by addr exists but is not a
154 regular file.
155 The quota file pointed to by addr exists but is not on
157 the filesystem pointed to by special.
158 EINVAL The quota file is corrupted.
160 ESRCH Specified quota format was not found.
162 EBUSY Q_QUOTAON attempted while another Q_QUOTAON has already
164 taken place.
165
167 quota(1), getrlimit(2), quotacheck(8), quotaon(8)
168 QUOTACTL(2)