man2/quotactl.2

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  27 .TH QUOTACTL 2 2017-09-15 "Linux" "Linux Programmer's Manual"
  28 .SH NAME
  29 quotactl \- manipulate disk quotas
  30 .SH SYNOPSIS
  31 .nf
  32 .B #include <sys/quota.h>
  33 .B #include <xfs/xqm.h> /* for XFS quotas */
  34 .PP
  35 .BI "int quotactl(int " cmd ", const char *" special ", int " id \
  36 ", caddr_t " addr );
  37 .fi
  38 .SH DESCRIPTION
  39 .PP
  40 The quota system can be used to set per-user, per-group, and per-project limits
  41 on the amount of disk space used on a filesystem.
  42 For each user and/or group,
  43 a soft limit and a hard limit can be set for each filesystem.
  44 The hard limit can't be exceeded.
  45 The soft limit can be exceeded, but warnings will ensue.
  46 Moreover, the user can't exceed the soft limit for more than grace period
  47 duration (one week by default) at a time;
  48 after this, the soft limit counts as a hard limit.
  49 .PP
  50 The
  51 .BR quotactl ()
  52 call manipulates disk quotas.
  53 The
  54 .I cmd
  55 argument indicates a command to be applied to the user or
  56 group ID specified in
  57 .IR id .
  58 To initialize the
  59 .IR cmd
  60 argument, use the
  61 .IR "QCMD(subcmd, type)"
  62 macro.
  63 The
  64 .I type
  65 value is either
  66 .BR USRQUOTA ,
  67 for user quotas,
  68 .BR GRPQUOTA ,
  69 for group quotas, or (since Linux 4.1)
  70 .\" 847aac644e92e5624f2c153bab409bf713d5ff9a
  71 .BR PRJQUOTA ,
  72 for project quotas.
  73 The
  74 .I subcmd
  75 value is described below.
  76 .PP
  77 The
  78 .I special
  79 argument is a pointer to a null-terminated string containing the pathname
  80 of the (mounted) block special device for the filesystem being manipulated.
  81 .PP
  82 The
  83 .I addr
  84 argument is the address of an optional, command-specific, data structure
  85 that is copied in or out of the system.
  86 The interpretation of
  87 .I addr
  88 is given with each command below.
  89 .PP
  90 The
  91 .I subcmd
  92 value is one of the following:
  93 .TP 8
  94 .B Q_QUOTAON
  95 Turn on quotas for a filesystem.
  96 The
  97 .I id
  98 argument is the identification number of the quota format to be used.
  99 Currently, there are three supported quota formats:
 100 .RS
 101 .TP 13
 102 .BR QFMT_VFS_OLD
 103 The original quota format.
 104 .TP
 105 .BR QFMT_VFS_V0
 106 The standard VFS v0 quota format, which can handle 32-bit UIDs and GIDs
 107 and quota limits up to 2^42 bytes and 2^32 inodes.
 108 .TP
 109 .BR QFMT_VFS_V1
 110 A quota format that can handle 32-bit UIDs and GIDs
 111 and quota limits of 2^64 bytes and 2^64 inodes.
 112 .RE
 113 .IP
 114 The
 115 .IR addr
 116 argument points to the pathname of a file containing the quotas for
 117 the filesystem.
 118 The quota file must exist; it is normally created with the
 119 .BR quotacheck (8)
 120 program.
 121 This operation requires privilege
 122 .RB ( CAP_SYS_ADMIN ).
 123 .TP 8
 124 .B Q_QUOTAOFF
 125 Turn off quotas for a filesystem.
 126 The
 127 .I addr
 128 and
 129 .I id
 130 arguments are ignored.
 131 This operation requires privilege
 132 .RB ( CAP_SYS_ADMIN ).
 133 .TP
 134 .B Q_GETQUOTA
 135 Get disk quota limits and current usage for user or group
 136 .IR id .
 137 The
 138 .I addr
 139 argument is a pointer to a
 140 .I dqblk
 141 structure defined in
 142 .IR <sys/quota.h>
 143 as follows:
 144 .IP
 145 .in +4n
 146 .EX
 147 /* uint64_t is an unsigned 64\-bit integer;
 148    uint32_t is an unsigned 32\-bit integer */
 149
 150 struct dqblk {      /* Definition since Linux 2.4.22 */
 151     uint64_t dqb_bhardlimit;  /* Absolute limit on disk
 152                                  quota blocks alloc */
 153     uint64_t dqb_bsoftlimit;  /* Preferred limit on
 154                                  disk quota blocks */
 155     uint64_t dqb_curspace;    /* Current occupied space
 156                                  (in bytes) */
 157     uint64_t dqb_ihardlimit;  /* Maximum number of
 158                                  allocated inodes */
 159     uint64_t dqb_isoftlimit;  /* Preferred inode limit */
 160     uint64_t dqb_curinodes;   /* Current number of
 161                                  allocated inodes */
 162     uint64_t dqb_btime;       /* Time limit for excessive
 163                                  disk use */
 164     uint64_t dqb_itime;       /* Time limit for excessive
 165                                  files */
 166     uint32_t dqb_valid;       /* Bit mask of QIF_*
 167                                  constants */
 168 };
 169
 170 /* Flags in dqb_valid that indicate which fields in
 171    dqblk structure are valid. */
 172
 173 #define QIF_BLIMITS   1
 174 #define QIF_SPACE     2
 175 #define QIF_ILIMITS   4
 176 #define QIF_INODES    8
 177 #define QIF_BTIME     16
 178 #define QIF_ITIME     32
 179 #define QIF_LIMITS    (QIF_BLIMITS | QIF_ILIMITS)
 180 #define QIF_USAGE     (QIF_SPACE | QIF_INODES)
 181 #define QIF_TIMES     (QIF_BTIME | QIF_ITIME)
 182 #define QIF_ALL       (QIF_LIMITS | QIF_USAGE | QIF_TIMES)
 183 .EE
 184 .in
 185 .IP
 186 The
 187 .I dqb_valid
 188 field is a bit mask that is set to indicate the entries in the
 189 .I dqblk
 190 structure that are valid.
 191 Currently, the kernel fills in all entries of the
 192 .I dqblk
 193 structure and marks them as valid in the
 194 .I dqb_valid
 195 field.
 196 Unprivileged users may retrieve only their own quotas;
 197 a privileged user
 198 .RB ( CAP_SYS_ADMIN )
 199 can retrieve the quotas of any user.
 200 .TP
 201 .BR Q_GETNEXTQUOTA " (since Linux 4.6)"
 202 .\" commit 926132c0257a5a8d149a6a395cc3405e55420566
 203 This operation is the same as
 204 .BR Q_GETQUOTA ,
 205 but it returns quota information for the next ID greater than or equal to
 206 .IR id
 207 that has a quota set.
 208 .IP
 209 The
 210 .I addr
 211 argument is a pointer to a
 212 .I nextdqblk
 213 structure whose fields are as for the
 214 .IR dqblk ,
 215 except for the addition of a
 216 .I dqb_id
 217 field that is used to return the ID for which
 218 quota information is being returned:
 219 .IP
 220 .in +4n
 221 .EX
 222 struct nextdqblk {
 223     uint64_t dqb_bhardlimit;
 224     uint64_t dqb_bsoftlimit;
 225     uint64_t dqb_curspace;
 226     uint64_t dqb_ihardlimit;
 227     uint64_t dqb_isoftlimit;
 228     uint64_t dqb_curinodes;
 229     uint64_t dqb_btime;
 230     uint64_t dqb_itime;
 231     uint32_t dqb_valid;
 232     uint32_t dqb_id;
 233 };
 234 .EE
 235 .in
 236 .TP
 237 .B Q_SETQUOTA
 238 Set quota information for user or group
 239 .IR id ,
 240 using the information supplied in the
 241 .I dqblk
 242 structure pointed to by
 243 .IR addr .
 244 The
 245 .I dqb_valid
 246 field of the
 247 .I dqblk
 248 structure indicates which entries in the structure have been set by the caller.
 249 This operation supersedes the
 250 .B Q_SETQLIM
 251 and
 252 .B Q_SETUSE
 253 operations in the previous quota interfaces.
 254 This operation requires privilege
 255 .RB ( CAP_SYS_ADMIN ).
 256 .TP
 257 .BR Q_GETINFO " (since Linux 2.4.22)"
 258 Get information (like grace times) about quotafile.
 259 The
 260 .I addr
 261 argument should be a pointer to a
 262 .I dqinfo
 263 structure.
 264 This structure is defined in
 265 .IR <sys/quota.h>
 266 as follows:
 267 .IP
 268 .in +4n
 269 .EX
 270 /* uint64_t is an unsigned 64\-bit integer;
 271    uint32_t is an unsigned 32\-bit integer */
 272
 273 struct dqinfo {         /* Defined since kernel 2.4.22 */
 274     uint64_t dqi_bgrace;  /* Time before block soft limit
 275                              becomes hard limit */
 276     uint64_t dqi_igrace;  /* Time before inode soft limit
 277                              becomes hard limit */
 278     uint32_t dqi_flags;   /* Flags for quotafile
 279                              (DQF_*) */
 280     uint32_t dqi_valid;
 281 };
 282
 283 /* Bits for dqi_flags */
 284
 285 /* Quota format QFMT_VFS_OLD */
 286
 287 #define DQF_ROOT_SQUASH (1 << 0) /* Root squash enabled */
 288               /* Before Linux v4.0, this had been defined
 289                  privately as V1_DQF_RSQUASH */
 290
 291 /* Quota format QFMT_VFS_V0 / QFMT_VFS_V1 */
 292
 293 #define DQF_SYS_FILE    (1 << 16)   /* Quota stored in
 294                                        a system file */
 295
 296 /* Flags in dqi_valid that indicate which fields in
 297    dqinfo structure are valid. */
 298
 299 #define IIF_BGRACE  1
 300 #define IIF_IGRACE  2
 301 #define IIF_FLAGS   4
 302 #define IIF_ALL     (IIF_BGRACE | IIF_IGRACE | IIF_FLAGS)
 303 .EE
 304 .in
 305 .IP
 306 The
 307 .I dqi_valid
 308 field in the
 309 .I dqinfo
 310 structure indicates the entries in the structure that are valid.
 311 Currently, the kernel fills in all entries of the
 312 .I dqinfo
 313 structure and marks them all as valid in the
 314 .I dqi_valid
 315 field.
 316 The
 317 .I id
 318 argument is ignored.
 319 .TP
 320 .BR Q_SETINFO " (since Linux 2.4.22)"
 321 Set information about quotafile.
 322 The
 323 .I addr
 324 argument should be a pointer to a
 325 .I dqinfo
 326 structure.
 327 The
 328 .I dqi_valid
 329 field of the
 330 .I dqinfo
 331 structure indicates the entries in the structure
 332 that have been set by the caller.
 333 This operation supersedes the
 334 .B Q_SETGRACE
 335 and
 336 .B Q_SETFLAGS
 337 operations in the previous quota interfaces.
 338 The
 339 .I id
 340 argument is ignored.
 341 This operation requires privilege
 342 .RB ( CAP_SYS_ADMIN ).
 343 .TP
 344 .BR Q_GETFMT " (since Linux 2.4.22)"
 345 Get quota format used on the specified filesystem.
 346 The
 347 .I addr
 348 argument should be a pointer to a 4-byte buffer
 349 where the format number will be stored.
 350 .TP
 351 .B Q_SYNC
 352 Update the on-disk copy of quota usages for a filesystem.
 353 If
 354 .I special
 355 is NULL, then all filesystems with active quotas are sync'ed.
 356 The
 357 .I addr
 358 and
 359 .I id
 360 arguments are ignored.
 361 .TP
 362 .BR Q_GETSTATS " (supported up to Linux 2.4.21)"
 363 Get statistics and other generic information about the quota subsystem.
 364 The
 365 .I addr
 366 argument should be a pointer to a
 367 .I dqstats
 368 structure in which data should be stored.
 369 This structure is defined in
 370 .IR <sys/quota.h> .
 371 The
 372 .I special
 373 and
 374 .I id
 375 arguments are ignored.
 376 .IP
 377 This operation is obsolete and was removed in Linux 2.4.22.
 378 Files in
 379 .I /proc/sys/fs/quota/
 380 carry the information instead.
 381 .PP
 382 For XFS filesystems making use of the XFS Quota Manager (XQM),
 383 the above commands are bypassed and the following commands are used:
 384 .TP 8
 385 .B Q_XQUOTAON
 386 Turn on quotas for an XFS filesystem.
 387 XFS provides the ability to turn on/off quota limit enforcement
 388 with quota accounting.
 389 Therefore, XFS expects
 390 .I addr
 391 to be a pointer to an
 392 .I "unsigned int"
 393 that contains a combination of the following flags (defined in
 394 .IR <xfs/xqm.h> ):
 395 .IP
 396 .in +4n
 397 .EX
 398 #define XFS_QUOTA_UDQ_ACCT (1<<0) /* User quota
 399                                      accounting */
 400 #define XFS_QUOTA_UDQ_ENFD (1<<1) /* User quota limits
 401                                      enforcement */
 402 #define XFS_QUOTA_GDQ_ACCT (1<<2) /* Group quota
 403                                      accounting */
 404 #define XFS_QUOTA_GDQ_ENFD (1<<3) /* Group quota limits
 405                                      enforcement */
 406 #define XFS_QUOTA_PDQ_ACCT (1<<4) /* Project quota
 407                                      accounting */
 408 #define XFS_QUOTA_PDQ_ENFD (1<<5) /* Project quota limits
 409                                      enforcement */
 410 .EE
 411 .in
 412 .IP
 413 This operation requires privilege
 414 .RB ( CAP_SYS_ADMIN ).
 415 The
 416 .I id
 417 argument is ignored.
 418 .TP
 419 .B Q_XQUOTAOFF
 420 Turn off quotas for an XFS filesystem.
 421 As with
 422 .BR Q_QUOTAON ,
 423 XFS filesystems expect a pointer to an
 424 .I "unsigned int"
 425 that specifies whether quota accounting and/or limit enforcement need
 426 to be turned off (using the same flags as for
 427 .B Q_XQUOTAON
 428 subcommand).
 429 This operation requires privilege
 430 .RB ( CAP_SYS_ADMIN ).
 431 The
 432 .I id
 433 argument is ignored.
 434 .TP
 435 .B Q_XGETQUOTA
 436 Get disk quota limits and current usage for user
 437 .IR id .
 438 The
 439 .I addr
 440 argument is a pointer to an
 441 .I fs_disk_quota
 442 structure, which is defined in
 443 .I <xfs/xqm.h>
 444 as follows:
 445 .IP
 446 .in +4n
 447 .EX
 448 /* All the blk units are in BBs (Basic Blocks) of
 449    512 bytes. */
 450
 451 #define FS_DQUOT_VERSION  1  /* fs_disk_quota.d_version */
 452
 453 #define XFS_USER_QUOTA    (1<<0)  /* User quota type */
 454 #define XFS_PROJ_QUOTA    (1<<1)  /* Project quota type */
 455 #define XFS_GROUP_QUOTA   (1<<2)  /* Group quota type */
 456
 457 struct fs_disk_quota {
 458     int8_t   d_version;   /* Version of this structure */
 459     int8_t   d_flags;     /* XFS_{USER,PROJ,GROUP}_QUOTA */
 460     uint16_t d_fieldmask; /* Field specifier */
 461     uint32_t d_id;        /* User, project, or group ID */
 462     uint64_t d_blk_hardlimit; /* Absolute limit on
 463                                  disk blocks */
 464     uint64_t d_blk_softlimit; /* Preferred limit on
 465                                  disk blocks */
 466     uint64_t d_ino_hardlimit; /* Maximum # allocated
 467                                  inodes */
 468     uint64_t d_ino_softlimit; /* Preferred inode limit */
 469     uint64_t d_bcount;    /* # disk blocks owned by
 470                              the user */
 471     uint64_t d_icount;    /* # inodes owned by the user */
 472     int32_t  d_itimer;    /* Zero if within inode limits */
 473                           /* If not, we refuse service */
 474     int32_t  d_btimer;    /* Similar to above; for
 475                              disk blocks */
 476     uint16_t d_iwarns;    /* # warnings issued with
 477                              respect to # of inodes */
 478     uint16_t d_bwarns;    /* # warnings issued with
 479                              respect to disk blocks */
 480     int32_t  d_padding2;  /* Padding - for future use */
 481     uint64_t d_rtb_hardlimit; /* Absolute limit on realtime
 482                                  (RT) disk blocks */
 483     uint64_t d_rtb_softlimit; /* Preferred limit on RT
 484                                  disk blocks */
 485     uint64_t d_rtbcount;  /* # realtime blocks owned */
 486     int32_t  d_rtbtimer;  /* Similar to above; for RT
 487                              disk blocks */
 488     uint16_t d_rtbwarns;  /* # warnings issued with
 489                              respect to RT disk blocks */
 490     int16_t  d_padding3;  /* Padding - for future use */
 491     char     d_padding4[8];   /* Yet more padding */
 492 };
 493 .EE
 494 .in
 495 .IP
 496 Unprivileged users may retrieve only their own quotas;
 497 a privileged user
 498 .RB ( CAP_SYS_ADMIN )
 499 may retrieve the quotas of any user.
 500 .TP
 501 .BR Q_XGETNEXTQUOTA " (since Linux 4.6)"
 502 .\" commit 8b37524962b9c54423374717786198f5c0820a28
 503 This operation is the same as
 504 .BR Q_XGETQUOTA ,
 505 but it returns (in the
 506 .I fs_disk_quota
 507 structure pointed by
 508 .IR addr )
 509 quota information for the next ID greater than or equal to
 510 .IR id
 511 that has a quota set.
 512 Note that since
 513 .I fs_disk_quota
 514 already has
 515 .I q_id
 516 field, no separate structure type is needed (in contrast with
 517 .B Q_GETQUOTA
 518 and
 519 .B Q_GETNEXTQUOTA
 520 commands)
 521 .TP
 522 .B Q_XSETQLIM
 523 Set disk quota limits for user
 524 .IR id .
 525 The
 526 .I addr
 527 argument is a pointer to an
 528 .I fs_disk_quota
 529 structure.
 530 This operation requires privilege
 531 .RB ( CAP_SYS_ADMIN ).
 532 .TP
 533 .B Q_XGETQSTAT
 534 Returns XFS filesystem-specific quota information in the
 535 .I fs_quota_stat
 536 structure pointed by
 537 .IR addr .
 538 This is useful for finding out how much space is used to store quota
 539 information, and also to get the quota on/off status of a given local XFS
 540 filesystem.
 541 The
 542 .I fs_quota_stat
 543 structure itself is defined as follows:
 544 .IP
 545 .in +4n
 546 .EX
 547 #define FS_QSTAT_VERSION 1  /* fs_quota_stat.qs_version */
 548
 549 struct fs_qfilestat {
 550     uint64_t qfs_ino;       /* Inode number */
 551     uint64_t qfs_nblks;     /* Number of BBs
 552                                512-byte-blocks */
 553     uint32_t qfs_nextents;  /* Number of extents */
 554 };
 555
 556 struct fs_quota_stat {
 557     int8_t   qs_version; /* Version number for
 558                             future changes */
 559     uint16_t qs_flags; /* XFS_QUOTA_{U,P,G}DQ_{ACCT,ENFD} */
 560     int8_t   qs_pad;   /* Unused */
 561     struct fs_qfilestat qs_uquota;  /* User quota storage
 562                                        information */
 563     struct fs_qfilestat qs_gquota;  /* Group quota storage
 564                                        information */
 565     uint32_t qs_incoredqs;   /* Number of dquots in core */
 566     int32_t  qs_btimelimit;  /* Limit for blocks timer */
 567     int32_t  qs_itimelimit;  /* Limit for inodes timer */
 568     int32_t  qs_rtbtimelimit;/* Limit for RT
 569                                 blocks timer */
 570     uint16_t qs_bwarnlimit;  /* Limit for # of warnings */
 571     uint16_t qs_iwarnlimit;  /* Limit for # of warnings */
 572 };
 573 .EE
 574 .in
 575 .IP
 576 The
 577 .I id
 578 argument is ignored.
 579 .TP
 580 .B Q_XGETQSTATV
 581 Returns XFS filesystem-specific quota information in the
 582 .I fs_quota_statv
 583 pointed to by
 584 .IR addr .
 585 This version of the command uses a structure with proper versioning support,
 586 along with appropriate layout (all fields are naturally aligned) and
 587 padding to avoiding special compat handling;
 588 it also provides the ability to get statistics regarding
 589 the project quota file.
 590 The
 591 .I fs_quota_statv
 592 structure itself is defined as follows:
 593 .IP
 594 .in +4n
 595 .EX
 596 #define FS_QSTATV_VERSION1 1 /* fs_quota_statv.qs_version */
 597
 598 struct fs_qfilestatv {
 599     uint64_t qfs_ino;       /* Inode number */
 600     uint64_t qfs_nblks;     /* Number of BBs
 601                                512-byte-blocks */
 602     uint32_t qfs_nextents;  /* Number of extents */
 603     uint32_t qfs_pad;       /* Pad for 8-byte alignment */
 604 };
 605
 606 struct fs_quota_statv {
 607     int8_t   qs_version;    /* Version for future
 608                                changes */
 609     uint8_t  qs_pad1;       /* Pad for 16-bit alignment */
 610     uint16_t qs_flags;      /* XFS_QUOTA_.* flags */
 611     uint32_t qs_incoredqs;  /* Number of dquots incore */
 612     struct fs_qfilestatv qs_uquota;  /* User quota
 613                                         information */
 614     struct fs_qfilestatv qs_gquota;  /* Group quota
 615                                         information */
 616     struct fs_qfilestatv qs_pquota;  /* Project quota
 617                                         information */
 618     int32_t  qs_btimelimit;   /* Limit for blocks timer */
 619     int32_t  qs_itimelimit;   /* Limit for inodes timer */
 620     int32_t  qs_rtbtimelimit; /* Limit for RT blocks
 621                                  timer */
 622     uint16_t qs_bwarnlimit;   /* Limit for # of warnings */
 623     uint16_t qs_iwarnlimit;   /* Limit for # of warnings */
 624     uint64_t qs_pad2[8];      /* For future proofing */
 625 };
 626 .EE
 627 .in
 628 .IP
 629 The
 630 .I qs_version
 631 field of the structure should be filled with the version of the structure
 632 supported by the callee (for now, only
 633 .I FS_QSTAT_VERSION1
 634 is supported).
 635 The kernel will fill the structure in accordance with
 636 version provided.
 637 The
 638 .I id
 639 argument is ignored.
 640 .TP
 641 .B Q_XQUOTARM
 642 Free the disk space taken by disk quotas. The
 643 .I addr
 644 argument should be a pointer to an
 645 .I "unsigned int"
 646 value containing flags (the same as in
 647 .I d_flags
 648 field of
 649 .I fs_disk_quota
 650 structure) which identify what types of quota should be removed
 651 (note that the quota type passed in the
 652 .I cmd
 653 argument is ignored, but should remain valid in order to pass preliminary
 654 quotactl syscall handler checks).
 655 .IP
 656 Quotas must have already been turned off.
 657 The
 658 .I id
 659 argument is ignored.
 660 .TP
 661 .BR Q_XQUOTASYNC " (since Linux 2.6.15; no-op since Linux 3.4)"
 662 .\" Added in commit ee34807a65aa0c5911dc27682863afca780a003e
 663 This command was an XFS quota equivalent to
 664 .IR Q_SYNC ,
 665 but it is no-op since Linux 3.4,
 666 .\" 4b217ed9e30f94b6e8e5e262020ef0ceab6113af
 667 as
 668 .BR sync (1)
 669 writes quota information to disk now
 670 (in addition to the other filesystem metadata that it writes out).
 671 The
 672 .IR special ", " id " and " addr
 673 arguments are ignored.
 674 .SH RETURN VALUE
 675 .PP
 676 On success,
 677 .BR quotactl ()
 678 returns 0; on error \-1
 679 is returned, and
 680 .I errno
 681 is set to indicate the error.
 682 .SH ERRORS
 683 .TP
 684 .B EACCES
 685 .I cmd
 686 is
 687 .BR Q_QUOTAON ,
 688 and the quota file pointed to by
 689 .I addr
 690 exists, but is not a regular file or
 691 is not on the filesystem pointed to by
 692 .IR special .
 693 .TP
 694 .B EBUSY
 695 .I cmd
 696 is
 697 .BR Q_QUOTAON ,
 698 but another
 699 .B Q_QUOTAON
 700 had already been performed.
 701 .TP
 702 .B EFAULT
 703 .I addr
 704 or
 705 .I special
 706 is invalid.
 707 .TP
 708 .B EINVAL
 709 .I cmd
 710 or
 711 .I type
 712 is invalid.
 713 .TP
 714 .B EINVAL
 715 .I cmd
 716 is
 717 .BR Q_QUOTAON ,
 718 but the specified quota file is corrupted.
 719 .TP
 720 .B ENOENT
 721 The file specified by
 722 .I special
 723 or
 724 .I addr
 725 does not exist.
 726 .TP
 727 .B ENOSYS
 728 The kernel has not been compiled with the
 729 .B CONFIG_QUOTA
 730 option.
 731 .TP
 732 .B ENOTBLK
 733 .I special
 734 is not a block device.
 735 .TP
 736 .B EPERM
 737 The caller lacked the required privilege
 738 .RB ( CAP_SYS_ADMIN )
 739 for the specified operation.
 740 .TP
 741 .B ERANGE
 742 .I cmd
 743 is
 744 .BR Q_SETQUOTA ,
 745 but the specified limits are out of the range allowed by the quota format.
 746 .TP
 747 .B ESRCH
 748 No disk quota is found for the indicated user.
 749 Quotas have not been turned on for this filesystem.
 750 .TP
 751 .B ESRCH
 752 .I cmd
 753 is
 754 .BR Q_QUOTAON ,
 755 but the specified quota format was not found.
 756 .TP
 757 .B ESRCH
 758 .I cmd
 759 is
 760 .B Q_GETNEXTQUOTA
 761 or
 762 .BR Q_XGETNEXTQUOTA ,
 763 but there is no ID greater than or equal to
 764 .IR id
 765 that has an active quota.
 766 .SH NOTES
 767 Instead of
 768 .I <xfs/xqm.h>
 769 one can use
 770 .IR <linux/dqblk_xfs.h> ,
 771 taking into account that there are several naming discrepancies:
 772 .IP \(bu 3
 773 Quota enabling flags (of format
 774 .BR XFS_QUOTA_[UGP]DQ_{ACCT,ENFD} )
 775 are defined without a leading "X", as
 776 .BR FS_QUOTA_[UGP]DQ_{ACCT,ENFD} .
 777 .IP \(bu
 778 The same is true for
 779 .B XFS_{USER,GROUP,PROJ}_QUOTA
 780 quota type flags, which are defined as
 781 .BR FS_{USER,GROUP,PROJ}_QUOTA .
 782 .IP \(bu
 783 The
 784 .I dqblk_xfs.h
 785 header file defines its own
 786 .BR XQM_USRQUOTA ,
 787 .BR XQM_GRPQUOTA ,
 788 and
 789 .B XQM_PRJQUOTA
 790 constants for the available quota types, but their values are the same as for
 791 constants without the
 792 .B XQM_
 793 prefix.
 794 .SH SEE ALSO
 795 .BR quota (1),
 796 .BR getrlimit (2),
 797 .BR quotacheck (8),
 798 .BR quotaon (8)