1 // SPDX-License-Identifier: GPL-2.0
3 * Quota code necessary even when VFS quota support is not compiled
4 * into the kernel. The interesting stuff is over in dquot.c, here
5 * we have symbols for initial quotactl(2) handling, the sysctl(2)
6 * variables, etc - things needed even when quota support disabled.
10 #include <linux/namei.h>
11 #include <linux/slab.h>
12 #include <asm/current.h>
13 #include <linux/uaccess.h>
14 #include <linux/kernel.h>
15 #include <linux/security.h>
16 #include <linux/syscalls.h>
17 #include <linux/capability.h>
18 #include <linux/quotaops.h>
19 #include <linux/types.h>
20 #include <linux/writeback.h>
22 static int check_quotactl_permission(struct super_block *sb, int type, int cmd,
26 /* these commands do not require any special privilegues */
34 /* allow to query information for dquots we "own" */
37 if ((type == USRQUOTA && uid_eq(current_euid(), make_kuid(current_user_ns(), id))) ||
38 (type == GRPQUOTA && in_egroup_p(make_kgid(current_user_ns(), id))))
42 if (!capable(CAP_SYS_ADMIN))
46 return security_quotactl(cmd, type, id, sb);
49 static void quota_sync_one(struct super_block *sb, void *arg)
51 int type = *(int *)arg;
53 if (sb->s_qcop && sb->s_qcop->quota_sync &&
54 (sb->s_quota_types & (1 << type)))
55 sb->s_qcop->quota_sync(sb, type);
58 static int quota_sync_all(int type)
62 if (type >= MAXQUOTAS)
64 ret = security_quotactl(Q_SYNC, type, 0, NULL);
66 iterate_supers(quota_sync_one, &type);
70 unsigned int qtype_enforce_flag(int type)
74 return FS_QUOTA_UDQ_ENFD;
76 return FS_QUOTA_GDQ_ENFD;
78 return FS_QUOTA_PDQ_ENFD;
83 static int quota_quotaon(struct super_block *sb, int type, qid_t id,
84 const struct path *path)
86 if (!sb->s_qcop->quota_on && !sb->s_qcop->quota_enable)
88 if (sb->s_qcop->quota_enable)
89 return sb->s_qcop->quota_enable(sb, qtype_enforce_flag(type));
92 return sb->s_qcop->quota_on(sb, type, id, path);
95 static int quota_quotaoff(struct super_block *sb, int type)
97 if (!sb->s_qcop->quota_off && !sb->s_qcop->quota_disable)
99 if (sb->s_qcop->quota_disable)
100 return sb->s_qcop->quota_disable(sb, qtype_enforce_flag(type));
101 return sb->s_qcop->quota_off(sb, type);
104 static int quota_getfmt(struct super_block *sb, int type, void __user *addr)
108 if (!sb_has_quota_active(sb, type))
110 fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id;
111 if (copy_to_user(addr, &fmt, sizeof(fmt)))
116 static int quota_getinfo(struct super_block *sb, int type, void __user *addr)
118 struct qc_state state;
119 struct qc_type_state *tstate;
120 struct if_dqinfo uinfo;
123 /* This checks whether qc_state has enough entries... */
124 BUILD_BUG_ON(MAXQUOTAS > XQM_MAXQUOTAS);
125 if (!sb->s_qcop->get_state)
127 ret = sb->s_qcop->get_state(sb, &state);
130 tstate = state.s_state + type;
131 if (!(tstate->flags & QCI_ACCT_ENABLED))
133 memset(&uinfo, 0, sizeof(uinfo));
134 uinfo.dqi_bgrace = tstate->spc_timelimit;
135 uinfo.dqi_igrace = tstate->ino_timelimit;
136 if (tstate->flags & QCI_SYSFILE)
137 uinfo.dqi_flags |= DQF_SYS_FILE;
138 if (tstate->flags & QCI_ROOT_SQUASH)
139 uinfo.dqi_flags |= DQF_ROOT_SQUASH;
140 uinfo.dqi_valid = IIF_ALL;
141 if (copy_to_user(addr, &uinfo, sizeof(uinfo)))
146 static int quota_setinfo(struct super_block *sb, int type, void __user *addr)
148 struct if_dqinfo info;
149 struct qc_info qinfo;
151 if (copy_from_user(&info, addr, sizeof(info)))
153 if (!sb->s_qcop->set_info)
155 if (info.dqi_valid & ~(IIF_FLAGS | IIF_BGRACE | IIF_IGRACE))
157 memset(&qinfo, 0, sizeof(qinfo));
158 if (info.dqi_valid & IIF_FLAGS) {
159 if (info.dqi_flags & ~DQF_SETINFO_MASK)
161 if (info.dqi_flags & DQF_ROOT_SQUASH)
162 qinfo.i_flags |= QCI_ROOT_SQUASH;
163 qinfo.i_fieldmask |= QC_FLAGS;
165 if (info.dqi_valid & IIF_BGRACE) {
166 qinfo.i_spc_timelimit = info.dqi_bgrace;
167 qinfo.i_fieldmask |= QC_SPC_TIMER;
169 if (info.dqi_valid & IIF_IGRACE) {
170 qinfo.i_ino_timelimit = info.dqi_igrace;
171 qinfo.i_fieldmask |= QC_INO_TIMER;
173 return sb->s_qcop->set_info(sb, type, &qinfo);
176 static inline qsize_t qbtos(qsize_t blocks)
178 return blocks << QIF_DQBLKSIZE_BITS;
181 static inline qsize_t stoqb(qsize_t space)
183 return (space + QIF_DQBLKSIZE - 1) >> QIF_DQBLKSIZE_BITS;
186 static void copy_to_if_dqblk(struct if_dqblk *dst, struct qc_dqblk *src)
188 memset(dst, 0, sizeof(*dst));
189 dst->dqb_bhardlimit = stoqb(src->d_spc_hardlimit);
190 dst->dqb_bsoftlimit = stoqb(src->d_spc_softlimit);
191 dst->dqb_curspace = src->d_space;
192 dst->dqb_ihardlimit = src->d_ino_hardlimit;
193 dst->dqb_isoftlimit = src->d_ino_softlimit;
194 dst->dqb_curinodes = src->d_ino_count;
195 dst->dqb_btime = src->d_spc_timer;
196 dst->dqb_itime = src->d_ino_timer;
197 dst->dqb_valid = QIF_ALL;
200 static int quota_getquota(struct super_block *sb, int type, qid_t id,
208 if (!sb->s_qcop->get_dqblk)
210 qid = make_kqid(current_user_ns(), type, id);
211 if (!qid_has_mapping(sb->s_user_ns, qid))
213 ret = sb->s_qcop->get_dqblk(sb, qid, &fdq);
216 copy_to_if_dqblk(&idq, &fdq);
217 if (copy_to_user(addr, &idq, sizeof(idq)))
223 * Return quota for next active quota >= this id, if any exists,
224 * otherwise return -ENOENT via ->get_nextdqblk
226 static int quota_getnextquota(struct super_block *sb, int type, qid_t id,
231 struct if_nextdqblk idq;
234 if (!sb->s_qcop->get_nextdqblk)
236 qid = make_kqid(current_user_ns(), type, id);
237 if (!qid_has_mapping(sb->s_user_ns, qid))
239 ret = sb->s_qcop->get_nextdqblk(sb, &qid, &fdq);
242 /* struct if_nextdqblk is a superset of struct if_dqblk */
243 copy_to_if_dqblk((struct if_dqblk *)&idq, &fdq);
244 idq.dqb_id = from_kqid(current_user_ns(), qid);
245 if (copy_to_user(addr, &idq, sizeof(idq)))
250 static void copy_from_if_dqblk(struct qc_dqblk *dst, struct if_dqblk *src)
252 dst->d_spc_hardlimit = qbtos(src->dqb_bhardlimit);
253 dst->d_spc_softlimit = qbtos(src->dqb_bsoftlimit);
254 dst->d_space = src->dqb_curspace;
255 dst->d_ino_hardlimit = src->dqb_ihardlimit;
256 dst->d_ino_softlimit = src->dqb_isoftlimit;
257 dst->d_ino_count = src->dqb_curinodes;
258 dst->d_spc_timer = src->dqb_btime;
259 dst->d_ino_timer = src->dqb_itime;
261 dst->d_fieldmask = 0;
262 if (src->dqb_valid & QIF_BLIMITS)
263 dst->d_fieldmask |= QC_SPC_SOFT | QC_SPC_HARD;
264 if (src->dqb_valid & QIF_SPACE)
265 dst->d_fieldmask |= QC_SPACE;
266 if (src->dqb_valid & QIF_ILIMITS)
267 dst->d_fieldmask |= QC_INO_SOFT | QC_INO_HARD;
268 if (src->dqb_valid & QIF_INODES)
269 dst->d_fieldmask |= QC_INO_COUNT;
270 if (src->dqb_valid & QIF_BTIME)
271 dst->d_fieldmask |= QC_SPC_TIMER;
272 if (src->dqb_valid & QIF_ITIME)
273 dst->d_fieldmask |= QC_INO_TIMER;
276 static int quota_setquota(struct super_block *sb, int type, qid_t id,
283 if (copy_from_user(&idq, addr, sizeof(idq)))
285 if (!sb->s_qcop->set_dqblk)
287 qid = make_kqid(current_user_ns(), type, id);
288 if (!qid_has_mapping(sb->s_user_ns, qid))
290 copy_from_if_dqblk(&fdq, &idq);
291 return sb->s_qcop->set_dqblk(sb, qid, &fdq);
294 static int quota_enable(struct super_block *sb, void __user *addr)
298 if (copy_from_user(&flags, addr, sizeof(flags)))
300 if (!sb->s_qcop->quota_enable)
302 return sb->s_qcop->quota_enable(sb, flags);
305 static int quota_disable(struct super_block *sb, void __user *addr)
309 if (copy_from_user(&flags, addr, sizeof(flags)))
311 if (!sb->s_qcop->quota_disable)
313 return sb->s_qcop->quota_disable(sb, flags);
316 static int quota_state_to_flags(struct qc_state *state)
320 if (state->s_state[USRQUOTA].flags & QCI_ACCT_ENABLED)
321 flags |= FS_QUOTA_UDQ_ACCT;
322 if (state->s_state[USRQUOTA].flags & QCI_LIMITS_ENFORCED)
323 flags |= FS_QUOTA_UDQ_ENFD;
324 if (state->s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED)
325 flags |= FS_QUOTA_GDQ_ACCT;
326 if (state->s_state[GRPQUOTA].flags & QCI_LIMITS_ENFORCED)
327 flags |= FS_QUOTA_GDQ_ENFD;
328 if (state->s_state[PRJQUOTA].flags & QCI_ACCT_ENABLED)
329 flags |= FS_QUOTA_PDQ_ACCT;
330 if (state->s_state[PRJQUOTA].flags & QCI_LIMITS_ENFORCED)
331 flags |= FS_QUOTA_PDQ_ENFD;
335 static int quota_getstate(struct super_block *sb, struct fs_quota_stat *fqs)
338 struct qc_state state;
341 memset(&state, 0, sizeof (struct qc_state));
342 ret = sb->s_qcop->get_state(sb, &state);
346 memset(fqs, 0, sizeof(*fqs));
347 fqs->qs_version = FS_QSTAT_VERSION;
348 fqs->qs_flags = quota_state_to_flags(&state);
349 /* No quota enabled? */
352 fqs->qs_incoredqs = state.s_incoredqs;
354 * GETXSTATE quotactl has space for just one set of time limits so
355 * report them for the first enabled quota type
357 for (type = 0; type < XQM_MAXQUOTAS; type++)
358 if (state.s_state[type].flags & QCI_ACCT_ENABLED)
360 BUG_ON(type == XQM_MAXQUOTAS);
361 fqs->qs_btimelimit = state.s_state[type].spc_timelimit;
362 fqs->qs_itimelimit = state.s_state[type].ino_timelimit;
363 fqs->qs_rtbtimelimit = state.s_state[type].rt_spc_timelimit;
364 fqs->qs_bwarnlimit = state.s_state[type].spc_warnlimit;
365 fqs->qs_iwarnlimit = state.s_state[type].ino_warnlimit;
367 /* Inodes may be allocated even if inactive; copy out if present */
368 if (state.s_state[USRQUOTA].ino) {
369 fqs->qs_uquota.qfs_ino = state.s_state[USRQUOTA].ino;
370 fqs->qs_uquota.qfs_nblks = state.s_state[USRQUOTA].blocks;
371 fqs->qs_uquota.qfs_nextents = state.s_state[USRQUOTA].nextents;
373 if (state.s_state[GRPQUOTA].ino) {
374 fqs->qs_gquota.qfs_ino = state.s_state[GRPQUOTA].ino;
375 fqs->qs_gquota.qfs_nblks = state.s_state[GRPQUOTA].blocks;
376 fqs->qs_gquota.qfs_nextents = state.s_state[GRPQUOTA].nextents;
378 if (state.s_state[PRJQUOTA].ino) {
380 * Q_XGETQSTAT doesn't have room for both group and project
381 * quotas. So, allow the project quota values to be copied out
382 * only if there is no group quota information available.
384 if (!(state.s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED)) {
385 fqs->qs_gquota.qfs_ino = state.s_state[PRJQUOTA].ino;
386 fqs->qs_gquota.qfs_nblks =
387 state.s_state[PRJQUOTA].blocks;
388 fqs->qs_gquota.qfs_nextents =
389 state.s_state[PRJQUOTA].nextents;
395 static int quota_getxstate(struct super_block *sb, void __user *addr)
397 struct fs_quota_stat fqs;
400 if (!sb->s_qcop->get_state)
402 ret = quota_getstate(sb, &fqs);
403 if (!ret && copy_to_user(addr, &fqs, sizeof(fqs)))
408 static int quota_getstatev(struct super_block *sb, struct fs_quota_statv *fqs)
411 struct qc_state state;
414 memset(&state, 0, sizeof (struct qc_state));
415 ret = sb->s_qcop->get_state(sb, &state);
419 memset(fqs, 0, sizeof(*fqs));
420 fqs->qs_version = FS_QSTAT_VERSION;
421 fqs->qs_flags = quota_state_to_flags(&state);
422 /* No quota enabled? */
425 fqs->qs_incoredqs = state.s_incoredqs;
427 * GETXSTATV quotactl has space for just one set of time limits so
428 * report them for the first enabled quota type
430 for (type = 0; type < XQM_MAXQUOTAS; type++)
431 if (state.s_state[type].flags & QCI_ACCT_ENABLED)
433 BUG_ON(type == XQM_MAXQUOTAS);
434 fqs->qs_btimelimit = state.s_state[type].spc_timelimit;
435 fqs->qs_itimelimit = state.s_state[type].ino_timelimit;
436 fqs->qs_rtbtimelimit = state.s_state[type].rt_spc_timelimit;
437 fqs->qs_bwarnlimit = state.s_state[type].spc_warnlimit;
438 fqs->qs_iwarnlimit = state.s_state[type].ino_warnlimit;
440 /* Inodes may be allocated even if inactive; copy out if present */
441 if (state.s_state[USRQUOTA].ino) {
442 fqs->qs_uquota.qfs_ino = state.s_state[USRQUOTA].ino;
443 fqs->qs_uquota.qfs_nblks = state.s_state[USRQUOTA].blocks;
444 fqs->qs_uquota.qfs_nextents = state.s_state[USRQUOTA].nextents;
446 if (state.s_state[GRPQUOTA].ino) {
447 fqs->qs_gquota.qfs_ino = state.s_state[GRPQUOTA].ino;
448 fqs->qs_gquota.qfs_nblks = state.s_state[GRPQUOTA].blocks;
449 fqs->qs_gquota.qfs_nextents = state.s_state[GRPQUOTA].nextents;
451 if (state.s_state[PRJQUOTA].ino) {
452 fqs->qs_pquota.qfs_ino = state.s_state[PRJQUOTA].ino;
453 fqs->qs_pquota.qfs_nblks = state.s_state[PRJQUOTA].blocks;
454 fqs->qs_pquota.qfs_nextents = state.s_state[PRJQUOTA].nextents;
459 static int quota_getxstatev(struct super_block *sb, void __user *addr)
461 struct fs_quota_statv fqs;
464 if (!sb->s_qcop->get_state)
467 memset(&fqs, 0, sizeof(fqs));
468 if (copy_from_user(&fqs, addr, 1)) /* Just read qs_version */
471 /* If this kernel doesn't support user specified version, fail */
472 switch (fqs.qs_version) {
473 case FS_QSTATV_VERSION1:
478 ret = quota_getstatev(sb, &fqs);
479 if (!ret && copy_to_user(addr, &fqs, sizeof(fqs)))
485 * XFS defines BBTOB and BTOBB macros inside fs/xfs/ and we cannot move them
486 * out of there as xfsprogs rely on definitions being in that header file. So
487 * just define same functions here for quota purposes.
489 #define XFS_BB_SHIFT 9
491 static inline u64 quota_bbtob(u64 blocks)
493 return blocks << XFS_BB_SHIFT;
496 static inline u64 quota_btobb(u64 bytes)
498 return (bytes + (1 << XFS_BB_SHIFT) - 1) >> XFS_BB_SHIFT;
501 static void copy_from_xfs_dqblk(struct qc_dqblk *dst, struct fs_disk_quota *src)
503 dst->d_spc_hardlimit = quota_bbtob(src->d_blk_hardlimit);
504 dst->d_spc_softlimit = quota_bbtob(src->d_blk_softlimit);
505 dst->d_ino_hardlimit = src->d_ino_hardlimit;
506 dst->d_ino_softlimit = src->d_ino_softlimit;
507 dst->d_space = quota_bbtob(src->d_bcount);
508 dst->d_ino_count = src->d_icount;
509 dst->d_ino_timer = src->d_itimer;
510 dst->d_spc_timer = src->d_btimer;
511 dst->d_ino_warns = src->d_iwarns;
512 dst->d_spc_warns = src->d_bwarns;
513 dst->d_rt_spc_hardlimit = quota_bbtob(src->d_rtb_hardlimit);
514 dst->d_rt_spc_softlimit = quota_bbtob(src->d_rtb_softlimit);
515 dst->d_rt_space = quota_bbtob(src->d_rtbcount);
516 dst->d_rt_spc_timer = src->d_rtbtimer;
517 dst->d_rt_spc_warns = src->d_rtbwarns;
518 dst->d_fieldmask = 0;
519 if (src->d_fieldmask & FS_DQ_ISOFT)
520 dst->d_fieldmask |= QC_INO_SOFT;
521 if (src->d_fieldmask & FS_DQ_IHARD)
522 dst->d_fieldmask |= QC_INO_HARD;
523 if (src->d_fieldmask & FS_DQ_BSOFT)
524 dst->d_fieldmask |= QC_SPC_SOFT;
525 if (src->d_fieldmask & FS_DQ_BHARD)
526 dst->d_fieldmask |= QC_SPC_HARD;
527 if (src->d_fieldmask & FS_DQ_RTBSOFT)
528 dst->d_fieldmask |= QC_RT_SPC_SOFT;
529 if (src->d_fieldmask & FS_DQ_RTBHARD)
530 dst->d_fieldmask |= QC_RT_SPC_HARD;
531 if (src->d_fieldmask & FS_DQ_BTIMER)
532 dst->d_fieldmask |= QC_SPC_TIMER;
533 if (src->d_fieldmask & FS_DQ_ITIMER)
534 dst->d_fieldmask |= QC_INO_TIMER;
535 if (src->d_fieldmask & FS_DQ_RTBTIMER)
536 dst->d_fieldmask |= QC_RT_SPC_TIMER;
537 if (src->d_fieldmask & FS_DQ_BWARNS)
538 dst->d_fieldmask |= QC_SPC_WARNS;
539 if (src->d_fieldmask & FS_DQ_IWARNS)
540 dst->d_fieldmask |= QC_INO_WARNS;
541 if (src->d_fieldmask & FS_DQ_RTBWARNS)
542 dst->d_fieldmask |= QC_RT_SPC_WARNS;
543 if (src->d_fieldmask & FS_DQ_BCOUNT)
544 dst->d_fieldmask |= QC_SPACE;
545 if (src->d_fieldmask & FS_DQ_ICOUNT)
546 dst->d_fieldmask |= QC_INO_COUNT;
547 if (src->d_fieldmask & FS_DQ_RTBCOUNT)
548 dst->d_fieldmask |= QC_RT_SPACE;
551 static void copy_qcinfo_from_xfs_dqblk(struct qc_info *dst,
552 struct fs_disk_quota *src)
554 memset(dst, 0, sizeof(*dst));
555 dst->i_spc_timelimit = src->d_btimer;
556 dst->i_ino_timelimit = src->d_itimer;
557 dst->i_rt_spc_timelimit = src->d_rtbtimer;
558 dst->i_ino_warnlimit = src->d_iwarns;
559 dst->i_spc_warnlimit = src->d_bwarns;
560 dst->i_rt_spc_warnlimit = src->d_rtbwarns;
561 if (src->d_fieldmask & FS_DQ_BWARNS)
562 dst->i_fieldmask |= QC_SPC_WARNS;
563 if (src->d_fieldmask & FS_DQ_IWARNS)
564 dst->i_fieldmask |= QC_INO_WARNS;
565 if (src->d_fieldmask & FS_DQ_RTBWARNS)
566 dst->i_fieldmask |= QC_RT_SPC_WARNS;
567 if (src->d_fieldmask & FS_DQ_BTIMER)
568 dst->i_fieldmask |= QC_SPC_TIMER;
569 if (src->d_fieldmask & FS_DQ_ITIMER)
570 dst->i_fieldmask |= QC_INO_TIMER;
571 if (src->d_fieldmask & FS_DQ_RTBTIMER)
572 dst->i_fieldmask |= QC_RT_SPC_TIMER;
575 static int quota_setxquota(struct super_block *sb, int type, qid_t id,
578 struct fs_disk_quota fdq;
582 if (copy_from_user(&fdq, addr, sizeof(fdq)))
584 if (!sb->s_qcop->set_dqblk)
586 qid = make_kqid(current_user_ns(), type, id);
587 if (!qid_has_mapping(sb->s_user_ns, qid))
589 /* Are we actually setting timer / warning limits for all users? */
590 if (from_kqid(sb->s_user_ns, qid) == 0 &&
591 fdq.d_fieldmask & (FS_DQ_WARNS_MASK | FS_DQ_TIMER_MASK)) {
592 struct qc_info qinfo;
595 if (!sb->s_qcop->set_info)
597 copy_qcinfo_from_xfs_dqblk(&qinfo, &fdq);
598 ret = sb->s_qcop->set_info(sb, type, &qinfo);
601 /* These are already done */
602 fdq.d_fieldmask &= ~(FS_DQ_WARNS_MASK | FS_DQ_TIMER_MASK);
604 copy_from_xfs_dqblk(&qdq, &fdq);
605 return sb->s_qcop->set_dqblk(sb, qid, &qdq);
608 static void copy_to_xfs_dqblk(struct fs_disk_quota *dst, struct qc_dqblk *src,
611 memset(dst, 0, sizeof(*dst));
612 dst->d_version = FS_DQUOT_VERSION;
614 if (type == USRQUOTA)
615 dst->d_flags = FS_USER_QUOTA;
616 else if (type == PRJQUOTA)
617 dst->d_flags = FS_PROJ_QUOTA;
619 dst->d_flags = FS_GROUP_QUOTA;
620 dst->d_blk_hardlimit = quota_btobb(src->d_spc_hardlimit);
621 dst->d_blk_softlimit = quota_btobb(src->d_spc_softlimit);
622 dst->d_ino_hardlimit = src->d_ino_hardlimit;
623 dst->d_ino_softlimit = src->d_ino_softlimit;
624 dst->d_bcount = quota_btobb(src->d_space);
625 dst->d_icount = src->d_ino_count;
626 dst->d_itimer = src->d_ino_timer;
627 dst->d_btimer = src->d_spc_timer;
628 dst->d_iwarns = src->d_ino_warns;
629 dst->d_bwarns = src->d_spc_warns;
630 dst->d_rtb_hardlimit = quota_btobb(src->d_rt_spc_hardlimit);
631 dst->d_rtb_softlimit = quota_btobb(src->d_rt_spc_softlimit);
632 dst->d_rtbcount = quota_btobb(src->d_rt_space);
633 dst->d_rtbtimer = src->d_rt_spc_timer;
634 dst->d_rtbwarns = src->d_rt_spc_warns;
637 static int quota_getxquota(struct super_block *sb, int type, qid_t id,
640 struct fs_disk_quota fdq;
645 if (!sb->s_qcop->get_dqblk)
647 qid = make_kqid(current_user_ns(), type, id);
648 if (!qid_has_mapping(sb->s_user_ns, qid))
650 ret = sb->s_qcop->get_dqblk(sb, qid, &qdq);
653 copy_to_xfs_dqblk(&fdq, &qdq, type, id);
654 if (copy_to_user(addr, &fdq, sizeof(fdq)))
660 * Return quota for next active quota >= this id, if any exists,
661 * otherwise return -ENOENT via ->get_nextdqblk.
663 static int quota_getnextxquota(struct super_block *sb, int type, qid_t id,
666 struct fs_disk_quota fdq;
672 if (!sb->s_qcop->get_nextdqblk)
674 qid = make_kqid(current_user_ns(), type, id);
675 if (!qid_has_mapping(sb->s_user_ns, qid))
677 ret = sb->s_qcop->get_nextdqblk(sb, &qid, &qdq);
680 id_out = from_kqid(current_user_ns(), qid);
681 copy_to_xfs_dqblk(&fdq, &qdq, type, id_out);
682 if (copy_to_user(addr, &fdq, sizeof(fdq)))
687 static int quota_rmxquota(struct super_block *sb, void __user *addr)
691 if (copy_from_user(&flags, addr, sizeof(flags)))
693 if (!sb->s_qcop->rm_xquota)
695 return sb->s_qcop->rm_xquota(sb, flags);
698 /* Copy parameters and call proper function */
699 static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
700 void __user *addr, const struct path *path)
704 if (type >= (XQM_COMMAND(cmd) ? XQM_MAXQUOTAS : MAXQUOTAS))
707 * Quota not supported on this fs? Check this before s_quota_types
708 * since they needn't be set if quota is not supported at all.
712 if (!(sb->s_quota_types & (1 << type)))
715 ret = check_quotactl_permission(sb, type, cmd, id);
721 return quota_quotaon(sb, type, id, path);
723 return quota_quotaoff(sb, type);
725 return quota_getfmt(sb, type, addr);
727 return quota_getinfo(sb, type, addr);
729 return quota_setinfo(sb, type, addr);
731 return quota_getquota(sb, type, id, addr);
733 return quota_getnextquota(sb, type, id, addr);
735 return quota_setquota(sb, type, id, addr);
737 if (!sb->s_qcop->quota_sync)
739 return sb->s_qcop->quota_sync(sb, type);
741 return quota_enable(sb, addr);
743 return quota_disable(sb, addr);
745 return quota_rmxquota(sb, addr);
747 return quota_getxstate(sb, addr);
749 return quota_getxstatev(sb, addr);
751 return quota_setxquota(sb, type, id, addr);
753 return quota_getxquota(sb, type, id, addr);
754 case Q_XGETNEXTQUOTA:
755 return quota_getnextxquota(sb, type, id, addr);
759 /* XFS quotas are fully coherent now, making this call a noop */
768 /* Return 1 if 'cmd' will block on frozen filesystem */
769 static int quotactl_cmd_write(int cmd)
772 * We cannot allow Q_GETQUOTA and Q_GETNEXTQUOTA without write access
773 * as dquot_acquire() may allocate space for new structure and OCFS2
774 * needs to increment on-disk use count.
783 case Q_XGETNEXTQUOTA:
789 #endif /* CONFIG_BLOCK */
791 /* Return true if quotactl command is manipulating quota on/off state */
792 static bool quotactl_cmd_onoff(int cmd)
794 return (cmd == Q_QUOTAON) || (cmd == Q_QUOTAOFF);
798 * look up a superblock on which quota ops will be performed
799 * - use the name of a block device to find the superblock thereon
801 static struct super_block *quotactl_block(const char __user *special, int cmd)
804 struct block_device *bdev;
805 struct super_block *sb;
806 struct filename *tmp = getname(special);
809 return ERR_CAST(tmp);
810 bdev = lookup_bdev(tmp->name);
813 return ERR_CAST(bdev);
814 if (quotactl_cmd_onoff(cmd))
815 sb = get_super_exclusive_thawed(bdev);
816 else if (quotactl_cmd_write(cmd))
817 sb = get_super_thawed(bdev);
819 sb = get_super(bdev);
822 return ERR_PTR(-ENODEV);
826 return ERR_PTR(-ENODEV);
831 * This is the system call interface. This communicates with
832 * the user-level programs. Currently this only supports diskquota
833 * calls. Maybe we need to add the process quotas etc. in the future,
834 * but we probably should use rlimits for that.
836 int kernel_quotactl(unsigned int cmd, const char __user *special,
837 qid_t id, void __user *addr)
840 struct super_block *sb = NULL;
841 struct path path, *pathp = NULL;
844 cmds = cmd >> SUBCMDSHIFT;
845 type = cmd & SUBCMDMASK;
848 * As a special case Q_SYNC can be called without a specific device.
849 * It will iterate all superblocks that have quota enabled and call
850 * the sync action on each of them.
854 return quota_sync_all(type);
859 * Path for quotaon has to be resolved before grabbing superblock
860 * because that gets s_umount sem which is also possibly needed by path
861 * resolution (think about autofs) and thus deadlocks could arise.
863 if (cmds == Q_QUOTAON) {
864 ret = user_path_at(AT_FDCWD, addr, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, &path);
866 pathp = ERR_PTR(ret);
871 sb = quotactl_block(special, cmds);
877 ret = do_quotactl(sb, type, cmds, id, addr, pathp);
879 if (!quotactl_cmd_onoff(cmds))
882 drop_super_exclusive(sb);
884 if (pathp && !IS_ERR(pathp))
889 SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special,
890 qid_t, id, void __user *, addr)
892 return kernel_quotactl(cmd, special, id, addr);