2 * Quota code necessary even when VFS quota support is not compiled
3 * into the kernel. The interesting stuff is over in dquot.c, here
4 * we have symbols for initial quotactl(2) handling, the sysctl(2)
5 * variables, etc - things needed even when quota support disabled.
9 #include <linux/namei.h>
10 #include <linux/slab.h>
11 #include <asm/current.h>
12 #include <asm/uaccess.h>
13 #include <linux/compat.h>
14 #include <linux/kernel.h>
15 #include <linux/security.h>
16 #include <linux/syscalls.h>
17 #include <linux/buffer_head.h>
18 #include <linux/capability.h>
19 #include <linux/quotaops.h>
20 #include <linux/types.h>
22 /* Check validity of generic quotactl commands */
23 static int generic_quotactl_valid(struct super_block *sb, int type, int cmd, qid_t id)
25 if (type >= MAXQUOTAS)
27 if (!sb && cmd != Q_SYNC)
29 /* Is operation supported? */
30 if (sb && !sb->s_qcop)
37 if (!sb->s_qcop->quota_on)
41 if (!sb->s_qcop->quota_off)
45 if (!sb->s_qcop->set_info)
49 if (!sb->s_qcop->get_info)
53 if (!sb->s_qcop->set_dqblk)
57 if (!sb->s_qcop->get_dqblk)
61 if (sb && !sb->s_qcop->quota_sync)
68 /* Is quota turned on for commands which need it? */
76 /* This is just informative test so we are satisfied without a lock */
77 if (!sb_has_quota_enabled(sb, type))
81 /* Check privileges */
82 if (cmd == Q_GETQUOTA) {
83 if (((type == USRQUOTA && current->euid != id) ||
84 (type == GRPQUOTA && !in_egroup_p(id))) &&
85 !capable(CAP_SYS_ADMIN))
88 else if (cmd != Q_GETFMT && cmd != Q_SYNC && cmd != Q_GETINFO)
89 if (!capable(CAP_SYS_ADMIN))
95 /* Check validity of XFS Quota Manager commands */
96 static int xqm_quotactl_valid(struct super_block *sb, int type, int cmd, qid_t id)
98 if (type >= XQM_MAXQUOTAS)
109 if (!sb->s_qcop->set_xstate)
113 if (!sb->s_qcop->get_xstate)
117 if (!sb->s_qcop->set_xquota)
121 if (!sb->s_qcop->get_xquota)
125 if (!sb->s_qcop->quota_sync)
132 /* Check privileges */
133 if (cmd == Q_XGETQUOTA) {
134 if (((type == XQM_USRQUOTA && current->euid != id) ||
135 (type == XQM_GRPQUOTA && !in_egroup_p(id))) &&
136 !capable(CAP_SYS_ADMIN))
138 } else if (cmd != Q_XGETQSTAT && cmd != Q_XQUOTASYNC) {
139 if (!capable(CAP_SYS_ADMIN))
146 static int check_quotactl_valid(struct super_block *sb, int type, int cmd, qid_t id)
150 if (XQM_COMMAND(cmd))
151 error = xqm_quotactl_valid(sb, type, cmd, id);
153 error = generic_quotactl_valid(sb, type, cmd, id);
155 error = security_quotactl(cmd, type, id, sb);
159 static void quota_sync_sb(struct super_block *sb, int type)
163 sb->s_qcop->quota_sync(sb, type);
164 /* This is not very clever (and fast) but currently I don't know about
165 * any other simple way of getting quota data to disk and we must get
166 * them there for userspace to be visible... */
167 if (sb->s_op->sync_fs)
168 sb->s_op->sync_fs(sb, 1);
169 sync_blockdev(sb->s_bdev);
172 * Now when everything is written we can discard the pagecache so
173 * that userspace sees the changes.
175 mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
176 for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
177 if (type != -1 && cnt != type)
179 if (!sb_has_quota_enabled(sb, cnt))
181 mutex_lock_nested(&sb_dqopt(sb)->files[cnt]->i_mutex, I_MUTEX_QUOTA);
182 truncate_inode_pages(&sb_dqopt(sb)->files[cnt]->i_data, 0);
183 mutex_unlock(&sb_dqopt(sb)->files[cnt]->i_mutex);
185 mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
188 void sync_dquots(struct super_block *sb, int type)
193 if (sb->s_qcop->quota_sync)
194 quota_sync_sb(sb, type);
200 list_for_each_entry(sb, &super_blocks, s_list) {
201 /* This test just improves performance so it needn't be reliable... */
202 for (cnt = 0, dirty = 0; cnt < MAXQUOTAS; cnt++)
203 if ((type == cnt || type == -1) && sb_has_quota_enabled(sb, cnt)
204 && info_any_dirty(&sb_dqopt(sb)->info[cnt]))
209 spin_unlock(&sb_lock);
210 down_read(&sb->s_umount);
211 if (sb->s_root && sb->s_qcop->quota_sync)
212 quota_sync_sb(sb, type);
213 up_read(&sb->s_umount);
215 if (__put_super_and_need_restart(sb))
218 spin_unlock(&sb_lock);
221 /* Copy parameters and call proper function */
222 static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id, void __user *addr)
230 if (IS_ERR(pathname = getname(addr)))
231 return PTR_ERR(pathname);
232 ret = sb->s_qcop->quota_on(sb, type, id, pathname);
237 return sb->s_qcop->quota_off(sb, type);
242 down_read(&sb_dqopt(sb)->dqptr_sem);
243 if (!sb_has_quota_enabled(sb, type)) {
244 up_read(&sb_dqopt(sb)->dqptr_sem);
247 fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id;
248 up_read(&sb_dqopt(sb)->dqptr_sem);
249 if (copy_to_user(addr, &fmt, sizeof(fmt)))
254 struct if_dqinfo info;
256 if ((ret = sb->s_qcop->get_info(sb, type, &info)))
258 if (copy_to_user(addr, &info, sizeof(info)))
263 struct if_dqinfo info;
265 if (copy_from_user(&info, addr, sizeof(info)))
267 return sb->s_qcop->set_info(sb, type, &info);
272 if ((ret = sb->s_qcop->get_dqblk(sb, type, id, &idq)))
274 if (copy_to_user(addr, &idq, sizeof(idq)))
281 if (copy_from_user(&idq, addr, sizeof(idq)))
283 return sb->s_qcop->set_dqblk(sb, type, id, &idq);
286 sync_dquots(sb, type);
294 if (copy_from_user(&flags, addr, sizeof(flags)))
296 return sb->s_qcop->set_xstate(sb, flags, cmd);
299 struct fs_quota_stat fqs;
301 if ((ret = sb->s_qcop->get_xstate(sb, &fqs)))
303 if (copy_to_user(addr, &fqs, sizeof(fqs)))
308 struct fs_disk_quota fdq;
310 if (copy_from_user(&fdq, addr, sizeof(fdq)))
312 return sb->s_qcop->set_xquota(sb, type, id, &fdq);
315 struct fs_disk_quota fdq;
317 if ((ret = sb->s_qcop->get_xquota(sb, type, id, &fdq)))
319 if (copy_to_user(addr, &fdq, sizeof(fdq)))
324 return sb->s_qcop->quota_sync(sb, type);
325 /* We never reach here unless validity check is broken */
333 * look up a superblock on which quota ops will be performed
334 * - use the name of a block device to find the superblock thereon
336 static inline struct super_block *quotactl_block(const char __user *special)
339 struct block_device *bdev;
340 struct super_block *sb;
341 char *tmp = getname(special);
344 return ERR_PTR(PTR_ERR(tmp));
345 bdev = lookup_bdev(tmp);
348 return ERR_PTR(PTR_ERR(bdev));
349 sb = get_super(bdev);
352 return ERR_PTR(-ENODEV);
356 return ERR_PTR(-ENODEV);
361 * This is the system call interface. This communicates with
362 * the user-level programs. Currently this only supports diskquota
363 * calls. Maybe we need to add the process quotas etc. in the future,
364 * but we probably should use rlimits for that.
366 asmlinkage long sys_quotactl(unsigned int cmd, const char __user *special, qid_t id, void __user *addr)
369 struct super_block *sb = NULL;
372 cmds = cmd >> SUBCMDSHIFT;
373 type = cmd & SUBCMDMASK;
375 if (cmds != Q_SYNC || special) {
376 sb = quotactl_block(special);
381 ret = check_quotactl_valid(sb, type, cmds, id);
383 ret = do_quotactl(sb, type, cmds, id, addr);
390 #if defined(CONFIG_COMPAT_FOR_U64_ALIGNMENT)
392 * This code works only for 32 bit quota tools over 64 bit OS (x86_64, ia64)
393 * and is necessary due to alignment problems.
395 struct compat_if_dqblk {
396 compat_u64 dqb_bhardlimit;
397 compat_u64 dqb_bsoftlimit;
398 compat_u64 dqb_curspace;
399 compat_u64 dqb_ihardlimit;
400 compat_u64 dqb_isoftlimit;
401 compat_u64 dqb_curinodes;
402 compat_u64 dqb_btime;
403 compat_u64 dqb_itime;
404 compat_uint_t dqb_valid;
408 struct compat_fs_qfilestat {
409 compat_u64 dqb_bhardlimit;
410 compat_u64 qfs_nblks;
411 compat_uint_t qfs_nextents;
414 struct compat_fs_quota_stat {
418 struct compat_fs_qfilestat qs_uquota;
419 struct compat_fs_qfilestat qs_gquota;
420 compat_uint_t qs_incoredqs;
421 compat_int_t qs_btimelimit;
422 compat_int_t qs_itimelimit;
423 compat_int_t qs_rtbtimelimit;
428 asmlinkage long sys32_quotactl(unsigned int cmd, const char __user *special,
429 qid_t id, void __user *addr)
432 struct if_dqblk __user *dqblk;
433 struct compat_if_dqblk __user *compat_dqblk;
434 struct fs_quota_stat __user *fsqstat;
435 struct compat_fs_quota_stat __user *compat_fsqstat;
440 cmds = cmd >> SUBCMDSHIFT;
444 dqblk = compat_alloc_user_space(sizeof(struct if_dqblk));
446 ret = sys_quotactl(cmd, special, id, dqblk);
449 if (copy_in_user(compat_dqblk, dqblk, sizeof(*compat_dqblk)) ||
450 get_user(data, &dqblk->dqb_valid) ||
451 put_user(data, &compat_dqblk->dqb_valid))
455 dqblk = compat_alloc_user_space(sizeof(struct if_dqblk));
458 if (copy_in_user(dqblk, compat_dqblk, sizeof(*compat_dqblk)) ||
459 get_user(data, &compat_dqblk->dqb_valid) ||
460 put_user(data, &dqblk->dqb_valid))
462 ret = sys_quotactl(cmd, special, id, dqblk);
465 fsqstat = compat_alloc_user_space(sizeof(struct fs_quota_stat));
466 compat_fsqstat = addr;
467 ret = sys_quotactl(cmd, special, id, fsqstat);
471 /* Copying qs_version, qs_flags, qs_pad */
472 if (copy_in_user(compat_fsqstat, fsqstat,
473 offsetof(struct compat_fs_quota_stat, qs_uquota)))
475 /* Copying qs_uquota */
476 if (copy_in_user(&compat_fsqstat->qs_uquota,
478 sizeof(compat_fsqstat->qs_uquota)) ||
479 get_user(data, &fsqstat->qs_uquota.qfs_nextents) ||
480 put_user(data, &compat_fsqstat->qs_uquota.qfs_nextents))
482 /* Copying qs_gquota */
483 if (copy_in_user(&compat_fsqstat->qs_gquota,
485 sizeof(compat_fsqstat->qs_gquota)) ||
486 get_user(data, &fsqstat->qs_gquota.qfs_nextents) ||
487 put_user(data, &compat_fsqstat->qs_gquota.qfs_nextents))
489 /* Copying the rest */
490 if (copy_in_user(&compat_fsqstat->qs_incoredqs,
491 &fsqstat->qs_incoredqs,
492 sizeof(struct compat_fs_quota_stat) -
493 offsetof(struct compat_fs_quota_stat, qs_incoredqs)) ||
494 get_user(xdata, &fsqstat->qs_iwarnlimit) ||
495 put_user(xdata, &compat_fsqstat->qs_iwarnlimit))
500 ret = sys_quotactl(cmd, special, id, addr);