xref: /linux-6.15/include/linux/quota.h (revision bcefe12e)
1 /*
2  * Copyright (c) 1982, 1986 Regents of the University of California.
3  * All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Robert Elz at The University of Melbourne.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #ifndef _LINUX_QUOTA_
34 #define _LINUX_QUOTA_
35 
36 #include <linux/errno.h>
37 #include <linux/types.h>
38 
39 #define __DQUOT_VERSION__	"dquot_6.5.2"
40 
41 #define MAXQUOTAS 2
42 #define USRQUOTA  0		/* element used for user quotas */
43 #define GRPQUOTA  1		/* element used for group quotas */
44 
45 /*
46  * Definitions for the default names of the quotas files.
47  */
48 #define INITQFNAMES { \
49 	"user",    /* USRQUOTA */ \
50 	"group",   /* GRPQUOTA */ \
51 	"undefined", \
52 };
53 
54 /*
55  * Command definitions for the 'quotactl' system call.
56  * The commands are broken into a main command defined below
57  * and a subcommand that is used to convey the type of
58  * quota that is being manipulated (see above).
59  */
60 #define SUBCMDMASK  0x00ff
61 #define SUBCMDSHIFT 8
62 #define QCMD(cmd, type)  (((cmd) << SUBCMDSHIFT) | ((type) & SUBCMDMASK))
63 
64 #define Q_SYNC     0x800001	/* sync disk copy of a filesystems quotas */
65 #define Q_QUOTAON  0x800002	/* turn quotas on */
66 #define Q_QUOTAOFF 0x800003	/* turn quotas off */
67 #define Q_GETFMT   0x800004	/* get quota format used on given filesystem */
68 #define Q_GETINFO  0x800005	/* get information about quota files */
69 #define Q_SETINFO  0x800006	/* set information about quota files */
70 #define Q_GETQUOTA 0x800007	/* get user quota structure */
71 #define Q_SETQUOTA 0x800008	/* set user quota structure */
72 
73 /* Quota format type IDs */
74 #define	QFMT_VFS_OLD 1
75 #define	QFMT_VFS_V0 2
76 
77 /* Size of block in which space limits are passed through the quota
78  * interface */
79 #define QIF_DQBLKSIZE_BITS 10
80 #define QIF_DQBLKSIZE (1 << QIF_DQBLKSIZE_BITS)
81 
82 /*
83  * Quota structure used for communication with userspace via quotactl
84  * Following flags are used to specify which fields are valid
85  */
86 enum {
87 	QIF_BLIMITS_B = 0,
88 	QIF_SPACE_B,
89 	QIF_ILIMITS_B,
90 	QIF_INODES_B,
91 	QIF_BTIME_B,
92 	QIF_ITIME_B,
93 };
94 
95 #define QIF_BLIMITS	(1 << QIF_BLIMITS_B)
96 #define QIF_SPACE	(1 << QIF_SPACE_B)
97 #define QIF_ILIMITS	(1 << QIF_ILIMITS_B)
98 #define QIF_INODES	(1 << QIF_INODES_B)
99 #define QIF_BTIME	(1 << QIF_BTIME_B)
100 #define QIF_ITIME	(1 << QIF_ITIME_B)
101 #define QIF_LIMITS	(QIF_BLIMITS | QIF_ILIMITS)
102 #define QIF_USAGE	(QIF_SPACE | QIF_INODES)
103 #define QIF_TIMES	(QIF_BTIME | QIF_ITIME)
104 #define QIF_ALL		(QIF_LIMITS | QIF_USAGE | QIF_TIMES)
105 
106 struct if_dqblk {
107 	__u64 dqb_bhardlimit;
108 	__u64 dqb_bsoftlimit;
109 	__u64 dqb_curspace;
110 	__u64 dqb_ihardlimit;
111 	__u64 dqb_isoftlimit;
112 	__u64 dqb_curinodes;
113 	__u64 dqb_btime;
114 	__u64 dqb_itime;
115 	__u32 dqb_valid;
116 };
117 
118 /*
119  * Structure used for setting quota information about file via quotactl
120  * Following flags are used to specify which fields are valid
121  */
122 #define IIF_BGRACE	1
123 #define IIF_IGRACE	2
124 #define IIF_FLAGS	4
125 #define IIF_ALL		(IIF_BGRACE | IIF_IGRACE | IIF_FLAGS)
126 
127 struct if_dqinfo {
128 	__u64 dqi_bgrace;
129 	__u64 dqi_igrace;
130 	__u32 dqi_flags;
131 	__u32 dqi_valid;
132 };
133 
134 /*
135  * Definitions for quota netlink interface
136  */
137 #define QUOTA_NL_NOWARN 0
138 #define QUOTA_NL_IHARDWARN 1		/* Inode hardlimit reached */
139 #define QUOTA_NL_ISOFTLONGWARN 2 	/* Inode grace time expired */
140 #define QUOTA_NL_ISOFTWARN 3		/* Inode softlimit reached */
141 #define QUOTA_NL_BHARDWARN 4		/* Block hardlimit reached */
142 #define QUOTA_NL_BSOFTLONGWARN 5	/* Block grace time expired */
143 #define QUOTA_NL_BSOFTWARN 6		/* Block softlimit reached */
144 #define QUOTA_NL_IHARDBELOW 7		/* Usage got below inode hardlimit */
145 #define QUOTA_NL_ISOFTBELOW 8		/* Usage got below inode softlimit */
146 #define QUOTA_NL_BHARDBELOW 9		/* Usage got below block hardlimit */
147 #define QUOTA_NL_BSOFTBELOW 10		/* Usage got below block softlimit */
148 
149 enum {
150 	QUOTA_NL_C_UNSPEC,
151 	QUOTA_NL_C_WARNING,
152 	__QUOTA_NL_C_MAX,
153 };
154 #define QUOTA_NL_C_MAX (__QUOTA_NL_C_MAX - 1)
155 
156 enum {
157 	QUOTA_NL_A_UNSPEC,
158 	QUOTA_NL_A_QTYPE,
159 	QUOTA_NL_A_EXCESS_ID,
160 	QUOTA_NL_A_WARNING,
161 	QUOTA_NL_A_DEV_MAJOR,
162 	QUOTA_NL_A_DEV_MINOR,
163 	QUOTA_NL_A_CAUSED_ID,
164 	__QUOTA_NL_A_MAX,
165 };
166 #define QUOTA_NL_A_MAX (__QUOTA_NL_A_MAX - 1)
167 
168 
169 #ifdef __KERNEL__
170 #include <linux/list.h>
171 #include <linux/mutex.h>
172 #include <linux/rwsem.h>
173 #include <linux/spinlock.h>
174 #include <linux/wait.h>
175 
176 #include <linux/dqblk_xfs.h>
177 #include <linux/dqblk_v1.h>
178 #include <linux/dqblk_v2.h>
179 
180 #include <asm/atomic.h>
181 
182 typedef __kernel_uid32_t qid_t; /* Type in which we store ids in memory */
183 typedef long long qsize_t;	/* Type in which we store sizes */
184 
185 extern spinlock_t dq_data_lock;
186 
187 /* Maximal numbers of writes for quota operation (insert/delete/update)
188  * (over VFS all formats) */
189 #define DQUOT_INIT_ALLOC max(V1_INIT_ALLOC, V2_INIT_ALLOC)
190 #define DQUOT_INIT_REWRITE max(V1_INIT_REWRITE, V2_INIT_REWRITE)
191 #define DQUOT_DEL_ALLOC max(V1_DEL_ALLOC, V2_DEL_ALLOC)
192 #define DQUOT_DEL_REWRITE max(V1_DEL_REWRITE, V2_DEL_REWRITE)
193 
194 /*
195  * Data for one user/group kept in memory
196  */
197 struct mem_dqblk {
198 	qsize_t dqb_bhardlimit;	/* absolute limit on disk blks alloc */
199 	qsize_t dqb_bsoftlimit;	/* preferred limit on disk blks */
200 	qsize_t dqb_curspace;	/* current used space */
201 	qsize_t dqb_rsvspace;   /* current reserved space for delalloc*/
202 	qsize_t dqb_ihardlimit;	/* absolute limit on allocated inodes */
203 	qsize_t dqb_isoftlimit;	/* preferred inode limit */
204 	qsize_t dqb_curinodes;	/* current # allocated inodes */
205 	time_t dqb_btime;	/* time limit for excessive disk use */
206 	time_t dqb_itime;	/* time limit for excessive inode use */
207 };
208 
209 /*
210  * Data for one quotafile kept in memory
211  */
212 struct quota_format_type;
213 
214 struct mem_dqinfo {
215 	struct quota_format_type *dqi_format;
216 	int dqi_fmt_id;		/* Id of the dqi_format - used when turning
217 				 * quotas on after remount RW */
218 	struct list_head dqi_dirty_list;	/* List of dirty dquots */
219 	unsigned long dqi_flags;
220 	unsigned int dqi_bgrace;
221 	unsigned int dqi_igrace;
222 	qsize_t dqi_maxblimit;
223 	qsize_t dqi_maxilimit;
224 	void *dqi_priv;
225 };
226 
227 struct super_block;
228 
229 #define DQF_MASK 0xffff		/* Mask for format specific flags */
230 #define DQF_INFO_DIRTY_B 16
231 #define DQF_INFO_DIRTY (1 << DQF_INFO_DIRTY_B)	/* Is info dirty? */
232 
233 extern void mark_info_dirty(struct super_block *sb, int type);
234 static inline int info_dirty(struct mem_dqinfo *info)
235 {
236 	return test_bit(DQF_INFO_DIRTY_B, &info->dqi_flags);
237 }
238 
239 struct dqstats {
240 	int lookups;
241 	int drops;
242 	int reads;
243 	int writes;
244 	int cache_hits;
245 	int allocated_dquots;
246 	int free_dquots;
247 	int syncs;
248 };
249 
250 extern struct dqstats dqstats;
251 
252 #define DQ_MOD_B	0	/* dquot modified since read */
253 #define DQ_BLKS_B	1	/* uid/gid has been warned about blk limit */
254 #define DQ_INODES_B	2	/* uid/gid has been warned about inode limit */
255 #define DQ_FAKE_B	3	/* no limits only usage */
256 #define DQ_READ_B	4	/* dquot was read into memory */
257 #define DQ_ACTIVE_B	5	/* dquot is active (dquot_release not called) */
258 #define DQ_LASTSET_B	6	/* Following 6 bits (see QIF_) are reserved\
259 				 * for the mask of entries set via SETQUOTA\
260 				 * quotactl. They are set under dq_data_lock\
261 				 * and the quota format handling dquot can\
262 				 * clear them when it sees fit. */
263 
264 struct dquot {
265 	struct hlist_node dq_hash;	/* Hash list in memory */
266 	struct list_head dq_inuse;	/* List of all quotas */
267 	struct list_head dq_free;	/* Free list element */
268 	struct list_head dq_dirty;	/* List of dirty dquots */
269 	struct mutex dq_lock;		/* dquot IO lock */
270 	atomic_t dq_count;		/* Use count */
271 	wait_queue_head_t dq_wait_unused;	/* Wait queue for dquot to become unused */
272 	struct super_block *dq_sb;	/* superblock this applies to */
273 	unsigned int dq_id;		/* ID this applies to (uid, gid) */
274 	loff_t dq_off;			/* Offset of dquot on disk */
275 	unsigned long dq_flags;		/* See DQ_* */
276 	short dq_type;			/* Type of quota */
277 	struct mem_dqblk dq_dqb;	/* Diskquota usage */
278 };
279 
280 #define QUOTA_OK          0
281 #define NO_QUOTA          1
282 
283 /* Operations which must be implemented by each quota format */
284 struct quota_format_ops {
285 	int (*check_quota_file)(struct super_block *sb, int type);	/* Detect whether file is in our format */
286 	int (*read_file_info)(struct super_block *sb, int type);	/* Read main info about file - called on quotaon() */
287 	int (*write_file_info)(struct super_block *sb, int type);	/* Write main info about file */
288 	int (*free_file_info)(struct super_block *sb, int type);	/* Called on quotaoff() */
289 	int (*read_dqblk)(struct dquot *dquot);		/* Read structure for one user */
290 	int (*commit_dqblk)(struct dquot *dquot);	/* Write structure for one user */
291 	int (*release_dqblk)(struct dquot *dquot);	/* Called when last reference to dquot is being dropped */
292 };
293 
294 /* Operations working with dquots */
295 struct dquot_operations {
296 	int (*initialize) (struct inode *, int);
297 	int (*drop) (struct inode *);
298 	int (*alloc_space) (struct inode *, qsize_t, int);
299 	int (*alloc_inode) (const struct inode *, qsize_t);
300 	int (*free_space) (struct inode *, qsize_t);
301 	int (*free_inode) (const struct inode *, qsize_t);
302 	int (*transfer) (struct inode *, struct iattr *);
303 	int (*write_dquot) (struct dquot *);		/* Ordinary dquot write */
304 	struct dquot *(*alloc_dquot)(struct super_block *, int);	/* Allocate memory for new dquot */
305 	void (*destroy_dquot)(struct dquot *);		/* Free memory for dquot */
306 	int (*acquire_dquot) (struct dquot *);		/* Quota is going to be created on disk */
307 	int (*release_dquot) (struct dquot *);		/* Quota is going to be deleted from disk */
308 	int (*mark_dirty) (struct dquot *);		/* Dquot is marked dirty */
309 	int (*write_info) (struct super_block *, int);	/* Write of quota "superblock" */
310 	/* reserve quota for delayed block allocation */
311 	int (*reserve_space) (struct inode *, qsize_t, int);
312 	/* claim reserved quota for delayed alloc */
313 	int (*claim_space) (struct inode *, qsize_t);
314 	/* release rsved quota for delayed alloc */
315 	void (*release_rsv) (struct inode *, qsize_t);
316 	/* get reserved quota for delayed alloc */
317 	qsize_t (*get_reserved_space) (struct inode *);
318 };
319 
320 /* Operations handling requests from userspace */
321 struct quotactl_ops {
322 	int (*quota_on)(struct super_block *, int, int, char *, int);
323 	int (*quota_off)(struct super_block *, int, int);
324 	int (*quota_sync)(struct super_block *, int);
325 	int (*get_info)(struct super_block *, int, struct if_dqinfo *);
326 	int (*set_info)(struct super_block *, int, struct if_dqinfo *);
327 	int (*get_dqblk)(struct super_block *, int, qid_t, struct if_dqblk *);
328 	int (*set_dqblk)(struct super_block *, int, qid_t, struct if_dqblk *);
329 	int (*get_xstate)(struct super_block *, struct fs_quota_stat *);
330 	int (*set_xstate)(struct super_block *, unsigned int, int);
331 	int (*get_xquota)(struct super_block *, int, qid_t, struct fs_disk_quota *);
332 	int (*set_xquota)(struct super_block *, int, qid_t, struct fs_disk_quota *);
333 };
334 
335 struct quota_format_type {
336 	int qf_fmt_id;	/* Quota format id */
337 	struct quota_format_ops *qf_ops;	/* Operations of format */
338 	struct module *qf_owner;		/* Module implementing quota format */
339 	struct quota_format_type *qf_next;
340 };
341 
342 /* Quota state flags - they actually come in two flavors - for users and groups */
343 enum {
344 	_DQUOT_USAGE_ENABLED = 0,		/* Track disk usage for users */
345 	_DQUOT_LIMITS_ENABLED,			/* Enforce quota limits for users */
346 	_DQUOT_SUSPENDED,			/* User diskquotas are off, but
347 						 * we have necessary info in
348 						 * memory to turn them on */
349 	_DQUOT_STATE_FLAGS
350 };
351 #define DQUOT_USAGE_ENABLED	(1 << _DQUOT_USAGE_ENABLED)
352 #define DQUOT_LIMITS_ENABLED	(1 << _DQUOT_LIMITS_ENABLED)
353 #define DQUOT_SUSPENDED		(1 << _DQUOT_SUSPENDED)
354 #define DQUOT_STATE_FLAGS	(DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED | \
355 				 DQUOT_SUSPENDED)
356 /* Other quota flags */
357 #define DQUOT_QUOTA_SYS_FILE	(1 << 6)	/* Quota file is a special
358 						 * system file and user cannot
359 						 * touch it. Filesystem is
360 						 * responsible for setting
361 						 * S_NOQUOTA, S_NOATIME flags
362 						 */
363 #define DQUOT_NEGATIVE_USAGE	(1 << 7)	/* Allow negative quota usage */
364 
365 static inline unsigned int dquot_state_flag(unsigned int flags, int type)
366 {
367 	if (type == USRQUOTA)
368 		return flags;
369 	return flags << _DQUOT_STATE_FLAGS;
370 }
371 
372 static inline unsigned int dquot_generic_flag(unsigned int flags, int type)
373 {
374 	if (type == USRQUOTA)
375 		return flags;
376 	return flags >> _DQUOT_STATE_FLAGS;
377 }
378 
379 struct quota_info {
380 	unsigned int flags;			/* Flags for diskquotas on this device */
381 	struct mutex dqio_mutex;		/* lock device while I/O in progress */
382 	struct mutex dqonoff_mutex;		/* Serialize quotaon & quotaoff */
383 	struct rw_semaphore dqptr_sem;		/* serialize ops using quota_info struct, pointers from inode to dquots */
384 	struct inode *files[MAXQUOTAS];		/* inodes of quotafiles */
385 	struct mem_dqinfo info[MAXQUOTAS];	/* Information for each quota type */
386 	struct quota_format_ops *ops[MAXQUOTAS];	/* Operations for each type */
387 };
388 
389 int register_quota_format(struct quota_format_type *fmt);
390 void unregister_quota_format(struct quota_format_type *fmt);
391 
392 struct quota_module_name {
393 	int qm_fmt_id;
394 	char *qm_mod_name;
395 };
396 
397 #define INIT_QUOTA_MODULE_NAMES {\
398 	{QFMT_VFS_OLD, "quota_v1"},\
399 	{QFMT_VFS_V0, "quota_v2"},\
400 	{0, NULL}}
401 
402 #else
403 
404 # /* nodep */ include <sys/cdefs.h>
405 
406 __BEGIN_DECLS
407 long quotactl __P ((unsigned int, const char *, int, caddr_t));
408 __END_DECLS
409 
410 #endif /* __KERNEL__ */
411 #endif /* _QUOTA_ */
412