quotaio.c revision 8f00911a21f4e95de84c60e09cc4df173e5b6701 
1/** quotaio.c
2 *
3 * Generic IO operations on quotafiles
4 * Jan Kara <jack@suse.cz> - sponsored by SuSE CR
5 * Aditya Kali <adityakali@google.com> - Ported to e2fsprogs
6 */
7
8#include "config.h"
9#include <stdio.h>
10#include <errno.h>
11#include <string.h>
12#include <unistd.h>
13#include <stdlib.h>
14#include <time.h>
15#include <sys/types.h>
16#include <sys/stat.h>
17#include <sys/file.h>
18
19#include "common.h"
20#include "quotaio.h"
21
22static const char * const extensions[MAXQUOTAS] = {"user", "group"};
23static const char * const basenames[] = {
24	"",		/* undefined */
25	"quota",	/* QFMT_VFS_OLD */
26	"aquota",	/* QFMT_VFS_V0 */
27	"",		/* QFMT_OCFS2 */
28	"aquota"	/* QFMT_VFS_V1 */
29};
30
31/* Header in all newer quotafiles */
32struct disk_dqheader {
33	u_int32_t dqh_magic;
34	u_int32_t dqh_version;
35} __attribute__ ((packed));
36
37/**
38 * Convert type of quota to written representation
39 */
40const char *type2name(int type)
41{
42	return extensions[type];
43}
44
45/**
46 * Creates a quota file name for given type and format.
47 */
48const char *quota_get_qf_name(int type, int fmt, char *buf)
49{
50	if (!buf)
51		return NULL;
52	snprintf(buf, QUOTA_NAME_LEN, "%s.%s",
53		 basenames[fmt], extensions[type]);
54
55	return buf;
56}
57
58const char *quota_get_qf_path(const char *mntpt, int qtype, int fmt,
59			      char *path_buf, size_t path_buf_size)
60{
61	char qf_name[QUOTA_NAME_LEN];
62
63	if (!mntpt || !path_buf || !path_buf_size)
64		return NULL;
65
66	strncpy(path_buf, mntpt, path_buf_size);
67	strncat(path_buf, "/", 1);
68	strncat(path_buf, quota_get_qf_name(qtype, fmt, qf_name),
69		path_buf_size - strlen(path_buf));
70
71	return path_buf;
72}
73
74/*
75 * Set grace time if needed
76 */
77void update_grace_times(struct dquot *q)
78{
79	time_t now;
80
81	time(&now);
82	if (q->dq_dqb.dqb_bsoftlimit && toqb(q->dq_dqb.dqb_curspace) >
83			q->dq_dqb.dqb_bsoftlimit) {
84		if (!q->dq_dqb.dqb_btime)
85			q->dq_dqb.dqb_btime =
86				now + q->dq_h->qh_info.dqi_bgrace;
87	} else {
88		q->dq_dqb.dqb_btime = 0;
89	}
90
91	if (q->dq_dqb.dqb_isoftlimit && q->dq_dqb.dqb_curinodes >
92			q->dq_dqb.dqb_isoftlimit) {
93		if (!q->dq_dqb.dqb_itime)
94				q->dq_dqb.dqb_itime =
95					now + q->dq_h->qh_info.dqi_igrace;
96	} else {
97		q->dq_dqb.dqb_itime = 0;
98	}
99}
100
101static int release_blocks_proc(ext2_filsys fs, blk64_t *blocknr,
102			       e2_blkcnt_t blockcnt EXT2FS_ATTR((unused)),
103			       blk64_t ref_block EXT2FS_ATTR((unused)),
104			       int ref_offset EXT2FS_ATTR((unused)),
105			       void *private EXT2FS_ATTR((unused)))
106{
107	blk64_t	block;
108
109	block = *blocknr;
110	ext2fs_block_alloc_stats2(fs, block, -1);
111	return 0;
112}
113
114static int compute_num_blocks_proc(ext2_filsys fs, blk64_t *blocknr,
115			       e2_blkcnt_t blockcnt EXT2FS_ATTR((unused)),
116			       blk64_t ref_block EXT2FS_ATTR((unused)),
117			       int ref_offset EXT2FS_ATTR((unused)),
118			       void *private)
119{
120	blk64_t	block;
121	blk64_t *num_blocks = private;
122
123	*num_blocks += 1;
124	return 0;
125}
126
127errcode_t quota_inode_truncate(ext2_filsys fs, ext2_ino_t ino)
128{
129	struct ext2_inode inode;
130	errcode_t err;
131	int i;
132
133	if ((err = ext2fs_read_inode(fs, ino, &inode)))
134		return err;
135
136	inode.i_dtime = fs->now ? fs->now : time(0);
137	if (!ext2fs_inode_has_valid_blocks2(fs, &inode))
138		return 0;
139
140	ext2fs_block_iterate3(fs, ino, BLOCK_FLAG_READ_ONLY, NULL,
141			      release_blocks_proc, NULL);
142
143	memset(&inode, 0, sizeof(struct ext2_inode));
144	err = ext2fs_write_inode(fs, ino, &inode);
145	return err;
146}
147
148static ext2_off64_t compute_inode_size(ext2_filsys fs, ext2_ino_t ino)
149{
150	blk64_t num_blocks = 0;
151
152	ext2fs_block_iterate3(fs, ino,
153			      BLOCK_FLAG_READ_ONLY,
154			      NULL,
155			      compute_num_blocks_proc,
156			      &num_blocks);
157	return num_blocks * fs->blocksize;
158}
159
160/* Functions to read/write quota file. */
161static unsigned int quota_write_nomount(struct quota_file *qf,
162					ext2_loff_t offset,
163					void *buf, unsigned int size)
164{
165	ext2_file_t	e2_file = qf->e2_file;
166	unsigned int	bytes_written = 0;
167	errcode_t	err;
168
169	err = ext2fs_file_llseek(e2_file, offset, EXT2_SEEK_SET, NULL);
170	if (err) {
171		log_err("ext2fs_file_llseek failed: %ld", err);
172		return 0;
173	}
174
175	err = ext2fs_file_write(e2_file, buf, size, &bytes_written);
176	if (err) {
177		log_err("ext2fs_file_write failed: %ld", err);
178		return 0;
179	}
180
181	/* Correct inode.i_size is set in end_io. */
182	return bytes_written;
183}
184
185static unsigned int quota_read_nomount(struct quota_file *qf,
186				       ext2_loff_t offset,
187				       void *buf, unsigned int size)
188{
189	ext2_file_t	e2_file = qf->e2_file;
190	unsigned int	bytes_read = 0;
191	errcode_t	err;
192
193	err = ext2fs_file_llseek(e2_file, offset, EXT2_SEEK_SET, NULL);
194	if (err) {
195		log_err("ext2fs_file_llseek failed: %ld", err);
196		return 0;
197	}
198
199	err = ext2fs_file_read(e2_file, buf, size, &bytes_read);
200	if (err) {
201		log_err("ext2fs_file_read failed: %ld", err);
202		return 0;
203	}
204
205	return bytes_read;
206}
207
208/*
209 * Detect quota format and initialize quota IO
210 */
211errcode_t quota_file_open(struct quota_handle *h, ext2_filsys fs,
212			  ext2_ino_t qf_ino, int type, int fmt, int flags)
213{
214	ext2_file_t e2_file;
215	errcode_t err;
216
217	if (fmt == -1)
218		fmt = QFMT_VFS_V1;
219
220	err = ext2fs_read_bitmaps(fs);
221	if (err)
222		return err;
223
224	log_debug("Opening quota ino=%lu, type=%d", qf_ino, type);
225	err = ext2fs_file_open(fs, qf_ino, flags, &e2_file);
226	if (err) {
227		log_err("ext2fs_file_open failed: %s", error_message(err));
228		return err;
229	}
230	h->qh_qf.e2_file = e2_file;
231
232	h->qh_qf.fs = fs;
233	h->qh_qf.ino = qf_ino;
234	h->e2fs_write = quota_write_nomount;
235	h->e2fs_read = quota_read_nomount;
236	h->qh_io_flags = 0;
237	h->qh_type = type;
238	h->qh_fmt = fmt;
239	memset(&h->qh_info, 0, sizeof(h->qh_info));
240	h->qh_ops = &quotafile_ops_2;
241
242	if (h->qh_ops->check_file &&
243	    (h->qh_ops->check_file(h, type, fmt) == 0)) {
244		log_err("qh_ops->check_file failed", "");
245		ext2fs_file_close(e2_file);
246		return -1;
247	}
248
249	if (h->qh_ops->init_io && (h->qh_ops->init_io(h) < 0)) {
250		log_err("qh_ops->init_io failed", "");
251		ext2fs_file_close(e2_file);
252		return -1;
253	}
254
255	return 0;
256}
257
258static errcode_t quota_inode_init_new(ext2_filsys fs, ext2_ino_t ino)
259{
260	struct ext2_inode inode;
261	errcode_t err = 0;
262
263	err = ext2fs_read_inode(fs, ino, &inode);
264	if (err) {
265		log_err("ex2fs_read_inode failed", "");
266		return err;
267	}
268
269	if (EXT2_I_SIZE(&inode))
270		quota_inode_truncate(fs, ino);
271
272	memset(&inode, 0, sizeof(struct ext2_inode));
273	ext2fs_iblk_set(fs, &inode, 0);
274	inode.i_atime = inode.i_mtime =
275		inode.i_ctime = fs->now ? fs->now : time(0);
276	inode.i_links_count = 1;
277	inode.i_mode = LINUX_S_IFREG | 0600;
278	inode.i_flags |= EXT2_IMMUTABLE_FL;
279	if (fs->super->s_feature_incompat &
280			EXT3_FEATURE_INCOMPAT_EXTENTS)
281		inode.i_flags |= EXT4_EXTENTS_FL;
282
283	err = ext2fs_write_new_inode(fs, ino, &inode);
284	if (err) {
285		log_err("ext2fs_write_new_inode failed: %ld", err);
286		return err;
287	}
288	return err;
289}
290
291/*
292 * Create new quotafile of specified format on given filesystem
293 */
294errcode_t quota_file_create(struct quota_handle *h, ext2_filsys fs, int type, int fmt)
295{
296	ext2_file_t e2_file;
297	int err;
298	unsigned long qf_inum;
299
300	if (fmt == -1)
301		fmt = QFMT_VFS_V1;
302
303	h->qh_qf.fs = fs;
304	if (type == USRQUOTA)
305		qf_inum = EXT4_USR_QUOTA_INO;
306	else if (type == GRPQUOTA)
307		qf_inum = EXT4_GRP_QUOTA_INO;
308	else
309		return -1;
310
311	err = ext2fs_read_bitmaps(fs);
312	if (err)
313		goto out_err;
314
315	err = quota_inode_init_new(fs, qf_inum);
316	if (err) {
317		log_err("init_new_quota_inode failed", "");
318		goto out_err;
319	}
320	h->qh_qf.ino = qf_inum;
321	h->e2fs_write = quota_write_nomount;
322	h->e2fs_read = quota_read_nomount;
323
324	log_debug("Creating quota ino=%lu, type=%d", qf_inum, type);
325	err = ext2fs_file_open(fs, qf_inum,
326			EXT2_FILE_WRITE | EXT2_FILE_CREATE, &e2_file);
327	if (err) {
328		log_err("ext2fs_file_open failed: %d", err);
329		goto out_err;
330	}
331	h->qh_qf.e2_file = e2_file;
332
333	h->qh_io_flags = 0;
334	h->qh_type = type;
335	h->qh_fmt = fmt;
336	memset(&h->qh_info, 0, sizeof(h->qh_info));
337	h->qh_ops = &quotafile_ops_2;
338
339	if (h->qh_ops->new_io && (h->qh_ops->new_io(h) < 0)) {
340		log_err("qh_ops->new_io failed", "");
341		goto out_err1;
342	}
343
344	return 0;
345
346out_err1:
347	ext2fs_file_close(e2_file);
348out_err:
349
350	if (qf_inum)
351		quota_inode_truncate(fs, qf_inum);
352
353	return -1;
354}
355
356/*
357 * Close quotafile and release handle
358 */
359errcode_t quota_file_close(struct quota_handle *h)
360{
361	if (h->qh_io_flags & IOFL_INFODIRTY) {
362		if (h->qh_ops->write_info && h->qh_ops->write_info(h) < 0)
363			return -1;
364		h->qh_io_flags &= ~IOFL_INFODIRTY;
365	}
366
367	if (h->qh_ops->end_io && h->qh_ops->end_io(h) < 0)
368		return -1;
369	if (h->qh_qf.e2_file) {
370		ext2fs_file_flush(h->qh_qf.e2_file);
371		ext2fs_file_set_size2(h->qh_qf.e2_file,
372			compute_inode_size(h->qh_qf.fs, h->qh_qf.ino));
373		ext2fs_file_close(h->qh_qf.e2_file);
374	}
375
376	return 0;
377}
378
379/*
380 * Create empty quota structure
381 */
382struct dquot *get_empty_dquot(void)
383{
384	struct dquot *dquot;
385
386	if (ext2fs_get_memzero(sizeof(struct dquot), &dquot)) {
387		log_err("Failed to allocate dquot", "");
388		return NULL;
389	}
390
391	dquot->dq_id = -1;
392	return dquot;
393}
394