quotaio.c revision 36e4e21f511423450285568ceb26b3ddb233e286 
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 <sys/types.h>
15#include <sys/stat.h>
16#include <sys/file.h>
17
18#include "common.h"
19#include "quotaio.h"
20
21static const char extensions[MAXQUOTAS + 2][20] = INITQFNAMES;
22static const char * const basenames[] = {
23	"",		/* undefined */
24	"quota",	/* QFMT_VFS_OLD */
25	"aquota",	/* QFMT_VFS_V0 */
26	"",		/* QFMT_OCFS2 */
27	"aquota"	/* QFMT_VFS_V1 */
28};
29
30static const char * const fmtnames[] = {
31	"vfsold",
32	"vfsv0",
33	"vfsv1",
34	"rpc",
35	"xfs"
36};
37
38/* Header in all newer quotafiles */
39struct disk_dqheader {
40	u_int32_t dqh_magic;
41	u_int32_t dqh_version;
42} __attribute__ ((packed));
43
44/**
45 * Convert type of quota to written representation
46 */
47const char *type2name(int type)
48{
49	return extensions[type];
50}
51
52/*
53 * Set grace time if needed
54 */
55void update_grace_times(struct dquot *q)
56{
57	time_t now;
58
59	time(&now);
60	if (q->dq_dqb.dqb_bsoftlimit && toqb(q->dq_dqb.dqb_curspace) >
61			q->dq_dqb.dqb_bsoftlimit) {
62		if (!q->dq_dqb.dqb_btime)
63			q->dq_dqb.dqb_btime =
64				now + q->dq_h->qh_info.dqi_bgrace;
65	} else {
66		q->dq_dqb.dqb_btime = 0;
67	}
68
69	if (q->dq_dqb.dqb_isoftlimit && q->dq_dqb.dqb_curinodes >
70			q->dq_dqb.dqb_isoftlimit) {
71		if (!q->dq_dqb.dqb_itime)
72				q->dq_dqb.dqb_itime =
73					now + q->dq_h->qh_info.dqi_igrace;
74	} else {
75		q->dq_dqb.dqb_itime = 0;
76	}
77}
78
79static int release_blocks_proc(ext2_filsys fs, blk64_t *blocknr,
80			       e2_blkcnt_t blockcnt EXT2FS_ATTR((unused)),
81			       blk64_t ref_block EXT2FS_ATTR((unused)),
82			       int ref_offset EXT2FS_ATTR((unused)),
83			       void *private EXT2FS_ATTR((unused)))
84{
85	blk64_t	block;
86
87	block = *blocknr;
88	ext2fs_block_alloc_stats2(fs, block, -1);
89	return 0;
90}
91
92static int compute_num_blocks_proc(ext2_filsys fs, blk64_t *blocknr,
93			       e2_blkcnt_t blockcnt EXT2FS_ATTR((unused)),
94			       blk64_t ref_block EXT2FS_ATTR((unused)),
95			       int ref_offset EXT2FS_ATTR((unused)),
96			       void *private)
97{
98	blk64_t	block;
99	blk64_t *num_blocks = private;
100
101	*num_blocks += 1;
102	return 0;
103}
104
105void truncate_quota_inode(ext2_filsys fs, ext2_ino_t ino)
106{
107	struct ext2_inode inode;
108
109	if (ext2fs_read_inode(fs, ino, &inode))
110		return;
111
112	inode.i_dtime = fs->now ? fs->now : time(0);
113	if (!ext2fs_inode_has_valid_blocks(&inode))
114		return;
115
116	ext2fs_block_iterate3(fs, ino, BLOCK_FLAG_READ_ONLY, NULL,
117			      release_blocks_proc, NULL);
118
119	memset(&inode, 0, sizeof(struct ext2_inode));
120	ext2fs_write_inode(fs, ino, &inode);
121}
122
123static ext2_off64_t compute_inode_size(ext2_filsys fs, ext2_ino_t ino)
124{
125	blk64_t num_blocks = 0;
126
127	ext2fs_block_iterate3(fs, ino,
128			      BLOCK_FLAG_READ_ONLY,
129			      NULL,
130			      compute_num_blocks_proc,
131			      &num_blocks);
132	return num_blocks * fs->blocksize;
133}
134
135/* Functions to read/write quota file. */
136static unsigned int quota_write_nomount(struct quota_file *qf, loff_t offset,
137					void *buf, unsigned int size)
138{
139	ext2_file_t	e2_file = qf->e2_file;
140	unsigned int	bytes_written = 0;
141	errcode_t	err;
142
143	err = ext2fs_file_llseek(e2_file, offset, EXT2_SEEK_SET, NULL);
144	if (err) {
145		log_err("ext2fs_file_llseek failed: %ld", err);
146		return 0;
147	}
148
149	err = ext2fs_file_write(e2_file, buf, size, &bytes_written);
150	if (err) {
151		log_err("ext2fs_file_write failed: %ld", err);
152		return 0;
153	}
154
155	/* Correct inode.i_size is set in end_io. */
156	return bytes_written;
157}
158
159static unsigned int quota_read_nomount(struct quota_file *qf, loff_t offset,
160					void *buf, unsigned int size)
161{
162	ext2_file_t	e2_file = qf->e2_file;
163	unsigned int	bytes_read = 0;
164	errcode_t	err;
165
166	err = ext2fs_file_llseek(e2_file, offset, EXT2_SEEK_SET, NULL);
167	if (err) {
168		log_err("ext2fs_file_llseek failed: %ld", err);
169		return 0;
170	}
171
172	err = ext2fs_file_read(e2_file, buf, size, &bytes_read);
173	if (err) {
174		log_err("ext2fs_file_read failed: %ld", err);
175		return 0;
176	}
177
178	return bytes_read;
179}
180
181/*
182 * Detect quota format and initialize quota IO
183 */
184struct quota_handle *init_io(ext2_filsys fs, const char *mntpt, int type,
185			     int fmt, int flags)
186{
187	log_err("Not Implemented.", "");
188	BUG_ON(1);
189	return NULL;
190}
191
192static errcode_t init_new_quota_inode(ext2_filsys fs, ext2_ino_t ino)
193{
194	struct ext2_inode inode;
195	errcode_t err = 0;
196
197	err = ext2fs_read_inode(fs, ino, &inode);
198	if (err) {
199		log_err("ex2fs_read_inode failed", "");
200		return err;
201	}
202
203	if (EXT2_I_SIZE(&inode))
204		truncate_quota_inode(fs, ino);
205
206	memset(&inode, 0, sizeof(struct ext2_inode));
207	ext2fs_iblk_set(fs, &inode, 0);
208	inode.i_atime = inode.i_mtime =
209		inode.i_ctime = fs->now ? fs->now : time(0);
210	inode.i_links_count = 1;
211	inode.i_mode = LINUX_S_IFREG | 0600;
212	inode.i_flags |= EXT2_IMMUTABLE_FL;
213	if (fs->super->s_feature_incompat &
214			EXT3_FEATURE_INCOMPAT_EXTENTS)
215		inode.i_flags |= EXT4_EXTENTS_FL;
216
217	err = ext2fs_write_new_inode(fs, ino, &inode);
218	if (err) {
219		log_err("ext2fs_write_new_inode failed: %ld", err);
220		return err;
221	}
222	return err;
223}
224
225/*
226 * Create new quotafile of specified format on given filesystem
227 */
228int new_io(struct quota_handle *h, ext2_filsys fs, int type, int fmt)
229{
230	ext2_file_t e2_file;
231	int err;
232	unsigned long qf_inum;
233
234	if (fmt == -1)
235		fmt = QFMT_VFS_V1;
236
237	h->qh_qf.fs = fs;
238	if (type == USRQUOTA)
239		qf_inum = EXT4_USR_QUOTA_INO;
240	else if (type == GRPQUOTA)
241		qf_inum = EXT4_GRP_QUOTA_INO;
242	else
243		BUG_ON(1);
244	err = ext2fs_read_bitmaps(fs);
245	if (err)
246		goto out_err;
247
248	err = init_new_quota_inode(fs, qf_inum);
249	if (err) {
250		log_err("init_new_quota_inode failed", "");
251		goto out_err;
252	}
253	h->qh_qf.ino = qf_inum;
254	h->e2fs_write = quota_write_nomount;
255	h->e2fs_read = quota_read_nomount;
256
257	log_debug("Creating quota ino=%lu, type=%d", qf_inum, type);
258	err = ext2fs_file_open(fs, qf_inum,
259			EXT2_FILE_WRITE | EXT2_FILE_CREATE, &e2_file);
260	if (err) {
261		log_err("ext2fs_file_open failed: %d", err);
262		goto out_err;
263	}
264	h->qh_qf.e2_file = e2_file;
265
266	h->qh_io_flags = 0;
267	h->qh_type = type;
268	h->qh_fmt = fmt;
269	memset(&h->qh_info, 0, sizeof(h->qh_info));
270	h->qh_ops = &quotafile_ops_2;
271
272	if (h->qh_ops->new_io && (h->qh_ops->new_io(h) < 0)) {
273		log_err("qh_ops->new_io failed", "");
274		goto out_err1;
275	}
276
277	return 0;
278
279out_err1:
280	ext2fs_file_close(e2_file);
281out_err:
282
283	if (qf_inum)
284		truncate_quota_inode(fs, qf_inum);
285
286	return -1;
287}
288
289/*
290 * Close quotafile and release handle
291 */
292int end_io(struct quota_handle *h)
293{
294	if (h->qh_io_flags & IOFL_INFODIRTY) {
295		if (h->qh_ops->write_info && h->qh_ops->write_info(h) < 0)
296			return -1;
297		h->qh_io_flags &= ~IOFL_INFODIRTY;
298	}
299
300	if (h->qh_ops->end_io && h->qh_ops->end_io(h) < 0)
301		return -1;
302	if (h->qh_qf.e2_file) {
303		ext2fs_file_flush(h->qh_qf.e2_file);
304		ext2fs_file_set_size2(h->qh_qf.e2_file,
305			compute_inode_size(h->qh_qf.fs, h->qh_qf.ino));
306		ext2fs_file_close(h->qh_qf.e2_file);
307	}
308
309	return 0;
310}
311
312/*
313 * Create empty quota structure
314 */
315struct dquot *get_empty_dquot(void)
316{
317	struct dquot *dquot = smalloc(sizeof(struct dquot));
318
319	memset(dquot, 0, sizeof(*dquot));
320	dquot->dq_id = -1;
321	return dquot;
322}
323