aboutsummaryrefslogtreecommitdiff
path: root/fs/quota/kqid.c
blob: 2f97b0e2c501d37ab45d600ec0870bd4985f5546 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
#include <linux/fs.h>
#include <linux/quota.h>
#include <linux/export.h>

/**
 *	qid_eq - Test to see if to kquid values are the same
 *	@left: A qid value
 *	@right: Another quid value
 *
 *	Return true if the two qid values are equal and false otherwise.
 */
bool qid_eq(struct kqid left, struct kqid right)
{
	if (left.type != right.type)
		return false;
	switch(left.type) {
	case USRQUOTA:
		return uid_eq(left.uid, right.uid);
	case GRPQUOTA:
		return gid_eq(left.gid, right.gid);
	case PRJQUOTA:
		return projid_eq(left.projid, right.projid);
	default:
		BUG();
	}
}
EXPORT_SYMBOL(qid_eq);

/**
 *	qid_lt - Test to see if one qid value is less than another
 *	@left: The possibly lesser qid value
 *	@right: The possibly greater qid value
 *
 *	Return true if left is less than right and false otherwise.
 */
bool qid_lt(struct kqid left, struct kqid right)
{
	if (left.type < right.type)
		return true;
	if (left.type > right.type)
		return false;
	switch (left.type) {
	case USRQUOTA:
		return uid_lt(left.uid, right.uid);
	case GRPQUOTA:
		return gid_lt(left.gid, right.gid);
	case PRJQUOTA:
		return projid_lt(left.projid, right.projid);
	default:
		BUG();
	}
}
EXPORT_SYMBOL(qid_lt);

/**
 *	from_kqid - Create a qid from a kqid user-namespace pair.
 *	@targ: The user namespace we want a qid in.
 *	@kuid: The kernel internal quota identifier to start with.
 *
 *	Map @kqid into the user-namespace specified by @targ and
 *	return the resulting qid.
 *
 *	There is always a mapping into the initial user_namespace.
 *
 *	If @kqid has no mapping in @targ (qid_t)-1 is returned.
 */
qid_t from_kqid(struct user_namespace *targ, struct kqid kqid)
{
	switch (kqid.type) {
	case USRQUOTA:
		return from_kuid(targ, kqid.uid);
	case GRPQUOTA:
		return from_kgid(targ, kqid.gid);
	case PRJQUOTA:
		return from_kprojid(targ, kqid.projid);
	default:
		BUG();
	}
}
EXPORT_SYMBOL(from_kqid);

/**
 *	from_kqid_munged - Create a qid from a kqid user-namespace pair.
 *	@targ: The user namespace we want a qid in.
 *	@kqid: The kernel internal quota identifier to start with.
 *
 *	Map @kqid into the user-namespace specified by @targ and
 *	return the resulting qid.
 *
 *	There is always a mapping into the initial user_namespace.
 *
 *	Unlike from_kqid from_kqid_munged never fails and always
 *	returns a valid projid.  This makes from_kqid_munged
 *	appropriate for use in places where failing to provide
 *	a qid_t is not a good option.
 *
 *	If @kqid has no mapping in @targ the kqid.type specific
 *	overflow identifier is returned.
 */
qid_t from_kqid_munged(struct user_namespace *targ, struct kqid kqid)
{
	switch (kqid.type) {
	case USRQUOTA:
		return from_kuid_munged(targ, kqid.uid);
	case GRPQUOTA:
		return from_kgid_munged(targ, kqid.gid);
	case PRJQUOTA:
		return from_kprojid_munged(targ, kqid.projid);
	default:
		BUG();
	}
}
EXPORT_SYMBOL(from_kqid_munged);

/**
 *	qid_valid - Report if a valid value is stored in a kqid.
 *	@qid: The kernel internal quota identifier to test.
 */
bool qid_valid(struct kqid qid)
{
	switch (qid.type) {
	case USRQUOTA:
		return uid_valid(qid.uid);
	case GRPQUOTA:
		return gid_valid(qid.gid);
	case PRJQUOTA:
		return projid_valid(qid.projid);
	default:
		BUG();
	}
}
EXPORT_SYMBOL(qid_valid);