Merge branch 'work.splice_read' of git://git.kernel.org/pub/scm/linux/kernel/git...
[cascardo/linux.git] / fs / xfs / xfs_qm_bhv.c
1 /*
2  * Copyright (c) 2000-2006 Silicon Graphics, Inc.
3  * All Rights Reserved.
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it would be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write the Free Software Foundation,
16  * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
17  */
18 #include "xfs.h"
19 #include "xfs_fs.h"
20 #include "xfs_format.h"
21 #include "xfs_log_format.h"
22 #include "xfs_trans_resv.h"
23 #include "xfs_quota.h"
24 #include "xfs_mount.h"
25 #include "xfs_inode.h"
26 #include "xfs_error.h"
27 #include "xfs_trans.h"
28 #include "xfs_qm.h"
29
30
31 STATIC void
32 xfs_fill_statvfs_from_dquot(
33         struct kstatfs          *statp,
34         struct xfs_dquot        *dqp)
35 {
36         __uint64_t              limit;
37
38         limit = dqp->q_core.d_blk_softlimit ?
39                 be64_to_cpu(dqp->q_core.d_blk_softlimit) :
40                 be64_to_cpu(dqp->q_core.d_blk_hardlimit);
41         if (limit && statp->f_blocks > limit) {
42                 statp->f_blocks = limit;
43                 statp->f_bfree = statp->f_bavail =
44                         (statp->f_blocks > dqp->q_res_bcount) ?
45                          (statp->f_blocks - dqp->q_res_bcount) : 0;
46         }
47
48         limit = dqp->q_core.d_ino_softlimit ?
49                 be64_to_cpu(dqp->q_core.d_ino_softlimit) :
50                 be64_to_cpu(dqp->q_core.d_ino_hardlimit);
51         if (limit && statp->f_files > limit) {
52                 statp->f_files = limit;
53                 statp->f_ffree =
54                         (statp->f_files > dqp->q_res_icount) ?
55                          (statp->f_ffree - dqp->q_res_icount) : 0;
56         }
57 }
58
59
60 /*
61  * Directory tree accounting is implemented using project quotas, where
62  * the project identifier is inherited from parent directories.
63  * A statvfs (df, etc.) of a directory that is using project quota should
64  * return a statvfs of the project, not the entire filesystem.
65  * This makes such trees appear as if they are filesystems in themselves.
66  */
67 void
68 xfs_qm_statvfs(
69         xfs_inode_t             *ip,
70         struct kstatfs          *statp)
71 {
72         xfs_mount_t             *mp = ip->i_mount;
73         xfs_dquot_t             *dqp;
74
75         if (!xfs_qm_dqget(mp, NULL, xfs_get_projid(ip), XFS_DQ_PROJ, 0, &dqp)) {
76                 xfs_fill_statvfs_from_dquot(statp, dqp);
77                 xfs_qm_dqput(dqp);
78         }
79 }
80
81 int
82 xfs_qm_newmount(
83         xfs_mount_t     *mp,
84         uint            *needquotamount,
85         uint            *quotaflags)
86 {
87         uint            quotaondisk;
88         uint            uquotaondisk = 0, gquotaondisk = 0, pquotaondisk = 0;
89
90         quotaondisk = xfs_sb_version_hasquota(&mp->m_sb) &&
91                                 (mp->m_sb.sb_qflags & XFS_ALL_QUOTA_ACCT);
92
93         if (quotaondisk) {
94                 uquotaondisk = mp->m_sb.sb_qflags & XFS_UQUOTA_ACCT;
95                 pquotaondisk = mp->m_sb.sb_qflags & XFS_PQUOTA_ACCT;
96                 gquotaondisk = mp->m_sb.sb_qflags & XFS_GQUOTA_ACCT;
97         }
98
99         /*
100          * If the device itself is read-only, we can't allow
101          * the user to change the state of quota on the mount -
102          * this would generate a transaction on the ro device,
103          * which would lead to an I/O error and shutdown
104          */
105
106         if (((uquotaondisk && !XFS_IS_UQUOTA_ON(mp)) ||
107             (!uquotaondisk &&  XFS_IS_UQUOTA_ON(mp)) ||
108              (gquotaondisk && !XFS_IS_GQUOTA_ON(mp)) ||
109             (!gquotaondisk &&  XFS_IS_GQUOTA_ON(mp)) ||
110              (pquotaondisk && !XFS_IS_PQUOTA_ON(mp)) ||
111             (!pquotaondisk &&  XFS_IS_PQUOTA_ON(mp)))  &&
112             xfs_dev_is_read_only(mp, "changing quota state")) {
113                 xfs_warn(mp, "please mount with%s%s%s%s.",
114                         (!quotaondisk ? "out quota" : ""),
115                         (uquotaondisk ? " usrquota" : ""),
116                         (gquotaondisk ? " grpquota" : ""),
117                         (pquotaondisk ? " prjquota" : ""));
118                 return -EPERM;
119         }
120
121         if (XFS_IS_QUOTA_ON(mp) || quotaondisk) {
122                 /*
123                  * Call mount_quotas at this point only if we won't have to do
124                  * a quotacheck.
125                  */
126                 if (quotaondisk && !XFS_QM_NEED_QUOTACHECK(mp)) {
127                         /*
128                          * If an error occurred, qm_mount_quotas code
129                          * has already disabled quotas. So, just finish
130                          * mounting, and get on with the boring life
131                          * without disk quotas.
132                          */
133                         xfs_qm_mount_quotas(mp);
134                 } else {
135                         /*
136                          * Clear the quota flags, but remember them. This
137                          * is so that the quota code doesn't get invoked
138                          * before we're ready. This can happen when an
139                          * inode goes inactive and wants to free blocks,
140                          * or via xfs_log_mount_finish.
141                          */
142                         *needquotamount = true;
143                         *quotaflags = mp->m_qflags;
144                         mp->m_qflags = 0;
145                 }
146         }
147
148         return 0;
149 }