vserver 1.9.5.x5

[linux-2.6.git] / fs / quota.c

diff --git a/fs/quota.c b/fs/quota.c
index 3dd9be6..83cd513 100644 (file)
--- a/fs/quota.c
+++ b/fs/quota.c
@@ -13,6 +13,10 @@
 #include <linux/kernel.h>
 #include <linux/smp_lock.h>
 #include <linux/security.h>
+#include <linux/syscalls.h>
+#include <linux/buffer_head.h>
+#include <linux/major.h>
+#include <linux/blkdev.h>
 
 /* Check validity of quotactl */
 static int check_quotactl_valid(struct super_block *sb, int type, int cmd, qid_t id)
@@ -94,11 +98,11 @@ static int check_quotactl_valid(struct super_block *sb, int type, int cmd, qid_t
        if (cmd == Q_GETQUOTA || cmd == Q_XGETQUOTA) {
                if (((type == USRQUOTA && current->euid != id) ||
                     (type == GRPQUOTA && !in_egroup_p(id))) &&
-                   !capable(CAP_SYS_ADMIN))
+                   !capable(CAP_SYS_ADMIN) && !vx_ccaps(VXC_QUOTA_CTL))
                        return -EPERM;
        }
        else if (cmd != Q_GETFMT && cmd != Q_SYNC && cmd != Q_GETINFO && cmd != Q_XGETQSTAT)
-               if (!capable(CAP_SYS_ADMIN))
+               if (!capable(CAP_SYS_ADMIN) && !vx_ccaps(VXC_QUOTA_CTL))
                        return -EPERM;
 
        return security_quotactl (cmd, type, id, sb);
@@ -134,16 +138,54 @@ restart:
        return NULL;
 }
 
+static void quota_sync_sb(struct super_block *sb, int type)
+{
+       int cnt;
+       struct inode *discard[MAXQUOTAS];
+
+       sb->s_qcop->quota_sync(sb, type);
+       /* This is not very clever (and fast) but currently I don't know about
+        * any other simple way of getting quota data to disk and we must get
+        * them there for userspace to be visible... */
+       if (sb->s_op->sync_fs)
+               sb->s_op->sync_fs(sb, 1);
+       sync_blockdev(sb->s_bdev);
+
+       /* Now when everything is written we can discard the pagecache so
+        * that userspace sees the changes. We need i_sem and so we could
+        * not do it inside dqonoff_sem. Moreover we need to be carefull
+        * about races with quotaoff() (that is the reason why we have own
+        * reference to inode). */
+       down(&sb_dqopt(sb)->dqonoff_sem);
+       for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+               discard[cnt] = NULL;
+               if (type != -1 && cnt != type)
+                       continue;
+               if (!sb_has_quota_enabled(sb, cnt))
+                       continue;
+               discard[cnt] = igrab(sb_dqopt(sb)->files[cnt]);
+       }
+       up(&sb_dqopt(sb)->dqonoff_sem);
+       for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
+               if (discard[cnt]) {
+                       down(&discard[cnt]->i_sem);
+                       truncate_inode_pages(&discard[cnt]->i_data, 0);
+                       up(&discard[cnt]->i_sem);
+                       iput(discard[cnt]);
+               }
+       }
+}
+
 void sync_dquots(struct super_block *sb, int type)
 {
        if (sb) {
                if (sb->s_qcop->quota_sync)
-                       sb->s_qcop->quota_sync(sb, type);
+                       quota_sync_sb(sb, type);
        }
        else {
-               while ((sb = get_super_to_sync(type)) != 0) {
+               while ((sb = get_super_to_sync(type)) != NULL) {
                        if (sb->s_qcop->quota_sync)
-                               sb->s_qcop->quota_sync(sb, type);
+                               quota_sync_sb(sb, type);
                        drop_super(sb);
                }
        }
@@ -258,6 +300,10 @@ static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id, void
        return 0;
 }
 
+#ifdef CONFIG_BLK_DEV_VROOT
+extern struct block_device *vroot_get_real_bdev(struct block_device *);
+#endif
+
 /*
  * This is the system call interface. This communicates with
  * the user-level programs. Currently this only supports diskquota
@@ -283,6 +329,22 @@ asmlinkage long sys_quotactl(unsigned int cmd, const char __user *special, qid_t
                putname(tmp);
                if (IS_ERR(bdev))
                        return PTR_ERR(bdev);
+#ifdef CONFIG_BLK_DEV_VROOT
+               printk(KERN_INFO "bdev=%p, gendisk=%p inode=%p[%d,%d]\n",
+                       bdev, bdev?bdev->bd_disk:0, bdev->bd_inode,
+                       imajor(bdev->bd_inode), iminor(bdev->bd_inode));
+
+               if (bdev && bdev->bd_inode &&
+                       imajor(bdev->bd_inode) == VROOT_MAJOR) {
+                       struct block_device *bdnew =
+                               vroot_get_real_bdev(bdev);
+
+                       bdput(bdev);
+                       if (IS_ERR(bdnew))
+                               return PTR_ERR(bdnew);
+                       bdev = bdnew;
+               }
+#endif
                sb = get_super(bdev);
                bdput(bdev);
                if (!sb)