#include <linux/module.h>
#include <linux/slab.h>
-#include <linux/init.h>
-#include <linux/smp_lock.h>
#include <linux/acct.h>
#include <linux/blkdev.h>
-#include <linux/quotaops.h>
-#include <linux/namei.h>
#include <linux/mount.h>
#include <linux/security.h>
-#include <linux/syscalls.h>
#include <linux/writeback.h> /* for the emergency remount stuff */
#include <linux/idr.h>
-#include <linux/kobject.h>
#include <linux/mutex.h>
-#include <linux/file.h>
#include <linux/backing-dev.h>
-#include <asm/uaccess.h>
#include "internal.h"
s->s_count = 1;
atomic_set(&s->s_active, 1);
mutex_init(&s->s_vfs_rename_mutex);
+ lockdep_set_class(&s->s_vfs_rename_mutex, &type->s_vfs_rename_key);
mutex_init(&s->s_dquot.dqio_mutex);
mutex_init(&s->s_dquot.dqonoff_mutex);
init_rwsem(&s->s_dquot.dqptr_sem);
init_waitqueue_head(&s->s_wait_unfrozen);
s->s_maxbytes = MAX_NON_LFS;
- s->dq_op = sb_dquot_ops;
- s->s_qcop = sb_quotactl_ops;
s->s_op = &default_op;
s->s_time_gran = 1000000000;
}
{
struct file_system_type *fs = s->s_type;
if (atomic_dec_and_test(&s->s_active)) {
- vfs_dq_off(s, 0);
fs->kill_sb(s);
put_filesystem(fs);
put_super(s);
int do_remount_sb(struct super_block *sb, int flags, void *data, int force)
{
int retval;
- int remount_rw, remount_ro;
+ int remount_ro;
if (sb->s_frozen != SB_UNFROZEN)
return -EBUSY;
sync_filesystem(sb);
remount_ro = (flags & MS_RDONLY) && !(sb->s_flags & MS_RDONLY);
- remount_rw = !(flags & MS_RDONLY) && (sb->s_flags & MS_RDONLY);
/* If we are remounting RDONLY and current sb is read/write,
make sure there are no rw files opened */
mark_files_ro(sb);
else if (!fs_may_remount_ro(sb))
return -EBUSY;
- retval = vfs_dq_off(sb, 1);
- if (retval < 0 && retval != -ENOSYS)
- return -EBUSY;
}
if (sb->s_op->remount_fs) {
return retval;
}
sb->s_flags = (sb->s_flags & ~MS_RMT_MASK) | (flags & MS_RMT_MASK);
- if (remount_rw)
- vfs_dq_quota_on_remount(sb);
+
/*
* Some filesystems modify their metadata via some other path than the
* bdev buffer cache (eg. use a private mapping, or directories in
EXPORT_SYMBOL_GPL(vfs_kern_mount);
+/**
+ * freeze_super - lock the filesystem and force it into a consistent state
+ * @sb: the super to lock
+ *
+ * Syncs the super to make sure the filesystem is consistent and calls the fs's
+ * freeze_fs. Subsequent calls to this without first thawing the fs will return
+ * -EBUSY.
+ */
+int freeze_super(struct super_block *sb)
+{
+ int ret;
+
+ atomic_inc(&sb->s_active);
+ down_write(&sb->s_umount);
+ if (sb->s_frozen) {
+ deactivate_locked_super(sb);
+ return -EBUSY;
+ }
+
+ if (sb->s_flags & MS_RDONLY) {
+ sb->s_frozen = SB_FREEZE_TRANS;
+ smp_wmb();
+ up_write(&sb->s_umount);
+ return 0;
+ }
+
+ sb->s_frozen = SB_FREEZE_WRITE;
+ smp_wmb();
+
+ sync_filesystem(sb);
+
+ sb->s_frozen = SB_FREEZE_TRANS;
+ smp_wmb();
+
+ sync_blockdev(sb->s_bdev);
+ if (sb->s_op->freeze_fs) {
+ ret = sb->s_op->freeze_fs(sb);
+ if (ret) {
+ printk(KERN_ERR
+ "VFS:Filesystem freeze failed\n");
+ sb->s_frozen = SB_UNFROZEN;
+ deactivate_locked_super(sb);
+ return ret;
+ }
+ }
+ up_write(&sb->s_umount);
+ return 0;
+}
+EXPORT_SYMBOL(freeze_super);
+
+/**
+ * thaw_super -- unlock filesystem
+ * @sb: the super to thaw
+ *
+ * Unlocks the filesystem and marks it writeable again after freeze_super().
+ */
+int thaw_super(struct super_block *sb)
+{
+ int error;
+
+ down_write(&sb->s_umount);
+ if (sb->s_frozen == SB_UNFROZEN) {
+ up_write(&sb->s_umount);
+ return -EINVAL;
+ }
+
+ if (sb->s_flags & MS_RDONLY)
+ goto out;
+
+ if (sb->s_op->unfreeze_fs) {
+ error = sb->s_op->unfreeze_fs(sb);
+ if (error) {
+ printk(KERN_ERR
+ "VFS:Filesystem thaw failed\n");
+ sb->s_frozen = SB_FREEZE_TRANS;
+ up_write(&sb->s_umount);
+ return error;
+ }
+ }
+
+out:
+ sb->s_frozen = SB_UNFROZEN;
+ smp_wmb();
+ wake_up(&sb->s_wait_unfrozen);
+ deactivate_locked_super(sb);
+
+ return 0;
+}
+EXPORT_SYMBOL(thaw_super);
+
static struct vfsmount *fs_set_subtype(struct vfsmount *mnt, const char *fstype)
{
int err;