42 static int thaw_super_locked(struct super_block *sb);
63 	struct super_block *sb;  in super_cache_scan()  local
70 	sb = container_of(shrink, struct super_block, s_shrink);  in super_cache_scan()
79 	if (!trylock_super(sb))  in super_cache_scan()
82 	if (sb->s_op->nr_cached_objects)  in super_cache_scan()
83 		fs_objects = sb->s_op->nr_cached_objects(sb, sc);  in super_cache_scan()
85 	inodes = list_lru_shrink_count(&sb->s_inode_lru, sc);  in super_cache_scan()
86 	dentries = list_lru_shrink_count(&sb->s_dentry_lru, sc);  in super_cache_scan()
104 	freed = prune_dcache_sb(sb, sc);  in super_cache_scan()
106 	freed += prune_icache_sb(sb, sc);  in super_cache_scan()
110 		freed += sb->s_op->free_cached_objects(sb, sc);  in super_cache_scan()
113 	up_read(&sb->s_umount);  in super_cache_scan()
120 	struct super_block *sb;  in super_cache_count()  local
123 	sb = container_of(shrink, struct super_block, s_shrink);  in super_cache_count()
139 	if (!(sb->s_flags & SB_BORN))  in super_cache_count()
143 	if (sb->s_op && sb->s_op->nr_cached_objects)  in super_cache_count()
144 		total_objects = sb->s_op->nr_cached_objects(sb, sc);  in super_cache_count()
146 	total_objects += list_lru_shrink_count(&sb->s_dentry_lru, sc);  in super_cache_count()
147 	total_objects += list_lru_shrink_count(&sb->s_inode_lru, sc);  in super_cache_count()
308 void put_super(struct super_block *sb)  in put_super()  argument
311 	__put_super(sb);  in put_super()
413 bool trylock_super(struct super_block *sb)  in trylock_super()  argument
415 	if (down_read_trylock(&sb->s_umount)) {  in trylock_super()
416 		if (!hlist_unhashed(&sb->s_instances) &&  in trylock_super()
417 		    sb->s_root && (sb->s_flags & SB_BORN))  in trylock_super()
419 		up_read(&sb->s_umount);  in trylock_super()
441 void retire_super(struct super_block *sb)  in retire_super()  argument
443 	WARN_ON(!sb->s_bdev);  in retire_super()
444 	down_write(&sb->s_umount);  in retire_super()
445 	if (sb->s_iflags & SB_I_PERSB_BDI) {  in retire_super()
446 		bdi_unregister(sb->s_bdi);  in retire_super()
447 		sb->s_iflags &= ~SB_I_PERSB_BDI;  in retire_super()
449 	sb->s_iflags |= SB_I_RETIRED;  in retire_super()
450 	up_write(&sb->s_umount);  in retire_super()
468 void generic_shutdown_super(struct super_block *sb)  in generic_shutdown_super()  argument
470 	const struct super_operations *sop = sb->s_op;  in generic_shutdown_super()
472 	if (sb->s_root) {  in generic_shutdown_super()
473 		shrink_dcache_for_umount(sb);  in generic_shutdown_super()
474 		sync_filesystem(sb);  in generic_shutdown_super()
475 		sb->s_flags &= ~SB_ACTIVE;  in generic_shutdown_super()
480 		evict_inodes(sb);  in generic_shutdown_super()
482 		fsnotify_sb_delete(sb);  in generic_shutdown_super()
483 		fscrypt_destroy_keyring(sb);  in generic_shutdown_super()
484 		security_sb_delete(sb);  in generic_shutdown_super()
486 		if (sb->s_dio_done_wq) {  in generic_shutdown_super()
487 			destroy_workqueue(sb->s_dio_done_wq);  in generic_shutdown_super()
488 			sb->s_dio_done_wq = NULL;  in generic_shutdown_super()
492 			sop->put_super(sb);  in generic_shutdown_super()
494 		if (!list_empty(&sb->s_inodes)) {  in generic_shutdown_super()
497 			   sb->s_id);  in generic_shutdown_super()
502 	hlist_del_init(&sb->s_instances);  in generic_shutdown_super()
504 	up_write(&sb->s_umount);  in generic_shutdown_super()
505 	if (sb->s_bdi != &noop_backing_dev_info) {  in generic_shutdown_super()
506 		if (sb->s_iflags & SB_I_PERSB_BDI)  in generic_shutdown_super()
507 			bdi_unregister(sb->s_bdi);  in generic_shutdown_super()
508 		bdi_put(sb->s_bdi);  in generic_shutdown_super()
509 		sb->s_bdi = &noop_backing_dev_info;  in generic_shutdown_super()
666 void drop_super(struct super_block *sb)  in drop_super()  argument
668 	up_read(&sb->s_umount);  in drop_super()
669 	put_super(sb);  in drop_super()
674 void drop_super_exclusive(struct super_block *sb)  in drop_super_exclusive()  argument
676 	up_write(&sb->s_umount);  in drop_super_exclusive()
677 	put_super(sb);  in drop_super_exclusive()
683 	struct super_block *sb, *p = NULL;  in __iterate_supers()  local
686 	list_for_each_entry(sb, &super_blocks, s_list) {  in __iterate_supers()
687 		if (hlist_unhashed(&sb->s_instances))  in __iterate_supers()
689 		sb->s_count++;  in __iterate_supers()
692 		f(sb);  in __iterate_supers()
697 		p = sb;  in __iterate_supers()
713 	struct super_block *sb, *p = NULL;  in iterate_supers()  local
716 	list_for_each_entry(sb, &super_blocks, s_list) {  in iterate_supers()
717 		if (hlist_unhashed(&sb->s_instances))  in iterate_supers()
719 		sb->s_count++;  in iterate_supers()
722 		down_read(&sb->s_umount);  in iterate_supers()
723 		if (sb->s_root && (sb->s_flags & SB_BORN))  in iterate_supers()
724 			f(sb, arg);  in iterate_supers()
725 		up_read(&sb->s_umount);  in iterate_supers()
730 		p = sb;  in iterate_supers()
749 	struct super_block *sb, *p = NULL;  in iterate_supers_type()  local
752 	hlist_for_each_entry(sb, &type->fs_supers, s_instances) {  in iterate_supers_type()
753 		sb->s_count++;  in iterate_supers_type()
756 		down_read(&sb->s_umount);  in iterate_supers_type()
757 		if (sb->s_root && (sb->s_flags & SB_BORN))  in iterate_supers_type()
758 			f(sb, arg);  in iterate_supers_type()
759 		up_read(&sb->s_umount);  in iterate_supers_type()
764 		p = sb;  in iterate_supers_type()
782 	struct super_block *sb;  in get_super()  local
789 	list_for_each_entry(sb, &super_blocks, s_list) {  in get_super()
790 		if (hlist_unhashed(&sb->s_instances))  in get_super()
792 		if (sb->s_bdev == bdev) {  in get_super()
793 			sb->s_count++;  in get_super()
795 			down_read(&sb->s_umount);  in get_super()
797 			if (sb->s_root && (sb->s_flags & SB_BORN))  in get_super()
798 				return sb;  in get_super()
799 			up_read(&sb->s_umount);  in get_super()
802 			__put_super(sb);  in get_super()
820 	struct super_block *sb;  in get_active_super()  local
827 	list_for_each_entry(sb, &super_blocks, s_list) {  in get_active_super()
828 		if (hlist_unhashed(&sb->s_instances))  in get_active_super()
830 		if (sb->s_bdev == bdev) {  in get_active_super()
831 			if (!grab_super(sb))  in get_active_super()
833 			up_write(&sb->s_umount);  in get_active_super()
834 			return sb;  in get_active_super()
843 	struct super_block *sb;  in user_get_super()  local
847 	list_for_each_entry(sb, &super_blocks, s_list) {  in user_get_super()
848 		if (hlist_unhashed(&sb->s_instances))  in user_get_super()
850 		if (sb->s_dev ==  dev) {  in user_get_super()
851 			sb->s_count++;  in user_get_super()
854 				down_write(&sb->s_umount);  in user_get_super()
856 				down_read(&sb->s_umount);  in user_get_super()
858 			if (sb->s_root && (sb->s_flags & SB_BORN))  in user_get_super()
859 				return sb;  in user_get_super()
861 				up_write(&sb->s_umount);  in user_get_super()
863 				up_read(&sb->s_umount);  in user_get_super()
866 			__put_super(sb);  in user_get_super()
882 	struct super_block *sb = fc->root->d_sb;  in reconfigure_super()  local
889 	if (sb->s_writers.frozen != SB_UNFROZEN)  in reconfigure_super()
892 	retval = security_sb_remount(sb, fc->security);  in reconfigure_super()
898 		if (!(fc->sb_flags & SB_RDONLY) && sb->s_bdev &&  in reconfigure_super()
899 		    bdev_read_only(sb->s_bdev))  in reconfigure_super()
903 		remount_ro = (fc->sb_flags & SB_RDONLY) && !sb_rdonly(sb);  in reconfigure_super()
907 		if (!hlist_empty(&sb->s_pins)) {  in reconfigure_super()
908 			up_write(&sb->s_umount);  in reconfigure_super()
909 			group_pin_kill(&sb->s_pins);  in reconfigure_super()
910 			down_write(&sb->s_umount);  in reconfigure_super()
911 			if (!sb->s_root)  in reconfigure_super()
913 			if (sb->s_writers.frozen != SB_UNFROZEN)  in reconfigure_super()
915 			remount_ro = !sb_rdonly(sb);  in reconfigure_super()
918 	shrink_dcache_sb(sb);  in reconfigure_super()
925 			sb->s_readonly_remount = 1;  in reconfigure_super()
928 			retval = sb_prepare_remount_readonly(sb);  in reconfigure_super()
941 			     sb->s_type->name, retval);  in reconfigure_super()
945 	WRITE_ONCE(sb->s_flags, ((sb->s_flags & ~fc->sb_flags_mask) |  in reconfigure_super()
949 	sb->s_readonly_remount = 0;  in reconfigure_super()
959 	if (remount_ro && sb->s_bdev)  in reconfigure_super()
960 		invalidate_bdev(sb->s_bdev);  in reconfigure_super()
964 	sb->s_readonly_remount = 0;  in reconfigure_super()
968 static void do_emergency_remount_callback(struct super_block *sb)  in do_emergency_remount_callback()  argument
970 	down_write(&sb->s_umount);  in do_emergency_remount_callback()
971 	if (sb->s_root && sb->s_bdev && (sb->s_flags & SB_BORN) &&  in do_emergency_remount_callback()
972 	    !sb_rdonly(sb)) {  in do_emergency_remount_callback()
975 		fc = fs_context_for_reconfigure(sb->s_root,  in do_emergency_remount_callback()
983 	up_write(&sb->s_umount);  in do_emergency_remount_callback()
1004 static void do_thaw_all_callback(struct super_block *sb)  in do_thaw_all_callback()  argument
1006 	down_write(&sb->s_umount);  in do_thaw_all_callback()
1007 	if (sb->s_root && sb->s_flags & SB_BORN) {  in do_thaw_all_callback()
1008 		emergency_thaw_bdev(sb);  in do_thaw_all_callback()
1009 		thaw_super_locked(sb);  in do_thaw_all_callback()
1011 		up_write(&sb->s_umount);  in do_thaw_all_callback()
1083 void kill_anon_super(struct super_block *sb)  in kill_anon_super()  argument
1085 	dev_t dev = sb->s_dev;  in kill_anon_super()
1086 	generic_shutdown_super(sb);  in kill_anon_super()
1091 void kill_litter_super(struct super_block *sb)  in kill_litter_super()  argument
1093 	if (sb->s_root)  in kill_litter_super()
1094 		d_genocide(sb->s_root);  in kill_litter_super()
1095 	kill_anon_super(sb);  in kill_litter_super()
1099 int set_anon_super_fc(struct super_block *sb, struct fs_context *fc)  in set_anon_super_fc()  argument
1101 	return set_anon_super(sb, NULL);  in set_anon_super_fc()
1105 static int test_keyed_super(struct super_block *sb, struct fs_context *fc)  in test_keyed_super()  argument
1107 	return sb->s_fs_info == fc->s_fs_info;  in test_keyed_super()
1142 		  int (*fill_super)(struct super_block *sb,  in vfs_get_super()  argument
1146 	struct super_block *sb;  in vfs_get_super()  local
1164 	sb = sget_fc(fc, test, set_anon_super_fc);  in vfs_get_super()
1165 	if (IS_ERR(sb))  in vfs_get_super()
1166 		return PTR_ERR(sb);  in vfs_get_super()
1168 	if (!sb->s_root) {  in vfs_get_super()
1169 		err = fill_super(sb, fc);  in vfs_get_super()
1173 		sb->s_flags |= SB_ACTIVE;  in vfs_get_super()
1174 		fc->root = dget(sb->s_root);  in vfs_get_super()
1176 		fc->root = dget(sb->s_root);  in vfs_get_super()
1190 	deactivate_locked_super(sb);  in vfs_get_super()
1196 		  int (*fill_super)(struct super_block *sb,  in get_tree_nodev()  argument
1204 		  int (*fill_super)(struct super_block *sb,  in get_tree_single()  argument
1212 		  int (*fill_super)(struct super_block *sb,  in get_tree_single_reconf()  argument
1220 		  int (*fill_super)(struct super_block *sb,  in get_tree_keyed()  argument
1422 void kill_block_super(struct super_block *sb)  in kill_block_super()  argument
1424 	struct block_device *bdev = sb->s_bdev;  in kill_block_super()
1425 	fmode_t mode = sb->s_mode;  in kill_block_super()
1428 	generic_shutdown_super(sb);  in kill_block_super()
1522 	struct super_block *sb;  in vfs_get_tree()  local
1544 	sb = fc->root->d_sb;  in vfs_get_tree()
1545 	WARN_ON(!sb->s_bdi);  in vfs_get_tree()
1554 	sb->s_flags |= SB_BORN;  in vfs_get_tree()
1556 	error = security_sb_set_mnt_opts(sb, fc->security, 0, NULL);  in vfs_get_tree()
1568 	WARN((sb->s_maxbytes < 0), "%s set sb->s_maxbytes to "  in vfs_get_tree()
1569 		"negative value (%lld)\n", fc->fs_type->name, sb->s_maxbytes);  in vfs_get_tree()
1579 int super_setup_bdi_name(struct super_block *sb, char *fmt, ...)  in super_setup_bdi_name()  argument
1596 	WARN_ON(sb->s_bdi != &noop_backing_dev_info);  in super_setup_bdi_name()
1597 	sb->s_bdi = bdi;  in super_setup_bdi_name()
1598 	sb->s_iflags |= SB_I_PERSB_BDI;  in super_setup_bdi_name()
1608 int super_setup_bdi(struct super_block *sb)  in super_setup_bdi()  argument
1612 	return super_setup_bdi_name(sb, "%.28s-%ld", sb->s_type->name,  in super_setup_bdi()
1625 static void sb_wait_write(struct super_block *sb, int level)  in sb_wait_write()  argument
1627 	percpu_down_write(sb->s_writers.rw_sem + level-1);  in sb_wait_write()
1634 static void lockdep_sb_freeze_release(struct super_block *sb)  in lockdep_sb_freeze_release()  argument
1639 		percpu_rwsem_release(sb->s_writers.rw_sem + level, 0, _THIS_IP_);  in lockdep_sb_freeze_release()
1645 static void lockdep_sb_freeze_acquire(struct super_block *sb)  in lockdep_sb_freeze_acquire()  argument
1650 		percpu_rwsem_acquire(sb->s_writers.rw_sem + level, 0, _THIS_IP_);  in lockdep_sb_freeze_acquire()
1653 static void sb_freeze_unlock(struct super_block *sb, int level)  in sb_freeze_unlock()  argument
1656 		percpu_up_write(sb->s_writers.rw_sem + level);  in sb_freeze_unlock()
1692 int freeze_super(struct super_block *sb)  in freeze_super()  argument
1696 	atomic_inc(&sb->s_active);  in freeze_super()
1697 	down_write(&sb->s_umount);  in freeze_super()
1698 	if (sb->s_writers.frozen != SB_UNFROZEN) {  in freeze_super()
1699 		deactivate_locked_super(sb);  in freeze_super()
1703 	if (!(sb->s_flags & SB_BORN)) {  in freeze_super()
1704 		up_write(&sb->s_umount);  in freeze_super()
1708 	if (sb_rdonly(sb)) {  in freeze_super()
1710 		sb->s_writers.frozen = SB_FREEZE_COMPLETE;  in freeze_super()
1711 		up_write(&sb->s_umount);  in freeze_super()
1715 	sb->s_writers.frozen = SB_FREEZE_WRITE;  in freeze_super()
1717 	up_write(&sb->s_umount);  in freeze_super()
1718 	sb_wait_write(sb, SB_FREEZE_WRITE);  in freeze_super()
1719 	down_write(&sb->s_umount);  in freeze_super()
1722 	sb->s_writers.frozen = SB_FREEZE_PAGEFAULT;  in freeze_super()
1723 	sb_wait_write(sb, SB_FREEZE_PAGEFAULT);  in freeze_super()
1726 	ret = sync_filesystem(sb);  in freeze_super()
1728 		sb->s_writers.frozen = SB_UNFROZEN;  in freeze_super()
1729 		sb_freeze_unlock(sb, SB_FREEZE_PAGEFAULT);  in freeze_super()
1730 		wake_up(&sb->s_writers.wait_unfrozen);  in freeze_super()
1731 		deactivate_locked_super(sb);  in freeze_super()
1736 	sb->s_writers.frozen = SB_FREEZE_FS;  in freeze_super()
1737 	sb_wait_write(sb, SB_FREEZE_FS);  in freeze_super()
1739 	if (sb->s_op->freeze_fs) {  in freeze_super()
1740 		ret = sb->s_op->freeze_fs(sb);  in freeze_super()
1744 			sb->s_writers.frozen = SB_UNFROZEN;  in freeze_super()
1745 			sb_freeze_unlock(sb, SB_FREEZE_FS);  in freeze_super()
1746 			wake_up(&sb->s_writers.wait_unfrozen);  in freeze_super()
1747 			deactivate_locked_super(sb);  in freeze_super()
1755 	sb->s_writers.frozen = SB_FREEZE_COMPLETE;  in freeze_super()
1756 	lockdep_sb_freeze_release(sb);  in freeze_super()
1757 	up_write(&sb->s_umount);  in freeze_super()
1762 static int thaw_super_locked(struct super_block *sb)  in thaw_super_locked()  argument
1766 	if (sb->s_writers.frozen != SB_FREEZE_COMPLETE) {  in thaw_super_locked()
1767 		up_write(&sb->s_umount);  in thaw_super_locked()
1771 	if (sb_rdonly(sb)) {  in thaw_super_locked()
1772 		sb->s_writers.frozen = SB_UNFROZEN;  in thaw_super_locked()
1776 	lockdep_sb_freeze_acquire(sb);  in thaw_super_locked()
1778 	if (sb->s_op->unfreeze_fs) {  in thaw_super_locked()
1779 		error = sb->s_op->unfreeze_fs(sb);  in thaw_super_locked()
1783 			lockdep_sb_freeze_release(sb);  in thaw_super_locked()
1784 			up_write(&sb->s_umount);  in thaw_super_locked()
1789 	sb->s_writers.frozen = SB_UNFROZEN;  in thaw_super_locked()
1790 	sb_freeze_unlock(sb, SB_FREEZE_FS);  in thaw_super_locked()
1792 	wake_up(&sb->s_writers.wait_unfrozen);  in thaw_super_locked()
1793 	deactivate_locked_super(sb);  in thaw_super_locked()
1803 int thaw_super(struct super_block *sb)  in thaw_super()  argument
1805 	down_write(&sb->s_umount);  in thaw_super()
1806 	return thaw_super_locked(sb);  in thaw_super()