1 // SPDX-License-Identifier: GPL-2.0
3  * High-level sync()-related operations
19 #include <linux/backing-dev.h>
38 	WARN_ON(!rwsem_is_locked(&sb->s_umount));  in sync_filesystem()
41 	 * No point in syncing out anything if the filesystem is read-only.  in sync_filesystem()
55 	if (sb->s_op->sync_fs) {  in sync_filesystem()
56 		ret = sb->s_op->sync_fs(sb, 0);  in sync_filesystem()
60 	ret = sync_blockdev_nowait(sb->s_bdev);  in sync_filesystem()
65 	if (sb->s_op->sync_fs) {  in sync_filesystem()
66 		ret = sb->s_op->sync_fs(sb, 1);  in sync_filesystem()
70 	return sync_blockdev(sb->s_bdev);  in sync_filesystem()
82 	if (!sb_rdonly(sb) && !(sb->s_iflags & SB_I_SKIP_SYNC) &&  in sync_fs_one_sb()
83 	    sb->s_op->sync_fs)  in sync_fs_one_sb()
84 		sb->s_op->sync_fs(sb, *(int *)arg);  in sync_fs_one_sb()
88  * Sync everything. We start by waking flusher threads so that most of
89  * writeback runs on all devices in parallel. Then we sync all inodes reliably
92  * and we tell filesystems to sync their metadata via ->sync_fs() calls.
95  * and do not sync it on their own in ->sync_fs().
111 SYSCALL_DEFINE0(sync)  in SYSCALL_DEFINE0()  argument
122 	 * Sync twice to reduce the possibility we skipped some inodes / pages  in do_sync_work()
131 	printk("Emergency Sync complete\n");  in do_sync_work()
147  * sync a single super
156 		return -EBADF;  in SYSCALL_DEFINE1()
157 	sb = fd_file(f)->f_path.dentry->d_sb;  in SYSCALL_DEFINE1()
159 	down_read(&sb->s_umount);  in SYSCALL_DEFINE1()
161 	up_read(&sb->s_umount);  in SYSCALL_DEFINE1()
163 	ret2 = errseq_check_and_advance(&sb->s_wb_err, &fd_file(f)->f_sb_err);  in SYSCALL_DEFINE1()
170  * vfs_fsync_range - helper to sync a range of data & metadata to disk
171  * @file:		file to sync
172  * @start:		offset in bytes of the beginning of data range to sync
182 	struct inode *inode = file->f_mapping->host;  in vfs_fsync_range()
184 	if (!file->f_op->fsync)  in vfs_fsync_range()
185 		return -EINVAL;  in vfs_fsync_range()
186 	if (!datasync && (inode->i_state & I_DIRTY_TIME))  in vfs_fsync_range()
188 	return file->f_op->fsync(file, start, end, datasync);  in vfs_fsync_range()
193  * vfs_fsync - perform a fsync or fdatasync on a file
194  * @file:		file to sync
209 	int ret = -EBADF;  in do_fsync()
236 	ret = -EINVAL;  in sync_file_range()
269 		endbyte--;		/* inclusive */  in sync_file_range()
271 	i_mode = file_inode(file)->i_mode;  in sync_file_range()
272 	ret = -ESPIPE;  in sync_file_range()
277 	mapping = file->f_mapping;  in sync_file_range()
307  * a file in the range offset .. (offset+nbytes-1) inclusive.  If nbytes is
310  * The flag bits are:
322  * Useful combinations of the flag bits are:
326  * under writeout.  This is a start-write-for-data-integrity operation.
329  * are not presently under writeout.  This is an asynchronous flush-to-disk
339  * a traditional sync() operation.  This is a write-for-data-integrity operation
352  * already-instantiated disk blocks, there are no guarantees here that the data
361 	ret = -EBADF;  in ksys_sync_file_range()