blkdev_issue_flush() can fail. Make sure the error gets properly propagated. Signed-off-by: Jan Kara <jack@suse.cz>
		
			
				
	
	
		
			105 lines
		
	
	
	
		
			3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			105 lines
		
	
	
	
		
			3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 *  linux/fs/ext3/fsync.c
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 *
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 *  Copyright (C) 1993  Stephen Tweedie (sct@redhat.com)
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 *  from
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 *  Copyright (C) 1992  Remy Card (card@masi.ibp.fr)
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 *                      Laboratoire MASI - Institut Blaise Pascal
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 *                      Universite Pierre et Marie Curie (Paris VI)
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 *  from
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 *  linux/fs/minix/truncate.c   Copyright (C) 1991, 1992  Linus Torvalds
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 *
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 *  ext3fs fsync primitive
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 *
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 *  Big-endian to little-endian byte-swapping/bitmaps by
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 *        David S. Miller (davem@caip.rutgers.edu), 1995
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 *
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 *  Removed unnecessary code duplication for little endian machines
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 *  and excessive __inline__s.
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 *        Andi Kleen, 1997
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 *
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 * Major simplications and cleanup - we only need to do the metadata, because
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 * we can depend on generic_block_fdatasync() to sync the data blocks.
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 */
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#include <linux/blkdev.h>
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#include <linux/writeback.h>
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#include "ext3.h"
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/*
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 * akpm: A new design for ext3_sync_file().
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 *
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 * This is only called from sys_fsync(), sys_fdatasync() and sys_msync().
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 * There cannot be a transaction open by this task.
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 * Another task could have dirtied this inode.  Its data can be in any
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 * state in the journalling system.
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 *
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 * What we do is just kick off a commit and wait on it.  This will snapshot the
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 * inode to disk.
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 */
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int ext3_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
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{
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	struct inode *inode = file->f_mapping->host;
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	struct ext3_inode_info *ei = EXT3_I(inode);
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	journal_t *journal = EXT3_SB(inode->i_sb)->s_journal;
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	int ret, needs_barrier = 0;
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	tid_t commit_tid;
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	trace_ext3_sync_file_enter(file, datasync);
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	if (inode->i_sb->s_flags & MS_RDONLY)
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		return 0;
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	ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
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	if (ret)
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		goto out;
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	J_ASSERT(ext3_journal_current_handle() == NULL);
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	/*
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	 * data=writeback,ordered:
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	 *  The caller's filemap_fdatawrite()/wait will sync the data.
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	 *  Metadata is in the journal, we wait for a proper transaction
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	 *  to commit here.
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	 *
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	 * data=journal:
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	 *  filemap_fdatawrite won't do anything (the buffers are clean).
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	 *  ext3_force_commit will write the file data into the journal and
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	 *  will wait on that.
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	 *  filemap_fdatawait() will encounter a ton of newly-dirtied pages
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	 *  (they were dirtied by commit).  But that's OK - the blocks are
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	 *  safe in-journal, which is all fsync() needs to ensure.
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	 */
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	if (ext3_should_journal_data(inode)) {
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		ret = ext3_force_commit(inode->i_sb);
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		goto out;
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	}
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	if (datasync)
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		commit_tid = atomic_read(&ei->i_datasync_tid);
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	else
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		commit_tid = atomic_read(&ei->i_sync_tid);
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	if (test_opt(inode->i_sb, BARRIER) &&
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	    !journal_trans_will_send_data_barrier(journal, commit_tid))
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		needs_barrier = 1;
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	log_start_commit(journal, commit_tid);
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	ret = log_wait_commit(journal, commit_tid);
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	/*
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	 * In case we didn't commit a transaction, we have to flush
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	 * disk caches manually so that data really is on persistent
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	 * storage
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	 */
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	if (needs_barrier) {
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		int err;
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		err = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL);
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		if (!ret)
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			ret = err;
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	}
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out:
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	trace_ext3_sync_file_exit(inode, ret);
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	return ret;
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}
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