Commit 446aaa6e authored by Kazuya Mio's avatar Kazuya Mio Committed by Theodore Ts'o
Browse files

ext4: initialize moved_len before calling ext4_move_extents() 



The move_extent.moved_len is used to pass back the number of exchanged
blocks count to user space.  Currently the caller must clear this
field; but we spend more code space checking for this requirement than
simply zeroing the field ourselves, so let's just make life easier for
everyone all around.

Signed-off-by: default avatarKazuya Mio <k-mio@sx.jp.nec.com>
Signed-off-by: default avatarAkira Fujita <a-fujita@rs.jp.nec.com>
Signed-off-by: default avatar"Theodore Ts'o" <tytso@mit.edu>
parent 94d7c16c

fs/ext4/ioctl.c

+1 −0
Original line number Diff line number Diff line
@@ -239,6 +239,7 @@ setversion_out: 
			}

		}



		me.moved_len = 0;

		err = ext4_move_extents(filp, donor_filp, me.orig_start,

					me.donor_start, me.len, &me.moved_len);

		fput(donor_filp);

fs/ext4/move_extent.c

+3 −11
Original line number Diff line number Diff line
@@ -947,7 +947,6 @@ out2: 
 * @orig_start:		logical start offset in block for orig

 * @donor_start:	logical start offset in block for donor

 * @len:		the number of blocks to be moved

 * @moved_len:		moved block length

 *

 * Check the arguments of ext4_move_extents() whether the files can be

 * exchanged with each other.
@@ -956,7 +955,7 @@ out2: 
static int

mext_check_arguments(struct inode *orig_inode,

		     struct inode *donor_inode, __u64 orig_start,

			  __u64 donor_start, __u64 *len, __u64 moved_len)

		     __u64 donor_start, __u64 *len)

{

	ext4_lblk_t orig_blocks, donor_blocks;

	unsigned int blkbits = orig_inode->i_blkbits;
@@ -1010,13 +1009,6 @@ mext_check_arguments(struct inode *orig_inode, 
		return -EINVAL;

	}



	if (moved_len) {

		ext4_debug("ext4 move extent: moved_len should be 0 "

			"[ino:orig %lu, donor %lu]\n", orig_inode->i_ino,

			donor_inode->i_ino);

		return -EINVAL;

	}



	if ((orig_start > EXT_MAX_BLOCK) ||

	    (donor_start > EXT_MAX_BLOCK) ||

	    (*len > EXT_MAX_BLOCK) ||
@@ -1226,7 +1218,7 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp, 
	double_down_write_data_sem(orig_inode, donor_inode);

	/* Check the filesystem environment whether move_extent can be done */

	ret1 = mext_check_arguments(orig_inode, donor_inode, orig_start,

					donor_start, &len, *moved_len);

				    donor_start, &len);

	if (ret1)

		goto out;

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