Commit 1a485fc1 authored by Allison Collins's avatar Allison Collins Committed by Darrick J. Wong
Browse files

xfs: Factor out new helper functions xfs_attr_rmtval_set 



Break xfs_attr_rmtval_set into two helper functions
xfs_attr_rmt_find_hole and xfs_attr_rmtval_set_value.
xfs_attr_rmtval_set rolls the transaction between the helpers, but
delayed operations cannot.  We will use the helpers later when
constructing new delayed attribute routines.

Signed-off-by: default avatarAllison Collins <allison.henderson@oracle.com>
Reviewed-by: default avatarBrian Foster <bfoster@redhat.com>
Reviewed-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: default avatarChandan Rajendra <chandanrlinux@gmail.com>
Signed-off-by: default avatarDarrick J. Wong <darrick.wong@oracle.com>
Acked-by: default avatarDave Chinner <dchinner@redhat.com>
parent deed9512

fs/xfs/libxfs/xfs_attr_remote.c

+92 −57
Original line number Diff line number Diff line
@@ -440,32 +440,23 @@ xfs_attr_rmtval_get( 
}



/*

 * Write the value associated with an attribute into the out-of-line buffer

 * that we have defined for it.

 * Find a "hole" in the attribute address space large enough for us to drop the

 * new attribute's value into

 */

int

xfs_attr_rmtval_set(

STATIC int

xfs_attr_rmt_find_hole(

	struct xfs_da_args	*args)

{

	struct xfs_inode	*dp = args->dp;

	struct xfs_mount	*mp = dp->i_mount;

	struct xfs_bmbt_irec	map;

	xfs_dablk_t		lblkno;

	xfs_fileoff_t		lfileoff = 0;

	uint8_t			*src = args->value;

	int			blkcnt;

	int			valuelen;

	int			nmap;

	int			error;

	int			offset = 0;



	trace_xfs_attr_rmtval_set(args);

	int			blkcnt;

	xfs_fileoff_t		lfileoff = 0;



	/*

	 * Find a "hole" in the attribute address space large enough for

	 * us to drop the new attribute's value into. Because CRC enable

	 * attributes have headers, we can't just do a straight byte to FSB

	 * conversion and have to take the header space into account.

	 * Because CRC enable attributes have headers, we can't just do a

	 * straight byte to FSB conversion and have to take the header space

	 * into account.

	 */

	blkcnt = xfs_attr3_rmt_blocks(mp, args->rmtvaluelen);

	error = xfs_bmap_first_unused(args->trans, args->dp, blkcnt, &lfileoff,
@@ -473,49 +464,27 @@ xfs_attr_rmtval_set( 
	if (error)

		return error;



	args->rmtblkno = lblkno = (xfs_dablk_t)lfileoff;

	args->rmtblkno = (xfs_dablk_t)lfileoff;

	args->rmtblkcnt = blkcnt;



	/*

	 * Roll through the "value", allocating blocks on disk as required.

	 */

	while (blkcnt > 0) {

		/*

		 * Allocate a single extent, up to the size of the value.

		 *

		 * Note that we have to consider this a data allocation as we

		 * write the remote attribute without logging the contents.

		 * Hence we must ensure that we aren't using blocks that are on

		 * the busy list so that we don't overwrite blocks which have

		 * recently been freed but their transactions are not yet

		 * committed to disk. If we overwrite the contents of a busy

		 * extent and then crash then the block may not contain the

		 * correct metadata after log recovery occurs.

		 */

		nmap = 1;

		error = xfs_bmapi_write(args->trans, dp, (xfs_fileoff_t)lblkno,

				  blkcnt, XFS_BMAPI_ATTRFORK, args->total, &map,

				  &nmap);

		if (error)

			return error;

		error = xfs_defer_finish(&args->trans);

		if (error)

			return error;



		ASSERT(nmap == 1);

		ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&

		       (map.br_startblock != HOLESTARTBLOCK));

		lblkno += map.br_blockcount;

		blkcnt -= map.br_blockcount;



		/*

		 * Start the next trans in the chain.

		 */

		error = xfs_trans_roll_inode(&args->trans, dp);

		if (error)

			return error;

	return 0;

}



STATIC int

xfs_attr_rmtval_set_value(

	struct xfs_da_args	*args)

{

	struct xfs_inode	*dp = args->dp;

	struct xfs_mount	*mp = dp->i_mount;

	struct xfs_bmbt_irec	map;

	xfs_dablk_t		lblkno;

	uint8_t			*src = args->value;

	int			blkcnt;

	int			valuelen;

	int			nmap;

	int			error;

	int			offset = 0;



	/*

	 * Roll through the "value", copying the attribute value to the

	 * already-allocated blocks.  Blocks are written synchronously
@@ -594,6 +563,72 @@ xfs_attr_rmtval_stale( 
	return 0;

}



/*

 * Write the value associated with an attribute into the out-of-line buffer

 * that we have defined for it.

 */

int

xfs_attr_rmtval_set(

	struct xfs_da_args	*args)

{

	struct xfs_inode	*dp = args->dp;

	struct xfs_bmbt_irec	map;

	xfs_dablk_t		lblkno;

	int			blkcnt;

	int			nmap;

	int			error;



	trace_xfs_attr_rmtval_set(args);



	error = xfs_attr_rmt_find_hole(args);

	if (error)

		return error;



	blkcnt = args->rmtblkcnt;

	lblkno = (xfs_dablk_t)args->rmtblkno;

	/*

	 * Roll through the "value", allocating blocks on disk as required.

	 */

	while (blkcnt > 0) {

		/*

		 * Allocate a single extent, up to the size of the value.

		 *

		 * Note that we have to consider this a data allocation as we

		 * write the remote attribute without logging the contents.

		 * Hence we must ensure that we aren't using blocks that are on

		 * the busy list so that we don't overwrite blocks which have

		 * recently been freed but their transactions are not yet

		 * committed to disk. If we overwrite the contents of a busy

		 * extent and then crash then the block may not contain the

		 * correct metadata after log recovery occurs.

		 */

		nmap = 1;

		error = xfs_bmapi_write(args->trans, dp, (xfs_fileoff_t)lblkno,

				  blkcnt, XFS_BMAPI_ATTRFORK, args->total, &map,

				  &nmap);

		if (error)

			return error;

		error = xfs_defer_finish(&args->trans);

		if (error)

			return error;



		ASSERT(nmap == 1);

		ASSERT((map.br_startblock != DELAYSTARTBLOCK) &&

		       (map.br_startblock != HOLESTARTBLOCK));

		lblkno += map.br_blockcount;

		blkcnt -= map.br_blockcount;



		/*

		 * Start the next trans in the chain.

		 */

		error = xfs_trans_roll_inode(&args->trans, dp);

		if (error)

			return error;

	}



	return xfs_attr_rmtval_set_value(args);

}



/*

 * Remove the value associated with an attribute by deleting the

 * out-of-line buffer that it is stored on.

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