Commit ee20808d authored by Darrick J. Wong's avatar Darrick J. Wong
Browse files

xfs: create a new helper to return a file's allocation unit 



Create a new helper function to calculate the fundamental allocation
unit (i.e. the smallest unit of space we can allocate) of a file.
Things are going to get hairy with range-exchange on the realtime
device, so prepare for this now.

Remove the static attribute from xfs_is_falloc_aligned since the next
patch will need it.

Signed-off-by: default avatarDarrick J. Wong <djwong@kernel.org>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
parent 00acb28d

fs/xfs/xfs_file.c

+12 −20
Original line number Diff line number Diff line
@@ -39,33 +39,25 @@ static const struct vm_operations_struct xfs_file_vm_ops; 
 * Decide if the given file range is aligned to the size of the fundamental

 * allocation unit for the file.

 */

static bool

bool

xfs_is_falloc_aligned(

	struct xfs_inode	*ip,

	loff_t			pos,

	long long int		len)

{

	struct xfs_mount	*mp = ip->i_mount;

	uint64_t		mask;

	unsigned int		alloc_unit = xfs_inode_alloc_unitsize(ip);



	if (XFS_IS_REALTIME_INODE(ip)) {

		if (!is_power_of_2(mp->m_sb.sb_rextsize)) {

			u64	rextbytes;

	if (!is_power_of_2(alloc_unit)) {

		u32	mod;



			rextbytes = XFS_FSB_TO_B(mp, mp->m_sb.sb_rextsize);

			div_u64_rem(pos, rextbytes, &mod);

		div_u64_rem(pos, alloc_unit, &mod);

		if (mod)

			return false;

			div_u64_rem(len, rextbytes, &mod);

		div_u64_rem(len, alloc_unit, &mod);

		return mod == 0;

	}

		mask = XFS_FSB_TO_B(mp, mp->m_sb.sb_rextsize) - 1;

	} else {

		mask = mp->m_sb.sb_blocksize - 1;

	}



	return !((pos | len) & mask);

	return !((pos | len) & (alloc_unit - 1));

}



/*

fs/xfs/xfs_file.h

+3 −0
Original line number Diff line number Diff line
@@ -9,4 +9,7 @@ 
extern const struct file_operations xfs_file_operations;

extern const struct file_operations xfs_dir_file_operations;



bool xfs_is_falloc_aligned(struct xfs_inode *ip, loff_t pos,

		long long int len);



#endif /* __XFS_FILE_H__ */

fs/xfs/xfs_inode.c

+13 −0
Original line number Diff line number Diff line
@@ -4008,3 +4008,16 @@ xfs_break_layouts( 


	return error;

}



/* Returns the size of fundamental allocation unit for a file, in bytes. */

unsigned int

xfs_inode_alloc_unitsize(

	struct xfs_inode	*ip)

{

	unsigned int		blocks = 1;



	if (XFS_IS_REALTIME_INODE(ip))

		blocks = ip->i_mount->m_sb.sb_rextsize;



	return XFS_FSB_TO_B(ip->i_mount, blocks);

}

fs/xfs/xfs_inode.h

+1 −0
Original line number Diff line number Diff line
@@ -625,6 +625,7 @@ int xfs_inode_reload_unlinked(struct xfs_inode *ip); 
bool xfs_ifork_zapped(const struct xfs_inode *ip, int whichfork);

void xfs_inode_count_blocks(struct xfs_trans *tp, struct xfs_inode *ip,

		xfs_filblks_t *dblocks, xfs_filblks_t *rblocks);

unsigned int xfs_inode_alloc_unitsize(struct xfs_inode *ip);



struct xfs_dir_update_params {

	const struct xfs_inode	*dp;