From 7ed122e42c72b3e4531f8b4a9f72159e8303ac15 Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Wed, 10 Dec 2008 10:28:10 +0000 Subject: GFS2: Streamline alloc calculations for writes This patch removes some unused code, and make the calculation of the number of blocks required conditional in order to reduce the number of times this (potentially expensive) calculation is done. Signed-off-by: Steven Whitehouse --- fs/gfs2/bmap.h | 34 ++++++++++++++++++++++++++++++---- 1 file changed, 30 insertions(+), 4 deletions(-) (limited to 'fs/gfs2/bmap.h') diff --git a/fs/gfs2/bmap.h b/fs/gfs2/bmap.h index 4e6cde2943b..c983177e05a 100644 --- a/fs/gfs2/bmap.h +++ b/fs/gfs2/bmap.h @@ -10,10 +10,40 @@ #ifndef __BMAP_DOT_H__ #define __BMAP_DOT_H__ +#include "inode.h" + struct inode; struct gfs2_inode; struct page; + +/** + * gfs2_write_calc_reserv - calculate number of blocks needed to write to a file + * @ip: the file + * @len: the number of bytes to be written to the file + * @data_blocks: returns the number of data blocks required + * @ind_blocks: returns the number of indirect blocks required + * + */ + +static inline void gfs2_write_calc_reserv(const struct gfs2_inode *ip, + unsigned int len, + unsigned int *data_blocks, + unsigned int *ind_blocks) +{ + const struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); + unsigned int tmp; + + BUG_ON(gfs2_is_dir(ip)); + *data_blocks = (len >> sdp->sd_sb.sb_bsize_shift) + 3; + *ind_blocks = 3 * (sdp->sd_max_height - 1); + + for (tmp = *data_blocks; tmp > sdp->sd_diptrs;) { + tmp = DIV_ROUND_UP(tmp, sdp->sd_inptrs); + *ind_blocks += tmp; + } +} + int gfs2_unstuff_dinode(struct gfs2_inode *ip, struct page *page); int gfs2_block_map(struct inode *inode, sector_t lblock, struct buffer_head *bh, int create); int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsigned *extlen); @@ -21,10 +51,6 @@ int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsi int gfs2_truncatei(struct gfs2_inode *ip, u64 size); int gfs2_truncatei_resume(struct gfs2_inode *ip); int gfs2_file_dealloc(struct gfs2_inode *ip); - -void gfs2_write_calc_reserv(struct gfs2_inode *ip, unsigned int len, - unsigned int *data_blocks, - unsigned int *ind_blocks); int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset, unsigned int len, int *alloc_required); -- cgit v1.2.3-70-g09d2