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.c | 49 +++++++------------------------------------------ 1 file changed, 7 insertions(+), 42 deletions(-) (limited to 'fs/gfs2/bmap.c') diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c index 789f28cfdc2..11ffc56f1f8 100644 --- a/fs/gfs2/bmap.c +++ b/fs/gfs2/bmap.c @@ -1230,35 +1230,6 @@ int gfs2_file_dealloc(struct gfs2_inode *ip) return trunc_dealloc(ip, 0); } -/** - * 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 - * - */ - -void gfs2_write_calc_reserv(struct gfs2_inode *ip, unsigned int len, - unsigned int *data_blocks, unsigned int *ind_blocks) -{ - struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); - unsigned int tmp; - - if (gfs2_is_dir(ip)) { - *data_blocks = DIV_ROUND_UP(len, sdp->sd_jbsize) + 2; - *ind_blocks = 3 * (sdp->sd_max_jheight - 1); - } else { - *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; - } -} - /** * gfs2_write_alloc_required - figure out if a write will require an allocation * @ip: the file being written to @@ -1276,6 +1247,7 @@ int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset, struct buffer_head bh; unsigned int shift; u64 lblock, lblock_stop, size; + u64 end_of_file; *alloc_required = 0; @@ -1291,19 +1263,12 @@ int gfs2_write_alloc_required(struct gfs2_inode *ip, u64 offset, *alloc_required = 1; shift = sdp->sd_sb.sb_bsize_shift; - if (gfs2_is_dir(ip)) { - unsigned int bsize = sdp->sd_jbsize; - lblock = offset; - do_div(lblock, bsize); - lblock_stop = offset + len + bsize - 1; - do_div(lblock_stop, bsize); - } else { - u64 end_of_file = (ip->i_disksize + sdp->sd_sb.sb_bsize - 1) >> shift; - lblock = offset >> shift; - lblock_stop = (offset + len + sdp->sd_sb.sb_bsize - 1) >> shift; - if (lblock_stop > end_of_file) - return 0; - } + BUG_ON(gfs2_is_dir(ip)); + end_of_file = (ip->i_disksize + sdp->sd_sb.sb_bsize - 1) >> shift; + lblock = offset >> shift; + lblock_stop = (offset + len + sdp->sd_sb.sb_bsize - 1) >> shift; + if (lblock_stop > end_of_file) + return 0; size = (lblock_stop - lblock) << shift; do { -- cgit v1.2.3