From f101d38dd375dc0ade6b9c3fe4bf19812d9e14cc Mon Sep 17 00:00:00 2001 From: Yongqiang Yang Date: Mon, 4 Apr 2011 15:40:24 -0400 Subject: [PATCH] ext4: fix credits computing for indirect mapped files commit 5b41395fcc0265fc9f193aef9df39ce49d64677c upstream. When writing a contiguous set of blocks, two indirect blocks could be needed depending on how the blocks are aligned, so we need to increase the number of credits needed by one. [ Also fixed a another bug which could further underestimate the number of journal credits needed by 1; the code was using integer division instead of DIV_ROUND_UP() -- tytso] Signed-off-by: Yongqiang Yang Signed-off-by: "Theodore Ts'o" Signed-off-by: Greg Kroah-Hartman --- fs/ext4/inode.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 1b23f9d2ef56..8572c791fd52 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -5458,13 +5458,12 @@ static int ext4_indirect_trans_blocks(struct inode *inode, int nrblocks, /* if nrblocks are contiguous */ if (chunk) { /* - * With N contiguous data blocks, it need at most - * N/EXT4_ADDR_PER_BLOCK(inode->i_sb) indirect blocks - * 2 dindirect blocks - * 1 tindirect block + * With N contiguous data blocks, we need at most + * N/EXT4_ADDR_PER_BLOCK(inode->i_sb) + 1 indirect blocks, + * 2 dindirect blocks, and 1 tindirect block */ - indirects = nrblocks / EXT4_ADDR_PER_BLOCK(inode->i_sb); - return indirects + 3; + return DIV_ROUND_UP(nrblocks, + EXT4_ADDR_PER_BLOCK(inode->i_sb)) + 4; } /* * if nrblocks are not contiguous, worse case, each block touch -- 2.34.1