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ext4: simplify mpage_add_bh_to_extent()

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The argument b_size of mpage_add_bh_to_extent() was bogus since it was
always == blocksize (which we can easily derive from inode->i_blkbits).
Also second branch of condition:
	if (nrblocks >= EXT4_MAX_TRANS_DATA) {
	} else if ((nrblocks + (b_size >> mpd->inode->i_blkbits)) >
						EXT4_MAX_TRANS_DATA) {
	}
was never taken because (b_size >> mpd->inode->i_blkbits) == 1.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
Jan Kara 2013-01-28 13:06:48 -05:00 committed by Theodore Ts'o
parent f8bec37037
commit b6a8e62f8b
1 changed files with 9 additions and 20 deletions
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29
fs/ext4/inode.c
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@ -1647,16 +1647,16 @@ submit_io:
*
* @mpd->lbh - extent of blocks
* @logical - logical number of the block in the file
* @bh - bh of the block (used to access block's state)
* @b_state - b_state of the buffer head added
*
* the function is used to collect contig. blocks in same state
*/
static void mpage_add_bh_to_extent(struct mpage_da_data *mpd,
sector_t logical, size_t b_size,
static void mpage_add_bh_to_extent(struct mpage_da_data *mpd, sector_t logical,
unsigned long b_state)
{
sector_t next;
int nrblocks = mpd->b_size >> mpd->inode->i_blkbits;
int blkbits = mpd->inode->i_blkbits;
int nrblocks = mpd->b_size >> blkbits;
/*
* XXX Don't go larger than mballoc is willing to allocate
@ -1664,11 +1664,11 @@ static void mpage_add_bh_to_extent(struct mpage_da_data *mpd,
* mpage_da_submit_io() into this function and then call
* ext4_map_blocks() multiple times in a loop
*/
if (nrblocks >= 8*1024*1024/mpd->inode->i_sb->s_blocksize)
if (nrblocks >= (8*1024*1024 >> blkbits))
goto flush_it;
/* check if thereserved journal credits might overflow */
if (!(ext4_test_inode_flag(mpd->inode, EXT4_INODE_EXTENTS))) {
/* check if the reserved journal credits might overflow */
if (!ext4_test_inode_flag(mpd->inode, EXT4_INODE_EXTENTS)) {
if (nrblocks >= EXT4_MAX_TRANS_DATA) {
/*
* With non-extent format we are limited by the journal
@ -1677,16 +1677,6 @@ static void mpage_add_bh_to_extent(struct mpage_da_data *mpd,
* nrblocks. So limit nrblocks.
*/
goto flush_it;
} else if ((nrblocks + (b_size >> mpd->inode->i_blkbits)) >
EXT4_MAX_TRANS_DATA) {
/*
* Adding the new buffer_head would make it cross the
* allowed limit for which we have journal credit
* reserved. So limit the new bh->b_size
*/
b_size = (EXT4_MAX_TRANS_DATA - nrblocks) <<
mpd->inode->i_blkbits;
/* we will do mpage_da_submit_io in the next loop */
}
}
/*
@ -1694,7 +1684,7 @@ static void mpage_add_bh_to_extent(struct mpage_da_data *mpd,
*/
if (mpd->b_size == 0) {
mpd->b_blocknr = logical;
mpd->b_size = b_size;
mpd->b_size = 1 << blkbits;
mpd->b_state = b_state & BH_FLAGS;
return;
}
@ -1704,7 +1694,7 @@ static void mpage_add_bh_to_extent(struct mpage_da_data *mpd,
* Can we merge the block to our big extent?
*/
if (logical == next && (b_state & BH_FLAGS) == mpd->b_state) {
mpd->b_size += b_size;
mpd->b_size += 1 << blkbits;
return;
}
@ -2156,7 +2146,6 @@ static int write_cache_pages_da(handle_t *handle,
*/
if (ext4_bh_delay_or_unwritten(NULL, bh)) {
mpage_add_bh_to_extent(mpd, logical,
bh->b_size,
bh->b_state);
if (mpd->io_done)
goto ret_extent_tail;