On Tue, 2006-09-05 at 13:14 -0700, Badari Pulavarty wrote:
Dave Kleikamp wrote:
I'm having a hard time figuring out exactly what ext3_get_blocks_handle
is trying to return, but it looks to me like if it is allocating one
data block, and needs to allocate an indirect block as well, then it
will return 2 rather than 1. Is this expected, or am I just confused?
It would return "1" in that case.. (data block)
> 0 means get_block() suceeded and indicates the number of blocks mapped
= 0 lookup failed
< 0 mean error case
Okay, I got confused looking through the code. I still don't see how
ext3_get_blocks_handle() should be returning a number greater than
maxblocks.
I did search for callers of ext3_get_blocks_handle() and found that
ext3_readdir() seems to do wrong thing all the time with error check :(
Need to take a closer look..
err = ext3_get_blocks_handle(NULL, inode, blk, 1,
&map_bh, 0, 0);
if (err > 0) { <<<< BAD
page_cache_readahead(sb->s_bdev->bd_inode->i_mapping,
&filp->f_ra,
filp,
map_bh.b_blocknr >>
(PAGE_CACHE_SHIFT - inode->i_blkbits),
1);
bh = ext3_bread(NULL, inode, blk, 0, &err);
}
Bad to do what it's doing, or bad to call name the variable "err"?
I think if it looked like this:
count = ext3_get_blocks_handle(NULL, inode, blk, 1,
&map_bh, 0, 0);
if (count > 0) {
it would be a lot less confusing.
I am sorry !! it is doing the right thing :(
Not your fault. The variable is very badly named.