On Mon, 2008-06-02 at 09:39 +0530, Aneesh Kumar K.V wrote: > On Sun, Jun 01, 2008 at 08:50:32PM -0700, Mingming Cao wrote: > > On Mon, 2008-06-02 at 08:44 +0530, Aneesh Kumar K.V wrote: > > > On Sun, Jun 01, 2008 at 02:10:02PM -0700, Mingming Cao wrote: > > > > ext4: Need clear buffer_delay after page writeout for delayed allocation > > > > > > > > From: Mingming Cao <cmm@xxxxxxxxxx> > > > > > > > > Need clear buffer_delay in ext4_da_writepage() after page has been writeout > > > > > > > > Signed-off-by: Mingming Cao <cmm@xxxxxxxxxx> > > > > > > > > --- > > > > > > We do that in mpage_put_bnr_to_bhs. > > > > > Normally delayed buffer could be cleared in that case, but if allocation > > failed in __mapge_da_writepages(), it will keep buffer_delay marked and > > deferring to later ext4_da_writepage() to do block allocation. This > > patch handles clear bh delay bit in this case. > > > > Why not do it in ext4_da_get_block_write then. The buffer head passed to ext4_da_get_block_write() calling from mpage_da_map_blocks is a dummy one, to store the allocated extent, not the bh that need map. > The reason being > block_write_full_page can return an error even though we have some of > the blocks allocated. With 1K block size we could allocate 3 blocks and > fail for the last block in that case with the above patch we don't > clear the delay bit of the buffer head of all the blocks allocated. > It only clear the delayed bits if block_write_full_page() returns successfully. But that reminds me to do some block reservation handling for the error case. > -aneesh > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
