Mingming <cmm@xxxxxxxxxx> writes: > On Tue, 2009-11-24 at 01:58 +0300, Dmitry Monakhov wrote: >> This patch fix most visible problems with delalloc+quota issues >> - ext4_get_reserved_space() must return bytes instead of blocks. >> - Claim allocated meta blocks. Do it as we do for data blocks >> but delay it untill proper moment. >> - Move space claiming to ext4_da_update_reserve_space() >> Only here we do know what we are dealing with data or metadata >> > > Thanks for sending the first fix, I am actually surprisely to know the > fix didn't get merged before, as Jan has pointed this out when he review > the original patch and I have get this fixed...somehow the latest patch > wasn't being picked at the end. > > here it is. > http://marc.info/?l=linux-ext4&m=123185939602949&w=2 > > > About the second and third issue you are trying to fix here... I think > the current code does what you want already. > > The current code does reserve quota for metadata blocks at > ext4_da_update_reserve_space() already and delay the quota claim at the > later time when metadata blocks are really allocated (via > ext4_mb_mark_diskspace_used), extra reserved quota for metadata blocks > will get freed at ext4_da_update_reserve_space(). > ext4_mb_mark_diskspace_used() is called for every block allocation > including medatadata allocation, so we won't miss quota claim for > metadata there. > > The reason that I keep all quota claim immediately at the block > allocation time via ext4_mb_mark_diskspace_used() is to keep the block > allocation space accounting/dirty/delayed block space accounting/quota > accounting in the same place; Plus, when ext4_da_update_reserve_space() > called, the number of blocks passed is the number of blocks mapped, may > not necessarilly the the number of blocks just new allocated. You have reviewed wrong patch version. Please read the latest one http://article.gmane.org/gmane.comp.file-systems.ext4/16629 in order to get my idea. But in fact as Aneesh have spotted, my I've missed important issue aka #14739. Currently I'm working on new patch set version. This patch series will fix "chown vs truncate issue" and #14739 by one shot. > > cheers, > Mingming > > put the space claiming under >> The most useful test case for delalloc+quota is concurent tasks >> with write+truncate vs chown for a same file. >> >> Signed-off-by: Dmitry Monakhov <dmonakhov@xxxxxxxxxx> >> --- >> fs/ext4/inode.c | 12 ++++++++---- >> fs/ext4/mballoc.c | 6 ------ >> 2 files changed, 8 insertions(+), 10 deletions(-) >> >> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c >> index ab22297..e642cdb 100644 >> --- a/fs/ext4/inode.c >> +++ b/fs/ext4/inode.c >> @@ -1057,7 +1057,7 @@ qsize_t ext4_get_reserved_space(struct inode *inode) >> EXT4_I(inode)->i_reserved_meta_blocks; >> spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); >> >> - return total; >> + return (total << inode->i_blkbits); >> } > > > >> /* >> * Calculate the number of metadata blocks need to reserve >> @@ -1096,7 +1096,7 @@ static int ext4_calc_metadata_amount(struct inode *inode, int blocks) >> static void ext4_da_update_reserve_space(struct inode *inode, int used) >> { >> struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); >> - int total, mdb, mdb_free; >> + int total, mdb, mdb_free, mdb_claim = 0; >> >> spin_lock(&EXT4_I(inode)->i_block_reservation_lock); >> /* recalculate the number of metablocks still need to be reserved */ >> @@ -1109,7 +1109,9 @@ static void ext4_da_update_reserve_space(struct inode *inode, int used) >> >> if (mdb_free) { >> /* Account for allocated meta_blocks */ >> - mdb_free -= EXT4_I(inode)->i_allocated_meta_blocks; >> + mdb_claim = EXT4_I(inode)->i_allocated_meta_blocks; >> + BUG_ON(mdb_free < mdb_claim); >> + mdb_free -= mdb_claim; >> >> /* update fs dirty blocks counter */ >> percpu_counter_sub(&sbi->s_dirtyblocks_counter, mdb_free); >> @@ -1119,7 +1121,9 @@ static void ext4_da_update_reserve_space(struct inode *inode, int used) >> >> /* update per-inode reservations */ >> BUG_ON(used > EXT4_I(inode)->i_reserved_data_blocks); >> - EXT4_I(inode)->i_reserved_data_blocks -= used; >> + EXT4_I(inode)->i_reserved_data_blocks -= used; >> + percpu_counter_sub(&sbi->s_dirtyblocks_counter, used + mdb_claim); >> + vfs_dq_claim_block(inode, used + mdb_claim); >> spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); >> >> /* >> diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c >> index bba1282..d4c52db 100644 >> --- a/fs/ext4/mballoc.c >> +++ b/fs/ext4/mballoc.c >> @@ -2750,12 +2750,6 @@ ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac, >> if (!(ac->ac_flags & EXT4_MB_DELALLOC_RESERVED)) >> /* release all the reserved blocks if non delalloc */ >> percpu_counter_sub(&sbi->s_dirtyblocks_counter, reserv_blks); >> - else { >> - percpu_counter_sub(&sbi->s_dirtyblocks_counter, >> - ac->ac_b_ex.fe_len); >> - /* convert reserved quota blocks to real quota blocks */ >> - vfs_dq_claim_block(ac->ac_inode, ac->ac_b_ex.fe_len); >> - } >> >> if (sbi->s_log_groups_per_flex) { >> ext4_group_t flex_group = ext4_flex_group(sbi, > > > -- > 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
