From: "Aneesh Kumar K.V" Subject: [PATCH] ext4: delalloc block reservation fix Date: Tue, 3 Jun 2008 22:59:37 +0530 Message-ID: <1212514177-7249-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Cc: linux-ext4@vger.kernel.org, "Aneesh Kumar K.V" To: cmm@us.ibm.com Return-path: Received: from e28smtp06.in.ibm.com ([59.145.155.6]:39119 "EHLO e28smtp06.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753385AbYFCR3z (ORCPT ); Tue, 3 Jun 2008 13:29:55 -0400 Received: from d28relay04.in.ibm.com (d28relay04.in.ibm.com [9.184.220.61]) by e28smtp06.in.ibm.com (8.13.1/8.13.1) with ESMTP id m53HTc7h008889 for ; Tue, 3 Jun 2008 22:59:38 +0530 Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay04.in.ibm.com (8.13.8/8.13.8/NCO v8.7) with ESMTP id m53HTNJT1257556 for ; Tue, 3 Jun 2008 22:59:23 +0530 Received: from d28av04.in.ibm.com (loopback [127.0.0.1]) by d28av04.in.ibm.com (8.13.1/8.13.3) with ESMTP id m53HTbvi002818 for ; Tue, 3 Jun 2008 22:59:37 +0530 Sender: linux-ext4-owner@vger.kernel.org List-ID: a) We need to decrement the meta data blocks that got allocated from percpu s_freeblocks_counter b) We need to protect the reservation block counter so that reserve and release space doesn't race each other. c) don't check for free space in ext4_mb_new_blocks with delalloc We already reserved the space. Signed-off-by: Aneesh Kumar K.V --- fs/ext4/balloc.c | 9 +++++++++ fs/ext4/ext4_i.h | 2 ++ fs/ext4/inode.c | 36 +++++++++++++++++++++++------------- fs/ext4/mballoc.c | 7 ++++++- fs/ext4/super.c | 2 ++ 5 files changed, 42 insertions(+), 14 deletions(-) diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index 71b184c..bd18ceb 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -1959,6 +1959,15 @@ ext4_fsblk_t ext4_new_meta_block(handle_t *handle, struct inode *inode, ar.goal = goal; ar.len = 1; ret = ext4_mb_new_blocks(handle, &ar, errp); + /* + * Account for the allocated meta blocks + */ + if (!(*errp)) { + spin_lock(&EXT4_I(inode)->i_block_reservation_lock); + EXT4_I(inode)->i_allocated_meta_blocks += ar.len; + spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); + } + return ret; } ext4_fsblk_t ext4_new_meta_blocks(handle_t *handle, struct inode *inode, diff --git a/fs/ext4/ext4_i.h b/fs/ext4/ext4_i.h index 425518e..3d08e5b 100644 --- a/fs/ext4/ext4_i.h +++ b/fs/ext4/ext4_i.h @@ -166,7 +166,9 @@ struct ext4_inode_info { /* allocation reservation info for delalloc */ unsigned long i_reserved_data_blocks; unsigned long i_reserved_meta_blocks; + unsigned long i_allocated_meta_blocks; unsigned short i_delalloc_reserved_flag; + spinlock_t i_block_reservation_lock; }; #endif /* _EXT4_I */ diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 1695ecc..2e485a3 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -1426,11 +1426,12 @@ static int ext4_da_reserve_space(struct inode *inode, int nrblocks) struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); unsigned long md_needed, mdblocks, total = 0; - /* - * calculate the amount of metadata blocks to reserve - * in order to allocate nrblocks - * worse case is one extent per block - */ + /* + * recalculate the amount of metadata blocks to reserve + * in order to allocate nrblocks + * worse case is one extent per block + */ + spin_lock(&EXT4_I(inode)->i_block_reservation_lock); total = EXT4_I(inode)->i_reserved_data_blocks + nrblocks; mdblocks = ext4_ext_calc_metadata_amount(inode, total); BUG_ON(mdblocks < EXT4_I(inode)->i_reserved_meta_blocks); @@ -1438,42 +1439,51 @@ static int ext4_da_reserve_space(struct inode *inode, int nrblocks) md_needed = mdblocks - EXT4_I(inode)->i_reserved_meta_blocks; total = md_needed + nrblocks; - if (ext4_has_free_blocks(sbi, total) < total) + if (ext4_has_free_blocks(sbi, total) < total) { + spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); return -ENOSPC; + } /* reduce fs free blocks counter */ percpu_counter_sub(&sbi->s_freeblocks_counter, total); EXT4_I(inode)->i_reserved_data_blocks += nrblocks; - EXT4_I(inode)->i_reserved_meta_blocks += md_needed; + EXT4_I(inode)->i_reserved_meta_blocks = mdblocks; + spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); return 0; /* success */ } void ext4_da_release_space(struct inode *inode, int used, int to_free) { struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb); - int total, mdb, release; + int total, mdb, mdb_free, release; - /* calculate the number of metablocks still need to be reserved */ + spin_lock(&EXT4_I(inode)->i_block_reservation_lock); + /* recalculate the number of metablocks still need to be reserved */ total = EXT4_I(inode)->i_reserved_data_blocks - used - to_free; mdb = ext4_ext_calc_metadata_amount(inode, total); /* figure out how many metablocks to release */ BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks); - mdb = EXT4_I(inode)->i_reserved_meta_blocks - mdb; + mdb_free = EXT4_I(inode)->i_reserved_meta_blocks - mdb; + + /* Account for allocated meta_blocks */ + mdb_free -= EXT4_I(inode)->i_allocated_meta_blocks; - release = to_free + mdb; + release = to_free + mdb_free; /* update fs free blocks counter for truncate case */ percpu_counter_add(&sbi->s_freeblocks_counter, release); /* update per-inode reservations */ BUG_ON(used + to_free > EXT4_I(inode)->i_reserved_data_blocks); - EXT4_I(inode)->i_reserved_data_blocks -= used + to_free; + EXT4_I(inode)->i_reserved_data_blocks -= (used + to_free); BUG_ON(mdb > EXT4_I(inode)->i_reserved_meta_blocks); - EXT4_I(inode)->i_reserved_meta_blocks -= mdb; + EXT4_I(inode)->i_reserved_meta_blocks = mdb; + EXT4_I(inode)->i_allocated_meta_blocks = 0; + spin_unlock(&EXT4_I(inode)->i_block_reservation_lock); } static void ext4_da_page_release_reservation(struct page *page, diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index a7bdacb..09922ae 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -4052,7 +4052,12 @@ ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle, &(ar->len), errp); return block; } - ar->len = ext4_has_free_blocks(sbi, ar->len); + if (!EXT4_I(ar->inode)->i_delalloc_reserved_flag) { + /* + * With delalloc we already reserved the blocks + */ + ar->len = ext4_has_free_blocks(sbi, ar->len); + } if (ar->len == 0) { *errp = -ENOSPC; diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 073bb2c..ee036af 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -574,7 +574,9 @@ static struct inode *ext4_alloc_inode(struct super_block *sb) spin_lock_init(&ei->i_prealloc_lock); ei->i_reserved_data_blocks = 0; ei->i_reserved_meta_blocks = 0; + ei->i_allocated_meta_blocks = 0; ei->i_delalloc_reserved_flag = 0; + spin_lock_init(&(ei->i_block_reservation_lock)); return &ei->vfs_inode; } -- 1.5.5.1.357.g1af8b.dirty