From: "Aneesh Kumar K.V" Subject: [PATCH -V3] ext4: code cleanup Date: Tue, 25 Nov 2008 22:03:16 +0530 Message-ID: <1227630796-17700-1-git-send-email-aneesh.kumar@linux.vnet.ibm.com> Cc: linux-ext4@vger.kernel.org, "Aneesh Kumar K.V" To: cmm@us.ibm.com, tytso@mit.edu, sandeen@redhat.com Return-path: Received: from e28smtp04.in.ibm.com ([59.145.155.4]:44631 "EHLO e28smtp04.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751287AbYKYQdd (ORCPT ); Tue, 25 Nov 2008 11:33:33 -0500 Received: from d28relay02.in.ibm.com (d28relay02.in.ibm.com [9.184.220.59]) by e28smtp04.in.ibm.com (8.13.1/8.13.1) with ESMTP id mAPGXJtD004049 for ; Tue, 25 Nov 2008 22:03:19 +0530 Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay02.in.ibm.com (8.13.8/8.13.8/NCO v9.1) with ESMTP id mAPGWhtD4317202 for ; Tue, 25 Nov 2008 22:02:43 +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 mAPGXJ2F005249 for ; Wed, 26 Nov 2008 03:33:19 +1100 Sender: linux-ext4-owner@vger.kernel.org List-ID: rename some variables . We also unlock locks in the reverse order we acquired as a part of cleanup. FILENAME: In between use-high-16-bits-of-bg-free-counts fix-race-between-read_inode_bitmap-and-ext4_new_inode Signed-off-by: Aneesh Kumar K.V --- fs/ext4/balloc.c | 2 +- fs/ext4/ialloc.c | 63 ++++++++++++++++++++++++++++------------------------ fs/ext4/mballoc.c | 2 +- 3 files changed, 36 insertions(+), 31 deletions(-) diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index 8dd7b0d..3cae4c6 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -329,8 +329,8 @@ ext4_read_block_bitmap(struct super_block *sb, ext4_group_t block_group) if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { ext4_init_block_bitmap(sb, bh, block_group, desc); set_buffer_uptodate(bh); - unlock_buffer(bh); spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group)); + unlock_buffer(bh); return bh; } spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group)); diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index 84f060b..229708b 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -124,8 +124,8 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group) if (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) { ext4_init_inode_bitmap(sb, bh, block_group, desc); set_buffer_uptodate(bh); - unlock_buffer(bh); spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group)); + unlock_buffer(bh); return bh; } spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group)); @@ -585,8 +585,8 @@ static int find_group_other(struct super_block *sb, struct inode *parent, struct inode *ext4_new_inode(handle_t *handle, struct inode *dir, int mode) { struct super_block *sb; - struct buffer_head *bitmap_bh = NULL; - struct buffer_head *bh2; + struct buffer_head *inode_bitmap_bh = NULL; + struct buffer_head *group_desc_bh; ext4_group_t group = 0; unsigned long ino = 0; struct inode *inode; @@ -634,40 +634,42 @@ struct inode *ext4_new_inode(handle_t *handle, struct inode *dir, int mode) for (i = 0; i < sbi->s_groups_count; i++) { err = -EIO; - gdp = ext4_get_group_desc(sb, group, &bh2); + gdp = ext4_get_group_desc(sb, group, &group_desc_bh); if (!gdp) goto fail; - brelse(bitmap_bh); - bitmap_bh = ext4_read_inode_bitmap(sb, group); - if (!bitmap_bh) + brelse(inode_bitmap_bh); + inode_bitmap_bh = ext4_read_inode_bitmap(sb, group); + if (!inode_bitmap_bh) goto fail; ino = 0; repeat_in_this_group: ino = ext4_find_next_zero_bit((unsigned long *) - bitmap_bh->b_data, EXT4_INODES_PER_GROUP(sb), ino); + inode_bitmap_bh->b_data, + EXT4_INODES_PER_GROUP(sb), ino); if (ino < EXT4_INODES_PER_GROUP(sb)) { - BUFFER_TRACE(bitmap_bh, "get_write_access"); - err = ext4_journal_get_write_access(handle, bitmap_bh); + BUFFER_TRACE(inode_bitmap_bh, "get_write_access"); + err = ext4_journal_get_write_access(handle, + inode_bitmap_bh); if (err) goto fail; if (!ext4_set_bit_atomic(sb_bgl_lock(sbi, group), - ino, bitmap_bh->b_data)) { + ino, inode_bitmap_bh->b_data)) { /* we won it */ - BUFFER_TRACE(bitmap_bh, + BUFFER_TRACE(inode_bitmap_bh, "call ext4_journal_dirty_metadata"); err = ext4_journal_dirty_metadata(handle, - bitmap_bh); + inode_bitmap_bh); if (err) goto fail; goto got; } /* we lost it */ - jbd2_journal_release_buffer(handle, bitmap_bh); + jbd2_journal_release_buffer(handle, inode_bitmap_bh); if (++ino < EXT4_INODES_PER_GROUP(sb)) goto repeat_in_this_group; @@ -698,19 +700,21 @@ struct inode *ext4_new_inode(handle_t *handle, struct inode *dir, int mode) goto fail; } - BUFFER_TRACE(bh2, "get_write_access"); - err = ext4_journal_get_write_access(handle, bh2); - if (err) goto fail; + BUFFER_TRACE(group_desc_bh, "get_write_access"); + err = ext4_journal_get_write_access(handle, group_desc_bh); + if (err) + goto fail; /* We may have to initialize the block bitmap if it isn't already */ if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM) && gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { - struct buffer_head *block_bh = ext4_read_block_bitmap(sb, group); + struct buffer_head *block_bitmap_bh; - BUFFER_TRACE(block_bh, "get block bitmap access"); - err = ext4_journal_get_write_access(handle, block_bh); + block_bitmap_bh = ext4_read_block_bitmap(sb, group); + BUFFER_TRACE(block_bitmap_bh, "get block bitmap access"); + err = ext4_journal_get_write_access(handle, block_bitmap_bh); if (err) { - brelse(block_bh); + brelse(block_bitmap_bh); goto fail; } @@ -718,8 +722,8 @@ struct inode *ext4_new_inode(handle_t *handle, struct inode *dir, int mode) spin_lock(sb_bgl_lock(sbi, group)); /* recheck and clear flag under lock if we still need to */ if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { - gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT); free = ext4_free_blocks_after_init(sb, group, gdp); + gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT); ext4_free_blks_set(sb, gdp, free); gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp); @@ -728,11 +732,12 @@ struct inode *ext4_new_inode(handle_t *handle, struct inode *dir, int mode) /* Don't need to dirty bitmap block if we didn't change it */ if (free) { - BUFFER_TRACE(block_bh, "dirty block bitmap"); - err = ext4_journal_dirty_metadata(handle, block_bh); + BUFFER_TRACE(block_bitmap_bh, "dirty block bitmap"); + err = ext4_journal_dirty_metadata(handle, + block_bitmap_bh); } - brelse(block_bh); + brelse(block_bitmap_bh); if (err) goto fail; } @@ -776,8 +781,8 @@ struct inode *ext4_new_inode(handle_t *handle, struct inode *dir, int mode) } gdp->bg_checksum = ext4_group_desc_csum(sbi, group, gdp); spin_unlock(sb_bgl_lock(sbi, group)); - BUFFER_TRACE(bh2, "call ext4_journal_dirty_metadata"); - err = ext4_journal_dirty_metadata(handle, bh2); + BUFFER_TRACE(group_desc_bh, "call ext4_journal_dirty_metadata"); + err = ext4_journal_dirty_metadata(handle, group_desc_bh); if (err) goto fail; percpu_counter_dec(&sbi->s_freeinodes_counter); @@ -876,7 +881,7 @@ struct inode *ext4_new_inode(handle_t *handle, struct inode *dir, int mode) iput(inode); ret = ERR_PTR(err); really_out: - brelse(bitmap_bh); + brelse(inode_bitmap_bh); return ret; fail_free_drop: @@ -887,7 +892,7 @@ struct inode *ext4_new_inode(handle_t *handle, struct inode *dir, int mode) inode->i_flags |= S_NOQUOTA; inode->i_nlink = 0; iput(inode); - brelse(bitmap_bh); + brelse(inode_bitmap_bh); return ERR_PTR(err); } diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index eb6aca6..97a2d4b 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -804,8 +804,8 @@ static int ext4_mb_init_cache(struct page *page, char *incore) ext4_init_block_bitmap(sb, bh[i], first_group + i, desc); set_buffer_uptodate(bh[i]); - unlock_buffer(bh[i]); spin_unlock(sb_bgl_lock(EXT4_SB(sb), first_group + i)); + unlock_buffer(bh[i]); continue; } spin_unlock(sb_bgl_lock(EXT4_SB(sb), first_group + i)); -- 1.6.0.4.735.gea4f