From nobody Mon Sep 17 00:00:00 2001 From: Joel Becker Date: Wed, 2 May 2007 11:26:12 -0700 Subject: ocfs2: Wrap access of directory allocations with ip_alloc_sem. OCFS2_I(inode)->ip_alloc_sem is a read-write semaphore protecting local concurrent access of ocfs2 inodes. However, ocfs2 directories were not taking the semaphore while they accessed or modified the allocation tree. ocfs2_extend_dir() needs to take the semaphore in a write mode when it adds to the allocation. All other directory users get there via ocfs2_bread(), which takes the semaphore in read mode. Signed-off-by: Joel Becker Signed-off-by: Mark Fasheh --- fs/ocfs2/dir.c | 7 ++++++- fs/ocfs2/inode.c | 2 ++ 2 files changed, 8 insertions(+), 1 deletions(-) 42bc3f222b881eb5e1322529b13efd611ac060c8 diff --git a/fs/ocfs2/dir.c b/fs/ocfs2/dir.c index 66821e1..fd41f8b 100644 --- a/fs/ocfs2/dir.c +++ b/fs/ocfs2/dir.c @@ -402,7 +402,7 @@ static int ocfs2_extend_dir(struct ocfs2 struct buffer_head **new_de_bh) { int status = 0; - int credits, num_free_extents; + int credits, num_free_extents, drop_alloc_sem = 0; loff_t dir_i_size; struct ocfs2_dinode *fe = (struct ocfs2_dinode *) parent_fe_bh->b_data; struct ocfs2_alloc_context *data_ac = NULL; @@ -451,6 +451,9 @@ static int ocfs2_extend_dir(struct ocfs2 credits = OCFS2_SIMPLE_DIR_EXTEND_CREDITS; } + down_write(&OCFS2_I(dir)->ip_alloc_sem); + drop_alloc_sem = 1; + handle = ocfs2_start_trans(osb, credits); if (IS_ERR(handle)) { status = PTR_ERR(handle); @@ -496,6 +499,8 @@ static int ocfs2_extend_dir(struct ocfs2 *new_de_bh = new_bh; get_bh(*new_de_bh); bail: + if (drop_alloc_sem) + up_write(&OCFS2_I(dir)->ip_alloc_sem); if (handle) ocfs2_commit_trans(osb, handle); diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c index 28ab56f..480d90f 100644 --- a/fs/ocfs2/inode.c +++ b/fs/ocfs2/inode.c @@ -1121,8 +1121,10 @@ struct buffer_head *ocfs2_bread(struct i return NULL; } + down_read(&OCFS2_I(inode)->ip_alloc_sem); tmperr = ocfs2_extent_map_get_blocks(inode, block, 1, &p_blkno, NULL); + up_read(&OCFS2_I(inode)->ip_alloc_sem); if (tmperr < 0) { mlog_errno(tmperr); goto fail; -- 1.3.3