From 201913ed746c7724a40d33ee5a0b6a1fd2ef3193 Mon Sep 17 00:00:00 2001 From: Ryusuke Konishi Date: Tue, 28 Apr 2009 21:04:59 +0900 Subject: nilfs2: fix circular locking dependency of writer mutex This fixes the following circular locking dependency problem: ======================================================= [ INFO: possible circular locking dependency detected ] 2.6.30-rc3 #5 ------------------------------------------------------- segctord/3895 is trying to acquire lock: (&nilfs->ns_writer_mutex){+.+...}, at: [] nilfs_mdt_get_block+0x89/0x20f [nilfs2] but task is already holding lock: (&bmap->b_sem){++++..}, at: [] nilfs_bmap_propagate+0x14/0x2e [nilfs2] which lock already depends on the new lock. The bugfix is done by replacing call sites of nilfs_get_writer() which are never called from read-only context with direct dereferencing of pointer to a writable FS-instance. Signed-off-by: Ryusuke Konishi --- fs/nilfs2/mdt.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) (limited to 'fs/nilfs2/mdt.c') diff --git a/fs/nilfs2/mdt.c b/fs/nilfs2/mdt.c index 47dd815433fd..e1c6777931b7 100644 --- a/fs/nilfs2/mdt.c +++ b/fs/nilfs2/mdt.c @@ -77,19 +77,22 @@ static int nilfs_mdt_create_block(struct inode *inode, unsigned long block, void *)) { struct the_nilfs *nilfs = NILFS_MDT(inode)->mi_nilfs; - struct nilfs_sb_info *writer = NULL; struct super_block *sb = inode->i_sb; struct nilfs_transaction_info ti; struct buffer_head *bh; int err; if (!sb) { - writer = nilfs_get_writer(nilfs); - if (!writer) { + /* + * Make sure this function is not called from any + * read-only context. + */ + if (!nilfs->ns_writer) { + WARN_ON(1); err = -EROFS; goto out; } - sb = writer->s_super; + sb = nilfs->ns_writer->s_super; } nilfs_transaction_begin(sb, &ti, 0); @@ -127,8 +130,6 @@ static int nilfs_mdt_create_block(struct inode *inode, unsigned long block, err = nilfs_transaction_commit(sb); else nilfs_transaction_abort(sb); - if (writer) - nilfs_put_writer(nilfs); out: return err; } -- cgit v1.2.3 From 843382370ec614768ac13582405f93635cf3637c Mon Sep 17 00:00:00 2001 From: Ryusuke Konishi Date: Tue, 5 May 2009 21:52:06 +0900 Subject: nilfs2: ensure to clear dirty state when deleting metadata file block This would fix the following failure during GC: nilfs_cpfile_delete_checkpoints: cannot delete block NILFS: GC failed during preparation: cannot delete checkpoints: err=-2 The problem was caused by a break in state consistency between page cache and btree; the above block was removed from the btree but the page buffering the block was remaining in the page cache in dirty state. This resolves the inconsistency by ensuring to clear dirty state of the page buffering the deleted block. Reported-by: David Arendt Signed-off-by: Ryusuke Konishi --- fs/nilfs2/mdt.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'fs/nilfs2/mdt.c') diff --git a/fs/nilfs2/mdt.c b/fs/nilfs2/mdt.c index e1c6777931b7..bb78745a0e30 100644 --- a/fs/nilfs2/mdt.c +++ b/fs/nilfs2/mdt.c @@ -300,7 +300,7 @@ int nilfs_mdt_delete_block(struct inode *inode, unsigned long block) int err; err = nilfs_bmap_delete(ii->i_bmap, block); - if (likely(!err)) { + if (!err || err == -ENOENT) { nilfs_mdt_mark_dirty(inode); nilfs_mdt_forget_block(inode, block); } -- cgit v1.2.3