Re: 2.6.19-rc2-mm1

Jiri Kosina
2006-10-18T23:04:51Z

On Thu, 19 Oct 2006, Jiri Kosina wrote:

> void i_size_write(struct inode *inode, loff_t i_size)
> {
> - WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
> + /* calling us without i_mutex is OK when not connected to dentry yet */
> + if (list_empty(&inode->i_dentry))
> + WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
> #if BITS_PER_LONG==32 && defined(CONFIG_SMP)
> write_seqcount_begin(&inode->i_size_seqcount);
> inode->i_size = i_size;
> diff --git a/fs/namei.c b/fs/namei.c

This if of course bogus, the one below should be better, sorry

[PATCH] Fix spurious warning in i_size_write

i_size_write() can be legitimately called without inode->i_mutex locked.
This is OK in cases when the inode has not been yet linked into
the parent dentry, so no race condition on i_size can occur.

Signed-off-by: Jiri Kosina <jikos@jikos.cz>

---

fs/inode.c | 4 +++-
1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/fs/inode.c b/fs/inode.c
index bb88835..11d8794 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1386,7 +1386,9 @@ void __init inode_init(unsigned long mem

void i_size_write(struct inode *inode, loff_t i_size)
{
- WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
+ /* calling us without i_mutex is OK when not connected to dentry yet */
+ if (!list_empty(&inode->i_dentry))
+ WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex));
#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
write_seqcount_begin(&inode->i_size_seqcount);
inode->i_size = i_size;

--
Jiri Kosina