From b5ce1d83a62fc109d8e815b1fc71dcdb0d26bc49 Mon Sep 17 00:00:00 2001 From: Yoshihisa Abe Date: Mon, 25 Oct 2010 02:03:44 -0400 Subject: Coda: add spin lock to protect accesses to struct coda_inode_info. We mostly need it to protect cached user permissions. The c_flags field is advisory, reading the wrong value is harmless and in the worst case we hit a slow path where we have to make an extra upcall to the userspace cache manager when revalidating a dentry or inode. Signed-off-by: Yoshihisa Abe Signed-off-by: Jan Harkes Signed-off-by: Linus Torvalds --- fs/coda/dir.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'fs/coda/dir.c') diff --git a/fs/coda/dir.c b/fs/coda/dir.c index ccd98b0f2b0b..69fbbea75f1b 100644 --- a/fs/coda/dir.c +++ b/fs/coda/dir.c @@ -18,6 +18,7 @@ #include #include #include +#include #include @@ -617,7 +618,9 @@ static int coda_dentry_revalidate(struct dentry *de, struct nameidata *nd) goto out; /* clear the flags. */ + spin_lock(&cii->c_lock); cii->c_flags &= ~(C_VATTR | C_PURGE | C_FLUSH); + spin_unlock(&cii->c_lock); bad: unlock_kernel(); @@ -691,7 +694,10 @@ int coda_revalidate_inode(struct dentry *dentry) goto return_bad; coda_flag_inode_children(inode, C_FLUSH); + + spin_lock(&cii->c_lock); cii->c_flags &= ~(C_VATTR | C_PURGE | C_FLUSH); + spin_unlock(&cii->c_lock); } ok: -- cgit v1.2.3