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 --- include/linux/coda_fs_i.h | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) (limited to 'include/linux/coda_fs_i.h') diff --git a/include/linux/coda_fs_i.h b/include/linux/coda_fs_i.h index b3ef0c461578..e35071b1de0e 100644 --- a/include/linux/coda_fs_i.h +++ b/include/linux/coda_fs_i.h @@ -10,19 +10,24 @@ #include #include +#include #include /* * coda fs inode data + * c_lock protects accesses to c_flags, c_mapcount, c_cached_epoch, c_uid and + * c_cached_perm. + * vfs_inode is set only when the inode is created and never changes. + * c_fid is set when the inode is created and should be considered immutable. */ struct coda_inode_info { - struct CodaFid c_fid; /* Coda identifier */ - u_short c_flags; /* flags (see below) */ - struct list_head c_cilist; /* list of all coda inodes */ + struct CodaFid c_fid; /* Coda identifier */ + u_short c_flags; /* flags (see below) */ unsigned int c_mapcount; /* nr of times this inode is mapped */ unsigned int c_cached_epoch; /* epoch for cached permissions */ vuid_t c_uid; /* fsuid for cached permissions */ - unsigned int c_cached_perm; /* cached access permissions */ + unsigned int c_cached_perm; /* cached access permissions */ + spinlock_t c_lock; struct inode vfs_inode; }; -- cgit v1.2.1