From 621e155a3591962420eacdd39f6f0aa29ceb221e Mon Sep 17 00:00:00 2001 From: Nick Piggin Date: Fri, 7 Jan 2011 17:49:27 +1100 Subject: fs: change d_compare for rcu-walk Change d_compare so it may be called from lock-free RCU lookups. This does put significant restrictions on what may be done from the callback, however there don't seem to have been any problems with in-tree fses. If some strange use case pops up that _really_ cannot cope with the rcu-walk rules, we can just add new rcu-unaware callbacks, which would cause name lookup to drop out of rcu-walk mode. For in-tree filesystems, this is just a mechanical change. Signed-off-by: Nick Piggin --- include/linux/dcache.h | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) (limited to 'include/linux/dcache.h') diff --git a/include/linux/dcache.h b/include/linux/dcache.h index 6cdf4995c90..75a072bf2a3 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -134,7 +134,9 @@ enum dentry_d_lock_class struct dentry_operations { int (*d_revalidate)(struct dentry *, struct nameidata *); int (*d_hash)(struct dentry *, struct qstr *); - int (*d_compare)(struct dentry *, struct qstr *, struct qstr *); + int (*d_compare)(const struct dentry *, const struct inode *, + const struct dentry *, const struct inode *, + unsigned int, const char *, const struct qstr *); int (*d_delete)(const struct dentry *); void (*d_release)(struct dentry *); void (*d_iput)(struct dentry *, struct inode *); @@ -145,12 +147,8 @@ struct dentry_operations { * Locking rules for dentry_operations callbacks are to be found in * Documentation/filesystems/Locking. Keep it updated! * - * the dentry parameter passed to d_hash and d_compare is the parent - * directory of the entries to be compared. It is used in case these - * functions need any directory specific information for determining - * equivalency classes. Using the dentry itself might not work, as it - * might be a negative dentry which has no information associated with - * it. + * FUrther descriptions are found in Documentation/filesystems/vfs.txt. + * Keep it updated too! */ /* d_flags entries */ -- cgit v1.2.3