orangefs: reorganize setattr functions to track attribute changes

OrangeFS accepts a mask indicating which attributes were changed.  The
kernel must not set any bits except those that were actually changed.
The kernel must set the uid/gid of the request to the actual uid/gid
responsible for the change.

Code path for notify_change initiated setattrs is

orangefs_setattr(dentry, iattr)
-> __orangefs_setattr(inode, iattr)

In kernel changes are initiated by calling __orangefs_setattr.

Code path for writeback is

orangefs_write_inode
-> orangefs_inode_setattr

attr_valid and attr_uid and attr_gid change together under i_lock.
I_DIRTY changes separately.

__orangefs_setattr
	lock
	if needs to be cleaned first, unlock and retry
	set attr_valid
	copy data in
	unlock
	mark_inode_dirty

orangefs_inode_setattr
	lock
	copy attributes out
	unlock
	clear getattr_time
	# __writeback_single_inode clears dirty

orangefs_inode_getattr
	# possible to get here with attr_valid set and not dirty
	lock
	if getattr_time ok or attr_valid set, unlock and return
	unlock
	do server operation
	# another thread may getattr or setattr, so check for that
	lock
	if getattr_time ok or attr_valid, unlock and return
	else, copy in
	update getattr_time
	unlock

Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>

1 files changed, 6 insertions, 2 deletions

diff --git a/fs/orangefs/orangefs-kernel.h b/fs/orangefs/orangefs-kernel.h
index 4f0cf14c18f6..a74d9e8c5f9e 100644
--- a/fs/orangefs/orangefs-kernel.h
+++ b/fs/orangefs/orangefs-kernel.h
@@ -193,6 +193,9 @@ struct orangefs_inode_s {
 	sector_t last_failed_block_index_read;
 
 	unsigned long getattr_time;
+	int attr_valid;
+	kuid_t attr_uid;
+	kgid_t attr_gid;
 
 	DECLARE_HASHTABLE(xattr_cache, 4);
 };
@@ -345,7 +348,8 @@ struct inode *orangefs_new_inode(struct super_block *sb,
 			      dev_t dev,
 			      struct orangefs_object_kref *ref);
 
-int orangefs_setattr(struct dentry *dentry, struct iattr *iattr);
+int __orangefs_setattr(struct inode *, struct iattr *);
+int orangefs_setattr(struct dentry *, struct iattr *);
 
 int orangefs_getattr(const struct path *path, struct kstat *stat,
 		     u32 request_mask, unsigned int flags);
@@ -403,7 +407,7 @@ int orangefs_inode_getattr(struct inode *, int);
 
 int orangefs_inode_check_changed(struct inode *inode);
 
-int orangefs_inode_setattr(struct inode *inode, struct iattr *iattr);
+int orangefs_inode_setattr(struct inode *inode);
 
 bool orangefs_cancel_op_in_progress(struct orangefs_kernel_op_s *op);