This is a first try to move readdir() to become an inode operation. This is

necessary for a VFS implementation of "something like union-mounts" where a

readdir() needs to read the directory contents of multiple directories.

Besides that the new interface is no longer giving the struct file to the

filesystem implementations anymore.
Comments, please?

Jan
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Hmm, are you sure there are no users which keep some per-struct-file

information for directories? File offset is one such obvious thing which

you've handled but actually filesystem with more complicated structure

of directory may remember some hints about where we really are, keep

some readahead information or so...
								Honza

--

Jan Kara <jack@suse.cz>

SuSE CR Labs

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For example, the ext3 filesystem, when it is supported hash tree, does

exactly this.  See ext3_htree_store_dirent() in fs/ext3/dir.c and

ext3_htree_fill_tree() in fs/ext3/namei.c.
So your patch would break ext3 htree support.
						- Ted

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The hfsplus code keeps some extra data in the ->private_data of directories,

although I've lost track of the exact benefit from not looking at the code

in some years. As I recall it was a performance enhancement due to the

fact that the data for all directories is effectively in a single file.

I believe it was easier to keep the current position as a structure

rather than just an offset and be careful about the tracking. The hfs

code is almost identical to the hfsplus code in this area.
	Brad Boyer

	flar@allandria.com
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