> Another thing apart speed issues is that this might confuse applications
> which assume that say sys_readdir() gives canonical names? Or, maybe more
> important, assumes that they never change. With this solution the name
> passed back might be different from case to case.
tar made on a DOS filesystem might get confused? It stores filenames as
they come, and if someone wants to extract a certain file, based on the
name just being seen, it wont work. (well, if this is a problem)
even if nothing breaks by some miracle :), it's a quality of
implementation issue i think.
What about the following solution to the 'alias names' problem:
- an optional per-filesystem 'import_string_from_user()' operation. This
would copy&translate name strings to a canonical form. On most CPUs this
would be nicely pipelined and thus the translation cost would be almost
zero. [we always copy from user-space first anyway]
So we always have an 'internal representation' that fits everything. The
dentry code knows nothing about this alias problem. No complexity in the
lookup itself. [Also, we could use an 'export' function too, for symbolic
links? unsure.]
-- mingo