proc_lookup not exported

Hi folks.

I noticed that proc_lookup is not exported in fs/proc/procfs_syms.c but that the function is an external in include/linux/proc_fs.h.

This patch exports the function appropriately and is against the 2.4.3 kernel tree.

*** procfs_syms.c.orig Tue Apr 17 15:50:56 2001
--- procfs_syms.c Tue Apr 17 15:51:19 2001
***************
*** 19,24 ****
--- 19,25 ----
EXPORT_SYMBOL(proc_net);
EXPORT_SYMBOL(proc_bus);
EXPORT_SYMBOL(proc_root_driver);
+ EXPORT_SYMBOL(proc_lookup);

static DECLARE_FSTYPE(proc_fs_type, "proc", proc_read_super,
FS_SINGLE);

-Jeff

Jeff Golds
[email protected]

Not every public function needs to be exported. proc_lookup() is shared between different files in fs/proc/, so it can't be made static. However, it got no business being used outside of the fs/proc and it certainly shouldn't be used in modules.

I don't see why not. I created my own mkdir and rmdir handlers in my module. I'd like to use the lookup function that proc supplies instead of supplying my own, why shouldn't I be allowed to do that? It's not as if I am doing something other than what normally happens: I am assigning inode_operations::lookup to be proc_lookup.

-Jeff

Jeff Golds
[email protected]

Use ramfs as a model; procfs is not well-suited for that sort of work.

I don't want to cause trouble, but it sure seems like the kernel source tree could be better organized. For example, in every C application I have seen, global header files specify interfaces into the relevant module and local header files are for intramodule use only. In the Linux kernel tree, ALL the header files are global, thus, you can't easily tell what things are exported and what is not as you can't just look at the header file. Isn't this against what open source is about:
Requiring inside knowledge about the code?

I don't understand why local header files are not used. It's easy to prevent people from using the wrong functions, simply make a script that checks to see if people are including the local header files from other modules and return an error if they are. This could be checked at build time.

Maybe this is all old news, I am rather new to the Linux kernel, but perhaps this is something that could be addressed in future (2.5?) versions of the kernel.

-Jeff

Jeff Golds
[email protected]