On Sat, May 24, 2008 at 05:47:15PM -0600, Vadim Klishko wrote: > On Friday, May 23, 2008 5:01 PM, "Greg KH" wrote: > > > On Fri, May 23, 2008 at 04:42:41PM -0600, Vadim Klishko wrote: > >> On Friday, May 23, 2008 4:00 PM, "Greg KH" wrote: > >> > >> > On Fri, May 23, 2008 at 02:32:46PM -0600, Vadim Klishko wrote: > >> >> Hello Everybody, > >> >> > >> >> Could anyone please tell me what functions I could call from a Linux kernel module to: > >> >> > >> >> 1) dynamically load a library, > >> > > >> > None. > >> > > >> >> 2) get the address of an exported function, > >> > > >> > None. > >> > > >> >> 3) unload the library? > >> > > >> > None. > >> > > >> > None of these things are things that you should do from within a kernel > >> > module. > >> > > > First of all, I want to thank all those who answered for their > suggestions. > > Second of all, I suspect my question about loading a library within a > kernel module may have been misunderstood. I am not talking about > loading a user-space library. I am talking about loading my own > library written specifically to be used in kernel space. The kernel does not have "libraries", it allows the loading of kernel "modules" at any time though. > The idea is that the library is optional. If it is found on the > system, then it is used. If it is not present, the module uses its > internal, simpler algorithm. Any suggestions? Just use the existing module loading functions to attempt to load your module, if present. But I would wonder why you would make such a thing "optional" at all? Either you need it or you do not, there should not be a real issue here. > >> >> Also, what are the functions that would allow me to read from and > >> >> write to a binary or text file from within a kernel module? > >> > > >> > None, this is not what a kernel module should ever be doing. > >> > > >> > Let's turn it around the other way, what are you trying to achieve that > >> > makes you think the above things are necessary to do? > >> > > >> By reading a file, I am trying to load a system-wide device > >> configuration. Of course, it could be hard-coded into the module, but > >> why not try having it adjustable? > > > > It's fine to be configurable, that's wonderful and something we do all > > the time. > > > > But it is userspace sending the data into the kernel driver, not the > > other way around. With the plethera of different filesystems, mount > > points, boot sequences, namespaces and the like, the kernel can not > > specific a single location of a config file and have it work with all > > systems. > > > > So have a startup script that parses the config file in userspace and > > then writes the needed info into the driver using sysfs, or better yet, > > configfs (which is sounds like what you need to use here.) > > That would work. How do I read and write settings using configfs? See the configfs documentation in the kernel tree :) thanks, greg k-h
