alloc/free quesion in ixp4xx driver

Phil Endecott
2007-05-17T15:51:52Z

Dear MTD experts,

I have been looking at the MTD ixp4xx driver
(drivers/mtd/maps/ixp4xx.c), mainly as an example of something that
uses the ixp4xx expansion bus, and I have a couple of questions. I
apologise for being a "newbie" on this subject, I have not written a
lot of kernel code.

- In ixp4xx_flash_probe(), a struct ixp4xx_flash_info in kalloc()ed.
Where is it freed?

- In ixp4xx_flash_remove() you have:
release_resource(info->res);
kfree(info->res);
In other places where release_resource() is called I do not see a
call to kfree(). Is this right?

Most likely, this is all OK and I need to learn more about how these
functions should be used. But my thought on seeing this was that the
kfree() should have been freeing info, not info->res.

I am also uncertain about release_resource() vs. release_mem_region().
Are they interchangeable?

I have been looking at 2.6.21, but a quick check at
http://git.infradead.org/?p=mtd-2.6.git;a=blob;f=drivers/mtd/maps/ixp4xx.c;h=7a828e3e6446d7f9254f083d3b02bb2e9e02e9e0;hb=HEAD
suggests that it is the same in your tree (if I have understood gitweb properly).

Many thanks,

Phil.

P.S. I'm subscribed to the digest, so if you Cc: me in your reply I'll
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