Re: 2.4 vs 2.6 versions of include/linux/ioport.h

From: Randy.Dunlap (rddunlap@osdl.org)
Date: Tue Aug 05 2003 - 09:57:58 EST


On Tue, 5 Aug 2003 10:41:08 -0400 Gene Heskett <gene.heskett@verizon.net> wrote:

| Greetings;
|
| In the 2.4 includes, find this in ioport.h
| ----
| /* Compatibility cruft */
| #define check_region(start,n) __check_region(&ioport_resource,
| (start), (n))
| [snip]
| extern int __check_region(struct resource *, unsigned long, unsigned
| long);
| ----
| But in the 2.6 version, find this:
| ----
| /* Compatibility cruft */
| [snip]
| extern int __check_region(struct resource *, unsigned long, unsigned
| long);
| [snip]
| static inline int __deprecated check_region(unsigned long s, unsigned
| long n)
| {
| return __check_region(&ioport_resource, s, n);
| }
| ----
| First, the define itself is missing in the 2.6 version.
|
| Many drivers seem to use this call, and in that which I'm trying to
| build, the nforce and advansys modules use it. And while the modules
| seem to build, they do not run properly.
|
| I cannot run 2.6.x for extended tests because of the advansys breakage
| this causes. I also haven't even tried to run X because of the
| nforce error reported when its built, the same error as attacks the
| advansys code.
|
| Can I ask why this change was made, and is there a suitable
| replacement call available that these drivers could use instead of
| check_region(), as shown here in a snip from advansys.c?
| ----
| if (check_region(iop, ASC_IOADR_GAP) != 0) {
| ...
| if (check_region(iop_base, ASC_IOADR_GAP) != 0) {
| ...
|
| Hopeing for some hints here.

check_region() was racy. Use request_region() instead.

   if (!request_region(iop, ASC_IOADR_GAP, "advansys")) {
   ...

   if (!request_region(iop_base, ASC_IOADR, "advansys")) {
   ...

Of course, if successful, this assigns the region to the driver,
while check_region() didn't do this, so release_region() should be
used as needed to return the resources.

--
~Randy
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Thu Aug 07 2003 - 22:00:29 EST