[syslinux] (no subject)

[H. Peter Anvin]

gabriele balducci wrote:
> 
> fails with:
> 
> ...
> gcc -Wp,-MT,extlinux.o,-MMD,.extlinux.o.d -W -Wall -Wno-sign-compare -D_FILE_OFFSET_BITS=64 -g -Os -I. -I.. -I../libfat -c -o extlinux.o extlinux.c
> extlinux.c: In function `get_size':
> extlinux.c:285: error: `BLKGETSIZE64' undeclared (first use in this function)
> extlinux.c:285: error: (Each undeclared identifier is reported only once
> extlinux.c:285: error: for each function it appears in.)
> make[2]: *** [extlinux.o] Error 1
> make[2]: Leaving directory `/home/balducci/tmp/install-us-d/syslinux/syslinux-3.01/extlinux'
> ...
> 
> As a matter of fact, I can't grep any BLKGETSIZE64 declaration under my
> /usr/include directory tree.
> 
> I guess this is due to the fact that my installed kernel headers are
> quite old (redhat-7.1, kernel 2.4.2).
> 

You're absolutely right.  The problem is that your glibc and associated 
headers are way too old.  You have quite an antique there.

> However, I keep my kernel up2date: I'm running kernel-2.6.10.
> 
> In order to make syslinux use the 2.6.10 headers, I unpack and configure
> a kernel-2.6.10 tree. Then, I try to build with:
> 
> C_INCLUDE_PATH=/home/balducci/tmp/install-us-d/syslinux/linux-2.6.10/include
> export C_INCLUDE_PATH
> make depend
> make installer

This doesn't work with 2.6 kernels.  You're supposed to use the 
kernel-derived headers that come with glibc, not the ones shipped with 
the kernel.  Personally I think this methodology is flawed, but that's 
the way it is.

> I seem to understand that the 2.6.10 headers are actually used, but
> something is going wrong any way. Trying to satisfy the use of
> GFP_KERNEL by including gfp.h (which contains the declaration) in
> extlinux.c produces other errors which I did not try to dig into.

Your best bet is to add:

#define BLKGETSIZE64 _IOR(0x12,114,size_t)

to extlinux.c.

	-hpa