linux/arch/powerpc
Al Viro c693cc4676 saner calling conventions for csum_and_copy_..._user()
All callers of these primitives will
	* discard anything we might've copied in case of error
	* ignore the csum value in case of error
	* always pass 0xffffffff as the initial sum, so the
resulting csum value (in case of success, that is) will never be 0.

That suggest the following calling conventions:
	* don't pass err_ptr - just return 0 on error.
	* don't bother with zeroing destination, etc. in case of error
	* don't pass the initial sum - just use 0xffffffff.

This commit does the minimal conversion in the instances of csum_and_copy_...();
the changes of actual asm code behind them are done later in the series.
Note that this asm code is often shared with csum_partial_copy_nocheck();
the difference is that csum_partial_copy_nocheck() passes 0 for initial
sum while csum_and_copy_..._user() pass 0xffffffff.  Fortunately, we are
free to pass 0xffffffff in all cases and subsequent patches will use that
freedom without any special comments.

A part that could be split off: parisc and uml/i386 claimed to have
csum_and_copy_to_user() instances of their own, but those were identical
to the generic one, so we simply drop them.  Not sure if it's worth
a separate commit...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-08-20 15:45:15 -04:00
..
boot Kbuild updates for v5.9 2020-08-09 14:10:26 -07:00
configs powerpc/configs: Add BLK_DEV_NVME to pseries_defconfig 2020-07-29 23:47:53 +10:00
crypto powerpc: Replace HTTP links with HTTPS ones 2020-07-22 00:01:23 +10:00
include saner calling conventions for csum_and_copy_..._user() 2020-08-20 15:45:15 -04:00
kernel iomap: constify ioreadX() iomem argument (as in generic implementation) 2020-08-14 19:56:57 -07:00
kexec powerpc/kexec_file: Enable early kernel OPAL calls 2020-07-29 23:47:55 +10:00
kvm PPC KVM update for 5.9 2020-08-09 13:24:02 -04:00
lib saner calling conventions for csum_and_copy_..._user() 2020-08-20 15:45:15 -04:00
math-emu
mm powerpc fixes for 5.9 #2 2020-08-14 13:40:27 -07:00
net powerpc/ppc-opcode: Consolidate powerpc instructions from bpf_jit.h 2020-07-16 13:12:42 +10:00
oprofile maccess: rename probe_user_{read,write} to copy_{from,to}_user_nofault 2020-06-17 10:57:41 -07:00
perf powerpc updates for 5.9 2020-08-07 10:33:50 -07:00
platforms Kbuild updates for v5.9 2020-08-09 14:10:26 -07:00
purgatory powerpc/kexec_file: Enable early kernel OPAL calls 2020-07-29 23:47:55 +10:00
sysdev powerpc: fix function annotations to avoid section mismatch warnings with gcc-10 2020-07-30 10:50:07 +10:00
tools powerpc/64s: allow for clang's objdump differences 2020-07-27 00:01:29 +10:00
xmon Kbuild updates for v5.9 2020-08-09 14:10:26 -07:00
Kbuild
Kconfig powerpc updates for 5.9 2020-08-07 10:33:50 -07:00
Kconfig.debug powerpc: Remove Xilinx PPC405/PPC440 support 2020-05-28 23:24:34 +10:00
Makefile powerpc/4xx: ppc4xx compile flag optimizations 2020-06-22 14:19:12 +10:00
Makefile.postlink