linux/arch/alpha
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 alpha: Replace strncmp with str_has_prefix 2020-06-12 17:43:17 -07:00
configs Char/Misc driver patches for 5.7-rc1 2020-04-03 13:22:40 -07:00
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
lib saner calling conventions for csum_and_copy_..._user() 2020-08-20 15:45:15 -04:00
math-emu treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
mm mm/alpha: use general page fault accounting 2020-08-12 10:58:03 -07:00
oprofile smp: Remove smp_call_function() and on_each_cpu() return values 2019-06-23 14:26:26 +02:00
Kconfig dma-mapping: make support for dma ops optional 2020-07-19 09:29:23 +02:00
Kconfig.debug treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Makefile kconfig: make arch/*/configs/defconfig the default of KBUILD_DEFCONFIG 2019-06-09 15:08:18 +09:00