powerpc: replace #include <asm/export.h> with #include <linux/export.h>

Commit ddb5cdbafaaa ("kbuild: generate KSYMTAB entries by modpost")
deprecated <asm/export.h>, which is now a wrapper of <linux/export.h>.

Replace #include <asm/export.h> with #include <linux/export.h>.

After all the <asm/export.h> lines are converted, <asm/export.h> and
<asm-generic/export.h> will be removed.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
[mpe: Fixup selftests that stub asm/export.h]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230806150954.394189-2-masahiroy@kernel.org

ppc: propagate the calling conventions change down to csum_partial_copy_generic()

... and get rid of the pointless fallback in the wrappers. On error it used
to zero the unwritten area and calculate the csum of the entire thing. Not
wanting to do it in assembler part had been very reasonable; doing that in
the first place, OTOH... In case of an error the caller discards the data
we'd copied, along with whatever checksum it might've had.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

powerpc: fix csum_ipv6_magic() on little endian platforms

On little endian platforms, csum_ipv6_magic() keeps len and proto in
CPU byte order. This generates a bad results leading to ICMPv6 packets
from other hosts being dropped by powerpc64le platforms.

In order to fix this, len and proto should be converted to network
byte order ie bigendian byte order. However checksumming 0x12345678
and 0x56341278 provide the exact same result so it is enough to
rotate the sum of len and proto by 1 byte.

PPC32 only support bigendian so the fix is needed for PPC64 only

Fixes: e9c4943a107b ("powerpc: Implement csum_ipv6_magic in assembly")
Reported-by: Jianlin Shi <jishi@redhat.com>
Reported-by: Xin Long <lucien.xin@gmail.com>
Cc: <stable@vger.kernel.org> # 4.18+
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Tested-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc: Implement csum_ipv6_magic in assembly

The generic csum_ipv6_magic() generates a pretty bad result

00000000 <csum_ipv6_magic>: (PPC32)
0: 81 23 00 00 lwz r9,0(r3)
4: 81 03 00 04 lwz r8,4(r3)
8: 7c e7 4a 14 add r7,r7,r9
c: 7d 29 38 10 subfc r9,r9,r7
10: 7d 4a 51 10 subfe r10,r10,r10
14: 7d 27 42 14 add r9,r7,r8
18: 7d 2a 48 50 subf r9,r10,r9
1c: 80 e3 00 08 lwz r7,8(r3)
20: 7d 08 48 10 subfc r8,r8,r9
24: 7d 4a 51 10 subfe r10,r10,r10
28: 7d 29 3a 14 add r9,r9,r7
2c: 81 03 00 0c lwz r8,12(r3)
30: 7d 2a 48 50 subf r9,r10,r9
34: 7c e7 48 10 subfc r7,r7,r9
38: 7d 4a 51 10 subfe r10,r10,r10
3c: 7d 29 42 14 add r9,r9,r8
40: 7d 2a 48 50 subf r9,r10,r9
44: 80 e4 00 00 lwz r7,0(r4)
48: 7d 08 48 10 subfc r8,r8,r9
4c: 7d 4a 51 10 subfe r10,r10,r10
50: 7d 29 3a 14 add r9,r9,r7
54: 7d 2a 48 50 subf r9,r10,r9
58: 81 04 00 04 lwz r8,4(r4)
5c: 7c e7 48 10 subfc r7,r7,r9
60: 7d 4a 51 10 subfe r10,r10,r10
64: 7d 29 42 14 add r9,r9,r8
68: 7d 2a 48 50 subf r9,r10,r9
6c: 80 e4 00 08 lwz r7,8(r4)
70: 7d 08 48 10 subfc r8,r8,r9
74: 7d 4a 51 10 subfe r10,r10,r10
78: 7d 29 3a 14 add r9,r9,r7
7c: 7d 2a 48 50 subf r9,r10,r9
80: 81 04 00 0c lwz r8,12(r4)
84: 7c e7 48 10 subfc r7,r7,r9
88: 7d 4a 51 10 subfe r10,r10,r10
8c: 7d 29 42 14 add r9,r9,r8
90: 7d 2a 48 50 subf r9,r10,r9
94: 7d 08 48 10 subfc r8,r8,r9
98: 7d 4a 51 10 subfe r10,r10,r10
9c: 7d 29 2a 14 add r9,r9,r5
a0: 7d 2a 48 50 subf r9,r10,r9
a4: 7c a5 48 10 subfc r5,r5,r9
a8: 7c 63 19 10 subfe r3,r3,r3
ac: 7d 29 32 14 add r9,r9,r6
b0: 7d 23 48 50 subf r9,r3,r9
b4: 7c c6 48 10 subfc r6,r6,r9
b8: 7c 63 19 10 subfe r3,r3,r3
bc: 7c 63 48 50 subf r3,r3,r9
c0: 54 6a 80 3e rotlwi r10,r3,16
c4: 7c 63 52 14 add r3,r3,r10
c8: 7c 63 18 f8 not r3,r3
cc: 54 63 84 3e rlwinm r3,r3,16,16,31
d0: 4e 80 00 20 blr

0000000000000000 <.csum_ipv6_magic>: (PPC64)
0: 81 23 00 00 lwz r9,0(r3)
4: 80 03 00 04 lwz r0,4(r3)
8: 81 63 00 08 lwz r11,8(r3)
c: 7c e7 4a 14 add r7,r7,r9
10: 7f 89 38 40 cmplw cr7,r9,r7
14: 7d 47 02 14 add r10,r7,r0
18: 7d 30 10 26 mfocrf r9,1
1c: 55 29 f7 fe rlwinm r9,r9,30,31,31
20: 7d 4a 4a 14 add r10,r10,r9
24: 7f 80 50 40 cmplw cr7,r0,r10
28: 7d 2a 5a 14 add r9,r10,r11
2c: 80 03 00 0c lwz r0,12(r3)
30: 81 44 00 00 lwz r10,0(r4)
34: 7d 10 10 26 mfocrf r8,1
38: 55 08 f7 fe rlwinm r8,r8,30,31,31
3c: 7d 29 42 14 add r9,r9,r8
40: 81 04 00 04 lwz r8,4(r4)
44: 7f 8b 48 40 cmplw cr7,r11,r9
48: 7d 29 02 14 add r9,r9,r0
4c: 7d 70 10 26 mfocrf r11,1
50: 55 6b f7 fe rlwinm r11,r11,30,31,31
54: 7d 29 5a 14 add r9,r9,r11
58: 7f 80 48 40 cmplw cr7,r0,r9
5c: 7d 29 52 14 add r9,r9,r10
60: 7c 10 10 26 mfocrf r0,1
64: 54 00 f7 fe rlwinm r0,r0,30,31,31
68: 7d 69 02 14 add r11,r9,r0
6c: 7f 8a 58 40 cmplw cr7,r10,r11
70: 7c 0b 42 14 add r0,r11,r8
74: 81 44 00 08 lwz r10,8(r4)
78: 7c f0 10 26 mfocrf r7,1
7c: 54 e7 f7 fe rlwinm r7,r7,30,31,31
80: 7c 00 3a 14 add r0,r0,r7
84: 7f 88 00 40 cmplw cr7,r8,r0
88: 7d 20 52 14 add r9,r0,r10
8c: 80 04 00 0c lwz r0,12(r4)
90: 7d 70 10 26 mfocrf r11,1
94: 55 6b f7 fe rlwinm r11,r11,30,31,31
98: 7d 29 5a 14 add r9,r9,r11
9c: 7f 8a 48 40 cmplw cr7,r10,r9
a0: 7d 29 02 14 add r9,r9,r0
a4: 7d 70 10 26 mfocrf r11,1
a8: 55 6b f7 fe rlwinm r11,r11,30,31,31
ac: 7d 29 5a 14 add r9,r9,r11
b0: 7f 80 48 40 cmplw cr7,r0,r9
b4: 7d 29 2a 14 add r9,r9,r5
b8: 7c 10 10 26 mfocrf r0,1
bc: 54 00 f7 fe rlwinm r0,r0,30,31,31
c0: 7d 29 02 14 add r9,r9,r0
c4: 7f 85 48 40 cmplw cr7,r5,r9
c8: 7c 09 32 14 add r0,r9,r6
cc: 7d 50 10 26 mfocrf r10,1
d0: 55 4a f7 fe rlwinm r10,r10,30,31,31
d4: 7c 00 52 14 add r0,r0,r10
d8: 7f 80 30 40 cmplw cr7,r0,r6
dc: 7d 30 10 26 mfocrf r9,1
e0: 55 29 ef fe rlwinm r9,r9,29,31,31
e4: 7c 09 02 14 add r0,r9,r0
e8: 54 03 80 3e rotlwi r3,r0,16
ec: 7c 03 02 14 add r0,r3,r0
f0: 7c 03 00 f8 not r3,r0
f4: 78 63 84 22 rldicl r3,r3,48,48
f8: 4e 80 00 20 blr

This patch implements it in assembly for both PPC32 and PPC64

Link: https://github.com/linuxppc/linux/issues/9
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/64: Use optimized checksum routines on little-endian

Currently we have optimized hand-coded assembly checksum routines for
big-endian 64-bit systems, but for little-endian we use the generic C
routines. This modifies the optimized routines to work for
little-endian. With this, we no longer need to enable
CONFIG_GENERIC_CSUM. This also fixes a couple of comments in
checksum_64.S so they accurately reflect what the associated instruction
does.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
[mpe: Use the more common __BIG_ENDIAN__]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc: EX_TABLE macro for exception tables

This macro is taken from s390, and allows more flexibility in
changing exception table format.

mpe: Put it in ppc_asm.h and only define one version using
stringinfy_in_c(). Add some empty definitions and headers to keep the
selftests happy.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

ppc: move exports to definitions

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

powerpc/lib: Clarify that adde is an instruction and we mean plural

Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc: optimise csum_partial() call when len is constant

csum_partial is often called for small fixed length packets
for which it is suboptimal to use the generic csum_partial()
function.

For instance, in my configuration, I got:
* One place calling it with constant len 4
* Seven places calling it with constant len 8
* Three places calling it with constant len 14
* One place calling it with constant len 20
* One place calling it with constant len 24
* One place calling it with constant len 32

This patch renames csum_partial() to __csum_partial() and
implements csum_partial() as a wrapper inline function which
* uses csum_add() for small 16bits multiple constant length
* uses ip_fast_csum() for other 32bits multiple constant
* uses __csum_partial() in all other cases

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>

powerpc: inline ip_fast_csum()

In several architectures, ip_fast_csum() is inlined
There are functions like ip_send_check() which do nothing
much more than calling ip_fast_csum().
Inlining ip_fast_csum() allows the compiler to optimise better

Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[scottwood: whitespace and cast fixes]
Signed-off-by: Scott Wood <oss@buserror.net>

powerpc: put csum_tcpudp_magic inline

csum_tcpudp_magic() is only a few instructions, and does modify
really few registers. So it is not worth having it as a separate
function and suffer function branching and saving of volatile
registers.

This patch makes it inline by use of the already existing
csum_tcpudp_nofold() function.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <scottwood@freescale.com>

powerpc: Restore registers on error exit from csum_partial_copy_generic()

The csum_partial_copy_generic() function saves the PowerPC non-volatile
r14, r15, and r16 registers for the main checksum-and-copy loop.
Unfortunately, it fails to restore them upon error exit from this loop,
which results in silent corruption of these registers in the presumably
rare event of an access exception within that loop.

This commit therefore restores these register on error exit from the loop.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc: Fix parameter clobber in csum_partial_copy_generic()

The csum_partial_copy_generic() uses register r7 to adjust the remaining
bytes to process. Unfortunately, r7 also holds a parameter, namely the
address of the flag to set in case of access exceptions while reading
the source buffer. Lacking a quantum implementation of PowerPC, this
commit instead uses register r9 to do the adjusting, leaving r7's
pointer uncorrupted.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Anton Blanchard <anton@samba.org>
Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc: Merge STK_REG/PARAM/FRAMESIZE

Merge the defines of STACKFRAMESIZE, STK_REG, STK_PARAM from different
places.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc: Fix usage of register macros getting ready for %r0 change

Anything that uses a constructed instruction (ie. from ppc-opcode.h),
need to use the new R0 macro, as %r0 is not going to work.

Also convert usages of macros where we are just determining an offset
(usually for a load/store), like:
std r14,STK_REG(r14)(r1)
Can't use STK_REG(r14) as %r14 doesn't work in the STK_REG macro since
it's just calculating an offset.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc: Optimise 64bit csum_partial_copy_generic and add csum_and_copy_from_user

We use the same core loop as the new csum_partial, adding in the
stores and exception handling code. To keep things simple we do all the
exception fixup in csum_and_copy_from_user. This wrapper function is
modelled on the generic checksum code and is careful to always calculate
a complete checksum even if we only copied part of the data to userspace.

To test this I forced checksumming on over loopback and ran socklib (a
simple TCP benchmark). On a POWER6 575 throughput improved by 19% with
this patch. If I forced both the sender and receiver onto the same cpu
(with the hope of shifting the benchmark from being cache bandwidth limited
to cpu limited), adding this patch improved performance by 55%

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc: Optimise 64bit csum_partial

The main loop of csum_partial runs very slowly on recent POWER CPUs. After some
analysis on both POWER6 and POWER7 I came up with routine below. First we get
the source aligned to a double word, ignoring any odd alignment to keep things
simple. Then we do 64 bytes at a time, with an entry and exit limb of a further
64 bytes. On both POWER6 and POWER7 this should be as fast as we can go since
we are limited by the latency of the adde instructions.

To test this I forced checksumming on over loopback and ran socklib (a
simple TCP benchmark). On a POWER6 575 throughput improved by 11% with
this patch.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc: Rename files to have consistent _32/_64 suffixes

This doesn't change any code, just renames things so we consistently
have foo_32.c and foo_64.c where we have separate 32- and 64-bit
versions.

Signed-off-by: Paul Mackerras <paulus@samba.org>