ALSA: mixart: Replace with __packed attribute

Replace the old __attribute__((packed)) with the new __packed.
Only cleanup, no functional changes.

Link: https://lore.kernel.org/r/20231025132314.5878-6-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: mixart: Replace one-element arrays with simple object declarations

One-element arrays are deprecated, and we are replacing them with flexible
array members instead. However, in this case it seems those one-element
arrays have never actually been used as fake flexible arrays.

See this code that dates from Linux-2.6.12-rc2 initial git repository build
(commit 1da177e4c3f4 ("Linux-2.6.12-rc2")):

sound/pci/mixart/mixart_core.h:
215 struct mixart_stream_state_req
216 {
217 u32 delayed;
218 u64 scheduler;
219 u32 reserved4np[3];
220 u32 stream_count; /* set to 1 for instance */
221 struct mixart_flow_info stream_info; /* could be an array[stream_count] */
222 } __attribute__((packed));

sound/pci/mixart/mixart.c:
388
389 memset(&stream_state_req, 0, sizeof(stream_state_req));
390 stream_state_req.stream_count = 1;
391 stream_state_req.stream_info.stream_desc.uid_pipe = stream->pipe->group_uid;
392 stream_state_req.stream_info.stream_desc.stream_idx = stream->substream->number;
393

So, taking the code above as example, replace multiple one-element
arrays with simple object declarations, and refactor the rest of the
code, accordingly.

This helps with the ongoing efforts to tighten the FORTIFY_SOURCE
routines on memcpy() and help us make progress towards globally
enabling -fstrict-flex-arrays=3 [1].

This results in no differences in binary output.

Link: https://github.com/KSPP/linux/issues/79
Link: https://github.com/KSPP/linux/issues/296
Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1]
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/ZGfiFjcL8+r3mayq@work
Signed-off-by: Takashi Iwai <tiwai@suse.de>

ALSA: mixart: Reduce size of mixart_timer_notify

The mixart_timer_notify structure was larger than could be represented
by the mixart_msg_data array storage. Adjust the size to as large as
possible to fix the warning seen with -Warray-bounds builds:

sound/pci/mixart/mixart_core.c: In function 'snd_mixart_threaded_irq':
sound/pci/mixart/mixart_core.c:447:50: error: array subscript 'struct mixart_timer_notify[0]' is partly outside array bounds of 'u32[128]' {aka 'unsigned int[128]'} [-Werror=array-bounds]
447 | for(i=0; i<notify->stream_count; i++) {
| ^~
sound/pci/mixart/mixart_core.c:328:12: note: while referencing 'mixart_msg_data'
328 | static u32 mixart_msg_data[MSG_DEFAULT_SIZE / 4];
| ^~~~~~~~~~~~~~~

Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20211207062941.2413679-1-keescook@chromium.org
Signed-off-by: Takashi Iwai <tiwai@suse.de>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

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 this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details you
should have received a copy of the gnu general public license along
with this program if not write to the free software foundation inc
59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ALSA: mixart: Use nonatomic PCM ops

Like the previous patch for VX boards, miXart device driver can be
also rewritten to use nonatomic PCM ops. Simply spinlocks are
replaced with mutex, the tasklet code is merged into the threaded irq
handler. Also, now mgr->msg_mutex is superfluous, so merged to
msg_lock.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

IRQ: Maintain regs pointer globally rather than passing to IRQ handlers

Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.

(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.

(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)

[ALSA] Remove xxx_t typedefs: PCI miXart

Modules: MIXART driver

Remove xxx_t typedefs from the PCI miXart driver.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!