linux/sound/core/timer_compat.c
Takashi Iwai beb45974dd ALSA: timer: Use guard() for locking
We can simplify the code gracefully with new guard() macro and co for
automatic cleanup of locks.

For making changes easier, some functions widen the application of
register_mutex, but those shouldn't influence on any actual
performance.

Also, one code block was factored out as a function so that guard()
can be applied cleanly without much indentation.

There are still a few remaining explicit spin_lock/unlock calls, and
those are for the places where we do temporary unlock/relock, which
doesn't fit well with the guard(), so far.

Only the code refactoring, and no functional changes.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20240227085306.9764-4-tiwai@suse.de
2024-02-28 15:01:20 +01:00

122 lines
3.5 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* 32bit -> 64bit ioctl wrapper for timer API
* Copyright (c) by Takashi Iwai <tiwai@suse.de>
*/
/* This file included from timer.c */
#include <linux/compat.h>
/*
* ILP32/LP64 has different size for 'long' type. Additionally, the size
* of storage alignment differs depending on architectures. Here, '__packed'
* qualifier is used so that the size of this structure is multiple of 4 and
* it fits to any architectures with 32 bit storage alignment.
*/
struct snd_timer_gparams32 {
struct snd_timer_id tid;
u32 period_num;
u32 period_den;
unsigned char reserved[32];
} __packed;
struct snd_timer_info32 {
u32 flags;
s32 card;
unsigned char id[64];
unsigned char name[80];
u32 reserved0;
u32 resolution;
unsigned char reserved[64];
};
static int snd_timer_user_gparams_compat(struct file *file,
struct snd_timer_gparams32 __user *user)
{
struct snd_timer_gparams gparams;
if (copy_from_user(&gparams.tid, &user->tid, sizeof(gparams.tid)) ||
get_user(gparams.period_num, &user->period_num) ||
get_user(gparams.period_den, &user->period_den))
return -EFAULT;
return timer_set_gparams(&gparams);
}
static int snd_timer_user_info_compat(struct file *file,
struct snd_timer_info32 __user *_info)
{
struct snd_timer_user *tu;
struct snd_timer_info32 info;
struct snd_timer *t;
tu = file->private_data;
if (!tu->timeri)
return -EBADFD;
t = tu->timeri->timer;
if (!t)
return -EBADFD;
memset(&info, 0, sizeof(info));
info.card = t->card ? t->card->number : -1;
if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
info.flags |= SNDRV_TIMER_FLG_SLAVE;
strscpy(info.id, t->id, sizeof(info.id));
strscpy(info.name, t->name, sizeof(info.name));
info.resolution = t->hw.resolution;
if (copy_to_user(_info, &info, sizeof(*_info)))
return -EFAULT;
return 0;
}
enum {
SNDRV_TIMER_IOCTL_GPARAMS32 = _IOW('T', 0x04, struct snd_timer_gparams32),
SNDRV_TIMER_IOCTL_INFO32 = _IOR('T', 0x11, struct snd_timer_info32),
SNDRV_TIMER_IOCTL_STATUS_COMPAT32 = _IOW('T', 0x14, struct snd_timer_status32),
SNDRV_TIMER_IOCTL_STATUS_COMPAT64 = _IOW('T', 0x14, struct snd_timer_status64),
};
static long __snd_timer_user_ioctl_compat(struct file *file, unsigned int cmd,
unsigned long arg)
{
void __user *argp = compat_ptr(arg);
switch (cmd) {
case SNDRV_TIMER_IOCTL_PVERSION:
case SNDRV_TIMER_IOCTL_TREAD_OLD:
case SNDRV_TIMER_IOCTL_TREAD64:
case SNDRV_TIMER_IOCTL_GINFO:
case SNDRV_TIMER_IOCTL_GSTATUS:
case SNDRV_TIMER_IOCTL_SELECT:
case SNDRV_TIMER_IOCTL_PARAMS:
case SNDRV_TIMER_IOCTL_START:
case SNDRV_TIMER_IOCTL_START_OLD:
case SNDRV_TIMER_IOCTL_STOP:
case SNDRV_TIMER_IOCTL_STOP_OLD:
case SNDRV_TIMER_IOCTL_CONTINUE:
case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
case SNDRV_TIMER_IOCTL_PAUSE:
case SNDRV_TIMER_IOCTL_PAUSE_OLD:
case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
return __snd_timer_user_ioctl(file, cmd, (unsigned long)argp, true);
case SNDRV_TIMER_IOCTL_GPARAMS32:
return snd_timer_user_gparams_compat(file, argp);
case SNDRV_TIMER_IOCTL_INFO32:
return snd_timer_user_info_compat(file, argp);
case SNDRV_TIMER_IOCTL_STATUS_COMPAT32:
return snd_timer_user_status32(file, argp);
case SNDRV_TIMER_IOCTL_STATUS_COMPAT64:
return snd_timer_user_status64(file, argp);
}
return -ENOIOCTLCMD;
}
static long snd_timer_user_ioctl_compat(struct file *file, unsigned int cmd,
unsigned long arg)
{
struct snd_timer_user *tu = file->private_data;
guard(mutex)(&tu->ioctl_lock);
return __snd_timer_user_ioctl_compat(file, cmd, arg);
}