On Tue, 24 Oct 2017 21:24:58 +0200, Takashi Iwai wrote:

On Tue, 24 Oct 2017 17:34:58 +0200, Kees Cook wrote:

...

In preparation for unconditionally passing the struct timer_list pointer to all timer callbacks, switch to using the new timer_setup() and from_timer() to pass the timer pointer explicitly.

Cc: Jaroslav Kysela perex@perex.cz Cc: Takashi Iwai tiwai@suse.com Cc: Takashi Sakamoto o-takashi@sakamocchi.jp Cc: alsa-devel@alsa-project.org Signed-off-by: Kees Cook keescook@chromium.org

---

include/sound/sb.h | 1 + sound/isa/sb/emu8000_pcm.c | 6 +++--- sound/isa/sb/sb8_midi.c | 12 ++++++------ 3 files changed, 10 insertions(+), 9 deletions(-)

diff --git a/include/sound/sb.h b/include/sound/sb.h index bacefaee411a..4aef395189ec 100644 --- a/include/sound/sb.h +++ b/include/sound/sb.h @@ -83,6 +83,7 @@ struct snd_sb { unsigned int playback_format; unsigned int capture_format; struct timer_list midi_timer;

• struct snd_rawmidi_substream *timer_substream;

This is superfluous. It's identical with chip->midi_substream_output, as this timer is used only for the output stream.

... and the revised patch is below.

...

@@ -230,9 +230,9 @@ static void snd_sb8dsp_midi_output_trigger(struct snd_rawmidi_substream *substre spin_lock_irqsave(&chip->open_lock, flags); if (up) { if (!(chip->open & SB_OPEN_MIDI_OUTPUT_TRIGGER)) {

• 	setup_timer(&chip->midi_timer,
  

• 		    snd_sb8dsp_midi_output_timer,
  

• 		    (unsigned long) substream);
  

• 	chip->timer_substream = substream;
  

• 	timer_setup(&chip->midi_timer,
  

• 		    snd_sb8dsp_midi_output_timer, 0);
  

I think it's OK to replace straightforwardly like this for this particular patch (so that the conversion becomes clearer), but ideally speaking, timer_setup() should go into either *_output_open() or snd_sb8dsp_midi() so that it's called only once per stream open or once at creation.

And, looking at the code closely now, it seems that del_timer_sync() is missing at the close side, too, but maybe it didn't matter much for such an old hardware :)

In the end, I kept timer_setup() call placed as is in v1 patch.

This call will be moved to the more appropriate place in another patch, as well as the additional call of missing del_timer_sync() at *_close().

thanks,

Takashi

-- 8< -- From: Kees Cook keescook@chromium.org Subject: [PATCH v2] ALSA: sb: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to all timer callbacks, switch to using the new timer_setup() and from_timer() to pass the timer pointer explicitly.

Signed-off-by: Kees Cook keescook@chromium.org Signed-off-by: Takashi Iwai tiwai@suse.de ---

v1->v2: Re-use the existing chip->midi_substream_output instead of assigning a new field to struct snd_sb

sound/isa/sb/emu8000_pcm.c | 6 +++--- sound/isa/sb/sb8_midi.c | 11 +++++------ 2 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/sound/isa/sb/emu8000_pcm.c b/sound/isa/sb/emu8000_pcm.c index 8f34551abd8d..bc5af71d3bdb 100644 --- a/sound/isa/sb/emu8000_pcm.c +++ b/sound/isa/sb/emu8000_pcm.c @@ -193,9 +193,9 @@ static inline int emu8k_get_curpos(struct snd_emu8k_pcm *rec, int ch) * timer interrupt handler * check the current position and update the period if necessary. */ -static void emu8k_pcm_timer_func(unsigned long data) +static void emu8k_pcm_timer_func(struct timer_list *t) { - struct snd_emu8k_pcm *rec = (struct snd_emu8k_pcm *)data; + struct snd_emu8k_pcm *rec = from_timer(rec, t, timer); int ptr, delta;

spin_lock(&rec->timer_lock); @@ -241,7 +241,7 @@ static int emu8k_pcm_open(struct snd_pcm_substream *subs) runtime->private_data = rec;

spin_lock_init(&rec->timer_lock); - setup_timer(&rec->timer, emu8k_pcm_timer_func, (unsigned long)rec); + timer_setup(&rec->timer, emu8k_pcm_timer_func, 0);

runtime->hw = emu8k_pcm_hw; runtime->hw.buffer_bytes_max = emu->mem_size - LOOP_BLANK_SIZE * 3; diff --git a/sound/isa/sb/sb8_midi.c b/sound/isa/sb/sb8_midi.c index bd672abb4854..05ba2c6b1a8c 100644 --- a/sound/isa/sb/sb8_midi.c +++ b/sound/isa/sb/sb8_midi.c @@ -209,10 +209,10 @@ static void snd_sb8dsp_midi_output_write(struct snd_rawmidi_substream *substream } }

-static void snd_sb8dsp_midi_output_timer(unsigned long data) +static void snd_sb8dsp_midi_output_timer(struct timer_list *t) { - struct snd_rawmidi_substream *substream = (struct snd_rawmidi_substream *) data; - struct snd_sb * chip = substream->rmidi->private_data; + struct snd_sb *chip = from_timer(chip, t, midi_timer); + struct snd_rawmidi_substream *substream = chip->midi_substream_output; unsigned long flags;

spin_lock_irqsave(&chip->open_lock, flags); @@ -230,9 +230,8 @@ static void snd_sb8dsp_midi_output_trigger(struct snd_rawmidi_substream *substre spin_lock_irqsave(&chip->open_lock, flags); if (up) { if (!(chip->open & SB_OPEN_MIDI_OUTPUT_TRIGGER)) { - setup_timer(&chip->midi_timer, - snd_sb8dsp_midi_output_timer, - (unsigned long) substream); + timer_setup(&chip->midi_timer, + snd_sb8dsp_midi_output_timer, 0); mod_timer(&chip->midi_timer, 1 + jiffies); chip->open |= SB_OPEN_MIDI_OUTPUT_TRIGGER; }