diff options
Diffstat (limited to 'sound/core/seq/seq_midi.c')
| -rw-r--r-- | sound/core/seq/seq_midi.c | 55 |
1 files changed, 41 insertions, 14 deletions
diff --git a/sound/core/seq/seq_midi.c b/sound/core/seq/seq_midi.c index ca3f5fc30992..2eb12199c92f 100644 --- a/sound/core/seq/seq_midi.c +++ b/sound/core/seq/seq_midi.c @@ -24,6 +24,7 @@ Possible options for midisynth module: #include <sound/seq_device.h> #include <sound/seq_midi_event.h> #include <sound/initval.h> +#include "seq_lock.h" MODULE_AUTHOR("Frank van de Pol <fvdpol@coil.demon.nl>, Jaroslav Kysela <perex@perex.cz>"); MODULE_DESCRIPTION("Advanced Linux Sound Architecture sequencer MIDI synth."); @@ -42,6 +43,8 @@ struct seq_midisynth { int device; int subdevice; struct snd_rawmidi_file input_rfile; + spinlock_t output_lock; /* protects output_rfile publication */ + snd_use_lock_t output_use_lock; /* in-flight event_input users */ struct snd_rawmidi_file output_rfile; int seq_client; int seq_port; @@ -125,31 +128,42 @@ static int event_process_midi(struct snd_seq_event *ev, int direct, struct seq_midisynth *msynth = private_data; unsigned char msg[10]; /* buffer for constructing midi messages */ struct snd_rawmidi_substream *substream; + int err = 0; int len; if (snd_BUG_ON(!msynth)) return -EINVAL; - substream = msynth->output_rfile.output; - if (substream == NULL) - return -ENODEV; + + scoped_guard(spinlock_irqsave, &msynth->output_lock) { + substream = msynth->output_rfile.output; + if (!substream) + return -ENODEV; + snd_use_lock_use(&msynth->output_use_lock); + } + if (ev->type == SNDRV_SEQ_EVENT_SYSEX) { /* special case, to save space */ if ((ev->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE) { /* invalid event */ pr_debug("ALSA: seq_midi: invalid sysex event flags = 0x%x\n", ev->flags); - return 0; + goto out; } snd_seq_dump_var_event(ev, __dump_midi, substream); snd_midi_event_reset_decode(msynth->parser); } else { - if (msynth->parser == NULL) - return -EIO; + if (!msynth->parser) { + err = -EIO; + goto out; + } len = snd_midi_event_decode(msynth->parser, msg, sizeof(msg), ev); if (len < 0) - return 0; + goto out; if (dump_midi(substream, msg, len) < 0) snd_midi_event_reset_decode(msynth->parser); } - return 0; + +out: + snd_use_lock_free(&msynth->output_use_lock); + return err; } @@ -163,6 +177,8 @@ static int snd_seq_midisynth_new(struct seq_midisynth *msynth, msynth->card = card; msynth->device = device; msynth->subdevice = subdevice; + spin_lock_init(&msynth->output_lock); + snd_use_lock_init(&msynth->output_use_lock); return 0; } @@ -215,12 +231,13 @@ static int midisynth_use(void *private_data, struct snd_seq_port_subscribe *info { int err; struct seq_midisynth *msynth = private_data; + struct snd_rawmidi_file rfile = {}; struct snd_rawmidi_params params; /* open midi port */ err = snd_rawmidi_kernel_open(msynth->rmidi, msynth->subdevice, SNDRV_RAWMIDI_LFLG_OUTPUT, - &msynth->output_rfile); + &rfile); if (err < 0) { pr_debug("ALSA: seq_midi: midi output open failed!!!\n"); return err; @@ -229,12 +246,14 @@ static int midisynth_use(void *private_data, struct snd_seq_port_subscribe *info params.avail_min = 1; params.buffer_size = output_buffer_size; params.no_active_sensing = 1; - err = snd_rawmidi_output_params(msynth->output_rfile.output, ¶ms); + err = snd_rawmidi_output_params(rfile.output, ¶ms); if (err < 0) { - snd_rawmidi_kernel_release(&msynth->output_rfile); + snd_rawmidi_kernel_release(&rfile); return err; } snd_midi_event_reset_decode(msynth->parser); + scoped_guard(spinlock_irqsave, &msynth->output_lock) + msynth->output_rfile = rfile; return 0; } @@ -242,11 +261,19 @@ static int midisynth_use(void *private_data, struct snd_seq_port_subscribe *info static int midisynth_unuse(void *private_data, struct snd_seq_port_subscribe *info) { struct seq_midisynth *msynth = private_data; + struct snd_rawmidi_file rfile = {}; - if (snd_BUG_ON(!msynth->output_rfile.output)) + scoped_guard(spinlock_irqsave, &msynth->output_lock) { + rfile = msynth->output_rfile; + msynth->output_rfile = (struct snd_rawmidi_file){}; + } + + if (snd_BUG_ON(!rfile.output)) return -EINVAL; - snd_rawmidi_drain_output(msynth->output_rfile.output); - return snd_rawmidi_kernel_release(&msynth->output_rfile); + + snd_use_lock_sync(&msynth->output_use_lock); + snd_rawmidi_drain_output(rfile.output); + return snd_rawmidi_kernel_release(&rfile); } /* delete given midi synth port */ |