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seq_clientmgr.c
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seq_clientmgr.c
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/*
* ALSA sequencer Client Manager
* Copyright (c) 1998-2001 by Frank van de Pol <fvdpol@coil.demon.nl>
* Jaroslav Kysela <perex@perex.cz>
* Takashi Iwai <tiwai@suse.de>
*
*
* 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
*
*/
#include <linux/init.h>
#include <linux/export.h>
#include <linux/slab.h>
#include <sound/core.h>
#include <sound/minors.h>
#include <linux/kmod.h>
#include <sound/seq_kernel.h>
#include "seq_clientmgr.h"
#include "seq_memory.h"
#include "seq_queue.h"
#include "seq_timer.h"
#include "seq_info.h"
#include "seq_system.h"
#include <sound/seq_device.h>
#ifdef CONFIG_COMPAT
#include <linux/compat.h>
#endif
/* Client Manager
* this module handles the connections of userland and kernel clients
*
*/
/*
* There are four ranges of client numbers (last two shared):
* 0..15: global clients
* 16..127: statically allocated client numbers for cards 0..27
* 128..191: dynamically allocated client numbers for cards 28..31
* 128..191: dynamically allocated client numbers for applications
*/
/* number of kernel non-card clients */
#define SNDRV_SEQ_GLOBAL_CLIENTS 16
/* clients per cards, for static clients */
#define SNDRV_SEQ_CLIENTS_PER_CARD 4
/* dynamically allocated client numbers (both kernel drivers and user space) */
#define SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN 128
#define SNDRV_SEQ_LFLG_INPUT 0x0001
#define SNDRV_SEQ_LFLG_OUTPUT 0x0002
#define SNDRV_SEQ_LFLG_OPEN (SNDRV_SEQ_LFLG_INPUT|SNDRV_SEQ_LFLG_OUTPUT)
static DEFINE_SPINLOCK(clients_lock);
static DEFINE_MUTEX(register_mutex);
/*
* client table
*/
static char clienttablock[SNDRV_SEQ_MAX_CLIENTS];
static struct snd_seq_client *clienttab[SNDRV_SEQ_MAX_CLIENTS];
static struct snd_seq_usage client_usage;
/*
* prototypes
*/
static int bounce_error_event(struct snd_seq_client *client,
struct snd_seq_event *event,
int err, int atomic, int hop);
static int snd_seq_deliver_single_event(struct snd_seq_client *client,
struct snd_seq_event *event,
int filter, int atomic, int hop);
/*
*/
static inline unsigned short snd_seq_file_flags(struct file *file)
{
switch (file->f_mode & (FMODE_READ | FMODE_WRITE)) {
case FMODE_WRITE:
return SNDRV_SEQ_LFLG_OUTPUT;
case FMODE_READ:
return SNDRV_SEQ_LFLG_INPUT;
default:
return SNDRV_SEQ_LFLG_OPEN;
}
}
static inline int snd_seq_write_pool_allocated(struct snd_seq_client *client)
{
return snd_seq_total_cells(client->pool) > 0;
}
/* return pointer to client structure for specified id */
static struct snd_seq_client *clientptr(int clientid)
{
if (clientid < 0 || clientid >= SNDRV_SEQ_MAX_CLIENTS) {
pr_debug("ALSA: seq: oops. Trying to get pointer to client %d\n",
clientid);
return NULL;
}
return clienttab[clientid];
}
struct snd_seq_client *snd_seq_client_use_ptr(int clientid)
{
unsigned long flags;
struct snd_seq_client *client;
if (clientid < 0 || clientid >= SNDRV_SEQ_MAX_CLIENTS) {
pr_debug("ALSA: seq: oops. Trying to get pointer to client %d\n",
clientid);
return NULL;
}
spin_lock_irqsave(&clients_lock, flags);
client = clientptr(clientid);
if (client)
goto __lock;
if (clienttablock[clientid]) {
spin_unlock_irqrestore(&clients_lock, flags);
return NULL;
}
spin_unlock_irqrestore(&clients_lock, flags);
#ifdef CONFIG_MODULES
if (!in_interrupt()) {
static char client_requested[SNDRV_SEQ_GLOBAL_CLIENTS];
static char card_requested[SNDRV_CARDS];
if (clientid < SNDRV_SEQ_GLOBAL_CLIENTS) {
int idx;
if (!client_requested[clientid]) {
client_requested[clientid] = 1;
for (idx = 0; idx < 15; idx++) {
if (seq_client_load[idx] < 0)
break;
if (seq_client_load[idx] == clientid) {
request_module("snd-seq-client-%i",
clientid);
break;
}
}
}
} else if (clientid < SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN) {
int card = (clientid - SNDRV_SEQ_GLOBAL_CLIENTS) /
SNDRV_SEQ_CLIENTS_PER_CARD;
if (card < snd_ecards_limit) {
if (! card_requested[card]) {
card_requested[card] = 1;
snd_request_card(card);
}
snd_seq_device_load_drivers();
}
}
spin_lock_irqsave(&clients_lock, flags);
client = clientptr(clientid);
if (client)
goto __lock;
spin_unlock_irqrestore(&clients_lock, flags);
}
#endif
return NULL;
__lock:
snd_use_lock_use(&client->use_lock);
spin_unlock_irqrestore(&clients_lock, flags);
return client;
}
static void usage_alloc(struct snd_seq_usage *res, int num)
{
res->cur += num;
if (res->cur > res->peak)
res->peak = res->cur;
}
static void usage_free(struct snd_seq_usage *res, int num)
{
res->cur -= num;
}
/* initialise data structures */
int __init client_init_data(void)
{
/* zap out the client table */
memset(&clienttablock, 0, sizeof(clienttablock));
memset(&clienttab, 0, sizeof(clienttab));
return 0;
}
static struct snd_seq_client *seq_create_client1(int client_index, int poolsize)
{
unsigned long flags;
int c;
struct snd_seq_client *client;
/* init client data */
client = kzalloc(sizeof(*client), GFP_KERNEL);
if (client == NULL)
return NULL;
client->pool = snd_seq_pool_new(poolsize);
if (client->pool == NULL) {
kfree(client);
return NULL;
}
client->type = NO_CLIENT;
snd_use_lock_init(&client->use_lock);
rwlock_init(&client->ports_lock);
mutex_init(&client->ports_mutex);
INIT_LIST_HEAD(&client->ports_list_head);
mutex_init(&client->ioctl_mutex);
/* find free slot in the client table */
spin_lock_irqsave(&clients_lock, flags);
if (client_index < 0) {
for (c = SNDRV_SEQ_DYNAMIC_CLIENTS_BEGIN;
c < SNDRV_SEQ_MAX_CLIENTS;
c++) {
if (clienttab[c] || clienttablock[c])
continue;
clienttab[client->number = c] = client;
spin_unlock_irqrestore(&clients_lock, flags);
return client;
}
} else {
if (clienttab[client_index] == NULL && !clienttablock[client_index]) {
clienttab[client->number = client_index] = client;
spin_unlock_irqrestore(&clients_lock, flags);
return client;
}
}
spin_unlock_irqrestore(&clients_lock, flags);
snd_seq_pool_delete(&client->pool);
kfree(client);
return NULL; /* no free slot found or busy, return failure code */
}
static int seq_free_client1(struct snd_seq_client *client)
{
unsigned long flags;
if (!client)
return 0;
snd_seq_delete_all_ports(client);
snd_seq_queue_client_leave(client->number);
spin_lock_irqsave(&clients_lock, flags);
clienttablock[client->number] = 1;
clienttab[client->number] = NULL;
spin_unlock_irqrestore(&clients_lock, flags);
snd_use_lock_sync(&client->use_lock);
snd_seq_queue_client_termination(client->number);
if (client->pool)
snd_seq_pool_delete(&client->pool);
spin_lock_irqsave(&clients_lock, flags);
clienttablock[client->number] = 0;
spin_unlock_irqrestore(&clients_lock, flags);
return 0;
}
static void seq_free_client(struct snd_seq_client * client)
{
mutex_lock(®ister_mutex);
switch (client->type) {
case NO_CLIENT:
pr_warn("ALSA: seq: Trying to free unused client %d\n",
client->number);
break;
case USER_CLIENT:
case KERNEL_CLIENT:
seq_free_client1(client);
usage_free(&client_usage, 1);
break;
default:
pr_err("ALSA: seq: Trying to free client %d with undefined type = %d\n",
client->number, client->type);
}
mutex_unlock(®ister_mutex);
snd_seq_system_client_ev_client_exit(client->number);
}
/* -------------------------------------------------------- */
/* create a user client */
static int snd_seq_open(struct inode *inode, struct file *file)
{
int c, mode; /* client id */
struct snd_seq_client *client;
struct snd_seq_user_client *user;
int err;
err = nonseekable_open(inode, file);
if (err < 0)
return err;
if (mutex_lock_interruptible(®ister_mutex))
return -ERESTARTSYS;
client = seq_create_client1(-1, SNDRV_SEQ_DEFAULT_EVENTS);
if (client == NULL) {
mutex_unlock(®ister_mutex);
return -ENOMEM; /* failure code */
}
mode = snd_seq_file_flags(file);
if (mode & SNDRV_SEQ_LFLG_INPUT)
client->accept_input = 1;
if (mode & SNDRV_SEQ_LFLG_OUTPUT)
client->accept_output = 1;
user = &client->data.user;
user->fifo = NULL;
user->fifo_pool_size = 0;
if (mode & SNDRV_SEQ_LFLG_INPUT) {
user->fifo_pool_size = SNDRV_SEQ_DEFAULT_CLIENT_EVENTS;
user->fifo = snd_seq_fifo_new(user->fifo_pool_size);
if (user->fifo == NULL) {
seq_free_client1(client);
kfree(client);
mutex_unlock(®ister_mutex);
return -ENOMEM;
}
}
usage_alloc(&client_usage, 1);
client->type = USER_CLIENT;
mutex_unlock(®ister_mutex);
c = client->number;
file->private_data = client;
/* fill client data */
user->file = file;
sprintf(client->name, "Client-%d", c);
client->data.user.owner = get_pid(task_pid(current));
/* make others aware this new client */
snd_seq_system_client_ev_client_start(c);
return 0;
}
/* delete a user client */
static int snd_seq_release(struct inode *inode, struct file *file)
{
struct snd_seq_client *client = file->private_data;
if (client) {
seq_free_client(client);
if (client->data.user.fifo)
snd_seq_fifo_delete(&client->data.user.fifo);
put_pid(client->data.user.owner);
kfree(client);
}
return 0;
}
/* handle client read() */
/* possible error values:
* -ENXIO invalid client or file open mode
* -ENOSPC FIFO overflow (the flag is cleared after this error report)
* -EINVAL no enough user-space buffer to write the whole event
* -EFAULT seg. fault during copy to user space
*/
static ssize_t snd_seq_read(struct file *file, char __user *buf, size_t count,
loff_t *offset)
{
struct snd_seq_client *client = file->private_data;
struct snd_seq_fifo *fifo;
int err;
long result = 0;
struct snd_seq_event_cell *cell;
if (!(snd_seq_file_flags(file) & SNDRV_SEQ_LFLG_INPUT))
return -ENXIO;
if (!access_ok(VERIFY_WRITE, buf, count))
return -EFAULT;
/* check client structures are in place */
if (snd_BUG_ON(!client))
return -ENXIO;
if (!client->accept_input || (fifo = client->data.user.fifo) == NULL)
return -ENXIO;
if (atomic_read(&fifo->overflow) > 0) {
/* buffer overflow is detected */
snd_seq_fifo_clear(fifo);
/* return error code */
return -ENOSPC;
}
cell = NULL;
err = 0;
snd_seq_fifo_lock(fifo);
/* while data available in queue */
while (count >= sizeof(struct snd_seq_event)) {
int nonblock;
nonblock = (file->f_flags & O_NONBLOCK) || result > 0;
if ((err = snd_seq_fifo_cell_out(fifo, &cell, nonblock)) < 0) {
break;
}
if (snd_seq_ev_is_variable(&cell->event)) {
struct snd_seq_event tmpev;
tmpev = cell->event;
tmpev.data.ext.len &= ~SNDRV_SEQ_EXT_MASK;
if (copy_to_user(buf, &tmpev, sizeof(struct snd_seq_event))) {
err = -EFAULT;
break;
}
count -= sizeof(struct snd_seq_event);
buf += sizeof(struct snd_seq_event);
err = snd_seq_expand_var_event(&cell->event, count,
(char __force *)buf, 0,
sizeof(struct snd_seq_event));
if (err < 0)
break;
result += err;
count -= err;
buf += err;
} else {
if (copy_to_user(buf, &cell->event, sizeof(struct snd_seq_event))) {
err = -EFAULT;
break;
}
count -= sizeof(struct snd_seq_event);
buf += sizeof(struct snd_seq_event);
}
snd_seq_cell_free(cell);
cell = NULL; /* to be sure */
result += sizeof(struct snd_seq_event);
}
if (err < 0) {
if (cell)
snd_seq_fifo_cell_putback(fifo, cell);
if (err == -EAGAIN && result > 0)
err = 0;
}
snd_seq_fifo_unlock(fifo);
return (err < 0) ? err : result;
}
/*
* check access permission to the port
*/
static int check_port_perm(struct snd_seq_client_port *port, unsigned int flags)
{
if ((port->capability & flags) != flags)
return 0;
return flags;
}
/*
* check if the destination client is available, and return the pointer
* if filter is non-zero, client filter bitmap is tested.
*/
static struct snd_seq_client *get_event_dest_client(struct snd_seq_event *event,
int filter)
{
struct snd_seq_client *dest;
dest = snd_seq_client_use_ptr(event->dest.client);
if (dest == NULL)
return NULL;
if (! dest->accept_input)
goto __not_avail;
if ((dest->filter & SNDRV_SEQ_FILTER_USE_EVENT) &&
! test_bit(event->type, dest->event_filter))
goto __not_avail;
if (filter && !(dest->filter & filter))
goto __not_avail;
return dest; /* ok - accessible */
__not_avail:
snd_seq_client_unlock(dest);
return NULL;
}
/*
* Return the error event.
*
* If the receiver client is a user client, the original event is
* encapsulated in SNDRV_SEQ_EVENT_BOUNCE as variable length event. If
* the original event is also variable length, the external data is
* copied after the event record.
* If the receiver client is a kernel client, the original event is
* quoted in SNDRV_SEQ_EVENT_KERNEL_ERROR, since this requires no extra
* kmalloc.
*/
static int bounce_error_event(struct snd_seq_client *client,
struct snd_seq_event *event,
int err, int atomic, int hop)
{
struct snd_seq_event bounce_ev;
int result;
if (client == NULL ||
! (client->filter & SNDRV_SEQ_FILTER_BOUNCE) ||
! client->accept_input)
return 0; /* ignored */
/* set up quoted error */
memset(&bounce_ev, 0, sizeof(bounce_ev));
bounce_ev.type = SNDRV_SEQ_EVENT_KERNEL_ERROR;
bounce_ev.flags = SNDRV_SEQ_EVENT_LENGTH_FIXED;
bounce_ev.queue = SNDRV_SEQ_QUEUE_DIRECT;
bounce_ev.source.client = SNDRV_SEQ_CLIENT_SYSTEM;
bounce_ev.source.port = SNDRV_SEQ_PORT_SYSTEM_ANNOUNCE;
bounce_ev.dest.client = client->number;
bounce_ev.dest.port = event->source.port;
bounce_ev.data.quote.origin = event->dest;
bounce_ev.data.quote.event = event;
bounce_ev.data.quote.value = -err; /* use positive value */
result = snd_seq_deliver_single_event(NULL, &bounce_ev, 0, atomic, hop + 1);
if (result < 0) {
client->event_lost++;
return result;
}
return result;
}
/*
* rewrite the time-stamp of the event record with the curren time
* of the given queue.
* return non-zero if updated.
*/
static int update_timestamp_of_queue(struct snd_seq_event *event,
int queue, int real_time)
{
struct snd_seq_queue *q;
q = queueptr(queue);
if (! q)
return 0;
event->queue = queue;
event->flags &= ~SNDRV_SEQ_TIME_STAMP_MASK;
if (real_time) {
event->time.time = snd_seq_timer_get_cur_time(q->timer);
event->flags |= SNDRV_SEQ_TIME_STAMP_REAL;
} else {
event->time.tick = snd_seq_timer_get_cur_tick(q->timer);
event->flags |= SNDRV_SEQ_TIME_STAMP_TICK;
}
queuefree(q);
return 1;
}
/*
* deliver an event to the specified destination.
* if filter is non-zero, client filter bitmap is tested.
*
* RETURN VALUE: 0 : if succeeded
* <0 : error
*/
static int snd_seq_deliver_single_event(struct snd_seq_client *client,
struct snd_seq_event *event,
int filter, int atomic, int hop)
{
struct snd_seq_client *dest = NULL;
struct snd_seq_client_port *dest_port = NULL;
int result = -ENOENT;
int direct;
direct = snd_seq_ev_is_direct(event);
dest = get_event_dest_client(event, filter);
if (dest == NULL)
goto __skip;
dest_port = snd_seq_port_use_ptr(dest, event->dest.port);
if (dest_port == NULL)
goto __skip;
/* check permission */
if (! check_port_perm(dest_port, SNDRV_SEQ_PORT_CAP_WRITE)) {
result = -EPERM;
goto __skip;
}
if (dest_port->timestamping)
update_timestamp_of_queue(event, dest_port->time_queue,
dest_port->time_real);
switch (dest->type) {
case USER_CLIENT:
if (dest->data.user.fifo)
result = snd_seq_fifo_event_in(dest->data.user.fifo, event);
break;
case KERNEL_CLIENT:
if (dest_port->event_input == NULL)
break;
result = dest_port->event_input(event, direct,
dest_port->private_data,
atomic, hop);
break;
default:
break;
}
__skip:
if (dest_port)
snd_seq_port_unlock(dest_port);
if (dest)
snd_seq_client_unlock(dest);
if (result < 0 && !direct) {
result = bounce_error_event(client, event, result, atomic, hop);
}
return result;
}
/*
* send the event to all subscribers:
*/
static int deliver_to_subscribers(struct snd_seq_client *client,
struct snd_seq_event *event,
int atomic, int hop)
{
struct snd_seq_subscribers *subs;
int err, result = 0, num_ev = 0;
struct snd_seq_event event_saved;
struct snd_seq_client_port *src_port;
struct snd_seq_port_subs_info *grp;
src_port = snd_seq_port_use_ptr(client, event->source.port);
if (src_port == NULL)
return -EINVAL; /* invalid source port */
/* save original event record */
event_saved = *event;
grp = &src_port->c_src;
/* lock list */
if (atomic)
read_lock(&grp->list_lock);
else
down_read_nested(&grp->list_mutex, hop);
list_for_each_entry(subs, &grp->list_head, src_list) {
/* both ports ready? */
if (atomic_read(&subs->ref_count) != 2)
continue;
event->dest = subs->info.dest;
if (subs->info.flags & SNDRV_SEQ_PORT_SUBS_TIMESTAMP)
/* convert time according to flag with subscription */
update_timestamp_of_queue(event, subs->info.queue,
subs->info.flags & SNDRV_SEQ_PORT_SUBS_TIME_REAL);
err = snd_seq_deliver_single_event(client, event,
0, atomic, hop);
if (err < 0) {
/* save first error that occurs and continue */
if (!result)
result = err;
continue;
}
num_ev++;
/* restore original event record */
*event = event_saved;
}
if (atomic)
read_unlock(&grp->list_lock);
else
up_read(&grp->list_mutex);
*event = event_saved; /* restore */
snd_seq_port_unlock(src_port);
return (result < 0) ? result : num_ev;
}
#ifdef SUPPORT_BROADCAST
/*
* broadcast to all ports:
*/
static int port_broadcast_event(struct snd_seq_client *client,
struct snd_seq_event *event,
int atomic, int hop)
{
int num_ev = 0, err, result = 0;
struct snd_seq_client *dest_client;
struct snd_seq_client_port *port;
dest_client = get_event_dest_client(event, SNDRV_SEQ_FILTER_BROADCAST);
if (dest_client == NULL)
return 0; /* no matching destination */
read_lock(&dest_client->ports_lock);
list_for_each_entry(port, &dest_client->ports_list_head, list) {
event->dest.port = port->addr.port;
/* pass NULL as source client to avoid error bounce */
err = snd_seq_deliver_single_event(NULL, event,
SNDRV_SEQ_FILTER_BROADCAST,
atomic, hop);
if (err < 0) {
/* save first error that occurs and continue */
if (!result)
result = err;
continue;
}
num_ev++;
}
read_unlock(&dest_client->ports_lock);
snd_seq_client_unlock(dest_client);
event->dest.port = SNDRV_SEQ_ADDRESS_BROADCAST; /* restore */
return (result < 0) ? result : num_ev;
}
/*
* send the event to all clients:
* if destination port is also ADDRESS_BROADCAST, deliver to all ports.
*/
static int broadcast_event(struct snd_seq_client *client,
struct snd_seq_event *event, int atomic, int hop)
{
int err, result = 0, num_ev = 0;
int dest;
struct snd_seq_addr addr;
addr = event->dest; /* save */
for (dest = 0; dest < SNDRV_SEQ_MAX_CLIENTS; dest++) {
/* don't send to itself */
if (dest == client->number)
continue;
event->dest.client = dest;
event->dest.port = addr.port;
if (addr.port == SNDRV_SEQ_ADDRESS_BROADCAST)
err = port_broadcast_event(client, event, atomic, hop);
else
/* pass NULL as source client to avoid error bounce */
err = snd_seq_deliver_single_event(NULL, event,
SNDRV_SEQ_FILTER_BROADCAST,
atomic, hop);
if (err < 0) {
/* save first error that occurs and continue */
if (!result)
result = err;
continue;
}
num_ev += err;
}
event->dest = addr; /* restore */
return (result < 0) ? result : num_ev;
}
/* multicast - not supported yet */
static int multicast_event(struct snd_seq_client *client, struct snd_seq_event *event,
int atomic, int hop)
{
pr_debug("ALSA: seq: multicast not supported yet.\n");
return 0; /* ignored */
}
#endif /* SUPPORT_BROADCAST */
/* deliver an event to the destination port(s).
* if the event is to subscribers or broadcast, the event is dispatched
* to multiple targets.
*
* RETURN VALUE: n > 0 : the number of delivered events.
* n == 0 : the event was not passed to any client.
* n < 0 : error - event was not processed.
*/
static int snd_seq_deliver_event(struct snd_seq_client *client, struct snd_seq_event *event,
int atomic, int hop)
{
int result;
hop++;
if (hop >= SNDRV_SEQ_MAX_HOPS) {
pr_debug("ALSA: seq: too long delivery path (%d:%d->%d:%d)\n",
event->source.client, event->source.port,
event->dest.client, event->dest.port);
return -EMLINK;
}
if (snd_seq_ev_is_variable(event) &&
snd_BUG_ON(atomic && (event->data.ext.len & SNDRV_SEQ_EXT_USRPTR)))
return -EINVAL;
if (event->queue == SNDRV_SEQ_ADDRESS_SUBSCRIBERS ||
event->dest.client == SNDRV_SEQ_ADDRESS_SUBSCRIBERS)
result = deliver_to_subscribers(client, event, atomic, hop);
#ifdef SUPPORT_BROADCAST
else if (event->queue == SNDRV_SEQ_ADDRESS_BROADCAST ||
event->dest.client == SNDRV_SEQ_ADDRESS_BROADCAST)
result = broadcast_event(client, event, atomic, hop);
else if (event->dest.client >= SNDRV_SEQ_MAX_CLIENTS)
result = multicast_event(client, event, atomic, hop);
else if (event->dest.port == SNDRV_SEQ_ADDRESS_BROADCAST)
result = port_broadcast_event(client, event, atomic, hop);
#endif
else
result = snd_seq_deliver_single_event(client, event, 0, atomic, hop);
return result;
}
/*
* dispatch an event cell:
* This function is called only from queue check routines in timer
* interrupts or after enqueued.
* The event cell shall be released or re-queued in this function.
*
* RETURN VALUE: n > 0 : the number of delivered events.
* n == 0 : the event was not passed to any client.
* n < 0 : error - event was not processed.
*/
int snd_seq_dispatch_event(struct snd_seq_event_cell *cell, int atomic, int hop)
{
struct snd_seq_client *client;
int result;
if (snd_BUG_ON(!cell))
return -EINVAL;
client = snd_seq_client_use_ptr(cell->event.source.client);
if (client == NULL) {
snd_seq_cell_free(cell); /* release this cell */
return -EINVAL;
}
if (cell->event.type == SNDRV_SEQ_EVENT_NOTE) {
/* NOTE event:
* the event cell is re-used as a NOTE-OFF event and
* enqueued again.
*/
struct snd_seq_event tmpev, *ev;
/* reserve this event to enqueue note-off later */
tmpev = cell->event;
tmpev.type = SNDRV_SEQ_EVENT_NOTEON;
result = snd_seq_deliver_event(client, &tmpev, atomic, hop);
/*
* This was originally a note event. We now re-use the
* cell for the note-off event.
*/
ev = &cell->event;
ev->type = SNDRV_SEQ_EVENT_NOTEOFF;
ev->flags |= SNDRV_SEQ_PRIORITY_HIGH;
/* add the duration time */
switch (ev->flags & SNDRV_SEQ_TIME_STAMP_MASK) {
case SNDRV_SEQ_TIME_STAMP_TICK:
ev->time.tick += ev->data.note.duration;
break;
case SNDRV_SEQ_TIME_STAMP_REAL:
/* unit for duration is ms */
ev->time.time.tv_nsec += 1000000 * (ev->data.note.duration % 1000);
ev->time.time.tv_sec += ev->data.note.duration / 1000 +
ev->time.time.tv_nsec / 1000000000;
ev->time.time.tv_nsec %= 1000000000;
break;
}
ev->data.note.velocity = ev->data.note.off_velocity;
/* Now queue this cell as the note off event */
if (snd_seq_enqueue_event(cell, atomic, hop) < 0)
snd_seq_cell_free(cell); /* release this cell */
} else {
/* Normal events:
* event cell is freed after processing the event
*/
result = snd_seq_deliver_event(client, &cell->event, atomic, hop);
snd_seq_cell_free(cell);
}
snd_seq_client_unlock(client);
return result;
}
/* Allocate a cell from client pool and enqueue it to queue:
* if pool is empty and blocking is TRUE, sleep until a new cell is
* available.
*/
static int snd_seq_client_enqueue_event(struct snd_seq_client *client,
struct snd_seq_event *event,
struct file *file, int blocking,
int atomic, int hop)
{
struct snd_seq_event_cell *cell;
int err;
/* special queue values - force direct passing */
if (event->queue == SNDRV_SEQ_ADDRESS_SUBSCRIBERS) {
event->dest.client = SNDRV_SEQ_ADDRESS_SUBSCRIBERS;
event->queue = SNDRV_SEQ_QUEUE_DIRECT;
} else
#ifdef SUPPORT_BROADCAST
if (event->queue == SNDRV_SEQ_ADDRESS_BROADCAST) {
event->dest.client = SNDRV_SEQ_ADDRESS_BROADCAST;
event->queue = SNDRV_SEQ_QUEUE_DIRECT;
}
#endif
if (event->dest.client == SNDRV_SEQ_ADDRESS_SUBSCRIBERS) {
/* check presence of source port */
struct snd_seq_client_port *src_port = snd_seq_port_use_ptr(client, event->source.port);
if (src_port == NULL)
return -EINVAL;
snd_seq_port_unlock(src_port);
}
/* direct event processing without enqueued */
if (snd_seq_ev_is_direct(event)) {
if (event->type == SNDRV_SEQ_EVENT_NOTE)
return -EINVAL; /* this event must be enqueued! */
return snd_seq_deliver_event(client, event, atomic, hop);
}
/* Not direct, normal queuing */
if (snd_seq_queue_is_used(event->queue, client->number) <= 0)
return -EINVAL; /* invalid queue */
if (! snd_seq_write_pool_allocated(client))
return -ENXIO; /* queue is not allocated */
/* allocate an event cell */
err = snd_seq_event_dup(client->pool, event, &cell, !blocking || atomic, file);
if (err < 0)
return err;
/* we got a cell. enqueue it. */
if ((err = snd_seq_enqueue_event(cell, atomic, hop)) < 0) {
snd_seq_cell_free(cell);
return err;
}
return 0;
}
/*
* check validity of event type and data length.
* return non-zero if invalid.
*/
static int check_event_type_and_length(struct snd_seq_event *ev)
{
switch (snd_seq_ev_length_type(ev)) {
case SNDRV_SEQ_EVENT_LENGTH_FIXED:
if (snd_seq_ev_is_variable_type(ev))
return -EINVAL;
break;
case SNDRV_SEQ_EVENT_LENGTH_VARIABLE:
if (! snd_seq_ev_is_variable_type(ev) ||
(ev->data.ext.len & ~SNDRV_SEQ_EXT_MASK) >= SNDRV_SEQ_MAX_EVENT_LEN)
return -EINVAL;
break;
case SNDRV_SEQ_EVENT_LENGTH_VARUSR:
if (! snd_seq_ev_is_direct(ev))
return -EINVAL;
break;
}
return 0;
}
/* handle write() */
/* possible error values:
* -ENXIO invalid client or file open mode
* -ENOMEM malloc failed
* -EFAULT seg. fault during copy from user space
* -EINVAL invalid event
* -EAGAIN no space in output pool
* -EINTR interrupts while sleep
* -EMLINK too many hops
* others depends on return value from driver callback
*/