--- /dev/null
+/*
+ * ALSA sequencer Memory Manager
+ * Copyright (c) 1998 by Frank van de Pol <fvdpol@coil.demon.nl>
+ * Jaroslav Kysela <perex@perex.cz>
+ * 2000 by 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 <linux/vmalloc.h>
+#include <sound/core.h>
+
+#include <sound/seq_kernel.h>
+#include "seq_memory.h"
+#include "seq_queue.h"
+#include "seq_info.h"
+#include "seq_lock.h"
+
+static inline int snd_seq_pool_available(struct snd_seq_pool *pool)
+{
+ return pool->total_elements - atomic_read(&pool->counter);
+}
+
+static inline int snd_seq_output_ok(struct snd_seq_pool *pool)
+{
+ return snd_seq_pool_available(pool) >= pool->room;
+}
+
+/*
+ * Variable length event:
+ * The event like sysex uses variable length type.
+ * The external data may be stored in three different formats.
+ * 1) kernel space
+ * This is the normal case.
+ * ext.data.len = length
+ * ext.data.ptr = buffer pointer
+ * 2) user space
+ * When an event is generated via read(), the external data is
+ * kept in user space until expanded.
+ * ext.data.len = length | SNDRV_SEQ_EXT_USRPTR
+ * ext.data.ptr = userspace pointer
+ * 3) chained cells
+ * When the variable length event is enqueued (in prioq or fifo),
+ * the external data is decomposed to several cells.
+ * ext.data.len = length | SNDRV_SEQ_EXT_CHAINED
+ * ext.data.ptr = the additiona cell head
+ * -> cell.next -> cell.next -> ..
+ */
+
+/*
+ * exported:
+ * call dump function to expand external data.
+ */
+
+static int get_var_len(const struct snd_seq_event *event)
+{
+ if ((event->flags & SNDRV_SEQ_EVENT_LENGTH_MASK) != SNDRV_SEQ_EVENT_LENGTH_VARIABLE)
+ return -EINVAL;
+
+ return event->data.ext.len & ~SNDRV_SEQ_EXT_MASK;
+}
+
+int snd_seq_dump_var_event(const struct snd_seq_event *event,
+ snd_seq_dump_func_t func, void *private_data)
+{
+ int len, err;
+ struct snd_seq_event_cell *cell;
+
+ if ((len = get_var_len(event)) <= 0)
+ return len;
+
+ if (event->data.ext.len & SNDRV_SEQ_EXT_USRPTR) {
+ char buf[32];
+ char __user *curptr = (char __force __user *)event->data.ext.ptr;
+ while (len > 0) {
+ int size = sizeof(buf);
+ if (len < size)
+ size = len;
+ if (copy_from_user(buf, curptr, size))
+ return -EFAULT;
+ err = func(private_data, buf, size);
+ if (err < 0)
+ return err;
+ curptr += size;
+ len -= size;
+ }
+ return 0;
+ }
+ if (!(event->data.ext.len & SNDRV_SEQ_EXT_CHAINED))
+ return func(private_data, event->data.ext.ptr, len);
+
+ cell = (struct snd_seq_event_cell *)event->data.ext.ptr;
+ for (; len > 0 && cell; cell = cell->next) {
+ int size = sizeof(struct snd_seq_event);
+ if (len < size)
+ size = len;
+ err = func(private_data, &cell->event, size);
+ if (err < 0)
+ return err;
+ len -= size;
+ }
+ return 0;
+}
+
+EXPORT_SYMBOL(snd_seq_dump_var_event);
+
+
+/*
+ * exported:
+ * expand the variable length event to linear buffer space.
+ */
+
+static int seq_copy_in_kernel(char **bufptr, const void *src, int size)
+{
+ memcpy(*bufptr, src, size);
+ *bufptr += size;
+ return 0;
+}
+
+static int seq_copy_in_user(char __user **bufptr, const void *src, int size)
+{
+ if (copy_to_user(*bufptr, src, size))
+ return -EFAULT;
+ *bufptr += size;
+ return 0;
+}
+
+int snd_seq_expand_var_event(const struct snd_seq_event *event, int count, char *buf,
+ int in_kernel, int size_aligned)
+{
+ int len, newlen;
+ int err;
+
+ if ((len = get_var_len(event)) < 0)
+ return len;
+ newlen = len;
+ if (size_aligned > 0)
+ newlen = roundup(len, size_aligned);
+ if (count < newlen)
+ return -EAGAIN;
+
+ if (event->data.ext.len & SNDRV_SEQ_EXT_USRPTR) {
+ if (! in_kernel)
+ return -EINVAL;
+ if (copy_from_user(buf, (void __force __user *)event->data.ext.ptr, len))
+ return -EFAULT;
+ return newlen;
+ }
+ err = snd_seq_dump_var_event(event,
+ in_kernel ? (snd_seq_dump_func_t)seq_copy_in_kernel :
+ (snd_seq_dump_func_t)seq_copy_in_user,
+ &buf);
+ return err < 0 ? err : newlen;
+}
+
+EXPORT_SYMBOL(snd_seq_expand_var_event);
+
+/*
+ * release this cell, free extended data if available
+ */
+
+static inline void free_cell(struct snd_seq_pool *pool,
+ struct snd_seq_event_cell *cell)
+{
+ cell->next = pool->free;
+ pool->free = cell;
+ atomic_dec(&pool->counter);
+}
+
+void snd_seq_cell_free(struct snd_seq_event_cell * cell)
+{
+ unsigned long flags;
+ struct snd_seq_pool *pool;
+
+ if (snd_BUG_ON(!cell))
+ return;
+ pool = cell->pool;
+ if (snd_BUG_ON(!pool))
+ return;
+
+ spin_lock_irqsave(&pool->lock, flags);
+ free_cell(pool, cell);
+ if (snd_seq_ev_is_variable(&cell->event)) {
+ if (cell->event.data.ext.len & SNDRV_SEQ_EXT_CHAINED) {
+ struct snd_seq_event_cell *curp, *nextptr;
+ curp = cell->event.data.ext.ptr;
+ for (; curp; curp = nextptr) {
+ nextptr = curp->next;
+ curp->next = pool->free;
+ free_cell(pool, curp);
+ }
+ }
+ }
+ if (waitqueue_active(&pool->output_sleep)) {
+ /* has enough space now? */
+ if (snd_seq_output_ok(pool))
+ wake_up(&pool->output_sleep);
+ }
+ spin_unlock_irqrestore(&pool->lock, flags);
+}
+
+
+/*
+ * allocate an event cell.
+ */
+static int snd_seq_cell_alloc(struct snd_seq_pool *pool,
+ struct snd_seq_event_cell **cellp,
+ int nonblock, struct file *file)
+{
+ struct snd_seq_event_cell *cell;
+ unsigned long flags;
+ int err = -EAGAIN;
+ wait_queue_t wait;
+
+ if (pool == NULL)
+ return -EINVAL;
+
+ *cellp = NULL;
+
+ init_waitqueue_entry(&wait, current);
+ spin_lock_irqsave(&pool->lock, flags);
+ if (pool->ptr == NULL) { /* not initialized */
+ pr_debug("ALSA: seq: pool is not initialized\n");
+ err = -EINVAL;
+ goto __error;
+ }
+ while (pool->free == NULL && ! nonblock && ! pool->closing) {
+
+ set_current_state(TASK_INTERRUPTIBLE);
+ add_wait_queue(&pool->output_sleep, &wait);
+ spin_unlock_irq(&pool->lock);
+ schedule();
+ spin_lock_irq(&pool->lock);
+ remove_wait_queue(&pool->output_sleep, &wait);
+ /* interrupted? */
+ if (signal_pending(current)) {
+ err = -ERESTARTSYS;
+ goto __error;
+ }
+ }
+ if (pool->closing) { /* closing.. */
+ err = -ENOMEM;
+ goto __error;
+ }
+
+ cell = pool->free;
+ if (cell) {
+ int used;
+ pool->free = cell->next;
+ atomic_inc(&pool->counter);
+ used = atomic_read(&pool->counter);
+ if (pool->max_used < used)
+ pool->max_used = used;
+ pool->event_alloc_success++;
+ /* clear cell pointers */
+ cell->next = NULL;
+ err = 0;
+ } else
+ pool->event_alloc_failures++;
+ *cellp = cell;
+
+__error:
+ spin_unlock_irqrestore(&pool->lock, flags);
+ return err;
+}
+
+
+/*
+ * duplicate the event to a cell.
+ * if the event has external data, the data is decomposed to additional
+ * cells.
+ */
+int snd_seq_event_dup(struct snd_seq_pool *pool, struct snd_seq_event *event,
+ struct snd_seq_event_cell **cellp, int nonblock,
+ struct file *file)
+{
+ int ncells, err;
+ unsigned int extlen;
+ struct snd_seq_event_cell *cell;
+
+ *cellp = NULL;
+
+ ncells = 0;
+ extlen = 0;
+ if (snd_seq_ev_is_variable(event)) {
+ extlen = event->data.ext.len & ~SNDRV_SEQ_EXT_MASK;
+ ncells = (extlen + sizeof(struct snd_seq_event) - 1) / sizeof(struct snd_seq_event);
+ }
+ if (ncells >= pool->total_elements)
+ return -ENOMEM;
+
+ err = snd_seq_cell_alloc(pool, &cell, nonblock, file);
+ if (err < 0)
+ return err;
+
+ /* copy the event */
+ cell->event = *event;
+
+ /* decompose */
+ if (snd_seq_ev_is_variable(event)) {
+ int len = extlen;
+ int is_chained = event->data.ext.len & SNDRV_SEQ_EXT_CHAINED;
+ int is_usrptr = event->data.ext.len & SNDRV_SEQ_EXT_USRPTR;
+ struct snd_seq_event_cell *src, *tmp, *tail;
+ char *buf;
+
+ cell->event.data.ext.len = extlen | SNDRV_SEQ_EXT_CHAINED;
+ cell->event.data.ext.ptr = NULL;
+
+ src = (struct snd_seq_event_cell *)event->data.ext.ptr;
+ buf = (char *)event->data.ext.ptr;
+ tail = NULL;
+
+ while (ncells-- > 0) {
+ int size = sizeof(struct snd_seq_event);
+ if (len < size)
+ size = len;
+ err = snd_seq_cell_alloc(pool, &tmp, nonblock, file);
+ if (err < 0)
+ goto __error;
+ if (cell->event.data.ext.ptr == NULL)
+ cell->event.data.ext.ptr = tmp;
+ if (tail)
+ tail->next = tmp;
+ tail = tmp;
+ /* copy chunk */
+ if (is_chained && src) {
+ tmp->event = src->event;
+ src = src->next;
+ } else if (is_usrptr) {
+ if (copy_from_user(&tmp->event, (char __force __user *)buf, size)) {
+ err = -EFAULT;
+ goto __error;
+ }
+ } else {
+ memcpy(&tmp->event, buf, size);
+ }
+ buf += size;
+ len -= size;
+ }
+ }
+
+ *cellp = cell;
+ return 0;
+
+__error:
+ snd_seq_cell_free(cell);
+ return err;
+}
+
+
+/* poll wait */
+int snd_seq_pool_poll_wait(struct snd_seq_pool *pool, struct file *file,
+ poll_table *wait)
+{
+ poll_wait(file, &pool->output_sleep, wait);
+ return snd_seq_output_ok(pool);
+}
+
+
+/* allocate room specified number of events */
+int snd_seq_pool_init(struct snd_seq_pool *pool)
+{
+ int cell;
+ struct snd_seq_event_cell *cellptr;
+ unsigned long flags;
+
+ if (snd_BUG_ON(!pool))
+ return -EINVAL;
+ if (pool->ptr) /* should be atomic? */
+ return 0;
+
+ pool->ptr = vmalloc(sizeof(struct snd_seq_event_cell) * pool->size);
+ if (!pool->ptr)
+ return -ENOMEM;
+
+ /* add new cells to the free cell list */
+ spin_lock_irqsave(&pool->lock, flags);
+ pool->free = NULL;
+
+ for (cell = 0; cell < pool->size; cell++) {
+ cellptr = pool->ptr + cell;
+ cellptr->pool = pool;
+ cellptr->next = pool->free;
+ pool->free = cellptr;
+ }
+ pool->room = (pool->size + 1) / 2;
+
+ /* init statistics */
+ pool->max_used = 0;
+ pool->total_elements = pool->size;
+ spin_unlock_irqrestore(&pool->lock, flags);
+ return 0;
+}
+
+/* remove events */
+int snd_seq_pool_done(struct snd_seq_pool *pool)
+{
+ unsigned long flags;
+ struct snd_seq_event_cell *ptr;
+ int max_count = 5 * HZ;
+
+ if (snd_BUG_ON(!pool))
+ return -EINVAL;
+
+ /* wait for closing all threads */
+ spin_lock_irqsave(&pool->lock, flags);
+ pool->closing = 1;
+ spin_unlock_irqrestore(&pool->lock, flags);
+
+ if (waitqueue_active(&pool->output_sleep))
+ wake_up(&pool->output_sleep);
+
+ while (atomic_read(&pool->counter) > 0) {
+ if (max_count == 0) {
+ pr_warn("ALSA: snd_seq_pool_done timeout: %d cells remain\n", atomic_read(&pool->counter));
+ break;
+ }
+ schedule_timeout_uninterruptible(1);
+ max_count--;
+ }
+
+ /* release all resources */
+ spin_lock_irqsave(&pool->lock, flags);
+ ptr = pool->ptr;
+ pool->ptr = NULL;
+ pool->free = NULL;
+ pool->total_elements = 0;
+ spin_unlock_irqrestore(&pool->lock, flags);
+
+ vfree(ptr);
+
+ spin_lock_irqsave(&pool->lock, flags);
+ pool->closing = 0;
+ spin_unlock_irqrestore(&pool->lock, flags);
+
+ return 0;
+}
+
+
+/* init new memory pool */
+struct snd_seq_pool *snd_seq_pool_new(int poolsize)
+{
+ struct snd_seq_pool *pool;
+
+ /* create pool block */
+ pool = kzalloc(sizeof(*pool), GFP_KERNEL);
+ if (!pool)
+ return NULL;
+ spin_lock_init(&pool->lock);
+ pool->ptr = NULL;
+ pool->free = NULL;
+ pool->total_elements = 0;
+ atomic_set(&pool->counter, 0);
+ pool->closing = 0;
+ init_waitqueue_head(&pool->output_sleep);
+
+ pool->size = poolsize;
+
+ /* init statistics */
+ pool->max_used = 0;
+ return pool;
+}
+
+/* remove memory pool */
+int snd_seq_pool_delete(struct snd_seq_pool **ppool)
+{
+ struct snd_seq_pool *pool = *ppool;
+
+ *ppool = NULL;
+ if (pool == NULL)
+ return 0;
+ snd_seq_pool_done(pool);
+ kfree(pool);
+ return 0;
+}
+
+/* initialize sequencer memory */
+int __init snd_sequencer_memory_init(void)
+{
+ return 0;
+}
+
+/* release sequencer memory */
+void __exit snd_sequencer_memory_done(void)
+{
+}
+
+
+/* exported to seq_clientmgr.c */
+void snd_seq_info_pool(struct snd_info_buffer *buffer,
+ struct snd_seq_pool *pool, char *space)
+{
+ if (pool == NULL)
+ return;
+ snd_iprintf(buffer, "%sPool size : %d\n", space, pool->total_elements);
+ snd_iprintf(buffer, "%sCells in use : %d\n", space, atomic_read(&pool->counter));
+ snd_iprintf(buffer, "%sPeak cells in use : %d\n", space, pool->max_used);
+ snd_iprintf(buffer, "%sAlloc success : %d\n", space, pool->event_alloc_success);
+ snd_iprintf(buffer, "%sAlloc failures : %d\n", space, pool->event_alloc_failures);
+}
Code Review / kvmfornfv.git / blobdiff