| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * ALSA sequencer Memory Manager |
| 3 | * Copyright (c) 1998 by Frank van de Pol <fvdpol@coil.demon.nl> |
| 4 | * |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License as published by |
| 8 | * the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program; if not, write to the Free Software |
| 18 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 19 | * |
| 20 | */ |
| 21 | #ifndef __SND_SEQ_MEMORYMGR_H |
| 22 | #define __SND_SEQ_MEMORYMGR_H |
| 23 | |
| 24 | #include <sound/seq_kernel.h> |
| 25 | #include <linux/poll.h> |
| 26 | |
| 27 | typedef struct pool pool_t; |
| 28 | |
| 29 | /* container for sequencer event (internal use) */ |
| 30 | typedef struct snd_seq_event_cell_t { |
| 31 | snd_seq_event_t event; |
| 32 | pool_t *pool; /* used pool */ |
| 33 | struct snd_seq_event_cell_t *next; /* next cell */ |
| 34 | } snd_seq_event_cell_t; |
| 35 | |
| 36 | /* design note: the pool is a contigious block of memory, if we dynamicly |
| 37 | want to add additional cells to the pool be better store this in another |
| 38 | pool as we need to know the base address of the pool when releasing |
| 39 | memory. */ |
| 40 | |
| 41 | struct pool { |
| 42 | snd_seq_event_cell_t *ptr; /* pointer to first event chunk */ |
| 43 | snd_seq_event_cell_t *free; /* pointer to the head of the free list */ |
| 44 | |
| 45 | int total_elements; /* pool size actually allocated */ |
| 46 | atomic_t counter; /* cells free */ |
| 47 | |
| 48 | int size; /* pool size to be allocated */ |
| 49 | int room; /* watermark for sleep/wakeup */ |
| 50 | |
| 51 | int closing; |
| 52 | |
| 53 | /* statistics */ |
| 54 | int max_used; |
| 55 | int event_alloc_nopool; |
| 56 | int event_alloc_failures; |
| 57 | int event_alloc_success; |
| 58 | |
| 59 | /* Write locking */ |
| 60 | wait_queue_head_t output_sleep; |
| 61 | |
| 62 | /* Pool lock */ |
| 63 | spinlock_t lock; |
| 64 | }; |
| 65 | |
| 66 | extern void snd_seq_cell_free(snd_seq_event_cell_t* cell); |
| 67 | |
| 68 | int snd_seq_event_dup(pool_t *pool, snd_seq_event_t *event, snd_seq_event_cell_t **cellp, int nonblock, struct file *file); |
| 69 | |
| 70 | /* return number of unused (free) cells */ |
| 71 | static inline int snd_seq_unused_cells(pool_t *pool) |
| 72 | { |
| 73 | return pool ? pool->total_elements - atomic_read(&pool->counter) : 0; |
| 74 | } |
| 75 | |
| 76 | /* return total number of allocated cells */ |
| 77 | static inline int snd_seq_total_cells(pool_t *pool) |
| 78 | { |
| 79 | return pool ? pool->total_elements : 0; |
| 80 | } |
| 81 | |
| 82 | /* init pool - allocate events */ |
| 83 | int snd_seq_pool_init(pool_t *pool); |
| 84 | |
| 85 | /* done pool - free events */ |
| 86 | int snd_seq_pool_done(pool_t *pool); |
| 87 | |
| 88 | /* create pool */ |
| 89 | pool_t *snd_seq_pool_new(int poolsize); |
| 90 | |
| 91 | /* remove pool */ |
| 92 | int snd_seq_pool_delete(pool_t **pool); |
| 93 | |
| 94 | /* init memory */ |
| 95 | int snd_sequencer_memory_init(void); |
| 96 | |
| 97 | /* release event memory */ |
| 98 | void snd_sequencer_memory_done(void); |
| 99 | |
| 100 | /* polling */ |
| 101 | int snd_seq_pool_poll_wait(pool_t *pool, struct file *file, poll_table *wait); |
| 102 | |
| 103 | |
| 104 | #endif |