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       1                 :            : /* SPDX-License-Identifier: GPL-2.0-or-later */
       2                 :            : /*
       3                 :            :  *  ALSA sequencer Memory Manager
       4                 :            :  *  Copyright (c) 1998 by Frank van de Pol <fvdpol@coil.demon.nl>
       5                 :            :  */
       6                 :            : #ifndef __SND_SEQ_MEMORYMGR_H
       7                 :            : #define __SND_SEQ_MEMORYMGR_H
       8                 :            : 
       9                 :            : #include <sound/seq_kernel.h>
      10                 :            : #include <linux/poll.h>
      11                 :            : 
      12                 :            : struct snd_info_buffer;
      13                 :            : 
      14                 :            : /* container for sequencer event (internal use) */
      15                 :            : struct snd_seq_event_cell {
      16                 :            :         struct snd_seq_event event;
      17                 :            :         struct snd_seq_pool *pool;                              /* used pool */
      18                 :            :         struct snd_seq_event_cell *next;        /* next cell */
      19                 :            : };
      20                 :            : 
      21                 :            : /* design note: the pool is a contiguous block of memory, if we dynamicly
      22                 :            :    want to add additional cells to the pool be better store this in another
      23                 :            :    pool as we need to know the base address of the pool when releasing
      24                 :            :    memory. */
      25                 :            : 
      26                 :            : struct snd_seq_pool {
      27                 :            :         struct snd_seq_event_cell *ptr; /* pointer to first event chunk */
      28                 :            :         struct snd_seq_event_cell *free;        /* pointer to the head of the free list */
      29                 :            : 
      30                 :            :         int total_elements;     /* pool size actually allocated */
      31                 :            :         atomic_t counter;       /* cells free */
      32                 :            : 
      33                 :            :         int size;               /* pool size to be allocated */
      34                 :            :         int room;               /* watermark for sleep/wakeup */
      35                 :            : 
      36                 :            :         int closing;
      37                 :            : 
      38                 :            :         /* statistics */
      39                 :            :         int max_used;
      40                 :            :         int event_alloc_nopool;
      41                 :            :         int event_alloc_failures;
      42                 :            :         int event_alloc_success;
      43                 :            : 
      44                 :            :         /* Write locking */
      45                 :            :         wait_queue_head_t output_sleep;
      46                 :            : 
      47                 :            :         /* Pool lock */
      48                 :            :         spinlock_t lock;
      49                 :            : };
      50                 :            : 
      51                 :            : void snd_seq_cell_free(struct snd_seq_event_cell *cell);
      52                 :            : 
      53                 :            : int snd_seq_event_dup(struct snd_seq_pool *pool, struct snd_seq_event *event,
      54                 :            :                       struct snd_seq_event_cell **cellp, int nonblock,
      55                 :            :                       struct file *file, struct mutex *mutexp);
      56                 :            : 
      57                 :            : /* return number of unused (free) cells */
      58                 :          0 : static inline int snd_seq_unused_cells(struct snd_seq_pool *pool)
      59                 :            : {
      60         [ #  # ]:          0 :         return pool ? pool->total_elements - atomic_read(&pool->counter) : 0;
      61                 :            : }
      62                 :            : 
      63                 :            : /* return total number of allocated cells */
      64                 :          0 : static inline int snd_seq_total_cells(struct snd_seq_pool *pool)
      65                 :            : {
      66   [ #  #  #  #  :          0 :         return pool ? pool->total_elements : 0;
          #  #  #  #  #  
          #  #  #  #  #  
          #  #  #  #  #  
          #  #  #  #  #  
             #  #  #  # ]
      67                 :            : }
      68                 :            : 
      69                 :            : /* init pool - allocate events */
      70                 :            : int snd_seq_pool_init(struct snd_seq_pool *pool);
      71                 :            : 
      72                 :            : /* done pool - free events */
      73                 :            : void snd_seq_pool_mark_closing(struct snd_seq_pool *pool);
      74                 :            : int snd_seq_pool_done(struct snd_seq_pool *pool);
      75                 :            : 
      76                 :            : /* create pool */
      77                 :            : struct snd_seq_pool *snd_seq_pool_new(int poolsize);
      78                 :            : 
      79                 :            : /* remove pool */
      80                 :            : int snd_seq_pool_delete(struct snd_seq_pool **pool);
      81                 :            : 
      82                 :            : /* polling */
      83                 :            : int snd_seq_pool_poll_wait(struct snd_seq_pool *pool, struct file *file, poll_table *wait);
      84                 :            : 
      85                 :            : void snd_seq_info_pool(struct snd_info_buffer *buffer,
      86                 :            :                        struct snd_seq_pool *pool, char *space);
      87                 :            : 
      88                 :            : #endif