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Diffstat (limited to 'cpukit/include/rtems/bdbuf.h')
-rw-r--r-- | cpukit/include/rtems/bdbuf.h | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/cpukit/include/rtems/bdbuf.h b/cpukit/include/rtems/bdbuf.h index fbb4fc05e9..4d11a47619 100644 --- a/cpukit/include/rtems/bdbuf.h +++ b/cpukit/include/rtems/bdbuf.h @@ -540,6 +540,29 @@ rtems_bdbuf_read ( ); /** + * @brief Give a hint which blocks should be cached next. + * + * Provide a hint to the read ahead mechanism which blocks should be cached + * next. This overwrites the default linear pattern. You should use it in (for + * example) a file system to tell bdbuf where the next part of a fragmented file + * is. If you know the length of the file, you can provide that too. + * + * Before you can use this function, the rtems_bdbuf_init() routine must be + * called at least once to initialize everything. Otherwise you might get + * unexpected results. + * + * @param dd [in] The disk device. + * @param block [in] Linear media block number. + * @param nr_blocks [in] Number of consecutive blocks that can be pre-fetched. + */ +void +rtems_bdbuf_peek ( + rtems_disk_device *dd, + rtems_blkdev_bnum block, + uint32_t nr_blocks +); + +/** * Release the buffer obtained by a read call back to the cache. If the buffer * was obtained by a get call and was not already in the cache the release * modified call should be used. A buffer released with this call obtained by a |