diff options
Diffstat (limited to 'drivers/md/dm-bufio.c')
| -rw-r--r-- | drivers/md/dm-bufio.c | 36 |
1 files changed, 34 insertions, 2 deletions
diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c index a1b58a65d8ed..66c5d130c8c2 100644 --- a/drivers/md/dm-bufio.c +++ b/drivers/md/dm-bufio.c @@ -104,6 +104,8 @@ struct dm_bufio_client { struct list_head reserved_buffers; unsigned need_reserved_buffers; + unsigned minimum_buffers; + struct hlist_head *cache_hash; wait_queue_head_t free_buffer_wait; @@ -861,8 +863,8 @@ static void __get_memory_limit(struct dm_bufio_client *c, buffers = dm_bufio_cache_size_per_client >> (c->sectors_per_block_bits + SECTOR_SHIFT); - if (buffers < DM_BUFIO_MIN_BUFFERS) - buffers = DM_BUFIO_MIN_BUFFERS; + if (buffers < c->minimum_buffers) + buffers = c->minimum_buffers; *limit_buffers = buffers; *threshold_buffers = buffers * DM_BUFIO_WRITEBACK_PERCENT / 100; @@ -1350,6 +1352,34 @@ retry: } EXPORT_SYMBOL_GPL(dm_bufio_release_move); +/* + * Free the given buffer. + * + * This is just a hint, if the buffer is in use or dirty, this function + * does nothing. + */ +void dm_bufio_forget(struct dm_bufio_client *c, sector_t block) +{ + struct dm_buffer *b; + + dm_bufio_lock(c); + + b = __find(c, block); + if (b && likely(!b->hold_count) && likely(!b->state)) { + __unlink_buffer(b); + __free_buffer_wake(b); + } + + dm_bufio_unlock(c); +} +EXPORT_SYMBOL(dm_bufio_forget); + +void dm_bufio_set_minimum_buffers(struct dm_bufio_client *c, unsigned n) +{ + c->minimum_buffers = n; +} +EXPORT_SYMBOL(dm_bufio_set_minimum_buffers); + unsigned dm_bufio_get_block_size(struct dm_bufio_client *c) { return c->block_size; @@ -1546,6 +1576,8 @@ struct dm_bufio_client *dm_bufio_client_create(struct block_device *bdev, unsign INIT_LIST_HEAD(&c->reserved_buffers); c->need_reserved_buffers = reserved_buffers; + c->minimum_buffers = DM_BUFIO_MIN_BUFFERS; + init_waitqueue_head(&c->free_buffer_wait); c->async_write_error = 0; |