diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/blk-settings.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/block/blk-settings.c b/block/blk-settings.c index 2c1831207a8f..c3632fc6d540 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -12,6 +12,7 @@ #include <linux/lcm.h> #include <linux/jiffies.h> #include <linux/gfp.h> +#include <linux/dma-mapping.h> #include "blk.h" #include "blk-wbt.h" @@ -832,6 +833,28 @@ void blk_queue_write_cache(struct request_queue *q, bool wc, bool fua) } EXPORT_SYMBOL_GPL(blk_queue_write_cache); +/** + * blk_queue_can_use_dma_map_merging - configure queue for merging segments. + * @q: the request queue for the device + * @dev: the device pointer for dma + * + * Tell the block layer about merging the segments by dma map of @q. + */ +bool blk_queue_can_use_dma_map_merging(struct request_queue *q, + struct device *dev) +{ + unsigned long boundary = dma_get_merge_boundary(dev); + + if (!boundary) + return false; + + /* No need to update max_segment_size. see blk_queue_virt_boundary() */ + blk_queue_virt_boundary(q, boundary); + + return true; +} +EXPORT_SYMBOL_GPL(blk_queue_can_use_dma_map_merging); + static int __init blk_settings_init(void) { blk_max_low_pfn = max_low_pfn - 1; |