From efb012b361cf9319cd86ff169afa7550b7aa9336 Mon Sep 17 00:00:00 2001 From: Malahal Naineni Date: Fri, 1 Oct 2010 14:45:27 +0200 Subject: [PATCH] block: set the bounce_pfn to the actual DMA limit rather than to max memory The bounce_pfn of the request queue in 64 bit systems is set to the current max_low_pfn. Adding more memory later makes this incorrect. Memory allocated beyond this boot time max_low_pfn appear to require bounce buffers (bounce buffers are actually not allocated but used in calculating segments that may result in "over max segments limit" errors). Signed-off-by: Malahal Naineni Signed-off-by: Jens Axboe --- block/blk-settings.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/blk-settings.c b/block/blk-settings.c index f8f2ddf20613..a3600a7ab8bb 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -214,7 +214,7 @@ void blk_queue_bounce_limit(struct request_queue *q, u64 dma_mask) */ if (b_pfn < (min_t(u64, 0xffffffffUL, BLK_BOUNCE_HIGH) >> PAGE_SHIFT)) dma = 1; - q->limits.bounce_pfn = max_low_pfn; + q->limits.bounce_pfn = max(max_low_pfn, b_pfn); #else if (b_pfn < blk_max_low_pfn) dma = 1; -- 2.30.2