[PATCH v2 1/1] block: blk-merge: don't merge the pages with non-contiguous descriptors
From: Russell King - ARM Linux <hidden>
Date: 2013-01-16 23:14:27
Also in:
linux-arm-msm, linux-mmc, linux-scsi, lkml
On Wed, Jan 16, 2013 at 10:32:35AM +0000, James Bottomley wrote:
On Wed, 2013-01-16 at 12:07 +0530, Subhash Jadavani wrote:quoted
Now consider this call stack from MMC block driver (this is on the ARmv7 based board): [ 98.918174] [<c001b50c>] (v7_dma_inv_range+0x30/0x48) from [<c0017b8c>] (dma_cache_maint_page+0x1c4/0x24c) [ 98.927819] [<c0017b8c>] (dma_cache_maint_page+0x1c4/0x24c) from [<c0017c28>] (___dma_page_cpu_to_dev+0x14/0x1c) [ 98.937982] [<c0017c28>] (___dma_page_cpu_to_dev+0x14/0x1c) from [<c0017ff8>] (dma_map_sg+0x3c/0x114)OK, so this is showing that ARM itself is making the assumption that the pages are contiguous in the page offset map. Fix this by doing the increment via the pfn, which will do the right thing whatever the memory model. Signed-off-by: James Bottomley <redacted>
Ok. What would you like the patch summary line for this to be - the existing one seems to be a little wrong given the content of this patch...
quoted hunk ↗ jump to hunk
---diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 6b2fb87..ab88c5b 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c@@ -809,7 +809,7 @@ static void dma_cache_maint_page(struct page *page, unsigned long offset, op(vaddr, len, dir); } offset = 0; - page++; + page = pfn_to_page(page_to_pfn(page) + 1); left -= len; } while (left); }_______________________________________________ linux-arm-kernel mailing list linux-arm-kernel at lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel