[PATCH 08/12] amd-iommu: enlarge the aperture dynamically

From: Joerg Roedel
Date: Fri May 22 2009 - 08:23:45 EST


[ impact: enable the new extended dma address allocator ]

Signed-off-by: Joerg Roedel <joerg.roedel@xxxxxxx>
---
arch/x86/kernel/amd_iommu.c | 20 ++++++++++++++++++--
1 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/amd_iommu.c b/arch/x86/kernel/amd_iommu.c
index 59ee1b9..d129d8f 100644
--- a/arch/x86/kernel/amd_iommu.c
+++ b/arch/x86/kernel/amd_iommu.c
@@ -1403,10 +1403,26 @@ static dma_addr_t __map_single(struct device *dev,
if (align)
align_mask = (1UL << get_order(size)) - 1;

+retry:
address = dma_ops_alloc_addresses(dev, dma_dom, pages, align_mask,
dma_mask);
- if (unlikely(address == bad_dma_address))
- goto out;
+ if (unlikely(address == bad_dma_address)) {
+ /*
+ * setting next_address here will let the address
+ * allocator only scan the new allocated range in the
+ * first run. This is a small optimization.
+ */
+ dma_dom->next_address = dma_dom->aperture_size;
+
+ if (alloc_new_range(iommu, dma_dom, false, GFP_ATOMIC))
+ goto out;
+
+ /*
+ * aperture was sucessfully enlarged by 128 MB, try
+ * allocation again
+ */
+ goto retry;
+ }

start = address;
for (i = 0; i < pages; ++i) {
--
1.6.3.1


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