[PATCH v2 5/8] dma-mapping: Support batch mode for dma_direct_sync_sg_for_*

[Barry Song <21cnbao@xxxxxxxxx>]

From: Barry Song <baohua@xxxxxxxxxx>

Instead of performing a flush per SG entry, issue all cache
operations first and then flush once. This ultimately benefits
__dma_sync_sg_for_cpu() and __dma_sync_sg_for_device().

Cc: Leon Romanovsky <leon@xxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
Cc: Robin Murphy <robin.murphy@xxxxxxx>
Cc: Ada Couprie Diaz <ada.coupriediaz@xxxxxxx>
Cc: Ard Biesheuvel <ardb@xxxxxxxxxx>
Cc: Marc Zyngier <maz@xxxxxxxxxx>
Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx>
Cc: Ryan Roberts <ryan.roberts@xxxxxxx>
Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx>
Cc: Tangquan Zheng <zhengtangquan@xxxxxxxx>
Signed-off-by: Barry Song <baohua@xxxxxxxxxx>
---
 kernel/dma/direct.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index a219911c7b90..98bacf562ca1 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -402,12 +402,12 @@ void dma_direct_sync_sg_for_device(struct device *dev,
 
                swiotlb_sync_single_for_device(dev, paddr, sg->length, dir);
 
-               if (!dev_is_dma_coherent(dev)) {
+               if (!dev_is_dma_coherent(dev))
                        arch_sync_dma_for_device(paddr, sg->length,
                                        dir);
-                       arch_sync_dma_flush();
-               }
        }
+       if (!dev_is_dma_coherent(dev))
+               arch_sync_dma_flush();
 }
 #endif
 
@@ -423,10 +423,8 @@ void dma_direct_sync_sg_for_cpu(struct device *dev,
        for_each_sg(sgl, sg, nents, i) {
                phys_addr_t paddr = dma_to_phys(dev, sg_dma_address(sg));
 
-               if (!dev_is_dma_coherent(dev)) {
+               if (!dev_is_dma_coherent(dev))
                        arch_sync_dma_for_cpu(paddr, sg->length, dir);
-                       arch_sync_dma_flush();
-               }
 
                swiotlb_sync_single_for_cpu(dev, paddr, sg->length, dir);
 
@@ -434,8 +432,10 @@ void dma_direct_sync_sg_for_cpu(struct device *dev,
                        arch_dma_mark_clean(paddr, sg->length);
        }
 
-       if (!dev_is_dma_coherent(dev))
+       if (!dev_is_dma_coherent(dev)) {
+               arch_sync_dma_flush();
                arch_sync_dma_for_cpu_all();
+       }
 }
 
 /*
-- 
2.43.0