diff options
| -rw-r--r-- | arch/arm64/include/asm/barrier.h | 1 | ||||
| -rw-r--r-- | arch/arm64/include/asm/io.h | 1 | ||||
| -rw-r--r-- | drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 11 |
3 files changed, 11 insertions, 2 deletions
diff --git a/arch/arm64/include/asm/barrier.h b/arch/arm64/include/asm/barrier.h index fb4c27506ef4..c3009b0e5239 100644 --- a/arch/arm64/include/asm/barrier.h +++ b/arch/arm64/include/asm/barrier.h @@ -45,6 +45,7 @@ #define rmb() dsb(ld) #define wmb() dsb(st) +#define dma_mb() dmb(osh) #define dma_rmb() dmb(oshld) #define dma_wmb() dmb(oshst) diff --git a/arch/arm64/include/asm/io.h b/arch/arm64/include/asm/io.h index ff50dd731852..fd172c41df90 100644 --- a/arch/arm64/include/asm/io.h +++ b/arch/arm64/include/asm/io.h @@ -110,6 +110,7 @@ static inline u64 __raw_readq(const volatile void __iomem *addr) #define __io_par(v) __iormb(v) #define __iowmb() dma_wmb() +#define __iomb() dma_mb() /* * Relaxed I/O memory access primitives. These follow the Device memory diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c index 3063aeb38063..1ffec08d345a 100644 --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c @@ -810,7 +810,7 @@ static void queue_sync_cons_out(struct arm_smmu_queue *q) * Ensure that all CPU accesses (reads and writes) to the queue * are complete before we update the cons pointer. */ - mb(); + __iomb(); writel_relaxed(q->llq.cons, q->cons_reg); } @@ -822,8 +822,15 @@ static void queue_inc_cons(struct arm_smmu_ll_queue *q) static int queue_sync_prod_in(struct arm_smmu_queue *q) { + u32 prod; int ret = 0; - u32 prod = readl_relaxed(q->prod_reg); + + /* + * We can't use the _relaxed() variant here, as we must prevent + * speculative reads of the queue before we have determined that + * prod has indeed moved. + */ + prod = readl(q->prod_reg); if (Q_OVF(prod) != Q_OVF(q->llq.prod)) ret = -EOVERFLOW; |