From f1ca1512e765337a7c09eb875eedef8ea4e07654 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Fri, 2 Sep 2011 14:10:32 +0200 Subject: [PATCH] iommu/amd: Make sure iommu->need_sync contains correct value The value is only set to true but never set back to false, which causes to many completion-wait commands to be sent to hardware. Fix it with this patch. Cc: stable@kernel.org Signed-off-by: Joerg Roedel --- drivers/iommu/amd_iommu.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index a14f8dc23462..45652231dae8 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -605,7 +605,9 @@ static void build_inv_all(struct iommu_cmd *cmd) * Writes the command to the IOMMUs command buffer and informs the * hardware about the new command. */ -static int iommu_queue_command(struct amd_iommu *iommu, struct iommu_cmd *cmd) +static int iommu_queue_command_sync(struct amd_iommu *iommu, + struct iommu_cmd *cmd, + bool sync) { u32 left, tail, head, next_tail; unsigned long flags; @@ -639,13 +641,18 @@ again: copy_cmd_to_buffer(iommu, cmd, tail); /* We need to sync now to make sure all commands are processed */ - iommu->need_sync = true; + iommu->need_sync = sync; spin_unlock_irqrestore(&iommu->lock, flags); return 0; } +static int iommu_queue_command(struct amd_iommu *iommu, struct iommu_cmd *cmd) +{ + return iommu_queue_command_sync(iommu, cmd, true); +} + /* * This function queues a completion wait command into the command * buffer of an IOMMU @@ -661,7 +668,7 @@ static int iommu_completion_wait(struct amd_iommu *iommu) build_completion_wait(&cmd, (u64)&sem); - ret = iommu_queue_command(iommu, &cmd); + ret = iommu_queue_command_sync(iommu, &cmd, false); if (ret) return ret; -- 2.11.0