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 <joerg.roedel@amd.com>
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index a14f8dc..4565223 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -605,7 +605,9 @@
* 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 @@
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 @@
build_completion_wait(&cmd, (u64)&sem);
- ret = iommu_queue_command(iommu, &cmd);
+ ret = iommu_queue_command_sync(iommu, &cmd, false);
if (ret)
return ret;