[PATCH 3/8] staging: tidspbridge - change mmufault tasklet to a workqueue

[Fernando Guzman Lugo]

We don't need to manage the mmufault inside a tasklet
it is safer using a workqueue.

Signed-off-by: Fernando Guzman Lugo <x0095...@ti.com>
---
 drivers/staging/tidspbridge/core/dsp-mmu.c |   34 ++++++++++++++++++----------
 1 files changed, 22 insertions(+), 12 deletions(-)

diff --git a/drivers/staging/tidspbridge/core/dsp-mmu.c 
b/drivers/staging/tidspbridge/core/dsp-mmu.c
index 983c95a..6d7501a 100644
--- a/drivers/staging/tidspbridge/core/dsp-mmu.c
+++ b/drivers/staging/tidspbridge/core/dsp-mmu.c
@@ -28,7 +28,8 @@
 
 #define MMU_CNTL_TWL_EN                (1 << 2)
 
-static struct tasklet_struct mmu_tasklet;
+static struct workqueue_struct *mmu_wq;
+static struct work_struct fault_work;
 
 #ifdef CONFIG_TIDSPBRIDGE_BACKTRACE
 static void mmu_fault_print_stack(struct bridge_dev_context *dev_context)
@@ -37,7 +38,10 @@ static void mmu_fault_print_stack(struct bridge_dev_context 
*dev_context)
        u32 fa, tmp;
        struct iotlb_entry e;
        struct iommu *mmu = dev_context->dsp_mmu;
-       dummy_addr = (void *)__get_free_page(GFP_ATOMIC);
+
+       dummy_addr = (void *)__get_free_page(GFP_KERNEL);
+       if (!dummy_addr)
+               return;
 
        /*
         * Before acking the MMU fault, let's make sure MMU can only
@@ -76,19 +80,19 @@ static void mmu_fault_print_stack(struct bridge_dev_context 
*dev_context)
 #endif
 
 
-static void fault_tasklet(unsigned long data)
+static void mmu_fault_work(struct work_struct *work)
 {
-       struct iommu *mmu = (struct iommu *)data;
        struct bridge_dev_context *dev_ctx;
        struct deh_mgr *dm;
        u32 fa;
+
        dev_get_deh_mgr(dev_get_first(), &dm);
        dev_get_bridge_context(dev_get_first(), &dev_ctx);
 
        if (!dm || !dev_ctx)
                return;
 
-       fa = iommu_read_reg(mmu, MMU_FAULT_AD);
+       fa = iommu_read_reg(dev_ctx->dsp_mmu, MMU_FAULT_AD);
 
 #ifdef CONFIG_TIDSPBRIDGE_BACKTRACE
        print_dsp_trace_buffer(dev_ctx);
@@ -109,7 +113,8 @@ static int mmu_fault_callback(struct iommu *mmu)
                return -EPERM;
 
        iommu_write_reg(mmu, 0, MMU_IRQENABLE);
-       tasklet_schedule(&mmu_tasklet);
+       queue_work(mmu_wq, &fault_work);
+
        return 0;
 }
 
@@ -126,10 +131,16 @@ struct iommu *dsp_mmu_init()
 
        mmu = iommu_get("iva2");
 
-       if (!IS_ERR(mmu)) {
-               tasklet_init(&mmu_tasklet, fault_tasklet, (unsigned long)mmu);
-               mmu->isr = mmu_fault_callback;
+       if (IS_ERR(mmu))
+               return mmu;
+
+       mmu->isr = mmu_fault_callback;
+       mmu_wq = create_workqueue("dsp-mmu_wq");
+       if (!mmu_wq) {
+               iommu_put(mmu);
+               return ERR_PTR(-ENOMEM);
        }
+       INIT_WORK(&fault_work, mmu_fault_work);
 
        return mmu;
 }
@@ -143,9 +154,8 @@ struct iommu *dsp_mmu_init()
  */
 void dsp_mmu_exit(struct iommu *mmu)
 {
-       if (mmu)
-               iommu_put(mmu);
-       tasklet_kill(&mmu_tasklet);
+       iommu_put(mmu);
+       destroy_workqueue(mmu_wq);
 }
 
 /**
-- 
1.6.3.3

--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html