[5.14,419/432] drm/panfrost: Make sure MMU context lifetime is not bound to panfrost_priv

--- a/drivers/gpu/drm/panfrost/panfrost_device.h
+++ b/drivers/gpu/drm/panfrost/panfrost_device.h
@@ -121,8 +121,12 @@  struct panfrost_device {
 };
 
 struct panfrost_mmu {
+	struct panfrost_device *pfdev;
+	struct kref refcount;
 	struct io_pgtable_cfg pgtbl_cfg;
 	struct io_pgtable_ops *pgtbl_ops;
+	struct drm_mm mm;
+	spinlock_t mm_lock;
 	int as;
 	atomic_t as_count;
 	struct list_head list;
@@ -133,9 +137,7 @@  struct panfrost_file_priv {
 
 	struct drm_sched_entity sched_entity[NUM_JOB_SLOTS];
 
-	struct panfrost_mmu mmu;
-	struct drm_mm mm;
-	spinlock_t mm_lock;
+	struct panfrost_mmu *mmu;
 };
 
 static inline struct panfrost_device *to_panfrost_device(struct drm_device *ddev)
--- a/drivers/gpu/drm/panfrost/panfrost_drv.c
+++ b/drivers/gpu/drm/panfrost/panfrost_drv.c
@@ -417,7 +417,7 @@  static int panfrost_ioctl_madvise(struct
 		 * anyway, so let's not bother.
 		 */
 		if (!list_is_singular(&bo->mappings.list) ||
-		    WARN_ON_ONCE(first->mmu != &priv->mmu)) {
+		    WARN_ON_ONCE(first->mmu != priv->mmu)) {
 			ret = -EINVAL;
 			goto out_unlock_mappings;
 		}
@@ -449,32 +449,6 @@  int panfrost_unstable_ioctl_check(void)
 	return 0;
 }
 
-#define PFN_4G		(SZ_4G >> PAGE_SHIFT)
-#define PFN_4G_MASK	(PFN_4G - 1)
-#define PFN_16M		(SZ_16M >> PAGE_SHIFT)
-
-static void panfrost_drm_mm_color_adjust(const struct drm_mm_node *node,
-					 unsigned long color,
-					 u64 *start, u64 *end)
-{
-	/* Executable buffers can't start or end on a 4GB boundary */
-	if (!(color & PANFROST_BO_NOEXEC)) {
-		u64 next_seg;
-
-		if ((*start & PFN_4G_MASK) == 0)
-			(*start)++;
-
-		if ((*end & PFN_4G_MASK) == 0)
-			(*end)--;
-
-		next_seg = ALIGN(*start, PFN_4G);
-		if (next_seg - *start <= PFN_16M)
-			*start = next_seg + 1;
-
-		*end = min(*end, ALIGN(*start, PFN_4G) - 1);
-	}
-}
-
 static int
 panfrost_open(struct drm_device *dev, struct drm_file *file)
 {
@@ -489,15 +463,11 @@  panfrost_open(struct drm_device *dev, st
 	panfrost_priv->pfdev = pfdev;
 	file->driver_priv = panfrost_priv;
 
-	spin_lock_init(&panfrost_priv->mm_lock);
-
-	/* 4G enough for now. can be 48-bit */
-	drm_mm_init(&panfrost_priv->mm, SZ_32M >> PAGE_SHIFT, (SZ_4G - SZ_32M) >> PAGE_SHIFT);
-	panfrost_priv->mm.color_adjust = panfrost_drm_mm_color_adjust;
-
-	ret = panfrost_mmu_pgtable_alloc(panfrost_priv);
-	if (ret)
-		goto err_pgtable;
+	panfrost_priv->mmu = panfrost_mmu_ctx_create(pfdev);
+	if (IS_ERR(panfrost_priv->mmu)) {
+		ret = PTR_ERR(panfrost_priv->mmu);
+		goto err_free;
+	}
 
 	ret = panfrost_job_open(panfrost_priv);
 	if (ret)
@@ -506,9 +476,8 @@  panfrost_open(struct drm_device *dev, st
 	return 0;
 
 err_job:
-	panfrost_mmu_pgtable_free(panfrost_priv);
-err_pgtable:
-	drm_mm_takedown(&panfrost_priv->mm);
+	panfrost_mmu_ctx_put(panfrost_priv->mmu);
+err_free:
 	kfree(panfrost_priv);
 	return ret;
 }
@@ -521,8 +490,7 @@  panfrost_postclose(struct drm_device *de
 	panfrost_perfcnt_close(file);
 	panfrost_job_close(panfrost_priv);
 
-	panfrost_mmu_pgtable_free(panfrost_priv);
-	drm_mm_takedown(&panfrost_priv->mm);
+	panfrost_mmu_ctx_put(panfrost_priv->mmu);
 	kfree(panfrost_priv);
 }
 
--- a/drivers/gpu/drm/panfrost/panfrost_gem.c
+++ b/drivers/gpu/drm/panfrost/panfrost_gem.c
@@ -60,7 +60,7 @@  panfrost_gem_mapping_get(struct panfrost
 
 	mutex_lock(&bo->mappings.lock);
 	list_for_each_entry(iter, &bo->mappings.list, node) {
-		if (iter->mmu == &priv->mmu) {
+		if (iter->mmu == priv->mmu) {
 			kref_get(&iter->refcount);
 			mapping = iter;
 			break;
@@ -74,16 +74,13 @@  panfrost_gem_mapping_get(struct panfrost
 static void
 panfrost_gem_teardown_mapping(struct panfrost_gem_mapping *mapping)
 {
-	struct panfrost_file_priv *priv;
-
 	if (mapping->active)
 		panfrost_mmu_unmap(mapping);
 
-	priv = container_of(mapping->mmu, struct panfrost_file_priv, mmu);
-	spin_lock(&priv->mm_lock);
+	spin_lock(&mapping->mmu->mm_lock);
 	if (drm_mm_node_allocated(&mapping->mmnode))
 		drm_mm_remove_node(&mapping->mmnode);
-	spin_unlock(&priv->mm_lock);
+	spin_unlock(&mapping->mmu->mm_lock);
 }
 
 static void panfrost_gem_mapping_release(struct kref *kref)
@@ -94,6 +91,7 @@  static void panfrost_gem_mapping_release
 
 	panfrost_gem_teardown_mapping(mapping);
 	drm_gem_object_put(&mapping->obj->base.base);
+	panfrost_mmu_ctx_put(mapping->mmu);
 	kfree(mapping);
 }
 
@@ -143,11 +141,11 @@  int panfrost_gem_open(struct drm_gem_obj
 	else
 		align = size >= SZ_2M ? SZ_2M >> PAGE_SHIFT : 0;
 
-	mapping->mmu = &priv->mmu;
-	spin_lock(&priv->mm_lock);
-	ret = drm_mm_insert_node_generic(&priv->mm, &mapping->mmnode,
+	mapping->mmu = panfrost_mmu_ctx_get(priv->mmu);
+	spin_lock(&mapping->mmu->mm_lock);
+	ret = drm_mm_insert_node_generic(&mapping->mmu->mm, &mapping->mmnode,
 					 size >> PAGE_SHIFT, align, color, 0);
-	spin_unlock(&priv->mm_lock);
+	spin_unlock(&mapping->mmu->mm_lock);
 	if (ret)
 		goto err;
 
@@ -176,7 +174,7 @@  void panfrost_gem_close(struct drm_gem_o
 
 	mutex_lock(&bo->mappings.lock);
 	list_for_each_entry(iter, &bo->mappings.list, node) {
-		if (iter->mmu == &priv->mmu) {
+		if (iter->mmu == priv->mmu) {
 			mapping = iter;
 			list_del(&iter->node);
 			break;
--- a/drivers/gpu/drm/panfrost/panfrost_job.c
+++ b/drivers/gpu/drm/panfrost/panfrost_job.c
@@ -165,7 +165,7 @@  static void panfrost_job_hw_submit(struc
 		return;
 	}
 
-	cfg = panfrost_mmu_as_get(pfdev, &job->file_priv->mmu);
+	cfg = panfrost_mmu_as_get(pfdev, job->file_priv->mmu);
 
 	job_write(pfdev, JS_HEAD_NEXT_LO(js), jc_head & 0xFFFFFFFF);
 	job_write(pfdev, JS_HEAD_NEXT_HI(js), jc_head >> 32);
@@ -527,7 +527,7 @@  static irqreturn_t panfrost_job_irq_hand
 			if (job) {
 				pfdev->jobs[j] = NULL;
 
-				panfrost_mmu_as_put(pfdev, &job->file_priv->mmu);
+				panfrost_mmu_as_put(pfdev, job->file_priv->mmu);
 				panfrost_devfreq_record_idle(&pfdev->pfdevfreq);
 
 				dma_fence_signal_locked(job->done_fence);
--- a/drivers/gpu/drm/panfrost/panfrost_mmu.c
+++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c
@@ -1,5 +1,8 @@ 
 // SPDX-License-Identifier:	GPL-2.0
 /* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
+
+#include <drm/panfrost_drm.h>
+
 #include <linux/atomic.h>
 #include <linux/bitfield.h>
 #include <linux/delay.h>
@@ -337,7 +340,7 @@  static void mmu_tlb_inv_context_s1(void
 
 static void mmu_tlb_sync_context(void *cookie)
 {
-	//struct panfrost_device *pfdev = cookie;
+	//struct panfrost_mmu *mmu = cookie;
 	// TODO: Wait 1000 GPU cycles for HW_ISSUE_6367/T60X
 }
 
@@ -352,57 +355,10 @@  static const struct iommu_flush_ops mmu_
 	.tlb_flush_walk = mmu_tlb_flush_walk,
 };
 
-int panfrost_mmu_pgtable_alloc(struct panfrost_file_priv *priv)
-{
-	struct panfrost_mmu *mmu = &priv->mmu;
-	struct panfrost_device *pfdev = priv->pfdev;
-
-	INIT_LIST_HEAD(&mmu->list);
-	mmu->as = -1;
-
-	mmu->pgtbl_cfg = (struct io_pgtable_cfg) {
-		.pgsize_bitmap	= SZ_4K | SZ_2M,
-		.ias		= FIELD_GET(0xff, pfdev->features.mmu_features),
-		.oas		= FIELD_GET(0xff00, pfdev->features.mmu_features),
-		.coherent_walk	= pfdev->coherent,
-		.tlb		= &mmu_tlb_ops,
-		.iommu_dev	= pfdev->dev,
-	};
-
-	mmu->pgtbl_ops = alloc_io_pgtable_ops(ARM_MALI_LPAE, &mmu->pgtbl_cfg,
-					      priv);
-	if (!mmu->pgtbl_ops)
-		return -EINVAL;
-
-	return 0;
-}
-
-void panfrost_mmu_pgtable_free(struct panfrost_file_priv *priv)
-{
-	struct panfrost_device *pfdev = priv->pfdev;
-	struct panfrost_mmu *mmu = &priv->mmu;
-
-	spin_lock(&pfdev->as_lock);
-	if (mmu->as >= 0) {
-		pm_runtime_get_noresume(pfdev->dev);
-		if (pm_runtime_active(pfdev->dev))
-			panfrost_mmu_disable(pfdev, mmu->as);
-		pm_runtime_put_autosuspend(pfdev->dev);
-
-		clear_bit(mmu->as, &pfdev->as_alloc_mask);
-		clear_bit(mmu->as, &pfdev->as_in_use_mask);
-		list_del(&mmu->list);
-	}
-	spin_unlock(&pfdev->as_lock);
-
-	free_io_pgtable_ops(mmu->pgtbl_ops);
-}
-
 static struct panfrost_gem_mapping *
 addr_to_mapping(struct panfrost_device *pfdev, int as, u64 addr)
 {
 	struct panfrost_gem_mapping *mapping = NULL;
-	struct panfrost_file_priv *priv;
 	struct drm_mm_node *node;
 	u64 offset = addr >> PAGE_SHIFT;
 	struct panfrost_mmu *mmu;
@@ -415,11 +371,10 @@  addr_to_mapping(struct panfrost_device *
 	goto out;
 
 found_mmu:
-	priv = container_of(mmu, struct panfrost_file_priv, mmu);
 
-	spin_lock(&priv->mm_lock);
+	spin_lock(&mmu->mm_lock);
 
-	drm_mm_for_each_node(node, &priv->mm) {
+	drm_mm_for_each_node(node, &mmu->mm) {
 		if (offset >= node->start &&
 		    offset < (node->start + node->size)) {
 			mapping = drm_mm_node_to_panfrost_mapping(node);
@@ -429,7 +384,7 @@  found_mmu:
 		}
 	}
 
-	spin_unlock(&priv->mm_lock);
+	spin_unlock(&mmu->mm_lock);
 out:
 	spin_unlock(&pfdev->as_lock);
 	return mapping;
@@ -542,6 +497,107 @@  err_bo:
 	return ret;
 }
 
+static void panfrost_mmu_release_ctx(struct kref *kref)
+{
+	struct panfrost_mmu *mmu = container_of(kref, struct panfrost_mmu,
+						refcount);
+	struct panfrost_device *pfdev = mmu->pfdev;
+
+	spin_lock(&pfdev->as_lock);
+	if (mmu->as >= 0) {
+		pm_runtime_get_noresume(pfdev->dev);
+		if (pm_runtime_active(pfdev->dev))
+			panfrost_mmu_disable(pfdev, mmu->as);
+		pm_runtime_put_autosuspend(pfdev->dev);
+
+		clear_bit(mmu->as, &pfdev->as_alloc_mask);
+		clear_bit(mmu->as, &pfdev->as_in_use_mask);
+		list_del(&mmu->list);
+	}
+	spin_unlock(&pfdev->as_lock);
+
+	free_io_pgtable_ops(mmu->pgtbl_ops);
+	drm_mm_takedown(&mmu->mm);
+	kfree(mmu);
+}
+
+void panfrost_mmu_ctx_put(struct panfrost_mmu *mmu)
+{
+	kref_put(&mmu->refcount, panfrost_mmu_release_ctx);
+}
+
+struct panfrost_mmu *panfrost_mmu_ctx_get(struct panfrost_mmu *mmu)
+{
+	kref_get(&mmu->refcount);
+
+	return mmu;
+}
+
+#define PFN_4G		(SZ_4G >> PAGE_SHIFT)
+#define PFN_4G_MASK	(PFN_4G - 1)
+#define PFN_16M		(SZ_16M >> PAGE_SHIFT)
+
+static void panfrost_drm_mm_color_adjust(const struct drm_mm_node *node,
+					 unsigned long color,
+					 u64 *start, u64 *end)
+{
+	/* Executable buffers can't start or end on a 4GB boundary */
+	if (!(color & PANFROST_BO_NOEXEC)) {
+		u64 next_seg;
+
+		if ((*start & PFN_4G_MASK) == 0)
+			(*start)++;
+
+		if ((*end & PFN_4G_MASK) == 0)
+			(*end)--;
+
+		next_seg = ALIGN(*start, PFN_4G);
+		if (next_seg - *start <= PFN_16M)
+			*start = next_seg + 1;
+
+		*end = min(*end, ALIGN(*start, PFN_4G) - 1);
+	}
+}
+
+struct panfrost_mmu *panfrost_mmu_ctx_create(struct panfrost_device *pfdev)
+{
+	struct panfrost_mmu *mmu;
+
+	mmu = kzalloc(sizeof(*mmu), GFP_KERNEL);
+	if (!mmu)
+		return ERR_PTR(-ENOMEM);
+
+	mmu->pfdev = pfdev;
+	spin_lock_init(&mmu->mm_lock);
+
+	/* 4G enough for now. can be 48-bit */
+	drm_mm_init(&mmu->mm, SZ_32M >> PAGE_SHIFT, (SZ_4G - SZ_32M) >> PAGE_SHIFT);
+	mmu->mm.color_adjust = panfrost_drm_mm_color_adjust;
+
+	INIT_LIST_HEAD(&mmu->list);
+	mmu->as = -1;
+
+	mmu->pgtbl_cfg = (struct io_pgtable_cfg) {
+		.pgsize_bitmap	= SZ_4K | SZ_2M,
+		.ias		= FIELD_GET(0xff, pfdev->features.mmu_features),
+		.oas		= FIELD_GET(0xff00, pfdev->features.mmu_features),
+		.coherent_walk	= pfdev->coherent,
+		.tlb		= &mmu_tlb_ops,
+		.iommu_dev	= pfdev->dev,
+	};
+
+	mmu->pgtbl_ops = alloc_io_pgtable_ops(ARM_MALI_LPAE, &mmu->pgtbl_cfg,
+					      mmu);
+	if (!mmu->pgtbl_ops) {
+		kfree(mmu);
+		return ERR_PTR(-EINVAL);
+	}
+
+	kref_init(&mmu->refcount);
+
+	return mmu;
+}
+
 static const char *access_type_name(struct panfrost_device *pfdev,
 		u32 fault_status)
 {
--- a/drivers/gpu/drm/panfrost/panfrost_mmu.h
+++ b/drivers/gpu/drm/panfrost/panfrost_mmu.h
@@ -18,7 +18,8 @@  void panfrost_mmu_reset(struct panfrost_
 u32 panfrost_mmu_as_get(struct panfrost_device *pfdev, struct panfrost_mmu *mmu);
 void panfrost_mmu_as_put(struct panfrost_device *pfdev, struct panfrost_mmu *mmu);
 
-int panfrost_mmu_pgtable_alloc(struct panfrost_file_priv *priv);
-void panfrost_mmu_pgtable_free(struct panfrost_file_priv *priv);
+struct panfrost_mmu *panfrost_mmu_ctx_get(struct panfrost_mmu *mmu);
+void panfrost_mmu_ctx_put(struct panfrost_mmu *mmu);
+struct panfrost_mmu *panfrost_mmu_ctx_create(struct panfrost_device *pfdev);
 
 #endif