From: Matthew Wilcox (Oracle) <willy@infradead.org>
Date: Wed, 15 May 2019 17:35:38 +0000 (-0400)
Subject: drm/i915: Convert vm_idr to XArray
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=9c8a6be4f84ec8931312359ddf57c500b35e621b;p=users%2Fwilly%2Fxarray.git

drm/i915: Convert vm_idr to XArray

Rename vm_idr to vms and remove the mutex protecting it.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index d93e319f88c0a..902bdb34c2bab 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -704,12 +704,6 @@ void i915_gem_contexts_fini(struct drm_i915_private *i915)
 	ida_destroy(&i915->contexts.hw_ida);
 }
 
-static int vm_idr_cleanup(int id, void *p, void *data)
-{
-	i915_vm_put(p);
-	return 0;
-}
-
 static int gem_context_register(struct i915_gem_context *ctx,
 				struct drm_i915_file_private *fpriv)
 {
@@ -745,10 +739,8 @@ int i915_gem_context_open(struct drm_i915_private *i915,
 	struct i915_gem_context *ctx;
 	int err;
 
-	mutex_init(&file_priv->vm_idr_lock);
-
 	xa_init_flags(&file_priv->contexts, XA_FLAGS_ALLOC);
-	idr_init_base(&file_priv->vm_idr, 1);
+	xa_init_flags(&file_priv->vms, XA_FLAGS_ALLOC1);
 
 	mutex_lock(&i915->drm.struct_mutex);
 	ctx = i915_gem_create_context(i915, 0);
@@ -770,9 +762,8 @@ int i915_gem_context_open(struct drm_i915_private *i915,
 err_ctx:
 	context_close(ctx);
 err:
-	idr_destroy(&file_priv->vm_idr);
+	xa_destroy(&file_priv->vms);
 	xa_destroy(&file_priv->contexts);
-	mutex_destroy(&file_priv->vm_idr_lock);
 	return err;
 }
 
@@ -780,15 +771,16 @@ void i915_gem_context_close(struct drm_file *file)
 {
 	struct drm_i915_file_private *file_priv = file->driver_priv;
 	struct i915_gem_context *ctx;
+	struct i915_address_space *vm;
 	unsigned long index;
 
 	xa_for_each(&file_priv->contexts, index, ctx)
 		context_close(ctx);
 	xa_destroy(&file_priv->contexts);
 
-	idr_for_each(&file_priv->vm_idr, vm_idr_cleanup, NULL);
-	idr_destroy(&file_priv->vm_idr);
-	mutex_destroy(&file_priv->vm_idr_lock);
+	xa_for_each(&file_priv->vms, index, vm)
+		i915_vm_put(vm);
+	xa_destroy(&file_priv->vms);
 }
 
 int i915_gem_vm_create_ioctl(struct drm_device *dev, void *data,
@@ -820,23 +812,15 @@ int i915_gem_vm_create_ioctl(struct drm_device *dev, void *data,
 			goto err_put;
 	}
 
-	err = mutex_lock_interruptible(&file_priv->vm_idr_lock);
-	if (err)
-		goto err_put;
-
-	err = idr_alloc(&file_priv->vm_idr, &ppgtt->vm, 0, 0, GFP_KERNEL);
+	err = xa_alloc(&file_priv->vms, &args->vm_id, &ppgtt->vm,
+			xa_limit_32b, GFP_KERNEL);
 	if (err < 0)
-		goto err_unlock;
-
-	GEM_BUG_ON(err == 0); /* reserved for invalid/unassigned ppgtt */
+		goto err_put;
 
-	mutex_unlock(&file_priv->vm_idr_lock);
+	GEM_BUG_ON(args->vm_id == 0); /* reserved for invalid/unassigned */
 
-	args->vm_id = err;
 	return 0;
 
-err_unlock:
-	mutex_unlock(&file_priv->vm_idr_lock);
 err_put:
 	i915_vm_put(&ppgtt->vm);
 	return err;
@@ -848,7 +832,6 @@ int i915_gem_vm_destroy_ioctl(struct drm_device *dev, void *data,
 	struct drm_i915_file_private *file_priv = file->driver_priv;
 	struct drm_i915_gem_vm_control *args = data;
 	struct i915_address_space *vm;
-	int err;
 	u32 id;
 
 	if (args->flags)
@@ -861,13 +844,7 @@ int i915_gem_vm_destroy_ioctl(struct drm_device *dev, void *data,
 	if (!id)
 		return -ENOENT;
 
-	err = mutex_lock_interruptible(&file_priv->vm_idr_lock);
-	if (err)
-		return err;
-
-	vm = idr_remove(&file_priv->vm_idr, id);
-
-	mutex_unlock(&file_priv->vm_idr_lock);
+	vm = xa_erase(&file_priv->vms, id);
 	if (!vm)
 		return -ENOENT;
 
@@ -963,6 +940,7 @@ static int get_ppgtt(struct drm_i915_file_private *file_priv,
 {
 	struct i915_address_space *vm;
 	int ret;
+	u32 id;
 
 	if (!ctx->vm)
 		return -ENODEV;
@@ -975,23 +953,15 @@ static int get_ppgtt(struct drm_i915_file_private *file_priv,
 	vm = i915_vm_get(ctx->vm);
 	mutex_unlock(&ctx->i915->drm.struct_mutex);
 
-	ret = mutex_lock_interruptible(&file_priv->vm_idr_lock);
-	if (ret)
-		goto err_put;
-
-	ret = idr_alloc(&file_priv->vm_idr, vm, 0, 0, GFP_KERNEL);
-	GEM_BUG_ON(!ret);
+	ret = xa_alloc(&file_priv->vms, &id, vm, xa_limit_32b, GFP_KERNEL);
 	if (ret < 0)
-		goto err_unlock;
-
-	i915_vm_get(vm);
+		goto err_put;
+	GEM_BUG_ON(!id);
 
 	args->size = 0;
-	args->value = ret;
+	args->value = id;
 
-	ret = 0;
-err_unlock:
-	mutex_unlock(&file_priv->vm_idr_lock);
+	return 0;
 err_put:
 	i915_vm_put(vm);
 	return ret;
@@ -1082,14 +1052,11 @@ static int set_ppgtt(struct drm_i915_file_private *file_priv,
 	if (upper_32_bits(args->value))
 		return -ENOENT;
 
-	err = mutex_lock_interruptible(&file_priv->vm_idr_lock);
-	if (err)
-		return err;
-
-	vm = idr_find(&file_priv->vm_idr, args->value);
+	xa_lock(&file_priv->vms);
+	vm = xa_load(&file_priv->vms, args->value);
 	if (vm)
 		i915_vm_get(vm);
-	mutex_unlock(&file_priv->vm_idr_lock);
+	xa_unlock(&file_priv->vms);
 	if (!vm)
 		return -ENOENT;
 
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index d84239cfd2bbf..41e37f72d67db 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -219,9 +219,7 @@ struct drm_i915_file_private {
 	} mm;
 
 	struct xarray contexts;
-
-	struct idr vm_idr;
-	struct mutex vm_idr_lock; /* guards vm_idr */
+	struct xarray vms;
 
 	unsigned int bsd_engine;