drivers/misc/habanalabs/common/context.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0

 /*
  * Copyright 2016-2019 HabanaLabs, Ltd.
  * All Rights Reserved.
  */

 #include "habanalabs.h"

 #include <linux/slab.h>

 static void hl_ctx_fini(struct hl_ctx *ctx)
 {
 	struct hl_device *hdev = ctx->hdev;
 	u64 idle_mask[HL_BUSY_ENGINES_MASK_EXT_SIZE] = {0};
 	int i;

 	/* Release all allocated pending cb's, those cb's were never
 	 * scheduled so it is safe to release them here
 	 */
 	hl_pending_cb_list_flush(ctx);

 	/*
 	 * If we arrived here, there are no jobs waiting for this context
 	 * on its queues so we can safely remove it.
 	 * This is because for each CS, we increment the ref count and for
 	 * every CS that was finished we decrement it and we won't arrive
 	 * to this function unless the ref count is 0
 	 */

 	for (i = 0 ; i < hdev->asic_prop.max_pending_cs ; i++)
 		hl_fence_put(ctx->cs_pending[i]);

 	kfree(ctx->cs_pending);

 	if (ctx->asid != HL_KERNEL_ASID_ID) {
 		dev_dbg(hdev->dev, "closing user context %d\n", ctx->asid);

 		/* The engines are stopped as there is no executing CS, but the
 		 * Coresight might be still working by accessing addresses
 		 * related to the stopped engines. Hence stop it explicitly.
 		 * Stop only if this is the compute context, as there can be
 		 * only one compute context
 		 */
 		if ((hdev->in_debug) && (hdev->compute_ctx == ctx))
 			hl_device_set_debug_mode(hdev, false);

 		hdev->asic_funcs->ctx_fini(ctx);
 		hl_cb_va_pool_fini(ctx);
 		hl_vm_ctx_fini(ctx);
 		hl_asid_free(hdev, ctx->asid);

 		/* Scrub both SRAM and DRAM */
 		hdev->asic_funcs->scrub_device_mem(hdev, 0, 0);

 		if ((!hdev->pldm) && (hdev->pdev) &&
 				(!hdev->asic_funcs->is_device_idle(hdev,
 					idle_mask,
 					HL_BUSY_ENGINES_MASK_EXT_SIZE, NULL)))
 			dev_notice(hdev->dev,
 					"device not idle after user context is closed (0x%llx, 0x%llx)\n",
 						idle_mask[0], idle_mask[1]);
 	} else {
 		dev_dbg(hdev->dev, "closing kernel context\n");
 		hdev->asic_funcs->ctx_fini(ctx);
 		hl_vm_ctx_fini(ctx);
 		hl_mmu_ctx_fini(ctx);
 	}
 }

 void hl_ctx_do_release(struct kref *ref)
 {
 	struct hl_ctx *ctx;

 	ctx = container_of(ref, struct hl_ctx, refcount);

 	hl_ctx_fini(ctx);

 	if (ctx->hpriv)
 		hl_hpriv_put(ctx->hpriv);

 	kfree(ctx);
 }

 int hl_ctx_create(struct hl_device *hdev, struct hl_fpriv *hpriv)
 {
 	struct hl_ctx_mgr *mgr = &hpriv->ctx_mgr;
 	struct hl_ctx *ctx;
 	int rc;

 	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
 	if (!ctx) {
 		rc = -ENOMEM;
 		goto out_err;
 	}

 	mutex_lock(&mgr->ctx_lock);
 	rc = idr_alloc(&mgr->ctx_handles, ctx, 1, 0, GFP_KERNEL);
 	mutex_unlock(&mgr->ctx_lock);

 	if (rc < 0) {
 		dev_err(hdev->dev, "Failed to allocate IDR for a new CTX\n");
 		goto free_ctx;
 	}

 	ctx->handle = rc;

 	rc = hl_ctx_init(hdev, ctx, false);
 	if (rc)
 		goto remove_from_idr;

 	hl_hpriv_get(hpriv);
 	ctx->hpriv = hpriv;

 	/* TODO: remove for multiple contexts per process */
 	hpriv->ctx = ctx;

 	/* TODO: remove the following line for multiple process support */
 	hdev->compute_ctx = ctx;

 	return 0;

 remove_from_idr:
 	mutex_lock(&mgr->ctx_lock);
 	idr_remove(&mgr->ctx_handles, ctx->handle);
 	mutex_unlock(&mgr->ctx_lock);
 free_ctx:
 	kfree(ctx);
 out_err:
 	return rc;
 }

 void hl_ctx_free(struct hl_device *hdev, struct hl_ctx *ctx)
 {
 	if (kref_put(&ctx->refcount, hl_ctx_do_release) == 1)
 		return;

 	dev_warn(hdev->dev,
 		"user process released device but its command submissions are still executing\n");
 }

 int hl_ctx_init(struct hl_device *hdev, struct hl_ctx *ctx, bool is_kernel_ctx)
 {
 	int rc = 0;

 	ctx->hdev = hdev;

 	kref_init(&ctx->refcount);

 	ctx->cs_sequence = 1;
 	INIT_LIST_HEAD(&ctx->pending_cb_list);
 	spin_lock_init(&ctx->pending_cb_lock);
 	spin_lock_init(&ctx->cs_lock);
 	atomic_set(&ctx->thread_ctx_switch_token, 1);
 	atomic_set(&ctx->thread_pending_cb_token, 1);
 	ctx->thread_ctx_switch_wait_token = 0;
 	ctx->cs_pending = kcalloc(hdev->asic_prop.max_pending_cs,
 				sizeof(struct hl_fence *),
 				GFP_KERNEL);
 	if (!ctx->cs_pending)
 		return -ENOMEM;

 	if (is_kernel_ctx) {
 		ctx->asid = HL_KERNEL_ASID_ID; /* Kernel driver gets ASID 0 */
 		rc = hl_vm_ctx_init(ctx);
 		if (rc) {
 			dev_err(hdev->dev, "Failed to init mem ctx module\n");
 			rc = -ENOMEM;
 			goto err_free_cs_pending;
 		}

 		rc = hdev->asic_funcs->ctx_init(ctx);
 		if (rc) {
 			dev_err(hdev->dev, "ctx_init failed\n");
 			goto err_vm_ctx_fini;
 		}
 	} else {
 		ctx->asid = hl_asid_alloc(hdev);
 		if (!ctx->asid) {
 			dev_err(hdev->dev, "No free ASID, failed to create context\n");
 			rc = -ENOMEM;
 			goto err_free_cs_pending;
 		}

 		rc = hl_vm_ctx_init(ctx);
 		if (rc) {
 			dev_err(hdev->dev, "Failed to init mem ctx module\n");
 			rc = -ENOMEM;
 			goto err_asid_free;
 		}

 		rc = hl_cb_va_pool_init(ctx);
 		if (rc) {
 			dev_err(hdev->dev,
 				"Failed to init VA pool for mapped CB\n");
 			goto err_vm_ctx_fini;
 		}

 		rc = hdev->asic_funcs->ctx_init(ctx);
 		if (rc) {
 			dev_err(hdev->dev, "ctx_init failed\n");
 			goto err_cb_va_pool_fini;
 		}

 		dev_dbg(hdev->dev, "create user context %d\n", ctx->asid);
 	}

 	return 0;

 err_cb_va_pool_fini:
 	hl_cb_va_pool_fini(ctx);
 err_vm_ctx_fini:
 	hl_vm_ctx_fini(ctx);
 err_asid_free:
 	if (ctx->asid != HL_KERNEL_ASID_ID)
 		hl_asid_free(hdev, ctx->asid);
 err_free_cs_pending:
 	kfree(ctx->cs_pending);

 	return rc;
 }

 void hl_ctx_get(struct hl_device *hdev, struct hl_ctx *ctx)
 {
 	kref_get(&ctx->refcount);
 }

 int hl_ctx_put(struct hl_ctx *ctx)
 {
 	return kref_put(&ctx->refcount, hl_ctx_do_release);
 }

 struct hl_fence *hl_ctx_get_fence(struct hl_ctx *ctx, u64 seq)
 {
 	struct asic_fixed_properties *asic_prop = &ctx->hdev->asic_prop;
 	struct hl_fence *fence;

 	spin_lock(&ctx->cs_lock);

 	if (seq >= ctx->cs_sequence) {
 		spin_unlock(&ctx->cs_lock);
 		return ERR_PTR(-EINVAL);
 	}

 	if (seq + asic_prop->max_pending_cs < ctx->cs_sequence) {
 		spin_unlock(&ctx->cs_lock);
 		return NULL;
 	}

 	fence = ctx->cs_pending[seq & (asic_prop->max_pending_cs - 1)];
 	hl_fence_get(fence);

 	spin_unlock(&ctx->cs_lock);

 	return fence;
 }

 /*
  * hl_ctx_mgr_init - initialize the context manager
  *
  * @mgr: pointer to context manager structure
  *
  * This manager is an object inside the hpriv object of the user process.
  * The function is called when a user process opens the FD.
  */
 void hl_ctx_mgr_init(struct hl_ctx_mgr *mgr)
 {
 	mutex_init(&mgr->ctx_lock);
 	idr_init(&mgr->ctx_handles);
 }

 /*
  * hl_ctx_mgr_fini - finalize the context manager
  *
  * @hdev: pointer to device structure
  * @mgr: pointer to context manager structure
  *
  * This function goes over all the contexts in the manager and frees them.
  * It is called when a process closes the FD.
  */
 void hl_ctx_mgr_fini(struct hl_device *hdev, struct hl_ctx_mgr *mgr)
 {
 	struct hl_ctx *ctx;
 	struct idr *idp;
 	u32 id;

 	idp = &mgr->ctx_handles;

 	idr_for_each_entry(idp, ctx, id)
 		hl_ctx_free(hdev, ctx);

 	idr_destroy(&mgr->ctx_handles);
 	mutex_destroy(&mgr->ctx_lock);
 }
	// SPDX-License-Identifier: GPL-2.0

	/*
	* Copyright 2016-2019 HabanaLabs, Ltd.
	* All Rights Reserved.
	*/

	#include "habanalabs.h"

	#include <linux/slab.h>

	static void hl_ctx_fini(struct hl_ctx *ctx)
	{
	struct hl_device *hdev = ctx->hdev;
	u64 idle_mask[HL_BUSY_ENGINES_MASK_EXT_SIZE] = {0};
	int i;

	/* Release all allocated pending cb's, those cb's were never
	* scheduled so it is safe to release them here
	*/
	hl_pending_cb_list_flush(ctx);

	/*
	* If we arrived here, there are no jobs waiting for this context
	* on its queues so we can safely remove it.
	* This is because for each CS, we increment the ref count and for
	* every CS that was finished we decrement it and we won't arrive
	* to this function unless the ref count is 0
	*/

	for (i = 0 ; i < hdev->asic_prop.max_pending_cs ; i++)
	hl_fence_put(ctx->cs_pending[i]);

	kfree(ctx->cs_pending);

	if (ctx->asid != HL_KERNEL_ASID_ID) {
	dev_dbg(hdev->dev, "closing user context %d\n", ctx->asid);

	/* The engines are stopped as there is no executing CS, but the
	* Coresight might be still working by accessing addresses
	* related to the stopped engines. Hence stop it explicitly.
	* Stop only if this is the compute context, as there can be
	* only one compute context
	*/
	if ((hdev->in_debug) && (hdev->compute_ctx == ctx))
	hl_device_set_debug_mode(hdev, false);

	hdev->asic_funcs->ctx_fini(ctx);
	hl_cb_va_pool_fini(ctx);
	hl_vm_ctx_fini(ctx);
	hl_asid_free(hdev, ctx->asid);

	/* Scrub both SRAM and DRAM */
	hdev->asic_funcs->scrub_device_mem(hdev, 0, 0);

	if ((!hdev->pldm) && (hdev->pdev) &&
	(!hdev->asic_funcs->is_device_idle(hdev,
	idle_mask,
	HL_BUSY_ENGINES_MASK_EXT_SIZE, NULL)))
	dev_notice(hdev->dev,
	"device not idle after user context is closed (0x%llx, 0x%llx)\n",
	idle_mask[0], idle_mask[1]);
	} else {
	dev_dbg(hdev->dev, "closing kernel context\n");
	hdev->asic_funcs->ctx_fini(ctx);
	hl_vm_ctx_fini(ctx);
	hl_mmu_ctx_fini(ctx);
	}
	}

	void hl_ctx_do_release(struct kref *ref)
	{
	struct hl_ctx *ctx;

	ctx = container_of(ref, struct hl_ctx, refcount);

	hl_ctx_fini(ctx);

	if (ctx->hpriv)
	hl_hpriv_put(ctx->hpriv);

	kfree(ctx);
	}

	int hl_ctx_create(struct hl_device hdev, struct hl_fpriv hpriv)
	{
	struct hl_ctx_mgr *mgr = &hpriv->ctx_mgr;
	struct hl_ctx *ctx;
	int rc;

	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
	if (!ctx) {
	rc = -ENOMEM;
	goto out_err;
	}

	mutex_lock(&mgr->ctx_lock);
	rc = idr_alloc(&mgr->ctx_handles, ctx, 1, 0, GFP_KERNEL);
	mutex_unlock(&mgr->ctx_lock);

	if (rc < 0) {
	dev_err(hdev->dev, "Failed to allocate IDR for a new CTX\n");
	goto free_ctx;
	}

	ctx->handle = rc;

	rc = hl_ctx_init(hdev, ctx, false);
	if (rc)
	goto remove_from_idr;

	hl_hpriv_get(hpriv);
	ctx->hpriv = hpriv;

	/* TODO: remove for multiple contexts per process */
	hpriv->ctx = ctx;

	/* TODO: remove the following line for multiple process support */
	hdev->compute_ctx = ctx;

	return 0;

	remove_from_idr:
	mutex_lock(&mgr->ctx_lock);
	idr_remove(&mgr->ctx_handles, ctx->handle);
	mutex_unlock(&mgr->ctx_lock);
	free_ctx:
	kfree(ctx);
	out_err:
	return rc;
	}

	void hl_ctx_free(struct hl_device hdev, struct hl_ctx ctx)
	{
	if (kref_put(&ctx->refcount, hl_ctx_do_release) == 1)
	return;

	dev_warn(hdev->dev,
	"user process released device but its command submissions are still executing\n");
	}

	int hl_ctx_init(struct hl_device hdev, struct hl_ctx ctx, bool is_kernel_ctx)
	{
	int rc = 0;

	ctx->hdev = hdev;

	kref_init(&ctx->refcount);

	ctx->cs_sequence = 1;
	INIT_LIST_HEAD(&ctx->pending_cb_list);
	spin_lock_init(&ctx->pending_cb_lock);
	spin_lock_init(&ctx->cs_lock);
	atomic_set(&ctx->thread_ctx_switch_token, 1);
	atomic_set(&ctx->thread_pending_cb_token, 1);
	ctx->thread_ctx_switch_wait_token = 0;
	ctx->cs_pending = kcalloc(hdev->asic_prop.max_pending_cs,
	sizeof(struct hl_fence *),
	GFP_KERNEL);
	if (!ctx->cs_pending)
	return -ENOMEM;

	if (is_kernel_ctx) {
	ctx->asid = HL_KERNEL_ASID_ID; /* Kernel driver gets ASID 0 */
	rc = hl_vm_ctx_init(ctx);
	if (rc) {
	dev_err(hdev->dev, "Failed to init mem ctx module\n");
	rc = -ENOMEM;
	goto err_free_cs_pending;
	}

	rc = hdev->asic_funcs->ctx_init(ctx);
	if (rc) {
	dev_err(hdev->dev, "ctx_init failed\n");
	goto err_vm_ctx_fini;
	}
	} else {
	ctx->asid = hl_asid_alloc(hdev);
	if (!ctx->asid) {
	dev_err(hdev->dev, "No free ASID, failed to create context\n");
	rc = -ENOMEM;
	goto err_free_cs_pending;
	}

	rc = hl_vm_ctx_init(ctx);
	if (rc) {
	dev_err(hdev->dev, "Failed to init mem ctx module\n");
	rc = -ENOMEM;
	goto err_asid_free;
	}

	rc = hl_cb_va_pool_init(ctx);
	if (rc) {
	dev_err(hdev->dev,
	"Failed to init VA pool for mapped CB\n");
	goto err_vm_ctx_fini;
	}

	rc = hdev->asic_funcs->ctx_init(ctx);
	if (rc) {
	dev_err(hdev->dev, "ctx_init failed\n");
	goto err_cb_va_pool_fini;
	}

	dev_dbg(hdev->dev, "create user context %d\n", ctx->asid);
	}

	return 0;

	err_cb_va_pool_fini:
	hl_cb_va_pool_fini(ctx);
	err_vm_ctx_fini:
	hl_vm_ctx_fini(ctx);
	err_asid_free:
	if (ctx->asid != HL_KERNEL_ASID_ID)
	hl_asid_free(hdev, ctx->asid);
	err_free_cs_pending:
	kfree(ctx->cs_pending);

	return rc;
	}

	void hl_ctx_get(struct hl_device hdev, struct hl_ctx ctx)
	{
	kref_get(&ctx->refcount);
	}

	int hl_ctx_put(struct hl_ctx *ctx)
	{
	return kref_put(&ctx->refcount, hl_ctx_do_release);
	}

	struct hl_fence hl_ctx_get_fence(struct hl_ctx ctx, u64 seq)
	{
	struct asic_fixed_properties *asic_prop = &ctx->hdev->asic_prop;
	struct hl_fence *fence;

	spin_lock(&ctx->cs_lock);

	if (seq >= ctx->cs_sequence) {
	spin_unlock(&ctx->cs_lock);
	return ERR_PTR(-EINVAL);
	}

	if (seq + asic_prop->max_pending_cs < ctx->cs_sequence) {
	spin_unlock(&ctx->cs_lock);
	return NULL;
	}

	fence = ctx->cs_pending[seq & (asic_prop->max_pending_cs - 1)];
	hl_fence_get(fence);

	spin_unlock(&ctx->cs_lock);

	return fence;
	}

	/*
	* hl_ctx_mgr_init - initialize the context manager
	*
	* @mgr: pointer to context manager structure
	*
	* This manager is an object inside the hpriv object of the user process.
	* The function is called when a user process opens the FD.
	*/
	void hl_ctx_mgr_init(struct hl_ctx_mgr *mgr)
	{
	mutex_init(&mgr->ctx_lock);
	idr_init(&mgr->ctx_handles);
	}

	/*
	* hl_ctx_mgr_fini - finalize the context manager
	*
	* @hdev: pointer to device structure
	* @mgr: pointer to context manager structure
	*
	* This function goes over all the contexts in the manager and frees them.
	* It is called when a process closes the FD.
	*/
	void hl_ctx_mgr_fini(struct hl_device hdev, struct hl_ctx_mgr mgr)
	{
	struct hl_ctx *ctx;
	struct idr *idp;
	u32 id;

	idp = &mgr->ctx_handles;

	idr_for_each_entry(idp, ctx, id)
	hl_ctx_free(hdev, ctx);

	idr_destroy(&mgr->ctx_handles);
	mutex_destroy(&mgr->ctx_lock);
	}