From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D7B7CD6E2AF for ; Thu, 18 Dec 2025 16:21:54 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 9605210EA39; Thu, 18 Dec 2025 16:21:54 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="LU76Vo4u"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.13]) by gabe.freedesktop.org (Postfix) with ESMTPS id EA7D810EA35; Thu, 18 Dec 2025 16:21:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1766074912; x=1797610912; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=+eCfLLO/iyR3BSyi+KnWpaGIfToysaMbgs9HtgEMacY=; b=LU76Vo4uTJJjGFxxgCKcMbYwROKSQxx03w3AbjlazSXglCVpGlN14p7d 94CM6n1eY6YDkjqkzAPfdbkJ3w21+VmXc6Ux+9SIzBCsQuhwTMqZzG5/1 9sCtXCxkYLgcrj++J2/yiwn9ve/6t/Ryvdj6cTGFTyDW8Z/OyQPGoVVhA cjbcWFrHQdPLjPffBICRV2tlJr80Vo6keHx8spuwBtf7AWMAvLw/MC5AP JurHYGHymDdvyyzU7lx5hSjXPtlcxtQ/tzmVPjcCuoYckDkJGUmfWiXn0 7dL0JZjGUmi5uoM8nfuO1bCIVcQBmvZR875pPEq811SlthDhg2vQ7kH5C g==; X-CSE-ConnectionGUID: CnbchczSR+eKMOqSUTVz9A== X-CSE-MsgGUID: FpNOdydPQQSAx8JL/ihxrw== X-IronPort-AV: E=McAfee;i="6800,10657,11646"; a="70607580" X-IronPort-AV: E=Sophos;i="6.21,158,1763452800"; d="scan'208";a="70607580" Received: from orviesa005.jf.intel.com ([10.64.159.145]) by fmvoesa107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Dec 2025 08:21:52 -0800 X-CSE-ConnectionGUID: MNZC7Z/qRUSsNk7rX7hMDA== X-CSE-MsgGUID: vHllccmhRRu3v0IIp9tW0A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,158,1763452800"; d="scan'208";a="203705576" Received: from dhhellew-desk2.ger.corp.intel.com (HELO fedora) ([10.245.244.93]) by orviesa005-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Dec 2025 08:21:49 -0800 From: =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= To: intel-xe@lists.freedesktop.org Cc: =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , Matthew Brost , dri-devel@lists.freedesktop.org, himal.prasad.ghimiray@intel.com, apopple@nvidia.com, airlied@gmail.com, Simona Vetter , felix.kuehling@amd.com, =?UTF-8?q?Christian=20K=C3=B6nig?= , dakr@kernel.org, "Mrozek, Michal" , Joonas Lahtinen Subject: [PATCH v5 05/24] drm/pagemap: Add a refcounted drm_pagemap backpointer to struct drm_pagemap_zdd Date: Thu, 18 Dec 2025 17:20:42 +0100 Message-ID: <20251218162101.605379-6-thomas.hellstrom@linux.intel.com> X-Mailer: git-send-email 2.51.1 In-Reply-To: <20251218162101.605379-1-thomas.hellstrom@linux.intel.com> References: <20251218162101.605379-1-thomas.hellstrom@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" To be able to keep track of drm_pagemap usage, add a refcounted backpointer to struct drm_pagemap_zdd. This will keep the drm_pagemap reference count from dropping to zero as long as there are drm_pagemap pages present in a CPU address space. Signed-off-by: Thomas Hellström Reviewed-by: Matthew Brost --- drivers/gpu/drm/drm_pagemap.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_pagemap.c b/drivers/gpu/drm/drm_pagemap.c index 87648a498a31..4cc57ced4993 100644 --- a/drivers/gpu/drm/drm_pagemap.c +++ b/drivers/gpu/drm/drm_pagemap.c @@ -63,6 +63,7 @@ * * @refcount: Reference count for the zdd * @devmem_allocation: device memory allocation + * @dpagemap: Refcounted pointer to the underlying struct drm_pagemap. * @device_private_page_owner: Device private pages owner * * This structure serves as a generic wrapper installed in @@ -75,11 +76,13 @@ struct drm_pagemap_zdd { struct kref refcount; struct drm_pagemap_devmem *devmem_allocation; + struct drm_pagemap *dpagemap; void *device_private_page_owner; }; /** * drm_pagemap_zdd_alloc() - Allocate a zdd structure. + * @dpagemap: Pointer to the underlying struct drm_pagemap. * @device_private_page_owner: Device private pages owner * * This function allocates and initializes a new zdd structure. It sets up the @@ -88,7 +91,7 @@ struct drm_pagemap_zdd { * Return: Pointer to the allocated zdd on success, ERR_PTR() on failure. */ static struct drm_pagemap_zdd * -drm_pagemap_zdd_alloc(void *device_private_page_owner) +drm_pagemap_zdd_alloc(struct drm_pagemap *dpagemap, void *device_private_page_owner) { struct drm_pagemap_zdd *zdd; @@ -99,6 +102,7 @@ drm_pagemap_zdd_alloc(void *device_private_page_owner) kref_init(&zdd->refcount); zdd->devmem_allocation = NULL; zdd->device_private_page_owner = device_private_page_owner; + zdd->dpagemap = drm_pagemap_get(dpagemap); return zdd; } @@ -128,6 +132,7 @@ static void drm_pagemap_zdd_destroy(struct kref *ref) struct drm_pagemap_zdd *zdd = container_of(ref, struct drm_pagemap_zdd, refcount); struct drm_pagemap_devmem *devmem = zdd->devmem_allocation; + struct drm_pagemap *dpagemap = zdd->dpagemap; if (devmem) { complete_all(&devmem->detached); @@ -135,6 +140,7 @@ static void drm_pagemap_zdd_destroy(struct kref *ref) devmem->ops->devmem_release(devmem); } kfree(zdd); + drm_pagemap_put(dpagemap); } /** @@ -367,7 +373,7 @@ int drm_pagemap_migrate_to_devmem(struct drm_pagemap_devmem *devmem_allocation, pagemap_addr = buf + (2 * sizeof(*migrate.src) * npages); pages = buf + (2 * sizeof(*migrate.src) + sizeof(*pagemap_addr)) * npages; - zdd = drm_pagemap_zdd_alloc(pgmap_owner); + zdd = drm_pagemap_zdd_alloc(devmem_allocation->dpagemap, pgmap_owner); if (!zdd) { err = -ENOMEM; goto err_free; -- 2.51.1