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 B0A71CCD190 for ; Tue, 14 Oct 2025 07:13:59 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 6C9F810E555; Tue, 14 Oct 2025 07:13:59 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="LysmJff3"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.9]) by gabe.freedesktop.org (Postfix) with ESMTPS id E8A8310E553; Tue, 14 Oct 2025 07:13:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1760426038; x=1791962038; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=yh1xtuPzPIYwf/mvsxOCmqZavj42ErFHrTFWR7mOTeI=; b=LysmJff3wV8xg4CsVSCjrHmxmj+WUBFTM6sEcvbs35JaADPV/kP6iDmo yOP7aFyDOubr28k3TUUoQdS6vqEOfQSm0sFSZd21Agj7r7+7aIylVYoIQ VISzc+MzVa3cthlI/zXRrlglGJcaeg8tUAn+/ni3YwxCGebrJoIjA8kwI OAtk7K2+LL3xpdgSsf0pLAuWCg2yGGTGgwKEPeUpvIVZH3GxAPZY3ohUv JRmWDfEosjJSGqgR/O70Z7Vdk7Rz8oJxuRCboDwj6LCyrRY9S++gzRR8f 4I1thjmpgOfdX54c4MqEoj7IUYp95ZZ0SXAeyvl5nz+HvpK+n3jELaFk1 w==; X-CSE-ConnectionGUID: dJhTh38RSlGl+nR5BthR4A== X-CSE-MsgGUID: ItKirdGpSPajOk6hd2IebQ== X-IronPort-AV: E=McAfee;i="6800,10657,11581"; a="73257116" X-IronPort-AV: E=Sophos;i="6.19,227,1754982000"; d="scan'208";a="73257116" Received: from orviesa009.jf.intel.com ([10.64.159.149]) by fmvoesa103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Oct 2025 00:13:57 -0700 X-CSE-ConnectionGUID: oGfti8sAQ5+vzaf8oPTL4A== X-CSE-MsgGUID: ZE8b/suBRJK8pUA3alJ+8A== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.19,227,1754982000"; d="scan'208";a="181369856" Received: from vkasired-desk2.fm.intel.com ([10.105.128.132]) by orviesa009-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Oct 2025 00:13:57 -0700 From: Vivek Kasireddy To: dri-devel@lists.freedesktop.org, intel-xe@lists.freedesktop.org, linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org Cc: Vivek Kasireddy , Jason Gunthorpe , Christian Koenig , Sumit Semwal , =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , Simona Vetter Subject: [RFC 2/8] dma-buf: Add a helper to match interconnects between exporter/importer Date: Tue, 14 Oct 2025 00:08:52 -0700 Message-ID: <20251014071243.811884-3-vivek.kasireddy@intel.com> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20251014071243.811884-1-vivek.kasireddy@intel.com> References: <20251014071243.811884-1-vivek.kasireddy@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" If the importer provides an op for supports_interconnects(), the exporter starts the matching (or negotiation) process (during attach) by invoking the supports_interconnects() which would then call this helper to identify the first common interconnect supported by both exporter and importer. Note that whether an interconnect is supported between an exporter/importer is ultimately determined by the exporter via the match op it is expected to provide. Cc: Jason Gunthorpe Cc: Christian Koenig Cc: Sumit Semwal Cc: Thomas Hellström Cc: Simona Vetter Signed-off-by: Vivek Kasireddy --- drivers/dma-buf/dma-buf.c | 45 +++++++++++++++++++++++++++- include/linux/dma-buf-interconnect.h | 6 ++++ include/linux/dma-buf.h | 9 ++++++ 3 files changed, 59 insertions(+), 1 deletion(-) diff --git a/drivers/dma-buf/dma-buf.c b/drivers/dma-buf/dma-buf.c index 162642bd53e8..ed48540d1c1d 100644 --- a/drivers/dma-buf/dma-buf.c +++ b/drivers/dma-buf/dma-buf.c @@ -965,8 +965,11 @@ dma_buf_dynamic_attach(struct dma_buf *dmabuf, struct device *dev, attach->dev = dev; attach->dmabuf = dmabuf; - if (importer_ops) + if (importer_ops) { attach->peer2peer = importer_ops->allow_peer2peer; + if (importer_ops->supports_interconnects) + attach->allow_ic = true; + } attach->importer_ops = importer_ops; attach->importer_priv = importer_priv; @@ -1680,6 +1683,46 @@ void dma_buf_unmap_interconnect(struct dma_buf_attachment *attach, } EXPORT_SYMBOL_NS_GPL(dma_buf_unmap_interconnect, "DMA_BUF"); +bool dma_buf_match_interconnects(struct dma_buf_attachment *attach, + const struct dma_buf_interconnect_match *exp, + unsigned int exp_ics, + const struct dma_buf_interconnect_match *imp, + unsigned int imp_ics) +{ + const struct dma_buf_interconnect *exp_ic, *imp_ic; + const struct dma_buf_interconnect_ops *ic_ops; + struct dma_buf *dmabuf = attach->dmabuf; + unsigned int i, j; + + if (!exp || !imp) + return false; + + if (!attach->allow_ic) + return false; + + ic_ops = dmabuf->ops->interconnect_ops; + if (!ic_ops || !ic_ops->match_interconnect) + return false; + + for (i = 0; i < exp_ics; i++) { + for (j = 0; j < imp_ics; j++) { + exp_ic = exp[i].interconnect; + imp_ic = imp[j].interconnect; + + if (exp_ic->type == imp_ic->type) { + if (ic_ops->match_interconnect(exp_ic, imp_ic)) { + attach->interconnect.type = exp_ic->type; + return true; + } + } + } + } + + attach->allow_ic = false; + return false; +} +EXPORT_SYMBOL_NS_GPL(dma_buf_match_interconnects, "DMA_BUF"); + #ifdef CONFIG_DEBUG_FS static int dma_buf_debug_show(struct seq_file *s, void *unused) { diff --git a/include/linux/dma-buf-interconnect.h b/include/linux/dma-buf-interconnect.h index 17504dea9691..a72f65ed4806 100644 --- a/include/linux/dma-buf-interconnect.h +++ b/include/linux/dma-buf-interconnect.h @@ -20,10 +20,16 @@ struct dma_buf_interconnect { enum dma_buf_interconnect_type type; }; +struct dma_buf_interconnect_match { + const struct dma_buf_interconnect *interconnect; +}; + struct dma_buf_interconnect_ops { int (*map_interconnect)(struct dma_buf_attachment *attach, struct dma_buf_ranges *ranges); void (*unmap_interconnect)(struct dma_buf_attachment *attach, struct dma_buf_ranges *ranges); + bool (*match_interconnect)(const struct dma_buf_interconnect *exp_ic, + const struct dma_buf_interconnect *imp_ic); }; #endif diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index db91c67c00d6..3e6124387f3c 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -479,6 +479,10 @@ struct dma_buf_attach_ops { * point to the new location of the DMA-buf. */ void (*move_notify)(struct dma_buf_attachment *attach); + + bool (*supports_interconnects)(struct dma_buf_attachment *attach, + const struct dma_buf_interconnect_match *, + unsigned int num_ics); }; /** @@ -599,6 +603,11 @@ void dma_buf_unmap_attachment(struct dma_buf_attachment *, struct sg_table *, struct dma_buf_ranges *dma_buf_map_interconnect(struct dma_buf_attachment *); void dma_buf_unmap_interconnect(struct dma_buf_attachment *, struct dma_buf_ranges *); +bool dma_buf_match_interconnects(struct dma_buf_attachment *attach, + const struct dma_buf_interconnect_match *, + unsigned int exp_ics, + const struct dma_buf_interconnect_match *, + unsigned int imp_ics); void dma_buf_move_notify(struct dma_buf *dma_buf); int dma_buf_begin_cpu_access(struct dma_buf *dma_buf, -- 2.50.1