From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qt1-f174.google.com (mail-qt1-f174.google.com [209.85.160.174]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8E8DD37474B for ; Tue, 7 Apr 2026 03:51:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.160.174 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775533914; cv=none; b=qIBLw1uZB7xFYj4gnHpQXx3+acQQOdAA50W5ovUJzL9aR+kcIvxvMOSreD2BwjkeR2+eTg2tdE1oeafh+4mnWkA9bIChmnWHbKfdOfbaCgO7ghk9Os+ZETgO9+ZYyznpQOaelxSHYpzzIoIJzXTFjmgh20zPxlJsWiIPzeJY4jc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775533914; c=relaxed/simple; bh=ZGc+Lx7Q3ImjQIU2MsaptvUr2OjdQPH11+1aygZf1BQ=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=eTkEMuHEJ2bhaiiSqvkNVZuUG82EzbPSensFKJ8j9+02yAIyCNrahvIt8OHXxcJzqmYI1j1eujswXJVD2ApUMjLTaEFzQ1YRNGJvk5cM4MY+wHrrGe8vzZ05V1Nz32zWJmami7ulXfR1AiLClRRN7mrJchQ/++xuNQHDdFsWxb4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=qsFa1Rns; arc=none smtp.client-ip=209.85.160.174 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="qsFa1Rns" Received: by mail-qt1-f174.google.com with SMTP id d75a77b69052e-50d6b9bca48so58729051cf.2 for ; Mon, 06 Apr 2026 20:51:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1775533912; x=1776138712; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=e/TQHykLdF85VtC6CTJ2wonciXUmXtr/iGFz2p1d+iM=; b=qsFa1RnsmqIpoiWveTXijEroCfY6YDbyuRPmq/j8gurUFF5XxOJxSbR1N7RGlYfIaO DpGxIT4WTWgDfVRGHTJPimjw3DMyu8s7rXdK3jfGA2bvl2mMv0NlnsR1fYiO/A8rrKbm ghYcVrv2sYteen6K4Cin73OGtBcuL3JI90fjf3Oyvs0UbWkgYky8a0lyzwVJ4cgZ/7PU WiS2vOaxD2k06Bsbh/eMdx3EJoKEHRMMG80lq0jFodWnuysiAZkew3lXj/ryMDgjDwwH 153d67gnK29wOno2xZueGHfUKdQ7KKL6H6BlqASEtybnG4B7dys38XZr88tGWa3eieN5 K2aw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1775533912; x=1776138712; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=e/TQHykLdF85VtC6CTJ2wonciXUmXtr/iGFz2p1d+iM=; b=pc8YQEEkXaxklkjNmFULvIAF2fOoL7BBNVh3xTKd7wZt7SQ2izl96ZBa1Fr3i+I2Oi O1wZ+faoBV171ciRQcAqLAwsdiWcJtYg9MHRyd9dJMdnkjfkZ43kLxv5wrrApERuFXtU smXYk/+7rGQyjS0pcTHCKllJZ/C/Hxhb7tVUvw8WKbkUjAKYyoE5YVAbD2RYXeJPLJ7G EKWJyRKF+rnZr6zkWrDUhO6OXWQwfFkdvMjQT5f+sy9N5GhdCa1EsWbQQ2MS2AhkegGl IIGBNOJ2rSNo2+SetXM0msp258uULufPL44Ux5oyIzJ9IIs/+1NzDHwISfjyt9hTX5sX cLnQ== X-Gm-Message-State: AOJu0Yxho68Q1y1sdhqLqd0lfh9PZ7axPEvp6c/kuwGSWnBbGAiaFJ40 1L8OGEx06hiEtWWBOyKyj0g9bYxudM34pf+5FWsCF7aS0wyLpGetv0MuiWCnUw== X-Gm-Gg: AeBDiesXqqqd17J8aDI66HQ/Lw0En1fkNDc1EYx/dDhmEcL3AVLlV/LZXzFC8paO1dg 3M4tfZkCHfAfEUbDn6mBbttaX+dRlGHdY5dzEpum+XFWXS/ECTH/1CveVv6EshMqAOQ6AVJwlOj os0wX4QpRfFiuzv9o8YbQgCVfFrHcmCFfSNiXQ/R1lnsmoBnacntsIqNG+9bU6UlymwPsDd8H/H A7O8gWCaF4ZiY+nJXdbaua+a1kJYEQNb+NxhBBYJgiVCnRIlXSrcDQBzh2Cl6qGZn3NpzLmfGIG KztZ2bCBUXB+ogbGU1WKvLXNCyD7f/9yWmFOsKmsJLt3fRBejZtC7UiTywPQrEa8kq8kXmf7AfX xzO3uCjx8nEiEe/eyVbG37ME8OtRSUbwe8p81dtt5cbmkSf65Cd7hhSlocehJ78HgepkgFDk/uF nkfWHs6B80YcInQ7s39xD4JyXRDZbDZRU8XcvmDQT/yigL3G8Mb2EBEAk= X-Received: by 2002:a05:622a:1247:b0:50d:8389:c3f3 with SMTP id d75a77b69052e-50d8389c6c4mr146678471cf.54.1775533912203; Mon, 06 Apr 2026 20:51:52 -0700 (PDT) Received: from ryzen ([2601:644:8000:5b5d::8bd]) by smtp.gmail.com with ESMTPSA id d75a77b69052e-50d82afc7d5sm77280341cf.30.2026.04.06.20.51.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 06 Apr 2026 20:51:50 -0700 (PDT) From: Rosen Penev To: dmaengine@vger.kernel.org Cc: Vinod Koul , Frank Li , Vladimir Zapolskiy , Kees Cook , "Gustavo A. R. Silva" , linux-arm-kernel@lists.infradead.org (moderated list:ARM/LPC18XX ARCHITECTURE), linux-kernel@vger.kernel.org (open list), linux-hardening@vger.kernel.org (open list:KERNEL HARDENING (not covered by other areas):Keyword:\b__counted_by(_le|_be)?\b) Subject: [PATCH] dmaengine: lpc18xx-dmamux: simplify allocation Date: Mon, 6 Apr 2026 20:51:32 -0700 Message-ID: <20260407035132.99037-1-rosenp@gmail.com> X-Mailer: git-send-email 2.53.0 Precedence: bulk X-Mailing-List: dmaengine@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Use a flexible array member to combine allocations. Requires preparation, aka reshuffling before the actual allocation to get the proper size. Add __counted_by for extra runtime analysis. Signed-off-by: Rosen Penev --- drivers/dma/lpc18xx-dmamux.c | 42 +++++++++++++++++------------------- 1 file changed, 20 insertions(+), 22 deletions(-) diff --git a/drivers/dma/lpc18xx-dmamux.c b/drivers/dma/lpc18xx-dmamux.c index d3ff521951b8..5dfefbc496da 100644 --- a/drivers/dma/lpc18xx-dmamux.c +++ b/drivers/dma/lpc18xx-dmamux.c @@ -32,11 +32,11 @@ struct lpc18xx_dmamux { struct lpc18xx_dmamux_data { struct dma_router dmarouter; - struct lpc18xx_dmamux *muxes; u32 dma_master_requests; u32 dma_mux_requests; struct regmap *reg; spinlock_t lock; + struct lpc18xx_dmamux muxes[] __counted_by(dma_master_requests); }; static void lpc18xx_dmamux_free(struct device *dev, void *route_data) @@ -122,12 +122,30 @@ static int lpc18xx_dmamux_probe(struct platform_device *pdev) { struct device_node *dma_np, *np = pdev->dev.of_node; struct lpc18xx_dmamux_data *dmamux; + u32 dma_master_requests; int ret; - dmamux = devm_kzalloc(&pdev->dev, sizeof(*dmamux), GFP_KERNEL); + dma_np = of_parse_phandle(np, "dma-masters", 0); + if (!dma_np) { + dev_err(&pdev->dev, "can't get dma master\n"); + return -ENODEV; + } + + ret = of_property_read_u32(dma_np, "dma-requests", + &dma_master_requests); + of_node_put(dma_np); + if (ret) { + dev_err(&pdev->dev, "missing master dma-requests property\n"); + return ret; + } + + dmamux = devm_kzalloc(&pdev->dev, struct_size(dmamux, muxes, dma_master_requests), + GFP_KERNEL); if (!dmamux) return -ENOMEM; + dmamux->dma_master_requests = dma_master_requests; + dmamux->reg = syscon_regmap_lookup_by_compatible("nxp,lpc1850-creg"); if (IS_ERR(dmamux->reg)) { dev_err(&pdev->dev, "syscon lookup failed\n"); @@ -141,26 +159,6 @@ static int lpc18xx_dmamux_probe(struct platform_device *pdev) return ret; } - dma_np = of_parse_phandle(np, "dma-masters", 0); - if (!dma_np) { - dev_err(&pdev->dev, "can't get dma master\n"); - return -ENODEV; - } - - ret = of_property_read_u32(dma_np, "dma-requests", - &dmamux->dma_master_requests); - of_node_put(dma_np); - if (ret) { - dev_err(&pdev->dev, "missing master dma-requests property\n"); - return ret; - } - - dmamux->muxes = devm_kcalloc(&pdev->dev, dmamux->dma_master_requests, - sizeof(struct lpc18xx_dmamux), - GFP_KERNEL); - if (!dmamux->muxes) - return -ENOMEM; - spin_lock_init(&dmamux->lock); platform_set_drvdata(pdev, dmamux); dmamux->dmarouter.dev = &pdev->dev; -- 2.53.0