From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from MRWPR03CU001.outbound.protection.outlook.com (mail-francesouthazon11011006.outbound.protection.outlook.com [40.107.130.6]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5B57D381B04; Mon, 20 Apr 2026 06:14:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.107.130.6 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776665644; cv=fail; b=W8I4H01XEoly1RNNlIJpnLb/upGGcKmwG6Qv7ztpqWhE32x7nVQvwJLSgri5d5RlcGtgjvvNBaQ8DkR3iD5F5KN44khxLUp1JVV71bHi0xGQlH1jySL4B5v0FBEXjG1a2huyJE9KwklUkRYHk6O7w5s+4yeSsH7JgZcuZseYxoQ= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776665644; c=relaxed/simple; bh=HKaj4yAHDV2BwjRaImtX2btqmm3KFXaXqok84kV71yQ=; h=Date:From:To:Cc:Subject:Message-ID:References:Content-Type: Content-Disposition:In-Reply-To:MIME-Version; b=VqRTDOTIvBU6FIR4UiD5kYMV/26kYAmsFSsPvdwEodSjuTxLzn7/VOWVPVUHR4wGW+uBI06sv8R0wL4gFgD5T70ueX64C870IRoc3MiG2HhTP37uUcQYcqGZC0vbyzZBk8cmmUCroPTusweokNR50GPvF1sMcGFgJOZ6yJSOjzY= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=nxp.com; spf=pass smtp.mailfrom=nxp.com; dkim=pass (2048-bit key) header.d=nxp.com header.i=@nxp.com header.b=Yn0Ps4DF; arc=fail smtp.client-ip=40.107.130.6 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=nxp.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=nxp.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=nxp.com header.i=@nxp.com header.b="Yn0Ps4DF" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=hVV6/PuLx1ot1TaLpFHSoZq0SIYcWKKtC81mTMMiCZW0IIRsv2Qqm4GRJcds1iaOT+yjgmCdamhl9NpMV710uEvu4RFETp7us+RGvue5AuAcwHxUG/Eg+a8ZtTH/EzFgYcvP8wMi384hkMgMgbnaNPCjvTlHzYbKrVvSrQ+RLCf7xxAdvqX4dx6ciYojeDsmqjA95bjulzw9j/bGrze4UoDQVHpPa/jLkdbM3112papf3gEjwEyEok7k0iMjSlgOKBVi67sKm0BCXdLfNNazl4jKUCX0Xg7a4ObwqJmOhvq360GoeezyTWb7NrWYUpPathJefTxGOR9GQJE6yl8cPg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=Qx996Mz1uWp1syR8Rw8iuDODn+PEmStYYBL+mMsP6p4=; b=yRX0hlYS60qtBAKcqYJZ0MWObMQka0xw49NvAJQJ3flobbTkZzGAM++rf6wNORQhqUfAIFFD8ucR8JDpjuM9JRphQeXQg34Wt6Qu506S5H72eHl5x3/ttaGZhxf5S9YtwHI+JOya7n1RjGDpf9UP6sGH0n4Y83hM/IPtsi9q8VKSjP7H6/8DgNaAdqaM3pku8WVh3O0OLkS5phCF+Qmq3zemIhBRVW259/H6+rbWkidBfeT53tl4VWP49q09jPxNupoFEHmb5XUoPSOvNTdgsKW+Tvl8g1knA7kVAHy0QbM/6olRo0SeErjA0YO7aAnD0DgBzzyQJ9VVDYE9BY0+zw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nxp.com; dmarc=pass action=none header.from=nxp.com; dkim=pass header.d=nxp.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nxp.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=Qx996Mz1uWp1syR8Rw8iuDODn+PEmStYYBL+mMsP6p4=; b=Yn0Ps4DFtZUlNd4U0qLQgtjr8qGMyWp6eSXiYlufCiOUqQJTsOgymS032wHspPAjuxqkK9zmapkmKGpZR6KJjKN0hxGpxzoynIEaWnfkaJLmIuDY08E19eCsN/iDN1HZnM/LhdCm9oZWK5GpOvDxYPVJ+AX+tbHr2obDhhRgHYAsLJaXNibgxEgAIUqNKXqS6O4AKB12+Hay7aFFGuJniV9+/kAncul/XSW7fqJ9pc2myP2yJ92peBMv28LbZAcnhNbq85rw5gFg5Ija18GVLpLpFY3fphiC8DjgZEfggxJnO/FpNXpACfms39LHjXnl7tdlGeGGflZHeyA6m9wbpA== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=nxp.com; Received: from PA4PR04MB9366.eurprd04.prod.outlook.com (2603:10a6:102:2a9::8) by PR3PR04MB7467.eurprd04.prod.outlook.com (2603:10a6:102:80::20) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9818.21; Mon, 20 Apr 2026 06:13:57 +0000 Received: from PA4PR04MB9366.eurprd04.prod.outlook.com ([fe80::75e4:8143:ddbc:6588]) by PA4PR04MB9366.eurprd04.prod.outlook.com ([fe80::75e4:8143:ddbc:6588%6]) with mapi id 15.20.9818.032; Mon, 20 Apr 2026 06:13:56 +0000 Date: Mon, 20 Apr 2026 02:13:52 -0400 From: Frank Li To: Rosen Penev Cc: dmaengine@vger.kernel.org, Andy Shevchenko , Vinod Koul , Frank Li , Kees Cook , "Gustavo A. R. Silva" , "open list:INTEL MID (Mobile Internet Device) PLATFORM" , "open list:KERNEL HARDENING (not covered by other areas):Keyword:b__counted_by(_le|_be)?b" Subject: Re: [PATCHv4] dmaengine: hsu: use kzalloc_flex() Message-ID: References: <20260415032753.6006-1-rosenp@gmail.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260415032753.6006-1-rosenp@gmail.com> X-ClientProxiedBy: FR2P281CA0106.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:9c::18) To PA4PR04MB9366.eurprd04.prod.outlook.com (2603:10a6:102:2a9::8) Precedence: bulk X-Mailing-List: dmaengine@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PA4PR04MB9366:EE_|PR3PR04MB7467:EE_ X-MS-Office365-Filtering-Correlation-Id: 69558810-1aff-4aa0-a5be-08de9ea4013a X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|19092799006|1800799024|52116014|376014|366016|56012099003|22082099003|18002099003|38350700014; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:PA4PR04MB9366.eurprd04.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(19092799006)(1800799024)(52116014)(376014)(366016)(56012099003)(22082099003)(18002099003)(38350700014);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?Ih2fzQ9yfJoEFyVEP7gU9G+cHnEb1j9owQa6TDvkDVjqbzmK+FMB/r38HTAn?= =?us-ascii?Q?tpxuPQ6HVjjsXGFoqBX8oQNAA2Fi73oDfGjhkgmoRXst81doHtC0Ud8nGi0j?= =?us-ascii?Q?boGLfG6FimQmbuMk9owgvwVy749npxnv73E7s5/zCBay4rnF/TaQJtSor1d2?= =?us-ascii?Q?KtEQODcBb3DPwShas9cKGchKxLwyDq4INDecoY2cax9g6PWguxcQFb0ygag/?= =?us-ascii?Q?W70z1wQ8bSJCe6PkkDzkONN2jk1b+KMNVHkbHsluwgG2vsCro83yhTbXbK6A?= =?us-ascii?Q?zSviiTmtVAcoaVqT+Uo/CC1wMAznbnWR4b0Saaus14zrSFrqHSjiZ7godPS4?= =?us-ascii?Q?y14CFJJXZtDf/6DLL8rmmIVuafpf9U82ZHI7kbM9DvU+WkF03i1dcuRqs70Z?= =?us-ascii?Q?hcB5jdiLDJ4A9b5vrgn0KDa1QiqFrYUgCz2iZiIgLPvemxICDXCvzCP8Bsi/?= =?us-ascii?Q?Km+BGUd4C1PlxWKYcHolMBODikFY/FAKr7JLy9ERvdKFYYsKTdlAoCTBXzL+?= =?us-ascii?Q?6ETzy6LXWGvdmjRbrLQV8tPfWmlAChWyz0QzjAEyXKEl2oCGFpChetEa1GHJ?= =?us-ascii?Q?Ahq+jiT+0x8SZi3MbOhJSu5s09CPAkMEokaNelXMM0tt8DLpT5Qk7a0Zo9dp?= =?us-ascii?Q?3v645KkyGgJWqewhZYtOvI5cLx/XzvLHWxxyZAjotNbxdGNy421Z09huPP/y?= =?us-ascii?Q?S3hHN0tgk9WEjVtEvagZtbEC6QG3ehuDfh4o1dXQNnCvv89vq7gmmKmANQIT?= =?us-ascii?Q?28jAUMTqhVHoUu8IMvfmHMsLdmSWT4V4ejuVk6gVLhySDZZZzn5zfCaCM/Xg?= =?us-ascii?Q?WnakjZf+rpXpXsChUzzu+o/IRALFBJXURg1HVHabORqXXtRQEJggUIZDiBtD?= =?us-ascii?Q?/EtsVPoXQ25q0p/s8Sw1qTvgPfRFTaQHJzb09X+eAcfTzur+7EeHtAy/Azzo?= =?us-ascii?Q?G/jK0kRABTejC2SHXR7C3IITym4duq4b9QDkx1o5qhtW7obyOrU8xPZs647P?= =?us-ascii?Q?+0typ8gGwfmKeyBBpnkBNCN7ij9lEhOyW7qA1lBpycaz+ZHZQWzZQYJ+TjTP?= =?us-ascii?Q?eYWJqldqHF3c6fDOHCTmzLHXPc6NPotcPqGfi6ELNYGhACvZ2VXc4GhiGmtf?= =?us-ascii?Q?g1Yvavi03jLd+V8lTtVI8VqWKdOk8YAU+uP8eFoMTVcQdElNEfTXxdIKVC/4?= =?us-ascii?Q?JjSlQwq/Q/Dw/LCCrH8D2g9a89Q5U0cFMvtBFfmeUnd6kuThEkXg0WILtNb/?= =?us-ascii?Q?5vh9XAf2MR0Z28t2XEfJ8oZH94Dn5e3N8sFAcAn4yDZXSyicJ/CdIYNVHgXg?= =?us-ascii?Q?0FjWLcaW3/sDgxLWjNpihMfzIa2d8U9XRQ5gTiIhPO1v6P9r3mTFo2+D8MnQ?= =?us-ascii?Q?YnbLddFD9LJezO02WmcBw3HVI7ZRqBBM1LAlJmpnI21H5hXDkObwDHT35edD?= =?us-ascii?Q?Jnsn0dLigOhN/kAzSxFiI0I8fCSrIv8HMbr1b6XPRls9NEJCke5OwF704nq0?= =?us-ascii?Q?wf8j07/goHAiJ8Y2vYL0cwr3IaxikM41rRFwN2tuXEsApu/Zfxb2sN46Ic4x?= =?us-ascii?Q?s/vhZfRB7I4f1EJnj+aWrlvLWFkNWvEFh1BAwptiRH8+NeO/LnjzZMdPGuml?= =?us-ascii?Q?YyRXmzzMCYX8fmNGEq/9wGDwCMV6h2q6jAAZrE0V2jU5rloiVTIXcezaPaAD?= =?us-ascii?Q?QXxa6huld/cwRk5DykAyglbb+X6k+nU6COBFnrgqiLwsPwPK?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: 69558810-1aff-4aa0-a5be-08de9ea4013a X-MS-Exchange-CrossTenant-AuthSource: PA4PR04MB9366.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Apr 2026 06:13:56.8297 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: rrExOAut17FpETJ6UOni3E0vVGz9yHLaSrEYy5EtiqVRpUA/jBWmjtPUT67tWY2OPf0PLaX8kNNyP7Xos9vEsQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PR3PR04MB7467 Subject dmaengine: hsu: use kzalloc_flex() to simplify code On Tue, Apr 14, 2026 at 08:27:53PM -0700, Rosen Penev wrote: > Simplifies allocations by using a flexible array member in this struct. %s/this struct/struct hsu_dma_sg and struct hsu_dma. Frank > > Remove hsu_dma_alloc_desc(). It now offers no readability advantages in > this single usage. > > Add __counted_by to get extra runtime analysis. > > Apply the exact same treatment to struct hsu_dma and devm_kzalloc(). > > Signed-off-by: Rosen Penev > --- > v4: move back counting variable assignment, as requested. > v3: update description. > v2: address review comments. > drivers/dma/hsu/hsu.c | 43 +++++++++++-------------------------------- > drivers/dma/hsu/hsu.h | 4 ++-- > 2 files changed, 13 insertions(+), 34 deletions(-) > > diff --git a/drivers/dma/hsu/hsu.c b/drivers/dma/hsu/hsu.c > index f62d60d7bc6b..b1dd4fd1109b 100644 > --- a/drivers/dma/hsu/hsu.c > +++ b/drivers/dma/hsu/hsu.c > @@ -241,28 +241,10 @@ int hsu_dma_do_irq(struct hsu_dma_chip *chip, unsigned short nr, u32 status) > } > EXPORT_SYMBOL_GPL(hsu_dma_do_irq); > > -static struct hsu_dma_desc *hsu_dma_alloc_desc(unsigned int nents) > -{ > - struct hsu_dma_desc *desc; > - > - desc = kzalloc_obj(*desc, GFP_NOWAIT); > - if (!desc) > - return NULL; > - > - desc->sg = kzalloc_objs(*desc->sg, nents, GFP_NOWAIT); > - if (!desc->sg) { > - kfree(desc); > - return NULL; > - } > - > - return desc; > -} > - > static void hsu_dma_desc_free(struct virt_dma_desc *vdesc) > { > struct hsu_dma_desc *desc = to_hsu_dma_desc(vdesc); > > - kfree(desc->sg); > kfree(desc); > } > > @@ -276,10 +258,15 @@ static struct dma_async_tx_descriptor *hsu_dma_prep_slave_sg( > struct scatterlist *sg; > unsigned int i; > > - desc = hsu_dma_alloc_desc(sg_len); > + desc = kzalloc_flex(*desc, sg, sg_len, GFP_NOWAIT); > if (!desc) > return NULL; > > + desc->nents = sg_len; > + desc->direction = direction; > + /* desc->active = 0 by kzalloc */ > + desc->status = DMA_IN_PROGRESS; > + > for_each_sg(sgl, sg, sg_len, i) { > desc->sg[i].addr = sg_dma_address(sg); > desc->sg[i].len = sg_dma_len(sg); > @@ -287,11 +274,6 @@ static struct dma_async_tx_descriptor *hsu_dma_prep_slave_sg( > desc->length += sg_dma_len(sg); > } > > - desc->nents = sg_len; > - desc->direction = direction; > - /* desc->active = 0 by kzalloc */ > - desc->status = DMA_IN_PROGRESS; > - > return vchan_tx_prep(&hsuc->vchan, &desc->vdesc, flags); > } > > @@ -428,22 +410,19 @@ int hsu_dma_probe(struct hsu_dma_chip *chip) > { > struct hsu_dma *hsu; > void __iomem *addr = chip->regs + chip->offset; > + unsigned short nr_channels; > unsigned short i; > int ret; > > - hsu = devm_kzalloc(chip->dev, sizeof(*hsu), GFP_KERNEL); > + /* Calculate nr_channels from the IO space length */ > + nr_channels = (chip->length - chip->offset) / HSU_DMA_CHAN_LENGTH; > + hsu = devm_kzalloc(chip->dev, struct_size(hsu, chan, nr_channels), GFP_KERNEL); > if (!hsu) > return -ENOMEM; > > chip->hsu = hsu; > > - /* Calculate nr_channels from the IO space length */ > - hsu->nr_channels = (chip->length - chip->offset) / HSU_DMA_CHAN_LENGTH; > - > - hsu->chan = devm_kcalloc(chip->dev, hsu->nr_channels, > - sizeof(*hsu->chan), GFP_KERNEL); > - if (!hsu->chan) > - return -ENOMEM; > + hsu->nr_channels = nr_channels; > > INIT_LIST_HEAD(&hsu->dma.channels); > for (i = 0; i < hsu->nr_channels; i++) { > diff --git a/drivers/dma/hsu/hsu.h b/drivers/dma/hsu/hsu.h > index 3bca577b98a1..f6ca1014bccf 100644 > --- a/drivers/dma/hsu/hsu.h > +++ b/drivers/dma/hsu/hsu.h > @@ -71,11 +71,11 @@ struct hsu_dma_sg { > struct hsu_dma_desc { > struct virt_dma_desc vdesc; > enum dma_transfer_direction direction; > - struct hsu_dma_sg *sg; > unsigned int nents; > size_t length; > unsigned int active; > enum dma_status status; > + struct hsu_dma_sg sg[] __counted_by(nents); > }; > > static inline struct hsu_dma_desc *to_hsu_dma_desc(struct virt_dma_desc *vdesc) > @@ -115,8 +115,8 @@ struct hsu_dma { > struct dma_device dma; > > /* channels */ > - struct hsu_dma_chan *chan; > unsigned short nr_channels; > + struct hsu_dma_chan chan[] __counted_by(nr_channels); > }; > > static inline struct hsu_dma *to_hsu_dma(struct dma_device *ddev) > -- > 2.53.0 >