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R. Silva" , Heiko Stuebner , iommu@lists.linux.dev, Jean-Philippe Brucker , Jernej Skrabec , Jonathan Hunter , Joerg Roedel , Kees Cook , Konrad Dybcio , Krzysztof Kozlowski , Len Brown , linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-arm-msm@vger.kernel.org, linux-hardening@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-sunxi@lists.linux.dev, linux-tegra@vger.kernel.org, Lorenzo Pieralisi , Marek Szyprowski , Hector Martin , Matthias Brugger , Orson Zhai , "Rafael J. Wysocki" , Rob Clark , Robert Moore , Rob Herring , Robin Murphy , Samuel Holland , Sudeep Holla , Sven Peter , Thierry Reding , Krishna Reddy , virtualization@lists.linux.dev, Chen-Yu Tsai , Will Deacon , Yong Wu , Chunyan Zhang Cc: =?utf-8?q?Andr=C3=A9_Draszik?= , patches@lists.linux.dev Subject: [PATCH 17/30] iommu: Add iommu_fw_alloc_per_device_ids() Date: Wed, 29 Nov 2023 21:10:24 -0400 Message-ID: <17-v1-f82a05539a64+5042-iommu_fwspec_p2_jgg@nvidia.com> In-Reply-To: <0-v1-f82a05539a64+5042-iommu_fwspec_p2_jgg@nvidia.com> References: X-ClientProxiedBy: SA0PR11CA0133.namprd11.prod.outlook.com (2603:10b6:806:131::18) To LV2PR12MB5869.namprd12.prod.outlook.com (2603:10b6:408:176::16) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: LV2PR12MB5869:EE_|PH0PR12MB5484:EE_ X-MS-Office365-Filtering-Correlation-Id: d05d55fc-83fa-40da-adad-08dbf1412b80 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; 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:LV2PR12MB5869.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230031)(366004)(346002)(136003)(396003)(39860400002)(376002)(230922051799003)(451199024)(1800799012)(186009)(64100799003)(1191002)(8936002)(110136005)(8676002)(316002)(66556008)(4326008)(86362001)(66476007)(6486002)(478600001)(66946007)(41300700001)(36756003)(921008)(7416002)(7366002)(2906002)(7406005)(5660300002)(38100700002)(2616005)(6512007)(6506007)(6666004)(83380400001)(26005)(202311291699003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: 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 X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: d05d55fc-83fa-40da-adad-08dbf1412b80 X-MS-Exchange-CrossTenant-AuthSource: LV2PR12MB5869.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 30 Nov 2023 01:10:40.9994 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: aJMyQNqWZ/e4wRCik6bJ1jQSIxUV6HrStxdFZB1eOQs1MQv1EnzIX48OQ8PEU0V1 X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR12MB5484 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231129_171104_015442_91C1622D X-CRM114-Status: GOOD ( 24.22 ) X-BeenThere: linux-rockchip@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Upstream kernel work for Rockchip platforms List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+linux-rockchip=archiver.kernel.org@lists.infradead.org This helper can be called after iommu_of_get_single_iommu() to automatically extract the raw list of IDs. It can be used by drivers that expect to have a list of simple u32 IDs for a single IOMMU instance. The driver must provide a per-driver structure with a trailing flex array to hold the IDs. This helper will allocate the structure, size the ids flex array, and fill it in with data. Driver's should follow a typical pattern in their probe_device: struct tegra_smmu_device { struct tegra_smmu *smmu; unsigned int num_ids; u32 ids[] __counted_by(num_ids); }; smmu = iommu_of_get_single_iommu(pinf, &tegra_smmu_ops, 1, struct tegra_smmu, iommu); if (IS_ERR(smmu)) return ERR_CAST(smmu); smmu_device = iommu_fw_alloc_per_device_ids(pinf, smmu_device); if (IS_ERR(smmu_device)) return ERR_CAST(smmu_device); [..] dev_iommu_priv_set(dev, data); return &iommu->iommu; Signed-off-by: Jason Gunthorpe --- drivers/iommu/iommu.c | 21 ++++++++++++++ drivers/iommu/of_iommu.c | 21 +++++++++++++- include/linux/iommu-driver.h | 56 ++++++++++++++++++++++++++++++++++++ 3 files changed, 97 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index ca411ad14c1182..caf14a53ed1952 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -3067,6 +3067,27 @@ struct iommu_device *iommu_fw_finish_get_single(struct iommu_probe_info *pinf) return pinf->cached_iommu; } +/* + * This function shouldn't be called directly without a pretty good reason, + * prefer to structure the driver to use iommu_fw_alloc_per_device_ids() + * instead. + */ +int iommu_fw_get_u32_ids(struct iommu_probe_info *pinf, u32 *ids) +{ + if (WARN_ON(!pinf->get_u32_ids)) + return -EINVAL; + + /* + * We pre-parse a small number if IDs and keep it on the stack. If that + * isn't enough then just reparse again. + */ + if (pinf->num_ids > ARRAY_SIZE(pinf->cached_ids)) + return pinf->get_u32_ids(pinf, ids); + memcpy(ids, pinf->cached_ids, pinf->num_ids * sizeof(*ids)); + return 0; +} +EXPORT_SYMBOL_GPL(iommu_fw_get_u32_ids); + int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode, const struct iommu_ops *ops) { diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c index 8d5495f03dbbcb..6f6e442f899ded 100644 --- a/drivers/iommu/of_iommu.c +++ b/drivers/iommu/of_iommu.c @@ -332,10 +332,28 @@ static int parse_single_iommu(struct of_phandle_args *iommu_spec, void *_info) iommu = parse_iommu(info, iommu_spec); if (IS_ERR(iommu)) return PTR_ERR(iommu); - info->pinf->num_ids++; + iommu_fw_cache_id(info->pinf, iommu_spec->args[0]); return 0; } +static int parse_read_ids(struct of_phandle_args *iommu_spec, void *_info) +{ + struct parse_info *info = _info; + u32 *ids = info->priv; + + *ids = iommu_spec->args[0]; + info->priv = ids + 1; + return 0; +} + +static int iommu_of_get_u32_ids(struct iommu_probe_info *pinf, u32 *ids) +{ + struct parse_info info = { .pinf = pinf, .priv = ids }; + + return of_iommu_for_each_id(pinf->dev, pinf->of_master_np, + pinf->of_map_id, parse_read_ids, &info); +} + struct iommu_device *__iommu_of_get_single_iommu(struct iommu_probe_info *pinf, const struct iommu_ops *ops, int num_cells) @@ -353,6 +371,7 @@ struct iommu_device *__iommu_of_get_single_iommu(struct iommu_probe_info *pinf, pinf->of_map_id, parse_single_iommu, &info); if (err) return ERR_PTR(err); + pinf->get_u32_ids = iommu_of_get_u32_ids; return iommu_fw_finish_get_single(pinf); } EXPORT_SYMBOL_GPL(__iommu_of_get_single_iommu); diff --git a/include/linux/iommu-driver.h b/include/linux/iommu-driver.h index 622d6ad9056ce0..632c7b4a389abe 100644 --- a/include/linux/iommu-driver.h +++ b/include/linux/iommu-driver.h @@ -40,7 +40,9 @@ struct iommu_probe_info { struct iommu_device *cached_iommu; struct device_node *of_master_np; const u32 *of_map_id; + int (*get_u32_ids)(struct iommu_probe_info *pinf, u32 *ids); unsigned int num_ids; + u32 cached_ids[8]; bool defer_setup : 1; bool is_dma_configure : 1; bool cached_single_iommu : 1; @@ -123,6 +125,60 @@ static inline unsigned int iommu_of_num_ids(struct iommu_probe_info *pinf) return pinf->num_ids; } +unsigned int iommu_of_num_ids(struct iommu_probe_info *pinf); +int iommu_fw_get_u32_ids(struct iommu_probe_info *pinf, u32 *ids); + +static inline void iommu_fw_cache_id(struct iommu_probe_info *pinf, u32 id) +{ + if (pinf->num_ids < ARRAY_SIZE(pinf->cached_ids)) + pinf->cached_ids[pinf->num_ids] = id; + pinf->num_ids++; +} + +static inline void * +__iommu_fw_alloc_per_device_ids(struct iommu_probe_info *pinf, void *mem, + unsigned int num_ids, unsigned int *num_ids_p, + u32 *ids_p) +{ + int ret; + + if (!mem) + return ERR_PTR(-ENOMEM); + + ret = iommu_fw_get_u32_ids(pinf, ids_p); + if (ret) { + kfree(mem); + return ERR_PTR(ret); + } + + *num_ids_p = num_ids; + return mem; +} + +/** + * iommu_fw_alloc_per_device_ids - Allocate a per-device struct with ids + * @pinf: The iommu_probe_info + * @drv_struct: Name of a variable to a pointer of the driver structure + * + * Called by a driver during probe this helper allocates and initializes the + * driver struct that embeds the ids array with the trailing members: + * + * unsigned int num_ids; + * u32 ids[] __counted_by(num_ids); + * + * The helper allocates the driver struct with the right size flex array, + * and initializes both members. Returns the driver struct or ERR_PTR. + */ +#define iommu_fw_alloc_per_device_ids(pinf, drv_struct) \ + ({ \ + unsigned int num_ids = iommu_of_num_ids(pinf); \ + typeof(drv_struct) drv; \ + \ + drv = kzalloc(struct_size(drv, ids, num_ids), GFP_KERNEL); \ + drv = __iommu_fw_alloc_per_device_ids( \ + pinf, drv, num_ids, &drv->num_ids, drv->ids); \ + }) + /* * Used temporarily to indicate drivers that have moved to the new probe method. */