diff options
author | Jason Gunthorpe <jgg@nvidia.com> | 2023-09-13 16:43:42 +0300 |
---|---|---|
committer | Joerg Roedel <jroedel@suse.de> | 2023-09-25 12:40:57 +0300 |
commit | e98befd010bd56b8b3f2afea2d600e30df023e6b (patch) | |
tree | af3f5f4e4cf61510a86335312dfc300212c442ac | |
parent | 59ddce4418da483c932bc7a08b88d6ba14020e83 (diff) | |
download | linux-e98befd010bd56b8b3f2afea2d600e30df023e6b.tar.xz |
iommu: Allow an IDENTITY domain as the default_domain in ARM32
Even though dma-iommu.c and CONFIG_ARM_DMA_USE_IOMMU do approximately the
same stuff, the way they relate to the IOMMU core is quiet different.
dma-iommu.c expects the core code to setup an UNMANAGED domain (of type
IOMMU_DOMAIN_DMA) and then configures itself to use that domain. This
becomes the default_domain for the group.
ARM_DMA_USE_IOMMU does not use the default_domain, instead it directly
allocates an UNMANAGED domain and operates it just like an external
driver. In this case group->default_domain is NULL.
If the driver provides a global static identity_domain then automatically
use it as the default_domain when in ARM_DMA_USE_IOMMU mode.
This allows drivers that implemented default_domain == NULL as an IDENTITY
translation to trivially get a properly labeled non-NULL default_domain on
ARM32 configs.
With this arrangment when ARM_DMA_USE_IOMMU wants to disconnect from the
device the normal detach_domain flow will restore the IDENTITY domain as
the default domain. Overall this makes attach_dev() of the IDENTITY domain
called in the same places as detach_dev().
This effectively migrates these drivers to default_domain mode. For
drivers that support ARM64 they will gain support for the IDENTITY
translation mode for the dma_api and behave in a uniform way.
Drivers use this by setting ops->identity_domain to a static singleton
iommu_domain that implements the identity attach. If the core detects
ARM_DMA_USE_IOMMU mode then it automatically attaches the IDENTITY domain
during probe.
Drivers can continue to prevent the use of DMA translation by returning
IOMMU_DOMAIN_IDENTITY from def_domain_type, this will completely prevent
IOMMU_DMA from running but will not impact ARM_DMA_USE_IOMMU.
This allows removing the set_platform_dma_ops() from every remaining
driver.
Remove the set_platform_dma_ops from rockchip and mkt_v1 as all it does
is set an existing global static identity domain. mkt_v1 does not support
IOMMU_DOMAIN_DMA and it does not compile on ARM64 so this transformation
is safe.
Tested-by: Steven Price <steven.price@arm.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/9-v8-81230027b2fa+9d-iommu_all_defdom_jgg@nvidia.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
-rw-r--r-- | drivers/iommu/iommu.c | 21 | ||||
-rw-r--r-- | drivers/iommu/mtk_iommu_v1.c | 12 | ||||
-rw-r--r-- | drivers/iommu/rockchip-iommu.c | 10 |
3 files changed, 20 insertions, 23 deletions
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 9188eae61e92..1efd6351bbc2 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -1865,17 +1865,36 @@ static int iommu_get_def_domain_type(struct iommu_group *group, static int iommu_get_default_domain_type(struct iommu_group *group, int target_type) { + const struct iommu_ops *ops = group_iommu_ops(group); struct device *untrusted = NULL; struct group_device *gdev; int driver_type = 0; lockdep_assert_held(&group->mutex); + + /* + * ARM32 drivers supporting CONFIG_ARM_DMA_USE_IOMMU can declare an + * identity_domain and it will automatically become their default + * domain. Later on ARM_DMA_USE_IOMMU will install its UNMANAGED domain. + * Override the selection to IDENTITY if we are sure the driver supports + * it. + */ + if (IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU) && ops->identity_domain) + driver_type = IOMMU_DOMAIN_IDENTITY; + for_each_group_device(group, gdev) { driver_type = iommu_get_def_domain_type(group, gdev->dev, driver_type); - if (dev_is_pci(gdev->dev) && to_pci_dev(gdev->dev)->untrusted) + if (dev_is_pci(gdev->dev) && to_pci_dev(gdev->dev)->untrusted) { + /* + * No ARM32 using systems will set untrusted, it cannot + * work. + */ + if (WARN_ON(IS_ENABLED(CONFIG_ARM_DMA_USE_IOMMU))) + return -1; untrusted = gdev->dev; + } } if (untrusted) { diff --git a/drivers/iommu/mtk_iommu_v1.c b/drivers/iommu/mtk_iommu_v1.c index cc3e7d53d33a..7c0c1d50df5f 100644 --- a/drivers/iommu/mtk_iommu_v1.c +++ b/drivers/iommu/mtk_iommu_v1.c @@ -337,11 +337,6 @@ static struct iommu_domain mtk_iommu_v1_identity_domain = { .ops = &mtk_iommu_v1_identity_ops, }; -static void mtk_iommu_v1_set_platform_dma(struct device *dev) -{ - mtk_iommu_v1_identity_attach(&mtk_iommu_v1_identity_domain, dev); -} - static int mtk_iommu_v1_map(struct iommu_domain *domain, unsigned long iova, phys_addr_t paddr, size_t pgsize, size_t pgcount, int prot, gfp_t gfp, size_t *mapped) @@ -457,11 +452,6 @@ static int mtk_iommu_v1_create_mapping(struct device *dev, struct of_phandle_arg return 0; } -static int mtk_iommu_v1_def_domain_type(struct device *dev) -{ - return IOMMU_DOMAIN_IDENTITY; -} - static struct iommu_device *mtk_iommu_v1_probe_device(struct device *dev) { struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); @@ -599,10 +589,8 @@ static const struct iommu_ops mtk_iommu_v1_ops = { .probe_device = mtk_iommu_v1_probe_device, .probe_finalize = mtk_iommu_v1_probe_finalize, .release_device = mtk_iommu_v1_release_device, - .def_domain_type = mtk_iommu_v1_def_domain_type, .device_group = generic_device_group, .pgsize_bitmap = MT2701_IOMMU_PAGE_SIZE, - .set_platform_dma_ops = mtk_iommu_v1_set_platform_dma, .owner = THIS_MODULE, .default_domain_ops = &(const struct iommu_domain_ops) { .attach_dev = mtk_iommu_v1_attach_device, diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c index 033678f2f8b3..a582525d36f8 100644 --- a/drivers/iommu/rockchip-iommu.c +++ b/drivers/iommu/rockchip-iommu.c @@ -998,13 +998,6 @@ static struct iommu_domain rk_identity_domain = { .ops = &rk_identity_ops, }; -#ifdef CONFIG_ARM -static void rk_iommu_set_platform_dma(struct device *dev) -{ - WARN_ON(rk_iommu_identity_attach(&rk_identity_domain, dev)); -} -#endif - static int rk_iommu_attach_device(struct iommu_domain *domain, struct device *dev) { @@ -1183,9 +1176,6 @@ static const struct iommu_ops rk_iommu_ops = { .probe_device = rk_iommu_probe_device, .release_device = rk_iommu_release_device, .device_group = rk_iommu_device_group, -#ifdef CONFIG_ARM - .set_platform_dma_ops = rk_iommu_set_platform_dma, -#endif .pgsize_bitmap = RK_IOMMU_PGSIZE_BITMAP, .of_xlate = rk_iommu_of_xlate, .default_domain_ops = &(const struct iommu_domain_ops) { |