From b67483b3c44eaef2f771fa4c712e13f452675a67 Mon Sep 17 00:00:00 2001 From: Robin Murphy Date: Fri, 19 Apr 2024 17:54:45 +0100 Subject: iommu/dma: Centralise iommu_setup_dma_ops() It's somewhat hard to see, but arm64's arch_setup_dma_ops() should only ever call iommu_setup_dma_ops() after a successful iommu_probe_device(), which means there should be no harm in achieving the same order of operations by running it off the back of iommu_probe_device() itself. This then puts it in line with the x86 and s390 .probe_finalize bodges, letting us pull it all into the main flow properly. As a bonus this lets us fold in and de-scope the PCI workaround setup as well. At this point we can also then pull the call up inside the group mutex, and avoid having to think about whether iommu_group_store_type() could theoretically race and free the domain if iommu_setup_dma_ops() ran just *before* iommu_device_use_default_domain() claims it... Furthermore we replace one .probe_finalize call completely, since the only remaining implementations are now one which only needs to run once for the initial boot-time probe, and two which themselves render that path unreachable. This leaves us a big step closer to realistically being able to unpick the variety of different things that iommu_setup_dma_ops() has been muddling together, and further streamline iommu-dma into core API flows in future. Reviewed-by: Lu Baolu # For Intel IOMMU Reviewed-by: Jason Gunthorpe Tested-by: Hanjun Guo Signed-off-by: Robin Murphy Acked-by: Catalin Marinas Link: https://lore.kernel.org/r/bebea331c1d688b34d9862eefd5ede47503961b8.1713523152.git.robin.murphy@arm.com Signed-off-by: Joerg Roedel --- arch/arm64/mm/dma-mapping.c | 2 -- drivers/iommu/amd/iommu.c | 8 -------- drivers/iommu/dma-iommu.c | 18 ++++++------------ drivers/iommu/dma-iommu.h | 14 ++++++-------- drivers/iommu/intel/iommu.c | 7 ------- drivers/iommu/iommu.c | 20 +++++++------------- drivers/iommu/s390-iommu.c | 6 ------ drivers/iommu/virtio-iommu.c | 10 ---------- include/linux/iommu.h | 7 ------- 9 files changed, 19 insertions(+), 73 deletions(-) diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c index 61886e43e3a1..313d8938a2f0 100644 --- a/arch/arm64/mm/dma-mapping.c +++ b/arch/arm64/mm/dma-mapping.c @@ -58,8 +58,6 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size, ARCH_DMA_MINALIGN, cls); dev->dma_coherent = coherent; - if (device_iommu_mapped(dev)) - iommu_setup_dma_ops(dev, dma_base, dma_base + size - 1); xen_setup_dma_ops(dev); } diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c index d35c1b8c8e65..085abf098fa9 100644 --- a/drivers/iommu/amd/iommu.c +++ b/drivers/iommu/amd/iommu.c @@ -2175,13 +2175,6 @@ static struct iommu_device *amd_iommu_probe_device(struct device *dev) return iommu_dev; } -static void amd_iommu_probe_finalize(struct device *dev) -{ - /* Domains are initialized for this device - have a look what we ended up with */ - set_dma_ops(dev, NULL); - iommu_setup_dma_ops(dev, 0, U64_MAX); -} - static void amd_iommu_release_device(struct device *dev) { struct amd_iommu *iommu; @@ -2784,7 +2777,6 @@ const struct iommu_ops amd_iommu_ops = { .domain_alloc_user = amd_iommu_domain_alloc_user, .probe_device = amd_iommu_probe_device, .release_device = amd_iommu_release_device, - .probe_finalize = amd_iommu_probe_finalize, .device_group = amd_iommu_device_group, .get_resv_regions = amd_iommu_get_resv_regions, .is_attach_deferred = amd_iommu_is_attach_deferred, diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index c827ed690f1f..bc1490bd4f7a 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -1741,25 +1741,20 @@ static const struct dma_map_ops iommu_dma_ops = { .max_mapping_size = iommu_dma_max_mapping_size, }; -/* - * The IOMMU core code allocates the default DMA domain, which the underlying - * IOMMU driver needs to support via the dma-iommu layer. - */ -void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 dma_limit) +void iommu_setup_dma_ops(struct device *dev) { struct iommu_domain *domain = iommu_get_domain_for_dev(dev); - if (!domain) - goto out_err; + if (dev_is_pci(dev)) + dev->iommu->pci_32bit_workaround = !iommu_dma_forcedac; - /* - * The IOMMU core code allocates the default DMA domain, which the - * underlying IOMMU driver needs to support via the dma-iommu layer. - */ if (iommu_is_dma_domain(domain)) { if (iommu_dma_init_domain(domain, dev)) goto out_err; dev->dma_ops = &iommu_dma_ops; + } else if (dev->dma_ops == &iommu_dma_ops) { + /* Clean up if we've switched *from* a DMA domain */ + dev->dma_ops = NULL; } return; @@ -1767,7 +1762,6 @@ out_err: pr_warn("Failed to set up IOMMU for device %s; retaining platform DMA ops\n", dev_name(dev)); } -EXPORT_SYMBOL_GPL(iommu_setup_dma_ops); static struct iommu_dma_msi_page *iommu_dma_get_msi_page(struct device *dev, phys_addr_t msi_addr, struct iommu_domain *domain) diff --git a/drivers/iommu/dma-iommu.h b/drivers/iommu/dma-iommu.h index c829f1f82a99..c12d63457c76 100644 --- a/drivers/iommu/dma-iommu.h +++ b/drivers/iommu/dma-iommu.h @@ -9,6 +9,8 @@ #ifdef CONFIG_IOMMU_DMA +void iommu_setup_dma_ops(struct device *dev); + int iommu_get_dma_cookie(struct iommu_domain *domain); void iommu_put_dma_cookie(struct iommu_domain *domain); @@ -17,13 +19,13 @@ int iommu_dma_init_fq(struct iommu_domain *domain); void iommu_dma_get_resv_regions(struct device *dev, struct list_head *list); extern bool iommu_dma_forcedac; -static inline void iommu_dma_set_pci_32bit_workaround(struct device *dev) -{ - dev->iommu->pci_32bit_workaround = !iommu_dma_forcedac; -} #else /* CONFIG_IOMMU_DMA */ +static inline void iommu_setup_dma_ops(struct device *dev) +{ +} + static inline int iommu_dma_init_fq(struct iommu_domain *domain) { return -EINVAL; @@ -42,9 +44,5 @@ static inline void iommu_dma_get_resv_regions(struct device *dev, struct list_he { } -static inline void iommu_dma_set_pci_32bit_workaround(struct device *dev) -{ -} - #endif /* CONFIG_IOMMU_DMA */ #endif /* __DMA_IOMMU_H */ diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 45c75a8a0ef5..64adfdadeb49 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -4349,12 +4349,6 @@ static void intel_iommu_release_device(struct device *dev) set_dma_ops(dev, NULL); } -static void intel_iommu_probe_finalize(struct device *dev) -{ - set_dma_ops(dev, NULL); - iommu_setup_dma_ops(dev, 0, U64_MAX); -} - static void intel_iommu_get_resv_regions(struct device *device, struct list_head *head) { @@ -4834,7 +4828,6 @@ const struct iommu_ops intel_iommu_ops = { .domain_alloc = intel_iommu_domain_alloc, .domain_alloc_user = intel_iommu_domain_alloc_user, .probe_device = intel_iommu_probe_device, - .probe_finalize = intel_iommu_probe_finalize, .release_device = intel_iommu_release_device, .get_resv_regions = intel_iommu_get_resv_regions, .device_group = intel_iommu_device_group, diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c index 3183b0ed4cdb..9df7cc75c1bc 100644 --- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -581,10 +581,11 @@ static int __iommu_probe_device(struct device *dev, struct list_head *group_list if (list_empty(&group->entry)) list_add_tail(&group->entry, group_list); } - mutex_unlock(&group->mutex); - if (dev_is_pci(dev)) - iommu_dma_set_pci_32bit_workaround(dev); + if (group->default_domain) + iommu_setup_dma_ops(dev); + + mutex_unlock(&group->mutex); return 0; @@ -1828,6 +1829,8 @@ int bus_iommu_probe(const struct bus_type *bus) mutex_unlock(&group->mutex); return ret; } + for_each_group_device(group, gdev) + iommu_setup_dma_ops(gdev->dev); mutex_unlock(&group->mutex); /* @@ -3066,18 +3069,9 @@ static ssize_t iommu_group_store_type(struct iommu_group *group, if (ret) goto out_unlock; - /* - * Release the mutex here because ops->probe_finalize() call-back of - * some vendor IOMMU drivers calls arm_iommu_attach_device() which - * in-turn might call back into IOMMU core code, where it tries to take - * group->mutex, resulting in a deadlock. - */ - mutex_unlock(&group->mutex); - /* Make sure dma_ops is appropriatley set */ for_each_group_device(group, gdev) - iommu_group_do_probe_finalize(gdev->dev); - return count; + iommu_setup_dma_ops(gdev->dev); out_unlock: mutex_unlock(&group->mutex); diff --git a/drivers/iommu/s390-iommu.c b/drivers/iommu/s390-iommu.c index 9a5196f523de..d8eaa7ea380b 100644 --- a/drivers/iommu/s390-iommu.c +++ b/drivers/iommu/s390-iommu.c @@ -695,11 +695,6 @@ static size_t s390_iommu_unmap_pages(struct iommu_domain *domain, return size; } -static void s390_iommu_probe_finalize(struct device *dev) -{ - iommu_setup_dma_ops(dev, 0, U64_MAX); -} - struct zpci_iommu_ctrs *zpci_get_iommu_ctrs(struct zpci_dev *zdev) { if (!zdev || !zdev->s390_domain) @@ -785,7 +780,6 @@ static const struct iommu_ops s390_iommu_ops = { .capable = s390_iommu_capable, .domain_alloc_paging = s390_domain_alloc_paging, .probe_device = s390_iommu_probe_device, - .probe_finalize = s390_iommu_probe_finalize, .release_device = s390_iommu_release_device, .device_group = generic_device_group, .pgsize_bitmap = SZ_4K, diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c index 04048f64a2c0..8e776f6c6e35 100644 --- a/drivers/iommu/virtio-iommu.c +++ b/drivers/iommu/virtio-iommu.c @@ -1025,15 +1025,6 @@ err_free_dev: return ERR_PTR(ret); } -static void viommu_probe_finalize(struct device *dev) -{ -#ifndef CONFIG_ARCH_HAS_SETUP_DMA_OPS - /* First clear the DMA ops in case we're switching from a DMA domain */ - set_dma_ops(dev, NULL); - iommu_setup_dma_ops(dev, 0, U64_MAX); -#endif -} - static void viommu_release_device(struct device *dev) { struct viommu_endpoint *vdev = dev_iommu_priv_get(dev); @@ -1073,7 +1064,6 @@ static struct iommu_ops viommu_ops = { .capable = viommu_capable, .domain_alloc = viommu_domain_alloc, .probe_device = viommu_probe_device, - .probe_finalize = viommu_probe_finalize, .release_device = viommu_release_device, .device_group = viommu_device_group, .get_resv_regions = viommu_get_resv_regions, diff --git a/include/linux/iommu.h b/include/linux/iommu.h index 40dd439307e8..86f0bff3cc95 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -1446,9 +1446,6 @@ static inline void iommu_debugfs_setup(void) {} #ifdef CONFIG_IOMMU_DMA #include -/* Setup call for arch DMA mapping code */ -void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 dma_limit); - int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base); int iommu_dma_prepare_msi(struct msi_desc *desc, phys_addr_t msi_addr); @@ -1459,10 +1456,6 @@ void iommu_dma_compose_msi_msg(struct msi_desc *desc, struct msi_msg *msg); struct msi_desc; struct msi_msg; -static inline void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 dma_limit) -{ -} - static inline int iommu_get_msi_cookie(struct iommu_domain *domain, dma_addr_t base) { return -ENODEV; -- cgit v1.2.3