From a2b312c445ac6f683167d903d93b374441f1018a Mon Sep 17 00:00:00 2001 From: James Sewart Date: Mon, 11 Mar 2019 14:53:47 +0000 Subject: [PATCH 8/9] iommu/vt-d: Allow IOMMU_DOMAIN_DMA to be allocated by iommu_ops Allowing IOMMU_DOMAIN_DMA type IOMMU domain to be allocated allows the default_domain of an iommu_group to be set. This delegates device-domain relationships to the generic IOMMU code. Signed-off-by: James Sewart diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 3a06e8804b6e..2055c11f5978 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -311,6 +311,18 @@ static int hw_pass_through = 1; /* si_domain contains mulitple devices */ #define DOMAIN_FLAG_STATIC_IDENTITY (1 << 1) +/* + * Domain managed externally, don't cleanup if it isn't attached + * to any devices. + */ +#define DOMAIN_FLAG_MANAGED_EXTERNALLY (1 << 2) + +/* + * Set after domain initialisation. Used when allocating dma domains to + * defer domain initialisation until it is attached to a device + */ +#define DOMAIN_FLAG_INITIALISED (1 << 3) + #define for_each_domain_iommu(idx, domain) \ for (idx = 0; idx < g_num_of_iommus; idx++) \ if (domain->iommu_refcnt[idx]) @@ -561,6 +573,16 @@ static inline int domain_type_is_vm_or_si(struct dmar_domain *domain) DOMAIN_FLAG_STATIC_IDENTITY); } +static inline int domain_managed_externally(struct dmar_domain *domain) +{ + return domain->flags & DOMAIN_FLAG_MANAGED_EXTERNALLY; +} + +static inline int domain_is_initialised(struct dmar_domain *domain) +{ + return domain->flags & DOMAIN_FLAG_INITIALISED; +} + static inline int domain_pfn_supported(struct dmar_domain *domain, unsigned long pfn) { @@ -1671,7 +1693,7 @@ static void disable_dmar_iommu(struct intel_iommu *iommu) __dmar_remove_one_dev_info(info); - if (!domain_type_is_vm_or_si(domain)) { + if (!domain_managed_externally(domain)) { /* * The domain_exit() function can't be called under * device_domain_lock, as it takes this lock itself. @@ -1904,6 +1926,7 @@ static int domain_init(struct dmar_domain *domain, struct intel_iommu *iommu, domain->pgd = (struct dma_pte *)alloc_pgtable_page(domain->nid); if (!domain->pgd) return -ENOMEM; + domain->flags |= DOMAIN_FLAG_INITIALISED; __iommu_flush_cache(iommu, domain->pgd, PAGE_SIZE); return 0; } @@ -1912,6 +1935,9 @@ static void domain_exit(struct dmar_domain *domain) { struct page *freelist; + if (!domain_is_initialised(domain)) + goto free_mem; + /* Remove associated devices and clear attached or cached domains */ rcu_read_lock(); domain_remove_dev_info(domain); @@ -1924,6 +1950,7 @@ static void domain_exit(struct dmar_domain *domain) dma_free_pagelist(freelist); +free_mem: free_domain_mem(domain); } @@ -4589,7 +4616,7 @@ static int device_notifier(struct notifier_block *nb, return 0; dmar_remove_one_dev_info(dev); - if (!domain_type_is_vm_or_si(domain) && + if (!domain_managed_externally(domain) && list_empty(&domain->devices)) domain_exit(domain); } else if (action == BUS_NOTIFY_ADD_DEVICE) { @@ -5047,6 +5074,7 @@ static int md_domain_init(struct dmar_domain *domain, int guest_width) domain->pgd = (struct dma_pte *)alloc_pgtable_page(domain->nid); if (!domain->pgd) return -ENOMEM; + domain->flags |= DOMAIN_FLAG_INITIALISED; domain_flush_cache(domain, domain->pgd, PAGE_SIZE); return 0; } @@ -5055,28 +5083,43 @@ static struct iommu_domain *intel_iommu_domain_alloc(unsigned type) { struct dmar_domain *dmar_domain; struct iommu_domain *domain; + int flags = DOMAIN_FLAG_MANAGED_EXTERNALLY; - if (type != IOMMU_DOMAIN_UNMANAGED) - return NULL; + switch (type) { + case IOMMU_DOMAIN_UNMANAGED: + flags |= DOMAIN_FLAG_VIRTUAL_MACHINE | DOMAIN_FLAG_INITIALISED; + dmar_domain = alloc_domain(flags); + if (!dmar_domain) + return NULL; - dmar_domain = alloc_domain(DOMAIN_FLAG_VIRTUAL_MACHINE); - if (!dmar_domain) { - pr_err("Can't allocate dmar_domain\n"); - return NULL; - } - if (md_domain_init(dmar_domain, DEFAULT_DOMAIN_ADDRESS_WIDTH)) { - pr_err("Domain initialization failed\n"); - domain_exit(dmar_domain); + if (md_domain_init(dmar_domain, DEFAULT_DOMAIN_ADDRESS_WIDTH)) { + pr_err("Domain initialization failed\n"); + domain_exit(dmar_domain); + return NULL; + } + domain_update_iommu_cap(dmar_domain); + domain = &dmar_domain->domain; + domain->geometry.aperture_start = 0; + domain->geometry.aperture_end = + __DOMAIN_MAX_ADDR(dmar_domain->gaw); + domain->geometry.force_aperture = true; + break; + case IOMMU_DOMAIN_DMA: + dmar_domain = alloc_domain(flags); + if (!dmar_domain) + return NULL; + /* + * init domain in device attach when we know IOMMU + * capabilities + */ + break; + case IOMMU_DOMAIN_IDENTITY: + return &si_domain->domain; + default: return NULL; } - domain_update_iommu_cap(dmar_domain); - - domain = &dmar_domain->domain; - domain->geometry.aperture_start = 0; - domain->geometry.aperture_end = __DOMAIN_MAX_ADDR(dmar_domain->gaw); - domain->geometry.force_aperture = true; - return domain; + return &dmar_domain->domain; } static void intel_iommu_domain_free(struct iommu_domain *domain) @@ -5107,7 +5150,7 @@ static int intel_iommu_attach_device(struct iommu_domain *domain, dmar_remove_one_dev_info(dev); rcu_read_unlock(); - if (!domain_type_is_vm_or_si(old_domain) && + if (!domain_managed_externally(old_domain) && list_empty(&old_domain->devices)) domain_exit(old_domain); } @@ -5117,6 +5160,16 @@ static int intel_iommu_attach_device(struct iommu_domain *domain, if (!iommu) return -ENODEV; + /* + * Initialise domain with IOMMU capabilities if it isn't already + * initialised + */ + if (!domain_is_initialised(dmar_domain)) { + if (domain_init(dmar_domain, iommu, + DEFAULT_DOMAIN_ADDRESS_WIDTH)) + return -ENOMEM; + } + /* check if this iommu agaw is sufficient for max mapped address */ addr_width = agaw_to_width(iommu->agaw); if (addr_width > cap_mgaw(iommu->cap)) @@ -5163,6 +5216,10 @@ static int intel_iommu_map(struct iommu_domain *domain, int prot = 0; int ret; + /* Don't bother if hardware passthrough used. */ + if (dmar_domain == si_domain && hw_pass_through) + return 0; + if (iommu_prot & IOMMU_READ) prot |= DMA_PTE_READ; if (iommu_prot & IOMMU_WRITE) -- 2.17.1