diff options
Diffstat (limited to 'drivers/iommu/dma-iommu.c')
| -rw-r--r-- | drivers/iommu/dma-iommu.c | 161 |
1 files changed, 145 insertions, 16 deletions
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 00c8a08d56e7..c5ab8667e6f2 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -25,10 +25,29 @@ #include <linux/huge_mm.h> #include <linux/iommu.h> #include <linux/iova.h> +#include <linux/irq.h> #include <linux/mm.h> +#include <linux/pci.h> #include <linux/scatterlist.h> #include <linux/vmalloc.h> +struct iommu_dma_msi_page { + struct list_head list; + dma_addr_t iova; + phys_addr_t phys; +}; + +struct iommu_dma_cookie { + struct iova_domain iovad; + struct list_head msi_page_list; + spinlock_t msi_lock; +}; + +static inline struct iova_domain *cookie_iovad(struct iommu_domain *domain) +{ + return &((struct iommu_dma_cookie *)domain->iova_cookie)->iovad; +} + int iommu_dma_init(void) { return iova_cache_get(); @@ -43,15 +62,19 @@ int iommu_dma_init(void) */ int iommu_get_dma_cookie(struct iommu_domain *domain) { - struct iova_domain *iovad; + struct iommu_dma_cookie *cookie; if (domain->iova_cookie) return -EEXIST; - iovad = kzalloc(sizeof(*iovad), GFP_KERNEL); - domain->iova_cookie = iovad; + cookie = kzalloc(sizeof(*cookie), GFP_KERNEL); + if (!cookie) + return -ENOMEM; - return iovad ? 0 : -ENOMEM; + spin_lock_init(&cookie->msi_lock); + INIT_LIST_HEAD(&cookie->msi_page_list); + domain->iova_cookie = cookie; + return 0; } EXPORT_SYMBOL(iommu_get_dma_cookie); @@ -63,32 +86,58 @@ EXPORT_SYMBOL(iommu_get_dma_cookie); */ void iommu_put_dma_cookie(struct iommu_domain *domain) { - struct iova_domain *iovad = domain->iova_cookie; + struct iommu_dma_cookie *cookie = domain->iova_cookie; + struct iommu_dma_msi_page *msi, *tmp; - if (!iovad) + if (!cookie) return; - if (iovad->granule) - put_iova_domain(iovad); - kfree(iovad); + if (cookie->iovad.granule) + put_iova_domain(&cookie->iovad); + + list_for_each_entry_safe(msi, tmp, &cookie->msi_page_list, list) { + list_del(&msi->list); + kfree(msi); + } + kfree(cookie); domain->iova_cookie = NULL; } EXPORT_SYMBOL(iommu_put_dma_cookie); +static void iova_reserve_pci_windows(struct pci_dev *dev, + struct iova_domain *iovad) +{ + struct pci_host_bridge *bridge = pci_find_host_bridge(dev->bus); + struct resource_entry *window; + unsigned long lo, hi; + + resource_list_for_each_entry(window, &bridge->windows) { + if (resource_type(window->res) != IORESOURCE_MEM && + resource_type(window->res) != IORESOURCE_IO) + continue; + + lo = iova_pfn(iovad, window->res->start - window->offset); + hi = iova_pfn(iovad, window->res->end - window->offset); + reserve_iova(iovad, lo, hi); + } +} + /** * iommu_dma_init_domain - Initialise a DMA mapping domain * @domain: IOMMU domain previously prepared by iommu_get_dma_cookie() * @base: IOVA at which the mappable address space starts * @size: Size of IOVA space + * @dev: Device the domain is being initialised for * * @base and @size should be exact multiples of IOMMU page granularity to * avoid rounding surprises. If necessary, we reserve the page at address 0 * to ensure it is an invalid IOVA. It is safe to reinitialise a domain, but * any change which could make prior IOVAs invalid will fail. */ -int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base, u64 size) +int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base, + u64 size, struct device *dev) { - struct iova_domain *iovad = domain->iova_cookie; + struct iova_domain *iovad = cookie_iovad(domain); unsigned long order, base_pfn, end_pfn; if (!iovad) @@ -124,6 +173,8 @@ int iommu_dma_init_domain(struct iommu_domain *domain, dma_addr_t base, u64 size iovad->dma_32bit_pfn = end_pfn; } else { init_iova_domain(iovad, 1UL << order, base_pfn, end_pfn); + if (dev && dev_is_pci(dev)) + iova_reserve_pci_windows(to_pci_dev(dev), iovad); } return 0; } @@ -155,7 +206,7 @@ int dma_direction_to_prot(enum dma_data_direction dir, bool coherent) static struct iova *__alloc_iova(struct iommu_domain *domain, size_t size, dma_addr_t dma_limit) { - struct iova_domain *iovad = domain->iova_cookie; + struct iova_domain *iovad = cookie_iovad(domain); unsigned long shift = iova_shift(iovad); unsigned long length = iova_align(iovad, size) >> shift; @@ -171,7 +222,7 @@ static struct iova *__alloc_iova(struct iommu_domain *domain, size_t size, /* The IOVA allocator knows what we mapped, so just unmap whatever that was */ static void __iommu_dma_unmap(struct iommu_domain *domain, dma_addr_t dma_addr) { - struct iova_domain *iovad = domain->iova_cookie; + struct iova_domain *iovad = cookie_iovad(domain); unsigned long shift = iova_shift(iovad); unsigned long pfn = dma_addr >> shift; struct iova *iova = find_iova(iovad, pfn); @@ -294,7 +345,7 @@ struct page **iommu_dma_alloc(struct device *dev, size_t size, gfp_t gfp, void (*flush_page)(struct device *, const void *, phys_addr_t)) { struct iommu_domain *domain = iommu_get_domain_for_dev(dev); - struct iova_domain *iovad = domain->iova_cookie; + struct iova_domain *iovad = cookie_iovad(domain); struct iova *iova; struct page **pages; struct sg_table sgt; @@ -386,7 +437,7 @@ dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page, { dma_addr_t dma_addr; struct iommu_domain *domain = iommu_get_domain_for_dev(dev); - struct iova_domain *iovad = domain->iova_cookie; + struct iova_domain *iovad = cookie_iovad(domain); phys_addr_t phys = page_to_phys(page) + offset; size_t iova_off = iova_offset(iovad, phys); size_t len = iova_align(iovad, size + iova_off); @@ -495,7 +546,7 @@ int iommu_dma_map_sg(struct device *dev, struct scatterlist *sg, int nents, int prot) { struct iommu_domain *domain = iommu_get_domain_for_dev(dev); - struct iova_domain *iovad = domain->iova_cookie; + struct iova_domain *iovad = cookie_iovad(domain); struct iova *iova; struct scatterlist *s, *prev = NULL; dma_addr_t dma_addr; @@ -587,3 +638,81 @@ int iommu_dma_mapping_error(struct device *dev, dma_addr_t dma_addr) { return dma_addr == DMA_ERROR_CODE; } + +static struct iommu_dma_msi_page *iommu_dma_get_msi_page(struct device *dev, + phys_addr_t msi_addr, struct iommu_domain *domain) +{ + struct iommu_dma_cookie *cookie = domain->iova_cookie; + struct iommu_dma_msi_page *msi_page; + struct iova_domain *iovad = &cookie->iovad; + struct iova *iova; + int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO; + + msi_addr &= ~(phys_addr_t)iova_mask(iovad); + list_for_each_entry(msi_page, &cookie->msi_page_list, list) + if (msi_page->phys == msi_addr) + return msi_page; + + msi_page = kzalloc(sizeof(*msi_page), GFP_ATOMIC); + if (!msi_page) + return NULL; + + iova = __alloc_iova(domain, iovad->granule, dma_get_mask(dev)); + if (!iova) + goto out_free_page; + + msi_page->phys = msi_addr; + msi_page->iova = iova_dma_addr(iovad, iova); + if (iommu_map(domain, msi_page->iova, msi_addr, iovad->granule, prot)) + goto out_free_iova; + + INIT_LIST_HEAD(&msi_page->list); + list_add(&msi_page->list, &cookie->msi_page_list); + return msi_page; + +out_free_iova: + __free_iova(iovad, iova); +out_free_page: + kfree(msi_page); + return NULL; +} + +void iommu_dma_map_msi_msg(int irq, struct msi_msg *msg) +{ + struct device *dev = msi_desc_to_dev(irq_get_msi_desc(irq)); + struct iommu_domain *domain = iommu_get_domain_for_dev(dev); + struct iommu_dma_cookie *cookie; + struct iommu_dma_msi_page *msi_page; + phys_addr_t msi_addr = (u64)msg->address_hi << 32 | msg->address_lo; + unsigned long flags; + + if (!domain || !domain->iova_cookie) + return; + + cookie = domain->iova_cookie; + + /* + * We disable IRQs to rule out a possible inversion against + * irq_desc_lock if, say, someone tries to retarget the affinity + * of an MSI from within an IPI handler. + */ + spin_lock_irqsave(&cookie->msi_lock, flags); + msi_page = iommu_dma_get_msi_page(dev, msi_addr, domain); + spin_unlock_irqrestore(&cookie->msi_lock, flags); + + if (WARN_ON(!msi_page)) { + /* + * We're called from a void callback, so the best we can do is + * 'fail' by filling the message with obviously bogus values. + * Since we got this far due to an IOMMU being present, it's + * not like the existing address would have worked anyway... + */ + msg->address_hi = ~0U; + msg->address_lo = ~0U; + msg->data = ~0U; + } else { + msg->address_hi = upper_32_bits(msi_page->iova); + msg->address_lo &= iova_mask(&cookie->iovad); + msg->address_lo += lower_32_bits(msi_page->iova); + } +} |