From c4d27ffaa8eb034ec438a9aedfe202ce81e15312 Mon Sep 17 00:00:00 2001 From: Lu Baolu Date: Wed, 24 Apr 2024 15:16:34 +0800 Subject: iommu/vt-d: Add cache tag invalidation helpers Add several helpers to invalidate the caches after mappings in the affected domain are changed. - cache_tag_flush_range() invalidates a range of caches after mappings within this range are changed. It uses the page-selective cache invalidation methods. - cache_tag_flush_all() invalidates all caches tagged by a domain ID. It uses the domain-selective cache invalidation methods. - cache_tag_flush_range_np() invalidates a range of caches when new mappings are created in the domain and the corresponding page table entries change from non-present to present. Signed-off-by: Lu Baolu Reviewed-by: Kevin Tian Link: https://lore.kernel.org/r/20240416080656.60968-3-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel --- drivers/iommu/intel/cache.c | 195 ++++++++++++++++++++++++++++++++++++++++++++ drivers/iommu/intel/iommu.c | 12 --- drivers/iommu/intel/iommu.h | 14 ++++ 3 files changed, 209 insertions(+), 12 deletions(-) (limited to 'drivers/iommu/intel') diff --git a/drivers/iommu/intel/cache.c b/drivers/iommu/intel/cache.c index 296f1645a739..0539275a9d20 100644 --- a/drivers/iommu/intel/cache.c +++ b/drivers/iommu/intel/cache.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include "iommu.h" @@ -212,3 +213,197 @@ void cache_tag_unassign_domain(struct dmar_domain *domain, if (domain->domain.type == IOMMU_DOMAIN_NESTED) __cache_tag_unassign_parent_domain(domain->s2_domain, did, dev, pasid); } + +static unsigned long calculate_psi_aligned_address(unsigned long start, + unsigned long end, + unsigned long *_pages, + unsigned long *_mask) +{ + unsigned long pages = aligned_nrpages(start, end - start + 1); + unsigned long aligned_pages = __roundup_pow_of_two(pages); + unsigned long bitmask = aligned_pages - 1; + unsigned long mask = ilog2(aligned_pages); + unsigned long pfn = IOVA_PFN(start); + + /* + * PSI masks the low order bits of the base address. If the + * address isn't aligned to the mask, then compute a mask value + * needed to ensure the target range is flushed. + */ + if (unlikely(bitmask & pfn)) { + unsigned long end_pfn = pfn + pages - 1, shared_bits; + + /* + * Since end_pfn <= pfn + bitmask, the only way bits + * higher than bitmask can differ in pfn and end_pfn is + * by carrying. This means after masking out bitmask, + * high bits starting with the first set bit in + * shared_bits are all equal in both pfn and end_pfn. + */ + shared_bits = ~(pfn ^ end_pfn) & ~bitmask; + mask = shared_bits ? __ffs(shared_bits) : BITS_PER_LONG; + } + + *_pages = aligned_pages; + *_mask = mask; + + return ALIGN_DOWN(start, VTD_PAGE_SIZE << mask); +} + +/* + * Invalidates a range of IOVA from @start (inclusive) to @end (inclusive) + * when the memory mappings in the target domain have been modified. + */ +void cache_tag_flush_range(struct dmar_domain *domain, unsigned long start, + unsigned long end, int ih) +{ + unsigned long pages, mask, addr; + struct cache_tag *tag; + unsigned long flags; + + addr = calculate_psi_aligned_address(start, end, &pages, &mask); + + spin_lock_irqsave(&domain->cache_lock, flags); + list_for_each_entry(tag, &domain->cache_tags, node) { + struct intel_iommu *iommu = tag->iommu; + struct device_domain_info *info; + u16 sid; + + switch (tag->type) { + case CACHE_TAG_IOTLB: + case CACHE_TAG_NESTING_IOTLB: + if (domain->use_first_level) { + qi_flush_piotlb(iommu, tag->domain_id, + tag->pasid, addr, pages, ih); + } else { + /* + * Fallback to domain selective flush if no + * PSI support or the size is too big. + */ + if (!cap_pgsel_inv(iommu->cap) || + mask > cap_max_amask_val(iommu->cap)) + iommu->flush.flush_iotlb(iommu, tag->domain_id, + 0, 0, DMA_TLB_DSI_FLUSH); + else + iommu->flush.flush_iotlb(iommu, tag->domain_id, + addr | ih, mask, + DMA_TLB_PSI_FLUSH); + } + break; + case CACHE_TAG_NESTING_DEVTLB: + /* + * Address translation cache in device side caches the + * result of nested translation. There is no easy way + * to identify the exact set of nested translations + * affected by a change in S2. So just flush the entire + * device cache. + */ + addr = 0; + mask = MAX_AGAW_PFN_WIDTH; + fallthrough; + case CACHE_TAG_DEVTLB: + info = dev_iommu_priv_get(tag->dev); + sid = PCI_DEVID(info->bus, info->devfn); + + if (tag->pasid == IOMMU_NO_PASID) + qi_flush_dev_iotlb(iommu, sid, info->pfsid, + info->ats_qdep, addr, mask); + else + qi_flush_dev_iotlb_pasid(iommu, sid, info->pfsid, + tag->pasid, info->ats_qdep, + addr, mask); + + quirk_extra_dev_tlb_flush(info, addr, mask, tag->pasid, info->ats_qdep); + break; + } + } + spin_unlock_irqrestore(&domain->cache_lock, flags); +} + +/* + * Invalidates all ranges of IOVA when the memory mappings in the target + * domain have been modified. + */ +void cache_tag_flush_all(struct dmar_domain *domain) +{ + struct cache_tag *tag; + unsigned long flags; + + spin_lock_irqsave(&domain->cache_lock, flags); + list_for_each_entry(tag, &domain->cache_tags, node) { + struct intel_iommu *iommu = tag->iommu; + struct device_domain_info *info; + u16 sid; + + switch (tag->type) { + case CACHE_TAG_IOTLB: + case CACHE_TAG_NESTING_IOTLB: + if (domain->use_first_level) + qi_flush_piotlb(iommu, tag->domain_id, + tag->pasid, 0, -1, 0); + else + iommu->flush.flush_iotlb(iommu, tag->domain_id, + 0, 0, DMA_TLB_DSI_FLUSH); + break; + case CACHE_TAG_DEVTLB: + case CACHE_TAG_NESTING_DEVTLB: + info = dev_iommu_priv_get(tag->dev); + sid = PCI_DEVID(info->bus, info->devfn); + + qi_flush_dev_iotlb(iommu, sid, info->pfsid, info->ats_qdep, + 0, MAX_AGAW_PFN_WIDTH); + quirk_extra_dev_tlb_flush(info, 0, MAX_AGAW_PFN_WIDTH, + IOMMU_NO_PASID, info->ats_qdep); + break; + } + } + spin_unlock_irqrestore(&domain->cache_lock, flags); +} + +/* + * Invalidate a range of IOVA when new mappings are created in the target + * domain. + * + * - VT-d spec, Section 6.1 Caching Mode: When the CM field is reported as + * Set, any software updates to remapping structures other than first- + * stage mapping requires explicit invalidation of the caches. + * - VT-d spec, Section 6.8 Write Buffer Flushing: For hardware that requires + * write buffer flushing, software must explicitly perform write-buffer + * flushing, if cache invalidation is not required. + */ +void cache_tag_flush_range_np(struct dmar_domain *domain, unsigned long start, + unsigned long end) +{ + unsigned long pages, mask, addr; + struct cache_tag *tag; + unsigned long flags; + + addr = calculate_psi_aligned_address(start, end, &pages, &mask); + + spin_lock_irqsave(&domain->cache_lock, flags); + list_for_each_entry(tag, &domain->cache_tags, node) { + struct intel_iommu *iommu = tag->iommu; + + if (!cap_caching_mode(iommu->cap) || domain->use_first_level) { + iommu_flush_write_buffer(iommu); + continue; + } + + if (tag->type == CACHE_TAG_IOTLB || + tag->type == CACHE_TAG_NESTING_IOTLB) { + /* + * Fallback to domain selective flush if no + * PSI support or the size is too big. + */ + if (!cap_pgsel_inv(iommu->cap) || + mask > cap_max_amask_val(iommu->cap)) + iommu->flush.flush_iotlb(iommu, tag->domain_id, + 0, 0, DMA_TLB_DSI_FLUSH); + else + iommu->flush.flush_iotlb(iommu, tag->domain_id, + addr, mask, + DMA_TLB_PSI_FLUSH); + } + } + spin_unlock_irqrestore(&domain->cache_lock, flags); +} diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 8220bb36e420..473df7cd1672 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -54,11 +54,6 @@ __DOMAIN_MAX_PFN(gaw), (unsigned long)-1)) #define DOMAIN_MAX_ADDR(gaw) (((uint64_t)__DOMAIN_MAX_PFN(gaw)) << VTD_PAGE_SHIFT) -/* IO virtual address start page frame number */ -#define IOVA_START_PFN (1) - -#define IOVA_PFN(addr) ((addr) >> PAGE_SHIFT) - static void __init check_tylersburg_isoch(void); static int rwbf_quirk; @@ -1992,13 +1987,6 @@ domain_context_mapping(struct dmar_domain *domain, struct device *dev) domain_context_mapping_cb, domain); } -/* Returns a number of VTD pages, but aligned to MM page size */ -static unsigned long aligned_nrpages(unsigned long host_addr, size_t size) -{ - host_addr &= ~PAGE_MASK; - return PAGE_ALIGN(host_addr + size) >> VTD_PAGE_SHIFT; -} - /* Return largest possible superpage level for a given mapping */ static int hardware_largepage_caps(struct dmar_domain *domain, unsigned long iov_pfn, unsigned long phy_pfn, unsigned long pages) diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h index b7c79cc19681..cb83b0995391 100644 --- a/drivers/iommu/intel/iommu.h +++ b/drivers/iommu/intel/iommu.h @@ -35,6 +35,8 @@ #define VTD_PAGE_MASK (((u64)-1) << VTD_PAGE_SHIFT) #define VTD_PAGE_ALIGN(addr) (((addr) + VTD_PAGE_SIZE - 1) & VTD_PAGE_MASK) +#define IOVA_PFN(addr) ((addr) >> PAGE_SHIFT) + #define VTD_STRIDE_SHIFT (9) #define VTD_STRIDE_MASK (((u64)-1) << VTD_STRIDE_SHIFT) @@ -1040,6 +1042,13 @@ static inline void context_set_sm_pre(struct context_entry *context) context->lo |= BIT_ULL(4); } +/* Returns a number of VTD pages, but aligned to MM page size */ +static inline unsigned long aligned_nrpages(unsigned long host_addr, size_t size) +{ + host_addr &= ~PAGE_MASK; + return PAGE_ALIGN(host_addr + size) >> VTD_PAGE_SHIFT; +} + /* Convert value to context PASID directory size field coding. */ #define context_pdts(pds) (((pds) & 0x7) << 9) @@ -1121,6 +1130,11 @@ int cache_tag_assign_domain(struct dmar_domain *domain, struct device *dev, ioasid_t pasid); void cache_tag_unassign_domain(struct dmar_domain *domain, struct device *dev, ioasid_t pasid); +void cache_tag_flush_range(struct dmar_domain *domain, unsigned long start, + unsigned long end, int ih); +void cache_tag_flush_all(struct dmar_domain *domain); +void cache_tag_flush_range_np(struct dmar_domain *domain, unsigned long start, + unsigned long end); #ifdef CONFIG_INTEL_IOMMU_SVM void intel_svm_check(struct intel_iommu *iommu); -- cgit v1.2.3