From 1b72250076dde4276acecf3a7da722b185703e78 Mon Sep 17 00:00:00 2001 From: Robin Murphy Date: Mon, 12 Jan 2015 17:51:15 +0000 Subject: [PATCH] iommu: Make IOVA domain low limit flexible To share the IOVA allocator with other architectures, it needs to accommodate more general aperture restrictions; move the lower limit from a compile-time constant to a runtime domain property to allow IOVA domains with different requirements to co-exist. Also reword the slightly unclear description of alloc_iova since we're touching it anyway. Signed-off-by: Robin Murphy Signed-off-by: Joerg Roedel --- drivers/iommu/intel-iommu.c | 9 ++++++--- drivers/iommu/iova.c | 10 ++++++---- include/linux/iova.h | 7 +++---- 3 files changed, 15 insertions(+), 11 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index e758d8ed8fb5..86f9e82b015b 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -71,6 +71,9 @@ __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) #define DMA_32BIT_PFN IOVA_PFN(DMA_BIT_MASK(32)) #define DMA_64BIT_PFN IOVA_PFN(DMA_BIT_MASK(64)) @@ -1632,7 +1635,7 @@ static int dmar_init_reserved_ranges(void) struct iova *iova; int i; - init_iova_domain(&reserved_iova_list, DMA_32BIT_PFN); + init_iova_domain(&reserved_iova_list, IOVA_START_PFN, DMA_32BIT_PFN); lockdep_set_class(&reserved_iova_list.iova_rbtree_lock, &reserved_rbtree_key); @@ -1690,7 +1693,7 @@ static int domain_init(struct dmar_domain *domain, int guest_width) int adjust_width, agaw; unsigned long sagaw; - init_iova_domain(&domain->iovad, DMA_32BIT_PFN); + init_iova_domain(&domain->iovad, IOVA_START_PFN, DMA_32BIT_PFN); domain_reserve_special_ranges(domain); /* calculate AGAW */ @@ -4313,7 +4316,7 @@ static int md_domain_init(struct dmar_domain *domain, int guest_width) { int adjust_width; - init_iova_domain(&domain->iovad, DMA_32BIT_PFN); + init_iova_domain(&domain->iovad, IOVA_START_PFN, DMA_32BIT_PFN); domain_reserve_special_ranges(domain); /* calculate AGAW */ diff --git a/drivers/iommu/iova.c b/drivers/iommu/iova.c index 520b8c8ae0c4..a3dbba8caa19 100644 --- a/drivers/iommu/iova.c +++ b/drivers/iommu/iova.c @@ -55,11 +55,13 @@ void free_iova_mem(struct iova *iova) } void -init_iova_domain(struct iova_domain *iovad, unsigned long pfn_32bit) +init_iova_domain(struct iova_domain *iovad, unsigned long start_pfn, + unsigned long pfn_32bit) { spin_lock_init(&iovad->iova_rbtree_lock); iovad->rbroot = RB_ROOT; iovad->cached32_node = NULL; + iovad->start_pfn = start_pfn; iovad->dma_32bit_pfn = pfn_32bit; } @@ -162,7 +164,7 @@ move_left: if (!curr) { if (size_aligned) pad_size = iova_get_pad_size(size, limit_pfn); - if ((IOVA_START_PFN + size + pad_size) > limit_pfn) { + if ((iovad->start_pfn + size + pad_size) > limit_pfn) { spin_unlock_irqrestore(&iovad->iova_rbtree_lock, flags); return -ENOMEM; } @@ -237,8 +239,8 @@ iova_insert_rbtree(struct rb_root *root, struct iova *iova) * @size: - size of page frames to allocate * @limit_pfn: - max limit address * @size_aligned: - set if size_aligned address range is required - * This function allocates an iova in the range limit_pfn to IOVA_START_PFN - * looking from limit_pfn instead from IOVA_START_PFN. If the size_aligned + * This function allocates an iova in the range iovad->start_pfn to limit_pfn, + * searching top-down from limit_pfn to iovad->start_pfn. If the size_aligned * flag is set then the allocated address iova->pfn_lo will be naturally * aligned on roundup_power_of_two(size). */ diff --git a/include/linux/iova.h b/include/linux/iova.h index ad0507c61cc7..591b19626b46 100644 --- a/include/linux/iova.h +++ b/include/linux/iova.h @@ -16,9 +16,6 @@ #include #include -/* IO virtual address start page frame number */ -#define IOVA_START_PFN (1) - /* iova structure */ struct iova { struct rb_node node; @@ -31,6 +28,7 @@ struct iova_domain { spinlock_t iova_rbtree_lock; /* Lock to protect update of rbtree */ struct rb_root rbroot; /* iova domain rbtree root */ struct rb_node *cached32_node; /* Save last alloced node */ + unsigned long start_pfn; /* Lower limit for this domain */ unsigned long dma_32bit_pfn; }; @@ -52,7 +50,8 @@ struct iova *alloc_iova(struct iova_domain *iovad, unsigned long size, struct iova *reserve_iova(struct iova_domain *iovad, unsigned long pfn_lo, unsigned long pfn_hi); void copy_reserved_iova(struct iova_domain *from, struct iova_domain *to); -void init_iova_domain(struct iova_domain *iovad, unsigned long pfn_32bit); +void init_iova_domain(struct iova_domain *iovad, unsigned long start_pfn, + unsigned long pfn_32bit); struct iova *find_iova(struct iova_domain *iovad, unsigned long pfn); void put_iova_domain(struct iova_domain *iovad); struct iova *split_and_remove_iova(struct iova_domain *iovad, -- 2.34.1