diff options
| author | David Woodhouse <David.Woodhouse@intel.com> | 2009-07-01 19:30:28 +0100 |
|---|---|---|
| committer | David Woodhouse <David.Woodhouse@intel.com> | 2009-07-01 19:43:37 +0100 |
| commit | 206a73c102fc480ba072a9388bc2142c303113aa (patch) | |
| tree | 0b946089436df51a4444ef23069a9037853d5e61 /drivers/pci | |
| parent | c85994e4771025ef2a66533eb1a4c6c2217b9cda (diff) | |
| download | linux-206a73c102fc480ba072a9388bc2142c303113aa.tar.gz linux-206a73c102fc480ba072a9388bc2142c303113aa.tar.bz2 linux-206a73c102fc480ba072a9388bc2142c303113aa.zip | |
intel-iommu: Kill superfluous mapping_lock
Since we're using cmpxchg64() anyway (because that's the only way to do
an atomic 64-bit store on i386), we might as well ditch the extra
locking and just use cmpxchg64() to ensure that we don't add the page
twice.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/intel-iommu.c | 12 |
1 files changed, 2 insertions, 10 deletions
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c index eea1006c860a..02223e2e27d4 100644 --- a/drivers/pci/intel-iommu.c +++ b/drivers/pci/intel-iommu.c @@ -267,7 +267,6 @@ struct dmar_domain { struct iova_domain iovad; /* iova's that belong to this domain */ struct dma_pte *pgd; /* virtual address */ - spinlock_t mapping_lock; /* page table lock */ int gaw; /* max guest address width */ /* adjusted guest address width, 0 is level 2 30-bit */ @@ -701,13 +700,11 @@ static struct dma_pte *pfn_to_dma_pte(struct dmar_domain *domain, struct dma_pte *parent, *pte = NULL; int level = agaw_to_level(domain->agaw); int offset; - unsigned long flags; BUG_ON(!domain->pgd); BUG_ON(addr_width < BITS_PER_LONG && pfn >> addr_width); parent = domain->pgd; - spin_lock_irqsave(&domain->mapping_lock, flags); while (level > 0) { void *tmp_page; @@ -721,11 +718,9 @@ static struct dma_pte *pfn_to_dma_pte(struct dmar_domain *domain, tmp_page = alloc_pgtable_page(); - if (!tmp_page) { - spin_unlock_irqrestore(&domain->mapping_lock, - flags); + if (!tmp_page) return NULL; - } + domain_flush_cache(domain, tmp_page, VTD_PAGE_SIZE); pteval = (virt_to_dma_pfn(tmp_page) << VTD_PAGE_SHIFT) | DMA_PTE_READ | DMA_PTE_WRITE; if (cmpxchg64(&pte->val, 0ULL, pteval)) { @@ -740,7 +735,6 @@ static struct dma_pte *pfn_to_dma_pte(struct dmar_domain *domain, level--; } - spin_unlock_irqrestore(&domain->mapping_lock, flags); return pte; } @@ -1375,7 +1369,6 @@ static int domain_init(struct dmar_domain *domain, int guest_width) unsigned long sagaw; init_iova_domain(&domain->iovad, DMA_32BIT_PFN); - spin_lock_init(&domain->mapping_lock); spin_lock_init(&domain->iommu_lock); domain_reserve_special_ranges(domain); @@ -3336,7 +3329,6 @@ static int md_domain_init(struct dmar_domain *domain, int guest_width) int adjust_width; init_iova_domain(&domain->iovad, DMA_32BIT_PFN); - spin_lock_init(&domain->mapping_lock); spin_lock_init(&domain->iommu_lock); domain_reserve_special_ranges(domain); |