From c0e8a6c8033e205835fa5e67db7ab4589d2491b2 Mon Sep 17 00:00:00 2001 From: Joerg Roedel Date: Tue, 21 Jul 2015 09:39:46 +0200 Subject: [PATCH] iommu/vt-d: Keep track of per-iommu domain ids Instead of searching in the domain array for already allocated domain ids, keep track of them explicitly. Signed-off-by: Joerg Roedel --- drivers/iommu/intel-iommu.c | 54 ++++++++++++++++++++----------------- 1 file changed, 29 insertions(+), 25 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 013cbc200579..bf92cd1805c2 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -378,6 +378,11 @@ struct dmar_domain { DECLARE_BITMAP(iommu_bmp, DMAR_UNITS_SUPPORTED); /* bitmap of iommus this domain uses*/ + u16 iommu_did[DMAR_UNITS_SUPPORTED]; + /* Domain ids per IOMMU. Use u16 since + * domain ids are 16 bit wide according + * to VT-d spec, section 9.3 */ + struct list_head devices; /* all devices' list */ struct iova_domain iovad; /* iova's that belong to this domain */ @@ -1543,11 +1548,13 @@ static int iommu_init_domains(struct intel_iommu *iommu) } /* - * if Caching mode is set, then invalid translations are tagged - * with domainid 0. Hence we need to pre-allocate it. + * If Caching mode is set, then invalid translations are tagged + * with domain-id 0, hence we need to pre-allocate it. We also + * use domain-id 0 as a marker for non-allocated domain-id, so + * make sure it is not used for a real domain. */ - if (cap_caching_mode(iommu->cap)) - set_bit(0, iommu->domain_ids); + set_bit(0, iommu->domain_ids); + return 0; } @@ -1560,9 +1567,10 @@ static void disable_dmar_iommu(struct intel_iommu *iommu) for_each_set_bit(i, iommu->domain_ids, cap_ndoms(iommu->cap)) { /* * Domain id 0 is reserved for invalid translation - * if hardware supports caching mode. + * if hardware supports caching mode and used as + * a non-allocated marker. */ - if (cap_caching_mode(iommu->cap) && i == 0) + if (i == 0) continue; domain = iommu->domains[i]; @@ -1624,6 +1632,7 @@ static int __iommu_attach_domain(struct dmar_domain *domain, if (num < ndomains) { set_bit(num, iommu->domain_ids); iommu->domains[num] = domain; + domain->iommu_did[iommu->seq_id] = num; } else { num = -ENOSPC; } @@ -1650,12 +1659,10 @@ static int iommu_attach_vm_domain(struct dmar_domain *domain, struct intel_iommu *iommu) { int num; - unsigned long ndomains; - ndomains = cap_ndoms(iommu->cap); - for_each_set_bit(num, iommu->domain_ids, ndomains) - if (iommu->domains[num] == domain) - return num; + num = domain->iommu_did[iommu->seq_id]; + if (num) + return num; return __iommu_attach_domain(domain, iommu); } @@ -1664,22 +1671,18 @@ static void iommu_detach_domain(struct dmar_domain *domain, struct intel_iommu *iommu) { unsigned long flags; - int num, ndomains; + int num; spin_lock_irqsave(&iommu->lock, flags); - if (domain_type_is_vm_or_si(domain)) { - ndomains = cap_ndoms(iommu->cap); - for_each_set_bit(num, iommu->domain_ids, ndomains) { - if (iommu->domains[num] == domain) { - clear_bit(num, iommu->domain_ids); - iommu->domains[num] = NULL; - break; - } - } - } else { - clear_bit(domain->id, iommu->domain_ids); - iommu->domains[domain->id] = NULL; - } + + num = domain->iommu_did[iommu->seq_id]; + + if (num == 0) + return; + + clear_bit(num, iommu->domain_ids); + iommu->domains[num] = NULL; + spin_unlock_irqrestore(&iommu->lock, flags); } @@ -1708,6 +1711,7 @@ static int domain_detach_iommu(struct dmar_domain *domain, if (test_and_clear_bit(iommu->seq_id, domain->iommu_bmp)) { count = --domain->iommu_count; domain_update_iommu_cap(domain); + domain->iommu_did[iommu->seq_id] = 0; } spin_unlock_irqrestore(&domain->iommu_lock, flags); -- 2.39.5