The iommu->lock is used to protect the per-IOMMU domain ID resource. Moving the lock into the ID alloc/free helpers makes the code more compact. At the same time, the device_domain_lock is irrelevant to the domain ID resource, remove its assertion as well.
On the other hand, the iommu->lock is never used in interrupt context, there's no need to use the irqsave variant of the spinlock calls. Signed-off-by: Lu Baolu <baolu...@linux.intel.com> --- drivers/iommu/intel/iommu.c | 25 +++++++++---------------- 1 file changed, 9 insertions(+), 16 deletions(-) diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index b2ef8af0c3f3..8fdaa01ef10d 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -1782,16 +1782,13 @@ static struct dmar_domain *alloc_domain(unsigned int type) return domain; } -/* Must be called with iommu->lock */ static int domain_attach_iommu(struct dmar_domain *domain, struct intel_iommu *iommu) { unsigned long ndomains; - int num; - - assert_spin_locked(&device_domain_lock); - assert_spin_locked(&iommu->lock); + int num, ret = 0; + spin_lock(&iommu->lock); domain->iommu_refcnt[iommu->seq_id] += 1; if (domain->iommu_refcnt[iommu->seq_id] == 1) { ndomains = cap_ndoms(iommu->cap); @@ -1800,7 +1797,8 @@ static int domain_attach_iommu(struct dmar_domain *domain, if (num >= ndomains) { pr_err("%s: No free domain ids\n", iommu->name); domain->iommu_refcnt[iommu->seq_id] -= 1; - return -ENOSPC; + ret = -ENOSPC; + goto out_unlock; } set_bit(num, iommu->domain_ids); @@ -1809,7 +1807,9 @@ static int domain_attach_iommu(struct dmar_domain *domain, domain_update_iommu_cap(domain); } - return 0; +out_unlock: + spin_unlock(&iommu->lock); + return ret; } static void domain_detach_iommu(struct dmar_domain *domain, @@ -1817,9 +1817,7 @@ static void domain_detach_iommu(struct dmar_domain *domain, { int num; - assert_spin_locked(&device_domain_lock); - assert_spin_locked(&iommu->lock); - + spin_lock(&iommu->lock); domain->iommu_refcnt[iommu->seq_id] -= 1; if (domain->iommu_refcnt[iommu->seq_id] == 0) { num = domain->iommu_did[iommu->seq_id]; @@ -1827,6 +1825,7 @@ static void domain_detach_iommu(struct dmar_domain *domain, domain_update_iommu_cap(domain); domain->iommu_did[iommu->seq_id] = 0; } + spin_unlock(&iommu->lock); } static inline int guestwidth_to_adjustwidth(int gaw) @@ -2479,9 +2478,7 @@ static int domain_add_dev_info(struct dmar_domain *domain, struct device *dev) spin_lock_irqsave(&device_domain_lock, flags); info->domain = domain; - spin_lock(&iommu->lock); ret = domain_attach_iommu(domain, iommu); - spin_unlock(&iommu->lock); if (ret) { spin_unlock_irqrestore(&device_domain_lock, flags); return ret; @@ -4166,7 +4163,6 @@ static void __dmar_remove_one_dev_info(struct device_domain_info *info) { struct dmar_domain *domain; struct intel_iommu *iommu; - unsigned long flags; assert_spin_locked(&device_domain_lock); @@ -4187,10 +4183,7 @@ static void __dmar_remove_one_dev_info(struct device_domain_info *info) } list_del(&info->link); - - spin_lock_irqsave(&iommu->lock, flags); domain_detach_iommu(domain, iommu); - spin_unlock_irqrestore(&iommu->lock, flags); } static void dmar_remove_one_dev_info(struct device *dev) -- 2.25.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu