Commit 2c3262f9 authored by Lu Baolu's avatar Lu Baolu Committed by Joerg Roedel
Browse files

iommu/vt-d: Acquiring lock in domain ID allocation helpers 



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.

Signed-off-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20220706025524.2904370-7-baolu.lu@linux.intel.com


Signed-off-by: default avatarJoerg Roedel <jroedel@suse.de>
parent ffd5869d

drivers/iommu/intel/iommu.c

+9 −15
Original line number Diff line number Diff line
@@ -1779,16 +1779,13 @@ 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);
@@ -1797,7 +1794,8 @@ 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);
@@ -1806,7 +1804,9 @@ 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,
@@ -1814,9 +1814,7 @@ 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];
@@ -1824,6 +1822,7 @@ 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)
@@ -2472,9 +2471,7 @@ static int domain_add_dev_info(struct dmar_domain *domain, struct device *dev) 


	spin_lock(&device_domain_lock);

	info->domain = domain;

	spin_lock(&iommu->lock);

	ret = domain_attach_iommu(domain, iommu);

	spin_unlock(&iommu->lock);

	if (ret) {

		spin_unlock(&device_domain_lock);

		return ret;
@@ -4178,10 +4175,7 @@ static void __dmar_remove_one_dev_info(struct device_domain_info *info) 
	}



	list_del(&info->link);



	spin_lock(&iommu->lock);

	domain_detach_iommu(domain, iommu);

	spin_unlock(&iommu->lock);

}



static void dmar_remove_one_dev_info(struct device *dev)