1

iommu/vt-d: Add qi_batch for dmar_domain

Introduces a qi_batch structure to hold batched cache invalidation
descriptors on a per-dmar_domain basis. A fixed-size descriptor
array is used for simplicity. The qi_batch is allocated when the
first cache tag is added to the domain and freed during
iommu_free_domain().

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Link: https://lore.kernel.org/r/20240815065221.50328-4-tina.zhang@intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Lu Baolu 2024-09-02 10:27:23 +08:00 committed by Joerg Roedel
parent 3297d047cd
commit 777cdd8534
5 changed files with 27 additions and 1 deletions

View File

@ -190,6 +190,13 @@ int cache_tag_assign_domain(struct dmar_domain *domain,
u16 did = domain_get_id_for_dev(domain, dev);
int ret;
/* domain->qi_bach will be freed in iommu_free_domain() path. */
if (!domain->qi_batch) {
domain->qi_batch = kzalloc(sizeof(*domain->qi_batch), GFP_KERNEL);
if (!domain->qi_batch)
return -ENOMEM;
}
ret = __cache_tag_assign_domain(domain, did, dev, pasid);
if (ret || domain->domain.type != IOMMU_DOMAIN_NESTED)
return ret;

View File

@ -1572,6 +1572,7 @@ static void domain_exit(struct dmar_domain *domain)
if (WARN_ON(!list_empty(&domain->devices)))
return;
kfree(domain->qi_batch);
kfree(domain);
}

View File

@ -584,6 +584,19 @@ struct iommu_domain_info {
* to VT-d spec, section 9.3 */
};
/*
* We start simply by using a fixed size for the batched descriptors. This
* size is currently sufficient for our needs. Future improvements could
* involve dynamically allocating the batch buffer based on actual demand,
* allowing us to adjust the batch size for optimal performance in different
* scenarios.
*/
#define QI_MAX_BATCHED_DESC_COUNT 16
struct qi_batch {
struct qi_desc descs[QI_MAX_BATCHED_DESC_COUNT];
unsigned int index;
};
struct dmar_domain {
int nid; /* node id */
struct xarray iommu_array; /* Attached IOMMU array */
@ -608,6 +621,7 @@ struct dmar_domain {
spinlock_t cache_lock; /* Protect the cache tag list */
struct list_head cache_tags; /* Cache tag list */
struct qi_batch *qi_batch; /* Batched QI descriptors */
int iommu_superpage;/* Level of superpages supported:
0 == 4KiB (no superpages), 1 == 2MiB,

View File

@ -83,6 +83,7 @@ static void intel_nested_domain_free(struct iommu_domain *domain)
spin_lock(&s2_domain->s1_lock);
list_del(&dmar_domain->s2_link);
spin_unlock(&s2_domain->s1_lock);
kfree(dmar_domain->qi_batch);
kfree(dmar_domain);
}

View File

@ -184,7 +184,10 @@ static void intel_mm_release(struct mmu_notifier *mn, struct mm_struct *mm)
static void intel_mm_free_notifier(struct mmu_notifier *mn)
{
kfree(container_of(mn, struct dmar_domain, notifier));
struct dmar_domain *domain = container_of(mn, struct dmar_domain, notifier);
kfree(domain->qi_batch);
kfree(domain);
}
static const struct mmu_notifier_ops intel_mmuops = {