iommu/vt-d: Replace iommu_bmp with a refcount
This replaces the dmar_domain->iommu_bmp with a similar
reference count array. This allows us to keep track of how
many devices behind each iommu are attached to the domain.
This is necessary for further simplifications and
optimizations to the iommu<->domain attachment code.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 91f0c3d..a5aa957 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -373,10 +373,16 @@
/* si_domain contains mulitple devices */
#define DOMAIN_FLAG_STATIC_IDENTITY (1 << 1)
+#define for_each_domain_iommu(idx, domain) \
+ for (idx = 0; idx < g_num_of_iommus; idx++) \
+ if (domain->iommu_refcnt[idx])
+
struct dmar_domain {
int nid; /* node id */
- DECLARE_BITMAP(iommu_bmp, DMAR_UNITS_SUPPORTED);
- /* bitmap of iommus this domain uses*/
+
+ unsigned iommu_refcnt[DMAR_UNITS_SUPPORTED];
+ /* Refcount of devices per iommu */
+
u16 iommu_did[DMAR_UNITS_SUPPORTED];
/* Domain ids per IOMMU. Use u16 since
@@ -699,7 +705,9 @@
/* si_domain and vm domain should not get here. */
BUG_ON(domain_type_is_vm_or_si(domain));
- iommu_id = find_first_bit(domain->iommu_bmp, g_num_of_iommus);
+ for_each_domain_iommu(iommu_id, domain)
+ break;
+
if (iommu_id < 0 || iommu_id >= g_num_of_iommus)
return NULL;
@@ -715,7 +723,7 @@
domain->iommu_coherency = 1;
- for_each_set_bit(i, domain->iommu_bmp, g_num_of_iommus) {
+ for_each_domain_iommu(i, domain) {
found = true;
if (!ecap_coherent(g_iommus[i]->ecap)) {
domain->iommu_coherency = 0;
@@ -1607,25 +1615,26 @@
static void disable_dmar_iommu(struct intel_iommu *iommu)
{
- struct dmar_domain *domain;
- int i;
+ struct device_domain_info *info, *tmp;
- if ((iommu->domains) && (iommu->domain_ids)) {
- 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 and used as
- * a non-allocated marker.
- */
- if (i == 0)
- continue;
+ if (!iommu->domains || !iommu->domain_ids)
+ return;
- domain = get_iommu_domain(iommu, i);
- clear_bit(i, iommu->domain_ids);
- if (domain_detach_iommu(domain, iommu) == 0 &&
- !domain_type_is_vm(domain))
- domain_exit(domain);
- }
+ list_for_each_entry_safe(info, tmp, &device_domain_list, global) {
+ struct dmar_domain *domain;
+
+ if (info->iommu != iommu)
+ continue;
+
+ if (!info->dev || !info->domain)
+ continue;
+
+ domain = info->domain;
+
+ domain_remove_one_dev_info(domain, info->dev);
+
+ if (!domain_type_is_vm_or_si(domain))
+ domain_exit(domain);
}
if (iommu->gcmd & DMA_GCMD_TE)
@@ -1734,10 +1743,10 @@
unsigned long flags;
spin_lock_irqsave(&domain->iommu_lock, flags);
- if (!test_and_set_bit(iommu->seq_id, domain->iommu_bmp)) {
- domain->iommu_count++;
- if (domain->iommu_count == 1)
- domain->nid = iommu->node;
+ domain->iommu_refcnt[iommu->seq_id] += 1;
+ domain->iommu_count += 1;
+ if (domain->iommu_refcnt[iommu->seq_id] == 1) {
+ domain->nid = iommu->node;
domain_update_iommu_cap(domain);
}
spin_unlock_irqrestore(&domain->iommu_lock, flags);
@@ -1750,8 +1759,9 @@
int count = INT_MAX;
spin_lock_irqsave(&domain->iommu_lock, flags);
- if (test_and_clear_bit(iommu->seq_id, domain->iommu_bmp)) {
- count = --domain->iommu_count;
+ domain->iommu_refcnt[iommu->seq_id] -= 1;
+ count = --domain->iommu_count;
+ if (domain->iommu_refcnt[iommu->seq_id] == 0) {
domain_update_iommu_cap(domain);
domain->iommu_did[iommu->seq_id] = 0;
}
@@ -1876,9 +1886,8 @@
static void domain_exit(struct dmar_domain *domain)
{
- struct dmar_drhd_unit *drhd;
- struct intel_iommu *iommu;
struct page *freelist = NULL;
+ int i;
/* Domain 0 is reserved, so dont process it */
if (!domain)
@@ -1898,10 +1907,8 @@
/* clear attached or cached domains */
rcu_read_lock();
- for_each_active_iommu(iommu, drhd)
- if (domain_type_is_vm(domain) ||
- test_bit(iommu->seq_id, domain->iommu_bmp))
- iommu_detach_domain(domain, iommu);
+ for_each_domain_iommu(i, domain)
+ iommu_detach_domain(domain, g_iommus[i]);
rcu_read_unlock();
dma_free_pagelist(freelist);
@@ -4633,9 +4640,10 @@
continue;
}
- /* if there is no other devices under the same iommu
- * owned by this domain, clear this iommu in iommu_bmp
- * update iommu count and coherency
+ /*
+ * If there is no other devices under the same iommu owned by
+ * this domain, clear this iommu in iommu_refcnt update iommu
+ * count and coherency.
*/
if (info->iommu == iommu)
found = true;
@@ -4843,7 +4851,7 @@
npages = last_pfn - start_pfn + 1;
- for_each_set_bit(iommu_id, dmar_domain->iommu_bmp, g_num_of_iommus) {
+ for_each_domain_iommu(iommu_id, dmar_domain) {
iommu = g_iommus[iommu_id];
/*