[PATCH v4 7/7] iommu/vt-d: Use real field for indication of first level

From: Lu Baolu
Date: Fri Nov 18 2022 - 08:33:22 EST


The dmar_domain uses bit field members to indicate the behaviors. Add
a bit field for using first level and remove the flags member to avoid
duplication.

Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
---
drivers/iommu/intel/iommu.h | 15 +++++----------
drivers/iommu/intel/iommu.c | 25 ++++++++++---------------
2 files changed, 15 insertions(+), 25 deletions(-)

diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h
index 92023dff9513..30b0d72aeb6c 100644
--- a/drivers/iommu/intel/iommu.h
+++ b/drivers/iommu/intel/iommu.h
@@ -517,14 +517,6 @@ struct context_entry {
u64 hi;
};

-/*
- * When VT-d works in the scalable mode, it allows DMA translation to
- * happen through either first level or second level page table. This
- * bit marks that the DMA translation for the domain goes through the
- * first level page table, otherwise, it goes through the second level.
- */
-#define DOMAIN_FLAG_USE_FIRST_LEVEL BIT(1)
-
struct iommu_domain_info {
struct intel_iommu *iommu;
unsigned int refcnt; /* Refcount of devices per iommu */
@@ -541,6 +533,11 @@ struct dmar_domain {
u8 iommu_coherency: 1; /* indicate coherency of iommu access */
u8 force_snooping : 1; /* Create IOPTEs with snoop control */
u8 set_pte_snp:1;
+ u8 use_first_level:1; /* DMA translation for the domain goes
+ * through the first level page table,
+ * otherwise, goes through the second
+ * level.
+ */

spinlock_t lock; /* Protect device tracking lists */
struct list_head devices; /* all devices' list */
@@ -550,8 +547,6 @@ struct dmar_domain {

/* adjusted guest address width, 0 is level 2 30-bit */
int agaw;
-
- int flags; /* flags to find out type of domain */
int iommu_superpage;/* Level of superpages supported:
0 == 4KiB (no superpages), 1 == 2MiB,
2 == 1GiB, 3 == 512GiB, 4 == 1TiB */
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 3b37f1b3b6de..a3db7ac3d60c 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -383,11 +383,6 @@ static inline int domain_type_is_si(struct dmar_domain *domain)
return domain->domain.type == IOMMU_DOMAIN_IDENTITY;
}

-static inline bool domain_use_first_level(struct dmar_domain *domain)
-{
- return domain->flags & DOMAIN_FLAG_USE_FIRST_LEVEL;
-}
-
static inline int domain_pfn_supported(struct dmar_domain *domain,
unsigned long pfn)
{
@@ -501,7 +496,7 @@ static int domain_update_iommu_superpage(struct dmar_domain *domain,
rcu_read_lock();
for_each_active_iommu(iommu, drhd) {
if (iommu != skip) {
- if (domain && domain_use_first_level(domain)) {
+ if (domain && domain->use_first_level) {
if (!cap_fl1gp_support(iommu->cap))
mask = 0x1;
} else {
@@ -579,7 +574,7 @@ static void domain_update_iommu_cap(struct dmar_domain *domain)
* paging and 57-bits with 5-level paging). Hence, skip bit
* [N-1].
*/
- if (domain_use_first_level(domain))
+ if (domain->use_first_level)
domain->domain.geometry.aperture_end = __DOMAIN_MAX_ADDR(domain->gaw - 1);
else
domain->domain.geometry.aperture_end = __DOMAIN_MAX_ADDR(domain->gaw);
@@ -947,7 +942,7 @@ static struct dma_pte *pfn_to_dma_pte(struct dmar_domain *domain,

domain_flush_cache(domain, tmp_page, VTD_PAGE_SIZE);
pteval = ((uint64_t)virt_to_dma_pfn(tmp_page) << VTD_PAGE_SHIFT) | DMA_PTE_READ | DMA_PTE_WRITE;
- if (domain_use_first_level(domain))
+ if (domain->use_first_level)
pteval |= DMA_FL_PTE_XD | DMA_FL_PTE_US | DMA_FL_PTE_ACCESS;

if (cmpxchg64(&pte->val, 0ULL, pteval))
@@ -1498,7 +1493,7 @@ static void iommu_flush_iotlb_psi(struct intel_iommu *iommu,
if (ih)
ih = 1 << 6;

- if (domain_use_first_level(domain)) {
+ if (domain->use_first_level) {
qi_flush_piotlb(iommu, did, PASID_RID2PASID, addr, pages, ih);
} else {
unsigned long bitmask = aligned_pages - 1;
@@ -1552,7 +1547,7 @@ static inline void __mapping_notify_one(struct intel_iommu *iommu,
* It's a non-present to present mapping. Only flush if caching mode
* and second level.
*/
- if (cap_caching_mode(iommu->cap) && !domain_use_first_level(domain))
+ if (cap_caching_mode(iommu->cap) && !domain->use_first_level)
iommu_flush_iotlb_psi(iommu, domain, pfn, pages, 0, 1);
else
iommu_flush_write_buffer(iommu);
@@ -1568,7 +1563,7 @@ static void intel_flush_iotlb_all(struct iommu_domain *domain)
struct intel_iommu *iommu = info->iommu;
u16 did = domain_id_iommu(dmar_domain, iommu);

- if (domain_use_first_level(dmar_domain))
+ if (dmar_domain->use_first_level)
qi_flush_piotlb(iommu, did, PASID_RID2PASID, 0, -1, 0);
else
iommu->flush.flush_iotlb(iommu, did, 0, 0,
@@ -1741,7 +1736,7 @@ static struct dmar_domain *alloc_domain(unsigned int type)

domain->nid = NUMA_NO_NODE;
if (first_level_by_default(type))
- domain->flags |= DOMAIN_FLAG_USE_FIRST_LEVEL;
+ domain->use_first_level = true;
domain->has_iotlb_device = false;
INIT_LIST_HEAD(&domain->devices);
spin_lock_init(&domain->lock);
@@ -2173,7 +2168,7 @@ __domain_mapping(struct dmar_domain *domain, unsigned long iov_pfn,

attr = prot & (DMA_PTE_READ | DMA_PTE_WRITE | DMA_PTE_SNP);
attr |= DMA_FL_PTE_PRESENT;
- if (domain_use_first_level(domain)) {
+ if (domain->use_first_level) {
attr |= DMA_FL_PTE_XD | DMA_FL_PTE_US | DMA_FL_PTE_ACCESS;
if (prot & DMA_PTE_WRITE)
attr |= DMA_FL_PTE_DIRTY;
@@ -2443,7 +2438,7 @@ static int dmar_domain_attach_device(struct dmar_domain *domain,
if (hw_pass_through && domain_type_is_si(domain))
ret = intel_pasid_setup_pass_through(iommu, domain,
dev, PASID_RID2PASID);
- else if (domain_use_first_level(domain))
+ else if (domain->use_first_level)
ret = domain_setup_first_level(iommu, domain, dev,
PASID_RID2PASID);
else
@@ -4412,7 +4407,7 @@ static void domain_set_force_snooping(struct dmar_domain *domain)
* Second level page table supports per-PTE snoop control. The
* iommu_map() interface will handle this by setting SNP bit.
*/
- if (!domain_use_first_level(domain)) {
+ if (!domain->use_first_level) {
domain->set_pte_snp = true;
return;
}
--
2.34.1