[PATCH v6 04/12] iommu/vt-d: Add 256-bit invalidation descriptor support

Lu Baolu
2018-12-10T01:58:58Z

Intel vt-d spec rev3.0 requires software to use 256-bit
descriptors in invalidation queue. As the spec reads in
section 6.5.2:

Remapping hardware supporting Scalable Mode Translations
(ECAP_REG.SMTS=1) allow software to additionally program
the width of the descriptors (128-bits or 256-bits) that
will be written into the Queue. Software should setup the
Invalidation Queue for 256-bit descriptors before progra-
mming remapping hardware for scalable-mode translation as
128-bit descriptors are treated as invalid descriptors
(see Table 21 in Section 6.5.2.10) in scalable-mode.

This patch adds 256-bit invalidation descriptor support
if the hardware presents scalable mode capability.

Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Sanjay Kumar <sanjay.k.kumar@intel.com>
Signed-off-by: Liu Yi L <yi.l.liu@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
drivers/iommu/dmar.c | 91 +++++++++++++++++++----------
drivers/iommu/intel-svm.c | 76 +++++++++++++++---------
drivers/iommu/intel_irq_remapping.c | 6 +-
include/linux/intel-iommu.h | 9 ++-
4 files changed, 121 insertions(+), 61 deletions(-)

diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c
index d9c748b6f9e4..9511f9aeb77c 100644
--- a/drivers/iommu/dmar.c
+++ b/drivers/iommu/dmar.c
@@ -1160,6 +1160,7 @@ static int qi_check_fault(struct intel_iommu *iommu, int index)
int head, tail;
struct q_inval *qi = iommu->qi;
int wait_index = (index + 1) % QI_LENGTH;
+ int shift = qi_shift(iommu);

if (qi->desc_status[wait_index] == QI_ABORT)
return -EAGAIN;
@@ -1173,13 +1174,19 @@ static int qi_check_fault(struct intel_iommu *iommu, int index)
*/
if (fault & DMA_FSTS_IQE) {
head = readl(iommu->reg + DMAR_IQH_REG);
- if ((head >> DMAR_IQ_SHIFT) == index) {
- pr_err("VT-d detected invalid descriptor: "
- "low=%llx, high=%llx\n",
- (unsigned long long)qi->desc[index].low,
- (unsigned long long)qi->desc[index].high);
- memcpy(&qi->desc[index], &qi->desc[wait_index],
- sizeof(struct qi_desc));
+ if ((head >> shift) == index) {
+ struct qi_desc *desc = qi->desc + head;
+
+ /*
+ * desc->qw2 and desc->qw3 are either reserved or
+ * used by software as private data. We won't print
+ * out these two qw's for security consideration.
+ */
+ pr_err("VT-d detected invalid descriptor: qw0 = %llx, qw1 = %llx\n",
+ (unsigned long long)desc->qw0,
+ (unsigned long long)desc->qw1);
+ memcpy(desc, qi->desc + (wait_index << shift),
+ 1 << shift);
writel(DMA_FSTS_IQE, iommu->reg + DMAR_FSTS_REG);
return -EINVAL;
}
@@ -1191,10 +1198,10 @@ static int qi_check_fault(struct intel_iommu *iommu, int index)
*/
if (fault & DMA_FSTS_ITE) {
head = readl(iommu->reg + DMAR_IQH_REG);
- head = ((head >> DMAR_IQ_SHIFT) - 1 + QI_LENGTH) % QI_LENGTH;
+ head = ((head >> shift) - 1 + QI_LENGTH) % QI_LENGTH;
head |= 1;
tail = readl(iommu->reg + DMAR_IQT_REG);
- tail = ((tail >> DMAR_IQ_SHIFT) - 1 + QI_LENGTH) % QI_LENGTH;
+ tail = ((tail >> shift) - 1 + QI_LENGTH) % QI_LENGTH;

writel(DMA_FSTS_ITE, iommu->reg + DMAR_FSTS_REG);

@@ -1222,15 +1229,14 @@ int qi_submit_sync(struct qi_desc *desc, struct intel_iommu *iommu)
{
int rc;
struct q_inval *qi = iommu->qi;
- struct qi_desc *hw, wait_desc;
+ int offset, shift, length;
+ struct qi_desc wait_desc;
int wait_index, index;
unsigned long flags;

if (!qi)
return 0;

- hw = qi->desc;
-
restart:
rc = 0;

@@ -1243,16 +1249,21 @@ int qi_submit_sync(struct qi_desc *desc, struct intel_iommu *iommu)

index = qi->free_head;
wait_index = (index + 1) % QI_LENGTH;
+ shift = qi_shift(iommu);
+ length = 1 << shift;

qi->desc_status[index] = qi->desc_status[wait_index] = QI_IN_USE;

- hw[index] = *desc;
-
- wait_desc.low = QI_IWD_STATUS_DATA(QI_DONE) |
+ offset = index << shift;
+ memcpy(qi->desc + offset, desc, length);
+ wait_desc.qw0 = QI_IWD_STATUS_DATA(QI_DONE) |
QI_IWD_STATUS_WRITE | QI_IWD_TYPE;
- wait_desc.high = virt_to_phys(&qi->desc_status[wait_index]);
+ wait_desc.qw1 = virt_to_phys(&qi->desc_status[wait_index]);
+ wait_desc.qw2 = 0;
+ wait_desc.qw3 = 0;

- hw[wait_index] = wait_desc;
+ offset = wait_index << shift;
+ memcpy(qi->desc + offset, &wait_desc, length);

qi->free_head = (qi->free_head + 2) % QI_LENGTH;
qi->free_cnt -= 2;
@@ -1261,7 +1272,7 @@ int qi_submit_sync(struct qi_desc *desc, struct intel_iommu *iommu)
* update the HW tail register indicating the presence of
* new descriptors.
*/
- writel(qi->free_head << DMAR_IQ_SHIFT, iommu->reg + DMAR_IQT_REG);
+ writel(qi->free_head << shift, iommu->reg + DMAR_IQT_REG);

while (qi->desc_status[wait_index] != QI_DONE) {
/*
@@ -1298,8 +1309,10 @@ void qi_global_iec(struct intel_iommu *iommu)
{
struct qi_desc desc;

- desc.low = QI_IEC_TYPE;
- desc.high = 0;
+ desc.qw0 = QI_IEC_TYPE;
+ desc.qw1 = 0;
+ desc.qw2 = 0;
+ desc.qw3 = 0;

/* should never fail */
qi_submit_sync(&desc, iommu);
@@ -1310,9 +1323,11 @@ void qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid, u8 fm,
{
struct qi_desc desc;

- desc.low = QI_CC_FM(fm) | QI_CC_SID(sid) | QI_CC_DID(did)
+ desc.qw0 = QI_CC_FM(fm) | QI_CC_SID(sid) | QI_CC_DID(did)
| QI_CC_GRAN(type) | QI_CC_TYPE;
- desc.high = 0;
+ desc.qw1 = 0;
+ desc.qw2 = 0;
+ desc.qw3 = 0;

qi_submit_sync(&desc, iommu);
}
@@ -1331,10 +1346,12 @@ void qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64 addr,
if (cap_read_drain(iommu->cap))
dr = 1;

- desc.low = QI_IOTLB_DID(did) | QI_IOTLB_DR(dr) | QI_IOTLB_DW(dw)
+ desc.qw0 = QI_IOTLB_DID(did) | QI_IOTLB_DR(dr) | QI_IOTLB_DW(dw)
| QI_IOTLB_GRAN(type) | QI_IOTLB_TYPE;
- desc.high = QI_IOTLB_ADDR(addr) | QI_IOTLB_IH(ih)
+ desc.qw1 = QI_IOTLB_ADDR(addr) | QI_IOTLB_IH(ih)
| QI_IOTLB_AM(size_order);
+ desc.qw2 = 0;
+ desc.qw3 = 0;

qi_submit_sync(&desc, iommu);
}
@@ -1347,15 +1364,17 @@ void qi_flush_dev_iotlb(struct intel_iommu *iommu, u16 sid, u16 pfsid,
if (mask) {
WARN_ON_ONCE(addr & ((1ULL << (VTD_PAGE_SHIFT + mask)) - 1));
addr |= (1ULL << (VTD_PAGE_SHIFT + mask - 1)) - 1;
- desc.high = QI_DEV_IOTLB_ADDR(addr) | QI_DEV_IOTLB_SIZE;
+ desc.qw1 = QI_DEV_IOTLB_ADDR(addr) | QI_DEV_IOTLB_SIZE;
} else
- desc.high = QI_DEV_IOTLB_ADDR(addr);
+ desc.qw1 = QI_DEV_IOTLB_ADDR(addr);

if (qdep >= QI_DEV_IOTLB_MAX_INVS)
qdep = 0;

- desc.low = QI_DEV_IOTLB_SID(sid) | QI_DEV_IOTLB_QDEP(qdep) |
+ desc.qw0 = QI_DEV_IOTLB_SID(sid) | QI_DEV_IOTLB_QDEP(qdep) |
QI_DIOTLB_TYPE | QI_DEV_IOTLB_PFSID(pfsid);
+ desc.qw2 = 0;
+ desc.qw3 = 0;

qi_submit_sync(&desc, iommu);
}
@@ -1403,16 +1422,24 @@ static void __dmar_enable_qi(struct intel_iommu *iommu)
u32 sts;
unsigned long flags;
struct q_inval *qi = iommu->qi;
+ u64 val = virt_to_phys(qi->desc);

qi->free_head = qi->free_tail = 0;
qi->free_cnt = QI_LENGTH;

+ /*
+ * Set DW=1 and QS=1 in IQA_REG when Scalable Mode capability
+ * is present.
+ */
+ if (ecap_smts(iommu->ecap))
+ val |= (1 << 11) | 1;
+
raw_spin_lock_irqsave(&iommu->register_lock, flags);

/* write zero to the tail reg */
writel(0, iommu->reg + DMAR_IQT_REG);

- dmar_writeq(iommu->reg + DMAR_IQA_REG, virt_to_phys(qi->desc));
+ dmar_writeq(iommu->reg + DMAR_IQA_REG, val);

iommu->gcmd |= DMA_GCMD_QIE;
writel(iommu->gcmd, iommu->reg + DMAR_GCMD_REG);
@@ -1448,8 +1475,12 @@ int dmar_enable_qi(struct intel_iommu *iommu)

qi = iommu->qi;

-
- desc_page = alloc_pages_node(iommu->node, GFP_ATOMIC | __GFP_ZERO, 0);
+ /*
+ * Need two pages to accommodate 256 descriptors of 256 bits each
+ * if the remapping hardware supports scalable mode translation.
+ */
+ desc_page = alloc_pages_node(iommu->node, GFP_ATOMIC | __GFP_ZERO,
+ !!ecap_smts(iommu->ecap));
if (!desc_page) {
kfree(qi);
iommu->qi = NULL;
diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c
index 9014b07ab975..9b6771a89207 100644
--- a/drivers/iommu/intel-svm.c
+++ b/drivers/iommu/intel-svm.c
@@ -161,27 +161,40 @@ static void intel_flush_svm_range_dev (struct intel_svm *svm, struct intel_svm_d
* because that's the only option the hardware gives us. Despite
* the fact that they are actually only accessible through one. */
if (gl)
- desc.low = QI_EIOTLB_PASID(svm->pasid) | QI_EIOTLB_DID(sdev->did) |
- QI_EIOTLB_GRAN(QI_GRAN_ALL_ALL) | QI_EIOTLB_TYPE;
+ desc.qw0 = QI_EIOTLB_PASID(svm->pasid) |
+ QI_EIOTLB_DID(sdev->did) |
+ QI_EIOTLB_GRAN(QI_GRAN_ALL_ALL) |
+ QI_EIOTLB_TYPE;
else
- desc.low = QI_EIOTLB_PASID(svm->pasid) | QI_EIOTLB_DID(sdev->did) |
- QI_EIOTLB_GRAN(QI_GRAN_NONG_PASID) | QI_EIOTLB_TYPE;
- desc.high = 0;
+ desc.qw0 = QI_EIOTLB_PASID(svm->pasid) |
+ QI_EIOTLB_DID(sdev->did) |
+ QI_EIOTLB_GRAN(QI_GRAN_NONG_PASID) |
+ QI_EIOTLB_TYPE;
+ desc.qw1 = 0;
} else {
int mask = ilog2(__roundup_pow_of_two(pages));

- desc.low = QI_EIOTLB_PASID(svm->pasid) | QI_EIOTLB_DID(sdev->did) |
- QI_EIOTLB_GRAN(QI_GRAN_PSI_PASID) | QI_EIOTLB_TYPE;
- desc.high = QI_EIOTLB_ADDR(address) | QI_EIOTLB_GL(gl) |
- QI_EIOTLB_IH(ih) | QI_EIOTLB_AM(mask);
+ desc.qw0 = QI_EIOTLB_PASID(svm->pasid) |
+ QI_EIOTLB_DID(sdev->did) |
+ QI_EIOTLB_GRAN(QI_GRAN_PSI_PASID) |
+ QI_EIOTLB_TYPE;
+ desc.qw1 = QI_EIOTLB_ADDR(address) |
+ QI_EIOTLB_GL(gl) |
+ QI_EIOTLB_IH(ih) |
+ QI_EIOTLB_AM(mask);
}
+ desc.qw2 = 0;
+ desc.qw3 = 0;
qi_submit_sync(&desc, svm->iommu);

if (sdev->dev_iotlb) {
- desc.low = QI_DEV_EIOTLB_PASID(svm->pasid) | QI_DEV_EIOTLB_SID(sdev->sid) |
- QI_DEV_EIOTLB_QDEP(sdev->qdep) | QI_DEIOTLB_TYPE;
+ desc.qw0 = QI_DEV_EIOTLB_PASID(svm->pasid) |
+ QI_DEV_EIOTLB_SID(sdev->sid) |
+ QI_DEV_EIOTLB_QDEP(sdev->qdep) |
+ QI_DEIOTLB_TYPE;
if (pages == -1) {
- desc.high = QI_DEV_EIOTLB_ADDR(-1ULL >> 1) | QI_DEV_EIOTLB_SIZE;
+ desc.qw1 = QI_DEV_EIOTLB_ADDR(-1ULL >> 1) |
+ QI_DEV_EIOTLB_SIZE;
} else if (pages > 1) {
/* The least significant zero bit indicates the size. So,
* for example, an "address" value of 0x12345f000 will
@@ -189,10 +202,13 @@ static void intel_flush_svm_range_dev (struct intel_svm *svm, struct intel_svm_d
unsigned long last = address + ((unsigned long)(pages - 1) << VTD_PAGE_SHIFT);
unsigned long mask = __rounddown_pow_of_two(address ^ last);

- desc.high = QI_DEV_EIOTLB_ADDR((address & ~mask) | (mask - 1)) | QI_DEV_EIOTLB_SIZE;
+ desc.qw1 = QI_DEV_EIOTLB_ADDR((address & ~mask) |
+ (mask - 1)) | QI_DEV_EIOTLB_SIZE;
} else {
- desc.high = QI_DEV_EIOTLB_ADDR(address);
+ desc.qw1 = QI_DEV_EIOTLB_ADDR(address);
}
+ desc.qw2 = 0;
+ desc.qw3 = 0;
qi_submit_sync(&desc, svm->iommu);
}
}
@@ -237,8 +253,11 @@ static void intel_flush_pasid_dev(struct intel_svm *svm, struct intel_svm_dev *s
{
struct qi_desc desc;

- desc.high = 0;
- desc.low = QI_PC_TYPE | QI_PC_DID(sdev->did) | QI_PC_PASID_SEL | QI_PC_PASID(pasid);
+ desc.qw0 = QI_PC_TYPE | QI_PC_DID(sdev->did) |
+ QI_PC_PASID_SEL | QI_PC_PASID(pasid);
+ desc.qw1 = 0;
+ desc.qw2 = 0;
+ desc.qw3 = 0;

qi_submit_sync(&desc, svm->iommu);
}
@@ -667,24 +686,27 @@ static irqreturn_t prq_event_thread(int irq, void *d)
no_pasid:
if (req->lpig) {
/* Page Group Response */
- resp.low = QI_PGRP_PASID(req->pasid) |
+ resp.qw0 = QI_PGRP_PASID(req->pasid) |
QI_PGRP_DID((req->bus << 8) | req->devfn) |
QI_PGRP_PASID_P(req->pasid_present) |
QI_PGRP_RESP_TYPE;
- resp.high = QI_PGRP_IDX(req->prg_index) |
- QI_PGRP_PRIV(req->private) | QI_PGRP_RESP_CODE(result);
-
- qi_submit_sync(&resp, iommu);
+ resp.qw1 = QI_PGRP_IDX(req->prg_index) |
+ QI_PGRP_PRIV(req->private) |
+ QI_PGRP_RESP_CODE(result);
} else if (req->srr) {
/* Page Stream Response */
- resp.low = QI_PSTRM_IDX(req->prg_index) |
- QI_PSTRM_PRIV(req->private) | QI_PSTRM_BUS(req->bus) |
- QI_PSTRM_PASID(req->pasid) | QI_PSTRM_RESP_TYPE;
- resp.high = QI_PSTRM_ADDR(address) | QI_PSTRM_DEVFN(req->devfn) |
+ resp.qw0 = QI_PSTRM_IDX(req->prg_index) |
+ QI_PSTRM_PRIV(req->private) |
+ QI_PSTRM_BUS(req->bus) |
+ QI_PSTRM_PASID(req->pasid) |
+ QI_PSTRM_RESP_TYPE;
+ resp.qw1 = QI_PSTRM_ADDR(address) |
+ QI_PSTRM_DEVFN(req->devfn) |
QI_PSTRM_RESP_CODE(result);
-
- qi_submit_sync(&resp, iommu);
}
+ resp.qw2 = 0;
+ resp.qw3 = 0;
+ qi_submit_sync(&resp, iommu);

head = (head + sizeof(*req)) & PRQ_RING_MASK;
}
diff --git a/drivers/iommu/intel_irq_remapping.c b/drivers/iommu/intel_irq_remapping.c
index c2d6c11431de..24d45b07f425 100644
--- a/drivers/iommu/intel_irq_remapping.c
+++ b/drivers/iommu/intel_irq_remapping.c
@@ -145,9 +145,11 @@ static int qi_flush_iec(struct intel_iommu *iommu, int index, int mask)
{
struct qi_desc desc;

- desc.low = QI_IEC_IIDEX(index) | QI_IEC_TYPE | QI_IEC_IM(mask)
+ desc.qw0 = QI_IEC_IIDEX(index) | QI_IEC_TYPE | QI_IEC_IM(mask)
| QI_IEC_SELECTIVE;
- desc.high = 0;
+ desc.qw1 = 0;
+ desc.qw2 = 0;
+ desc.qw3 = 0;

return qi_submit_sync(&desc, iommu);
}
diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index b4da61385ebf..08ff588a4df7 100644
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -401,13 +401,18 @@ enum {
#define QI_GRAN_NONG_PASID 2
#define QI_GRAN_PSI_PASID 3

+#define qi_shift(iommu) (DMAR_IQ_SHIFT + !!ecap_smts((iommu)->ecap))
+
struct qi_desc {
- u64 low, high;
+ u64 qw0;
+ u64 qw1;
+ u64 qw2;
+ u64 qw3;
};

struct q_inval {
raw_spinlock_t q_lock;
- struct qi_desc *desc; /* invalidation queue */
+ void *desc; /* invalidation queue */
int *desc_status; /* desc status */
int free_head; /* first free entry */
int free_tail; /* last free entry */
--
2.17.1