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path: root/drivers/pci/dmar.c
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Diffstat (limited to 'drivers/pci/dmar.c')
-rw-r--r--drivers/pci/dmar.c73
1 files changed, 56 insertions, 17 deletions
diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c
index 519f5f9..5f33340 100644
--- a/drivers/pci/dmar.c
+++ b/drivers/pci/dmar.c
@@ -332,6 +332,14 @@ parse_dmar_table(void)
entry_header = (struct acpi_dmar_header *)(dmar + 1);
while (((unsigned long)entry_header) <
(((unsigned long)dmar) + dmar_tbl->length)) {
+ /* Avoid looping forever on bad ACPI tables */
+ if (entry_header->length == 0) {
+ printk(KERN_WARNING PREFIX
+ "Invalid 0-length structure\n");
+ ret = -EINVAL;
+ break;
+ }
+
dmar_table_print_dmar_entry(entry_header);
switch (entry_header->type) {
@@ -494,7 +502,7 @@ int alloc_iommu(struct dmar_drhd_unit *drhd)
int map_size;
u32 ver;
static int iommu_allocated = 0;
- int agaw;
+ int agaw = 0;
iommu = kzalloc(sizeof(*iommu), GFP_KERNEL);
if (!iommu)
@@ -510,6 +518,7 @@ int alloc_iommu(struct dmar_drhd_unit *drhd)
iommu->cap = dmar_readq(iommu->reg + DMAR_CAP_REG);
iommu->ecap = dmar_readq(iommu->reg + DMAR_ECAP_REG);
+#ifdef CONFIG_DMAR
agaw = iommu_calculate_agaw(iommu);
if (agaw < 0) {
printk(KERN_ERR
@@ -517,6 +526,7 @@ int alloc_iommu(struct dmar_drhd_unit *drhd)
iommu->seq_id);
goto error;
}
+#endif
iommu->agaw = agaw;
/* the registers might be more than one page */
@@ -574,19 +584,49 @@ static inline void reclaim_free_desc(struct q_inval *qi)
}
}
+static int qi_check_fault(struct intel_iommu *iommu, int index)
+{
+ u32 fault;
+ int head;
+ struct q_inval *qi = iommu->qi;
+ int wait_index = (index + 1) % QI_LENGTH;
+
+ fault = readl(iommu->reg + DMAR_FSTS_REG);
+
+ /*
+ * If IQE happens, the head points to the descriptor associated
+ * with the error. No new descriptors are fetched until the IQE
+ * is cleared.
+ */
+ if (fault & DMA_FSTS_IQE) {
+ head = readl(iommu->reg + DMAR_IQH_REG);
+ if ((head >> 4) == index) {
+ memcpy(&qi->desc[index], &qi->desc[wait_index],
+ sizeof(struct qi_desc));
+ __iommu_flush_cache(iommu, &qi->desc[index],
+ sizeof(struct qi_desc));
+ writel(DMA_FSTS_IQE, iommu->reg + DMAR_FSTS_REG);
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
/*
* Submit the queued invalidation descriptor to the remapping
* hardware unit and wait for its completion.
*/
-void qi_submit_sync(struct qi_desc *desc, struct intel_iommu *iommu)
+int qi_submit_sync(struct qi_desc *desc, struct intel_iommu *iommu)
{
+ int rc = 0;
struct q_inval *qi = iommu->qi;
struct qi_desc *hw, wait_desc;
int wait_index, index;
unsigned long flags;
if (!qi)
- return;
+ return 0;
hw = qi->desc;
@@ -604,7 +644,8 @@ void qi_submit_sync(struct qi_desc *desc, struct intel_iommu *iommu)
hw[index] = *desc;
- wait_desc.low = QI_IWD_STATUS_DATA(2) | QI_IWD_STATUS_WRITE | QI_IWD_TYPE;
+ wait_desc.low = QI_IWD_STATUS_DATA(QI_DONE) |
+ QI_IWD_STATUS_WRITE | QI_IWD_TYPE;
wait_desc.high = virt_to_phys(&qi->desc_status[wait_index]);
hw[wait_index] = wait_desc;
@@ -615,13 +656,11 @@ void qi_submit_sync(struct qi_desc *desc, struct intel_iommu *iommu)
qi->free_head = (qi->free_head + 2) % QI_LENGTH;
qi->free_cnt -= 2;
- spin_lock(&iommu->register_lock);
/*
* update the HW tail register indicating the presence of
* new descriptors.
*/
writel(qi->free_head << 4, iommu->reg + DMAR_IQT_REG);
- spin_unlock(&iommu->register_lock);
while (qi->desc_status[wait_index] != QI_DONE) {
/*
@@ -631,15 +670,21 @@ void qi_submit_sync(struct qi_desc *desc, struct intel_iommu *iommu)
* a deadlock where the interrupt context can wait indefinitely
* for free slots in the queue.
*/
+ rc = qi_check_fault(iommu, index);
+ if (rc)
+ goto out;
+
spin_unlock(&qi->q_lock);
cpu_relax();
spin_lock(&qi->q_lock);
}
-
- qi->desc_status[index] = QI_DONE;
+out:
+ qi->desc_status[index] = qi->desc_status[wait_index] = QI_DONE;
reclaim_free_desc(qi);
spin_unlock_irqrestore(&qi->q_lock, flags);
+
+ return rc;
}
/*
@@ -652,13 +697,13 @@ void qi_global_iec(struct intel_iommu *iommu)
desc.low = QI_IEC_TYPE;
desc.high = 0;
+ /* should never fail */
qi_submit_sync(&desc, iommu);
}
int qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid, u8 fm,
u64 type, int non_present_entry_flush)
{
-
struct qi_desc desc;
if (non_present_entry_flush) {
@@ -672,10 +717,7 @@ int qi_flush_context(struct intel_iommu *iommu, u16 did, u16 sid, u8 fm,
| QI_CC_GRAN(type) | QI_CC_TYPE;
desc.high = 0;
- qi_submit_sync(&desc, iommu);
-
- return 0;
-
+ return qi_submit_sync(&desc, iommu);
}
int qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64 addr,
@@ -705,10 +747,7 @@ int qi_flush_iotlb(struct intel_iommu *iommu, u16 did, u64 addr,
desc.high = QI_IOTLB_ADDR(addr) | QI_IOTLB_IH(ih)
| QI_IOTLB_AM(size_order);
- qi_submit_sync(&desc, iommu);
-
- return 0;
-
+ return qi_submit_sync(&desc, iommu);
}
/*
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