iommu/vt-d: Add custom allocator for IOASID

When VT-d driver runs in the guest, PASID allocation must be
performed via virtual command interface. This patch registers a
custom IOASID allocator which takes precedence over the default
XArray based allocator. The resulting IOASID allocation will always
come from the host. This ensures that PASID namespace is system-
wide.

Virtual command registers are used in the guest only, to prevent
vmexit cost, we cache the capability and store it during initialization.

Signed-off-by: Liu, Yi L <yi.l.liu@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20200516062101.29541-9-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
This commit is contained in:
Jacob Pan
2020-05-16 14:20:51 +08:00
committed by Joerg Roedel
parent 24f27d32ab
commit 3375303e82
3 changed files with 93 additions and 0 deletions

View File

@@ -19,6 +19,7 @@
#include <linux/iommu.h>
#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/dmar.h>
#include <linux/ioasid.h>
#include <asm/cacheflush.h>
#include <asm/iommu.h>
@@ -195,6 +196,9 @@
#define ecap_max_handle_mask(e) ((e >> 20) & 0xf)
#define ecap_sc_support(e) ((e >> 7) & 0x1) /* Snooping Control */
/* Virtual command interface capability */
#define vccap_pasid(v) (((v) & DMA_VCS_PAS)) /* PASID allocation */
/* IOTLB_REG */
#define DMA_TLB_FLUSH_GRANU_OFFSET 60
#define DMA_TLB_GLOBAL_FLUSH (((u64)1) << 60)
@@ -288,6 +292,7 @@
/* PRS_REG */
#define DMA_PRS_PPR ((u32)1)
#define DMA_VCS_PAS ((u64)1)
#define IOMMU_WAIT_OP(iommu, offset, op, cond, sts) \
do { \
@@ -555,6 +560,7 @@ struct intel_iommu {
u64 reg_size; /* size of hw register set */
u64 cap;
u64 ecap;
u64 vccap;
u32 gcmd; /* Holds TE, EAFL. Don't need SRTP, SFL, WBF */
raw_spinlock_t register_lock; /* protect register handling */
int seq_id; /* sequence id of the iommu */
@@ -575,6 +581,7 @@ struct intel_iommu {
#ifdef CONFIG_INTEL_IOMMU_SVM
struct page_req_dsc *prq;
unsigned char prq_name[16]; /* Name for PRQ interrupt */
struct ioasid_allocator_ops pasid_allocator; /* Custom allocator for PASIDs */
#endif
struct q_inval *qi; /* Queued invalidation info */
u32 *iommu_state; /* Store iommu states between suspend and resume.*/