iommu/vt-d: Implement page request handling

Largely based on the driver-mode implementation by Jesse Barnes.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
This commit is contained in:
David Woodhouse 2015-10-07 23:35:18 +01:00
parent 1208225cf4
commit a222a7f0bb
3 changed files with 220 additions and 1 deletions

View File

@ -1698,8 +1698,11 @@ static void free_dmar_iommu(struct intel_iommu *iommu)
free_context_table(iommu);
#ifdef CONFIG_INTEL_IOMMU_SVM
if (pasid_enabled(iommu))
if (pasid_enabled(iommu)) {
if (ecap_prs(iommu->ecap))
intel_svm_finish_prq(iommu);
intel_svm_free_pasid_tables(iommu);
}
#endif
}
@ -3243,6 +3246,13 @@ domains_done:
iommu_flush_write_buffer(iommu);
#ifdef CONFIG_INTEL_IOMMU_SVM
if (pasid_enabled(iommu) && ecap_prs(iommu->ecap)) {
ret = intel_svm_enable_prq(iommu);
if (ret)
goto free_iommu;
}
#endif
ret = dmar_set_interrupt(iommu);
if (ret)
goto free_iommu;
@ -4187,6 +4197,14 @@ static int intel_iommu_add(struct dmar_drhd_unit *dmaru)
intel_iommu_init_qi(iommu);
iommu_flush_write_buffer(iommu);
#ifdef CONFIG_INTEL_IOMMU_SVM
if (pasid_enabled(iommu) && ecap_prs(iommu->ecap)) {
ret = intel_svm_enable_prq(iommu);
if (ret)
goto disable_iommu;
}
#endif
ret = dmar_set_interrupt(iommu);
if (ret)
goto disable_iommu;
@ -4983,6 +5001,8 @@ int intel_iommu_enable_pasid(struct intel_iommu *iommu, struct intel_svm_dev *sd
ctx_lo |= CONTEXT_PASIDE;
if (iommu->pasid_state_table)
ctx_lo |= CONTEXT_DINVE;
if (info->pri_supported)
ctx_lo |= CONTEXT_PRS;
context[0].lo = ctx_lo;
wmb();
iommu->flush.flush_context(iommu, sdev->did, sdev->sid,

View File

@ -21,6 +21,10 @@
#include <linux/rculist.h>
#include <linux/pci.h>
#include <linux/pci-ats.h>
#include <linux/dmar.h>
#include <linux/interrupt.h>
static irqreturn_t prq_event_thread(int irq, void *d);
struct pasid_entry {
u64 val;
@ -82,6 +86,66 @@ int intel_svm_free_pasid_tables(struct intel_iommu *iommu)
return 0;
}
#define PRQ_ORDER 0
int intel_svm_enable_prq(struct intel_iommu *iommu)
{
struct page *pages;
int irq, ret;
pages = alloc_pages(GFP_KERNEL | __GFP_ZERO, PRQ_ORDER);
if (!pages) {
pr_warn("IOMMU: %s: Failed to allocate page request queue\n",
iommu->name);
return -ENOMEM;
}
iommu->prq = page_address(pages);
irq = dmar_alloc_hwirq(DMAR_UNITS_SUPPORTED + iommu->seq_id, iommu->node, iommu);
if (irq <= 0) {
pr_err("IOMMU: %s: Failed to create IRQ vector for page request queue\n",
iommu->name);
ret = -EINVAL;
err:
free_pages((unsigned long)iommu->prq, PRQ_ORDER);
iommu->prq = NULL;
return ret;
}
iommu->pr_irq = irq;
snprintf(iommu->prq_name, sizeof(iommu->prq_name), "dmar%d-prq", iommu->seq_id);
ret = request_threaded_irq(irq, NULL, prq_event_thread, IRQF_ONESHOT,
iommu->prq_name, iommu);
if (ret) {
pr_err("IOMMU: %s: Failed to request IRQ for page request queue\n",
iommu->name);
dmar_free_hwirq(irq);
goto err;
}
dmar_writeq(iommu->reg + DMAR_PQH_REG, 0ULL);
dmar_writeq(iommu->reg + DMAR_PQT_REG, 0ULL);
dmar_writeq(iommu->reg + DMAR_PQA_REG, virt_to_phys(iommu->prq) | PRQ_ORDER);
return 0;
}
int intel_svm_finish_prq(struct intel_iommu *iommu)
{
dmar_writeq(iommu->reg + DMAR_PQH_REG, 0ULL);
dmar_writeq(iommu->reg + DMAR_PQT_REG, 0ULL);
dmar_writeq(iommu->reg + DMAR_PQA_REG, 0ULL);
free_irq(iommu->pr_irq, iommu);
dmar_free_hwirq(iommu->pr_irq);
iommu->pr_irq = 0;
free_pages((unsigned long)iommu->prq, PRQ_ORDER);
iommu->prq = NULL;
return 0;
}
static void intel_flush_svm_range_dev (struct intel_svm *svm, struct intel_svm_dev *sdev,
unsigned long address, int pages, int ih)
{
@ -363,3 +427,112 @@ int intel_svm_unbind_mm(struct device *dev, int pasid)
return ret;
}
EXPORT_SYMBOL_GPL(intel_svm_unbind_mm);
/* Page request queue descriptor */
struct page_req_dsc {
u64 srr:1;
u64 bof:1;
u64 pasid_present:1;
u64 lpig:1;
u64 pasid:20;
u64 bus:8;
u64 private:23;
u64 prg_index:9;
u64 rd_req:1;
u64 wr_req:1;
u64 exe_req:1;
u64 priv_req:1;
u64 devfn:8;
u64 addr:52;
};
#define PRQ_RING_MASK ((0x1000 << PRQ_ORDER) - 0x10)
static irqreturn_t prq_event_thread(int irq, void *d)
{
struct intel_iommu *iommu = d;
struct intel_svm *svm = NULL;
int head, tail, handled = 0;
tail = dmar_readq(iommu->reg + DMAR_PQT_REG) & PRQ_RING_MASK;
head = dmar_readq(iommu->reg + DMAR_PQH_REG) & PRQ_RING_MASK;
while (head != tail) {
struct vm_area_struct *vma;
struct page_req_dsc *req;
struct qi_desc resp;
int ret, result;
u64 address;
handled = 1;
req = &iommu->prq[head / sizeof(*req)];
result = QI_RESP_FAILURE;
address = req->addr << PAGE_SHIFT;
if (!req->pasid_present) {
pr_err("%s: Page request without PASID: %08llx %08llx\n",
iommu->name, ((unsigned long long *)req)[0],
((unsigned long long *)req)[1]);
goto bad_req;
}
if (!svm || svm->pasid != req->pasid) {
rcu_read_lock();
svm = idr_find(&iommu->pasid_idr, req->pasid);
/* It *can't* go away, because the driver is not permitted
* to unbind the mm while any page faults are outstanding.
* So we only need RCU to protect the internal idr code. */
rcu_read_unlock();
if (!svm) {
pr_err("%s: Page request for invalid PASID %d: %08llx %08llx\n",
iommu->name, req->pasid, ((unsigned long long *)req)[0],
((unsigned long long *)req)[1]);
goto bad_req;
}
}
result = QI_RESP_INVALID;
down_read(&svm->mm->mmap_sem);
vma = find_extend_vma(svm->mm, address);
if (!vma || address < vma->vm_start)
goto invalid;
ret = handle_mm_fault(svm->mm, vma, address,
req->wr_req ? FAULT_FLAG_WRITE : 0);
if (ret & VM_FAULT_ERROR)
goto invalid;
result = QI_RESP_SUCCESS;
invalid:
up_read(&svm->mm->mmap_sem);
bad_req:
/* Accounting for major/minor faults? */
if (req->lpig) {
/* Page Group Response */
resp.low = 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, svm->iommu);
} 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) |
QI_PSTRM_RESP_CODE(result);
qi_submit_sync(&resp, svm->iommu);
}
head = (head + sizeof(*req)) & PRQ_RING_MASK;
}
dmar_writeq(iommu->reg + DMAR_PQH_REG, tail);
return IRQ_RETVAL(handled);
}

View File

@ -265,6 +265,8 @@ enum {
#define QI_EIOTLB_TYPE 0x6
#define QI_PC_TYPE 0x7
#define QI_DEIOTLB_TYPE 0x8
#define QI_PGRP_RESP_TYPE 0x9
#define QI_PSTRM_RESP_TYPE 0xa
#define QI_IEC_SELECTIVE (((u64)1) << 4)
#define QI_IEC_IIDEX(idx) (((u64)(idx & 0xffff) << 32))
@ -315,6 +317,25 @@ enum {
#define QI_DEV_EIOTLB_QDEP(qd) (((qd) & 0x1f) << 16)
#define QI_DEV_EIOTLB_MAX_INVS 32
#define QI_PGRP_IDX(idx) (((u64)(idx)) << 55)
#define QI_PGRP_PRIV(priv) (((u64)(priv)) << 32)
#define QI_PGRP_RESP_CODE(res) ((u64)(res))
#define QI_PGRP_PASID(pasid) (((u64)(pasid)) << 32)
#define QI_PGRP_DID(did) (((u64)(did)) << 16)
#define QI_PGRP_PASID_P(p) (((u64)(p)) << 4)
#define QI_PSTRM_ADDR(addr) (((u64)(addr)) & VTD_PAGE_MASK)
#define QI_PSTRM_DEVFN(devfn) (((u64)(devfn)) << 4)
#define QI_PSTRM_RESP_CODE(res) ((u64)(res))
#define QI_PSTRM_IDX(idx) (((u64)(idx)) << 55)
#define QI_PSTRM_PRIV(priv) (((u64)(priv)) << 32)
#define QI_PSTRM_BUS(bus) (((u64)(bus)) << 24)
#define QI_PSTRM_PASID(pasid) (((u64)(pasid)) << 4)
#define QI_RESP_SUCCESS 0x0
#define QI_RESP_INVALID 0x1
#define QI_RESP_FAILURE 0xf
#define QI_GRAN_ALL_ALL 0
#define QI_GRAN_NONG_ALL 1
#define QI_GRAN_NONG_PASID 2
@ -369,6 +390,7 @@ enum {
struct pasid_entry;
struct pasid_state_entry;
struct page_req_dsc;
struct intel_iommu {
void __iomem *reg; /* Pointer to hardware regs, virtual addr */
@ -401,6 +423,8 @@ struct intel_iommu {
* told to. But while it's all driver-arbitrated, we're fine. */
struct pasid_entry *pasid_table;
struct pasid_state_entry *pasid_state_table;
struct page_req_dsc *prq;
unsigned char prq_name[16]; /* Name for PRQ interrupt */
struct idr pasid_idr;
#endif
struct q_inval *qi; /* Queued invalidation info */
@ -445,6 +469,8 @@ extern int dmar_ir_support(void);
#ifdef CONFIG_INTEL_IOMMU_SVM
extern int intel_svm_alloc_pasid_tables(struct intel_iommu *iommu);
extern int intel_svm_free_pasid_tables(struct intel_iommu *iommu);
extern int intel_svm_enable_prq(struct intel_iommu *iommu);
extern int intel_svm_finish_prq(struct intel_iommu *iommu);
struct intel_svm_dev {
struct list_head list;