[PATCH v4 1/5] iommu/vt-d: Separate page request queue from SVM

Joel Granados
2024-10-15T21:08:29Z

IO page faults are no longer dependent on CONFIG_INTEL_IOMMU_SVM. Move
all Page Request Queue (PRQ) functions that handle prq events to a new
file in drivers/iommu/intel/prq.c. The page_req_des struct is now
declared in drivers/iommu/intel/prq.c.

No functional changes are intended. This is a preparation patch to
enable the use of IO page faults outside the SVM/PASID use cases.

Signed-off-by: Joel Granados <joel.granados@kernel.org>
---
drivers/iommu/intel/Makefile | 2 +-
drivers/iommu/intel/iommu.c | 20 +--
drivers/iommu/intel/iommu.h | 14 +-
drivers/iommu/intel/prq.c | 412 +++++++++++++++++++++++++++++++++++++++++++
drivers/iommu/intel/svm.c | 397 -----------------------------------------
5 files changed, 426 insertions(+), 419 deletions(-)

diff --git a/drivers/iommu/intel/Makefile b/drivers/iommu/intel/Makefile
index c8beb0281559..d3bb0798092d 100644
--- a/drivers/iommu/intel/Makefile
+++ b/drivers/iommu/intel/Makefile
@@ -1,6 +1,6 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_DMAR_TABLE) += dmar.o
-obj-$(CONFIG_INTEL_IOMMU) += iommu.o pasid.o nested.o cache.o
+obj-$(CONFIG_INTEL_IOMMU) += iommu.o pasid.o nested.o cache.o prq.o
obj-$(CONFIG_DMAR_TABLE) += trace.o cap_audit.o
obj-$(CONFIG_DMAR_PERF) += perf.o
obj-$(CONFIG_INTEL_IOMMU_DEBUGFS) += debugfs.o
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 9f6b0780f2ef..5d9c3333c92d 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -1428,12 +1428,10 @@ static void free_dmar_iommu(struct intel_iommu *iommu)
/* free context mapping */
free_context_table(iommu);

-#ifdef CONFIG_INTEL_IOMMU_SVM
if (pasid_supported(iommu)) {
if (ecap_prs(iommu->ecap))
- intel_svm_finish_prq(iommu);
+ intel_iommu_finish_prq(iommu);
}
-#endif
}

/*
@@ -2354,19 +2352,18 @@ static int __init init_dmars(void)

iommu_flush_write_buffer(iommu);

-#ifdef CONFIG_INTEL_IOMMU_SVM
if (pasid_supported(iommu) && ecap_prs(iommu->ecap)) {
/*
* Call dmar_alloc_hwirq() with dmar_global_lock held,
* could cause possible lock race condition.
*/
up_write(&dmar_global_lock);
- ret = intel_svm_enable_prq(iommu);
+ ret = intel_iommu_enable_prq(iommu);
down_write(&dmar_global_lock);
if (ret)
goto free_iommu;
}
-#endif
+
ret = dmar_set_interrupt(iommu);
if (ret)
goto free_iommu;
@@ -2786,13 +2783,12 @@ 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_supported(iommu) && ecap_prs(iommu->ecap)) {
- ret = intel_svm_enable_prq(iommu);
+ ret = intel_iommu_enable_prq(iommu);
if (ret)
goto disable_iommu;
}
-#endif
+
ret = dmar_set_interrupt(iommu);
if (ret)
goto disable_iommu;
@@ -4281,7 +4277,7 @@ static void intel_iommu_remove_dev_pasid(struct device *dev, ioasid_t pasid,
intel_iommu_debugfs_remove_dev_pasid(dev_pasid);
kfree(dev_pasid);
intel_pasid_tear_down_entry(iommu, dev, pasid, false);
- intel_drain_pasid_prq(dev, pasid);
+ intel_iommu_drain_pasid_prq(dev, pasid);
}

static int intel_iommu_set_dev_pasid(struct iommu_domain *domain,
@@ -4609,9 +4605,7 @@ const struct iommu_ops intel_iommu_ops = {
.def_domain_type = device_def_domain_type,
.remove_dev_pasid = intel_iommu_remove_dev_pasid,
.pgsize_bitmap = SZ_4K,
-#ifdef CONFIG_INTEL_IOMMU_SVM
- .page_response = intel_svm_page_response,
-#endif
+ .page_response = intel_iommu_page_response,
.default_domain_ops = &(const struct iommu_domain_ops) {
.attach_dev = intel_iommu_attach_device,
.set_dev_pasid = intel_iommu_set_dev_pasid,
diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h
index 1497f3112b12..7c3ef89ae959 100644
--- a/drivers/iommu/intel/iommu.h
+++ b/drivers/iommu/intel/iommu.h
@@ -730,12 +730,10 @@ struct intel_iommu {

struct iommu_flush flush;
#endif
-#ifdef CONFIG_INTEL_IOMMU_SVM
struct page_req_dsc *prq;
unsigned char prq_name[16]; /* Name for PRQ interrupt */
unsigned long prq_seq_number;
struct completion prq_complete;
-#endif
struct iopf_queue *iopf_queue;
unsigned char iopfq_name[16];
/* Synchronization between fault report and iommu device release. */
@@ -1278,18 +1276,18 @@ void intel_context_flush_present(struct device_domain_info *info,
struct context_entry *context,
u16 did, bool affect_domains);

+int intel_iommu_enable_prq(struct intel_iommu *iommu);
+int intel_iommu_finish_prq(struct intel_iommu *iommu);
+void intel_iommu_page_response(struct device *dev, struct iopf_fault *evt,
+ struct iommu_page_response *msg);
+void intel_iommu_drain_pasid_prq(struct device *dev, u32 pasid);
+
#ifdef CONFIG_INTEL_IOMMU_SVM
void intel_svm_check(struct intel_iommu *iommu);
-int intel_svm_enable_prq(struct intel_iommu *iommu);
-int intel_svm_finish_prq(struct intel_iommu *iommu);
-void intel_svm_page_response(struct device *dev, struct iopf_fault *evt,
- struct iommu_page_response *msg);
struct iommu_domain *intel_svm_domain_alloc(struct device *dev,
struct mm_struct *mm);
-void intel_drain_pasid_prq(struct device *dev, u32 pasid);
#else
static inline void intel_svm_check(struct intel_iommu *iommu) {}
-static inline void intel_drain_pasid_prq(struct device *dev, u32 pasid) {}
static inline struct iommu_domain *intel_svm_domain_alloc(struct device *dev,
struct mm_struct *mm)
{
diff --git a/drivers/iommu/intel/prq.c b/drivers/iommu/intel/prq.c
new file mode 100644
index 000000000000..d4f18eb46475
--- /dev/null
+++ b/drivers/iommu/intel/prq.c
@@ -0,0 +1,412 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright © 2015 Intel Corporation.
+ *
+ * Originally split from drivers/iommu/intel/svm.c
+ */
+
+#include <linux/pci.h>
+#include <linux/pci-ats.h>
+
+#include "iommu.h"
+#include "pasid.h"
+#include "../iommu-pages.h"
+#include "trace.h"
+
+/* Page request queue descriptor */
+struct page_req_dsc {
+ union {
+ struct {
+ u64 type:8;
+ u64 pasid_present:1;
+ u64 rsvd:7;
+ u64 rid:16;
+ u64 pasid:20;
+ u64 exe_req:1;
+ u64 pm_req:1;
+ u64 rsvd2:10;
+ };
+ u64 qw_0;
+ };
+ union {
+ struct {
+ u64 rd_req:1;
+ u64 wr_req:1;
+ u64 lpig:1;
+ u64 prg_index:9;
+ u64 addr:52;
+ };
+ u64 qw_1;
+ };
+ u64 qw_2;
+ u64 qw_3;
+};
+
+/**
+ * intel_iommu_drain_pasid_prq - Drain page requests and responses for a pasid
+ * @dev: target device
+ * @pasid: pasid for draining
+ *
+ * Drain all pending page requests and responses related to @pasid in both
+ * software and hardware. This is supposed to be called after the device
+ * driver has stopped DMA, the pasid entry has been cleared, and both IOTLB
+ * and DevTLB have been invalidated.
+ *
+ * It waits until all pending page requests for @pasid in the page fault
+ * queue are completed by the prq handling thread. Then follow the steps
+ * described in VT-d spec CH7.10 to drain all page requests and page
+ * responses pending in the hardware.
+ */
+void intel_iommu_drain_pasid_prq(struct device *dev, u32 pasid)
+{
+ struct device_domain_info *info;
+ struct dmar_domain *domain;
+ struct intel_iommu *iommu;
+ struct qi_desc desc[3];
+ struct pci_dev *pdev;
+ int head, tail;
+ u16 sid, did;
+ int qdep;
+
+ info = dev_iommu_priv_get(dev);
+ if (WARN_ON(!info || !dev_is_pci(dev)))
+ return;
+
+ if (!info->pri_enabled)
+ return;
+
+ iommu = info->iommu;
+ domain = info->domain;
+ pdev = to_pci_dev(dev);
+ sid = PCI_DEVID(info->bus, info->devfn);
+ did = domain ? domain_id_iommu(domain, iommu) : FLPT_DEFAULT_DID;
+
+ qdep = pci_ats_queue_depth(pdev);
+
+ /*
+ * Check and wait until all pending page requests in the queue are
+ * handled by the prq handling thread.
+ */
+prq_retry:
+ reinit_completion(&iommu->prq_complete);
+ 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 page_req_dsc *req;
+
+ req = &iommu->prq[head / sizeof(*req)];
+ if (!req->pasid_present || req->pasid != pasid) {
+ head = (head + sizeof(*req)) & PRQ_RING_MASK;
+ continue;
+ }
+
+ wait_for_completion(&iommu->prq_complete);
+ goto prq_retry;
+ }
+
+ iopf_queue_flush_dev(dev);
+
+ /*
+ * Perform steps described in VT-d spec CH7.10 to drain page
+ * requests and responses in hardware.
+ */
+ memset(desc, 0, sizeof(desc));
+ desc[0].qw0 = QI_IWD_STATUS_DATA(QI_DONE) |
+ QI_IWD_FENCE |
+ QI_IWD_TYPE;
+ desc[1].qw0 = QI_EIOTLB_PASID(pasid) |
+ QI_EIOTLB_DID(did) |
+ QI_EIOTLB_GRAN(QI_GRAN_NONG_PASID) |
+ QI_EIOTLB_TYPE;
+ desc[2].qw0 = QI_DEV_EIOTLB_PASID(pasid) |
+ QI_DEV_EIOTLB_SID(sid) |
+ QI_DEV_EIOTLB_QDEP(qdep) |
+ QI_DEIOTLB_TYPE |
+ QI_DEV_IOTLB_PFSID(info->pfsid);
+qi_retry:
+ reinit_completion(&iommu->prq_complete);
+ qi_submit_sync(iommu, desc, 3, QI_OPT_WAIT_DRAIN);
+ if (readl(iommu->reg + DMAR_PRS_REG) & DMA_PRS_PRO) {
+ wait_for_completion(&iommu->prq_complete);
+ goto qi_retry;
+ }
+}
+
+
+static bool is_canonical_address(u64 addr)
+{
+ int shift = 64 - (__VIRTUAL_MASK_SHIFT + 1);
+ long saddr = (long) addr;
+
+ return (((saddr << shift) >> shift) == saddr);
+}
+
+static void handle_bad_prq_event(struct intel_iommu *iommu,
+ struct page_req_dsc *req, int result)
+{
+ struct qi_desc desc = { };
+
+ pr_err("%s: Invalid page request: %08llx %08llx\n",
+ iommu->name, ((unsigned long long *)req)[0],
+ ((unsigned long long *)req)[1]);
+
+ if (!req->lpig)
+ return;
+
+ desc.qw0 = QI_PGRP_PASID(req->pasid) |
+ QI_PGRP_DID(req->rid) |
+ QI_PGRP_PASID_P(req->pasid_present) |
+ QI_PGRP_RESP_CODE(result) |
+ QI_PGRP_RESP_TYPE;
+ desc.qw1 = QI_PGRP_IDX(req->prg_index) |
+ QI_PGRP_LPIG(req->lpig);
+
+ qi_submit_sync(iommu, &desc, 1, 0);
+}
+
+static int prq_to_iommu_prot(struct page_req_dsc *req)
+{
+ int prot = 0;
+
+ if (req->rd_req)
+ prot |= IOMMU_FAULT_PERM_READ;
+ if (req->wr_req)
+ prot |= IOMMU_FAULT_PERM_WRITE;
+ if (req->exe_req)
+ prot |= IOMMU_FAULT_PERM_EXEC;
+ if (req->pm_req)
+ prot |= IOMMU_FAULT_PERM_PRIV;
+
+ return prot;
+}
+
+static void intel_prq_report(struct intel_iommu *iommu, struct device *dev,
+ struct page_req_dsc *desc)
+{
+ struct iopf_fault event = { };
+
+ /* Fill in event data for device specific processing */
+ event.fault.type = IOMMU_FAULT_PAGE_REQ;
+ event.fault.prm.addr = (u64)desc->addr << VTD_PAGE_SHIFT;
+ event.fault.prm.pasid = desc->pasid;
+ event.fault.prm.grpid = desc->prg_index;
+ event.fault.prm.perm = prq_to_iommu_prot(desc);
+
+ if (desc->lpig)
+ event.fault.prm.flags |= IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE;
+ if (desc->pasid_present) {
+ event.fault.prm.flags |= IOMMU_FAULT_PAGE_REQUEST_PASID_VALID;
+ event.fault.prm.flags |= IOMMU_FAULT_PAGE_RESPONSE_NEEDS_PASID;
+ }
+
+ iommu_report_device_fault(dev, &event);
+}
+
+static irqreturn_t prq_event_thread(int irq, void *d)
+{
+ struct intel_iommu *iommu = d;
+ struct page_req_dsc *req;
+ int head, tail, handled;
+ struct device *dev;
+ u64 address;
+
+ /*
+ * Clear PPR bit before reading head/tail registers, to ensure that
+ * we get a new interrupt if needed.
+ */
+ writel(DMA_PRS_PPR, iommu->reg + DMAR_PRS_REG);
+
+ tail = dmar_readq(iommu->reg + DMAR_PQT_REG) & PRQ_RING_MASK;
+ head = dmar_readq(iommu->reg + DMAR_PQH_REG) & PRQ_RING_MASK;
+ handled = (head != tail);
+ while (head != tail) {
+ req = &iommu->prq[head / sizeof(*req)];
+ address = (u64)req->addr << VTD_PAGE_SHIFT;
+
+ if (unlikely(!req->pasid_present)) {
+ pr_err("IOMMU: %s: Page request without PASID\n",
+ iommu->name);
+bad_req:
+ handle_bad_prq_event(iommu, req, QI_RESP_INVALID);
+ goto prq_advance;
+ }
+
+ if (unlikely(!is_canonical_address(address))) {
+ pr_err("IOMMU: %s: Address is not canonical\n",
+ iommu->name);
+ goto bad_req;
+ }
+
+ if (unlikely(req->pm_req && (req->rd_req | req->wr_req))) {
+ pr_err("IOMMU: %s: Page request in Privilege Mode\n",
+ iommu->name);
+ goto bad_req;
+ }
+
+ if (unlikely(req->exe_req && req->rd_req)) {
+ pr_err("IOMMU: %s: Execution request not supported\n",
+ iommu->name);
+ goto bad_req;
+ }
+
+ /* Drop Stop Marker message. No need for a response. */
+ if (unlikely(req->lpig && !req->rd_req && !req->wr_req))
+ goto prq_advance;
+
+ /*
+ * If prq is to be handled outside iommu driver via receiver of
+ * the fault notifiers, we skip the page response here.
+ */
+ mutex_lock(&iommu->iopf_lock);
+ dev = device_rbtree_find(iommu, req->rid);
+ if (!dev) {
+ mutex_unlock(&iommu->iopf_lock);
+ goto bad_req;
+ }
+
+ intel_prq_report(iommu, dev, req);
+ trace_prq_report(iommu, dev, req->qw_0, req->qw_1,
+ req->qw_2, req->qw_3,
+ iommu->prq_seq_number++);
+ mutex_unlock(&iommu->iopf_lock);
+prq_advance:
+ head = (head + sizeof(*req)) & PRQ_RING_MASK;
+ }
+
+ dmar_writeq(iommu->reg + DMAR_PQH_REG, tail);
+
+ /*
+ * Clear the page request overflow bit and wake up all threads that
+ * are waiting for the completion of this handling.
+ */
+ if (readl(iommu->reg + DMAR_PRS_REG) & DMA_PRS_PRO) {
+ pr_info_ratelimited("IOMMU: %s: PRQ overflow detected\n",
+ iommu->name);
+ head = dmar_readq(iommu->reg + DMAR_PQH_REG) & PRQ_RING_MASK;
+ tail = dmar_readq(iommu->reg + DMAR_PQT_REG) & PRQ_RING_MASK;
+ if (head == tail) {
+ iopf_queue_discard_partial(iommu->iopf_queue);
+ writel(DMA_PRS_PRO, iommu->reg + DMAR_PRS_REG);
+ pr_info_ratelimited("IOMMU: %s: PRQ overflow cleared",
+ iommu->name);
+ }
+ }
+
+ if (!completion_done(&iommu->prq_complete))
+ complete(&iommu->prq_complete);
+
+ return IRQ_RETVAL(handled);
+}
+
+int intel_iommu_enable_prq(struct intel_iommu *iommu)
+{
+ struct iopf_queue *iopfq;
+ int irq, ret;
+
+ iommu->prq = iommu_alloc_pages_node(iommu->node, GFP_KERNEL, PRQ_ORDER);
+ if (!iommu->prq) {
+ pr_warn("IOMMU: %s: Failed to allocate page request queue\n",
+ iommu->name);
+ return -ENOMEM;
+ }
+
+ irq = dmar_alloc_hwirq(IOMMU_IRQ_ID_OFFSET_PRQ + 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;
+ goto free_prq;
+ }
+ iommu->pr_irq = irq;
+
+ snprintf(iommu->iopfq_name, sizeof(iommu->iopfq_name),
+ "dmar%d-iopfq", iommu->seq_id);
+ iopfq = iopf_queue_alloc(iommu->iopfq_name);
+ if (!iopfq) {
+ pr_err("IOMMU: %s: Failed to allocate iopf queue\n", iommu->name);
+ ret = -ENOMEM;
+ goto free_hwirq;
+ }
+ iommu->iopf_queue = iopfq;
+
+ 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);
+ goto free_iopfq;
+ }
+ 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);
+
+ init_completion(&iommu->prq_complete);
+
+ return 0;
+
+free_iopfq:
+ iopf_queue_free(iommu->iopf_queue);
+ iommu->iopf_queue = NULL;
+free_hwirq:
+ dmar_free_hwirq(irq);
+ iommu->pr_irq = 0;
+free_prq:
+ iommu_free_pages(iommu->prq, PRQ_ORDER);
+ iommu->prq = NULL;
+
+ return ret;
+}
+
+int intel_iommu_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);
+
+ if (iommu->pr_irq) {
+ free_irq(iommu->pr_irq, iommu);
+ dmar_free_hwirq(iommu->pr_irq);
+ iommu->pr_irq = 0;
+ }
+
+ if (iommu->iopf_queue) {
+ iopf_queue_free(iommu->iopf_queue);
+ iommu->iopf_queue = NULL;
+ }
+
+ iommu_free_pages(iommu->prq, PRQ_ORDER);
+ iommu->prq = NULL;
+
+ return 0;
+}
+
+void intel_iommu_page_response(struct device *dev, struct iopf_fault *evt,
+ struct iommu_page_response *msg)
+{
+ struct device_domain_info *info = dev_iommu_priv_get(dev);
+ struct intel_iommu *iommu = info->iommu;
+ u8 bus = info->bus, devfn = info->devfn;
+ struct iommu_fault_page_request *prm;
+ struct qi_desc desc;
+ bool pasid_present;
+ bool last_page;
+ u16 sid;
+
+ prm = &evt->fault.prm;
+ sid = PCI_DEVID(bus, devfn);
+ pasid_present = prm->flags & IOMMU_FAULT_PAGE_REQUEST_PASID_VALID;
+ last_page = prm->flags & IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE;
+
+ desc.qw0 = QI_PGRP_PASID(prm->pasid) | QI_PGRP_DID(sid) |
+ QI_PGRP_PASID_P(pasid_present) |
+ QI_PGRP_RESP_CODE(msg->code) |
+ QI_PGRP_RESP_TYPE;
+ desc.qw1 = QI_PGRP_IDX(prm->grpid) | QI_PGRP_LPIG(last_page);
+ desc.qw2 = 0;
+ desc.qw3 = 0;
+
+ qi_submit_sync(iommu, &desc, 1, 0);
+}
+
diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
index 078d1e32a24e..3cc43a958b4d 100644
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -25,92 +25,6 @@
#include "../iommu-pages.h"
#include "trace.h"

-static irqreturn_t prq_event_thread(int irq, void *d);
-
-int intel_svm_enable_prq(struct intel_iommu *iommu)
-{
- struct iopf_queue *iopfq;
- int irq, ret;
-
- iommu->prq = iommu_alloc_pages_node(iommu->node, GFP_KERNEL, PRQ_ORDER);
- if (!iommu->prq) {
- pr_warn("IOMMU: %s: Failed to allocate page request queue\n",
- iommu->name);
- return -ENOMEM;
- }
-
- irq = dmar_alloc_hwirq(IOMMU_IRQ_ID_OFFSET_PRQ + 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;
- goto free_prq;
- }
- iommu->pr_irq = irq;
-
- snprintf(iommu->iopfq_name, sizeof(iommu->iopfq_name),
- "dmar%d-iopfq", iommu->seq_id);
- iopfq = iopf_queue_alloc(iommu->iopfq_name);
- if (!iopfq) {
- pr_err("IOMMU: %s: Failed to allocate iopf queue\n", iommu->name);
- ret = -ENOMEM;
- goto free_hwirq;
- }
- iommu->iopf_queue = iopfq;
-
- 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);
- goto free_iopfq;
- }
- 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);
-
- init_completion(&iommu->prq_complete);
-
- return 0;
-
-free_iopfq:
- iopf_queue_free(iommu->iopf_queue);
- iommu->iopf_queue = NULL;
-free_hwirq:
- dmar_free_hwirq(irq);
- iommu->pr_irq = 0;
-free_prq:
- iommu_free_pages(iommu->prq, PRQ_ORDER);
- iommu->prq = NULL;
-
- return ret;
-}
-
-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);
-
- if (iommu->pr_irq) {
- free_irq(iommu->pr_irq, iommu);
- dmar_free_hwirq(iommu->pr_irq);
- iommu->pr_irq = 0;
- }
-
- if (iommu->iopf_queue) {
- iopf_queue_free(iommu->iopf_queue);
- iommu->iopf_queue = NULL;
- }
-
- iommu_free_pages(iommu->prq, PRQ_ORDER);
- iommu->prq = NULL;
-
- return 0;
-}
-
void intel_svm_check(struct intel_iommu *iommu)
{
if (!pasid_supported(iommu))
@@ -240,317 +154,6 @@ static int intel_svm_set_dev_pasid(struct iommu_domain *domain,
return ret;
}

-/* Page request queue descriptor */
-struct page_req_dsc {
- union {
- struct {
- u64 type:8;
- u64 pasid_present:1;
- u64 rsvd:7;
- u64 rid:16;
- u64 pasid:20;
- u64 exe_req:1;
- u64 pm_req:1;
- u64 rsvd2:10;
- };
- u64 qw_0;
- };
- union {
- struct {
- u64 rd_req:1;
- u64 wr_req:1;
- u64 lpig:1;
- u64 prg_index:9;
- u64 addr:52;
- };
- u64 qw_1;
- };
- u64 qw_2;
- u64 qw_3;
-};
-
-static bool is_canonical_address(u64 addr)
-{
- int shift = 64 - (__VIRTUAL_MASK_SHIFT + 1);
- long saddr = (long) addr;
-
- return (((saddr << shift) >> shift) == saddr);
-}
-
-/**
- * intel_drain_pasid_prq - Drain page requests and responses for a pasid
- * @dev: target device
- * @pasid: pasid for draining
- *
- * Drain all pending page requests and responses related to @pasid in both
- * software and hardware. This is supposed to be called after the device
- * driver has stopped DMA, the pasid entry has been cleared, and both IOTLB
- * and DevTLB have been invalidated.
- *
- * It waits until all pending page requests for @pasid in the page fault
- * queue are completed by the prq handling thread. Then follow the steps
- * described in VT-d spec CH7.10 to drain all page requests and page
- * responses pending in the hardware.
- */
-void intel_drain_pasid_prq(struct device *dev, u32 pasid)
-{
- struct device_domain_info *info;
- struct dmar_domain *domain;
- struct intel_iommu *iommu;
- struct qi_desc desc[3];
- struct pci_dev *pdev;
- int head, tail;
- u16 sid, did;
- int qdep;
-
- info = dev_iommu_priv_get(dev);
- if (WARN_ON(!info || !dev_is_pci(dev)))
- return;
-
- if (!info->pri_enabled)
- return;
-
- iommu = info->iommu;
- domain = info->domain;
- pdev = to_pci_dev(dev);
- sid = PCI_DEVID(info->bus, info->devfn);
- did = domain ? domain_id_iommu(domain, iommu) : FLPT_DEFAULT_DID;
- qdep = pci_ats_queue_depth(pdev);
-
- /*
- * Check and wait until all pending page requests in the queue are
- * handled by the prq handling thread.
- */
-prq_retry:
- reinit_completion(&iommu->prq_complete);
- 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 page_req_dsc *req;
-
- req = &iommu->prq[head / sizeof(*req)];
- if (!req->pasid_present || req->pasid != pasid) {
- head = (head + sizeof(*req)) & PRQ_RING_MASK;
- continue;
- }
-
- wait_for_completion(&iommu->prq_complete);
- goto prq_retry;
- }
-
- iopf_queue_flush_dev(dev);
-
- /*
- * Perform steps described in VT-d spec CH7.10 to drain page
- * requests and responses in hardware.
- */
- memset(desc, 0, sizeof(desc));
- desc[0].qw0 = QI_IWD_STATUS_DATA(QI_DONE) |
- QI_IWD_FENCE |
- QI_IWD_TYPE;
- desc[1].qw0 = QI_EIOTLB_PASID(pasid) |
- QI_EIOTLB_DID(did) |
- QI_EIOTLB_GRAN(QI_GRAN_NONG_PASID) |
- QI_EIOTLB_TYPE;
- desc[2].qw0 = QI_DEV_EIOTLB_PASID(pasid) |
- QI_DEV_EIOTLB_SID(sid) |
- QI_DEV_EIOTLB_QDEP(qdep) |
- QI_DEIOTLB_TYPE |
- QI_DEV_IOTLB_PFSID(info->pfsid);
-qi_retry:
- reinit_completion(&iommu->prq_complete);
- qi_submit_sync(iommu, desc, 3, QI_OPT_WAIT_DRAIN);
- if (readl(iommu->reg + DMAR_PRS_REG) & DMA_PRS_PRO) {
- wait_for_completion(&iommu->prq_complete);
- goto qi_retry;
- }
-}
-
-static int prq_to_iommu_prot(struct page_req_dsc *req)
-{
- int prot = 0;
-
- if (req->rd_req)
- prot |= IOMMU_FAULT_PERM_READ;
- if (req->wr_req)
- prot |= IOMMU_FAULT_PERM_WRITE;
- if (req->exe_req)
- prot |= IOMMU_FAULT_PERM_EXEC;
- if (req->pm_req)
- prot |= IOMMU_FAULT_PERM_PRIV;
-
- return prot;
-}
-
-static void intel_svm_prq_report(struct intel_iommu *iommu, struct device *dev,
- struct page_req_dsc *desc)
-{
- struct iopf_fault event = { };
-
- /* Fill in event data for device specific processing */
- event.fault.type = IOMMU_FAULT_PAGE_REQ;
- event.fault.prm.addr = (u64)desc->addr << VTD_PAGE_SHIFT;
- event.fault.prm.pasid = desc->pasid;
- event.fault.prm.grpid = desc->prg_index;
- event.fault.prm.perm = prq_to_iommu_prot(desc);
-
- if (desc->lpig)
- event.fault.prm.flags |= IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE;
- if (desc->pasid_present) {
- event.fault.prm.flags |= IOMMU_FAULT_PAGE_REQUEST_PASID_VALID;
- event.fault.prm.flags |= IOMMU_FAULT_PAGE_RESPONSE_NEEDS_PASID;
- }
-
- iommu_report_device_fault(dev, &event);
-}
-
-static void handle_bad_prq_event(struct intel_iommu *iommu,
- struct page_req_dsc *req, int result)
-{
- struct qi_desc desc = { };
-
- pr_err("%s: Invalid page request: %08llx %08llx\n",
- iommu->name, ((unsigned long long *)req)[0],
- ((unsigned long long *)req)[1]);
-
- if (!req->lpig)
- return;
-
- desc.qw0 = QI_PGRP_PASID(req->pasid) |
- QI_PGRP_DID(req->rid) |
- QI_PGRP_PASID_P(req->pasid_present) |
- QI_PGRP_RESP_CODE(result) |
- QI_PGRP_RESP_TYPE;
- desc.qw1 = QI_PGRP_IDX(req->prg_index) |
- QI_PGRP_LPIG(req->lpig);
-
- qi_submit_sync(iommu, &desc, 1, 0);
-}
-
-static irqreturn_t prq_event_thread(int irq, void *d)
-{
- struct intel_iommu *iommu = d;
- struct page_req_dsc *req;
- int head, tail, handled;
- struct device *dev;
- u64 address;
-
- /*
- * Clear PPR bit before reading head/tail registers, to ensure that
- * we get a new interrupt if needed.
- */
- writel(DMA_PRS_PPR, iommu->reg + DMAR_PRS_REG);
-
- tail = dmar_readq(iommu->reg + DMAR_PQT_REG) & PRQ_RING_MASK;
- head = dmar_readq(iommu->reg + DMAR_PQH_REG) & PRQ_RING_MASK;
- handled = (head != tail);
- while (head != tail) {
- req = &iommu->prq[head / sizeof(*req)];
- address = (u64)req->addr << VTD_PAGE_SHIFT;
-
- if (unlikely(!req->pasid_present)) {
- pr_err("IOMMU: %s: Page request without PASID\n",
- iommu->name);
-bad_req:
- handle_bad_prq_event(iommu, req, QI_RESP_INVALID);
- goto prq_advance;
- }
-
- if (unlikely(!is_canonical_address(address))) {
- pr_err("IOMMU: %s: Address is not canonical\n",
- iommu->name);
- goto bad_req;
- }
-
- if (unlikely(req->pm_req && (req->rd_req | req->wr_req))) {
- pr_err("IOMMU: %s: Page request in Privilege Mode\n",
- iommu->name);
- goto bad_req;
- }
-
- if (unlikely(req->exe_req && req->rd_req)) {
- pr_err("IOMMU: %s: Execution request not supported\n",
- iommu->name);
- goto bad_req;
- }
-
- /* Drop Stop Marker message. No need for a response. */
- if (unlikely(req->lpig && !req->rd_req && !req->wr_req))
- goto prq_advance;
-
- /*
- * If prq is to be handled outside iommu driver via receiver of
- * the fault notifiers, we skip the page response here.
- */
- mutex_lock(&iommu->iopf_lock);
- dev = device_rbtree_find(iommu, req->rid);
- if (!dev) {
- mutex_unlock(&iommu->iopf_lock);
- goto bad_req;
- }
-
- intel_svm_prq_report(iommu, dev, req);
- trace_prq_report(iommu, dev, req->qw_0, req->qw_1,
- req->qw_2, req->qw_3,
- iommu->prq_seq_number++);
- mutex_unlock(&iommu->iopf_lock);
-prq_advance:
- head = (head + sizeof(*req)) & PRQ_RING_MASK;
- }
-
- dmar_writeq(iommu->reg + DMAR_PQH_REG, tail);
-
- /*
- * Clear the page request overflow bit and wake up all threads that
- * are waiting for the completion of this handling.
- */
- if (readl(iommu->reg + DMAR_PRS_REG) & DMA_PRS_PRO) {
- pr_info_ratelimited("IOMMU: %s: PRQ overflow detected\n",
- iommu->name);
- head = dmar_readq(iommu->reg + DMAR_PQH_REG) & PRQ_RING_MASK;
- tail = dmar_readq(iommu->reg + DMAR_PQT_REG) & PRQ_RING_MASK;
- if (head == tail) {
- iopf_queue_discard_partial(iommu->iopf_queue);
- writel(DMA_PRS_PRO, iommu->reg + DMAR_PRS_REG);
- pr_info_ratelimited("IOMMU: %s: PRQ overflow cleared",
- iommu->name);
- }
- }
-
- if (!completion_done(&iommu->prq_complete))
- complete(&iommu->prq_complete);
-
- return IRQ_RETVAL(handled);
-}
-
-void intel_svm_page_response(struct device *dev, struct iopf_fault *evt,
- struct iommu_page_response *msg)
-{
- struct device_domain_info *info = dev_iommu_priv_get(dev);
- struct intel_iommu *iommu = info->iommu;
- u8 bus = info->bus, devfn = info->devfn;
- struct iommu_fault_page_request *prm;
- struct qi_desc desc;
- bool pasid_present;
- bool last_page;
- u16 sid;
-
- prm = &evt->fault.prm;
- sid = PCI_DEVID(bus, devfn);
- pasid_present = prm->flags & IOMMU_FAULT_PAGE_REQUEST_PASID_VALID;
- last_page = prm->flags & IOMMU_FAULT_PAGE_REQUEST_LAST_PAGE;
-
- desc.qw0 = QI_PGRP_PASID(prm->pasid) | QI_PGRP_DID(sid) |
- QI_PGRP_PASID_P(pasid_present) |
- QI_PGRP_RESP_CODE(msg->code) |
- QI_PGRP_RESP_TYPE;
- desc.qw1 = QI_PGRP_IDX(prm->grpid) | QI_PGRP_LPIG(last_page);
- desc.qw2 = 0;
- desc.qw3 = 0;
-
- qi_submit_sync(iommu, &desc, 1, 0);
-}
-
static void intel_svm_domain_free(struct iommu_domain *domain)
{
struct dmar_domain *dmar_domain = to_dmar_domain(domain);

--
2.43.0