iommu.lists.linux-foundation.org archive mirror
 help / color / mirror / Atom feed
From: Lu Baolu <baolu.lu@linux.intel.com>
To: Joerg Roedel <joro@8bytes.org>
Cc: Kevin Tian <kevin.tian@intel.com>,
	iommu@lists.linux-foundation.org, Ashok Raj <ashok.raj@intel.com>
Subject: [PATCH 5/6] iommu/vt-d: Update scalable mode paging structure coherency
Date: Tue, 23 Jun 2020 07:13:44 +0800	[thread overview]
Message-ID: <20200622231345.29722-6-baolu.lu@linux.intel.com> (raw)
In-Reply-To: <20200622231345.29722-1-baolu.lu@linux.intel.com>

The Scalable-mode Page-walk Coherency (SMPWC) field in the VT-d extended
capability register indicates the hardware coherency behavior on paging
structures accessed through the pasid table entry. This is ignored in
current code and using ECAP.C instead which is only valid in legacy mode.
Fix this so that paging structure updates could be manually flushed from
the cache line if hardware page walking is not snooped.

Fixes: 765b6a98c1de3 ("iommu/vt-d: Enumerate the scalable mode capability")
Cc: Ashok Raj <ashok.raj@intel.com>
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
 drivers/iommu/intel/iommu.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index 66d07b1a3be2..f16bf63ea9fd 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -612,6 +612,12 @@ struct intel_iommu *domain_get_iommu(struct dmar_domain *domain)
 	return g_iommus[iommu_id];
 }
 
+static inline bool iommu_paging_structure_coherency(struct intel_iommu *iommu)
+{
+	return sm_supported(iommu) ?
+			ecap_smpwc(iommu->ecap) : ecap_coherent(iommu->ecap);
+}
+
 static void domain_update_iommu_coherency(struct dmar_domain *domain)
 {
 	struct dmar_drhd_unit *drhd;
@@ -623,7 +629,7 @@ static void domain_update_iommu_coherency(struct dmar_domain *domain)
 
 	for_each_domain_iommu(i, domain) {
 		found = true;
-		if (!ecap_coherent(g_iommus[i]->ecap)) {
+		if (!iommu_paging_structure_coherency(g_iommus[i])) {
 			domain->iommu_coherency = 0;
 			break;
 		}
@@ -634,7 +640,7 @@ static void domain_update_iommu_coherency(struct dmar_domain *domain)
 	/* No hardware attached; use lowest common denominator */
 	rcu_read_lock();
 	for_each_active_iommu(iommu, drhd) {
-		if (!ecap_coherent(iommu->ecap)) {
+		if (!iommu_paging_structure_coherency(iommu)) {
 			domain->iommu_coherency = 0;
 			break;
 		}
@@ -2094,7 +2100,8 @@ static int domain_context_mapping_one(struct dmar_domain *domain,
 
 	context_set_fault_enable(context);
 	context_set_present(context);
-	domain_flush_cache(domain, context, sizeof(*context));
+	if (!ecap_coherent(iommu->ecap))
+		clflush_cache_range(context, sizeof(*context));
 
 	/*
 	 * It's a non-present to present mapping. If hardware doesn't cache
-- 
2.17.1

_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

  parent reply	other threads:[~2020-06-22 23:18 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-06-22 23:13 [PATCH 0/6] [PULL REQUEST] iommu/vt-d: fixes for v5.8 Lu Baolu
2020-06-22 23:13 ` [PATCH 1/6] iommu/vt-d: Make Intel SVM code 64-bit only Lu Baolu
2020-06-22 23:13 ` [PATCH 2/6] iommu/vt-d: Set U/S bit in first level page table by default Lu Baolu
2020-06-22 23:13 ` [PATCH 3/6] iommu/vt-d: Don't apply gfx quirks to untrusted devices Lu Baolu
2020-06-22 23:13 ` [PATCH 4/6] iommu/vt-d: Enable PCI ACS for platform opt in hint Lu Baolu
2020-06-22 23:13 ` Lu Baolu [this message]
2020-06-22 23:13 ` [PATCH 6/6] iommu/vt-d: Fix misuse of iommu_domain_identity_map() Lu Baolu
2020-06-23  8:12 ` [PATCH 0/6] [PULL REQUEST] iommu/vt-d: fixes for v5.8 Joerg Roedel

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200622231345.29722-6-baolu.lu@linux.intel.com \
    --to=baolu.lu@linux.intel.com \
    --cc=ashok.raj@intel.com \
    --cc=iommu@lists.linux-foundation.org \
    --cc=joro@8bytes.org \
    --cc=kevin.tian@intel.com \
    --subject='Re: [PATCH 5/6] iommu/vt-d: Update scalable mode paging structure coherency' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).