IOMMU Archive on lore.kernel.org
 help / color / Atom feed
From: Logan Gunthorpe <logang@deltatee.com>
To: linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org,
	Joerg Roedel <joro@8bytes.org>
Cc: Logan Gunthorpe <logang@deltatee.com>, Kit Chow <kchow@gigaio.com>
Subject: [PATCH 3/3] iommu/amd: Support multiple PCI DMA aliases in IRQ Remapping
Date: Tue,  8 Oct 2019 16:18:37 -0600
Message-ID: <20191008221837.13067-4-logang@deltatee.com> (raw)
In-Reply-To: <20191008221837.13067-1-logang@deltatee.com>

Non-Transparent Bridge (NTB) devices (among others) may have many DMA
aliases seeing the hardware will send requests with different device ids
depending on their origin across the bridged hardware.

See commit ad281ecf1c7d ("PCI: Add DMA alias quirk for Microsemi Switchtec
NTB") for more information on this.

The AMD IOMMU IRQ remapping functionality ignores all PCI aliases for
IRQs so if devices send an interrupt from one of their aliases they
will be blocked on AMD hardware with the IOMMU enabled.

To fix this, ensure IRQ remapping is enabled for all aliases with
MSI interrupts.

This is analogous to the functionality added to the Intel IRQ remapping
code in commit 3f0c625c6ae7 ("iommu/vt-d: Allow interrupts from the entire
bus for aliased devices")

Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
---
 drivers/iommu/amd_iommu.c | 46 +++++++++++++++++++++++++++++++++------
 1 file changed, 39 insertions(+), 7 deletions(-)

diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c
index 1f15f0bae5b3..f8a6fa8d639b 100644
--- a/drivers/iommu/amd_iommu.c
+++ b/drivers/iommu/amd_iommu.c
@@ -3758,7 +3758,27 @@ static void set_remap_table_entry(struct amd_iommu *iommu, u16 devid,
 	iommu_flush_dte(iommu, devid);
 }
 
-static struct irq_remap_table *alloc_irq_table(u16 devid)
+static int set_remap_table_entry_alias(struct pci_dev *pdev, u16 alias,
+				       void *data)
+{
+	struct irq_remap_table *table = data;
+
+	irq_lookup_table[alias] = table;
+	set_dte_irq_entry(alias, table);
+
+	return 0;
+}
+
+static int iommu_flush_dte_alias(struct pci_dev *pdev, u16 alias, void *data)
+{
+	struct amd_iommu *iommu = data;
+
+	iommu_flush_dte(iommu, alias);
+
+	return 0;
+}
+
+static struct irq_remap_table *alloc_irq_table(u16 devid, struct pci_dev *pdev)
 {
 	struct irq_remap_table *table = NULL;
 	struct irq_remap_table *new_table = NULL;
@@ -3804,7 +3824,14 @@ static struct irq_remap_table *alloc_irq_table(u16 devid)
 	table = new_table;
 	new_table = NULL;
 
-	set_remap_table_entry(iommu, devid, table);
+	if (pdev) {
+		pci_for_each_dma_alias(pdev, set_remap_table_entry_alias,
+				       table);
+		pci_for_each_dma_alias(pdev, iommu_flush_dte_alias, iommu);
+	} else {
+		set_remap_table_entry(iommu, devid, table);
+	}
+
 	if (devid != alias)
 		set_remap_table_entry(iommu, alias, table);
 
@@ -3821,7 +3848,8 @@ static struct irq_remap_table *alloc_irq_table(u16 devid)
 	return table;
 }
 
-static int alloc_irq_index(u16 devid, int count, bool align)
+static int alloc_irq_index(u16 devid, int count, bool align,
+			   struct pci_dev *pdev)
 {
 	struct irq_remap_table *table;
 	int index, c, alignment = 1;
@@ -3831,7 +3859,7 @@ static int alloc_irq_index(u16 devid, int count, bool align)
 	if (!iommu)
 		return -ENODEV;
 
-	table = alloc_irq_table(devid);
+	table = alloc_irq_table(devid, pdev);
 	if (!table)
 		return -ENODEV;
 
@@ -4264,7 +4292,7 @@ static int irq_remapping_alloc(struct irq_domain *domain, unsigned int virq,
 		struct irq_remap_table *table;
 		struct amd_iommu *iommu;
 
-		table = alloc_irq_table(devid);
+		table = alloc_irq_table(devid, NULL);
 		if (table) {
 			if (!table->min_index) {
 				/*
@@ -4281,11 +4309,15 @@ static int irq_remapping_alloc(struct irq_domain *domain, unsigned int virq,
 		} else {
 			index = -ENOMEM;
 		}
-	} else {
+	} else if (info->type == X86_IRQ_ALLOC_TYPE_MSI ||
+		   info->type == X86_IRQ_ALLOC_TYPE_MSIX) {
 		bool align = (info->type == X86_IRQ_ALLOC_TYPE_MSI);
 
-		index = alloc_irq_index(devid, nr_irqs, align);
+		index = alloc_irq_index(devid, nr_irqs, align, info->msi_dev);
+	} else {
+		index = alloc_irq_index(devid, nr_irqs, false, NULL);
 	}
+
 	if (index < 0) {
 		pr_warn("Failed to allocate IRTE\n");
 		ret = index;
-- 
2.20.1

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

  parent reply index

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-08 22:18 [PATCH 0/3] AMD IOMMU Changes for NTB Logan Gunthorpe
2019-10-08 22:18 ` [PATCH 1/3] iommu/amd: Implement dma_[un]map_resource() Logan Gunthorpe
2019-10-09  6:57   ` Christoph Hellwig
2019-10-09 16:17     ` Logan Gunthorpe
2019-10-09 16:17       ` Logan Gunthorpe
2019-10-08 22:18 ` [PATCH 2/3] iommu/amd: Support multiple PCI DMA aliases in device table Logan Gunthorpe
2019-10-08 22:18 ` Logan Gunthorpe [this message]
2019-10-15 13:37   ` [PATCH 3/3] iommu/amd: Support multiple PCI DMA aliases in IRQ Remapping Joerg Roedel
2019-10-15 16:16     ` Logan Gunthorpe

Reply instructions:

You may reply publically 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=20191008221837.13067-4-logang@deltatee.com \
    --to=logang@deltatee.com \
    --cc=iommu@lists.linux-foundation.org \
    --cc=joro@8bytes.org \
    --cc=kchow@gigaio.com \
    --cc=linux-kernel@vger.kernel.org \
    /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

IOMMU Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-iommu/0 linux-iommu/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-iommu linux-iommu/ https://lore.kernel.org/linux-iommu \
		iommu@lists.linux-foundation.org
	public-inbox-index linux-iommu

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.linux-foundation.lists.iommu


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git