Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1346859

[RFC v5 04/17] dma-reserved-iommu: alloc/free_reserved_iova_domain

From Eric Auger <eric.auger@linaro.org>
Newsgroups linux.kernel
Subject [RFC v5 04/17] dma-reserved-iommu: alloc/free_reserved_iova_domain
Date 2016-03-01 19:30 +0100
Message-ID <r7Xdy-4kR-61@gated-at.bofh.it> (permalink)
References <r7Xdw-4kR-7@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw

Introduce alloc/free_reserved_iova_domain in the IOMMU API.
alloc_reserved_iova_domain initializes an iova domain at a given
iova base address and with a given size. This iova domain will
be used to allocate iova within that window. Those IOVAs will be reserved
for special purpose, typically MSI frame binding. Allocation function
within the reserved iova domain will be introduced in subsequent patches.

Those functions are implemented and exposed if CONFIG_IOMMU_DMA_RESERVED
is seta.

Signed-off-by: Eric Auger <eric.auger@linaro.org>

---

v3 -> v4:
- formerly in "iommu/arm-smmu: implement alloc/free_reserved_iova_domain" &
  "iommu: add alloc/free_reserved_iova_domain"

v2 -> v3:
- remove iommu_alloc_reserved_iova_domain & iommu_free_reserved_iova_domain
  static implementation in case CONFIG_IOMMU_API is not set

v1 -> v2:
- moved from vfio API to IOMMU API
---
 drivers/iommu/Kconfig              |  8 +++++
 drivers/iommu/Makefile             |  1 +
 drivers/iommu/dma-reserved-iommu.c | 74 ++++++++++++++++++++++++++++++++++++++
 include/linux/dma-reserved-iommu.h | 45 +++++++++++++++++++++++
 4 files changed, 128 insertions(+)
 create mode 100644 drivers/iommu/dma-reserved-iommu.c
 create mode 100644 include/linux/dma-reserved-iommu.h

diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index a1e75cb..0775143 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -55,6 +55,12 @@ config IOMMU_DMA
 	select IOMMU_API
 	select IOMMU_IOVA
 
+# IOMMU reserved IOVA mapping (MSI doorbell)
+config IOMMU_DMA_RESERVED
+	bool
+	select IOMMU_API
+	select IOMMU_IOVA
+
 config FSL_PAMU
 	bool "Freescale IOMMU support"
 	depends on PPC32
@@ -288,6 +294,7 @@ config SPAPR_TCE_IOMMU
 config ARM_SMMU
 	bool "ARM Ltd. System MMU (SMMU) Support"
 	depends on (ARM64 || ARM) && MMU
+	select IOMMU_DMA_RESERVED
 	select IOMMU_API
 	select IOMMU_IO_PGTABLE_LPAE
 	select ARM_DMA_USE_IOMMU if ARM
@@ -301,6 +308,7 @@ config ARM_SMMU
 config ARM_SMMU_V3
 	bool "ARM Ltd. System MMU Version 3 (SMMUv3) Support"
 	depends on ARM64 && PCI
+	select IOMMU_DMA_RESERVED
 	select IOMMU_API
 	select IOMMU_IO_PGTABLE_LPAE
 	select GENERIC_MSI_IRQ_DOMAIN
diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
index 42fc0c2..ea68d23 100644
--- a/drivers/iommu/Makefile
+++ b/drivers/iommu/Makefile
@@ -2,6 +2,7 @@ obj-$(CONFIG_IOMMU_API) += iommu.o
 obj-$(CONFIG_IOMMU_API) += iommu-traces.o
 obj-$(CONFIG_IOMMU_API) += iommu-sysfs.o
 obj-$(CONFIG_IOMMU_DMA) += dma-iommu.o
+obj-$(CONFIG_IOMMU_DMA_RESERVED) += dma-reserved-iommu.o
 obj-$(CONFIG_IOMMU_IO_PGTABLE) += io-pgtable.o
 obj-$(CONFIG_IOMMU_IO_PGTABLE_LPAE) += io-pgtable-arm.o
 obj-$(CONFIG_IOMMU_IOVA) += iova.o
diff --git a/drivers/iommu/dma-reserved-iommu.c b/drivers/iommu/dma-reserved-iommu.c
new file mode 100644
index 0000000..41a1add
--- /dev/null
+++ b/drivers/iommu/dma-reserved-iommu.c
@@ -0,0 +1,74 @@
+/*
+ * Reserved IOVA Management
+ *
+ * Copyright (c) 2015 Linaro Ltd.
+ *              www.linaro.org
+ *
+ * Copyright (C) 2000-2004 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/iommu.h>
+#include <linux/iova.h>
+
+int iommu_alloc_reserved_iova_domain(struct iommu_domain *domain,
+				     dma_addr_t iova, size_t size,
+				     unsigned long order)
+{
+	unsigned long granule, mask;
+	struct iova_domain *iovad;
+	int ret = 0;
+
+	granule = 1UL << order;
+	mask = granule - 1;
+	if (iova & mask || (!size) || (size & mask))
+		return -EINVAL;
+
+	mutex_lock(&domain->reserved_mutex);
+
+	if (domain->reserved_iova_cookie) {
+		ret = -EEXIST;
+		goto unlock;
+	}
+
+	iovad = kzalloc(sizeof(struct iova_domain), GFP_KERNEL);
+	if (!iovad) {
+		ret = -ENOMEM;
+		goto unlock;
+	}
+
+	init_iova_domain(iovad, granule,
+			 iova >> order, (iova + size - 1) >> order);
+	domain->reserved_iova_cookie = iovad;
+
+unlock:
+	mutex_unlock(&domain->reserved_mutex);
+	return ret;
+}
+EXPORT_SYMBOL_GPL(iommu_alloc_reserved_iova_domain);
+
+void iommu_free_reserved_iova_domain(struct iommu_domain *domain)
+{
+	struct iova_domain *iovad =
+		(struct iova_domain *)domain->reserved_iova_cookie;
+
+	if (!iovad)
+		return;
+
+	mutex_lock(&domain->reserved_mutex);
+
+	put_iova_domain(iovad);
+	kfree(iovad);
+
+	mutex_unlock(&domain->reserved_mutex);
+}
+EXPORT_SYMBOL_GPL(iommu_free_reserved_iova_domain);
diff --git a/include/linux/dma-reserved-iommu.h b/include/linux/dma-reserved-iommu.h
new file mode 100644
index 0000000..5bf863b
--- /dev/null
+++ b/include/linux/dma-reserved-iommu.h
@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) 2015 Linaro Ltd.
+ *              www.linaro.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+#ifndef __DMA_RESERVED_IOMMU_H
+#define __DMA_RESERVED_IOMMU_H
+
+#ifdef __KERNEL__
+#include <asm/errno.h>
+
+#ifdef CONFIG_IOMMU_DMA_RESERVED
+#include <linux/iommu.h>
+
+/**
+ * iommu_alloc_reserved_iova_domain: allocate the reserved iova domain
+ *
+ * @domain: iommu domain handle
+ * @iova: base iova address
+ * @size: iova window size
+ * @order: page order
+ */
+int iommu_alloc_reserved_iova_domain(struct iommu_domain *domain,
+				     dma_addr_t iova, size_t size,
+				     unsigned long order);
+
+/**
+ * iommu_free_reserved_iova_domain: free the reserved iova domain
+ *
+ * @domain: iommu domain handle
+ */
+void iommu_free_reserved_iova_domain(struct iommu_domain *domain);
+
+#endif	/* CONFIG_IOMMU_DMA_RESERVED */
+#endif	/* __KERNEL__ */
+#endif	/* __DMA_RESERVED_IOMMU_H */
-- 
1.9.1

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[RFC v5 00/17] KVM PCIe/MSI passthrough on ARM/ARM64 Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:30 +0100
  [RFC v5 07/17] dma-reserved-iommu: iommu_unmap_reserved Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:30 +0100
  [RFC v5 02/17] iommu/arm-smmu: advertise DOMAIN_ATTR_MSI_MAPPING attribute Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:30 +0100
  [RFC v5 17/17] vfio/type1: return MSI mapping requirements with VFIO_IOMMU_GET_INFO Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:30 +0100
  [RFC v5 16/17] iommu/arm-smmu: do not advertise IOMMU_CAP_INTR_REMAP Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:30 +0100
  [RFC v5 14/17] vfio: allow the user to register reserved iova range for MSI mapping Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:30 +0100
  [RFC v5 01/17] iommu: Add DOMAIN_ATTR_MSI_MAPPING attribute Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:30 +0100
  [RFC v5 10/17] msi: export msi_get_domain_info Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:30 +0100
  [RFC v5 09/17] irqchip/gic-v3-its: ITS advertises MSI_FLAG_IRQ_REMAPPING Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:30 +0100
  [RFC v5 08/17] msi: Add a new MSI_FLAG_IRQ_REMAPPING flag Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:30 +0100
  [RFC v5 12/17] msi: IOMMU map the doorbell address when needed Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:30 +0100
  [RFC v5 04/17] dma-reserved-iommu: alloc/free_reserved_iova_domain Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:30 +0100
  [RFC v5 13/17] vfio: introduce VFIO_IOVA_RESERVED vfio_dma type Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:40 +0100
  [RFC v5 11/17] msi: msi_compose wrapper Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:40 +0100
  [RFC v5 15/17] vfio/type1: also check IRQ remapping capability at msi domain Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:40 +0100
  [RFC v5 05/17] dma-reserved-iommu: reserved binding rb-tree and helpers Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:40 +0100
  [RFC v5 06/17] dma-reserved-iommu: iommu_get/put_single_reserved Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:40 +0100
  [RFC v5 03/17] iommu: introduce a reserved iova cookie Eric Auger <eric.auger@linaro.org> - 2016-03-01 19:40 +0100
    Re: [RFC v5 03/17] iommu: introduce a reserved iova cookie Julien Grall <julien.grall@arm.com> - 2016-03-03 17:30 +0100
  Re: [RFC v5 00/17] KVM PCIe/MSI passthrough on ARM/ARM64 "Jaggi, Manish" <Manish.Jaggi@caviumnetworks.com> - 2016-03-02 10:50 +0100
    Re: [RFC v5 00/17] KVM PCIe/MSI passthrough on ARM/ARM64 Eric Auger <eric.auger@linaro.org> - 2016-03-02 13:40 +0100

csiph-web