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authorLinus Torvalds <torvalds@linux-foundation.org>2015-06-28 12:32:13 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-06-28 12:32:13 -0700
commitb779157dd3db6199b50e7ad64678a1ceedbeebcf (patch)
treed00314f158869d072849f4635f70b80680a04638 /drivers/vfio
parent4a10a91756ef381bced7b88cfb9232f660b92d93 (diff)
parenta714ea5fa41623c8d8c42bed0dfb38a4d653451d (diff)
Merge tag 'vfio-v4.2-rc1' of git://github.com/awilliam/linux-vfio
Pull VFIO updates from Alex Williamson: - fix race with device reference versus driver release (Alex Williamson) - add reset hooks and Calxeda xgmac reset for vfio-platform (Eric Auger) - enable vfio-platform for ARM64 (Eric Auger) - tag Baptiste Reynal as vfio-platform sub-maintainer (Alex Williamson) * tag 'vfio-v4.2-rc1' of git://github.com/awilliam/linux-vfio: MAINTAINERS: Add vfio-platform sub-maintainer VFIO: platform: enable ARM64 build VFIO: platform: Calxeda xgmac reset module VFIO: platform: populate the reset function on probe VFIO: platform: add reset callback VFIO: platform: add reset struct and lookup table vfio/pci: Fix racy vfio_device_get_from_dev() call
Diffstat (limited to 'drivers/vfio')
-rw-r--r--drivers/vfio/pci/vfio_pci.c16
-rw-r--r--drivers/vfio/platform/Kconfig4
-rw-r--r--drivers/vfio/platform/Makefile2
-rw-r--r--drivers/vfio/platform/reset/Kconfig7
-rw-r--r--drivers/vfio/platform/reset/Makefile5
-rw-r--r--drivers/vfio/platform/reset/vfio_platform_calxedaxgmac.c86
-rw-r--r--drivers/vfio/platform/vfio_platform_common.c60
-rw-r--r--drivers/vfio/platform/vfio_platform_private.h7
-rw-r--r--drivers/vfio/vfio.c27
9 files changed, 195 insertions, 19 deletions
diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index e9851add6f4e..964ad572aaee 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -1056,19 +1056,21 @@ struct vfio_devices {
static int vfio_pci_get_devs(struct pci_dev *pdev, void *data)
{
struct vfio_devices *devs = data;
- struct pci_driver *pci_drv = ACCESS_ONCE(pdev->driver);
-
- if (pci_drv != &vfio_pci_driver)
- return -EBUSY;
+ struct vfio_device *device;
if (devs->cur_index == devs->max_index)
return -ENOSPC;
- devs->devices[devs->cur_index] = vfio_device_get_from_dev(&pdev->dev);
- if (!devs->devices[devs->cur_index])
+ device = vfio_device_get_from_dev(&pdev->dev);
+ if (!device)
return -EINVAL;
- devs->cur_index++;
+ if (pci_dev_driver(pdev) != &vfio_pci_driver) {
+ vfio_device_put(device);
+ return -EBUSY;
+ }
+
+ devs->devices[devs->cur_index++] = device;
return 0;
}
diff --git a/drivers/vfio/platform/Kconfig b/drivers/vfio/platform/Kconfig
index 9a4403e2a36c..bb30128782aa 100644
--- a/drivers/vfio/platform/Kconfig
+++ b/drivers/vfio/platform/Kconfig
@@ -1,6 +1,6 @@
config VFIO_PLATFORM
tristate "VFIO support for platform devices"
- depends on VFIO && EVENTFD && ARM
+ depends on VFIO && EVENTFD && (ARM || ARM64)
select VFIO_VIRQFD
help
Support for platform devices with VFIO. This is required to make
@@ -18,3 +18,5 @@ config VFIO_AMBA
framework.
If you don't know what to do here, say N.
+
+source "drivers/vfio/platform/reset/Kconfig"
diff --git a/drivers/vfio/platform/Makefile b/drivers/vfio/platform/Makefile
index 81de144c0eaa..9ce8afe28450 100644
--- a/drivers/vfio/platform/Makefile
+++ b/drivers/vfio/platform/Makefile
@@ -2,7 +2,9 @@
vfio-platform-y := vfio_platform.o vfio_platform_common.o vfio_platform_irq.o
obj-$(CONFIG_VFIO_PLATFORM) += vfio-platform.o
+obj-$(CONFIG_VFIO_PLATFORM) += reset/
vfio-amba-y := vfio_amba.o
obj-$(CONFIG_VFIO_AMBA) += vfio-amba.o
+obj-$(CONFIG_VFIO_AMBA) += reset/
diff --git a/drivers/vfio/platform/reset/Kconfig b/drivers/vfio/platform/reset/Kconfig
new file mode 100644
index 000000000000..746b96b0003b
--- /dev/null
+++ b/drivers/vfio/platform/reset/Kconfig
@@ -0,0 +1,7 @@
+config VFIO_PLATFORM_CALXEDAXGMAC_RESET
+ tristate "VFIO support for calxeda xgmac reset"
+ depends on VFIO_PLATFORM
+ help
+ Enables the VFIO platform driver to handle reset for Calxeda xgmac
+
+ If you don't know what to do here, say N.
diff --git a/drivers/vfio/platform/reset/Makefile b/drivers/vfio/platform/reset/Makefile
new file mode 100644
index 000000000000..2a486af9f8fa
--- /dev/null
+++ b/drivers/vfio/platform/reset/Makefile
@@ -0,0 +1,5 @@
+vfio-platform-calxedaxgmac-y := vfio_platform_calxedaxgmac.o
+
+ccflags-y += -Idrivers/vfio/platform
+
+obj-$(CONFIG_VFIO_PLATFORM_CALXEDAXGMAC_RESET) += vfio-platform-calxedaxgmac.o
diff --git a/drivers/vfio/platform/reset/vfio_platform_calxedaxgmac.c b/drivers/vfio/platform/reset/vfio_platform_calxedaxgmac.c
new file mode 100644
index 000000000000..619dc7d22082
--- /dev/null
+++ b/drivers/vfio/platform/reset/vfio_platform_calxedaxgmac.c
@@ -0,0 +1,86 @@
+/*
+ * VFIO platform driver specialized for Calxeda xgmac reset
+ * reset code is inherited from calxeda xgmac native driver
+ *
+ * Copyright 2010-2011 Calxeda, Inc.
+ * Copyright (c) 2015 Linaro Ltd.
+ * www.linaro.org
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+
+#include "vfio_platform_private.h"
+
+#define DRIVER_VERSION "0.1"
+#define DRIVER_AUTHOR "Eric Auger <eric.auger@linaro.org>"
+#define DRIVER_DESC "Reset support for Calxeda xgmac vfio platform device"
+
+#define CALXEDAXGMAC_COMPAT "calxeda,hb-xgmac"
+
+/* XGMAC Register definitions */
+#define XGMAC_CONTROL 0x00000000 /* MAC Configuration */
+
+/* DMA Control and Status Registers */
+#define XGMAC_DMA_CONTROL 0x00000f18 /* Ctrl (Operational Mode) */
+#define XGMAC_DMA_INTR_ENA 0x00000f1c /* Interrupt Enable */
+
+/* DMA Control registe defines */
+#define DMA_CONTROL_ST 0x00002000 /* Start/Stop Transmission */
+#define DMA_CONTROL_SR 0x00000002 /* Start/Stop Receive */
+
+/* Common MAC defines */
+#define MAC_ENABLE_TX 0x00000008 /* Transmitter Enable */
+#define MAC_ENABLE_RX 0x00000004 /* Receiver Enable */
+
+static inline void xgmac_mac_disable(void __iomem *ioaddr)
+{
+ u32 value = readl(ioaddr + XGMAC_DMA_CONTROL);
+
+ value &= ~(DMA_CONTROL_ST | DMA_CONTROL_SR);
+ writel(value, ioaddr + XGMAC_DMA_CONTROL);
+
+ value = readl(ioaddr + XGMAC_CONTROL);
+ value &= ~(MAC_ENABLE_TX | MAC_ENABLE_RX);
+ writel(value, ioaddr + XGMAC_CONTROL);
+}
+
+int vfio_platform_calxedaxgmac_reset(struct vfio_platform_device *vdev)
+{
+ struct vfio_platform_region reg = vdev->regions[0];
+
+ if (!reg.ioaddr) {
+ reg.ioaddr =
+ ioremap_nocache(reg.addr, reg.size);
+ if (!reg.ioaddr)
+ return -ENOMEM;
+ }
+
+ /* disable IRQ */
+ writel(0, reg.ioaddr + XGMAC_DMA_INTR_ENA);
+
+ /* Disable the MAC core */
+ xgmac_mac_disable(reg.ioaddr);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(vfio_platform_calxedaxgmac_reset);
+
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
index abcff7a1aa66..e43efb5e92bf 100644
--- a/drivers/vfio/platform/vfio_platform_common.c
+++ b/drivers/vfio/platform/vfio_platform_common.c
@@ -25,6 +25,44 @@
static DEFINE_MUTEX(driver_lock);
+static const struct vfio_platform_reset_combo reset_lookup_table[] = {
+ {
+ .compat = "calxeda,hb-xgmac",
+ .reset_function_name = "vfio_platform_calxedaxgmac_reset",
+ .module_name = "vfio-platform-calxedaxgmac",
+ },
+};
+
+static void vfio_platform_get_reset(struct vfio_platform_device *vdev,
+ struct device *dev)
+{
+ const char *compat;
+ int (*reset)(struct vfio_platform_device *);
+ int ret, i;
+
+ ret = device_property_read_string(dev, "compatible", &compat);
+ if (ret)
+ return;
+
+ for (i = 0 ; i < ARRAY_SIZE(reset_lookup_table); i++) {
+ if (!strcmp(reset_lookup_table[i].compat, compat)) {
+ request_module(reset_lookup_table[i].module_name);
+ reset = __symbol_get(
+ reset_lookup_table[i].reset_function_name);
+ if (reset) {
+ vdev->reset = reset;
+ return;
+ }
+ }
+ }
+}
+
+static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
+{
+ if (vdev->reset)
+ symbol_put_addr(vdev->reset);
+}
+
static int vfio_platform_regions_init(struct vfio_platform_device *vdev)
{
int cnt = 0, i;
@@ -100,6 +138,8 @@ static void vfio_platform_release(void *device_data)
mutex_lock(&driver_lock);
if (!(--vdev->refcnt)) {
+ if (vdev->reset)
+ vdev->reset(vdev);
vfio_platform_regions_cleanup(vdev);
vfio_platform_irq_cleanup(vdev);
}
@@ -127,6 +167,9 @@ static int vfio_platform_open(void *device_data)
ret = vfio_platform_irq_init(vdev);
if (ret)
goto err_irq;
+
+ if (vdev->reset)
+ vdev->reset(vdev);
}
vdev->refcnt++;
@@ -159,6 +202,8 @@ static long vfio_platform_ioctl(void *device_data,
if (info.argsz < minsz)
return -EINVAL;
+ if (vdev->reset)
+ vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
info.flags = vdev->flags;
info.num_regions = vdev->num_regions;
info.num_irqs = vdev->num_irqs;
@@ -252,8 +297,12 @@ static long vfio_platform_ioctl(void *device_data,
return ret;
- } else if (cmd == VFIO_DEVICE_RESET)
- return -EINVAL;
+ } else if (cmd == VFIO_DEVICE_RESET) {
+ if (vdev->reset)
+ return vdev->reset(vdev);
+ else
+ return -EINVAL;
+ }
return -ENOTTY;
}
@@ -502,6 +551,8 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev,
return ret;
}
+ vfio_platform_get_reset(vdev, dev);
+
mutex_init(&vdev->igate);
return 0;
@@ -513,8 +564,11 @@ struct vfio_platform_device *vfio_platform_remove_common(struct device *dev)
struct vfio_platform_device *vdev;
vdev = vfio_del_group_dev(dev);
- if (vdev)
+
+ if (vdev) {
+ vfio_platform_put_reset(vdev);
iommu_group_put(dev->iommu_group);
+ }
return vdev;
}
diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h
index 5d31e0473406..1c9b3d59543c 100644
--- a/drivers/vfio/platform/vfio_platform_private.h
+++ b/drivers/vfio/platform/vfio_platform_private.h
@@ -67,6 +67,13 @@ struct vfio_platform_device {
struct resource*
(*get_resource)(struct vfio_platform_device *vdev, int i);
int (*get_irq)(struct vfio_platform_device *vdev, int i);
+ int (*reset)(struct vfio_platform_device *vdev);
+};
+
+struct vfio_platform_reset_combo {
+ const char *compat;
+ const char *reset_function_name;
+ const char *module_name;
};
extern int vfio_platform_probe_common(struct vfio_platform_device *vdev,
diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c
index e1278fe04b1e..2fb29dfeffbd 100644
--- a/drivers/vfio/vfio.c
+++ b/drivers/vfio/vfio.c
@@ -661,18 +661,29 @@ int vfio_add_group_dev(struct device *dev,
EXPORT_SYMBOL_GPL(vfio_add_group_dev);
/**
- * Get a reference to the vfio_device for a device that is known to
- * be bound to a vfio driver. The driver implicitly holds a
- * vfio_device reference between vfio_add_group_dev and
- * vfio_del_group_dev. We can therefore use drvdata to increment
- * that reference from the struct device. This additional
- * reference must be released by calling vfio_device_put.
+ * Get a reference to the vfio_device for a device. Even if the
+ * caller thinks they own the device, they could be racing with a
+ * release call path, so we can't trust drvdata for the shortcut.
+ * Go the long way around, from the iommu_group to the vfio_group
+ * to the vfio_device.
*/
struct vfio_device *vfio_device_get_from_dev(struct device *dev)
{
- struct vfio_device *device = dev_get_drvdata(dev);
+ struct iommu_group *iommu_group;
+ struct vfio_group *group;
+ struct vfio_device *device;
+
+ iommu_group = iommu_group_get(dev);
+ if (!iommu_group)
+ return NULL;
- vfio_device_get(device);
+ group = vfio_group_get_from_iommu(iommu_group);
+ iommu_group_put(iommu_group);
+ if (!group)
+ return NULL;
+
+ device = vfio_group_get_device(group, dev);
+ vfio_group_put(group);
return device;
}