This patch introduced the API to return device properties about a PLATFORM device (if described by a device tree or ACPI) and the skeleton of the implementation for VFIO_PLATFORM. Information about any device node bound by VFIO_PLATFORM should be queried via the introduced ioctl VFIO_DEVICE_GET_DEV_PROPERTY.
The user needs to know the name and the data type of the property he is accessing. Signed-off-by: Antonios Motakis <[email protected]> --- drivers/vfio/platform/Makefile | 3 +- drivers/vfio/platform/properties.c | 61 +++++++++++++++++++++++++++ drivers/vfio/platform/vfio_platform_common.c | 35 +++++++++++++++ drivers/vfio/platform/vfio_platform_private.h | 7 +++ include/uapi/linux/vfio.h | 26 ++++++++++++ 5 files changed, 131 insertions(+), 1 deletion(-) create mode 100644 drivers/vfio/platform/properties.c diff --git a/drivers/vfio/platform/Makefile b/drivers/vfio/platform/Makefile index 81de144..99f3ba1 100644 --- a/drivers/vfio/platform/Makefile +++ b/drivers/vfio/platform/Makefile @@ -1,5 +1,6 @@ -vfio-platform-y := vfio_platform.o vfio_platform_common.o vfio_platform_irq.o +vfio-platform-y := vfio_platform.o vfio_platform_common.o vfio_platform_irq.o \ + devtree.o obj-$(CONFIG_VFIO_PLATFORM) += vfio-platform.o diff --git a/drivers/vfio/platform/properties.c b/drivers/vfio/platform/properties.c new file mode 100644 index 0000000..8b90465 --- /dev/null +++ b/drivers/vfio/platform/properties.c @@ -0,0 +1,61 @@ +#include <linux/slab.h> +#include <linux/vfio.h> +#include <linux/property.h> +#include "vfio_platform_private.h" + +static int dev_property_get_strings(struct device *dev, + char *name, unsigned *lenp, + void __user *datap, unsigned long datasz) +{ + return -EINVAL; +} + +static int dev_property_get_uint(struct device *dev, char *name, + uint32_t type, unsigned *lenp, + void __user *datap, unsigned long datasz) +{ + return -EINVAL; +} + +int vfio_platform_dev_properties(struct device *dev, + uint32_t type, unsigned *lenp, + void __user *datap, unsigned long datasz) +{ + char *name; + long namesz; + int ret; + + namesz = strnlen_user(datap, datasz); + if (!namesz) + return -EFAULT; + if (namesz > datasz) + return -EINVAL; + + name = kzalloc(namesz, GFP_KERNEL); + if (!name) + return -ENOMEM; + if (strncpy_from_user(name, datap, namesz) <= 0) { + kfree(name); + return -EFAULT; + } + + switch (type) { + case VFIO_DEV_PROPERTY_TYPE_STRINGS: + ret = dev_property_get_strings(dev, name, lenp, datap, datasz); + break; + + case VFIO_DEV_PROPERTY_TYPE_U64: + case VFIO_DEV_PROPERTY_TYPE_U32: + case VFIO_DEV_PROPERTY_TYPE_U16: + case VFIO_DEV_PROPERTY_TYPE_U8: + ret = dev_property_get_uint(dev, name, type, lenp, + datap, datasz); + break; + + default: + ret = -EINVAL; + } + + kfree(name); + return ret; +} diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c index a532a25..83ad4b74 100644 --- a/drivers/vfio/platform/vfio_platform_common.c +++ b/drivers/vfio/platform/vfio_platform_common.c @@ -19,6 +19,7 @@ #include <linux/slab.h> #include <linux/types.h> #include <linux/vfio.h> +#include <linux/property.h> #include "vfio_platform_private.h" @@ -251,6 +252,34 @@ static long vfio_platform_ioctl(void *device_data, return ret; + } else if (cmd == VFIO_DEVICE_GET_DEV_PROPERTY) { + struct vfio_dev_property info; + void __user *datap; + unsigned long datasz; + int ret; + + if (!vdev->dev) + return -EINVAL; + + minsz = offsetofend(struct vfio_dev_property, length); + + if (copy_from_user(&info, (void __user *)arg, minsz)) + return -EFAULT; + + if (info.argsz < minsz) + return -EINVAL; + + datap = (void __user *) arg + minsz; + datasz = info.argsz - minsz; + + ret = vfio_platform_dev_properties(vdev->dev, info.type, + &info.length, datap, datasz); + + if (copy_to_user((void __user *)arg, &info, minsz)) + ret = -EFAULT; + + return ret; + } else if (cmd == VFIO_DEVICE_RESET) return -EINVAL; @@ -501,6 +530,12 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev, return ret; } + /* add device properties flag */ + if (device_property_present(dev, "name")) { + vdev->dev = dev; + vdev->flags |= VFIO_DEVICE_FLAGS_DEV_PROPERTIES; + } + mutex_init(&vdev->igate); return 0; diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h index c3d5b4b..fc6b1fb 100644 --- a/drivers/vfio/platform/vfio_platform_private.h +++ b/drivers/vfio/platform/vfio_platform_private.h @@ -53,6 +53,7 @@ struct vfio_platform_device { u32 num_irqs; int refcnt; struct mutex igate; + struct device *dev; /* * These fields should be filled by the bus specific binder @@ -79,4 +80,10 @@ extern int vfio_platform_set_irqs_ioctl(struct vfio_platform_device *vdev, unsigned start, unsigned count, void *data); +/* device properties support in devtree.c */ +extern int vfio_platform_dev_properties(struct device *dev, + uint32_t type, unsigned *lenp, + void __user *datap, + unsigned long datasz); + #endif /* VFIO_PLATFORM_PRIVATE_H */ diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index 544d3d8..ac50ab3f 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -161,12 +161,38 @@ struct vfio_device_info { #define VFIO_DEVICE_FLAGS_PCI (1 << 1) /* vfio-pci device */ #define VFIO_DEVICE_FLAGS_PLATFORM (1 << 2) /* vfio-platform device */ #define VFIO_DEVICE_FLAGS_AMBA (1 << 3) /* vfio-amba device */ +#define VFIO_DEVICE_FLAGS_DEV_PROPERTIES (1 << 4) /* Device properties */ __u32 num_regions; /* Max region index + 1 */ __u32 num_irqs; /* Max IRQ index + 1 */ }; #define VFIO_DEVICE_GET_INFO _IO(VFIO_TYPE, VFIO_BASE + 7) /** + * VFIO_DEVICE_GET_DEV_PROPERTY - _IOR(VFIO_TYPE, VFIO_BASE + 16, + * struct vfio_devtree_info) + * + * Retrive a device property, e.g. from a device tree if available. + * Caller will initialize data[] with a single string with the requested + * devicetree property name, and type depending on whether a array of strings + * or an array of u32 values is expected. On success, data[] will be extended + * with the requested information, either as an array of u32, or with a list + * of strings sepparated by the NULL terminating character. + * Return: 0 on success, -errno on failure. + */ +struct vfio_dev_property { + __u32 argsz; + __u32 type; +#define VFIO_DEV_PROPERTY_TYPE_STRINGS 0 +#define VFIO_DEV_PROPERTY_TYPE_U8 1 +#define VFIO_DEV_PROPERTY_TYPE_U16 2 +#define VFIO_DEV_PROPERTY_TYPE_U32 3 +#define VFIO_DEV_PROPERTY_TYPE_U64 4 + __u32 length; + __u8 data[]; +}; +#define VFIO_DEVICE_GET_DEV_PROPERTY _IO(VFIO_TYPE, VFIO_BASE + 17) + +/** * VFIO_DEVICE_GET_REGION_INFO - _IOWR(VFIO_TYPE, VFIO_BASE + 8, * struct vfio_region_info) * -- 2.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
