From e8909e67cac3ad3868dc86cc6b1445f39c71bf63 Mon Sep 17 00:00:00 2001 From: Antonios Motakis Date: Mon, 16 Mar 2015 14:08:46 -0600 Subject: [PATCH] vfio/platform: return info for device memory mapped IO regions This patch enables the IOCTLs VFIO_DEVICE_GET_REGION_INFO ioctl call, which allows the user to learn about the available MMIO resources of a device. Signed-off-by: Antonios Motakis Signed-off-by: Baptiste Reynal Reviewed-by: Eric Auger Tested-by: Eric Auger Signed-off-by: Alex Williamson --- drivers/vfio/platform/vfio_platform_common.c | 106 +++++++++++++++++- drivers/vfio/platform/vfio_platform_private.h | 22 ++++ 2 files changed, 124 insertions(+), 4 deletions(-) diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c index c2f853a3b3dd..47f6309b4889 100644 --- a/drivers/vfio/platform/vfio_platform_common.c +++ b/drivers/vfio/platform/vfio_platform_common.c @@ -23,17 +23,97 @@ #include "vfio_platform_private.h" +static DEFINE_MUTEX(driver_lock); + +static int vfio_platform_regions_init(struct vfio_platform_device *vdev) +{ + int cnt = 0, i; + + while (vdev->get_resource(vdev, cnt)) + cnt++; + + vdev->regions = kcalloc(cnt, sizeof(struct vfio_platform_region), + GFP_KERNEL); + if (!vdev->regions) + return -ENOMEM; + + for (i = 0; i < cnt; i++) { + struct resource *res = + vdev->get_resource(vdev, i); + + if (!res) + goto err; + + vdev->regions[i].addr = res->start; + vdev->regions[i].size = resource_size(res); + vdev->regions[i].flags = 0; + + switch (resource_type(res)) { + case IORESOURCE_MEM: + vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_MMIO; + break; + case IORESOURCE_IO: + vdev->regions[i].type = VFIO_PLATFORM_REGION_TYPE_PIO; + break; + default: + goto err; + } + } + + vdev->num_regions = cnt; + + return 0; +err: + kfree(vdev->regions); + return -EINVAL; +} + +static void vfio_platform_regions_cleanup(struct vfio_platform_device *vdev) +{ + vdev->num_regions = 0; + kfree(vdev->regions); +} + static void vfio_platform_release(void *device_data) { + struct vfio_platform_device *vdev = device_data; + + mutex_lock(&driver_lock); + + if (!(--vdev->refcnt)) { + vfio_platform_regions_cleanup(vdev); + } + + mutex_unlock(&driver_lock); + module_put(THIS_MODULE); } static int vfio_platform_open(void *device_data) { + struct vfio_platform_device *vdev = device_data; + int ret; + if (!try_module_get(THIS_MODULE)) return -ENODEV; + mutex_lock(&driver_lock); + + if (!vdev->refcnt) { + ret = vfio_platform_regions_init(vdev); + if (ret) + goto err_reg; + } + + vdev->refcnt++; + + mutex_unlock(&driver_lock); return 0; + +err_reg: + mutex_unlock(&driver_lock); + module_put(THIS_MODULE); + return ret; } static long vfio_platform_ioctl(void *device_data, @@ -54,15 +134,33 @@ static long vfio_platform_ioctl(void *device_data, return -EINVAL; info.flags = vdev->flags; - info.num_regions = 0; + info.num_regions = vdev->num_regions; info.num_irqs = 0; return copy_to_user((void __user *)arg, &info, minsz); - } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) - return -EINVAL; + } else if (cmd == VFIO_DEVICE_GET_REGION_INFO) { + struct vfio_region_info info; + + minsz = offsetofend(struct vfio_region_info, offset); + + if (copy_from_user(&info, (void __user *)arg, minsz)) + return -EFAULT; + + if (info.argsz < minsz) + return -EINVAL; + + if (info.index >= vdev->num_regions) + return -EINVAL; + + /* map offset to the physical address */ + info.offset = VFIO_PLATFORM_INDEX_TO_OFFSET(info.index); + info.size = vdev->regions[info.index].size; + info.flags = vdev->regions[info.index].flags; + + return copy_to_user((void __user *)arg, &info, minsz); - else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) + } else if (cmd == VFIO_DEVICE_GET_IRQ_INFO) return -EINVAL; else if (cmd == VFIO_DEVICE_SET_IRQS) diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h index c04698872440..3551f6d97fc3 100644 --- a/drivers/vfio/platform/vfio_platform_private.h +++ b/drivers/vfio/platform/vfio_platform_private.h @@ -18,7 +18,29 @@ #include #include +#define VFIO_PLATFORM_OFFSET_SHIFT 40 +#define VFIO_PLATFORM_OFFSET_MASK (((u64)(1) << VFIO_PLATFORM_OFFSET_SHIFT) - 1) + +#define VFIO_PLATFORM_OFFSET_TO_INDEX(off) \ + (off >> VFIO_PLATFORM_OFFSET_SHIFT) + +#define VFIO_PLATFORM_INDEX_TO_OFFSET(index) \ + ((u64)(index) << VFIO_PLATFORM_OFFSET_SHIFT) + +struct vfio_platform_region { + u64 addr; + resource_size_t size; + u32 flags; + u32 type; +#define VFIO_PLATFORM_REGION_TYPE_MMIO 1 +#define VFIO_PLATFORM_REGION_TYPE_PIO 2 +}; + struct vfio_platform_device { + struct vfio_platform_region *regions; + u32 num_regions; + int refcnt; + /* * These fields should be filled by the bus specific binder */ -- 2.20.1