From 120e214e504fd6d3e33ec4b661193600b2faab95 Mon Sep 17 00:00:00 2001 From: Dong Jia Shi Date: Fri, 17 Mar 2017 04:17:38 +0100 Subject: [PATCH] vfio: ccw: realize VFIO_DEVICE_G(S)ET_IRQ_INFO ioctls Realize VFIO_DEVICE_GET_IRQ_INFO ioctl to retrieve VFIO_CCW_IO_IRQ information. Realize VFIO_DEVICE_SET_IRQS ioctl to set an eventfd fd for VFIO_CCW_IO_IRQ. Once a write operation to the ccw_io_region was performed, trigger a signal on this fd. Reviewed-by: Pierre Morel Signed-off-by: Dong Jia Shi Acked-by: Alex Williamson Message-Id: <20170317031743.40128-12-bjsdjshi@linux.vnet.ibm.com> Signed-off-by: Cornelia Huck --- drivers/s390/cio/vfio_ccw_ops.c | 123 +++++++++++++++++++++++++++- drivers/s390/cio/vfio_ccw_private.h | 4 + include/uapi/linux/vfio.h | 10 ++- 3 files changed, 134 insertions(+), 3 deletions(-) diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c index 125818cdf305..1294c5347410 100644 --- a/drivers/s390/cio/vfio_ccw_ops.c +++ b/drivers/s390/cio/vfio_ccw_ops.c @@ -202,6 +202,9 @@ static ssize_t vfio_ccw_mdev_write(struct mdev_device *mdev, if (region->ret_code != 0) return region->ret_code; + if (private->io_trigger) + eventfd_signal(private->io_trigger, 1); + return count; } @@ -209,7 +212,7 @@ static int vfio_ccw_mdev_get_device_info(struct vfio_device_info *info) { info->flags = VFIO_DEVICE_FLAGS_CCW | VFIO_DEVICE_FLAGS_RESET; info->num_regions = VFIO_CCW_NUM_REGIONS; - info->num_irqs = 0; + info->num_irqs = VFIO_CCW_NUM_IRQS; return 0; } @@ -230,6 +233,83 @@ static int vfio_ccw_mdev_get_region_info(struct vfio_region_info *info, } } +int vfio_ccw_mdev_get_irq_info(struct vfio_irq_info *info) +{ + if (info->index != VFIO_CCW_IO_IRQ_INDEX) + return -EINVAL; + + info->count = 1; + info->flags = VFIO_IRQ_INFO_EVENTFD; + + return 0; +} + +static int vfio_ccw_mdev_set_irqs(struct mdev_device *mdev, + uint32_t flags, + void __user *data) +{ + struct vfio_ccw_private *private; + struct eventfd_ctx **ctx; + + if (!(flags & VFIO_IRQ_SET_ACTION_TRIGGER)) + return -EINVAL; + + private = dev_get_drvdata(mdev_parent_dev(mdev)); + if (!private) + return -ENODEV; + + ctx = &private->io_trigger; + + switch (flags & VFIO_IRQ_SET_DATA_TYPE_MASK) { + case VFIO_IRQ_SET_DATA_NONE: + { + if (*ctx) + eventfd_signal(*ctx, 1); + return 0; + } + case VFIO_IRQ_SET_DATA_BOOL: + { + uint8_t trigger; + + if (get_user(trigger, (uint8_t __user *)data)) + return -EFAULT; + + if (trigger && *ctx) + eventfd_signal(*ctx, 1); + return 0; + } + case VFIO_IRQ_SET_DATA_EVENTFD: + { + int32_t fd; + + if (get_user(fd, (int32_t __user *)data)) + return -EFAULT; + + if (fd == -1) { + if (*ctx) + eventfd_ctx_put(*ctx); + *ctx = NULL; + } else if (fd >= 0) { + struct eventfd_ctx *efdctx; + + efdctx = eventfd_ctx_fdget(fd); + if (IS_ERR(efdctx)) + return PTR_ERR(efdctx); + + if (*ctx) + eventfd_ctx_put(*ctx); + + *ctx = efdctx; + } else + return -EINVAL; + + return 0; + } + default: + return -EINVAL; + } +} + static ssize_t vfio_ccw_mdev_ioctl(struct mdev_device *mdev, unsigned int cmd, unsigned long arg) @@ -277,6 +357,47 @@ static ssize_t vfio_ccw_mdev_ioctl(struct mdev_device *mdev, return copy_to_user((void __user *)arg, &info, minsz); } + case VFIO_DEVICE_GET_IRQ_INFO: + { + struct vfio_irq_info info; + + minsz = offsetofend(struct vfio_irq_info, count); + + if (copy_from_user(&info, (void __user *)arg, minsz)) + return -EFAULT; + + if (info.argsz < minsz || info.index >= VFIO_CCW_NUM_IRQS) + return -EINVAL; + + ret = vfio_ccw_mdev_get_irq_info(&info); + if (ret) + return ret; + + if (info.count == -1) + return -EINVAL; + + return copy_to_user((void __user *)arg, &info, minsz); + } + case VFIO_DEVICE_SET_IRQS: + { + struct vfio_irq_set hdr; + size_t data_size; + void __user *data; + + minsz = offsetofend(struct vfio_irq_set, count); + + if (copy_from_user(&hdr, (void __user *)arg, minsz)) + return -EFAULT; + + ret = vfio_set_irqs_validate_and_prepare(&hdr, 1, + VFIO_CCW_NUM_IRQS, + &data_size); + if (ret) + return ret; + + data = (void __user *)(arg + minsz); + return vfio_ccw_mdev_set_irqs(mdev, hdr.flags, data); + } case VFIO_DEVICE_RESET: return vfio_ccw_mdev_reset(mdev); default: diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h index 79e53378f212..dddab52913ed 100644 --- a/drivers/s390/cio/vfio_ccw_private.h +++ b/drivers/s390/cio/vfio_ccw_private.h @@ -11,6 +11,7 @@ #define _VFIO_CCW_PRIVATE_H_ #include +#include #include #include "css.h" @@ -29,6 +30,7 @@ * @cp: channel program for the current I/O operation * @irb: irb info received from interrupt * @scsw: scsw info + * @io_trigger: eventfd ctx for signaling userspace I/O results */ struct vfio_ccw_private { struct subchannel *sch; @@ -43,6 +45,8 @@ struct vfio_ccw_private { struct channel_program cp; struct irb irb; union scsw scsw; + + struct eventfd_ctx *io_trigger; } __aligned(8); extern int vfio_ccw_mdev_reg(struct subchannel *sch); diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index 3fd70ffe9d78..ae461050661a 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -449,8 +449,9 @@ enum { }; /* - * The vfio-ccw bus driver makes use of the following fixed region. - * Unimplemented regions return a size of zero. + * The vfio-ccw bus driver makes use of the following fixed region and + * IRQ index mapping. Unimplemented regions return a size of zero. + * Unimplemented IRQ types return a count of zero. */ enum { @@ -458,6 +459,11 @@ enum { VFIO_CCW_NUM_REGIONS }; +enum { + VFIO_CCW_IO_IRQ_INDEX, + VFIO_CCW_NUM_IRQS +}; + /** * VFIO_DEVICE_GET_PCI_HOT_RESET_INFO - _IORW(VFIO_TYPE, VFIO_BASE + 12, * struct vfio_pci_hot_reset_info) -- 2.20.1