Allow to extend the regions used by vfio-ccw. The first user will be handling of halt and clear subchannel. Reviewed-by: Eric Farman <farman@xxxxxxxxxxxxx> Reviewed-by: Farhan Ali <alifm@xxxxxxxxxxxxx> Signed-off-by: Cornelia Huck <cohuck@xxxxxxxxxx> --- drivers/s390/cio/vfio_ccw_ops.c | 187 ++++++++++++++++++++++++---- drivers/s390/cio/vfio_ccw_private.h | 38 ++++++ include/uapi/linux/vfio.h | 2 + 3 files changed, 201 insertions(+), 26 deletions(-) diff --git a/drivers/s390/cio/vfio_ccw_ops.c b/drivers/s390/cio/vfio_ccw_ops.c index 025c8a832bc8..5b989faa011f 100644 --- a/drivers/s390/cio/vfio_ccw_ops.c +++ b/drivers/s390/cio/vfio_ccw_ops.c @@ -3,13 +3,17 @@ * Physical device callbacks for vfio_ccw * * Copyright IBM Corp. 2017 + * Copyright Red Hat, Inc. 2019 * * Author(s): Dong Jia Shi <bjsdjshi@xxxxxxxxxxxxxxxxxx> * Xiao Feng Ren <renxiaof@xxxxxxxxxxxxxxxxxx> + * Cornelia Huck <cohuck@xxxxxxxxxx> */ #include <linux/vfio.h> #include <linux/mdev.h> +#include <linux/nospec.h> +#include <linux/slab.h> #include "vfio_ccw_private.h" @@ -157,27 +161,33 @@ static void vfio_ccw_mdev_release(struct mdev_device *mdev) { struct vfio_ccw_private *private = dev_get_drvdata(mdev_parent_dev(mdev)); + int i; vfio_unregister_notifier(mdev_dev(mdev), VFIO_IOMMU_NOTIFY, &private->nb); + + for (i = 0; i < private->num_regions; i++) + private->region[i].ops->release(private, &private->region[i]); + + private->num_regions = 0; + kfree(private->region); + private->region = NULL; } -static ssize_t vfio_ccw_mdev_read(struct mdev_device *mdev, - char __user *buf, - size_t count, - loff_t *ppos) +static ssize_t vfio_ccw_mdev_read_io_region(struct vfio_ccw_private *private, + char __user *buf, size_t count, + loff_t *ppos) { - struct vfio_ccw_private *private; + loff_t pos = *ppos & VFIO_CCW_OFFSET_MASK; struct ccw_io_region *region; int ret; - if (*ppos + count > sizeof(*region)) + if (pos + count > sizeof(*region)) return -EINVAL; - private = dev_get_drvdata(mdev_parent_dev(mdev)); mutex_lock(&private->io_mutex); region = private->io_region; - if (copy_to_user(buf, (void *)region + *ppos, count)) + if (copy_to_user(buf, (void *)region + pos, count)) ret = -EFAULT; else ret = count; @@ -185,24 +195,47 @@ static ssize_t vfio_ccw_mdev_read(struct mdev_device *mdev, return ret; } -static ssize_t vfio_ccw_mdev_write(struct mdev_device *mdev, - const char __user *buf, - size_t count, - loff_t *ppos) +static ssize_t vfio_ccw_mdev_read(struct mdev_device *mdev, + char __user *buf, + size_t count, + loff_t *ppos) { + unsigned int index = VFIO_CCW_OFFSET_TO_INDEX(*ppos); struct vfio_ccw_private *private; + + private = dev_get_drvdata(mdev_parent_dev(mdev)); + + if (index >= VFIO_CCW_NUM_REGIONS + private->num_regions) + return -EINVAL; + + switch (index) { + case VFIO_CCW_CONFIG_REGION_INDEX: + return vfio_ccw_mdev_read_io_region(private, buf, count, ppos); + default: + index -= VFIO_CCW_NUM_REGIONS; + return private->region[index].ops->read(private, buf, count, + ppos); + } + + return -EINVAL; +} + +static ssize_t vfio_ccw_mdev_write_io_region(struct vfio_ccw_private *private, + const char __user *buf, + size_t count, loff_t *ppos) +{ + loff_t pos = *ppos & VFIO_CCW_OFFSET_MASK; struct ccw_io_region *region; int ret; - if (*ppos + count > sizeof(*region)) + if (pos + count > sizeof(*region)) return -EINVAL; - private = dev_get_drvdata(mdev_parent_dev(mdev)); if (!mutex_trylock(&private->io_mutex)) return -EAGAIN; region = private->io_region; - if (copy_from_user((void *)region + *ppos, buf, count)) { + if (copy_from_user((void *)region + pos, buf, count)) { ret = -EFAULT; goto out_unlock; } @@ -217,19 +250,52 @@ static ssize_t vfio_ccw_mdev_write(struct mdev_device *mdev, return ret; } -static int vfio_ccw_mdev_get_device_info(struct vfio_device_info *info) +static ssize_t vfio_ccw_mdev_write(struct mdev_device *mdev, + const char __user *buf, + size_t count, + loff_t *ppos) { + unsigned int index = VFIO_CCW_OFFSET_TO_INDEX(*ppos); + struct vfio_ccw_private *private; + + private = dev_get_drvdata(mdev_parent_dev(mdev)); + + if (index >= VFIO_CCW_NUM_REGIONS + private->num_regions) + return -EINVAL; + + switch (index) { + case VFIO_CCW_CONFIG_REGION_INDEX: + return vfio_ccw_mdev_write_io_region(private, buf, count, ppos); + default: + index -= VFIO_CCW_NUM_REGIONS; + return private->region[index].ops->write(private, buf, count, + ppos); + } + + return -EINVAL; +} + +static int vfio_ccw_mdev_get_device_info(struct vfio_device_info *info, + struct mdev_device *mdev) +{ + struct vfio_ccw_private *private; + + private = dev_get_drvdata(mdev_parent_dev(mdev)); info->flags = VFIO_DEVICE_FLAGS_CCW | VFIO_DEVICE_FLAGS_RESET; - info->num_regions = VFIO_CCW_NUM_REGIONS; + info->num_regions = VFIO_CCW_NUM_REGIONS + private->num_regions; info->num_irqs = VFIO_CCW_NUM_IRQS; return 0; } static int vfio_ccw_mdev_get_region_info(struct vfio_region_info *info, - u16 *cap_type_id, - void **cap_type) + struct mdev_device *mdev, + unsigned long arg) { + struct vfio_ccw_private *private; + int i; + + private = dev_get_drvdata(mdev_parent_dev(mdev)); switch (info->index) { case VFIO_CCW_CONFIG_REGION_INDEX: info->offset = 0; @@ -237,9 +303,55 @@ static int vfio_ccw_mdev_get_region_info(struct vfio_region_info *info, info->flags = VFIO_REGION_INFO_FLAG_READ | VFIO_REGION_INFO_FLAG_WRITE; return 0; - default: - return -EINVAL; + default: /* all other regions are handled via capability chain */ + { + struct vfio_info_cap caps = { .buf = NULL, .size = 0 }; + struct vfio_region_info_cap_type cap_type = { + .header.id = VFIO_REGION_INFO_CAP_TYPE, + .header.version = 1 }; + int ret; + + if (info->index >= + VFIO_CCW_NUM_REGIONS + private->num_regions) + return -EINVAL; + + info->index = array_index_nospec(info->index, + VFIO_CCW_NUM_REGIONS + + private->num_regions); + + i = info->index - VFIO_CCW_NUM_REGIONS; + + info->offset = VFIO_CCW_INDEX_TO_OFFSET(info->index); + info->size = private->region[i].size; + info->flags = private->region[i].flags; + + cap_type.type = private->region[i].type; + cap_type.subtype = private->region[i].subtype; + + ret = vfio_info_add_capability(&caps, &cap_type.header, + sizeof(cap_type)); + if (ret) + return ret; + + info->flags |= VFIO_REGION_INFO_FLAG_CAPS; + if (info->argsz < sizeof(*info) + caps.size) { + info->argsz = sizeof(*info) + caps.size; + info->cap_offset = 0; + } else { + vfio_info_cap_shift(&caps, sizeof(*info)); + if (copy_to_user((void __user *)arg + sizeof(*info), + caps.buf, caps.size)) { + kfree(caps.buf); + return -EFAULT; + } + info->cap_offset = sizeof(*info); + } + + kfree(caps.buf); + + } } + return 0; } static int vfio_ccw_mdev_get_irq_info(struct vfio_irq_info *info) @@ -316,6 +428,32 @@ static int vfio_ccw_mdev_set_irqs(struct mdev_device *mdev, } } +int vfio_ccw_register_dev_region(struct vfio_ccw_private *private, + unsigned int subtype, + const struct vfio_ccw_regops *ops, + size_t size, u32 flags, void *data) +{ + struct vfio_ccw_region *region; + + region = krealloc(private->region, + (private->num_regions + 1) * sizeof(*region), + GFP_KERNEL); + if (!region) + return -ENOMEM; + + private->region = region; + private->region[private->num_regions].type = VFIO_REGION_TYPE_CCW; + private->region[private->num_regions].subtype = subtype; + private->region[private->num_regions].ops = ops; + private->region[private->num_regions].size = size; + private->region[private->num_regions].flags = flags; + private->region[private->num_regions].data = data; + + private->num_regions++; + + return 0; +} + static ssize_t vfio_ccw_mdev_ioctl(struct mdev_device *mdev, unsigned int cmd, unsigned long arg) @@ -336,7 +474,7 @@ static ssize_t vfio_ccw_mdev_ioctl(struct mdev_device *mdev, if (info.argsz < minsz) return -EINVAL; - ret = vfio_ccw_mdev_get_device_info(&info); + ret = vfio_ccw_mdev_get_device_info(&info, mdev); if (ret) return ret; @@ -345,8 +483,6 @@ static ssize_t vfio_ccw_mdev_ioctl(struct mdev_device *mdev, case VFIO_DEVICE_GET_REGION_INFO: { struct vfio_region_info info; - u16 cap_type_id = 0; - void *cap_type = NULL; minsz = offsetofend(struct vfio_region_info, offset); @@ -356,8 +492,7 @@ static ssize_t vfio_ccw_mdev_ioctl(struct mdev_device *mdev, if (info.argsz < minsz) return -EINVAL; - ret = vfio_ccw_mdev_get_region_info(&info, &cap_type_id, - &cap_type); + ret = vfio_ccw_mdev_get_region_info(&info, mdev, arg); if (ret) return ret; diff --git a/drivers/s390/cio/vfio_ccw_private.h b/drivers/s390/cio/vfio_ccw_private.h index 32173cbd838d..d888a2573470 100644 --- a/drivers/s390/cio/vfio_ccw_private.h +++ b/drivers/s390/cio/vfio_ccw_private.h @@ -3,9 +3,11 @@ * Private stuff for vfio_ccw driver * * Copyright IBM Corp. 2017 + * Copyright Red Hat, Inc. 2019 * * Author(s): Dong Jia Shi <bjsdjshi@xxxxxxxxxxxxxxxxxx> * Xiao Feng Ren <renxiaof@xxxxxxxxxxxxxxxxxx> + * Cornelia Huck <cohuck@xxxxxxxxxx> */ #ifndef _VFIO_CCW_PRIVATE_H_ @@ -19,6 +21,38 @@ #include "css.h" #include "vfio_ccw_cp.h" +#define VFIO_CCW_OFFSET_SHIFT 10 +#define VFIO_CCW_OFFSET_TO_INDEX(off) (off >> VFIO_CCW_OFFSET_SHIFT) +#define VFIO_CCW_INDEX_TO_OFFSET(index) ((u64)(index) << VFIO_CCW_OFFSET_SHIFT) +#define VFIO_CCW_OFFSET_MASK (((u64)(1) << VFIO_CCW_OFFSET_SHIFT) - 1) + +/* capability chain handling similar to vfio-pci */ +struct vfio_ccw_private; +struct vfio_ccw_region; + +struct vfio_ccw_regops { + ssize_t (*read)(struct vfio_ccw_private *private, char __user *buf, + size_t count, loff_t *ppos); + ssize_t (*write)(struct vfio_ccw_private *private, + const char __user *buf, size_t count, loff_t *ppos); + void (*release)(struct vfio_ccw_private *private, + struct vfio_ccw_region *region); +}; + +struct vfio_ccw_region { + u32 type; + u32 subtype; + const struct vfio_ccw_regops *ops; + void *data; + size_t size; + u32 flags; +}; + +int vfio_ccw_register_dev_region(struct vfio_ccw_private *private, + unsigned int subtype, + const struct vfio_ccw_regops *ops, + size_t size, u32 flags, void *data); + /** * struct vfio_ccw_private * @sch: pointer to the subchannel @@ -29,6 +63,8 @@ * @nb: notifier for vfio events * @io_region: MMIO region to input/output I/O arguments/results * @io_mutex: protect against concurrent update of I/O regions + * @region: additional regions for other subchannel operations + * @num_regions: number of additional regions * @cp: channel program for the current I/O operation * @irb: irb info received from interrupt * @scsw: scsw info @@ -44,6 +80,8 @@ struct vfio_ccw_private { struct notifier_block nb; struct ccw_io_region *io_region; struct mutex io_mutex; + struct vfio_ccw_region *region; + int num_regions; struct channel_program cp; struct irb irb; diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index 02bb7ad6e986..56e2413d3e00 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -353,6 +353,8 @@ struct vfio_region_gfx_edid { #define VFIO_DEVICE_GFX_LINK_STATE_DOWN 2 }; +#define VFIO_REGION_TYPE_CCW (2) + /* * 10de vendor sub-type * -- 2.17.2