From: Liu Yi L <[email protected]> This patch adds VFIO_IOMMU_PASID_REQUEST ioctl which aims to passdown PASID allocation/free request from the virtual iommu. This is required to get PASID managed in system-wide.
Cc: Kevin Tian <[email protected]> Signed-off-by: Liu Yi L <[email protected]> Signed-off-by: Yi Sun <[email protected]> Signed-off-by: Jacob Pan <[email protected]> --- drivers/vfio/vfio_iommu_type1.c | 125 ++++++++++++++++++++++++++++++++++++++++ include/uapi/linux/vfio.h | 25 ++++++++ 2 files changed, 150 insertions(+) diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 6fda4fb..d5e0c01 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -1832,6 +1832,94 @@ static int vfio_cache_inv_fn(struct device *dev, void *data) return iommu_cache_invalidate(dc->domain, dev, &ustruct->info); } +static int vfio_iommu_type1_pasid_alloc(struct vfio_iommu *iommu, + int min_pasid, + int max_pasid) +{ + int ret; + ioasid_t pasid; + struct mm_struct *mm = NULL; + + mutex_lock(&iommu->lock); + if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu)) { + ret = -EINVAL; + goto out_unlock; + } + mm = get_task_mm(current); + /* Jacob: track ioasid allocation owner by mm */ + pasid = ioasid_alloc((struct ioasid_set *)mm, min_pasid, + max_pasid, NULL); + if (pasid == INVALID_IOASID) { + ret = -ENOSPC; + goto out_unlock; + } + ret = pasid; +out_unlock: + mutex_unlock(&iommu->lock); + if (mm) + mmput(mm); + return ret; +} + +static int vfio_iommu_type1_pasid_free(struct vfio_iommu *iommu, int pasid) +{ + struct mm_struct *mm = NULL; + void *pdata; + int ret = 0; + + mutex_lock(&iommu->lock); + if (!IS_IOMMU_CAP_DOMAIN_IN_CONTAINER(iommu)) { + ret = -EINVAL; + goto out_unlock; + } + pr_debug("%s: pasid: %d\n", __func__, pasid); + + /** + * TODO: + * a) for pasid free, needs to return error if free failed + * b) Sanity check: check if the pasid is allocated to the + * current process such check may be in + * vendor specific pasid_free callback or + * in generic layer + * c) clean up device list and free p_alloc structure + * + * Jacob: + * There are two cases free could fail: + * 1. free pasid by non-owner, we can use ioasid_set to track mm, if + * the set does not match, caller is not permitted to free. + * 2. free before unbind all devices, we can check if ioasid private + * data, if data != NULL, then fail to free. + */ + + mm = get_task_mm(current); + pdata = ioasid_find((struct ioasid_set *)mm, pasid, NULL); + if (IS_ERR(pdata)) { + if (pdata == ERR_PTR(-ENOENT)) + pr_debug("pasid %d is not allocated\n", pasid); + else if (pdata == ERR_PTR(-EACCES)) + pr_debug("Not owner of pasid %d," + "no pasid free allowed\n", pasid); + else + pr_debug("error happened during searching" + " pasid: %d\n", pasid); + ret = -EPERM; + goto out_unlock; + } + if (pdata) { + pr_debug("Cannot free pasid %d with private data\n", pasid); + /* Expect PASID has no private data if not bond */ + ret = -EBUSY; + goto out_unlock; + } + ioasid_free(pasid); + +out_unlock: + if (mm) + mmput(mm); + mutex_unlock(&iommu->lock); + return ret; +} + static long vfio_iommu_type1_ioctl(void *iommu_data, unsigned int cmd, unsigned long arg) { @@ -1936,6 +2024,43 @@ static long vfio_iommu_type1_ioctl(void *iommu_data, &ustruct); mutex_unlock(&iommu->lock); return ret; + + } else if (cmd == VFIO_IOMMU_PASID_REQUEST) { + struct vfio_iommu_type1_pasid_request req; + int min_pasid, max_pasid, pasid; + + minsz = offsetofend(struct vfio_iommu_type1_pasid_request, + flag); + + if (copy_from_user(&req, (void __user *)arg, minsz)) + return -EFAULT; + + if (req.argsz < minsz) + return -EINVAL; + + switch (req.flag) { + /** + * TODO: min_pasid and max_pasid align with + * typedef unsigned int ioasid_t + */ + case VFIO_IOMMU_PASID_ALLOC: + if (copy_from_user(&min_pasid, + (void __user *)arg + minsz, sizeof(min_pasid))) + return -EFAULT; + if (copy_from_user(&max_pasid, + (void __user *)arg + minsz + sizeof(min_pasid), + sizeof(max_pasid))) + return -EFAULT; + return vfio_iommu_type1_pasid_alloc(iommu, + min_pasid, max_pasid); + case VFIO_IOMMU_PASID_FREE: + if (copy_from_user(&pasid, + (void __user *)arg + minsz, sizeof(pasid))) + return -EFAULT; + return vfio_iommu_type1_pasid_free(iommu, pasid); + default: + return -EINVAL; + } } return -ENOTTY; diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index 055aa9b..af03c9f 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -798,6 +798,31 @@ struct vfio_iommu_type1_cache_invalidate { }; #define VFIO_IOMMU_CACHE_INVALIDATE _IO(VFIO_TYPE, VFIO_BASE + 24) +/* + * @flag=VFIO_IOMMU_PASID_ALLOC, refer to the @min_pasid and @max_pasid fields + * @flag=VFIO_IOMMU_PASID_FREE, refer to @pasid field + */ +struct vfio_iommu_type1_pasid_request { + __u32 argsz; +#define VFIO_IOMMU_PASID_ALLOC (1 << 0) +#define VFIO_IOMMU_PASID_FREE (1 << 1) + __u32 flag; + union { + struct { + int min_pasid; + int max_pasid; + }; + int pasid; + }; +}; + +/** + * VFIO_IOMMU_PASID_REQUEST - _IOWR(VFIO_TYPE, VFIO_BASE + 27, + * struct vfio_iommu_type1_pasid_request) + * + */ +#define VFIO_IOMMU_PASID_REQUEST _IO(VFIO_TYPE, VFIO_BASE + 27) + /* -------- Additional API for SPAPR TCE (Server POWERPC) IOMMU -------- */ /* -- 2.7.4 _______________________________________________ iommu mailing list [email protected] https://lists.linuxfoundation.org/mailman/listinfo/iommu
