Extract all common procedure, between the iommufd_access_attach() API and the new iommufd_access_replace() API, to an iommufd_access_change_pt() helper. Add iommufd_access_replace() function for VFIO emulated pathway to use. Suggested-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx> --- drivers/iommu/iommufd/device.c | 53 +++++++++++++++++++------ include/linux/iommufd.h | 1 + tools/testing/selftests/iommu/iommfd*.c | 0 3 files changed, 42 insertions(+), 12 deletions(-) create mode 100644 tools/testing/selftests/iommu/iommfd*.c diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c index 6f7b349ba8f5..b6d61e886fbb 100644 --- a/drivers/iommu/iommufd/device.c +++ b/drivers/iommu/iommufd/device.c @@ -752,38 +752,67 @@ void iommufd_access_detach(struct iommufd_access *access) } EXPORT_SYMBOL_NS_GPL(iommufd_access_detach, IOMMUFD); -int iommufd_access_attach(struct iommufd_access *access, u32 ioas_id) +static int iommufd_access_change_pt(struct iommufd_access *access, u32 ioas_id) { struct iommufd_ioas *new_ioas; - int rc = 0; + int rc; - mutex_lock(&access->ioas_lock); - if (access->ioas != NULL && access->ioas->obj.id != ioas_id) { - mutex_unlock(&access->ioas_lock); - return -EINVAL; - } + lockdep_assert_held(&access->ioas_lock); new_ioas = iommufd_get_ioas(access->ictx, ioas_id); - if (IS_ERR(new_ioas)) { - mutex_unlock(&access->ioas_lock); + if (IS_ERR(new_ioas)) return PTR_ERR(new_ioas); - } rc = iopt_add_access(&new_ioas->iopt, access); if (rc) { - mutex_unlock(&access->ioas_lock); iommufd_put_object(&new_ioas->obj); return rc; } iommufd_ref_to_users(&new_ioas->obj); + if (access->ioas) + __iommufd_access_detach(access); access->ioas = new_ioas; access->ioas_unpin = new_ioas; - mutex_unlock(&access->ioas_lock); return 0; } + +int iommufd_access_attach(struct iommufd_access *access, u32 ioas_id) +{ + int rc; + + mutex_lock(&access->ioas_lock); + if (access->ioas != NULL && access->ioas->obj.id != ioas_id) { + mutex_unlock(&access->ioas_lock); + return -EINVAL; + } + + rc = iommufd_access_change_pt(access, ioas_id); + mutex_unlock(&access->ioas_lock); + return rc; +} EXPORT_SYMBOL_NS_GPL(iommufd_access_attach, IOMMUFD); +int iommufd_access_replace(struct iommufd_access *access, u32 ioas_id) +{ + int rc; + + mutex_lock(&access->ioas_lock); + if (!access->ioas) { + mutex_unlock(&access->ioas_lock); + return -ENOENT; + } + if (access->ioas->obj.id == ioas_id) { + mutex_unlock(&access->ioas_lock); + return 0; + } + + rc = iommufd_access_change_pt(access, ioas_id); + mutex_unlock(&access->ioas_lock); + return rc; +} +EXPORT_SYMBOL_NS_GPL(iommufd_access_replace, IOMMUFD); + /** * iommufd_access_notify_unmap - Notify users of an iopt to stop using it * @iopt: iopt to work on diff --git a/include/linux/iommufd.h b/include/linux/iommufd.h index 135dc2a28156..6752c58226d1 100644 --- a/include/linux/iommufd.h +++ b/include/linux/iommufd.h @@ -48,6 +48,7 @@ iommufd_access_create(struct iommufd_ctx *ictx, const struct iommufd_access_ops *ops, void *data, u32 *id); void iommufd_access_destroy(struct iommufd_access *access); int iommufd_access_attach(struct iommufd_access *access, u32 ioas_id); +int iommufd_access_replace(struct iommufd_access *access, u32 ioas_id); void iommufd_access_detach(struct iommufd_access *access); void iommufd_ctx_get(struct iommufd_ctx *ictx); diff --git a/tools/testing/selftests/iommu/iommfd*.c b/tools/testing/selftests/iommu/iommfd*.c new file mode 100644 index 000000000000..e69de29bb2d1 -- 2.40.0