diff options
Diffstat (limited to 'drivers/iommu/iommufd/iommufd_private.h')
| -rw-r--r-- | drivers/iommu/iommufd/iommufd_private.h | 152 |
1 files changed, 126 insertions, 26 deletions
diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h index 2c58670011..abae041e25 100644 --- a/drivers/iommu/iommufd/iommufd_private.h +++ b/drivers/iommu/iommufd/iommufd_private.h @@ -8,6 +8,9 @@ #include <linux/xarray.h> #include <linux/refcount.h> #include <linux/uaccess.h> +#include <linux/iommu.h> +#include <linux/iova_bitmap.h> +#include <uapi/linux/iommufd.h> struct iommu_domain; struct iommu_group; @@ -18,6 +21,7 @@ struct iommufd_ctx { struct file *file; struct xarray objects; struct xarray groups; + wait_queue_head_t destroy_wait; u8 account_mode; /* Compatibility with VFIO no iommu */ @@ -70,6 +74,13 @@ int iopt_unmap_iova(struct io_pagetable *iopt, unsigned long iova, unsigned long length, unsigned long *unmapped); int iopt_unmap_all(struct io_pagetable *iopt, unsigned long *unmapped); +int iopt_read_and_clear_dirty_data(struct io_pagetable *iopt, + struct iommu_domain *domain, + unsigned long flags, + struct iommu_hwpt_get_dirty_bitmap *bitmap); +int iopt_set_dirty_tracking(struct io_pagetable *iopt, + struct iommu_domain *domain, bool enable); + void iommufd_access_notify_unmap(struct io_pagetable *iopt, unsigned long iova, unsigned long length); int iopt_table_add_domain(struct io_pagetable *iopt, @@ -113,7 +124,8 @@ enum iommufd_object_type { IOMMUFD_OBJ_NONE, IOMMUFD_OBJ_ANY = IOMMUFD_OBJ_NONE, IOMMUFD_OBJ_DEVICE, - IOMMUFD_OBJ_HW_PAGETABLE, + IOMMUFD_OBJ_HWPT_PAGING, + IOMMUFD_OBJ_HWPT_NESTED, IOMMUFD_OBJ_IOAS, IOMMUFD_OBJ_ACCESS, #ifdef CONFIG_IOMMUFD_TEST @@ -124,7 +136,7 @@ enum iommufd_object_type { /* Base struct for all objects with a userspace ID handle. */ struct iommufd_object { - struct rw_semaphore destroy_rwsem; + refcount_t shortterm_users; refcount_t users; enum iommufd_object_type type; unsigned int id; @@ -132,10 +144,15 @@ struct iommufd_object { static inline bool iommufd_lock_obj(struct iommufd_object *obj) { - if (!down_read_trylock(&obj->destroy_rwsem)) + if (!refcount_inc_not_zero(&obj->users)) return false; - if (!refcount_inc_not_zero(&obj->users)) { - up_read(&obj->destroy_rwsem); + if (!refcount_inc_not_zero(&obj->shortterm_users)) { + /* + * If the caller doesn't already have a ref on obj this must be + * called under the xa_lock. Otherwise the caller is holding a + * ref on users. Thus it cannot be one before this decrement. + */ + refcount_dec(&obj->users); return false; } return true; @@ -143,10 +160,16 @@ static inline bool iommufd_lock_obj(struct iommufd_object *obj) struct iommufd_object *iommufd_get_object(struct iommufd_ctx *ictx, u32 id, enum iommufd_object_type type); -static inline void iommufd_put_object(struct iommufd_object *obj) +static inline void iommufd_put_object(struct iommufd_ctx *ictx, + struct iommufd_object *obj) { + /* + * Users first, then shortterm so that REMOVE_WAIT_SHORTTERM never sees + * a spurious !0 users with a 0 shortterm_users. + */ refcount_dec(&obj->users); - up_read(&obj->destroy_rwsem); + if (refcount_dec_and_test(&obj->shortterm_users)) + wake_up_interruptible_all(&ictx->destroy_wait); } void iommufd_object_abort(struct iommufd_ctx *ictx, struct iommufd_object *obj); @@ -154,24 +177,56 @@ void iommufd_object_abort_and_destroy(struct iommufd_ctx *ictx, struct iommufd_object *obj); void iommufd_object_finalize(struct iommufd_ctx *ictx, struct iommufd_object *obj); -void __iommufd_object_destroy_user(struct iommufd_ctx *ictx, - struct iommufd_object *obj, bool allow_fail); + +enum { + REMOVE_WAIT_SHORTTERM = 1, +}; +int iommufd_object_remove(struct iommufd_ctx *ictx, + struct iommufd_object *to_destroy, u32 id, + unsigned int flags); + +/* + * The caller holds a users refcount and wants to destroy the object. At this + * point the caller has no shortterm_users reference and at least the xarray + * will be holding one. + */ static inline void iommufd_object_destroy_user(struct iommufd_ctx *ictx, struct iommufd_object *obj) { - __iommufd_object_destroy_user(ictx, obj, false); + int ret; + + ret = iommufd_object_remove(ictx, obj, obj->id, REMOVE_WAIT_SHORTTERM); + + /* + * If there is a bug and we couldn't destroy the object then we did put + * back the caller's users refcount and will eventually try to free it + * again during close. + */ + WARN_ON(ret); } -static inline void iommufd_object_deref_user(struct iommufd_ctx *ictx, - struct iommufd_object *obj) + +/* + * The HWPT allocated by autodomains is used in possibly many devices and + * is automatically destroyed when its refcount reaches zero. + * + * If userspace uses the HWPT manually, even for a short term, then it will + * disrupt this refcounting and the auto-free in the kernel will not work. + * Userspace that tries to use the automatically allocated HWPT must be careful + * to ensure that it is consistently destroyed, eg by not racing accesses + * and by not attaching an automatic HWPT to a device manually. + */ +static inline void +iommufd_object_put_and_try_destroy(struct iommufd_ctx *ictx, + struct iommufd_object *obj) { - __iommufd_object_destroy_user(ictx, obj, true); + iommufd_object_remove(ictx, obj, obj->id, 0); } struct iommufd_object *_iommufd_object_alloc(struct iommufd_ctx *ictx, size_t size, enum iommufd_object_type type); -#define iommufd_object_alloc(ictx, ptr, type) \ +#define __iommufd_object_alloc(ictx, ptr, type, obj) \ container_of(_iommufd_object_alloc( \ ictx, \ sizeof(*(ptr)) + BUILD_BUG_ON_ZERO( \ @@ -180,6 +235,9 @@ struct iommufd_object *_iommufd_object_alloc(struct iommufd_ctx *ictx, type), \ typeof(*(ptr)), obj) +#define iommufd_object_alloc(ictx, ptr, type) \ + __iommufd_object_alloc(ictx, ptr, type, obj) + /* * The IO Address Space (IOAS) pagetable is a virtual page table backed by the * io_pagetable object. It is a user controlled mapping of IOVA -> PFNs. The @@ -222,6 +280,8 @@ int iommufd_option_rlimit_mode(struct iommu_option *cmd, struct iommufd_ctx *ictx); int iommufd_vfio_ioas(struct iommufd_ucmd *ucmd); +int iommufd_check_iova_range(struct io_pagetable *iopt, + struct iommu_hwpt_get_dirty_bitmap *bitmap); /* * A HW pagetable is called an iommu_domain inside the kernel. This user object @@ -231,35 +291,75 @@ int iommufd_vfio_ioas(struct iommufd_ucmd *ucmd); */ struct iommufd_hw_pagetable { struct iommufd_object obj; - struct iommufd_ioas *ioas; struct iommu_domain *domain; +}; + +struct iommufd_hwpt_paging { + struct iommufd_hw_pagetable common; + struct iommufd_ioas *ioas; bool auto_domain : 1; bool enforce_cache_coherency : 1; bool msi_cookie : 1; + bool nest_parent : 1; /* Head at iommufd_ioas::hwpt_list */ struct list_head hwpt_item; }; -struct iommufd_hw_pagetable * -iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas, - struct iommufd_device *idev, bool immediate_attach); -int iommufd_hw_pagetable_enforce_cc(struct iommufd_hw_pagetable *hwpt); +struct iommufd_hwpt_nested { + struct iommufd_hw_pagetable common; + struct iommufd_hwpt_paging *parent; +}; + +static inline bool hwpt_is_paging(struct iommufd_hw_pagetable *hwpt) +{ + return hwpt->obj.type == IOMMUFD_OBJ_HWPT_PAGING; +} + +static inline struct iommufd_hwpt_paging * +to_hwpt_paging(struct iommufd_hw_pagetable *hwpt) +{ + return container_of(hwpt, struct iommufd_hwpt_paging, common); +} + +static inline struct iommufd_hwpt_paging * +iommufd_get_hwpt_paging(struct iommufd_ucmd *ucmd, u32 id) +{ + return container_of(iommufd_get_object(ucmd->ictx, id, + IOMMUFD_OBJ_HWPT_PAGING), + struct iommufd_hwpt_paging, common.obj); +} +int iommufd_hwpt_set_dirty_tracking(struct iommufd_ucmd *ucmd); +int iommufd_hwpt_get_dirty_bitmap(struct iommufd_ucmd *ucmd); + +struct iommufd_hwpt_paging * +iommufd_hwpt_paging_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas, + struct iommufd_device *idev, u32 flags, + bool immediate_attach, + const struct iommu_user_data *user_data); int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt, struct iommufd_device *idev); struct iommufd_hw_pagetable * iommufd_hw_pagetable_detach(struct iommufd_device *idev); -void iommufd_hw_pagetable_destroy(struct iommufd_object *obj); -void iommufd_hw_pagetable_abort(struct iommufd_object *obj); +void iommufd_hwpt_paging_destroy(struct iommufd_object *obj); +void iommufd_hwpt_paging_abort(struct iommufd_object *obj); +void iommufd_hwpt_nested_destroy(struct iommufd_object *obj); +void iommufd_hwpt_nested_abort(struct iommufd_object *obj); int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd); static inline void iommufd_hw_pagetable_put(struct iommufd_ctx *ictx, struct iommufd_hw_pagetable *hwpt) { - lockdep_assert_not_held(&hwpt->ioas->mutex); - if (hwpt->auto_domain) - iommufd_object_deref_user(ictx, &hwpt->obj); - else - refcount_dec(&hwpt->obj.users); + if (hwpt->obj.type == IOMMUFD_OBJ_HWPT_PAGING) { + struct iommufd_hwpt_paging *hwpt_paging = to_hwpt_paging(hwpt); + + lockdep_assert_not_held(&hwpt_paging->ioas->mutex); + + if (hwpt_paging->auto_domain) { + iommufd_object_put_and_try_destroy(ictx, &hwpt->obj); + return; + } + } + refcount_dec(&hwpt->obj.users); } struct iommufd_group { |