| #ifndef __DRM_VMA_MANAGER_H__ |
| #define __DRM_VMA_MANAGER_H__ |
| |
| /* |
| * Copyright (c) 2013 David Herrmann <dh.herrmann@gmail.com> |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a |
| * copy of this software and associated documentation files (the "Software"), |
| * to deal in the Software without restriction, including without limitation |
| * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| * and/or sell copies of the Software, and to permit persons to whom the |
| * Software is furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in |
| * all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR |
| * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, |
| * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR |
| * OTHER DEALINGS IN THE SOFTWARE. |
| */ |
| |
| #include <drm/drm_mm.h> |
| #include <linux/mm.h> |
| #include <linux/module.h> |
| #include <linux/rbtree.h> |
| #include <linux/spinlock.h> |
| #include <linux/types.h> |
| |
| struct drm_file; |
| |
| struct drm_vma_offset_file { |
| struct rb_node vm_rb; |
| struct drm_file *vm_tag; |
| unsigned long vm_count; |
| }; |
| |
| struct drm_vma_offset_node { |
| rwlock_t vm_lock; |
| struct drm_mm_node vm_node; |
| struct rb_root vm_files; |
| bool readonly:1; |
| }; |
| |
| struct drm_vma_offset_manager { |
| rwlock_t vm_lock; |
| struct drm_mm vm_addr_space_mm; |
| }; |
| |
| void drm_vma_offset_manager_init(struct drm_vma_offset_manager *mgr, |
| unsigned long page_offset, unsigned long size); |
| void drm_vma_offset_manager_destroy(struct drm_vma_offset_manager *mgr); |
| |
| struct drm_vma_offset_node *drm_vma_offset_lookup_locked(struct drm_vma_offset_manager *mgr, |
| unsigned long start, |
| unsigned long pages); |
| int drm_vma_offset_add(struct drm_vma_offset_manager *mgr, |
| struct drm_vma_offset_node *node, unsigned long pages); |
| void drm_vma_offset_remove(struct drm_vma_offset_manager *mgr, |
| struct drm_vma_offset_node *node); |
| |
| int drm_vma_node_allow(struct drm_vma_offset_node *node, struct drm_file *tag); |
| void drm_vma_node_revoke(struct drm_vma_offset_node *node, |
| struct drm_file *tag); |
| bool drm_vma_node_is_allowed(struct drm_vma_offset_node *node, |
| struct drm_file *tag); |
| |
| /** |
| * drm_vma_offset_exact_lookup_locked() - Look up node by exact address |
| * @mgr: Manager object |
| * @start: Start address (page-based, not byte-based) |
| * @pages: Size of object (page-based) |
| * |
| * Same as drm_vma_offset_lookup_locked() but does not allow any offset into the node. |
| * It only returns the exact object with the given start address. |
| * |
| * RETURNS: |
| * Node at exact start address @start. |
| */ |
| static inline struct drm_vma_offset_node * |
| drm_vma_offset_exact_lookup_locked(struct drm_vma_offset_manager *mgr, |
| unsigned long start, |
| unsigned long pages) |
| { |
| struct drm_vma_offset_node *node; |
| |
| node = drm_vma_offset_lookup_locked(mgr, start, pages); |
| return (node && node->vm_node.start == start) ? node : NULL; |
| } |
| |
| /** |
| * drm_vma_offset_lock_lookup() - Lock lookup for extended private use |
| * @mgr: Manager object |
| * |
| * Lock VMA manager for extended lookups. Only locked VMA function calls |
| * are allowed while holding this lock. All other contexts are blocked from VMA |
| * until the lock is released via drm_vma_offset_unlock_lookup(). |
| * |
| * Use this if you need to take a reference to the objects returned by |
| * drm_vma_offset_lookup_locked() before releasing this lock again. |
| * |
| * This lock must not be used for anything else than extended lookups. You must |
| * not call any other VMA helpers while holding this lock. |
| * |
| * Note: You're in atomic-context while holding this lock! |
| */ |
| static inline void drm_vma_offset_lock_lookup(struct drm_vma_offset_manager *mgr) |
| { |
| read_lock(&mgr->vm_lock); |
| } |
| |
| /** |
| * drm_vma_offset_unlock_lookup() - Unlock lookup for extended private use |
| * @mgr: Manager object |
| * |
| * Release lookup-lock. See drm_vma_offset_lock_lookup() for more information. |
| */ |
| static inline void drm_vma_offset_unlock_lookup(struct drm_vma_offset_manager *mgr) |
| { |
| read_unlock(&mgr->vm_lock); |
| } |
| |
| /** |
| * drm_vma_node_reset() - Initialize or reset node object |
| * @node: Node to initialize or reset |
| * |
| * Reset a node to its initial state. This must be called before using it with |
| * any VMA offset manager. |
| * |
| * This must not be called on an already allocated node, or you will leak |
| * memory. |
| */ |
| static inline void drm_vma_node_reset(struct drm_vma_offset_node *node) |
| { |
| memset(node, 0, sizeof(*node)); |
| node->vm_files = RB_ROOT; |
| rwlock_init(&node->vm_lock); |
| } |
| |
| /** |
| * drm_vma_node_start() - Return start address for page-based addressing |
| * @node: Node to inspect |
| * |
| * Return the start address of the given node. This can be used as offset into |
| * the linear VM space that is provided by the VMA offset manager. Note that |
| * this can only be used for page-based addressing. If you need a proper offset |
| * for user-space mappings, you must apply "<< PAGE_SHIFT" or use the |
| * drm_vma_node_offset_addr() helper instead. |
| * |
| * RETURNS: |
| * Start address of @node for page-based addressing. 0 if the node does not |
| * have an offset allocated. |
| */ |
| static inline unsigned long drm_vma_node_start(struct drm_vma_offset_node *node) |
| { |
| return node->vm_node.start; |
| } |
| |
| /** |
| * drm_vma_node_size() - Return size (page-based) |
| * @node: Node to inspect |
| * |
| * Return the size as number of pages for the given node. This is the same size |
| * that was passed to drm_vma_offset_add(). If no offset is allocated for the |
| * node, this is 0. |
| * |
| * RETURNS: |
| * Size of @node as number of pages. 0 if the node does not have an offset |
| * allocated. |
| */ |
| static inline unsigned long drm_vma_node_size(struct drm_vma_offset_node *node) |
| { |
| return node->vm_node.size; |
| } |
| |
| /** |
| * drm_vma_node_offset_addr() - Return sanitized offset for user-space mmaps |
| * @node: Linked offset node |
| * |
| * Same as drm_vma_node_start() but returns the address as a valid offset that |
| * can be used for user-space mappings during mmap(). |
| * This must not be called on unlinked nodes. |
| * |
| * RETURNS: |
| * Offset of @node for byte-based addressing. 0 if the node does not have an |
| * object allocated. |
| */ |
| static inline __u64 drm_vma_node_offset_addr(struct drm_vma_offset_node *node) |
| { |
| return ((__u64)node->vm_node.start) << PAGE_SHIFT; |
| } |
| |
| /** |
| * drm_vma_node_unmap() - Unmap offset node |
| * @node: Offset node |
| * @file_mapping: Address space to unmap @node from |
| * |
| * Unmap all userspace mappings for a given offset node. The mappings must be |
| * associated with the @file_mapping address-space. If no offset exists |
| * nothing is done. |
| * |
| * This call is unlocked. The caller must guarantee that drm_vma_offset_remove() |
| * is not called on this node concurrently. |
| */ |
| static inline void drm_vma_node_unmap(struct drm_vma_offset_node *node, |
| struct address_space *file_mapping) |
| { |
| if (drm_mm_node_allocated(&node->vm_node)) |
| unmap_mapping_range(file_mapping, |
| drm_vma_node_offset_addr(node), |
| drm_vma_node_size(node) << PAGE_SHIFT, 1); |
| } |
| |
| /** |
| * drm_vma_node_verify_access() - Access verification helper for TTM |
| * @node: Offset node |
| * @tag: Tag of file to check |
| * |
| * This checks whether @tag is granted access to @node. It is the same as |
| * drm_vma_node_is_allowed() but suitable as drop-in helper for TTM |
| * verify_access() callbacks. |
| * |
| * RETURNS: |
| * 0 if access is granted, -EACCES otherwise. |
| */ |
| static inline int drm_vma_node_verify_access(struct drm_vma_offset_node *node, |
| struct drm_file *tag) |
| { |
| return drm_vma_node_is_allowed(node, tag) ? 0 : -EACCES; |
| } |
| |
| #endif /* __DRM_VMA_MANAGER_H__ */ |