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-rw-r--r--include/drm/drm_vma_manager.h246
1 files changed, 246 insertions, 0 deletions
diff --git a/include/drm/drm_vma_manager.h b/include/drm/drm_vma_manager.h
new file mode 100644
index 000000000..76ac5e97a
--- /dev/null
+++ b/include/drm/drm_vma_manager.h
@@ -0,0 +1,246 @@
+#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/rbtree.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+
+/* We make up offsets for buffer objects so we can recognize them at
+ * mmap time. pgoff in mmap is an unsigned long, so we need to make sure
+ * that the faked up offset will fit
+ */
+#if BITS_PER_LONG == 64
+#define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFFUL >> PAGE_SHIFT) + 1)
+#define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFFUL >> PAGE_SHIFT) * 256)
+#else
+#define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFUL >> PAGE_SHIFT) + 1)
+#define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFUL >> PAGE_SHIFT) * 16)
+#endif
+
+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(const 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__ */