mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-06 02:24:14 +08:00
0500c04ea1
The use of the drmP.h header file is deprecated. Remove use from all files in drm/* so people do not look there and follow a bad example. Build tested allyesconfig,allmodconfig on x86, arm etc. Including alpha that is as always more challenging than the rest. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Acked-by: Daniel Vetter <daniel@ffwll.ch> Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com> Cc: Maxime Ripard <maxime.ripard@bootlin.com> Cc: Sean Paul <sean@poorly.run> Cc: David Airlie <airlied@linux.ie> Link: https://patchwork.freedesktop.org/patch/msgid/20190526173535.32701-8-sam@ravnborg.org
390 lines
12 KiB
C
390 lines
12 KiB
C
// SPDX-License-Identifier: GPL-2.0 OR MIT
|
|
/*
|
|
* Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
|
|
* Copyright (c) 2012 David Airlie <airlied@linux.ie>
|
|
* 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 <linux/mm.h>
|
|
#include <linux/module.h>
|
|
#include <linux/rbtree.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/types.h>
|
|
|
|
#include <drm/drm_mm.h>
|
|
#include <drm/drm_vma_manager.h>
|
|
|
|
/**
|
|
* DOC: vma offset manager
|
|
*
|
|
* The vma-manager is responsible to map arbitrary driver-dependent memory
|
|
* regions into the linear user address-space. It provides offsets to the
|
|
* caller which can then be used on the address_space of the drm-device. It
|
|
* takes care to not overlap regions, size them appropriately and to not
|
|
* confuse mm-core by inconsistent fake vm_pgoff fields.
|
|
* Drivers shouldn't use this for object placement in VMEM. This manager should
|
|
* only be used to manage mappings into linear user-space VMs.
|
|
*
|
|
* We use drm_mm as backend to manage object allocations. But it is highly
|
|
* optimized for alloc/free calls, not lookups. Hence, we use an rb-tree to
|
|
* speed up offset lookups.
|
|
*
|
|
* You must not use multiple offset managers on a single address_space.
|
|
* Otherwise, mm-core will be unable to tear down memory mappings as the VM will
|
|
* no longer be linear.
|
|
*
|
|
* This offset manager works on page-based addresses. That is, every argument
|
|
* and return code (with the exception of drm_vma_node_offset_addr()) is given
|
|
* in number of pages, not number of bytes. That means, object sizes and offsets
|
|
* must always be page-aligned (as usual).
|
|
* If you want to get a valid byte-based user-space address for a given offset,
|
|
* please see drm_vma_node_offset_addr().
|
|
*
|
|
* Additionally to offset management, the vma offset manager also handles access
|
|
* management. For every open-file context that is allowed to access a given
|
|
* node, you must call drm_vma_node_allow(). Otherwise, an mmap() call on this
|
|
* open-file with the offset of the node will fail with -EACCES. To revoke
|
|
* access again, use drm_vma_node_revoke(). However, the caller is responsible
|
|
* for destroying already existing mappings, if required.
|
|
*/
|
|
|
|
/**
|
|
* drm_vma_offset_manager_init - Initialize new offset-manager
|
|
* @mgr: Manager object
|
|
* @page_offset: Offset of available memory area (page-based)
|
|
* @size: Size of available address space range (page-based)
|
|
*
|
|
* Initialize a new offset-manager. The offset and area size available for the
|
|
* manager are given as @page_offset and @size. Both are interpreted as
|
|
* page-numbers, not bytes.
|
|
*
|
|
* Adding/removing nodes from the manager is locked internally and protected
|
|
* against concurrent access. However, node allocation and destruction is left
|
|
* for the caller. While calling into the vma-manager, a given node must
|
|
* always be guaranteed to be referenced.
|
|
*/
|
|
void drm_vma_offset_manager_init(struct drm_vma_offset_manager *mgr,
|
|
unsigned long page_offset, unsigned long size)
|
|
{
|
|
rwlock_init(&mgr->vm_lock);
|
|
drm_mm_init(&mgr->vm_addr_space_mm, page_offset, size);
|
|
}
|
|
EXPORT_SYMBOL(drm_vma_offset_manager_init);
|
|
|
|
/**
|
|
* drm_vma_offset_manager_destroy() - Destroy offset manager
|
|
* @mgr: Manager object
|
|
*
|
|
* Destroy an object manager which was previously created via
|
|
* drm_vma_offset_manager_init(). The caller must remove all allocated nodes
|
|
* before destroying the manager. Otherwise, drm_mm will refuse to free the
|
|
* requested resources.
|
|
*
|
|
* The manager must not be accessed after this function is called.
|
|
*/
|
|
void drm_vma_offset_manager_destroy(struct drm_vma_offset_manager *mgr)
|
|
{
|
|
drm_mm_takedown(&mgr->vm_addr_space_mm);
|
|
}
|
|
EXPORT_SYMBOL(drm_vma_offset_manager_destroy);
|
|
|
|
/**
|
|
* drm_vma_offset_lookup_locked() - Find node in offset space
|
|
* @mgr: Manager object
|
|
* @start: Start address for object (page-based)
|
|
* @pages: Size of object (page-based)
|
|
*
|
|
* Find a node given a start address and object size. This returns the _best_
|
|
* match for the given node. That is, @start may point somewhere into a valid
|
|
* region and the given node will be returned, as long as the node spans the
|
|
* whole requested area (given the size in number of pages as @pages).
|
|
*
|
|
* Note that before lookup the vma offset manager lookup lock must be acquired
|
|
* with drm_vma_offset_lock_lookup(). See there for an example. This can then be
|
|
* used to implement weakly referenced lookups using kref_get_unless_zero().
|
|
*
|
|
* Example:
|
|
*
|
|
* ::
|
|
*
|
|
* drm_vma_offset_lock_lookup(mgr);
|
|
* node = drm_vma_offset_lookup_locked(mgr);
|
|
* if (node)
|
|
* kref_get_unless_zero(container_of(node, sth, entr));
|
|
* drm_vma_offset_unlock_lookup(mgr);
|
|
*
|
|
* RETURNS:
|
|
* Returns NULL if no suitable node can be found. Otherwise, the best match
|
|
* is returned. It's the caller's responsibility to make sure the node doesn't
|
|
* get destroyed before the caller can access it.
|
|
*/
|
|
struct drm_vma_offset_node *drm_vma_offset_lookup_locked(struct drm_vma_offset_manager *mgr,
|
|
unsigned long start,
|
|
unsigned long pages)
|
|
{
|
|
struct drm_mm_node *node, *best;
|
|
struct rb_node *iter;
|
|
unsigned long offset;
|
|
|
|
iter = mgr->vm_addr_space_mm.interval_tree.rb_root.rb_node;
|
|
best = NULL;
|
|
|
|
while (likely(iter)) {
|
|
node = rb_entry(iter, struct drm_mm_node, rb);
|
|
offset = node->start;
|
|
if (start >= offset) {
|
|
iter = iter->rb_right;
|
|
best = node;
|
|
if (start == offset)
|
|
break;
|
|
} else {
|
|
iter = iter->rb_left;
|
|
}
|
|
}
|
|
|
|
/* verify that the node spans the requested area */
|
|
if (best) {
|
|
offset = best->start + best->size;
|
|
if (offset < start + pages)
|
|
best = NULL;
|
|
}
|
|
|
|
if (!best)
|
|
return NULL;
|
|
|
|
return container_of(best, struct drm_vma_offset_node, vm_node);
|
|
}
|
|
EXPORT_SYMBOL(drm_vma_offset_lookup_locked);
|
|
|
|
/**
|
|
* drm_vma_offset_add() - Add offset node to manager
|
|
* @mgr: Manager object
|
|
* @node: Node to be added
|
|
* @pages: Allocation size visible to user-space (in number of pages)
|
|
*
|
|
* Add a node to the offset-manager. If the node was already added, this does
|
|
* nothing and return 0. @pages is the size of the object given in number of
|
|
* pages.
|
|
* After this call succeeds, you can access the offset of the node until it
|
|
* is removed again.
|
|
*
|
|
* If this call fails, it is safe to retry the operation or call
|
|
* drm_vma_offset_remove(), anyway. However, no cleanup is required in that
|
|
* case.
|
|
*
|
|
* @pages is not required to be the same size as the underlying memory object
|
|
* that you want to map. It only limits the size that user-space can map into
|
|
* their address space.
|
|
*
|
|
* RETURNS:
|
|
* 0 on success, negative error code on failure.
|
|
*/
|
|
int drm_vma_offset_add(struct drm_vma_offset_manager *mgr,
|
|
struct drm_vma_offset_node *node, unsigned long pages)
|
|
{
|
|
int ret = 0;
|
|
|
|
write_lock(&mgr->vm_lock);
|
|
|
|
if (!drm_mm_node_allocated(&node->vm_node))
|
|
ret = drm_mm_insert_node(&mgr->vm_addr_space_mm,
|
|
&node->vm_node, pages);
|
|
|
|
write_unlock(&mgr->vm_lock);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(drm_vma_offset_add);
|
|
|
|
/**
|
|
* drm_vma_offset_remove() - Remove offset node from manager
|
|
* @mgr: Manager object
|
|
* @node: Node to be removed
|
|
*
|
|
* Remove a node from the offset manager. If the node wasn't added before, this
|
|
* does nothing. After this call returns, the offset and size will be 0 until a
|
|
* new offset is allocated via drm_vma_offset_add() again. Helper functions like
|
|
* drm_vma_node_start() and drm_vma_node_offset_addr() will return 0 if no
|
|
* offset is allocated.
|
|
*/
|
|
void drm_vma_offset_remove(struct drm_vma_offset_manager *mgr,
|
|
struct drm_vma_offset_node *node)
|
|
{
|
|
write_lock(&mgr->vm_lock);
|
|
|
|
if (drm_mm_node_allocated(&node->vm_node)) {
|
|
drm_mm_remove_node(&node->vm_node);
|
|
memset(&node->vm_node, 0, sizeof(node->vm_node));
|
|
}
|
|
|
|
write_unlock(&mgr->vm_lock);
|
|
}
|
|
EXPORT_SYMBOL(drm_vma_offset_remove);
|
|
|
|
/**
|
|
* drm_vma_node_allow - Add open-file to list of allowed users
|
|
* @node: Node to modify
|
|
* @tag: Tag of file to remove
|
|
*
|
|
* Add @tag to the list of allowed open-files for this node. If @tag is
|
|
* already on this list, the ref-count is incremented.
|
|
*
|
|
* The list of allowed-users is preserved across drm_vma_offset_add() and
|
|
* drm_vma_offset_remove() calls. You may even call it if the node is currently
|
|
* not added to any offset-manager.
|
|
*
|
|
* You must remove all open-files the same number of times as you added them
|
|
* before destroying the node. Otherwise, you will leak memory.
|
|
*
|
|
* This is locked against concurrent access internally.
|
|
*
|
|
* RETURNS:
|
|
* 0 on success, negative error code on internal failure (out-of-mem)
|
|
*/
|
|
int drm_vma_node_allow(struct drm_vma_offset_node *node, struct drm_file *tag)
|
|
{
|
|
struct rb_node **iter;
|
|
struct rb_node *parent = NULL;
|
|
struct drm_vma_offset_file *new, *entry;
|
|
int ret = 0;
|
|
|
|
/* Preallocate entry to avoid atomic allocations below. It is quite
|
|
* unlikely that an open-file is added twice to a single node so we
|
|
* don't optimize for this case. OOM is checked below only if the entry
|
|
* is actually used. */
|
|
new = kmalloc(sizeof(*entry), GFP_KERNEL);
|
|
|
|
write_lock(&node->vm_lock);
|
|
|
|
iter = &node->vm_files.rb_node;
|
|
|
|
while (likely(*iter)) {
|
|
parent = *iter;
|
|
entry = rb_entry(*iter, struct drm_vma_offset_file, vm_rb);
|
|
|
|
if (tag == entry->vm_tag) {
|
|
entry->vm_count++;
|
|
goto unlock;
|
|
} else if (tag > entry->vm_tag) {
|
|
iter = &(*iter)->rb_right;
|
|
} else {
|
|
iter = &(*iter)->rb_left;
|
|
}
|
|
}
|
|
|
|
if (!new) {
|
|
ret = -ENOMEM;
|
|
goto unlock;
|
|
}
|
|
|
|
new->vm_tag = tag;
|
|
new->vm_count = 1;
|
|
rb_link_node(&new->vm_rb, parent, iter);
|
|
rb_insert_color(&new->vm_rb, &node->vm_files);
|
|
new = NULL;
|
|
|
|
unlock:
|
|
write_unlock(&node->vm_lock);
|
|
kfree(new);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(drm_vma_node_allow);
|
|
|
|
/**
|
|
* drm_vma_node_revoke - Remove open-file from list of allowed users
|
|
* @node: Node to modify
|
|
* @tag: Tag of file to remove
|
|
*
|
|
* Decrement the ref-count of @tag in the list of allowed open-files on @node.
|
|
* If the ref-count drops to zero, remove @tag from the list. You must call
|
|
* this once for every drm_vma_node_allow() on @tag.
|
|
*
|
|
* This is locked against concurrent access internally.
|
|
*
|
|
* If @tag is not on the list, nothing is done.
|
|
*/
|
|
void drm_vma_node_revoke(struct drm_vma_offset_node *node,
|
|
struct drm_file *tag)
|
|
{
|
|
struct drm_vma_offset_file *entry;
|
|
struct rb_node *iter;
|
|
|
|
write_lock(&node->vm_lock);
|
|
|
|
iter = node->vm_files.rb_node;
|
|
while (likely(iter)) {
|
|
entry = rb_entry(iter, struct drm_vma_offset_file, vm_rb);
|
|
if (tag == entry->vm_tag) {
|
|
if (!--entry->vm_count) {
|
|
rb_erase(&entry->vm_rb, &node->vm_files);
|
|
kfree(entry);
|
|
}
|
|
break;
|
|
} else if (tag > entry->vm_tag) {
|
|
iter = iter->rb_right;
|
|
} else {
|
|
iter = iter->rb_left;
|
|
}
|
|
}
|
|
|
|
write_unlock(&node->vm_lock);
|
|
}
|
|
EXPORT_SYMBOL(drm_vma_node_revoke);
|
|
|
|
/**
|
|
* drm_vma_node_is_allowed - Check whether an open-file is granted access
|
|
* @node: Node to check
|
|
* @tag: Tag of file to remove
|
|
*
|
|
* Search the list in @node whether @tag is currently on the list of allowed
|
|
* open-files (see drm_vma_node_allow()).
|
|
*
|
|
* This is locked against concurrent access internally.
|
|
*
|
|
* RETURNS:
|
|
* true iff @filp is on the list
|
|
*/
|
|
bool drm_vma_node_is_allowed(struct drm_vma_offset_node *node,
|
|
struct drm_file *tag)
|
|
{
|
|
struct drm_vma_offset_file *entry;
|
|
struct rb_node *iter;
|
|
|
|
read_lock(&node->vm_lock);
|
|
|
|
iter = node->vm_files.rb_node;
|
|
while (likely(iter)) {
|
|
entry = rb_entry(iter, struct drm_vma_offset_file, vm_rb);
|
|
if (tag == entry->vm_tag)
|
|
break;
|
|
else if (tag > entry->vm_tag)
|
|
iter = iter->rb_right;
|
|
else
|
|
iter = iter->rb_left;
|
|
}
|
|
|
|
read_unlock(&node->vm_lock);
|
|
|
|
return iter;
|
|
}
|
|
EXPORT_SYMBOL(drm_vma_node_is_allowed);
|