linux_dsm_epyc7002/drivers/gpu/drm/drm_gem.c
David Herrmann 89c8233f82 drm/gem: simplify object initialization
drm_gem_object_init() and drm_gem_private_object_init() do exactly the
same (except for shmem alloc) so make the first use the latter to reduce
code duplication.

Also drop the return code from drm_gem_private_object_init(). It seems
unlikely that we will extend it any time soon so no reason to keep it
around. This simplifies code paths in drivers, too.

Last but not least, fix gma500 to call drm_gem_object_release() before
freeing objects that were allocated via drm_gem_private_object_init().
That isn't actually necessary for now, but might be in the future.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Acked-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@gmail.com>
2013-07-23 19:37:53 +10:00

735 lines
19 KiB
C

/*
* Copyright © 2008 Intel Corporation
*
* 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 (including the next
* paragraph) 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 AUTHORS OR COPYRIGHT HOLDERS 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.
*
* Authors:
* Eric Anholt <eric@anholt.net>
*
*/
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/uaccess.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/module.h>
#include <linux/mman.h>
#include <linux/pagemap.h>
#include <linux/shmem_fs.h>
#include <linux/dma-buf.h>
#include <drm/drmP.h>
/** @file drm_gem.c
*
* This file provides some of the base ioctls and library routines for
* the graphics memory manager implemented by each device driver.
*
* Because various devices have different requirements in terms of
* synchronization and migration strategies, implementing that is left up to
* the driver, and all that the general API provides should be generic --
* allocating objects, reading/writing data with the cpu, freeing objects.
* Even there, platform-dependent optimizations for reading/writing data with
* the CPU mean we'll likely hook those out to driver-specific calls. However,
* the DRI2 implementation wants to have at least allocate/mmap be generic.
*
* The goal was to have swap-backed object allocation managed through
* struct file. However, file descriptors as handles to a struct file have
* two major failings:
* - Process limits prevent more than 1024 or so being used at a time by
* default.
* - Inability to allocate high fds will aggravate the X Server's select()
* handling, and likely that of many GL client applications as well.
*
* This led to a plan of using our own integer IDs (called handles, following
* DRM terminology) to mimic fds, and implement the fd syscalls we need as
* ioctls. The objects themselves will still include the struct file so
* that we can transition to fds if the required kernel infrastructure shows
* up at a later date, and as our interface with shmfs for memory allocation.
*/
/*
* 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) * 16)
#else
#define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFUL >> PAGE_SHIFT) + 1)
#define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFUL >> PAGE_SHIFT) * 16)
#endif
/**
* Initialize the GEM device fields
*/
int
drm_gem_init(struct drm_device *dev)
{
struct drm_gem_mm *mm;
spin_lock_init(&dev->object_name_lock);
idr_init(&dev->object_name_idr);
mm = kzalloc(sizeof(struct drm_gem_mm), GFP_KERNEL);
if (!mm) {
DRM_ERROR("out of memory\n");
return -ENOMEM;
}
dev->mm_private = mm;
if (drm_ht_create(&mm->offset_hash, 12)) {
kfree(mm);
return -ENOMEM;
}
drm_mm_init(&mm->offset_manager, DRM_FILE_PAGE_OFFSET_START,
DRM_FILE_PAGE_OFFSET_SIZE);
return 0;
}
void
drm_gem_destroy(struct drm_device *dev)
{
struct drm_gem_mm *mm = dev->mm_private;
drm_mm_takedown(&mm->offset_manager);
drm_ht_remove(&mm->offset_hash);
kfree(mm);
dev->mm_private = NULL;
}
/**
* Initialize an already allocated GEM object of the specified size with
* shmfs backing store.
*/
int drm_gem_object_init(struct drm_device *dev,
struct drm_gem_object *obj, size_t size)
{
struct file *filp;
filp = shmem_file_setup("drm mm object", size, VM_NORESERVE);
if (IS_ERR(filp))
return PTR_ERR(filp);
drm_gem_private_object_init(dev, obj, size);
obj->filp = filp;
return 0;
}
EXPORT_SYMBOL(drm_gem_object_init);
/**
* Initialize an already allocated GEM object of the specified size with
* no GEM provided backing store. Instead the caller is responsible for
* backing the object and handling it.
*/
void drm_gem_private_object_init(struct drm_device *dev,
struct drm_gem_object *obj, size_t size)
{
BUG_ON((size & (PAGE_SIZE - 1)) != 0);
obj->dev = dev;
obj->filp = NULL;
kref_init(&obj->refcount);
atomic_set(&obj->handle_count, 0);
obj->size = size;
}
EXPORT_SYMBOL(drm_gem_private_object_init);
/**
* Allocate a GEM object of the specified size with shmfs backing store
*/
struct drm_gem_object *
drm_gem_object_alloc(struct drm_device *dev, size_t size)
{
struct drm_gem_object *obj;
obj = kzalloc(sizeof(*obj), GFP_KERNEL);
if (!obj)
goto free;
if (drm_gem_object_init(dev, obj, size) != 0)
goto free;
if (dev->driver->gem_init_object != NULL &&
dev->driver->gem_init_object(obj) != 0) {
goto fput;
}
return obj;
fput:
/* Object_init mangles the global counters - readjust them. */
fput(obj->filp);
free:
kfree(obj);
return NULL;
}
EXPORT_SYMBOL(drm_gem_object_alloc);
static void
drm_gem_remove_prime_handles(struct drm_gem_object *obj, struct drm_file *filp)
{
if (obj->import_attach) {
drm_prime_remove_buf_handle(&filp->prime,
obj->import_attach->dmabuf);
}
if (obj->export_dma_buf) {
drm_prime_remove_buf_handle(&filp->prime,
obj->export_dma_buf);
}
}
/**
* Removes the mapping from handle to filp for this object.
*/
int
drm_gem_handle_delete(struct drm_file *filp, u32 handle)
{
struct drm_device *dev;
struct drm_gem_object *obj;
/* This is gross. The idr system doesn't let us try a delete and
* return an error code. It just spews if you fail at deleting.
* So, we have to grab a lock around finding the object and then
* doing the delete on it and dropping the refcount, or the user
* could race us to double-decrement the refcount and cause a
* use-after-free later. Given the frequency of our handle lookups,
* we may want to use ida for number allocation and a hash table
* for the pointers, anyway.
*/
spin_lock(&filp->table_lock);
/* Check if we currently have a reference on the object */
obj = idr_find(&filp->object_idr, handle);
if (obj == NULL) {
spin_unlock(&filp->table_lock);
return -EINVAL;
}
dev = obj->dev;
/* Release reference and decrement refcount. */
idr_remove(&filp->object_idr, handle);
spin_unlock(&filp->table_lock);
drm_gem_remove_prime_handles(obj, filp);
if (dev->driver->gem_close_object)
dev->driver->gem_close_object(obj, filp);
drm_gem_object_handle_unreference_unlocked(obj);
return 0;
}
EXPORT_SYMBOL(drm_gem_handle_delete);
/**
* Create a handle for this object. This adds a handle reference
* to the object, which includes a regular reference count. Callers
* will likely want to dereference the object afterwards.
*/
int
drm_gem_handle_create(struct drm_file *file_priv,
struct drm_gem_object *obj,
u32 *handlep)
{
struct drm_device *dev = obj->dev;
int ret;
/*
* Get the user-visible handle using idr. Preload and perform
* allocation under our spinlock.
*/
idr_preload(GFP_KERNEL);
spin_lock(&file_priv->table_lock);
ret = idr_alloc(&file_priv->object_idr, obj, 1, 0, GFP_NOWAIT);
spin_unlock(&file_priv->table_lock);
idr_preload_end();
if (ret < 0)
return ret;
*handlep = ret;
drm_gem_object_handle_reference(obj);
if (dev->driver->gem_open_object) {
ret = dev->driver->gem_open_object(obj, file_priv);
if (ret) {
drm_gem_handle_delete(file_priv, *handlep);
return ret;
}
}
return 0;
}
EXPORT_SYMBOL(drm_gem_handle_create);
/**
* drm_gem_free_mmap_offset - release a fake mmap offset for an object
* @obj: obj in question
*
* This routine frees fake offsets allocated by drm_gem_create_mmap_offset().
*/
void
drm_gem_free_mmap_offset(struct drm_gem_object *obj)
{
struct drm_device *dev = obj->dev;
struct drm_gem_mm *mm = dev->mm_private;
struct drm_map_list *list = &obj->map_list;
drm_ht_remove_item(&mm->offset_hash, &list->hash);
drm_mm_put_block(list->file_offset_node);
kfree(list->map);
list->map = NULL;
}
EXPORT_SYMBOL(drm_gem_free_mmap_offset);
/**
* drm_gem_create_mmap_offset - create a fake mmap offset for an object
* @obj: obj in question
*
* GEM memory mapping works by handing back to userspace a fake mmap offset
* it can use in a subsequent mmap(2) call. The DRM core code then looks
* up the object based on the offset and sets up the various memory mapping
* structures.
*
* This routine allocates and attaches a fake offset for @obj.
*/
int
drm_gem_create_mmap_offset(struct drm_gem_object *obj)
{
struct drm_device *dev = obj->dev;
struct drm_gem_mm *mm = dev->mm_private;
struct drm_map_list *list;
struct drm_local_map *map;
int ret;
/* Set the object up for mmap'ing */
list = &obj->map_list;
list->map = kzalloc(sizeof(struct drm_map_list), GFP_KERNEL);
if (!list->map)
return -ENOMEM;
map = list->map;
map->type = _DRM_GEM;
map->size = obj->size;
map->handle = obj;
/* Get a DRM GEM mmap offset allocated... */
list->file_offset_node = drm_mm_search_free(&mm->offset_manager,
obj->size / PAGE_SIZE, 0, false);
if (!list->file_offset_node) {
DRM_ERROR("failed to allocate offset for bo %d\n", obj->name);
ret = -ENOSPC;
goto out_free_list;
}
list->file_offset_node = drm_mm_get_block(list->file_offset_node,
obj->size / PAGE_SIZE, 0);
if (!list->file_offset_node) {
ret = -ENOMEM;
goto out_free_list;
}
list->hash.key = list->file_offset_node->start;
ret = drm_ht_insert_item(&mm->offset_hash, &list->hash);
if (ret) {
DRM_ERROR("failed to add to map hash\n");
goto out_free_mm;
}
return 0;
out_free_mm:
drm_mm_put_block(list->file_offset_node);
out_free_list:
kfree(list->map);
list->map = NULL;
return ret;
}
EXPORT_SYMBOL(drm_gem_create_mmap_offset);
/** Returns a reference to the object named by the handle. */
struct drm_gem_object *
drm_gem_object_lookup(struct drm_device *dev, struct drm_file *filp,
u32 handle)
{
struct drm_gem_object *obj;
spin_lock(&filp->table_lock);
/* Check if we currently have a reference on the object */
obj = idr_find(&filp->object_idr, handle);
if (obj == NULL) {
spin_unlock(&filp->table_lock);
return NULL;
}
drm_gem_object_reference(obj);
spin_unlock(&filp->table_lock);
return obj;
}
EXPORT_SYMBOL(drm_gem_object_lookup);
/**
* Releases the handle to an mm object.
*/
int
drm_gem_close_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_gem_close *args = data;
int ret;
if (!(dev->driver->driver_features & DRIVER_GEM))
return -ENODEV;
ret = drm_gem_handle_delete(file_priv, args->handle);
return ret;
}
/**
* Create a global name for an object, returning the name.
*
* Note that the name does not hold a reference; when the object
* is freed, the name goes away.
*/
int
drm_gem_flink_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_gem_flink *args = data;
struct drm_gem_object *obj;
int ret;
if (!(dev->driver->driver_features & DRIVER_GEM))
return -ENODEV;
obj = drm_gem_object_lookup(dev, file_priv, args->handle);
if (obj == NULL)
return -ENOENT;
idr_preload(GFP_KERNEL);
spin_lock(&dev->object_name_lock);
if (!obj->name) {
ret = idr_alloc(&dev->object_name_idr, obj, 1, 0, GFP_NOWAIT);
if (ret < 0)
goto err;
obj->name = ret;
/* Allocate a reference for the name table. */
drm_gem_object_reference(obj);
}
args->name = (uint64_t) obj->name;
ret = 0;
err:
spin_unlock(&dev->object_name_lock);
idr_preload_end();
drm_gem_object_unreference_unlocked(obj);
return ret;
}
/**
* Open an object using the global name, returning a handle and the size.
*
* This handle (of course) holds a reference to the object, so the object
* will not go away until the handle is deleted.
*/
int
drm_gem_open_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_gem_open *args = data;
struct drm_gem_object *obj;
int ret;
u32 handle;
if (!(dev->driver->driver_features & DRIVER_GEM))
return -ENODEV;
spin_lock(&dev->object_name_lock);
obj = idr_find(&dev->object_name_idr, (int) args->name);
if (obj)
drm_gem_object_reference(obj);
spin_unlock(&dev->object_name_lock);
if (!obj)
return -ENOENT;
ret = drm_gem_handle_create(file_priv, obj, &handle);
drm_gem_object_unreference_unlocked(obj);
if (ret)
return ret;
args->handle = handle;
args->size = obj->size;
return 0;
}
/**
* Called at device open time, sets up the structure for handling refcounting
* of mm objects.
*/
void
drm_gem_open(struct drm_device *dev, struct drm_file *file_private)
{
idr_init(&file_private->object_idr);
spin_lock_init(&file_private->table_lock);
}
/**
* Called at device close to release the file's
* handle references on objects.
*/
static int
drm_gem_object_release_handle(int id, void *ptr, void *data)
{
struct drm_file *file_priv = data;
struct drm_gem_object *obj = ptr;
struct drm_device *dev = obj->dev;
drm_gem_remove_prime_handles(obj, file_priv);
if (dev->driver->gem_close_object)
dev->driver->gem_close_object(obj, file_priv);
drm_gem_object_handle_unreference_unlocked(obj);
return 0;
}
/**
* Called at close time when the filp is going away.
*
* Releases any remaining references on objects by this filp.
*/
void
drm_gem_release(struct drm_device *dev, struct drm_file *file_private)
{
idr_for_each(&file_private->object_idr,
&drm_gem_object_release_handle, file_private);
idr_destroy(&file_private->object_idr);
}
void
drm_gem_object_release(struct drm_gem_object *obj)
{
if (obj->filp)
fput(obj->filp);
}
EXPORT_SYMBOL(drm_gem_object_release);
/**
* Called after the last reference to the object has been lost.
* Must be called holding struct_ mutex
*
* Frees the object
*/
void
drm_gem_object_free(struct kref *kref)
{
struct drm_gem_object *obj = (struct drm_gem_object *) kref;
struct drm_device *dev = obj->dev;
BUG_ON(!mutex_is_locked(&dev->struct_mutex));
if (dev->driver->gem_free_object != NULL)
dev->driver->gem_free_object(obj);
}
EXPORT_SYMBOL(drm_gem_object_free);
static void drm_gem_object_ref_bug(struct kref *list_kref)
{
BUG();
}
/**
* Called after the last handle to the object has been closed
*
* Removes any name for the object. Note that this must be
* called before drm_gem_object_free or we'll be touching
* freed memory
*/
void drm_gem_object_handle_free(struct drm_gem_object *obj)
{
struct drm_device *dev = obj->dev;
/* Remove any name for this object */
spin_lock(&dev->object_name_lock);
if (obj->name) {
idr_remove(&dev->object_name_idr, obj->name);
obj->name = 0;
spin_unlock(&dev->object_name_lock);
/*
* The object name held a reference to this object, drop
* that now.
*
* This cannot be the last reference, since the handle holds one too.
*/
kref_put(&obj->refcount, drm_gem_object_ref_bug);
} else
spin_unlock(&dev->object_name_lock);
}
EXPORT_SYMBOL(drm_gem_object_handle_free);
void drm_gem_vm_open(struct vm_area_struct *vma)
{
struct drm_gem_object *obj = vma->vm_private_data;
drm_gem_object_reference(obj);
mutex_lock(&obj->dev->struct_mutex);
drm_vm_open_locked(obj->dev, vma);
mutex_unlock(&obj->dev->struct_mutex);
}
EXPORT_SYMBOL(drm_gem_vm_open);
void drm_gem_vm_close(struct vm_area_struct *vma)
{
struct drm_gem_object *obj = vma->vm_private_data;
struct drm_device *dev = obj->dev;
mutex_lock(&dev->struct_mutex);
drm_vm_close_locked(obj->dev, vma);
drm_gem_object_unreference(obj);
mutex_unlock(&dev->struct_mutex);
}
EXPORT_SYMBOL(drm_gem_vm_close);
/**
* drm_gem_mmap_obj - memory map a GEM object
* @obj: the GEM object to map
* @obj_size: the object size to be mapped, in bytes
* @vma: VMA for the area to be mapped
*
* Set up the VMA to prepare mapping of the GEM object using the gem_vm_ops
* provided by the driver. Depending on their requirements, drivers can either
* provide a fault handler in their gem_vm_ops (in which case any accesses to
* the object will be trapped, to perform migration, GTT binding, surface
* register allocation, or performance monitoring), or mmap the buffer memory
* synchronously after calling drm_gem_mmap_obj.
*
* This function is mainly intended to implement the DMABUF mmap operation, when
* the GEM object is not looked up based on its fake offset. To implement the
* DRM mmap operation, drivers should use the drm_gem_mmap() function.
*
* NOTE: This function has to be protected with dev->struct_mutex
*
* Return 0 or success or -EINVAL if the object size is smaller than the VMA
* size, or if no gem_vm_ops are provided.
*/
int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
struct vm_area_struct *vma)
{
struct drm_device *dev = obj->dev;
lockdep_assert_held(&dev->struct_mutex);
/* Check for valid size. */
if (obj_size < vma->vm_end - vma->vm_start)
return -EINVAL;
if (!dev->driver->gem_vm_ops)
return -EINVAL;
vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
vma->vm_ops = dev->driver->gem_vm_ops;
vma->vm_private_data = obj;
vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
/* Take a ref for this mapping of the object, so that the fault
* handler can dereference the mmap offset's pointer to the object.
* This reference is cleaned up by the corresponding vm_close
* (which should happen whether the vma was created by this call, or
* by a vm_open due to mremap or partial unmap or whatever).
*/
drm_gem_object_reference(obj);
drm_vm_open_locked(dev, vma);
return 0;
}
EXPORT_SYMBOL(drm_gem_mmap_obj);
/**
* drm_gem_mmap - memory map routine for GEM objects
* @filp: DRM file pointer
* @vma: VMA for the area to be mapped
*
* If a driver supports GEM object mapping, mmap calls on the DRM file
* descriptor will end up here.
*
* Look up the GEM object based on the offset passed in (vma->vm_pgoff will
* contain the fake offset we created when the GTT map ioctl was called on
* the object) and map it with a call to drm_gem_mmap_obj().
*/
int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
{
struct drm_file *priv = filp->private_data;
struct drm_device *dev = priv->minor->dev;
struct drm_gem_mm *mm = dev->mm_private;
struct drm_local_map *map = NULL;
struct drm_hash_item *hash;
int ret = 0;
if (drm_device_is_unplugged(dev))
return -ENODEV;
mutex_lock(&dev->struct_mutex);
if (drm_ht_find_item(&mm->offset_hash, vma->vm_pgoff, &hash)) {
mutex_unlock(&dev->struct_mutex);
return drm_mmap(filp, vma);
}
map = drm_hash_entry(hash, struct drm_map_list, hash)->map;
if (!map ||
((map->flags & _DRM_RESTRICTED) && !capable(CAP_SYS_ADMIN))) {
ret = -EPERM;
goto out_unlock;
}
ret = drm_gem_mmap_obj(map->handle, map->size, vma);
out_unlock:
mutex_unlock(&dev->struct_mutex);
return ret;
}
EXPORT_SYMBOL(drm_gem_mmap);