1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* psb GEM interface
*
* Copyright (c) 2011, Intel Corporation.
*
* Authors: Alan Cox
*
* TODO:
* - we need to work out if the MMU is relevant (eg for
* accelerated operations on a GEM object)
*/
#include <linux/pagemap.h>
#include <drm/drm.h>
#include <drm/drm_vma_manager.h>
#include "gem.h"
#include "psb_drv.h"
static vm_fault_t psb_gem_fault(struct vm_fault *vmf);
static void psb_gem_free_object(struct drm_gem_object *obj)
{
struct gtt_range *gtt = container_of(obj, struct gtt_range, gem);
/* Remove the list map if one is present */
drm_gem_free_mmap_offset(obj);
drm_gem_object_release(obj);
/* This must occur last as it frees up the memory of the GEM object */
psb_gtt_free_range(obj->dev, gtt);
}
static const struct vm_operations_struct psb_gem_vm_ops = {
.fault = psb_gem_fault,
.open = drm_gem_vm_open,
.close = drm_gem_vm_close,
};
const struct drm_gem_object_funcs psb_gem_object_funcs = {
.free = psb_gem_free_object,
.vm_ops = &psb_gem_vm_ops,
};
/**
* psb_gem_create - create a mappable object
* @file: the DRM file of the client
* @dev: our device
* @size: the size requested
* @handlep: returned handle (opaque number)
* @stolen: unused
* @align: unused
*
* Create a GEM object, fill in the boilerplate and attach a handle to
* it so that userspace can speak about it. This does the core work
* for the various methods that do/will create GEM objects for things
*/
int psb_gem_create(struct drm_file *file, struct drm_device *dev, u64 size,
u32 *handlep, int stolen, u32 align)
{
struct gtt_range *r;
int ret;
u32 handle;
size = roundup(size, PAGE_SIZE);
/* Allocate our object - for now a direct gtt range which is not
stolen memory backed */
r = psb_gtt_alloc_range(dev, size, "gem", 0, PAGE_SIZE);
if (r == NULL) {
dev_err(dev->dev, "no memory for %lld byte GEM object\n", size);
return -ENOSPC;
}
r->gem.funcs = &psb_gem_object_funcs;
/* Initialize the extra goodies GEM needs to do all the hard work */
if (drm_gem_object_init(dev, &r->gem, size) != 0) {
psb_gtt_free_range(dev, r);
/* GEM doesn't give an error code so use -ENOMEM */
dev_err(dev->dev, "GEM init failed for %lld\n", size);
return -ENOMEM;
}
/* Limit the object to 32bit mappings */
mapping_set_gfp_mask(r->gem.filp->f_mapping, GFP_KERNEL | __GFP_DMA32);
/* Give the object a handle so we can carry it more easily */
ret = drm_gem_handle_create(file, &r->gem, &handle);
if (ret) {
dev_err(dev->dev, "GEM handle failed for %p, %lld\n",
&r->gem, size);
drm_gem_object_release(&r->gem);
psb_gtt_free_range(dev, r);
return ret;
}
/* We have the initial and handle reference but need only one now */
drm_gem_object_put(&r->gem);
*handlep = handle;
return 0;
}
/**
* psb_gem_dumb_create - create a dumb buffer
* @file: our client file
* @dev: our device
* @args: the requested arguments copied from userspace
*
* Allocate a buffer suitable for use for a frame buffer of the
* form described by user space. Give userspace a handle by which
* to reference it.
*/
int psb_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
struct drm_mode_create_dumb *args)
{
args->pitch = ALIGN(args->width * ((args->bpp + 7) / 8), 64);
args->size = args->pitch * args->height;
return psb_gem_create(file, dev, args->size, &args->handle, 0,
PAGE_SIZE);
}
/**
* psb_gem_fault - pagefault handler for GEM objects
* @vmf: fault detail
*
* Invoked when a fault occurs on an mmap of a GEM managed area. GEM
* does most of the work for us including the actual map/unmap calls
* but we need to do the actual page work.
*
* This code eventually needs to handle faulting objects in and out
* of the GTT and repacking it when we run out of space. We can put
* that off for now and for our simple uses
*
* The VMA was set up by GEM. In doing so it also ensured that the
* vma->vm_private_data points to the GEM object that is backing this
* mapping.
*/
static vm_fault_t psb_gem_fault(struct vm_fault *vmf)
{
struct vm_area_struct *vma = vmf->vma;
struct drm_gem_object *obj;
struct gtt_range *r;
int err;
vm_fault_t ret;
unsigned long pfn;
pgoff_t page_offset;
struct drm_device *dev;
struct drm_psb_private *dev_priv;
obj = vma->vm_private_data; /* GEM object */
dev = obj->dev;
dev_priv = dev->dev_private;
r = container_of(obj, struct gtt_range, gem); /* Get the gtt range */
/* Make sure we don't parallel update on a fault, nor move or remove
something from beneath our feet */
mutex_lock(&dev_priv->mmap_mutex);
/* For now the mmap pins the object and it stays pinned. As things
stand that will do us no harm */
if (r->mmapping == 0) {
err = psb_gtt_pin(r);
if (err < 0) {
dev_err(dev->dev, "gma500: pin failed: %d\n", err);
ret = vmf_error(err);
goto fail;
}
r->mmapping = 1;
}
/* Page relative to the VMA start - we must calculate this ourselves
because vmf->pgoff is the fake GEM offset */
page_offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
/* CPU view of the page, don't go via the GART for CPU writes */
if (r->stolen)
pfn = (dev_priv->stolen_base + r->offset) >> PAGE_SHIFT;
else
pfn = page_to_pfn(r->pages[page_offset]);
ret = vmf_insert_pfn(vma, vmf->address, pfn);
fail:
mutex_unlock(&dev_priv->mmap_mutex);
return ret;
}
|
