1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2012 Russell King
5 #include <linux/dma-buf.h>
6 #include <linux/dma-mapping.h>
7 #include <linux/shmem_fs.h>
8 #include "armada_drm.h"
9 #include "armada_gem.h"
10 #include <drm/armada_drm.h>
11 #include "armada_ioctlP.h"
13 static vm_fault_t armada_gem_vm_fault(struct vm_fault *vmf)
15 struct drm_gem_object *gobj = vmf->vma->vm_private_data;
16 struct armada_gem_object *obj = drm_to_armada_gem(gobj);
17 unsigned long pfn = obj->phys_addr >> PAGE_SHIFT;
19 pfn += (vmf->address - vmf->vma->vm_start) >> PAGE_SHIFT;
20 return vmf_insert_pfn(vmf->vma, vmf->address, pfn);
23 const struct vm_operations_struct armada_gem_vm_ops = {
24 .fault = armada_gem_vm_fault,
25 .open = drm_gem_vm_open,
26 .close = drm_gem_vm_close,
29 static size_t roundup_gem_size(size_t size)
31 return roundup(size, PAGE_SIZE);
34 void armada_gem_free_object(struct drm_gem_object *obj)
36 struct armada_gem_object *dobj = drm_to_armada_gem(obj);
37 struct armada_private *priv = obj->dev->dev_private;
39 DRM_DEBUG_DRIVER("release obj %p\n", dobj);
41 drm_gem_free_mmap_offset(&dobj->obj);
43 might_lock(&priv->linear_lock);
46 /* page backed memory */
47 unsigned int order = get_order(dobj->obj.size);
48 __free_pages(dobj->page, order);
49 } else if (dobj->linear) {
50 /* linear backed memory */
51 mutex_lock(&priv->linear_lock);
52 drm_mm_remove_node(dobj->linear);
53 mutex_unlock(&priv->linear_lock);
59 if (dobj->obj.import_attach) {
60 /* We only ever display imported data */
62 dma_buf_unmap_attachment(dobj->obj.import_attach,
63 dobj->sgt, DMA_TO_DEVICE);
64 drm_prime_gem_destroy(&dobj->obj, NULL);
67 drm_gem_object_release(&dobj->obj);
73 armada_gem_linear_back(struct drm_device *dev, struct armada_gem_object *obj)
75 struct armada_private *priv = dev->dev_private;
76 size_t size = obj->obj.size;
78 if (obj->page || obj->linear)
82 * If it is a small allocation (typically cursor, which will
83 * be 32x64 or 64x32 ARGB pixels) try to get it from the system.
84 * Framebuffers will never be this small (our minimum size for
85 * framebuffers is larger than this anyway.) Such objects are
86 * only accessed by the CPU so we don't need any special handing
90 unsigned int order = get_order(size);
91 struct page *p = alloc_pages(GFP_KERNEL, order);
94 obj->addr = page_address(p);
95 obj->phys_addr = page_to_phys(p);
98 memset(obj->addr, 0, PAGE_ALIGN(size));
103 * We could grab something from CMA if it's enabled, but that
104 * involves building in a problem:
106 * CMA's interface uses dma_alloc_coherent(), which provides us
107 * with an CPU virtual address and a device address.
109 * The CPU virtual address may be either an address in the kernel
110 * direct mapped region (for example, as it would be on x86) or
111 * it may be remapped into another part of kernel memory space
112 * (eg, as it would be on ARM.) This means virt_to_phys() on the
113 * returned virtual address is invalid depending on the architecture
116 * The device address may also not be a physical address; it may
117 * be that there is some kind of remapping between the device and
118 * system RAM, which makes the use of the device address also
119 * unsafe to re-use as a physical address.
121 * This makes DRM usage of dma_alloc_coherent() in a generic way
122 * at best very questionable and unsafe.
125 /* Otherwise, grab it from our linear allocation */
127 struct drm_mm_node *node;
128 unsigned align = min_t(unsigned, size, SZ_2M);
132 node = kzalloc(sizeof(*node), GFP_KERNEL);
136 mutex_lock(&priv->linear_lock);
137 ret = drm_mm_insert_node_generic(&priv->linear, node,
139 mutex_unlock(&priv->linear_lock);
147 /* Ensure that the memory we're returning is cleared. */
148 ptr = ioremap_wc(obj->linear->start, size);
150 mutex_lock(&priv->linear_lock);
151 drm_mm_remove_node(obj->linear);
152 mutex_unlock(&priv->linear_lock);
158 memset_io(ptr, 0, size);
161 obj->phys_addr = obj->linear->start;
162 obj->dev_addr = obj->linear->start;
166 DRM_DEBUG_DRIVER("obj %p phys %#llx dev %#llx\n", obj,
167 (unsigned long long)obj->phys_addr,
168 (unsigned long long)obj->dev_addr);
174 armada_gem_map_object(struct drm_device *dev, struct armada_gem_object *dobj)
176 /* only linear objects need to be ioremap'd */
177 if (!dobj->addr && dobj->linear)
178 dobj->addr = ioremap_wc(dobj->phys_addr, dobj->obj.size);
182 struct armada_gem_object *
183 armada_gem_alloc_private_object(struct drm_device *dev, size_t size)
185 struct armada_gem_object *obj;
187 size = roundup_gem_size(size);
189 obj = kzalloc(sizeof(*obj), GFP_KERNEL);
193 drm_gem_private_object_init(dev, &obj->obj, size);
195 DRM_DEBUG_DRIVER("alloc private obj %p size %zu\n", obj, size);
200 static struct armada_gem_object *armada_gem_alloc_object(struct drm_device *dev,
203 struct armada_gem_object *obj;
204 struct address_space *mapping;
206 size = roundup_gem_size(size);
208 obj = kzalloc(sizeof(*obj), GFP_KERNEL);
212 if (drm_gem_object_init(dev, &obj->obj, size)) {
217 mapping = obj->obj.filp->f_mapping;
218 mapping_set_gfp_mask(mapping, GFP_HIGHUSER | __GFP_RECLAIMABLE);
220 DRM_DEBUG_DRIVER("alloc obj %p size %zu\n", obj, size);
225 /* Dumb alloc support */
226 int armada_gem_dumb_create(struct drm_file *file, struct drm_device *dev,
227 struct drm_mode_create_dumb *args)
229 struct armada_gem_object *dobj;
234 args->pitch = armada_pitch(args->width, args->bpp);
235 args->size = size = args->pitch * args->height;
237 dobj = armada_gem_alloc_private_object(dev, size);
241 ret = armada_gem_linear_back(dev, dobj);
245 ret = drm_gem_handle_create(file, &dobj->obj, &handle);
249 args->handle = handle;
251 /* drop reference from allocate - handle holds it now */
252 DRM_DEBUG_DRIVER("obj %p size %zu handle %#x\n", dobj, size, handle);
254 drm_gem_object_put_unlocked(&dobj->obj);
258 /* Private driver gem ioctls */
259 int armada_gem_create_ioctl(struct drm_device *dev, void *data,
260 struct drm_file *file)
262 struct drm_armada_gem_create *args = data;
263 struct armada_gem_object *dobj;
273 dobj = armada_gem_alloc_object(dev, size);
277 ret = drm_gem_handle_create(file, &dobj->obj, &handle);
281 args->handle = handle;
283 /* drop reference from allocate - handle holds it now */
284 DRM_DEBUG_DRIVER("obj %p size %zu handle %#x\n", dobj, size, handle);
286 drm_gem_object_put_unlocked(&dobj->obj);
290 /* Map a shmem-backed object into process memory space */
291 int armada_gem_mmap_ioctl(struct drm_device *dev, void *data,
292 struct drm_file *file)
294 struct drm_armada_gem_mmap *args = data;
295 struct armada_gem_object *dobj;
298 dobj = armada_gem_object_lookup(file, args->handle);
302 if (!dobj->obj.filp) {
303 drm_gem_object_put_unlocked(&dobj->obj);
307 addr = vm_mmap(dobj->obj.filp, 0, args->size, PROT_READ | PROT_WRITE,
308 MAP_SHARED, args->offset);
309 drm_gem_object_put_unlocked(&dobj->obj);
310 if (IS_ERR_VALUE(addr))
318 int armada_gem_pwrite_ioctl(struct drm_device *dev, void *data,
319 struct drm_file *file)
321 struct drm_armada_gem_pwrite *args = data;
322 struct armada_gem_object *dobj;
326 DRM_DEBUG_DRIVER("handle %u off %u size %u ptr 0x%llx\n",
327 args->handle, args->offset, args->size, args->ptr);
332 ptr = (char __user *)(uintptr_t)args->ptr;
334 if (!access_ok(ptr, args->size))
337 ret = fault_in_pages_readable(ptr, args->size);
341 dobj = armada_gem_object_lookup(file, args->handle);
345 /* Must be a kernel-mapped object */
349 if (args->offset > dobj->obj.size ||
350 args->size > dobj->obj.size - args->offset) {
351 DRM_ERROR("invalid size: object size %u\n", dobj->obj.size);
356 if (copy_from_user(dobj->addr + args->offset, ptr, args->size)) {
358 } else if (dobj->update) {
359 dobj->update(dobj->update_data);
364 drm_gem_object_put_unlocked(&dobj->obj);
369 static struct sg_table *
370 armada_gem_prime_map_dma_buf(struct dma_buf_attachment *attach,
371 enum dma_data_direction dir)
373 struct drm_gem_object *obj = attach->dmabuf->priv;
374 struct armada_gem_object *dobj = drm_to_armada_gem(obj);
375 struct scatterlist *sg;
376 struct sg_table *sgt;
379 sgt = kmalloc(sizeof(*sgt), GFP_KERNEL);
383 if (dobj->obj.filp) {
384 struct address_space *mapping;
387 count = dobj->obj.size / PAGE_SIZE;
388 if (sg_alloc_table(sgt, count, GFP_KERNEL))
391 mapping = dobj->obj.filp->f_mapping;
393 for_each_sg(sgt->sgl, sg, count, i) {
396 page = shmem_read_mapping_page(mapping, i);
402 sg_set_page(sg, page, PAGE_SIZE, 0);
405 if (dma_map_sg(attach->dev, sgt->sgl, sgt->nents, dir) == 0) {
409 } else if (dobj->page) {
410 /* Single contiguous page */
411 if (sg_alloc_table(sgt, 1, GFP_KERNEL))
414 sg_set_page(sgt->sgl, dobj->page, dobj->obj.size, 0);
416 if (dma_map_sg(attach->dev, sgt->sgl, sgt->nents, dir) == 0)
418 } else if (dobj->linear) {
419 /* Single contiguous physical region - no struct page */
420 if (sg_alloc_table(sgt, 1, GFP_KERNEL))
422 sg_dma_address(sgt->sgl) = dobj->dev_addr;
423 sg_dma_len(sgt->sgl) = dobj->obj.size;
430 for_each_sg(sgt->sgl, sg, num, i)
431 put_page(sg_page(sg));
439 static void armada_gem_prime_unmap_dma_buf(struct dma_buf_attachment *attach,
440 struct sg_table *sgt, enum dma_data_direction dir)
442 struct drm_gem_object *obj = attach->dmabuf->priv;
443 struct armada_gem_object *dobj = drm_to_armada_gem(obj);
447 dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents, dir);
449 if (dobj->obj.filp) {
450 struct scatterlist *sg;
451 for_each_sg(sgt->sgl, sg, sgt->nents, i)
452 put_page(sg_page(sg));
459 static void *armada_gem_dmabuf_no_kmap(struct dma_buf *buf, unsigned long n)
465 armada_gem_dmabuf_no_kunmap(struct dma_buf *buf, unsigned long n, void *addr)
470 armada_gem_dmabuf_mmap(struct dma_buf *buf, struct vm_area_struct *vma)
475 static const struct dma_buf_ops armada_gem_prime_dmabuf_ops = {
476 .map_dma_buf = armada_gem_prime_map_dma_buf,
477 .unmap_dma_buf = armada_gem_prime_unmap_dma_buf,
478 .release = drm_gem_dmabuf_release,
479 .map = armada_gem_dmabuf_no_kmap,
480 .unmap = armada_gem_dmabuf_no_kunmap,
481 .mmap = armada_gem_dmabuf_mmap,
485 armada_gem_prime_export(struct drm_device *dev, struct drm_gem_object *obj,
488 DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
490 exp_info.ops = &armada_gem_prime_dmabuf_ops;
491 exp_info.size = obj->size;
492 exp_info.flags = O_RDWR;
495 return drm_gem_dmabuf_export(dev, &exp_info);
498 struct drm_gem_object *
499 armada_gem_prime_import(struct drm_device *dev, struct dma_buf *buf)
501 struct dma_buf_attachment *attach;
502 struct armada_gem_object *dobj;
504 if (buf->ops == &armada_gem_prime_dmabuf_ops) {
505 struct drm_gem_object *obj = buf->priv;
506 if (obj->dev == dev) {
508 * Importing our own dmabuf(s) increases the
509 * refcount on the gem object itself.
511 drm_gem_object_get(obj);
516 attach = dma_buf_attach(buf, dev->dev);
518 return ERR_CAST(attach);
520 dobj = armada_gem_alloc_private_object(dev, buf->size);
522 dma_buf_detach(buf, attach);
523 return ERR_PTR(-ENOMEM);
526 dobj->obj.import_attach = attach;
530 * Don't call dma_buf_map_attachment() here - it maps the
531 * scatterlist immediately for DMA, and this is not always
532 * an appropriate thing to do.
537 int armada_gem_map_import(struct armada_gem_object *dobj)
541 dobj->sgt = dma_buf_map_attachment(dobj->obj.import_attach,
543 if (IS_ERR(dobj->sgt)) {
544 ret = PTR_ERR(dobj->sgt);
546 DRM_ERROR("dma_buf_map_attachment() error: %d\n", ret);
549 if (dobj->sgt->nents > 1) {
550 DRM_ERROR("dma_buf_map_attachment() returned an (unsupported) scattered list\n");
553 if (sg_dma_len(dobj->sgt->sgl) < dobj->obj.size) {
554 DRM_ERROR("dma_buf_map_attachment() returned a small buffer\n");
557 dobj->dev_addr = sg_dma_address(dobj->sgt->sgl);