linux/drivers/gpu/drm/drm_gem_cma_helper.c
YoungJun Cho 4368dd846d drm/gem: add mutex lock when using drm_gem_mmap_obj
The drm_gem_mmap_obj() has to be protected with dev->struct_mutex,
but some caller functions do not. So it adds mutex lock to missing
callers and adds assertion to check whether drm_gem_mmap_obj() is
called with mutex lock or not.

Signed-off-by: YoungJun Cho <yj44.cho@samsung.com>
Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@canonical.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
2013-06-28 12:30:15 +10:00

605 lines
14 KiB
C

/*
* drm gem CMA (contiguous memory allocator) helper functions
*
* Copyright (C) 2012 Sascha Hauer, Pengutronix
*
* Based on Samsung Exynos code
*
* Copyright (c) 2011 Samsung Electronics Co., Ltd.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/export.h>
#include <linux/dma-buf.h>
#include <linux/dma-mapping.h>
#include <drm/drmP.h>
#include <drm/drm.h>
#include <drm/drm_gem_cma_helper.h>
static unsigned int get_gem_mmap_offset(struct drm_gem_object *obj)
{
return (unsigned int)obj->map_list.hash.key << PAGE_SHIFT;
}
/*
* __drm_gem_cma_create - Create a GEM CMA object without allocating memory
* @drm: The drm device
* @size: The GEM object size
*
* This function creates and initializes a GEM CMA object of the given size, but
* doesn't allocate any memory to back the object.
*
* Return a struct drm_gem_cma_object* on success or ERR_PTR values on failure.
*/
static struct drm_gem_cma_object *
__drm_gem_cma_create(struct drm_device *drm, unsigned int size)
{
struct drm_gem_cma_object *cma_obj;
struct drm_gem_object *gem_obj;
int ret;
cma_obj = kzalloc(sizeof(*cma_obj), GFP_KERNEL);
if (!cma_obj)
return ERR_PTR(-ENOMEM);
gem_obj = &cma_obj->base;
ret = drm_gem_object_init(drm, gem_obj, size);
if (ret)
goto error;
ret = drm_gem_create_mmap_offset(gem_obj);
if (ret) {
drm_gem_object_release(gem_obj);
goto error;
}
return cma_obj;
error:
kfree(cma_obj);
return ERR_PTR(ret);
}
/*
* drm_gem_cma_create - allocate an object with the given size
*
* returns a struct drm_gem_cma_object* on success or ERR_PTR values
* on failure.
*/
struct drm_gem_cma_object *drm_gem_cma_create(struct drm_device *drm,
unsigned int size)
{
struct drm_gem_cma_object *cma_obj;
struct sg_table *sgt = NULL;
int ret;
size = round_up(size, PAGE_SIZE);
cma_obj = __drm_gem_cma_create(drm, size);
if (IS_ERR(cma_obj))
return cma_obj;
cma_obj->vaddr = dma_alloc_writecombine(drm->dev, size,
&cma_obj->paddr, GFP_KERNEL | __GFP_NOWARN);
if (!cma_obj->vaddr) {
dev_err(drm->dev, "failed to allocate buffer with size %d\n",
size);
ret = -ENOMEM;
goto error;
}
sgt = kzalloc(sizeof(*cma_obj->sgt), GFP_KERNEL);
if (sgt == NULL) {
ret = -ENOMEM;
goto error;
}
ret = dma_get_sgtable(drm->dev, sgt, cma_obj->vaddr,
cma_obj->paddr, size);
if (ret < 0)
goto error;
cma_obj->sgt = sgt;
return cma_obj;
error:
kfree(sgt);
drm_gem_cma_free_object(&cma_obj->base);
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(drm_gem_cma_create);
/*
* drm_gem_cma_create_with_handle - allocate an object with the given
* size and create a gem handle on it
*
* returns a struct drm_gem_cma_object* on success or ERR_PTR values
* on failure.
*/
static struct drm_gem_cma_object *drm_gem_cma_create_with_handle(
struct drm_file *file_priv,
struct drm_device *drm, unsigned int size,
unsigned int *handle)
{
struct drm_gem_cma_object *cma_obj;
struct drm_gem_object *gem_obj;
int ret;
cma_obj = drm_gem_cma_create(drm, size);
if (IS_ERR(cma_obj))
return cma_obj;
gem_obj = &cma_obj->base;
/*
* allocate a id of idr table where the obj is registered
* and handle has the id what user can see.
*/
ret = drm_gem_handle_create(file_priv, gem_obj, handle);
if (ret)
goto err_handle_create;
/* drop reference from allocate - handle holds it now. */
drm_gem_object_unreference_unlocked(gem_obj);
return cma_obj;
err_handle_create:
drm_gem_cma_free_object(gem_obj);
return ERR_PTR(ret);
}
/*
* drm_gem_cma_free_object - (struct drm_driver)->gem_free_object callback
* function
*/
void drm_gem_cma_free_object(struct drm_gem_object *gem_obj)
{
struct drm_gem_cma_object *cma_obj;
if (gem_obj->map_list.map)
drm_gem_free_mmap_offset(gem_obj);
cma_obj = to_drm_gem_cma_obj(gem_obj);
if (cma_obj->vaddr) {
dma_free_writecombine(gem_obj->dev->dev, cma_obj->base.size,
cma_obj->vaddr, cma_obj->paddr);
if (cma_obj->sgt) {
sg_free_table(cma_obj->sgt);
kfree(cma_obj->sgt);
}
} else if (gem_obj->import_attach) {
drm_prime_gem_destroy(gem_obj, cma_obj->sgt);
}
drm_gem_object_release(gem_obj);
kfree(cma_obj);
}
EXPORT_SYMBOL_GPL(drm_gem_cma_free_object);
/*
* drm_gem_cma_dumb_create - (struct drm_driver)->dumb_create callback
* function
*
* This aligns the pitch and size arguments to the minimum required. wrap
* this into your own function if you need bigger alignment.
*/
int drm_gem_cma_dumb_create(struct drm_file *file_priv,
struct drm_device *dev, struct drm_mode_create_dumb *args)
{
struct drm_gem_cma_object *cma_obj;
int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
if (args->pitch < min_pitch)
args->pitch = min_pitch;
if (args->size < args->pitch * args->height)
args->size = args->pitch * args->height;
cma_obj = drm_gem_cma_create_with_handle(file_priv, dev,
args->size, &args->handle);
return PTR_RET(cma_obj);
}
EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_create);
/*
* drm_gem_cma_dumb_map_offset - (struct drm_driver)->dumb_map_offset callback
* function
*/
int drm_gem_cma_dumb_map_offset(struct drm_file *file_priv,
struct drm_device *drm, uint32_t handle, uint64_t *offset)
{
struct drm_gem_object *gem_obj;
mutex_lock(&drm->struct_mutex);
gem_obj = drm_gem_object_lookup(drm, file_priv, handle);
if (!gem_obj) {
dev_err(drm->dev, "failed to lookup gem object\n");
mutex_unlock(&drm->struct_mutex);
return -EINVAL;
}
*offset = get_gem_mmap_offset(gem_obj);
drm_gem_object_unreference(gem_obj);
mutex_unlock(&drm->struct_mutex);
return 0;
}
EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_map_offset);
const struct vm_operations_struct drm_gem_cma_vm_ops = {
.open = drm_gem_vm_open,
.close = drm_gem_vm_close,
};
EXPORT_SYMBOL_GPL(drm_gem_cma_vm_ops);
static int drm_gem_cma_mmap_obj(struct drm_gem_cma_object *cma_obj,
struct vm_area_struct *vma)
{
int ret;
ret = remap_pfn_range(vma, vma->vm_start, cma_obj->paddr >> PAGE_SHIFT,
vma->vm_end - vma->vm_start, vma->vm_page_prot);
if (ret)
drm_gem_vm_close(vma);
return ret;
}
/*
* drm_gem_cma_mmap - (struct file_operation)->mmap callback function
*/
int drm_gem_cma_mmap(struct file *filp, struct vm_area_struct *vma)
{
struct drm_gem_cma_object *cma_obj;
struct drm_gem_object *gem_obj;
int ret;
ret = drm_gem_mmap(filp, vma);
if (ret)
return ret;
gem_obj = vma->vm_private_data;
cma_obj = to_drm_gem_cma_obj(gem_obj);
return drm_gem_cma_mmap_obj(cma_obj, vma);
}
EXPORT_SYMBOL_GPL(drm_gem_cma_mmap);
/*
* drm_gem_cma_dumb_destroy - (struct drm_driver)->dumb_destroy callback function
*/
int drm_gem_cma_dumb_destroy(struct drm_file *file_priv,
struct drm_device *drm, unsigned int handle)
{
return drm_gem_handle_delete(file_priv, handle);
}
EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_destroy);
#ifdef CONFIG_DEBUG_FS
void drm_gem_cma_describe(struct drm_gem_cma_object *cma_obj, struct seq_file *m)
{
struct drm_gem_object *obj = &cma_obj->base;
struct drm_device *dev = obj->dev;
uint64_t off = 0;
WARN_ON(!mutex_is_locked(&dev->struct_mutex));
if (obj->map_list.map)
off = (uint64_t)obj->map_list.hash.key;
seq_printf(m, "%2d (%2d) %08llx %08Zx %p %d",
obj->name, obj->refcount.refcount.counter,
off, cma_obj->paddr, cma_obj->vaddr, obj->size);
seq_printf(m, "\n");
}
EXPORT_SYMBOL_GPL(drm_gem_cma_describe);
#endif
/* -----------------------------------------------------------------------------
* DMA-BUF
*/
struct drm_gem_cma_dmabuf_attachment {
struct sg_table sgt;
enum dma_data_direction dir;
};
static int drm_gem_cma_dmabuf_attach(struct dma_buf *dmabuf, struct device *dev,
struct dma_buf_attachment *attach)
{
struct drm_gem_cma_dmabuf_attachment *cma_attach;
cma_attach = kzalloc(sizeof(*cma_attach), GFP_KERNEL);
if (!cma_attach)
return -ENOMEM;
cma_attach->dir = DMA_NONE;
attach->priv = cma_attach;
return 0;
}
static void drm_gem_cma_dmabuf_detach(struct dma_buf *dmabuf,
struct dma_buf_attachment *attach)
{
struct drm_gem_cma_dmabuf_attachment *cma_attach = attach->priv;
struct sg_table *sgt;
if (cma_attach == NULL)
return;
sgt = &cma_attach->sgt;
if (cma_attach->dir != DMA_NONE)
dma_unmap_sg(attach->dev, sgt->sgl, sgt->nents,
cma_attach->dir);
sg_free_table(sgt);
kfree(cma_attach);
attach->priv = NULL;
}
static struct sg_table *
drm_gem_cma_dmabuf_map(struct dma_buf_attachment *attach,
enum dma_data_direction dir)
{
struct drm_gem_cma_dmabuf_attachment *cma_attach = attach->priv;
struct drm_gem_cma_object *cma_obj = attach->dmabuf->priv;
struct drm_device *drm = cma_obj->base.dev;
struct scatterlist *rd, *wr;
struct sg_table *sgt;
unsigned int i;
int nents, ret;
DRM_DEBUG_PRIME("\n");
if (WARN_ON(dir == DMA_NONE))
return ERR_PTR(-EINVAL);
/* Return the cached mapping when possible. */
if (cma_attach->dir == dir)
return &cma_attach->sgt;
/* Two mappings with different directions for the same attachment are
* not allowed.
*/
if (WARN_ON(cma_attach->dir != DMA_NONE))
return ERR_PTR(-EBUSY);
sgt = &cma_attach->sgt;
ret = sg_alloc_table(sgt, cma_obj->sgt->orig_nents, GFP_KERNEL);
if (ret) {
DRM_ERROR("failed to alloc sgt.\n");
return ERR_PTR(-ENOMEM);
}
mutex_lock(&drm->struct_mutex);
rd = cma_obj->sgt->sgl;
wr = sgt->sgl;
for (i = 0; i < sgt->orig_nents; ++i) {
sg_set_page(wr, sg_page(rd), rd->length, rd->offset);
rd = sg_next(rd);
wr = sg_next(wr);
}
nents = dma_map_sg(attach->dev, sgt->sgl, sgt->orig_nents, dir);
if (!nents) {
DRM_ERROR("failed to map sgl with iommu.\n");
sg_free_table(sgt);
sgt = ERR_PTR(-EIO);
goto done;
}
cma_attach->dir = dir;
attach->priv = cma_attach;
DRM_DEBUG_PRIME("buffer size = %zu\n", cma_obj->base.size);
done:
mutex_unlock(&drm->struct_mutex);
return sgt;
}
static void drm_gem_cma_dmabuf_unmap(struct dma_buf_attachment *attach,
struct sg_table *sgt,
enum dma_data_direction dir)
{
/* Nothing to do. */
}
static void drm_gem_cma_dmabuf_release(struct dma_buf *dmabuf)
{
struct drm_gem_cma_object *cma_obj = dmabuf->priv;
DRM_DEBUG_PRIME("%s\n", __FILE__);
/*
* drm_gem_cma_dmabuf_release() call means that file object's
* f_count is 0 and it calls drm_gem_object_handle_unreference()
* to drop the references that these values had been increased
* at drm_prime_handle_to_fd()
*/
if (cma_obj->base.export_dma_buf == dmabuf) {
cma_obj->base.export_dma_buf = NULL;
/*
* drop this gem object refcount to release allocated buffer
* and resources.
*/
drm_gem_object_unreference_unlocked(&cma_obj->base);
}
}
static void *drm_gem_cma_dmabuf_kmap_atomic(struct dma_buf *dmabuf,
unsigned long page_num)
{
/* TODO */
return NULL;
}
static void drm_gem_cma_dmabuf_kunmap_atomic(struct dma_buf *dmabuf,
unsigned long page_num, void *addr)
{
/* TODO */
}
static void *drm_gem_cma_dmabuf_kmap(struct dma_buf *dmabuf,
unsigned long page_num)
{
/* TODO */
return NULL;
}
static void drm_gem_cma_dmabuf_kunmap(struct dma_buf *dmabuf,
unsigned long page_num, void *addr)
{
/* TODO */
}
static int drm_gem_cma_dmabuf_mmap(struct dma_buf *dmabuf,
struct vm_area_struct *vma)
{
struct drm_gem_cma_object *cma_obj = dmabuf->priv;
struct drm_gem_object *gem_obj = &cma_obj->base;
struct drm_device *dev = gem_obj->dev;
int ret;
mutex_lock(&dev->struct_mutex);
ret = drm_gem_mmap_obj(gem_obj, gem_obj->size, vma);
mutex_unlock(&dev->struct_mutex);
if (ret < 0)
return ret;
return drm_gem_cma_mmap_obj(cma_obj, vma);
}
static void *drm_gem_cma_dmabuf_vmap(struct dma_buf *dmabuf)
{
struct drm_gem_cma_object *cma_obj = dmabuf->priv;
return cma_obj->vaddr;
}
static struct dma_buf_ops drm_gem_cma_dmabuf_ops = {
.attach = drm_gem_cma_dmabuf_attach,
.detach = drm_gem_cma_dmabuf_detach,
.map_dma_buf = drm_gem_cma_dmabuf_map,
.unmap_dma_buf = drm_gem_cma_dmabuf_unmap,
.kmap = drm_gem_cma_dmabuf_kmap,
.kmap_atomic = drm_gem_cma_dmabuf_kmap_atomic,
.kunmap = drm_gem_cma_dmabuf_kunmap,
.kunmap_atomic = drm_gem_cma_dmabuf_kunmap_atomic,
.mmap = drm_gem_cma_dmabuf_mmap,
.vmap = drm_gem_cma_dmabuf_vmap,
.release = drm_gem_cma_dmabuf_release,
};
struct dma_buf *drm_gem_cma_dmabuf_export(struct drm_device *drm,
struct drm_gem_object *obj, int flags)
{
struct drm_gem_cma_object *cma_obj = to_drm_gem_cma_obj(obj);
return dma_buf_export(cma_obj, &drm_gem_cma_dmabuf_ops,
cma_obj->base.size, flags);
}
EXPORT_SYMBOL_GPL(drm_gem_cma_dmabuf_export);
struct drm_gem_object *drm_gem_cma_dmabuf_import(struct drm_device *drm,
struct dma_buf *dma_buf)
{
struct drm_gem_cma_object *cma_obj;
struct dma_buf_attachment *attach;
struct sg_table *sgt;
int ret;
DRM_DEBUG_PRIME("%s\n", __FILE__);
/* is this one of own objects? */
if (dma_buf->ops == &drm_gem_cma_dmabuf_ops) {
struct drm_gem_object *obj;
cma_obj = dma_buf->priv;
obj = &cma_obj->base;
/* is it from our device? */
if (obj->dev == drm) {
/*
* Importing dmabuf exported from out own gem increases
* refcount on gem itself instead of f_count of dmabuf.
*/
drm_gem_object_reference(obj);
dma_buf_put(dma_buf);
return obj;
}
}
/* Create a CMA GEM buffer. */
cma_obj = __drm_gem_cma_create(drm, dma_buf->size);
if (IS_ERR(cma_obj))
return ERR_PTR(PTR_ERR(cma_obj));
/* Attach to the buffer and map it. Make sure the mapping is contiguous
* on the device memory bus, as that's all we support.
*/
attach = dma_buf_attach(dma_buf, drm->dev);
if (IS_ERR(attach)) {
ret = -EINVAL;
goto error_gem_free;
}
sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
if (IS_ERR_OR_NULL(sgt)) {
ret = sgt ? PTR_ERR(sgt) : -ENOMEM;
goto error_buf_detach;
}
if (sgt->nents != 1) {
ret = -EINVAL;
goto error_buf_unmap;
}
cma_obj->base.import_attach = attach;
cma_obj->paddr = sg_dma_address(sgt->sgl);
cma_obj->sgt = sgt;
DRM_DEBUG_PRIME("dma_addr = 0x%x, size = %zu\n", cma_obj->paddr,
dma_buf->size);
return &cma_obj->base;
error_buf_unmap:
dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL);
error_buf_detach:
dma_buf_detach(dma_buf, attach);
error_gem_free:
drm_gem_cma_free_object(&cma_obj->base);
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(drm_gem_cma_dmabuf_import);