/*
* Copyright © 2012 Red Hat
*
* 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:
* Dave Airlie <airlied@redhat.com>
* Rob Clark <rob.clark@linaro.org>
*
*/
#include <linux/export.h>
#include <linux/dma-buf.h>
#include <linux/rbtree.h>
#include <drm/drm_drv.h>
#include <drm/drm_file.h>
#include <drm/drm_framebuffer.h>
#include <drm/drm_gem.h>
#include <drm/drm_prime.h>
#include "drm_internal.h"
/*
* DMA-BUF/GEM Object references and lifetime overview:
*
* On the export the dma_buf holds a reference to the exporting GEM
* object. It takes this reference in handle_to_fd_ioctl, when it
* first calls .prime_export and stores the exporting GEM object in
* the dma_buf priv. This reference needs to be released when the
* final reference to the &dma_buf itself is dropped and its
* &dma_buf_ops.release function is called. For GEM-based drivers,
* the dma_buf should be exported using drm_gem_dmabuf_export() and
* then released by drm_gem_dmabuf_release().
*
* On the import the importing GEM object holds a reference to the
* dma_buf (which in turn holds a ref to the exporting GEM object).
* It takes that reference in the fd_to_handle ioctl.
* It calls dma_buf_get, creates an attachment to it and stores the
* attachment in the GEM object. When this attachment is destroyed
* when the imported object is destroyed, we remove the attachment
* and drop the reference to the dma_buf.
*
* When all the references to the &dma_buf are dropped, i.e. when
* userspace has closed both handles to the imported GEM object (through the
* FD_TO_HANDLE IOCTL) and closed the file descriptor of the exported
* (through the HANDLE_TO_FD IOCTL) dma_buf, and all kernel-internal references
* are also gone, then the dma_buf gets destroyed. This can also happen as a
* part of the clean up procedure in the drm_release() function if userspace
* fails to properly clean up. Note that both the kernel and userspace (by
* keeeping the PRIME file descriptors open) can hold references onto a
* &dma_buf.
*
* Thus the chain of references always flows in one direction
* (avoiding loops): importing_gem -> dmabuf -> exporting_gem
*
* Self-importing: if userspace is using PRIME as a replacement for flink
* then it will get a fd->handle request for a GEM object that it created.
* Drivers should detect this situation and return back the gem object
* from the dma-buf private. Prime will do this automatically for drivers that
* use the drm_gem_prime_{import,export} helpers.
*
* GEM struct &dma_buf_ops symbols are now exported. They can be resued by
* drivers which implement GEM interface.
*/
struct drm_prime_member {
struct dma_buf *dma_buf;
uint32_t handle;
struct rb_node dmabuf_rb;
struct rb_node handle_rb;
};
static int drm_prime_add_buf_handle(struct drm_prime_file_private *prime_fpriv,
struct dma_buf *dma_buf, uint32_t handle)
{
struct drm_prime_member *member;
struct rb_node **p, *rb;
member = kmalloc(sizeof(*member), GFP_KERNEL);
if (!member)
return -ENOMEM;
get_dma_buf(dma_buf);
member->dma_buf = dma_buf;
member->handle = handle;
rb = NULL;
p = &prime_fpriv->dmabufs.rb_node;
while (*p) {
struct drm_prime_member *pos;
rb = *p;
pos = rb_entry(rb, struct drm_prime_member, dmabuf_rb);
if (dma_buf > pos->dma_buf)
p = &rb->rb_right;
else
p = &rb->rb_left;
}
rb_link_node(&member->dmabuf_rb, rb, p);
rb_insert_color(&member->dmabuf_rb, &prime_fpriv->dmabufs);
rb = NULL;
p = &prime_fpriv->handles.rb_node;
while (*p) {
struct drm_prime_member *pos;
rb = *p;
pos = rb_entry(rb, struct drm_prime_member, handle_rb);
if (handle > pos->handle)
p = &rb->rb_right;
else
p = &rb->rb_left;
}
rb_link_node(&member->handle_rb, rb, p);
rb_insert_color(&member->handle_rb, &prime_fpriv->handles);
return 0;
}
static struct dma_buf *drm_prime_lookup_buf_by_handle(struct drm_prime_file_private *prime_fpriv,
uint32_t handle)
{
struct rb_node *rb;
rb = prime_fpriv->handles.rb_node;
while (rb) {
struct drm_prime_member *member;
member = rb_entry(rb, struct drm_prime_member, handle_rb);
if (member->handle == handle)
return member->dma_buf;
else if (member->handle < handle)
rb = rb->rb_right;
else
rb = rb->rb_left;
}
return NULL;
}
static int drm_prime_lookup_buf_handle(struct drm_prime_file_private *prime_fpriv,
struct dma_buf *dma_buf,
uint32_t *handle)
{
struct rb_node *rb;
rb = prime_fpriv->dmabufs.rb_node;
while (rb) {
struct drm_prime_member *member;
member = rb_entry(rb, struct drm_prime_member, dmabuf_rb);
if (member->dma_buf == dma_buf) {
*handle = member->handle;
return 0;
} else if (member->dma_buf < dma_buf) {
rb = rb->rb_right;
} else {
rb = rb->rb_left;
}
}
return -ENOENT;
}
/**
* drm_gem_map_attach - dma_buf attach implementation for GEM
* @dma_buf: buffer to attach device to
* @attach: buffer attachment data
*
* Calls &drm_driver.gem_prime_pin for device specific handling. This can be
* used as the &dma_buf_ops.attach callback.
*
* Returns 0 on success, negative error code on failure.
*/
int drm_gem_map_attach(struct dma_buf *dma_buf,
struct dma_buf_attachment *attach)
{
struct drm_gem_object *obj = dma_buf->priv;
return drm_gem_pin(obj);
}
EXPORT_SYMBOL(drm_gem_map_attach);
/**
* drm_gem_map_detach - dma_buf detach implementation for GEM
* @dma_buf: buffer to detach from
* @attach: attachment to be detached
*
* Cleans up &dma_buf_attachment. This can be used as the &dma_buf_ops.detach
* callback.
*/
void drm_gem_map_detach(struct dma_buf *dma_buf,
struct dma_buf_attachment *attach)
{
struct drm_gem_object *obj = dma_buf->priv;
drm_gem_unpin(obj);
}
EXPORT_SYMBOL(drm_gem_map_detach);
void drm_prime_remove_buf_handle_locked(struct drm_prime_file_private *prime_fpriv,
struct dma_buf *dma_buf)
{
struct rb_node *rb;
rb = prime_fpriv->dmabufs.rb_node;
while (rb) {
struct drm_prime_member *member;
member = rb_entry(rb, struct drm_prime_member, dmabuf_rb);
if (member->dma_buf == dma_buf) {
rb_erase(&member->handle_rb, &prime_fpriv->handles);
rb_erase(&member->dmabuf_rb, &prime_fpriv->dmabufs);
dma_buf_put(dma_buf);
kfree(member);
return;
} else if (member->dma_buf < dma_buf) {
rb = rb->rb_right;
} else {
rb = rb->rb_left;
}
}
}
/**
* drm_gem_map_dma_buf - map_dma_buf implementation for GEM
* @attach: attachment whose scatterlist is to be returned
* @dir: direction of DMA transfer
*
* Calls &drm_driver.gem_prime_get_sg_table and then maps the scatterlist. This
* can be used as the &dma_buf_ops.map_dma_buf callback.
*
* Returns sg_table containing the scatterlist to be returned; returns ERR_PTR
* on error. May return -EINTR if it is interrupted by a signal.
*/
struct sg_table *drm_gem_map_dma_buf(struct dma_buf_attachment *attach,
enum dma_data_direction dir)
{
struct drm_gem_object *obj = attach->dmabuf->priv;
struct sg_table *sgt;
if (WARN_ON(dir == DMA_NONE))
return ERR_PTR(-EINVAL);
if (obj->funcs)
sgt = obj->funcs->get_sg_table(obj);
else
sgt = obj->dev->driver->gem_prime_get_sg_table(obj);
if (!dma_map_sg_attrs(attach->dev, sgt->sgl, sgt->nents, dir,
DMA_ATTR_SKIP_CPU_SYNC)) {
sg_free_table(sgt);
kfree(sgt);
sgt = ERR_PTR(-ENOMEM);
}
return sgt;
}
EXPORT_SYMBOL(drm_gem_map_dma_buf);
/**
* drm_gem_unmap_dma_buf - unmap_dma_buf implementation for GEM
* @attach: attachment to unmap buffer from
* @sgt: scatterlist info of the buffer to unmap
* @dir: direction of DMA transfer
*
* This can be used as the &dma_buf_ops.unmap_dma_buf callback.
*/
void drm_gem_unmap_dma_buf(struct dma_buf_attachment *attach,
struct sg_table *sgt,
enum dma_data_direction dir)
{
if (!sgt)
return;
dma_unmap_sg_attrs(attach->dev, sgt->sgl, sgt->nents, dir,
DMA_ATTR_SKIP_CPU_SYNC);
sg_free_table(sgt);
kfree(sgt);
}
EXPORT_SYMBOL(drm_gem_unmap_dma_buf);
/**
* drm_gem_dmabuf_export - dma_buf export implementation for GEM
* @dev: parent device for the exported dmabuf
* @exp_info: the export information used by dma_buf_export()
*
* This wraps dma_buf_export() for use by generic GEM drivers that are using
* drm_gem_dmabuf_release(). In addition to calling dma_buf_export(), we take
* a reference to the &drm_device and the exported &drm_gem_object (stored in
* &dma_buf_export_info.priv) which is released by drm_gem_dmabuf_release().
*
* Returns the new dmabuf.
*/
struct dma_buf *drm_gem_dmabuf_export(struct drm_device *dev,
struct dma_buf_export_info *exp_info)
{
struct dma_buf *dma_buf;
dma_buf = dma_buf_export(exp_info);
if (IS_ERR(dma_buf))
return dma_buf;
drm_dev_get(dev);
drm_gem_object_get(exp_info->priv);
return dma_buf;
}
EXPORT_SYMBOL(drm_gem_dmabuf_export);
/**
* drm_gem_dmabuf_release - dma_buf release implementation for GEM
* @dma_buf: buffer to be released
*
* Generic release function for dma_bufs exported as PRIME buffers. GEM drivers
* must use this in their dma_buf ops structure as the release callback.
* drm_gem_dmabuf_release() should be used in conjunction with
* drm_gem_dmabuf_export().
*/
void drm_gem_dmabuf_release(struct dma_buf *dma_buf)
{
struct drm_gem_object *obj = dma_buf->priv;
struct drm_device *dev = obj->dev;
/* drop the reference on the export fd holds */
drm_gem_object_put_unlocked(obj);
drm_dev_put(dev);
}
EXPORT_SYMBOL(drm_gem_dmabuf_release);
/**
* drm_gem_dmabuf_vmap - dma_buf vmap implementation for GEM
* @dma_buf: buffer to be mapped
*
* Sets up a kernel virtual mapping. This can be used as the &dma_buf_ops.vmap
* callback.
*
* Returns the kernel virtual address.
*/
void *drm_gem_dmabuf_vmap(struct dma_buf *dma_buf)
{
struct drm_gem_object *obj = dma_buf->priv;
void *vaddr;
vaddr = drm_gem_vmap(obj);
if (IS_ERR(vaddr))
vaddr = NULL;
return vaddr;
}
EXPORT_SYMBOL(drm_gem_dmabuf_vmap);
/**
* drm_gem_dmabuf_vunmap - dma_buf vunmap implementation for GEM
* @dma_buf: buffer to be unmapped
* @vaddr: the virtual address of the buffer
*
* Releases a kernel virtual mapping. This can be used as the
* &dma_buf_ops.vunmap callback.
*/
void drm_gem_dmabuf_vunmap(struct dma_buf *dma_buf, void *vaddr)
{
struct drm_gem_object *obj = dma_buf->priv;
drm_gem_vunmap(obj, vaddr);
}
EXPORT_SYMBOL(drm_gem_dmabuf_vunmap);
/**
* drm_gem_dmabuf_mmap - dma_buf mmap implementation for GEM
* @dma_buf: buffer to be mapped
* @vma: virtual address range
*
* Provides memory mapping for the buffer. This can be used as the
* &dma_buf_ops.mmap callback.
*
* Returns 0 on success or a negative error code on failure.
*/
int drm_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma)
{
struct drm_gem_object *obj = dma_buf->priv;
struct drm_device *dev = obj->dev;
if (!dev->driver->gem_prime_mmap)
return -ENOSYS;
return dev->driver->gem_prime_mmap(obj, vma);
}
EXPORT_SYMBOL(drm_gem_dmabuf_mmap);
static const struct dma_buf_ops drm_gem_prime_dmabuf_ops = {
.cache_sgt_mapping = true,
.attach = drm_gem_map_attach,
.detach = drm_gem_map_detach,
.map_dma_buf = drm_gem_map_dma_buf,
.unmap_dma_buf = drm_gem_unmap_dma_buf,
.release = drm_gem_dmabuf_release,
.mmap = drm_gem_dmabuf_mmap,
.vmap = drm_gem_dmabuf_vmap,
.vunmap = drm_gem_dmabuf_vunmap,
};
/**
* DOC: PRIME Helpers
*
* Drivers can implement @gem_prime_export and @gem_prime_import in terms of
* simpler APIs by using the helper functions @drm_gem_prime_export and
* @drm_gem_prime_import. These functions implement dma-buf support in terms of
* six lower-level driver callbacks:
*
* Export callbacks:
*
* * @gem_prime_pin (optional): prepare a GEM object for exporting
* * @gem_prime_get_sg_table: provide a scatter/gather table of pinned pages
* * @gem_prime_vmap: vmap a buffer exported by your driver
* * @gem_prime_vunmap: vunmap a buffer exported by your driver
* * @gem_prime_mmap (optional): mmap a buffer exported by your driver
*
* Import callback:
*
* * @gem_prime_import_sg_table (import): produce a GEM object from another
* driver's scatter/gather table
*/
/**
* drm_gem_prime_export - helper library implementation of the export callback
* @dev: drm_device to export from
* @obj: GEM object to export
* @flags: flags like DRM_CLOEXEC and DRM_RDWR
*
* This is the implementation of the gem_prime_export functions for GEM drivers
* using the PRIME helpers.
*/
struct dma_buf *drm_gem_prime_export(struct drm_device *dev,
struct drm_gem_object *obj,
int flags)
{
struct dma_buf_export_info exp_info = {
.exp_name = KBUILD_MODNAME, /* white lie for debug */
.owner = dev->driver->fops->owner,
.ops = &drm_gem_prime_dmabuf_ops,
.size = obj->size,
.flags = flags,
.priv = obj,
.resv = obj->resv,
};
if (dev->driver->gem_prime_res_obj)
exp_info.resv = dev->driver->gem_prime_res_obj(obj);
return drm_gem_dmabuf_export(dev, &exp_info);
}
EXPORT_SYMBOL(drm_gem_prime_export);
static struct dma_buf *export_and_register_object(struct drm_device *dev,
struct drm_gem_object *obj,
uint32_t flags)
{
struct dma_buf *dmabuf;
/* prevent races with concurrent gem_close. */
if (obj->handle_count == 0) {
dmabuf = ERR_PTR(-ENOENT);
return dmabuf;
}
if (obj->funcs && obj->funcs->export)
dmabuf = obj->funcs->export(obj, flags);
else if (dev->driver->gem_prime_export)
dmabuf = dev->driver->gem_prime_export(dev, obj, flags);
else
dmabuf = drm_gem_prime_export(dev, obj, flags);
if (IS_ERR(dmabuf)) {
/* normally the created dma-buf takes ownership of the ref,
* but if that fails then drop the ref
*/
return dmabuf;
}
/*
* Note that callers do not need to clean up the export cache
* since the check for obj->handle_count guarantees that someone
* will clean it up.
*/
obj->dma_buf = dmabuf;
get_dma_buf(obj->dma_buf);
return dmabuf;
}
/**
* drm_gem_prime_handle_to_fd - PRIME export function for GEM drivers
* @dev: dev to export the buffer from
* @file_priv: drm file-private structure
* @handle: buffer handle to export
* @flags: flags like DRM_CLOEXEC
* @prime_fd: pointer to storage for the fd id of the create dma-buf
*
* This is the PRIME export function which must be used mandatorily by GEM
* drivers to ensure correct lifetime management of the underlying GEM object.
* The actual exporting from GEM object to a dma-buf is done through the
* gem_prime_export driver callback.
*/
int drm_gem_prime_handle_to_fd(struct drm_device *dev,
struct drm_file *file_priv, uint32_t handle,
uint32_t flags,
int *prime_fd)
{
struct drm_gem_object *obj;
int ret = 0;
struct dma_buf *dmabuf;
mutex_lock(&file_priv->prime.lock);
obj = drm_gem_object_lookup(file_priv, handle);
if (!obj) {
ret = -ENOENT;
goto out_unlock;
}
dmabuf = drm_prime_lookup_buf_by_handle(&file_priv->prime, handle);
if (dmabuf) {
get_dma_buf(dmabuf);
goto out_have_handle;
}
mutex_lock(&dev->object_name_lock);
/* re-export the original imported object */
if (obj->import_attach) {
dmabuf = obj->import_attach->dmabuf;
get_dma_buf(dmabuf);
goto out_have_obj;
}
if (obj->dma_buf) {
get_dma_buf(obj->dma_buf);
dmabuf = obj->dma_buf;
goto out_have_obj;
}
dmabuf = export_and_register_object(dev, obj, flags);
if (IS_ERR(dmabuf)) {
/* normally the created dma-buf takes ownership of the ref,
* but if that fails then drop the ref
*/
ret = PTR_ERR(dmabuf);
mutex_unlock(&dev->object_name_lock);
goto out;
}
out_have_obj:
/*
* If we've exported this buffer then cheat and add it to the import list
* so we get the correct handle back. We must do this under the
* protection of dev->object_name_lock to ensure that a racing gem close
* ioctl doesn't miss to remove this buffer handle from the cache.
*/
ret = drm_prime_add_buf_handle(&file_priv->prime,
dmabuf, handle);
mutex_unlock(&dev->object_name_lock);
if (ret)
goto fail_put_dmabuf;
out_have_handle:
ret = dma_buf_fd(dmabuf, flags);
/*
* We must _not_ remove the buffer from the handle cache since the newly
* created dma buf is already linked in the global obj->dma_buf pointer,
* and that is invariant as long as a userspace gem handle exists.
* Closing the handle will clean out the cache anyway, so we don't leak.
*/
if (ret < 0) {
goto fail_put_dmabuf;
} else {
*prime_fd = ret;
ret = 0;
}
goto out;
fail_put_dmabuf:
dma_buf_put(dmabuf);
out:
drm_gem_object_put_unlocked(obj);
out_unlock:
mutex_unlock(&file_priv->prime.lock);
return ret;
}
EXPORT_SYMBOL(drm_gem_prime_handle_to_fd);
/**
* drm_gem_prime_mmap - PRIME mmap function for GEM drivers
* @obj: GEM object
* @vma: Virtual address range
*
* This function sets up a userspace mapping for PRIME exported buffers using
* the same codepath that is used for regular GEM buffer mapping on the DRM fd.
* The fake GEM offset is added to vma->vm_pgoff and &drm_driver->fops->mmap is
* called to set up the mapping.
*
* Drivers can use this as their &drm_driver.gem_prime_mmap callback.
*/
int drm_gem_prime_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
{
struct drm_file *priv;
struct file *fil;
int ret;
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
fil = kzalloc(sizeof(*fil), GFP_KERNEL);
if (!priv || !fil) {
ret = -ENOMEM;
goto out;
}
/* Used by drm_gem_mmap() to lookup the GEM object */
priv->minor = obj->dev->primary;
fil->private_data = priv;
ret = drm_vma_node_allow(&obj->vma_node, priv);
if (ret)
goto out;
vma->vm_pgoff += drm_vma_node_start(&obj->vma_node);
ret = obj->dev->driver->fops->mmap(fil, vma);
drm_vma_node_revoke(&obj->vma_node, priv);
out:
kfree(priv);
kfree(fil);
return ret;
}
EXPORT_SYMBOL(drm_gem_prime_mmap);
/**
* drm_gem_prime_import_dev - core implementation of the import callback
* @dev: drm_device to import into
* @dma_buf: dma-buf object to import
* @attach_dev: struct device to dma_buf attach
*
* This is the core of drm_gem_prime_import. It's designed to be called by
* drivers who want to use a different device structure than dev->dev for
* attaching via dma_buf.
*/
struct drm_gem_object *drm_gem_prime_import_dev(struct drm_device *dev,
struct dma_buf *dma_buf,
struct device *attach_dev)
{
struct dma_buf_attachment *attach;
struct sg_table *sgt;
struct drm_gem_object *obj;
int ret;
if (dma_buf->ops == &drm_gem_prime_dmabuf_ops) {
obj = dma_buf->priv;
if (obj->dev == dev) {
/*
* Importing dmabuf exported from out own gem increases
* refcount on gem itself instead of f_count of dmabuf.
*/
drm_gem_object_get(obj);
return obj;
}
}
if (!dev->driver->gem_prime_import_sg_table)
return ERR_PTR(-EINVAL);
attach = dma_buf_attach(dma_buf, attach_dev);
if (IS_ERR(attach))
return ERR_CAST(attach);
get_dma_buf(dma_buf);
sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL);
if (IS_ERR(sgt)) {
ret = PTR_ERR(sgt);
goto fail_detach;
}
obj = dev->driver->gem_prime_import_sg_table(dev, attach, sgt);
if (IS_ERR(obj)) {
ret = PTR_ERR(obj);
goto fail_unmap;
}
obj->import_attach = attach;
return obj;
fail_unmap:
dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL);
fail_detach:
dma_buf_detach(dma_buf, attach);
dma_buf_put(dma_buf);
return ERR_PTR(ret);
}
EXPORT_SYMBOL(drm_gem_prime_import_dev);
/**
* drm_gem_prime_import - helper library implementation of the import callback
* @dev: drm_device to import into
* @dma_buf: dma-buf object to import
*
* This is the implementation of the gem_prime_import functions for GEM drivers
* using the PRIME helpers.
*/
struct drm_gem_object *drm_gem_prime_import(struct drm_device *dev,
struct dma_buf *dma_buf)
{
return drm_gem_prime_import_dev(dev, dma_buf, dev->dev);
}
EXPORT_SYMBOL(drm_gem_prime_import);
/**
* drm_gem_prime_fd_to_handle - PRIME import function for GEM drivers
* @dev: dev to export the buffer from
* @file_priv: drm file-private structure
* @prime_fd: fd id of the dma-buf which should be imported
* @handle: pointer to storage for the handle of the imported buffer object
*
* This is the PRIME import function which must be used mandatorily by GEM
* drivers to ensure correct lifetime management of the underlying GEM object.
* The actual importing of GEM object from the dma-buf is done through the
* gem_import_export driver callback.
*/
int drm_gem_prime_fd_to_handle(struct drm_device *dev,
struct drm_file *file_priv, int prime_fd,
uint32_t *handle)
{
struct dma_buf *dma_buf;
struct drm_gem_object *obj;
int ret;
dma_buf = dma_buf_get(prime_fd);
if (IS_ERR(dma_buf))
return PTR_ERR(dma_buf);
mutex_lock(&file_priv->prime.lock);
ret = drm_prime_lookup_buf_handle(&file_priv->prime,
dma_buf, handle);
if (ret == 0)
goto out_put;
/* never seen this one, need to import */
mutex_lock(&dev->object_name_lock);
if (dev->driver->gem_prime_import)
obj = dev->driver->gem_prime_import(dev, dma_buf);
else
obj = drm_gem_prime_import(dev, dma_buf);
if (IS_ERR(obj)) {
ret = PTR_ERR(obj);
goto out_unlock;
}
if (obj->dma_buf) {
WARN_ON(obj->dma_buf != dma_buf);
} else {
obj->dma_buf = dma_buf;
get_dma_buf(dma_buf);
}
/* _handle_create_tail unconditionally unlocks dev->object_name_lock. */
ret = drm_gem_handle_create_tail(file_priv, obj, handle);
drm_gem_object_put_unlocked(obj);
if (ret)
goto out_put;
ret = drm_prime_add_buf_handle(&file_priv->prime,
dma_buf, *handle);
mutex_unlock(&file_priv->prime.lock);
if (ret)
goto fail;
dma_buf_put(dma_buf);
return 0;
fail:
/* hmm, if driver attached, we are relying on the free-object path
* to detach.. which seems ok..
*/
drm_gem_handle_delete(file_priv, *handle);
dma_buf_put(dma_buf);
return ret;
out_unlock:
mutex_unlock(&dev->object_name_lock);
out_put:
mutex_unlock(&file_priv->prime.lock);
dma_buf_put(dma_buf);
return ret;
}
EXPORT_SYMBOL(drm_gem_prime_fd_to_handle);
int drm_prime_handle_to_fd_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_prime_handle *args = data;
if (!drm_core_check_feature(dev, DRIVER_PRIME))
return -EOPNOTSUPP;
if (!dev->driver->prime_handle_to_fd)
return -ENOSYS;
/* check flags are valid */
if (args->flags & ~(DRM_CLOEXEC | DRM_RDWR))
return -EINVAL;
return dev->driver->prime_handle_to_fd(dev, file_priv,
args->handle, args->flags, &args->fd);
}
int drm_prime_fd_to_handle_ioctl(struct drm_device *dev, void *data,
struct drm_file *file_priv)
{
struct drm_prime_handle *args = data;
if (!drm_core_check_feature(dev, DRIVER_PRIME))
return -EOPNOTSUPP;
if (!dev->driver->prime_fd_to_handle)
return -ENOSYS;
return dev->driver->prime_fd_to_handle(dev, file_priv,
args->fd, &args->handle);
}
/**
* drm_prime_pages_to_sg - converts a page array into an sg list
* @pages: pointer to the array of page pointers to convert
* @nr_pages: length of the page vector
*
* This helper creates an sg table object from a set of pages
* the driver is responsible for mapping the pages into the
* importers address space for use with dma_buf itself.
*/
struct sg_table *drm_prime_pages_to_sg(struct page **pages, unsigned int nr_pages)
{
struct sg_table *sg = NULL;
int ret;
sg = kmalloc(sizeof(struct sg_table), GFP_KERNEL);
if (!sg) {
ret = -ENOMEM;
goto out;
}
ret = sg_alloc_table_from_pages(sg, pages, nr_pages, 0,
nr_pages << PAGE_SHIFT, GFP_KERNEL);
if (ret)
goto out;
return sg;
out:
kfree(sg);
return ERR_PTR(ret);
}
EXPORT_SYMBOL(drm_prime_pages_to_sg);
/**
* drm_prime_sg_to_page_addr_arrays - convert an sg table into a page array
* @sgt: scatter-gather table to convert
* @pages: optional array of page pointers to store the page array in
* @addrs: optional array to store the dma bus address of each page
* @max_entries: size of both the passed-in arrays
*
* Exports an sg table into an array of pages and addresses. This is currently
* required by the TTM driver in order to do correct fault handling.
*/
int drm_prime_sg_to_page_addr_arrays(struct sg_table *sgt, struct page **pages,
dma_addr_t *addrs, int max_entries)
{
unsigned count;
struct scatterlist *sg;
struct page *page;
u32 len, index;
dma_addr_t addr;
index = 0;
for_each_sg(sgt->sgl, sg, sgt->nents, count) {
len = sg->length;
page = sg_page(sg);
addr = sg_dma_address(sg);
while (len > 0) {
if (WARN_ON(index >= max_entries))
return -1;
if (pages)
pages[index] = page;
if (addrs)
addrs[index] = addr;
page++;
addr += PAGE_SIZE;
len -= PAGE_SIZE;
index++;
}
}
return 0;
}
EXPORT_SYMBOL(drm_prime_sg_to_page_addr_arrays);
/**
* drm_prime_gem_destroy - helper to clean up a PRIME-imported GEM object
* @obj: GEM object which was created from a dma-buf
* @sg: the sg-table which was pinned at import time
*
* This is the cleanup functions which GEM drivers need to call when they use
* @drm_gem_prime_import to import dma-bufs.
*/
void drm_prime_gem_destroy(struct drm_gem_object *obj, struct sg_table *sg)
{
struct dma_buf_attachment *attach;
struct dma_buf *dma_buf;
attach = obj->import_attach;
if (sg)
dma_buf_unmap_attachment(attach, sg, DMA_BIDIRECTIONAL);
dma_buf = attach->dmabuf;
dma_buf_detach(attach->dmabuf, attach);
/* remove the reference */
dma_buf_put(dma_buf);
}
EXPORT_SYMBOL(drm_prime_gem_destroy);
void drm_prime_init_file_private(struct drm_prime_file_private *prime_fpriv)
{
mutex_init(&prime_fpriv->lock);
prime_fpriv->dmabufs = RB_ROOT;
prime_fpriv->handles = RB_ROOT;
}
void drm_prime_destroy_file_private(struct drm_prime_file_private *prime_fpriv)
{
/* by now drm_gem_release should've made sure the list is empty */
WARN_ON(!RB_EMPTY_ROOT(&prime_fpriv->dmabufs));
}
