![Chris Wilson](/assets/img/avatar_default.png)
Since commit09ea0dfbf9
("dma-buf: make map_atomic and map function pointers optional"), we no longer need to provide stub no-op functions as the core now provides them directly. References:09ea0dfbf9
("dma-buf: make map_atomic and map function pointers optional") Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Gerd Hoffmann <kraxel@redhat.com> Cc: Alex Deucher <alexander.deucher@amd.com> Cc: "Christian König" <christian.koenig@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20180807174748.4503-1-chris@chris-wilson.co.uk
954 lines
26 KiB
C
954 lines
26 KiB
C
/*
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* Copyright © 2012 Red Hat
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*
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* Permission is hereby granted, free of charge, to any person obtaining a
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* copy of this software and associated documentation files (the "Software"),
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* to deal in the Software without restriction, including without limitation
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* the rights to use, copy, modify, merge, publish, distribute, sublicense,
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* and/or sell copies of the Software, and to permit persons to whom the
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* Software is furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice (including the next
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* paragraph) shall be included in all copies or substantial portions of the
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* Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
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* IN THE SOFTWARE.
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*
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* Authors:
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* Dave Airlie <airlied@redhat.com>
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* Rob Clark <rob.clark@linaro.org>
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*
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*/
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#include <linux/export.h>
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#include <linux/dma-buf.h>
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#include <linux/rbtree.h>
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#include <drm/drm_prime.h>
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#include <drm/drm_gem.h>
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#include <drm/drmP.h>
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#include "drm_internal.h"
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/*
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* DMA-BUF/GEM Object references and lifetime overview:
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*
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* On the export the dma_buf holds a reference to the exporting GEM
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* object. It takes this reference in handle_to_fd_ioctl, when it
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* first calls .prime_export and stores the exporting GEM object in
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* the dma_buf priv. This reference needs to be released when the
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* final reference to the &dma_buf itself is dropped and its
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* &dma_buf_ops.release function is called. For GEM-based drivers,
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* the dma_buf should be exported using drm_gem_dmabuf_export() and
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* then released by drm_gem_dmabuf_release().
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*
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* On the import the importing GEM object holds a reference to the
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* dma_buf (which in turn holds a ref to the exporting GEM object).
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* It takes that reference in the fd_to_handle ioctl.
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* It calls dma_buf_get, creates an attachment to it and stores the
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* attachment in the GEM object. When this attachment is destroyed
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* when the imported object is destroyed, we remove the attachment
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* and drop the reference to the dma_buf.
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*
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* When all the references to the &dma_buf are dropped, i.e. when
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* userspace has closed both handles to the imported GEM object (through the
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* FD_TO_HANDLE IOCTL) and closed the file descriptor of the exported
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* (through the HANDLE_TO_FD IOCTL) dma_buf, and all kernel-internal references
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* are also gone, then the dma_buf gets destroyed. This can also happen as a
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* part of the clean up procedure in the drm_release() function if userspace
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* fails to properly clean up. Note that both the kernel and userspace (by
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* keeeping the PRIME file descriptors open) can hold references onto a
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* &dma_buf.
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*
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* Thus the chain of references always flows in one direction
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* (avoiding loops): importing_gem -> dmabuf -> exporting_gem
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*
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* Self-importing: if userspace is using PRIME as a replacement for flink
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* then it will get a fd->handle request for a GEM object that it created.
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* Drivers should detect this situation and return back the gem object
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* from the dma-buf private. Prime will do this automatically for drivers that
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* use the drm_gem_prime_{import,export} helpers.
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*
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* GEM struct &dma_buf_ops symbols are now exported. They can be resued by
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* drivers which implement GEM interface.
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*/
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struct drm_prime_member {
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struct dma_buf *dma_buf;
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uint32_t handle;
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struct rb_node dmabuf_rb;
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struct rb_node handle_rb;
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};
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struct drm_prime_attachment {
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struct sg_table *sgt;
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enum dma_data_direction dir;
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};
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static int drm_prime_add_buf_handle(struct drm_prime_file_private *prime_fpriv,
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struct dma_buf *dma_buf, uint32_t handle)
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{
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struct drm_prime_member *member;
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struct rb_node **p, *rb;
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member = kmalloc(sizeof(*member), GFP_KERNEL);
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if (!member)
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return -ENOMEM;
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get_dma_buf(dma_buf);
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member->dma_buf = dma_buf;
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member->handle = handle;
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rb = NULL;
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p = &prime_fpriv->dmabufs.rb_node;
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while (*p) {
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struct drm_prime_member *pos;
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rb = *p;
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pos = rb_entry(rb, struct drm_prime_member, dmabuf_rb);
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if (dma_buf > pos->dma_buf)
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p = &rb->rb_right;
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else
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p = &rb->rb_left;
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}
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rb_link_node(&member->dmabuf_rb, rb, p);
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rb_insert_color(&member->dmabuf_rb, &prime_fpriv->dmabufs);
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rb = NULL;
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p = &prime_fpriv->handles.rb_node;
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while (*p) {
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struct drm_prime_member *pos;
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rb = *p;
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pos = rb_entry(rb, struct drm_prime_member, handle_rb);
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if (handle > pos->handle)
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p = &rb->rb_right;
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else
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p = &rb->rb_left;
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}
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rb_link_node(&member->handle_rb, rb, p);
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rb_insert_color(&member->handle_rb, &prime_fpriv->handles);
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return 0;
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}
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static struct dma_buf *drm_prime_lookup_buf_by_handle(struct drm_prime_file_private *prime_fpriv,
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uint32_t handle)
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{
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struct rb_node *rb;
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rb = prime_fpriv->handles.rb_node;
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while (rb) {
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struct drm_prime_member *member;
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member = rb_entry(rb, struct drm_prime_member, handle_rb);
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if (member->handle == handle)
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return member->dma_buf;
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else if (member->handle < handle)
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rb = rb->rb_right;
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else
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rb = rb->rb_left;
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}
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return NULL;
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}
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static int drm_prime_lookup_buf_handle(struct drm_prime_file_private *prime_fpriv,
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struct dma_buf *dma_buf,
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uint32_t *handle)
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{
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struct rb_node *rb;
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rb = prime_fpriv->dmabufs.rb_node;
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while (rb) {
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struct drm_prime_member *member;
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member = rb_entry(rb, struct drm_prime_member, dmabuf_rb);
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if (member->dma_buf == dma_buf) {
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*handle = member->handle;
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return 0;
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} else if (member->dma_buf < dma_buf) {
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rb = rb->rb_right;
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} else {
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rb = rb->rb_left;
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}
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}
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return -ENOENT;
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}
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/**
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* drm_gem_map_attach - dma_buf attach implementation for GEM
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* @dma_buf: buffer to attach device to
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* @attach: buffer attachment data
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*
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* Allocates &drm_prime_attachment and calls &drm_driver.gem_prime_pin for
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* device specific attachment. This can be used as the &dma_buf_ops.attach
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* callback.
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*
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* Returns 0 on success, negative error code on failure.
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*/
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int drm_gem_map_attach(struct dma_buf *dma_buf,
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struct dma_buf_attachment *attach)
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{
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struct drm_prime_attachment *prime_attach;
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struct drm_gem_object *obj = dma_buf->priv;
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struct drm_device *dev = obj->dev;
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prime_attach = kzalloc(sizeof(*prime_attach), GFP_KERNEL);
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if (!prime_attach)
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return -ENOMEM;
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prime_attach->dir = DMA_NONE;
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attach->priv = prime_attach;
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if (!dev->driver->gem_prime_pin)
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return 0;
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return dev->driver->gem_prime_pin(obj);
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}
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EXPORT_SYMBOL(drm_gem_map_attach);
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/**
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* drm_gem_map_detach - dma_buf detach implementation for GEM
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* @dma_buf: buffer to detach from
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* @attach: attachment to be detached
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*
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* Cleans up &dma_buf_attachment. This can be used as the &dma_buf_ops.detach
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* callback.
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*/
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void drm_gem_map_detach(struct dma_buf *dma_buf,
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struct dma_buf_attachment *attach)
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{
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struct drm_prime_attachment *prime_attach = attach->priv;
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struct drm_gem_object *obj = dma_buf->priv;
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struct drm_device *dev = obj->dev;
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if (prime_attach) {
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struct sg_table *sgt = prime_attach->sgt;
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if (sgt) {
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if (prime_attach->dir != DMA_NONE)
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dma_unmap_sg_attrs(attach->dev, sgt->sgl,
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sgt->nents,
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prime_attach->dir,
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DMA_ATTR_SKIP_CPU_SYNC);
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sg_free_table(sgt);
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}
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kfree(sgt);
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kfree(prime_attach);
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attach->priv = NULL;
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}
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if (dev->driver->gem_prime_unpin)
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dev->driver->gem_prime_unpin(obj);
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}
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EXPORT_SYMBOL(drm_gem_map_detach);
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void drm_prime_remove_buf_handle_locked(struct drm_prime_file_private *prime_fpriv,
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struct dma_buf *dma_buf)
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{
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struct rb_node *rb;
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rb = prime_fpriv->dmabufs.rb_node;
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while (rb) {
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struct drm_prime_member *member;
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member = rb_entry(rb, struct drm_prime_member, dmabuf_rb);
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if (member->dma_buf == dma_buf) {
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rb_erase(&member->handle_rb, &prime_fpriv->handles);
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rb_erase(&member->dmabuf_rb, &prime_fpriv->dmabufs);
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dma_buf_put(dma_buf);
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kfree(member);
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return;
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} else if (member->dma_buf < dma_buf) {
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rb = rb->rb_right;
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} else {
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rb = rb->rb_left;
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}
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}
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}
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/**
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* drm_gem_map_dma_buf - map_dma_buf implementation for GEM
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* @attach: attachment whose scatterlist is to be returned
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* @dir: direction of DMA transfer
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*
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* Calls &drm_driver.gem_prime_get_sg_table and then maps the scatterlist. This
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* can be used as the &dma_buf_ops.map_dma_buf callback.
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*
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* Returns sg_table containing the scatterlist to be returned; returns ERR_PTR
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* on error. May return -EINTR if it is interrupted by a signal.
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*/
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struct sg_table *drm_gem_map_dma_buf(struct dma_buf_attachment *attach,
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enum dma_data_direction dir)
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{
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struct drm_prime_attachment *prime_attach = attach->priv;
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struct drm_gem_object *obj = attach->dmabuf->priv;
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struct sg_table *sgt;
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if (WARN_ON(dir == DMA_NONE || !prime_attach))
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return ERR_PTR(-EINVAL);
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/* return the cached mapping when possible */
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if (prime_attach->dir == dir)
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return prime_attach->sgt;
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/*
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* two mappings with different directions for the same attachment are
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* not allowed
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*/
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if (WARN_ON(prime_attach->dir != DMA_NONE))
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return ERR_PTR(-EBUSY);
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sgt = obj->dev->driver->gem_prime_get_sg_table(obj);
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if (!IS_ERR(sgt)) {
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if (!dma_map_sg_attrs(attach->dev, sgt->sgl, sgt->nents, dir,
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DMA_ATTR_SKIP_CPU_SYNC)) {
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sg_free_table(sgt);
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kfree(sgt);
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sgt = ERR_PTR(-ENOMEM);
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} else {
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prime_attach->sgt = sgt;
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prime_attach->dir = dir;
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}
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}
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return sgt;
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}
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EXPORT_SYMBOL(drm_gem_map_dma_buf);
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/**
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* drm_gem_unmap_dma_buf - unmap_dma_buf implementation for GEM
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* @attach: attachment to unmap buffer from
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* @sgt: scatterlist info of the buffer to unmap
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* @dir: direction of DMA transfer
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*
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* Not implemented. The unmap is done at drm_gem_map_detach(). This can be
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* used as the &dma_buf_ops.unmap_dma_buf callback.
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*/
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void drm_gem_unmap_dma_buf(struct dma_buf_attachment *attach,
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struct sg_table *sgt,
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enum dma_data_direction dir)
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{
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/* nothing to be done here */
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}
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EXPORT_SYMBOL(drm_gem_unmap_dma_buf);
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/**
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* drm_gem_dmabuf_export - dma_buf export implementation for GEM
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* @dev: parent device for the exported dmabuf
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* @exp_info: the export information used by dma_buf_export()
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*
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* This wraps dma_buf_export() for use by generic GEM drivers that are using
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* drm_gem_dmabuf_release(). In addition to calling dma_buf_export(), we take
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* a reference to the &drm_device and the exported &drm_gem_object (stored in
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* &dma_buf_export_info.priv) which is released by drm_gem_dmabuf_release().
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*
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* Returns the new dmabuf.
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*/
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struct dma_buf *drm_gem_dmabuf_export(struct drm_device *dev,
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struct dma_buf_export_info *exp_info)
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{
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struct dma_buf *dma_buf;
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dma_buf = dma_buf_export(exp_info);
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if (IS_ERR(dma_buf))
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return dma_buf;
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drm_dev_get(dev);
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drm_gem_object_get(exp_info->priv);
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return dma_buf;
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}
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EXPORT_SYMBOL(drm_gem_dmabuf_export);
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/**
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* drm_gem_dmabuf_release - dma_buf release implementation for GEM
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* @dma_buf: buffer to be released
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*
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* Generic release function for dma_bufs exported as PRIME buffers. GEM drivers
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* must use this in their dma_buf ops structure as the release callback.
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* drm_gem_dmabuf_release() should be used in conjunction with
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* drm_gem_dmabuf_export().
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*/
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void drm_gem_dmabuf_release(struct dma_buf *dma_buf)
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{
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struct drm_gem_object *obj = dma_buf->priv;
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struct drm_device *dev = obj->dev;
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/* drop the reference on the export fd holds */
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drm_gem_object_put_unlocked(obj);
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drm_dev_put(dev);
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}
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EXPORT_SYMBOL(drm_gem_dmabuf_release);
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/**
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* drm_gem_dmabuf_vmap - dma_buf vmap implementation for GEM
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* @dma_buf: buffer to be mapped
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*
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* Sets up a kernel virtual mapping. This can be used as the &dma_buf_ops.vmap
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* callback.
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*
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* Returns the kernel virtual address.
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*/
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void *drm_gem_dmabuf_vmap(struct dma_buf *dma_buf)
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{
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struct drm_gem_object *obj = dma_buf->priv;
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struct drm_device *dev = obj->dev;
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if (dev->driver->gem_prime_vmap)
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return dev->driver->gem_prime_vmap(obj);
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else
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return NULL;
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}
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EXPORT_SYMBOL(drm_gem_dmabuf_vmap);
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/**
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* drm_gem_dmabuf_vunmap - dma_buf vunmap implementation for GEM
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* @dma_buf: buffer to be unmapped
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* @vaddr: the virtual address of the buffer
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*
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* Releases a kernel virtual mapping. This can be used as the
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* &dma_buf_ops.vunmap callback.
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*/
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void drm_gem_dmabuf_vunmap(struct dma_buf *dma_buf, void *vaddr)
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{
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struct drm_gem_object *obj = dma_buf->priv;
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struct drm_device *dev = obj->dev;
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if (dev->driver->gem_prime_vunmap)
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dev->driver->gem_prime_vunmap(obj, vaddr);
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}
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EXPORT_SYMBOL(drm_gem_dmabuf_vunmap);
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/**
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* drm_gem_dmabuf_mmap - dma_buf mmap implementation for GEM
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* @dma_buf: buffer to be mapped
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* @vma: virtual address range
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*
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* Provides memory mapping for the buffer. This can be used as the
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* &dma_buf_ops.mmap callback.
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*
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* Returns 0 on success or a negative error code on failure.
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*/
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int drm_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma)
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{
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struct drm_gem_object *obj = dma_buf->priv;
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struct drm_device *dev = obj->dev;
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if (!dev->driver->gem_prime_mmap)
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return -ENOSYS;
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return dev->driver->gem_prime_mmap(obj, vma);
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}
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EXPORT_SYMBOL(drm_gem_dmabuf_mmap);
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static const struct dma_buf_ops drm_gem_prime_dmabuf_ops = {
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.attach = drm_gem_map_attach,
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.detach = drm_gem_map_detach,
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.map_dma_buf = drm_gem_map_dma_buf,
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.unmap_dma_buf = drm_gem_unmap_dma_buf,
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.release = drm_gem_dmabuf_release,
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.mmap = drm_gem_dmabuf_mmap,
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.vmap = drm_gem_dmabuf_vmap,
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.vunmap = drm_gem_dmabuf_vunmap,
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};
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/**
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* DOC: PRIME Helpers
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*
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* Drivers can implement @gem_prime_export and @gem_prime_import in terms of
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* simpler APIs by using the helper functions @drm_gem_prime_export and
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* @drm_gem_prime_import. These functions implement dma-buf support in terms of
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* 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,
|
|
};
|
|
|
|
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;
|
|
}
|
|
|
|
dmabuf = dev->driver->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_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);
|
|
obj = dev->driver->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));
|
|
}
|