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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/gpu/drm/drm_gem_cma_helper.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpu/drm/drm_gem_cma_helper.c')
-rw-r--r--drivers/gpu/drm/drm_gem_cma_helper.c639
1 files changed, 639 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_gem_cma_helper.c b/drivers/gpu/drm/drm_gem_cma_helper.c
new file mode 100644
index 000000000..59b9ca207
--- /dev/null
+++ b/drivers/gpu/drm/drm_gem_cma_helper.c
@@ -0,0 +1,639 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 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.
+ */
+
+#include <linux/dma-buf.h>
+#include <linux/dma-mapping.h>
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+
+#include <drm/drm.h>
+#include <drm/drm_device.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_vma_manager.h>
+
+/**
+ * DOC: cma helpers
+ *
+ * The Contiguous Memory Allocator reserves a pool of memory at early boot
+ * that is used to service requests for large blocks of contiguous memory.
+ *
+ * The DRM GEM/CMA helpers use this allocator as a means to provide buffer
+ * objects that are physically contiguous in memory. This is useful for
+ * display drivers that are unable to map scattered buffers via an IOMMU.
+ */
+
+/**
+ * __drm_gem_cma_create - Create a GEM CMA object without allocating memory
+ * @drm: DRM device
+ * @size: size of the object to allocate
+ *
+ * This function creates and initializes a GEM CMA object of the given size,
+ * but doesn't allocate any memory to back the object.
+ *
+ * Returns:
+ * A struct drm_gem_cma_object * on success or an ERR_PTR()-encoded negative
+ * error code on failure.
+ */
+static struct drm_gem_cma_object *
+__drm_gem_cma_create(struct drm_device *drm, size_t size)
+{
+ struct drm_gem_cma_object *cma_obj;
+ struct drm_gem_object *gem_obj;
+ int ret;
+
+ if (drm->driver->gem_create_object)
+ gem_obj = drm->driver->gem_create_object(drm, size);
+ else
+ gem_obj = kzalloc(sizeof(*cma_obj), GFP_KERNEL);
+ if (!gem_obj)
+ return ERR_PTR(-ENOMEM);
+ cma_obj = container_of(gem_obj, struct drm_gem_cma_object, 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
+ * @drm: DRM device
+ * @size: size of the object to allocate
+ *
+ * This function creates a CMA GEM object and allocates a contiguous chunk of
+ * memory as backing store. The backing memory has the writecombine attribute
+ * set.
+ *
+ * Returns:
+ * A struct drm_gem_cma_object * on success or an ERR_PTR()-encoded negative
+ * error code on failure.
+ */
+struct drm_gem_cma_object *drm_gem_cma_create(struct drm_device *drm,
+ size_t size)
+{
+ struct drm_gem_cma_object *cma_obj;
+ 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_wc(drm->dev, size, &cma_obj->paddr,
+ GFP_KERNEL | __GFP_NOWARN);
+ if (!cma_obj->vaddr) {
+ drm_dbg(drm, "failed to allocate buffer with size %zu\n",
+ size);
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ return cma_obj;
+
+error:
+ drm_gem_object_put(&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
+ * return a GEM handle to it
+ * @file_priv: DRM file-private structure to register the handle for
+ * @drm: DRM device
+ * @size: size of the object to allocate
+ * @handle: return location for the GEM handle
+ *
+ * This function creates a CMA GEM object, allocating a physically contiguous
+ * chunk of memory as backing store. The GEM object is then added to the list
+ * of object associated with the given file and a handle to it is returned.
+ *
+ * Returns:
+ * A struct drm_gem_cma_object * on success or an ERR_PTR()-encoded negative
+ * error code on failure.
+ */
+static struct drm_gem_cma_object *
+drm_gem_cma_create_with_handle(struct drm_file *file_priv,
+ struct drm_device *drm, size_t size,
+ uint32_t *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);
+ /* drop reference from allocate - handle holds it now. */
+ drm_gem_object_put(gem_obj);
+ if (ret)
+ return ERR_PTR(ret);
+
+ return cma_obj;
+}
+
+/**
+ * drm_gem_cma_free_object - free resources associated with a CMA GEM object
+ * @gem_obj: GEM object to free
+ *
+ * This function frees the backing memory of the CMA GEM object, cleans up the
+ * GEM object state and frees the memory used to store the object itself.
+ * If the buffer is imported and the virtual address is set, it is released.
+ * Drivers using the CMA helpers should set this as their
+ * &drm_driver.gem_free_object_unlocked callback.
+ */
+void drm_gem_cma_free_object(struct drm_gem_object *gem_obj)
+{
+ struct drm_gem_cma_object *cma_obj;
+
+ cma_obj = to_drm_gem_cma_obj(gem_obj);
+
+ if (gem_obj->import_attach) {
+ if (cma_obj->vaddr)
+ dma_buf_vunmap(gem_obj->import_attach->dmabuf, cma_obj->vaddr);
+ drm_prime_gem_destroy(gem_obj, cma_obj->sgt);
+ } else if (cma_obj->vaddr) {
+ dma_free_wc(gem_obj->dev->dev, cma_obj->base.size,
+ cma_obj->vaddr, cma_obj->paddr);
+ }
+
+ drm_gem_object_release(gem_obj);
+
+ kfree(cma_obj);
+}
+EXPORT_SYMBOL_GPL(drm_gem_cma_free_object);
+
+/**
+ * drm_gem_cma_dumb_create_internal - create a dumb buffer object
+ * @file_priv: DRM file-private structure to create the dumb buffer for
+ * @drm: DRM device
+ * @args: IOCTL data
+ *
+ * This aligns the pitch and size arguments to the minimum required. This is
+ * an internal helper that can be wrapped by a driver to account for hardware
+ * with more specific alignment requirements. It should not be used directly
+ * as their &drm_driver.dumb_create callback.
+ *
+ * Returns:
+ * 0 on success or a negative error code on failure.
+ */
+int drm_gem_cma_dumb_create_internal(struct drm_file *file_priv,
+ struct drm_device *drm,
+ struct drm_mode_create_dumb *args)
+{
+ unsigned int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
+ struct drm_gem_cma_object *cma_obj;
+
+ 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, drm, args->size,
+ &args->handle);
+ return PTR_ERR_OR_ZERO(cma_obj);
+}
+EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_create_internal);
+
+/**
+ * drm_gem_cma_dumb_create - create a dumb buffer object
+ * @file_priv: DRM file-private structure to create the dumb buffer for
+ * @drm: DRM device
+ * @args: IOCTL data
+ *
+ * This function computes the pitch of the dumb buffer and rounds it up to an
+ * integer number of bytes per pixel. Drivers for hardware that doesn't have
+ * any additional restrictions on the pitch can directly use this function as
+ * their &drm_driver.dumb_create callback.
+ *
+ * For hardware with additional restrictions, drivers can adjust the fields
+ * set up by userspace and pass the IOCTL data along to the
+ * drm_gem_cma_dumb_create_internal() function.
+ *
+ * Returns:
+ * 0 on success or a negative error code on failure.
+ */
+int drm_gem_cma_dumb_create(struct drm_file *file_priv,
+ struct drm_device *drm,
+ struct drm_mode_create_dumb *args)
+{
+ struct drm_gem_cma_object *cma_obj;
+
+ args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
+ args->size = args->pitch * args->height;
+
+ cma_obj = drm_gem_cma_create_with_handle(file_priv, drm, args->size,
+ &args->handle);
+ return PTR_ERR_OR_ZERO(cma_obj);
+}
+EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_create);
+
+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;
+
+ /*
+ * Clear the VM_PFNMAP flag that was set by drm_gem_mmap(), and set the
+ * vm_pgoff (used as a fake buffer offset by DRM) to 0 as we want to map
+ * the whole buffer.
+ */
+ vma->vm_flags &= ~VM_PFNMAP;
+ vma->vm_pgoff = 0;
+
+ ret = dma_mmap_wc(cma_obj->base.dev->dev, vma, cma_obj->vaddr,
+ cma_obj->paddr, vma->vm_end - vma->vm_start);
+ if (ret)
+ drm_gem_vm_close(vma);
+
+ return ret;
+}
+
+/**
+ * drm_gem_cma_mmap - memory-map a CMA GEM object
+ * @filp: file object
+ * @vma: VMA for the area to be mapped
+ *
+ * This function implements an augmented version of the GEM DRM file mmap
+ * operation for CMA objects: In addition to the usual GEM VMA setup it
+ * immediately faults in the entire object instead of using on-demaind
+ * faulting. Drivers which employ the CMA helpers should use this function
+ * as their ->mmap() handler in the DRM device file's file_operations
+ * structure.
+ *
+ * Instead of directly referencing this function, drivers should use the
+ * DEFINE_DRM_GEM_CMA_FOPS().macro.
+ *
+ * Returns:
+ * 0 on success or a negative error code on failure.
+ */
+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);
+
+#ifndef CONFIG_MMU
+/**
+ * drm_gem_cma_get_unmapped_area - propose address for mapping in noMMU cases
+ * @filp: file object
+ * @addr: memory address
+ * @len: buffer size
+ * @pgoff: page offset
+ * @flags: memory flags
+ *
+ * This function is used in noMMU platforms to propose address mapping
+ * for a given buffer.
+ * It's intended to be used as a direct handler for the struct
+ * &file_operations.get_unmapped_area operation.
+ *
+ * Returns:
+ * mapping address on success or a negative error code on failure.
+ */
+unsigned long drm_gem_cma_get_unmapped_area(struct file *filp,
+ unsigned long addr,
+ unsigned long len,
+ unsigned long pgoff,
+ unsigned long flags)
+{
+ struct drm_gem_cma_object *cma_obj;
+ struct drm_gem_object *obj = NULL;
+ struct drm_file *priv = filp->private_data;
+ struct drm_device *dev = priv->minor->dev;
+ struct drm_vma_offset_node *node;
+
+ if (drm_dev_is_unplugged(dev))
+ return -ENODEV;
+
+ drm_vma_offset_lock_lookup(dev->vma_offset_manager);
+ node = drm_vma_offset_exact_lookup_locked(dev->vma_offset_manager,
+ pgoff,
+ len >> PAGE_SHIFT);
+ if (likely(node)) {
+ obj = container_of(node, struct drm_gem_object, vma_node);
+ /*
+ * When the object is being freed, after it hits 0-refcnt it
+ * proceeds to tear down the object. In the process it will
+ * attempt to remove the VMA offset and so acquire this
+ * mgr->vm_lock. Therefore if we find an object with a 0-refcnt
+ * that matches our range, we know it is in the process of being
+ * destroyed and will be freed as soon as we release the lock -
+ * so we have to check for the 0-refcnted object and treat it as
+ * invalid.
+ */
+ if (!kref_get_unless_zero(&obj->refcount))
+ obj = NULL;
+ }
+
+ drm_vma_offset_unlock_lookup(dev->vma_offset_manager);
+
+ if (!obj)
+ return -EINVAL;
+
+ if (!drm_vma_node_is_allowed(node, priv)) {
+ drm_gem_object_put(obj);
+ return -EACCES;
+ }
+
+ cma_obj = to_drm_gem_cma_obj(obj);
+
+ drm_gem_object_put(obj);
+
+ return cma_obj->vaddr ? (unsigned long)cma_obj->vaddr : -EINVAL;
+}
+EXPORT_SYMBOL_GPL(drm_gem_cma_get_unmapped_area);
+#endif
+
+/**
+ * drm_gem_cma_print_info() - Print &drm_gem_cma_object info for debugfs
+ * @p: DRM printer
+ * @indent: Tab indentation level
+ * @obj: GEM object
+ *
+ * This function can be used as the &drm_driver->gem_print_info callback.
+ * It prints paddr and vaddr for use in e.g. debugfs output.
+ */
+void drm_gem_cma_print_info(struct drm_printer *p, unsigned int indent,
+ const struct drm_gem_object *obj)
+{
+ const struct drm_gem_cma_object *cma_obj = to_drm_gem_cma_obj(obj);
+
+ drm_printf_indent(p, indent, "paddr=%pad\n", &cma_obj->paddr);
+ drm_printf_indent(p, indent, "vaddr=%p\n", cma_obj->vaddr);
+}
+EXPORT_SYMBOL(drm_gem_cma_print_info);
+
+/**
+ * drm_gem_cma_prime_get_sg_table - provide a scatter/gather table of pinned
+ * pages for a CMA GEM object
+ * @obj: GEM object
+ *
+ * This function exports a scatter/gather table suitable for PRIME usage by
+ * calling the standard DMA mapping API. Drivers using the CMA helpers should
+ * set this as their &drm_driver.gem_prime_get_sg_table callback.
+ *
+ * Returns:
+ * A pointer to the scatter/gather table of pinned pages or NULL on failure.
+ */
+struct sg_table *drm_gem_cma_prime_get_sg_table(struct drm_gem_object *obj)
+{
+ struct drm_gem_cma_object *cma_obj = to_drm_gem_cma_obj(obj);
+ struct sg_table *sgt;
+ int ret;
+
+ sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
+ if (!sgt)
+ return ERR_PTR(-ENOMEM);
+
+ ret = dma_get_sgtable(obj->dev->dev, sgt, cma_obj->vaddr,
+ cma_obj->paddr, obj->size);
+ if (ret < 0)
+ goto out;
+
+ return sgt;
+
+out:
+ kfree(sgt);
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL_GPL(drm_gem_cma_prime_get_sg_table);
+
+/**
+ * drm_gem_cma_prime_import_sg_table - produce a CMA GEM object from another
+ * driver's scatter/gather table of pinned pages
+ * @dev: device to import into
+ * @attach: DMA-BUF attachment
+ * @sgt: scatter/gather table of pinned pages
+ *
+ * This function imports a scatter/gather table exported via DMA-BUF by
+ * another driver. Imported buffers must be physically contiguous in memory
+ * (i.e. the scatter/gather table must contain a single entry). Drivers that
+ * use the CMA helpers should set this as their
+ * &drm_driver.gem_prime_import_sg_table callback.
+ *
+ * Returns:
+ * A pointer to a newly created GEM object or an ERR_PTR-encoded negative
+ * error code on failure.
+ */
+struct drm_gem_object *
+drm_gem_cma_prime_import_sg_table(struct drm_device *dev,
+ struct dma_buf_attachment *attach,
+ struct sg_table *sgt)
+{
+ struct drm_gem_cma_object *cma_obj;
+
+ /* check if the entries in the sg_table are contiguous */
+ if (drm_prime_get_contiguous_size(sgt) < attach->dmabuf->size)
+ return ERR_PTR(-EINVAL);
+
+ /* Create a CMA GEM buffer. */
+ cma_obj = __drm_gem_cma_create(dev, attach->dmabuf->size);
+ if (IS_ERR(cma_obj))
+ return ERR_CAST(cma_obj);
+
+ cma_obj->paddr = sg_dma_address(sgt->sgl);
+ cma_obj->sgt = sgt;
+
+ DRM_DEBUG_PRIME("dma_addr = %pad, size = %zu\n", &cma_obj->paddr, attach->dmabuf->size);
+
+ return &cma_obj->base;
+}
+EXPORT_SYMBOL_GPL(drm_gem_cma_prime_import_sg_table);
+
+/**
+ * drm_gem_cma_prime_mmap - memory-map an exported CMA GEM object
+ * @obj: GEM object
+ * @vma: VMA for the area to be mapped
+ *
+ * This function maps a buffer imported via DRM PRIME into a userspace
+ * process's address space. Drivers that use the CMA helpers should set this
+ * as their &drm_driver.gem_prime_mmap callback.
+ *
+ * Returns:
+ * 0 on success or a negative error code on failure.
+ */
+int drm_gem_cma_prime_mmap(struct drm_gem_object *obj,
+ struct vm_area_struct *vma)
+{
+ struct drm_gem_cma_object *cma_obj;
+ int ret;
+
+ ret = drm_gem_mmap_obj(obj, obj->size, vma);
+ if (ret < 0)
+ return ret;
+
+ cma_obj = to_drm_gem_cma_obj(obj);
+ return drm_gem_cma_mmap_obj(cma_obj, vma);
+}
+EXPORT_SYMBOL_GPL(drm_gem_cma_prime_mmap);
+
+/**
+ * drm_gem_cma_prime_vmap - map a CMA GEM object into the kernel's virtual
+ * address space
+ * @obj: GEM object
+ *
+ * This function maps a buffer exported via DRM PRIME into the kernel's
+ * virtual address space. Since the CMA buffers are already mapped into the
+ * kernel virtual address space this simply returns the cached virtual
+ * address. Drivers using the CMA helpers should set this as their DRM
+ * driver's &drm_driver.gem_prime_vmap callback.
+ *
+ * Returns:
+ * The kernel virtual address of the CMA GEM object's backing store.
+ */
+void *drm_gem_cma_prime_vmap(struct drm_gem_object *obj)
+{
+ struct drm_gem_cma_object *cma_obj = to_drm_gem_cma_obj(obj);
+
+ return cma_obj->vaddr;
+}
+EXPORT_SYMBOL_GPL(drm_gem_cma_prime_vmap);
+
+/**
+ * drm_gem_cma_prime_vunmap - unmap a CMA GEM object from the kernel's virtual
+ * address space
+ * @obj: GEM object
+ * @vaddr: kernel virtual address where the CMA GEM object was mapped
+ *
+ * This function removes a buffer exported via DRM PRIME from the kernel's
+ * virtual address space. This is a no-op because CMA buffers cannot be
+ * unmapped from kernel space. Drivers using the CMA helpers should set this
+ * as their &drm_driver.gem_prime_vunmap callback.
+ */
+void drm_gem_cma_prime_vunmap(struct drm_gem_object *obj, void *vaddr)
+{
+ /* Nothing to do */
+}
+EXPORT_SYMBOL_GPL(drm_gem_cma_prime_vunmap);
+
+static const struct drm_gem_object_funcs drm_gem_cma_default_funcs = {
+ .free = drm_gem_cma_free_object,
+ .print_info = drm_gem_cma_print_info,
+ .get_sg_table = drm_gem_cma_prime_get_sg_table,
+ .vmap = drm_gem_cma_prime_vmap,
+ .vm_ops = &drm_gem_cma_vm_ops,
+};
+
+/**
+ * drm_gem_cma_create_object_default_funcs - Create a CMA GEM object with a
+ * default function table
+ * @dev: DRM device
+ * @size: Size of the object to allocate
+ *
+ * This sets the GEM object functions to the default CMA helper functions.
+ * This function can be used as the &drm_driver.gem_create_object callback.
+ *
+ * Returns:
+ * A pointer to a allocated GEM object or an error pointer on failure.
+ */
+struct drm_gem_object *
+drm_gem_cma_create_object_default_funcs(struct drm_device *dev, size_t size)
+{
+ struct drm_gem_cma_object *cma_obj;
+
+ cma_obj = kzalloc(sizeof(*cma_obj), GFP_KERNEL);
+ if (!cma_obj)
+ return NULL;
+
+ cma_obj->base.funcs = &drm_gem_cma_default_funcs;
+
+ return &cma_obj->base;
+}
+EXPORT_SYMBOL(drm_gem_cma_create_object_default_funcs);
+
+/**
+ * drm_gem_cma_prime_import_sg_table_vmap - PRIME import another driver's
+ * scatter/gather table and get the virtual address of the buffer
+ * @dev: DRM device
+ * @attach: DMA-BUF attachment
+ * @sgt: Scatter/gather table of pinned pages
+ *
+ * This function imports a scatter/gather table using
+ * drm_gem_cma_prime_import_sg_table() and uses dma_buf_vmap() to get the kernel
+ * virtual address. This ensures that a CMA GEM object always has its virtual
+ * address set. This address is released when the object is freed.
+ *
+ * This function can be used as the &drm_driver.gem_prime_import_sg_table
+ * callback. The &DRM_GEM_CMA_DRIVER_OPS_VMAP macro provides a shortcut to set
+ * the necessary DRM driver operations.
+ *
+ * Returns:
+ * A pointer to a newly created GEM object or an ERR_PTR-encoded negative
+ * error code on failure.
+ */
+struct drm_gem_object *
+drm_gem_cma_prime_import_sg_table_vmap(struct drm_device *dev,
+ struct dma_buf_attachment *attach,
+ struct sg_table *sgt)
+{
+ struct drm_gem_cma_object *cma_obj;
+ struct drm_gem_object *obj;
+ void *vaddr;
+
+ vaddr = dma_buf_vmap(attach->dmabuf);
+ if (!vaddr) {
+ DRM_ERROR("Failed to vmap PRIME buffer\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ obj = drm_gem_cma_prime_import_sg_table(dev, attach, sgt);
+ if (IS_ERR(obj)) {
+ dma_buf_vunmap(attach->dmabuf, vaddr);
+ return obj;
+ }
+
+ cma_obj = to_drm_gem_cma_obj(obj);
+ cma_obj->vaddr = vaddr;
+
+ return obj;
+}
+EXPORT_SYMBOL(drm_gem_cma_prime_import_sg_table_vmap);