#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/export.h>
+#include <linux/dma-buf.h>
#include <linux/dma-mapping.h>
#include <drm/drmP.h>
#include <drm/drm.h>
#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_vma_manager.h>
-static unsigned int get_gem_mmap_offset(struct drm_gem_object *obj)
-{
- return (unsigned int)obj->map_list.hash.key << PAGE_SHIFT;
-}
-
-static void drm_gem_cma_buf_destroy(struct drm_device *drm,
- struct drm_gem_cma_object *cma_obj)
-{
- dma_free_writecombine(drm->dev, cma_obj->base.size, cma_obj->vaddr,
- cma_obj->paddr);
-}
+/**
+ * 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 - allocate an object with the given size
+/**
+ * __drm_gem_cma_create - Create a GEM CMA object without allocating memory
+ * @drm: DRM device
+ * @size: size of the object to allocate
*
- * returns a struct drm_gem_cma_object* on success or ERR_PTR values
- * on failure.
+ * 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.
*/
-struct drm_gem_cma_object *drm_gem_cma_create(struct drm_device *drm,
- unsigned int size)
+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;
- size = round_up(size, PAGE_SIZE);
-
cma_obj = kzalloc(sizeof(*cma_obj), GFP_KERNEL);
if (!cma_obj)
return ERR_PTR(-ENOMEM);
- cma_obj->vaddr = dma_alloc_writecombine(drm->dev, size,
- &cma_obj->paddr, GFP_KERNEL | __GFP_NOWARN);
- if (!cma_obj->vaddr) {
- dev_err(drm->dev, "failed to allocate buffer with size %d\n", size);
- ret = -ENOMEM;
- goto err_dma_alloc;
- }
-
gem_obj = &cma_obj->base;
ret = drm_gem_object_init(drm, gem_obj, size);
if (ret)
- goto err_obj_init;
+ goto error;
ret = drm_gem_create_mmap_offset(gem_obj);
- if (ret)
- goto err_create_mmap_offset;
+ if (ret) {
+ drm_gem_object_release(gem_obj);
+ goto error;
+ }
return cma_obj;
-err_create_mmap_offset:
- drm_gem_object_release(gem_obj);
+error:
+ kfree(cma_obj);
+ return ERR_PTR(ret);
+}
-err_obj_init:
- drm_gem_cma_buf_destroy(drm, cma_obj);
+/**
+ * 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;
-err_dma_alloc:
- kfree(cma_obj);
+ size = round_up(size, PAGE_SIZE);
+
+ cma_obj = __drm_gem_cma_create(drm, size);
+ if (IS_ERR(cma_obj))
+ return cma_obj;
+ cma_obj->vaddr = dma_alloc_writecombine(drm->dev, size,
+ &cma_obj->paddr, GFP_KERNEL | __GFP_NOWARN);
+ if (!cma_obj->vaddr) {
+ dev_err(drm->dev, "failed to allocate buffer with size %zu\n",
+ size);
+ ret = -ENOMEM;
+ goto error;
+ }
+
+ return cma_obj;
+
+error:
+ drm_gem_cma_free_object(&cma_obj->base);
return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(drm_gem_cma_create);
-/*
- * drm_gem_cma_create_with_handle - allocate an object with the given
- * size and create a gem handle on it
+/**
+ * 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 ERR_PTR values
- * on failure.
+ * 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, unsigned int size,
- unsigned int *handle)
+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;
return ERR_PTR(ret);
}
-/*
- * drm_gem_cma_free_object - (struct drm_driver)->gem_free_object callback
- * function
+/**
+ * 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.
+ * Drivers using the CMA helpers should set this as their DRM driver's
+ * ->gem_free_object() callback.
*/
void drm_gem_cma_free_object(struct drm_gem_object *gem_obj)
{
struct drm_gem_cma_object *cma_obj;
- if (gem_obj->map_list.map)
- drm_gem_free_mmap_offset(gem_obj);
-
- drm_gem_object_release(gem_obj);
-
cma_obj = to_drm_gem_cma_obj(gem_obj);
- drm_gem_cma_buf_destroy(gem_obj->dev, cma_obj);
+ if (cma_obj->vaddr) {
+ dma_free_writecombine(gem_obj->dev->dev, cma_obj->base.size,
+ cma_obj->vaddr, cma_obj->paddr);
+ } else if (gem_obj->import_attach) {
+ drm_prime_gem_destroy(gem_obj, cma_obj->sgt);
+ }
+
+ drm_gem_object_release(gem_obj);
kfree(cma_obj);
}
EXPORT_SYMBOL_GPL(drm_gem_cma_free_object);
-/*
- * drm_gem_cma_dumb_create - (struct drm_driver)->dumb_create callback
- * function
+/**
+ * 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. wrap
- * this into your own function if you need bigger alignment.
+ * 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 the ->dumb_create() callback in a DRM driver.
+ *
+ * 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 *dev, struct drm_mode_create_dumb *args)
+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;
- int min_pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
if (args->pitch < min_pitch)
args->pitch = min_pitch;
if (args->size < args->pitch * args->height)
args->size = args->pitch * args->height;
- cma_obj = drm_gem_cma_create_with_handle(file_priv, dev,
- args->size, &args->handle);
- if (IS_ERR(cma_obj))
- return PTR_ERR(cma_obj);
+ 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);
- return 0;
+/**
+ * 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 ->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);
-/*
- * drm_gem_cma_dumb_map_offset - (struct drm_driver)->dumb_map_offset callback
- * function
+/**
+ * drm_gem_cma_dumb_map_offset - return the fake mmap offset for a CMA GEM
+ * object
+ * @file_priv: DRM file-private structure containing the GEM object
+ * @drm: DRM device
+ * @handle: GEM object handle
+ * @offset: return location for the fake mmap offset
+ *
+ * This function look up an object by its handle and returns the fake mmap
+ * offset associated with it. Drivers using the CMA helpers should set this
+ * as their DRM driver's ->dumb_map_offset() callback.
+ *
+ * Returns:
+ * 0 on success or a negative error code on failure.
*/
int drm_gem_cma_dumb_map_offset(struct drm_file *file_priv,
- struct drm_device *drm, uint32_t handle, uint64_t *offset)
+ struct drm_device *drm, u32 handle,
+ u64 *offset)
{
struct drm_gem_object *gem_obj;
- mutex_lock(&drm->struct_mutex);
-
gem_obj = drm_gem_object_lookup(drm, file_priv, handle);
if (!gem_obj) {
- dev_err(drm->dev, "failed to lookup gem object\n");
- mutex_unlock(&drm->struct_mutex);
+ dev_err(drm->dev, "failed to lookup GEM object\n");
return -EINVAL;
}
- *offset = get_gem_mmap_offset(gem_obj);
-
- drm_gem_object_unreference(gem_obj);
+ *offset = drm_vma_node_offset_addr(&gem_obj->vma_node);
- mutex_unlock(&drm->struct_mutex);
+ drm_gem_object_unreference_unlocked(gem_obj);
return 0;
}
};
EXPORT_SYMBOL_GPL(drm_gem_cma_vm_ops);
-/*
- * drm_gem_cma_mmap - (struct file_operation)->mmap callback function
+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_writecombine(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.
+ *
+ * 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_object *gem_obj;
struct drm_gem_cma_object *cma_obj;
+ struct drm_gem_object *gem_obj;
int ret;
ret = drm_gem_mmap(filp, vma);
gem_obj = vma->vm_private_data;
cma_obj = to_drm_gem_cma_obj(gem_obj);
- ret = remap_pfn_range(vma, vma->vm_start, cma_obj->paddr >> PAGE_SHIFT,
- vma->vm_end - vma->vm_start, vma->vm_page_prot);
- if (ret)
- drm_gem_vm_close(vma);
-
- return ret;
+ return drm_gem_cma_mmap_obj(cma_obj, vma);
}
EXPORT_SYMBOL_GPL(drm_gem_cma_mmap);
-/*
- * drm_gem_cma_dumb_destroy - (struct drm_driver)->dumb_destroy callback function
- */
-int drm_gem_cma_dumb_destroy(struct drm_file *file_priv,
- struct drm_device *drm, unsigned int handle)
-{
- return drm_gem_handle_delete(file_priv, handle);
-}
-EXPORT_SYMBOL_GPL(drm_gem_cma_dumb_destroy);
-
#ifdef CONFIG_DEBUG_FS
-void drm_gem_cma_describe(struct drm_gem_cma_object *cma_obj, struct seq_file *m)
+/**
+ * drm_gem_cma_describe - describe a CMA GEM object for debugfs
+ * @cma_obj: CMA GEM object
+ * @m: debugfs file handle
+ *
+ * This function can be used to dump a human-readable representation of the
+ * CMA GEM object into a synthetic file.
+ */
+void drm_gem_cma_describe(struct drm_gem_cma_object *cma_obj,
+ struct seq_file *m)
{
struct drm_gem_object *obj = &cma_obj->base;
- struct drm_device *dev = obj->dev;
- uint64_t off = 0;
+ uint64_t off;
- WARN_ON(!mutex_is_locked(&dev->struct_mutex));
+ off = drm_vma_node_start(&obj->vma_node);
- if (obj->map_list.map)
- off = (uint64_t)obj->map_list.hash.key;
-
- seq_printf(m, "%2d (%2d) %08llx %08Zx %p %d",
+ seq_printf(m, "%2d (%2d) %08llx %pad %p %zu",
obj->name, obj->refcount.refcount.counter,
- off, cma_obj->paddr, cma_obj->vaddr, obj->size);
+ off, &cma_obj->paddr, cma_obj->vaddr, obj->size);
seq_printf(m, "\n");
}
EXPORT_SYMBOL_GPL(drm_gem_cma_describe);
#endif
+
+/**
+ * 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's ->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 NULL;
+
+ 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 NULL;
+}
+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's
+ * ->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;
+
+ if (sgt->nents != 1)
+ 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's ->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 ->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's ->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);
projects / firefly-linux-kernel-4.4.55.git / blobdiff