--- zzzz-none-000/linux-3.10.107/drivers/gpu/drm/drm_gem_cma_helper.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/drivers/gpu/drm/drm_gem_cma_helper.c 2021-02-04 17:41:59.000000000 +0000 @@ -21,87 +21,129 @@ #include #include #include +#include #include #include #include #include +#include -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 + * + * 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 ERR_PTR values - * on failure. + * 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 - * - * returns a struct drm_gem_cma_object* on success or ERR_PTR values - * on failure. - */ -static struct drm_gem_cma_object *drm_gem_cma_create_with_handle( - struct drm_file *file_priv, - struct drm_device *drm, unsigned int size, - unsigned int *handle) +/** + * 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; @@ -132,39 +174,54 @@ 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. 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. * - * This aligns the pitch and size arguments to the minimum required. wrap - * this into your own function if you need bigger alignment. + * 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; @@ -172,38 +229,75 @@ 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); + *offset = drm_vma_node_offset_addr(&gem_obj->vma_node); - drm_gem_object_unreference(gem_obj); - - mutex_unlock(&drm->struct_mutex); + drm_gem_object_unreference_unlocked(gem_obj); return 0; } @@ -215,13 +309,47 @@ }; 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); @@ -231,42 +359,174 @@ 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);