From 05fc03217e08b90bff1ff22792d5f86dd32f15a6 Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Thu, 29 Dec 2016 21:48:23 +0100 Subject: drm/mm: Some doc polish Added some boilerplate for the structs, documented members where they are relevant and plenty of markup for hyperlinks all over. And a few small wording polish. Note that the intro needs some more love after the DRM_MM_INSERT_* patch from Chris has landed. v2: Spelling fixes (Chris). v3: Use &struct foo instead of &foo structure (Chris). Cc: Chris Wilson Cc: Joonas Lahtinen Reviewed-by: David Herrmann Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/1483044517-5770-3-git-send-email-daniel.vetter@ffwll.ch --- include/drm/drm_mm.h | 84 +++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 66 insertions(+), 18 deletions(-) (limited to 'include/drm') diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h index 1383ac2328b8..3bddca8fd2b5 100644 --- a/include/drm/drm_mm.h +++ b/include/drm/drm_mm.h @@ -67,16 +67,29 @@ enum drm_mm_allocator_flags { #define DRM_MM_BOTTOMUP DRM_MM_SEARCH_DEFAULT, DRM_MM_CREATE_DEFAULT #define DRM_MM_TOPDOWN DRM_MM_SEARCH_BELOW, DRM_MM_CREATE_TOP +/** + * struct drm_mm_node - allocated block in the DRM allocator + * + * This represents an allocated block in a &drm_mm allocator. Except for + * pre-reserved nodes inserted using drm_mm_reserve_node() the structure is + * entirely opaque and should only be accessed through the provided funcions. + * Since allocation of these nodes is entirely handled by the driver they can be + * embedded. + */ struct drm_mm_node { + /** @color: Opaque driver-private tag. */ + unsigned long color; + /** @start: Start address of the allocated block. */ + u64 start; + /** @size: Size of the allocated block. */ + u64 size; + /* private: */ struct list_head node_list; struct list_head hole_stack; struct rb_node rb; unsigned hole_follows : 1; unsigned allocated : 1; bool scanned_block : 1; - unsigned long color; - u64 start; - u64 size; u64 __subtree_last; struct drm_mm *mm; #ifdef CONFIG_DRM_DEBUG_MM @@ -84,7 +97,29 @@ struct drm_mm_node { #endif }; +/** + * struct drm_mm - DRM allocator + * + * DRM range allocator with a few special functions and features geared towards + * managing GPU memory. Except for the @color_adjust callback the structure is + * entirely opaque and should only be accessed through the provided functions + * and macros. This structure can be embedded into larger driver structures. + */ struct drm_mm { + /** + * @color_adjust: + * + * Optional driver callback to further apply restrictions on a hole. The + * node argument points at the node containing the hole from which the + * block would be allocated (see drm_mm_hole_follows() and friends). The + * other arguments are the size of the block to be allocated. The driver + * can adjust the start and end as needed to e.g. insert guard pages. + */ + void (*color_adjust)(const struct drm_mm_node *node, + unsigned long color, + u64 *start, u64 *end); + + /* private: */ /* List of all memory nodes that immediately precede a free hole. */ struct list_head hole_stack; /* head_node.node_list is the list of all memory nodes, ordered @@ -93,14 +128,20 @@ struct drm_mm { /* Keep an interval_tree for fast lookup of drm_mm_nodes by address. */ struct rb_root interval_tree; - void (*color_adjust)(const struct drm_mm_node *node, - unsigned long color, - u64 *start, u64 *end); - unsigned long scan_active; }; +/** + * struct drm_mm_scan - DRM allocator eviction roaster data + * + * This structure tracks data needed for the eviction roaster set up using + * drm_mm_scan_init(), and used with drm_mm_scan_add_block() and + * drm_mm_scan_remove_block(). The structure is entirely opaque and should only + * be accessed through the provided functions and macros. It is meant to be + * allocated temporarily by the driver on the stack. + */ struct drm_mm_scan { + /* private: */ struct drm_mm *mm; u64 size; @@ -159,7 +200,8 @@ static inline bool drm_mm_initialized(const struct drm_mm *mm) * * Holes are embedded into the drm_mm using the tail of a drm_mm_node. * If you wish to know whether a hole follows this particular node, - * query this function. + * query this function. See also drm_mm_hole_node_start() and + * drm_mm_hole_node_end(). * * Returns: * True if a hole follows the @node. @@ -228,23 +270,23 @@ static inline u64 drm_mm_hole_node_end(const struct drm_mm_node *hole_node) /** * drm_mm_for_each_node - iterator to walk over all allocated nodes - * @entry: drm_mm_node structure to assign to in each iteration step - * @mm: drm_mm allocator to walk + * @entry: &struct drm_mm_node to assign to in each iteration step + * @mm: &drm_mm allocator to walk * * This iterator walks over all nodes in the range allocator. It is implemented - * with list_for_each, so not save against removal of elements. + * with list_for_each(), so not save against removal of elements. */ #define drm_mm_for_each_node(entry, mm) \ list_for_each_entry(entry, drm_mm_nodes(mm), node_list) /** * drm_mm_for_each_node_safe - iterator to walk over all allocated nodes - * @entry: drm_mm_node structure to assign to in each iteration step - * @next: drm_mm_node structure to store the next step - * @mm: drm_mm allocator to walk + * @entry: &struct drm_mm_node to assign to in each iteration step + * @next: &struct drm_mm_node to store the next step + * @mm: &drm_mm allocator to walk * * This iterator walks over all nodes in the range allocator. It is implemented - * with list_for_each_safe, so save against removal of elements. + * with list_for_each_safe(), so save against removal of elements. */ #define drm_mm_for_each_node_safe(entry, next, mm) \ list_for_each_entry_safe(entry, next, drm_mm_nodes(mm), node_list) @@ -259,13 +301,13 @@ static inline u64 drm_mm_hole_node_end(const struct drm_mm_node *hole_node) /** * drm_mm_for_each_hole - iterator to walk over all holes - * @entry: drm_mm_node used internally to track progress - * @mm: drm_mm allocator to walk + * @entry: &drm_mm_node used internally to track progress + * @mm: &drm_mm allocator to walk * @hole_start: ulong variable to assign the hole start to on each iteration * @hole_end: ulong variable to assign the hole end to on each iteration * * This iterator walks over all holes in the range allocator. It is implemented - * with list_for_each, so not save against removal of elements. @entry is used + * with list_for_each(), so not save against removal of elements. @entry is used * internally and will not reflect a real drm_mm_node for the very first hole. * Hence users of this iterator may not access it. * @@ -334,6 +376,9 @@ static inline int drm_mm_insert_node_in_range(struct drm_mm *mm, * @sflags: flags to fine-tune the allocation search * @aflags: flags to fine-tune the allocation behavior * + * This is a simplified version of drm_mm_insert_node_in_range_generic() with no + * range restrictions applied. + * * The preallocated node must be cleared to 0. * * Returns: @@ -434,6 +479,9 @@ void drm_mm_scan_init_with_range(struct drm_mm_scan *scan, * @color: opaque tag value to use for the allocation * @flags: flags to specify how the allocation will be performed afterwards * + * This is a simplified version of drm_mm_scan_init_with_range() with no range + * restrictions applied. + * * This simply sets up the scanning routines with the parameters for the desired * hole. * -- cgit v1.2.3