While at it do a tiny bit of interface cleanup and convert boolean return values to bool. With this patch all exported functions and inline helpers which are part of the drm_mm public interface are documented.
Also drop superflous extern function modifiers since most of drm_mm.h doesn't use them - more consistent that way.
Signed-off-by: Daniel Vetter daniel.vetter@ffwll.ch --- Documentation/DocBook/drm.tmpl | 5 ++ drivers/gpu/drm/drm_mm.c | 144 ++++++++++++++++++++++++++++++++------ include/drm/drm_mm.h | 154 +++++++++++++++++++++++++++++++++-------- 3 files changed, 251 insertions(+), 52 deletions(-)
diff --git a/Documentation/DocBook/drm.tmpl b/Documentation/DocBook/drm.tmpl index 2ac018bfbddf..d68bb0a2dc06 100644 --- a/Documentation/DocBook/drm.tmpl +++ b/Documentation/DocBook/drm.tmpl @@ -931,6 +931,11 @@ struct drm_gem_object * (*gem_prime_import)(struct drm_device *dev, !Pdrivers/gpu/drm/drm_mm.c lru scan roaster </sect3> </sect2> + <sect2> + <title>DRM MM Range Allocator Function References</title> +!Edrivers/gpu/drm/drm_mm.c +!Iinclude/drm/drm_mm.h + </sect2> </sect1>
<!-- Internals: mode setting --> diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c index 276a7a27c166..a2d45b748f86 100644 --- a/drivers/gpu/drm/drm_mm.c +++ b/drivers/gpu/drm/drm_mm.c @@ -144,6 +144,20 @@ static void drm_mm_insert_helper(struct drm_mm_node *hole_node, } }
+/** + * drm_mm_reserve_node - insert an pre-initialized node + * @mm: drm_mm allocator to insert @node into + * @node: drm_mm_node to insert + * + * This functions inserts an already set-up drm_mm_node into the allocator, + * meaning that start, size and color must be set by the caller. This is useful + * to initialize the allocator with preallocated objects which must be set-up + * before the range allocator can be set-up, e.g. when taking over a firmware + * framebuffer. + * + * Returns: + * 0 on success, -ENOSPC if there's no hole where @node is. + */ int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node) { struct drm_mm_node *hole; @@ -185,9 +199,18 @@ int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node) EXPORT_SYMBOL(drm_mm_reserve_node);
/** - * Search for free space and insert a preallocated memory node. Returns - * -ENOSPC if no suitable free area is available. The preallocated memory node - * must be cleared. + * drm_mm_insert_node_generic - search for space and insert @node + * @mm: drm_mm to allocate from + * @node: preallocate node to insert + * @size: size of the allocation + * @alignment: alignment of the allocation + * @color: opaque tag value to use for this node + * @flags: flags to fine-tune the allocation + * + * The preallocated node must be cleared to 0. + * + * Returns: + * 0 on success, -ENOSPC if there's no suitable hole. */ int drm_mm_insert_node_generic(struct drm_mm *mm, struct drm_mm_node *node, unsigned long size, unsigned alignment, @@ -259,9 +282,20 @@ static void drm_mm_insert_helper_range(struct drm_mm_node *hole_node, }
/** - * Search for free space and insert a preallocated memory node. Returns - * -ENOSPC if no suitable free area is available. This is for range - * restricted allocations. The preallocated memory node must be cleared. + * drm_mm_insert_node_in_range_generic - ranged search for space and insert @node + * @mm: drm_mm to allocate from + * @node: preallocate node to insert + * @size: size of the allocation + * @alignment: alignment of the allocation + * @color: opaque tag value to use for this node + * @start: start of the allowed range for this node + * @end: end of the allowed range for this node + * @flags: flags to fine-tune the allocation + * + * The preallocated node must be cleared to 0. + * + * Returns: + * 0 on success, -ENOSPC if there's no suitable hole. */ int drm_mm_insert_node_in_range_generic(struct drm_mm *mm, struct drm_mm_node *node, unsigned long size, unsigned alignment, unsigned long color, @@ -284,7 +318,12 @@ int drm_mm_insert_node_in_range_generic(struct drm_mm *mm, struct drm_mm_node *n EXPORT_SYMBOL(drm_mm_insert_node_in_range_generic);
/** - * Remove a memory node from the allocator. + * drm_mm_remove_node - Remove a memory node from the allocator. + * @node: drm_mm_node to remove + * + * This just removes a node from its drm_mm allocator. The node does not need to + * be cleared again before it can be re-inserted into this or any other drm_mm + * allocator. It is a bug to call this function on a un-allocated node. */ void drm_mm_remove_node(struct drm_mm_node *node) { @@ -421,7 +460,13 @@ static struct drm_mm_node *drm_mm_search_free_in_range_generic(const struct drm_ }
/** - * Moves an allocation. To be used with embedded struct drm_mm_node. + * drm_mm_replace_node - move an allocation from @old to @new + * @old: drm_mm_node to remove from the allocator + * @new: drm_mm_node which should inherit @old's allocation + * + * This is useful for when drivers embed the drm_mm_node structure and hence + * can't move allocations by reassigning pointers. It's a combination of remove + * and insert with the guarantee that the allocation start will match. */ void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new) { @@ -467,12 +512,18 @@ EXPORT_SYMBOL(drm_mm_replace_node); */
/** - * Initializa lru scanning. + * drm_mm_init_scan - initialize lru scanning + * @mm: drm_mm to scan + * @size: size of the allocation + * @alignment: alignment of the allocation + * @color: opaque tag value to use for the allocation * * This simply sets up the scanning routines with the parameters for the desired - * hole. + * hole. Note that there's no need to specify allocation flags, since they only + * change the place a node is allocated from within a suitable hole. * - * Warning: As long as the scan list is non-empty, no other operations than + * Warning: + * As long as the scan list is non-empty, no other operations than * adding/removing nodes to/from the scan list are allowed. */ void drm_mm_init_scan(struct drm_mm *mm, @@ -492,12 +543,20 @@ void drm_mm_init_scan(struct drm_mm *mm, EXPORT_SYMBOL(drm_mm_init_scan);
/** - * Initializa lru scanning. + * drm_mm_init_scan - initialize range-restricted lru scanning + * @mm: drm_mm to scan + * @size: size of the allocation + * @alignment: alignment of the allocation + * @color: opaque tag value to use for the allocation + * @start: start of the allowed range for the allocation + * @end: end of the allowed range for the allocation * * This simply sets up the scanning routines with the parameters for the desired - * hole. This version is for range-restricted scans. + * hole. Note that there's no need to specify allocation flags, since they only + * change the place a node is allocated from within a suitable hole. * - * Warning: As long as the scan list is non-empty, no other operations than + * Warning: + * As long as the scan list is non-empty, no other operations than * adding/removing nodes to/from the scan list are allowed. */ void drm_mm_init_scan_with_range(struct drm_mm *mm, @@ -521,12 +580,16 @@ void drm_mm_init_scan_with_range(struct drm_mm *mm, EXPORT_SYMBOL(drm_mm_init_scan_with_range);
/** + * drm_mm_scan_add_block - add a node to the scan list + * @node: drm_mm_node to add + * * Add a node to the scan list that might be freed to make space for the desired * hole. * - * Returns non-zero, if a hole has been found, zero otherwise. + * Returns: + * True if a hole has been found, false otherwise. */ -int drm_mm_scan_add_block(struct drm_mm_node *node) +bool drm_mm_scan_add_block(struct drm_mm_node *node) { struct drm_mm *mm = node->mm; struct drm_mm_node *prev_node; @@ -566,15 +629,16 @@ int drm_mm_scan_add_block(struct drm_mm_node *node) mm->scan_size, mm->scan_alignment)) { mm->scan_hit_start = hole_start; mm->scan_hit_end = hole_end; - return 1; + return true; }
- return 0; + return false; } EXPORT_SYMBOL(drm_mm_scan_add_block);
/** - * Remove a node from the scan list. + * drm_mm_scan_remove_block - remove a node from the scan list + * @node: drm_mm_node to remove * * Nodes _must_ be removed in the exact same order from the scan list as they * have been added, otherwise the internal state of the memory manager will be @@ -584,10 +648,11 @@ EXPORT_SYMBOL(drm_mm_scan_add_block); * immediately following drm_mm_search_free with !DRM_MM_SEARCH_BEST will then * return the just freed block (because its at the top of the free_stack list). * - * Returns one if this block should be evicted, zero otherwise. Will always - * return zero when no hole has been found. + * Returns: + * True if this block should be evicted, false otherwise. Will always + * return false when no hole has been found. */ -int drm_mm_scan_remove_block(struct drm_mm_node *node) +bool drm_mm_scan_remove_block(struct drm_mm_node *node) { struct drm_mm *mm = node->mm; struct drm_mm_node *prev_node; @@ -608,7 +673,15 @@ int drm_mm_scan_remove_block(struct drm_mm_node *node) } EXPORT_SYMBOL(drm_mm_scan_remove_block);
-int drm_mm_clean(struct drm_mm * mm) +/** + * drm_mm_clean - checks whether an allocator is clean + * @mm: drm_mm allocator to check + * + * Returns: + * True if the allocator is completely free, false if there's still a node + * allocated in it. + */ +bool drm_mm_clean(struct drm_mm * mm) { struct list_head *head = &mm->head_node.node_list;
@@ -616,6 +689,14 @@ int drm_mm_clean(struct drm_mm * mm) } EXPORT_SYMBOL(drm_mm_clean);
+/** + * drm_mm_init - initialize a drm-mm allocator + * @mm: the drm_mm structure to initialize + * @start: start of the range managed by @mm + * @size: end of the range managed by @mm + * + * Note that @mm must be cleared to 0 before calling this function. + */ void drm_mm_init(struct drm_mm * mm, unsigned long start, unsigned long size) { INIT_LIST_HEAD(&mm->hole_stack); @@ -637,6 +718,13 @@ void drm_mm_init(struct drm_mm * mm, unsigned long start, unsigned long size) } EXPORT_SYMBOL(drm_mm_init);
+/** + * drm_mm_takedown - clean up a drm_mm allocator + * @mm: drm_mm allocator to clean up + * + * Note that it is a bug to call this function on an allocator which is not + * clean. + */ void drm_mm_takedown(struct drm_mm * mm) { WARN(!list_empty(&mm->head_node.node_list), @@ -662,6 +750,11 @@ static unsigned long drm_mm_debug_hole(struct drm_mm_node *entry, return 0; }
+/** + * drm_mm_debug_table - dump allocator state to dmesg + * @mm: drm_mm allocator to dump + * @prefix: prefix to use for dumping to dmesg + */ void drm_mm_debug_table(struct drm_mm *mm, const char *prefix) { struct drm_mm_node *entry; @@ -700,6 +793,11 @@ static unsigned long drm_mm_dump_hole(struct seq_file *m, struct drm_mm_node *en return 0; }
+/** + * drm_mm_dump_table - dump allocator state to a seq_file + * @m: seq_file to dump to + * @mm: drm_mm allocator to dump + */ int drm_mm_dump_table(struct seq_file *m, struct drm_mm *mm) { struct drm_mm_node *entry; diff --git a/include/drm/drm_mm.h b/include/drm/drm_mm.h index cba67865d18f..8b6981ab3fcf 100644 --- a/include/drm/drm_mm.h +++ b/include/drm/drm_mm.h @@ -85,11 +85,31 @@ struct drm_mm { unsigned long *start, unsigned long *end); };
+/** + * drm_mm_node_allocated - checks whether a node is allocated + * @node: drm_mm_node to check + * + * Drivers should use this helpers for proper encapusulation of drm_mm + * internals. + * + * Returns: + * True if the @node is allocated. + */ static inline bool drm_mm_node_allocated(struct drm_mm_node *node) { return node->allocated; }
+/** + * drm_mm_initialized - checks whether an allocator is initialized + * @mm: drm_mm to check + * + * Drivers should use this helpers for proper encapusulation of drm_mm + * internals. + * + * Returns: + * True if the @mm is initialized. + */ static inline bool drm_mm_initialized(struct drm_mm *mm) { return mm->hole_stack.next; @@ -100,6 +120,17 @@ static inline unsigned long __drm_mm_hole_node_start(struct drm_mm_node *hole_no return hole_node->start + hole_node->size; }
+/** + * drm_mm_hole_node_start - computes the start of the hole following @node + * @hole_node: drm_mm_node which implicitly tracks the following hole + * + * This is useful for driver-sepific debug dumpers. Otherwise drivers should not + * inspect holes themselves. Drivers must check first whether a hole indeed + * follows by looking at node->hole_follows. + * + * Returns: + * Start of the subsequent hole. + */ static inline unsigned long drm_mm_hole_node_start(struct drm_mm_node *hole_node) { BUG_ON(!hole_node->hole_follows); @@ -112,18 +143,49 @@ static inline unsigned long __drm_mm_hole_node_end(struct drm_mm_node *hole_node struct drm_mm_node, node_list)->start; }
+/** + * drm_mm_hole_node_end - computes the end of the hole following @node + * @hole_node: drm_mm_node which implicitly tracks the following hole + * + * This is useful for driver-sepific debug dumpers. Otherwise drivers should not + * inspect holes themselves. Drivers must check first whether a hole indeed + * follows by looking at node->hole_follows. + * + * Returns: + * End of the subsequent hole. + */ static inline unsigned long drm_mm_hole_node_end(struct drm_mm_node *hole_node) { return __drm_mm_hole_node_end(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 + * + * This iterator walks over all nodes in the range allocator. It is implemented + * with list_for_each, so not save against removal of elements. + */ #define drm_mm_for_each_node(entry, mm) list_for_each_entry(entry, \ &(mm)->head_node.node_list, \ node_list)
-/* Note that we need to unroll list_for_each_entry in order to inline - * setting hole_start and hole_end on each iteration and keep the - * macro sane. +/** + * 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 + * @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 + * internally and will not reflect a real drm_mm_node for the very first hole. + * Hence users of this iterator may not access it. + * + * Implementation Note: + * We need to inline list_for_each_entry in order to be able to set hole_start + * and hole_end on each iteration while keeping the macro sane. */ #define drm_mm_for_each_hole(entry, mm, hole_start, hole_end) \ for (entry = list_entry((mm)->hole_stack.next, struct drm_mm_node, hole_stack); \ @@ -136,14 +198,30 @@ static inline unsigned long drm_mm_hole_node_end(struct drm_mm_node *hole_node) /* * Basic range manager support (drm_mm.c) */ -extern int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node); - -extern int drm_mm_insert_node_generic(struct drm_mm *mm, - struct drm_mm_node *node, - unsigned long size, - unsigned alignment, - unsigned long color, - enum drm_mm_search_flags flags); +int drm_mm_reserve_node(struct drm_mm *mm, struct drm_mm_node *node); + +int drm_mm_insert_node_generic(struct drm_mm *mm, + struct drm_mm_node *node, + unsigned long size, + unsigned alignment, + unsigned long color, + enum drm_mm_search_flags flags); +/** + * drm_mm_insert_node - search for space and insert @node + * @mm: drm_mm to allocate from + * @node: preallocate node to insert + * @size: size of the allocation + * @alignment: alignment of the allocation + * @flags: flags to fine-tune the allocation + * + * This is a simplified version of drm_mm_insert_node_generic() with @color set + * to 0. + * + * The preallocated node must be cleared to 0. + * + * Returns: + * 0 on success, -ENOSPC if there's no suitable hole. + */ static inline int drm_mm_insert_node(struct drm_mm *mm, struct drm_mm_node *node, unsigned long size, @@ -153,14 +231,32 @@ static inline int drm_mm_insert_node(struct drm_mm *mm, return drm_mm_insert_node_generic(mm, node, size, alignment, 0, flags); }
-extern int drm_mm_insert_node_in_range_generic(struct drm_mm *mm, - struct drm_mm_node *node, - unsigned long size, - unsigned alignment, - unsigned long color, - unsigned long start, - unsigned long end, - enum drm_mm_search_flags flags); +int drm_mm_insert_node_in_range_generic(struct drm_mm *mm, + struct drm_mm_node *node, + unsigned long size, + unsigned alignment, + unsigned long color, + unsigned long start, + unsigned long end, + enum drm_mm_search_flags flags); +/** + * drm_mm_insert_node_in_range - ranged search for space and insert @node + * @mm: drm_mm to allocate from + * @node: preallocate node to insert + * @size: size of the allocation + * @alignment: alignment of the allocation + * @start: start of the allowed range for this node + * @end: end of the allowed range for this node + * @flags: flags to fine-tune the allocation + * + * This is a simplified version of drm_mm_insert_node_in_range_generic() with + * @color set to 0. + * + * The preallocated node must be cleared to 0. + * + * Returns: + * 0 on success, -ENOSPC if there's no suitable hole. + */ static inline int drm_mm_insert_node_in_range(struct drm_mm *mm, struct drm_mm_node *node, unsigned long size, @@ -173,13 +269,13 @@ static inline int drm_mm_insert_node_in_range(struct drm_mm *mm, 0, start, end, flags); }
-extern void drm_mm_remove_node(struct drm_mm_node *node); -extern void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new); -extern void drm_mm_init(struct drm_mm *mm, - unsigned long start, - unsigned long size); -extern void drm_mm_takedown(struct drm_mm *mm); -extern int drm_mm_clean(struct drm_mm *mm); +void drm_mm_remove_node(struct drm_mm_node *node); +void drm_mm_replace_node(struct drm_mm_node *old, struct drm_mm_node *new); +void drm_mm_init(struct drm_mm *mm, + unsigned long start, + unsigned long size); +void drm_mm_takedown(struct drm_mm *mm); +bool drm_mm_clean(struct drm_mm *mm);
void drm_mm_init_scan(struct drm_mm *mm, unsigned long size, @@ -191,10 +287,10 @@ void drm_mm_init_scan_with_range(struct drm_mm *mm, unsigned long color, unsigned long start, unsigned long end); -int drm_mm_scan_add_block(struct drm_mm_node *node); -int drm_mm_scan_remove_block(struct drm_mm_node *node); +bool drm_mm_scan_add_block(struct drm_mm_node *node); +bool drm_mm_scan_remove_block(struct drm_mm_node *node);
-extern void drm_mm_debug_table(struct drm_mm *mm, const char *prefix); +void drm_mm_debug_table(struct drm_mm *mm, const char *prefix); #ifdef CONFIG_DEBUG_FS int drm_mm_dump_table(struct seq_file *m, struct drm_mm *mm); #endif