From 950fd867c6354c15fd5c36da4a0c72daa3036576 Mon Sep 17 00:00:00 2001 From: Eric Anholt Date: Fri, 11 May 2018 09:35:15 -0700 Subject: [PATCH] staging: bcm2835-camera: Replace open-coded idr with a struct idr. We just need some integer handles that can map back to our message struct when we're handling a reply, which struct idr is perfect for. v2: Fix error check to look at the right variable. Signed-off-by: Eric Anholt Signed-off-by: Greg Kroah-Hartman --- .../vc04_services/bcm2835-camera/mmal-vchiq.c | 135 ++++-------------- 1 file changed, 31 insertions(+), 104 deletions(-) diff --git a/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c b/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c index 3a3b843fc122..f5b5ead6347c 100644 --- a/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c +++ b/drivers/staging/vc04_services/bcm2835-camera/mmal-vchiq.c @@ -21,7 +21,6 @@ #include #include #include -#include #include #include @@ -111,7 +110,11 @@ struct vchiq_mmal_instance; /* normal message context */ struct mmal_msg_context { struct vchiq_mmal_instance *instance; - u32 handle; + + /* Index in the context_map idr so that we can find the + * mmal_msg_context again when servicing the VCHI reply. + */ + int handle; union { struct { @@ -149,13 +152,6 @@ struct mmal_msg_context { }; -struct vchiq_mmal_context_map { - /* ensure serialized access to the btree(contention should be low) */ - struct mutex lock; - struct btree_head32 btree_head; - u32 last_handle; -}; - struct vchiq_mmal_instance { VCHI_SERVICE_HANDLE_T handle; @@ -165,92 +161,19 @@ struct vchiq_mmal_instance { /* vmalloc page to receive scratch bulk xfers into */ void *bulk_scratch; - /* mapping table between context handles and mmal_msg_contexts */ - struct vchiq_mmal_context_map context_map; + struct idr context_map; + spinlock_t context_map_lock; /* component to use next */ int component_idx; struct vchiq_mmal_component component[VCHIQ_MMAL_MAX_COMPONENTS]; }; -static int __must_check -mmal_context_map_init(struct vchiq_mmal_context_map *context_map) -{ - mutex_init(&context_map->lock); - context_map->last_handle = 0; - return btree_init32(&context_map->btree_head); -} - -static void mmal_context_map_destroy(struct vchiq_mmal_context_map *context_map) -{ - mutex_lock(&context_map->lock); - btree_destroy32(&context_map->btree_head); - mutex_unlock(&context_map->lock); -} - -static u32 -mmal_context_map_create_handle(struct vchiq_mmal_context_map *context_map, - struct mmal_msg_context *msg_context, - gfp_t gfp) -{ - u32 handle; - - mutex_lock(&context_map->lock); - - while (1) { - /* just use a simple count for handles, but do not use 0 */ - context_map->last_handle++; - if (!context_map->last_handle) - context_map->last_handle++; - - handle = context_map->last_handle; - - /* check if the handle is already in use */ - if (!btree_lookup32(&context_map->btree_head, handle)) - break; - } - - if (btree_insert32(&context_map->btree_head, handle, - msg_context, gfp)) { - /* probably out of memory */ - mutex_unlock(&context_map->lock); - return 0; - } - - mutex_unlock(&context_map->lock); - return handle; -} - -static struct mmal_msg_context * -mmal_context_map_lookup_handle(struct vchiq_mmal_context_map *context_map, - u32 handle) -{ - struct mmal_msg_context *msg_context; - - if (!handle) - return NULL; - - mutex_lock(&context_map->lock); - - msg_context = btree_lookup32(&context_map->btree_head, handle); - - mutex_unlock(&context_map->lock); - return msg_context; -} - -static void -mmal_context_map_destroy_handle(struct vchiq_mmal_context_map *context_map, - u32 handle) -{ - mutex_lock(&context_map->lock); - btree_remove32(&context_map->btree_head, handle); - mutex_unlock(&context_map->lock); -} - static struct mmal_msg_context * get_msg_context(struct vchiq_mmal_instance *instance) { struct mmal_msg_context *msg_context; + int handle; /* todo: should this be allocated from a pool to avoid kzalloc */ msg_context = kzalloc(sizeof(*msg_context), GFP_KERNEL); @@ -258,32 +181,40 @@ get_msg_context(struct vchiq_mmal_instance *instance) if (!msg_context) return ERR_PTR(-ENOMEM); - msg_context->instance = instance; - msg_context->handle = - mmal_context_map_create_handle(&instance->context_map, - msg_context, - GFP_KERNEL); + /* Create an ID that will be passed along with our message so + * that when we service the VCHI reply, we can look up what + * message is being replied to. + */ + spin_lock(&instance->context_map_lock); + handle = idr_alloc(&instance->context_map, msg_context, + 0, 0, GFP_KERNEL); + spin_unlock(&instance->context_map_lock); - if (!msg_context->handle) { + if (handle < 0) { kfree(msg_context); - return ERR_PTR(-ENOMEM); + return ERR_PTR(handle); } + msg_context->instance = instance; + msg_context->handle = handle; + return msg_context; } static struct mmal_msg_context * -lookup_msg_context(struct vchiq_mmal_instance *instance, u32 handle) +lookup_msg_context(struct vchiq_mmal_instance *instance, int handle) { - return mmal_context_map_lookup_handle(&instance->context_map, - handle); + return idr_find(&instance->context_map, handle); } static void release_msg_context(struct mmal_msg_context *msg_context) { - mmal_context_map_destroy_handle(&msg_context->instance->context_map, - msg_context->handle); + struct vchiq_mmal_instance *instance = msg_context->instance; + + spin_lock(&instance->context_map_lock); + idr_remove(&instance->context_map, msg_context->handle); + spin_unlock(&instance->context_map_lock); kfree(msg_context); } @@ -1860,7 +1791,7 @@ int vchiq_mmal_finalise(struct vchiq_mmal_instance *instance) vfree(instance->bulk_scratch); - mmal_context_map_destroy(&instance->context_map); + idr_destroy(&instance->context_map); kfree(instance); @@ -1922,12 +1853,8 @@ int vchiq_mmal_init(struct vchiq_mmal_instance **out_instance) instance->bulk_scratch = vmalloc(PAGE_SIZE); - status = mmal_context_map_init(&instance->context_map); - if (status) { - pr_err("Failed to init context map (status=%d)\n", status); - kfree(instance); - return status; - } + spin_lock_init(&instance->context_map_lock); + idr_init_base(&instance->context_map, 1); params.callback_param = instance;