/*
 * Copyright © 2014 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use, copy,
 * modify, merge, publish, distribute, sublicense, and/or sell copies
 * of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including
 * the next paragraph) shall be included in all copies or substantial
 * portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */

#include "fmm.h"
#include "linux/kfd_ioctl.h"
#include "libhsakmt.h"
#include <stdlib.h>
#include <stdio.h>
#include <inttypes.h>
#include <sys/mman.h>

#define NON_VALID_GPU_ID 0
#define ARRAY_LEN(array) (sizeof(array) / sizeof(array[0]))
#define INIT_APERTURE(base_value, limit_value) {.base = (void*)base_value, .limit = (void*)limit_value }
#define INIT_MANAGEBLE_APERTURE(base_value, limit_value) {.base = (void*)base_value,.limit = (void*)limit_value, .vm_ranges = NULL, .vm_objects = NULL, .fmm_mutex = PTHREAD_MUTEX_INITIALIZER}
#define INIT_GPU_MEM \
{		.gpu_id = NON_VALID_GPU_ID,\
		.lds_aperture = INIT_APERTURE(0, 0), \
		.scratch_aperture = INIT_MANAGEBLE_APERTURE(0, 0),\
		.gpuvm_aperture =  INIT_MANAGEBLE_APERTURE(0, 0)\
}

#define INIT_GPUs_MEM {[0 ... (NUM_OF_SUPPORTED_GPUS-1)] = INIT_GPU_MEM}
struct vm_object{
	void* start;
	HSAuint64 size;
	HSAuint64 handle; // opaque
	struct vm_object* next;
	struct vm_object* prev;
};
typedef struct vm_object vm_object_t;

struct vm_area{
	void* start;
	void* end;
	struct vm_area* next;
	struct vm_area* prev;
};
typedef struct vm_area vm_area_t;

typedef struct {
	void* base;
	void* limit;
	vm_area_t* vm_ranges;
	vm_object_t* vm_objects;
	pthread_mutex_t fmm_mutex;
} manageble_aperture_t;

typedef struct {
	void* base;
	void* limit;
} aperture_t;

typedef struct{
	HSAuint32 gpu_id;
	aperture_t lds_aperture;
	manageble_aperture_t scratch_aperture;
	manageble_aperture_t gpuvm_aperture;
}gpu_mem_t;

static gpu_mem_t gpu_mem[] = INIT_GPUs_MEM;

static vm_area_t* vm_create_and_init_area(void* start, void* end){
	vm_area_t* area = (vm_area_t*)malloc(sizeof(vm_area_t));// TODO: Memory pool ???
	if (area){
		area->start = start;
		area->end = end;
		area->next = area->prev = NULL;
	}

	return area;
}

static vm_object_t* vm_create_and_init_object(void* start, uint64_t size, uint64_t handle){
	vm_object_t* object = (vm_object_t*)malloc(sizeof(vm_object_t)); // TODO: Memory pool ???
	if (object){
		object->start = start;
		object->size = size;
		object->handle = handle;
		object->next = object->prev = NULL;
	}

	return object;
}


static void vm_remove_area(manageble_aperture_t* app, vm_area_t* area){
	vm_area_t* next;
	vm_area_t* prev;

	next = area->next;
	prev = area->prev;

	if (prev == NULL )// The first element
		app->vm_ranges = next;
	else
		prev->next = next;

	if(next) // If not the last element
		next->prev = prev;

	free(area);

}

static void vm_remove_object(manageble_aperture_t* app, vm_object_t* object){
	vm_object_t* next;
	vm_object_t* prev;

	next = object->next;
	prev = object->prev;

	if (prev == NULL )// The first element
		app->vm_objects = next;
	else
		prev->next = next;

	if(next) // If not the last element
		next->prev = prev;

	free(object);

}



static void vm_add_area_after(vm_area_t* after_this, vm_area_t* new_area){
	vm_area_t* next = after_this->next;
	after_this->next = new_area;
	new_area->next = next;

	new_area->prev = after_this;
	if (next)
		next->prev = new_area;
}

static void vm_add_object_before(vm_object_t* before_this, vm_object_t* new_object){
	vm_object_t* prev = before_this->prev;
	before_this->prev = new_object;
	new_object->next = before_this;

	new_object->prev = prev;
	if (prev)
		prev->next = new_object;
}

static void vm_split_area(manageble_aperture_t* app, vm_area_t* area, void* address, uint64_t MemorySizeInBytes){

	// The existing area is split to: [area->start, address - 1] and [address + MemorySizeInBytes, area->end]
	vm_area_t* new_area = vm_create_and_init_area(VOID_PTR_ADD(address,MemorySizeInBytes), area->end);

	// Shrink the existing area
	area->end = VOID_PTR_SUB(address,1);

	vm_add_area_after(area, new_area);

}

static vm_object_t* vm_find_object_by_address(manageble_aperture_t* app, void* address, uint64_t size){
	vm_object_t* cur = app->vm_objects;

	// Look up the appropriate address range containing the given address
	while(cur){
		if(cur->start == address && cur->size == size)
			break;
		cur = cur->next;
	};

	return cur; // NULL if not found
}

static vm_area_t* vm_find(manageble_aperture_t* app, void* address){
	vm_area_t* cur = app->vm_ranges;

	// Look up the appropriate address range containing the given address
	while(cur){
		if(cur->start <= address && cur->end >= address)
			break;
		cur = cur->next;
	};

	return cur; // NULL if not found
}

static bool aperture_is_valid(void* app_base, void* app_limit){
	if (app_base && app_limit && app_base < app_limit)
		return true;
	return false;
}

/*
 * Assumes that fmm_mutex is locked on entry.
 */
static int aperture_release(manageble_aperture_t* app, void* address, uint64_t MemorySizeInBytes)
{
	vm_object_t* object;
	vm_area_t* area;
	int rc = -1;

	area = vm_find(app, address);
	object = vm_find_object_by_address(app, address, MemorySizeInBytes);
	if (object && area){
		vm_remove_object(app, object);
		if (VOID_PTRS_SUB(area->end, area->start) + 1 > MemorySizeInBytes){ // the size of the released block is less than the size of area
			if (area->start == address){ // shrink from the start
				area->start = VOID_PTR_ADD(area->start,MemorySizeInBytes);
			} else if (VOID_PTRS_SUB(area->end, address) + 1 == MemorySizeInBytes){ // shrink from the end
				area->end = VOID_PTR_SUB(area->end, MemorySizeInBytes);
			} else { // split the area
				vm_split_area(app, area, address, MemorySizeInBytes);
			}
			rc = 0;
		} else if (VOID_PTRS_SUB(area->end, area->start) + 1 == MemorySizeInBytes){ // the size of the released block is exactly the same as the size of area
			vm_remove_area(app, area);
			rc = 0;
		} else {
			//Inconsistent data. Fail it?
			rc = -1;
		}
	}

	return rc;
}

/*
 * returns allocated address or NULL. Assumes, that fmm_mutex is locked on entry.
 */
static void* aperture_allocate(manageble_aperture_t* app, uint64_t MemorySizeInBytes){
	vm_area_t* cur, *next, *new_area, *start;
	vm_object_t* new_object;
	void* new_address = NULL;
	next = NULL;
	new_area = NULL;

	cur = app->vm_ranges;
	if (cur){ // not empty

		// Look up the appropriate address space "hole" or end of the list
		while(cur){
			next = cur->next;

			// End of the list reached
			if (!next)
				break;

			// address space "hole"
			if ((VOID_PTRS_SUB(next->start,cur->end) >= MemorySizeInBytes))
				break;

			cur = next;
		};

		// If the new range is inside the reserved aperture
		if (VOID_PTRS_SUB(app->limit, cur->end) + 1 >= MemorySizeInBytes){
			// cur points to the last inspected element: the tail of the list or the found "hole"
			// Just extend the existing region
			new_address = VOID_PTR_ADD(cur->end, 1);
			cur->end = VOID_PTR_ADD(cur->end, MemorySizeInBytes);
		} else
			new_address = NULL;

	} else { // empty - create the first area
		start = (void*)app->base;
		new_area = vm_create_and_init_area(start, VOID_PTR_ADD(start, (MemorySizeInBytes - 1)));
		if (new_area){
			app->vm_ranges = new_area;
			new_address = new_area->start;
		}
	}

	// Allocate new object
	if (new_address){
		new_object = vm_create_and_init_object(new_address, MemorySizeInBytes, 0);
		if (new_object){
			if (app->vm_objects == NULL){ // empty list
				// Update head
				app->vm_objects = new_object;
			} else {
				// Add it before the first element
				vm_add_object_before(app->vm_objects, new_object);
				// Update head
				app->vm_objects = new_object;
			}
		} else{
			// Failed to allocate object: remove just allocated range and return NULL
			aperture_release(app, new_address, MemorySizeInBytes);
			new_address = NULL;
		}
	}

	return new_address;

}



static int32_t gpu_mem_find_by_gpu_id(uint32_t gpu_id){
	int32_t i;

	for(i = 0; i < NUM_OF_SUPPORTED_GPUS; i++){
		if(gpu_mem[i].gpu_id == gpu_id)
			return i;
	}

	return -1;
}

bool fmm_is_inside_some_aperture(void* address){

	int32_t i;

	for(i = 0; i < NUM_OF_SUPPORTED_GPUS; i++){
		if(gpu_mem[i].gpu_id != NON_VALID_GPU_ID){
			if ((address>= gpu_mem[i].lds_aperture.base) && (address<= gpu_mem[i].lds_aperture.limit))
				return true;
			if ((address>= gpu_mem[i].gpuvm_aperture.base) && (address<= gpu_mem[i].gpuvm_aperture.limit))
				return true;
			if ((address>= gpu_mem[i].scratch_aperture.base) && (address<= gpu_mem[i].scratch_aperture.limit))
				return true;
		}
	}

	return false;
}

#ifdef DEBUG_PRINT_APERTURE
static void aperture_print(aperture_t* app){
	printf("\t Base: %p\n", app->base);
	printf("\t Limit: %p\n", app->limit);
}

static void manageble_aperture_print(manageble_aperture_t* app){
	vm_area_t* cur = app->vm_ranges;
	vm_object_t *object = app->vm_objects;

	printf("\t Base: %p\n", app->base);
	printf("\t Limit: %p\n", app->limit);
	printf("\t Ranges: \n");
	while(cur){
		printf("\t\t Range [%p - %p] \n", cur->start, cur->end);
		cur = cur->next;
	};
	printf("\t Objects: \n");
	while(object){
		printf("\t\t Object [%p - %" PRIu64 "] \n", object->start, object->size);
		object = object->next;
	};
}

void fmm_print(uint32_t gpu_id){
	int32_t i = gpu_mem_find_by_gpu_id(gpu_id);
	if(i >= 0){ // Found
		printf("LDS aperture: \n");
		aperture_print(&gpu_mem[i].lds_aperture);
		printf("GPUVM aperture: \n");
		manageble_aperture_print(&gpu_mem[i].gpuvm_aperture);
		printf("Scratch aperture: \n");
		manageble_aperture_print(&gpu_mem[i].scratch_aperture);

	}
}
#else
void fmm_print(uint32_t gpu_id){

}
#endif


void* fmm_allocate_scratch(uint32_t gpu_id, uint64_t MemorySizeInBytes){

	void* mem = NULL;
	int32_t i = gpu_mem_find_by_gpu_id(gpu_id);

	// If not found or aperture isn't properly initialized/supported
	if(i < 0 || !aperture_is_valid(gpu_mem[i].scratch_aperture.base, gpu_mem[i].scratch_aperture.limit))
		return NULL;

        pthread_mutex_lock(&gpu_mem[i].scratch_aperture.fmm_mutex);
	mem = aperture_allocate(&gpu_mem[i].scratch_aperture, MemorySizeInBytes);
        pthread_mutex_unlock(&gpu_mem[i].scratch_aperture.fmm_mutex);

	return mem;
}

void* fmm_allocate_device(uint32_t gpu_id, uint64_t MemorySizeInBytes){

	void* mem = NULL;
	int32_t i = gpu_mem_find_by_gpu_id(gpu_id);

	// If not found or aperture isn't properly initialized/supported
	if(i < 0 || !aperture_is_valid(gpu_mem[i].gpuvm_aperture.base, gpu_mem[i].gpuvm_aperture.limit))
		return NULL;

	pthread_mutex_lock(&gpu_mem[i].gpuvm_aperture.fmm_mutex);
	mem = aperture_allocate(&gpu_mem[i].gpuvm_aperture, MemorySizeInBytes);
        pthread_mutex_unlock(&gpu_mem[i].gpuvm_aperture.fmm_mutex);

	return mem;
}


int fmm_release(void* address, uint64_t MemorySizeInBytes){

	uint32_t i;
	int32_t rc = -1;

	for(i = 0; i < NUM_OF_SUPPORTED_GPUS; i++){
		if(gpu_mem[i].gpu_id == NON_VALID_GPU_ID)
			continue;

		if (address >= gpu_mem[i].gpuvm_aperture.base && address <= gpu_mem[i].gpuvm_aperture.limit){
	        pthread_mutex_lock(&gpu_mem[i].gpuvm_aperture.fmm_mutex);
			rc = aperture_release(&gpu_mem[i].gpuvm_aperture, address, MemorySizeInBytes);
	        pthread_mutex_unlock(&gpu_mem[i].gpuvm_aperture.fmm_mutex);
			fmm_print(gpu_mem[i].gpu_id);
		} else if (address >= gpu_mem[i].scratch_aperture.base && address <= gpu_mem[i].scratch_aperture.limit)
	        pthread_mutex_lock(&gpu_mem[i].scratch_aperture.fmm_mutex);
			rc = aperture_release(&gpu_mem[i].scratch_aperture, address, MemorySizeInBytes);
			pthread_mutex_unlock(&gpu_mem[i].scratch_aperture.fmm_mutex);
	}

	return rc;
}

HSAKMT_STATUS fmm_init_process_apertures(){
	struct kfd_ioctl_get_process_apertures_args args;
	uint8_t node_id;

	if (0 == kmtIoctl(kfd_fd, AMDKFD_IOC_GET_PROCESS_APERTURES, (void*)&args)){
		for(node_id = 0; node_id < args.num_of_nodes; node_id++){
			gpu_mem[node_id].gpu_id = args.process_apertures[node_id].gpu_id;
			gpu_mem[node_id].lds_aperture.base = PORT_UINT64_TO_VPTR(args.process_apertures[node_id].lds_base);
			gpu_mem[node_id].lds_aperture.limit = PORT_UINT64_TO_VPTR(args.process_apertures[node_id].lds_limit);
			gpu_mem[node_id].gpuvm_aperture.base = PORT_UINT64_TO_VPTR(args.process_apertures[node_id].gpuvm_base);
			gpu_mem[node_id].gpuvm_aperture.limit = PORT_UINT64_TO_VPTR(args.process_apertures[node_id].gpuvm_limit);
			gpu_mem[node_id].scratch_aperture.base = PORT_UINT64_TO_VPTR(args.process_apertures[node_id].scratch_base);
			gpu_mem[node_id].scratch_aperture.limit = PORT_UINT64_TO_VPTR(args.process_apertures[node_id].scratch_limit);
		}

		return HSAKMT_STATUS_SUCCESS;
	}

	return HSAKMT_STATUS_ERROR;

}

HSAuint64 fmm_get_aperture_base(aperture_type_e aperture_type, HSAuint32 gpu_id){
	int32_t slot = gpu_mem_find_by_gpu_id(gpu_id);
	if (slot<0)
		return HSAKMT_STATUS_INVALID_PARAMETER;

	switch(aperture_type){
	case FMM_GPUVM:
		return aperture_is_valid(gpu_mem[slot].gpuvm_aperture.base, gpu_mem[slot].gpuvm_aperture.limit) ? PORT_VPTR_TO_UINT64(gpu_mem[slot].gpuvm_aperture.base) : 0;
		break;
	case FMM_SCRATCH:
		return aperture_is_valid(gpu_mem[slot].scratch_aperture.base, gpu_mem[slot].scratch_aperture.limit) ? PORT_VPTR_TO_UINT64(gpu_mem[slot].scratch_aperture.base) : 0;
		break;
	case FMM_LDS:
		return aperture_is_valid(gpu_mem[slot].lds_aperture.base, gpu_mem[slot].lds_aperture.limit) ? PORT_VPTR_TO_UINT64(gpu_mem[slot].lds_aperture.base) : 0;
		break;
	default:
		return 0;
	}

}