Commit 854f1a37 authored by Léo Grange's avatar Léo Grange
Browse files

implement memory area manipulation functions

parent 5c141032

sys/mem_area.c

0 → 100644
+104 −0
Original line number Diff line number Diff line 
#include "mem_area.h"

#include <sys/process.h>

#include <utils/pool_alloc.h>

#include <fs/vfs_file.h>

#include <utils/log.h>





// pool allocation data

static struct pool_alloc _mem_area_pool = POOL_INIT(struct mem_area);





void mem_area_init() {

	printk(LOG_DEBUG, "mem_area: area/page=%d\n", _mem_area_pool.perpage);

}





struct mem_area *mem_area_alloc() {

	struct mem_area *ret;



	ret = pool_alloc(&_mem_area_pool);

	if(ret != NULL) {

		ret->flags = 0;

		ret->address = NULL;

		ret->max_size = 0;

	}



	return ret;

}



void mem_area_free(struct mem_area *area) {

	pool_free(&_mem_area_pool, area);

}





struct mem_area *mem_area_find(struct process *proc, void *address) {

	// for now, the list is not sorted, so check for each

	struct list_head *cur;

	struct mem_area *ret = NULL;



	list_for_each(cur, &(proc->mem_areas)) {

		// check if address is inside this area

		struct mem_area *area = container_of(cur, struct mem_area, list);

		if(address >= area->address && address < (area->address + area->max_size)) {

			ret = area;

			break;

		}

	}



	return ret;

}





/**

 * internal function, check if an area is defined in the given address range

 * Return 0 if this range is empty, 1 if an area exists.

 */

static int mem_area_check_range(struct process *proc, void *addr_begin, size_t size) {

	struct list_head *cur;



	list_for_each(cur, &(proc->mem_areas)) {

		// check if address range intersects with this area

		struct mem_area *area = container_of(cur, struct mem_area, list);

		if(area->address < (addr_begin + size)

				&& (area->address + area->max_size) > addr_begin)

			return 1;

	}



	return 0;

}





int mem_area_insert(struct process *proc, struct mem_area *area) {

	// check for any overlayed area

	if(!mem_area_check_range(proc, area->address, area->max_size)) {

		// not sorted, insert in front

		list_push_front(& proc->mem_areas, & area->list);

		return 0;

	}



	printk(LOG_ERR, "mem_area: unable to insert area (overlay)\n");

	return -1;

}





int mem_area_copy_raw(struct mem_area *area, size_t offset, void *dest, size_t size) {

	int ret = -1;



	if(area->flags & MEM_AREA_TYPE_ANON) {

		// anonymous area, the current implementation do nothing...

		ret = 0;

	}

	else if(area->flags & MEM_AREA_TYPE_FILE) {

		// file mapped to memory, for now use a generic way to handle them

		// TODO improve this with map_area_ops struct to allow "override"

		size_t nbread;



		vfs_lseek(area->file.filep, SEEK_SET, offset);

		nbread = vfs_read(area->file.filep, dest, size);

		ret = nbread == size ? 0 : -1;

	}



	return ret;

}

sys/mem_area.h

+2 −1
Original line number Diff line number Diff line
@@ -31,7 +31,7 @@ struct mem_area { 
	union {

		struct {

			// file structure of the file mapped to this area

			struct file *f;

			struct file *filep;



			// origin's position in the file

			size_t origin;
@@ -61,6 +61,7 @@ void mem_area_init(); 
 * Return a newly allocated memory area, not initialized.

 */

struct mem_area *mem_area_alloc();

void mem_area_free(struct mem_area *area);





/**

sys/process.c

+2 −2
Original line number Diff line number Diff line
@@ -8,7 +8,7 @@ 
#include <utils/bitfield.h>

#include <interface/fixos/fcntl.h>

#include <interface/fixos/errno.h>

#include <sys/mem_areas.h>

#include <sys/mem_area.h>



#include <loader/elfloader/loader.h>

#include <fs/vfs_file.h>
@@ -111,7 +111,7 @@ struct process *process_alloc() { 


			arch_adrsp_init(& proc->addr_space);

			proc->dir_list = NULL;

			INIT_LIST_HEAD(proc->mem_areas);

			INIT_LIST_HEAD(& proc->mem_areas);





			sigemptyset(& proc->sig_blocked);

sys/subdir.mk

+2 −1
Original line number Diff line number Diff line
@@ -12,7 +12,8 @@ C_SRC_L:= \ 
	kdebug.c \

	sysctl.c \

	waitqueue.c \

	tty.c

	tty.c \

	mem_area.c





CURDIR:=sys