Commit a9f7de98 authored by Léo Grange's avatar Léo Grange
Browse files

improve memory areas integration

parent 61093179

fs/casio_smemfs/file.c

+22 −4
Original line number Diff line number Diff line
@@ -4,17 +4,21 @@ 
#include <fs/inode.h>

#include <interface/fixos/errno.h>

#include "smemfs_primitives_ng.h"

// used for memory areas...

#include <fs/vfs_file.h>





const struct file_operations smemfs_file_operations = {

	.release = smemfs_release,

	.read = smemfs_read,

	.lseek = smemfs_lseek

	.lseek = smemfs_lseek,

	.map_area = smemfs_map_area

};





const struct mem_area_ops smemfs_mem_ops = {

	.area_pagefault = smemfs_area_pagefault

	.area_pagefault = smemfs_area_pagefault,

	.area_release = smemfs_area_release

};
@@ -140,6 +144,17 @@ off_t smemfs_lseek (struct file *filep, off_t offset, int whence) { 
}







int smemfs_map_area(struct file *filep, struct mem_area *area) {

	// not a lot of stuff to do for now...

	area->ops = &smemfs_mem_ops;

	area->file.filep = filep;

	// increase file usage count (mirrored in smemfs_area_release)

	filep->count++;

	return 0;

}





union pm_page smemfs_area_pagefault(struct mem_area *area, void *addr_fault) {

	size_t readsize;

	void *pmaddr;
@@ -179,10 +194,13 @@ union pm_page smemfs_area_pagefault(struct mem_area *area, void *addr_fault) { 
	return pmpage;

}



int smemfs_area_resize(struct mem_area *area, const struct mem_area *new_area) {

/*

int smemfs_area_resize(struct mem_area *area, size_t new_size) {

	return -1;

}

*/



void smemfs_area_release(struct mem_area *area) {



	// release the file, by closing it at vfs level?

	vfs_close(area->file.filep);

}

fs/casio_smemfs/file.h

+2 −0
Original line number Diff line number Diff line
@@ -24,6 +24,8 @@ off_t smemfs_lseek (struct file *filep, off_t offset, int whence); 




// memory-mapped operations

int smemfs_map_area(struct file *filep, struct mem_area *area);



union pm_page smemfs_area_pagefault(struct mem_area *area, void *addr_fault);



int smemfs_area_resize(struct mem_area *area, const struct mem_area *new_area);

fs/file_operations.h

+20 −0
Original line number Diff line number Diff line
@@ -15,6 +15,8 @@ 


struct file;



struct mem_area;



struct file_operations {

	/**

	 * Release the file opened instance ("close" it).
@@ -47,6 +49,24 @@ struct file_operations { 
	 * data is specific to command and device, may be not used.

	 */

	int (*ioctl) (struct file *filep, int cmd, void *data);





	/**

	 * Create a memory map of this object in memory.

	 * Devices may use it as they want to, for example to provide big buffers

	 * shared with userland.

	 * area should be set with all non-private fields having a valid value,

	 * which is not very well defined...

	 * At least field ops is not expected to be set, but the interface is not

	 * well designed for now.

	 * TODO either use a 'hints' argument with mem_area-like type, or define

	 * exactly what should be set and what is set by this function itself

	 *

	 * NULL if device of filesystem do not implements memory mapped areas.

	 *

	 * Return 0 if mapping is accepted, negative value else.

	 */

	int (*map_area) (struct file *filep, struct mem_area *area);

};



#endif //_FS_FILE_OPERATIONS_H

fs/vfs_file.c

+36 −0
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ 
#include "file_system.h"

#include "file_operations.h"

#include "vfs_directory.h"

#include <sys/mem_area.h>





// pool allocation for file struct
@@ -157,3 +158,38 @@ int vfs_fstat(struct file *filep, struct stat *buf) { 
		return -1;

	}

}





int vfs_map_area(struct file *filep, size_t size, size_t offset, void *address,

		int flags, size_t infile_size, struct process *proc)

{

	int ret = -EINVAL;



	if(filep->op->map_area != NULL) {

		struct mem_area *area;

		area = mem_area_alloc();

		if(area == NULL) {

			ret = -ENOMEM;

		}

		else {

			// prepare area struct from arguments

			area->address = address;

			area->max_size = size;

			area->flags = flags | MEM_AREA_TYPE_FILE;

			area->file.base_offset = offset;

			area->file.infile_size = (flags & MEM_AREA_PARTIAL) ? infile_size : size;

			area->file.filep = filep;

			

			ret = filep->op->map_area(filep, area);

			if(ret == 0) {

				ret = mem_area_insert(proc, area);

			}

			else {

				// failed, free area (do not *release* it, free directly)

				mem_area_free(area);

			}

		}

	}

	

	return ret;

}

fs/vfs_file.h

+14 −0
Original line number Diff line number Diff line
@@ -90,4 +90,18 @@ int vfs_ioctl(struct file *filep, int cmd, void *data); 
int vfs_fstat(struct file *filep, struct stat *buf);





struct process;



/**

 * Map size bytes of the object in memory, from given offset, to given address

 * in the address space of a given process.

 * Area permissions, and additionnal flags, may be provided, using constants

 * from sys/mem_area.h

 * from_file is important only if flag contains MEM_AREA_PARTIAL

 *

 * TODO make a 'hints' structure to reduce number of arguments?

 */

int vfs_map_area(struct file *filep, size_t size, size_t offset, void *address,

		int flags, size_t infile_size, struct process *proc);



#endif //_FS_VFS_FILE_H