freebsd-nq/sys/fs/cuse/cuse_ioctl.h
Hans Petter Selasky 56c49c63e7 Allow CUSE(3) to free all memory mapped memory by using regular SWAP objects
instead of malloc(). The SWAP objects are automagically freed when there are no
more consumers. This greatly simplifies the mmap logic inside CUSE(3) in the
kernel. This change fixes an issue where mmapped memory can accumulate and never
get freed, if many different mmap sizes are needed over time. Further this
change fixes memory leaks when the CUSE(3) kernel module is unloaded.

While at it make sure the CUSE_ALLOC_PAGES_MAX limit is treated as an exclusive
limit. CUSE(3) memory maps must be less than CUSE_ALLOC_PAGES_MAX number of pages.

Reviewed by:		kib @
Differential Revision:	https://reviews.freebsd.org/D11392
Sponsored by:		Mellanox Technologies
MFC after:		1 week
2017-11-03 14:10:57 +00:00

90 lines
3.2 KiB
C

/* $FreeBSD$ */
/*-
* Copyright (c) 2014 Hans Petter Selasky. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifndef _CUSE_IOCTL_H_
#define _CUSE_IOCTL_H_
#include <sys/ioccom.h>
#include <sys/types.h>
#define CUSE_BUFFER_MAX PAGE_SIZE
#define CUSE_DEVICES_MAX 64 /* units */
#define CUSE_BUF_MIN_PTR 0x10000UL
#define CUSE_BUF_MAX_PTR 0x20000UL
#define CUSE_ALLOC_UNIT_MAX 128 /* units */
/* All memory allocations must be less than the following limit */
#define CUSE_ALLOC_PAGES_MAX (((16UL * 1024UL * 1024UL) + PAGE_SIZE - 1) / PAGE_SIZE)
struct cuse_dev;
struct cuse_data_chunk {
uintptr_t local_ptr;
uintptr_t peer_ptr;
unsigned long length;
};
struct cuse_alloc_info {
unsigned long page_count;
unsigned long alloc_nr;
};
struct cuse_command {
struct cuse_dev *dev;
unsigned long fflags;
uintptr_t per_file_handle;
uintptr_t data_pointer;
unsigned long argument;
unsigned long command; /* see CUSE_CMD_XXX */
};
struct cuse_create_dev {
struct cuse_dev *dev;
uid_t user_id;
gid_t group_id;
int permissions;
char devname[80]; /* /dev/xxxxx */
};
/* Definition of internal IOCTLs for /dev/cuse */
#define CUSE_IOCTL_GET_COMMAND _IOR('C', 0, struct cuse_command)
#define CUSE_IOCTL_WRITE_DATA _IOW('C', 1, struct cuse_data_chunk)
#define CUSE_IOCTL_READ_DATA _IOW('C', 2, struct cuse_data_chunk)
#define CUSE_IOCTL_SYNC_COMMAND _IOW('C', 3, int)
#define CUSE_IOCTL_GET_SIG _IOR('C', 4, int)
#define CUSE_IOCTL_ALLOC_MEMORY _IOW('C', 5, struct cuse_alloc_info)
#define CUSE_IOCTL_FREE_MEMORY _IOW('C', 6, struct cuse_alloc_info)
#define CUSE_IOCTL_SET_PFH _IOW('C', 7, uintptr_t)
#define CUSE_IOCTL_CREATE_DEV _IOW('C', 8, struct cuse_create_dev)
#define CUSE_IOCTL_DESTROY_DEV _IOW('C', 9, struct cuse_dev *)
#define CUSE_IOCTL_ALLOC_UNIT _IOR('C',10, int)
#define CUSE_IOCTL_FREE_UNIT _IOW('C',11, int)
#define CUSE_IOCTL_SELWAKEUP _IOW('C',12, int)
#define CUSE_IOCTL_ALLOC_UNIT_BY_ID _IOWR('C',13, int)
#define CUSE_IOCTL_FREE_UNIT_BY_ID _IOWR('C',14, int)
#endif /* _CUSE_IOCTL_H_ */