pipe.h

/*
 * Copyright (C) 2001,2002,2003 Philippe Gerum.
 *
 * Xenomai is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published
 * by the Free Software Foundation, Inc., 675 Mass Ave, Cambridge MA
 * 02139, USA; either version 2 of the License, or (at your option)
 * any later version.
 *
 * Xenomai is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */
#ifndef _COBALT_KERNEL_PIPE_H
#define _COBALT_KERNEL_PIPE_H
 
#include <linux/types.h>
#include <linux/poll.h>
#include <cobalt/kernel/synch.h>
#include <cobalt/kernel/thread.h>
#include <cobalt/uapi/kernel/pipe.h>
 
#define XNPIPE_NDEVS      CONFIG_XENO_OPT_PIPE_NRDEV
#define XNPIPE_DEV_MAJOR  150
 
#define XNPIPE_KERN_CONN         0x1
#define XNPIPE_KERN_LCLOSE       0x2
#define XNPIPE_USER_CONN         0x4
#define XNPIPE_USER_SIGIO        0x8
#define XNPIPE_USER_WREAD        0x10
#define XNPIPE_USER_WREAD_READY  0x20
#define XNPIPE_USER_WSYNC        0x40
#define XNPIPE_USER_WSYNC_READY  0x80
#define XNPIPE_USER_LCONN        0x100
 
#define XNPIPE_USER_ALL_WAIT \
(XNPIPE_USER_WREAD|XNPIPE_USER_WSYNC)
 
#define XNPIPE_USER_ALL_READY \
(XNPIPE_USER_WREAD_READY|XNPIPE_USER_WSYNC_READY)
 
struct xnpipe_mh {
        size_t size;
        size_t rdoff;
        struct list_head link;
};
 
struct xnpipe_state;
 
struct xnpipe_operations {
        void (*output)(struct xnpipe_mh *mh, void *xstate);
        int (*input)(struct xnpipe_mh *mh, int retval, void *xstate);
        void *(*alloc_ibuf)(size_t size, void *xstate);
        void (*free_ibuf)(void *buf, void *xstate);
        void (*free_obuf)(void *buf, void *xstate);
        void (*release)(void *xstate);
};
 
struct xnpipe_state {
        struct list_head slink; /* Link on sleep queue */
        struct list_head alink; /* Link on async queue */
 
        struct list_head inq;           /* From user-space to kernel */
        int nrinq;
        struct list_head outq;          /* From kernel to user-space */
        int nroutq;
        struct xnsynch synchbase;
        struct xnpipe_operations ops;
        void *xstate;           /* Extra state managed by caller */
 
        /* Linux kernel part */
        unsigned long status;
        struct fasync_struct *asyncq;
        wait_queue_head_t readq;        /* open/read/poll waiters */
        wait_queue_head_t syncq;        /* sync waiters */
        int wcount;                     /* number of waiters on this minor */
        size_t ionrd;
};
 
extern struct xnpipe_state xnpipe_states[];
 
#define xnminor_from_state(s) (s - xnpipe_states)
 
#ifdef CONFIG_XENO_OPT_PIPE
int xnpipe_mount(void);
void xnpipe_umount(void);
#else /* !CONFIG_XENO_OPT_PIPE */
static inline int xnpipe_mount(void) { return 0; }
static inline void xnpipe_umount(void) { }
#endif /* !CONFIG_XENO_OPT_PIPE */
 
/* Entry points of the kernel interface. */
 
int xnpipe_connect(int minor,
                   struct xnpipe_operations *ops, void *xstate);
 
int xnpipe_disconnect(int minor);
 
ssize_t xnpipe_send(int minor,
                    struct xnpipe_mh *mh, size_t size, int flags);
 
ssize_t xnpipe_mfixup(int minor, struct xnpipe_mh *mh, ssize_t size);
 
ssize_t xnpipe_recv(int minor,
                    struct xnpipe_mh **pmh, xnticks_t timeout);
 
int xnpipe_flush(int minor, int mode);
 
int xnpipe_pollstate(int minor, unsigned int *mask_r);
 
static inline unsigned int __xnpipe_pollstate(int minor)
{
        struct xnpipe_state *state = xnpipe_states + minor;
        unsigned int mask = POLLOUT;
 
        if (!list_empty(&state->inq))
                mask |= POLLIN;
 
        return mask;
}
 
static inline char *xnpipe_m_data(struct xnpipe_mh *mh)
{
        return (char *)(mh + 1);
}
 
#define xnpipe_m_size(mh) ((mh)->size)
 
#define xnpipe_m_rdoff(mh) ((mh)->rdoff)
 
#endif /* !_COBALT_KERNEL_PIPE_H */