/* @(#)seg.h 1.1 92/07/30 SMI */
/*
* Copyright (c) 1988 by Sun Microsystems, Inc.
*/
#ifndef _vm_seg_h
#define _vm_seg_h
#include <vm/faultcode.h>
#include <vm/mp.h>
/*
* VM - Segments.
*/
/*
* An address space contains a set of segments, managed by drivers.
* Drivers support mapped devices, sharing, copy-on-write, etc.
*
* The seg structure contains a lock to prevent races, the base virtual
* address and size of the segment, a back pointer to the containing
* address space, pointers to maintain a circularly doubly linked list
* of segments in the same address space, and procedure and data hooks
* for the driver. The seg list on the address space is sorted by
* ascending base addresses and overlapping segments are not allowed.
*
* After a segment is created, faults may occur on pages of the segment.
* When a fault occurs, the fault handling code must get the desired
* object and set up the hardware translation to the object. For some
* objects, the fault handling code also implements copy-on-write.
*
* When the hat wants to unload a translation, it can call the unload
* routine which is responsible for processing reference and modify bits.
*/
struct seg {
kmon_t s_lock;
addr_t s_base; /* base virtual address */
u_int s_size; /* size in bytes */
struct as *s_as; /* containing address space */
struct seg *s_next; /* next seg in this address space */
struct seg *s_prev; /* prev seg in this address space */
struct seg_ops {
int (*dup)(/* seg, newsegp */);
int (*unmap)(/* seg, addr, len */);
int (*free)(/* seg */);
faultcode_t (*fault)(/* seg, addr, len, type, rw */);
faultcode_t (*faulta)(/* seg, addr */);
int (*hatsync)(/* seg, addr, ref, mod, flags */);
int (*setprot)(/* seg, addr, size, prot */);
int (*checkprot)(/* seg, addr, size, prot */);
int (*kluster)(/* seg, addr, delta */);
u_int (*swapout)(/* seg */);
int (*sync)(/* seg, addr, size, flags */);
int (*incore)(/* seg, addr, size, vec */);
int (*lockop)(/* seg, addr, size, op */);
int (*advise)(/* seg, addr, size, behav */);
} *s_ops;
caddr_t s_data; /* private data for instance */
};
/*
* Fault information passed to the seg fault handling routine.
* The F_SOFTLOCK and F_SOFTUNLOCK are used by software
* to lock and unlock pages for physical I/O.
*/
enum fault_type {
F_INVAL, /* invalid page */
F_PROT, /* protection fault */
F_SOFTLOCK, /* software requested locking */
F_SOFTUNLOCK, /* software requested unlocking */
};
/*
* seg_rw gives the access type for a fault operation
*/
enum seg_rw {
S_OTHER, /* unknown or not touched */
S_READ, /* read access attempted */
S_WRITE, /* write access attempted */
S_EXEC, /* execution access attempted */
};
#ifdef KERNEL
/*
* Generic segment operations
*/
struct seg *seg_alloc(/* as, base, size */);
int seg_attach(/* as, base, size, seg */);
void seg_free(/* seg */);
u_int seg_page(/* seg, addr */);
u_int seg_pages(/* seg */);
#endif KERNEL
#endif /*!_vm_seg_h*/
