1 /* 2 * Copyright (c) 1990 University of Utah. 3 * Copyright (c) 1991, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * the Systems Programming Group of the University of Utah Computer 8 * Science Department. 9 * 10 * %sccs.include.redist.c% 11 * 12 * @(#)vm_pager.h 8.2 (Berkeley) 11/10/93 13 */ 14 15 /* 16 * Pager routine interface definition. 17 * For BSD we use a cleaner version of the internal pager interface. 18 */ 19 20 #ifndef _VM_PAGER_ 21 #define _VM_PAGER_ 22 23 struct pager_struct { 24 queue_head_t pg_list; /* links for list management */ 25 caddr_t pg_handle; /* external handle (vp, dev, fp) */ 26 int pg_type; /* type of pager */ 27 struct pagerops *pg_ops; /* pager operations */ 28 void *pg_data; /* private pager data */ 29 }; 30 31 /* pager types */ 32 #define PG_DFLT -1 33 #define PG_SWAP 0 34 #define PG_VNODE 1 35 #define PG_DEVICE 2 36 37 struct pagerops { 38 void (*pgo_init) /* Initialize pager. */ 39 __P((void)); 40 vm_pager_t (*pgo_alloc) /* Allocate pager. */ 41 __P((caddr_t, vm_size_t, vm_prot_t, vm_offset_t)); 42 void (*pgo_dealloc) /* Disassociate. */ 43 __P((vm_pager_t)); 44 int (*pgo_getpage) /* Get (read) page. */ 45 __P((vm_pager_t, vm_page_t, boolean_t)); 46 int (*pgo_putpage) /* Put (write) page. */ 47 __P((vm_pager_t, vm_page_t, boolean_t)); 48 boolean_t (*pgo_haspage) /* Does pager have page? */ 49 __P((vm_pager_t, vm_offset_t)); 50 }; 51 52 /* 53 * get/put return values 54 * OK operation was successful 55 * BAD specified data was out of the accepted range 56 * FAIL specified data was in range, but doesn't exist 57 * PEND operations was initiated but not completed 58 * ERROR error while accessing data that is in range and exists 59 */ 60 #define VM_PAGER_OK 0 61 #define VM_PAGER_BAD 1 62 #define VM_PAGER_FAIL 2 63 #define VM_PAGER_PEND 3 64 #define VM_PAGER_ERROR 4 65 66 #define VM_PAGER_ALLOC(h, s, p, o) (*(pg)->pg_ops->pgo_alloc)(h, s, p, o) 67 #define VM_PAGER_DEALLOC(pg) (*(pg)->pg_ops->pgo_dealloc)(pg) 68 #define VM_PAGER_GET(pg, m, s) (*(pg)->pg_ops->pgo_getpage)(pg, m, s) 69 #define VM_PAGER_PUT(pg, m, s) (*(pg)->pg_ops->pgo_putpage)(pg, m, s) 70 #define VM_PAGER_HASPAGE(pg, o) (*(pg)->pg_ops->pgo_haspage)(pg, o) 71 72 #ifdef KERNEL 73 extern struct pagerops *dfltpagerops; 74 75 vm_pager_t vm_pager_allocate 76 __P((int, caddr_t, vm_size_t, vm_prot_t, vm_offset_t)); 77 void vm_pager_deallocate __P((vm_pager_t)); 78 int vm_pager_get __P((vm_pager_t, vm_page_t, boolean_t)); 79 boolean_t vm_pager_has_page __P((vm_pager_t, vm_offset_t)); 80 void vm_pager_init __P((void)); 81 vm_pager_t vm_pager_lookup __P((queue_head_t *, caddr_t)); 82 vm_offset_t vm_pager_map_page __P((vm_page_t)); 83 int vm_pager_put __P((vm_pager_t, vm_page_t, boolean_t)); 84 void vm_pager_sync __P((void)); 85 void vm_pager_unmap_page __P((vm_offset_t)); 86 #endif 87 88 #endif /* _VM_PAGER_ */ 89