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 8.5 (Berkeley) 07/07/94 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 TAILQ_HEAD(pagerlst, pager_struct); 24 25 struct pager_struct { 26 TAILQ_ENTRY(pager_struct) pg_list; /* links for list management */ 27 caddr_t pg_handle; /* ext. handle (vp, dev, fp) */ 28 int pg_type; /* type of pager */ 29 int pg_flags; /* flags */ 30 struct pagerops *pg_ops; /* pager operations */ 31 void *pg_data; /* private pager data */ 32 }; 33 34 /* pager types */ 35 #define PG_DFLT -1 36 #define PG_SWAP 0 37 #define PG_VNODE 1 38 #define PG_DEVICE 2 39 40 /* flags */ 41 #define PG_CLUSTERGET 1 42 #define PG_CLUSTERPUT 2 43 44 struct pagerops { 45 void (*pgo_init) /* Initialize pager. */ 46 __P((void)); 47 vm_pager_t (*pgo_alloc) /* Allocate pager. */ 48 __P((caddr_t, vm_size_t, vm_prot_t, vm_offset_t)); 49 void (*pgo_dealloc) /* Disassociate. */ 50 __P((vm_pager_t)); 51 int (*pgo_getpages) /* Get (read) page. */ 52 __P((vm_pager_t, vm_page_t *, int, boolean_t)); 53 int (*pgo_putpages) /* Put (write) page. */ 54 __P((vm_pager_t, vm_page_t *, int, boolean_t)); 55 boolean_t (*pgo_haspage) /* Does pager have page? */ 56 __P((vm_pager_t, vm_offset_t)); 57 void (*pgo_cluster) /* Return range of cluster. */ 58 __P((vm_pager_t, vm_offset_t, 59 vm_offset_t *, vm_offset_t *)); 60 }; 61 62 /* 63 * get/put return values 64 * OK operation was successful 65 * BAD specified data was out of the accepted range 66 * FAIL specified data was in range, but doesn't exist 67 * PEND operations was initiated but not completed 68 * ERROR error while accessing data that is in range and exists 69 * AGAIN temporary resource shortage prevented operation from happening 70 */ 71 #define VM_PAGER_OK 0 72 #define VM_PAGER_BAD 1 73 #define VM_PAGER_FAIL 2 74 #define VM_PAGER_PEND 3 75 #define VM_PAGER_ERROR 4 76 #define VM_PAGER_AGAIN 5 77 78 #ifdef KERNEL 79 extern struct pagerops *dfltpagerops; 80 81 vm_pager_t vm_pager_allocate 82 __P((int, caddr_t, vm_size_t, vm_prot_t, vm_offset_t)); 83 vm_page_t vm_pager_atop __P((vm_offset_t)); 84 void vm_pager_cluster 85 __P((vm_pager_t, vm_offset_t, 86 vm_offset_t *, vm_offset_t *)); 87 void vm_pager_clusternull 88 __P((vm_pager_t, vm_offset_t, 89 vm_offset_t *, vm_offset_t *)); 90 void vm_pager_deallocate __P((vm_pager_t)); 91 int vm_pager_get_pages 92 __P((vm_pager_t, vm_page_t *, int, boolean_t)); 93 boolean_t vm_pager_has_page __P((vm_pager_t, vm_offset_t)); 94 void vm_pager_init __P((void)); 95 vm_pager_t vm_pager_lookup __P((struct pagerlst *, caddr_t)); 96 vm_offset_t vm_pager_map_pages __P((vm_page_t *, int, boolean_t)); 97 int vm_pager_put_pages 98 __P((vm_pager_t, vm_page_t *, int, boolean_t)); 99 void vm_pager_sync __P((void)); 100 void vm_pager_unmap_pages __P((vm_offset_t, int)); 101 102 #define vm_pager_cancluster(p, b) ((p)->pg_flags & (b)) 103 104 /* 105 * XXX compat with old interface 106 */ 107 int vm_pager_get __P((vm_pager_t, vm_page_t, boolean_t)); 108 int vm_pager_put __P((vm_pager_t, vm_page_t, boolean_t)); 109 #endif 110 111 #endif /* _VM_PAGER_ */ 112