BSD 4.4 Lite Kernel Sources

1 files changed, 147 insertions, 0 deletions

diff --git a/sys/vm/vm_pager.h b/sys/vm/vm_pager.h
new file mode 100644
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--- /dev/null
+++ b/sys/vm/vm_pager.h
@@ -0,0 +1,147 @@
+/*
+ * Copyright (c) 1990 University of Utah.
+ * Copyright (c) 1991, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * the Systems Programming Group of the University of Utah Computer
+ * Science Department.
+ *
+ * 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.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
+ *
+ *	@(#)vm_pager.h	8.4 (Berkeley) 1/12/94
+ */
+
+/*
+ * Pager routine interface definition.
+ * For BSD we use a cleaner version of the internal pager interface.
+ */
+
+#ifndef	_VM_PAGER_
+#define	_VM_PAGER_
+
+TAILQ_HEAD(pagerlst, pager_struct);
+
+struct	pager_struct {
+	TAILQ_ENTRY(pager_struct) pg_list;	/* links for list management */
+	caddr_t			  pg_handle;	/* ext. handle (vp, dev, fp) */
+	int			  pg_type;	/* type of pager */
+	int			  pg_flags;	/* flags */
+	struct pagerops		  *pg_ops;	/* pager operations */
+	void			  *pg_data;	/* private pager data */
+};
+
+/* pager types */
+#define PG_DFLT		-1
+#define	PG_SWAP		0
+#define	PG_VNODE	1
+#define PG_DEVICE	2
+
+/* flags */
+#define PG_CLUSTERGET	1
+#define PG_CLUSTERPUT	2
+
+struct	pagerops {
+	void		(*pgo_init)		/* Initialize pager. */
+			    __P((void));
+	vm_pager_t	(*pgo_alloc)		/* Allocate pager. */
+			    __P((caddr_t, vm_size_t, vm_prot_t, vm_offset_t));
+	void		(*pgo_dealloc)		/* Disassociate. */
+			    __P((vm_pager_t));
+	int		(*pgo_getpages)		/* Get (read) page. */
+			    __P((vm_pager_t, vm_page_t *, int, boolean_t));
+	int		(*pgo_putpages)		/* Put (write) page. */
+			    __P((vm_pager_t, vm_page_t *, int, boolean_t));
+	boolean_t  	(*pgo_haspage)		/* Does pager have page? */
+			    __P((vm_pager_t, vm_offset_t));
+	void		(*pgo_cluster)		/* Return range of cluster. */
+			    __P((vm_pager_t, vm_offset_t,
+				 vm_offset_t *, vm_offset_t *));
+};
+
+/*
+ * get/put return values
+ * OK	 operation was successful
+ * BAD	 specified data was out of the accepted range
+ * FAIL	 specified data was in range, but doesn't exist
+ * PEND	 operations was initiated but not completed
+ * ERROR error while accessing data that is in range and exists
+ * AGAIN temporary resource shortage prevented operation from happening
+ */
+#define	VM_PAGER_OK	0
+#define	VM_PAGER_BAD	1
+#define	VM_PAGER_FAIL	2
+#define	VM_PAGER_PEND	3
+#define	VM_PAGER_ERROR	4
+#define VM_PAGER_AGAIN	5
+
+#ifdef KERNEL
+extern struct pagerops *dfltpagerops;
+
+vm_pager_t	 vm_pager_allocate
+		    __P((int, caddr_t, vm_size_t, vm_prot_t, vm_offset_t));
+vm_page_t	 vm_pager_atop __P((vm_offset_t));
+void		 vm_pager_cluster
+		    __P((vm_pager_t, vm_offset_t,
+			 vm_offset_t *, vm_offset_t *));
+void		 vm_pager_clusternull
+		    __P((vm_pager_t, vm_offset_t,
+			 vm_offset_t *, vm_offset_t *));
+void		 vm_pager_deallocate __P((vm_pager_t));
+int		 vm_pager_get_pages
+		    __P((vm_pager_t, vm_page_t *, int, boolean_t));
+boolean_t	 vm_pager_has_page __P((vm_pager_t, vm_offset_t));
+void		 vm_pager_init __P((void));
+vm_pager_t	 vm_pager_lookup __P((struct pagerlst *, caddr_t));
+vm_offset_t	 vm_pager_map_pages __P((vm_page_t *, int, boolean_t));
+int		 vm_pager_put_pages
+		    __P((vm_pager_t, vm_page_t *, int, boolean_t));
+void		 vm_pager_sync __P((void));
+void		 vm_pager_unmap_pages __P((vm_offset_t, int));
+
+#define vm_pager_cancluster(p, b)	((p)->pg_flags & (b))
+
+/*
+ * XXX compat with old interface
+ */
+#define vm_pager_get(p, m, s) \
+({ \
+	vm_page_t ml[1]; \
+	ml[0] = (m); \
+	vm_pager_get_pages(p, ml, 1, s); \
+})
+#define vm_pager_put(p, m, s) \
+({ \
+	vm_page_t ml[1]; \
+	ml[0] = (m); \
+	vm_pager_put_pages(p, ml, 1, s); \
+})
+#endif
+
+#endif	/* _VM_PAGER_ */