swap.h revision ba3594ba9b5dd4c846c472a8d657edcb7c8109ac
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2014 Garrett D'Amore <garrett@damore.org>
* Copyright (c) 1987, 2010, Oracle and/or its affiliates. All rights reserved.
*/
/* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* University Copyright- Copyright (c) 1982, 1986, 1988
* The Regents of the University of California
* All Rights Reserved
*
* University Acknowledgment- Portions of this document are derived from
* software developed by the University of California, Berkeley, and its
* contributors.
*/
#ifndef _SYS_SWAP_H
#define _SYS_SWAP_H
#include <sys/isa_defs.h>
#include <sys/feature_tests.h>
#include <vm/anon.h>
#include <sys/fs/swapnode.h>
#ifdef __cplusplus
extern "C" {
#endif
#if !defined(_LP64) && _FILE_OFFSET_BITS == 64
#error "Cannot use swapctl in the large files compilation environment"
#endif
/* The following are for the swapctl system call */
#define SC_ADD 1 /* add a specified resource for swapping */
#define SC_LIST 2 /* list all the swapping resources */
#define SC_REMOVE 3 /* remove the specified swapping resource */
#define SC_GETNSWP 4 /* get number of swap resources configured */
#define SC_AINFO 5 /* get anonymous memory resource information */
typedef struct swapres {
char *sr_name; /* pathname of the resource specified */
off_t sr_start; /* starting offset of the swapping resource */
off_t sr_length; /* length of the swap area */
} swapres_t;
typedef struct swapent {
char *ste_path; /* get the name of the swap file */
off_t ste_start; /* starting block for swapping */
off_t ste_length; /* length of swap area */
long ste_pages; /* numbers of pages for swapping */
long ste_free; /* numbers of ste_pages free */
int ste_flags; /* see below */
} swapent_t;
typedef struct swaptable {
int swt_n; /* number of swapents following */
struct swapent swt_ent[1]; /* array of swt_n swapents */
} swaptbl_t;
#if defined(_SYSCALL32)
/* Kernel's view of user ILP32 swapres and swapent structures */
typedef struct swapres32 {
caddr32_t sr_name; /* pathname of the resource specified */
off32_t sr_start; /* starting offset of the swapping resource */
off32_t sr_length; /* length of the swap area */
} swapres32_t;
typedef struct swapent32 {
caddr32_t ste_path; /* get the name of the swap file */
off32_t ste_start; /* starting block for swapping */
off32_t ste_length; /* length of swap area */
int32_t ste_pages; /* numbers of pages for swapping */
int32_t ste_free; /* numbers of ste_pages free */
int32_t ste_flags; /* see below */
} swapent32_t;
typedef struct swaptable32 {
int32_t swt_n; /* number of swapents following */
struct swapent32 swt_ent[1]; /* array of swt_n swapents */
} swaptbl32_t;
#endif /* _SYSCALL32 */
#if defined(_KERNEL)
extern int swapctl(int, void *, int *);
#if defined(_LP64) && defined(_SYSCALL32)
extern int swapctl32(int, void *, int *);
#endif /* _LP64 && _SYSCALL32 */
#else /* !_KERNEL */
extern int swapctl(int, void *);
#endif /* _KERNEL */
/* ste_flags values */
#define ST_INDEL 0x01 /* Deletion of file is in progress. */
/* Prevents others from deleting or */
/* allocating from it */
#define ST_DOINGDEL 0x02 /* Set during deletion of file */
/* Clearing during deletion signals */
/* that you want to add the file back */
/* again, and will eventually cause */
/* it to be added back */
/*
* VM - virtual swap device.
*/
struct swapinfo {
ulong_t si_soff; /* starting offset (bytes) of file */
ulong_t si_eoff; /* ending offset (bytes) of file */
struct vnode *si_vp; /* vnode (commonvp if device) */
struct swapinfo *si_next; /* next swap area */
int si_allocs; /* # of conseq. allocs from this area */
short si_flags; /* flags defined below */
pgcnt_t si_npgs; /* number of pages of swap space */
pgcnt_t si_nfpgs; /* number of free pages of swap space */
int si_pnamelen; /* swap file name length + 1 */
char *si_pname; /* swap file name */
ssize_t si_mapsize; /* # bytes allocated for bitmap */
uint_t *si_swapslots; /* bitmap of slots, unset == free */
pgcnt_t si_hint; /* first page to check if free */
ssize_t si_checkcnt; /* # of checks to find freeslot */
ssize_t si_alloccnt; /* used to find ave checks */
};
/*
* Stuff to convert an anon slot pointer to a page name.
* Because the address of the slot (ap) is a unique identifier, we
* use it to generate a unique (vp,off), as shown in the comment for
* swap_alloc().
*
* The off bits are shifted PAGESHIFT to directly form a page aligned
* offset; the vp index bits map 1-1 to a vnode.
*
*/
#define MAX_SWAP_VNODES_LOG2 11 /* log2(MAX_SWAP_VNODES) */
#define MAX_SWAP_VNODES (1U << MAX_SWAP_VNODES_LOG2) /* max # swap vnodes */
#define AN_VPMASK (MAX_SWAP_VNODES - 1) /* vp index mask */
#define AN_VPSHIFT MAX_SWAP_VNODES_LOG2
/*
* Convert from an anon slot to associated vnode and offset.
*/
#define swap_xlate(AP, VPP, OFFP) \
{ \
*(VPP) = (AP)->an_vp; \
*(OFFP) = (AP)->an_off; \
}
#define swap_xlate_nopanic swap_xlate
/*
* Get a vnode name for an anon slot.
* The vnum, offset are derived from anon struct address which is
* 16 bytes aligned. anon structs may be kmem_cache_alloc'd concurrently by
* multiple threads and come from a small range of addresses (same slab), in
* which case high order AP bits do not vary much, so choose vnum from low
* order bits which vary the most. Different threads will thus get different
* vnums and vnodes, which avoids vph_mutex_contention on the subsequent
* page_hashin().
*
* +-----------...-------------------+-----------------------+----+
* | swap offset | vnum |0000|
* +-----------...-------------------+-----------------------+----+
* 63 15 14 4 3 0
*/
#define swap_alloc(AP) \
{ \
(AP)->an_vp = swapfs_getvp(((uintptr_t)(AP) >> AN_CACHE_ALIGN_LOG2) \
& AN_VPMASK); \
(AP)->an_off = (anoff_t)((((uintptr_t)(AP)) >> \
AN_VPSHIFT + AN_CACHE_ALIGN_LOG2) << PAGESHIFT); \
}
/*
* Free the page name for the specified anon slot.
* For now there's nothing to do.
*/
#define swap_free(AP)
/* Flags for swap_phys_alloc */
#define SA_NOT 0x01 /* Must have slot from swap dev other than input one */
/* Special error codes for swap_newphysname() */
#define SE_NOSWAP -1 /* No physical swap slots available */
#define SE_NOANON -2 /* No anon slot for swap slot */
#ifdef _KERNEL
extern struct anon *swap_anon(struct vnode *vp, u_offset_t off);
extern int swap_phys_alloc(struct vnode **vpp, u_offset_t *offp, size_t *lenp,
uint_t flags);
extern void swap_phys_free(struct vnode *vp, u_offset_t off, size_t len);
extern int swap_getphysname(struct vnode *vp, u_offset_t off,
struct vnode **pvpp, u_offset_t *poffp);
extern int swap_newphysname(struct vnode *vp, u_offset_t offset,
u_offset_t *offp, size_t *lenp, struct vnode **pvpp, u_offset_t *poffp);
extern struct swapinfo *swapinfo;
extern int swap_debug;
#endif /* _KERNEL */
#ifdef SWAP_DEBUG
#define SW_RENAME 0x01
#define SW_RESV 0x02
#define SW_ALLOC 0x04
#define SW_CTL 0x08
#define SWAP_PRINT(f, s, x1, x2, x3, x4, x5) \
if (swap_debug & f) \
printf(s, x1, x2, x3, x4, x5);
#else /* SWAP_DEBUG */
#define SWAP_PRINT(f, s, x1, x2, x3, x4, x5)
#endif /* SWAP_DEBUG */
#ifdef __cplusplus
}
#endif
#endif /* _SYS_SWAP_H */