seg_vn.h revision 6725680357ffd955fcc03d519e70de4c93ee9d61
/*
* 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 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1984, 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 _VM_SEG_VN_H
#define _VM_SEG_VN_H
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sys/lgrp.h>
#include <vm/anon.h>
#ifdef __cplusplus
extern "C" {
#endif
/*
* A pointer to this structure is passed to segvn_create().
*/
typedef struct segvn_crargs {
struct vnode *vp; /* vnode mapped from */
struct cred *cred; /* credentials */
u_offset_t offset; /* starting offset of vnode for mapping */
uchar_t type; /* type of sharing done */
uchar_t prot; /* protections */
uchar_t maxprot; /* maximum protections */
uint_t flags; /* flags */
struct anon_map *amp; /* anon mapping to map to */
uint_t szc; /* max preferred page size code */
uint_t lgrp_mem_policy_flags;
} segvn_crargs_t;
/*
* (Semi) private data maintained by the seg_vn driver per segment mapping.
*
* The read/write segment lock protects all of segvn_data including the
* vpage array. All fields in segvn_data are treated as read-only when
* the "read" version of the address space and the segment locks are held.
* The "write" version of the segment lock, however, is required in order to
* update the following fields:
*
* pageprot
* prot
* amp
* vpage
*
* softlockcnt
* is written by acquiring either the readers lock on the segment and
* freemem lock, or any lock combination which guarantees exclusive use
* of this segment (e.g., adress space writers lock,
* address space readers lock + segment writers lock).
*/
typedef struct segvn_data {
krwlock_t lock; /* protect segvn_data and vpage array */
kmutex_t segp_slock; /* serialize insertions into seg_pcache */
uchar_t pageprot; /* true if per page protections present */
uchar_t prot; /* current segment prot if pageprot == 0 */
uchar_t maxprot; /* maximum segment protections */
uchar_t type; /* type of sharing done */
u_offset_t offset; /* starting offset of vnode for mapping */
struct vnode *vp; /* vnode that segment mapping is to */
ulong_t anon_index; /* starting index into anon_map anon array */
struct anon_map *amp; /* pointer to anon share structure, if needed */
struct vpage *vpage; /* per-page information, if needed */
struct cred *cred; /* mapping credentials */
size_t swresv; /* swap space reserved for this segment */
uchar_t advice; /* madvise flags for segment */
uchar_t pageadvice; /* true if per page advice set */
ushort_t flags; /* flags - from sys/mman.h */
ssize_t softlockcnt; /* # of pages SOFTLOCKED in seg */
lgrp_mem_policy_info_t policy_info; /* memory allocation policy */
hat_region_cookie_t rcookie; /* region for hat calls */
lgrp_mem_policy_info_t tr_policy_info; /* memory allocation for TR */
struct seg *seg; /* pointer back to seg */
struct segvn_data *svn_trnext; /* textrepl list next link */
struct segvn_data *svn_trprev; /* textrepl list prev link */
int tr_state; /* TR (text replication) state */
uchar_t pageswap; /* true if per page swap accounting is set */
} segvn_data_t;
#ifdef _KERNEL
/*
* segment text replication states.
*/
#define SEGVN_TR_INIT (0) /* Check if text replication can be enabled */
#define SEGVN_TR_ON (1) /* Text replication is enabled */
#define SEGVN_TR_OFF (2) /* Text replication is disabled */
/*
* Macros for segvn segment driver locking.
*/
#define SEGVN_LOCK_ENTER(as, lock, type) rw_enter((lock), (type))
#define SEGVN_LOCK_EXIT(as, lock) rw_exit((lock))
#define SEGVN_LOCK_DOWNGRADE(as, lock) rw_downgrade((lock))
#define SEGVN_LOCK_TRYENTER(as, lock, type) rw_tryenter((lock), (type))
/*
* Macros to test lock states.
*/
#define SEGVN_LOCK_HELD(as, lock) RW_LOCK_HELD((lock))
#define SEGVN_READ_HELD(as, lock) RW_READ_HELD((lock))
#define SEGVN_WRITE_HELD(as, lock) RW_WRITE_HELD((lock))
/*
* Macro used to detect the need to Break the sharing of COW pages
*
* The rw == S_WRITE is for the COW case
* rw == S_READ and type == SOFTLOCK is for the physio case
* We don't want to share a softlocked page because it can cause problems
* with multithreaded apps but if rw == S_READ_NOCOW it's ok to not break
* sharing of COW pages even in SOFTLOCK case.
*/
#define BREAK_COW_SHARE(rw, type, seg_type) ((rw == S_WRITE || \
(type == F_SOFTLOCK && rw != S_READ_NOCOW)) && \
seg_type == MAP_PRIVATE)
#define SEGVN_ZFOD_ARGS(prot, max) \
{ NULL, NULL, 0, MAP_PRIVATE, prot, max, 0, NULL, 0, 0 }
#define AS_MAP_CHECK_VNODE_LPOOB(crfp, argsp) \
((crfp) == (int (*)())segvn_create && \
(((struct segvn_crargs *)(argsp))->flags & \
(MAP_TEXT | MAP_INITDATA)) && \
((struct segvn_crargs *)(argsp))->szc == 0 && \
((struct segvn_crargs *)(argsp))->vp != NULL)
#define AS_MAP_CHECK_ANON_LPOOB(crfp, argsp) \
((crfp) == (int (*)())segvn_create && \
(((struct segvn_crargs *)(argsp))->szc == 0 || \
((struct segvn_crargs *)(argsp))->szc == AS_MAP_HEAP || \
((struct segvn_crargs *)(argsp))->szc == AS_MAP_STACK) && \
((struct segvn_crargs *)(argsp))->vp == NULL)
#define SVNTR_HASH_FUNC(vp) (((((uintptr_t)(vp)) >> 4) ^ \
(((uintptr_t)(vp)) >> 11)) & \
(svntr_hashtab_sz - 1))
#define SEGVN_TR_ADDSTAT(stat) \
segvn_textrepl_stats[CPU->cpu_id].tr_stat_##stat++
/*
* A hash table entry looked up by vnode, off/eoff and szc to find anon map to
* use for text replication based on main thread's (t_tid = 1) lgrp.
*/
typedef struct svntr {
struct vnode *tr_vp; /* text file vnode */
u_offset_t tr_off; /* tr_vp mapping start offset */
size_t tr_eoff; /* tr_vp mapping end offset */
uint_t tr_szc; /* tr_vp mapping pagesize */
int tr_valid; /* entry validity state */
struct svntr *tr_next; /* next svntr in this hash bucket */
timestruc_t tr_mtime; /* tr_vp modification time */
timestruc_t tr_ctime; /* time of last change to attributes */
ulong_t tr_refcnt; /* number of segs sharing this entry */
segvn_data_t *tr_svnhead; /* list of segs sharing this entry */
struct anon_map *tr_amp[NLGRPS_MAX]; /* per lgrp anon maps */
} svntr_t;
typedef struct svntr_bucket {
svntr_t *tr_head; /* first svntr in this hash bucket */
kmutex_t tr_lock; /* per bucket lock */
} svntr_bucket_t;
typedef struct svntr_stats {
ulong_t tr_stat_gaerr; /* VOP_GETATTR() failures */
ulong_t tr_stat_overmap; /* no TR due to beyond EOF mappings */
ulong_t tr_stat_wrcnt; /* no TR due to writtable mappings */
ulong_t tr_stat_stale; /* TR entry is stale */
ulong_t tr_stat_overlap; /* overlap with other mappings */
ulong_t tr_stat_nokmem; /* no TR due to kmem alloc failures */
ulong_t tr_stat_noanon; /* no TR due to no swap space */
ulong_t tr_stat_normem; /* no TR due to no repl memory */
ulong_t tr_stat_nolock; /* async TR failure due to locks */
ulong_t tr_stat_asyncrepl; /* number of async TRs */
ulong_t tr_stat_repl; /* number of sync TRs */
ulong_t tr_stat_newamp; /* number of new amp allocs for TR */
} svntr_stats_t;
extern void segvn_init(void);
extern int segvn_create(struct seg *, void *);
extern struct seg_ops segvn_ops;
/*
* Provided as shorthand for creating user zfod segments.
*/
extern caddr_t zfod_argsp;
extern caddr_t kzfod_argsp;
extern caddr_t stack_exec_argsp;
extern caddr_t stack_noexec_argsp;
#endif /* _KERNEL */
#ifdef __cplusplus
}
#endif
#endif /* _VM_SEG_VN_H */