/*
* Mach Operating System
* Copyright (c) 1993-1989 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
#ifndef __MACH_DEFPAGER_PRIV_H__
#define __MACH_DEFPAGER_PRIV_H__
#include <mach.h>
#include <queue.h>
#include <hurd/ihash.h>
/*
* Bitmap allocation.
*/
typedef unsigned int bm_entry_t;
#define NB_BM 32
#define BM_MASK 0xffffffff
#define howmany(a,b) (((a) + (b) - 1)/(b))
/*
* Value to indicate no block assigned
*/
#define NO_BLOCK ((vm_offset_t)-1)
/*
* 'Partition' structure for each paging area.
* Controls allocation of blocks within paging area.
*/
struct part {
pthread_mutex_t p_lock; /* for bitmap/free */
vm_size_t total_size; /* total number of blocks */
vm_size_t free; /* number of blocks free */
unsigned int id; /* named lookup */
bm_entry_t *bitmap; /* allocation map */
boolean_t going_away; /* destroy attempt in progress */
struct file_direct *file; /* file paged to */
};
typedef struct part *partition_t;
struct {
pthread_mutex_t lock;
int n_partitions;
partition_t *partition_list;/* array, for quick mapping */
} all_partitions; /* list of all such */
typedef unsigned char p_index_t;
#define P_INDEX_INVALID ((p_index_t)-1)
#define no_partition(x) ((x) == P_INDEX_INVALID)
/*
* Allocation info for each paging object.
*
* Most operations, even pager_write_offset and pager_put_checksum,
* just need a read lock. Higher-level considerations prevent
* conflicting operations on a single page. The lock really protects
* the underlying size and block map memory, so pager_extend needs a
* write lock.
*
* An object can now span multiple paging partitions. The allocation
* info we keep is a pair (offset,p_index) where the index is in the
* array of all partition ptrs, and the offset is partition-relative.
* Size wise we are doing ok fitting the pair into a single integer:
* the offset really is in pages so we have vm_page_size bits available
* for the partition index.
*/
#define DEBUG_READER_CONFLICTS 0
#if DEBUG_READER_CONFLICTS
int default_pager_read_conflicts = 0;
#endif
union dp_map {
struct {
unsigned int p_offset : 24,
p_index : 8;
} block;
union dp_map *indirect;
};
typedef union dp_map *dp_map_t;
/* quick check for part==block==invalid */
#define no_block(e) ((e).indirect == (dp_map_t)NO_BLOCK)
#define invalidate_block(e) ((e).indirect = (dp_map_t)NO_BLOCK)
struct dpager {
pthread_mutex_t lock; /* lock for extending block map */
/* XXX should be read-write lock */
#if DEBUG_READER_CONFLICTS
int readers;
boolean_t writer;
#endif
dp_map_t map; /* block map */
vm_size_t size; /* size of paging object, in pages */
vm_size_t limit; /* limit (bytes) allowed to grow to */
vm_size_t byte_limit; /* limit, which wasn't
rounded to page boundary */
p_index_t cur_partition;
#ifdef CHECKSUM
vm_offset_t *checksum; /* checksum - parallel to block map */
#define NO_CHECKSUM ((vm_offset_t)-1)
#endif /* CHECKSUM */
};
typedef struct dpager *dpager_t;
/*
* A paging object uses either a one- or a two-level map of offsets
* into a paging partition.
*/
#define PAGEMAP_ENTRIES 64
/* number of pages in a second-level map */
#define PAGEMAP_SIZE(npgs) ((npgs)*sizeof(vm_offset_t))
#define INDIRECT_PAGEMAP_ENTRIES(npgs) \
((((npgs)-1)/PAGEMAP_ENTRIES) + 1)
#define INDIRECT_PAGEMAP_SIZE(npgs) \
(INDIRECT_PAGEMAP_ENTRIES(npgs) * sizeof(vm_offset_t *))
#define INDIRECT_PAGEMAP(size) \
(size > PAGEMAP_ENTRIES)
#define ROUNDUP_TO_PAGEMAP(npgs) \
(((npgs) + PAGEMAP_ENTRIES - 1) & ~(PAGEMAP_ENTRIES - 1))
/*
* Mapping between pager port and paging object.
*/
struct dstruct {
hurd_ihash_locp_t htable_locp; /* for the ihash table */
queue_chain_t links; /* Link in pager-port list */
pthread_mutex_t lock; /* Lock for the structure */
pthread_cond_t
waiting_seqno, /* someone waiting on seqno */
waiting_read, /* someone waiting on readers */
waiting_write, /* someone waiting on writers */
waiting_refs; /* someone waiting on refs */
memory_object_t pager; /* Pager port */
mach_port_seqno_t seqno; /* Pager port sequence number */
mach_port_t pager_request; /* Request port */
mach_port_urefs_t request_refs; /* Request port user-refs */
mach_port_t pager_name; /* Name port */
mach_port_urefs_t name_refs; /* Name port user-refs */
boolean_t external; /* Is an external object? */
unsigned int readers; /* Reads in progress */
unsigned int writers; /* Writes in progress */
/* This is the reply port of an outstanding
default_pager_object_set_size call. */
mach_port_t lock_request;
unsigned int errors; /* Pageout error count */
struct dpager dpager; /* Actual pager */
};
typedef struct dstruct * default_pager_t;
#define DEFAULT_PAGER_NULL ((default_pager_t)0)
/*
* List of all pagers. A specific pager is
* found directly via its port, this list is
* only used for monitoring purposes by the
* default_pager_object* calls
*/
struct pager_port {
struct hurd_ihash htable;
pthread_mutex_t lock;
queue_head_t leak_queue;
};
/* The list of pagers. */
extern struct pager_port all_pagers;
#endif /* __MACH_DEFPAGER_PRIV_H__ */