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/* $OpenBSD: uvm_pmemrange.h,v 1.12 2015/02/05 23:51:06 mpi Exp $ */
/*
* Copyright (c) 2009 Ariane van der Steldt <ariane@stack.nl>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/*
* uvm_pmemrange.h: describe and manage free physical memory.
*/
#ifndef _UVM_UVM_PMEMRANGE_H_
#define _UVM_UVM_PMEMRANGE_H_
RB_HEAD(uvm_pmr_addr, vm_page);
RB_HEAD(uvm_pmr_size, vm_page);
/*
* Page types available:
* - DIRTY: this page may contain random data.
* - ZERO: this page has been zeroed.
*/
#define UVM_PMR_MEMTYPE_DIRTY 0
#define UVM_PMR_MEMTYPE_ZERO 1
#define UVM_PMR_MEMTYPE_MAX 2
/*
* An address range of memory.
*/
struct uvm_pmemrange {
struct uvm_pmr_addr addr; /* Free page chunks, sorted by addr. */
struct uvm_pmr_size size[UVM_PMR_MEMTYPE_MAX];
/* Free page chunks, sorted by size. */
TAILQ_HEAD(, vm_page) single[UVM_PMR_MEMTYPE_MAX];
/* single page regions (uses pageq) */
paddr_t low; /* Start of address range (pgno). */
paddr_t high; /* End +1 (pgno). */
int use; /* Use counter. */
psize_t nsegs; /* Current range count. */
TAILQ_ENTRY(uvm_pmemrange) pmr_use;
/* pmr, sorted by use */
RB_ENTRY(uvm_pmemrange) pmr_addr;
/* pmr, sorted by address */
};
/*
* Description of failing memory allocation.
*
* Two ways new pages can become available:
* [1] page daemon drops them (we notice because they are freed)
* [2] a process calls free
*
* The buffer cache and page daemon can decide that they don't have the
* ability to make pages available in the requested range. In that case,
* the FAIL bit will be set.
* XXX There's a possibility that a page is no longer on the queues but
* XXX has not yet been freed, or that a page was busy.
* XXX Also, wired pages are not considered for paging, so they could
* XXX cause a failure that may be recoverable.
*/
struct uvm_pmalloc {
TAILQ_ENTRY(uvm_pmalloc) pmq;
/*
* Allocation request parameters.
*/
struct uvm_constraint_range pm_constraint;
psize_t pm_size;
/*
* State flags.
*/
int pm_flags;
};
/*
* uvm_pmalloc flags.
*/
#define UVM_PMA_LINKED 0x01 /* uvm_pmalloc is on list */
#define UVM_PMA_BUSY 0x02 /* entry is busy with fpageq unlocked */
#define UVM_PMA_FAIL 0x10 /* page daemon cannot free pages */
#define UVM_PMA_FREED 0x20 /* at least one page in the range was freed */
RB_HEAD(uvm_pmemrange_addr, uvm_pmemrange);
TAILQ_HEAD(uvm_pmemrange_use, uvm_pmemrange);
/*
* pmr control structure. Contained in uvm.pmr_control.
*/
struct uvm_pmr_control {
struct uvm_pmemrange_addr addr;
struct uvm_pmemrange_use use;
/* Only changed while fpageq is locked. */
TAILQ_HEAD(, uvm_pmalloc) allocs;
};
void uvm_pmr_freepages(struct vm_page *, psize_t);
void uvm_pmr_freepageq(struct pglist *);
int uvm_pmr_getpages(psize_t, paddr_t, paddr_t, paddr_t, paddr_t,
int, int, struct pglist *);
void uvm_pmr_init(void);
int uvm_wait_pla(paddr_t, paddr_t, paddr_t, int);
void uvm_wakeup_pla(paddr_t, psize_t);
#if defined(DDB) || defined(DEBUG)
int uvm_pmr_isfree(struct vm_page *pg);
#endif
/*
* Internal tree logic.
*/
int uvm_pmr_addr_cmp(struct vm_page *, struct vm_page *);
int uvm_pmr_size_cmp(struct vm_page *, struct vm_page *);
RB_PROTOTYPE(uvm_pmr_addr, vm_page, objt, uvm_pmr_addr_cmp);
RB_PROTOTYPE(uvm_pmr_size, vm_page, objt, uvm_pmr_size_cmp);
RB_PROTOTYPE(uvm_pmemrange_addr, uvm_pmemrange, pmr_addr,
uvm_pmemrange_addr_cmp);
struct vm_page *uvm_pmr_insert_addr(struct uvm_pmemrange *,
struct vm_page *, int);
void uvm_pmr_insert_size(struct uvm_pmemrange *,
struct vm_page *);
struct vm_page *uvm_pmr_insert(struct uvm_pmemrange *,
struct vm_page *, int);
void uvm_pmr_remove_addr(struct uvm_pmemrange *,
struct vm_page *);
void uvm_pmr_remove_size(struct uvm_pmemrange *,
struct vm_page *);
void uvm_pmr_remove(struct uvm_pmemrange *,
struct vm_page *);
struct vm_page *uvm_pmr_extract_range(struct uvm_pmemrange *,
struct vm_page *, paddr_t, paddr_t,
struct pglist *);
#endif /* _UVM_UVM_PMEMRANGE_H_ */
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