diff options
Diffstat (limited to 'sys/uvm/uvm_page.c')
| -rw-r--r-- | sys/uvm/uvm_page.c | 187 |
1 files changed, 185 insertions, 2 deletions
diff --git a/sys/uvm/uvm_page.c b/sys/uvm/uvm_page.c index 08e8a5cb852..58b93ef499e 100644 --- a/sys/uvm/uvm_page.c +++ b/sys/uvm/uvm_page.c @@ -1,4 +1,4 @@ -/* $OpenBSD: uvm_page.c,v 1.69 2009/03/24 16:29:42 oga Exp $ */ +/* $OpenBSD: uvm_page.c,v 1.70 2009/03/25 20:00:18 oga Exp $ */ /* $NetBSD: uvm_page.c,v 1.44 2000/11/27 08:40:04 chs Exp $ */ /* @@ -71,7 +71,6 @@ * uvm_page.c: page ops. */ -#define UVM_PAGE /* pull in uvm_page.h functions */ #include <sys/param.h> #include <sys/systm.h> #include <sys/malloc.h> @@ -1495,3 +1494,187 @@ PHYS_TO_VM_PAGE(paddr_t pa) return ((psi == -1) ? NULL : &vm_physmem[psi].pgs[off]); } +/* + * uvm_pagelookup: look up a page + * + * => caller should lock object to keep someone from pulling the page + * out from under it + */ +struct vm_page * +uvm_pagelookup(struct uvm_object *obj, voff_t off) +{ + struct vm_page *pg; + struct pglist *buck; + int s; + + buck = &uvm.page_hash[uvm_pagehash(obj,off)]; + + s = splvm(); + simple_lock(&uvm.hashlock); + TAILQ_FOREACH(pg, buck, hashq) { + if (pg->uobject == obj && pg->offset == off) { + break; + } + } + simple_unlock(&uvm.hashlock); + splx(s); + return(pg); +} + +/* + * uvm_pagewire: wire the page, thus removing it from the daemon's grasp + * + * => caller must lock page queues + */ +void +uvm_pagewire(struct vm_page *pg) +{ + if (pg->wire_count == 0) { + if (pg->pg_flags & PQ_ACTIVE) { + TAILQ_REMOVE(&uvm.page_active, pg, pageq); + atomic_clearbits_int(&pg->pg_flags, PQ_ACTIVE); + uvmexp.active--; + } + if (pg->pg_flags & PQ_INACTIVE) { + if (pg->pg_flags & PQ_SWAPBACKED) + TAILQ_REMOVE(&uvm.page_inactive_swp, pg, pageq); + else + TAILQ_REMOVE(&uvm.page_inactive_obj, pg, pageq); + atomic_clearbits_int(&pg->pg_flags, PQ_INACTIVE); + uvmexp.inactive--; + } + uvmexp.wired++; + } + pg->wire_count++; +} + +/* + * uvm_pageunwire: unwire the page. + * + * => activate if wire count goes to zero. + * => caller must lock page queues + */ +void +uvm_pageunwire(struct vm_page *pg) +{ + pg->wire_count--; + if (pg->wire_count == 0) { + TAILQ_INSERT_TAIL(&uvm.page_active, pg, pageq); + uvmexp.active++; + atomic_setbits_int(&pg->pg_flags, PQ_ACTIVE); + uvmexp.wired--; + } +} + +/* + * uvm_pagedeactivate: deactivate page -- no pmaps have access to page + * + * => caller must lock page queues + * => caller must check to make sure page is not wired + * => object that page belongs to must be locked (so we can adjust pg->flags) + */ +void +uvm_pagedeactivate(struct vm_page *pg) +{ + if (pg->pg_flags & PQ_ACTIVE) { + TAILQ_REMOVE(&uvm.page_active, pg, pageq); + atomic_clearbits_int(&pg->pg_flags, PQ_ACTIVE); + uvmexp.active--; + } + if ((pg->pg_flags & PQ_INACTIVE) == 0) { + KASSERT(pg->wire_count == 0); + if (pg->pg_flags & PQ_SWAPBACKED) + TAILQ_INSERT_TAIL(&uvm.page_inactive_swp, pg, pageq); + else + TAILQ_INSERT_TAIL(&uvm.page_inactive_obj, pg, pageq); + atomic_setbits_int(&pg->pg_flags, PQ_INACTIVE); + uvmexp.inactive++; + pmap_clear_reference(pg); + /* + * update the "clean" bit. this isn't 100% + * accurate, and doesn't have to be. we'll + * re-sync it after we zap all mappings when + * scanning the inactive list. + */ + if ((pg->pg_flags & PG_CLEAN) != 0 && + pmap_is_modified(pg)) + atomic_clearbits_int(&pg->pg_flags, PG_CLEAN); + } +} + +/* + * uvm_pageactivate: activate page + * + * => caller must lock page queues + */ +void +uvm_pageactivate(struct vm_page *pg) +{ + if (pg->pg_flags & PQ_INACTIVE) { + if (pg->pg_flags & PQ_SWAPBACKED) + TAILQ_REMOVE(&uvm.page_inactive_swp, pg, pageq); + else + TAILQ_REMOVE(&uvm.page_inactive_obj, pg, pageq); + atomic_clearbits_int(&pg->pg_flags, PQ_INACTIVE); + uvmexp.inactive--; + } + if (pg->wire_count == 0) { + + /* + * if page is already active, remove it from list so we + * can put it at tail. if it wasn't active, then mark + * it active and bump active count + */ + if (pg->pg_flags & PQ_ACTIVE) + TAILQ_REMOVE(&uvm.page_active, pg, pageq); + else { + atomic_setbits_int(&pg->pg_flags, PQ_ACTIVE); + uvmexp.active++; + } + + TAILQ_INSERT_TAIL(&uvm.page_active, pg, pageq); + } +} + +/* + * uvm_pagezero: zero fill a page + * + * => if page is part of an object then the object should be locked + * to protect pg->flags. + */ +void +uvm_pagezero(struct vm_page *pg) +{ + atomic_clearbits_int(&pg->pg_flags, PG_CLEAN); + pmap_zero_page(pg); +} + +/* + * uvm_pagecopy: copy a page + * + * => if page is part of an object then the object should be locked + * to protect pg->flags. + */ +void +uvm_pagecopy(struct vm_page *src, struct vm_page *dst) +{ + atomic_clearbits_int(&dst->pg_flags, PG_CLEAN); + pmap_copy_page(src, dst); +} + +/* + * uvm_page_lookup_freelist: look up the free list for the specified page + */ +int +uvm_page_lookup_freelist(struct vm_page *pg) +{ +#if VM_PHYSSEG_MAX == 1 + return (vm_physmem[0].free_list); +#else + int lcv; + + lcv = vm_physseg_find(atop(VM_PAGE_TO_PHYS(pg)), NULL); + KASSERT(lcv != -1); + return (vm_physmem[lcv].free_list); +#endif +} |