1 /* $OpenBSD: uvm_pmemrange.h,v 1.11 2011/07/08 18:25:56 ariane Exp $ */ 2 3 /* 4 * Copyright (c) 2009 Ariane van der Steldt <ariane@stack.nl> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 /* 20 * uvm_pmemrange.h: describe and manage free physical memory. 21 */ 22 23 #ifndef _UVM_UVM_PMEMRANGE_H_ 24 #define _UVM_UVM_PMEMRANGE_H_ 25 26 #include <uvm/uvm_extern.h> 27 #include <uvm/uvm_page.h> 28 29 RB_HEAD(uvm_pmr_addr, vm_page); 30 RB_HEAD(uvm_pmr_size, vm_page); 31 32 /* 33 * Page types available: 34 * - DIRTY: this page may contain random data. 35 * - ZERO: this page has been zeroed. 36 */ 37 #define UVM_PMR_MEMTYPE_DIRTY 0 38 #define UVM_PMR_MEMTYPE_ZERO 1 39 #define UVM_PMR_MEMTYPE_MAX 2 40 41 /* 42 * An address range of memory. 43 */ 44 struct uvm_pmemrange { 45 struct uvm_pmr_addr addr; /* Free page chunks, sorted by addr. */ 46 struct uvm_pmr_size size[UVM_PMR_MEMTYPE_MAX]; 47 /* Free page chunks, sorted by size. */ 48 TAILQ_HEAD(, vm_page) single[UVM_PMR_MEMTYPE_MAX]; 49 /* single page regions (uses pageq) */ 50 51 paddr_t low; /* Start of address range (pgno). */ 52 paddr_t high; /* End +1 (pgno). */ 53 int use; /* Use counter. */ 54 psize_t nsegs; /* Current range count. */ 55 56 TAILQ_ENTRY(uvm_pmemrange) pmr_use; 57 /* pmr, sorted by use */ 58 RB_ENTRY(uvm_pmemrange) pmr_addr; 59 /* pmr, sorted by address */ 60 }; 61 62 /* 63 * Description of failing memory allocation. 64 * 65 * Two ways new pages can become available: 66 * [1] page daemon drops them (we notice because they are freed) 67 * [2] a process calls free 68 * 69 * The buffer cache and page daemon can decide that they don't have the 70 * ability to make pages available in the requested range. In that case, 71 * the FAIL bit will be set. 72 * XXX There's a possibility that a page is no longer on the queues but 73 * XXX has not yet been freed, or that a page was busy. 74 * XXX Also, wired pages are not considered for paging, so they could 75 * XXX cause a failure that may be recoverable. 76 */ 77 struct uvm_pmalloc { 78 TAILQ_ENTRY(uvm_pmalloc) pmq; 79 80 /* 81 * Allocation request parameters. 82 */ 83 struct uvm_constraint_range pm_constraint; 84 psize_t pm_size; 85 86 /* 87 * State flags. 88 */ 89 int pm_flags; 90 }; 91 92 /* 93 * uvm_pmalloc flags. 94 */ 95 #define UVM_PMA_LINKED 0x01 /* uvm_pmalloc is on list */ 96 #define UVM_PMA_BUSY 0x02 /* entry is busy with fpageq unlocked */ 97 #define UVM_PMA_FAIL 0x10 /* page daemon cannot free pages */ 98 #define UVM_PMA_FREED 0x20 /* at least one page in the range was freed */ 99 100 RB_HEAD(uvm_pmemrange_addr, uvm_pmemrange); 101 TAILQ_HEAD(uvm_pmemrange_use, uvm_pmemrange); 102 103 /* 104 * pmr control structure. Contained in uvm.pmr_control. 105 */ 106 struct uvm_pmr_control { 107 struct uvm_pmemrange_addr addr; 108 struct uvm_pmemrange_use use; 109 110 /* Only changed while fpageq is locked. */ 111 TAILQ_HEAD(, uvm_pmalloc) allocs; 112 }; 113 114 void uvm_pmr_freepages(struct vm_page *, psize_t); 115 void uvm_pmr_freepageq(struct pglist *); 116 int uvm_pmr_getpages(psize_t, paddr_t, paddr_t, paddr_t, paddr_t, 117 int, int, struct pglist *); 118 void uvm_pmr_init(void); 119 int uvm_wait_pla(paddr_t, paddr_t, paddr_t, int); 120 void uvm_wakeup_pla(paddr_t, psize_t); 121 122 #if defined(DDB) || defined(DEBUG) 123 int uvm_pmr_isfree(struct vm_page *pg); 124 #endif 125 126 /* 127 * Internal tree logic. 128 */ 129 130 int uvm_pmr_addr_cmp(struct vm_page *, struct vm_page *); 131 int uvm_pmr_size_cmp(struct vm_page *, struct vm_page *); 132 133 RB_PROTOTYPE(uvm_pmr_addr, vm_page, objt, uvm_pmr_addr_cmp); 134 RB_PROTOTYPE(uvm_pmr_size, vm_page, objt, uvm_pmr_size_cmp); 135 RB_PROTOTYPE(uvm_pmemrange_addr, uvm_pmemrange, pmr_addr, 136 uvm_pmemrange_addr_cmp); 137 138 struct vm_page *uvm_pmr_insert_addr(struct uvm_pmemrange *, 139 struct vm_page *, int); 140 void uvm_pmr_insert_size(struct uvm_pmemrange *, 141 struct vm_page *); 142 struct vm_page *uvm_pmr_insert(struct uvm_pmemrange *, 143 struct vm_page *, int); 144 void uvm_pmr_remove_addr(struct uvm_pmemrange *, 145 struct vm_page *); 146 void uvm_pmr_remove_size(struct uvm_pmemrange *, 147 struct vm_page *); 148 void uvm_pmr_remove(struct uvm_pmemrange *, 149 struct vm_page *); 150 struct vm_page *uvm_pmr_extract_range(struct uvm_pmemrange *, 151 struct vm_page *, paddr_t, paddr_t, 152 struct pglist *); 153 154 #endif /* _UVM_UVM_PMEMRANGE_H_ */ 155