1 /* $OpenBSD: uvm_pmemrange.h,v 1.14 2016/09/16 02:47:09 dlg 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 RBT_HEAD(uvm_pmr_addr, vm_page); 27 RBT_HEAD(uvm_pmr_size, vm_page); 28 29 /* 30 * Page types available: 31 * - DIRTY: this page may contain random data. 32 * - ZERO: this page has been zeroed. 33 */ 34 #define UVM_PMR_MEMTYPE_DIRTY 0 35 #define UVM_PMR_MEMTYPE_ZERO 1 36 #define UVM_PMR_MEMTYPE_MAX 2 37 38 /* 39 * An address range of memory. 40 */ 41 struct uvm_pmemrange { 42 struct uvm_pmr_addr addr; /* Free page chunks, sorted by addr. */ 43 struct uvm_pmr_size size[UVM_PMR_MEMTYPE_MAX]; 44 /* Free page chunks, sorted by size. */ 45 TAILQ_HEAD(, vm_page) single[UVM_PMR_MEMTYPE_MAX]; 46 /* single page regions (uses pageq) */ 47 48 paddr_t low; /* Start of address range (pgno). */ 49 paddr_t high; /* End +1 (pgno). */ 50 int use; /* Use counter. */ 51 psize_t nsegs; /* Current range count. */ 52 53 TAILQ_ENTRY(uvm_pmemrange) pmr_use; 54 /* pmr, sorted by use */ 55 RBT_ENTRY(uvm_pmemrange) pmr_addr; 56 /* pmr, sorted by address */ 57 }; 58 59 /* 60 * Description of failing memory allocation. 61 * 62 * Two ways new pages can become available: 63 * [1] page daemon drops them (we notice because they are freed) 64 * [2] a process calls free 65 * 66 * The buffer cache and page daemon can decide that they don't have the 67 * ability to make pages available in the requested range. In that case, 68 * the FAIL bit will be set. 69 * XXX There's a possibility that a page is no longer on the queues but 70 * XXX has not yet been freed, or that a page was busy. 71 * XXX Also, wired pages are not considered for paging, so they could 72 * XXX cause a failure that may be recoverable. 73 */ 74 struct uvm_pmalloc { 75 TAILQ_ENTRY(uvm_pmalloc) pmq; 76 77 /* 78 * Allocation request parameters. 79 */ 80 struct uvm_constraint_range pm_constraint; 81 psize_t pm_size; 82 83 /* 84 * State flags. 85 */ 86 int pm_flags; 87 }; 88 89 /* 90 * uvm_pmalloc flags. 91 */ 92 #define UVM_PMA_LINKED 0x01 /* uvm_pmalloc is on list */ 93 #define UVM_PMA_BUSY 0x02 /* entry is busy with fpageq unlocked */ 94 #define UVM_PMA_FAIL 0x10 /* page daemon cannot free pages */ 95 #define UVM_PMA_FREED 0x20 /* at least one page in the range was freed */ 96 97 RBT_HEAD(uvm_pmemrange_addr, uvm_pmemrange); 98 TAILQ_HEAD(uvm_pmemrange_use, uvm_pmemrange); 99 100 /* 101 * pmr control structure. Contained in uvm.pmr_control. 102 */ 103 struct uvm_pmr_control { 104 struct uvm_pmemrange_addr addr; 105 struct uvm_pmemrange_use use; 106 107 /* Only changed while fpageq is locked. */ 108 TAILQ_HEAD(, uvm_pmalloc) allocs; 109 }; 110 111 void uvm_pmr_freepages(struct vm_page *, psize_t); 112 void uvm_pmr_freepageq(struct pglist *); 113 int uvm_pmr_getpages(psize_t, paddr_t, paddr_t, paddr_t, paddr_t, 114 int, int, struct pglist *); 115 void uvm_pmr_init(void); 116 int uvm_wait_pla(paddr_t, paddr_t, paddr_t, int); 117 void uvm_wakeup_pla(paddr_t, psize_t); 118 119 #if defined(DDB) || defined(DEBUG) 120 int uvm_pmr_isfree(struct vm_page *pg); 121 #endif 122 123 /* 124 * Internal tree logic. 125 */ 126 127 int uvm_pmr_addr_cmp(const struct vm_page *, const struct vm_page *); 128 int uvm_pmr_size_cmp(const struct vm_page *, const struct vm_page *); 129 130 RBT_PROTOTYPE(uvm_pmr_addr, vm_page, objt, uvm_pmr_addr_cmp); 131 RBT_PROTOTYPE(uvm_pmr_size, vm_page, objt, uvm_pmr_size_cmp); 132 RBT_PROTOTYPE(uvm_pmemrange_addr, uvm_pmemrange, pmr_addr, 133 uvm_pmemrange_addr_cmp); 134 135 struct vm_page *uvm_pmr_insert_addr(struct uvm_pmemrange *, 136 struct vm_page *, int); 137 void uvm_pmr_insert_size(struct uvm_pmemrange *, 138 struct vm_page *); 139 struct vm_page *uvm_pmr_insert(struct uvm_pmemrange *, 140 struct vm_page *, int); 141 void uvm_pmr_remove_addr(struct uvm_pmemrange *, 142 struct vm_page *); 143 void uvm_pmr_remove_size(struct uvm_pmemrange *, 144 struct vm_page *); 145 void uvm_pmr_remove(struct uvm_pmemrange *, 146 struct vm_page *); 147 struct vm_page *uvm_pmr_extract_range(struct uvm_pmemrange *, 148 struct vm_page *, paddr_t, paddr_t, 149 struct pglist *); 150 151 #endif /* _UVM_UVM_PMEMRANGE_H_ */ 152