Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 | /* * Copyright IBM Corp. 2008 * * Guest page hinting for unused pages. * * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com> */ #include <linux/kernel.h> #include <linux/errno.h> #include <linux/types.h> #include <linux/mm.h> #include <linux/gfp.h> #include <linux/init.h> #include <asm/setup.h> #include <asm/ipl.h> #define ESSA_SET_STABLE 1 #define ESSA_SET_UNUSED 2 static int cmma_flag = 1; static int __init cmma(char *str) { char *parm; parm = strstrip(str); if (strcmp(parm, "yes") == 0 || strcmp(parm, "on") == 0) { cmma_flag = 1; return 1; } cmma_flag = 0; if (strcmp(parm, "no") == 0 || strcmp(parm, "off") == 0) return 1; return 0; } __setup("cmma=", cmma); void __init cmma_init(void) { register unsigned long tmp asm("0") = 0; register int rc asm("1") = -EOPNOTSUPP; if (!cmma_flag) return; /* * Disable CMM for dump, otherwise the tprot based memory * detection can fail because of unstable pages. */ if (OLDMEM_BASE || ipl_info.type == IPL_TYPE_FCP_DUMP) { cmma_flag = 0; return; } asm volatile( " .insn rrf,0xb9ab0000,%1,%1,0,0\n" "0: la %0,0\n" "1:\n" EX_TABLE(0b,1b) : "+&d" (rc), "+&d" (tmp)); if (rc) cmma_flag = 0; } static inline void set_page_unstable(struct page *page, int order) { int i, rc; for (i = 0; i < (1 << order); i++) asm volatile(".insn rrf,0xb9ab0000,%0,%1,%2,0" : "=&d" (rc) : "a" (page_to_phys(page + i)), "i" (ESSA_SET_UNUSED)); } void arch_free_page(struct page *page, int order) { if (!cmma_flag) return; set_page_unstable(page, order); } static inline void set_page_stable(struct page *page, int order) { int i, rc; for (i = 0; i < (1 << order); i++) asm volatile(".insn rrf,0xb9ab0000,%0,%1,%2,0" : "=&d" (rc) : "a" (page_to_phys(page + i)), "i" (ESSA_SET_STABLE)); } void arch_alloc_page(struct page *page, int order) { if (!cmma_flag) return; set_page_stable(page, order); } void arch_set_page_states(int make_stable) { unsigned long flags, order, t; struct list_head *l; struct page *page; struct zone *zone; if (!cmma_flag) return; if (make_stable) drain_local_pages(NULL); for_each_populated_zone(zone) { spin_lock_irqsave(&zone->lock, flags); for_each_migratetype_order(order, t) { list_for_each(l, &zone->free_area[order].free_list[t]) { page = list_entry(l, struct page, lru); if (make_stable) set_page_stable(page, order); else set_page_unstable(page, order); } } spin_unlock_irqrestore(&zone->lock, flags); } } |