1 /* 2 * Linux Guest Relocation (LGR) detection 3 * 4 * Copyright IBM Corp. 2012 5 * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com> 6 */ 7 8 #include <linux/module.h> 9 #include <linux/timer.h> 10 #include <linux/slab.h> 11 #include <asm/facility.h> 12 #include <asm/sysinfo.h> 13 #include <asm/ebcdic.h> 14 #include <asm/debug.h> 15 #include <asm/ipl.h> 16 17 #define LGR_TIMER_INTERVAL_SECS (30 * 60) 18 #define VM_LEVEL_MAX 2 /* Maximum is 8, but we only record two levels */ 19 20 /* 21 * LGR info: Contains stfle and stsi data 22 */ 23 struct lgr_info { 24 /* Bit field with facility information: 4 DWORDs are stored */ 25 u64 stfle_fac_list[4]; 26 /* Level of system (1 = CEC, 2 = LPAR, 3 = z/VM */ 27 u32 level; 28 /* Level 1: CEC info (stsi 1.1.1) */ 29 char manufacturer[16]; 30 char type[4]; 31 char sequence[16]; 32 char plant[4]; 33 char model[16]; 34 /* Level 2: LPAR info (stsi 2.2.2) */ 35 u16 lpar_number; 36 char name[8]; 37 /* Level 3: VM info (stsi 3.2.2) */ 38 u8 vm_count; 39 struct { 40 char name[8]; 41 char cpi[16]; 42 } vm[VM_LEVEL_MAX]; 43 } __packed __aligned(8); 44 45 /* 46 * LGR globals 47 */ 48 static char lgr_page[PAGE_SIZE] __aligned(PAGE_SIZE); 49 static struct lgr_info lgr_info_last; 50 static struct lgr_info lgr_info_cur; 51 static struct debug_info *lgr_dbf; 52 53 /* 54 * Return number of valid stsi levels 55 */ 56 static inline int stsi_0(void) 57 { 58 int rc = stsi(NULL, 0, 0, 0); 59 60 return rc == -ENOSYS ? rc : (((unsigned int) rc) >> 28); 61 } 62 63 /* 64 * Copy buffer and then convert it to ASCII 65 */ 66 static void cpascii(char *dst, char *src, int size) 67 { 68 memcpy(dst, src, size); 69 EBCASC(dst, size); 70 } 71 72 /* 73 * Fill LGR info with 1.1.1 stsi data 74 */ 75 static void lgr_stsi_1_1_1(struct lgr_info *lgr_info) 76 { 77 struct sysinfo_1_1_1 *si = (void *) lgr_page; 78 79 if (stsi(si, 1, 1, 1) == -ENOSYS) 80 return; 81 cpascii(lgr_info->manufacturer, si->manufacturer, 82 sizeof(si->manufacturer)); 83 cpascii(lgr_info->type, si->type, sizeof(si->type)); 84 cpascii(lgr_info->model, si->model, sizeof(si->model)); 85 cpascii(lgr_info->sequence, si->sequence, sizeof(si->sequence)); 86 cpascii(lgr_info->plant, si->plant, sizeof(si->plant)); 87 } 88 89 /* 90 * Fill LGR info with 2.2.2 stsi data 91 */ 92 static void lgr_stsi_2_2_2(struct lgr_info *lgr_info) 93 { 94 struct sysinfo_2_2_2 *si = (void *) lgr_page; 95 96 if (stsi(si, 2, 2, 2) == -ENOSYS) 97 return; 98 cpascii(lgr_info->name, si->name, sizeof(si->name)); 99 memcpy(&lgr_info->lpar_number, &si->lpar_number, 100 sizeof(lgr_info->lpar_number)); 101 } 102 103 /* 104 * Fill LGR info with 3.2.2 stsi data 105 */ 106 static void lgr_stsi_3_2_2(struct lgr_info *lgr_info) 107 { 108 struct sysinfo_3_2_2 *si = (void *) lgr_page; 109 int i; 110 111 if (stsi(si, 3, 2, 2) == -ENOSYS) 112 return; 113 for (i = 0; i < min_t(u8, si->count, VM_LEVEL_MAX); i++) { 114 cpascii(lgr_info->vm[i].name, si->vm[i].name, 115 sizeof(si->vm[i].name)); 116 cpascii(lgr_info->vm[i].cpi, si->vm[i].cpi, 117 sizeof(si->vm[i].cpi)); 118 } 119 lgr_info->vm_count = si->count; 120 } 121 122 /* 123 * Fill LGR info with current data 124 */ 125 static void lgr_info_get(struct lgr_info *lgr_info) 126 { 127 memset(lgr_info, 0, sizeof(*lgr_info)); 128 stfle(lgr_info->stfle_fac_list, ARRAY_SIZE(lgr_info->stfle_fac_list)); 129 lgr_info->level = stsi_0(); 130 if (lgr_info->level == -ENOSYS) 131 return; 132 if (lgr_info->level >= 1) 133 lgr_stsi_1_1_1(lgr_info); 134 if (lgr_info->level >= 2) 135 lgr_stsi_2_2_2(lgr_info); 136 if (lgr_info->level >= 3) 137 lgr_stsi_3_2_2(lgr_info); 138 } 139 140 /* 141 * Check if LGR info has changed and if yes log new LGR info to s390dbf 142 */ 143 void lgr_info_log(void) 144 { 145 static DEFINE_SPINLOCK(lgr_info_lock); 146 unsigned long flags; 147 148 if (!spin_trylock_irqsave(&lgr_info_lock, flags)) 149 return; 150 lgr_info_get(&lgr_info_cur); 151 if (memcmp(&lgr_info_last, &lgr_info_cur, sizeof(lgr_info_cur)) != 0) { 152 debug_event(lgr_dbf, 1, &lgr_info_cur, sizeof(lgr_info_cur)); 153 lgr_info_last = lgr_info_cur; 154 } 155 spin_unlock_irqrestore(&lgr_info_lock, flags); 156 } 157 EXPORT_SYMBOL_GPL(lgr_info_log); 158 159 static void lgr_timer_set(void); 160 161 /* 162 * LGR timer callback 163 */ 164 static void lgr_timer_fn(unsigned long ignored) 165 { 166 lgr_info_log(); 167 lgr_timer_set(); 168 } 169 170 static struct timer_list lgr_timer = 171 TIMER_DEFERRED_INITIALIZER(lgr_timer_fn, 0, 0); 172 173 /* 174 * Setup next LGR timer 175 */ 176 static void lgr_timer_set(void) 177 { 178 mod_timer(&lgr_timer, jiffies + LGR_TIMER_INTERVAL_SECS * HZ); 179 } 180 181 /* 182 * Initialize LGR: Add s390dbf, write initial lgr_info and setup timer 183 */ 184 static int __init lgr_init(void) 185 { 186 lgr_dbf = debug_register("lgr", 1, 1, sizeof(struct lgr_info)); 187 if (!lgr_dbf) 188 return -ENOMEM; 189 debug_register_view(lgr_dbf, &debug_hex_ascii_view); 190 lgr_info_get(&lgr_info_last); 191 debug_event(lgr_dbf, 1, &lgr_info_last, sizeof(lgr_info_last)); 192 lgr_timer_set(); 193 return 0; 194 } 195 module_init(lgr_init); 196