1 | /* |
2 | * Copyright (c) 2013 Apple Inc. All rights reserved. |
3 | * |
4 | * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ |
5 | * |
6 | * This file contains Original Code and/or Modifications of Original Code |
7 | * as defined in and that are subject to the Apple Public Source License |
8 | * Version 2.0 (the 'License'). You may not use this file except in |
9 | * compliance with the License. The rights granted to you under the License |
10 | * may not be used to create, or enable the creation or redistribution of, |
11 | * unlawful or unlicensed copies of an Apple operating system, or to |
12 | * circumvent, violate, or enable the circumvention or violation of, any |
13 | * terms of an Apple operating system software license agreement. |
14 | * |
15 | * Please obtain a copy of the License at |
16 | * http://www.opensource.apple.com/apsl/ and read it before using this file. |
17 | * |
18 | * The Original Code and all software distributed under the License are |
19 | * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER |
20 | * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, |
21 | * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, |
22 | * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. |
23 | * Please see the License for the specific language governing rights and |
24 | * limitations under the License. |
25 | * |
26 | * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ |
27 | */ |
28 | #include <mach/mach_types.h> |
29 | #include <mach/host_info.h> |
30 | #include <kern/locks.h> |
31 | #include <kern/ecc.h> |
32 | #include <kern/spl.h> |
33 | #include <pexpert/pexpert.h> |
34 | #include <libkern/OSAtomic.h> |
35 | |
36 | /* |
37 | * ECC data. Not really KPCs, but this still seems like the |
38 | * best home for this code. |
39 | * |
40 | * Circular buffer of events. When we fill up, drop data. |
41 | */ |
42 | #define ECC_EVENT_BUFFER_COUNT 5 |
43 | struct ecc_event ecc_data[ECC_EVENT_BUFFER_COUNT]; |
44 | static uint32_t ecc_data_next_read; |
45 | static uint32_t ecc_data_next_write; |
46 | static boolean_t ecc_data_empty = TRUE; // next read == next write : empty or full? |
47 | static lck_grp_t *ecc_data_lock_group; |
48 | static lck_spin_t ecc_data_lock; |
49 | static uint32_t ecc_correction_count; |
50 | |
51 | void |
52 | ecc_log_init() |
53 | { |
54 | ecc_data_lock_group = lck_grp_alloc_init("ecc-data" , NULL); |
55 | lck_spin_init(&ecc_data_lock, ecc_data_lock_group, NULL); |
56 | OSMemoryBarrier(); |
57 | } |
58 | |
59 | uint32_t |
60 | ecc_log_get_correction_count() |
61 | { |
62 | return ecc_correction_count; |
63 | } |
64 | |
65 | kern_return_t |
66 | ecc_log_record_event(const struct ecc_event *ev) |
67 | { |
68 | spl_t x; |
69 | |
70 | if (ev->count > ECC_EVENT_INFO_DATA_ENTRIES) { |
71 | panic("Count of %u on ecc event is too large." , (unsigned)ev->count); |
72 | } |
73 | |
74 | x = splhigh(); |
75 | lck_spin_lock(&ecc_data_lock); |
76 | |
77 | ecc_correction_count++; |
78 | |
79 | if (ecc_data_next_read == ecc_data_next_write && !ecc_data_empty) { |
80 | lck_spin_unlock(&ecc_data_lock); |
81 | splx(x); |
82 | return KERN_FAILURE; |
83 | } |
84 | |
85 | bcopy(ev, &ecc_data[ecc_data_next_write], sizeof(*ev)); |
86 | ecc_data_next_write++; |
87 | ecc_data_next_write %= ECC_EVENT_BUFFER_COUNT; |
88 | ecc_data_empty = FALSE; |
89 | |
90 | lck_spin_unlock(&ecc_data_lock); |
91 | splx(x); |
92 | |
93 | return KERN_SUCCESS; |
94 | } |
95 | |
96 | |
97 | kern_return_t |
98 | ecc_log_get_next_event(struct ecc_event *ev) |
99 | { |
100 | spl_t x; |
101 | |
102 | x = splhigh(); |
103 | lck_spin_lock(&ecc_data_lock); |
104 | |
105 | if (ecc_data_empty) { |
106 | assert(ecc_data_next_write == ecc_data_next_read); |
107 | |
108 | lck_spin_unlock(&ecc_data_lock); |
109 | splx(x); |
110 | return KERN_FAILURE; |
111 | } |
112 | |
113 | bcopy(&ecc_data[ecc_data_next_read], ev, sizeof(*ev)); |
114 | ecc_data_next_read++; |
115 | ecc_data_next_read %= ECC_EVENT_BUFFER_COUNT; |
116 | |
117 | if (ecc_data_next_read == ecc_data_next_write) { |
118 | ecc_data_empty = TRUE; |
119 | } |
120 | |
121 | lck_spin_unlock(&ecc_data_lock); |
122 | splx(x); |
123 | |
124 | return KERN_SUCCESS; |
125 | } |
126 | |