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1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) 2020 Cyril Hrubis <chrubis@suse.cz>
4  */
5 
6 /*
7  * [Description]
8  *
9  * After a call to unshare(CLONE_NEWTIME) a new timer namespace is created, the
10  * process that has called the unshare() can adjust offsets for CLOCK_MONOTONIC
11  * and CLOCK_BOOTTIME for its children by writing to the '/proc/self/timens_offsets'.
12  *
13  * The child processes also switch to the initial parent namespace and checks
14  * that the offset is set to 0.
15  */
16 
17 #define _GNU_SOURCE
18 #include "time64_variants.h"
19 #include "tst_safe_clocks.h"
20 #include "tst_timer.h"
21 #include "lapi/namespaces_constants.h"
22 
23 static struct tcase {
24 	int clk_id;
25 	int clk_off;
26 	int off;
27 } tcases[] = {
28 	{CLOCK_MONOTONIC, CLOCK_MONOTONIC, 10},
29 	{CLOCK_BOOTTIME, CLOCK_BOOTTIME, 10},
30 
31 	{CLOCK_MONOTONIC, CLOCK_MONOTONIC, -10},
32 	{CLOCK_BOOTTIME, CLOCK_BOOTTIME, -10},
33 
34 	{CLOCK_MONOTONIC_RAW, CLOCK_MONOTONIC, 100},
35 	{CLOCK_MONOTONIC_COARSE, CLOCK_MONOTONIC, 100},
36 };
37 
38 static struct tst_ts now, then, parent_then;
39 static int parent_ns;
40 
41 static struct time64_variants variants[] = {
42 	{ .clock_gettime = libc_clock_gettime, .ts_type = TST_LIBC_TIMESPEC, .desc = "vDSO or syscall with libc spec"},
43 
44 #if (__NR_clock_gettime != __LTP__NR_INVALID_SYSCALL)
45 	{ .clock_gettime = sys_clock_gettime, .ts_type = TST_KERN_OLD_TIMESPEC, .desc = "syscall with old kernel spec"},
46 #endif
47 
48 #if (__NR_clock_gettime64 != __LTP__NR_INVALID_SYSCALL)
49 	{ .clock_gettime = sys_clock_gettime64, .ts_type = TST_KERN_TIMESPEC, .desc = "syscall time64 with kernel spec"},
50 #endif
51 };
52 
child(struct time64_variants * tv,struct tcase * tc)53 static void child(struct time64_variants *tv, struct tcase *tc)
54 {
55 	long long diff;
56 
57 	if (tv->clock_gettime(tc->clk_id, tst_ts_get(&then))) {
58 		tst_res(TFAIL | TERRNO, "clock_gettime(%s) failed",
59 			tst_clock_name(tc->clk_id));
60 		return;
61 	}
62 
63 	SAFE_SETNS(parent_ns, CLONE_NEWTIME);
64 
65 	if (tv->clock_gettime(tc->clk_id, tst_ts_get(&parent_then))) {
66 		tst_res(TFAIL | TERRNO, "clock_gettime(%s) failed",
67 			tst_clock_name(tc->clk_id));
68 		return;
69 	}
70 
71 	diff = tst_ts_diff_ms(then, now);
72 
73 	if (diff - tc->off * 1000 > 10) {
74 		tst_res(TFAIL, "Wrong offset (%s) read %llims",
75 		        tst_clock_name(tc->clk_id), diff);
76 	} else {
77 		tst_res(TPASS, "Offset (%s) is correct %llims",
78 		        tst_clock_name(tc->clk_id), diff);
79 	}
80 
81 	diff = tst_ts_diff_ms(parent_then, now);
82 
83 	if (diff > 10) {
84 		tst_res(TFAIL, "Wrong offset (%s) read %llims",
85 		        tst_clock_name(tc->clk_id), diff);
86 	} else {
87 		tst_res(TPASS, "Offset (%s) is correct %llims",
88 		        tst_clock_name(tc->clk_id), diff);
89 	}
90 }
91 
verify_ns_clock(unsigned int n)92 static void verify_ns_clock(unsigned int n)
93 {
94 	struct time64_variants *tv = &variants[tst_variant];
95 	struct tcase *tc = &tcases[n];
96 
97 	SAFE_UNSHARE(CLONE_NEWTIME);
98 
99 	SAFE_FILE_PRINTF("/proc/self/timens_offsets", "%d %d 0",
100 	                 tc->clk_off, tc->off);
101 
102 	if (tv->clock_gettime(tc->clk_id, tst_ts_get(&now))) {
103 		tst_res(TFAIL | TERRNO, "%d clock_gettime(%s) failed",
104 			__LINE__, tst_clock_name(tc->clk_id));
105 		return;
106 	}
107 
108 	if (!SAFE_FORK())
109 		child(tv, tc);
110 }
111 
setup(void)112 static void setup(void)
113 {
114 	struct time64_variants *tv = &variants[tst_variant];
115 
116 	now.type = then.type = parent_then.type = tv->ts_type;
117 	tst_res(TINFO, "Testing variant: %s", variants[tst_variant].desc);
118 	parent_ns = SAFE_OPEN("/proc/self/ns/time_for_children", O_RDONLY);
119 }
120 
cleanup(void)121 static void cleanup(void)
122 {
123 	SAFE_CLOSE(parent_ns);
124 }
125 
126 static struct tst_test test = {
127 	.setup = setup,
128 	.cleanup = cleanup,
129 	.tcnt = ARRAY_SIZE(tcases),
130 	.test = verify_ns_clock,
131 	.test_variants = ARRAY_SIZE(variants),
132 	.needs_root = 1,
133 	.forks_child = 1,
134 	.needs_kconfigs = (const char *[]) {
135 		"CONFIG_TIME_NS=y",
136 		NULL
137 	}
138 };
139