[RFC PATCH 02/39] test_sysctl: convert bounds to numeric values

[wen.yang@linux.dev]

From: Wen Yang <wen.yang@linux.dev>

The debug module still passes extra pointers for its numeric ranges.
Convert them to numeric min/max so it exercises the same shape as the
rest of the tree, and keep the dynamic-value entry's context in data for
now; the priv conversion comes later.

Suggested-by: Joel Granados <joel.granados@kernel.org>
Signed-off-by: Wen Yang <wen.yang@linux.dev>
---
 lib/test_sysctl.c | 135 +++++++++++++++++++++++++++++++++++++---------
 1 file changed, 109 insertions(+), 26 deletions(-)

diff --git a/lib/test_sysctl.c b/lib/test_sysctl.c
index eed2cc1bea82..1411896fdbd0 100644
--- a/lib/test_sysctl.c
+++ b/lib/test_sysctl.c
@@ -15,7 +15,6 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include <linux/init.h>
-#include <linux/limits.h>
 #include <linux/jiffies.h>
 #include <linux/list.h>
 #include <linux/module.h>
@@ -28,8 +27,6 @@
 #include <linux/delay.h>
 #include <linux/vmalloc.h>
 
-static int i_zero;
-static int i_one_hundred = 100;
 static int match_int_ok = 1;
 
 enum {
@@ -43,6 +40,12 @@ enum {
 };
 
 static struct ctl_table_header *ctl_headers[TEST_H_SIZE] = {};
+
+struct test_sysctl_range_context {
+	int value;
+	int limit;
+};
+
 struct test_sysctl_data {
 	int int_0001;
 	int int_0002;
@@ -56,6 +59,11 @@ struct test_sysctl_data {
 
 	unsigned int uint_0001;
 
+	struct test_sysctl_range_context dynamic;
+	int int_zero;
+	unsigned long ulong_zero;
+	u8 u8_zero;
+
 	char string_0001[65];
 
 #define SYSCTL_TEST_BITMAP_SIZE	65536
@@ -80,9 +88,25 @@ static struct test_sysctl_data test_data = {
 
 	.uint_0001 = 314,
 
+	.dynamic = { .value = 0, .limit = 100 },
+
 	.string_0001 = "(none)",
 };
 
+/* The registered data is typed context, not the backing integer. */
+static int test_sysctl_dynamic_value(const struct ctl_table *table, int dir,
+				     void *buffer, size_t *lenp, loff_t *ppos)
+{
+	struct test_sysctl_range_context *context = table->data;
+	struct ctl_table resolved = *table;
+
+	resolved.data = &context->value;
+	resolved.maxlen = sizeof(context->value);
+	resolved.min = INT_MIN;
+	resolved.max = READ_ONCE(context->limit);
+	return proc_dointvec_minmax(&resolved, dir, buffer, lenp, ppos);
+}
+
 /* These are all under /proc/sys/debug/test_sysctl/ */
 static const struct ctl_table test_table[] = {
 	{
@@ -91,8 +115,8 @@ static const struct ctl_table test_table[] = {
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec_minmax,
-		.extra1		= &i_zero,
-		.extra2         = &i_one_hundred,
+		.min		= 0,
+		.max		= 100,
 	},
 	{
 		.procname	= "int_0002",
@@ -100,6 +124,8 @@ static const struct ctl_table test_table[] = {
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec,
+		.min		= INT_MIN,
+		.max		= INT_MAX,
 	},
 	{
 		.procname	= "int_0003",
@@ -107,6 +133,8 @@ static const struct ctl_table test_table[] = {
 		.maxlen		= sizeof(test_data.int_0003),
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec,
+		.min		= INT_MIN,
+		.max		= INT_MAX,
 	},
 	{
 		.procname	= "match_int",
@@ -114,6 +142,8 @@ static const struct ctl_table test_table[] = {
 		.maxlen		= sizeof(match_int_ok),
 		.mode		= 0444,
 		.proc_handler	= proc_dointvec,
+		.min		= INT_MIN,
+		.max		= INT_MAX,
 	},
 	{
 		.procname	= "boot_int",
@@ -121,8 +151,8 @@ static const struct ctl_table test_table[] = {
 		.maxlen		= sizeof(test_data.boot_int),
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec,
-		.extra1		= SYSCTL_ZERO,
-		.extra2         = SYSCTL_ONE,
+		.min		= 0,
+		.max		= 1,
 	},
 	{
 		.procname	= "int_jiffies",
@@ -130,6 +160,8 @@ static const struct ctl_table test_table[] = {
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec_jiffies,
+		.min		= INT_MIN,
+		.max		= INT_MAX,
 	},
 	{
 		.procname	= "int_ms_jiffies",
@@ -137,6 +169,8 @@ static const struct ctl_table test_table[] = {
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec_ms_jiffies,
+		.min		= INT_MIN,
+		.max		= INT_MAX,
 	},
 	{
 		.procname	= "int_userhz_jiffies",
@@ -144,6 +178,8 @@ static const struct ctl_table test_table[] = {
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
 		.proc_handler	= proc_dointvec_userhz_jiffies,
+		.min		= INT_MIN,
+		.max		= INT_MAX,
 	},
 	{
 		.procname	= "uint_0001",
@@ -151,6 +187,8 @@ static const struct ctl_table test_table[] = {
 		.maxlen		= sizeof(unsigned int),
 		.mode		= 0644,
 		.proc_handler	= proc_douintvec,
+		.min		= 0,
+		.max		= UINT_MAX,
 	},
 	{
 		.procname	= "string_0001",
@@ -166,28 +204,73 @@ static const struct ctl_table test_table[] = {
 		.mode		= 0644,
 		.proc_handler	= proc_do_large_bitmap,
 	},
+	{
+		.procname	= "dynamic_limit",
+		.data		= &test_data.dynamic.limit,
+		.maxlen		= sizeof(test_data.dynamic.limit),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+		.min		= INT_MIN,
+		.max		= INT_MAX,
+	},
+	{
+		.procname	= "dynamic_value",
+		.data		= &test_data.dynamic,
+		.maxlen		= sizeof(test_data.dynamic),
+		.mode		= 0644,
+		.proc_handler	= test_sysctl_dynamic_value,
+		.min		= 0,
+		.max		= ULONG_MAX,
+	},
+	{
+		.procname	= "int_zero",
+		.data		= &test_data.int_zero,
+		.maxlen		= sizeof(test_data.int_zero),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.min		= 0,
+		.max		= 0,
+	},
+	{
+		.procname	= "ulong_zero",
+		.data		= &test_data.ulong_zero,
+		.maxlen		= sizeof(test_data.ulong_zero),
+		.mode		= 0644,
+		.proc_handler	= proc_doulongvec_minmax,
+		.min		= 0,
+		.max		= 0,
+	},
+	{
+		.procname	= "u8_zero",
+		.data		= &test_data.u8_zero,
+		.maxlen		= sizeof(test_data.u8_zero),
+		.mode		= 0644,
+		.proc_handler	= proc_dou8vec_minmax,
+		.min		= 0,
+		.max		= 0,
+	},
 };
 
 static void test_sysctl_calc_match_int_ok(void)
 {
 	int i;
 
-	struct {
+	const struct {
 		int defined;
 		int wanted;
 	} match_int[] = {
-		{.defined = *(int *)SYSCTL_ZERO,	.wanted = 0},
-		{.defined = *(int *)SYSCTL_ONE,		.wanted = 1},
-		{.defined = *(int *)SYSCTL_TWO,		.wanted = 2},
-		{.defined = *(int *)SYSCTL_THREE,	.wanted = 3},
-		{.defined = *(int *)SYSCTL_FOUR,	.wanted = 4},
-		{.defined = *(int *)SYSCTL_ONE_HUNDRED, .wanted = 100},
-		{.defined = *(int *)SYSCTL_TWO_HUNDRED,	.wanted = 200},
-		{.defined = *(int *)SYSCTL_ONE_THOUSAND, .wanted = 1000},
-		{.defined = *(int *)SYSCTL_THREE_THOUSAND, .wanted = 3000},
-		{.defined = *(int *)SYSCTL_INT_MAX,	.wanted = INT_MAX},
-		{.defined = *(int *)SYSCTL_MAXOLDUID,	.wanted = 65535},
-		{.defined = *(int *)SYSCTL_NEG_ONE,	.wanted = -1},
+		{ .defined = 0, .wanted = 0 },
+		{ .defined = 1, .wanted = 1 },
+		{ .defined = 2, .wanted = 2 },
+		{ .defined = 3, .wanted = 3 },
+		{ .defined = 4, .wanted = 4 },
+		{ .defined = 100, .wanted = 100 },
+		{ .defined = 200, .wanted = 200 },
+		{ .defined = 1000, .wanted = 1000 },
+		{ .defined = 3000, .wanted = 3000 },
+		{ .defined = INT_MAX, .wanted = INT_MAX },
+		{ .defined = 65535, .wanted = 65535 },
+		{ .defined = -1, .wanted = -1 },
 	};
 
 	for (i = 0; i < ARRAY_SIZE(match_int); i++)
@@ -282,8 +365,8 @@ static const struct ctl_table table_u8_over[] = {
 		.maxlen		= sizeof(u8),
 		.mode		= 0644,
 		.proc_handler	= proc_dou8vec_minmax,
-		.extra1		= SYSCTL_FOUR,
-		.extra2		= SYSCTL_ONE_THOUSAND,
+		.min		= 4,
+		.max		= 1000,
 	},
 };
 
@@ -294,8 +377,8 @@ static const struct ctl_table table_u8_under[] = {
 		.maxlen		= sizeof(u8),
 		.mode		= 0644,
 		.proc_handler	= proc_dou8vec_minmax,
-		.extra1		= SYSCTL_NEG_ONE,
-		.extra2		= SYSCTL_ONE_HUNDRED,
+		.min		= ULONG_MAX,
+		.max		= 100,
 	},
 };
 
@@ -306,8 +389,8 @@ static const struct ctl_table table_u8_valid[] = {
 		.maxlen		= sizeof(u8),
 		.mode		= 0644,
 		.proc_handler	= proc_dou8vec_minmax,
-		.extra1		= SYSCTL_ZERO,
-		.extra2		= SYSCTL_TWO_HUNDRED,
+		.min		= 0,
+		.max		= 200,
 	},
 };
 
-- 
2.25.1