sysctl: move some boundary constants from sysctl.c to sysctl_vals

sysctl has helpers which let us specify boundary values for a min or max
int value.  Since these are used for a boundary check only they don't
change, so move these variables to sysctl_vals to avoid adding duplicate
variables.  This will help with our cleanup of kernel/sysctl.c.

[akpm@linux-foundation.org: update it for "mm/pagealloc: sysctl: change watermark_scale_factor max limit to 30%"]
[mcgrof@kernel.org: major rebase]

Link: https://lkml.kernel.org/r/20211123202347.818157-3-mcgrof@kernel.org
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Amir Goldstein <amir73il@gmail.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Qing Wang <wangqing@vivo.com>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Stephen Kitt <steve@sk2.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Antti Palosaari <crope@iki.fi>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: David Airlie <airlied@linux.ie>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Julia Lawall <julia.lawall@inria.fr>
Cc: Lukas Middendorf <kernel@tuxforce.de>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Phillip Potter <phil@philpotter.co.uk>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: James E.J. Bottomley <jejb@linux.ibm.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: John Ogness <john.ogness@linutronix.de>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index 55a5497..cd8bbf1 100644 (file)
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -26,7 +26,7 @@ static const struct file_operations proc_sys_dir_file_operations;
 static const struct inode_operations proc_sys_dir_operations;
 
 /* shared constants to be used in various sysctls */
-const int sysctl_vals[] = { 0, 1, INT_MAX };
+const int sysctl_vals[] = { -1, 0, 1, 2, 4, 100, 200, 1000, 3000, INT_MAX };
 EXPORT_SYMBOL(sysctl_vals);
 
 /* Support for permanently empty directories */

diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index d3ab796..47cf70c 100644 (file)
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -38,9 +38,16 @@ struct ctl_table_header;
 struct ctl_dir;
 
 /* Keep the same order as in fs/proc/proc_sysctl.c */
-#define SYSCTL_ZERO    ((void *)&sysctl_vals[0])
-#define SYSCTL_ONE     ((void *)&sysctl_vals[1])
-#define SYSCTL_INT_MAX ((void *)&sysctl_vals[2])
+#define SYSCTL_NEG_ONE                 ((void *)&sysctl_vals[0])
+#define SYSCTL_ZERO                    ((void *)&sysctl_vals[1])
+#define SYSCTL_ONE                     ((void *)&sysctl_vals[2])
+#define SYSCTL_TWO                     ((void *)&sysctl_vals[3])
+#define SYSCTL_FOUR                    ((void *)&sysctl_vals[4])
+#define SYSCTL_ONE_HUNDRED             ((void *)&sysctl_vals[5])
+#define SYSCTL_TWO_HUNDRED             ((void *)&sysctl_vals[6])
+#define SYSCTL_ONE_THOUSAND            ((void *)&sysctl_vals[7])
+#define SYSCTL_THREE_THOUSAND          ((void *)&sysctl_vals[8])
+#define SYSCTL_INT_MAX                 ((void *)&sysctl_vals[9])
 
 extern const int sysctl_vals[];
 

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index ef77be5..901a9df 100644 (file)
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -114,16 +114,9 @@
 static int sixty = 60;
 #endif
 
-static int __maybe_unused neg_one = -1;
-static int __maybe_unused two = 2;
-static int __maybe_unused four = 4;
 static unsigned long zero_ul;
 static unsigned long one_ul = 1;
 static unsigned long long_max = LONG_MAX;
-static int one_hundred = 100;
-static int two_hundred = 200;
-static int one_thousand = 1000;
-static int three_thousand = 3000;
 #ifdef CONFIG_PRINTK
 static int ten_thousand = 10000;
 #endif
@@ -1964,7 +1957,7 @@ static struct ctl_table kern_table[] = {
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
-               .extra1         = &neg_one,
+               .extra1         = SYSCTL_NEG_ONE,
                .extra2         = SYSCTL_ONE,
        },
 #endif
@@ -2306,7 +2299,7 @@ static struct ctl_table kern_table[] = {
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax_sysadmin,
                .extra1         = SYSCTL_ZERO,
-               .extra2         = &two,
+               .extra2         = SYSCTL_TWO,
        },
 #endif
        {
@@ -2566,7 +2559,7 @@ static struct ctl_table kern_table[] = {
                .maxlen         = sizeof(int),
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
-               .extra1         = &neg_one,
+               .extra1         = SYSCTL_NEG_ONE,
        },
 #endif
 #ifdef CONFIG_RT_MUTEXES
@@ -2628,7 +2621,7 @@ static struct ctl_table kern_table[] = {
                .mode           = 0644,
                .proc_handler   = perf_cpu_time_max_percent_handler,
                .extra1         = SYSCTL_ZERO,
-               .extra2         = &one_hundred,
+               .extra2         = SYSCTL_ONE_HUNDRED,
        },
        {
                .procname       = "perf_event_max_stack",
@@ -2646,7 +2639,7 @@ static struct ctl_table kern_table[] = {
                .mode           = 0644,
                .proc_handler   = perf_event_max_stack_handler,
                .extra1         = SYSCTL_ZERO,
-               .extra2         = &one_thousand,
+               .extra2         = SYSCTL_ONE_THOUSAND,
        },
 #endif
        {
@@ -2677,7 +2670,7 @@ static struct ctl_table kern_table[] = {
                .mode           = 0644,
                .proc_handler   = bpf_unpriv_handler,
                .extra1         = SYSCTL_ZERO,
-               .extra2         = &two,
+               .extra2         = SYSCTL_TWO,
        },
        {
                .procname       = "bpf_stats_enabled",
@@ -2731,7 +2724,7 @@ static struct ctl_table vm_table[] = {
                .mode           = 0644,
                .proc_handler   = overcommit_policy_handler,
                .extra1         = SYSCTL_ZERO,
-               .extra2         = &two,
+               .extra2         = SYSCTL_TWO,
        },
        {
                .procname       = "panic_on_oom",
@@ -2740,7 +2733,7 @@ static struct ctl_table vm_table[] = {
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = SYSCTL_ZERO,
-               .extra2         = &two,
+               .extra2         = SYSCTL_TWO,
        },
        {
                .procname       = "oom_kill_allocating_task",
@@ -2785,7 +2778,7 @@ static struct ctl_table vm_table[] = {
                .mode           = 0644,
                .proc_handler   = dirty_background_ratio_handler,
                .extra1         = SYSCTL_ZERO,
-               .extra2         = &one_hundred,
+               .extra2         = SYSCTL_ONE_HUNDRED,
        },
        {
                .procname       = "dirty_background_bytes",
@@ -2802,7 +2795,7 @@ static struct ctl_table vm_table[] = {
                .mode           = 0644,
                .proc_handler   = dirty_ratio_handler,
                .extra1         = SYSCTL_ZERO,
-               .extra2         = &one_hundred,
+               .extra2         = SYSCTL_ONE_HUNDRED,
        },
        {
                .procname       = "dirty_bytes",
@@ -2842,7 +2835,7 @@ static struct ctl_table vm_table[] = {
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = SYSCTL_ZERO,
-               .extra2         = &two_hundred,
+               .extra2         = SYSCTL_TWO_HUNDRED,
        },
 #ifdef CONFIG_HUGETLB_PAGE
        {
@@ -2899,7 +2892,7 @@ static struct ctl_table vm_table[] = {
                .mode           = 0200,
                .proc_handler   = drop_caches_sysctl_handler,
                .extra1         = SYSCTL_ONE,
-               .extra2         = &four,
+               .extra2         = SYSCTL_FOUR,
        },
 #ifdef CONFIG_COMPACTION
        {
@@ -2916,7 +2909,7 @@ static struct ctl_table vm_table[] = {
                .mode           = 0644,
                .proc_handler   = compaction_proactiveness_sysctl_handler,
                .extra1         = SYSCTL_ZERO,
-               .extra2         = &one_hundred,
+               .extra2         = SYSCTL_ONE_HUNDRED,
        },
        {
                .procname       = "extfrag_threshold",
@@ -2961,7 +2954,7 @@ static struct ctl_table vm_table[] = {
                .mode           = 0644,
                .proc_handler   = watermark_scale_factor_sysctl_handler,
                .extra1         = SYSCTL_ONE,
-               .extra2         = &three_thousand,
+               .extra2         = SYSCTL_THREE_THOUSAND,
        },
        {
                .procname       = "percpu_pagelist_high_fraction",
@@ -3040,7 +3033,7 @@ static struct ctl_table vm_table[] = {
                .mode           = 0644,
                .proc_handler   = sysctl_min_unmapped_ratio_sysctl_handler,
                .extra1         = SYSCTL_ZERO,
-               .extra2         = &one_hundred,
+               .extra2         = SYSCTL_ONE_HUNDRED,
        },
        {
                .procname       = "min_slab_ratio",
@@ -3049,7 +3042,7 @@ static struct ctl_table vm_table[] = {
                .mode           = 0644,
                .proc_handler   = sysctl_min_slab_ratio_sysctl_handler,
                .extra1         = SYSCTL_ZERO,
-               .extra2         = &one_hundred,
+               .extra2         = SYSCTL_ONE_HUNDRED,
        },
 #endif
 #ifdef CONFIG_SMP
@@ -3339,7 +3332,7 @@ static struct ctl_table fs_table[] = {
                .mode           = 0600,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = SYSCTL_ZERO,
-               .extra2         = &two,
+               .extra2         = SYSCTL_TWO,
        },
        {
                .procname       = "protected_regular",
@@ -3348,7 +3341,7 @@ static struct ctl_table fs_table[] = {
                .mode           = 0600,
                .proc_handler   = proc_dointvec_minmax,
                .extra1         = SYSCTL_ZERO,
-               .extra2         = &two,
+               .extra2         = SYSCTL_TWO,
        },
        {
                .procname       = "suid_dumpable",
@@ -3357,7 +3350,7 @@ static struct ctl_table fs_table[] = {
                .mode           = 0644,
                .proc_handler   = proc_dointvec_minmax_coredump,
                .extra1         = SYSCTL_ZERO,
-               .extra2         = &two,
+               .extra2         = SYSCTL_TWO,
        },
 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
        {