diff mbox series

[3/5] sysctl: remove all extern declaration from sysctl.c

Message ID 20200424064338.538313-4-hch@lst.de (mailing list archive)
State New, archived
Headers show
Series [1/5] bpf-cgroup: remove unused exports | expand

Commit Message

Christoph Hellwig April 24, 2020, 6:43 a.m. UTC
Extern declarations in .c files are a bad style and can lead to
mismatches.  Use existing definitions in headers where they exist,
and otherwise move the external declarations to suitable header
files.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 include/linux/coredump.h |  4 ++++
 include/linux/file.h     |  2 ++
 include/linux/mm.h       |  2 ++
 include/linux/mmzone.h   |  2 ++
 include/linux/pid.h      |  3 +++
 include/linux/sysctl.h   |  8 +++++++
 kernel/sysctl.c          | 45 +++-------------------------------------
 7 files changed, 24 insertions(+), 42 deletions(-)

Comments

Stephen Rothwell May 4, 2020, 1:25 a.m. UTC | #1
Hi Christoph,

On Fri, 24 Apr 2020 08:43:36 +0200 Christoph Hellwig <hch@lst.de> wrote:
>
> Extern declarations in .c files are a bad style and can lead to
> mismatches.  Use existing definitions in headers where they exist,
> and otherwise move the external declarations to suitable header
> files.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>
> ---
>  include/linux/coredump.h |  4 ++++
>  include/linux/file.h     |  2 ++
>  include/linux/mm.h       |  2 ++
>  include/linux/mmzone.h   |  2 ++
>  include/linux/pid.h      |  3 +++
>  include/linux/sysctl.h   |  8 +++++++
>  kernel/sysctl.c          | 45 +++-------------------------------------
>  7 files changed, 24 insertions(+), 42 deletions(-)

A couple of suggestions for another patch (since this one is in a
shared branch in Al's tree now):

There is an "extern struct ctl_table random_table[];" in
drivers/char/random.c which is redundant now (in fact always was).

There is already an "extern struct ctl_table epoll_table[];" in
include/linux/poll.h, so could have included that in kernel/sysctl.c
instead of adding the new one in include/linux/sysctl.h
Kees Cook May 4, 2020, 6:42 p.m. UTC | #2
On Fri, Apr 24, 2020 at 08:43:36AM +0200, Christoph Hellwig wrote:
> Extern declarations in .c files are a bad style and can lead to
> mismatches.  Use existing definitions in headers where they exist,
> and otherwise move the external declarations to suitable header
> files.
> 
> Signed-off-by: Christoph Hellwig <hch@lst.de>

Reviewed-by: Kees Cook <keescook@chromium.org>

-Kees

> ---
>  include/linux/coredump.h |  4 ++++
>  include/linux/file.h     |  2 ++
>  include/linux/mm.h       |  2 ++
>  include/linux/mmzone.h   |  2 ++
>  include/linux/pid.h      |  3 +++
>  include/linux/sysctl.h   |  8 +++++++
>  kernel/sysctl.c          | 45 +++-------------------------------------
>  7 files changed, 24 insertions(+), 42 deletions(-)
> 
> diff --git a/include/linux/coredump.h b/include/linux/coredump.h
> index abf4b4e65dbb9..7a899e83835d5 100644
> --- a/include/linux/coredump.h
> +++ b/include/linux/coredump.h
> @@ -22,4 +22,8 @@ extern void do_coredump(const kernel_siginfo_t *siginfo);
>  static inline void do_coredump(const kernel_siginfo_t *siginfo) {}
>  #endif
>  
> +extern int core_uses_pid;
> +extern char core_pattern[];
> +extern unsigned int core_pipe_limit;
> +
>  #endif /* _LINUX_COREDUMP_H */
> diff --git a/include/linux/file.h b/include/linux/file.h
> index 142d102f285e5..122f80084a3ef 100644
> --- a/include/linux/file.h
> +++ b/include/linux/file.h
> @@ -94,4 +94,6 @@ extern void fd_install(unsigned int fd, struct file *file);
>  extern void flush_delayed_fput(void);
>  extern void __fput_sync(struct file *);
>  
> +extern unsigned int sysctl_nr_open_min, sysctl_nr_open_max;
> +
>  #endif /* __LINUX_FILE_H */
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 5a323422d783d..9c4e7e76deddc 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -3140,5 +3140,7 @@ unsigned long wp_shared_mapping_range(struct address_space *mapping,
>  				      pgoff_t first_index, pgoff_t nr);
>  #endif
>  
> +extern int sysctl_nr_trim_pages;
> +
>  #endif /* __KERNEL__ */
>  #endif /* _LINUX_MM_H */
> diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
> index f37bb8f187fc7..b2af594ef0f7c 100644
> --- a/include/linux/mmzone.h
> +++ b/include/linux/mmzone.h
> @@ -909,6 +909,7 @@ static inline int is_highmem(struct zone *zone)
>  
>  /* These two functions are used to setup the per zone pages min values */
>  struct ctl_table;
> +
>  int min_free_kbytes_sysctl_handler(struct ctl_table *, int,
>  					void __user *, size_t *, loff_t *);
>  int watermark_scale_factor_sysctl_handler(struct ctl_table *, int,
> @@ -925,6 +926,7 @@ int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *, int,
>  
>  extern int numa_zonelist_order_handler(struct ctl_table *, int,
>  			void __user *, size_t *, loff_t *);
> +extern int percpu_pagelist_fraction;
>  extern char numa_zonelist_order[];
>  #define NUMA_ZONELIST_ORDER_LEN	16
>  
> diff --git a/include/linux/pid.h b/include/linux/pid.h
> index cc896f0fc4e34..93543cbc0e6b3 100644
> --- a/include/linux/pid.h
> +++ b/include/linux/pid.h
> @@ -108,6 +108,9 @@ extern void transfer_pid(struct task_struct *old, struct task_struct *new,
>  struct pid_namespace;
>  extern struct pid_namespace init_pid_ns;
>  
> +extern int pid_max;
> +extern int pid_max_min, pid_max_max;
> +
>  /*
>   * look up a PID in the hash table. Must be called with the tasklist_lock
>   * or rcu_read_lock() held.
> diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
> index 02fa84493f237..36143ca40b56b 100644
> --- a/include/linux/sysctl.h
> +++ b/include/linux/sysctl.h
> @@ -207,7 +207,15 @@ void unregister_sysctl_table(struct ctl_table_header * table);
>  
>  extern int sysctl_init(void);
>  
> +extern int pwrsw_enabled;
> +extern int unaligned_enabled;
> +extern int unaligned_dump_stack;
> +extern int no_unaligned_warning;
> +
>  extern struct ctl_table sysctl_mount_point[];
> +extern struct ctl_table random_table[];
> +extern struct ctl_table firmware_config_table[];
> +extern struct ctl_table epoll_table[];
>  
>  #else /* CONFIG_SYSCTL */
>  static inline struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index 99d27acf46465..31b934865ebc3 100644
> --- a/kernel/sysctl.c
> +++ b/kernel/sysctl.c
> @@ -68,6 +68,9 @@
>  #include <linux/bpf.h>
>  #include <linux/mount.h>
>  #include <linux/userfaultfd_k.h>
> +#include <linux/coredump.h>
> +#include <linux/latencytop.h>
> +#include <linux/pid.h>
>  
>  #include "../lib/kstrtox.h"
>  
> @@ -103,22 +106,6 @@
>  
>  #if defined(CONFIG_SYSCTL)
>  
> -/* External variables not in a header file. */
> -extern int suid_dumpable;
> -#ifdef CONFIG_COREDUMP
> -extern int core_uses_pid;
> -extern char core_pattern[];
> -extern unsigned int core_pipe_limit;
> -#endif
> -extern int pid_max;
> -extern int pid_max_min, pid_max_max;
> -extern int percpu_pagelist_fraction;
> -extern int latencytop_enabled;
> -extern unsigned int sysctl_nr_open_min, sysctl_nr_open_max;
> -#ifndef CONFIG_MMU
> -extern int sysctl_nr_trim_pages;
> -#endif
> -
>  /* Constants used for minimum and  maximum */
>  #ifdef CONFIG_LOCKUP_DETECTOR
>  static int sixty = 60;
> @@ -160,24 +147,6 @@ static unsigned long hung_task_timeout_max = (LONG_MAX/HZ);
>  #ifdef CONFIG_INOTIFY_USER
>  #include <linux/inotify.h>
>  #endif
> -#ifdef CONFIG_SPARC
> -#endif
> -
> -#ifdef CONFIG_PARISC
> -extern int pwrsw_enabled;
> -#endif
> -
> -#ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
> -extern int unaligned_enabled;
> -#endif
> -
> -#ifdef CONFIG_IA64
> -extern int unaligned_dump_stack;
> -#endif
> -
> -#ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
> -extern int no_unaligned_warning;
> -#endif
>  
>  #ifdef CONFIG_PROC_SYSCTL
>  
> @@ -243,14 +212,6 @@ static struct ctl_table vm_table[];
>  static struct ctl_table fs_table[];
>  static struct ctl_table debug_table[];
>  static struct ctl_table dev_table[];
> -extern struct ctl_table random_table[];
> -#ifdef CONFIG_EPOLL
> -extern struct ctl_table epoll_table[];
> -#endif
> -
> -#ifdef CONFIG_FW_LOADER_USER_HELPER
> -extern struct ctl_table firmware_config_table[];
> -#endif
>  
>  #if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
>      defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)
> -- 
> 2.26.1
>
diff mbox series

Patch

diff --git a/include/linux/coredump.h b/include/linux/coredump.h
index abf4b4e65dbb9..7a899e83835d5 100644
--- a/include/linux/coredump.h
+++ b/include/linux/coredump.h
@@ -22,4 +22,8 @@  extern void do_coredump(const kernel_siginfo_t *siginfo);
 static inline void do_coredump(const kernel_siginfo_t *siginfo) {}
 #endif
 
+extern int core_uses_pid;
+extern char core_pattern[];
+extern unsigned int core_pipe_limit;
+
 #endif /* _LINUX_COREDUMP_H */
diff --git a/include/linux/file.h b/include/linux/file.h
index 142d102f285e5..122f80084a3ef 100644
--- a/include/linux/file.h
+++ b/include/linux/file.h
@@ -94,4 +94,6 @@  extern void fd_install(unsigned int fd, struct file *file);
 extern void flush_delayed_fput(void);
 extern void __fput_sync(struct file *);
 
+extern unsigned int sysctl_nr_open_min, sysctl_nr_open_max;
+
 #endif /* __LINUX_FILE_H */
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 5a323422d783d..9c4e7e76deddc 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -3140,5 +3140,7 @@  unsigned long wp_shared_mapping_range(struct address_space *mapping,
 				      pgoff_t first_index, pgoff_t nr);
 #endif
 
+extern int sysctl_nr_trim_pages;
+
 #endif /* __KERNEL__ */
 #endif /* _LINUX_MM_H */
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index f37bb8f187fc7..b2af594ef0f7c 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -909,6 +909,7 @@  static inline int is_highmem(struct zone *zone)
 
 /* These two functions are used to setup the per zone pages min values */
 struct ctl_table;
+
 int min_free_kbytes_sysctl_handler(struct ctl_table *, int,
 					void __user *, size_t *, loff_t *);
 int watermark_scale_factor_sysctl_handler(struct ctl_table *, int,
@@ -925,6 +926,7 @@  int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *, int,
 
 extern int numa_zonelist_order_handler(struct ctl_table *, int,
 			void __user *, size_t *, loff_t *);
+extern int percpu_pagelist_fraction;
 extern char numa_zonelist_order[];
 #define NUMA_ZONELIST_ORDER_LEN	16
 
diff --git a/include/linux/pid.h b/include/linux/pid.h
index cc896f0fc4e34..93543cbc0e6b3 100644
--- a/include/linux/pid.h
+++ b/include/linux/pid.h
@@ -108,6 +108,9 @@  extern void transfer_pid(struct task_struct *old, struct task_struct *new,
 struct pid_namespace;
 extern struct pid_namespace init_pid_ns;
 
+extern int pid_max;
+extern int pid_max_min, pid_max_max;
+
 /*
  * look up a PID in the hash table. Must be called with the tasklist_lock
  * or rcu_read_lock() held.
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index 02fa84493f237..36143ca40b56b 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -207,7 +207,15 @@  void unregister_sysctl_table(struct ctl_table_header * table);
 
 extern int sysctl_init(void);
 
+extern int pwrsw_enabled;
+extern int unaligned_enabled;
+extern int unaligned_dump_stack;
+extern int no_unaligned_warning;
+
 extern struct ctl_table sysctl_mount_point[];
+extern struct ctl_table random_table[];
+extern struct ctl_table firmware_config_table[];
+extern struct ctl_table epoll_table[];
 
 #else /* CONFIG_SYSCTL */
 static inline struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 99d27acf46465..31b934865ebc3 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -68,6 +68,9 @@ 
 #include <linux/bpf.h>
 #include <linux/mount.h>
 #include <linux/userfaultfd_k.h>
+#include <linux/coredump.h>
+#include <linux/latencytop.h>
+#include <linux/pid.h>
 
 #include "../lib/kstrtox.h"
 
@@ -103,22 +106,6 @@ 
 
 #if defined(CONFIG_SYSCTL)
 
-/* External variables not in a header file. */
-extern int suid_dumpable;
-#ifdef CONFIG_COREDUMP
-extern int core_uses_pid;
-extern char core_pattern[];
-extern unsigned int core_pipe_limit;
-#endif
-extern int pid_max;
-extern int pid_max_min, pid_max_max;
-extern int percpu_pagelist_fraction;
-extern int latencytop_enabled;
-extern unsigned int sysctl_nr_open_min, sysctl_nr_open_max;
-#ifndef CONFIG_MMU
-extern int sysctl_nr_trim_pages;
-#endif
-
 /* Constants used for minimum and  maximum */
 #ifdef CONFIG_LOCKUP_DETECTOR
 static int sixty = 60;
@@ -160,24 +147,6 @@  static unsigned long hung_task_timeout_max = (LONG_MAX/HZ);
 #ifdef CONFIG_INOTIFY_USER
 #include <linux/inotify.h>
 #endif
-#ifdef CONFIG_SPARC
-#endif
-
-#ifdef CONFIG_PARISC
-extern int pwrsw_enabled;
-#endif
-
-#ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
-extern int unaligned_enabled;
-#endif
-
-#ifdef CONFIG_IA64
-extern int unaligned_dump_stack;
-#endif
-
-#ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
-extern int no_unaligned_warning;
-#endif
 
 #ifdef CONFIG_PROC_SYSCTL
 
@@ -243,14 +212,6 @@  static struct ctl_table vm_table[];
 static struct ctl_table fs_table[];
 static struct ctl_table debug_table[];
 static struct ctl_table dev_table[];
-extern struct ctl_table random_table[];
-#ifdef CONFIG_EPOLL
-extern struct ctl_table epoll_table[];
-#endif
-
-#ifdef CONFIG_FW_LOADER_USER_HELPER
-extern struct ctl_table firmware_config_table[];
-#endif
 
 #if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
     defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)