From 3f96b79ad96263cc0ece7bb340cddf9b2ddfb1b3 Mon Sep 17 00:00:00 2001
From: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Date: Mon, 21 Sep 2009 17:03:37 -0700
Subject: [PATCH] tmpfs: depend on shmem
CONFIG_SHMEM off gives you (ramfs masquerading as) tmpfs, even when
CONFIG_TMPFS is off: that's a little anomalous, and I'd intended to make
more sense of it by removing CONFIG_TMPFS altogether, always enabling its
code when CONFIG_SHMEM; but so many defconfigs have CONFIG_SHMEM on
CONFIG_TMPFS off that we'd better leave that as is.
But there is no point in asking for CONFIG_TMPFS if CONFIG_SHMEM is off:
make TMPFS depend on SHMEM, which also prevents TMPFS_POSIX_ACL
shmem_acl.o being pointlessly built into the kernel when SHMEM is off.
And a selfish change, to prevent the world from being rebuilt when I
switch between CONFIG_SHMEM on and off: the only CONFIG_SHMEM in the
header files is mm.h shmem_lock() - give that a shmem.c stub instead.
Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Acked-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
fs/Kconfig | 1 +
include/linux/mm.h | 11 +----------
mm/shmem.c | 5 +++++
3 files changed, 7 insertions(+), 10 deletions(-)
diff --git a/fs/Kconfig b/fs/Kconfig
index 455aa207e67e8..d4bf8caad8d08 100644
--- a/fs/Kconfig
+++ b/fs/Kconfig
@@ -109,6 +109,7 @@ source "fs/sysfs/Kconfig"
config TMPFS
bool "Virtual memory file system support (former shm fs)"
+ depends on SHMEM
help
Tmpfs is a file system which keeps all files in virtual memory.
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 5409eced7aae0..5946e2ff9fe81 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -702,17 +702,8 @@ extern void pagefault_out_of_memory(void);
extern void show_free_areas(void);
-#ifdef CONFIG_SHMEM
-extern int shmem_lock(struct file *file, int lock, struct user_struct *user);
-#else
-static inline int shmem_lock(struct file *file, int lock,
- struct user_struct *user)
-{
- return 0;
-}
-#endif
+int shmem_lock(struct file *file, int lock, struct user_struct *user);
struct file *shmem_file_setup(const char *name, loff_t size, unsigned long flags);
-
int shmem_zero_setup(struct vm_area_struct *);
#ifndef CONFIG_MMU
diff --git a/mm/shmem.c b/mm/shmem.c
index 25ba75d025808..b4b56fd1e7728 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -2593,6 +2593,11 @@ int shmem_unuse(swp_entry_t entry, struct page *page)
return 0;
}
+int shmem_lock(struct file *file, int lock, struct user_struct *user)
+{
+ return 0;
+}
+
#define shmem_vm_ops generic_file_vm_ops
#define shmem_file_operations ramfs_file_operations
#define shmem_get_inode(sb, mode, dev, flags) ramfs_get_inode(sb, mode, dev)
--
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