Detach sched.h from mm.h

First thing mm.h does is including sched.h solely for can_do_mlock() inline
function which has "current" dereference inside. By dealing with can_do_mlock()
mm.h can be detached from sched.h which is good. See below, why.

This patch
a) removes unconditional inclusion of sched.h from mm.h
b) makes can_do_mlock() normal function in mm/mlock.c
c) exports can_do_mlock() to not break compilation
d) adds sched.h inclusions back to files that were getting it indirectly.
e) adds less bloated headers to some files (asm/signal.h, jiffies.h) that were
   getting them indirectly

Net result is:
a) mm.h users would get less code to open, read, preprocess, parse, ... if
   they don't need sched.h
b) sched.h stops being dependency for significant number of files:
   on x86_64 allmodconfig touching sched.h results in recompile of 4083 files,
   after patch it's only 3744 (-8.3%).

Cross-compile tested on

	all arm defconfigs, all mips defconfigs, all powerpc defconfigs,
	alpha alpha-up
	arm
	i386 i386-up i386-defconfig i386-allnoconfig
	ia64 ia64-up
	m68k
	mips
	parisc parisc-up
	powerpc powerpc-up
	s390 s390-up
	sparc sparc-up
	sparc64 sparc64-up
	um-x86_64
	x86_64 x86_64-up x86_64-defconfig x86_64-allnoconfig

as well as my two usual configs.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

13 files changed, 18 insertions, 9 deletions

diff --git a/include/asm-arm/tlbflush.h b/include/asm-arm/tlbflush.h
index 08c6991dc9c9..ccd0de010e81 100644
--- a/include/asm-arm/tlbflush.h
+++ b/include/asm-arm/tlbflush.h
@@ -144,6 +144,8 @@
 
 #ifndef __ASSEMBLY__
 
+#include <linux/sched.h>
+
 struct cpu_tlb_fns {
         void (*flush_user_range)(unsigned long, unsigned long, struct vm_area_struct *);
         void (*flush_kern_range)(unsigned long, unsigned long);
diff --git a/include/asm-i386/tlbflush.h b/include/asm-i386/tlbflush.h
index db7f77eacfa0..fc525c5cd5a9 100644
--- a/include/asm-i386/tlbflush.h
+++ b/include/asm-i386/tlbflush.h
@@ -90,6 +90,8 @@
 
 #ifndef CONFIG_SMP
 
+#include <linux/sched.h>
+
 #define flush_tlb() __flush_tlb()
 #define flush_tlb_all() __flush_tlb_all()
 #define local_flush_tlb() __flush_tlb()
diff --git a/include/asm-mips/pgalloc.h b/include/asm-mips/pgalloc.h
index 5685d4fc7881..9fb57c035213 100644
--- a/include/asm-mips/pgalloc.h
+++ b/include/asm-mips/pgalloc.h
@@ -11,6 +11,7 @@
 
 #include <linux/highmem.h>
 #include <linux/mm.h>
+#include <linux/sched.h>
 
 static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd,
         pte_t *pte)
diff --git a/include/asm-parisc/mmu_context.h b/include/asm-parisc/mmu_context.h
index bad690298f0c..85856c74ad1d 100644
--- a/include/asm-parisc/mmu_context.h
+++ b/include/asm-parisc/mmu_context.h
@@ -2,6 +2,7 @@
 #define __PARISC_MMU_CONTEXT_H
 
 #include <linux/mm.h>
+#include <linux/sched.h>
 #include <asm/atomic.h>
 #include <asm/pgalloc.h>
 #include <asm/pgtable.h>
diff --git a/include/asm-parisc/tlbflush.h b/include/asm-parisc/tlbflush.h
index 3313da9ea00f..270cf309772b 100644
--- a/include/asm-parisc/tlbflush.h
+++ b/include/asm-parisc/tlbflush.h
@@ -4,6 +4,7 @@
 /* TLB flushing routines.... */
 
 #include <linux/mm.h>
+#include <linux/sched.h>
 #include <asm/mmu_context.h>
 
 
diff --git a/include/asm-powerpc/mmu_context.h b/include/asm-powerpc/mmu_context.h
index c0d7795e3d25..40c9e5a13ff1 100644
--- a/include/asm-powerpc/mmu_context.h
+++ b/include/asm-powerpc/mmu_context.h
@@ -8,6 +8,7 @@
 
 #include <linux/kernel.h>       
 #include <linux/mm.h>   
+#include <linux/sched.h>
 #include <asm/mmu.h>    
 #include <asm/cputable.h>
 #include <asm-generic/mm_hooks.h>
diff --git a/include/asm-x86_64/calgary.h b/include/asm-x86_64/calgary.h
index 7ee900645719..4d5747a0923c 100644
--- a/include/asm-x86_64/calgary.h
+++ b/include/asm-x86_64/calgary.h
@@ -27,6 +27,7 @@
 #include <linux/spinlock.h>
 #include <linux/device.h>
 #include <linux/dma-mapping.h>
+#include <linux/timer.h>
 #include <asm/types.h>
 
 struct iommu_table {
diff --git a/include/asm-x86_64/tlbflush.h b/include/asm-x86_64/tlbflush.h
index 512401b8725f..8516225a8389 100644
--- a/include/asm-x86_64/tlbflush.h
+++ b/include/asm-x86_64/tlbflush.h
@@ -2,6 +2,7 @@
 #define _X8664_TLBFLUSH_H
 
 #include <linux/mm.h>
+#include <linux/sched.h>
 #include <asm/processor.h>
 #include <asm/system.h>
 
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 4670ebd1f622..e4183c6c7de3 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1,7 +1,6 @@
 #ifndef _LINUX_MM_H
 #define _LINUX_MM_H
 
-#include <linux/sched.h>
 #include <linux/errno.h>
 #include <linux/capability.h>
 
@@ -20,6 +19,7 @@
 
 struct mempolicy;
 struct anon_vma;
+struct user_struct;
 
 #ifndef CONFIG_DISCONTIGMEM          /* Don't use mapnrs, do it properly */
 extern unsigned long max_mapnr;
@@ -717,14 +717,7 @@ extern unsigned long shmem_get_unmapped_area(struct file *file,
                                              unsigned long flags);
 #endif
 
-static inline int can_do_mlock(void)
-{
-        if (capable(CAP_IPC_LOCK))
-                return 1;
-        if (current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur != 0)
-                return 1;
-        return 0;
-}
+extern int can_do_mlock(void);
 extern int user_shm_lock(size_t, struct user_struct *);
 extern void user_shm_unlock(size_t, struct user_struct *);
 
diff --git a/include/linux/smb_fs.h b/include/linux/smb_fs.h
index 13b3af547864..6b51a48e8995 100644
--- a/include/linux/smb_fs.h
+++ b/include/linux/smb_fs.h
@@ -9,6 +9,7 @@
 #ifndef _LINUX_SMB_FS_H
 #define _LINUX_SMB_FS_H
 
+#include <linux/jiffies.h>
 #include <linux/smb.h>
 
 /*
diff --git a/include/linux/task_io_accounting_ops.h b/include/linux/task_io_accounting_ops.h
index 1218733ec6b5..ff46c6fad79d 100644
--- a/include/linux/task_io_accounting_ops.h
+++ b/include/linux/task_io_accounting_ops.h
@@ -4,6 +4,8 @@
 #ifndef __TASK_IO_ACCOUNTING_OPS_INCLUDED
 #define __TASK_IO_ACCOUNTING_OPS_INCLUDED
 
+#include <linux/sched.h>
+
 #ifdef CONFIG_TASK_IO_ACCOUNTING
 static inline void task_io_account_read(size_t bytes)
 {
diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index 050915b59576..4ef4d22e5e43 100644
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -4,6 +4,8 @@
 #ifndef WRITEBACK_H
 #define WRITEBACK_H
 
+#include <linux/sched.h>
+
 struct backing_dev_info;
 
 extern spinlock_t inode_lock;
diff --git a/include/rdma/ib_umem.h b/include/rdma/ib_umem.h
index b3a36f7d79e5..c533d6c7903f 100644
--- a/include/rdma/ib_umem.h
+++ b/include/rdma/ib_umem.h
@@ -35,6 +35,7 @@
 
 #include <linux/list.h>
 #include <linux/scatterlist.h>
+#include <linux/workqueue.h>
 
 struct ib_ucontext;