untangle the do_mremap() mess

This backports the following upstream commits all as one patch:
	54f5de709984bae0d31d823ff03de755f9dcac54
	ecc1a8993751de4e82eb18640d631dae1f626bd6
	1a0ef85f84feb13f07b604fcf5b90ef7c2b5c82f
	f106af4e90eadd76cfc0b5325f659619e08fb762
	097eed103862f9c6a97f2e415e21d1134017b135
	935874141df839c706cd6cdc438e85eb69d1525e
	0ec62d290912bb4b989be7563851bc364ec73b56
	c4caa778157dbbf04116f0ac2111e389b5cd7a29
	2ea1d13f64efdf49319e86c87d9ba38c30902782
	570dcf2c15463842e384eb597a87c1e39bead99b
	564b3bffc619dcbdd160de597b0547a7017ea010
	0067bd8a55862ac9dd212bd1c4f6f5bff1ca1301
	f8b7256096a20436f6d0926747e3ac3d64c81d24
	8c7b49b3ecd48923eb64ff57e07a1cdb74782970
	9206de95b1ea68357996ec02be5db0638a0de2c1
	2c6a10161d0b5fc047b5bd81b03693b9af99fab5
	05d72faa6d13c9d857478a5d35c85db9adada685
	bb52d6694002b9d632bb355f64daa045c6293a4e
	e77414e0aad6a1b063ba5e5750c582c75327ea6a
	aa65607373a4daf2010e8c3867b6317619f3c1a3

Backport done by Greg Kroah-Hartman.  Only minor tweaks were needed.

Cc: David S. Miller <davem@davemloft.net>
Cc: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

58 files changed, 342 insertions, 1179 deletions

diff --git a/arch/alpha/kernel/osf_sys.c b/arch/alpha/kernel/osf_sys.c
index 9a3334ae282..62619f25132 100644
--- a/arch/alpha/kernel/osf_sys.c
+++ b/arch/alpha/kernel/osf_sys.c
@@ -178,25 +178,18 @@ SYSCALL_DEFINE6(osf_mmap, unsigned long, addr, unsigned long, len,
 		unsigned long, prot, unsigned long, flags, unsigned long, fd,
 		unsigned long, off)
 {
-	struct file *file = NULL;
-	unsigned long ret = -EBADF;
+	unsigned long ret = -EINVAL;
 
 #if 0
 	if (flags & (_MAP_HASSEMAPHORE | _MAP_INHERIT | _MAP_UNALIGNED))
 		printk("%s: unimplemented OSF mmap flags %04lx\n", 
 			current->comm, flags);
 #endif
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	down_write(&current->mm->mmap_sem);
-	ret = do_mmap(file, addr, len, prot, flags, off);
-	up_write(&current->mm->mmap_sem);
-	if (file)
-		fput(file);
+	if ((off + PAGE_ALIGN(len)) < off)
+		goto out;
+	if (off & ~PAGE_MASK)
+		goto out;
+	ret = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
  out:
 	return ret;
 }
diff --git a/arch/arm/include/asm/mman.h b/arch/arm/include/asm/mman.h
index 8eebf89f5ab..41f99c573b9 100644
--- a/arch/arm/include/asm/mman.h
+++ b/arch/arm/include/asm/mman.h
@@ -1 +1,4 @@
 #include <asm-generic/mman.h>
+
+#define arch_mmap_check(addr, len, flags) \
+	(((flags) & MAP_FIXED && (addr) < FIRST_USER_ADDRESS) ? -EINVAL : 0)
diff --git a/arch/arm/kernel/calls.S b/arch/arm/kernel/calls.S
index fafce1b5c69..4f07168cf33 100644
--- a/arch/arm/kernel/calls.S
+++ b/arch/arm/kernel/calls.S
@@ -172,7 +172,7 @@
 /* 160 */	CALL(sys_sched_get_priority_min)
 		CALL(sys_sched_rr_get_interval)
 		CALL(sys_nanosleep)
-		CALL(sys_arm_mremap)
+		CALL(sys_mremap)
 		CALL(sys_setresuid16)
 /* 165 */	CALL(sys_getresuid16)
 		CALL(sys_ni_syscall)		/* vm86 */
diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index f0fe95b7085..2c1db77d784 100644
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -416,12 +416,12 @@ sys_mmap2:
 		tst	r5, #PGOFF_MASK
 		moveq	r5, r5, lsr #PAGE_SHIFT - 12
 		streq	r5, [sp, #4]
-		beq	do_mmap2
+		beq	sys_mmap_pgoff
 		mov	r0, #-EINVAL
 		mov	pc, lr
 #else
 		str	r5, [sp, #4]
-		b	do_mmap2
+		b	sys_mmap_pgoff
 #endif
 ENDPROC(sys_mmap2)
 
diff --git a/arch/arm/kernel/sys_arm.c b/arch/arm/kernel/sys_arm.c
index 78ecaac6520..ae4027bd01b 100644
--- a/arch/arm/kernel/sys_arm.c
+++ b/arch/arm/kernel/sys_arm.c
@@ -28,41 +28,6 @@
 #include <linux/ipc.h>
 #include <linux/uaccess.h>
 
-extern unsigned long do_mremap(unsigned long addr, unsigned long old_len,
-			       unsigned long new_len, unsigned long flags,
-			       unsigned long new_addr);
-
-/* common code for old and new mmaps */
-inline long do_mmap2(
-	unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags,
-	unsigned long fd, unsigned long pgoff)
-{
-	int error = -EINVAL;
-	struct file * file = NULL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-
-	if (flags & MAP_FIXED && addr < FIRST_USER_ADDRESS)
-		goto out;
-
-	error = -EBADF;
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-out:
-	return error;
-}
-
 struct mmap_arg_struct {
 	unsigned long addr;
 	unsigned long len;
@@ -84,29 +49,11 @@ asmlinkage int old_mmap(struct mmap_arg_struct __user *arg)
 	if (a.offset & ~PAGE_MASK)
 		goto out;
 
-	error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
+	error = sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
 out:
 	return error;
 }
 
-asmlinkage unsigned long
-sys_arm_mremap(unsigned long addr, unsigned long old_len,
-	       unsigned long new_len, unsigned long flags,
-	       unsigned long new_addr)
-{
-	unsigned long ret = -EINVAL;
-
-	if (flags & MREMAP_FIXED && new_addr < FIRST_USER_ADDRESS)
-		goto out;
-
-	down_write(&current->mm->mmap_sem);
-	ret = do_mremap(addr, old_len, new_len, flags, new_addr);
-	up_write(&current->mm->mmap_sem);
-
-out:
-	return ret;
-}
-
 /*
  * Perform the select(nd, in, out, ex, tv) and mmap() system
  * calls.
diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c
index 2b7996401b0..f5abc51c5a0 100644
--- a/arch/arm/mm/mmap.c
+++ b/arch/arm/mm/mmap.c
@@ -54,7 +54,8 @@ arch_get_unmapped_area(struct file *filp, unsigned long addr,
 	 * We enforce the MAP_FIXED case.
 	 */
 	if (flags & MAP_FIXED) {
-		if (aliasing && flags & MAP_SHARED && addr & (SHMLBA - 1))
+		if (aliasing && flags & MAP_SHARED &&
+		    (addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1))
 			return -EINVAL;
 		return addr;
 	}
diff --git a/arch/avr32/include/asm/syscalls.h b/arch/avr32/include/asm/syscalls.h
index 483d666c27c..66a19726663 100644
--- a/arch/avr32/include/asm/syscalls.h
+++ b/arch/avr32/include/asm/syscalls.h
@@ -29,10 +29,6 @@ asmlinkage int sys_sigaltstack(const stack_t __user *, stack_t __user *,
 			       struct pt_regs *);
 asmlinkage int sys_rt_sigreturn(struct pt_regs *);
 
-/* kernel/sys_avr32.c */
-asmlinkage long sys_mmap2(unsigned long, unsigned long, unsigned long,
-			  unsigned long, unsigned long, off_t);
-
 /* mm/cache.c */
 asmlinkage int sys_cacheflush(int, void __user *, size_t);
 
diff --git a/arch/avr32/kernel/sys_avr32.c b/arch/avr32/kernel/sys_avr32.c
index 5d2daeaf356..459349b5ed5 100644
--- a/arch/avr32/kernel/sys_avr32.c
+++ b/arch/avr32/kernel/sys_avr32.c
@@ -5,39 +5,8 @@
  * it under the terms of the GNU General Public License version 2 as
  * published by the Free Software Foundation.
  */
-#include <linux/errno.h>
-#include <linux/fs.h>
-#include <linux/file.h>
-#include <linux/mm.h>
 #include <linux/unistd.h>
 
-#include <asm/mman.h>
-#include <asm/uaccess.h>
-#include <asm/syscalls.h>
-
-asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
-			  unsigned long prot, unsigned long flags,
-			  unsigned long fd, off_t offset)
-{
-	int error = -EBADF;
-	struct file *file = NULL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			return error;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, offset);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-	return error;
-}
-
 int kernel_execve(const char *file, char **argv, char **envp)
 {
 	register long scno asm("r8") = __NR_execve;
diff --git a/arch/avr32/kernel/syscall-stubs.S b/arch/avr32/kernel/syscall-stubs.S
index f7244cd02fb..0447a3e2ba6 100644
--- a/arch/avr32/kernel/syscall-stubs.S
+++ b/arch/avr32/kernel/syscall-stubs.S
@@ -61,7 +61,7 @@ __sys_execve:
 __sys_mmap2:
 	pushm	lr
 	st.w	--sp, ARG6
-	call	sys_mmap2
+	call	sys_mmap_pgoff
 	sub	sp, -4
 	popm	pc
 
diff --git a/arch/blackfin/kernel/sys_bfin.c b/arch/blackfin/kernel/sys_bfin.c
index afcef129d4e..2e7f8e10bf8 100644
--- a/arch/blackfin/kernel/sys_bfin.c
+++ b/arch/blackfin/kernel/sys_bfin.c
@@ -22,39 +22,6 @@
 #include <asm/cacheflush.h>
 #include <asm/dma.h>
 
-/* common code for old and new mmaps */
-static inline long
-do_mmap2(unsigned long addr, unsigned long len,
-	 unsigned long prot, unsigned long flags,
-	 unsigned long fd, unsigned long pgoff)
-{
-	int error = -EBADF;
-	struct file *file = NULL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
- out:
-	return error;
-}
-
-asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
-			  unsigned long prot, unsigned long flags,
-			  unsigned long fd, unsigned long pgoff)
-{
-	return do_mmap2(addr, len, prot, flags, fd, pgoff);
-}
-
 asmlinkage void *sys_sram_alloc(size_t size, unsigned long flags)
 {
 	return sram_alloc_with_lsl(size, flags);
diff --git a/arch/blackfin/mach-common/entry.S b/arch/blackfin/mach-common/entry.S
index 94a0375cbdc..1d8f00ab9ee 100644
--- a/arch/blackfin/mach-common/entry.S
+++ b/arch/blackfin/mach-common/entry.S
@@ -1422,7 +1422,7 @@ ENTRY(_sys_call_table)
 	.long _sys_ni_syscall	/* streams2 */
 	.long _sys_vfork		/* 190 */
 	.long _sys_getrlimit
-	.long _sys_mmap2
+	.long _sys_mmap_pgoff
 	.long _sys_truncate64
 	.long _sys_ftruncate64
 	.long _sys_stat64	/* 195 */
diff --git a/arch/cris/kernel/sys_cris.c b/arch/cris/kernel/sys_cris.c
index 2ad962c7e88..c2bbb1ac98a 100644
--- a/arch/cris/kernel/sys_cris.c
+++ b/arch/cris/kernel/sys_cris.c
@@ -26,31 +26,6 @@
 #include <asm/uaccess.h>
 #include <asm/segment.h>
 
-/* common code for old and new mmaps */
-static inline long
-do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
-        unsigned long flags, unsigned long fd, unsigned long pgoff)
-{
-        int error = -EBADF;
-        struct file * file = NULL;
-
-        flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-        if (!(flags & MAP_ANONYMOUS)) {
-                file = fget(fd);
-                if (!file)
-                        goto out;
-        }
-
-        down_write(&current->mm->mmap_sem);
-        error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-        up_write(&current->mm->mmap_sem);
-
-        if (file)
-                fput(file);
-out:
-        return error;
-}
-
 asmlinkage unsigned long old_mmap(unsigned long __user *args)
 {        
 	unsigned long buffer[6];
@@ -63,7 +38,7 @@ asmlinkage unsigned long old_mmap(unsigned long __user *args)
 	if (buffer[5] & ~PAGE_MASK) /* verify that offset is on page boundary */
 		goto out;
 
-	err = do_mmap2(buffer[0], buffer[1], buffer[2], buffer[3],
+	err = sys_mmap_pgoff(buffer[0], buffer[1], buffer[2], buffer[3],
                        buffer[4], buffer[5] >> PAGE_SHIFT);
 out:
 	return err;
@@ -73,7 +48,8 @@ asmlinkage long
 sys_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
           unsigned long flags, unsigned long fd, unsigned long pgoff)
 {
-        return do_mmap2(addr, len, prot, flags, fd, pgoff);
+	/* bug(?): 8Kb pages here */
+        return sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);
 }
 
 /*
diff --git a/arch/frv/kernel/sys_frv.c b/arch/frv/kernel/sys_frv.c
index 2b6b5289cdc..1d3d4c9e252 100644
--- a/arch/frv/kernel/sys_frv.c
+++ b/arch/frv/kernel/sys_frv.c
@@ -31,9 +31,6 @@ asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
 			  unsigned long prot, unsigned long flags,
 			  unsigned long fd, unsigned long pgoff)
 {
-	int error = -EBADF;
-	struct file * file = NULL;
-
 	/* As with sparc32, make sure the shift for mmap2 is constant
 	   (12), no matter what PAGE_SIZE we have.... */
 
@@ -41,69 +38,10 @@ asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
 	   trying to map something we can't */
 	if (pgoff & ((1 << (PAGE_SHIFT - 12)) - 1))
 		return -EINVAL;
-	pgoff >>= PAGE_SHIFT - 12;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-out:
-	return error;
-}
-
-#if 0 /* DAVIDM - do we want this */
-struct mmap_arg_struct64 {
-	__u32 addr;
-	__u32 len;
-	__u32 prot;
-	__u32 flags;
-	__u64 offset; /* 64 bits */
-	__u32 fd;
-};
-
-asmlinkage long sys_mmap64(struct mmap_arg_struct64 *arg)
-{
-	int error = -EFAULT;
-	struct file * file = NULL;
-	struct mmap_arg_struct64 a;
-	unsigned long pgoff;
-
-	if (copy_from_user(&a, arg, sizeof(a)))
-		return -EFAULT;
-
-	if ((long)a.offset & ~PAGE_MASK)
-		return -EINVAL;
-
-	pgoff = a.offset >> PAGE_SHIFT;
-	if ((a.offset >> PAGE_SHIFT) != pgoff)
-		return -EINVAL;
-
-	if (!(a.flags & MAP_ANONYMOUS)) {
-		error = -EBADF;
-		file = fget(a.fd);
-		if (!file)
-			goto out;
-	}
-	a.flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, a.addr, a.len, a.prot, a.flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-	if (file)
-		fput(file);
-out:
-	return error;
+	return sys_mmap_pgoff(addr, len, prot, flags, fd,
+			      pgoff >> (PAGE_SHIFT - 12));
 }
-#endif
 
 /*
  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
diff --git a/arch/h8300/kernel/sys_h8300.c b/arch/h8300/kernel/sys_h8300.c
index 8cb5d73a0e3..b5969db0ca1 100644
--- a/arch/h8300/kernel/sys_h8300.c
+++ b/arch/h8300/kernel/sys_h8300.c
@@ -26,39 +26,6 @@
 #include <asm/traps.h>
 #include <asm/unistd.h>
 
-/* common code for old and new mmaps */
-static inline long do_mmap2(
-	unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags,
-	unsigned long fd, unsigned long pgoff)
-{
-	int error = -EBADF;
-	struct file * file = NULL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-out:
-	return error;
-}
-
-asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags,
-	unsigned long fd, unsigned long pgoff)
-{
-	return do_mmap2(addr, len, prot, flags, fd, pgoff);
-}
-
 /*
  * Perform the select(nd, in, out, ex, tv) and mmap() system
  * calls. Linux/m68k cloned Linux/i386, which didn't use to be able to
@@ -87,57 +54,11 @@ asmlinkage int old_mmap(struct mmap_arg_struct *arg)
 	if (a.offset & ~PAGE_MASK)
 		goto out;
 
-	a.flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-
-	error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
-out:
-	return error;
-}
-
-#if 0 /* DAVIDM - do we want this */
-struct mmap_arg_struct64 {
-	__u32 addr;
-	__u32 len;
-	__u32 prot;
-	__u32 flags;
-	__u64 offset; /* 64 bits */
-	__u32 fd;
-};
-
-asmlinkage long sys_mmap64(struct mmap_arg_struct64 *arg)
-{
-	int error = -EFAULT;
-	struct file * file = NULL;
-	struct mmap_arg_struct64 a;
-	unsigned long pgoff;
-
-	if (copy_from_user(&a, arg, sizeof(a)))
-		return -EFAULT;
-
-	if ((long)a.offset & ~PAGE_MASK)
-		return -EINVAL;
-
-	pgoff = a.offset >> PAGE_SHIFT;
-	if ((a.offset >> PAGE_SHIFT) != pgoff)
-		return -EINVAL;
-
-	if (!(a.flags & MAP_ANONYMOUS)) {
-		error = -EBADF;
-		file = fget(a.fd);
-		if (!file)
-			goto out;
-	}
-	a.flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, a.addr, a.len, a.prot, a.flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-	if (file)
-		fput(file);
+	error = sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
+			       a.offset >> PAGE_SHIFT);
 out:
 	return error;
 }
-#endif
 
 struct sel_arg_struct {
 	unsigned long n;
diff --git a/arch/h8300/kernel/syscalls.S b/arch/h8300/kernel/syscalls.S
index 4eb67faac63..2d69881eda6 100644
--- a/arch/h8300/kernel/syscalls.S
+++ b/arch/h8300/kernel/syscalls.S
@@ -206,7 +206,7 @@ SYMBOL_NAME_LABEL(sys_call_table)
 	.long SYMBOL_NAME(sys_ni_syscall)	/* streams2 */
 	.long SYMBOL_NAME(sys_vfork)            /* 190 */
 	.long SYMBOL_NAME(sys_getrlimit)
-	.long SYMBOL_NAME(sys_mmap2)
+	.long SYMBOL_NAME(sys_mmap_pgoff)
 	.long SYMBOL_NAME(sys_truncate64)
 	.long SYMBOL_NAME(sys_ftruncate64)
 	.long SYMBOL_NAME(sys_stat64)		/* 195 */
diff --git a/arch/ia64/ia32/sys_ia32.c b/arch/ia64/ia32/sys_ia32.c
index 625ed8f76fc..e031ee8ecb0 100644
--- a/arch/ia64/ia32/sys_ia32.c
+++ b/arch/ia64/ia32/sys_ia32.c
@@ -858,6 +858,9 @@ ia32_do_mmap (struct file *file, unsigned long addr, unsigned long len, int prot
 
 	prot = get_prot32(prot);
 
+	if (flags & MAP_HUGETLB)
+		return -ENOMEM;
+
 #if PAGE_SHIFT > IA32_PAGE_SHIFT
 	mutex_lock(&ia32_mmap_mutex);
 	{
diff --git a/arch/ia64/kernel/sys_ia64.c b/arch/ia64/kernel/sys_ia64.c
index 92ed83f3403..609d50056a6 100644
--- a/arch/ia64/kernel/sys_ia64.c
+++ b/arch/ia64/kernel/sys_ia64.c
@@ -100,51 +100,7 @@ sys_getpagesize (void)
 asmlinkage unsigned long
 ia64_brk (unsigned long brk)
 {
-	unsigned long rlim, retval, newbrk, oldbrk;
-	struct mm_struct *mm = current->mm;
-
-	/*
-	 * Most of this replicates the code in sys_brk() except for an additional safety
-	 * check and the clearing of r8.  However, we can't call sys_brk() because we need
-	 * to acquire the mmap_sem before we can do the test...
-	 */
-	down_write(&mm->mmap_sem);
-
-	if (brk < mm->end_code)
-		goto out;
-	newbrk = PAGE_ALIGN(brk);
-	oldbrk = PAGE_ALIGN(mm->brk);
-	if (oldbrk == newbrk)
-		goto set_brk;
-
-	/* Always allow shrinking brk. */
-	if (brk <= mm->brk) {
-		if (!do_munmap(mm, newbrk, oldbrk-newbrk))
-			goto set_brk;
-		goto out;
-	}
-
-	/* Check against unimplemented/unmapped addresses: */
-	if ((newbrk - oldbrk) > RGN_MAP_LIMIT || REGION_OFFSET(newbrk) > RGN_MAP_LIMIT)
-		goto out;
-
-	/* Check against rlimit.. */
-	rlim = current->signal->rlim[RLIMIT_DATA].rlim_cur;
-	if (rlim < RLIM_INFINITY && brk - mm->start_data > rlim)
-		goto out;
-
-	/* Check against existing mmap mappings. */
-	if (find_vma_intersection(mm, oldbrk, newbrk+PAGE_SIZE))
-		goto out;
-
-	/* Ok, looks good - let it rip. */
-	if (do_brk(oldbrk, newbrk-oldbrk) != oldbrk)
-		goto out;
-set_brk:
-	mm->brk = brk;
-out:
-	retval = mm->brk;
-	up_write(&mm->mmap_sem);
+	unsigned long retval = sys_brk(brk);
 	force_successful_syscall_return();
 	return retval;
 }
@@ -185,39 +141,6 @@ int ia64_mmap_check(unsigned long addr, unsigned long len,
 	return 0;
 }
 
-static inline unsigned long
-do_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, unsigned long pgoff)
-{
-	struct file *file = NULL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			return -EBADF;
-
-		if (!file->f_op || !file->f_op->mmap) {
-			addr = -ENODEV;
-			goto out;
-		}
-	}
-
-	/* Careful about overflows.. */
-	len = PAGE_ALIGN(len);
-	if (!len || len > TASK_SIZE) {
-		addr = -EINVAL;
-		goto out;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	addr = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-out:	if (file)
-		fput(file);
-	return addr;
-}
-
 /*
  * mmap2() is like mmap() except that the offset is expressed in units
  * of PAGE_SIZE (instead of bytes).  This allows to mmap2() (pieces
@@ -226,7 +149,7 @@ out:	if (file)
 asmlinkage unsigned long
 sys_mmap2 (unsigned long addr, unsigned long len, int prot, int flags, int fd, long pgoff)
 {
-	addr = do_mmap2(addr, len, prot, flags, fd, pgoff);
+	addr = sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);
 	if (!IS_ERR((void *) addr))
 		force_successful_syscall_return();
 	return addr;
@@ -238,7 +161,7 @@ sys_mmap (unsigned long addr, unsigned long len, int prot, int flags, int fd, lo
 	if (offset_in_page(off) != 0)
 		return -EINVAL;
 
-	addr = do_mmap2(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
+	addr = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
 	if (!IS_ERR((void *) addr))
 		force_successful_syscall_return();
 	return addr;
diff --git a/arch/m32r/kernel/sys_m32r.c b/arch/m32r/kernel/sys_m32r.c
index 305ac852bbe..d3c865c5a6b 100644
--- a/arch/m32r/kernel/sys_m32r.c
+++ b/arch/m32r/kernel/sys_m32r.c
@@ -76,30 +76,6 @@ asmlinkage int sys_tas(int __user *addr)
 	return oldval;
 }
 
-asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags,
-	unsigned long fd, unsigned long pgoff)
-{
-	int error = -EBADF;
-	struct file *file = NULL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-out:
-	return error;
-}
-
 /*
  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
  *
diff --git a/arch/m32r/kernel/syscall_table.S b/arch/m32r/kernel/syscall_table.S
index aa3bf4cfab3..60536e27123 100644
--- a/arch/m32r/kernel/syscall_table.S
+++ b/arch/m32r/kernel/syscall_table.S
@@ -191,7 +191,7 @@ ENTRY(sys_call_table)
 	.long sys_ni_syscall		/* streams2 */
 	.long sys_vfork			/* 190 */
 	.long sys_getrlimit
-	.long sys_mmap2
+	.long sys_mmap_pgoff
 	.long sys_truncate64
 	.long sys_ftruncate64
 	.long sys_stat64		/* 195 */
diff --git a/arch/m68k/kernel/sys_m68k.c b/arch/m68k/kernel/sys_m68k.c
index 7deb402bfc7..218f441de66 100644
--- a/arch/m68k/kernel/sys_m68k.c
+++ b/arch/m68k/kernel/sys_m68k.c
@@ -29,37 +29,16 @@
 #include <asm/page.h>
 #include <asm/unistd.h>
 
-/* common code for old and new mmaps */
-static inline long do_mmap2(
-	unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags,
-	unsigned long fd, unsigned long pgoff)
-{
-	int error = -EBADF;
-	struct file * file = NULL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-out:
-	return error;
-}
-
 asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
 	unsigned long prot, unsigned long flags,
 	unsigned long fd, unsigned long pgoff)
 {
-	return do_mmap2(addr, len, prot, flags, fd, pgoff);
+	/*
+	 * This is wrong for sun3 - there PAGE_SIZE is 8Kb,
+	 * so we need to shift the argument down by 1; m68k mmap64(3)
+	 * (in libc) expects the last argument of mmap2 in 4Kb units.
+	 */
+	return sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);
 }
 
 /*
@@ -90,57 +69,11 @@ asmlinkage int old_mmap(struct mmap_arg_struct __user *arg)
 	if (a.offset & ~PAGE_MASK)
 		goto out;
 
-	a.flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-
-	error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
-out:
-	return error;
-}
-
-#if 0
-struct mmap_arg_struct64 {
-	__u32 addr;
-	__u32 len;
-	__u32 prot;
-	__u32 flags;
-	__u64 offset; /* 64 bits */
-	__u32 fd;
-};
-
-asmlinkage long sys_mmap64(struct mmap_arg_struct64 *arg)
-{
-	int error = -EFAULT;
-	struct file * file = NULL;
-	struct mmap_arg_struct64 a;
-	unsigned long pgoff;
-
-	if (copy_from_user(&a, arg, sizeof(a)))
-		return -EFAULT;
-
-	if ((long)a.offset & ~PAGE_MASK)
-		return -EINVAL;
-
-	pgoff = a.offset >> PAGE_SHIFT;
-	if ((a.offset >> PAGE_SHIFT) != pgoff)
-		return -EINVAL;
-
-	if (!(a.flags & MAP_ANONYMOUS)) {
-		error = -EBADF;
-		file = fget(a.fd);
-		if (!file)
-			goto out;
-	}
-	a.flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, a.addr, a.len, a.prot, a.flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-	if (file)
-		fput(file);
+	error = sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
+			       a.offset >> PAGE_SHIFT);
 out:
 	return error;
 }
-#endif
 
 struct sel_arg_struct {
 	unsigned long n;
diff --git a/arch/m68knommu/kernel/sys_m68k.c b/arch/m68knommu/kernel/sys_m68k.c
index efdd090778a..b67cbc735a9 100644
--- a/arch/m68knommu/kernel/sys_m68k.c
+++ b/arch/m68knommu/kernel/sys_m68k.c
@@ -27,39 +27,6 @@
 #include <asm/cacheflush.h>
 #include <asm/unistd.h>
 
-/* common code for old and new mmaps */
-static inline long do_mmap2(
-	unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags,
-	unsigned long fd, unsigned long pgoff)
-{
-	int error = -EBADF;
-	struct file * file = NULL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-out:
-	return error;
-}
-
-asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags,
-	unsigned long fd, unsigned long pgoff)
-{
-	return do_mmap2(addr, len, prot, flags, fd, pgoff);
-}
-
 /*
  * Perform the select(nd, in, out, ex, tv) and mmap() system
  * calls. Linux/m68k cloned Linux/i386, which didn't use to be able to
@@ -88,9 +55,8 @@ asmlinkage int old_mmap(struct mmap_arg_struct *arg)
 	if (a.offset & ~PAGE_MASK)
 		goto out;
 
-	a.flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-
-	error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
+	error = sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
+				a.offset >> PAGE_SHIFT);
 out:
 	return error;
 }
diff --git a/arch/m68knommu/kernel/syscalltable.S b/arch/m68knommu/kernel/syscalltable.S
index 23535cc415a..486837efa3d 100644
--- a/arch/m68knommu/kernel/syscalltable.S
+++ b/arch/m68knommu/kernel/syscalltable.S
@@ -210,7 +210,7 @@ ENTRY(sys_call_table)
 	.long sys_ni_syscall	/* streams2 */
 	.long sys_vfork		/* 190 */
 	.long sys_getrlimit
-	.long sys_mmap2
+	.long sys_mmap_pgoff
 	.long sys_truncate64
 	.long sys_ftruncate64
 	.long sys_stat64	/* 195 */
diff --git a/arch/microblaze/kernel/sys_microblaze.c b/arch/microblaze/kernel/sys_microblaze.c
index 07cabed4b94..9f3c205fb75 100644
--- a/arch/microblaze/kernel/sys_microblaze.c
+++ b/arch/microblaze/kernel/sys_microblaze.c
@@ -62,46 +62,14 @@ out:
 	return error;
 }
 
-asmlinkage long
-sys_mmap2(unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags,
-	unsigned long fd, unsigned long pgoff)
-{
-	struct file *file = NULL;
-	int ret = -EBADF;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file) {
-			printk(KERN_INFO "no fd in mmap\r\n");
-			goto out;
-		}
-	}
-
-	down_write(&current->mm->mmap_sem);
-	ret = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-	if (file)
-		fput(file);
-out:
-	return ret;
-}
-
 asmlinkage long sys_mmap(unsigned long addr, unsigned long len,
 			unsigned long prot, unsigned long flags,
 			unsigned long fd, off_t pgoff)
 {
-	int err = -EINVAL;
-
-	if (pgoff & ~PAGE_MASK) {
-		printk(KERN_INFO "no pagemask in mmap\r\n");
-		goto out;
-	}
+	if (pgoff & ~PAGE_MASK)
+		return -EINVAL;
 
-	err = sys_mmap2(addr, len, prot, flags, fd, pgoff >> PAGE_SHIFT);
-out:
-	return err;
+	return sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff >> PAGE_SHIFT);
 }
 
 /*
diff --git a/arch/microblaze/kernel/syscall_table.S b/arch/microblaze/kernel/syscall_table.S
index ecec1915513..eb50ce5e4e8 100644
--- a/arch/microblaze/kernel/syscall_table.S
+++ b/arch/microblaze/kernel/syscall_table.S
@@ -196,7 +196,7 @@ ENTRY(sys_call_table)
 	.long sys_ni_syscall		/* reserved for streams2 */
 	.long sys_vfork		/* 190 */
 	.long sys_getrlimit
-	.long sys_mmap2			/* mmap2 */
+	.long sys_mmap_pgoff		/* mmap2 */
 	.long sys_truncate64
 	.long sys_ftruncate64
 	.long sys_stat64		/* 195 */
diff --git a/arch/mips/kernel/linux32.c b/arch/mips/kernel/linux32.c
index b77fefaff9d..ea4a74652cf 100644
--- a/arch/mips/kernel/linux32.c
+++ b/arch/mips/kernel/linux32.c
@@ -67,28 +67,13 @@ SYSCALL_DEFINE6(32_mmap2, unsigned long, addr, unsigned long, len,
 	unsigned long, prot, unsigned long, flags, unsigned long, fd,
 	unsigned long, pgoff)
 {
-	struct file * file = NULL;
 	unsigned long error;
 
 	error = -EINVAL;
 	if (pgoff & (~PAGE_MASK >> 12))
 		goto out;
-	pgoff >>= PAGE_SHIFT-12;
-
-	if (!(flags & MAP_ANONYMOUS)) {
-		error = -EBADF;
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-	if (file)
-		fput(file);
-
+	error = sys_mmap_pgoff(addr, len, prot, flags, fd,
+			       pgoff >> (PAGE_SHIFT-12));
 out:
 	return error;
 }
diff --git a/arch/mips/kernel/syscall.c b/arch/mips/kernel/syscall.c
index fe0d7980560..3f7f466190b 100644
--- a/arch/mips/kernel/syscall.c
+++ b/arch/mips/kernel/syscall.c
@@ -93,7 +93,8 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
 		 * We do not accept a shared mapping if it would violate
 		 * cache aliasing constraints.
 		 */
-		if ((flags & MAP_SHARED) && (addr & shm_align_mask))
+		if ((flags & MAP_SHARED) &&
+		    ((addr - (pgoff << PAGE_SHIFT)) & shm_align_mask))
 			return -EINVAL;
 		return addr;
 	}
@@ -129,31 +130,6 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
 	}
 }
 
-/* common code for old and new mmaps */
-static inline unsigned long
-do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
-        unsigned long flags, unsigned long fd, unsigned long pgoff)
-{
-	unsigned long error = -EBADF;
-	struct file * file = NULL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-out:
-	return error;
-}
-
 SYSCALL_DEFINE6(mips_mmap, unsigned long, addr, unsigned long, len,
 	unsigned long, prot, unsigned long, flags, unsigned long,
 	fd, off_t, offset)
@@ -164,7 +140,7 @@ SYSCALL_DEFINE6(mips_mmap, unsigned long, addr, unsigned long, len,
 	if (offset & ~PAGE_MASK)
 		goto out;
 
-	result = do_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
+	result = sys_mmap_pgoff(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
 
 out:
 	return result;
@@ -177,7 +153,7 @@ SYSCALL_DEFINE6(mips_mmap2, unsigned long, addr, unsigned long, len,
 	if (pgoff & (~PAGE_MASK >> 12))
 		return -EINVAL;
 
-	return do_mmap2(addr, len, prot, flags, fd, pgoff >> (PAGE_SHIFT-12));
+	return sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff >> (PAGE_SHIFT-12));
 }
 
 save_static_function(sys_fork);
diff --git a/arch/mn10300/include/asm/mman.h b/arch/mn10300/include/asm/mman.h
index 8eebf89f5ab..db5c53da73c 100644
--- a/arch/mn10300/include/asm/mman.h
+++ b/arch/mn10300/include/asm/mman.h
@@ -1 +1,6 @@
 #include <asm-generic/mman.h>
+
+#define MIN_MAP_ADDR	PAGE_SIZE	/* minimum fixed mmap address */
+
+#define arch_mmap_check(addr, len, flags) \
+	(((flags) & MAP_FIXED && (addr) < MIN_MAP_ADDR) ? -EINVAL : 0)
diff --git a/arch/mn10300/kernel/entry.S b/arch/mn10300/kernel/entry.S
index a94e7ea3faa..c9ee6c009d7 100644
--- a/arch/mn10300/kernel/entry.S
+++ b/arch/mn10300/kernel/entry.S
@@ -578,7 +578,7 @@ ENTRY(sys_call_table)
 	.long sys_ni_syscall	/* reserved for streams2 */
 	.long sys_vfork		/* 190 */
 	.long sys_getrlimit
-	.long sys_mmap2
+	.long sys_mmap_pgoff
 	.long sys_truncate64
 	.long sys_ftruncate64
 	.long sys_stat64	/* 195 */
diff --git a/arch/mn10300/kernel/sys_mn10300.c b/arch/mn10300/kernel/sys_mn10300.c
index 8ca5af00334..17cc6ce04e8 100644
--- a/arch/mn10300/kernel/sys_mn10300.c
+++ b/arch/mn10300/kernel/sys_mn10300.c
@@ -23,47 +23,13 @@
 
 #include <asm/uaccess.h>
 
-#define MIN_MAP_ADDR	PAGE_SIZE	/* minimum fixed mmap address */
-
-/*
- * memory mapping syscall
- */
-asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
-			  unsigned long prot, unsigned long flags,
-			  unsigned long fd, unsigned long pgoff)
-{
-	struct file *file = NULL;
-	long error = -EINVAL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-
-	if (flags & MAP_FIXED && addr < MIN_MAP_ADDR)
-		goto out;
-
-	error = -EBADF;
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-out:
-	return error;
-}
-
 asmlinkage long old_mmap(unsigned long addr, unsigned long len,
 			 unsigned long prot, unsigned long flags,
 			 unsigned long fd, unsigned long offset)
 {
 	if (offset & ~PAGE_MASK)
 		return -EINVAL;
-	return sys_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
+	return sys_mmap_pgoff(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
 }
 
 struct sel_arg_struct {
diff --git a/arch/parisc/kernel/sys_parisc.c b/arch/parisc/kernel/sys_parisc.c
index 71b31957c8f..9147391afb0 100644
--- a/arch/parisc/kernel/sys_parisc.c
+++ b/arch/parisc/kernel/sys_parisc.c
@@ -110,37 +110,14 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
 	return addr;
 }
 
-static unsigned long do_mmap2(unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags, unsigned long fd,
-	unsigned long pgoff)
-{
-	struct file * file = NULL;
-	unsigned long error = -EBADF;
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file != NULL)
-		fput(file);
-out:
-	return error;
-}
-
 asmlinkage unsigned long sys_mmap2(unsigned long addr, unsigned long len,
 	unsigned long prot, unsigned long flags, unsigned long fd,
 	unsigned long pgoff)
 {
 	/* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
 	   we have. */
-	return do_mmap2(addr, len, prot, flags, fd, pgoff >> (PAGE_SHIFT - 12));
+	return sys_mmap_pgoff(addr, len, prot, flags, fd,
+			      pgoff >> (PAGE_SHIFT - 12));
 }
 
 asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len,
@@ -148,7 +125,8 @@ asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len,
 		unsigned long offset)
 {
 	if (!(offset & ~PAGE_MASK)) {
-		return do_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
+		return sys_mmap_pgoff(addr, len, prot, flags, fd,
+					offset >> PAGE_SHIFT);
 	} else {
 		return -EINVAL;
 	}
diff --git a/arch/powerpc/kernel/syscalls.c b/arch/powerpc/kernel/syscalls.c
index c04832c4a02..3370e62e43d 100644
--- a/arch/powerpc/kernel/syscalls.c
+++ b/arch/powerpc/kernel/syscalls.c
@@ -140,7 +140,6 @@ static inline unsigned long do_mmap2(unsigned long addr, size_t len,
 			unsigned long prot, unsigned long flags,
 			unsigned long fd, unsigned long off, int shift)
 {
-	struct file * file = NULL;
 	unsigned long ret = -EINVAL;
 
 	if (!arch_validate_prot(prot))
@@ -151,20 +150,8 @@ static inline unsigned long do_mmap2(unsigned long addr, size_t len,
 			goto out;
 		off >>= shift;
 	}
-		
-	ret = -EBADF;
-	if (!(flags & MAP_ANONYMOUS)) {
-		if (!(file = fget(fd)))
-			goto out;
-	}
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 
-	down_write(&current->mm->mmap_sem);
-	ret = do_mmap_pgoff(file, addr, len, prot, flags, off);
-	up_write(&current->mm->mmap_sem);
-	if (file)
-		fput(file);
+	ret = sys_mmap_pgoff(addr, len, prot, flags, fd, off);
 out:
 	return ret;
 }
diff --git a/arch/s390/kernel/compat_linux.c b/arch/s390/kernel/compat_linux.c
index 0debcec23a3..9c746c01a7a 100644
--- a/arch/s390/kernel/compat_linux.c
+++ b/arch/s390/kernel/compat_linux.c
@@ -683,38 +683,6 @@ struct mmap_arg_struct_emu31 {
 	u32	offset;
 };
 
-/* common code for old and new mmaps */
-static inline long do_mmap2(
-	unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags,
-	unsigned long fd, unsigned long pgoff)
-{
-	struct file * file = NULL;
-	unsigned long error = -EBADF;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	if (!IS_ERR((void *) error) && error + len >= 0x80000000ULL) {
-		/* Result is out of bounds.  */
-		do_munmap(current->mm, addr, len);
-		error = -ENOMEM;
-	}
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-out:    
-	return error;
-}
-
-
 asmlinkage unsigned long
 old32_mmap(struct mmap_arg_struct_emu31 __user *arg)
 {
@@ -728,7 +696,8 @@ old32_mmap(struct mmap_arg_struct_emu31 __user *arg)
 	if (a.offset & ~PAGE_MASK)
 		goto out;
 
-	error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT); 
+	error = sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
+			       a.offset >> PAGE_SHIFT);
 out:
 	return error;
 }
@@ -741,7 +710,7 @@ sys32_mmap2(struct mmap_arg_struct_emu31 __user *arg)
 
 	if (copy_from_user(&a, arg, sizeof(a)))
 		goto out;
-	error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
+	error = sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
 out:
 	return error;
 }
diff --git a/arch/s390/kernel/sys_s390.c b/arch/s390/kernel/sys_s390.c
index e9d94f61d50..86a74c9c9e6 100644
--- a/arch/s390/kernel/sys_s390.c
+++ b/arch/s390/kernel/sys_s390.c
@@ -32,32 +32,6 @@
 #include <asm/uaccess.h>
 #include "entry.h"
 
-/* common code for old and new mmaps */
-static inline long do_mmap2(
-	unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags,
-	unsigned long fd, unsigned long pgoff)
-{
-	long error = -EBADF;
-	struct file * file = NULL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-out:
-	return error;
-}
-
 /*
  * Perform the select(nd, in, out, ex, tv) and mmap() system
  * calls. Linux for S/390 isn't able to handle more than 5
@@ -81,7 +55,7 @@ SYSCALL_DEFINE1(mmap2, struct mmap_arg_struct __user *, arg)
 
 	if (copy_from_user(&a, arg, sizeof(a)))
 		goto out;
-	error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
+	error = sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset);
 out:
 	return error;
 }
@@ -98,7 +72,7 @@ SYSCALL_DEFINE1(s390_old_mmap, struct mmap_arg_struct __user *, arg)
 	if (a.offset & ~PAGE_MASK)
 		goto out;
 
-	error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
+	error = sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
 out:
 	return error;
 }
diff --git a/arch/score/kernel/sys_score.c b/arch/score/kernel/sys_score.c
index 00124946986..856ed68a58e 100644
--- a/arch/score/kernel/sys_score.c
+++ b/arch/score/kernel/sys_score.c
@@ -36,34 +36,16 @@ asmlinkage long
 sys_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
 	  unsigned long flags, unsigned long fd, unsigned long pgoff)
 {
-	int error = -EBADF;
-	struct file *file = NULL;
-
-	if (pgoff & (~PAGE_MASK >> 12))
-		return -EINVAL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			return error;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-
-	return error;
+	return sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);
 }
 
 asmlinkage long
 sys_mmap(unsigned long addr, unsigned long len, unsigned long prot,
-	unsigned long flags, unsigned long fd, off_t pgoff)
+	unsigned long flags, unsigned long fd, off_t offset)
 {
-	return sys_mmap2(addr, len, prot, flags, fd, pgoff >> PAGE_SHIFT);
+	if (unlikely(offset & ~PAGE_MASK))
+		return -EINVAL;
+	return sys_mmap_pgoff(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
 }
 
 asmlinkage long
diff --git a/arch/sh/kernel/sys_sh.c b/arch/sh/kernel/sys_sh.c
index 8aa5d1ceaf1..71399cde03b 100644
--- a/arch/sh/kernel/sys_sh.c
+++ b/arch/sh/kernel/sys_sh.c
@@ -28,37 +28,13 @@
 #include <asm/cacheflush.h>
 #include <asm/cachectl.h>
 
-static inline long
-do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
-	 unsigned long flags, int fd, unsigned long pgoff)
-{
-	int error = -EBADF;
-	struct file *file = NULL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-out:
-	return error;
-}
-
 asmlinkage int old_mmap(unsigned long addr, unsigned long len,
 	unsigned long prot, unsigned long flags,
 	int fd, unsigned long off)
 {
 	if (off & ~PAGE_MASK)
 		return -EINVAL;
-	return do_mmap2(addr, len, prot, flags, fd, off>>PAGE_SHIFT);
+	return sys_mmap_pgoff(addr, len, prot, flags, fd, off>>PAGE_SHIFT);
 }
 
 asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
@@ -74,7 +50,7 @@ asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
 
 	pgoff >>= PAGE_SHIFT - 12;
 
-	return do_mmap2(addr, len, prot, flags, fd, pgoff);
+	return sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff);
 }
 
 /*
diff --git a/arch/sh/mm/mmap.c b/arch/sh/mm/mmap.c
index d2984fa42d3..afeb710ec5c 100644
--- a/arch/sh/mm/mmap.c
+++ b/arch/sh/mm/mmap.c
@@ -54,7 +54,8 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
 		/* We do not accept a shared mapping if it would violate
 		 * cache aliasing constraints.
 		 */
-		if ((flags & MAP_SHARED) && (addr & shm_align_mask))
+		if ((flags & MAP_SHARED) &&
+		    ((addr - (pgoff << PAGE_SHIFT)) & shm_align_mask))
 			return -EINVAL;
 		return addr;
 	}
diff --git a/arch/sparc/kernel/sys_sparc_32.c b/arch/sparc/kernel/sys_sparc_32.c
index 03035c852a4..3a82e65d8db 100644
--- a/arch/sparc/kernel/sys_sparc_32.c
+++ b/arch/sparc/kernel/sys_sparc_32.c
@@ -45,7 +45,8 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
 		/* We do not accept a shared mapping if it would violate
 		 * cache aliasing constraints.
 		 */
-		if ((flags & MAP_SHARED) && (addr & (SHMLBA - 1)))
+		if ((flags & MAP_SHARED) &&
+		    ((addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1)))
 			return -EINVAL;
 		return addr;
 	}
@@ -79,15 +80,6 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, unsi
 	}
 }
 
-asmlinkage unsigned long sparc_brk(unsigned long brk)
-{
-	if(ARCH_SUN4C) {
-		if ((brk & 0xe0000000) != (current->mm->brk & 0xe0000000))
-			return current->mm->brk;
-	}
-	return sys_brk(brk);
-}
-
 /*
  * sys_pipe() is the normal C calling standard for creating
  * a pipe. It's not the way unix traditionally does this, though.
@@ -234,31 +226,6 @@ int sparc_mmap_check(unsigned long addr, unsigned long len)
 }
 
 /* Linux version of mmap */
-static unsigned long do_mmap2(unsigned long addr, unsigned long len,
-	unsigned long prot, unsigned long flags, unsigned long fd,
-	unsigned long pgoff)
-{
-	struct file * file = NULL;
-	unsigned long retval = -EBADF;
-
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	len = PAGE_ALIGN(len);
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-
-	down_write(&current->mm->mmap_sem);
-	retval = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-out:
-	return retval;
-}
 
 asmlinkage unsigned long sys_mmap2(unsigned long addr, unsigned long len,
 	unsigned long prot, unsigned long flags, unsigned long fd,
@@ -266,14 +233,16 @@ asmlinkage unsigned long sys_mmap2(unsigned long addr, unsigned long len,
 {
 	/* Make sure the shift for mmap2 is constant (12), no matter what PAGE_SIZE
 	   we have. */
-	return do_mmap2(addr, len, prot, flags, fd, pgoff >> (PAGE_SHIFT - 12));
+	return sys_mmap_pgoff(addr, len, prot, flags, fd,
+			      pgoff >> (PAGE_SHIFT - 12));
 }
 
 asmlinkage unsigned long sys_mmap(unsigned long addr, unsigned long len,
 	unsigned long prot, unsigned long flags, unsigned long fd,
 	unsigned long off)
 {
-	return do_mmap2(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
+	/* no alignment check? */
+	return sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
 }
 
 long sparc_remap_file_pages(unsigned long start, unsigned long size,
@@ -287,27 +256,6 @@ long sparc_remap_file_pages(unsigned long start, unsigned long size,
 				    (pgoff >> (PAGE_SHIFT - 12)), flags);
 }
 
-extern unsigned long do_mremap(unsigned long addr,
-	unsigned long old_len, unsigned long new_len,
-	unsigned long flags, unsigned long new_addr);
-                
-asmlinkage unsigned long sparc_mremap(unsigned long addr,
-	unsigned long old_len, unsigned long new_len,
-	unsigned long flags, unsigned long new_addr)
-{
-	unsigned long ret = -EINVAL;
-
-	if (unlikely(sparc_mmap_check(addr, old_len)))
-		goto out;
-	if (unlikely(sparc_mmap_check(new_addr, new_len)))
-		goto out;
-	down_write(&current->mm->mmap_sem);
-	ret = do_mremap(addr, old_len, new_len, flags, new_addr);
-	up_write(&current->mm->mmap_sem);
-out:
-	return ret;       
-}
-
 /* we come to here via sys_nis_syscall so it can setup the regs argument */
 asmlinkage unsigned long
 c_sys_nis_syscall (struct pt_regs *regs)
diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c
index e2d102447a4..cfa0e19abe3 100644
--- a/arch/sparc/kernel/sys_sparc_64.c
+++ b/arch/sparc/kernel/sys_sparc_64.c
@@ -317,10 +317,14 @@ bottomup:
 unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, unsigned long len, unsigned long pgoff, unsigned long flags)
 {
 	unsigned long align_goal, addr = -ENOMEM;
+	unsigned long (*get_area)(struct file *, unsigned long,
+				  unsigned long, unsigned long, unsigned long);
+
+	get_area = current->mm->get_unmapped_area;
 
 	if (flags & MAP_FIXED) {
 		/* Ok, don't mess with it. */
-		return get_unmapped_area(NULL, orig_addr, len, pgoff, flags);
+		return get_area(NULL, orig_addr, len, pgoff, flags);
 	}
 	flags &= ~MAP_SHARED;
 
@@ -333,7 +337,7 @@ unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, u
 		align_goal = (64UL * 1024);
 
 	do {
-		addr = get_unmapped_area(NULL, orig_addr, len + (align_goal - PAGE_SIZE), pgoff, flags);
+		addr = get_area(NULL, orig_addr, len + (align_goal - PAGE_SIZE), pgoff, flags);
 		if (!(addr & ~PAGE_MASK)) {
 			addr = (addr + (align_goal - 1UL)) & ~(align_goal - 1UL);
 			break;
@@ -351,7 +355,7 @@ unsigned long get_fb_unmapped_area(struct file *filp, unsigned long orig_addr, u
 	 * be obtained.
 	 */
 	if (addr & ~PAGE_MASK)
-		addr = get_unmapped_area(NULL, orig_addr, len, pgoff, flags);
+		addr = get_area(NULL, orig_addr, len, pgoff, flags);
 
 	return addr;
 }
@@ -399,18 +403,6 @@ void arch_pick_mmap_layout(struct mm_struct *mm)
 	}
 }
 
-SYSCALL_DEFINE1(sparc_brk, unsigned long, brk)
-{
-	/* People could try to be nasty and use ta 0x6d in 32bit programs */
-	if (test_thread_flag(TIF_32BIT) && brk >= STACK_TOP32)
-		return current->mm->brk;
-
-	if (unlikely(straddles_64bit_va_hole(current->mm->brk, brk)))
-		return current->mm->brk;
-
-	return sys_brk(brk);
-}
-                                                                
 /*
  * sys_pipe() is the normal C calling standard for creating
  * a pipe. It's not the way unix traditionally does this, though.
@@ -568,23 +560,13 @@ SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
 		unsigned long, prot, unsigned long, flags, unsigned long, fd,
 		unsigned long, off)
 {
-	struct file * file = NULL;
-	unsigned long retval = -EBADF;
-
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	len = PAGE_ALIGN(len);
+	unsigned long retval = -EINVAL;
 
-	down_write(&current->mm->mmap_sem);
-	retval = do_mmap(file, addr, len, prot, flags, off);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
+	if ((off + PAGE_ALIGN(len)) < off)
+		goto out;
+	if (off & ~PAGE_MASK)
+		goto out;
+	retval = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
 out:
 	return retval;
 }
@@ -614,12 +596,6 @@ SYSCALL_DEFINE5(64_mremap, unsigned long, addr,	unsigned long, old_len,
 
 	if (test_thread_flag(TIF_32BIT))
 		goto out;
-	if (unlikely(new_len >= VA_EXCLUDE_START))
-		goto out;
-	if (unlikely(sparc_mmap_check(addr, old_len)))
-		goto out;
-	if (unlikely(sparc_mmap_check(new_addr, new_len)))
-		goto out;
 
 	down_write(&current->mm->mmap_sem);
 	ret = do_mremap(addr, old_len, new_len, flags, new_addr);
diff --git a/arch/sparc/kernel/systbls.h b/arch/sparc/kernel/systbls.h
index a63c5d2d984..d2f999ae2b8 100644
--- a/arch/sparc/kernel/systbls.h
+++ b/arch/sparc/kernel/systbls.h
@@ -9,7 +9,6 @@
 struct new_utsname;
 
 extern asmlinkage unsigned long sys_getpagesize(void);
-extern asmlinkage unsigned long sparc_brk(unsigned long brk);
 extern asmlinkage long sparc_pipe(struct pt_regs *regs);
 extern asmlinkage long sys_ipc(unsigned int call, int first,
 			       unsigned long second,
diff --git a/arch/sparc/kernel/systbls_32.S b/arch/sparc/kernel/systbls_32.S
index 0f1658d3749..14f950afcd6 100644
--- a/arch/sparc/kernel/systbls_32.S
+++ b/arch/sparc/kernel/systbls_32.S
@@ -19,7 +19,7 @@ sys_call_table:
 /*0*/	.long sys_restart_syscall, sys_exit, sys_fork, sys_read, sys_write
 /*5*/	.long sys_open, sys_close, sys_wait4, sys_creat, sys_link
 /*10*/  .long sys_unlink, sunos_execv, sys_chdir, sys_chown16, sys_mknod
-/*15*/	.long sys_chmod, sys_lchown16, sparc_brk, sys_nis_syscall, sys_lseek
+/*15*/	.long sys_chmod, sys_lchown16, sys_brk, sys_nis_syscall, sys_lseek
 /*20*/	.long sys_getpid, sys_capget, sys_capset, sys_setuid16, sys_getuid16
 /*25*/	.long sys_vmsplice, sys_ptrace, sys_alarm, sys_sigaltstack, sys_pause
 /*30*/	.long sys_utime, sys_lchown, sys_fchown, sys_access, sys_nice
@@ -67,7 +67,7 @@ sys_call_table:
 /*235*/	.long sys_fstatfs64, sys_llseek, sys_mlock, sys_munlock, sys_mlockall
 /*240*/	.long sys_munlockall, sys_sched_setparam, sys_sched_getparam, sys_sched_setscheduler, sys_sched_getscheduler
 /*245*/	.long sys_sched_yield, sys_sched_get_priority_max, sys_sched_get_priority_min, sys_sched_rr_get_interval, sys_nanosleep
-/*250*/	.long sparc_mremap, sys_sysctl, sys_getsid, sys_fdatasync, sys_nfsservctl
+/*250*/	.long sys_mremap, sys_sysctl, sys_getsid, sys_fdatasync, sys_nfsservctl
 /*255*/	.long sys_sync_file_range, sys_clock_settime, sys_clock_gettime, sys_clock_getres, sys_clock_nanosleep
 /*260*/	.long sys_sched_getaffinity, sys_sched_setaffinity, sys_timer_settime, sys_timer_gettime, sys_timer_getoverrun
 /*265*/	.long sys_timer_delete, sys_timer_create, sys_nis_syscall, sys_io_setup, sys_io_destroy
diff --git a/arch/sparc/kernel/systbls_64.S b/arch/sparc/kernel/systbls_64.S
index 009825f6e73..f63c871eebb 100644
--- a/arch/sparc/kernel/systbls_64.S
+++ b/arch/sparc/kernel/systbls_64.S
@@ -21,7 +21,7 @@ sys_call_table32:
 /*0*/	.word sys_restart_syscall, sys32_exit, sys_fork, sys_read, sys_write
 /*5*/	.word sys32_open, sys_close, sys32_wait4, sys32_creat, sys_link
 /*10*/  .word sys_unlink, sunos_execv, sys_chdir, sys_chown16, sys32_mknod
-/*15*/	.word sys_chmod, sys_lchown16, sys_sparc_brk, sys32_perfctr, sys32_lseek
+/*15*/	.word sys_chmod, sys_lchown16, sys_brk, sys32_perfctr, sys32_lseek
 /*20*/	.word sys_getpid, sys_capget, sys_capset, sys_setuid16, sys_getuid16
 /*25*/	.word sys32_vmsplice, compat_sys_ptrace, sys_alarm, sys32_sigaltstack, sys_pause
 /*30*/	.word compat_sys_utime, sys_lchown, sys_fchown, sys32_access, sys32_nice
@@ -96,7 +96,7 @@ sys_call_table:
 /*0*/	.word sys_restart_syscall, sparc_exit, sys_fork, sys_read, sys_write
 /*5*/	.word sys_open, sys_close, sys_wait4, sys_creat, sys_link
 /*10*/  .word sys_unlink, sys_nis_syscall, sys_chdir, sys_chown, sys_mknod
-/*15*/	.word sys_chmod, sys_lchown, sys_sparc_brk, sys_perfctr, sys_lseek
+/*15*/	.word sys_chmod, sys_lchown, sys_brk, sys_perfctr, sys_lseek
 /*20*/	.word sys_getpid, sys_capget, sys_capset, sys_setuid, sys_getuid
 /*25*/	.word sys_vmsplice, sys_ptrace, sys_alarm, sys_sigaltstack, sys_nis_syscall
 /*30*/	.word sys_utime, sys_nis_syscall, sys_nis_syscall, sys_access, sys_nice
diff --git a/arch/um/kernel/syscall.c b/arch/um/kernel/syscall.c
index a4625c7b2bf..cccab850c27 100644
--- a/arch/um/kernel/syscall.c
+++ b/arch/um/kernel/syscall.c
@@ -8,6 +8,7 @@
 #include "linux/mm.h"
 #include "linux/sched.h"
 #include "linux/utsname.h"
+#include "linux/syscalls.h"
 #include "asm/current.h"
 #include "asm/mman.h"
 #include "asm/uaccess.h"
@@ -37,31 +38,6 @@ long sys_vfork(void)
 	return ret;
 }
 
-/* common code for old and new mmaps */
-long sys_mmap2(unsigned long addr, unsigned long len,
-	       unsigned long prot, unsigned long flags,
-	       unsigned long fd, unsigned long pgoff)
-{
-	long error = -EBADF;
-	struct file * file = NULL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
- out:
-	return error;
-}
-
 long old_mmap(unsigned long addr, unsigned long len,
 	      unsigned long prot, unsigned long flags,
 	      unsigned long fd, unsigned long offset)
@@ -70,7 +46,7 @@ long old_mmap(unsigned long addr, unsigned long len,
 	if (offset & ~PAGE_MASK)
 		goto out;
 
-	err = sys_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
+	err = sys_mmap_pgoff(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
  out:
 	return err;
 }
diff --git a/arch/um/sys-i386/shared/sysdep/syscalls.h b/arch/um/sys-i386/shared/sysdep/syscalls.h
index 905698197e3..e7787679e31 100644
--- a/arch/um/sys-i386/shared/sysdep/syscalls.h
+++ b/arch/um/sys-i386/shared/sysdep/syscalls.h
@@ -20,7 +20,3 @@ extern syscall_handler_t *sys_call_table[];
 #define EXECUTE_SYSCALL(syscall, regs) \
 	((long (*)(struct syscall_args)) \
 	 (*sys_call_table[syscall]))(SYSCALL_ARGS(&regs->regs))
-
-extern long sys_mmap2(unsigned long addr, unsigned long len,
-		      unsigned long prot, unsigned long flags,
-		      unsigned long fd, unsigned long pgoff);
diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S
index 581b0568fe1..5294d844673 100644
--- a/arch/x86/ia32/ia32entry.S
+++ b/arch/x86/ia32/ia32entry.S
@@ -696,7 +696,7 @@ ia32_sys_call_table:
 	.quad quiet_ni_syscall		/* streams2 */
 	.quad stub32_vfork            /* 190 */
 	.quad compat_sys_getrlimit
-	.quad sys32_mmap2
+	.quad sys_mmap_pgoff
 	.quad sys32_truncate64
 	.quad sys32_ftruncate64
 	.quad sys32_stat64		/* 195 */
diff --git a/arch/x86/ia32/sys_ia32.c b/arch/x86/ia32/sys_ia32.c
index 9f552719882..016218c353e 100644
--- a/arch/x86/ia32/sys_ia32.c
+++ b/arch/x86/ia32/sys_ia32.c
@@ -155,9 +155,6 @@ struct mmap_arg_struct {
 asmlinkage long sys32_mmap(struct mmap_arg_struct __user *arg)
 {
 	struct mmap_arg_struct a;
-	struct file *file = NULL;
-	unsigned long retval;
-	struct mm_struct *mm ;
 
 	if (copy_from_user(&a, arg, sizeof(a)))
 		return -EFAULT;
@@ -165,22 +162,8 @@ asmlinkage long sys32_mmap(struct mmap_arg_struct __user *arg)
 	if (a.offset & ~PAGE_MASK)
 		return -EINVAL;
 
-	if (!(a.flags & MAP_ANONYMOUS)) {
-		file = fget(a.fd);
-		if (!file)
-			return -EBADF;
-	}
-
-	mm = current->mm;
-	down_write(&mm->mmap_sem);
-	retval = do_mmap_pgoff(file, a.addr, a.len, a.prot, a.flags,
+	return sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd,
 			       a.offset>>PAGE_SHIFT);
-	if (file)
-		fput(file);
-
-	up_write(&mm->mmap_sem);
-
-	return retval;
 }
 
 asmlinkage long sys32_mprotect(unsigned long start, size_t len,
@@ -539,30 +522,6 @@ asmlinkage long sys32_sendfile(int out_fd, int in_fd,
 	return ret;
 }
 
-asmlinkage long sys32_mmap2(unsigned long addr, unsigned long len,
-			    unsigned long prot, unsigned long flags,
-			    unsigned long fd, unsigned long pgoff)
-{
-	struct mm_struct *mm = current->mm;
-	unsigned long error;
-	struct file *file = NULL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			return -EBADF;
-	}
-
-	down_write(&mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&mm->mmap_sem);
-
-	if (file)
-		fput(file);
-	return error;
-}
-
 asmlinkage long sys32_olduname(struct oldold_utsname __user *name)
 {
 	char *arch = "x86_64";
diff --git a/arch/x86/include/asm/sys_ia32.h b/arch/x86/include/asm/sys_ia32.h
index 72a6dcd1299..77c1184bee4 100644
--- a/arch/x86/include/asm/sys_ia32.h
+++ b/arch/x86/include/asm/sys_ia32.h
@@ -62,9 +62,6 @@ asmlinkage long sys32_pwrite(unsigned int, char __user *, u32, u32, u32);
 asmlinkage long sys32_personality(unsigned long);
 asmlinkage long sys32_sendfile(int, int, compat_off_t __user *, s32);
 
-asmlinkage long sys32_mmap2(unsigned long, unsigned long, unsigned long,
-			    unsigned long, unsigned long, unsigned long);
-
 struct oldold_utsname;
 struct old_utsname;
 asmlinkage long sys32_olduname(struct oldold_utsname __user *);
diff --git a/arch/x86/include/asm/syscalls.h b/arch/x86/include/asm/syscalls.h
index 372b76edd63..1bb6e395881 100644
--- a/arch/x86/include/asm/syscalls.h
+++ b/arch/x86/include/asm/syscalls.h
@@ -55,8 +55,6 @@ struct sel_arg_struct;
 struct oldold_utsname;
 struct old_utsname;
 
-asmlinkage long sys_mmap2(unsigned long, unsigned long, unsigned long,
-			  unsigned long, unsigned long, unsigned long);
 asmlinkage int old_mmap(struct mmap_arg_struct __user *);
 asmlinkage int old_select(struct sel_arg_struct __user *);
 asmlinkage int sys_ipc(uint, int, int, int, void __user *, long);
diff --git a/arch/x86/kernel/sys_i386_32.c b/arch/x86/kernel/sys_i386_32.c
index 1884a8d12bf..dee1ff7cba5 100644
--- a/arch/x86/kernel/sys_i386_32.c
+++ b/arch/x86/kernel/sys_i386_32.c
@@ -24,31 +24,6 @@
 
 #include <asm/syscalls.h>
 
-asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
-			  unsigned long prot, unsigned long flags,
-			  unsigned long fd, unsigned long pgoff)
-{
-	int error = -EBADF;
-	struct file *file = NULL;
-	struct mm_struct *mm = current->mm;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	down_write(&mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&mm->mmap_sem);
-
-	if (file)
-		fput(file);
-out:
-	return error;
-}
-
 /*
  * Perform the select(nd, in, out, ex, tv) and mmap() system
  * calls. Linux/i386 didn't use to be able to handle more than
@@ -77,7 +52,7 @@ asmlinkage int old_mmap(struct mmap_arg_struct __user *arg)
 	if (a.offset & ~PAGE_MASK)
 		goto out;
 
-	err = sys_mmap2(a.addr, a.len, a.prot, a.flags,
+	err = sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags,
 			a.fd, a.offset >> PAGE_SHIFT);
 out:
 	return err;
diff --git a/arch/x86/kernel/sys_x86_64.c b/arch/x86/kernel/sys_x86_64.c
index 45e00eb09c3..8aa2057efd1 100644
--- a/arch/x86/kernel/sys_x86_64.c
+++ b/arch/x86/kernel/sys_x86_64.c
@@ -23,26 +23,11 @@ SYSCALL_DEFINE6(mmap, unsigned long, addr, unsigned long, len,
 		unsigned long, fd, unsigned long, off)
 {
 	long error;
-	struct file *file;
-
 	error = -EINVAL;
 	if (off & ~PAGE_MASK)
 		goto out;
 
-	error = -EBADF;
-	file = NULL;
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, off >> PAGE_SHIFT);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
+	error = sys_mmap_pgoff(addr, len, prot, flags, fd, off >> PAGE_SHIFT);
 out:
 	return error;
 }
diff --git a/arch/x86/kernel/syscall_table_32.S b/arch/x86/kernel/syscall_table_32.S
index 0157cd26d7c..76d70a45128 100644
--- a/arch/x86/kernel/syscall_table_32.S
+++ b/arch/x86/kernel/syscall_table_32.S
@@ -191,7 +191,7 @@ ENTRY(sys_call_table)
 	.long sys_ni_syscall	/* reserved for streams2 */
 	.long ptregs_vfork	/* 190 */
 	.long sys_getrlimit
-	.long sys_mmap2
+	.long sys_mmap_pgoff
 	.long sys_truncate64
 	.long sys_ftruncate64
 	.long sys_stat64	/* 195 */
diff --git a/arch/xtensa/include/asm/syscall.h b/arch/xtensa/include/asm/syscall.h
index 05cebf8f62b..4352dbe1186 100644
--- a/arch/xtensa/include/asm/syscall.h
+++ b/arch/xtensa/include/asm/syscall.h
@@ -13,8 +13,6 @@ struct sigaction;
 asmlinkage long xtensa_execve(char*, char**, char**, struct pt_regs*);
 asmlinkage long xtensa_clone(unsigned long, unsigned long, struct pt_regs*);
 asmlinkage long xtensa_pipe(int __user *);
-asmlinkage long xtensa_mmap2(unsigned long, unsigned long, unsigned long,
-    			     unsigned long, unsigned long, unsigned long);
 asmlinkage long xtensa_ptrace(long, long, long, long);
 asmlinkage long xtensa_sigreturn(struct pt_regs*);
 asmlinkage long xtensa_rt_sigreturn(struct pt_regs*);
diff --git a/arch/xtensa/include/asm/unistd.h b/arch/xtensa/include/asm/unistd.h
index c092c8fbb2c..9a5c354d213 100644
--- a/arch/xtensa/include/asm/unistd.h
+++ b/arch/xtensa/include/asm/unistd.h
@@ -189,7 +189,7 @@ __SYSCALL( 79, sys_fremovexattr, 2)
 /* File Map / Shared Memory Operations */
 
 #define __NR_mmap2 				 80
-__SYSCALL( 80, xtensa_mmap2, 6)
+__SYSCALL( 80, sys_mmap_pgoff, 6)
 #define __NR_munmap 				 81
 __SYSCALL( 81, sys_munmap, 2)
 #define __NR_mprotect 				 82
diff --git a/arch/xtensa/kernel/syscall.c b/arch/xtensa/kernel/syscall.c
index ac15ecbdf91..1e67bab775c 100644
--- a/arch/xtensa/kernel/syscall.c
+++ b/arch/xtensa/kernel/syscall.c
@@ -57,31 +57,6 @@ asmlinkage long xtensa_pipe(int __user *userfds)
 	return error;
 }
 
-
-asmlinkage long xtensa_mmap2(unsigned long addr, unsigned long len,
-   			     unsigned long prot, unsigned long flags,
-			     unsigned long fd, unsigned long pgoff)
-{
-	int error = -EBADF;
-	struct file * file = NULL;
-
-	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
-	if (!(flags & MAP_ANONYMOUS)) {
-		file = fget(fd);
-		if (!file)
-			goto out;
-	}
-
-	down_write(&current->mm->mmap_sem);
-	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
-	up_write(&current->mm->mmap_sem);
-
-	if (file)
-		fput(file);
-out:
-	return error;
-}
-
 asmlinkage long xtensa_shmat(int shmid, char __user *shmaddr, int shmflg)
 {
 	unsigned long ret;
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index a990ace1a83..93515c6190a 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -879,4 +879,8 @@ int kernel_execve(const char *filename, char *const argv[], char *const envp[]);
 asmlinkage long sys_perf_event_open(
 		struct perf_event_attr __user *attr_uptr,
 		pid_t pid, int cpu, int group_fd, unsigned long flags);
+
+asmlinkage long sys_mmap_pgoff(unsigned long addr, unsigned long len,
+			unsigned long prot, unsigned long flags,
+			unsigned long fd, unsigned long pgoff);
 #endif
diff --git a/ipc/shm.c b/ipc/shm.c
index 464694e0aa4..11bec626c22 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -290,28 +290,28 @@ static unsigned long shm_get_unmapped_area(struct file *file,
 	unsigned long flags)
 {
 	struct shm_file_data *sfd = shm_file_data(file);
-	return get_unmapped_area(sfd->file, addr, len, pgoff, flags);
-}
-
-int is_file_shm_hugepages(struct file *file)
-{
-	int ret = 0;
-
-	if (file->f_op == &shm_file_operations) {
-		struct shm_file_data *sfd;
-		sfd = shm_file_data(file);
-		ret = is_file_hugepages(sfd->file);
-	}
-	return ret;
+	return sfd->file->f_op->get_unmapped_area(sfd->file, addr, len,
+						pgoff, flags);
 }
 
 static const struct file_operations shm_file_operations = {
 	.mmap		= shm_mmap,
 	.fsync		= shm_fsync,
 	.release	= shm_release,
+};
+
+static const struct file_operations shm_file_operations_huge = {
+	.mmap		= shm_mmap,
+	.fsync		= shm_fsync,
+	.release	= shm_release,
 	.get_unmapped_area	= shm_get_unmapped_area,
 };
 
+int is_file_shm_hugepages(struct file *file)
+{
+	return file->f_op == &shm_file_operations_huge;
+}
+
 static const struct vm_operations_struct shm_vm_ops = {
 	.open	= shm_open,	/* callback for a new vm-area open */
 	.close	= shm_close,	/* callback for when the vm-area is released */
@@ -889,7 +889,10 @@ long do_shmat(int shmid, char __user *shmaddr, int shmflg, ulong *raddr)
 	if (!sfd)
 		goto out_put_dentry;
 
-	file = alloc_file(path.mnt, path.dentry, f_mode, &shm_file_operations);
+	file = alloc_file(path.mnt, path.dentry, f_mode,
+			is_file_hugepages(shp->shm_file) ?
+				&shm_file_operations_huge :
+				&shm_file_operations);
 	if (!file)
 		goto out_free;
 	ima_counts_get(file);
diff --git a/mm/mmap.c b/mm/mmap.c
index 73f5e4b6401..ae197468b35 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -932,13 +932,9 @@ unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
 	if (!(flags & MAP_FIXED))
 		addr = round_hint_to_min(addr);
 
-	error = arch_mmap_check(addr, len, flags);
-	if (error)
-		return error;
-
 	/* Careful about overflows.. */
 	len = PAGE_ALIGN(len);
-	if (!len || len > TASK_SIZE)
+	if (!len)
 		return -ENOMEM;
 
 	/* offset overflow? */
@@ -949,24 +945,6 @@ unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
 	if (mm->map_count > sysctl_max_map_count)
 		return -ENOMEM;
 
-	if (flags & MAP_HUGETLB) {
-		struct user_struct *user = NULL;
-		if (file)
-			return -EINVAL;
-
-		/*
-		 * VM_NORESERVE is used because the reservations will be
-		 * taken when vm_ops->mmap() is called
-		 * A dummy user value is used because we are not locking
-		 * memory so no accounting is necessary
-		 */
-		len = ALIGN(len, huge_page_size(&default_hstate));
-		file = hugetlb_file_setup(HUGETLB_ANON_FILE, len, VM_NORESERVE,
-						&user, HUGETLB_ANONHUGE_INODE);
-		if (IS_ERR(file))
-			return PTR_ERR(file);
-	}
-
 	/* Obtain the address to map to. we verify (or select) it and ensure
 	 * that it represents a valid section of the address space.
 	 */
@@ -1459,6 +1437,14 @@ get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
 	unsigned long (*get_area)(struct file *, unsigned long,
 				  unsigned long, unsigned long, unsigned long);
 
+	unsigned long error = arch_mmap_check(addr, len, flags);
+	if (error)
+		return error;
+
+	/* Careful about overflows.. */
+	if (len > TASK_SIZE)
+		return -ENOMEM;
+
 	get_area = current->mm->get_unmapped_area;
 	if (file && file->f_op && file->f_op->get_unmapped_area)
 		get_area = file->f_op->get_unmapped_area;
@@ -2003,20 +1989,14 @@ unsigned long do_brk(unsigned long addr, unsigned long len)
 	if (!len)
 		return addr;
 
-	if ((addr + len) > TASK_SIZE || (addr + len) < addr)
-		return -EINVAL;
-
-	if (is_hugepage_only_range(mm, addr, len))
-		return -EINVAL;
-
 	error = security_file_mmap(NULL, 0, 0, 0, addr, 1);
 	if (error)
 		return error;
 
 	flags = VM_DATA_DEFAULT_FLAGS | VM_ACCOUNT | mm->def_flags;
 
-	error = arch_mmap_check(addr, len, flags);
-	if (error)
+	error = get_unmapped_area(NULL, addr, len, 0, MAP_FIXED);
+	if (error & ~PAGE_MASK)
 		return error;
 
 	/*
diff --git a/mm/mremap.c b/mm/mremap.c
index 97bff254771..845190898d5 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -261,6 +261,137 @@ static unsigned long move_vma(struct vm_area_struct *vma,
 	return new_addr;
 }
 
+static struct vm_area_struct *vma_to_resize(unsigned long addr,
+	unsigned long old_len, unsigned long new_len, unsigned long *p)
+{
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma = find_vma(mm, addr);
+
+	if (!vma || vma->vm_start > addr)
+		goto Efault;
+
+	if (is_vm_hugetlb_page(vma))
+		goto Einval;
+
+	/* We can't remap across vm area boundaries */
+	if (old_len > vma->vm_end - addr)
+		goto Efault;
+
+	if (vma->vm_flags & (VM_DONTEXPAND | VM_PFNMAP)) {
+		if (new_len > old_len)
+			goto Efault;
+	}
+
+	if (vma->vm_flags & VM_LOCKED) {
+		unsigned long locked, lock_limit;
+		locked = mm->locked_vm << PAGE_SHIFT;
+		lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
+		locked += new_len - old_len;
+		if (locked > lock_limit && !capable(CAP_IPC_LOCK))
+			goto Eagain;
+	}
+
+	if (!may_expand_vm(mm, (new_len - old_len) >> PAGE_SHIFT))
+		goto Enomem;
+
+	if (vma->vm_flags & VM_ACCOUNT) {
+		unsigned long charged = (new_len - old_len) >> PAGE_SHIFT;
+		if (security_vm_enough_memory(charged))
+			goto Efault;
+		*p = charged;
+	}
+
+	return vma;
+
+Efault:	/* very odd choice for most of the cases, but... */
+	return ERR_PTR(-EFAULT);
+Einval:
+	return ERR_PTR(-EINVAL);
+Enomem:
+	return ERR_PTR(-ENOMEM);
+Eagain:
+	return ERR_PTR(-EAGAIN);
+}
+
+static unsigned long mremap_to(unsigned long addr,
+	unsigned long old_len, unsigned long new_addr,
+	unsigned long new_len)
+{
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
+	unsigned long ret = -EINVAL;
+	unsigned long charged = 0;
+	unsigned long map_flags;
+
+	if (new_addr & ~PAGE_MASK)
+		goto out;
+
+	if (new_len > TASK_SIZE || new_addr > TASK_SIZE - new_len)
+		goto out;
+
+	/* Check if the location we're moving into overlaps the
+	 * old location at all, and fail if it does.
+	 */
+	if ((new_addr <= addr) && (new_addr+new_len) > addr)
+		goto out;
+
+	if ((addr <= new_addr) && (addr+old_len) > new_addr)
+		goto out;
+
+	ret = security_file_mmap(NULL, 0, 0, 0, new_addr, 1);
+	if (ret)
+		goto out;
+
+	ret = do_munmap(mm, new_addr, new_len);
+	if (ret)
+		goto out;
+
+	if (old_len >= new_len) {
+		ret = do_munmap(mm, addr+new_len, old_len - new_len);
+		if (ret && old_len != new_len)
+			goto out;
+		old_len = new_len;
+	}
+
+	vma = vma_to_resize(addr, old_len, new_len, &charged);
+	if (IS_ERR(vma)) {
+		ret = PTR_ERR(vma);
+		goto out;
+	}
+
+	map_flags = MAP_FIXED;
+	if (vma->vm_flags & VM_MAYSHARE)
+		map_flags |= MAP_SHARED;
+
+	ret = get_unmapped_area(vma->vm_file, new_addr, new_len, vma->vm_pgoff +
+				((addr - vma->vm_start) >> PAGE_SHIFT),
+				map_flags);
+	if (ret & ~PAGE_MASK)
+		goto out1;
+
+	ret = move_vma(vma, addr, old_len, new_len, new_addr);
+	if (!(ret & ~PAGE_MASK))
+		goto out;
+out1:
+	vm_unacct_memory(charged);
+
+out:
+	return ret;
+}
+
+static int vma_expandable(struct vm_area_struct *vma, unsigned long delta)
+{
+	unsigned long end = vma->vm_end + delta;
+	if (end < vma->vm_end) /* overflow */
+		return 0;
+	if (vma->vm_next && vma->vm_next->vm_start < end) /* intersection */
+		return 0;
+	if (get_unmapped_area(NULL, vma->vm_start, end - vma->vm_start,
+			      0, MAP_FIXED) & ~PAGE_MASK)
+		return 0;
+	return 1;
+}
+
 /*
  * Expand (or shrink) an existing mapping, potentially moving it at the
  * same time (controlled by the MREMAP_MAYMOVE flag and available VM space)
@@ -294,32 +425,10 @@ unsigned long do_mremap(unsigned long addr,
 	if (!new_len)
 		goto out;
 
-	/* new_addr is only valid if MREMAP_FIXED is specified */
 	if (flags & MREMAP_FIXED) {
-		if (new_addr & ~PAGE_MASK)
-			goto out;
-		if (!(flags & MREMAP_MAYMOVE))
-			goto out;
-
-		if (new_len > TASK_SIZE || new_addr > TASK_SIZE - new_len)
-			goto out;
-
-		/* Check if the location we're moving into overlaps the
-		 * old location at all, and fail if it does.
-		 */
-		if ((new_addr <= addr) && (new_addr+new_len) > addr)
-			goto out;
-
-		if ((addr <= new_addr) && (addr+old_len) > new_addr)
-			goto out;
-
-		ret = security_file_mmap(NULL, 0, 0, 0, new_addr, 1);
-		if (ret)
-			goto out;
-
-		ret = do_munmap(mm, new_addr, new_len);
-		if (ret)
-			goto out;
+		if (flags & MREMAP_MAYMOVE)
+			ret = mremap_to(addr, old_len, new_addr, new_len);
+		goto out;
 	}
 
 	/*
@@ -332,60 +441,23 @@ unsigned long do_mremap(unsigned long addr,
 		if (ret && old_len != new_len)
 			goto out;
 		ret = addr;
-		if (!(flags & MREMAP_FIXED) || (new_addr == addr))
-			goto out;
-		old_len = new_len;
+		goto out;
 	}
 
 	/*
-	 * Ok, we need to grow..  or relocate.
+	 * Ok, we need to grow..
 	 */
-	ret = -EFAULT;
-	vma = find_vma(mm, addr);
-	if (!vma || vma->vm_start > addr)
-		goto out;
-	if (is_vm_hugetlb_page(vma)) {
-		ret = -EINVAL;
-		goto out;
-	}
-	/* We can't remap across vm area boundaries */
-	if (old_len > vma->vm_end - addr)
-		goto out;
-	if (vma->vm_flags & (VM_DONTEXPAND | VM_PFNMAP)) {
-		if (new_len > old_len)
-			goto out;
-	}
-	if (vma->vm_flags & VM_LOCKED) {
-		unsigned long locked, lock_limit;
-		locked = mm->locked_vm << PAGE_SHIFT;
-		lock_limit = current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur;
-		locked += new_len - old_len;
-		ret = -EAGAIN;
-		if (locked > lock_limit && !capable(CAP_IPC_LOCK))
-			goto out;
-	}
-	if (!may_expand_vm(mm, (new_len - old_len) >> PAGE_SHIFT)) {
-		ret = -ENOMEM;
+	vma = vma_to_resize(addr, old_len, new_len, &charged);
+	if (IS_ERR(vma)) {
+		ret = PTR_ERR(vma);
 		goto out;
 	}
 
-	if (vma->vm_flags & VM_ACCOUNT) {
-		charged = (new_len - old_len) >> PAGE_SHIFT;
-		if (security_vm_enough_memory(charged))
-			goto out_nc;
-	}
-
 	/* old_len exactly to the end of the area..
-	 * And we're not relocating the area.
 	 */
-	if (old_len == vma->vm_end - addr &&
-	    !((flags & MREMAP_FIXED) && (addr != new_addr)) &&
-	    (old_len != new_len || !(flags & MREMAP_MAYMOVE))) {
-		unsigned long max_addr = TASK_SIZE;
-		if (vma->vm_next)
-			max_addr = vma->vm_next->vm_start;
+	if (old_len == vma->vm_end - addr) {
 		/* can we just expand the current mapping? */
-		if (max_addr - addr >= new_len) {
+		if (vma_expandable(vma, new_len - old_len)) {
 			int pages = (new_len - old_len) >> PAGE_SHIFT;
 
 			vma_adjust(vma, vma->vm_start,
@@ -409,28 +481,27 @@ unsigned long do_mremap(unsigned long addr,
 	 */
 	ret = -ENOMEM;
 	if (flags & MREMAP_MAYMOVE) {
-		if (!(flags & MREMAP_FIXED)) {
-			unsigned long map_flags = 0;
-			if (vma->vm_flags & VM_MAYSHARE)
-				map_flags |= MAP_SHARED;
-
-			new_addr = get_unmapped_area(vma->vm_file, 0, new_len,
-						vma->vm_pgoff, map_flags);
-			if (new_addr & ~PAGE_MASK) {
-				ret = new_addr;
-				goto out;
-			}
-
-			ret = security_file_mmap(NULL, 0, 0, 0, new_addr, 1);
-			if (ret)
-				goto out;
+		unsigned long map_flags = 0;
+		if (vma->vm_flags & VM_MAYSHARE)
+			map_flags |= MAP_SHARED;
+
+		new_addr = get_unmapped_area(vma->vm_file, 0, new_len,
+					vma->vm_pgoff +
+					((addr - vma->vm_start) >> PAGE_SHIFT),
+					map_flags);
+		if (new_addr & ~PAGE_MASK) {
+			ret = new_addr;
+			goto out;
 		}
+
+		ret = security_file_mmap(NULL, 0, 0, 0, new_addr, 1);
+		if (ret)
+			goto out;
 		ret = move_vma(vma, addr, old_len, new_len, new_addr);
 	}
 out:
 	if (ret & ~PAGE_MASK)
 		vm_unacct_memory(charged);
-out_nc:
 	return ret;
 }
 
diff --git a/mm/util.c b/mm/util.c
index 7c35ad95f92..b377ce43080 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -4,6 +4,10 @@
 #include <linux/module.h>
 #include <linux/err.h>
 #include <linux/sched.h>
+#include <linux/hugetlb.h>
+#include <linux/syscalls.h>
+#include <linux/mman.h>
+#include <linux/file.h>
 #include <asm/uaccess.h>
 
 #define CREATE_TRACE_POINTS
@@ -268,6 +272,46 @@ int __attribute__((weak)) get_user_pages_fast(unsigned long start,
 }
 EXPORT_SYMBOL_GPL(get_user_pages_fast);
 
+SYSCALL_DEFINE6(mmap_pgoff, unsigned long, addr, unsigned long, len,
+		unsigned long, prot, unsigned long, flags,
+		unsigned long, fd, unsigned long, pgoff)
+{
+	struct file * file = NULL;
+	unsigned long retval = -EBADF;
+
+	if (!(flags & MAP_ANONYMOUS)) {
+		if (unlikely(flags & MAP_HUGETLB))
+			return -EINVAL;
+		file = fget(fd);
+		if (!file)
+			goto out;
+	} else if (flags & MAP_HUGETLB) {
+		struct user_struct *user = NULL;
+		/*
+		 * VM_NORESERVE is used because the reservations will be
+		 * taken when vm_ops->mmap() is called
+		 * A dummy user value is used because we are not locking
+		 * memory so no accounting is necessary
+		 */
+		len = ALIGN(len, huge_page_size(&default_hstate));
+		file = hugetlb_file_setup(HUGETLB_ANON_FILE, len, VM_NORESERVE,
+						&user, HUGETLB_ANONHUGE_INODE);
+		if (IS_ERR(file))
+			return PTR_ERR(file);
+	}
+
+	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
+
+	down_write(&current->mm->mmap_sem);
+	retval = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
+	up_write(&current->mm->mmap_sem);
+
+	if (file)
+		fput(file);
+out:
+	return retval;
+}
+
 /* Tracepoints definitions. */
 EXPORT_TRACEPOINT_SYMBOL(kmalloc);
 EXPORT_TRACEPOINT_SYMBOL(kmem_cache_alloc);