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>

7 files changed, 5 insertions, 91 deletions

diff --git a/arch/x86/ia32/ia32entry.S b/arch/x86/ia32/ia32entry.S
index 581b0568fe19..5294d8446732 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 9f5527198825..016218c353e7 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 72a6dcd1299b..77c1184bee43 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 372b76edd63f..1bb6e395881c 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 1884a8d12bfa..dee1ff7cba58 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 45e00eb09c3a..8aa2057efd12 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 0157cd26d7cc..76d70a451285 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 */