mm: move sys_mmap_pgoff from util.c

Move sys_mmap_pgoff() from mm/util.c to mm/mmap.c and mm/nommu.c,
where we'd expect to find such code: especially now that it contains
the MAP_HUGETLB handling.  Revert mm/util.c to how it was in 2.6.32.

This patch just ignores MAP_HUGETLB in the nommu case, as in 2.6.32,
whereas 2.6.33-rc2 reported -ENOSYS.  Perhaps validate_mmap_request()
should reject it with -EINVAL?  Add that later if necessary.

Signed-off-by: Hugh Dickins <hugh.dickins@tiscali.co.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 65 insertions, 44 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index d9c77b2dbe9d..ee2298936fe6 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -1043,6 +1043,46 @@ unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
 }
 EXPORT_SYMBOL(do_mmap_pgoff);
 
+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;
+}
+
 /*
  * Some shared mappigns will want the pages marked read-only
  * to track write events. If so, we'll downgrade vm_page_prot
diff --git a/mm/nommu.c b/mm/nommu.c
index 8687973462bb..6f9248f89bde 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -1398,6 +1398,31 @@ error_getting_region:
 }
 EXPORT_SYMBOL(do_mmap_pgoff);
 
+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)) {
+                file = fget(fd);
+                if (!file)
+                        goto out;
+        }
+
+        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;
+}
+
 /*
  * split a vma into two pieces at address 'addr', a new vma is allocated either
  * for the first part or the tail.
diff --git a/mm/util.c b/mm/util.c
index b377ce430803..7c35ad95f927 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -4,10 +4,6 @@
 #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
@@ -272,46 +268,6 @@ 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);