[PATCH] filemap.c bits for uClinux

Without CONFIG_MMU we don't need to stub out mmap().  Move one function
around inside filemap.c to need just one ifdef.

diff --git a/mm/filemap.c b/mm/filemap.c
index cb31b54fb61bb1f2e45adac92db75e3309a11729..3786795efd69ba87c096f87ad73e538299b980cb 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -9,6 +9,7 @@
  * most "normal" filesystems (but you don't /have/ to use this:
  * the NFS filesystem used to do this differently, for example)
  */
+#include <linux/config.h>
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/compiler.h>
@@ -247,37 +248,6 @@ int add_to_page_cache_lru(struct page *page,
        return ret;
 }
 
-/*
- * This adds the requested page to the page cache if it isn't already there,
- * and schedules an I/O to read in its contents from disk.
- */
-static int FASTCALL(page_cache_read(struct file * file, unsigned long offset));
-static int page_cache_read(struct file * file, unsigned long offset)
-{
-       struct address_space *mapping = file->f_dentry->d_inode->i_mapping;
-       struct page *page; 
-       int error;
-
-       page = page_cache_alloc_cold(mapping);
-       if (!page)
-               return -ENOMEM;
-
-       error = add_to_page_cache_lru(page, mapping, offset);
-       if (!error) {
-               error = mapping->a_ops->readpage(file, page);
-               page_cache_release(page);
-               return error;
-       }
-
-       /*
-        * We arrive here in the unlikely event that someone 
-        * raced with us and added our page to the cache first
-        * or we are out of memory for radix-tree nodes.
-        */
-       page_cache_release(page);
-       return error == -EEXIST ? 0 : error;
-}
-
 /*
  * In order to wait for pages to become available there must be
  * waitqueues associated with pages. By using a hash table of
@@ -978,6 +948,38 @@ asmlinkage ssize_t sys_readahead(int fd, loff_t offset, size_t count)
        return ret;
 }
 
+#ifdef CONFIG_MMU
+/*
+ * This adds the requested page to the page cache if it isn't already there,
+ * and schedules an I/O to read in its contents from disk.
+ */
+static int FASTCALL(page_cache_read(struct file * file, unsigned long offset));
+static int page_cache_read(struct file * file, unsigned long offset)
+{
+       struct address_space *mapping = file->f_dentry->d_inode->i_mapping;
+       struct page *page; 
+       int error;
+
+       page = page_cache_alloc_cold(mapping);
+       if (!page)
+               return -ENOMEM;
+
+       error = add_to_page_cache_lru(page, mapping, offset);
+       if (!error) {
+               error = mapping->a_ops->readpage(file, page);
+               page_cache_release(page);
+               return error;
+       }
+
+       /*
+        * We arrive here in the unlikely event that someone 
+        * raced with us and added our page to the cache first
+        * or we are out of memory for radix-tree nodes.
+        */
+       page_cache_release(page);
+       return error == -EEXIST ? 0 : error;
+}
+
 /*
  * filemap_nopage() is invoked via the vma operations vector for a
  * mapped memory region to read in file data during a page fault.
@@ -986,7 +988,6 @@ asmlinkage ssize_t sys_readahead(int fd, loff_t offset, size_t count)
  * it in the page cache, and handles the special cases reasonably without
  * having a lot of duplicated code.
  */
-
 struct page * filemap_nopage(struct vm_area_struct * area, unsigned long address, int unused)
 {
        int error;
@@ -1320,6 +1321,12 @@ int generic_file_mmap(struct file * file, struct vm_area_struct * vma)
        vma->vm_ops = &generic_file_vm_ops;
        return 0;
 }
+#else
+int generic_file_mmap(struct file * file, struct vm_area_struct * vma)
+{
+       return -ENOSYS;
+}
+#endif /* CONFIG_MMU */
 
 static inline struct page *__read_cache_page(struct address_space *mapping,
                                unsigned long index,