Implement new aops for some of the simpler filesystems.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 
 static const struct address_space_operations configfs_aops = {
        .readpage       = simple_readpage,
-       .prepare_write  = simple_prepare_write,
-       .commit_write   = simple_commit_write
+       .write_begin    = simple_write_begin,
+       .write_end      = simple_write_end,
 };
 
 static struct backing_dev_info configfs_backing_dev_info = {
 
        return -EINVAL;
 }
 
-static int hugetlbfs_prepare_write(struct file *file,
-                       struct page *page, unsigned offset, unsigned to)
+static int hugetlbfs_write_begin(struct file *file,
+                       struct address_space *mapping,
+                       loff_t pos, unsigned len, unsigned flags,
+                       struct page **pagep, void **fsdata)
 {
        return -EINVAL;
 }
 
-static int hugetlbfs_commit_write(struct file *file,
-                       struct page *page, unsigned offset, unsigned to)
+static int hugetlbfs_write_end(struct file *file, struct address_space *mapping,
+                       loff_t pos, unsigned len, unsigned copied,
+                       struct page *page, void *fsdata)
 {
+       BUG();
        return -EINVAL;
 }
 
 
 static const struct address_space_operations hugetlbfs_aops = {
        .readpage       = hugetlbfs_readpage,
-       .prepare_write  = hugetlbfs_prepare_write,
-       .commit_write   = hugetlbfs_commit_write,
+       .write_begin    = hugetlbfs_write_begin,
+       .write_end      = hugetlbfs_write_end,
        .set_page_dirty = hugetlbfs_set_page_dirty,
 };
 
 
 
 const struct address_space_operations ramfs_aops = {
        .readpage       = simple_readpage,
-       .prepare_write  = simple_prepare_write,
-       .commit_write   = simple_commit_write,
+       .write_begin    = simple_write_begin,
+       .write_end      = simple_write_end,
        .set_page_dirty = __set_page_dirty_no_writeback,
 };
 
 
 
 const struct address_space_operations ramfs_aops = {
        .readpage               = simple_readpage,
-       .prepare_write          = simple_prepare_write,
-       .commit_write           = simple_commit_write,
+       .write_begin            = simple_write_begin,
+       .write_end              = simple_write_end,
        .set_page_dirty         = __set_page_dirty_no_writeback,
 };
 
 
 
 static const struct address_space_operations sysfs_aops = {
        .readpage       = simple_readpage,
-       .prepare_write  = simple_prepare_write,
-       .commit_write   = simple_commit_write
+       .write_begin    = simple_write_begin,
+       .write_end      = simple_write_end,
 };
 
 static struct backing_dev_info sysfs_backing_dev_info = {
 
         * Normally, filepage is NULL on entry, and either found
         * uptodate immediately, or allocated and zeroed, or read
         * in under swappage, which is then assigned to filepage.
-        * But shmem_readpage and shmem_prepare_write pass in a locked
+        * But shmem_readpage and shmem_write_begin pass in a locked
         * filepage, which may be found not uptodate by other callers
         * too, and may need to be copied from the swappage read in.
         */
 static const struct inode_operations shmem_symlink_inline_operations;
 
 /*
- * Normally tmpfs avoids the use of shmem_readpage and shmem_prepare_write;
+ * Normally tmpfs avoids the use of shmem_readpage and shmem_write_begin;
  * but providing them allows a tmpfs file to be used for splice, sendfile, and
  * below the loop driver, in the generic fashion that many filesystems support.
  */
 }
 
 static int
-shmem_prepare_write(struct file *file, struct page *page, unsigned offset, unsigned to)
+shmem_write_begin(struct file *file, struct address_space *mapping,
+                       loff_t pos, unsigned len, unsigned flags,
+                       struct page **pagep, void **fsdata)
 {
-       struct inode *inode = page->mapping->host;
-       return shmem_getpage(inode, page->index, &page, SGP_WRITE, NULL);
+       struct inode *inode = mapping->host;
+       pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+       *pagep = NULL;
+       return shmem_getpage(inode, index, pagep, SGP_WRITE, NULL);
+}
+
+static int
+shmem_write_end(struct file *file, struct address_space *mapping,
+                       loff_t pos, unsigned len, unsigned copied,
+                       struct page *page, void *fsdata)
+{
+       struct inode *inode = mapping->host;
+
+       set_page_dirty(page);
+       page_cache_release(page);
+
+       if (pos+copied > inode->i_size)
+               i_size_write(inode, pos+copied);
+
+       return copied;
 }
 
 static ssize_t
        .set_page_dirty = __set_page_dirty_no_writeback,
 #ifdef CONFIG_TMPFS
        .readpage       = shmem_readpage,
-       .prepare_write  = shmem_prepare_write,
-       .commit_write   = simple_commit_write,
+       .write_begin    = shmem_write_begin,
+       .write_end      = shmem_write_end,
 #endif
        .migratepage    = migrate_page,
 };