fs: introduce write_begin, write_end, and perform_write aops
[linux-2.6.git] / fs / splice.c
index 2df6be4..a7568bc 100644 (file)
@@ -563,7 +563,7 @@ static int pipe_to_file(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
        struct address_space *mapping = file->f_mapping;
        unsigned int offset, this_len;
        struct page *page;
-       pgoff_t index;
+       void *fsdata;
        int ret;
 
        /*
@@ -573,49 +573,16 @@ static int pipe_to_file(struct pipe_inode_info *pipe, struct pipe_buffer *buf,
        if (unlikely(ret))
                return ret;
 
-       index = sd->pos >> PAGE_CACHE_SHIFT;
        offset = sd->pos & ~PAGE_CACHE_MASK;
 
        this_len = sd->len;
        if (this_len + offset > PAGE_CACHE_SIZE)
                this_len = PAGE_CACHE_SIZE - offset;
 
-find_page:
-       page = find_lock_page(mapping, index);
-       if (!page) {
-               ret = -ENOMEM;
-               page = page_cache_alloc_cold(mapping);
-               if (unlikely(!page))
-                       goto out_ret;
-
-               /*
-                * This will also lock the page
-                */
-               ret = add_to_page_cache_lru(page, mapping, index,
-                                           GFP_KERNEL);
-               if (unlikely(ret))
-                       goto out_release;
-       }
-
-       ret = mapping->a_ops->prepare_write(file, page, offset, offset+this_len);
-       if (unlikely(ret)) {
-               loff_t isize = i_size_read(mapping->host);
-
-               if (ret != AOP_TRUNCATED_PAGE)
-                       unlock_page(page);
-               page_cache_release(page);
-               if (ret == AOP_TRUNCATED_PAGE)
-                       goto find_page;
-
-               /*
-                * prepare_write() may have instantiated a few blocks
-                * outside i_size.  Trim these off again.
-                */
-               if (sd->pos + this_len > isize)
-                       vmtruncate(mapping->host, isize);
-
-               goto out_ret;
-       }
+       ret = pagecache_write_begin(file, mapping, sd->pos, this_len,
+                               AOP_FLAG_UNINTERRUPTIBLE, &page, &fsdata);
+       if (unlikely(ret))
+               goto out;
 
        if (buf->page != page) {
                /*
@@ -629,31 +596,9 @@ find_page:
                kunmap_atomic(dst, KM_USER1);
                buf->ops->unmap(pipe, buf, src);
        }
-
-       ret = mapping->a_ops->commit_write(file, page, offset, offset+this_len);
-       if (ret) {
-               if (ret == AOP_TRUNCATED_PAGE) {
-                       page_cache_release(page);
-                       goto find_page;
-               }
-               if (ret < 0)
-                       goto out;
-               /*
-                * Partial write has happened, so 'ret' already initialized by
-                * number of bytes written, Where is nothing we have to do here.
-                */
-       } else
-               ret = this_len;
-       /*
-        * Return the number of bytes written and mark page as
-        * accessed, we are now done!
-        */
-       mark_page_accessed(page);
+       ret = pagecache_write_end(file, mapping, sd->pos, this_len, this_len,
+                               page, fsdata);
 out:
-       unlock_page(page);
-out_release:
-       page_cache_release(page);
-out_ret:
        return ret;
 }