ext2fs: add readahead method to improve scanning

[tools/e2fsprogs.git] / lib / ext2fs / ext2_io.h

diff --git a/lib/ext2fs/ext2_io.h b/lib/ext2fs/ext2_io.h
index 1894fb8..4c5a5c5 100644 (file)
--- a/lib/ext2fs/ext2_io.h
+++ b/lib/ext2fs/ext2_io.h
@@ -90,7 +90,10 @@ struct struct_io_manager {
                                        int count, const void *data);
        errcode_t (*discard)(io_channel channel, unsigned long long block,
                             unsigned long long count);
-       long    reserved[16];
+       errcode_t (*cache_readahead)(io_channel channel,
+                                    unsigned long long block,
+                                    unsigned long long count);
+       long    reserved[15];
 };
 
 #define IO_FLAG_RW             0x0001
@@ -124,6 +127,9 @@ extern errcode_t io_channel_discard(io_channel channel,
                                    unsigned long long count);
 extern errcode_t io_channel_alloc_buf(io_channel channel,
                                      int count, void *ptr);
+extern errcode_t io_channel_cache_readahead(io_channel io,
+                                           unsigned long long block,
+                                           unsigned long long count);
 
 /* unix_io.c */
 extern io_manager unix_io_manager;