bcachefs: Use filemap_read() to simplify the execution flow

Using filemap_read() can reduce unnecessary code execution
for non IOCB_DIRECT paths.

Signed-off-by: Youling Tang <tangyouling@kylinos.cn>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

diff --git a/fs/bcachefs/fs-io-direct.c b/fs/bcachefs/fs-io-direct.c
index 049b61bc9a5b38e491c367d9a6b5a0f9c6567426..e246b1e05aa2bec932fedfeeda840a0623417acc 100644 (file)
--- a/fs/bcachefs/fs-io-direct.c
+++ b/fs/bcachefs/fs-io-direct.c
@@ -179,7 +179,7 @@ ssize_t bch2_read_iter(struct kiocb *iocb, struct iov_iter *iter)
        struct bch_inode_info *inode = file_bch_inode(file);
        struct address_space *mapping = file->f_mapping;
        size_t count = iov_iter_count(iter);
-       ssize_t ret;
+       ssize_t ret = 0;
 
        if (!count)
                return 0; /* skip atime */
@@ -205,7 +205,7 @@ ssize_t bch2_read_iter(struct kiocb *iocb, struct iov_iter *iter)
                        iocb->ki_pos += ret;
        } else {
                bch2_pagecache_add_get(inode);
-               ret = generic_file_read_iter(iocb, iter);
+               ret = filemap_read(iocb, iter, ret);
                bch2_pagecache_add_put(inode);
        }
 out: