netfs: Fix the pre-flush when appending to a file in writethrough mode

[linux-block.git] / fs / netfs / buffered_write.c

diff --git a/fs/netfs/buffered_write.c b/fs/netfs/buffered_write.c
index 9a0d32e4b422ad09518a6c6143638d0c68fb8b84..267b622d923b1fc63507300831c3163ba38d8a19 100644 (file)
--- a/fs/netfs/buffered_write.c
+++ b/fs/netfs/buffered_write.c
@@ -164,7 +164,7 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter,
        enum netfs_how_to_modify howto;
        enum netfs_folio_trace trace;
        unsigned int bdp_flags = (iocb->ki_flags & IOCB_SYNC) ? 0: BDP_ASYNC;
-       ssize_t written = 0, ret;
+       ssize_t written = 0, ret, ret2;
        loff_t i_size, pos = iocb->ki_pos, from, to;
        size_t max_chunk = PAGE_SIZE << MAX_PAGECACHE_ORDER;
        bool maybe_trouble = false;
@@ -172,15 +172,14 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter,
        if (unlikely(test_bit(NETFS_ICTX_WRITETHROUGH, &ctx->flags) ||
                     iocb->ki_flags & (IOCB_DSYNC | IOCB_SYNC))
            ) {
-               if (pos < i_size_read(inode)) {
-                       ret = filemap_write_and_wait_range(mapping, pos, pos + iter->count);
-                       if (ret < 0) {
-                               goto out;
-                       }
-               }
-
                wbc_attach_fdatawrite_inode(&wbc, mapping->host);
 
+               ret = filemap_write_and_wait_range(mapping, pos, pos + iter->count);
+               if (ret < 0) {
+                       wbc_detach_inode(&wbc);
+                       goto out;
+               }
+
                wreq = netfs_begin_writethrough(iocb, iter->count);
                if (IS_ERR(wreq)) {
                        wbc_detach_inode(&wbc);
@@ -395,10 +394,12 @@ ssize_t netfs_perform_write(struct kiocb *iocb, struct iov_iter *iter,
 
 out:
        if (unlikely(wreq)) {
-               ret = netfs_end_writethrough(wreq, iocb);
+               ret2 = netfs_end_writethrough(wreq, iocb);
                wbc_detach_inode(&wbc);
-               if (ret == -EIOCBQUEUED)
-                       return ret;
+               if (ret2 == -EIOCBQUEUED)
+                       return ret2;
+               if (ret == 0)
+                       ret = ret2;
        }
 
        iocb->ki_pos += written;