iomap: don't report direct-io retries to fserror

iomap's directio implementation has two magic errno codes that it uses
to signal callers -- ENOTBLK tells the filesystem that it should retry
a write with the pagecache; and EAGAIN tells the caller that pagecache
flushing or invalidation failed and that it should try again.

Neither of these indicate data loss, so let's not report them.

Fixes: a9d573ee88af98 ("iomap: report file I/O errors to the VFS")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Link: https://patch.msgid.link/20260224154637.GD2390381@frogsfrogsfrogs
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
index 95254aa1b6546a4e30dae45f18d2a578eb4c5559..e911daedff65ae60ecb9b7f710ada6ddaefaf425 100644 (file)
--- a/fs/iomap/direct-io.c
+++ b/fs/iomap/direct-io.c
@@ -87,6 +87,19 @@ static inline enum fserror_type iomap_dio_err_type(const struct iomap_dio *dio)
        return FSERR_DIRECTIO_READ;
 }
 
+static inline bool should_report_dio_fserror(const struct iomap_dio *dio)
+{
+       switch (dio->error) {
+       case 0:
+       case -EAGAIN:
+       case -ENOTBLK:
+               /* don't send fsnotify for success or magic retry codes */
+               return false;
+       default:
+               return true;
+       }
+}
+
 ssize_t iomap_dio_complete(struct iomap_dio *dio)
 {
        const struct iomap_dio_ops *dops = dio->dops;
@@ -96,7 +109,7 @@ ssize_t iomap_dio_complete(struct iomap_dio *dio)
 
        if (dops && dops->end_io)
                ret = dops->end_io(iocb, dio->size, ret, dio->flags);
-       if (dio->error)
+       if (should_report_dio_fserror(dio))
                fserror_report_io(file_inode(iocb->ki_filp),
                                  iomap_dio_err_type(dio), offset, dio->size,
                                  dio->error, GFP_NOFS);