[PATCH v7 14/19] iomap: Fix iomap_dio_rw return value for user copies

From: Andreas Gruenbacher
Date: Fri Aug 27 2021 - 12:51:23 EST


When a user copy fails in one of the helpers of iomap_dio_rw, fail with
-EFAULT instead of returning 0. This matches what iomap_dio_bio_actor
returns when it gets an -EFAULT from bio_iov_iter_get_pages. With these
changes, iomap_dio_actor now consistently fails with -EFAULT when a user
page cannot be faulted in.

Signed-off-by: Andreas Gruenbacher <agruenba@xxxxxxxxxx>
---
fs/iomap/direct-io.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
index 9398b8c31323..8054f5d6c273 100644
--- a/fs/iomap/direct-io.c
+++ b/fs/iomap/direct-io.c
@@ -370,7 +370,7 @@ iomap_dio_hole_actor(loff_t length, struct iomap_dio *dio)
{
length = iov_iter_zero(length, dio->submit.iter);
dio->size += length;
- return length;
+ return length ? length : -EFAULT;
}

static loff_t
@@ -397,7 +397,7 @@ iomap_dio_inline_actor(struct inode *inode, loff_t pos, loff_t length,
copied = copy_to_iter(iomap->inline_data + pos, length, iter);
}
dio->size += copied;
- return copied;
+ return copied ? copied : -EFAULT;
}

static loff_t
--
2.26.3