[PATCH 4.18 179/228] mmc: android-goldfish: fix bad logic of sg_copy_{from,to}_buffer conversion

From: Greg Kroah-Hartman
Date: Tue Oct 02 2018 - 10:01:37 EST


4.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Ludovic Desroches <ludovic.desroches@xxxxxxxxxxxxx>

[ Upstream commit 17e96d8516e31c3cb52cb8e2ee79d1d2e6948c11 ]

The conversion to sg_copy_{from,to}_buffer has been done in the wrong
way. sg_copy_to_buffer is a copy from an SG list to a linear buffer so
it can't replace memcpy(dest, host->virt_base, data->sg->length) where
dest is the virtual address of the SG. Same for sg_copy_from_buffer
but in the opposite way.

Signed-off-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxxxxxx>
Suggested-by: Douglas Gilbert <dgilbert@xxxxxxxxxxxx>
Fixes: 53d7e098ba08 ("mmc: android-goldfish: use sg_copy_{from,to}_buffer")
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/mmc/host/android-goldfish.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/mmc/host/android-goldfish.c
+++ b/drivers/mmc/host/android-goldfish.c
@@ -217,7 +217,7 @@ static void goldfish_mmc_xfer_done(struc
* We don't really have DMA, so we need
* to copy from our platform driver buffer
*/
- sg_copy_to_buffer(data->sg, 1, host->virt_base,
+ sg_copy_from_buffer(data->sg, 1, host->virt_base,
data->sg->length);
}
host->data->bytes_xfered += data->sg->length;
@@ -393,7 +393,7 @@ static void goldfish_mmc_prepare_data(st
* We don't really have DMA, so we need to copy to our
* platform driver buffer
*/
- sg_copy_from_buffer(data->sg, 1, host->virt_base,
+ sg_copy_to_buffer(data->sg, 1, host->virt_base,
data->sg->length);
}
}