[PATCH 4.19 014/425] mmc: block: Update ext_csd.cache_ctrl if it was written

From: Greg Kroah-Hartman
Date: Thu May 20 2021 - 05:36:28 EST


From: Avri Altman <avri.altman@xxxxxxx>

commit aea0440ad023ab0662299326f941214b0d7480bd upstream.

The cache function can be turned ON and OFF by writing to the CACHE_CTRL
byte (EXT_CSD byte [33]). However, card->ext_csd.cache_ctrl is only
set on init if cache size > 0.

Fix that by explicitly setting ext_csd.cache_ctrl on ext-csd write.

Signed-off-by: Avri Altman <avri.altman@xxxxxxx>
Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20210420134641.57343-3-avri.altman@xxxxxxx
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/mmc/core/block.c | 12 ++++++++++++
1 file changed, 12 insertions(+)

--- a/drivers/mmc/core/block.c
+++ b/drivers/mmc/core/block.c
@@ -623,6 +623,18 @@ static int __mmc_blk_ioctl_cmd(struct mm
}

/*
+ * Make sure to update CACHE_CTRL in case it was changed. The cache
+ * will get turned back on if the card is re-initialized, e.g.
+ * suspend/resume or hw reset in recovery.
+ */
+ if ((MMC_EXTRACT_INDEX_FROM_ARG(cmd.arg) == EXT_CSD_CACHE_CTRL) &&
+ (cmd.opcode == MMC_SWITCH)) {
+ u8 value = MMC_EXTRACT_VALUE_FROM_ARG(cmd.arg) & 1;
+
+ card->ext_csd.cache_ctrl = value;
+ }
+
+ /*
* According to the SD specs, some commands require a delay after
* issuing the command.
*/