mmc: block: Add write packing control
The write packing control will ensure that read requests latency is
not increased due to long write packed commands.
The trigger for enabling the write packing is managing to pack several
write requests. The number of potential packed requests that will trigger
the packing can be configured via sysfs by writing the required value to:
/sys/block/<block_dev_name>/num_wr_reqs_to_start_packing.
The trigger for disabling the write packing is fetching a read request.
Change-Id: I22e8ab04cd9aca220678784c39306068a0996790
Signed-off-by: Maya Erez <merez@codeaurora.org>
Signed-off-by: Tatyana Brokhman <tlinder@codeaurora.org>
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 714cc76..9e536be 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -245,6 +245,8 @@
#define MMC_CAP2_PACKED_WR (1 << 11) /* Allow packed write */
#define MMC_CAP2_PACKED_CMD (MMC_CAP2_PACKED_RD | \
MMC_CAP2_PACKED_WR) /* Allow packed commands */
+#define MMC_CAP2_PACKED_WR_CONTROL (1 << 12) /* Allow write packing control */
+
#define MMC_CAP2_SANITIZE (1 << 13) /* Support Sanitize */
#define MMC_CAP2_INIT_BKOPS (1 << 15) /* Need to set BKOPS_EN */
#define MMC_CAP2_POWER_OFF_VCCQ_DURING_SUSPEND (1 << 16)