From 8bff7c6b0f63c7ee9c5e3a076338d74125b8debb Mon Sep 17 00:00:00 2001
From: Jens Axboe <jens.axboe@oracle.com>
Date: Wed, 24 Sep 2008 13:05:10 +0200
Subject: [PATCH] libata: set queue SSD flag for SSD devices
SSD devices should give an RPM setting of 1 in word 217 of the ID
page. If we see such a device, tell the block layer about it.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
---
drivers/ata/libata-scsi.c | 4 ++++
include/linux/ata.h | 6 ++++++
2 files changed, 10 insertions(+)
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index b9d3ba423cb..054370700ab 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -977,6 +977,10 @@ static int ata_scsi_dev_config(struct scsi_device *sdev,
blk_queue_dma_drain(q, atapi_drain_needed, buf, ATAPI_MAX_DRAIN);
} else {
+ if (ata_id_is_ssd(dev->id))
+ queue_flag_set_unlocked(QUEUE_FLAG_NONROT,
+ sdev->request_queue);
+
/* ATA devices must be sector aligned */
blk_queue_update_dma_alignment(sdev->request_queue,
ATA_SECT_SIZE - 1);
diff --git a/include/linux/ata.h b/include/linux/ata.h
index 8a12d718c16..c1c8b4a4ba2 100644
--- a/include/linux/ata.h
+++ b/include/linux/ata.h
@@ -88,6 +88,7 @@ enum {
ATA_ID_DLF = 128,
ATA_ID_CSFO = 129,
ATA_ID_CFA_POWER = 160,
+ ATA_ID_ROT_SPEED = 217,
ATA_ID_PIO4 = (1 << 1),
ATA_ID_SERNO_LEN = 20,
@@ -691,6 +692,11 @@ static inline int ata_id_is_cfa(const u16 *id)
return 0;
}
+static inline int ata_id_is_ssd(const u16 *id)
+{
+ return id[ATA_ID_ROT_SPEED] == 0x01;
+}
+
static inline int ata_drive_40wire(const u16 *dev_id)
{
if (ata_id_is_sata(dev_id))
--
2.41.3