libata: add ATA_HORKAGE_MAX_SEC_1024 to revert back to previous max_sectors limit

Since no longer limiting max_sectors to BLK_DEF_MAX_SECTORS (commit 34b48db66e08),
data corruption may occur on ST380013AS drive configured on 82801JI (ICH10 Family)
SATA controller. This patch will allow the driver to limit max_sectors as before

 # cat /sys/block/sdb/queue/max_sectors_kb
 512

I was able to double the max_sectors_kb value up to 16384 on linux-4.2.0-rc2
before seeing corruption, but seems safer to use previous limit. Without this
patch max_sectors_kb will be 32767.

tj: Minor comment update.

Reported-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: David Milburn <dmilburn@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org # v3.19 and later
Fixes: 34b48db66e08 ("block: remove artifical max_hw_sectors cap")

3 files changed, 12 insertions, 1 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index ed2b218ea64d..68202a8a3a0b 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -2478,6 +2478,10 @@ int ata_dev_configure(struct ata_device *dev)
                 dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_128,
                                          dev->max_sectors);
 
+        if (dev->horkage & ATA_HORKAGE_MAX_SEC_1024)
+                dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_1024,
+                                         dev->max_sectors);
+
         if (dev->horkage & ATA_HORKAGE_MAX_SEC_LBA48)
                 dev->max_sectors = ATA_MAX_SECTORS_LBA48;
 
@@ -4146,6 +4150,12 @@ static const struct ata_blacklist_entry ata_device_blacklist [] = {
         { "Slimtype DVD A  DS8A8SH", NULL,      ATA_HORKAGE_MAX_SEC_LBA48 },
         { "Slimtype DVD A  DS8A9SH", NULL,      ATA_HORKAGE_MAX_SEC_LBA48 },
 
+        /*
+         * Causes silent data corruption with higher max sects.
+         * http://lkml.kernel.org/g/x49wpy40ysk.fsf@segfault.boston.devel.redhat.com
+         */
+        { "ST380013AS",         "3.20",         ATA_HORKAGE_MAX_SEC_1024 },
+
         /* Devices we expect to fail diagnostics */
 
         /* Devices where NCQ should be avoided */
diff --git a/include/linux/ata.h b/include/linux/ata.h
index fed36418dd1c..6c78956aa470 100644
--- a/include/linux/ata.h
+++ b/include/linux/ata.h
@@ -45,6 +45,7 @@ enum {
         ATA_SECT_SIZE           = 512,
         ATA_MAX_SECTORS_128     = 128,
         ATA_MAX_SECTORS         = 256,
+        ATA_MAX_SECTORS_1024    = 1024,
         ATA_MAX_SECTORS_LBA48   = 65535,/* TODO: 65536? */
         ATA_MAX_SECTORS_TAPE    = 65535,
 
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 5c8bac6225a6..c9cfbcdb8d14 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -432,7 +432,7 @@ enum {
         ATA_HORKAGE_ZERO_AFTER_TRIM = (1 << 22),/* guarantees zero after trim */
         ATA_HORKAGE_NO_NCQ_LOG  = (1 << 23),    /* don't use NCQ for log read */
         ATA_HORKAGE_NOTRIM      = (1 << 24),    /* don't use TRIM */
-
+        ATA_HORKAGE_MAX_SEC_1024 = (1 << 25),   /* Limit max sects to 1024 */
 
          /* DMA mask for user DMA control: User visible values; DO NOT
             renumber */