libata: add ATA_HORKAGE_NOTRIM

commit 71d126fd28de2d4d9b7b2088dbccd7ca62fad6e0 upstream.

Some devices lose data on TRIM whether queued or not.  This patch adds
a horkage to disable TRIM.

tj: Collapsed unnecessary if() nesting.

Signed-off-by: Arne Fitzenreiter <arne_f@ipfire.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
[bwh: Backported to 3.2:
 - Adjust context
 - Drop change to show_ata_dev_trim()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 8460e62..0ac7a5e 100644 (file)
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -2473,7 +2473,8 @@ static unsigned int ata_scsiop_read_cap(struct ata_scsi_args *args, u8 *rbuf)
                rbuf[14] = (lowest_aligned >> 8) & 0x3f;
                rbuf[15] = lowest_aligned;
 
-               if (ata_id_has_trim(args->id)) {
+               if (ata_id_has_trim(args->id) &&
+                   !(dev->horkage & ATA_HORKAGE_NOTRIM)) {
                        rbuf[14] |= 0x80; /* TPE */
 
                        if (ata_id_has_zero_after_trim(args->id))

diff --git a/include/linux/libata.h b/include/linux/libata.h
index 3d4b5b6..000434e 100644 (file)
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -403,6 +403,8 @@ enum {
        ATA_HORKAGE_MAX_SEC_LBA48 = (1 << 17),  /* Set max sects to 65535 */
        ATA_HORKAGE_NOLPM       = (1 << 20),    /* don't use LPM */
        ATA_HORKAGE_WD_BROKEN_LPM = (1 << 21),  /* some WDs have broken LPM */
+       ATA_HORKAGE_NOTRIM      = (1 << 24),    /* don't use TRIM */
+
 
         /* DMA mask for user DMA control: User visible values; DO NOT
            renumber */