1 files changed, 17 insertions, 10 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index c19734d96d7e..943cc8b83e59 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4224,8 +4224,10 @@ static const struct ata_blacklist_entry ata_device_blacklist [] = {
         { "PIONEER DVD-RW  DVR-216D",   NULL,   ATA_HORKAGE_NOSETXFER },
 
         /* devices that don't properly handle queued TRIM commands */
-        { "Micron_M500*",               NULL,   ATA_HORKAGE_NO_NCQ_TRIM, },
-        { "Crucial_CT???M500SSD*",      NULL,   ATA_HORKAGE_NO_NCQ_TRIM, },
+        { "Micron_M500*",               "MU0[1-4]*",    ATA_HORKAGE_NO_NCQ_TRIM, },
+        { "Crucial_CT???M500SSD*",      "MU0[1-4]*",    ATA_HORKAGE_NO_NCQ_TRIM, },
+        { "Micron_M550*",               NULL,           ATA_HORKAGE_NO_NCQ_TRIM, },
+        { "Crucial_CT???M550SSD*",      NULL,           ATA_HORKAGE_NO_NCQ_TRIM, },
 
         /*
          * Some WD SATA-I drives spin up and down erratically when the link
@@ -4792,21 +4794,26 @@ void swap_buf_le16(u16 *buf, unsigned int buf_words)
 static struct ata_queued_cmd *ata_qc_new(struct ata_port *ap)
 {
         struct ata_queued_cmd *qc = NULL;
-        unsigned int i;
+        unsigned int i, tag;
 
         /* no command while frozen */
         if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))
                 return NULL;
 
-        /* the last tag is reserved for internal command. */
-        for (i = 0; i < ATA_MAX_QUEUE - 1; i++)
-                if (!test_and_set_bit(i, &ap->qc_allocated)) {
-                        qc = __ata_qc_from_tag(ap, i);
+        for (i = 0; i < ATA_MAX_QUEUE; i++) {
+                tag = (i + ap->last_tag + 1) % ATA_MAX_QUEUE;
+
+                /* the last tag is reserved for internal command. */
+                if (tag == ATA_TAG_INTERNAL)
+                        continue;
+
+                if (!test_and_set_bit(tag, &ap->qc_allocated)) {
+                        qc = __ata_qc_from_tag(ap, tag);
+                        qc->tag = tag;
+                        ap->last_tag = tag;
                         break;
                 }
-
-        if (qc)
-                qc->tag = i;
+        }
 
         return qc;
 }