ub: Ignore bad residue

[~andy/linux] / drivers / block / ub.c

diff --git a/drivers/block/ub.c b/drivers/block/ub.c
index b87ad77e5bb5522ddd5726467275d5ad77e3e5b5..e2c3ebd8db220e6911b1c7543bb280f15d80f119 100644 (file)
--- a/drivers/block/ub.c
+++ b/drivers/block/ub.c
@@ -319,6 +319,7 @@ struct ub_dev {
        int openc;                      /* protected by ub_lock! */
                                        /* kref is too implicit for our taste */
        int reset;                      /* Reset is running */
+       int bad_resid;
        unsigned int tagcnt;
        char name[12];
        struct usb_device *dev;
@@ -792,10 +793,6 @@ static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
                        scsi_status = 0;
                } else {
                        if (cmd->act_len != cmd->len) {
-                               if ((cmd->key == MEDIUM_ERROR ||
-                                    cmd->key == UNIT_ATTENTION) &&
-                                   ub_rw_cmd_retry(sc, lun, urq, cmd) == 0)
-                                       return;
                                scsi_status = SAM_STAT_CHECK_CONDITION;
                        } else {
                                scsi_status = 0;
@@ -811,7 +808,10 @@ static void ub_rw_cmd_done(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
                        else
                                scsi_status = DID_ERROR << 16;
                } else {
-                       if (cmd->error == -EIO) {
+                       if (cmd->error == -EIO &&
+                           (cmd->key == 0 ||
+                            cmd->key == MEDIUM_ERROR ||
+                            cmd->key == UNIT_ATTENTION)) {
                                if (ub_rw_cmd_retry(sc, lun, urq, cmd) == 0)
                                        return;
                        }
@@ -1266,14 +1266,19 @@ static void ub_scsi_urb_compl(struct ub_dev *sc, struct ub_scsi_cmd *cmd)
                        return;
                }
 
-               len = le32_to_cpu(bcs->Residue);
-               if (len != cmd->len - cmd->act_len) {
-                       /*
-                        * It is all right to transfer less, the caller has
-                        * to check. But it's not all right if the device
-                        * counts disagree with our counts.
-                        */
-                       goto Bad_End;
+               if (!sc->bad_resid) {
+                       len = le32_to_cpu(bcs->Residue);
+                       if (len != cmd->len - cmd->act_len) {
+                               /*
+                                * Only start ignoring if this cmd ended well.
+                                */
+                               if (cmd->len == cmd->act_len) {
+                                       printk(KERN_NOTICE "%s: "
+                                           "bad residual %d of %d, ignoring\n",
+                                           sc->name, len, cmd->len);
+                                       sc->bad_resid = 1;
+                               }
+                       }
                }
 
                switch (bcs->Status) {