Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

Pull SCSI fixes from James Bottomley:

 - a couple of serious fixes: use after free and blacklist for WRITE
   SAME

 - one error leg fix: write_pending failure

 - one user experience problem: do not override max_sectors_kb

 - one minor unused function removal

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: ibmvscsis: Fix write_pending failure path
  scsi: libiscsi: Remove iscsi_destroy_session
  scsi: libiscsi: Fix use-after-free race during iscsi_session_teardown
  scsi: sd: Do not override max_sectors_kb sysfs setting
  scsi: sd: Implement blacklist option for WRITE SAME w/ UNMAP

8 files changed, 36 insertions, 31 deletions

diff --git a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c
index 785fb42f6650..2799a6b08f73 100644
--- a/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c
+++ b/drivers/scsi/ibmvscsi_tgt/ibmvscsi_tgt.c
@@ -3767,7 +3767,7 @@ static int ibmvscsis_write_pending(struct se_cmd *se_cmd)
          */
         if ((vscsi->flags & (CLIENT_FAILED | RESPONSE_Q_DOWN))) {
                 pr_err("write_pending failed since: %d\n", vscsi->flags);
-                return 0;
+                return -EIO;
         }
 
         rc = srp_transfer_data(cmd, &vio_iu(iue)->srp.cmd, ibmvscsis_rdma,
diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index bd4605a34f54..c62e8d111fd9 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -2851,9 +2851,6 @@ EXPORT_SYMBOL_GPL(iscsi_session_setup);
 /**
  * iscsi_session_teardown - destroy session, host, and cls_session
  * @cls_session: iscsi session
- *
- * The driver must have called iscsi_remove_session before
- * calling this.
  */
 void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
 {
@@ -2863,6 +2860,8 @@ void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
 
         iscsi_pool_free(&session->cmdpool);
 
+        iscsi_remove_session(cls_session);
+
         kfree(session->password);
         kfree(session->password_in);
         kfree(session->username);
@@ -2877,7 +2876,8 @@ void iscsi_session_teardown(struct iscsi_cls_session *cls_session)
         kfree(session->portal_type);
         kfree(session->discovery_parent_type);
 
-        iscsi_destroy_session(cls_session);
+        iscsi_free_session(cls_session);
+
         iscsi_host_dec_session_cnt(shost);
         module_put(owner);
 }
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index e7818afeda2b..15590a063ad9 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -956,6 +956,9 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
         if (*bflags & BLIST_NO_DIF)
                 sdev->no_dif = 1;
 
+        if (*bflags & BLIST_UNMAP_LIMIT_WS)
+                sdev->unmap_limit_for_ws = 1;
+
         sdev->eh_timeout = SCSI_DEFAULT_EH_TIMEOUT;
 
         if (*bflags & BLIST_TRY_VPD_PAGES)
diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c
index 0190aeff5f7f..7404d26895f5 100644
--- a/drivers/scsi/scsi_transport_iscsi.c
+++ b/drivers/scsi/scsi_transport_iscsi.c
@@ -2211,22 +2211,6 @@ void iscsi_free_session(struct iscsi_cls_session *session)
 EXPORT_SYMBOL_GPL(iscsi_free_session);
 
 /**
- * iscsi_destroy_session - destroy iscsi session
- * @session: iscsi_session
- *
- * Can be called by a LLD or iscsi_transport. There must not be
- * any running connections.
- */
-int iscsi_destroy_session(struct iscsi_cls_session *session)
-{
-        iscsi_remove_session(session);
-        ISCSI_DBG_TRANS_SESSION(session, "Completing session destruction\n");
-        iscsi_free_session(session);
-        return 0;
-}
-EXPORT_SYMBOL_GPL(iscsi_destroy_session);
-
-/**
  * iscsi_create_conn - create iscsi class connection
  * @session: iscsi cls session
  * @dd_size: private driver data size
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index fb9f8b5f4673..d175c5c5ccf8 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -715,13 +715,21 @@ static void sd_config_discard(struct scsi_disk *sdkp, unsigned int mode)
                 break;
 
         case SD_LBP_WS16:
-                max_blocks = min_not_zero(sdkp->max_ws_blocks,
-                                          (u32)SD_MAX_WS16_BLOCKS);
+                if (sdkp->device->unmap_limit_for_ws)
+                        max_blocks = sdkp->max_unmap_blocks;
+                else
+                        max_blocks = sdkp->max_ws_blocks;
+
+                max_blocks = min_not_zero(max_blocks, (u32)SD_MAX_WS16_BLOCKS);
                 break;
 
         case SD_LBP_WS10:
-                max_blocks = min_not_zero(sdkp->max_ws_blocks,
-                                          (u32)SD_MAX_WS10_BLOCKS);
+                if (sdkp->device->unmap_limit_for_ws)
+                        max_blocks = sdkp->max_unmap_blocks;
+                else
+                        max_blocks = sdkp->max_ws_blocks;
+
+                max_blocks = min_not_zero(max_blocks, (u32)SD_MAX_WS10_BLOCKS);
                 break;
 
         case SD_LBP_ZERO:
@@ -3099,8 +3107,6 @@ static int sd_revalidate_disk(struct gendisk *disk)
                 sd_read_security(sdkp, buffer);
         }
 
-        sdkp->first_scan = 0;
-
         /*
          * We now have all cache related info, determine how we deal
          * with flush requests.
@@ -3115,7 +3121,7 @@ static int sd_revalidate_disk(struct gendisk *disk)
         q->limits.max_dev_sectors = logical_to_sectors(sdp, dev_max);
 
         /*
-         * Use the device's preferred I/O size for reads and writes
+         * Determine the device's preferred I/O size for reads and writes
          * unless the reported value is unreasonably small, large, or
          * garbage.
          */
@@ -3129,8 +3135,19 @@ static int sd_revalidate_disk(struct gendisk *disk)
                 rw_max = min_not_zero(logical_to_sectors(sdp, dev_max),
                                       (sector_t)BLK_DEF_MAX_SECTORS);
 
-        /* Combine with controller limits */
-        q->limits.max_sectors = min(rw_max, queue_max_hw_sectors(q));
+        /* Do not exceed controller limit */
+        rw_max = min(rw_max, queue_max_hw_sectors(q));
+
+        /*
+         * Only update max_sectors if previously unset or if the current value
+         * exceeds the capabilities of the hardware.
+         */
+        if (sdkp->first_scan ||
+            q->limits.max_sectors > q->limits.max_dev_sectors ||
+            q->limits.max_sectors > q->limits.max_hw_sectors)
+                q->limits.max_sectors = rw_max;
+
+        sdkp->first_scan = 0;
 
         set_capacity(disk, logical_to_sectors(sdp, sdkp->capacity));
         sd_config_write_same(sdkp);
diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h
index 82e93ee94708..67c5a9f223f7 100644
--- a/include/scsi/scsi_device.h
+++ b/include/scsi/scsi_device.h
@@ -192,6 +192,7 @@ struct scsi_device {
         unsigned no_dif:1;      /* T10 PI (DIF) should be disabled */
         unsigned broken_fua:1;          /* Don't set FUA bit */
         unsigned lun_in_cdb:1;          /* Store LUN bits in CDB[1] */
+        unsigned unmap_limit_for_ws:1;  /* Use the UNMAP limit for WRITE SAME */
 
         atomic_t disk_events_disable_depth; /* disable depth for disk events */
 
diff --git a/include/scsi/scsi_devinfo.h b/include/scsi/scsi_devinfo.h
index 9592570e092a..36b03013d629 100644
--- a/include/scsi/scsi_devinfo.h
+++ b/include/scsi/scsi_devinfo.h
@@ -29,5 +29,6 @@
 #define BLIST_TRY_VPD_PAGES     0x10000000 /* Attempt to read VPD pages */
 #define BLIST_NO_RSOC           0x20000000 /* don't try to issue RSOC */
 #define BLIST_MAX_1024          0x40000000 /* maximum 1024 sector cdb length */
+#define BLIST_UNMAP_LIMIT_WS    0x80000000 /* Use UNMAP limit for WRITE SAME */
 
 #endif
diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h
index 6183d20a01fb..b266d2a3bcb1 100644
--- a/include/scsi/scsi_transport_iscsi.h
+++ b/include/scsi/scsi_transport_iscsi.h
@@ -434,7 +434,6 @@ extern struct iscsi_cls_session *iscsi_create_session(struct Scsi_Host *shost,
                                                 unsigned int target_id);
 extern void iscsi_remove_session(struct iscsi_cls_session *session);
 extern void iscsi_free_session(struct iscsi_cls_session *session);
-extern int iscsi_destroy_session(struct iscsi_cls_session *session);
 extern struct iscsi_cls_conn *iscsi_create_conn(struct iscsi_cls_session *sess,
                                                 int dd_size, uint32_t cid);
 extern int iscsi_destroy_conn(struct iscsi_cls_conn *conn);