Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending

Pull SCSI target updates from Nicholas Bellinger:
 "It's been a busy development cycle for target-core in a number of
  different areas.

  The fabric API usage for se_node_acl allocation is now within
  target-core code, dropping the external API callers for all fabric
  drivers tree-wide.

  There is a new conversion to RCU hlists for se_node_acl and
  se_portal_group LUN mappings, that turns fast-past LUN lookup into a
  completely lockless code-path.  It also removes the original
  hard-coded limitation of 256 LUNs per fabric endpoint.

  The configfs attributes for backends can now be shared between core
  and driver code, allowing existing drivers to use common code while
  still allowing flexibility for new backend provided attributes.

  The highlights include:

   - Merge sbc_verify_dif_* into common code (sagi)
   - Remove iscsi-target support for obsolete IFMarker/OFMarker
     (Christophe Vu-Brugier)
   - Add bidi support in target/user backend (ilias + vangelis + agover)
   - Move se_node_acl allocation into target-core code (hch)
   - Add crc_t10dif_update common helper (akinobu + mkp)
   - Handle target-core odd SGL mapping for data transfer memory
     (akinobu)
   - Move transport ID handling into target-core (hch)
   - Move task tag into struct se_cmd + support 64-bit tags (bart)
   - Convert se_node_acl->device_list[] to RCU hlist (nab + hch +
     paulmck)
   - Convert se_portal_group->tpg_lun_list[] to RCU hlist (nab + hch +
     paulmck)
   - Simplify target backend driver registration (hch)
   - Consolidate + simplify target backend attribute implementations
     (hch + nab)
   - Subsume se_port + t10_alua_tg_pt_gp_member into se_lun (hch)
   - Drop lun_sep_lock for se_lun->lun_se_dev RCU usage (hch + nab)
   - Drop unnecessary core_tpg_register TFO parameter (nab)
   - Use 64-bit LUNs tree-wide (hannes)
   - Drop left-over TARGET_MAX_LUNS_PER_TRANSPORT limit (hannes)"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (76 commits)
  target: Bump core version to v5.0
  target: remove target_core_configfs.h
  target: remove unused TARGET_CORE_CONFIG_ROOT define
  target: consolidate version defines
  target: implement WRITE_SAME with UNMAP bit using ->execute_unmap
  target: simplify UNMAP handling
  target: replace se_cmd->execute_rw with a protocol_data field
  target/user: Fix inconsistent kmap_atomic/kunmap_atomic
  target: Send UA when changing LUN inventory
  target: Send UA upon LUN RESET tmr completion
  target: Send UA on ALUA target port group change
  target: Convert se_lun->lun_deve_lock to normal spinlock
  target: use 'se_dev_entry' when allocating UAs
  target: Remove 'ua_nacl' pointer from se_ua structure
  target_core_alua: Correct UA handling when switching states
  xen-scsiback: Fix compile warning for 64-bit LUN
  target: Remove TARGET_MAX_LUNS_PER_TRANSPORT
  target: use 64-bit LUNs
  target: Drop duplicate + unused se_dev_check_wce
  target: Drop unnecessary core_tpg_register TFO parameter
  ...

1 files changed, 50 insertions, 31 deletions

diff --git a/drivers/target/target_core_ua.c b/drivers/target/target_core_ua.c
index e44cc94b12cb..be25eb807a5f 100644
--- a/drivers/target/target_core_ua.c
+++ b/drivers/target/target_core_ua.c
@@ -29,7 +29,6 @@
 
 #include <target/target_core_base.h>
 #include <target/target_core_fabric.h>
-#include <target/target_core_configfs.h>
 
 #include "target_core_internal.h"
 #include "target_core_alua.h"
@@ -50,9 +49,17 @@ target_scsi3_ua_check(struct se_cmd *cmd)
         if (!nacl)
                 return 0;
 
-        deve = nacl->device_list[cmd->orig_fe_lun];
-        if (!atomic_read(&deve->ua_count))
+        rcu_read_lock();
+        deve = target_nacl_find_deve(nacl, cmd->orig_fe_lun);
+        if (!deve) {
+                rcu_read_unlock();
                 return 0;
+        }
+        if (!atomic_read(&deve->ua_count)) {
+                rcu_read_unlock();
+                return 0;
+        }
+        rcu_read_unlock();
         /*
          * From sam4r14, section 5.14 Unit attention condition:
          *
@@ -79,18 +86,11 @@ target_scsi3_ua_check(struct se_cmd *cmd)
 }
 
 int core_scsi3_ua_allocate(
-        struct se_node_acl *nacl,
-        u32 unpacked_lun,
+        struct se_dev_entry *deve,
         u8 asc,
         u8 ascq)
 {
-        struct se_dev_entry *deve;
         struct se_ua *ua, *ua_p, *ua_tmp;
-        /*
-         * PASSTHROUGH OPS
-         */
-        if (!nacl)
-                return -EINVAL;
 
         ua = kmem_cache_zalloc(se_ua_cache, GFP_ATOMIC);
         if (!ua) {
@@ -99,13 +99,9 @@ int core_scsi3_ua_allocate(
         }
         INIT_LIST_HEAD(&ua->ua_nacl_list);
 
-        ua->ua_nacl = nacl;
         ua->ua_asc = asc;
         ua->ua_ascq = ascq;
 
-        spin_lock_irq(&nacl->device_list_lock);
-        deve = nacl->device_list[unpacked_lun];
-
         spin_lock(&deve->ua_lock);
         list_for_each_entry_safe(ua_p, ua_tmp, &deve->ua_list, ua_nacl_list) {
                 /*
@@ -113,7 +109,6 @@ int core_scsi3_ua_allocate(
                  */
                 if ((ua_p->ua_asc == asc) && (ua_p->ua_ascq == ascq)) {
                         spin_unlock(&deve->ua_lock);
-                        spin_unlock_irq(&nacl->device_list_lock);
                         kmem_cache_free(se_ua_cache, ua);
                         return 0;
                 }
@@ -158,24 +153,40 @@ int core_scsi3_ua_allocate(
                         list_add_tail(&ua->ua_nacl_list,
                                 &deve->ua_list);
                 spin_unlock(&deve->ua_lock);
-                spin_unlock_irq(&nacl->device_list_lock);
 
                 atomic_inc_mb(&deve->ua_count);
                 return 0;
         }
         list_add_tail(&ua->ua_nacl_list, &deve->ua_list);
         spin_unlock(&deve->ua_lock);
-        spin_unlock_irq(&nacl->device_list_lock);
 
-        pr_debug("[%s]: Allocated UNIT ATTENTION, mapped LUN: %u, ASC:"
-                " 0x%02x, ASCQ: 0x%02x\n",
-                nacl->se_tpg->se_tpg_tfo->get_fabric_name(), unpacked_lun,
+        pr_debug("Allocated UNIT ATTENTION, mapped LUN: %llu, ASC:"
+                " 0x%02x, ASCQ: 0x%02x\n", deve->mapped_lun,
                 asc, ascq);
 
         atomic_inc_mb(&deve->ua_count);
         return 0;
 }
 
+void target_ua_allocate_lun(struct se_node_acl *nacl,
+                            u32 unpacked_lun, u8 asc, u8 ascq)
+{
+        struct se_dev_entry *deve;
+
+        if (!nacl)
+                return;
+
+        rcu_read_lock();
+        deve = target_nacl_find_deve(nacl, unpacked_lun);
+        if (!deve) {
+                rcu_read_unlock();
+                return;
+        }
+
+        core_scsi3_ua_allocate(deve, asc, ascq);
+        rcu_read_unlock();
+}
+
 void core_scsi3_ua_release_all(
         struct se_dev_entry *deve)
 {
@@ -210,10 +221,14 @@ void core_scsi3_ua_for_check_condition(
         if (!nacl)
                 return;
 
-        spin_lock_irq(&nacl->device_list_lock);
-        deve = nacl->device_list[cmd->orig_fe_lun];
+        rcu_read_lock();
+        deve = target_nacl_find_deve(nacl, cmd->orig_fe_lun);
+        if (!deve) {
+                rcu_read_unlock();
+                return;
+        }
         if (!atomic_read(&deve->ua_count)) {
-                spin_unlock_irq(&nacl->device_list_lock);
+                rcu_read_unlock();
                 return;
         }
         /*
@@ -249,10 +264,10 @@ void core_scsi3_ua_for_check_condition(
                 atomic_dec_mb(&deve->ua_count);
         }
         spin_unlock(&deve->ua_lock);
-        spin_unlock_irq(&nacl->device_list_lock);
+        rcu_read_unlock();
 
         pr_debug("[%s]: %s UNIT ATTENTION condition with"
-                " INTLCK_CTRL: %d, mapped LUN: %u, got CDB: 0x%02x"
+                " INTLCK_CTRL: %d, mapped LUN: %llu, got CDB: 0x%02x"
                 " reported ASC: 0x%02x, ASCQ: 0x%02x\n",
                 nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
                 (dev->dev_attrib.emulate_ua_intlck_ctrl != 0) ? "Reporting" :
@@ -278,10 +293,14 @@ int core_scsi3_ua_clear_for_request_sense(
         if (!nacl)
                 return -EINVAL;
 
-        spin_lock_irq(&nacl->device_list_lock);
-        deve = nacl->device_list[cmd->orig_fe_lun];
+        rcu_read_lock();
+        deve = target_nacl_find_deve(nacl, cmd->orig_fe_lun);
+        if (!deve) {
+                rcu_read_unlock();
+                return -EINVAL;
+        }
         if (!atomic_read(&deve->ua_count)) {
-                spin_unlock_irq(&nacl->device_list_lock);
+                rcu_read_unlock();
                 return -EPERM;
         }
         /*
@@ -307,10 +326,10 @@ int core_scsi3_ua_clear_for_request_sense(
                 atomic_dec_mb(&deve->ua_count);
         }
         spin_unlock(&deve->ua_lock);
-        spin_unlock_irq(&nacl->device_list_lock);
+        rcu_read_unlock();
 
         pr_debug("[%s]: Released UNIT ATTENTION condition, mapped"
-                " LUN: %u, got REQUEST_SENSE reported ASC: 0x%02x,"
+                " LUN: %llu, got REQUEST_SENSE reported ASC: 0x%02x,"
                 " ASCQ: 0x%02x\n", nacl->se_tpg->se_tpg_tfo->get_fabric_name(),
                 cmd->orig_fe_lun, *asc, *ascq);