1. 01 Jun, 2015 9 commits
    • Nicholas Bellinger's avatar
      target: Only reset specific dynamic entries during lun_group creation · df9766ca
      Nicholas Bellinger authored
      This patch changes core_tpg_add_node_to_devs() to avoid unnecessarly
      resetting every se_dev_entry in se_node_acl->tpg_lun_hlist when the
      operation is driven by an explicit configfs se_lun->lun_group creation
      via core_dev_add_lun() to only update a single se_lun.
      
      Otherwise for the second core_tpg_check_initiator_node_acl() case, go
      ahead and continue to scan the full set of currently active se_lun in
      se_portal_group->tpg_lun_hlist.
      Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Sagi Grimberg <sagig@mellanox.com>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      df9766ca
    • Nicholas Bellinger's avatar
      target: Drop unused se_lun->lun_acl_list · 84786546
      Nicholas Bellinger authored
      Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Sagi Grimberg <sagig@mellanox.com>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      84786546
    • Nicholas Bellinger's avatar
      target: Convert core_tpg_deregister to use list splice · 22793de5
      Nicholas Bellinger authored
      This patch converts core_tpg_deregister() to perform a list splice
      for any remaining dynamically generated se_node_acls attached to
      se_tpg, before calling kfree(nacl) to free memory.
      Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Sagi Grimberg <sagig@mellanox.com>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      22793de5
    • Nicholas Bellinger's avatar
      target: Convert se_tpg->acl_node_lock to ->acl_node_mutex · 403edd78
      Nicholas Bellinger authored
      This patch converts se_tpg->acl_node_lock to struct mutex, so that
      ->acl_node_acl walkers in core_clear_lun_from_tpg() can block when
      calling core_disable_device_list_for_node().
      
      It also updates core_dev_add_lun() to hold ->acl_node_mutex when
      calling core_tpg_add_node_to_devs() to build ->lun_entry_hlist
      for dynamically generated se_node_acl.
      Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Sagi Grimberg <sagig@mellanox.com>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      403edd78
    • Nicholas Bellinger's avatar
      target: Convert se_portal_group->tpg_lun_list[] to RCU hlist · 6bb82612
      Nicholas Bellinger authored
      This patch converts the fixed size se_portal_group->tpg_lun_list[]
      to use modern RCU with hlist_head in order to support an arbitary
      number of se_lun ports per target endpoint.
      
      It includes dropping core_tpg_alloc_lun() from core_dev_add_lun(),
      and calling it directly from target_fabric_make_lun() to allocate
      a new se_lun.  And add a new target_fabric_port_release() configfs
      item callback to invoke kfree_rcu() to release memory during
      se_lun->lun_group shutdown.
      
      Also now that se_node_acl->lun_entry_hlist is using RCU, convert
      existing tpg_lun_lock to struct mutex so core_tpg_add_node_to_devs()
      can perform RCU updater logic without releasing ->tpg_lun_mutex.
      
      Also, drop core_tpg_clear_object_luns() and it's single consumer
      in iscsi-target, which is duplicating TPG LUN shutdown logic and
      is current code results in a NOP.
      
      Finally, sbp-target and xen-scsiback fabric driver conversions are
      included, which are required due to the non-standard way they use
      ->tpg_lun_hlist.
      Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Sagi Grimberg <sagig@mellanox.com>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Cc: Chris Boot <bootc@bootc.net>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      6bb82612
    • Christoph Hellwig's avatar
      target/pr: cleanup core_scsi3_pr_seq_non_holder · 9fcb57f3
      Christoph Hellwig authored
      Clean up the mess of registered variables, and pass the isid mismatch
      flag explicitly instead of overloading the registration type.
      Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
      Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      9fcb57f3
    • Nicholas Bellinger's avatar
      target/pr: Change alloc_registration to avoid pr_reg_tg_pt_lun · 79dc9c9e
      Nicholas Bellinger authored
      This patch changes __core_scsi3_do_alloc_registration() code to
      drop pr_reg->pr_reg_tg_pt_lun pointer usage in favor of a new
      pr_reg RPTI + existing pr_reg->pr_aptpl_target_lun used by
      APTPL metadata logic.
      
      It also includes changes to REGISTER, REGISTER_AND_MOVE and APTPL
      feature bit codepaths to use rcu_dereference_check() with the
      expected non-zero se_dev_entry->pr_kref reference held.
      Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Sagi Grimberg <sagig@mellanox.com>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      79dc9c9e
    • Nicholas Bellinger's avatar
      target/pr: Use atomic bitop for se_dev_entry->deve_flags reservation check · 80bfdfa9
      Nicholas Bellinger authored
      This patch converts the core_scsi3_pr_seq_non_holder() check for non
      reservation holding registrations to use an atomic bitop in ->deve_flags
      to determine if a registration is currently active.
      
      It also includes associated a set_bit() in __core_scsi3_add_registration()
      and clear_bit() in __core_scsi3_free_registration(), if se_dev_entry still
      exists, and has not already been released via se_dev_entry shutdown path
      in core_disable_device_list_for_node().
      
      Also, clear_bit in core_disable_device_list_for_node as well to ensure
      the read-critical path in core_scsi3_pr_seq_non_holder() picks up the
      new state, preceeding the final kfree_rcu() call.
      Reported-by: default avatarChristoph Hellwig <hch@lst.de>
      Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
      Cc: Sagi Grimberg <sagig@mellanox.com>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      80bfdfa9
    • Nicholas Bellinger's avatar
      target: Convert se_node_acl->device_list[] to RCU hlist · 29a05dee
      Nicholas Bellinger authored
      This patch converts se_node_acl->device_list[] table for mappedluns
      to modern RCU hlist_head usage in order to support an arbitrary number
      of node_acl lun mappings.
      
      It converts transport_lookup_*_lun() fast-path code to use RCU read path
      primitives when looking up se_dev_entry.  It adds a new hlist_head at
      se_node_acl->lun_entry_hlist for this purpose.
      
      For transport_lookup_cmd_lun() code, it works with existing per-cpu
      se_lun->lun_ref when associating se_cmd with se_lun + se_device.
      Also, go ahead and update core_create_device_list_for_node() +
      core_free_device_list_for_node() to use ->lun_entry_hlist.
      
      It also converts se_dev_entry->pr_ref_count access to use modern
      struct kref counting, and updates core_disable_device_list_for_node()
      to kref_put() and block on se_deve->pr_comp waiting for outstanding PR
      special-case PR references to drop, then invoke kfree_rcu() to wait
      for the RCU grace period to complete before releasing memory.
      
      So now that se_node_acl->lun_entry_hlist fast path access uses RCU
      protected pointers, go ahead and convert remaining non-fast path
      RCU updater code using ->lun_entry_lock to struct mutex to allow
      callers to block while walking se_node_acl->lun_entry_hlist.
      
      Finally drop the left-over core_clear_initiator_node_from_tpg() that
      originally cleared lun_access during se_node_acl shutdown, as post
      RCU conversion it now becomes duplicated logic.
      Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
      Cc: Christoph Hellwig <hch@lst.de>
      Cc: Sagi Grimberg <sagig@mellanox.com>
      Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
      Signed-off-by: default avatarNicholas Bellinger <nab@linux-iscsi.org>
      29a05dee
  2. 31 May, 2015 31 commits