linux/drivers/target
Nicholas Bellinger aafc9d158b iscsi-target: Fix iscsit_free_cmd() se_cmd->cmd_kref shutdown handling
With the introduction of target_get_sess_cmd() referencing counting for
ISCSI_OP_SCSI_CMD processing with iser-target, iscsit_free_cmd() usage
in traditional iscsi-target driver code now needs to be aware of the
active I/O shutdown case when a remaining se_cmd->cmd_kref reference may
exist after transport_generic_free_cmd() completes, requiring a final
target_put_sess_cmd() to release iscsi_cmd descriptor memory.

This patch changes iscsit_free_cmd() to invoke __iscsit_free_cmd() before
transport_generic_free_cmd() -> target_put_sess_cmd(), and also avoids
aquiring the per-connection queue locks for typical fast-path calls
during normal ISTATE_REMOVE operation.

Also update iscsit_free_cmd() usage throughout iscsi-target to
use the new 'bool shutdown' parameter.

This patch fixes a regression bug introduced during v3.10-rc1 in
commit 3e1c81a95, that was causing the following WARNING to appear:

[  257.235153] ------------[ cut here]------------
[  257.240314] WARNING: at kernel/softirq.c:160 local_bh_enable_ip+0x3c/0x86()
[  257.248089] Modules linked in: vhost_scsi ib_srpt ib_cm ib_sa ib_mad ib_core tcm_qla2xxx tcm_loop
	tcm_fc libfc iscsi_target_mod target_core_pscsi target_core_file
	target_core_iblock target_core_mod configfs ipv6 iscsi_tcp libiscsi_tcp
	libiscsi scsi_transport_iscsi loop acpi_cpufreq freq_table mperf
	kvm_intel kvm crc32c_intel button ehci_pci pcspkr joydev i2c_i801
	microcode ext3 jbd raid10 raid456 async_pq async_xor xor async_memcpy
	async_raid6_recov raid6_pq async_tx raid1 raid0 linear igb hwmon
	i2c_algo_bit i2c_core ptp ata_piix libata qla2xxx uhci_hcd ehci_hcd
	mlx4_core scsi_transport_fc scsi_tgt pps_core
[  257.308748] CPU: 1 PID: 3295 Comm: iscsi_ttx Not tainted 3.10.0-rc2+ #103
[  257.316329] Hardware name: Intel Corporation S5520HC/S5520HC, BIOS S5500.86B.01.00.0057.031020111721 03/10/2011
[  257.327597]  ffffffff814c24b7 ffff880458331b58 ffffffff8138eef2 ffff880458331b98
[  257.335892]  ffffffff8102c052 ffff880400000008 0000000000000000 ffff88085bdf0000
[  257.344191]  ffff88085bdf00d8 ffff88085bdf00e0 ffff88085bdf00f8 ffff880458331ba8
[  257.352488] Call Trace:
[  257.355223]  [<ffffffff8138eef2>] dump_stack+0x19/0x1f
[  257.360963]  [<ffffffff8102c052>] warn_slowpath_common+0x62/0x7b
[  257.367669]  [<ffffffff8102c080>] warn_slowpath_null+0x15/0x17
[  257.374181]  [<ffffffff81032345>] local_bh_enable_ip+0x3c/0x86
[  257.380697]  [<ffffffff813917fd>] _raw_spin_unlock_bh+0x10/0x12
[  257.387311]  [<ffffffffa029069c>] iscsit_free_r2ts_from_list+0x5e/0x67 [iscsi_target_mod]
[  257.396438]  [<ffffffffa02906c5>] iscsit_release_cmd+0x20/0x223 [iscsi_target_mod]
[  257.404893]  [<ffffffffa02977a4>] lio_release_cmd+0x3a/0x3e [iscsi_target_mod]
[  257.412964]  [<ffffffffa01d59a1>] target_release_cmd_kref+0x7a/0x7c [target_core_mod]
[  257.421712]  [<ffffffffa01d69bc>] target_put_sess_cmd+0x5f/0x7f [target_core_mod]
[  257.430071]  [<ffffffffa01d6d6d>] transport_release_cmd+0x59/0x6f [target_core_mod]
[  257.438625]  [<ffffffffa01d6eb4>] transport_put_cmd+0x131/0x140 [target_core_mod]
[  257.446985]  [<ffffffffa01d6192>] ? transport_wait_for_tasks+0xfa/0x1d5 [target_core_mod]
[  257.456121]  [<ffffffffa01d6f11>] transport_generic_free_cmd+0x4e/0x52 [target_core_mod]
[  257.465159]  [<ffffffff81050537>] ? __migrate_task+0x110/0x110
[  257.471674]  [<ffffffffa02904ba>] iscsit_free_cmd+0x46/0x55 [iscsi_target_mod]
[  257.479741]  [<ffffffffa0291edb>] iscsit_immediate_queue+0x301/0x353 [iscsi_target_mod]
[  257.488683]  [<ffffffffa0292f7e>] iscsi_target_tx_thread+0x1c6/0x2a8 [iscsi_target_mod]
[  257.497623]  [<ffffffff81047486>] ? wake_up_bit+0x25/0x25
[  257.503652]  [<ffffffffa0292db8>] ? iscsit_ack_from_expstatsn+0xd5/0xd5 [iscsi_target_mod]
[  257.512882]  [<ffffffff81046f89>] kthread+0xb0/0xb8
[  257.518329]  [<ffffffff81046ed9>] ? kthread_freezable_should_stop+0x60/0x60
[  257.526105]  [<ffffffff81396fec>] ret_from_fork+0x7c/0xb0
[  257.532133]  [<ffffffff81046ed9>] ? kthread_freezable_should_stop+0x60/0x60
[  257.539906] ---[ end trace 5520397d0f2e0800 ]---

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-05-31 01:21:28 -07:00
..
iscsi iscsi-target: Fix iscsit_free_cmd() se_cmd->cmd_kref shutdown handling 2013-05-31 01:21:28 -07:00
loopback tcm: switch to ->show_info() 2013-04-09 14:13:19 -04:00
sbp Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2013-03-02 11:43:27 -08:00
tcm_fc tcm_fc: Check for aborted sequence 2013-04-25 01:05:28 -07:00
Kconfig
Makefile
target_core_alua.c target: Fix incorrect fallthrough of ALUA Standby/Offline/Transition CDBs 2013-04-11 01:48:49 -07:00
target_core_alua.h
target_core_configfs.c target: Have dev/enable show if TCM device is configured 2013-05-03 16:46:02 -07:00
target_core_device.c target: Remove unused struct members in se_dev_entry 2013-05-03 16:42:18 -07:00
target_core_fabric_configfs.c target: Add missing mapped_lun bounds checking during make_mappedlun setup 2013-02-18 18:47:28 -08:00
target_core_fabric_lib.c
target_core_file.c target/file: Fix off-by-one READ_CAPACITY bug for !S_ISBLK export 2013-05-30 17:46:27 -07:00
target_core_file.h target/file: Bump FD_MAX_SECTORS to 2048 to handle 1M sized I/Os 2013-03-19 17:24:28 -07:00
target_core_hba.c
target_core_iblock.c target/iblock: Fix WCE=1 + DPOFUA=1 backend WRITE regression 2013-05-15 01:46:34 -07:00
target_core_iblock.h
target_core_internal.h target: Remove unused struct members in se_dev_entry 2013-05-03 16:42:18 -07:00
target_core_pr.c target: writev() on single-element vector is pointless 2013-02-26 02:46:11 -05:00
target_core_pr.h
target_core_pscsi.c target/pscsi: Reject cross page boundary case in pscsi_map_sg 2013-03-19 17:31:14 -07:00
target_core_pscsi.h
target_core_rd.c target/rd: Add ramdisk bit for NULLIO operation 2013-05-11 16:22:39 -07:00
target_core_rd.h target/rd: Add ramdisk bit for NULLIO operation 2013-05-11 16:22:39 -07:00
target_core_sbc.c target: Add sbc_execute_unmap() helper 2013-04-25 01:05:24 -07:00
target_core_spc.c target: Fix parameter list length checking in MODE SELECT 2013-02-13 12:16:11 -08:00
target_core_stat.c
target_core_tmr.c target: Remove useless if statement 2013-02-13 11:27:22 -08:00
target_core_tpg.c target: fix possible memory leak in core_tpg_register() 2013-03-18 12:45:52 -07:00
target_core_transport.c target: Propigate up ->cmd_kref put return via transport_generic_free_cmd 2013-05-31 01:21:23 -07:00
target_core_ua.c
target_core_ua.h