xref: /OK3568_Linux_fs/kernel/Documentation/scsi/tcm_qla2xxx.rst (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun.. SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun
3*4882a593Smuzhiyun========================
4*4882a593Smuzhiyuntcm_qla2xxx Driver Notes
5*4882a593Smuzhiyun========================
6*4882a593Smuzhiyun
7*4882a593Smuzhiyuntcm_qla2xxx jam_host attribute
8*4882a593Smuzhiyun------------------------------
9*4882a593SmuzhiyunThere is now a new module endpoint atribute called jam_host
10*4882a593Smuzhiyunattribute::
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun	jam_host: boolean=0/1
13*4882a593Smuzhiyun
14*4882a593SmuzhiyunThis attribute and accompanying code is only included if the
15*4882a593SmuzhiyunKconfig parameter TCM_QLA2XXX_DEBUG is set to Y
16*4882a593Smuzhiyun
17*4882a593SmuzhiyunBy default this jammer code and functionality is disabled
18*4882a593Smuzhiyun
19*4882a593SmuzhiyunUse this attribute to control the discarding of SCSI commands to a
20*4882a593Smuzhiyunselected host.
21*4882a593Smuzhiyun
22*4882a593SmuzhiyunThis may be useful for testing error handling and simulating slow drain
23*4882a593Smuzhiyunand other fabric issues.
24*4882a593Smuzhiyun
25*4882a593SmuzhiyunSetting a boolean of 1 for the jam_host attribute for a particular host
26*4882a593Smuzhiyunwill discard the commands for that host.
27*4882a593Smuzhiyun
28*4882a593SmuzhiyunReset back to 0 to stop the jamming.
29*4882a593Smuzhiyun
30*4882a593SmuzhiyunEnable host 4 to be jammed::
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun  echo 1 > /sys/kernel/config/target/qla2xxx/21:00:00:24:ff:27:8f:ae/tpgt_1/attrib/jam_host
33*4882a593Smuzhiyun
34*4882a593SmuzhiyunDisable jamming on host 4::
35*4882a593Smuzhiyun
36*4882a593Smuzhiyun  echo 0 > /sys/kernel/config/target/qla2xxx/21:00:00:24:ff:27:8f:ae/tpgt_1/attrib/jam_host
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