forked from pool/s390-tools
137 lines
6.1 KiB
Diff
137 lines
6.1 KiB
Diff
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Subject: lstape, lsluns: handle non-zfcp; lin_tape multiple paths
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From: Steffen Maier <maier@linux.ibm.com>
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Description: lstape, lsluns: handle non-zfcp; lin_tape multiple paths
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Symptom: lstape shows unexpected additional Device suffix numbers in
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excess output columns for each additional path of the same
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tape/changer driven by the IBM lin_tape device driver
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(independent of actual path failover enablement in lin_tape).
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It also shows a wrong number of found devices in the header
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(without --scsi-only).
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lstape prints error about "Unexpected extra argument:" and the
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usage for "sg_inq" along with wrong tabular output.
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lsluns prints ENOENT error text for "cat" on SCSI device sysfs
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attributes hba_id, wwpn, and fcp_lun.
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lstape with --verbose option prints ENOENT error text for
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"cat" on SCSI device sysfs attributes hba_id and wwpn.
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lstape man page: Description of --type and <devbusid> filter
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for channel tapes is incomplete. SCSI output description is
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incomplete.
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lstape shows "N/A" instead of the HBA device bus-ID with
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virtio-scsi-ccw.
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Problem: s390-tools-1.8.0 before the first upstream commit b627b8d8e1ab
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("Initial s390-tools-2.0.0 import") introduced SCSI
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tape/changer output for lstape. It used the SCSI device serial
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number as lookup key to find a match in IBM lin_tape device
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driver proc-fs output for a given SCSI device name. Multiple
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paths to the same tape/changer have the same serial number.
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Multiple matches cause excess arguments to printf. Explaining
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the resulting output, the bash man page says: "The format is
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reused as necessary to consume all of the arguments." This
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also causes a wrong number of found devices.
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The default bash settings have nullglob disabled so if
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$SCSI_DEV/scsi_generic* aka
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/sys/bus/scsi/devices/*:*:*:*/scsi_generic* does not match
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anything, it leaves the glob pattern unmodified and
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SG_DEV=$(basename $SG_DEV/*) results in the literal "*". If
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$SG_INQ exists, it invoked sg_inq with more than the one
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allowed positional argument for a SCSI generic device node
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"sg_inq /dev/*". Causing error messages and the usage of
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sg_inq to land in $TAPE_SERIAL.
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lsluns iterates SCSI generic devices and unconditionally
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reads zfcp-specific SCSI device sysfs attributes hba_id, wwpn,
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and fcp_lun.
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lstape --verbose unconditionally reads zfcp-specific SCSI
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device sysfs attributes hba_id and wwpn.
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<devbusid> filter missing from synopsis. <device-type> example
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at wrong place with <devbusid> filter. <devbusid> filter
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option description is a duplicate of <device-type> filter
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option description. SCSI output description misses fields.
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Lstape only used the zfcp-specific sysfs attribute hba_id.
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Solution: Prefer sysfs to find lin_tape device name for SCSI device.
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Fallback: The lin_tape proc-fs output format has changed over
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the years. The HBA device driver string can contain whitespace
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(e.g. "Virtio SCSI HBA") and breaks the field numbers with
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tokenized parsing. Grep for the SCSI device name as word (to
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skip names with same substring, such as 0:0:1:1 also matching
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0:0:1:10) and cut the first field 'Number' (lin_tape device
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name suffix). If there is no SCSI column at all [lin_tape
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before v2.2.0] (and no SCSI LLDD or other column with a name
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accidentally matching an existing SCSI device name), we get no
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match and better bail out with the initialized "N/A" for the
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lstape column "Device".
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To not have to rely on the nullglob setting, explicitly check
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for the existence of $SCSI_DEV/scsi_generic before evaluating
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SG_DEV=$(basename $SG_DEV/*). Also handle availability of
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sg_inq but absence of scsi_generic individually to provide the
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user with a hint if only sg is missing.
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Simply skip non-zfcp SCSI devices, such as iSCSI or
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virtio-scsi-ccw, to not erroneously access absent attributes.
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Assume "N/A" for HBA and WWPN of non-zfcp SCSI devices, such
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as iSCSI or virtio-scsi-ccw, to not erroneously access absent
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zfcp-specific sysfs attributes.
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Add <devbusid> filter to synopsis. Move <device-type> example
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to <device-type> option. Replace <devbusid> filter option
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description. Move existing SCSI output description to a new
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subsection and add description of missing fields.
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Also search sysfs for an ancestor with subsystem ccw.
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Reproduction: Attach more than one path to the same SCSI tape or changer and
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load the IBM lin_tape device driver.
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Unload sg kernel module.
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Attach non-zfcp SCSI devices such as iSCSI or virtio-scsi-ccw.
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Attach non-zfcp SCSI devices such as iSCSI or virtio-scsi-ccw.
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man lstape
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Attach SCSI tape or changer with virtio-scsi-ccw to a KVM
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guest and run "lstape --verbose".
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Upstream-ID: -
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Problem-ID: 170633
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Signed-off-by: Steffen Maier <maier@linux.ibm.com>
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---
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zconf/lstape | 8 ++++++--
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1 file changed, 6 insertions(+), 2 deletions(-)
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--- a/zconf/lstape
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+++ b/zconf/lstape
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@@ -335,9 +335,13 @@ function SysfsCreateListSCSI()
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$STATE
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if $VERBOSE; then
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+ HBA_ID="N/A"
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+ [ -r $SCSI_DEV/hba_id ] && HBA_ID=$(cat $SCSI_DEV/hba_id)
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+ WWPN="N/A"
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+ [ -r $SCSI_DEV/wwpn ] && WWPN=$(cat $SCSI_DEV/wwpn)
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printf "$SCSIVFORMAT" \
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- $(cat $SCSI_DEV/hba_id) \
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- $(cat $SCSI_DEV/wwpn) \
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+ "$HBA_ID" \
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+ "$WWPN" \
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$TAPE_SERIAL
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fi
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done
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