Update scsi host and added scsi devices with scsiinfo module

Signed-off-by: Rajan Shanmugavelu <[email protected]

Author: vashanmu

drgn_tools/iscsi.py

@@ -121,7 +121,7 @@ def print_iscsi_sessions(prog: Program) -> None:
             )
         )
 
-        for scsi_dev in for_each_scsi_host_device(prog, session.host):
+        for scsi_dev in for_each_scsi_host_device(prog):
             name = scsi_device_name(prog, scsi_dev)
             print(
                 "scsi{} Channel {} Id {} Lun: {}".format(

drgn_tools/scsi.py

@@ -1,24 +1,35 @@
-# Copyright (c) 2023, Oracle and/or its affiliates.
+# Copyright (c) 2025, Oracle and/or its affiliates.
 # Licensed under the Universal Permissive License v 1.0 as shown at https://oss.oracle.com/licenses/upl/
 """
-Helper to print scsi hosts
+ Helper to print IO substem useful information from the vmcore or
+ live system.
 """
 import argparse
 from typing import Iterator
 
-import drgn
+from drgn import cast
 from drgn import container_of
 from drgn import FaultError
 from drgn import Object
 from drgn import Program
+from drgn.helpers.linux.block import _class_to_subsys
+from drgn.helpers.linux.block import for_each_disk
 from drgn.helpers.linux.list import list_for_each_entry
 
 from drgn_tools.corelens import CorelensModule
-from drgn_tools.device import class_to_subsys
+from drgn_tools.module import ensure_debuginfo
 from drgn_tools.table import print_table
 from drgn_tools.util import has_member
 
 
+"""
+ Dictionary of gendisks being used as hashmap with request_queue address as the key,
+ this is need to lookup the disk names for UEK6 or older kernel where gendisk is not
+ part of the request_queue structure.
+"""
+gendisk_map = {}
+
+
 def for_each_scsi_host(prog: Program) -> Iterator[Object]:
     """
     Iterate through all scsi hosts and returns an
@@ -29,7 +40,7 @@ def for_each_scsi_host(prog: Program) -> Iterator[Object]:
         "knode_class"
     )
 
-    subsys_p = class_to_subsys(prog["shost_class"].address_of_())
+    subsys_p = _class_to_subsys(prog["shost_class"].address_of_())
     devices = subsys_p.klist_devices.k_list.address_of_()
 
     if class_in_private:
@@ -52,21 +63,20 @@ def host_module_name(shost: Object) -> str:
     """
     try:
         name = shost.hostt.module.name.string_().decode()
-    except drgn.FaultError:
+    except FaultError:
         name = "unknown"
     return name
 
 
-def for_each_scsi_host_device(
-    prog: Program, shost: Object
-) -> Iterator[Object]:
+def for_each_scsi_host_device(shost: Object) -> Iterator[Object]:
     """
-    Get a list of scsi_device associated with a Scsi_Host.
-    :returns: an iterator of ``struct scsi_device *``
+    Iterates thru all scsi device and returns a scsi_device address
     """
-    return list_for_each_entry(
-        "struct scsi_device", shost.__devices.address_of_(), "siblings"
-    )
+    for scsi_dev in list_for_each_entry(
+            "struct scsi_device",
+            shost.__devices.address_of_(),
+            "siblings"):
+        yield scsi_dev
 
 
 def scsi_device_name(prog: Program, sdev: Object) -> str:
@@ -82,42 +92,212 @@ def scsi_device_name(prog: Program, sdev: Object) -> str:
         return ""
 
 
+def load_gendisk(prog: Program) -> None:
+    """
+    This method loads the all the gendisk into the global hashmap.
+    """
+    msg = ensure_debuginfo(prog, ["sd_mod"])
+    if msg:
+        print(msg)
+        return
+
+    for disk in for_each_disk(prog):
+        disk_rq = hex(disk.queue)
+        gendisk_map[disk_rq] = disk
+    return
+
+
+def scsi_id(scsi_dev: Object) -> str:
+    """
+    Return Host:Controller:Target:Lun as a string.
+    """
+    if not scsi_dev:
+        return "<unknown>"
+    hctl = "[" + str(scsi_dev.host.host_no.value_()) + ":" + \
+        str(scsi_dev.channel.value_()) + ":" + \
+        str(scsi_dev.id.value_()) + ":" + \
+        str(scsi_dev.lun.value_()) + "]"
+    return hctl
+
+
 def print_scsi_hosts(prog: Program) -> None:
     """
     Prints scsi host information
     """
     output = [
-        ["SCSI_HOST", "NAME", "DRIVER", "Busy", "Blocked", "Fail", "State"]
+        [
+            "SCSI_HOST",
+            "NAME",
+            "DRIVER",
+            "Version",
+            "Busy",
+            "Blocked",
+            "Fail",
+            "State",
+            "EH val",
+        ]
     ]
+
     for shost in for_each_scsi_host(prog):
         """
         Since 6eb045e092ef ("scsi: core: avoid host-wide host_busy counter for scsi_mq"),
         host_busy is no longer a member of struct Scsi_Host.
         """
+        if host_module_name(shost) == "ahci":
+            continue
+
+        if shost.hostt.module.version:
+            modver = shost.hostt.module.version.string_().decode()
+        else:
+            modver = "n/a"
+
         if has_member(shost, "host_busy"):
             host_busy = shost.host_busy.counter.value_()
         else:
             host_busy = "n/a"
+
+        if has_member(shost, "eh_deadline"):
+            eh_deadline = shost.eh_deadline.value_()
+        else:
+            eh_deadline = "n/a"
+
         output.append(
             [
                 hex(shost.value_()),
                 f"host{shost.host_no.value_()}",
                 host_module_name(shost),
+                modver,
                 host_busy,
                 shost.host_blocked.counter.value_(),
                 shost.host_failed.value_(),
                 shost.shost_state.format_(type_name=False),
+                eh_deadline,
             ]
         )
     print_table(output)
 
 
+def print_shost_header(shost: Object) -> None:
+    """
+    print scsi host header.
+    """
+    print(
+        "--------------------------------------------------"
+        "-------------------------------------------------"
+    )
+    output = [
+        [
+            "HOST",
+            "DRIVER",
+            "Scsi_Host",
+            "shost_data",
+            "hostdata",
+        ]
+    ]
+
+    shostdata = hex(shost.shost_data.address_of_().value_())
+    hostdata = hex(shost.hostdata.address_of_().value_())
+    output.append(
+        [
+            shost.shost_gendev.kobj.name.string_().decode(),
+            host_module_name(shost),
+            hex(shost),
+            shostdata,
+            hostdata,
+        ]
+    )
+    print_table(output)
+    print(
+        "--------------------------------------------------"
+        "-------------------------------------------------"
+    )
+    return
+
+
+def print_shost_devs(prog: Program) -> None:
+    """
+    print all scsi devices for a Scsi_Host
+    """
+    msg = ensure_debuginfo(prog, ["sd_mod"])
+    if msg:
+        print(msg)
+        return
+
+    for shost in for_each_scsi_host(prog):
+        if host_module_name(shost) == "ahci":
+            continue
+        print_shost_header(shost)
+        output = [
+            [
+                "Device",
+                "H:C:T:L",
+                "Scsi Device Addr",
+                "Vendor",
+                "State",
+                "IO Req",
+                "IO Done",
+                "IO Error",
+            ]
+        ]
+
+        for scsi_dev in for_each_scsi_host_device(shost):
+            if prog.type("struct request_queue").has_member("disk"):
+                gendisk = cast("struct gendisk *", scsi_dev.request_queue.disk)
+                if not gendisk:
+                    continue
+                diskname = gendisk.disk_name.address_of_().string_().decode()
+            else:
+                diskname = gendisk_map[hex(scsi_dev.request_queue)].disk_name.string_().decode()
+
+            vendor = scsi_dev.vendor.string_().decode()
+            devstate = str(scsi_dev.sdev_state.format_(type_name=False))
+
+            output.append(
+                [
+                    str(diskname),
+                    scsi_id(scsi_dev),
+                    hex(scsi_dev),
+                    str(vendor),
+                    devstate,
+                    scsi_dev.iorequest_cnt.counter.value_(),
+                    scsi_dev.iodone_cnt.counter.value_(),
+                    scsi_dev.ioerr_cnt.counter.value_(),
+                ]
+            )
+        print_table(output)
+
+
 class ScsiInfo(CorelensModule):
     """
     Corelens Module for scsi device information
     """
 
     name = "scsiinfo"
 
+    debuginfo_kmods = ["sd_mod"]
+
+    default_args = [
+        [
+            "--hosts",
+            "--devices",
+        ]
+    ]
+
+    def add_args(self, parser: argparse.ArgumentParser) -> None:
+        parser.add_argument(
+            "--hosts",
+            action="store_true",
+            help="Print Scsi Hosts",
+        )
+        parser.add_argument(
+            "--devices",
+            action="store_true",
+            help="Print Scsi Devices",
+        )
+
     def run(self, prog: Program, args: argparse.Namespace) -> None:
-        print_scsi_hosts(prog)
+        if args.hosts:
+            print_scsi_hosts(prog)
+        if args.devices:
+            load_gendisk(prog)
+            print_shost_devs(prog)