improve the approach to get iscsi_tcp_host and add more iscsi session…

… info

Orabug: 37362180
Signed-off-by: Richard Li <[email protected]>

drgn_tools/iscsi.py

@@ -0,0 +1,213 @@
+# Copyright (c) 2024, Oracle and/or its affiliates.
+# Licensed under the Universal Permissive License v 1.0 as shown at https://oss.oracle.com/licenses/upl/
+"""
+Helper for iscsi
+"""
+import argparse
+from typing import Iterator
+from typing import Tuple
+
+from drgn import container_of
+from drgn import Object
+from drgn import Program
+from drgn import sizeof
+from drgn.helpers.common import escape_ascii_string
+from drgn.helpers.common.type import enum_type_to_class
+from drgn.helpers.linux.list import list_for_each_entry
+
+from drgn_tools.corelens import CorelensModule
+from drgn_tools.scsi import for_each_scsi_host
+from drgn_tools.scsi import host_module_name
+from drgn_tools.table import print_dictionary
+from drgn_tools.table import print_table
+from drgn_tools.util import enum_name_get
+from drgn_tools.util import has_member
+
+ISCSI_SESSION_STATES = ["LOGGED_IN", "FAILED", "FREE"]
+
+
+def for_each_iscsi_tcp_host(prog: Program) -> Iterator[Object]:
+    """
+    Iterates through all scsi host devices and returns a
+    iterator of hosts of iscsi_tcp type
+    :returns: a iterator of ``struct Scsi_Host *``
+    """
+    for shost in for_each_scsi_host(prog):
+        if host_module_name(shost) == "iscsi_tcp":
+            yield shost
+
+
+def __get_iscsi_sw_tcp_host(prog: Program, iscsi_tcp_host: Object) -> Object:
+    """
+    Get the iscsi_sw_tcp_host asscociated with an iscsi tcp host
+    :returns: ``struct iscsi_sw_tcp_host``
+    """
+    return Object(
+        prog,
+        "struct iscsi_sw_tcp_host",
+        address=iscsi_tcp_host.hostdata.address_of_().value_()
+        + sizeof(prog.type("struct iscsi_host")),
+    )
+
+
+def shost_for_each_device(prog: Program, shost: Object) -> Iterator[Object]:
+    """
+    Get a list of scsi_devices asscociated with an Scsi_Host
+    :returns: a iterator of ``struct scsi_device``
+    """
+    return list_for_each_entry(
+        "struct scsi_device", shost.__devices.address_of_(), "siblings"
+    )
+
+
+def get_dev_name(prog: Program, sdev: Object) -> str:
+    """
+    Get the device name associated with scsi_device.
+    :return ``str``
+    """
+    rq = sdev.request_queue
+    dev = container_of(rq.kobj.parent, "struct device", "kobj")
+    return dev.kobj.name.string_().decode()
+
+
+def for_each_iscsi_session(prog: Program) -> Iterator[Object]:
+    """
+    Iterates through all iscsi tcp hosts, gets their associated iscsi_sw_tcp_hosts and return a
+    iterator of their sessions.
+    :returns: a iterator of ``struct iscsi_session *``
+
+    """
+    for h in for_each_iscsi_tcp_host(prog):
+        yield __get_iscsi_sw_tcp_host(prog, h).session
+
+
+def print_iscsi_table(prog: Program) -> None:
+    """
+    Prints basic iscsi information
+    """
+    output = [
+        [
+            "SCSI_HOST",
+            "NAME",
+            "DRIVER",
+            "Busy",
+            "Blocked",
+            "Fail",
+            "State",
+            "ISCSI_SESSION",
+        ]
+    ]
+    for shost in for_each_iscsi_tcp_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 has_member(shost, "host_busy"):
+            host_busy = shost.host_busy.counter.value_()
+        else:
+            host_busy = "n/a"
+        output.append(
+            [
+                hex(shost.value_()),
+                f"host{shost.host_no.value_()}",
+                host_module_name(shost),
+                host_busy,
+                shost.host_blocked.counter.value_(),
+                shost.host_failed.value_(),
+                shost.shost_state.format_(type_name=False),
+                hex(__get_iscsi_sw_tcp_host(prog, shost).session.value_()),
+            ]
+        )
+    print_table(output)
+
+
+def for_each_attached_device(
+    prog: Program, shost: Object
+) -> Iterator[Tuple[Object, str]]:
+    for scsi_dev in shost_for_each_device(prog, shost):
+        name = get_dev_name(prog, scsi_dev)
+        yield scsi_dev, name
+
+
+def print_iscsi_report(prog: Program) -> None:
+    """
+    Prints a comprehensive report including iscsi table and session stats. More info can be added later if needed.
+    """
+    print_iscsi_table(prog)
+    print()
+    output = {}
+
+    for session in for_each_iscsi_session(prog):
+        print("**********")
+        conn = session.leadconn
+
+        persistent_address = escape_ascii_string(
+            conn.persistent_address.string_()
+        )
+        persistent_port = int(conn.persistent_port)
+        output["Session"] = hex(session.value_())
+        output["SID"] = str(int(session.cls_session.sid))
+        output["Persistent Portal"] = f"{persistent_address}:{persistent_port}"
+        output["Iface Name"] = escape_ascii_string(session.ifacename.string_())
+        output["Session State"] = ISCSI_SESSION_STATES[
+            session.cls_session.state
+        ]
+        connstate = enum_type_to_class(
+            prog.type("enum iscsi_connection_state"), "connstate"
+        )
+        output["Connection State"] = str(
+            enum_name_get(
+                connstate,
+                conn.cls_conn.state,
+                "UNKNOWN",
+            )
+        )
+        output["Initiatorname"] = escape_ascii_string(
+            session.initiatorname.string_()
+        )
+        output["Targetname"] = escape_ascii_string(
+            session.targetname.string_()
+        )
+
+        print_dictionary(output)
+
+        print("Attached SCSI devices: ")
+        print("**********")
+        print(
+            "Host Number: {}  STATE: {}".format(
+                session.host.host_no.value_(),
+                session.host.shost_state.format_(type_name=False),
+            )
+        )
+
+        for scsi_dev, name in for_each_attached_device(prog, session.host):
+            print(
+                "scsi{} Channel {} Id {} Lun: {}".format(
+                    session.host.host_no.value_(),
+                    int(scsi_dev.channel),
+                    int(scsi_dev.id),
+                    int(scsi_dev.lun),
+                )
+            )
+            sdev_state = enum_type_to_class(
+                prog.type("enum scsi_device_state"), "sdev_state"
+            )
+            state = enum_name_get(
+                sdev_state,
+                scsi_dev.sdev_state,
+                "UNKNOWN",
+            )
+            print("  Attached iscsi disk: {}  State: {}".format(name, state))
+
+        print()
+
+
+class IscsiDump(CorelensModule):
+    """
+    Dump iscsi info
+    """
+
+    name = "iscsi"
+
+    def run(self, prog: Program, args: argparse.Namespace) -> None:
+        print_iscsi_report(prog)

tests/test_iscsi.py

@@ -0,0 +1,7 @@
+# Copyright (c) 2024, Oracle and/or its affiliates.
+# Licensed under the Universal Permissive License v 1.0 as shown at https://oss.oracle.com/licenses/upl/
+from drgn_tools import iscsi
+
+
+def test_iscsi(prog):
+    iscsi.print_iscsi_report(prog)