It should be sufficient to hold the lock just for removing the session
from the session list. Everything else should be covered by the session
specific lock.
On top of that, at present we can get a deadlock caused by waiting on
the CAM SIM reference count while holding the global lock. A specific
scenario involving ZFS is this:
- concurrent termination of two sessions, S1 and S2
- session S1 completed all I/Os and sleeps in CAM waiting for device
close by ZFS;
- session S2 is also dead now, but can not forcefully complete
outstanding requests by calling iscsi_session_cleanup() from
iscsi_maintenance_thread_terminate(), since it can't get the same
global sc_lock;
- as soon as there are unfinished requests, ZFS can not do
spa_config_enter() as writer, and so can not close the device for
session S1;
- deadlock.
Reported by: Ben RUBSON <ben.rubson@gmail.com>
Tested by: Ben RUBSON <ben.rubson@gmail.com>
Reviewed by: mav, trasz
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D12652
Decouple the send and receive limits on the amount of data in a single
iSCSI PDU. MaxRecvDataSegmentLength is declarative, not negotiated, and
is direction-specific so there is no reason for both ends to limit
themselves to the same min(initiator, target) value in both directions.
Allow iSCSI drivers to report their send, receive, first burst, and max
burst limits explicitly instead of using hardcoded values or trying to
derive all of them from the receive limit (which was the only limit
reported by the drivers prior to this change).
Display the send and receive limits separately in the userspace iSCSI
utilities.
Reviewed by: jpaetzel@ (earlier version), trasz@
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D7279
discovery without attaching to the targets ("iscsictl -Ad ... -e off"),
and then attach to selected ones ("iscsictl -Mi ... -e on").
PR: 204129
MFC after: 1 month
Relnotes: yes
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D6633
method. This is required for upcoming iSER support.
Obtained from: Mellanox Technologies (earlier version)
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Ensure that all iSCSI sessions are correctly terminated during shutdown.
* Enhances the changes done by r286226 (D3052).
* Add shutdown post sync event to run after filesystem shutdown
(SHUTDOWN_PRI_FIRST) but before CAM shutdown (SHUTDOWN_PRI_DEFAULT).
* Changes iscsi_maintenance_thread to processes terminate in preference to
reconnect.
Reviewed by: trasz
MFC after: 2 weeks
Sponsored by: Multiplay
Differential Revision: https://reviews.freebsd.org/D4429
r291227:
s/is->is_conn/ic to shorten things a bit.
r291228:
Do not generate PDUs with payload greater than max_data_segment_length.
It is perhaps preferable to have a separate limit for send instead of
reusing the receive limit. I'll discuss with trasz@ and mav@ before
pulling this into head.
r292618:
Add comment to go with r291228.
iscsi's shutdown_pre_sync prio was SHUTDOWN_PRI_FIRST which caused it to
run before other high priority handlers such as filesystems e.g. ZFS.
This meant the iscsi sessions where removed before the ZFS geom consumer
was closed, resulting in a panic from g_access calls on debug kernels
due to negative acr.
Instead use the same as the old iscsi_initiator SHUTDOWN_PRI_DEFAULT-1
which allows it to run before dashutdown etc but after filesystems.
MFC after: 2 weeks
Sponsored by: Multiplay
It is perhaps preferable to have a separate limit for send instead of
reusing the receive limit. I'll discuss with trasz@ and mav@ before
pulling this into head.
hangs on shutdown with LUNs with mounted filesystems over a disconnected
iSCSI session.
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D3052
initiator iSCSI offload. Pass maximum data segment size supported by
chosen offload module to iscsid(8), and make iscsid(8) not try to negotiate
anything larger than that.
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
While we don't support MCS, hole in received sequence numbers may mean
only PDU loss. While we don't support lost PDU recovery, terminate the
connection to avoid stuck commands.
While there, improve handling of sequence numbers wrap after 2^32 PDUs.
MFC after: 2 weeks
I've missed that iscsi_outstanding_remove() frees the second pointer,
so it should no longer be used. And in fact we don't really need to.
MFC after: 2 weeks
During heavy reads data copying in icl_pdu_get_data() may consume large
percent of CPU time. Moving it out of the lock significantly reduces
lock hold time and respectively lock congestion on read operations.
MFC after: 2 weeks
It allows to push out some final data from the send queue to the socket
before its close. In particular, it increases chances for logout response
to be delivered to the initiator.
in r263741. At least with CTL (slightly modified to report SPC2) there
is still some problem: it doesn't seem to find LUNs higher than 7.
Sponsored by: The FreeBSD Foundation
Previously ISID was changed every time, that made impossible correct
persistent reservation, because reconnected session was identified as
completely new one.
Reviewed by: trasz
MFC after: 1 week
These changes prevent sysctl(8) from returning proper output,
such as:
1) no output from sysctl(8)
2) erroneously returning ENOMEM with tools like truss(1)
or uname(1)
truss: can not get etype: Cannot allocate memory
there is an environment variable which shall initialize the SYSCTL
during early boot. This works for all SYSCTL types both statically and
dynamically created ones, except for the SYSCTL NODE type and SYSCTLs
which belong to VNETs. A new flag, CTLFLAG_NOFETCH, has been added to
be used in the case a tunable sysctl has a custom initialisation
function allowing the sysctl to still be marked as a tunable. The
kernel SYSCTL API is mostly the same, with a few exceptions for some
special operations like iterating childrens of a static/extern SYSCTL
node. This operation should probably be made into a factored out
common macro, hence some device drivers use this. The reason for
changing the SYSCTL API was the need for a SYSCTL parent OID pointer
and not only the SYSCTL parent OID list pointer in order to quickly
generate the sysctl path. The motivation behind this patch is to avoid
parameter loading cludges inside the OFED driver subsystem. Instead of
adding special code to the OFED driver subsystem to post-load tunables
into dynamically created sysctls, we generalize this in the kernel.
Other changes:
- Corrected a possibly incorrect sysctl name from "hw.cbb.intr_mask"
to "hw.pcic.intr_mask".
- Removed redundant TUNABLE statements throughout the kernel.
- Some minor code rewrites in connection to removing not needed
TUNABLE statements.
- Added a missing SYSCTL_DECL().
- Wrapped two very long lines.
- Avoid malloc()/free() inside sysctl string handling, in case it is
called to initialize a sysctl from a tunable, hence malloc()/free() is
not ready when sysctls from the sysctl dataset are registered.
- Bumped FreeBSD version to indicate SYSCTL API change.
MFC after: 2 weeks
Sponsored by: Mellanox Technologies
