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Kaike Wan [Thu, 24 Jan 2019 05:51:49 +0000 (21:51 -0800)]
IB/hfi1: Add interlock between TID RDMA WRITE and other requests
This locking mechanism is designed to provent vavious memory corruption
scenarios from occurring when requests are pipelined, especially when
RDMA WRITE requests are interleaved with TID RDMA READ requests:
1. READ-AFTER-READ;
2. READ-AFTER-WRITE;
3. WRITE-AFTER-READ;
4. WRITE-AFTER-WRITE.
When memory corruption is likely, a request will be held back until
previous requests have been completed.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:51:39 +0000 (21:51 -0800)]
IB/hfi1: Add TID RDMA WRITE functionality into RDMA verbs
This patch integrates TID RDMA WRITE protocol into normal RDMA verbs
framework. The TID RDMA WRITE protocol is an end-to-end protocol
between the hfi1 drivers on two OPA nodes that converts a qualified
RDMA WRITE request into a TID RDMA WRITE request to avoid data copying
on the responder side.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:51:27 +0000 (21:51 -0800)]
IB/hfi1: Add the dual leg code
The "Second Leg" of the TID RDMA WRITE protocol deals with
the transfer of data and ack packets, which are in the KDETH
PSN space, as opposed to the IB PSN space.
Therefore, the Second Leg could be considered as a separate
state machine. As such, it is handled by a different work
queue item which is scheduled along with the normal IB state
machine work item.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:51:17 +0000 (21:51 -0800)]
IB/hfi1: Add the TID second leg ACK packet builder
This patch adds the TID packet builder for the responder side, which
contains the state machine to build TID RDMA ACK packet for either
TID RDMA WRITE DATA or TID RDMA RESYNC packets.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:51:07 +0000 (21:51 -0800)]
IB/hfi1: Add the TID second leg send packet builder
To improve performance, the TID RDMA WRITE protocol is designed to
own a second leg to send data and ack packets in the KDETH PSN space.
This patch adds the packet builder for the requester side, which
contains the state machine to build TID RDMA WRITE DATA and TID
RDMA RESYNC packet.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:50:56 +0000 (21:50 -0800)]
IB/hfi1: Resend the TID RDMA WRITE DATA packets
This patch adds the logic to resend TID RDMA WRITE DATA packets.
The tracking indices will be reset properly so that the correct
TID entries will be used.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:50:46 +0000 (21:50 -0800)]
IB/hfi1: Add a function to receive TID RDMA RESYNC packet
This patch adds a function to receive TID RDMA RESYNC packet on the
responder side. The QP's hardware flow will be updated and all
allocated software flows will be updated accordingly in order to
drop all stale packets.
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:50:36 +0000 (21:50 -0800)]
IB/hfi1: Add a function to build TID RDMA RESYNC packet
This patch adds a function to build TID RDMA RESYNC packet, which is
sent by the requester to notify the responder that no TID RDMA ACK
packet has been received for a given KDETH PSN.
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:50:24 +0000 (21:50 -0800)]
IB/hfi1: Add TID RDMA retry timer
This patch adds the TID RDMA retry timer to make sure that TID RDMA
WRITE DATA packets for a segment are received successfully by the
responder. This timer is generally armed when the last TID RDMA
WRITE DATA packet for a segment is sent out and stopped when all
TID RDMA DATA packets are acknowledged.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:50:14 +0000 (21:50 -0800)]
IB/hfi1: Add a function to receive TID RDMA ACK packet
This patch adds a function to receive TID RDMA ACK packet, which could
be an acknowledge to either a TID RDMA WRITE DATA packet or an TID
RDMA RESYNC packet. For an ACK to TID RDMA WRITE DATA packet, the
request segments are completed appropriately. For an ACK to a TID
RDMA RESYNC packet, any pending segment flow information is updated
accordingly.
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:50:03 +0000 (21:50 -0800)]
IB/hfi1: Add a function to build TID RDMA ACK packet
This patch adds a function to build TID RDMA ACJ packet, which is also
in the KDETH PSN space for packet ordering. This packet is used to
acknowledge the receiving of all the TID RDMA WRITE DATA packets
before the given KDETH PSN. Similar to RC ACK packets, TID RDMA ACK
packets could also be coalesced.
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:49:51 +0000 (21:49 -0800)]
IB/hfi1: Add a function to receive TID RDMA WRITE DATA packet
This patch adds a function to receive TID RDMA WRITE DATA packet,
which is in the KDETH PSN space in packet ordering. Due to the use
of header suppression, software is generally only notified when
the last data packet for a segment is received. This patch also
adds code to handle KDETH EFLAGS errors for ingress TID RDMA WRITE
DATA packets.
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:49:41 +0000 (21:49 -0800)]
IB/hfi1: Add a function to build TID RDMA WRITE DATA packet
This patch adds a function to build TID RDMA WRITE DATA packet.
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:49:31 +0000 (21:49 -0800)]
IB/hfi1: Add a function to receive TID RDMA WRITE response
This patch adds a function to receive TID RDMA WRITE response.
The TID entries will be stored for encoding TID RDMA WRITE DATA
packet later.
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:49:19 +0000 (21:49 -0800)]
IB/hfi1: Add TID resource timer
This patch adds the TID resource timer, which is used by the responder
to free any TID resources that are allocated for TID RDMA WRITE request
and not returned by the requester after a reasonable time.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:49:09 +0000 (21:49 -0800)]
IB/hfi1: Add a function to build TID RDMA WRITE response
This patch adds the function to build TID RDMA WRITE response. The
main role of the TID RDMA WRITE RESP packet is to send TID entries
to the requester so that they can be used to encode TID RDMA WRITE
DATA packet.
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:48:59 +0000 (21:48 -0800)]
IB/hfi1: Add functions to receive TID RDMA WRITE request
This patch adds the functions to receive TID RDMA WRITE request. The
request will be stored in the QP's s_ack_queue. This patch also adds
code to handle duplicate TID RDMA WRITE request and a function to
allocate TID resources for data receiving on the responder side.
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:48:48 +0000 (21:48 -0800)]
IB/hfi1: Add an s_acked_ack_queue pointer
The s_ack_queue is managed by two pointers into the ring:
r_head_ack_queue and s_tail_ack_queue. r_head_ack_queue is the index of
where the next received request is going to be placed and s_tail_ack_queue
is the entry of the request currently being processed. This works
perfectly fine for normal Verbs as the requests are processed one at a
time and the s_tail_ack_queue is not moved until the request that it
points to is fully completed.
In this fashion, s_tail_ack_queue constantly chases r_head_ack_queue and
the two pointers can easily be used to determine "queue full" and "queue
empty" conditions.
The detection of these two conditions are imported in determining when an
old entry can safely be overwritten with a new received request and the
resources associated with the old request be safely released.
When pipelined TID RDMA WRITE is introduced into this mix, things look
very different. r_head_ack_queue is still the point at which a newly
received request will be inserted, s_tail_ack_queue is still the
currently processed request. However, with pipelined TID RDMA WRITE
requests, s_tail_ack_queue moves to the next request once all TID RDMA
WRITE responses for that request have been sent. The rest of the protocol
for a particular request is managed by other pointers specific to TID RDMA
- r_tid_tail and r_tid_ack - which point to the entries for which the next
TID RDMA DATA packets are going to arrive and the request for which
the next TID RDMA ACK packets are to be generated, respectively.
What this means is that entries in the ring, which are "behind"
s_tail_ack_queue (entries which s_tail_ack_queue has gone past) are no
longer considered complete. This is where the problem is - a newly
received request could potentially overwrite a still active TID RDMA WRITE
request.
The reason why the TID RDMA pointers trail s_tail_ack_queue is that the
normal Verbs send engine uses s_tail_ack_queue as the pointer for the next
response. Since TID RDMA WRITE responses are processed by the normal Verbs
send engine, s_tail_ack_queue had to be moved to the next entry once all
TID RDMA WRITE response packets were sent to get the desired pipelining
between requests. Doing otherwise would mean that the normal Verbs send
engine would not be able to send the TID RDMA WRITE responses for the next
TID RDMA request until the current one is fully completed.
This patch introduces the s_acked_ack_queue index to point to the next
request to complete on the responder side. For requests other than TID
RDMA WRITE, s_acked_ack_queue should always be kept in sync with
s_tail_ack_queue. For TID RDMA WRITE request, it may fall behind
s_tail_ack_queue.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:48:38 +0000 (21:48 -0800)]
IB/hfi1: Allow for extra entries in QP's s_ack_queue
The TID RDMA WRITE protocol differs from normal IB RDMA WRITE
in that TID RDMA WRITE requests do require responses, not just
ACKs.
Therefore, TID RDMA WRITE requests need to be treated as RDMA
READ requests from the point of view of the QPs' s_ack_queue.
In other words, the QPs' need to allow for TID RDMA WRITE
requests to be stored in their s_ack_queue.
However, because the user does not know anything about the TID
RDMA capability and/or protocols, these extra entries in the
queue cannot be advertized to the user.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 05:48:28 +0000 (21:48 -0800)]
IB/hfi1: Build TID RDMA WRITE request
This patch adds the functions to build TID RDMA WRITE request.
The work request opcode, packet opcode, and packet formats for TID
RDMA WRITE protocol are also defined in this patch.
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Doug Ledford [Tue, 5 Feb 2019 22:59:43 +0000 (17:59 -0500)]
Merge branch 'tid-read' into hfi1-tid
This is the series for adding TID RDMA read. Kaike put in a lot of
effort into making this more consumable for review so special thanks to
him.
Allocating resources and tracing are separated out followed by patches
which build up the read request. Then we have the patches to receive
incoming TID RDMA read requests and handle integration with the RC
protocol.
See the cover letter of the original posting for more of a detailed
overview of TID.
https://www.spinics.net/lists/linux-rdma/msg66611.html
* tid-read:
IB/hfi1: Add static trace for TID RDMA READ protocol
IB/hfi1: Enable TID RDMA READ protocol
IB/hfi1: Add interlock between a TID RDMA request and other requests
IB/hfi1: Integrate TID RDMA READ protocol into RC protocol
IB/hfi1: Increment the retry timeout value for TID RDMA READ request
IB/hfi1: Add functions for restarting TID RDMA READ request
IB/hfi1: Add TID RDMA handlers
IB/hfi1: Add functions to receive TID RDMA READ response
IB/hfi1: Add a function to build TID RDMA READ response
IB/hfi1: Add functions to receive TID RDMA READ request
IB/hfi1: Set PbcInsertHcrc for TID RDMA packets
IB/hfi1: Add functions to build TID RDMA READ request
IB/hfi1: Add static trace for flow and TID management functions
IB/hfi1: Add the counter n_tidwait
IB/hfi1: TID RDMA RcvArray programming and TID allocation
IB/hfi1: TID RDMA flow allocation
IB/hfi: Move RC functions into a header file
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:32:44 +0000 (19:32 -0800)]
IB/hfi1: Add static trace for TID RDMA READ protocol
This patch makes the following changes to the static trace:
1. Adds the decoding of TID RDMA READ packets in IB header trace;
2. Tracks qpriv->s_flags and iow_flags in qpsleepwakeup trace;
3. Adds a new event to track RC ACK receiving;
4. Adds trace events for various stages of the TID RDMA READ
protocol. These events provide a fine-grained control for monitoring
and debugging the hfi1 driver in the filed.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:32:30 +0000 (19:32 -0800)]
IB/hfi1: Enable TID RDMA READ protocol
This patch enables TID RDMA READ protocol by converting a qualified
RDMA READ request into a TID RDMA READ request internally:
(1) The TID RDMA capability must be enabled;
(2) The request must start on a 4K page boundary and all receiving
buffers must start on 4K page boundaries;
(3) The request length must be a multiple of 4K and must be larger or
equal to 256K. Each receiving buffer length must be a multiple of 4K.
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 14:36:48 +0000 (06:36 -0800)]
IB/hfi1: Add interlock between a TID RDMA request and other requests
This locking mechanism is designed to provent vavious memory corruption
scenarios from occurring when requests are pipelined, especially when
RDMA READ/WRITE requests are interleaved with TID RDMA READ/WRITE
requests:
1. READ-AFTER-READ;
2. READ-AFTER-WRITE;
3. WRITE-AFTER-READ;
When memory corruption is likely, a request will be held back until
previous requests have been completed.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:32:09 +0000 (19:32 -0800)]
IB/hfi1: Integrate TID RDMA READ protocol into RC protocol
This patch integrates the TID RDMA READ protocol into the IB RC protocol.
This protocol is an end-to-end protocol between the hfi1 drivers on two
OPA nodes that converts a qualified RDMA READ request into a TID RDMA
READ request to avoid data copying on the requester side. The following
codes are added in this patch:
- Send the TID RDMA READ request;
- Complete the TID RDMA READ send request;
- Send the TID RDMA READ response;
- Complete the TID RDMA READ request;
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:31:57 +0000 (19:31 -0800)]
IB/hfi1: Increment the retry timeout value for TID RDMA READ request
The RC retry timeout value is based on the estimated time for the
response packet to come back. However, for TID RDMA READ request, due
to the use of header suppression, the driver is normally not notified
for each incoming response packet until the last TID RDMA READ response
packet. Consequently, the retry timeout value should be extended to
cover the transaction time for the entire length of a segment (default
256K) instead of that for a single packet. This patch addresses the
issue by introducing new retry timer functions to account for multiple
packets and wrapper functions for backward compatibility.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:31:46 +0000 (19:31 -0800)]
IB/hfi1: Add functions for restarting TID RDMA READ request
This patch adds functions to retry TID RDMA READ request. Since TID RDMA
READ request could be retried from any segment boundary, it requires
a number of tracking fields in various structures and those fields
should be reset properly. The qp->s_num_rd_atomic field is reset before
retry and therefore should be incremented for each new or retried
RDMA READ or atomic request.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 14:36:34 +0000 (06:36 -0800)]
IB/hfi1: Add TID RDMA handlers
This commit adds the TID RDMA READ pointers to the receiving opcode
handlers. It also adds TID RDMA READ header sizes to header size table.
A function to print the RHF EFLAGS errors is created so that it can be
shared by both IB and TID RDMA receiving functions.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Tue, 5 Feb 2019 22:13:30 +0000 (14:13 -0800)]
IB/hfi1: Add functions to receive TID RDMA READ response
This patch adds the functions to receive TID RDMA READ response. The TID
resource information in the KDETH packet header will direct the hardware
to deliver the packet payload to the user buffer automatically and the
software will handle the packet header for the last packet of a segment
as all other packet headers are suppressed by default. The TID entries
will be freed when all packets for a segment have been received. This
patch also adds the functions to handle KDETH eflag errors, including
flow sequence and generation errors, when a TID RDMA READ response
packet is received . The flow sequence error can be recovered by software
checking of the flow sequence and will disappear when the hardware flow
is programmed with a new generation number.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:31:12 +0000 (19:31 -0800)]
IB/hfi1: Add a function to build TID RDMA READ response
This patch adds the function to build TID RDMA READ response packet.
The previously received TID resource information will be used to
build the KDETH packet, which will direct the delivery of packet payload
by hardware.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:31:02 +0000 (19:31 -0800)]
IB/hfi1: Add functions to receive TID RDMA READ request
This patch adds the functions to receive TID RDMA READ request. The TID
resource information will be stored and tracked. Duplicate request
will also be handled properly.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:30:51 +0000 (19:30 -0800)]
IB/hfi1: Set PbcInsertHcrc for TID RDMA packets
All TID RDMA packets are in KDETH packet format and therefore the
PbcInsertHcrc must be set properly before sending the packet to
hardware. Otherwise, the packets will be dropped by the receiver.
By default, HCRC is not inserted for 9B packets without KDETH, and
this patch adds that back for TID RDMA packets.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:30:40 +0000 (19:30 -0800)]
IB/hfi1: Add functions to build TID RDMA READ request
This patch adds the helper functions to build the TID RDMA READ request
on the requester side. The key is to allocate TID resources (TID flow
and TID entries) and send the resource information to the responder side
along with the read request. Since the TID resources are limited, each
TID RDMA READ request has to be split into segments with a default
segment size of 256K. A software flow is allocated to track the data
transaction for each segment. The work request opcode, packet opcode, and
packet formats for TID RDMA READ protocol are also defined in this patch.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:30:28 +0000 (19:30 -0800)]
IB/hfi1: Add static trace for flow and TID management functions
This patch adds the static trace for the flow and TID management
functions to help debugging in the filed.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:30:18 +0000 (19:30 -0800)]
IB/hfi1: Add the counter n_tidwait
This patch adds the counter n_tidwait to count the number of times the
TID resource allocator has to wait for TID resources.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:30:07 +0000 (19:30 -0800)]
IB/hfi1: TID RDMA RcvArray programming and TID allocation
TID entries are used by hfi1 hardware to receive data payload from
incoming packets directly into a user buffer and thus avoid data copying
by software. This patch implements the functions for TID allocation,
freeing, and programming TID RcvArray entries in hardware for kernel
clients. TID entries are managed via lists of TID groups similar to PSM.
Furthermore, to track TID resource allocation for each request, software
flows are also allocated and freed as needed. Since software flows
consume large amount of memory for tracking TID allocation and freeing,
it is generally desirable to allocate them dynamically in the send queue
and only for TID RDMA requests, but pre-allocate them for receive queue
because the send queue could have thousands of entries while the receive
queue has only a limited number of entries.
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Tue, 5 Feb 2019 22:13:13 +0000 (14:13 -0800)]
IB/hfi1: TID RDMA flow allocation
The hfi1 hardware flow is a hardware flow-control mechanism for a KDETH
data packet that is received on a hfi1 port. It validates the packet by
checking both the generation and sequence. Each QP that uses the TID RDMA
mechanism will allocate a hardware flow from its receiving context for
any incoming KDETH data packets.
This patch implements:
(1) a function to allocate hardware flow
(2) a function to free hardware flow
(3) a function to initialize hardware flow generation for a receiving
context
(4) a wait mechanism if the hardware flow is not available
(4) a function to remove the qp from the wait queue for hardware flow
when the qp is reset or destroyed.
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:29:44 +0000 (19:29 -0800)]
IB/hfi: Move RC functions into a header file
This patch moves some RC helper functions into a header file so that
they can be called from both RC and TID RDMA functions. In addition,
a common function for rewinding a request is created in rdmavt so that
it can be shared between qib and hfi1 driver.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Doug Ledford [Thu, 31 Jan 2019 16:56:25 +0000 (11:56 -0500)]
Merge branch 'opfn' into hfi1-tid
This series adds the OPFN feature, which is used as the negotiation
protocol by TID RDMA. This adds a totally hidden, in-band negotiation
transfer that happens on the consumer's queue pair but without the
consumer's knowledge. For that reason, things like completions for OPFN
transfers must be filtered out of the completion queue and not sent to
the consumer. This feature does not impact any consumer APIs, but does
impact the driver/driver wire API.
At a high level OPFN enables exchanging parameters between two hosts
using IB compare and swap requests to a special virtual address. The
request uses a reserved IB work request opcode (see patch 3).
* opfn:
IB/hfi1: Add static trace for OPFN
IB/hfi1: Integrate OPFN into RC transactions
IB/hfi1, IB/rdmavt: Allow for extending of QP's s_ack_queue
IB/hfi1: OPFN interface
IB/hfi1: Add OPFN helper functions for TID RDMA feature
IB/hfi1: OPFN support discovery
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 14:10:09 +0000 (06:10 -0800)]
IB/hfi1: Add static trace for OPFN
This patch adds the static trace to the OPFN code and moves tid related
static trace code into a new header file.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:21:11 +0000 (19:21 -0800)]
IB/hfi1: Integrate OPFN into RC transactions
OPFN parameter negotiation allows a pair of connected RC QPs to exchange
a set of parameters in succession. This negotiation does not commence
till the first ULP request. Because OPFN operations are operations
private to the driver, they do not generate user completions or put the
QP into error when they run out of retries. This patch integrates the
OPFN protocol into the transactions of an RC QP.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:21:01 +0000 (19:21 -0800)]
IB/hfi1, IB/rdmavt: Allow for extending of QP's s_ack_queue
The OPFN protocol uses the COMPARE_SWAP request to exchange data
between the requester and the responder and therefore needs to
be stored in the QP's s_ack_queue when the request is received
on the responder side. However, because the user does not know
anything about the OPFN protocol, this extra entry in the
queue cannot be advertised to the user. This patch adds an extra
entry in a QP's s_ack_queue.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:20:52 +0000 (19:20 -0800)]
IB/hfi1: OPFN interface
OPFN allows a pair of connected RC QPs to exchange a set of parameters
in succession. The parameter exchange itself is done using the IB compare
and swap request with a special virtual address. The request is triggered
using a reserved IB work request opcode. This patch implements the OPFN
interface to initialize, start, process, and reset the OPFN request.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kaike Wan [Thu, 24 Jan 2019 03:20:42 +0000 (19:20 -0800)]
IB/hfi1: Add OPFN helper functions for TID RDMA feature
This patch adds the OPFN helper functions to initialize, encode, decode,
and reset OPFN parameters for the TID RDMA feature.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Mitko Haralanov [Thu, 24 Jan 2019 14:09:46 +0000 (06:09 -0800)]
IB/hfi1: OPFN support discovery
OPFN (Omni Path Feature Negotiation) support discovery allows a RC QP to
announce that it supports OPFN and also discover if OPFN is supported by
the peer QP. OPFN parameter negotiation is skipped unless OPFN support is
first discovered. OPFN support is announced by claiming what was
the reserved bit in dword 1 of OmniPath modified base transport header
in requests and responses.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Mitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Michael J. Ruhl [Thu, 24 Jan 2019 03:08:29 +0000 (19:08 -0800)]
IB/{hfi1, qib, rvt} Cleanup open coded sge usage
Several locations for manipulating sges use an open coded sequence
that is covered by helper functions.
Use the appropriate helper functions.
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Michael J. Ruhl [Thu, 24 Jan 2019 03:08:19 +0000 (19:08 -0800)]
IB/{hfi1,qib}: Cleanup open coded sge sizing
Sge sizing is done in several places using an open coded method.
This can cause maintenance issues. The open coded method is
encapsulated in a helper routine. The helper was introduced with
commit:
1198fcea8a78 ("IB/hfi1, rdmavt: Move SGE state helper routines into
rdmavt")
Update all call sites that have the open coded path with the helper
routine.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Kamal Heib [Tue, 29 Jan 2019 11:55:48 +0000 (13:55 +0200)]
IB/ipoib: Make ipoib_intercept_dev_id_attr() static
The function ipoib_intercept_dev_id_attr() is only used in ipoib_main.c
Fixes:
f6350da41dc7 ("IB/ipoib: Log sysfs 'dev_id' accesses from userspace")
Signed-off-by: Kamal Heib <kamalheib1@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Adit Ranadive [Sat, 26 Jan 2019 05:09:36 +0000 (05:09 +0000)]
RDMA/vmw_pvrdma: Support upto 64-bit PFNs
Update the driver to use the new device capability to report 64-bit UAR
PFNs.
Reviewed-by: Jorgen Hansen <jhansen@vmware.com>
Signed-off-by: Adit Ranadive <aditr@vmware.com>
Reviewed-by: Vishnu Dasa <vdasa@vmware.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Jason Gunthorpe [Tue, 29 Jan 2019 20:49:31 +0000 (13:49 -0700)]
Merge branch 'devx-async' into k.o/for-next
Yishai Hadas says:
Enable DEVX asynchronous query commands
This series enables querying a DEVX object in an asynchronous mode.
The userspace application won't block when calling the firmware and it will be
able to get the response back once that it will be ready.
To enable the above functionality:
- DEVX asynchronous command completion FD object was introduced.
- The applicable file operations were implemented to enable using it by
the user application.
- Query asynchronous method was added to the DEVX object, it will call the
firmware asynchronously and manages the response on the given input FD.
- Hot unplug support was added for the FD to work properly upon
unbind/disassociate.
- mlx5 core fence for asynchronous commands was implemented and used to
prevent racing upon unbind/disassociate.
This branch is based on mlx5-next & v5.0-rc2 due to dependencies, from
git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux
* branch 'devx-async':
IB/mlx5: Implement DEVX hot unplug for async command FD
IB/mlx5: Implement the file ops of DEVX async command FD
IB/mlx5: Introduce async DEVX obj query API
IB/mlx5: Introduce MLX5_IB_OBJECT_DEVX_ASYNC_CMD_FD
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Yishai Hadas [Tue, 22 Jan 2019 06:29:59 +0000 (08:29 +0200)]
IB/mlx5: Implement DEVX hot unplug for async command FD
Implement DEVX hot unplug for the async command FD.
This is done by managing a list of the inflight commands and wait until
all launched work is completed as part of
devx_hot_unplug_async_cmd_event_file.
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Yishai Hadas [Tue, 22 Jan 2019 06:29:58 +0000 (08:29 +0200)]
IB/mlx5: Implement the file ops of DEVX async command FD
Implement the file ops of the DEVX async command FD, this enables using
the FD for reading the events and manage other options on the FD.
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Yishai Hadas [Tue, 22 Jan 2019 06:29:57 +0000 (08:29 +0200)]
IB/mlx5: Introduce async DEVX obj query API
Introduce async DEVX obj query API to get the command response back to
user space once it's ready without blocking when calling the firmware.
The event's data includes a header with some meta data then the firmware
output command data.
The header includes:
- The input 'wr_id' to let application recognizing the response.
The input FD attribute is used to have the event data ready on.
Downstream patches from this series will implement the file ops to let
application read it.
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Yishai Hadas [Tue, 22 Jan 2019 06:29:56 +0000 (08:29 +0200)]
IB/mlx5: Introduce MLX5_IB_OBJECT_DEVX_ASYNC_CMD_FD
Introduce MLX5_IB_OBJECT_DEVX_ASYNC_CMD_FD and its initial implementation.
This object is from type class FD and will be used to read DEVX async
commands completion.
The core layer should allow the driver to set object from type FD in a
safe mode, this option was added with a matching comment in place.
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Masahiro Yamada [Fri, 25 Jan 2019 04:39:31 +0000 (13:39 +0900)]
infiniband: prefix header search paths with $(srctree)/
Currently, the Kbuild core manipulates header search paths in a crazy
way [1].
To fix this mess, I want all Makefiles to add explicit $(srctree)/ to
the search paths in the srctree. Some Makefiles are already written in
that way, but not all. The goal of this work is to make the notation
consistent, and finally get rid of the gross hacks.
Having whitespaces after -I does not matter since commit
48f6e3cf5bc6
("kbuild: do not drop -I without parameter").
[1]: https://patchwork.kernel.org/patch/
9632347/
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Parvi Kaustubhi <pkaustub@cisco.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Masahiro Yamada [Fri, 25 Jan 2019 04:39:30 +0000 (13:39 +0900)]
infiniband: remove unneeded header search paths
The included headers are located in include/target/. I was able to
build these drivers without the extra header search paths.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Yuval Avnery [Tue, 22 Jan 2019 07:02:05 +0000 (09:02 +0200)]
IB/core: Destroy QP if XRC QP fails
The open-coded variant missed destroy of SELinux created QP, reuse already
existing ib_detroy_qp() call and use this opportunity to clean
ib_create_qp() from double prints and unclear exit paths.
Reported-by: Parav Pandit <parav@mellanox.com>
Fixes:
d291f1a65232 ("IB/core: Enforce PKey security on QPs")
Signed-off-by: Yuval Avnery <yuvalav@mellanox.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Ira Weiny [Wed, 23 Jan 2019 19:02:24 +0000 (14:02 -0500)]
RDMA/qib: Use GUP longterm for PSM page pining
Similar to the core change commit
5f1d43de5416 ("IB/core: disable memory
registration of filesystem-dax vmas")
PSM should be prevented from using filesystem DAX pages.
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Yangyang Li [Tue, 18 Dec 2018 13:21:55 +0000 (21:21 +0800)]
RDMA/hns: Add timer allocation support for hip08
This patch adds qpc timer and cqc timer allocation support for hardware
timeout retransmission in kernel space driver.
Signed-off-by: Yangyang Li <liyangyang20@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Yangyang Li [Tue, 18 Dec 2018 13:21:54 +0000 (21:21 +0800)]
RDMA/hns: Add SCC context clr support for hip08
This patch adds SCC context clear support for DCQCN in kernel space
driver.
Signed-off-by: Yangyang Li <liyangyang20@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Yangyang Li [Tue, 18 Dec 2018 13:21:53 +0000 (21:21 +0800)]
RDMA/hns: Add SCC context allocation support for hip08
This patch adds SCC context allocation and initialization support for
DCQCN in kernel space driver.
Signed-off-by: Yangyang Li <liyangyang20@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Moni Shoua [Tue, 22 Jan 2019 07:16:09 +0000 (09:16 +0200)]
IB/mlx5: Remove dead code
When CONFIG_INFINIBAND_ON_DEMAND_PAGING is not set there is no caller to
ib_alloc_odp_umem() so let's remove it.
Signed-off-by: Moni Shoua <monis@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Moni Shoua [Tue, 22 Jan 2019 07:16:08 +0000 (09:16 +0200)]
IB/mlx5: Ranges in implicit ODP MR inherit its write access
A sub-range in ODP implicit MR should take its write permission from the
MR and not be set always to allow.
Fixes:
d07d1d70ce1a ("IB/umem: Update on demand page (ODP) support")
Signed-off-by: Moni Shoua <monis@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Jason Gunthorpe [Sun, 20 Jan 2019 01:27:13 +0000 (02:27 +0100)]
RDMA/iw_cxgb4: Drop __GFP_NOFAIL
There is no reason for this __GFP_NOFAIL, none of the other routines in
this file use it, and there is an error unwind here. NOFAIL should be
reserved for special cases, not used by network drivers.
Fixes:
6a0b6174d35a ("rdma/cxgb4: Add support for kernel mode SRQ's")
Reported-by: Nicholas Mc Guire <hofrat@osadl.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Bart Van Assche [Tue, 22 Jan 2019 18:24:39 +0000 (10:24 -0800)]
IB/mlx5: Declare local functions 'static'
This patch avoids that sparse complains about missing function
declarations.
Fixes:
c9990ab39b6e ("RDMA/umem: Move all the ODP related stuff out of ucontext and into per_mm")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Bart Van Assche [Tue, 22 Jan 2019 18:24:23 +0000 (10:24 -0800)]
IB/core: Declare local functions 'static'
This patch avoids that sparse complains about missing function
declarations.
Fixes:
f27a0d50a4bc ("RDMA/umem: Use umem->owning_mm inside ODP")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Greg Kroah-Hartman [Tue, 22 Jan 2019 15:18:00 +0000 (16:18 +0100)]
infiniband: ipoib: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Greg Kroah-Hartman [Tue, 22 Jan 2019 15:17:59 +0000 (16:17 +0100)]
infiniband: usnic: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Parvi Kaustubhi <pkaustub@cisco.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Greg Kroah-Hartman [Tue, 22 Jan 2019 15:17:58 +0000 (16:17 +0100)]
infiniband: ocrdma: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Greg Kroah-Hartman [Tue, 22 Jan 2019 15:17:57 +0000 (16:17 +0100)]
infiniband: mlx5: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Greg Kroah-Hartman [Tue, 22 Jan 2019 15:17:56 +0000 (16:17 +0100)]
infiniband: qib: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Greg Kroah-Hartman [Tue, 22 Jan 2019 15:17:55 +0000 (16:17 +0100)]
infiniband: hfi1: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Greg Kroah-Hartman [Tue, 22 Jan 2019 15:17:54 +0000 (16:17 +0100)]
infiniband: hfi1: drop crazy DEBUGFS_SEQ_FILE_CREATE() macro
The macro was just making things harder to follow, and audit, so remove
it and call debugfs_create_file() directly. Also, the macro did not
need to warn about the call failing as no one should ever care about any
debugfs functions failing.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Greg Kroah-Hartman [Tue, 22 Jan 2019 15:17:53 +0000 (16:17 +0100)]
infiniband: cxgb4: no need to check return value of debugfs_create functions
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Parav Pandit [Tue, 22 Jan 2019 06:31:20 +0000 (08:31 +0200)]
IB/umad: Do not check status of nonseekable_open()
As the comment block of nonseekable_open() describes, nonseekable_open()
can never fail. Several places in kernel depend on this behavior.
Therefore, simplify the umad module to depend on this basic kernel
functionality.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Michael Guralnik [Sat, 19 Jan 2019 00:33:11 +0000 (16:33 -0800)]
net/mlx5: Add pci AtomicOps request
Calling pci_enable_atomic_ops_to_root enables AtomicOp requests to pci
root port.
AtomicOp requests will be enabled only if the completer and all
intermediate pci bridges support PCI atomic operations.
This, together with appropriate settings in the NVCONFIG should enable
PCI atomic operations on the device.
PCI atomic operations were first introduced in PCI Express Base Specification
2.1. The Supported operations are Swap (Unconditional Swap), CAS (Compare and
Swap) and FetchAdd (Fetch and Add).
Unlike other atomic operation modes PCI atomic operations gives the user
the option to do atomic operations on local memory, without involving verbs
api, without it compromising the operation's atomicity.
Signed-off-by: Michael Guralnik <michaelgur@mellanox.com>
Reviewed-by: Majd Dibbiny <majd@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Jason Gunthorpe [Sat, 19 Jan 2019 00:33:10 +0000 (16:33 -0800)]
net/mlx5: Make mlx5_cmd_exec_cb() a safe API
APIs that have deferred callbacks should have some kind of cleanup
function that callers can use to fence the callbacks. Otherwise things
like module unloading can lead to dangling function pointers, or worse.
The IB MR code is the only place that calls this function and had a
really poor attempt at creating this fence. Provide a good version in
the core code as future patches will add more places that need this
fence.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Parav Pandit [Tue, 22 Jan 2019 06:33:00 +0000 (08:33 +0200)]
IB/umad: Avoid additional device reference during open()/close()
ib_umad_init_port_dev() holds the reference of a ib_umad_device instance.
ib_umad_device contains standard core device and cdev. cdev holds the
reference of its parent core device. file ops holds the reference to cdev
using core kernel.
Therefore, there is no need to hold additional reference while opening
umad related char devices.
While at it, add comments to bring clarity on releasing references to
ib_umd_device.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Maor Gottlieb [Thu, 17 Jan 2019 18:08:15 +0000 (20:08 +0200)]
IB/mlx5: Don't override existing ip_protocol
Two flow specifications can set the ip protocol field in
the flow table entry:
1) IB_FLOW_SPEC_TCP/UDP/GRE - set the ip protocol accordingly.
2) IB_FLOW_SPEC_IPV4/6 - has ip_protocol field for users
who want to receive specific L4 packets.
We need to avoid overriding of the ip_protocol with zeros,
in case that the user first put the L4 specification and
only then the L3.
Fixes:
ca0d47538528b ('IB/mlx5: Add support in TOS and protocol to flow steering')
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Yishai Hadas [Sun, 13 Jan 2019 14:01:18 +0000 (16:01 +0200)]
IB/mlx5: Add support for ODP for DEVX indirection mkey
Add support for ODP for DEVX indirection mkey, it includes:
- Recognizing its type as part of the radix tree lookup.
- Use similar flow as done for the MW MKEY type.
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Yishai Hadas [Sun, 13 Jan 2019 14:01:17 +0000 (16:01 +0200)]
IB/mlx5: Manage indirection mkey upon DEVX flow for ODP
Manage indirection mkey upon DEVX flow to support ODP.
To support a page fault event on the indirection mkey it needs to be part
of the device mkey radix tree.
Both the creation and the deletion flows for a DEVX object which is
indirection mkey were adapted to handle that.
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Yishai Hadas [Sun, 13 Jan 2019 14:01:16 +0000 (16:01 +0200)]
IB/mlx5: DEVX handling for indirection MKEY
Once an indirection MKEY is created umem valid bit shouldn't be set as
this MKEY doesn't really hold a umem.
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Reviewed-by: Artemy Kovalyov <artemyko@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Xiaofei Tan [Sat, 19 Jan 2019 06:23:29 +0000 (14:23 +0800)]
RDMA/hns: Add the process of AEQ overflow for hip08
AEQ overflow will be reported by hardware when too many asynchronous
events occurred but not be handled in time. Normally, AEQ overflow error
is not easy to occur. Once happened, we have to do physical function reset
to recover. PF reset is implemented in two steps. Firstly, set reset
level with ae_dev->ops->set_default_reset_request. Secondly, run reset
with ae_dev->ops->reset_event.
Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: Yixian Liu <liuyixian@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Zhu Yanjun [Sun, 20 Jan 2019 13:21:40 +0000 (08:21 -0500)]
IB/rxe: Remove unnecessary rxe variable
The variable rxe in the function is not used. So it is removed.
Signed-off-by: Zhu Yanjun <yanjun.zhu@oracle.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Israel Rukshin [Thu, 17 Jan 2019 15:45:45 +0000 (15:45 +0000)]
IB/iser: Pass the correct number of entries for dma mapped SGL
ib_dma_map_sg() augments the SGL into a 'dma mapped SGL'. This process may
change the number of entries and the lengths of each entry.
Code that touches dma_address is iterating over the 'dma mapped SGL' and
must use dma_nents which returned from ib_dma_map_sg().
ib_sg_to_pages() and ib_map_mr_sg() are using dma_address so they must use
dma_nents.
Fixes:
39405885005a ("IB/iser: Port to new fast registration API")
Fixes:
bfe066e256d5 ("IB/iser: Reuse ib_sg_to_pages")
Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
YueHaibing [Fri, 18 Jan 2019 03:09:00 +0000 (11:09 +0800)]
IB/hw: Remove unneeded semicolons
Remove unneeded semicolons.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Mike Marciniszyn [Thu, 17 Jan 2019 20:41:43 +0000 (12:41 -0800)]
IB/rdmavt: Add wc_flags and wc_immdata to cq entry trace
These fields were missing from the trace. Add them.
Fixes:
c6ad9482fcb8 ("IB/rdmavt: Add tracing for cq entry and poll")
Reviewed-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Parav Pandit [Thu, 17 Jan 2019 18:14:15 +0000 (20:14 +0200)]
IB/core: Simplify rdma cgroup registration
RDMA cgroup registration routine always returns success, so simplify
function to be void and run clang formatter over whole CONFIG_CGROUP_RDMA
art of core_priv.h.
This reduces unwinding error path for regular registration and future net
namespace change functionality for rdma device.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
YueHaibing [Thu, 17 Jan 2019 03:21:47 +0000 (03:21 +0000)]
RDMA/qedr: remove set but not used variable 'ib_ctx'
Fixes gcc '-Wunused-but-set-variable' warning:
drivers/infiniband/hw/qedr/verbs.c: In function 'qedr_create_srq':
drivers/infiniband/hw/qedr/verbs.c:1436:22: warning:
variable 'ib_ctx' set but not used [-Wunused-but-set-variable]
drivers/infiniband/hw/qedr/verbs.c: In function 'qedr_create_user_qp':
drivers/infiniband/hw/qedr/verbs.c:1701:22: warning:
variable 'ib_ctx' set but not used [-Wunused-but-set-variable]
Fixes:
b0ea0fa5435f ("IB/{core,hw}: Have ib_umem_get extract the ib_ucontext from ib_udata")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Jason Gunthorpe [Sat, 12 Jan 2019 02:42:42 +0000 (02:42 +0000)]
RDMA/device: Use __ib_device_get_by_name() in ib_device_rename()
No reason to open code this loop.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Lijun Ou [Sat, 12 Jan 2019 10:36:29 +0000 (18:36 +0800)]
RDMA/hns: RDMA/hns: Assign rq head pointer when enable rq record db
When flush cqe, it needs to get the pointer of rq and sq from db address
space of user and update it into qp context by modified qp. if rq does not
exist, it will not get the value from db address space of user.
Signed-off-by: Lijun Ou <oulijun@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Gustavo A. R. Silva [Tue, 15 Jan 2019 06:00:48 +0000 (00:00 -0600)]
RDMA/mlx5: Replace kzalloc with kcalloc
Replace kzalloc() function with its 2-factor argument form, kcalloc().
This patch replaces cases of:
kzalloc(a * b, gfp)
with:
kcalloc(a, b, gfp)
This code was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Raju Rangoju [Fri, 11 Jan 2019 14:57:18 +0000 (20:27 +0530)]
RDMA/iw_cxgb4: Fix the unchecked ep dereference
The patch
944661dd97f4: "RDMA/iw_cxgb4: atomically lookup ep and get a
reference" from May 6, 2016, leads to the following Smatch complaint:
drivers/infiniband/hw/cxgb4/cm.c:2953 terminate()
error: we previously assumed 'ep' could be null (see line 2945)
Fixes:
944661dd97f4 ("RDMA/iw_cxgb4: atomically lookup ep and get a reference")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Raju Rangoju <rajur@chelsio.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Leon Romanovsky [Sun, 13 Jan 2019 13:57:04 +0000 (15:57 +0200)]
RDMA/mad: Reduce MAD scope to mlx5_ib only
Management Datagram Interface (MAD) is applicable
only when physical port is Infiniband. It makes MAD
command logic to be completely unrelated to eth/core
parts of mlx5.
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Jason Gunthorpe <jgg@mellanox.com>
Myungho Jung [Thu, 10 Jan 2019 06:27:31 +0000 (22:27 -0800)]
RDMA/cma: Rollback source IP address if failing to acquire device
If cma_acquire_dev_by_src_ip() returns error in addr_handler(), the
device state changes back to RDMA_CM_ADDR_BOUND but the resolved source
IP address is still left. After that, if rdma_destroy_id() is called
after rdma_listen(), the device is freed without removed from
listen_any_list in cma_cancel_operation(). Revert to the previous IP
address if acquiring device fails.
Reported-by: syzbot+f3ce716af730c8f96637@syzkaller.appspotmail.com
Signed-off-by: Myungho Jung <mhjungk@gmail.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Dan Carpenter [Thu, 10 Jan 2019 13:00:19 +0000 (16:00 +0300)]
RDMA/bnxt_re: fix a size calculation
This is from static analysis not from testing. Depending on the value
of rcfw->cmdq_depth, then this might not cause an issue at runtime.
The BITS_TO_LONGS() macro tells us how many longs it take to hold a
bitmap. In other words, it divides by the number if bits per long and
rounds up. Then we want to take that number and multiple by
sizeof(long) to get the number of bytes to allocate.
The code here does the multiplication first so the rounding up is done
in the wrong place. So imagine we want to allocate 1 bit, then
"(1 * 8) / 64 = 1" when we round up. But it should be
"(1 / 64) * 8 = 8". In other words, because of the rounding difference
we might allocate up to "sizeof(long) - 1" bytes fewer than intended.
Fixes:
1ac5a4047975 ("RDMA/bnxt_re: Add bnxt_re RoCE driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-By: Devesh Sharma <devesh.sharma@broadcom.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Parav Pandit [Tue, 18 Dec 2018 12:15:56 +0000 (14:15 +0200)]
RDMA: Introduce and use rdma_device_to_ibdev()
Introduce and use rdma_device_to_ibdev() API for those drivers which are
registering one sysfs group and also use in ib_core.
In subsequent patch, device->provider_ibdev one-to-one mapping is no
longer holds true during accessing sysfs entries.
Therefore, introduce an API rdma_device_to_ibdev() that provides such
information.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Parav Pandit [Tue, 18 Dec 2018 12:28:30 +0000 (14:28 +0200)]
RDMA: Rename port_callback to init_port
Most provider routines are callback routines which ib core invokes.
_callback suffix doesn't convey information about when such callback is
invoked. Therefore, rename port_callback to init_port.
Additionally, store the init_port function pointer in ib_device_ops, so
that it can be accessed in subsequent patches when binding rdma device to
net namespace.
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Linus Torvalds [Sun, 13 Jan 2019 22:41:12 +0000 (10:41 +1200)]
Linux 5.0-rc2
Jonathan Neuschäfer [Sat, 12 Jan 2019 17:14:30 +0000 (18:14 +0100)]
kernel/sys.c: Clarify that UNAME26 does not generate unique versions anymore
UNAME26 is a mechanism to report Linux's version as 2.6.x, for
compatibility with old/broken software. Due to the way it is
implemented, it would have to be updated after 5.0, to keep the
resulting versions unique. Linus Torvalds argued:
"Do we actually need this?
I'd rather let it bitrot, and just let it return random versions. It
will just start again at 2.4.60, won't it?
Anybody who uses UNAME26 for a 5.x kernel might as well think it's
still 4.x. The user space is so old that it can't possibly care about
differences between 4.x and 5.x, can it?
The only thing that matters is that it shows "2.4.<largeenough>",
which it will do regardless"
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>