Commit Graph

76 Commits

Author SHA1 Message Date
Linus Torvalds
747c19eb75 RDMA v5.17 merge window pull request
Substantially all bug fixes and cleanups:
 
 - Update drivers to use common helpers for GUIDs, pkeys, bitmaps,
   memset_startat, and others
 
 - General code cleanups from bots
 
 - Simplify some of the rxe pool code in preparation for a larger rework
 
 - Clean out old stuff from hns, including all support for hip06 devices
 
 - Fix a bug where GID table entries could be missed if the table had holes
   in it
 
 - Rename paths and sessions in rtrs for better understandability
 
 - Consolidate the roce source port selection code
 
 - NDR speed support in mlx5
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Pull rdma updates from Jason Gunthorpe:
 "Another small cycle. Mostly cleanups and bug fixes, quite a bit
  assisted from bots. There are a few new syzkaller splats that haven't
  been solved yet but they should get into the rcs in a few weeks, I
  think.

  Summary:

   - Update drivers to use common helpers for GUIDs, pkeys, bitmaps,
     memset_startat, and others

   - General code cleanups from bots

   - Simplify some of the rxe pool code in preparation for a larger
     rework

   - Clean out old stuff from hns, including all support for hip06
     devices

   - Fix a bug where GID table entries could be missed if the table had
     holes in it

   - Rename paths and sessions in rtrs for better understandability

   - Consolidate the roce source port selection code

   - NDR speed support in mlx5"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (83 commits)
  RDMA/irdma: Remove the redundant return
  RDMA/rxe: Use the standard method to produce udp source port
  RDMA/irdma: Make the source udp port vary
  RDMA/hns: Replace get_udp_sport with rdma_get_udp_sport
  RDMA/core: Calculate UDP source port based on flow label or lqpn/rqpn
  IB/qib: Fix typos
  RDMA/rtrs-clt: Rename rtrs_clt to rtrs_clt_sess
  RDMA/rtrs-srv: Rename rtrs_srv to rtrs_srv_sess
  RDMA/rtrs-clt: Rename rtrs_clt_sess to rtrs_clt_path
  RDMA/rtrs-srv: Rename rtrs_srv_sess to rtrs_srv_path
  RDMA/rtrs: Rename rtrs_sess to rtrs_path
  RDMA/hns: Modify the hop num of HIP09 EQ to 1
  IB/iser: Align coding style across driver
  IB/iser: Remove un-needed casting to/from void pointer
  IB/iser: Don't suppress send completions
  IB/iser: Rename ib_ret local variable
  IB/iser: Fix RNR errors
  IB/iser: Remove deprecated pi_guard module param
  IB/mlx5: Expose NDR speed through MAD
  RDMA/cxgb4: Set queue pair state when being queried
  ...
2022-01-13 11:09:11 -08:00
Vaishali Thakkar
f3433d79cd RDMA/rtrs-clt: Rename rtrs_clt to rtrs_clt_sess
Structure rtrs_clt is used for sessions. So to avoid confusions rename it
to rtrs_clt_sess.

Transformations are done with the help of following coccinelle script.

@@
@@
struct
- rtrs_clt
+ rtrs_clt_sess

Link: https://lore.kernel.org/r/20220105180708.7774-6-jinpu.wang@ionos.com
Signed-off-by: Vaishali Thakkar <vaishali.thakkar@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2022-01-07 10:07:31 -04:00
Vaishali Thakkar
f7ecac6a09 RDMA/rtrs-srv: Rename rtrs_srv to rtrs_srv_sess
Structure rtrs_srv is used for sessions so in order to avoid confusions
rename it to rtrs_srv_sess.

All changes were done with the help of following Coccinelle script:

@@
@@
struct
- rtrs_srv
+ rtrs_srv_sess

Link: https://lore.kernel.org/r/20220105180708.7774-5-jinpu.wang@ionos.com
Signed-off-by: Vaishali Thakkar <vaishali.thakkar@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2022-01-07 10:07:31 -04:00
Vaishali Thakkar
ae4c81644e RDMA/rtrs-srv: Rename rtrs_srv_sess to rtrs_srv_path
rtrs_srv_sess is used for paths and not sessions on the server side. This
creates confusion so let's rename it to rtrs_srv_path. Also, rename
related variables and functions.

Coccinelle is used to do the transformations for most of the occurrences
and remaining ones were handled manually.

Link: https://lore.kernel.org/r/20220105180708.7774-3-jinpu.wang@ionos.com
Signed-off-by: Vaishali Thakkar <vaishali.thakkar@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2022-01-07 10:07:31 -04:00
Greg Kroah-Hartman
050f461e28 block/rnbd-clt-sysfs: use default_groups in kobj_type
There are currently 2 ways to create a set of sysfs files for a
kobj_type, through the default_attrs field, and the default_groups
field.  Move the rnbd controller sysfs code to use default_groups field
which has been the preferred way since aa30f47cf6 ("kobject: Add
support for default attribute groups to kobj_type") so that we can soon
get rid of the obsolete default_attrs field.

Cc: "Md. Haris Iqbal" <haris.iqbal@ionos.com>
Cc: Jack Wang <jinpu.wang@ionos.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Link: https://lore.kernel.org/r/20220104162947.1320936-1-gregkh@linuxfoundation.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-01-05 12:28:19 -07:00
Christoph Hellwig
f3fa33acca block: remove the ->rq_disk field in struct request
Just use the disk attached to the request_queue instead.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20211126121802.2090656-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-11-29 06:41:29 -07:00
Luis Chamberlain
2e9e31bea0 rnbd: add error handling support for add_disk()
We never checked for errors on add_disk() as this function
returned void. Now that this is fixed, use the shiny new
error handling.

Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Link: https://lore.kernel.org/r/20211015233028.2167651-9-mcgrof@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-21 09:00:56 -06:00
Jens Axboe
5a72e899ce block: add a struct io_comp_batch argument to fops->iopoll()
struct io_comp_batch contains a list head and a completion handler, which
will allow completions to more effciently completed batches of IO.

For now, no functional changes in this patch, we just define the
io_comp_batch structure and add the argument to the file_operations iopoll
handler.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 14:40:40 -06:00
Christoph Hellwig
24b83deb29 block: move struct request to blk-mq.h
struct request is only used by blk-mq drivers, so move it and all
related declarations to blk-mq.h.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210920123328.1399408-18-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-18 06:17:02 -06:00
Dan Carpenter
7904022dec block/rnbd-clt-sysfs: fix a couple uninitialized variable bugs
These variables are printed on the error path if match_int() fails so
they have to be initialized.

Fixes: 2958a995ed ("block/rnbd-clt: Support polling mode for IO latency optimization")
Fixes: 1eb54f8f5d ("block/rnbd: client: sysfs interface functions")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Gioh Kim <gi-oh.kim@ionos.com>
Link: https://lore.kernel.org/r/20211012084443.GA31472@kili
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-10-12 10:39:57 -06:00
Md Haris Iqbal
3087b335b5 block/rnbd: Use sysfs_emit instead of s*printf function for sysfs show
sysfs_emit function was added to be aware of the PAGE_SIZE maximum of
the temporary buffer used for outputting sysfs content, so there is no
possible overruns. So replace the uses of any s*printf functions for
the sysfs show functions with sysfs_emit.

Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Link: https://lore.kernel.org/r/20210726115950.470543-3-jinpu.wang@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-02 13:37:40 -06:00
Gioh Kim
94dace8c85 block/rnbd-clt: Use put_cpu_ptr after get_cpu_ptr
This patch replaces put_cpu_var with put_cpu_ptr because
get_cpu_ptr should be paired with put_cpu_ptr.

Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Link: https://lore.kernel.org/r/20210726115950.470543-2-jinpu.wang@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-08-02 13:37:40 -06:00
Linus Torvalds
e04360a2ea RDMA v5.14 merge window Pull Request
This PR contains a replacement driver for Intel iWarp hardware. This new
 driver supports the old ethernet hardware and also newer chips that can do
 ROCE. Otherwise this contains the typical mix of patches:
 
 - Driver updates and cleanups for bnxt_re, cxgb4, mlx4, and mlx5
 
 - Many static checker driven code clean ups, including a wide refcount_t
   conversion
 
 - Several series for the hns driver, more HIP09 HW capabilities, migration
   to new HW register manipulators, and code cleanups
 
 - Minor fixes and improvements  in srp, rts, and cm
 
 - Improvements throughout for sysfs related code to use DEVICE_ATTR_*,
   make the ib_port sysfs first-class, and overall use sysfs APIs properly
 
 - Intel's new irdma driver replacing i40iw
 
 - rxe general clean ups and Memory Window support
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Pull rdma updates from Jason Gunthorpe:
 "This contains a replacement driver for Intel iWarp hardware. This new
  driver supports the old ethernet hardware and also newer chips that
  can do ROCE.

  Other than that, this contains the typical mix of patches:

   - Driver updates and cleanups for bnxt_re, cxgb4, mlx4, and mlx5

   - Many static checker driven code clean ups, including a wide
     refcount_t conversion

   - Several series for the hns driver, more HIP09 HW capabilities,
     migration to new HW register manipulators, and code cleanups

   - Minor fixes and improvements in srp, rts, and cm

   - Improvements throughout for sysfs related code to use
     DEVICE_ATTR_*, make the ib_port sysfs first-class, and overall use
     sysfs APIs properly

   - Intel's new irdma driver replacing i40iw

   - rxe general clean ups and Memory Window support"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (211 commits)
  RDMA/core: Always release restrack object
  RDMA/mlx5: Don't access NULL-cleared mpi pointer
  RDMA/irdma: Fix potential overflow expression in irdma_prm_get_pbles
  RDMA/irdma: Check contents of user-space irdma_mem_reg_req object
  RDMA/rxe: Missing unlock on error in get_srq_wqe()
  RDMA/cma: Fix rdma_resolve_route() memory leak
  RDMA/core/sa_query: Remove unused argument
  RDMA/cma: Fix incorrect Packet Lifetime calculation
  RDMA/cma: Protect RMW with qp_mutex
  RDMA/cma: Remove unnecessary INIT->INIT transition
  RDMA/hns: Add window selection field of congestion control
  RDMA/hfi1: Remove use of kmap()
  RDMA/irdma: Remove use of kmap()
  RDMA/bnxt_re: Fix uninitialized struct bit field rsvd1
  IB/isert: Align target max I/O size to initiator size
  RDMA/hns: Fix incorrect vlan enable bit in QPC
  MAINTAINERS: Update Broadcom RDMA maintainers
  RDMA/irdma: Use the queried port attributes
  RDMA/rxe: Fix redundant skb_put_zero
  RDMA/rxe: Fix extra copy in prepare_ack_packet
  ...
2021-07-01 14:54:03 -07:00
Jack Wang
7404bddeb4 rnbd/rtrs-clt: Query and use max_segments from rtrs-clt.
With fast memory registration on write request, rnbd-clt
can do bigger IO without split. rnbd-clt now can query
rtrs-clt to get the max_segments, instead of using
BMAX_SEGMENTS.

BMAX_SEGMENTS is not longer needed, so remove it.

Link: https://lore.kernel.org/r/20210621055340.11789-6-jinpu.wang@ionos.com
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: Md Haris Iqbal <haris.iqbal@cloud.ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
2021-06-21 21:02:21 -03:00
Christoph Hellwig
2c6ee0ae5f rnbd: use blk_mq_alloc_disk and blk_cleanup_disk
Use blk_mq_alloc_disk and blk_cleanup_disk to simplify the gendisk and
request_queue allocation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jack Wang <jinpu.wang@ionos.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210602065345.355274-24-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-06-11 11:54:42 -06:00
Gioh Kim
1e31016b69 block/rnbd: Remove all likely and unlikely
The IO performance test with fio after removing the likely and
unlikely macros in all if-statement shows no performance drop.
They do not help for the performance of rnbd.

The fio test did random read on 32 rnbd devices and 64 processes.
Test environment:
- AMD Opteron(tm) Processor 6386 SE
- 125G memory
- kernel version: 5.4.86
- gcc version: gcc (Debian 8.3.0-6) 8.3.0
- Infiniband controller: InfiniBand: Mellanox Technologies MT26428
[ConnectX VPI PCIe 2.0 5GT/s - IB QDR / 10GigE] (rev b0)

before
read: IOPS=549k, BW=2146MiB/s
read: IOPS=544k, BW=2125MiB/s
read: IOPS=553k, BW=2158MiB/s
read: IOPS=535k, BW=2089MiB/s
read: IOPS=543k, BW=2122MiB/s
read: IOPS=552k, BW=2154MiB/s
average: IOPS=546k, BW=2132MiB/s

after
read: IOPS=556k, BW=2172MiB/s
read: IOPS=561k, BW=2191MiB/s
read: IOPS=552k, BW=2156MiB/s
read: IOPS=551k, BW=2154MiB/s
read: IOPS=562k, BW=2194MiB/s
-----------
average: IOPS=556k, BW=2173MiB/s

The IOPS and bandwidth got better slightly after removing
likely/unlikely. (IOPS= +1.8% BW= +1.9%) But we cannot make sure
that removing the likely/unlikely help the performance because it
depends on various situations. We only make sure that removing the
likely/unlikely does not drop the performance.

Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Reviewed-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Link: https://lore.kernel.org/r/20210428061359.206794-5-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-03 11:00:11 -06:00
Md Haris Iqbal
1056ad829e block/rnbd-clt: Check the return value of the function rtrs_clt_query
In case none of the paths are in connected state, the function
rtrs_clt_query returns an error. In such a case, error out since the
values in the rtrs_attrs structure would be garbage.

Fixes: f7a7a5c228 ("block/rnbd: client: main functionality")
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Reviewed-by: Guoqing Jiang <guoqing.jiang@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Link: https://lore.kernel.org/r/20210428061359.206794-4-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-03 11:00:11 -06:00
Dima Stepanov
292660fa35 block/rnbd: Fix style issues
This patch fixes some style issues detected by scripts/checkpatch.pl
* Resolve spacing and tab issues
* Remove extra braces in rnbd_get_iu
* Use num_possible_cpus() instead of NR_CPUS in alloc_sess
* Fix the comments styling in rnbd_queue_rq

Signed-off-by: Dima Stepanov <dmitrii.stepanov@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Link: https://lore.kernel.org/r/20210428061359.206794-3-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-03 11:00:11 -06:00
Md Haris Iqbal
80d43cbd46 block/rnbd-clt: Change queue_depth type in rnbd_clt_session to size_t
The member queue_depth in the structure rnbd_clt_session is read from the
rtrs client side using the function rtrs_clt_query, which in turn is read
from the rtrs_clt structure. It should really be of type size_t.

Fixes: 90426e89f5 ("block/rnbd: client: private header with client structs and functions")
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Reviewed-by: Guoqing Jiang <guoqing.jiang@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Link: https://lore.kernel.org/r/20210428061359.206794-2-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-05-03 11:00:11 -06:00
Dima Stepanov
57b93ed435 block/rnbd: Use strscpy instead of strlcpy
During checkpatch analyzing the following warning message was found:
  WARNING:STRLCPY: Prefer strscpy over strlcpy - see:
  https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Fix it by using strscpy calls instead of strlcpy.

Signed-off-by: Dima Stepanov <dmitrii.stepanov@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210419073722.15351-20-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:04 -06:00
Dima Stepanov
3db7cf55d5 block/rnbd-clt-sysfs: Remove copy buffer overlap in rnbd_clt_get_path_name
cppcheck report the following error:
  rnbd/rnbd-clt-sysfs.c:522:36: error: The variable 'buf' is used both
  as a parameter and as destination in snprintf(). The origin and
  destination buffers overlap. Quote from glibc (C-library)
  documentation
  (http://www.gnu.org/software/libc/manual/html_mono/libc.html#Formatted-Output-Functions):
  "If copying takes place between objects that overlap as a result of a
  call to sprintf() or snprintf(), the results are undefined."
  [sprintfOverlappingData]
Fix it by initializing the buf variable in the first snprintf call.

Fixes: 91f4acb280 ("block/rnbd-clt: support mapping two devices")
Signed-off-by: Dima Stepanov <dmitrii.stepanov@ionos.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210419073722.15351-19-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:04 -06:00
Jack Wang
503438a4f2 block/rnbd-clt: Remove max_segment_size
We always map with SZ_4K, so do not need max_segment_size.

Cc: Leon Romanovsky <leonro@nvidia.com>
Cc: linux-rdma@vger.kernel.org
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Reviewed-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Acked-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/20210419073722.15351-18-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:04 -06:00
Md Haris Iqbal
3ba1c6935c block/rnbd-clt: Generate kobject_uevent when the rnbd device state changes
When an RTRS session state changes, the transport layer generates an event
to RNBD. Then RNBD will change the state of the RNBD client device
accordingly.

This commit add kobject_uevent when the RNBD device state changes. With
this udev rules can be configured to react accordingly.

Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Link: https://lore.kernel.org/r/20210419073722.15351-17-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:04 -06:00
Gioh Kim
c81cba8551 block/rnbd-srv: Remove unused arguments of rnbd_srv_rdma_ev
struct rtrs_srv is not used when handling rnbd_srv_rdma_ev messages, so
cleaned up
rdma_ev function pointer in rtrs_srv_ops also is changed.

Cc: Leon Romanovsky <leonro@nvidia.com>
Cc: linux-rdma@vger.kernel.org
Signed-off-by: Aleksei Marov <aleksei.marov@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/20210419073722.15351-16-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:04 -06:00
Gioh Kim
2958a995ed block/rnbd-clt: Support polling mode for IO latency optimization
RNBD can make double-queues for irq-mode and poll-mode.
For example, on 4-CPU system 8 request-queues are created,
4 for irq-mode and 4 for poll-mode.
If the IO has HIPRI flag, the block-layer will call .poll function
of RNBD. Then IO is sent to the poll-mode queue.
Add optional nr_poll_queues argument for map_devices interface.

To support polling of RNBD, RTRS client creates connections
for both of irq-mode and direct-poll-mode.

For example, on 4-CPU system it could've create 5 connections:
con[0] => user message (softirq cq)
con[1:4] => softirq cq

After this patch, it can create 9 connections:
con[0] => user message (softirq cq)
con[1:4] => softirq cq
con[5:8] => DIRECT-POLL cq

Cc: Leon Romanovsky <leonro@nvidia.com>
Cc: linux-rdma@vger.kernel.org
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Acked-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/20210419073722.15351-14-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:04 -06:00
Gioh Kim
12b0653310 block/rnbd-clt: Fix missing a memory free when unloading the module
When unloading the rnbd-clt module, it does not free a memory
including the filename of the symbolic link to /sys/block/rnbdX.

It is found by kmemleak as below.

unreferenced object 0xffff9f1a83d3c740 (size 16):
  comm "bash", pid 736, jiffies 4295179665 (age 9841.310s)
  hex dump (first 16 bytes):
    21 64 65 76 21 6e 75 6c 6c 62 30 40 62 6c 61 00  !dev!nullb0@bla.
  backtrace:
    [<0000000039f0c55e>] 0xffffffffc0456c24
    [<000000001aab9513>] kernfs_fop_write+0xcf/0x1c0
    [<00000000db5aa4b3>] vfs_write+0xdb/0x1d0
    [<000000007a2e2207>] ksys_write+0x65/0xe0
    [<00000000055e280a>] do_syscall_64+0x50/0x1b0
    [<00000000c2b51831>] entry_SYSCALL_64_after_hwframe+0x49/0xbe

Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Link: https://lore.kernel.org/r/20210419073722.15351-13-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:04 -06:00
Tom Rix
ce9d2b4f7b block/rnbd-clt: Improve find_or_create_sess() return check
clang static analysis reports this problem

rnbd-clt.c:1212:11: warning: Branch condition evaluates to a
  garbage value
        else if (!first)
                 ^~~~~~

This is triggered in the find_and_get_or_create_sess() call
because the variable first is not initialized and the
earlier check is specifically for

	if (sess == ERR_PTR(-ENOMEM))

This is false positive.

But the if-check can be reduced by initializing first to
false and then returning if the call to find_or_creat_sess()
does not set it to true.  When it remains false, either
sess will be valid or not.  The not case is caught by
find_and_get_or_create_sess()'s caller rnbd_clt_map_device()

	sess = find_and_get_or_create_sess(...);
	if (IS_ERR(sess))
		return ERR_CAST(sess);

Since find_and_get_or_create_sess() initializes first to false
setting it in find_or_create_sess() is not needed.

Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Link: https://lore.kernel.org/r/20210419073722.15351-12-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:04 -06:00
Gioh Kim
c77bfa8f5d block/rnbd-srv: Remove force_close file after holding a lock
We changed the rnbd_srv_sess_dev_force_close to use try-lock
because rnbd_srv_sess_dev_force_close and process_msg_close
can generate a deadlock.

Now rnbd_srv_sess_dev_force_close would do nothing
if it fails to get the lock. So removing the force_close
file should be moved to after the lock. Or the force_close
file is removed but the others are not removed.

Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Link: https://lore.kernel.org/r/20210419073722.15351-11-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:04 -06:00
Gioh Kim
b168e1d85c block/rnbd-srv: Prevent a deadlock generated by accessing sysfs in parallel
We got a warning message below.
When server tries to close one session by force, it locks the sysfs
interface and locks the srv_sess lock.
The problem is that client can send a request to close at the same time.
By close request, server locks the srv_sess lock and locks the sysfs
to remove the sysfs interfaces.

The simplest way to prevent that situation could be just use
mutex_trylock.

[  234.153965] ======================================================
[  234.154093] WARNING: possible circular locking dependency detected
[  234.154219] 5.4.84-storage #5.4.84-1+feature+linux+5.4.y+dbg+20201216.1319+b6b887b~deb10 Tainted: G           O
[  234.154381] ------------------------------------------------------
[  234.154531] kworker/1:1H/618 is trying to acquire lock:
[  234.154651] ffff8887a09db0a8 (kn->count#132){++++}, at: kernfs_remove_by_name_ns+0x40/0x80
[  234.154819]
               but task is already holding lock:
[  234.154965] ffff8887ae5f6518 (&srv_sess->lock){+.+.}, at: rnbd_srv_rdma_ev+0x144/0x1590 [rnbd_server]
[  234.155132]
               which lock already depends on the new lock.

[  234.155311]
               the existing dependency chain (in reverse order) is:
[  234.155462]
               -> #1 (&srv_sess->lock){+.+.}:
[  234.155614]        __mutex_lock+0x134/0xcb0
[  234.155761]        rnbd_srv_sess_dev_force_close+0x36/0x50 [rnbd_server]
[  234.155889]        rnbd_srv_dev_session_force_close_store+0x69/0xc0 [rnbd_server]
[  234.156042]        kernfs_fop_write+0x13f/0x240
[  234.156162]        vfs_write+0xf3/0x280
[  234.156278]        ksys_write+0xba/0x150
[  234.156395]        do_syscall_64+0x62/0x270
[  234.156513]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[  234.156632]
               -> #0 (kn->count#132){++++}:
[  234.156782]        __lock_acquire+0x129e/0x23a0
[  234.156900]        lock_acquire+0xf3/0x210
[  234.157043]        __kernfs_remove+0x42b/0x4c0
[  234.157161]        kernfs_remove_by_name_ns+0x40/0x80
[  234.157282]        remove_files+0x3f/0xa0
[  234.157399]        sysfs_remove_group+0x4a/0xb0
[  234.157519]        rnbd_srv_destroy_dev_session_sysfs+0x19/0x30 [rnbd_server]
[  234.157648]        rnbd_srv_rdma_ev+0x14c/0x1590 [rnbd_server]
[  234.157775]        process_io_req+0x29a/0x6a0 [rtrs_server]
[  234.157924]        __ib_process_cq+0x8c/0x100 [ib_core]
[  234.158709]        ib_cq_poll_work+0x31/0xb0 [ib_core]
[  234.158834]        process_one_work+0x4e5/0xaa0
[  234.158958]        worker_thread+0x65/0x5c0
[  234.159078]        kthread+0x1e0/0x200
[  234.159194]        ret_from_fork+0x24/0x30
[  234.159309]
               other info that might help us debug this:

[  234.159513]  Possible unsafe locking scenario:

[  234.159658]        CPU0                    CPU1
[  234.159775]        ----                    ----
[  234.159891]   lock(&srv_sess->lock);
[  234.160005]                                lock(kn->count#132);
[  234.160128]                                lock(&srv_sess->lock);
[  234.160250]   lock(kn->count#132);
[  234.160364]
                *** DEADLOCK ***

[  234.160536] 3 locks held by kworker/1:1H/618:
[  234.160677]  #0: ffff8883ca1ed528 ((wq_completion)ib-comp-wq){+.+.}, at: process_one_work+0x40a/0xaa0
[  234.160840]  #1: ffff8883d2d5fe10 ((work_completion)(&cq->work)){+.+.}, at: process_one_work+0x40a/0xaa0
[  234.161003]  #2: ffff8887ae5f6518 (&srv_sess->lock){+.+.}, at: rnbd_srv_rdma_ev+0x144/0x1590 [rnbd_server]
[  234.161168]
               stack backtrace:
[  234.161312] CPU: 1 PID: 618 Comm: kworker/1:1H Tainted: G           O      5.4.84-storage #5.4.84-1+feature+linux+5.4.y+dbg+20201216.1319+b6b887b~deb10
[  234.161490] Hardware name: Supermicro H8QG6/H8QG6, BIOS 3.00       09/04/2012
[  234.161643] Workqueue: ib-comp-wq ib_cq_poll_work [ib_core]
[  234.161765] Call Trace:
[  234.161910]  dump_stack+0x96/0xe0
[  234.162028]  check_noncircular+0x29e/0x2e0
[  234.162148]  ? print_circular_bug+0x100/0x100
[  234.162267]  ? register_lock_class+0x1ad/0x8a0
[  234.162385]  ? __lock_acquire+0x68e/0x23a0
[  234.162505]  ? trace_event_raw_event_lock+0x190/0x190
[  234.162626]  __lock_acquire+0x129e/0x23a0
[  234.162746]  ? register_lock_class+0x8a0/0x8a0
[  234.162866]  lock_acquire+0xf3/0x210
[  234.162982]  ? kernfs_remove_by_name_ns+0x40/0x80
[  234.163127]  __kernfs_remove+0x42b/0x4c0
[  234.163243]  ? kernfs_remove_by_name_ns+0x40/0x80
[  234.163363]  ? kernfs_fop_readdir+0x3b0/0x3b0
[  234.163482]  ? strlen+0x1f/0x40
[  234.163596]  ? strcmp+0x30/0x50
[  234.163712]  kernfs_remove_by_name_ns+0x40/0x80
[  234.163832]  remove_files+0x3f/0xa0
[  234.163948]  sysfs_remove_group+0x4a/0xb0
[  234.164068]  rnbd_srv_destroy_dev_session_sysfs+0x19/0x30 [rnbd_server]
[  234.164196]  rnbd_srv_rdma_ev+0x14c/0x1590 [rnbd_server]
[  234.164345]  ? _raw_spin_unlock_irqrestore+0x43/0x50
[  234.164466]  ? lockdep_hardirqs_on+0x1a8/0x290
[  234.164597]  ? mlx4_ib_poll_cq+0x927/0x1280 [mlx4_ib]
[  234.164732]  ? rnbd_get_sess_dev+0x270/0x270 [rnbd_server]
[  234.164859]  process_io_req+0x29a/0x6a0 [rtrs_server]
[  234.164982]  ? rnbd_get_sess_dev+0x270/0x270 [rnbd_server]
[  234.165130]  __ib_process_cq+0x8c/0x100 [ib_core]
[  234.165279]  ib_cq_poll_work+0x31/0xb0 [ib_core]
[  234.165404]  process_one_work+0x4e5/0xaa0
[  234.165550]  ? pwq_dec_nr_in_flight+0x160/0x160
[  234.165675]  ? do_raw_spin_lock+0x119/0x1d0
[  234.165796]  worker_thread+0x65/0x5c0
[  234.165914]  ? process_one_work+0xaa0/0xaa0
[  234.166031]  kthread+0x1e0/0x200
[  234.166147]  ? kthread_create_worker_on_cpu+0xc0/0xc0
[  234.166268]  ret_from_fork+0x24/0x30
[  234.251591] rnbd_server L243: </dev/loop1@close_device_session>: Device closed
[  234.604221] rnbd_server L264: RTRS Session close_device_session disconnected

Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Link: https://lore.kernel.org/r/20210419073722.15351-10-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:04 -06:00
Gioh Kim
9f455eeafd block/rnbd-clt: Replace {NO_WAIT,WAIT} with RTRS_PERMIT_{WAIT,NOWAIT}
They are defined with the same value and similar meaning, let's remove
one of them, then we can remove {WAIT,NOWAIT}.

Also change the type of 'wait' from 'int' to 'enum wait_type' to make
it clear.

Cc: Leon Romanovsky <leonro@nvidia.com>
Cc: linux-rdma@vger.kernel.org
Signed-off-by: Guoqing Jiang <guoqing.jiang@ionos.com>
Reviewed-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Link: https://lore.kernel.org/r/20210419073722.15351-9-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:04 -06:00
Guoqing Jiang
d16b5ac874 block/rnbd: Kill destroy_device_cb
We can use destroy_device directly since destroy_device_cb is just the
wrapper of destroy_device.

Signed-off-by: Guoqing Jiang <guoqing.jiang@ionos.com>
Reviewed-by: Danil Kipnis <danil.kipnis@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210419073722.15351-8-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:04 -06:00
Guoqing Jiang
8e43c90a26 block/rnbd: Kill rnbd_clt_destroy_default_group
No need to have it since we can call sysfs_remove_group in the
rnbd_clt_destroy_sysfs_files.

Then rnbd_clt_destroy_sysfs_files is paired with it's counterpart
rnbd_clt_create_sysfs_files.

Signed-off-by: Guoqing Jiang <guoqing.jiang@ionos.com>
Reviewed-by: Danil Kipnis <danil.kipnis@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210419073722.15351-7-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:04 -06:00
Guoqing Jiang
d0a70ab10b block/rnbd-clt: Move add_disk(dev->gd) to rnbd_clt_setup_gen_disk
It makes more sense to add gendisk in rnbd_clt_setup_gen_disk, instead
of do it in rnbd_clt_map_device.

Signed-off-by: Guoqing Jiang <guoqing.jiang@gmx.com>
Reviewed-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210419073722.15351-6-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:04 -06:00
Guoqing Jiang
8b7f05114b block/rnbd-clt: Remove some arguments from rnbd_client_setup_device
Remove them since both sess and idx can be dereferenced from dev. And
sess is not used in the function.

Signed-off-by: Guoqing Jiang <guoqing.jiang@gmx.com>
Reviewed-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210419073722.15351-5-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:03 -06:00
Guoqing Jiang
02ee80f5fe block/rnbd-clt: Remove some arguments from insert_dev_if_not_exists_devpath
Remove 'pathname' and 'sess' since we can dereference it from 'dev'.

Signed-off-by: Guoqing Jiang <guoqing.jiang@gmx.com>
Reviewed-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Link: https://lore.kernel.org/r/20210419073722.15351-4-gi-oh.kim@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-04-20 08:59:03 -06:00
Jack Wang
3a21777c6e block/rnbd-clt: avoid module unload race with close confirmation
We had kernel panic, it is caused by unload module and last
close confirmation.

call trace:
[1196029.743127]  free_sess+0x15/0x50 [rtrs_client]
[1196029.743128]  rtrs_clt_close+0x4c/0x70 [rtrs_client]
[1196029.743129]  ? rnbd_clt_unmap_device+0x1b0/0x1b0 [rnbd_client]
[1196029.743130]  close_rtrs+0x25/0x50 [rnbd_client]
[1196029.743131]  rnbd_client_exit+0x93/0xb99 [rnbd_client]
[1196029.743132]  __x64_sys_delete_module+0x190/0x260

And in the crashdump confirmation kworker is also running.
PID: 6943   TASK: ffff9e2ac8098000  CPU: 4   COMMAND: "kworker/4:2"
 #0 [ffffb206cf337c30] __schedule at ffffffff9f93f891
 #1 [ffffb206cf337cc8] schedule at ffffffff9f93fe98
 #2 [ffffb206cf337cd0] schedule_timeout at ffffffff9f943938
 #3 [ffffb206cf337d50] wait_for_completion at ffffffff9f9410a7
 #4 [ffffb206cf337da0] __flush_work at ffffffff9f08ce0e
 #5 [ffffb206cf337e20] rtrs_clt_close_conns at ffffffffc0d5f668 [rtrs_client]
 #6 [ffffb206cf337e48] rtrs_clt_close at ffffffffc0d5f801 [rtrs_client]
 #7 [ffffb206cf337e68] close_rtrs at ffffffffc0d26255 [rnbd_client]
 #8 [ffffb206cf337e78] free_sess at ffffffffc0d262ad [rnbd_client]
 #9 [ffffb206cf337e88] rnbd_clt_put_dev at ffffffffc0d266a7 [rnbd_client]

The problem is both code path try to close same session, which lead to
panic.

To fix it, just skip the sess if the refcount already drop to 0.

Fixes: f7a7a5c228 ("block/rnbd: client: main functionality")
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-08 08:19:18 -07:00
Swapnil Ingle
ef8048dd23 block/rnbd: Adding name to the Contributors List
Adding name to the Contributors List

Signed-off-by: Swapnil Ingle <ingleswapnil@gmail.com>
Acked-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Acked-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-08 08:19:18 -07:00
Guoqing Jiang
80f99093d8 block/rnbd-clt: Fix sg table use after free
Since dynamically allocate sglist is used for rnbd_iu, we can't free sg
table after send_usr_msg since the callback function (cqe.done) could
still access the sglist.

Otherwise KASAN reports UAF issue:

[ 4856.600257] BUG: KASAN: use-after-free in dma_direct_unmap_sg+0x53/0x290
[ 4856.600772] Read of size 4 at addr ffff888206af3a98 by task swapper/1/0

[ 4856.601729] CPU: 1 PID: 0 Comm: swapper/1 Kdump: loaded Tainted: G        W         5.10.0-pserver #5.10.0-1+feature+linux+next+20201214.1025+0910d71
[ 4856.601748] Hardware name: Supermicro Super Server/X11DDW-L, BIOS 3.3 02/21/2020
[ 4856.601766] Call Trace:
[ 4856.601785]  <IRQ>
[ 4856.601822]  dump_stack+0x99/0xcb
[ 4856.601856]  ? dma_direct_unmap_sg+0x53/0x290
[ 4856.601888]  print_address_description.constprop.7+0x1e/0x230
[ 4856.601913]  ? freeze_kernel_threads+0x73/0x73
[ 4856.601965]  ? mark_held_locks+0x29/0xa0
[ 4856.602019]  ? dma_direct_unmap_sg+0x53/0x290
[ 4856.602039]  ? dma_direct_unmap_sg+0x53/0x290
[ 4856.602079]  kasan_report.cold.9+0x37/0x7c
[ 4856.602188]  ? mlx5_ib_post_recv+0x430/0x520 [mlx5_ib]
[ 4856.602209]  ? dma_direct_unmap_sg+0x53/0x290
[ 4856.602256]  dma_direct_unmap_sg+0x53/0x290
[ 4856.602366]  complete_rdma_req+0x188/0x4b0 [rtrs_client]
[ 4856.602451]  ? rtrs_clt_close+0x80/0x80 [rtrs_client]
[ 4856.602535]  ? mlx5_ib_poll_cq+0x48b/0x16e0 [mlx5_ib]
[ 4856.602589]  ? radix_tree_insert+0x3a0/0x3a0
[ 4856.602610]  ? do_raw_spin_lock+0x119/0x1d0
[ 4856.602647]  ? rwlock_bug.part.1+0x60/0x60
[ 4856.602740]  rtrs_clt_rdma_done+0x3f7/0x670 [rtrs_client]
[ 4856.602804]  ? rtrs_clt_rdma_cm_handler+0xda0/0xda0 [rtrs_client]
[ 4856.602857]  ? check_flags.part.31+0x6c/0x1f0
[ 4856.602927]  ? rcu_read_lock_sched_held+0xaf/0xe0
[ 4856.602963]  ? rcu_read_lock_bh_held+0xc0/0xc0
[ 4856.603137]  __ib_process_cq+0x10a/0x350 [ib_core]
[ 4856.603309]  ib_poll_handler+0x41/0x1c0 [ib_core]
[ 4856.603358]  irq_poll_softirq+0xe6/0x280
[ 4856.603392]  ? lockdep_hardirqs_on_prepare+0x111/0x210
[ 4856.603446]  __do_softirq+0x10d/0x646
[ 4856.603540]  asm_call_irq_on_stack+0x12/0x20
[ 4856.603563]  </IRQ>

[ 4856.605096] Allocated by task 8914:
[ 4856.605510]  kasan_save_stack+0x19/0x40
[ 4856.605532]  __kasan_kmalloc.constprop.7+0xc1/0xd0
[ 4856.605552]  __kmalloc+0x155/0x320
[ 4856.605574]  __sg_alloc_table+0x155/0x1c0
[ 4856.605594]  sg_alloc_table+0x1f/0x50
[ 4856.605620]  send_msg_sess_info+0x119/0x2e0 [rnbd_client]
[ 4856.605646]  remap_devs+0x71/0x210 [rnbd_client]
[ 4856.605676]  init_sess+0xad8/0xe10 [rtrs_client]
[ 4856.605706]  rtrs_clt_reconnect_work+0xd6/0x170 [rtrs_client]
[ 4856.605728]  process_one_work+0x521/0xa90
[ 4856.605748]  worker_thread+0x65/0x5b0
[ 4856.605769]  kthread+0x1f2/0x210
[ 4856.605789]  ret_from_fork+0x22/0x30

[ 4856.606159] Freed by task 8914:
[ 4856.606559]  kasan_save_stack+0x19/0x40
[ 4856.606580]  kasan_set_track+0x1c/0x30
[ 4856.606601]  kasan_set_free_info+0x1b/0x30
[ 4856.606622]  __kasan_slab_free+0x108/0x150
[ 4856.606642]  slab_free_freelist_hook+0x64/0x190
[ 4856.606661]  kfree+0xe2/0x650
[ 4856.606681]  __sg_free_table+0xa4/0x100
[ 4856.606707]  send_msg_sess_info+0x1d6/0x2e0 [rnbd_client]
[ 4856.606733]  remap_devs+0x71/0x210 [rnbd_client]
[ 4856.606763]  init_sess+0xad8/0xe10 [rtrs_client]
[ 4856.606792]  rtrs_clt_reconnect_work+0xd6/0x170 [rtrs_client]
[ 4856.606813]  process_one_work+0x521/0xa90
[ 4856.606833]  worker_thread+0x65/0x5b0
[ 4856.606853]  kthread+0x1f2/0x210
[ 4856.606872]  ret_from_fork+0x22/0x30

The solution is to free iu's sgtable after the iu is not used anymore.
And also move sg_alloc_table into rnbd_get_iu accordingly.

Fixes: 5a1328d0c3 ("block/rnbd-clt: Dynamically allocate sglist for rnbd_iu")
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-08 08:19:18 -07:00
Jack Wang
1a84e7c629 block/rnbd-srv: Fix use after free in rnbd_srv_sess_dev_force_close
KASAN detect following BUG:
[  778.215311] ==================================================================
[  778.216696] BUG: KASAN: use-after-free in rnbd_srv_sess_dev_force_close+0x38/0x60 [rnbd_server]
[  778.219037] Read of size 8 at addr ffff88b1d6516c28 by task tee/8842

[  778.220500] CPU: 37 PID: 8842 Comm: tee Kdump: loaded Not tainted 5.10.0-pserver #5.10.0-1+feature+linux+next+20201214.1025+0910d71
[  778.220529] Hardware name: Supermicro Super Server/X11DDW-L, BIOS 3.3 02/21/2020
[  778.220555] Call Trace:
[  778.220609]  dump_stack+0x99/0xcb
[  778.220667]  ? rnbd_srv_sess_dev_force_close+0x38/0x60 [rnbd_server]
[  778.220715]  print_address_description.constprop.7+0x1e/0x230
[  778.220750]  ? freeze_kernel_threads+0x73/0x73
[  778.220896]  ? rnbd_srv_sess_dev_force_close+0x38/0x60 [rnbd_server]
[  778.220932]  ? rnbd_srv_sess_dev_force_close+0x38/0x60 [rnbd_server]
[  778.220994]  kasan_report.cold.9+0x37/0x7c
[  778.221066]  ? kobject_put+0x80/0x270
[  778.221102]  ? rnbd_srv_sess_dev_force_close+0x38/0x60 [rnbd_server]
[  778.221184]  rnbd_srv_sess_dev_force_close+0x38/0x60 [rnbd_server]
[  778.221240]  rnbd_srv_dev_session_force_close_store+0x6a/0xc0 [rnbd_server]
[  778.221304]  ? sysfs_file_ops+0x90/0x90
[  778.221353]  kernfs_fop_write+0x141/0x240
[  778.221451]  vfs_write+0x142/0x4d0
[  778.221553]  ksys_write+0xc0/0x160
[  778.221602]  ? __ia32_sys_read+0x50/0x50
[  778.221684]  ? lockdep_hardirqs_on_prepare+0x13d/0x210
[  778.221718]  ? syscall_enter_from_user_mode+0x1c/0x50
[  778.221821]  do_syscall_64+0x33/0x40
[  778.221862]  entry_SYSCALL_64_after_hwframe+0x44/0xa9
[  778.221896] RIP: 0033:0x7f4affdd9504
[  778.221928] Code: 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b3 0f 1f 80 00 00 00 00 48 8d 05 f9 61 0d 00 8b 00 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 41 54 49 89 d4 55 48 89 f5 53
[  778.221956] RSP: 002b:00007fffebb36b28 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[  778.222011] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f4affdd9504
[  778.222038] RDX: 0000000000000002 RSI: 00007fffebb36c50 RDI: 0000000000000003
[  778.222066] RBP: 00007fffebb36c50 R08: 0000556a151aa600 R09: 00007f4affeb1540
[  778.222094] R10: fffffffffffffc19 R11: 0000000000000246 R12: 0000556a151aa520
[  778.222121] R13: 0000000000000002 R14: 00007f4affea6760 R15: 0000000000000002

[  778.222764] Allocated by task 3212:
[  778.223285]  kasan_save_stack+0x19/0x40
[  778.223316]  __kasan_kmalloc.constprop.7+0xc1/0xd0
[  778.223347]  kmem_cache_alloc_trace+0x186/0x350
[  778.223382]  rnbd_srv_rdma_ev+0xf16/0x1690 [rnbd_server]
[  778.223422]  process_io_req+0x4d1/0x670 [rtrs_server]
[  778.223573]  __ib_process_cq+0x10a/0x350 [ib_core]
[  778.223709]  ib_cq_poll_work+0x31/0xb0 [ib_core]
[  778.223743]  process_one_work+0x521/0xa90
[  778.223773]  worker_thread+0x65/0x5b0
[  778.223802]  kthread+0x1f2/0x210
[  778.223833]  ret_from_fork+0x22/0x30

[  778.224296] Freed by task 8842:
[  778.224800]  kasan_save_stack+0x19/0x40
[  778.224829]  kasan_set_track+0x1c/0x30
[  778.224860]  kasan_set_free_info+0x1b/0x30
[  778.224889]  __kasan_slab_free+0x108/0x150
[  778.224919]  slab_free_freelist_hook+0x64/0x190
[  778.224947]  kfree+0xe2/0x650
[  778.224982]  rnbd_destroy_sess_dev+0x2fa/0x3b0 [rnbd_server]
[  778.225011]  kobject_put+0xda/0x270
[  778.225046]  rnbd_srv_sess_dev_force_close+0x30/0x60 [rnbd_server]
[  778.225081]  rnbd_srv_dev_session_force_close_store+0x6a/0xc0 [rnbd_server]
[  778.225111]  kernfs_fop_write+0x141/0x240
[  778.225140]  vfs_write+0x142/0x4d0
[  778.225169]  ksys_write+0xc0/0x160
[  778.225198]  do_syscall_64+0x33/0x40
[  778.225227]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

[  778.226506] The buggy address belongs to the object at ffff88b1d6516c00
                which belongs to the cache kmalloc-512 of size 512
[  778.227464] The buggy address is located 40 bytes inside of
                512-byte region [ffff88b1d6516c00, ffff88b1d6516e00)

The problem is in the sess_dev release function we call
rnbd_destroy_sess_dev, and could free the sess_dev already, but we still
set the keep_id in rnbd_srv_sess_dev_force_close, which lead to use
after free.

To fix it, move the keep_id before the sysfs removal, and cache the
rnbd_srv_session for lock accessing,

Fixes: 786998050c ("block/rnbd-srv: close a mapped device from server side.")
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-08 08:19:18 -07:00
Jack Wang
74acfa996b block/rnbd: Select SG_POOL for RNBD_CLIENT
lkp reboot following build error:
 drivers/block/rnbd/rnbd-clt.c: In function 'rnbd_softirq_done_fn':
>> drivers/block/rnbd/rnbd-clt.c:387:2: error: implicit declaration of function 'sg_free_table_chained' [-Werror=implicit-function-declaration]
     387 |  sg_free_table_chained(&iu->sgt, RNBD_INLINE_SG_CNT);
         |  ^~~~~~~~~~~~~~~~~~~~~

The reason is CONFIG_SG_POOL is not enabled in the config, to
avoid such failure, select SG_POOL in Kconfig for RNBD_CLIENT.

Fixes: 5a1328d0c3 ("block/rnbd-clt: Dynamically allocate sglist for rnbd_iu")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-01-08 08:19:18 -07:00
Gioh Kim
9aaf9a2aba block/rnbd-clt: Does not request pdu to rtrs-clt
Previously the rnbd client requested the rtrs to allocate rnbd_iu
just after the rtrs_iu. So the rnbd client passes the size of
rnbd_iu for rtrs_clt_open() and rtrs creates an array of
rnbd_iu and rtrs_iu.

For IO handling, rnbd_iu exists after the request because we pass
the size of rnbd_iu when setting the tag-set. Therefore we do not
use the rnbd_iu allocated by rtrs for IO handling.
We only use the rnbd_iu allocated by rtrs when doing session
initialization. Almost all rnbd_iu allocated by rtrs are wasted.

By this patch the rnbd client does not request rnbd_iu allocation
to rtrs but allocate it for itself when doing session initialization.

Also remove unused rtrs_permit_to_pdu from rtrs.

Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-16 14:56:09 -07:00
Gioh Kim
5a1328d0c3 block/rnbd-clt: Dynamically allocate sglist for rnbd_iu
The BMAX_SEGMENT static array for scatterlist is embedded in
rnbd_iu structure to avoid memory allocation in hot IO path.
In many cases, we do need only several sg entries because many IOs
have only several segments.

This patch change rnbd_iu to check the number of segments in the request
and allocate sglist dynamically.

For io path, use sg_alloc_table_chained to allocate sg list faster.

First it makes two sg entries after pdu of request.
The sg_alloc_table_chained uses the pre-allocated sg entries
if the number of segments of the request is less than two.
So it reduces the number of memory allocation.

Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-16 14:56:03 -07:00
Gioh Kim
512c781fd2 block/rnbd: Set write-back cache and fua same to the target device
The rnbd-client always sets the write-back cache and fua attributes
of the rnbd device queue regardless of the target device on the server.
That generates IO hang issue when the target device does not
support both of write-back cacne and fua.

This patch adds more fields for the cache policy and fua into the
device opening message. The rnbd-server sends the information
if the target device supports the write-back cache and fua
and rnbd-client recevives it and set the device queue accordingly.

Signed-off-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
[jwang: some minor change, rename a few varables, remove unrelated comments.]
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-16 14:55:59 -07:00
Jack Wang
3877ece01e block/rnbd: Fix typos
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-16 14:55:55 -07:00
Md Haris Iqbal
87019e7d99 block/rnbd-srv: Protect dev session sysfs removal
Since the removal of the session sysfs can also be called from the
function destroy_sess, there is a need to protect the call from the
function rnbd_srv_sess_dev_force_close

Fixes: 786998050c ("block/rnbd-srv: close a mapped device from server side.")
Signed-off-by: Md Haris Iqbal <haris.iqbal@cloud.ionos.com>
Reviewed-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-16 14:55:50 -07:00
Jack Wang
46067844ef block/rnbd-clt: Fix possible memleak
In error case, we do not free the memory for blk_symlink_name.

Do it by free the memory in error case, and set to NULL
afterwards.

Also fix the condition in rnbd_clt_remove_dev_symlink.

Fixes: 64e8a6ece1 ("block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name")
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: Md Haris Iqbal <haris.iqbal@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-16 14:55:44 -07:00
Md Haris Iqbal
e7508d4856 block/rnbd-clt: Get rid of warning regarding size argument in strlcpy
The kernel test robot triggerred the following warning,

>> drivers/block/rnbd/rnbd-clt.c:1397:42: warning: size argument in
'strlcpy' call appears to be size of the source; expected the size of the
destination [-Wstrlcpy-strlcat-size]
	strlcpy(dev->pathname, pathname, strlen(pathname) + 1);
					      ~~~~~~~^~~~~~~~~~~~~

To get rid of the above warning, use a kstrdup as Bart suggested.

Fixes: 64e8a6ece1 ("block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Md Haris Iqbal <haris.iqbal@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-16 14:55:39 -07:00
Linus Torvalds
69f637c335 for-5.11/drivers-2020-12-14
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Merge tag 'for-5.11/drivers-2020-12-14' of git://git.kernel.dk/linux-block

Pull block driver updates from Jens Axboe:
 "Nothing major in here:

   - NVMe pull request from Christoph:
        - nvmet passthrough improvements (Chaitanya Kulkarni)
        - fcloop error injection support (James Smart)
        - read-only support for zoned namespaces without Zone Append
          (Javier González)
        - improve some error message (Minwoo Im)
        - reject I/O to offline fabrics namespaces (Victor Gladkov)
        - PCI queue allocation cleanups (Niklas Schnelle)
        - remove an unused allocation in nvmet (Amit Engel)
        - a Kconfig spelling fix (Colin Ian King)
        - nvme_req_qid simplication (Baolin Wang)

   - MD pull request from Song:
        - Fix race condition in md_ioctl() (Dae R. Jeong)
        - Initialize read_slot properly for raid10 (Kevin Vigor)
        - Code cleanup (Pankaj Gupta)
        - md-cluster resync/reshape fix (Zhao Heming)

   - Move null_blk into its own directory (Damien Le Moal)

   - null_blk zone and discard improvements (Damien Le Moal)

   - bcache race fix (Dongsheng Yang)

   - Set of rnbd fixes/improvements (Gioh Kim, Guoqing Jiang, Jack Wang,
     Lutz Pogrell, Md Haris Iqbal)

   - lightnvm NULL pointer deref fix (tangzhenhao)

   - sr in_interrupt() removal (Sebastian Andrzej Siewior)

   - FC endpoint security support for s390/dasd (Jan Höppner, Sebastian
     Ott, Vineeth Vijayan). From the s390 arch guys, arch bits included
     as it made it easier for them to funnel the feature through the
     block driver tree.

   - Follow up fixes (Colin Ian King)"

* tag 'for-5.11/drivers-2020-12-14' of git://git.kernel.dk/linux-block: (64 commits)
  block: drop dead assignments in loop_init()
  sr: Remove in_interrupt() usage in sr_init_command().
  sr: Switch the sector size back to 2048 if sr_read_sector() changed it.
  cdrom: Reset sector_size back it is not 2048.
  drivers/lightnvm: fix a null-ptr-deref bug in pblk-core.c
  null_blk: Move driver into its own directory
  null_blk: Allow controlling max_hw_sectors limit
  null_blk: discard zones on reset
  null_blk: cleanup discard handling
  null_blk: Improve implicit zone close
  null_blk: improve zone locking
  block: Align max_hw_sectors to logical blocksize
  null_blk: Fail zone append to conventional zones
  null_blk: Fix zone size initialization
  bcache: fix race between setting bdev state to none and new write request direct to backing
  block/rnbd: fix a null pointer dereference on dev->blk_symlink_name
  block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name
  block/rnbd: call kobject_put in the failure path
  Documentation/ABI/rnbd-srv: add document for force_close
  block/rnbd-srv: close a mapped device from server side.
  ...
2020-12-16 13:09:32 -08:00
Colin Ian King
733c15bd3a block/rnbd: fix a null pointer dereference on dev->blk_symlink_name
Currently in the case where dev->blk_symlink_name fails to be allocates
the error return path attempts to set an end-of-string character to
the unallocated dev->blk_symlink_name causing a null pointer dereference
error. Fix this by returning with an explicity ENOMEM error (which also
is missing in the original code as was not initialized).

Fixes: 1eb54f8f5d ("block/rnbd: client: sysfs interface functions")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Addresses-Coverity: ("Dereference after null check")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-07 08:00:32 -07:00
Md Haris Iqbal
64e8a6ece1 block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name
For every rnbd_clt_dev, we alloc the pathname and blk_symlink_name
statically to NAME_MAX which is 255 bytes. In most of the cases we only
need less than 10 bytes, so 500 bytes per block device are wasted.

This commit dynamically allocates memory buffer for pathname and
blk_symlink_name.

Signed-off-by: Md Haris Iqbal <haris.iqbal@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: Lutz Pogrell <lutz.pogrell@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2020-12-04 09:41:10 -07:00