rnbd-clt: pass queue_limits to blk_mq_alloc_disk

Pass the limits rnbd-clt imposes directly to blk_mq_alloc_disk instead
of setting them one at a time.

While at it don't set an explicit number of discard segments, as 1 is
the default (which most drivers rely on).

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Link: https://lore.kernel.org/r/20240215070300.2200308-9-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: pass a queue_limits argument to blk_mq_alloc_disk

Pass a queue_limits to blk_mq_alloc_disk and apply it if non-NULL. This
will allow allocating queues with valid queue limits instead of setting
the values one at a time later.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240213073425.1621680-11-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/rnbd: use %pe to print errors

While printing error, replace %ld by %pe. %pe prints a string
whereas %ld would print an error code.

Signed-off-by: Supriti Singh <supriti.singh@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Grzegorz Prajsner <grzegorz.prajsner@ionos.com>
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Link: https://lore.kernel.org/r/20231124213422.113449-3-haris.iqbal@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/rnbd: add support for REQ_OP_WRITE_ZEROES

Remove REQ_OP_WRITE_SAME in favour of REQ_OP_WRITE_ZEROES.

Signed-off-by: Santosh Pradhan <santosh.pradhan@ionos.com>
Reviewed-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Grzegorz Prajsner <grzegorz.prajsner@ionos.com>
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Link: https://lore.kernel.org/r/20231124213422.113449-2-haris.iqbal@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: replace fmode_t with a block-specific type for block open flags

The only overlap between the block open flags mapped into the fmode_t and
other uses of fmode_t are FMODE_READ and FMODE_WRITE. Define a new
blk_mode_t instead for use in blkdev_get_by_{dev,path}, ->open and
->ioctl and stop abusing fmode_t.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd]
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/r/20230608110258.189493-28-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove the unused mode argument to ->release

The mode argument to the ->release block_device_operation is never used,
so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd]
Link: https://lore.kernel.org/r/20230608110258.189493-10-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: pass a gendisk to ->open

->open is only called on the whole device. Make that explicit by
passing a gendisk instead of the block_device.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Christian Brauner <brauner@kernel.org>
Acked-by: Jack Wang <jinpu.wang@ionos.com> [rnbd]
Link: https://lore.kernel.org/r/20230608110258.189493-9-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/rnbd-clt: fix wrong max ID in ida_alloc_max

We need to pass 'end - 1' to ida_alloc_max after switch from
ida_simple_get to ida_alloc_max.

Otherwise smatch warns.

drivers/block/rnbd/rnbd-clt.c:1460 init_dev() error: Calling ida_alloc_max() with a 'max' argument which is a power of 2. -1 missing?

Fixes: 24afc15dbe21 ("block/rnbd: Remove a useless mutex")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Link: https://lore.kernel.org/r/20221230010926.32243-1-guoqing.jiang@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/rnbd-clt: Remove the unneeded result variable

Return the value from rtrs_clt_rdma_cq_direct() directly instead of
storing it in another redundant variable.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: ye xingchen <ye.xingchen@zte.com.cn>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Link: https://lore.kernel.org/r/20220824075213.221397-1-ye.xingchen@zte.com.cn
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: Change the return type of blk_mq_map_queues() into void

Since blk_mq_map_queues() and the .map_queues() callbacks always return 0,
change their return type into void. Most callers ignore the returned value
anyway.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Doug Gilbert <dgilbert@interlog.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: John Garry <john.garry@huawei.com>
Acked-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Link: https://lore.kernel.org/r/20220815170043.19489-3-bvanassche@acm.org
[axboe: fold in fix from Bart]
Signed-off-by: Jens Axboe <axboe@kernel.dk>

rnbd-clt: make rnbd_clt_change_capacity return void

No need to checking the return value, make it return void.

Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Link: https://lore.kernel.org/r/20220706133152.12058-9-guoqing.jiang@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>

rnbd-clt: pass sector_t type for resize capacity

Let's change the parameter type to 'sector_t' then we don't need to cast
it from rnbd_clt_resize_dev_store, and update rnbd_clt_resize_disk too.

Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Link: https://lore.kernel.org/r/20220706133152.12058-8-guoqing.jiang@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>

rnbd-clt: check capacity inside rnbd_clt_change_capacity

Currently, process_msg_open_rsp checks if capacity changed or not before
call rnbd_clt_change_capacity while the checking also make sense for
rnbd_clt_resize_dev_store, let's move the checking into the function.

Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Link: https://lore.kernel.org/r/20220706133152.12058-7-guoqing.jiang@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>

rnbd-clt: reduce the size of struct rnbd_clt_dev

Previously, both map and remap trigger rnbd_clt_set_dev_attr to set
some members in rnbd_clt_dev such as wc, fua and logical_block_size
etc, but those members are only useful for map scenario given the
setup_request_queue is only called from the path:

rnbd_clt_map_device -> rnbd_client_setup_device

Since rnbd_clt_map_device frees rsp after rnbd_client_setup_device,
we can pass rsp to rnbd_client_setup_device and it's callees, which
means queue's attributes can be set directly from relevant members
of rsp instead from rnbd_clt_dev.

After that, we can kill 11 members from rnbd_clt_dev, and we don't
need rnbd_clt_set_dev_attr either.

Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Link: https://lore.kernel.org/r/20220706133152.12058-5-guoqing.jiang@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>

rnbd-clt: kill read_only from struct rnbd_clt_dev

The member is not needed since we can call get_disk_ro to achieve the
same goal.

Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Link: https://lore.kernel.org/r/20220706133152.12058-4-guoqing.jiang@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>

rnbd-clt: don't free rsp in msg_open_conf for map scenario

For map scenario, rsp is freed in two places:

1. msg_open_conf frees rsp if rtrs_clt_request returns 0.

2. Otherwise, rsp is freed by the call sites of rtrs_clt_request.

Now, We'd like to control full lifecycle of rsp in rnbd_clt_map_device,
with that, it is feasible to pass rsp to rnbd_client_setup_device in
next commit.

For 1, it is possible to free rsp from the caller of send_usr_msg
because of the synchronization of iu->comp.wait. And we put iu later
in rnbd_clt_map_device to ensure order of release rsp and iu.

Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Link: https://lore.kernel.org/r/20220706133152.12058-3-guoqing.jiang@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>

rnbd-clt: open code send_msg_open in rnbd_clt_map_device

Let's open code it in rnbd_clt_map_device, then we can use information
from rsp to setup gendisk and request_queue in next commits. After that,
we can remove some members (wc, fua and max_hw_sectors etc) from struct
rnbd_clt_dev.

Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@linux.dev>
Link: https://lore.kernel.org/r/20220706133152.12058-2-guoqing.jiang@linux.dev
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove blk_cleanup_disk

blk_cleanup_disk is nothing but a trivial wrapper for put_disk now,
so remove it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20220619060552.1850436-7-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: simplify disk shutdown

Set the queue dying flag and call blk_mq_exit_queue from del_gendisk for
all disks that do not have separately allocated queues, and thus remove
the need to call blk_cleanup_queue for them.

Rename blk_cleanup_disk to blk_mq_destroy_queue to make it clear that
this function is intended only for separately allocated blk-mq queues.

This saves an extra queue freeze for devices without a separately
allocated queue.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20220619060552.1850436-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/rnbd-clt: Avoid flush_workqueue(system_long_wq) usage

Flushing system-wide workqueues is dangerous and will be forbidden.

Replace system_long_wq with local rnbd_clt_wq.

Link: https://lkml.kernel.org/r/49925af7-78a8-a3dd-bce6-cfc02e1a9236@I-love.SAKURA.ne.jp

Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Reviewed-by: Santosh Kumar Pradhan <santosh.pradhan@ionos.com>
Link: https://lore.kernel.org/r/20220413123420.66470-1-jinpu.wang@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: decouple REQ_OP_SECURE_ERASE from REQ_OP_DISCARD

Secure erase is a very different operation from discard in that it is
a data integrity operation vs hint. Fully split the limits and helper
infrastructure to make the separation more clear.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> [drbd]
Acked-by: Ryusuke Konishi <konishi.ryusuke@gmail.com> [nifs2]
Acked-by: Jaegeuk Kim <jaegeuk@kernel.org> [f2fs]
Acked-by: Coly Li <colyli@suse.de> [bcache]
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Acked-by: Chao Yu <chao@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-27-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: remove QUEUE_FLAG_DISCARD

Just use a non-zero max_discard_sectors as an indicator for discard
support, similar to what is done for write zeroes.

The only places where needs special attention is the RAID5 driver,
which must clear discard support for security reasons by default,
even if the default stacking rules would allow for it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> [drbd]
Acked-by: Jan Höppner <hoeppner@linux.ibm.com> [s390]
Acked-by: Coly Li <colyli@suse.de> [bcache]
Acked-by: David Sterba <dsterba@suse.com> [btrfs]
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220415045258.199825-25-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

scsi: rnbd: Remove WRITE_SAME support

REQ_OP_WRITE_SAME was only ever submitted by the legacy Linux zeroing code,
which has switched to use REQ_OP_WRITE_ZEROES long before rnbd was even
merged.

Link: https://lore.kernel.org/r/20220209082828.2629273-4-hch@lst.de
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

blk-mq: prepare for implementing hctx table via xarray

It is inevitable to cause use-after-free on q->queue_hw_ctx between
queue_for_each_hw_ctx() and blk_mq_update_nr_hw_queues(). And converting
to xarray can fix the uaf, meantime code gets cleaner.

Prepare for converting q->queue_hctx_ctx into xarray, one thing is that
xa_for_each() can only accept 'unsigned long' as index, so changes type
of hctx index of queue_for_each_hw_ctx() into 'unsigned long'.

Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20220308073219.91173-6-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/rnbd: Remove a useless mutex

According to lib/idr.c,
The IDA handles its own locking. It is safe to call any of the IDA
functions without synchronisation in your code.

so the 'ida_lock' mutex can just be removed.
It is here only to protect some ida_simple_get()/ida_simple_remove() calls.

While at it, switch to ida_alloc_XXX()/ida_free() instead to
ida_simple_get()/ida_simple_remove().
The latter is deprecated and more verbose.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Link: https://lore.kernel.org/r/7f9eccd8b1fce1bac45ac9b01a78cf72f54c0a61.1644266862.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/rnbd: client device does not care queue/rotational

On client side, the device is a network device. There is no reason
to set rotational even-if the target device on server is rotational.

Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Link: https://lore.kernel.org/r/20220114155855.984144-3-haris.iqbal@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/rnbd-clt: fix CHECK:BRACES warning

This patch fix the "CHECK:BRACES: braces {} should be used on all
arms of this statement" warning from checkpatch

Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Link: https://lore.kernel.org/r/20220114155855.984144-2-haris.iqbal@ionos.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

all: replace find_next{,_zero}_bit with find_first{,_zero}_bit where appropriate

find_first{,_zero}_bit is a more effective analogue of 'next' version if
start == 0. This patch replaces 'next' with 'first' where things look
trivial.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>

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>

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>

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>

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>

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>

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>

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>

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>

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: f7a7a5c228d45 ("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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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: f7a7a5c228d4 ("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>

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: 5a1328d0c3a7 ("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>

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>

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>

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>

block/rnbd: Fix typos

Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

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: 64e8a6ece1a5 ("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>

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>

block/rnbd-clt: support mapping two devices with the same name from different servers

Previously, we can't map same device name from different sessions
due to the limitation of sysfs naming mechanism.

root@clt2:~# ls -l /sys/class/rnbd-client/ctl/devices/
total 0
lrwxrwxrwx 1 root 0 Sep 2 16:31 !dev!nullb1 -> ../../../block/rnbd0

We only use the device name in above, which caused device with
the same name can't be mapped from another server. To address
the issue, the sessname is appended to the node to differentiate
where the device comes from.

Also, we need to check if the pathname is existed in a specific
session instead of search it in global sess_list.

Signed-off-by: Guoqing Jiang <guoqing.jiang@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: Md Haris Iqbal <haris.iqbal@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/rnbd-clt: Make path parameter optional for map_device

During map_device if the given session exists, then the path parameter is
not used. In such a case, the path parameter is redundant.

This commit makes the path parameter optional for map_device. When the
path parameter is not given, if the session exists then that is used to
establish the rtrs connection.

If the session does not exist, and the path parameter is also missing,
then map_device fails.

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>

rnbd: use set_capacity_and_notify

Use set_capacity_and_notify to set the size of both the disk and block
device. This also gets the uevent notifications for the resize for free.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/rnbd-clt: send_msg_close if any error occurs after send_msg_open

After send_msg_open is done, send_msg_close should be done
if any error occurs and it is necessary to recover
what has been done.

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>

block/rnbd-clt: do not cap max_hw_sectors & max_segments with remote device

The max_hw_secotrs is only limited by the transport, not remote device,
block layer on server side will split to the device limit if it's too
big.

The max_segments, similar, and rtrs server will submit single buffer, so
no need to cap.

Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/rnbd-clt: remove nr argument from send_usr_msg

The argument is not needed since all callers pass 1 for it.

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>

blk-mq: Rename BLK_MQ_F_TAG_SHARED as BLK_MQ_F_TAG_QUEUE_SHARED

BLK_MQ_F_TAG_SHARED actually means that tags is shared among request
queues, all of which should belong to LUNs attached to same HBA.

So rename it to make the point explicitly.

[jpg: rebase a few times, add rnbd-clt.c change]

Suggested-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Tested-by: Douglas Gilbert <dgilbert@interlog.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block: add a new revalidate_disk_size helper

revalidate_disk is a relative awkward helper for driver use, as it first
calls an optional driver method and then updates the block device size,
while most callers either don't need the method call at all, or want to
keep state between the caller and the called method.

Add a revalidate_disk_size helper that just performs the update of the
block device size from the gendisk one, and switch all drivers that do
not implement ->revalidate_disk to use the new helper instead of
revalidate_disk()

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/rnbd: Fix an IS_ERR() vs NULL check in find_or_create_sess()

The alloc_sess() function returns error pointers, it never returns NULL.

Fixes: f7a7a5c228d4 ("block/rnbd: client: main functionality")
Link: https://lore.kernel.org/r/20200519120347.GD42765@mwanda
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

rnbd/rtrs: Pass max segment size from blk user to the rdma library

When Block Device Layer is disabled, BLK_MAX_SEGMENT_SIZE is undefined.
The rtrs is a transport library and should compile independently of the
block layer. The desired max segment size should be passed down by the
user.

Introduce max_segment_size parameter for the rtrs_clt_open() call.

Fixes: f7a7a5c228d4 ("block/rnbd: client: main functionality")
Fixes: 6a98d71daea1 ("RDMA/rtrs: client: main functionality")
Fixes: cb80329c9434 ("RDMA/rtrs: client: private header with client structs and functions")
Fixes: b5c27cdb094e ("RDMA/rtrs: public interface header to establish RDMA connections")
Link: https://lore.kernel.org/r/20200519111419.924170-1-danil.kipnis@cloud.ionos.com
Signed-off-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

block/rnbd: client: main functionality

This is main functionality of rnbd-client module, which provides interface
to map remote device as local block device /dev/rnbd<N> and feeds RTRS
with IO requests.

Link: https://lore.kernel.org/r/20200511135131.27580-18-danil.kipnis@cloud.ionos.com
Signed-off-by: Danil Kipnis <danil.kipnis@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>