In case p2p device was found but the p2p pool is empty, the nvme target
is still trying to free the sgl from the p2p pool instead of the
regular sgl pool and causing a crash (BUG() is called). Instead, assign
the p2p_dev for the request only if it was allocated from p2p pool.

This is the crash that was caused:

[Sun May 30 19:13:53 2021] ------------[ cut here ]------------
[Sun May 30 19:13:53 2021] kernel BUG at lib/genalloc.c:518!
[Sun May 30 19:13:53 2021] invalid opcode: 0000 [#1] SMP PTI
...
[Sun May 30 19:13:53 2021] kernel BUG at lib/genalloc.c:518!
...
[Sun May 30 19:13:53 2021] RIP: 0010:gen_pool_free_owner+0xa8/0xb0
...
[Sun May 30 19:13:53 2021] Call Trace:
[Sun May 30 19:13:53 2021] ------------[ cut here ]------------
[Sun May 30 19:13:53 2021]  pci_free_p2pmem+0x2b/0x70
[Sun May 30 19:13:53 2021]  pci_p2pmem_free_sgl+0x4f/0x80
[Sun May 30 19:13:53 2021]  nvmet_req_free_sgls+0x1e/0x80 [nvmet]
[Sun May 30 19:13:53 2021] kernel BUG at lib/genalloc.c:518!
[Sun May 30 19:13:53 2021]  nvmet_rdma_release_rsp+0x4e/0x1f0 [nvmet_rdma]
[Sun May 30 19:13:53 2021]  nvmet_rdma_send_done+0x1c/0x60 [nvmet_rdma]

Fixes: c6e3f133

 ("nvmet: add metadata support for block devices")
Reviewed-by: Israel Rukshin <israelr@nvidia.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

During concurrent reset and delete calls the reset workqueue is
flushed, causing nvme_loop_reset_ctrl_work() to be executed when
the controller is in state DELETING or DELETING_NOIO.
But this is expected, so we shouldn't issue a WARN_ON here.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

We need to check the NVME_LOOP_Q_LIVE flag in
nvme_loop_destroy_admin_queue() to protect against duplicate
invocations eg during concurrent reset and remove calls.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

When the call to nvme_enable_ctrl() in nvme_loop_configure_admin_queue()
fails the NVME_LOOP_Q_LIVE flag is not cleared.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

The queue count is increased in nvme_loop_init_io_queues(), so we
need to reset it to 1 at the end of nvme_loop_destroy_io_queues().
Otherwise the function is not re-entrant safe, and crash will happen
during concurrent reset and remove calls.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

We have only 2 inline sg entries and we allow 4 sg entries for the send
wr sge. Larger sgls entries will be chained. However when we build
in-capsule send wr sge, we iterate without taking into account that the
sgl may be chained and still fit in-capsule (which can happen if the sgl
is bigger than 2, but lower-equal to 4).

Fix in-capsule data mapping to correctly iterate chained sgls.

Fixes: 38e18002

 ("nvme-rdma: Avoid preallocating big SGL for data")
Reported-by: Walker, Benjamin <benjamin.walker@intel.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Pull NVMe fixes from Christoph:

"nvme fixes for Linux 5.13

 - fix a memory leak in nvme_cdev_add (Guoqing Jiang)
 - fix inline data size comparison in nvmet_tcp_queue_response (Hou Pu)
 - fix false keep-alive timeout when a controller is torn down
   (Sagi Grimberg)
 - fix a nvme-tcp Kconfig dependency (Sagi Grimberg)
 - short-circuit reconnect retries for FC (Hannes Reinecke)
 - decode host pathing error for connect (Hannes Reinecke)"

* tag 'nvme-5.13-2021-05-27' of git://git.infradead.org/nvme:
  nvmet: fix false keep-alive timeout when a controller is torn down
  nvmet-tcp: fix inline data size comparison in nvmet_tcp_queue_response
  nvme-tcp: remove incorrect Kconfig dep in BLK_DEV_NVME
  nvme-fabrics: decode host pathing error for connect
  nvme-fc: short-circuit reconnect retries
  nvme: fix potential memory leaks in nvme_cdev_add

Pull MD fix from Song.

* 'md-fixes' of https://git.kernel.org/pub/scm/linux/kernel/git/song/md:
  md/raid5: remove an incorrect assert in in_chunk_boundary

Controller teardown flow may take some time in case it has many I/O
queues, and the host may not send us keep-alive during this period.
Hence reset the traffic based keep-alive timer so we don't trigger
a controller teardown as a result of a keep-alive expiration.

Reported-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Using "<=" instead "<" to compare inline data size.

Fixes: bdaf1327

 ("nvmet-tcp: fix a segmentation fault during io parsing error")
Signed-off-by: Hou Pu <houpu.main@gmail.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

We need to select NVME_CORE.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Now that the original bdev is stored in the bio this assert is incorrect
and will trigger for any partitioned raid5 device.

Reported-by: Florian Dazinger <spam02@dazinger.net>
Tested-by: Florian Dazinger <spam02@dazinger.net>
Cc: stable@vger.kernel.org # 5.12
Fixes: 309dca30

 ("block: store a block_device pointer in struct bio"),
Reviewed-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>

Fix crash with illegal operation exception in dasd_device_tasklet.
Commit b7294932 ("s390/dasd: Prepare for additional path event handling")
renamed the verify_path function for ECKD but not for FBA and DIAG.
This leads to a panic when the path verification function is called for a
FBA or DIAG device.

Fix by defining a wrapper function for dasd_generic_verify_path().

Fixes: b7294932

 ("s390/dasd: Prepare for additional path event handling")
Cc: <stable@vger.kernel.org> #5.11
Reviewed-by: Jan Hoeppner <hoeppner@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/20210525125006.157531-2-sth@linux.ibm.com


Signed-off-by: Jens Axboe <axboe@kernel.dk>

Add an additional decoding for 'host pathing error' during connect.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Returning an nvme status from nvme_fc_create_association() indicates
that the association is established, and we should honour the DNR bit.
If it's set a reconnect attempt will just return the same error, so
we can short-circuit the reconnect attempts and fail the connection
directly.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Reviewed-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

We need to call put_device if cdev_device_add failed, otherwise
kmemleak has below report.

[<0000000024c71758>] kmem_cache_alloc_trace+0x233/0x480
[<00000000ad2813ed>] device_add+0x7ff/0xe10
[<0000000035bc54c4>] cdev_device_add+0x72/0xa0
[<000000006c9aa1e8>] nvme_cdev_add+0xa9/0xf0 [nvme_core]
[<000000003c4d492d>] nvme_mpath_set_live+0x251/0x290 [nvme_core]
[<00000000889a58da>] nvme_mpath_add_disk+0x268/0x320 [nvme_core]
[<00000000192e7161>] nvme_alloc_ns+0x669/0xac0 [nvme_core]
[<000000007a1a6041>] nvme_validate_or_alloc_ns+0x156/0x280 [nvme_core]
[<000000003a763c35>] nvme_scan_work+0x221/0x3c0 [nvme_core]
[<000000009ff10706>] process_one_work+0x5cf/0xb10
[<000000000644ee25>] worker_thread+0x7a/0x680
[<00000000285ebd2f>] kthread+0x1c6/0x210
[<00000000e297c6ea>] ret_from_fork+0x22/0x30

Fixes: 2637baed

 ("nvme: introduce generic per-namespace chardev")
Signed-off-by: Guoqing Jiang <jiangguoqing@kylinos.cn>
Reviewed-by: Javier González <javier.gonz@samsung.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

When BLKRRPART is called concurrently with del_gendisk, the partitions
rescan can create a stale partition that will never be be cleaned up.

Fix this by checking the the disk is up before rescanning partitions
while under bd_mutex.

Signed-off-by: Gulam Mohamed <gulam.mohamed@oracle.com>
[hch: split from a larger patch]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20210514131842.1600568-3-hch@lst.de


Signed-off-by: Jens Axboe <axboe@kernel.dk>

As an artifact of how gendisk lookup used to work in earlier kernels,
GENHD_FL_UP is only cleared very late in del_gendisk, and a global lock
is used to prevent opens from succeeding while del_gendisk is tearing
down the gendisk.  Switch to clearing the flag early and under bd_mutex
so that callers can use bd_mutex to stabilize the flag, which removes
the need for the global mutex.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20210514131842.1600568-2-hch@lst.de


Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull NVMe fixes from Christoph:

"nvme fixes for Linux 5.13:

 - nvme-tcp corruption and timeout fixes (Sagi Grimberg, Keith Busch)
 - nvme-fc teardown fix (James Smart)
 - nvmet/nvme-loop memory leak fixes (Wu Bo)"

* tag 'nvme-5.13-2021-05-20' of git://git.infradead.org/nvme:
  nvme-fc: clear q_live at beginning of association teardown
  nvme-tcp: rerun io_work if req_list is not empty
  nvme-tcp: fix possible use-after-completion
  nvme-loop: fix memory leak in nvme_loop_create_ctrl()
  nvmet: fix memory leak in nvmet_alloc_ctrl()

The __nvmf_check_ready() routine used to bounce all filesystem io if the
controller state isn't LIVE.  However, a later patch changed the logic so
that it rejection ends up being based on the Q live check.  The FC
transport has a slightly different sequence from rdma and tcp for
shutting down queues/marking them non-live.  FC marks its queue non-live
after aborting all ios and waiting for their termination, leaving a
rather large window for filesystem io to continue to hit the transport.
Unfortunately this resulted in filesystem I/O or applications seeing I/O
errors.

Change the FC transport to mark the queues non-live at the first sign of
teardown for the association (when I/O is initially terminated).

Fixes: 73a53799

 ("nvme-fabrics: allow to queue requests for live queues")
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

A possible race condition exists where the request to send data is
enqueued from nvme_tcp_handle_r2t()'s will not be observed by
nvme_tcp_send_all() if it happens to be running. The driver relies on
io_work to send the enqueued request when it is runs again, but the
concurrently running nvme_tcp_send_all() may not have released the
send_mutex at that time. If no future commands are enqueued to re-kick
the io_work, the request will timeout in the SEND_H2C state, resulting
in a timeout error like:

  nvme nvme0: queue 1: timeout request 0x3 type 6

Ensure the io_work continues to run as long as the req_list is not empty.

Fixes: db5ad6b7

 ("nvme-tcp: try to send request in queue_rq context")
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Commit db5ad6b7

 ("nvme-tcp: try to send request in queue_rq
context") added a second context that may perform a network send.
This means that now RX and TX are not serialized in nvme_tcp_io_work
and can run concurrently.

While there is correct mutual exclusion in the TX path (where
the send_mutex protect the queue socket send activity) RX activity,
and more specifically request completion may run concurrently.

This means we must guarantee that any mutation of the request state
related to its lifetime, bytes sent must not be accessed when a completion
may have possibly arrived back (and processed).

The race may trigger when a request completion arrives, processed
_and_ reused as a fresh new request, exactly in the (relatively short)
window between the last data payload sent and before the request iov_iter
is advanced.

Consider the following race:
1. 16K write request is queued
2. The nvme command and the data is sent to the controller (in-capsule
   or solicited by r2t)
3. After the last payload is sent but before the req.iter is advanced,
   the controller sends back a completion.
4. The completion is processed, the request is completed, and reused
   to transfer a new request (write or read)
5. The new request is queued, and the driver reset the request parameters
   (nvme_tcp_setup_cmd_pdu).
6. Now context in (2) resumes execution and advances the req.iter

==> use-after-completion as this is already a new request.

Fix this by making sure the request is not advanced after the last
data payload send, knowing that a completion may have arrived already.

An alternative solution would have been to delay the request completion
or state change waiting for reference counting on the TX path, but besides
adding atomic operations to the hot-path, it may present challenges in
multi-stage R2T scenarios where a r2t handler needs to be deferred to
an async execution.

Reported-by: Narayan Ayalasomayajula <narayan.ayalasomayajula@wdc.com>
Tested-by: Anil Mishra <anil.mishra@wdc.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Cc: stable@vger.kernel.org # v5.8+
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

When creating loop ctrl in nvme_loop_create_ctrl(), if nvme_init_ctrl()
fails, the loop ctrl should be freed before jumping to the "out" label.

Fixes: 3a85a5de

 ("nvme-loop: add a NVMe loopback host driver")
Signed-off-by: Wu Bo <wubo40@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

When creating ctrl in nvmet_alloc_ctrl(), if the cntlid_min is larger
than cntlid_max of the subsystem, and jumps to the
"out_free_changed_ns_list" label, but the ctrl->sqs lack of be freed.
Fix this by jumping to the "out_free_sqs" label.

Fixes: 94a39d61

 ("nvmet: make ctrl-id configurable")
Signed-off-by: Wu Bo <wubo40@huawei.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Fix the following kernel-doc warning:

block/partitions/efi.c:685: warning: wrong kernel-doc identifier on line:
 * efi_partition(struct parsed_partitions *state)

Cc: Alexander Viro <viro@math.psu.edu>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20210513171708.8391-1-bvanassche@acm.org


Signed-off-by: Jens Axboe <axboe@kernel.dk>

If a tag set is shared across request queues (e.g. SCSI LUNs) then the
block layer core keeps track of the number of active request queues in
tags->active_queues. blk_mq_tag_busy() and blk_mq_tag_idle() update that
atomic counter if the hctx flag BLK_MQ_F_TAG_QUEUE_SHARED is set. Make
sure that blk_mq_exit_queue() calls blk_mq_tag_idle() before that flag is
cleared by blk_mq_del_queue_tag_set().

Cc: Christoph Hellwig <hch@infradead.org>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.com>
Fixes: 0d2602ca

 ("blk-mq: improve support for shared tags maps")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20210513171529.7977-1-bvanassche@acm.org


Signed-off-by: Jens Axboe <axboe@kernel.dk>

In case of shared sbitmap, request won't be held in plug list any more
sine commit 32bc15af ("blk-mq: Facilitate a shared sbitmap per
tagset"), this way makes request merge from flush plug list & batching
submission not possible, so cause performance regression.

Yanhui reports performance regression when running sequential IO
test(libaio, 16 jobs, 8 depth for each job) in VM, and the VM disk
is emulated with image stored on xfs/megaraid_sas.

Fix the issue by recovering original behavior to allow to hold request
in plug list.

Cc: Yanhui Ma <yama@redhat.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: kashyap.desai@broadcom.com
Fixes: 32bc15af

 ("blk-mq: Facilitate a shared sbitmap per tagset")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20210514022052.1047665-1-ming.lei@redhat.com


Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull NVMe fixes from Christoph:

"nvme fix for Linux 5.13

 - correct the check for using the inline bio in nvmet
   (Chaitanya Kulkarni)
 - demote unsupported command warnings (Chaitanya Kulkarni)
 - fix corruption due to double initializing ANA state (me, Hou Pu)
 - reset ns->file when open fails (Daniel Wagner)
 - fix a NULL deref when SEND is completed with error in nvmet-rdma
   (Michal Kalderon)"

* tag 'nvme-5.13-2021-05-13' of git://git.infradead.org/nvme:
  nvmet: use new ana_log_size instead the old one
  nvmet: seset ns->file when open fails
  nvmet: demote fabrics cmd parse err msg to debug
  nvmet: use helper to remove the duplicate code
  nvmet: demote discovery cmd parse err msg to debug
  nvmet-rdma: Fix NULL deref when SEND is completed with error
  nvmet: fix inline bio check for passthru
  nvmet: fix inline bio check for bdev-ns
  nvme-multipath: fix double initialization of ANA state

The new ana_log_size should be used instead of the old one.
Or kernel NULL pointer dereference will happen like below:

[   38.957849][   T69] BUG: kernel NULL pointer dereference, address: 000000000000003c
[   38.975550][   T69] #PF: supervisor write access in kernel mode
[   38.975955][   T69] #PF: error_code(0x0002) - not-present page
[   38.976905][   T69] PGD 0 P4D 0
[   38.979388][   T69] Oops: 0002 [#1] SMP NOPTI
[   38.980488][   T69] CPU: 0 PID: 69 Comm: kworker/0:2 Not tainted 5.12.0+ #54
[   38.981254][   T69] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[   38.982502][   T69] Workqueue: events nvme_loop_execute_work
[   38.985219][   T69] RIP: 0010:memcpy_orig+0x68/0x10f
[   38.986203][   T69] Code: 83 c2 20 eb 44 48 01 d6 48 01 d7 48 83 ea 20 0f 1f 00 48 83 ea 20 4c 8b 46 f8 4c 8b 4e f0 4c 8b 56 e8 4c 8b 5e e0 48 8d 76 e0 <4c> 89 47 f8 4c 89 4f f0 4c 89 57 e8 4c 89 5f e0 48 8d 7f e0 73 d2
[   38.987677][   T69] RSP: 0018:ffffc900001b7d48 EFLAGS: 00000287
[   38.987996][   T69] RAX: 0000000000000020 RBX: 0000000000000024 RCX: 0000000000000010
[   38.988327][   T69] RDX: ffffffffffffffe4 RSI: ffff8881084bc004 RDI: 0000000000000044
[   38.988620][   T69] RBP: 0000000000000024 R08: 0000000100000000 R09: 0000000000000000
[   38.988991][   T69] R10: 0000000100000000 R11: 0000000000000001 R12: 0000000000000024
[   38.989289][   T69] R13: ffff8881084bc000 R14: 0000000000000000 R15: 0000000000000024
[   38.989845][   T69] FS:  0000000000000000(0000) GS:ffff888237c00000(0000) knlGS:0000000000000000
[   38.990234][   T69] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   38.990490][   T69] CR2: 000000000000003c CR3: 00000001085b2000 CR4: 00000000000006f0
[   38.991105][   T69] Call Trace:
[   38.994157][   T69]  sg_copy_buffer+0xb8/0xf0
[   38.995357][   T69]  nvmet_copy_to_sgl+0x48/0x6d
[   38.995565][   T69]  nvmet_execute_get_log_page_ana+0xd4/0x1cb
[   38.995792][   T69]  nvmet_execute_get_log_page+0xc9/0x146
[   38.995992][   T69]  nvme_loop_execute_work+0x3e/0x44
[   38.996181][   T69]  process_one_work+0x1c3/0x3c0
[   38.996393][   T69]  worker_thread+0x44/0x3d0
[   38.996600][   T69]  ? cancel_delayed_work+0x90/0x90
[   38.996804][   T69]  kthread+0xf7/0x130
[   38.996961][   T69]  ? kthread_create_worker_on_cpu+0x70/0x70
[   38.997171][   T69]  ret_from_fork+0x22/0x30
[   38.997705][   T69] Modules linked in:
[   38.998741][   T69] CR2: 000000000000003c
[   39.000104][   T69] ---[ end trace e719927b609d0fa0 ]---

Fixes: 5e1f6899

 ("nvme-multipath: fix double initialization of ANA state")
Signed-off-by: Hou Pu <houpu.main@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Reset the ns->file value to NULL also in the error case in
nvmet_file_ns_enable().

The ns->file variable points either to file object or contains the
error code after the filp_open() call. This can lead to following
problem:

When the user first setups an invalid file backend and tries to enable
the ns, it will fail. Then the user switches over to a bdev backend
and enables successfully the ns. The first received I/O will crash the
system because the IO backend is chosen based on the ns->file value:

static u16 nvmet_parse_io_cmd(struct nvmet_req *req)
{
	[...]

	if (req->ns->file)
		return nvmet_file_parse_io_cmd(req);

	return nvmet_bdev_parse_io_cmd(req);
}

Reported-by: Enzo Matsumiya <ematsumiya@suse.com>
Signed-off-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Replace the following two statements by the statement “goto put_nbd;”

	nbd_put(nbd);
	return 0;

Signed-off-by: Sun Ke <sunke32@huawei.com>
Suggested-by: Markus Elfring <Markus.Elfring@web.de>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/20210512114331.1233964-3-sunke32@huawei.com


Signed-off-by: Jens Axboe <axboe@kernel.dk>

Open /dev/nbdX first, the config_refs will be 1 and
the pointers in nbd_device are still null. Disconnect
/dev/nbdX, then reference a null recv_workq. The
protection by config_refs in nbd_genl_disconnect is useless.

[  656.366194] BUG: kernel NULL pointer dereference, address: 0000000000000020
[  656.368943] #PF: supervisor write access in kernel mode
[  656.369844] #PF: error_code(0x0002) - not-present page
[  656.370717] PGD 10cc87067 P4D 10cc87067 PUD 1074b4067 PMD 0
[  656.371693] Oops: 0002 [#1] SMP
[  656.372242] CPU: 5 PID: 7977 Comm: nbd-client Not tainted 5.11.0-rc5-00040-g76c057c84d28 #1
[  656.373661] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014
[  656.375904] RIP: 0010:mutex_lock+0x29/0x60
[  656.376627] Code: 00 0f 1f 44 00 00 55 48 89 fd 48 83 05 6f d7 fe 08 01 e8 7a c3 ff ff 48 83 05 6a d7 fe 08 01 31 c0 65 48 8b 14 25 00 6d 01 00 <f0> 48 0f b1 55 d
[  656.378934] RSP: 0018:ffffc900005eb9b0 EFLAGS: 00010246
[  656.379350] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[  656.379915] RDX: ffff888104cf2600 RSI: ffffffffaae8f452 RDI: 0000000000000020
[  656.380473] RBP: 0000000000000020 R08: 0000000000000000 R09: ffff88813bd6b318
[  656.381039] R10: 00000000000000c7 R11: fefefefefefefeff R12: ffff888102710b40
[  656.381599] R13: ffffc900005eb9e0 R14: ffffffffb2930680 R15: ffff88810770ef00
[  656.382166] FS:  00007fdf117ebb40(0000) GS:ffff88813bd40000(0000) knlGS:0000000000000000
[  656.382806] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  656.383261] CR2: 0000000000000020 CR3: 0000000100c84000 CR4: 00000000000006e0
[  656.383819] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  656.384370] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  656.384927] Call Trace:
[  656.385111]  flush_workqueue+0x92/0x6c0
[  656.385395]  nbd_disconnect_and_put+0x81/0xd0
[  656.385716]  nbd_genl_disconnect+0x125/0x2a0
[  656.386034]  genl_family_rcv_msg_doit.isra.0+0x102/0x1b0
[  656.386422]  genl_rcv_msg+0xfc/0x2b0
[  656.386685]  ? nbd_ioctl+0x490/0x490
[  656.386954]  ? genl_family_rcv_msg_doit.isra.0+0x1b0/0x1b0
[  656.387354]  netlink_rcv_skb+0x62/0x180
[  656.387638]  genl_rcv+0x34/0x60
[  656.387874]  netlink_unicast+0x26d/0x590
[  656.388162]  netlink_sendmsg+0x398/0x6c0
[  656.388451]  ? netlink_rcv_skb+0x180/0x180
[  656.388750]  ____sys_sendmsg+0x1da/0x320
[  656.389038]  ? ____sys_recvmsg+0x130/0x220
[  656.389334]  ___sys_sendmsg+0x8e/0xf0
[  656.389605]  ? ___sys_recvmsg+0xa2/0xf0
[  656.389889]  ? handle_mm_fault+0x1671/0x21d0
[  656.390201]  __sys_sendmsg+0x6d/0xe0
[  656.390464]  __x64_sys_sendmsg+0x23/0x30
[  656.390751]  do_syscall_64+0x45/0x70
[  656.391017]  entry_SYSCALL_64_after_hwframe+0x44/0xa9

To fix it, just add if (nbd->recv_workq) to nbd_disconnect_and_put().

Fixes: e9e006f5

 ("nbd: fix max number of supported devs")
Signed-off-by: Sun Ke <sunke32@huawei.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/20210512114331.1233964-2-sunke32@huawei.com


Signed-off-by: Jens Axboe <axboe@kernel.dk>

Last users of blk_account_rq gone with patch commit a1ce35fa


("block: remove dead elevator code") and now it gets no caller, it can
be safely removed.

Signed-off-by: Lin Feng <linf@wangsu.com>
Link: https://lore.kernel.org/r/20210512100124.173769-1-linf@wangsu.com


Signed-off-by: Jens Axboe <axboe@kernel.dk>

BFQ may merge a new bfq_queue, stably, with the last bfq_queue
created. In particular, BFQ first waits a little bit for some I/O to
flow inside the new queue, say Q2, if this is needed to understand
whether it is better or worse to merge Q2 with the last queue created,
say Q1. This delayed stable merge is performed by assigning
bic->stable_merge_bfqq = Q1, for the bic associated with Q1.

Yet, while waiting for some I/O to flow in Q2, a non-stable queue
merge of Q2 with Q1 may happen, causing the bic previously associated
with Q2 to be associated with exactly Q1 (bic->bfqq = Q1). After that,
Q2 and Q1 may happen to be split, and, in the split, Q1 may happen to
be recycled as a non-shared bfq_queue. In that case, Q1 may then
happen to undergo a stable merge with the bfq_queue pointed by
bic->stable_merge_bfqq. Yet bic->stable_merge_bfqq still points to
Q1. So Q1 would be merged with itself.

This commit fixes this error by intercepting this situation, and
canceling the schedule of the stable merge.

Fixes: 430a67f9

 ("block, bfq: merge bursts of newly-created queues")
Signed-off-by: Pietro Pedroni <pedroni.pietro.96@gmail.com>
Signed-off-by: Paolo Valente <paolo.valente@linaro.org>
Link: https://lore.kernel.org/r/20210512094352.85545-2-paolo.valente@linaro.org


Signed-off-by: Jens Axboe <axboe@kernel.dk>

When the weight of an active iocg is updated, weight_updated() is called
which in turn calls __propagate_weights() to update the active and inuse
weights so that the effective hierarchical weights are update accordingly.

The current implementation is incorrect for inner active nodes. For an
active leaf iocg, inuse can be any value between 1 and active and the
difference represents how much the iocg is donating. When weight is updated,
as long as inuse is clamped between 1 and the new weight, we're alright and
this is what __propagate_weights() currently implements.

However, that's not how an active inner node's inuse is set. An inner node's
inuse is solely determined by the ratio between the sums of inuse's and
active's of its children - ie. they're results of propagating the leaves'
active and inuse weights upwards. __propagate_weights() incorrectly applies
the same clamping as for a leaf when an active inner node's weight is
updated. Consider a hierarchy which looks like the following with saturating
workloads in AA and BB.

     R
   /   \
  A     B
  |     |
 AA     BB

1. For both A and B, active=100, inuse=100, hwa=0.5, hwi=0.5.

2. echo 200 > A/io.weight

3. __propagate_weights() update A's active to 200 and leave inuse at 100 as
   it's already between 1 and the new active, making A:active=200,
   A:inuse=100. As R's active_sum is updated along with A's active,
   A:hwa=2/3, B:hwa=1/3. However, because the inuses didn't change, the
   hwi's remain unchanged at 0.5.

4. The weight of A is now twice that of B but AA and BB still have the same
   hwi of 0.5 and thus are doing the same amount of IOs.

Fix it by making __propgate_weights() always calculate the inuse of an
active inner iocg based on the ratio of child_inuse_sum to child_active_sum.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Dan Schatzberg <dschatzberg@fb.com>
Fixes: 7caa4715 ("blkcg: implement blk-iocost")
Cc: stable@vger.kernel.org # v5.4+
Link: https://lore.kernel.org/r/YJsxnLZV1MnBcqjj@slm.duckdns.org


Signed-off-by: Jens Axboe <axboe@kernel.dk>

Host can send invalid commands and flood the target with error messages.
Demote the error message from pr_err() to pr_debug() in
nvmet_parse_fabrics_cmd() and nvmet_parse_connect_cmd().

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Use the helper nvmet_report_invalid_opcode() to report invalid opcode
so we can remove the duplicate code.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Host can send invalid commands and flood the target with error messages
for the discovery controller. Demote the error message from pr_err() to
pr_debug( in nvmet_parse_discovery_cmd(). 

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

When running some traffic and taking down the link on peer, a
retry counter exceeded error is received. This leads to
nvmet_rdma_error_comp which tried accessing the cq_context to
obtain the queue. The cq_context is no longer valid after the
fix to use shared CQ mechanism and should be obtained similar
to how it is obtained in other functions from the wc->qp.

[ 905.786331] nvmet_rdma: SEND for CQE 0x00000000e3337f90 failed with status transport retry counter exceeded (12).
[ 905.832048] BUG: unable to handle kernel NULL pointer dereference at 0000000000000048
[ 905.839919] PGD 0 P4D 0
[ 905.842464] Oops: 0000 1 SMP NOPTI
[ 905.846144] CPU: 13 PID: 1557 Comm: kworker/13:1H Kdump: loaded Tainted: G OE --------- - - 4.18.0-304.el8.x86_64 #1
[ 905.872135] RIP: 0010:nvmet_rdma_error_comp+0x5/0x1b [nvmet_rdma]
[ 905.878259] Code: 19 4f c0 e8 89 b3 a5 f6 e9 5b e0 ff ff 0f b7 75 14 4c 89 ea 48 c7 c7 08 1a 4f c0 e8 71 b3 a5 f6 e9 4b e0 ff ff 0f 1f 44 00 00 <48> 8b 47 48 48 85 c0 74 08 48 89 c7 e9 98 bf 49 00 e9 c3 e3 ff ff
[ 905.897135] RSP: 0018:ffffab601c45fe28 EFLAGS: 00010246
[ 905.902387] RAX: 0000000000000065 RBX: ffff9e729ea2f800 RCX: 0000000000000000
[ 905.909558] RDX: 0000000000000000 RSI: ffff9e72df9567c8 RDI: 0000000000000000
[ 905.916731] RBP: ffff9e729ea2b400 R08: 000000000000074d R09: 0000000000000074
[ 905.923903] R10: 0000000000000000 R11: ffffab601c45fcc0 R12: 0000000000000010
[ 905.931074] R13: 0000000000000000 R14: 0000000000000010 R15: ffff9e729ea2f400
[ 905.938247] FS: 0000000000000000(0000) GS:ffff9e72df940000(0000) knlGS:0000000000000000
[ 905.938249] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 905.950067] nvmet_rdma: SEND for CQE 0x00000000c7356cca failed with status transport retry counter exceeded (12).
[ 905.961855] CR2: 0000000000000048 CR3: 000000678d010004 CR4: 00000000007706e0
[ 905.961855] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 905.961856] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 905.961857] PKRU: 55555554
[ 906.010315] Call Trace:
[ 906.012778] __ib_process_cq+0x89/0x170 [ib_core]
[ 906.017509] ib_cq_poll_work+0x26/0x80 [ib_core]
[ 906.022152] process_one_work+0x1a7/0x360
[ 906.026182] ? create_worker+0x1a0/0x1a0
[ 906.030123] worker_thread+0x30/0x390
[ 906.033802] ? create_worker+0x1a0/0x1a0
[ 906.037744] kthread+0x116/0x130
[ 906.040988] ? kthread_flush_work_fn+0x10/0x10
[ 906.045456] ret_from_fork+0x1f/0x40

Fixes: ca0f1a80

 ("nvmet-rdma: use new shared CQ mechanism")
Signed-off-by: Shai Malin <smalin@marvell.com>
Signed-off-by: Michal Kalderon <michal.kalderon@marvell.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

When handling passthru commands, for inline bio allocation we only
consider the transfer size. This works well when req->sg_cnt fits into
the req->inline_bvec, but it will result in the early return from
bio_add_hw_page() when req->sg_cnt > NVMET_MAX_INLINE_BVEC.

Consider an I/O of size 32768 and first buffer is not aligned to the
page boundary, then I/O is split in following manner :-

[ 2206.256140] nvmet: sg->length 3440 sg->offset 656
[ 2206.256144] nvmet: sg->length 4096 sg->offset 0
[ 2206.256148] nvmet: sg->length 4096 sg->offset 0
[ 2206.256152] nvmet: sg->length 4096 sg->offset 0
[ 2206.256155] nvmet: sg->length 4096 sg->offset 0
[ 2206.256159] nvmet: sg->length 4096 sg->offset 0
[ 2206.256163] nvmet: sg->length 4096 sg->offset 0
[ 2206.256166] nvmet: sg->length 4096 sg->offset 0
[ 2206.256170] nvmet: sg->length 656 sg->offset 0

Now the req->transfer_size == NVMET_MAX_INLINE_DATA_LEN i.e. 32768, but
the req->sg_cnt is (9) > NVMET_MAX_INLINE_BIOVEC which is (8).
This will result in early return in the following code path :-

nvmet_bdev_execute_rw()
	bio_add_pc_page()
		bio_add_hw_page()
			if (bio_full(bio, len))
				return 0;

Use previously introduced helper nvmet_use_inline_bvec() to consider
req->sg_cnt when using inline bio. This only affects nvme-loop
transport.

Fixes: dab3902b

 ("nvmet: use inline bio for passthru fast path")
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>