Commit Graph

1555 Commits

Author SHA1 Message Date
Linus Torvalds
e140f731f9 Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull more SCSI updates from James Bottomley:
 "Mostly small bug fixes and trivial updates.

  The major new core update is a change to the way device, target and
  host reference counting is done to try to make it more robust (this
  change has soaked for a while to try to winkle out any bugs)"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: pm8001: Fix typo 'the the' in comment
  scsi: megaraid_sas: Remove redundant variable cmd_type
  scsi: FlashPoint: Remove redundant variable bm_int_st
  scsi: zfcp: Fix missing auto port scan and thus missing target ports
  scsi: core: Call blk_mq_free_tag_set() earlier
  scsi: core: Simplify LLD module reference counting
  scsi: core: Make sure that hosts outlive targets
  scsi: core: Make sure that targets outlive devices
  scsi: ufs: ufs-pci: Correct check for RESET DSM
  scsi: target: core: De-RCU of se_lun and se_lun acl
  scsi: target: core: Fix race during ACL removal
  scsi: ufs: core: Correct ufshcd_shutdown() flow
  scsi: ufs: core: Increase the maximum data buffer size
  scsi: lpfc: Check the return value of alloc_workqueue()
2022-08-13 13:41:48 -07:00
Linus Torvalds
c993e07be0 Merge tag 'dma-mapping-5.20-2022-08-06' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:

 - convert arm32 to the common dma-direct code (Arnd Bergmann, Robin
   Murphy, Christoph Hellwig)

 - restructure the PCIe peer to peer mapping support (Logan Gunthorpe)

 - allow the IOMMU code to communicate an optional DMA mapping length
   and use that in scsi and libata (John Garry)

 - split the global swiotlb lock (Tianyu Lan)

 - various fixes and cleanup (Chao Gao, Dan Carpenter, Dongli Zhang,
   Lukas Bulwahn, Robin Murphy)

* tag 'dma-mapping-5.20-2022-08-06' of git://git.infradead.org/users/hch/dma-mapping: (45 commits)
  swiotlb: fix passing local variable to debugfs_create_ulong()
  dma-mapping: reformat comment to suppress htmldoc warning
  PCI/P2PDMA: Remove pci_p2pdma_[un]map_sg()
  RDMA/rw: drop pci_p2pdma_[un]map_sg()
  RDMA/core: introduce ib_dma_pci_p2p_dma_supported()
  nvme-pci: convert to using dma_map_sgtable()
  nvme-pci: check DMA ops when indicating support for PCI P2PDMA
  iommu/dma: support PCI P2PDMA pages in dma-iommu map_sg
  iommu: Explicitly skip bus address marked segments in __iommu_map_sg()
  dma-mapping: add flags to dma_map_ops to indicate PCI P2PDMA support
  dma-direct: support PCI P2PDMA pages in dma-direct map_sg
  dma-mapping: allow EREMOTEIO return code for P2PDMA transfers
  PCI/P2PDMA: Introduce helpers for dma_map_sg implementations
  PCI/P2PDMA: Attempt to set map_type if it has not been set
  lib/scatterlist: add flag for indicating P2PDMA segments in an SGL
  swiotlb: clean up some coding style and minor issues
  dma-mapping: update comment after dmabounce removal
  scsi: sd: Add a comment about limiting max_sectors to shost optimal limit
  ata: libata-scsi: cap ata_device->max_sectors according to shost->max_sectors
  scsi: scsi_transport_sas: cap shost opt_sectors according to DMA optimal limit
  ...
2022-08-06 10:56:45 -07:00
Linus Torvalds
746fc76b82 Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
 "Updates to the usual drivers (ufs, qla2xx, target, lpfc, smartpqi,
  mpi3mr).

  The main driver change that might cause issues on down the road is the
  conversion of some of our oldest surviving drivers to the DMA API
  (should only affect m68k).

  The only major core change is the rework of async resume; the rest are
  either completely trivial or for updating deprecated APIs"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (195 commits)
  scsi: target: Remove XDWRITEREAD emulated support
  scsi: megaraid: Remove the static variable initialisation
  scsi: ch: Do not initialise statics to 0
  scsi: ufs: core: Fix spelling mistake "Cannnot" -> "Cannot"
  scsi: target: iscsi: Do not require target authentication
  scsi: target: iscsi: Allow AuthMethod=None
  scsi: target: iscsi: Support base64 in CHAP
  scsi: target: iscsi: Add support for extended CDB AHS
  scsi: ufs: dt-bindings: Add SC8280XP binding
  scsi: target: iscsi: Fix clang -Wformat warnings
  scsi: ufs: core: Read device property for ref clock
  scsi: libsas: Resume SAS host for phy reset or enable via sysfs
  scsi: hisi_sas: Modify v3 HW SATA completion error processing
  scsi: hisi_sas: Relocate DMA unmap of SMP task
  scsi: hisi_sas: Remove unnecessary variable to hold DMA map elements
  scsi: hisi_sas: Call hisi_sas_slave_configure() from slave_configure_v3_hw()
  scsi: mpi3mr: Delete a stray tab
  scsi: mpi3mr: Unlock on error path
  scsi: mpi3mr: Reduce VD queue depth on detecting throttling
  scsi: mpi3mr: Resource Based Metering
  ...
2022-08-04 19:47:37 -07:00
Ming Lei
16728aaba6 scsi: core: Make sure that hosts outlive targets
Fix the race conditions between SCSI LLD kernel module unloading and SCSI
device and target removal by making sure that SCSI hosts are destroyed
after all associated target and device objects have been freed.

Link: https://lore.kernel.org/r/20220728221851.1822295-3-bvanassche@acm.org
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Mike Christie <michael.christie@oracle.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: John Garry <john.garry@huawei.com>
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
[ bvanassche: Reworked Ming's patch and split it ]
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-08-01 19:45:14 -04:00
Bart Van Assche
fe44260419 scsi: core: Make sure that targets outlive devices
This commit prevents that the following sequence triggers a kernel crash:

 - Deletion of a SCSI device is requested via sysfs. Device removal takes
   some time because blk_cleanup_queue() is waiting for the SCSI error
   handler.

 - The SCSI target associated with that SCSI device is removed.

 - scsi_remove_target() returns and its caller frees the resources
   associated with the SCSI target.

 - The error handler makes progress and invokes an LLD callback that
   dereferences the SCSI target pointer.

Link: https://lore.kernel.org/r/20220728221851.1822295-2-bvanassche@acm.org
Cc: Christoph Hellwig <hch@lst.de>
Cc: Mike Christie <michael.christie@oracle.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: John Garry <john.garry@huawei.com>
Cc: Li Zhijian <lizhijian@fujitsu.com>
Reported-by: Mike Christie <michael.christie@oracle.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-08-01 19:45:13 -04:00
John Garry
608128d391 scsi: sd: allow max_sectors be capped at DMA optimal size limit
Streaming DMA mappings may be considerably slower when mappings go through
an IOMMU and the total mapping length is somewhat long. This is because the
IOMMU IOVA code allocates and free an IOVA for each mapping, which may
affect performance.

New member Scsi_Host.opt_sectors is added, which is the optimal host
max_sectors, and use this value to cap the request queue max_sectors when
set.

It could be considered to have request queues io_opt value initially
set at Scsi_Host.opt_sectors in __scsi_init_queue(), but that is not
really the purpose of io_opt.

Finally, even though Scsi_Host.opt_sectors value should never be greater
than the request queue max_hw_sectors value, continue to limit to this
value for safety.

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2022-07-19 11:11:49 +02:00
Bart Van Assche
2599cac57a scsi/core: Use the new blk_opf_t type
Use the new blk_opf_t type for arguments and variables that represent
request flags. Use the !! operator in scsi_noretry_cmd() to convert the
blk_opf_t type into a boolean. This patch does not change any functionality.

Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: John Garry <john.garry@huawei.com>
Cc: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220714180729.1065367-42-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-14 12:14:32 -06:00
Bart Van Assche
ea957547e8 scsi/core: Improve static type checking
Improve static type checking by using the new blk_opf_t type for the
combination of a request operation and its flags.

Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: John Garry <john.garry@huawei.com>
Cc: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220714180729.1065367-40-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-14 12:14:32 -06:00
John Garry
2dd6532e95 blk-mq: Drop 'reserved' arg of busy_tag_iter_fn
We no longer use the 'reserved' arg in busy_tag_iter_fn for any iter
function so it may be dropped.

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me> #nvme
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/1657109034-206040-6-git-send-email-john.garry@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-06 06:33:53 -06:00
Mike Christie
6e637b723d scsi: libiscsi: Improve conn_send_pdu API
The conn_send_pdu API is evil in that it returns a pointer to an
iscsi_task, but that task might have been freed already so you can't touch
it. This patch splits the task allocation and transmission, so functions
like iscsi_send_nopout() can access the task before its sent and do
whatever bookkeeping is needed before it is sent.

Link: https://lore.kernel.org/r/20220616224557.115234-10-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-21 21:19:23 -04:00
Mike Christie
e1c6a7ec14 scsi: iscsi: Remove iscsi_get_task back_lock requirement
We currently require that the back_lock is held when calling the functions
that manipulate the iscsi_task refcount. The only reason for this is to
handle races where we are handling SCSI-ml EH callbacks and the cmd is
completing at the same time the normal completion path is running, and we
can't return from the EH callback until the driver has stopped accessing
the cmd. Holding the back_lock while also accessing the task->state made it
simple to check that a cmd is completing and also get/put a refcount at the
same time, and at the time we were not as concerned about performance.

The problem is that we don't want to take the back_lock from the xmit path
for normal I/O since it causes contention with the completion path if the
user has chosen to try and split those paths on different CPUs (in this
case abusing the CPUs and ignoring caching improves perf for some uses).

Begins to remove the back_lock requirement for iscsi_get/put_task by
removing the requirement for the get path. Instead of always holding the
back_lock we detect if something has done the last put and is about to call
iscsi_free_task(). A subsequent commit will then allow iSCSI code to do the
last put on a task and only grab the back_lock if the refcount is now zero
and it's going to call iscsi_free_task().

Link: https://lore.kernel.org/r/20220616224557.115234-8-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-21 21:19:23 -04:00
Mike Christie
8af809966c scsi: iscsi: Add recv workqueue helpers
Add helpers to allow the drivers to run their recv paths from libiscsi's
workqueue.

Link: https://lore.kernel.org/r/20220616224557.115234-3-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-21 21:19:22 -04:00
Mike Christie
4b9f8ce4d5 scsi: iscsi: Rename iscsi_conn_queue_work()
Rename iscsi_conn_queue_work() to iscsi_conn_queue_xmit() to reflect that
it handles queueing of xmits only.

Link: https://lore.kernel.org/r/20220616224557.115234-2-michael.christie@oracle.com
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Wu Bo <wubo40@huawei.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-21 21:19:22 -04:00
Mike Christie
31500e9027 scsi: iscsi: Fix session removal on shutdown
When the system is shutting down, iscsid is not running so we will not get
a response to the ISCSI_ERR_INVALID_HOST error event. The system shutdown
will then hang waiting on userspace to remove the session.

This has libiscsi force the destruction of the session from the kernel when
iscsi_host_remove() is called from a driver's shutdown callout.

This fixes a regression added in qedi boot with commit d1f2ce7763 ("scsi:
qedi: Fix host removal with running sessions") which made qedi use the
common session removal function that waits on userspace instead of rolling
its own kernel based removal.

Link: https://lore.kernel.org/r/20220616222738.5722-7-michael.christie@oracle.com
Fixes: d1f2ce7763 ("scsi: qedi: Fix host removal with running sessions")
Tested-by: Nilesh Javali <njavali@marvell.com>
Reviewed-by: Lee Duncan <lduncan@suse.com>
Reviewed-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-21 21:14:54 -04:00
Mike Christie
bb42856bfd scsi: iscsi: Add helper to remove a session from the kernel
During qedi shutdown we need to stop the iSCSI layer from sending new nops
as pings and from responding to target ones and make sure there is no
running connection cleanups. Commit d1f2ce7763 ("scsi: qedi: Fix host
removal with running sessions") converted the driver to use the libicsi
helper to drive session removal, so the above issues could be handled. The
problem is that during system shutdown iscsid will not be running so when
we try to remove the root session we will hang waiting for userspace to
reply.

Add a helper that will drive the destruction of sessions like these during
system shutdown.

Link: https://lore.kernel.org/r/20220616222738.5722-5-michael.christie@oracle.com
Tested-by: Nilesh Javali <njavali@marvell.com>
Reviewed-by: Nilesh Javali <njavali@marvell.com>
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-21 21:14:54 -04:00
Max Gurtovoy
6a33ed5064 scsi: iscsi: Make iscsi_unregister_transport() return void
This function always returns 0. We can make it return void to simplify the
code. Also, no caller ever checks the return value of this function.

Link: https://lore.kernel.org/r/20220616080210.18531-1-mgurtovoy@nvidia.com
Reviewed-by: Mike Christie <michael.christie@oracle.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-16 22:11:18 -04:00
Damien Le Moal
3dafe0648d scsi: libsas: Introduce struct smp_rps_resp
Similarly to sas report general and discovery responses, define the
structure struct smp_rps_resp to handle SATA PHY report responses using a
structure with a size that is exactly equal to the sas defined response
size.

With this change, struct smp_resp becomes unused and is removed.

Link: https://lore.kernel.org/r/20220609022456.409087-4-damien.lemoal@opensource.wdc.com
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-10 13:08:06 -04:00
Damien Le Moal
44f2bfe9ef scsi: libsas: Introduce struct smp_rg_resp
When compiling with gcc 12, several warnings are thrown by gcc when
compiling drivers/scsi/libsas/sas_expander.c, e.g.:

In function ‘sas_get_ex_change_count’,
    inlined from ‘sas_find_bcast_dev’ at
    drivers/scsi/libsas/sas_expander.c:1816:8:
drivers/scsi/libsas/sas_expander.c:1781:20: warning: array subscript
‘struct smp_resp[0]’ is partly outside array bounds of ‘unsigned
char[32]’ [-Warray-bounds]
 1781 |         if (rg_resp->result != SMP_RESP_FUNC_ACC) {
      |             ~~~~~~~^~~~~~~~

This is due to the use of the struct smp_resp to aggregate all possible
response types using a union but allocating a response buffer with a size
exactly equal to the size of the response type needed. This leads to access
to fields of struct smp_resp from an allocated memory area that is smaller
than the size of struct smp_resp.

Fix this by defining struct smp_rg_resp for sas report general responses.

Link: https://lore.kernel.org/r/20220609022456.409087-3-damien.lemoal@opensource.wdc.com
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-10 13:08:06 -04:00
Damien Le Moal
c3752f4460 scsi: libsas: Introduce struct smp_disc_resp
When compiling with gcc 12, several warnings are thrown by gcc when
compiling drivers/scsi/libsas/sas_expander.c, e.g.:

In function ‘sas_get_phy_change_count’,
    inlined from ‘sas_find_bcast_phy.constprop’ at
drivers/scsi/libsas/sas_expander.c:1737:9:
drivers/scsi/libsas/sas_expander.c:1697:39: warning: array subscript
‘struct smp_resp[0]’ is partly outside array bounds of ‘unsigned
char[56]’ [-Warray-bounds]
 1697 |                 *pcc = disc_resp->disc.change_count;
      |                        ~~~~~~~~~~~~~~~^~~~~~~~~~~~~

This is due to the use of the struct smp_resp to aggregate all possible
response types using a union but allocating a response buffer with a size
exactly equal to the size of the response type needed. This leads to access
to fields of struct smp_resp from an allocated memory area that is smaller
than the size of struct smp_resp.

Fix this by defining struct smp_disc_resp for sas discovery operations.
Since this structure and the generic struct smp_resp are identical for
the little endian and big endian archs, move the definition of these
structures at the end of include/scsi/sas.h to avoid repeating their
definition.

Link: https://lore.kernel.org/r/20220609022456.409087-2-damien.lemoal@opensource.wdc.com
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-06-10 13:08:06 -04:00
Linus Torvalds
fbe86daca0 Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
 "This consists of a small set of driver updates (lpfc, ufs, mpt3sas
  mpi3mr, iscsi target). Apart from that this is mostly small fixes with
  very few core changes (the biggest one being VPD caching)"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (177 commits)
  scsi: target: tcmu: Avoid holding XArray lock when calling lock_page
  scsi: elx: efct: Remove NULL check after calling container_of()
  scsi: dpt_i2o: Drop redundant spinlock initialization
  scsi: qedf: Remove redundant variable op
  scsi: hisi_sas: Fix memory ordering in hisi_sas_task_deliver()
  scsi: fnic: Replace DMA mask of 64 bits with 47 bits
  scsi: mpi3mr: Add target device related sysfs attributes
  scsi: mpi3mr: Add shost related sysfs attributes
  scsi: elx: efct: Remove redundant memset() statement
  scsi: megaraid_sas: Remove redundant memset() statement
  scsi: mpi3mr: Return error if dma_alloc_coherent() fails
  scsi: hisi_sas: Fix rescan after deleting a disk
  scsi: hisi_sas: Use sas_ata_wait_after_reset() in IT nexus reset
  scsi: libsas: Refactor sas_ata_hard_reset()
  scsi: mpt3sas: Update driver version to 42.100.00.00
  scsi: mpt3sas: Fix junk chars displayed while printing ChipName
  scsi: ipr: Use kobj_to_dev()
  scsi: mpi3mr: Fix a NULL vs IS_ERR() bug in mpi3mr_bsg_init()
  scsi: bnx2fc: Avoid using get_cpu() in bnx2fc_cmd_alloc()
  scsi: libfc: Remove get_cpu() semantics in fc_exch_em_alloc()
  ...
2022-05-25 19:09:48 -07:00
Linus Torvalds
a3a8b54b4f Merge tag 'Wstringop-overflow-fixes-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux
Pull Wstringop-overflow fixes from Gustavo Silva:
 "Fix some -Wstringop-overflow warnings when building with GCC-11. All
  the patches have been in linux-next during the last development cycle.

  This is part of the ongoing efforts to globally enable
  -Wstringop-overflow"

* tag 'Wstringop-overflow-fixes-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
  drm/i915: Fix -Wstringop-overflow warning in call to intel_read_wm_latency()
  drm/amd/display: Fix Wstringop-overflow warnings in dc_link_dp.c
  scsi: fcoe: Fix Wstringop-overflow warnings in fcoe_wwn_from_mac()
2022-05-25 13:52:24 -07:00
John Garry
057e5fc033 scsi: libsas: Refactor sas_ata_hard_reset()
Create function sas_ata_wait_after_reset() from sas_ata_hard_reset() as
some LLDDs may want to check for a remote ATA phy is up after reset.

Link: https://lore.kernel.org/r/1652354134-171343-2-git-send-email-john.garry@huawei.com
Tested-by: Yihang Li <liyihang6@hisilicon.com>
Reviewed-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-05-19 20:16:25 -04:00
Davidlohr Bueso
848b89778e scsi: fcoe: Add a local_lock to fcoe_percpu
fcoe_get_paged_crc_eof() relies on the caller having preemption disabled to
ensure the per-CPU fcoe_percpu context remains valid throughout the
call. This is done by either holding spinlocks (such as bnx2fc_global_lock
or qedf_global_lock) or the get_cpu() from fcoe_alloc_paged_crc_eof(). This
last one breaks PREEMPT_RT semantics as there can be memory allocation and
end up sleeping in atomic contexts.

Introduce a local_lock_t to struct fcoe_percpu that will keep the non-RT
case the same, mapping to preempt_disable/enable, while RT will use a
per-CPU spinlock allowing the region to be preemptible but still maintain
CPU locality. The other users of fcoe_percpu are already safe in this
regard and do not require local_lock()ing.

Link: https://lore.kernel.org/r/20211117025956.79616-3-dave@stgolabs.net
Link: https://lore.kernel.org/r/20220506105758.283887-2-bigeasy@linutronix.de
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-05-16 21:26:50 -04:00
Martin K. Petersen
e60ac0b9e4 scsi: core: Cache VPD pages b0, b1, b2
The SCSI disk driver consults VPD pages b0 (Block Limits), b1 (Block Device
Characteristics), and b2 (Logical Block Provisioning). Instead of having
sd.c request these pages every revalidate cycle, cache them along with the
other commonly used VPDs.

Link: https://lore.kernel.org/r/20220302053559.32147-6-martin.petersen@oracle.com
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-05-02 16:59:11 -04:00
Martin K. Petersen
c92a6b5d63 scsi: core: Query VPD size before getting full page
We currently default to 255 bytes when fetching VPD pages during discovery.
However, we have had a few devices that are known to wedge if the requested
buffer exceeds a certain size. See commit af73623f5f ("[SCSI] sd: Reduce
buffer size for vpd request") which works around one example of this
problem in the SCSI disk driver.

With commit d188b0675b ("scsi: core: Add sysfs attributes for VPD pages
0h and 89h") we now risk triggering the same issue in the generic midlayer
code.

The problem with the ATA VPD page in particular is that the SCSI portion of
the page is trailed by 512 bytes of verbatim ATA Identify Device
information.  However, not all controllers actually provide the additional
512 bytes and will lock up if one asks for more than the 64 bytes
containing the SCSI protocol fields.

Instead of picking a new, somewhat arbitrary, number of bytes for the VPD
buffer size, start fetching the 4-byte header for each page. The header
contains the size of the page as far as the device is concerned. We can use
the reported size to specify the correct allocation length when
subsequently fetching the full page.

The header validation is done by a new helper function scsi_get_vpd_size()
and both scsi_get_vpd_page() and scsi_get_vpd_buf() now rely on this to
query the page size.

In addition, scsi_get_vpd_page() is simplified to mirror the logic in
scsi_get_vpd_page(). This involves removing the Supported VPD Pages lookup
prior to attempting to query a page. There does not appear any evidence,
even in the oldest SCSI specs, that this step is required. We already rely
on scsi_get_vpd_page() throughout the stack and this function never
consulted the Supported VPD Pages. Since this has not caused any problems
it should be safe to remove the precondition from scsi_get_vpd_page().

Instrumented runs also revealed that the Supported VPD Pages lookup had
little effect since the device page index often was larger than the
supplied buffer size. As a result, inquiries frequently bypassed the index
check and went through the "If we ran off the end of the buffer, give us
the benefit of the doubt" code path which assumed the page was present
despite not being listed. The revised code takes both the page size
reported by the device as well as the size of the buffer provided by the
scsi_get_vpd_page() caller into account.

Link: https://lore.kernel.org/r/20220302053559.32147-3-martin.petersen@oracle.com
Fixes: d188b0675b ("scsi: core: Add sysfs attributes for VPD pages 0h and 89h")
Reported-by: Maciej W. Rozycki <macro@orcam.me.uk>
Tested-by: Maciej W. Rozycki <macro@orcam.me.uk>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2022-05-02 16:59:10 -04:00