Pull vfs fixes from Al Viro:
"Fix several places that screw up cleanups after failures halfway
through opening a file (one open-coding filp_clone_open() and getting
it wrong, two misusing alloc_file()). That part is -stable fodder from
the 'work.open' branch.
And Christoph's regression fix for uapi breakage in aio series;
include/uapi/linux/aio_abi.h shouldn't be pulling in the kernel
definition of sigset_t, the reason for doing so in the first place had
been bogus - there's no need to expose struct __aio_sigset in
aio_abi.h at all"
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
aio: don't expose __aio_sigset in uapi
ocxlflash_getfile(): fix double-iput() on alloc_file() failures
cxl_getfile(): fix double-iput() on alloc_file() failures
drm_mode_create_lease_ioctl(): fix open-coded filp_clone_open()
... so that it could set both ->f_flags and ->f_mode, without callers
having to set ->f_flags manually.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
commit cd43c221bb ("scsi: cxlflash: Isolate external module
dependencies") introduced the use of ifdefs to avoid compilation errors
when one of the possible backend driver, CXL or OCXL, is not compiled.
Unfortunately, the wrong defines are used and the backend ops are never
assigned, leading to a kernel crash in any case when the cxlflash module is
loaded.
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Use new return type vm_fault_t for fault handler. For now, this is just
documenting that the function returns a VM_FAULT value rather than an
errno. Once all instances are converted, vm_fault_t will become a distinct
type.
Ref-> commit 1c8f422059 ("mm: change return type to vm_fault_t")
Previously, VM_FAULT_NOPAGE was returned without verifying return value of
vm_insert_pfn. The new inline vmf_insert_pfn() will address this issue by
returning correct VM_FAULT_* type from fault handler.
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Depending on the underlying transport, cxlflash has a dependency on either
the CXL or OCXL drivers, which are enabled via their Kconfig option.
Instead of having a module wide dependency on these config options, it is
better to isolate the object modules that are dependent on the CXL and OCXL
drivers and adjust the module dependencies accordingly.
This commit isolates the object files that are dependent on CXL and/or
OCXL. The cxl/ocxl fops used in the core driver are tucked under an ifdef to
avoid compilation errors.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
As a staging cleanup to support transport specific builds of the cxlflash
module, relocate device dependent assignments to header files. This will
avoid littering the core driver with conditional compilation logic.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The new header file, backend.h, that was recently added is missing the
include guards. This commit adds the guards.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
AFUs can only process a single AFU command at a time. This is enforced with
a global mutex situated within the AFU send routine. As this mutex has a
global scope, it has the potential to unnecessarily block commands destined
for other AFUs.
Instead of using a global mutex, transition the mutex to be per-AFU. This
will allow commands to only be blocked by siblings of the same AFU.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When a superpipe process that makes use of virtual LUNs is terminated or
killed abruptly, there is a possibility that the cxlflash driver could hang
and deprive other operations on the adapter.
The release fop registered to be invoked on a context close, detaches every
LUN associated with the context. The underlying service to detach the LUN
assumes it has been called with the read semaphore held, and releases the
semaphore before any operation that could be time consuming.
When invoked without holding the read semaphore, an opportunity is created
for the semaphore's count to become negative when it is temporarily released
during one of these potential lengthy operations. This negative count
results in subsequent acquisition attempts taking forever, leading to the
hang.
To support the current design point of holding the semaphore on the ioctl()
paths, the release fop should acquire it before invoking any ioctl services.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The kernel log can get filled with debug messages from send_cmd_ioarrin()
when dynamic debug is enabled for the cxlflash module and there is a lot of
legacy I/O traffic.
While these messages are necessary to debug issues that involve command
tracking, the abundance of data can overwrite other useful data in the
log. The best option available is to limit the messages that should serve
most of the common use cases.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The following Oops may be encountered if the device is reset, i.e. EEH
recovery, while there is heavy I/O traffic:
59:mon> t
[c000200db64bb680] c008000009264c40 cxlflash_queuecommand+0x3b8/0x500
[cxlflash]
[c000200db64bb770] c00000000090d3b0 scsi_dispatch_cmd+0x130/0x2f0
[c000200db64bb7f0] c00000000090fdd8 scsi_request_fn+0x3c8/0x8d0
[c000200db64bb900] c00000000067f528 __blk_run_queue+0x68/0xb0
[c000200db64bb930] c00000000067ab80 __elv_add_request+0x140/0x3c0
[c000200db64bb9b0] c00000000068daac blk_execute_rq_nowait+0xec/0x1a0
[c000200db64bba00] c00000000068dbb0 blk_execute_rq+0x50/0xe0
[c000200db64bba50] c0000000006b2040 sg_io+0x1f0/0x520
[c000200db64bbaf0] c0000000006b2e94 scsi_cmd_ioctl+0x534/0x610
[c000200db64bbc20] c000000000926208 sd_ioctl+0x118/0x280
[c000200db64bbcc0] c00000000069f7ac blkdev_ioctl+0x7fc/0xe30
[c000200db64bbd20] c000000000439204 block_ioctl+0x84/0xa0
[c000200db64bbd40] c0000000003f8514 do_vfs_ioctl+0xd4/0xa00
[c000200db64bbde0] c0000000003f8f04 SyS_ioctl+0xc4/0x130
[c000200db64bbe30] c00000000000b184 system_call+0x58/0x6c
When there is no room to send the I/O request, the cached room is refreshed
by reading the memory mapped command room value from the AFU. The AFU
register mapping is refreshed during a reset, creating a race condition that
can lead to the Oops above.
During a device reset, the AFU should not be unmapped until all the active
send threads quiesce. An atomic counter, cmds_active, is currently used to
track internal AFU commands and quiesce during reset. This same counter can
also be used for the active send threads.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The following Oops can occur when there is heavy I/O traffic and the host is
reset by a tool such as sg_reset.
[c000200fff3fbc90] c00800001690117c process_cmd_doneq+0x104/0x500
[cxlflash] (unreliable)
[c000200fff3fbd80] c008000016901648 cxlflash_rrq_irq+0xd0/0x150 [cxlflash]
[c000200fff3fbde0] c000000000193130 __handle_irq_event_percpu+0xa0/0x310
[c000200fff3fbea0] c0000000001933d8 handle_irq_event_percpu+0x38/0x90
[c000200fff3fbee0] c000000000193494 handle_irq_event+0x64/0xb0
[c000200fff3fbf10] c000000000198ea0 handle_fasteoi_irq+0xc0/0x230
[c000200fff3fbf40] c00000000019182c generic_handle_irq+0x4c/0x70
[c000200fff3fbf60] c00000000001794c __do_irq+0x7c/0x1c0
[c000200fff3fbf90] c00000000002a390 call_do_irq+0x14/0x24
[c000200e5828fab0] c000000000017b2c do_IRQ+0x9c/0x130
[c000200e5828fb00] c000000000009b04 h_virt_irq_common+0x114/0x120
When a context is reset, the pending commands are flushed and the AFU is
notified. Before the AFU handles this request there could be command
completion interrupts queued to PHB which are yet to be delivered to the
context. In this scenario, a context could receive an interrupt for a command
that has been flushed, leading to a possible crash when the memory for the
flushed command is accessed.
To resolve this problem, a boolean will indicate if the hardware queue is
ready to process interrupts or not. This can be evaluated in the interrupt
handler before proessing an interrupt.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The following Oops can occur if an internal command sent to the AFU does not
complete within the timeout:
[c000000ff101b810] c008000016020d94 term_mc+0xfc/0x1b0 [cxlflash]
[c000000ff101b8a0] c008000016020fb0 term_afu+0x168/0x280 [cxlflash]
[c000000ff101b930] c0080000160232ec cxlflash_pci_error_detected+0x184/0x230
[cxlflash]
[c000000ff101b9e0] c00800000d95d468 cxl_vphb_error_detected+0x90/0x150[cxl]
[c000000ff101ba20] c00800000d95f27c cxl_pci_error_detected+0xa4/0x240 [cxl]
[c000000ff101bac0] c00000000003eaf8 eeh_report_error+0xd8/0x1b0
[c000000ff101bb20] c00000000003d0b8 eeh_pe_dev_traverse+0x98/0x170
[c000000ff101bbb0] c00000000003f438 eeh_handle_normal_event+0x198/0x580
[c000000ff101bc60] c00000000003fba4 eeh_handle_event+0x2a4/0x338
[c000000ff101bd10] c0000000000400b8 eeh_event_handler+0x1f8/0x200
[c000000ff101bdc0] c00000000013da48 kthread+0x1a8/0x1b0
[c000000ff101be30] c00000000000b528 ret_from_kernel_thread+0x5c/0xb4
When an internal command times out, the command buffer is freed while it is
still in the pending commands list of the context. This corrupts the list and
when the context is cleaned up, a crash is encountered.
To resolve this issue, when an AFU command or TMF command times out, the
command should be deleted from the hardware queue pending command list before
freeing the buffer.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The following Oops can be encountered if a device removal or system shutdown
is initiated while an EEH recovery is in process:
[c000000ff2f479c0] c008000015256f18 cxlflash_pci_slot_reset+0xa0/0x100
[cxlflash]
[c000000ff2f47a30] c00800000dae22e0 cxl_pci_slot_reset+0x168/0x290 [cxl]
[c000000ff2f47ae0] c00000000003ef1c eeh_report_reset+0xec/0x170
[c000000ff2f47b20] c00000000003d0b8 eeh_pe_dev_traverse+0x98/0x170
[c000000ff2f47bb0] c00000000003f80c eeh_handle_normal_event+0x56c/0x580
[c000000ff2f47c60] c00000000003fba4 eeh_handle_event+0x2a4/0x338
[c000000ff2f47d10] c0000000000400b8 eeh_event_handler+0x1f8/0x200
[c000000ff2f47dc0] c00000000013da48 kthread+0x1a8/0x1b0
[c000000ff2f47e30] c00000000000b528 ret_from_kernel_thread+0x5c/0xb4
The remove handler frees AFU memory while the EEH recovery is in progress,
leading to a race condition. This can result in a crash if the recovery thread
tries to access this memory.
To resolve this issue, the cxlflash remove handler will evaluate the device
state and yield to any active reset or probing threads.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit enables the OCXL operations for the OCXL devices.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The cxlflash core driver resets the AFU when the master contexts are created
in the initialization or recovery paths. Today, the OCXL provider service to
perform this operation is pending implementation. To avoid a crash due to a
missing fop, log an error once and return success to continue with execution.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
While enabling a context on the link, a predefined callback can be registered
with the OCXL provider services to be notified on translation errors. These
errors can in turn be passed back to the user on a read operation.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
In order to protect the OCXL hardware contexts from getting clobbered, a
simple state machine is added to indicate when a context is in open, close or
start state. The expected states are validated throughout the code to prevent
illegal operations on a context. A mutex is added to protect writes to the
context state field.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The SISLite specification has been updated to define new synchronous interrupt
status bits. These bits are set by the AFU when a given PASID or EA is bad and
a synchronous interrupt is triggered.
The SISLite header file is updated to support these new bits. Note that there
are also some formatting updates to some of the existing bits to allow all of
the definitions to line up uniformly.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Similar to user contexts, master contexts also require that the per-context
LISN registers be programmed for certain AFUs. The mapped trigger page is
obtained from underlying transport and registered with AFU for each master
context.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The SISLite specification has been updated for OCXL to support communicating
data to generate AFU interrupts to the AFU. This includes a new capability bit
that is advertised for OCXL AFUs and new registers to hold the object handle
and translation PASID of each interrupt. For Power, the object handle is the
mapped trigger page. Note that because these mappings are kernel only, the
PASID of a kernel context must be used to satisfy the translation.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
OCXL requires that AFUs use an opaque object handle to represent an AFU
interrupt. The specification does not provide a common means to communicate
the object handle to the AFU - each AFU must define this within the AFU
specification. To support this model, the object handle must be passed back to
the core driver as it manages the AFU specification (SISLite) for cxlflash.
Note that for Power systems, the object handle is the effective address of the
trigger page.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The cxlflash core fop API requires a way to invoke the fault and release
handlers of underlying transports using their native file-based APIs. This
provides the core with the ability to insert selectively itself into the
processing stream of these operations for cleanup. Implement these two fops to
map and release when requested.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The cxlflash userspace API requires that users be able to mmap and release the
adapter context. Support mapping by implementing the AFU mmap fop to map the
context MMIO space and install the corresponding page table entry upon page
fault. Similarly, implement the AFU release fop to terminate and clean up the
context when invoked.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The cxlflash userspace API requires that users be able to read the adapter
context for any pending events or interrupts from the AFU. Support reading
various events by implementing the AFU read fop to copy out event data.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The cxlflash userspace API requires that users be able to poll the adapter
context for any pending events or interrupts from the AFU. Support polling on
various events by implementing the AFU poll fop using a waitqueue.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
User contexts request interrupts and are started using the "start work"
interface. Populate the start_work() fop to allocate and map interrupts before
starting the user context. As part of starting the context, update the user
process identification logic to properly derive the data required by the
SPA. Also, introduce a skeleton interrupt handler using a bitmap, flag, and
spinlock to track interrupts. This handler will be expanded in future commits.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Add support to map and unmap the irq space and manage irq registrations with
the kernel for each allocated AFU interrupt. Also support mapping the physical
trigger page to obtain an effective address that will be provided to the
cxlflash core in a future commit.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Add support to allocate and free AFU interrupts using the OCXL provider
services. The trigger page returned upon successful allocation will be mapped
and exposed to the cxlflash core in a future commit.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
As part of the context lifecycle, the associated process element within the
Shared Process Area (SPA) of the link must be updated. Each process is defined
by various parameters (pid, tid, PASID mm) that are stored in the SPA upon
starting a context and invalidated when a context is stopped.
Use the OCXL provider services to configure the SPA with the appropriate data
that is unique to the process when starting a context. Initially only kernel
contexts are supported and therefore these process values are not applicable.
Note that the OCXL service used has an optional callback for translation fault
error notification. While not used here, it will be expanded in a future
commit.
Also add a service to stop a context by terminating the corresponding PASID
and remove the process element from the SPA.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The first function of the link needs to configure the transaction layer
between the host and device. This is accomplished by a call to the OCXL
provider services.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
After reading and modifying the function configuration, setup the OCXL link
using the OCXL provider services. The link is released when the adapter is
unconfigured.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Use the PCI VPD services to support reading the VPD data of the underlying
adapter.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The AFU should be enabled following a successful configuration and disabled
near the end of the cleanup path.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Once the context is started, the assigned MMIO space can be mapped and
unmapped. Provide means to map and unmap the context MMIO space.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Once the adapter context is created, it needs to be started by assigning the
MMIO space for the context and by enabling the process element in the
link. This commit adds the skeleton for starting the context and assigns the
context specific MMIO space. Master contexts have access to the global MMIO
space while the rest have access to the context specific space.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When the AFU is configured, the global and per process MMIO regions are
presented by the configuration space. Save these regions and map the global
MMIO region that is used to access all of the control and provisioning data in
the AFU.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
On a PERST, the AFU image can be reloaded or left intact. Provide means to set
this image reload policy.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Provide means to obtain the process element of an adapter context as well as
locate an adapter context by file.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Allocate a file descriptor for an adapter context when requested. In order to
allocate inodes for the file descriptors, a pseudo filesystem is created and
used.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
A range of PASIDs are used as identifiers for the adapter contexts. These
contexts may be destroyed and created randomly. Use an IDR to keep track of
contexts that are in use and assign a unique identifier to new ones.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Add support to create and release the adapter contexts for OCXL and provide
means to specify certain contexts as a master.
The existing cxlflash core has a design requirement that each host will have a
single host context available by default. To satisfy this requirement, one
host adapter context is created when the hardware AFU is initialized. This is
returned by the get_context() fop.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Per the OCXL specification, the maximum PASID supported by the AFU is
indicated by a field within the configuration space. Similar to acTags,
implementations can choose to use any sub-range of PASID within their assigned
range. For cxlflash, the entire range is used.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The OCXL specification supports distributing acTags amongst different AFUs and
functions on the link. As cxlflash devices are expected to only support a
single AFU per function, the entire range that was assigned to the function is
also assigned to the AFU.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The host AFU configuration is read on the initialization path to identify the
features and configuration of the AFU. This data is cached for use in later
configuration steps.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The OCXL specification supports distributing acTags amongst different AFUs and
functions on the link. The platform-specific acTag range for the link is
obtained using the OCXL provider services and then assigned to the host
function based on implementation.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Per the OCXL specification, the underlying host can have multiple AFUs per
function with each function supporting its own configuration. The host
function configuration is read on the initialization path to evaluate the
number of functions present and identify the features and configuration of the
functions present. This data is cached for use in later configuration
steps. Note that for the OCXL hardware supported by the cxlflash driver, only
one AFU per function is expected.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When an adapter is initialized, transport specific configuration and MMIO
mapping details need to be saved. For CXL, this data is managed by the
underlying kernel module. To maintain a separation between the cxlflash core
and underlying transports, introduce a new structure to store data specific to
the OCXL AFU.
Initially only the pointers to underlying PCI and generic devices are added to
this new structure - it will be expanded further in future commits. Services
to create and destroy this hardware AFU are added and integrated in the probe
and exit paths of the driver.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Add initial infrastructure to support a new cxlflash transport, OCXL.
Claim a dependency on OCXL and add a new file, ocxl_hw.c, which will host the
backend routines that are specific to OCXL.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Checkpatch throws a warning when the argument identifier names are not
included in the function definitions.
To avoid these warnings, argument identifiers are added in the existing
function definitions.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The SISLite specification originally defined the context control register with
a single field of bits to represent the LISN and also stipulated that the
register reset value be 0. The cxlflash driver took advantage of this when
programming the LISN for the master contexts via an unconditional write - no
other bits were preserved.
When unmap support was added, SISLite was updated to define bit 0 of the
context control register as a way for the AFU to notify the context owner that
unmap operations were supported. Thus the assumptions under which the register
is setup changed and the existing unconditional write is clobbering the unmap
state for master contexts. This is presently not an issue due to the order in
which the context control register is programmed in relation to the unmap bit
being queried but should be addressed to avoid a future regression in the
event this code is moved elsewhere.
To remedy this issue, preserve the bits when programming the LISN field in the
context control register. Since the LISN will now be programmed using a read
value, assert that the initial state of the LISN field is as described in
SISLite (0).
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The number of interrupts requested for user contexts are stored in the context
specific structures and utilized to manage the interrupts. For the master
contexts, this number is only used once and therefore not saved.
To prepare for future commits where the number of interrupts will be required
in more than one place, preserve the value in the master context structure.
[mkp: typo in comment]
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
As staging to support future accelerator transports, add a shim layer
such that the underlying services the cxlflash driver requires can be
conditional upon the accelerator infrastructure.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Adapter context creation can return either NULL or an error pointer.
Updating the check condition to reflect this.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The CXL-specific work structure used to request the number of interrupts
currently resides as a nested member of both the context information and
hardware queue structures. It is used to cache values (specifically the
number of interrupts) required by the CXL layer when starting a context.
To facilitate staging that will ultimately allow the cxlflash core to
become agnostic of the underlying accelerator transport, remove these
embedded work structures.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The number of interrupts a user requests during a context attach is
presently stored within the CXL work ioctl structure that is nested
alongside the per context metadata. Keeping this data in a structure
that is tied to a particular hardware implementation (CXL) will only
complicate matters when supporting newer accelerator transports.
Instead of relying upon the number of interrupts being cached within
a CXL-specific structure, explicitly cache the value within the context
information structure.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Convert cxl-specific pointers to generic cookies to facilitate future
enhancements.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
In the event of a command failure, cxlflash returns the failure to the upper
layers to process. After processing the error, when the command is queued
again, the private command structure will not be zeroed and the ioasc could be
stale. Per the SISLite specification, the AFU only sets the ioasc in the
presence of a failure. Thus, even though the original command succeeds the
second time, the command is considered a failure due to stale ioasc. This
cycle repeats indefinitely and can cause a hang or IO failure.
To fix the issue, clear the ioasc before queuing any command.
[mkp: added Cc: stable per request]
Fixes: 479ad8e9d4 ("scsi: cxlflash: Remove zeroing of private command data")
Cc: <stable@vger.kernel.org>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Pull compat and uaccess updates from Al Viro:
- {get,put}_compat_sigset() series
- assorted compat ioctl stuff
- more set_fs() elimination
- a few more timespec64 conversions
- several removals of pointless access_ok() in places where it was
followed only by non-__ variants of primitives
* 'misc.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (24 commits)
coredump: call do_unlinkat directly instead of sys_unlink
fs: expose do_unlinkat for built-in callers
ext4: take handling of EXT4_IOC_GROUP_ADD into a helper, get rid of set_fs()
ipmi: get rid of pointless access_ok()
pi433: sanitize ioctl
cxlflash: get rid of pointless access_ok()
mtdchar: get rid of pointless access_ok()
r128: switch compat ioctls to drm_ioctl_kernel()
selection: get rid of field-by-field copyin
VT_RESIZEX: get rid of field-by-field copyin
i2c compat ioctls: move to ->compat_ioctl()
sched_rr_get_interval(): move compat to native, get rid of set_fs()
mips: switch to {get,put}_compat_sigset()
sparc: switch to {get,put}_compat_sigset()
s390: switch to {get,put}_compat_sigset()
ppc: switch to {get,put}_compat_sigset()
parisc: switch to {get,put}_compat_sigset()
get_compat_sigset()
get rid of {get,put}_compat_itimerspec()
io_getevents: Use timespec64 to represent timeouts
...
The cxlflash driver tracks process IDs alongside contexts to validate
context ownership. Currently, the process IDs are derived by directly
accessing values from the 'current' task pointer. While this method of
access is fine for the current process, it is incorrect when the parent
process ID is needed as the access requires serialization.
To address the incorrect issue and provide a consistent means of
deriving the process ID within the cxlflash driver, use the task
accessors defined linux/sched.h.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Currently, all adapters that cxlflash supports must have WWPN VPD
keywords to complete configuration. This was required as cards with
external FC ports needed to be programmed with WWPNs.
Newer supported cards do not have an external FC interface and therefore
do not require WWPN. To support backwards compatibility, these devices
have included 'dummy' WWPN VPD with WWPN values of zero. This however
places a dependency that all future cards have WWPN VPD, which may not
always be the case.
Allow for cards to not have WWPN, designating which cards are expected
to have it in order to configure properly.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The existing write same routine within the cxlflash driver uses a
statically defined value for the maximum write same transfer length.
While this is close to the value reflected by the original device that
was supported by cxlflash, newer devices are capable of much larger
lengths. Supporting what the device is capable of offers substantial
performance improvement as the scrub routine within cxlflash operates on
'chunk size' units (256MB with a 4K sector size).
Instead of a #define, use the write same maximum length that is stored
in the block layer in units of 512 byte sectors. This value is initially
determined from the block limits VPD page during device discovery and
can also be manipulated from sysfs. As a general cleanup, designate the
timeout used when executing the write same command as constant.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The ioctl DK_CAPI_VLUN_RESIZE can fail if the allocated vlun size is
reduced from almost maximum capacity and then increased again.
The shrink_lxt() routine is currently using the SISL_ASTATUS_MASK to
mask the higher 48 bits of the lxt entry. This is unnecessary and
incorrect as it uses a mask designed for the asynchronous interrupt
status register. When the 4 port support was added to cxlflash, the
SISL_ASTATUS_MASK was updated to reflect the status bits for all 4
ports. This change indirectly affected the shrink_lxt() code path.
To extract the base, simply shift the bits without masking.
Fixes: 5651807232 ("scsi: cxlflash: SISlite updates to support 4 ports")
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The AFU recovery routine uses an interruptible mutex to control the flow
of in-flight recoveries. Upon receiving an interruptible signal the code
branches to a common exit path which wrongly assumes the mutex is
held. Add a local variable to track when the mutex should be unlocked.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The AFU termination sequence has been refactored over time such that the
main tear down routine, term_afu(), can no longer can be invoked with a
NULL AFU pointer. Remove the unnecessary existence check from
term_afu().
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
'rc' is known to be 0 at this point. If 'create_context()' fails,
returns -ENOMEM instead of 0 which means success.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The copy_from/to_user() functions return the number of bytes remaining
to be copied but we had intended to return -EFAULT here.
Fixes: bc88ac47d5 ("scsi: cxlflash: Support AFU debug")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The device and host reset handler contain debug prints to help identify
the entities being reset. Today these reset handlers are based on a SCSI
EH design that uses a SCSI command reference as a means of identifying
the target entity. As such, the debug trace includes the SCSI command
pointer and associated CDB. This is not necessary as the SCSI command is
simply the messenger in these scenarios.
Refactor the debug prints in the host and reset handlers to only present
information that is applicable given the function scope.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The current send_tmf() implementation is based on the caller providing a
SCSI command reference. In reality all that is needed is a SCSI device
reference as the routine uses a private command.
Refactor send_tmf() to pass the private adapter configuration reference
and a SCSI device reference. As a nice side effect, this will ease the
burden of converting caller routines to be based solely off of a SCSI
device reference.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The device_unregister() service used when cleaning up the character
device is already responsible for the internal state associated with the
device upon successful creation. As the cxlflash driver does not obtain
a second reference to the character device, the explicit call to
put_device() is not required and can lead to an inconsistent sysfs among
other issues as the reference is no longer valid after the first
put_device() is performed.
Remove the unnecessary put_device() to remedy this issue.
Fixes: a834a36b57 ("scsi: cxlflash: Create character device to provide host management interface")
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Currently, the SCSI command presented to the device reset handler is used
to send TMFs to the AFU for a device reset. This behavior is incorrect as
the command presented is an actual command and not a special notification.
As such, it should only be used for reference and not be acted upon.
Additionally, the existing TMF transmission routine does not account for
actual errors from the hardware, only reflecting failure when a timeout
occurs. This can lead to a condition where the device reset handler is
presented with a false 'success'.
Update send_tmf() to dynamically allocate a private command for sending
the TMF command and properly reflect failure when the completed command
indicates an error or was aborted. Detect TMF commands during response
processing and avoid scsi_done() for these types of commands. Lastly,
update comments in the TMF processing paths to describe the new behavior.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The SCSI core now zeroes the per-command private data area prior to
calling into the LLD. Replace the clearing operation that takes place
when the private command data reference is obtained with a routine that
performs common initializations. The zeroing that takes place in the
device reset path remains intact as the private command data associated
with the specified SCSI command is not guaranteed to be cleared.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The cxlflash driver supports performing a write-same16 to scrub virtual
luns when they are released by a user. To date, AFUs for adapters that
are supported by cxlflash do not have the capability to unmap as part of
the WS operation. This can lead to fragmented flash devices which results
in performance degradation.
Future AFUs can optionally support unmap write-same commands and reflects
this support via the context control register. This provides userspace
applications with direct visibility such that they need not depend on a
host API.
Detect unmap support during cxlflash initialization by reading the context
control register associated with the primary hardware queue. Update the
existing write_same16() routine to set the unmap bit in the CDB when unmap
is supported by the host.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Adopt the SISLite AFU debug capability to allow future CXL Flash
adapters the ability to better debug AFU issues. Update the SISLite
header with the changes necessary to support AFU debug operations
and create a host ioctl interface for user debug software. Also
update the cxlflash documentation to describe this new host ioctl.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Adopt the SISLite AFU LUN provisioning capability to allow future CXL
Flash adapters the ability to better manage storage. Update the SISLite
header with the changes necessary to support LUN provision operations
and create a host ioctl interface for user LUN management software. Also
update the cxlflash documentation to describe this new host ioctl.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The existing AFU capability checking infrastructure is closely tied to
the command mode capability bits. In order to support new capabilities,
refactor the existing infrastructure to be more generic.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
As staging for supporting various host management functions, add a host
ioctl infrastructure to filter ioctl commands and perform operations that
are common for all host ioctls. Also update the cxlflash documentation to
create a new section for documenting host ioctls.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
To date the only supported internal AFU command is AFU sync. The logic
to send an internal AFU command is embedded in the specific AFU sync
handler and would need to be duplicated for new internal AFU commands.
In order to support new internal AFU commands, separate code that is
common for AFU internal commands into a generic transmission routine
and support passing back command status through an IOASA structure.
The first user of this new routine is the existing AFU sync command.
As a cleanup, use a descriptive name for the AFU sync command instead
of a magic number.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The cxlflash driver currently lacks host management interface. Future
devices supported by cxlflash will provide a variety of host-wide
management functions. Examples include LUN provisioning, hardware debug
support, and firmware download.
In order to provide a way to manage the device, a character device will
be created during probe of each adapter. This device will support a set of
ioctls defined in the SISLite specification from which administrators can
manage the adapter.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
To date, CXL flash devices do not support a single command abort operation.
Instead, the SISLite specification provides a context reset operation to
cleanup all pending commands for a given context.
When a context reset is successful, it is guaranteed that the AFU has
aborted all currently pending I/O. This sequence is less invasive than a
device or host reset and can be executed to support scsi command abort
requests. Add eh_abort_handler callback support to process command timeouts
and abort requests.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When the AFU is reset in an error path, pending scsi commands can be
silently dropped without completion or a formal abort. This puts the onus
on the cxlflash driver to notify mid-layer and indicating that the command
can be retried.
Once the card has been quiesced, the hardware send queue lock is acquired
to prevent any data movement while the pending commands are processed.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Currently, there is no book keeping of the pending scsi commands in the
cxlflash driver. This lack of tracking in-flight requests is too
restrictive and requires a heavy-hammer reset each time an adapter error is
encountered. Additionally, it does not allow for commands to be properly
retried.
In order to avoid this problem and to better handle error path command
cleanup, introduce a linked list for each hardware queue that tracks
pending commands.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
AFU sync operations are not currently evaluated for failure. This is
acceptable for paths where there is not a dependency on the AFU being
consistent with the host. Examples include link reset events and LUN
cleanup operations. On paths where there is a dependency, such as a LUN
open, a sync failure should be acted upon.
In the event of AFU sync failures, either log or cleanup as appropriate for
operations that are dependent on a successful sync completion.
Update documentation to reflect behavior in the event of an AFU sync
failure.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
A context reset failure indicates the AFU is in a bad state. At present,
when such a situation occurs, no further action is taken. This leaves the
adapter in an unusable state with no recoverable actions.
To avoid this situation, context reset failures will be escalated to a host
reset operation. This will be done asynchronously to allow the acting
thread to return to the user with a failure.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Per the SISLite specification, context_reset() writes 0x1 to the LSB of the
reset register. When the AFU processes this reset request, it is expected
to clear the bit after reset is complete. The current implementation simply
checks that the entire value read back is not 1, instead of masking off the
LSB and evaluating it for a change to 0. Should the AFU manipulate other
bits during the reset (reading back a value of 0xF for example), successful
completion will be prematurely indicated given the existing logic.
Additionally, in the event that the context reset operation fails, there
does not currently exist a way to provide feedback to the initiator of the
reset. This poses a problem for the rare case that a context reset fails as
the caller will proceed on the assumption that all is well.
To remedy these issues, refactor the context reset routine to only mask off
the LSB when evaluating for success and return status to the caller. Also
update the context reset handler parameters to pass a hardware queue
reference instead of a single command to better reflect that the entire
queue associated with the context is impacted by the reset.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The cxlflash_afu_sync() routine returns a negative one to indicate any kind
of failure. This makes it impossible to establish why the error occurred.
Update the return codes to clearly indicate the failure cause to the
caller.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Currently there are separate spin locks for the two supported I/O queueing
models. This makes it difficult to serialize with paths outside the enqueue
path.
As a design simplification and to support serialization with enqueue
operations, move to only a single lock that is used for enqueueing
regardless of the queueing model.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The driver now uses IRQ_POLL and needs to select it to avoid the
following build error.
ERROR: ".irq_poll_complete" [drivers/scsi/cxlflash/cxlflash.ko] undefined!
ERROR: ".irq_poll_sched" [drivers/scsi/cxlflash/cxlflash.ko] undefined!
ERROR: ".irq_poll_disable" [drivers/scsi/cxlflash/cxlflash.ko] undefined!
ERROR: ".irq_poll_init" [drivers/scsi/cxlflash/cxlflash.ko] undefined!
Fixes: cba06e6de4 ("scsi: cxlflash: Implement IRQ polling for RRQ processing")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
As an enhancement to distribute requests to multiple hardware queues, add the
infrastructure to hash a SCSI command into a particular hardware queue.
Support the following scenarios when deriving which queue to use: single
queue, tagging when SCSI-MQ enabled, and simple hash via CPU ID when SCSI-MQ
is disabled. Rather than altering the existing send API, the derived hardware
queue is stored in the AFU command where it can be used for sending a command
to the chosen hardware queue.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
As staging for supporting multiple hardware queues, add an attribute to show
and set the current number of hardware queues for the host. Support specifying
a hard limit or a CPU affinitized value. This will allow the number of
hardware queues to be tuned by a system administrator.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Introduce multiple hardware queues to improve legacy I/O path performance.
Each hardware queue is comprised of a master context and associated I/O
resources. The hardware queues are initially implemented as a static array
embedded in the AFU. This will be transitioned to a dynamic allocation in a
later series to improve the memory footprint of the driver.
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The method used to decode asynchronous interrupts involves unnecessary loops
to match up bits that are set with corresponding entries in the asynchronous
interrupt information table. This algorithm is wasteful and does not scale
well as new status bits are supported.
As an improvement, use the for_each_set_bit() service to iterate over the
asynchronous status bits and refactor the information table such that it can
be indexed by bit position.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
As a general cleanup, address all reasonable checkpatch warnings and
errors. These include enforcement of comment styles and including named
identifiers in function prototypes.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Validation statements to enforce assumptions about specific defines are not
being evaluated by the compiler due to the fact that they reside in a routine
that is not used. To activate them, call the routine as part of module
initialization. As an additional, related cleanup, remove the now-defunct
CXLFLASH_NUM_CMDS.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Devices supported by the cxlflash driver are fully coherent and do not require
a bus address mapping. Avoid unnecessary path length by using the virtual
address and length already present in the scatter-gather entry.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
An EEH during probe can lead to a crash as the recovery thread races with the
probe thread. To avoid this issue, introduce new states to fence out EEH
recovery until probe has completed. Also ensure the reset wait queue is
flushed during device removal to avoid orphaned threads.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Update the driver to allow for future cards with 4 ports.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
