John Soni Jose [Wed, 19 Aug 2015 23:14:31 +0000 (04:44 +0530)]
be2iscsi: Bump the driver version
Signed-off-by: John Soni Jose <sony.john@avagotech.com> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <JBottomley@Odin.com>
John Soni Jose [Wed, 19 Aug 2015 23:14:30 +0000 (04:44 +0530)]
be2iscsi: Fix updating the next pointer during WRB posting
While posting WRB the next_pointer of the current WRB should point
to itself and the previous WRB next_pointer should point to the
current WRB.
The next pointer value was retrieved during alloc_pdu and was updated
in wrb before ringing the doorbell. The fix retrieves the
next_pointer just before ringing the doorbell and updates in the WRB.
Signed-off-by: John Soni Jose <sony.john@avagotech.com> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <JBottomley@Odin.com>
scsi: restart list search after unlock in scsi_remove_target
When dropping a lock while iterating a list we must restart the search
as other threads could have manipulated the list under us. Without this
we can get stuck in an endless loop. This bug was introduced by
Thanks go to Dan Williams <dan.j.williams@intel.com> for tracking all this
prior history down.
Reported-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Fixes: bc3f02a795d3b4faa99d37390174be2a75d091bd Cc: stable@vger.kernel.org Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:16:32 +0000 (15:16 -0500)]
cxlflash: Fix to avoid bypassing context cleanup
Contexts may be skipped over for cleanup in situations where contention
for the adapter's table-list mutex is experienced in the presence of a
signal during the execution of the release handler.
This can lead to two known issues:
- A hang condition on remove as that path tries to wait for users to
cleanup - something that will never complete should this scenario play
out as the user has already cleaned up from their perspective.
- An Oops in the unmap_mapping_range() call that is made as part of
the user waiting mechanism that is invoked on remove when contexts
are found to still exist.
The root cause of this issue can be found in get_context() and how the
table-list mutex is acquired. As this code path is shared by several
different access points within the driver, a decision was made during
the development cycle to acquire this mutex in this location using the
interruptible version of the mutex locking service. In almost all of
the use-cases and environmental scenarios this holds up, even when the
mutex is contended. However, for critical system threads (such as the
release handler), failing to acquire the mutex and bailing with the
intention of the user being able to try again later is unacceptable.
In such a scenario, the context _must_ be derived as it is on an
irreversible path to being freed. Without being able to derive the
context, the code mistakenly assumes that it has already been freed
and proceeds to free up the underlying CXL context resources. From
this point on, any usage of [the now stale] CXL context resources
will result in undefined behavior. This is root cause of the Oops
mentioned as the second known issue as the mapping passed to the
unmap_mapping_range() service is owned by the CXL context.
To fix this problem, acquisition of the table-list mutex within
get_context() is simply changed to use the uninterruptible version
of the mutex locking service. This is safe as the timing windows for
holding this mutex are short and also protected against blocking.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Manoj Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:16:24 +0000 (15:16 -0500)]
cxlflash: Fix to avoid lock instrumentation rejection
When running with lock instrumentation (e.g. lockdep), some of the
instrumentation can become disabled at probe time for a cxlflash
adapter. This is due to a missing lock registration for the tmf_slock.
The fix is to call spin_lock_init() for the tmf_slock during probe.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Manoj Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:16:15 +0000 (15:16 -0500)]
cxlflash: Fix to avoid corrupting port selection mask
The port selection mask of a LUN can be corrupted when the manage LUN
ioctl (DK_CXLFLASH_MANAGE_LUN) is issued more than once for any device.
This mask indicates to the AFU which port[s] can be used for a data
transfer to/from a particular LUN. The mask is critical to ensuring the
correct behavior when using the virtual LUN function of this adapter.
When the mask is configured for both ports, an I/O may be sent to either
port as the AFU assumes that each port has access to the same physical
device (specified by LUN ID in the port LUN table).
In a situation where the mask becomes incorrectly configured to reflect
access to both ports when in fact there is only access through a single
port, an I/O can be targeted to the wrong physical device. This can lead
to data corruption among other ill effects (e.g. security leaks).
The cause for this corruption is the assumption that the ioctl will only
be called a second time for a LUN when it is being configured for access
via a second port. A boolean 'newly_created' variable is used to
differentiate between a LUN that was created (and subsequently configured
for single port access) and one that is destined for access across both
ports. While initially set to 'true', this sticky boolean is toggled to
the 'false' state during a lookup on any next ioctl performed on a device
with a matching WWN/WWID. The code fails to realize that the match could
in fact be the same device calling in again. From here, an assumption is
made that any LUN with 'newly_created' set to 'false' is configured for
access over both ports and the port selection mask is set to reflect this.
Any future attempts to use this LUN for hosting a virtual LUN will result
in the port LUN table being incorrectly programmed.
As a remedy, the 'newly_created' concept was removed entirely and replaced
with code that always constructs the port selection mask based upon the
SCSI channel of the LUN being accessed. The bits remain sticky, therefore
allowing for a device to be accessed over both ports when that is in fact
the correct physical configuration.
Also included in this commit are a few minor related changes to enhance
the fix and provide better debug information for port selection mask and
port LUN table bugs in the future. These include renaming refresh_local()
to lookup_local(), tracing the WWN/WWID as a big-endian entity, and
tracing the port selection mask, SCSI channel, and LUN ID each time the
port LUN table is programmed.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Manoj Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Manoj Kumar [Wed, 21 Oct 2015 20:16:07 +0000 (15:16 -0500)]
cxlflash: Fix to escalate to LINK_RESET on login timeout
A 'login timed out' asynchronous error interrupt is generated if no
response is seen to a FLOGI within 2 seconds. If the time out error
is not escalated to a LINK_RESET the port will not be available for
use. This fix provides the required escalation.
Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:16:00 +0000 (15:16 -0500)]
cxlflash: Fix to avoid leaving dangling interrupt resources
When running with an unsupported AFU, the cxlflash driver fails
the probe. When the driver is removed, the following Oops is
encountered on a show_interrupts() thread:
The Oops is due to not cleaning up correctly on the unsupported
AFU error path, leaving various allocated and registered resources.
In this case, interrupts are in a semi-allocated/registered state,
which the show_interrupts() thread attempts to use.
To fix, the cleanup logic in init_afu() is consolidated to error
gates at the bottom of the function and the appropriate goto is
added to each error path. As a mini side fix while refactoring
in this routine, the else statement following the AFU version
evaluation is eliminated as it is not needed.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Manoj Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:15:52 +0000 (15:15 -0500)]
cxlflash: Fix to avoid potential deadlock on EEH
Ioctl threads that use scsi_execute() can run for an excessive amount
of time due to the fact that they have lengthy timeouts and retry logic
built in. Under normal operation this is not an issue. However, once EEH
enters the picture, a long execution time coupled with the possibility
that a timeout can trigger entry to the driver via registered reset
callbacks becomes a liability.
In particular, a deadlock can occur when an EEH event is encountered
while in running in scsi_execute(). As part of the recovery, the EEH
handler drains all currently running ioctls, waiting until they have
completed before proceeding with a reset. As the scsi_execute()'s are
situated on the ioctl path, the EEH handler will wait until they (and
the remainder of the ioctl handler they're associated with) have
completed. Normally this would not be much of an issue aside from the
longer recovery period. Unfortunately, the scsi_execute() triggers a
reset when it times out. The reset handler will see that the device is
already being reset and wait until that reset completed. This creates
a condition where the EEH handler becomes stuck, infinitely waiting for
the ioctl thread to complete.
To avoid this behavior, temporarily unmark the scsi_execute() threads
as an ioctl thread by releasing the ioctl read semaphore. This allows
the EEH handler to proceed with a recovery while the thread is still
running. Once the scsi_execute() returns, the ioctl read semaphore is
reacquired and the adapter state is rechecked in case it changed while
inside of scsi_execute(). The state check will wait if the adapter is
still being recovered or returns a failure if the recovery failed. In
the event that the adapter reset failed, the failure is simply returned
as the ioctl would be unable to continue.
Reported-by: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:15:45 +0000 (15:15 -0500)]
cxlflash: Correct trace string
The trace following the failure of alloc_mem() incorrectly identifies
which function failed. This can lead to misdiagnosing a failure.
Fix the string to correctly indicate that alloc_mem() failed.
Reported-by: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:15:37 +0000 (15:15 -0500)]
cxlflash: Fix to avoid corrupting adapter fops
The fops owned by the adapter can be corrupted in certain scenarios,
opening a window where certain fops are temporarily NULLed before being
reset to their proper value. This can potentially lead software to make
incorrect decisions, leaving the user with the inability to function as
intended.
An example of this behavior can be observed when there are a number of
users with a high rate of turn around (attach to LUN, perform an I/O,
detach from LUN, repeat). Every so often a user is given a valid
context and adapter file descriptor, but the file associated with the
descriptor lacks the correct read permission bit (FMODE_CAN_READ) and
thus the read system call bails before calling the valid read fop.
Background:
The fops is stored in the adapter structure to provide the ability to
lookup the adapter structure from within the fop handler. CXL services
use the file's private_data and at present, the CXL context does not
have a private section. In an effort to limit areas of the cxlflash
driver with code specific the superpipe function, a design choice was
made to keep the details of the fops situated away from the legacy
portions of the driver. This drove the behavior that the adapter fops
is set at the beginning of the disk attach ioctl handler when there
are no users present.
The corruption that this fix remedies is due to the fact that the fops
is initially defaulted to values found within a static structure. When
the fops is handed down to the CXL services later in the attach path,
certain services are patched. The fops structure remains correct until
the user count drops to 0 and the fops is reset, triggering the process
to repeat again. The user counts are tightly coupled with the creation
and deletion of the user context. If multiple users perform a disk
attach at the same time, when the user count is currently 0, some users
can be in the middle of obtaining a file descriptor and have not yet
reached the context creation code that [in addition to creating the
context] increments the user count. Subsequent users coming in to
perform the attach see that the user count is still 0, and reinitialize
the fops, temporarily removing the patched fops. The users that are in
the middle obtaining their file descriptor may then receive an invalid
descriptor.
The fix simply removes the user count altogether and moves the fops
initialization to probe time such that it is only performed one time
for the life of the adapter. In the future, if the CXL services adopt
a private member for their context, that could be used to store the
adapter structure reference and cxlflash could revert to a model that
does not require an embedded fops.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Manoj Kumar [Wed, 21 Oct 2015 20:15:30 +0000 (15:15 -0500)]
cxlflash: Fix to double the delay each time
The operator used to double the master context response delay
is incorrect and does not result in delay doubling.
To fix, use a left shift instead of the XOR operator.
Reported-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:15:22 +0000 (15:15 -0500)]
MAINTAINERS: Add cxlflash driver
Add stanza for cxlflash SCSI driver.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:15:14 +0000 (15:15 -0500)]
cxlflash: Fix to prevent stale AFU RRQ
Following an adapter reset, the AFU RRQ that resides in host memory
holds stale data. This can lead to a condition where the RRQ interrupt
handler tries to process stale entries and/or endlessly loops due to an
out of sync generation bit.
To fix, the AFU RRQ in host memory needs to be cleared after each reset.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:15:06 +0000 (15:15 -0500)]
cxlflash: Correct spelling, grammar, and alignment mistakes
There are several spelling and grammar mistakes throughout the
driver. Additionally there are a handful of places where there
are extra lines and unnecessary variables/statements. These are
a nuisance and pollute the driver.
Fix spelling and grammar issues. Update some comments for clarity and
consistency. Remove extra lines and a few unneeded variables/statements.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:14:56 +0000 (15:14 -0500)]
cxlflash: Fix to prevent EEH recovery failure
The process_sense() routine can perform a read capacity which
can take some time to complete. If an EEH occurs while waiting
on the read capacity, the EEH handler will wait to obtain the
context's mutex in order to put the context in an error state.
The EEH handler will sit and wait until the context is free,
but this wait can potentially last forever (deadlock) if the
scsi_execute() that performs the read capacity experiences a
timeout and calls into the reset callback. When that occurs,
the reset callback sees that the device is already being reset
and waits for the reset to complete. This leaves two threads
waiting on the other.
To address this issue, make the context unavailable to new,
non-system owned threads and release the context while calling
into process_sense(). After returning from process_sense() the
context mutex is reacquired and the context is made available
again. The context can be safely moved to the error state if
needed during the unavailable window as no other threads will
hold its reference.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:14:48 +0000 (15:14 -0500)]
cxlflash: Fix MMIO and endianness errors
Sparse uncovered several errors with MMIO operations (accessing
directly) and handling endianness. These can cause issues when
running in different environments.
Introduce __iomem and proper endianness tags/swaps where
appropriate to make driver sparse clean.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:14:40 +0000 (15:14 -0500)]
cxlflash: Fix function prolog parameters and return codes
Several function prologs have incorrect parameter names and return
code descriptions. This can lead to confusion when reviewing the
source and creates inaccurate documentation.
To remedy, update the function prologs to properly reflect parameter
names and return codes.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:14:32 +0000 (15:14 -0500)]
cxlflash: Remove unnecessary scsi_block_requests
The host reset handler is called with I/O already blocked, thus
there is no need to explicitly block and unblock I/O in the handler.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:14:24 +0000 (15:14 -0500)]
cxlflash: Correct behavior in device reset handler following EEH
When the device reset handler is entered while a reset operation
is taking place, the handler exits without actually sending a
reset (TMF) to the targeted device. This behavior is incorrect
as the device is not reset. Further complicating matters is the
fact that a success is returned even when the TMF was not sent.
To fix, the state is rechecked after coming out of the reset
state. When the state is normal, a TMF will be sent out.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:14:17 +0000 (15:14 -0500)]
cxlflash: Fix to prevent workq from accessing freed memory
The workq can process work in parallel with a remove event, leading
to a condition where the workq handler can access freed memory.
To remedy, the workq should be terminated prior to freeing memory. Move
the termination call earlier in remove and use cancel_work_sync() instead
of flush_work() as there is not a need to process any scheduled work when
shutting down.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:14:09 +0000 (15:14 -0500)]
cxlflash: Correct usage of scsi_host_put()
Currently, scsi_host_put() is being called prematurely in the
remove path and is missing entirely in an error cleanup path.
The former can lead to memory being freed too early with
subsequent access potentially corrupting data whilst the former
would result in a memory leak.
Move the usage on remove to be the last cleanup action taken
and introduce a call to scsi_host_put() in the one initialization
error path that does not use remove to cleanup.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:14:01 +0000 (15:14 -0500)]
cxlflash: Fix AFU version access/storage and add check
The AFU version is stored as a non-terminated string of bytes within
a 64-bit little-endian register. Presently the value is read directly
(no MMIO accessor) and is stored in a buffer that is not big enough
to contain a NULL terminator. Additionally the version obtained is not
evaluated against a known value to prevent usage with unsupported AFUs.
All of these deficiencies can lead to a variety of problems.
To remedy, use the correct MMIO accessor to read the version value into
a null-terminated buffer and add a check to prevent an incompatible AFU
from being used with this driver.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:13:54 +0000 (15:13 -0500)]
cxlflash: Remove dual port online dependency
At present, both ports must be online for the device to
configure properly. Remove this dependency and the unnecessary
internal LUN override logic as well. Additionally, as a refactoring
measure, change the return code variable name to match that used
throughout the driver.
With this change, the card will be able to configure even when the
link is down. At some later point when the link is transitioned to
'up', a link state change interrupt will trigger the port configuration.
Note that despite its void-like behavior, the function was left with a
return code for right now in case its behavior needs to be altered again
in the near future based on testing.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:13:45 +0000 (15:13 -0500)]
cxlflash: Fix async interrupt bypass logic
A bug was introduced earlier in the development cycle when cleaning
up logic statements. Instead of skipping bits that are not set, set
bits are skipped, causing async interrupts to not be handled correctly.
To fix, simply add back in the proper evaluation for an unset bit.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:13:37 +0000 (15:13 -0500)]
cxlflash: Fix host link up event handling
Following a link up event, the LUNs available to the host may
have changed. Without rescanning the host, the LUN topology is
unknown to the user. In such a state, the user would be unable
to locate provisioned resources.
To remedy, the host should be rescanned after a link up event.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:13:29 +0000 (15:13 -0500)]
cxlflash: Fix location of setting resid
The resid is incorrectly set which can lead to unnecessary retry
attempts by the stack. This is due to resid _always_ being set
using a value returned from the adapter. Instead, the value
should only be interpreted and set when in an underrun scenario.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:13:21 +0000 (15:13 -0500)]
cxlflash: Fix to avoid stall while waiting on TMF
Borrowing the TMF waitq's spinlock causes a stall condition when
waiting for the TMF to complete. To remedy, introduce our own spin
lock to serialize TMF and use the appropriate wait services.
Also add a timeout while waiting for a TMF completion. When a TMF
times out, report back a failure such that a bigger hammer reset
can occur.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:13:11 +0000 (15:13 -0500)]
cxlflash: Fix to avoid spamming the kernel log
During run-time the driver can be very chatty and spam the system
kernel log. Various print statements can be limited and/or moved
to development-only mode. Additionally, numerous prints can be
converted to trace the corresponding device. Lastly, one spelling
correction was made: 'entra' to 'extra'.
The following changes were made:
- pr_debug to pr_devel
- pr_debug to pr_debug_ratelimited
- pr_err to dev_err
- pr_debug to dev_dbg
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:12:39 +0000 (15:12 -0500)]
cxlflash: Refine host/device attributes
Implement the following suggestions and add two new attributes
to allow for debugging the port LUN table.
- use scnprintf() instead of snprintf()
- use DEVICE_ATTR_RO and DEVICE_ATTR_RW
Suggested-by: Shane Seymour <shane.seymour@hp.com> Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:12:00 +0000 (15:12 -0500)]
cxlflash: Correct naming of limbo state and waitq
Limbo is not an accurate representation of this state and is
also not consistent with the terminology that other drivers
use to represent this concept. Rename the state and and its
associated waitq to 'reset'.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:11:52 +0000 (15:11 -0500)]
cxlflash: Fix to avoid CXL services during EEH
During an EEH freeze event, certain CXL services should not be
called until after the hardware reset has taken place. Doing so
can result in unnecessary failures and possibly cause other ill
effects by triggering hardware accesses. This translates to a
requirement to quiesce all threads that may potentially use CXL
runtime service during this window. In particular, multiple ioctls
make use of the CXL services when acting on contexts on behalf of
the user. Thus, it is essential to 'drain' running ioctls _before_
proceeding with handling the EEH freeze event.
Create the ability to drain ioctls by wrapping the ioctl handler
call in a read semaphore and then implementing a small routine that
obtains the write semaphore, effectively creating a wait point for
all currently executing ioctls.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:11:43 +0000 (15:11 -0500)]
cxlflash: Fix context encode mask width
The context encode mask covers more than 32-bits, making it
a long integer. This should be noted by appending the ULL
width suffix to the mask.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:11:34 +0000 (15:11 -0500)]
cxlflash: Fix to avoid sizeof(bool)
Using sizeof(bool) is considered poor form for various reasons and
sparse warns us of that. Correct by changing type from bool to u8.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:11:26 +0000 (15:11 -0500)]
cxlflash: Fix data corruption when vLUN used over multiple cards
If the same virtual LUN is accessed over multiple cards, only accesses
made over the first card will be valid. Accesses made over the second
card will go to the wrong LUN causing data corruption.
This is because the global LUN's mode word was being used to determine
whether the LUN table for that card needs to be programmed. The mode
word would be setup by the first card, causing the LUN table for the
second card to not be programmed.
By unconditionally initializing the LUN table (not depending on the
mode word), the problem is avoided.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Matthew R. Ochs [Wed, 21 Oct 2015 20:11:18 +0000 (15:11 -0500)]
cxlflash: Fix potential oops following LUN removal
When a LUN is removed, the sdev that is associated with the LUN
remains intact until its reference count drops to 0. In order
to prevent an sdev from being removed while a context is still
associated with it, obtain an additional reference per-context
for each LUN attached to the context.
This resolves a potential Oops in the release handler when a
dealing with a LUN that has already been removed.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Manoj Kumar [Wed, 21 Oct 2015 20:11:10 +0000 (15:11 -0500)]
cxlflash: Fix read capacity timeout
The timeout value for read capacity is too small. Certain devices
may take longer to respond and thus the command may prematurely
timeout. Additionally the literal used for the timeout is stale.
Update the timeout to 30 seconds (matches the value used in sd.c)
and rework the timeout literal to a more appropriate description.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Manoj Kumar [Wed, 21 Oct 2015 20:11:00 +0000 (15:11 -0500)]
cxlflash: Replace magic numbers with literals
Magic numbers are not meaningful and can create confusion. As a
remedy, replace them with descriptive literals.
Replace 512 with literal MAX_SECTOR_UNIT.
Replace 5 with literal CMD_RETRIES.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Manoj Kumar [Wed, 21 Oct 2015 20:10:31 +0000 (15:10 -0500)]
cxlflash: Fix to avoid invalid port_sel value
If two concurrent MANAGE_LUN ioctls are issued with the same
WWID parameter, it would result in an incorrect value of port_sel.
This is because port_sel is modified without any locks being
held. If the first caller stalls after the return from
find_and_create_lun(), the value of port_sel will be set
incorrectly to indicate a single port, though in this case
it should have been set to both ports.
To fix, use the global mutex to serialize the lookup of the
WWID and the subsequent modification of port_sel.
Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Alan Stern [Mon, 3 Aug 2015 15:57:29 +0000 (11:57 -0400)]
SCSI: fix bug in scsi_dev_info_list matching
The "compatible" matching algorithm used for looking up old-style
blacklist entries in a scsi_dev_info_list is buggy. The core of the
algorithm looks like this:
if (memcmp(devinfo->vendor, vendor,
min(max, strlen(devinfo->vendor))))
/* not a match */
where max is the length of the device's vendor string after leading
spaces have been removed but trailing spaces have not. Because of the
min() computation, either entry could be a proper substring of the
other and the code would still think that they match.
In the case originally reported, the device's vendor and product
strings were "Inateck " and " ". These matched against
the following entry in the global device list:
{"", "Scanner", "1.80", BLIST_NOLUN}
because "" is a substring of "Inateck " and "" (the result of removing
leading spaces from the device's product string) is a substring of
"Scanner". The mistaken match prevented the system from scanning and
finding the device's second Logical Unit.
This patch fixes the problem by making two changes. First, the code
for leading-space removal is hoisted out of the loop. (This means it
will sometimes run unnecessarily, but since a large percentage of all
lookups involve the "compatible" entries in global device list, this
should be an overall improvement.) Second and more importantly, the
patch removes trailing spaces and adds a check to verify that the two
resulting strings are exactly the same length. This prevents matches
where one entry is a proper substring of the other.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Giulio Bernardi <ugilio@gmail.com> Tested-by: Giulio Bernardi <ugilio@gmail.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Alan Stern [Mon, 3 Aug 2015 15:57:21 +0000 (11:57 -0400)]
SCSI: refactor device-matching code in scsi_devinfo.c
In drivers/scsi/scsi_devinfo.c, the scsi_dev_info_list_del_keyed() and
scsi_get_device_flags_keyed() routines contain a large amount of
duplicate code for finding vendor/product matches in a
scsi_dev_info_list. This patch factors out the duplicate code and
puts it in a separate function, scsi_dev_info_list_find().
Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Suggested-by: Giulio Bernardi <ugilio@gmail.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
the kernel prints some warnings when compiled with CONFIG_DMA_API_DEBUG.
This is because the fnic driver doesn't check the return value of
pci_map_single().
[ 11.942770] scsi host12: fnic
[ 11.950811] ------------[ cut here ]------------
[ 11.950818] WARNING: at lib/dma-debug.c:937 check_unmap+0x47b/0x920()
[ 11.950821] fnic 0000:0c:00.0: DMA-API: device driver failed to check map error[device address=0x0000002020a30040] [size=44 bytes] [mapped as single]
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed By: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
bnx2fc: Do not log error for netevents that need no action
Do not log error for netevents that need no action such as
NETDEV_REGISTER 0x0005, NETDEV_CHANGEADDR, and NETDEV_CHANGENAME.
It results in logging error messages such as these
James Smart [Mon, 31 Aug 2015 20:48:22 +0000 (16:48 -0400)]
lpfc: Update version to 11.0.0.0 for upstream patch set
Signed-off-by: Dick Kennedy <dick.kennedy@avagotech.com> Signed-off-by: James Smart <james.smart@avagotech.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
James Smart [Mon, 31 Aug 2015 20:48:21 +0000 (16:48 -0400)]
lpfc: Fix default RA_TOV and ED_TOV in the FC/FCoE driver for all topologies
Initial link up defaults were not properly being tracked relative to
initial FLOGI or pt2pt PLOGI. Add code to initialize them.
Signed-off-by: Dick Kennedy <dick.kennedy@avagotech.com> Signed-off-by: James Smart <james.smart@avagotech.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
James Smart [Mon, 31 Aug 2015 20:48:19 +0000 (16:48 -0400)]
lpfc: The linux driver does not reinitiate discovery after a failed FLOGI
Forgot to clear FCF Discovery in-progress flag upon FLOGI failures.
Thus we didn't restart FLOGI.
Signed-off-by: Dick Kennedy <dick.kennedy@avagotech.com> Signed-off-by: James Smart <james.smart@avagotech.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
James Smart [Mon, 31 Aug 2015 20:48:18 +0000 (16:48 -0400)]
lpfc: Fix for discovery failure in PT2PT when FLOGI's ELS ACC response gets aborted
Fix for discovery failure in PT2PT when FLOGI's ELS ACC response gets aborted
Change login state machine to:
- Restart FLOGI if prior is ABTS'd
- Reject incoming FLOGIs if we have one pending
The above ensures that we always finish FLOGI processing, regardless
of who initated FLOGI, before processing PLOGI's.
Signed-off-by: Dick Kennedy <dick.kennedy@avagotech.com> Signed-off-by: James Smart <james.smart@avagotech.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
James Smart [Mon, 31 Aug 2015 20:48:17 +0000 (16:48 -0400)]
lpfc: Add support for Lancer G6 and 32G FC links
Signed-off-by: Dick Kennedy <dick.kennedy@avagotech.com> Signed-off-by: James Smart <james.smart@avagotech.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
lpfc_send_rscn_event() allocates data for sizeof(struct
lpfc_rscn_event_header) + payload_len, but claims that the data has size
of sizeof(struct lpfc_els_event_header) + payload_len. That leads to
buffer overruns.
Signed-off-by: Ales Novak <alnovak@suse.cz> Signed-off-by: James Smart <james.smart@avagotech.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Sebastian Herbszt <herbszt@gmx.de> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Signed-off-by: Sebastian Herbszt <herbszt@gmx.de> Signed-off-by: James Smart <james.smart@avagotech.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Nicholas Krause [Mon, 31 Aug 2015 20:48:13 +0000 (16:48 -0400)]
lpfc:Make the function lpfc_sli4_mbox_completions_pending static in order to comply with function prototype
This makes the function lpfc_sli4_mbox_completion's definition
static now in order to comply with its prototype being also
declared as static too.
Signed-off-by: Nicholas Krause <xerofoify@gmail.com> Signed-off-by: James Smart <james.smart@avagotech.com> Reviewed-by: Sebastian Herbszt <herbszt@gmx.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Ian Mitchell [Mon, 31 Aug 2015 20:48:12 +0000 (16:48 -0400)]
Fix kmalloc overflow in LPFC driver at large core count
This patch allows the LPFC to start up without a fatal kernel bug based
on an exceeded KMALLOC_MAX_SIZE and a too large NR_CPU-based maskbits
field. The bug was based on the number of CPU cores in a system.
Using the get_cpu_mask() function declared in kernel/cpu.c allows the
driver to load on the community kernel 4.2 RC1.
The proposed solution was approved by James Smart at Emulex and tested
on a UV2 machine with 6144 cores. With the fix, the LPFC module loads
with no unwanted effects on the system.
Signed-off-by: Ian Mitchell <imitchell@sgi.com> Signed-off-by: Alex Thorlton <athorlton@sgi.com> Suggested-by: Robert Elliot <elliott@hp.com>
[james.smart: resolve unused variable warning] Signed-off-by: James Smart <james.smart@avagotech.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Destroy lpfc_hba_index IDR on module exit, reclaiming the allocated memory.
This was detected by the following semantic patch (written by Luis Rodriguez
<mcgrof@suse.com>)
<SmPL>
@ defines_module_init @
declarer name module_init, module_exit;
declarer name DEFINE_IDR;
identifier init;
@@
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: James Smart <james.smart@avagotech.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Bodo Stroesser [Mon, 31 Aug 2015 20:48:10 +0000 (16:48 -0400)]
lpfc: in sli3 use configured sg_seg_cnt for sg_tablesize
Currently the module parameter lpfc_sg_seg_count does not have effect
for sli3 devices.
In lpfc_sli_driver_resource_setup(), which is used for sli3, the code
writes the configured sg_seg_cnt into lpfc_template.sg_tablesize.
But lpfc_template is the template used for sli4 only. Thus the value should
correctly be written to lpfc_template_s3->sg_tablesize.
This patch is for kernel 4.1-rc5, but is tested with lpfc 10.2.405.26 only.
Signed-off-by: Bodo Stroesser <bstroesser@ts.fujitsu.com> Signed-off-by: James Smart <james.smart@avagotech.com> Reviewed-by: Sebastian Herbszt <herbszt@gmx.de> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Firo Yang [Mon, 31 Aug 2015 20:48:09 +0000 (16:48 -0400)]
lpfc: Remove unnessary cast
kzalloc() returns a void pointer - no need to cast it in
drivers/scsi/lpfc/lpfc_init.c::lpfc_sli_driver_resource_setup()
Signed-off-by: Firo Yang <firogm@gmail.com> Signed-off-by: James Smart <james.smart@avagotech.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Signed-off-by: Sebastian Herbszt <herbszt@gmx.de> Signed-off-by: James Smart <james.smart@avagotech.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
3w controller don't dma map small single SGL entry commands but instead
bounce buffer them. Add a helper to identify these commands and don't
call scsi_dma_unmap for them.
Based on an earlier patch from James Bottomley.
Fixes: 118c85 ("3w-9xxx: fix command completion race") Reported-by: Tóth Attila <atoth@atoth.sote.hu> Tested-by: Tóth Attila <atoth@atoth.sote.hu> Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Adam Radford <aradford@gmail.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Paul Mackerras [Sat, 26 Sep 2015 00:19:15 +0000 (10:19 +1000)]
scsi_dh: Use the correct module name when loading device handler
This fixes a bug in recent kernels which results in failure to boot
on systems that have multipath SCSI disks. I observed this failure
on a POWER8 server where all the disks are multipath SCSI disks.
The symptoms are several messages like this on the console:
and the system does not find its disks, and therefore fails to boot.
Bisection revealed that the bug was introduced in commit 566079c849cf,
"dm-mpath, scsi_dh: request scsi_dh modules in scsi_dh, not dm-mpath".
The specific reason for the failure is that where we previously loaded
the "scsi_dh_alua" module, we are now trying to load the "alua" module,
which doesn't exist.
To fix this, we change the request_module call in scsi_dh_lookup()
to prepend "scsi_dh_" to the name, just like the old code in
drivers/md/dm-mpath.c:parse_hw_handler() used to do.
[jejb: also fixes issue spotted by Sasha Levin that formatting
characters could be passed in via sysfs and cause issues with
request_module()]
Fixes: 566079c849cf Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Cc: Sasha Levin <sasha.levin@oracle.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: James Bottomley <JBottomley@Odin.com>
libiscsi: Fix iscsi_check_transport_timeouts possible infinite loop
Connection last_ping is not being updated when iscsi_send_nopout fails.
Not updating the last_ping will cause firing a timer to a past time
(last_ping + ping_tmo < current_time) which triggers an infinite loop of
iscsi_check_transport_timeouts() and hogs the cpu.
Fix this issue by checking the return value of iscsi_send_nopout.
If it fails set the next_timeout to one second later.
Signed-off-by: Ariel Nahum <arieln@mellanox.com> Signed-off-by: Sagi Grimberg <sagig@mellanox.com> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Merge tag 'cris-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jesper/cris
Pull CRIS updates from Jesper Nilsson:
"Mostly removal of old cruft of which we can use a generic version, or
fixes for code not commonly run in the cris port, but also additions
to enable some good debug"
* tag 'cris-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jesper/cris: (25 commits)
CRISv10: delete unused lib/dmacopy.c
CRISv10: delete unused lib/old_checksum.c
CRIS: fix switch_mm() lockdep splat
CRISv32: enable LOCKDEP_SUPPORT
CRIS: add STACKTRACE_SUPPORT
CRISv32: annotate irq enable in idle loop
CRISv32: add support for irqflags tracing
CRIS: UAPI: use generic types.h
CRIS: UAPI: use generic shmbuf.h
CRIS: UAPI: use generic msgbuf.h
CRIS: UAPI: use generic socket.h
CRIS: UAPI: use generic sembuf.h
CRIS: UAPI: use generic sockios.h
CRIS: UAPI: use generic auxvec.h
CRIS: UAPI: use generic headers via Kbuild
CRIS: UAPI: fix elf.h export
CRIS: don't make asm/elf.h depend on asm/user.h
CRIS: UAPI: fix ptrace.h
CRISv32: Squash compile warnings for axisflashmap
CRISv32: Add GPIO driver to the default configs
...
Linus Torvalds [Wed, 27 May 2015 22:32:15 +0000 (15:32 -0700)]
blk: rq_data_dir() should not return a boolean
rq_data_dir() returns either READ or WRITE (0 == READ, 1 == WRITE), not
a boolean value.
Now, admittedly the "!= 0" doesn't really change the value (0 stays as
zero, 1 stays as one), but it's not only redundant, it confuses gcc, and
causes gcc to warn about the construct
switch (rq_data_dir(req)) {
case READ:
...
case WRITE:
...
that we have in a few drivers.
Now, the gcc warning is silly and stupid (it seems to warn not about the
switch value having a different type from the case statements, but about
_any_ boolean switch value), but in this case the code itself is silly
and stupid too, so let's just change it, and get rid of warnings like
this:
drivers/block/hd.c: In function ‘hd_request’:
drivers/block/hd.c:630:11: warning: switch condition has boolean value [-Wswitch-bool]
switch (rq_data_dir(req)) {
The odd '!= 0' came in when "cmd_flags" got turned into a "u64" in
commit 5953316dbf90 ("block: make rq->cmd_flags be 64-bit") and is
presumably because the old code (that just did a logical 'and' with 1)
would then end up making the type of rq_data_dir() be u64 too.
But if we want to retain the old regular integer type, let's just cast
the result to 'int' rather than use that rather odd '!= 0'.
Fix up the writeback plugging introduced in commit d353d7587d02
("writeback: plug writeback at a high level") that then caused problems
due to the unplug happening with a spinlock held.
* writeback-plugging:
writeback: plug writeback in wb_writeback() and writeback_inodes_wb()
Revert "writeback: plug writeback at a high level"
writeback: plug writeback in wb_writeback() and writeback_inodes_wb()
We had to revert the pluggin in writeback_sb_inodes() because the
wb->list_lock is held, but we could easily plug at a higher level before
taking that lock, and unplug after releasing it. This does that.
Chris will run performance numbers, just to verify that this approach is
comparable to the alternative (we could just drop and re-take the lock
around the blk_finish_plug() rather than these two commits.
I'd have preferred waiting for actual performance numbers before picking
one approach over the other, but I don't want to release rc1 with the
known "sleeping function called from invalid context" issue, so I'll
pick this cleanup version for now. But if the numbers show that we
really want to plug just at the writeback_sb_inodes() level, and we
should just play ugly games with the spinlock, we'll switch to that.
Cc: Chris Mason <clm@fb.com> Cc: Josef Bacik <jbacik@fb.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Neil Brown <neilb@suse.de> Cc: Jan Kara <jack@suse.cz> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I didn't notice this when merging the thermal code from Zhang, but his
merge (commit 5a924a07f882: "Merge branches 'thermal-core' and
'thermal-intel' of .git into next") of the thermal-core and
thermal-intel branches was wrong.
In thermal-core, commit 17e8351a7739 ("thermal: consistently use int for
temperatures") converted the thermal layer to use "int" for
temperatures.
But in parallel, in the thermal-intel branch commit d0a12625d2ff
("thermal: Add Intel PCH thermal driver") added support for the intel
PCH thermal sensor using the old interfaces that used "unsigned long"
pointers.
This resulted in warnings like this:
drivers/thermal/intel_pch_thermal.c:184:14: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types]
.get_temp = pch_thermal_get_temp,
^
drivers/thermal/intel_pch_thermal.c:184:14: note: (near initialization for ‘tzd_ops.get_temp’)
drivers/thermal/intel_pch_thermal.c:186:19: warning: initialization from incompatible pointer type [-Wincompatible-pointer-types]
.get_trip_temp = pch_get_trip_temp,
^
drivers/thermal/intel_pch_thermal.c:186:19: note: (near initialization for ‘tzd_ops.get_trip_temp’)
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
revert "ocfs2/dlm: use list_for_each_entry instead of list_for_each"
mm/early_ioremap: add explicit #include of asm/early_ioremap.h
fs/seq_file: convert int seq_vprint/seq_printf/etc... returns to void
selftests: enhance membarrier syscall test
selftests: add membarrier syscall test
sys_membarrier(): system-wide memory barrier (generic, x86)
MODSIGN: fix a compilation warning in extract-cert
Merge tag 'ntb-4.3' of git://github.com/jonmason/ntb
Pull NTB fixes from Jon Mason:
"NTB bug and documentation fixes, new device IDs, performance
improvements, and adding a mailing list to MAINTAINERS for NTB"
* tag 'ntb-4.3' of git://github.com/jonmason/ntb:
NTB: Fix range check on memory window index
NTB: Improve index handling in B2B MW workaround
NTB: Fix documentation for ntb_peer_db_clear.
NTB: Fix documentation for ntb_link_is_up
NTB: Use unique DMA channels for TX and RX
NTB: Remove dma_sync_wait from ntb_async_rx
NTB: Clean up QP stats info
NTB: Make the transport list in order of discovery
NTB: Add PCI Device IDs for Broadwell Xeon
NTB: Add flow control to the ntb_netdev
NTB: Add list to MAINTAINERS
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input
Pull more input updates from Dmitry Torokhov:
"Second round of updates for the input subsystem.
This introduces two brand new touchscreen drivers (Colibri and
imx6ul_tsc), some small driver fixes, and we are no longer report
errors from evdev_flush() as users do not really have a way of
handling errors, error codes that we were returning were not on the
list of errors supposed to be returned by close(), and errors were
causing issues with one of older versions of systemd"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: imx_keypad - remove obsolete comment
Input: touchscreen - add imx6ul_tsc driver support
Input: Add touchscreen support for Colibri VF50
Input: i8042 - lower log level for "no controller" message
Input: evdev - do not report errors form flush()
Input: elants_i2c - extend the calibration timeout to 12 seconds
Input: sparcspkr - fix module autoload for OF platform drivers
Input: regulator-haptic - fix module autoload for OF platform driver
Input: pwm-beeper - fix module autoload for OF platform driver
Input: ab8500-ponkey - Fix module autoload for OF platform driver
Input: cyttsp - remove unnecessary MODULE_ALIAS()
Input: elan_i2c - add ACPI ID "ELAN1000"
Merge tag 'pm+acpi-4.3-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more power management and ACPI updates from Rafael Wysocki:
"These are mostly fixes and cleanups on top of the previous PM+ACPI
pull request (cpufreq core and drivers, cpuidle, generic power domains
framework). Some of them didn't make to that pull request and some
fix issues introduced by it.
The only really new thing is the support for suspend frequency in the
cpufreq-dt driver, but it is needed to fix an issue with Exynos
platforms.
Specifics:
- build fix for the new Mediatek MT8173 cpufreq driver (Guenter
Roeck).
- generic power domains framework fixes (power on error code path,
subdomain removal) and cleanup of a deprecated API user (Geert
Uytterhoeven, Jon Hunter, Ulf Hansson).
- cpufreq-dt driver fixes including two fixes for bugs related to the
new Operating Performance Points Device Tree bindings introduced
recently (Viresh Kumar).
- suspend frequency support for the cpufreq-dt driver (Bartlomiej
Zolnierkiewicz, Viresh Kumar).
- cpufreq core cleanups (Viresh Kumar).
- intel_pstate driver fixes (Chen Yu, Kristen Carlson Accardi).
- additional sanity check in the cpuidle core (Xunlei Pang).
- fix for a comment related to CPU power management (Lina Iyer)"
* tag 'pm+acpi-4.3-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
intel_pstate: fix PCT_TO_HWP macro
intel_pstate: Fix user input of min/max to legal policy region
PM / OPP: Return suspend_opp only if it is enabled
cpufreq-dt: add suspend frequency support
cpufreq: allow cpufreq_generic_suspend() to work without suspend frequency
PM / OPP: add dev_pm_opp_get_suspend_opp() helper
staging: board: Migrate away from __pm_genpd_name_add_device()
cpufreq: Use __func__ to print function's name
cpufreq: staticize cpufreq_cpu_get_raw()
PM / Domains: Ensure subdomain is not in use before removing
cpufreq: Add ARM_MT8173_CPUFREQ dependency on THERMAL
cpuidle/coupled: Add sanity check for safe_state_index
PM / Domains: Try power off masters in error path of __pm_genpd_poweron()
cpufreq: dt: Tolerance applies on both sides of target voltage
cpufreq: dt: Print error on failing to mark OPPs as shared
cpufreq: dt: Check OPP count before marking them shared
kernel/cpu_pm: fix cpu_cluster_pm_exit comment
Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull second round of SCSI updates from James Bottomley:
"There's one late arriving patch here (added today), fixing a build
issue which the scsi_dh patch set in here uncovered. Other than that,
everything has been incubated in -next and the checkers for a week.
The major pieces of this patch are a set patches facilitating better
integration between scsi and scsi_dh (the device handling layer used
by multi-path; all the dm parts are acked by Mike Snitzer).
This also includes driver updates for mp3sas, scsi_debug and an
assortment of bug fixes"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (50 commits)
scsi_dh: fix randconfig build error
scsi: fix scsi_error_handler vs. scsi_host_dev_release race
fcoe: Convert use of __constant_htons to htons
mpt2sas: setpci reset kernel oops fix
pm80xx: Don't override ts->stat on IO_OPEN_CNX_ERROR_HW_RESOURCE_BUSY
lpfc: Fix possible use-after-free and double free in lpfc_mbx_cmpl_rdp_page_a2()
bfa: Fix incorrect de-reference of pointer
bfa: Fix indentation
scsi_transport_sas: Remove check for SAS expander when querying bay/enclosure IDs.
scsi_debug: resp_request: remove unused variable
scsi_debug: fix REPORT LUNS Well Known LU
scsi_debug: schedule_resp fix input variable check
scsi_debug: make dump_sector static
scsi_debug: vfree is null safe so drop the check
scsi_debug: use SCSI_W_LUN_REPORT_LUNS instead of SAM2_WLUN_REPORT_LUNS;
scsi_debug: define pr_fmt() for consistent logging
mpt2sas: Refcount fw_events and fix unsafe list usage
mpt2sas: Refcount sas_device objects and fix unsafe list usage
scsi_dh: return SCSI_DH_NOTCONN in scsi_dh_activate()
scsi_dh: don't allow to detach device handlers at runtime
...
Merge tag 'media/v4.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab:
"A series of patches that move part of the code used to allocate memory
from the media subsystem to the mm subsystem"
[ The mm parts have been acked by VM people, and the series was
apparently in -mm for a while - Linus ]
* tag 'media/v4.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
[media] drm/exynos: Convert g2d_userptr_get_dma_addr() to use get_vaddr_frames()
[media] media: vb2: Remove unused functions
[media] media: vb2: Convert vb2_dc_get_userptr() to use frame vector
[media] media: vb2: Convert vb2_vmalloc_get_userptr() to use frame vector
[media] media: vb2: Convert vb2_dma_sg_get_userptr() to use frame vector
[media] vb2: Provide helpers for mapping virtual addresses
[media] media: omap_vout: Convert omap_vout_uservirt_to_phys() to use get_vaddr_pfns()
[media] mm: Provide new get_vaddr_frames() helper
[media] vb2: Push mmap_sem down to memops
Merge tag 'edac/v4.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-edac
Pull edac updates from Mauro Carvalho Chehab:
"Two EDAC fixes for Intel systems (Haswell and Ivy Bridge)"
* tag 'edac/v4.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-edac:
sb_edac: correctly fetch DIMM width on Ivy Bridge and Haswell
sb_edac: look harder for DDRIO on Haswell systems
Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux
Pull thermal updates from Zhang Rui:
- use int instead of unsigned long to represent temperature to avoid
bogus overheat detection when negative temperature reported. From
Sascha Hauer.
- export available thermal governors information to user space via
sysfs. From Wei Ni.
- introduce new thermal driver for Wildcat Point platform controller
hub, which uses PCH thermal sensor and associated critical and hot
trip points. From Tushar Dave.
- add suuport for Intel Skylake and Denlow platforms in powerclamp
driver.
- some small cleanups in thermal core.
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/rzhang/linux:
thermal: Add Intel PCH thermal driver
thermal: Add comment explaining test for critical temperature
thermal: Use IS_ENABLED instead of #ifdef
thermal: remove unnecessary call to thermal_zone_device_set_polling
thermal: trivial: fix typo in comment
thermal: consistently use int for temperatures
thermal: add available policies sysfs attribute
thermal/powerclamp: add cpu id for denlow platform
thermal/powerclamp: add cpu id for Skylake u/y
thermal/powerclamp: add cpu id for skylake h/s
mm/early_ioremap: add explicit #include of asm/early_ioremap.h
Commit 6b0f68e32ea8 ("mm: add utility for early copy from unmapped ram")
introduces a function copy_from_early_mem() into mm/early_ioremap.c
which itself calls early_memremap()/early_memunmap(). However, since
early_memunmap() has not been declared yet at this point in the .c file,
nor by any explicitly included header files, we are depending on a
transitive include of asm/early_ioremap.h to declare it, which is
fragile.
So instead, include this header explicitly.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Mark Salter <msalter@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Joe Perches [Fri, 11 Sep 2015 20:07:48 +0000 (13:07 -0700)]
fs/seq_file: convert int seq_vprint/seq_printf/etc... returns to void
The seq_<foo> function return values were frequently misused.
See: commit 1f33c41c03da ("seq_file: Rename seq_overflow() to
seq_has_overflowed() and make public")
All uses of these return values have been removed, so convert the
return types to void.
Miscellanea:
o Move seq_put_decimal_<type> and seq_escape prototypes closer the
other seq_vprintf prototypes
o Reorder seq_putc and seq_puts to return early on overflow
o Add argument names to seq_vprintf and seq_printf
o Update the seq_escape kernel-doc
o Convert a couple of leading spaces to tabs in seq_escape
Signed-off-by: Joe Perches <joe@perches.com> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Mark Brown <broonie@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Joerg Roedel <jroedel@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Update the membarrier syscall self-test to match the membarrier
interface. Extend coverage of the interface. Consider ENOSYS as a
"SKIP" test, since it is a valid configuration, but does not allow
testing the system call.
Here is an implementation of a new system call, sys_membarrier(), which
executes a memory barrier on all threads running on the system. It is
implemented by calling synchronize_sched(). It can be used to
distribute the cost of user-space memory barriers asymmetrically by
transforming pairs of memory barriers into pairs consisting of
sys_membarrier() and a compiler barrier. For synchronization primitives
that distinguish between read-side and write-side (e.g. userspace RCU
[1], rwlocks), the read-side can be accelerated significantly by moving
the bulk of the memory barrier overhead to the write-side.
The existing applications of which I am aware that would be improved by
this system call are as follows:
* Through Userspace RCU library (http://urcu.so)
- DNS server (Knot DNS) https://www.knot-dns.cz/
- Network sniffer (http://netsniff-ng.org/)
- Distributed object storage (https://sheepdog.github.io/sheepdog/)
- User-space tracing (http://lttng.org)
- Network storage system (https://www.gluster.org/)
- Virtual routers (https://events.linuxfoundation.org/sites/events/files/slides/DPDK_RCU_0MQ.pdf)
- Financial software (https://lkml.org/lkml/2015/3/23/189)
Those projects use RCU in userspace to increase read-side speed and
scalability compared to locking. Especially in the case of RCU used by
libraries, sys_membarrier can speed up the read-side by moving the bulk of
the memory barrier cost to synchronize_rcu().
* Direct users of sys_membarrier
- core dotnet garbage collector (https://github.com/dotnet/coreclr/issues/198)
Microsoft core dotnet GC developers are planning to use the mprotect()
side-effect of issuing memory barriers through IPIs as a way to implement
Windows FlushProcessWriteBuffers() on Linux. They are referring to
sys_membarrier in their github thread, specifically stating that
sys_membarrier() is what they are looking for.
To explain the benefit of this scheme, let's introduce two example threads:
Thread A (non-frequent, e.g. executing liburcu synchronize_rcu())
Thread B (frequent, e.g. executing liburcu
rcu_read_lock()/rcu_read_unlock())
In a scheme where all smp_mb() in thread A are ordering memory accesses
with respect to smp_mb() present in Thread B, we can change each
smp_mb() within Thread A into calls to sys_membarrier() and each
smp_mb() within Thread B into compiler barriers "barrier()".
Before the change, we had, for each smp_mb() pairs:
Thread A Thread B
previous mem accesses previous mem accesses
smp_mb() smp_mb()
following mem accesses following mem accesses
After the change, these pairs become:
Thread A Thread B
prev mem accesses prev mem accesses
sys_membarrier() barrier()
follow mem accesses follow mem accesses
As we can see, there are two possible scenarios: either Thread B memory
accesses do not happen concurrently with Thread A accesses (1), or they
do (2).
1) Non-concurrent Thread A vs Thread B accesses:
Thread A Thread B
prev mem accesses
sys_membarrier()
follow mem accesses
prev mem accesses
barrier()
follow mem accesses
In this case, thread B accesses will be weakly ordered. This is OK,
because at that point, thread A is not particularly interested in
ordering them with respect to its own accesses.
2) Concurrent Thread A vs Thread B accesses
Thread A Thread B
prev mem accesses prev mem accesses
sys_membarrier() barrier()
follow mem accesses follow mem accesses
In this case, thread B accesses, which are ensured to be in program
order thanks to the compiler barrier, will be "upgraded" to full
smp_mb() by synchronize_sched().
* Benchmarks
On Intel Xeon E5405 (8 cores)
(one thread is calling sys_membarrier, the other 7 threads are busy
looping)
1000 non-expedited sys_membarrier calls in 33s =3D 33 milliseconds/call.
* User-space user of this system call: Userspace RCU library
Both the signal-based and the sys_membarrier userspace RCU schemes
permit us to remove the memory barrier from the userspace RCU
rcu_read_lock() and rcu_read_unlock() primitives, thus significantly
accelerating them. These memory barriers are replaced by compiler
barriers on the read-side, and all matching memory barriers on the
write-side are turned into an invocation of a memory barrier on all
active threads in the process. By letting the kernel perform this
synchronization rather than dumbly sending a signal to every process
threads (as we currently do), we diminish the number of unnecessary wake
ups and only issue the memory barriers on active threads. Non-running
threads do not need to execute such barrier anyway, because these are
implied by the scheduler context switches.
The dynamic sys_membarrier availability check adds some overhead to
the read-side compared to the signal-based scheme, but besides that,
sys_membarrier slightly outperforms the signal-based scheme. However,
this non-expedited sys_membarrier implementation has a much slower grace
period than signal and memory barrier schemes.
Besides diminishing the number of wake-ups, one major advantage of the
membarrier system call over the signal-based scheme is that it does not
need to reserve a signal. This plays much more nicely with libraries,
and with processes injected into for tracing purposes, for which we
cannot expect that signals will be unused by the application.
An expedited version of this system call can be added later on to speed
up the grace period. Its implementation will likely depend on reading
the cpu_curr()->mm without holding each CPU's rq lock.
This patch adds the system call to x86 and to asm-generic.
[1] http://urcu.so
membarrier(2) man page:
MEMBARRIER(2) Linux Programmer's Manual MEMBARRIER(2)
NAME
membarrier - issue memory barriers on a set of threads
SYNOPSIS
#include <linux/membarrier.h>
int membarrier(int cmd, int flags);
DESCRIPTION
The cmd argument is one of the following:
MEMBARRIER_CMD_QUERY
Query the set of supported commands. It returns a bitmask of
supported commands.
MEMBARRIER_CMD_SHARED
Execute a memory barrier on all threads running on the system.
Upon return from system call, the caller thread is ensured that
all running threads have passed through a state where all memory
accesses to user-space addresses match program order between
entry to and return from the system call (non-running threads
are de facto in such a state). This covers threads from all pro=E2=80=90
cesses running on the system. This command returns 0.
The flags argument needs to be 0. For future extensions.
All memory accesses performed in program order from each targeted
thread is guaranteed to be ordered with respect to sys_membarrier(). If
we use the semantic "barrier()" to represent a compiler barrier forcing
memory accesses to be performed in program order across the barrier,
and smp_mb() to represent explicit memory barriers forcing full memory
ordering across the barrier, we have the following ordering table for
each pair of barrier(), sys_membarrier() and smp_mb():
The pair ordering is detailed as (O: ordered, X: not ordered):
barrier() smp_mb() sys_membarrier()
barrier() X X O
smp_mb() X O O
sys_membarrier() O O O
RETURN VALUE
On success, these system calls return zero. On error, -1 is returned,
and errno is set appropriately. For a given command, with flags
argument set to 0, this system call is guaranteed to always return the
same value until reboot.
ERRORS
ENOSYS System call is not implemented.
EINVAL Invalid arguments.
Linux 2015-04-15 MEMBARRIER(2)
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Nicholas Miell <nmiell@comcast.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Cc: Lai Jiangshan <laijs@cn.fujitsu.com> Cc: Stephen Hemminger <stephen@networkplumber.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: David Howells <dhowells@redhat.com> Cc: Pranith Kumar <bobby.prani@gmail.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Shuah Khan <shuahkh@osg.samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
David Howells [Fri, 11 Sep 2015 20:07:36 +0000 (13:07 -0700)]
MODSIGN: fix a compilation warning in extract-cert
Fix the following warning when compiling extract-cert:
scripts/extract-cert.c: In function `write_cert':
scripts/extract-cert.c:89:2: warning: format not a string literal and no format arguments [-Wformat-security]
ERR(!i2d_X509_bio(wb, x509), cert_dst);
^
whereby the ERR() macro is taking cert_dst as the format string. "%s"
should be used as the format string as the path could contain special
characters.
Signed-off-by: David Howells <dhowells@redhat.com> Reported-by: Jim Davis <jim.epost@gmail.com>
Acked-by : David Woodhouse <david.woodhouse@intel.com> Cc: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull watchdog updates from Wim Van Sebroeck:
- new driver for NXP LPC18xx Watchdog Timer
- new driver for SAMA5D4 watchdog timer
- add support for MCP79 to nv_tco driver
- clean-up and improvement of the mpc8xxx watchdog driver
- improvements to gpio-wdt
- at91sam9_wdt clock improvements
... and other small fixes and improvements
* git://www.linux-watchdog.org/linux-watchdog: (25 commits)
Watchdog: Fix parent of watchdog_devices
watchdog: at91rm9200: Correct check for syscon_node_to_regmap() errors
watchdog: at91sam9: get and use slow clock
Documentation: dt: binding: atmel-sama5d4-wdt: for SAMA5D4 watchdog driver
watchdog: add a driver to support SAMA5D4 watchdog timer
watchdog: mpc8xxx: allow to compile for MPC512x
watchdog: mpc8xxx: use better error code when watchdog cannot be enabled
watchdog: mpc8xxx: use dynamic memory for device specific data
watchdog: mpc8xxx: use devm_ioremap_resource to map memory
watchdog: mpc8xxx: make use of of_device_get_match_data
watchdog: mpc8xxx: simplify registration
watchdog: mpc8xxx: remove dead code
watchdog: lpc18xx_wdt_get_timeleft() can be static
DT: watchdog: Add NXP LPC18xx Watchdog Timer binding documentation
watchdog: NXP LPC18xx Watchdog Timer Driver
watchdog: gpio-wdt: ping already at startup for always running devices
watchdog: gpio-wdt: be more strict about hw_algo matching
Documentation: watchdog: at91sam9_wdt: add clocks property
watchdog: booke_wdt: Use infrastructure to check timeout limits
watchdog: (nv_tco) add support for MCP79
...
Doing the block layer plug/unplug inside writeback_sb_inodes() is
broken, because that function is actually called with a spinlock held:
wb->list_lock, as pointed out by Chris Mason.
Chris suggested just dropping and re-taking the spinlock around the
blk_finish_plug() call (the plgging itself can happen under the
spinlock), and that would technically work, but is just disgusting.
We do something fairly similar - but not quite as disgusting because we
at least have a better reason for it - in writeback_single_inode(), so
it's not like the caller can depend on the lock being held over the
call, but in this case there just isn't any good reason for that
"release and re-take the lock" pattern.
[ In general, we should really strive to avoid the "release and retake"
pattern for locks, because in the general case it can easily cause
subtle bugs when the caller caches any state around the call that
might be invalidated by dropping the lock even just temporarily. ]
But in this case, the plugging should be easy to just move up to the
callers before the spinlock is taken, which should even improve the
effectiveness of the plug. So there is really no good reason to play
games with locking here.
I'll send off a test-patch so that Dave Chinner can verify that that
plug movement works. In the meantime this just reverts the problematic
commit and adds a comment to the function so that we hopefully don't
make this mistake again.
Reported-by: Chris Mason <clm@fb.com> Cc: Josef Bacik <jbacik@fb.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Neil Brown <neilb@suse.de> Cc: Jan Kara <jack@suse.cz> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge branch 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs
Pull btrfs cleanups and fixes from Chris Mason:
"These are small cleanups, and also some fixes for our async worker
thread initialization.
I was having some trouble testing these, but it ended up being a
combination of changing around my test servers and a shiny new
schedule while atomic from the new start/finish_plug in
writeback_sb_inodes().
That one only hits on btrfs raid5/6 or MD raid10, and if I wasn't
changing a bunch of things in my test setup at once it would have been
really clear. Fix for writeback_sb_inodes() on the way as well"
* 'for-linus-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: cleanup: remove unnecessary check before btrfs_free_path is called
btrfs: async_thread: Fix workqueue 'max_active' value when initializing
btrfs: Add raid56 support for updating num_tolerated_disk_barrier_failures in btrfs_balance
btrfs: Cleanup for btrfs_calc_num_tolerated_disk_barrier_failures
btrfs: Remove noused chunk_tree and chunk_objectid from scrub_enumerate_chunks and scrub_chunk
btrfs: Update out-of-date "skip parity stripe" comment
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client
Pull Ceph update from Sage Weil:
"There are a few fixes for snapshot behavior with CephFS and support
for the new keepalive protocol from Zheng, a libceph fix that affects
both RBD and CephFS, a few bug fixes and cleanups for RBD from Ilya,
and several small fixes and cleanups from Jianpeng and others"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
ceph: improve readahead for file holes
ceph: get inode size for each append write
libceph: check data_len in ->alloc_msg()
libceph: use keepalive2 to verify the mon session is alive
rbd: plug rbd_dev->header.object_prefix memory leak
rbd: fix double free on rbd_dev->header_name
libceph: set 'exists' flag for newly up osd
ceph: cleanup use of ceph_msg_get
ceph: no need to get parent inode in ceph_open
ceph: remove the useless judgement
ceph: remove redundant test of head->safe and silence static analysis warnings
ceph: fix queuing inode to mdsdir's snaprealm
libceph: rename con_work() to ceph_con_workfn()
libceph: Avoid holding the zero page on ceph_msgr_slab_init errors
libceph: remove the unused macro AES_KEY_SIZE
ceph: invalidate dirty pages after forced umount
ceph: EIO all operations after forced umount
Merge tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull GFS2 updates from Bob Peterson:
"Here is a list of patches we've accumulated for GFS2 for the current
upstream merge window. This time we've only got six patches, many of
which are very small:
- three cleanups from Andreas Gruenbacher, including a nice cleanup
of the sequence file code for the sbstats debugfs file.
- a patch from Ben Hutchings that changes statistics variables from
signed to unsigned.
- two patches from me that increase GFS2's glock scalability by
switching from a conventional hash table to rhashtable"
* tag 'gfs2-merge-window' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
gfs2: A minor "sbstats" cleanup
gfs2: Fix a typo in a comment
gfs2: Make statistics unsigned, suitable for use with do_div()
GFS2: Use resizable hash table for glocks
GFS2: Move glock superblock pointer to field gl_name
gfs2: Simplify the seq file code for "sbstats"
It looks like the Kconfig check that was meant to fix this (commit fe9233fb6914a0eb20166c967e3020f7f0fba2c9 [SCSI] scsi_dh: fix kconfig related
build errors) was actually reversed, but no-one noticed until the new set of
patches which separated DM and SCSI_DH).
Fixes: fe9233fb6914a0eb20166c967e3020f7f0fba2c9 Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
Merge tag 'sound-fix-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound
Pull sound fixes from Takashi Iwai:
"A collection of small fixes since the last update: the HD-audio quirks
as usual with a USB-audio fix and a trivial fix for the old sparc
driver"
* tag 'sound-fix-4.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
ALSA: usb-audio: Change internal PCM order
ALSA: hda - Fix white noise on Dell M3800
ALSA: hda - Use ALC880_FIXUP_FUJITSU for FSC Amilo M1437
ALSA: hda - Enable headphone jack detect on old Fujitsu laptops
ALSA: sparc: amd7930: Fix module autoload for OF platform driver
ALSA: hda - Add some FIXUP quirks for white noise on Dell laptop.
Merge branch 'drm-fixes' of git://people.freedesktop.org/~airlied/linux
Pull drm fixes from Dave Airlie:
"Just a bunch of fixes to squeeze in before -rc1:
- three nouveau regression fixes
- one qxl regression fix
- a bunch of i915 fixes
... and some core displayport/atomic fixes"
* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
drm/nouveau/device: enable c800 quirk for tecra w50
drm/nouveau/clk/gt215: Unbreak engine pausing for GT21x/MCP7x
drm/nouveau/gr/nv04: fix big endian setting on gr context
drm/qxl: validate monitors config modes
drm/i915: Allow DSI dual link to be configured on any pipe
drm/i915: Don't try to use DDR DVFS on CHV when disabled in the BIOS
drm/i915: Fix CSR MMIO address check
drm/i915: Limit the number of loops for reading a split 64bit register
drm/i915: Fix broken mst get_hw_state.
drm/i915: Pass hpd_status_i915[] to intel_get_hpd_pins() in pre-g4x
uapi/drm/i915_drm.h: fix userspace compilation.
drm/i915: Always mark the object as dirty when used by the GPU
drm/dp: Add dp_aux_i2c_speed_khz module param to set the assume i2c bus speed
drm/dp: Adjust i2c-over-aux retry count based on message size and i2c bus speed
drm/dp: Define AUX_RETRY_INTERVAL as 500 us
drm/atomic: Fix bookkeeping with TEST_ONLY, v3.
* pm-cpuidle:
cpuidle/coupled: Add sanity check for safe_state_index
* pm-domains:
staging: board: Migrate away from __pm_genpd_name_add_device()
PM / Domains: Ensure subdomain is not in use before removing
PM / Domains: Try power off masters in error path of __pm_genpd_poweron()
* pm-cpufreq:
intel_pstate: fix PCT_TO_HWP macro
intel_pstate: Fix user input of min/max to legal policy region
cpufreq-dt: add suspend frequency support
cpufreq: allow cpufreq_generic_suspend() to work without suspend frequency
cpufreq: Use __func__ to print function's name
cpufreq: staticize cpufreq_cpu_get_raw()
cpufreq: Add ARM_MT8173_CPUFREQ dependency on THERMAL
cpufreq: dt: Tolerance applies on both sides of target voltage
cpufreq: dt: Print error on failing to mark OPPs as shared
cpufreq: dt: Check OPP count before marking them shared
Andy Grover [Thu, 3 Sep 2015 23:03:43 +0000 (16:03 -0700)]
target: Remove no-op conditional
This does nothing, and there are many other places where
transport_cmd_check_stop_to_fabric()'s retval is not checked>, If we
wanted to check it here, we should probably do it those other places too.
Signed-off-by: Andy Grover <agrover@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
projects / linux-beck.git / log