The sc_return_credits() function tests whether its argument is NULL
and then returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Per file descriptor TID caching actions depend on a global that can
change midway through the lifetime of that file descriptor.

Make the use of caching consistent for the life of the file descriptor
by using the presence of the cache handler to decide when to use the cache
functions.
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The hfi1 driver registers a mmu_notifier callback when /dev/hfi1_* is
opened, and unregisters it when the device is closed.  The driver
incorrectly assumes that the close will always happen from the same
context as the open.  In particular, closes due to SIGKILL or OOM killer
activity may happen from a different context.  In these cases, the wrong
mm is passed to mmu_notifier_unregister(), which causes improper reference
counting for the victim mm, and eventual memory corruption.

Preserve the mm for all open file descriptors and use this mm rather than
current->mm for memory operations for the lifetime of that fd.  Note: this
patch leaves 1 use of current->mm in place.  This use is removed in a
follow on patch because other functional changes were required prior to
that use being removed.

If registration fails, there is no reason to keep the handler object
around.  Free the handler object rather than add it to the list to
prevent any mmu_notifier operations, including unregister, when
registration fails.
Suggested-by: NJim Foraker <foraker1@llnl.gov>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Save the current capability state at user context creation
time.  Report this saved value for all shared contexts.

Also get rid of unnecessary hfi1_get_base_kinfo function.
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Rearrange the file open call in prep for new changes.
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

These are no longer needed.
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

When performing process affinity recommendations for MPI ranks, the current
algorithm doesn't take into account multiple HFI units. Also, real
cores and HT cores are not distinguished from one another. Therefore,
all HT cores are recommended to be assigned first within the local NUMA
node before recommending the assignments of cores in other NUMA nodes.
It's ideal to assign all real cores across all NUMA nodes first, then all
HT 1 cores, then all HT 2 cores, and so on to balance CPU workload. CPU
cores in other NUMA nodes could be running interrupt handlers, and this is
not taken into account.

To balance the CPU workload for user processes, the following
recommendation algorithm is used:

 For each user process that is opening a context on HFI Y:
  a) If all cores are assigned to user processes, start assignments all
	 over from the first core
  b) Assign real cores first, then HT cores (First set of HT cores on
	 all physical cores, then second set of HT cores, and, so on) in the
	 following order:

	 1. Same NUMA node as HFI Y and not running an IRQ handler
	 2. Same NUMA node as HFI Y and running an IRQ handler
	 3. Different NUMA node to HFI Y and not running an IRQ handler
	 4. Different NUMA node to HFI Y and running an IRQ handler
  c) Mark core as assigned in the global affinity structure. As user
	 processes are done, remove core assignments from global affinity
	 structure.

This implementation allows an arbitrary number of HT cores and provides
support for multiple HFIs.

This is being included in the kernel rather than user space due to the
fact that user space has no way of knowing the CPU recommendations for
contexts running as part of other jobs.
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NMitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NSebastian Sanchez <sebastian.sanchez@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Simple code clean up of hfi1_write_iter.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

If a context has already been assigned to an FD, prevent
another assignment.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The TODO list for the hfi1 driver was completed during 4.6. In addition
other objections raised (which are far beyond what was in the TODO list)
have been addressed as well. It is now time to remove the driver from
staging and into the drivers/infiniband sub-tree.
Reviewed-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The deletion of a cdev is not a fence for holding off references to the
structure. The driver attempts to delete the cdev and then proceeds to
free the parent structure, the hfi1_devdata, or dd. This can potentially
lead to a kernel panic in situations where a user has an FD for the cdev
open, and the pci device gets removed. If the user then closes the FD
there will be a NULL dereference when trying to do put on the cdev's
kobject.

Fix this by pointing the cdev's kobject.parent at a new kobject embedded
in its parent structure. Also take a reference when the device is opened
and put it back when it is closed.
Reviewed-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add a trace message to HFI1s user IOCTL handling. This allows debugging
of which IOCTLs are being handled by the driver.
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Remove the write() handler for user space commands now that ioctl
handling is available. User apps will need to change to use ioctl from
this point forward.
Reviewed-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

IOCTL is more suited to what user space commands need to do than the
write() interface. Add IOCTL definitions for all existing write commands
and the handling for those. The write() interface will be removed in a
follow on patch.
Reviewed-by: NMitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The HFI1_CMD_SDMA_STATUS_UPD command was never implemented it has no
reason to live in the driver. Remove it.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The snoop/diag interface is better served by an implementation which is
more general and usable by other drivers perhaps. Go ahead and remove
the code now and get rid of the char dev. We can put the feature back
when we have a more agreeable solution.
Reviewed-by: NDean Luick <dean.luick@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Remove EPROM handling from the cdev which is used for user application
data traffic.
Reviewed-by: NDean Luick <dean.luick@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Remove UI char device which exposes direct access to registers for user
space. This was put in to aid in debugging the hardware. We are looking
into alternatives means of providing the same functionality. This
removes another char device from HFI1's footprint.
Reviewed-by: NDean Luick <dean.luick@intel.com>
Reviewed-by: NMitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

hfi1 current exports a cdev that can be used to target all of the hfi's
in the system. However there is a problem with this approach in
that the devices could be on different subnets. This is a problem that
user space can figure out and explicitly tell the driver on which device
to create a context.

Remove the multi-purpose cdev leaving a dedicated cdev for each port.
Also remove the striping capability that is dependent upon the user
choosing the multi-purpose cdev. It is now up to user space to determine
how to stripe contexts.
Reviewed-by: NDean Luick <dean.luick@intel.com>
Reviewed-by: NMitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The drivers/infiniband stack uses write() as a replacement for
bi-directional ioctl().  This is not safe. There are ways to
trigger write calls that result in the return structure that
is normally written to user space being shunted off to user
specified kernel memory instead.

For the immediate repair, detect and deny suspicious accesses to
the write API.

For long term, update the user space libraries and the kernel API
to something that doesn't present the same security vulnerabilities
(likely a structured ioctl() interface).

The impacted uAPI interfaces are generally only available if
hardware from drivers/infiniband is installed in the system.
Reported-by: NJann Horn <jann@thejh.net>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NJason Gunthorpe <jgunthorpe@obsidianresearch.com>
[ Expanded check to all known write() entry points ]
Cc: stable@vger.kernel.org
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The ui device llseek had a mistake with SEEK_END and did
not fully follow seek semantics.  Correct all this by
using a kernel supplied function for fixed size devices.

Cc: Al Viro <viro@ZenIV.linux.org.uk>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Attempting to free resources which have not been allocated and
initialized properly led to the following kernel backtrace:

    BUG: unable to handle kernel NULL pointer dereference at           (null)
    IP: [<ffffffffa09658fe>] unlock_exp_tids.isra.8+0x2e/0x120 [hfi1]
    PGD 852a43067 PUD 85d4a6067 PMD 0
    Oops: 0000 [#1] SMP
    CPU: 0 PID: 2831 Comm: osu_bw Tainted: G          IO 3.12.18-wfr+ #1
    task: ffff88085b15b540 ti: ffff8808588fe000 task.ti: ffff8808588fe000
    RIP: 0010:[<ffffffffa09658fe>]  [<ffffffffa09658fe>] unlock_exp_tids.isra.8+0x2e/0x120 [hfi1]
    RSP: 0018:ffff8808588ffde0  EFLAGS: 00010282
    RAX: 0000000000000000 RBX: ffff880858a31800 RCX: 0000000000000000
    RDX: ffff88085d971bc0 RSI: ffff880858a318f8 RDI: ffff880858a318c0
    RBP: ffff8808588ffe20 R08: 0000000000000000 R09: 0000000000000000
    R10: ffff88087ffd6f40 R11: 0000000001100348 R12: ffff880852900000
    R13: ffff880858a318c0 R14: 0000000000000000 R15: ffff88085d971be8
    FS:  00007f4674e83740(0000) GS:ffff88087f400000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 0000000000000000 CR3: 000000085c377000 CR4: 00000000001407f0
    Stack:
     ffffffffa0941a71 ffff880858a318f8 ffff88085d971bc0 ffff880858a31800
     ffff880852900000 ffff880858a31800 00000000003ffff7 ffff88085d971bc0
     ffff8808588ffe60 ffffffffa09663fc ffff8808588ffe60 ffff880858a31800
    Call Trace:
     [<ffffffffa0941a71>] ? find_mmu_handler+0x51/0x70 [hfi1]
     [<ffffffffa09663fc>] hfi1_user_exp_rcv_free+0x6c/0x120 [hfi1]
     [<ffffffffa0932809>] hfi1_file_close+0x1a9/0x340 [hfi1]
     [<ffffffff8116c189>] __fput+0xe9/0x270
     [<ffffffff8116c35e>] ____fput+0xe/0x10
     [<ffffffff81065707>] task_work_run+0xa7/0xe0
     [<ffffffff81002969>] do_notify_resume+0x59/0x80
     [<ffffffff814ffc1a>] int_signal+0x12/0x17

This commit re-arranges the context initialization code in a way that
would allow for context event flags to be used to determine whether
the context has been successfully initialized.

In turn, this can be used to skip the resource de-allocation if they
were never allocated in the first place.

Fixes: 3abb33ac ("staging/hfi1: Add TID cache receive init and free funcs")
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com.
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The MMU notification code added to the
expected receive side has been re-factored and
split into it's own file. This was done in
order to make the code more general and, therefore,
usable by other parts of the driver.

The caching behavior remains the same. However,
the handling of the RB tree (insertion, deletions,
and searching) as well as the MMU invalidation
processing is now handled by functions in the
mmu_rb.[ch] files.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

mm.h contains a helper function PAGE_ALIGN which aligns the pointer
to the page boundary instead of using ALIGN(expression, PAGE_SIZE)

This change was made with the help of the following Coccinelle
semantic patch:
//<smpl>
@@
expression e;
symbol PAGE_SIZE;
@@
(
- ALIGN(e, PAGE_SIZE)
+ PAGE_ALIGN(e)
|
- IS_ALIGNED(e, PAGE_SIZE)
+ PAGE_ALIGNED(e)
)
//</smpl>
Signed-off-by: NAmitoj Kaur Chawla <amitoj1606@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Fix the header by moving the copyright notice out of the license text
and to the top of the header. Also, update the copyright date.
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Add braces on all arms of statements to fix checkpatch check:
CHECK: braces {} should be used on all arms of this statement
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Fix code alignment to fix checkpatch check:
CHECK: Alignment should match open parenthesis
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Fix block comments with proper formatting to fix checkpatch warnings:
WARNING: Block comments use * on subsequent lines
WARNING: Block comments use a trailing */ on a separate line
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Move logical continuations to previous line to fix checkpatch check:
CHECK: Logical continuations should be on the previous line
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Remove multiple blank lines to fix checkpatch check:
CHECK: Please don't use multiple blank lines
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

When writing to the EPROM, the driver will always use the
"first" device.  This is incorrect for multiple cards.

Use the device file minor to determine the device to use.
Reject the generic device file.
Reviewed-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NDean Luick <dean.luick@intel.com>
Signed-off-by: NJubin John <jubin.john@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Allocate the user mode send context memory on the numa node which the
device is attached to for better performance.
Reviewed-by: NDean Luick <dean.luick@intel.com>
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This patch unifies the affinity support for CPU and IRQ allocations into
a single code base. The goal is to allow the driver to make intelligent
placement decision based on an overall view of processes and IRQs across
as much of the driver as possible.

Pulling all the scattered affinity code into a single code base lays the
ground work for accomplishing the above goal.  For example, previous
implementations made user process placement decision solely based on
other user processes.  This algorithm is limited as it did not take into
account IRQ placement and could result in overloading certain CPUs.

A single code base also provides a much easier way to maintain and debug
any performance issues related to affinity.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

hfi1 HW has a high PCIe ASPM L1 exit latency and also advertises an
acceptable latency less than actual ASPM latencies. Additional
mechanisms than those provided by BIOS/OS are therefore required to
enable/disable ASPM for hfi1 to provide acceptable power/performance
trade offs. This patch adds this support.

By means of a module parameter ASPM can be either (a) always enabled
(power save mode) (b) always disabled (performance mode) (c)
enabled/disabled dynamically. The dynamic mode implements two
heuristics to alleviate possible problems with high ASPM L1 exit
latency. ASPM is normally enabled but is disabled if (a) there are any
active user space PSM contexts, or (b) for verbs, ASPM is disabled as
interrupt activity for a context starts to increase.

A few more points about the verbs implementation. In order to reduce
lock/cache contention between multiple verbs contexts, some processing
is done at the context layer before contending for device layer
locks. ASPM is disabled when two interrupts for a context happen
within 1 millisec. A timer is scheduled which will re-enable ASPM
after 1 second should the interrupt activity cease. Normally, every
interrupt, or interrupt-pair should push the timer out
further. However, since this might increase the processing load per
interrupt, pushing the timer out is postponed for half a second. If
after half a second we get two interrupts within 1 millisec the timer
is pushed out by another second.

Finally, the kernel ASPM API is not used in this patch. This is
because this patch does several non-standard things as SW workarounds
for HW issues. As mentioned above, it enables ASPM even when advertised
actual latencies are greater than acceptable latencies. Also, whereas
the kernel API only allows drivers to disable ASPM from driver probe,
this patch enables/disables ASPM directly from interrupt context. Due
to these reasons the kernel ASPM API was not used.
Reviewed-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: NDean Luick <dean.luick@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NAshutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The RcvCtxtCtrl register was being incorrectly set upon context
initialization and clean up resulting, in many cases, of contexts using
settings from previous contexts' initialization. This resulted in bad
and unexpected behavior. This was especially important for the TailUpd
bit, which requires special handling and if set incorrectly could lead
to severely degraded performance.

This patch fixes the handling of the RcvCtxtCtrl register, ensuring that
each context gets initialized with settings applicable only for that
context. It also ensures the proper setting for the TailUpd bit by
setting it to either 0 or 1 (as needed by the context's configuration)
explicitly.
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This commit "flips the switch" on the TID caching feature
implemented in this patch series.

As well as enabling the new feature by tying the new function
with the PSM API, it also cleans up the old unneeded code,
data structure members, and variables.

Due to difference in operation and information, the tracing
functions related to expected receives had to be changed. This
patch include these changes.

The tracing function changes could not be split into a separate
commit without including both tracing variants at the same time.
This would have caused other complications and ugliness.
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The exp_lock lock does not need to be a spinlock as
all its uses are in process context and allowing the
process to sleep when the mutex is contended might
be beneficial.
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

There is no need to use a separate variable for a
return value and a label when returning right away
would do just as well.
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

TID caching will use a new event to signal userland that cache
invalidation has occurred and needs a matching command code that
will be used to read the invalidated TIDs.

Add the event bit and the new command to the exported header file.

The command is also added to the switch() statement in file_ops.c
for completeness and in preparation for its usage later.
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Convert hfi1_get_user_pages() to use get_user_pages_fast(),
which is much fatster. The mm semaphore is still taken to
update the pinned page count but is for a much shorter
amount of time.
Reviewed-by: NIra Weiny <ira.weiny@intel.com>
Signed-off-by: NMitko Haralanov <mitko.haralanov@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>