Even if it works fine with those global variables, attaching the
temporary ech and vidh objects used during UBI scan to the
ubi_attach_info object sounds like a more future-proof option.

For example, attaching several UBI devices in parallel is prevented by
this use of global variable. And also because global variables should
be avoided in general.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

This not only hides the aeb allocation internals (which is always good in
case we ever want to change the allocation system), but also helps us
factorize the initialization of some common fields (ec and pnum).
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

ubi_io_{read,write}_data() are wrappers around ubi_io_{read/write}() that
are used to read/write eraseblock payload data, which is exactly what
fastmap does when calling ubi_io_{read,write}().
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Use the ubi_rb_for_each_entry() macro instead of open-coding it.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Those functions are pretty much doing the same thing, except
ubi_remove_av() is putting the aeb elements attached to the volume into
the ai->erase list and the destroy_av() is freeing them.

Rework destroy_av() to handle both cases.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Volume creation/search code is duplicated in a few places (fastmap and
non fastmap code). Create some helpers to factorize the code.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

vol->usable_size is already set to ubi->leb_size - vol->data_pad. Use
vol->usable_size instead of recalculating it.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

scan_pool() does not mark the PEB for scrubing when bitflips are
detected in the EC header of a free PEB (VID header region left to
0xff).
Make sure we scrub the PEB in this case.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Fixes: dbb7d2a8 ("UBI: Add fastmap core")
Signed-off-by: Richard Weinberger <richard@nod.at>

process_pool_aeb() does several times the be32_to_cpu(new_vh->vol_id)
operation. Create a temporary variable and do it once.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

add_fastmap() is passed a ubi_vid_hdr pointer in argument, but is
referencing the global vidh pointer.
Even if this is correct from a functional point of view (vidh and vid_hdr
point to the same object), it is confusing.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

process_pool_aeb() re-implements the logic found in ubi_find_volume().
Call ubi_find_volume() to avoid this duplication.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

Pull USB fixes from Greg KH:
 "Here are two small fixes, and one new device id, for 4.8-rc7

  The fixes solve a build error that was reported in your tree for the
  blackfin arch, and resolve an issue with a number of broken USB
  devices that reported the wrong interval rate.  Included here is also
  a new device id for the usb-serial driver.

  All have been in linux-next with no reported issues"

* tag 'usb-4.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  USB: change bInterval default to 10 ms
  usb: musb: Fix tusb6010 compile error on blackfin
  USB: serial: simple: add support for another Infineon flashloader

Merge tag 'fixes-for-linus-v4.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull uaccess fixes from Guenter Roeck:
 "Two patches fixing problems introduced with copy_from_user changes"

* tag 'fixes-for-linus-v4.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  openrisc: fix the fix of copy_from_user()
  avr32: fix 'undefined reference to `___copy_from_user'

Pull perf fixes from Thomas Gleixner:
 "A couple of small fixes to x86 perf drivers:

   - Measure L2 for HW_CACHE* events on AMD

   - Fix the address filter handling in the intel/pt driver

   - Handle the BTS disabling at the proper place"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/amd: Make HW_CACHE_REFERENCES and HW_CACHE_MISSES measure L2
  perf/x86/intel/pt: Do validate the size of a kernel address filter
  perf/x86/intel/pt: Fix kernel address filter's offset validation
  perf/x86/intel/pt: Fix an off-by-one in address filter configuration
  perf/x86/intel: Don't disable "intel_bts" around "intel" event batching

Pull SMP build fixlet from Thomas Gleixner:
 "Add a missing include in cpuhotplug.h"

* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  cpu/hotplug: Include linux/types.h in linux/cpuhotplug.h

Pull irq fixes from Thomas Gleixner:
 "Two patches from Boris which address a potential deadlock in the atmel
  irq chip driver"

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/atmel-aic: Fix potential deadlock in ->xlate()
  genirq: Provide irq_gc_{lock_irqsave,unlock_irqrestore}() helpers

Since commit acb2505d ("openrisc: fix copy_from_user()"),
copy_from_user() returns the number of bytes requested, not the
number of bytes not copied.

Cc: Al Viro <viro@zeniv.linux.org.uk>
Fixes: acb2505d ("openrisc: fix copy_from_user()")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

avr32 builds fail with:

arch/avr32/kernel/built-in.o: In function `arch_ptrace':
(.text+0x650): undefined reference to `___copy_from_user'
arch/avr32/kernel/built-in.o:(___ksymtab+___copy_from_user+0x0): undefined
reference to `___copy_from_user'
kernel/built-in.o: In function `proc_doulongvec_ms_jiffies_minmax':
(.text+0x5dd8): undefined reference to `___copy_from_user'
kernel/built-in.o: In function `proc_dointvec_minmax_sysadmin':
sysctl.c:(.text+0x6174): undefined reference to `___copy_from_user'
kernel/built-in.o: In function `ptrace_has_cap':
ptrace.c:(.text+0x69c0): undefined reference to `___copy_from_user'
kernel/built-in.o:ptrace.c:(.text+0x6b90): more undefined references to
`___copy_from_user' follow

Fixes: 8630c322 ("avr32: fix copy_from_user()")
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Havard Skinnemoen <hskinnemoen@gmail.com>
Acked-by: Hans-Christian Noren Egtvedt <egtvedt@samfundet.no>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

... by turning it into what used to be multipages counterpart

Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull MMC fixes from Ulf Hansson:
 "MMC host:
   - omap/omap_hsmmc: Initialize dma_slave_config to avoid random data
   - sdhci-st: Handle interconnect clock"

* tag 'mmc-v4.8-rc6' of git://git.linaro.org/people/ulf.hansson/mmc:
  mmc: omap: Initialize dma_slave_config to avoid random data in it's fields
  mmc: omap_hsmmc: Initialize dma_slave_config to avoid random data
  mmc: sdhci-st: Handle interconnect clock
  dt-bindings: mmc: sdhci-st: Mention the discretionary "icn" clock

Pull powerpc fixes from Michael Ellerman:
 "Fixes for code merged this cycle:

   - Fix restore of SPRs upon wake up from hypervisor state loss from
     Gautham R  Shenoy
   - Fix the state of root PE from Gavin Shan
   - Detach from PE on releasing PCI device from Gavin Shan
   - Fix size of NUM_CPU_FTR_KEYS on 32-bit
   - Fix missed TCE invalidations that should fallback to OPAL"

* tag 'powerpc-4.8-6' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/powernv/pci: Fix missed TCE invalidations that should fallback to OPAL
  powerpc/powernv: Detach from PE on releasing PCI device
  powerpc/powernv: Fix the state of root PE
  powerpc/kernel: Fix size of NUM_CPU_FTR_KEYS on 32-bit
  powerpc/powernv: Fix restore of SPRs upon wake up from hypervisor state loss

Pull cifs fixes from Steve French:
 "Small set of cifs fixes"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  Move check for prefix path to within cifs_get_root()
  Compare prepaths when comparing superblocks
  Fix memory leaks in cifs_do_mount()

Pull nfsd bugfix from Bruce Fields:
 "Fix a memory corruption bug that I introduced in 4.7"

* tag 'nfsd-4.8-2' of git://linux-nfs.org/~bfields/linux:
  svcauth_gss: Revert 64c59a37 ("Remove unnecessary allocation")

Pull drm fixes from Dave Airlie:
 "Two sets of i915 fixes, one set of vc4 crasher fixes, and a couple of
  atmel fixes.

  Nothing too out there at this stage, though I think some people are
  holidaying so it's been quiet enough"

* tag 'drm-fixes-for-4.8-rc6' of git://people.freedesktop.org/~airlied/linux:
  drm/i915: Ignore OpRegion panel type except on select machines
  Revert "drm/i915/psr: Make idle_frames sensible again"
  drm/i915: Restore lost "Initialized i915" welcome message
  drm/vc4: mark vc4_bo_cache_purge() static
  drm/i915: Add GEN7_PCODE_MIN_FREQ_TABLE_GT_RATIO_OUT_OF_RANGE to SNB
  drm/i915: disable 48bit full PPGTT when vGPU is active
  drm/i915: enable vGPU detection for all
  drm/atmel-hlcdc: Make ->reset() implementation static
  drm: atmel-hlcdc: Fix vertical scaling
  drm/vc4: Allow some more signals to be packed with uniform resets.
  drm/i915/dvo: Remove dangling call to drm_encoder_cleanup()

Pull power management fix from Rafael Wysocki:
 "More annotations of tracepoints in the runtime PM framework to prevent
  RCU from complaining when that code is invoked from the idle path
  (Paul McKenney)"

* tag 'pm-4.8-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  PM / runtime: Use _rcuidle for runtime suspend tracepoints

This pull request brings in a fix for crashes in X on VC4.

* tag 'drm-vc4-fixes-2016-09-14' of https://github.com/anholt/linux:
  drm/vc4: mark vc4_bo_cache_purge() static
  drm/vc4: Allow some more signals to be packed with uniform resets.

i915 fixes from Jani.

* tag 'drm-intel-fixes-2016-09-15' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: Ignore OpRegion panel type except on select machines
  Revert "drm/i915/psr: Make idle_frames sensible again"
  drm/i915: Restore lost "Initialized i915" welcome message

Pull rdma fixes from Doug Ledford:
 "Round three of 4.8 rc fixes.

  This is likely the last rdma pull request this cycle.  The new rxe
  driver had a few issues (you probably saw the boot bot bug report) and
  they should be addressed now.  There are a couple other fixes here,
  mainly mlx4.  There are still two outstanding issues that need
  resolved but I don't think their fix will make this kernel cycle.

  Summary:

   - Various fixes to rdmavt, ipoib, mlx5, mlx4, rxe"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dledford/rdma:
  IB/rdmavt: Don't vfree a kzalloc'ed memory region
  IB/rxe: Fix kmem_cache leak
  IB/rxe: Fix race condition between requester and completer
  IB/rxe: Fix duplicate atomic request handling
  IB/rxe: Fix kernel panic in udp_setup_tunnel
  IB/mlx5: Set source mac address in FTE
  IB/mlx5: Enable MAD_IFC commands for IB ports only
  IB/mlx4: Diagnostic HW counters are not supported in slave mode
  IB/mlx4: Use correct subnet-prefix in QP1 mads under SR-IOV
  IB/mlx4: Fix code indentation in QP1 MAD flow
  IB/mlx4: Fix incorrect MC join state bit-masking on SR-IOV
  IB/ipoib: Don't allow MC joins during light MC flush
  IB/rxe: fix GFP_KERNEL in spinlock context

Pull ARM SoC fixes from Arnd Bergmann:
 "Here are a couple of bugfixes for v4.8-rc.

  Most of them have actually been around for a while this time but for
  some reason didn't get applied early on.  The shmobile regulator fix
  is the only one that isn't completely obvious.

  Device tree changes:
   - archtimer interrupts must be level triggered (multiple platforms)
   - fix for USB and MMC clocks on STiH410
   - fix split DT repository in case of raspberry-pi 3
   - a new use of skeleton.dtsi on arm64 has crept in after that was
     removed.

  defconfig updates:
   - xilinx vdma has a new Kconfig symbol name
   - keystone requires CONFIG_NOP_USB_XCEIV since v4.8-rc1

  Code fixes:
   - fix regulator quirk on shmobile
   - suspend-to-ram regression on EXYNOS

  Maintainer updates:
   - Javier Martinez Canillas is now a reviewer for Samsung EXYNOS"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc:
  ARM: keystone: defconfig: Fix USB configuration
  arm64: dts: Fix broken architected timer interrupt trigger
  ARM: multi_v7_defconfig: update XILINX_VDMA
  ARM64: dts: bcm: Use a symlink to R-Pi dtsi files from arch=arm
  ARM: dts: Remove use of skeleton.dtsi from bcm283x.dtsi
  ARM: dts: STiH407-family: Provide interconnect clock for consumption in ST SDHCI
  ARM: dts: STiH410: Handle interconnect clock required by EHCI/OHCI (USB)
  ARM: shmobile: fix regulator quirk for Gen2
  ARM: EXYNOS: Clear OF_POPULATED flag from PMU node in IRQ init callback
  MAINTAINERS: Add myself as reviewer for Samsung Exynos support

Pull ARM fixes from Russell King:
 "Most of this update are fixes primarily discovered from testing on the
  older StrongARM 1110 and PXA systems, as a result of recent interest
  from several people in these platforms:

   - Locomo interrupt handling incorrectly stores the handler data in
     the chip's private data slot: when Locomo is combined with an
     interrupt controller who's chip uses the chip private data, this
     leads to an oops.

   - SA1111 was missing a call to clk_disable() to clean up after a
     failed probe.

   - SA1111 and PCMCIA suspend/resume was broken:

     The PCMCIA "ds" layer was using the legacy bus suspend/resume
     methods, which the core PM code is no longer calling as a result of
     device_pm_check_callbacks() introduced in commit aa8e54b5
     ("PM / sleep: Go direct_complete if driver has no callbacks").

     SA1111 was broken due to changes to PCMCIA which makes PCMCIA
     suspend itself later than the SA1111 code expects, and resume
     before the SA1111 code has initialised access to the pcmcia
     sub-device.

   - the default SA1111 interrupt mask polarity got messed up when it
     was converted to use a dynamic interrupt base number for its
     interrupts.

   - fix platform_get_irq() error code propagation, which was causing
     problems on platforms where the interrupt may not be available at
      probe time in DT setups.

   - fix the lack of clock to PCMCIA code on PXA platforms, which was
     omitted in conversions of PXA to CCF.

   - fix an oops in the PXA PCMCIA code caused by a previous commit not
     realising that Lubbock is different from the rest of the PXA PCMCIA
     drivers.

   - ensure that SA1111 low-level PCMCIA drivers propagate their error
     codes to the main probe function, rather than the driver silently
     accepting a failure.

   - fix the sa11xx debugfs reporting of timing information, which
     always indicated zero due to the clock being a factor of 1000 out.

   - fix the polarity of the status change signal reported from the
     sockets.

  Lastly, one ARM specific commit from Stefan Agner fixing the LPAE
  cache attributes"

* 'fixes' of git://git.armlinux.org.uk/~rmk/linux-arm:
  ARM: pxa/lubbock: add pcmcia clock
  ARM: locomo: fix locomo irq handling
  ARM: 8612/1: LPAE: initialize cache policy correctly
  ARM: sa1111: fix missing clk_disable()
  ARM: sa1111: fix pcmcia suspend/resume
  ARM: sa1111: fix pcmcia interrupt mask polarity
  ARM: sa1111: fix error code propagation in sa1111_probe()
  pcmcia: lubbock: fix sockets configuration
  pcmcia: sa1111: fix propagation of lowlevel board init return code
  pcmcia: soc_common: fix SS_STSCHG polarity
  pcmcia: sa11xx_base: add units to the timing information
  pcmcia: sa11xx_base: fix reporting of timing information
  pcmcia: ds: fix suspend/resume

The userspace memory region 'mr' is allocated with kzalloc in
__rvt_alloc_mr  however it is incorrectly being freed with vfree in
__rvt_free_mr. Fix this by using kfree to free it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

Decrement qp reference when handling error path
in completer to prevent kmem_cache leak.

Fixes: 8700e3e7 ("Soft RoCE driver")
Signed-off-by: Yonatan Cohen <yonatanc@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

rxe_requester() is sending a pkt with rxe_xmit_packet() and
then calls rxe_update() to update the wqe and qp's psn values.
But sometimes the response is received before the requester
had time to update the wqe in which case the completer
acts on errornous wqe values.
This fix updates the wqe and qp before actually sending
the request and rolls back when xmit fails.

Fixes: 8700e3e7 ("Soft RoCE driver")
Signed-off-by: Yonatan Cohen <yonatanc@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

When handling ack for atomic opcodes like "fetch&add"
or "cmp&swp", the method send_atomic_ack() saves the ack
before sending it, in case it gets lost and never reach the
requester. In which case the method duplicate_request()
will need to find it using the duplicated request.psn.
But send_atomic_ack() used a wrong psn value and thus
the above ack was never found.
This fix uses the ack.psn to locate the ack in case
its needed.
This fix also copies the ack packet to the skb's control buffer
since duplicate_request() will need it when calling rxe_xmit_packet()

Fixes: 8700e3e7 ("Soft RoCE driver")
Signed-off-by: Yonatan Cohen <yonatanc@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

Disable creation of a UDP socket for ipv6 when
CONFIG_IPV6 is not enabeld. Since udp_sock_create6()
returns 0 when CONFIG_IPV6 is not set

[   46.888632] IP: [<c220705a>] setup_udp_tunnel_sock+0x6/0x4f
[   46.891355] *pdpt = 0000000000000000 *pde = f000ff53f000ff53
[   46.893918] Oops: 0002 [#1] PREEMPT
[   46.896014] CPU: 0 PID: 1 Comm: swapper Not tainted 4.7.0-rc4-00001-g8700e3e7 #1
[   46.900280] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Debian-1.8.2-1 04/01/2014
[   46.904905] task: cf06c040 ti: cf05e000 task.ti: cf05e000
[   46.907854] EIP: 0060:[<c220705a>] EFLAGS: 00210246 CPU: 0
[   46.911137] EIP is at setup_udp_tunnel_sock+0x6/0x4f
[   46.914070] EAX: 00000044 EBX: 00000001 ECX: cf05fef0 EDX: ca8142e0
[   46.917236] ESI: c2c4505b EDI: cf05fef0 EBP: cf05fed0 ESP: cf05fed0
[   46.919836]  DS: 007b ES: 007b FS: 0000 GS: 00e0 SS: 0068
[   46.922046] CR0: 80050033 CR2: 000001fc CR3: 02cec000 CR4: 000006b0
[   46.924550] Stack:
[   46.926014]  cf05ff10 c1fd4657 ca8142e0 0000000a 00000000 00000000 0000b712 00000008
[   46.931274]  00000000 6bb5bd01 c1fd48de 00000000 00000000 cf05ff1c 00000000 00000000
[   46.936122]  cf05ff1c c1fd4bdf 00000000 cf05ff28 c2c4507b ffffffff cf05ff88 c2bf1c74
[   46.942350] Call Trace:
[   46.944403]  [<c1fd4657>] rxe_setup_udp_tunnel+0x8f/0x99
[   46.947689]  [<c1fd48de>] ? net_to_rxe+0x4e/0x4e
[   46.950567]  [<c1fd4bdf>] rxe_net_init+0xe/0xa4
[   46.953147]  [<c2c4507b>] rxe_module_init+0x20/0x4c
[   46.955448]  [<c2bf1c74>] do_one_initcall+0x89/0x113
[   46.957797]  [<c2bf15eb>] ? set_debug_rodata+0xf/0xf
[   46.959966]  [<c2bf1dbc>] ? kernel_init_freeable+0xbe/0x15b
[   46.962262]  [<c2bf1ddc>] kernel_init_freeable+0xde/0x15b
[   46.964418]  [<c232eb54>] kernel_init+0x8/0xd0
[   46.966618]  [<c2333122>] ret_from_kernel_thread+0xe/0x24
[   46.969592]  [<c232eb4c>] ? rest_init+0x6f/0x6f

Fixes: 8700e3e7 ("Soft RoCE driver")
Signed-off-by: Yonatan Cohen <yonatanc@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

Set the source mac address in the FTE when L2 specification
is provided.

Fixes: 038d2ef8 ('IB/mlx5: Add flow steering support')
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

MAD_IFC command is supported only for physical functions (PF)
and when physical port is IB. The proposed fix enforces it.

Fixes: d603c809 ("IB/mlx5: Fix decision on using MAD_IFC")
Reported-by: David Chang <dchang@suse.com>
Signed-off-by: Noa Osherovich <noaos@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

Modify the mlx4_ib_diag_counters() to avoid the following error in the
hypervisor when the slave tries to query the hardware counters in SR-IOV
mode.

mlx4_core 0000:81:00.0: Unknown command:0x30 accepted from slave:1

Fixes: 3f85f2aa ("IB/mlx4: Add diagnostic hardware counters")
Signed-off-by: Kamal Heib <kamalh@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

When sending QP1 MAD packets which use a GRH, the source GID
(which consists of the 64-bit subnet prefix, and the 64 bit port GUID)
must be included in the packet GRH.

For SR-IOV, a GID cache is used, since the source GID needs to be the
slave's source GID, and not the Hypervisor's GID. This cache also
included a subnet_prefix. Unfortunately, the subnet_prefix field in
the cache was never initialized (to the default subnet prefix 0xfe80::0).
As a result, this field remained all zeroes.  Therefore, when SR-IOV
was active, all QP1 packets which included a GRH had a source GID
subnet prefix of all-zeroes.

However, the subnet-prefix should initially be 0xfe80::0 (the default
subnet prefix). In addition, if OpenSM modifies a port's subnet prefix,
the new subnet prefix must be used in the GRH when sending QP1 packets.
To fix this we now initialize the subnet prefix in the SR-IOV GID cache
to the default subnet prefix. We update the cached value if/when OpenSM
modifies the port's subnet prefix. We take this cached value when sending
QP1 packets when SR-IOV is active.

Note that the value is stored as an atomic64. This eliminates any need
for locking when the subnet prefix is being updated.

Note also that we depend on the FW generating the "port management change"
event for tracking subnet-prefix changes performed by OpenSM. If running
early FW (before 2.9.4630), subnet prefix changes will not be tracked (but
the default subnet prefix still will be stored in the cache; therefore
users who do not modify the subnet prefix will not have a problem).
IF there is a need for such tracking also for early FW, we will add that
capability in a subsequent patch.

Fixes: 1ffeb2eb ("IB/mlx4: SR-IOV IB context objects and proxy/tunnel SQP support")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>