This adds fields to the struct kvm_vcpu_arch to store the new
guest-accessible SPRs on POWER8, adds code to the get/set_one_reg
functions to allow userspace to access this state, and adds code to
the guest entry and exit to context-switch these SPRs between host
and guest.

Note that DPDES (Directed Privileged Doorbell Exception State) is
shared between threads on a core; hence we store it in struct
kvmppc_vcore and have the master thread save and restore it.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

On a threaded processor such as POWER7, we group VCPUs into virtual
cores and arrange that the VCPUs in a virtual core run on the same
physical core.  Currently we don't enforce any correspondence between
virtual thread numbers within a virtual core and physical thread
numbers.  Physical threads are allocated starting at 0 on a first-come
first-served basis to runnable virtual threads (VCPUs).

POWER8 implements a new "msgsndp" instruction which guest kernels can
use to interrupt other threads in the same core or sub-core.  Since
the instruction takes the destination physical thread ID as a parameter,
it becomes necessary to align the physical thread IDs with the virtual
thread IDs, that is, to make sure virtual thread N within a virtual
core always runs on physical thread N.

This means that it's possible that thread 0, which is where we call
__kvmppc_vcore_entry, may end up running some other vcpu than the
one whose task called kvmppc_run_core(), or it may end up running
no vcpu at all, if for example thread 0 of the virtual core is
currently executing in userspace.  However, we do need thread 0
to be responsible for switching the MMU -- a previous version of
this patch that had other threads switching the MMU was found to
be responsible for occasional memory corruption and machine check
interrupts in the guest on POWER7 machines.

To accommodate this, we no longer pass the vcpu pointer to
__kvmppc_vcore_entry, but instead let the assembly code load it from
the PACA.  Since the assembly code will need to know the kvm pointer
and the thread ID for threads which don't have a vcpu, we move the
thread ID into the PACA and we add a kvm pointer to the virtual core
structure.

In the case where thread 0 has no vcpu to run, it still calls into
kvmppc_hv_entry in order to do the MMU switch, and then naps until
either its vcpu is ready to run in the guest, or some other thread
needs to exit the guest.  In the latter case, thread 0 jumps to the
code that switches the MMU back to the host.  This control flow means
that now we switch the MMU before loading any guest vcpu state.
Similarly, on guest exit we now save all the guest vcpu state before
switching the MMU back to the host.  This has required substantial
code movement, making the diff rather large.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

POWER8 doesn't have the DABR and DABRX registers; instead it has
new DAWR/DAWRX registers, which will be handled in a later patch.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Simplify the handling of lazy EE by going directly from fully-enabled
to hard-disabled.  This replaces the lazy_irq_pending() check
(including its misplaced kvm_guest_exit() call).

As suggested by Tiejun Chen, move the interrupt disabling into
kvmppc_prepare_to_enter() rather than have each caller do it.  Also
move the IRQ enabling on heavyweight exit into
kvmppc_prepare_to_enter().
Signed-off-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Use gva_t instead of unsigned int for eaddr in deliver_tlb_miss().
Signed-off-by: NMihai Caraman <mihai.caraman@freescale.com>
CC: stable@vger.kernel.org
Signed-off-by: NAlexander Graf <agraf@suse.de>

Signed-off-by: NAndreas Schwab <schwab@linux-m68k.org>
CC: stable@vger.kernel.org
Signed-off-by: NAlexander Graf <agraf@suse.de>

MMIO emulation reads the last instruction executed by the guest
and then emulates. If the guest is running in Little Endian order,
or more generally in a different endian order of the host, the
instruction needs to be byte-swapped before being emulated.

This patch adds a helper routine which tests the endian order of
the host and the guest in order to decide whether a byteswap is
needed or not. It is then used to byteswap the last instruction
of the guest in the endian order of the host before MMIO emulation
is performed.

Finally, kvmppc_handle_load() of kvmppc_handle_store() are modified
to reverse the endianness of the MMIO if required.
Signed-off-by: NCédric Le Goater <clg@fr.ibm.com>
[agraf: add booke handling]
Signed-off-by: NAlexander Graf <agraf@suse.de>

We had code duplication between the inline functions to get our last
instruction on normal interrupts and system call interrupts. Unify
both helper functions towards a single implementation.
Signed-off-by: NAlexander Graf <agraf@suse.de>

NULL return of kvmppc_mmu_hpte_cache_next should be handled
Signed-off-by: NZhouyi Zhou <yizhouzhou@ict.ac.cn>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Rather than calling hard_irq_disable() when we're back in C code
we can just call RECONCILE_IRQ_STATE to soft disable IRQs while
we're already in hard disabled state.

This should be functionally equivalent to the code before, but
cleaner and faster.
Signed-off-by: NTiejun Chen <tiejun.chen@windriver.com>
[agraf: fix comment, commit message]
Signed-off-by: NAlexander Graf <agraf@suse.de>

KVM uses same WIM tlb attributes as the corresponding qemu pte.
For this we now search the linux pte for the requested page and
get these cache caching/coherency attributes from pte.
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Reviewed-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

We need to search linux "pte" to get "pte" attributes for setting TLB in KVM.
This patch defines a lookup_linux_ptep() function which returns pte pointer.
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Reviewed-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

lookup_linux_pte() is doing more than lookup, updating the pte,
so for clarity it is renamed to lookup_linux_pte_and_update()
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Reviewed-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

On booke, "struct tlbe_ref" contains host tlb mapping information
(pfn: for guest-pfn to pfn, flags: attribute associated with this mapping)
for a guest tlb entry. So when a guest creates a TLB entry then
"struct tlbe_ref" is set to point to valid "pfn" and set attributes in
"flags" field of the above said structure. When a guest TLB entry is
invalidated then flags field of corresponding "struct tlbe_ref" is
updated to point that this is no more valid, also we selectively clear
some other attribute bits, example: if E500_TLB_BITMAP was set then we clear
E500_TLB_BITMAP, if E500_TLB_TLB0 is set then we clear this.

Ideally we should clear complete "flags" as this entry is invalid and does not
have anything to re-used. The other part of the problem is that when we use
the same entry again then also we do not clear (started doing or-ing etc).

So far it was working because the selectively clearing mentioned above
actually clears "flags" what was set during TLB mapping. But the problem
starts coming when we add more attributes to this then we need to selectively
clear them and which is not needed.
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Reviewed-by: NScott Wood <scottwood@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This modifies kvmppc_load_fp and kvmppc_save_fp to use the generic
FP/VSX and VMX load/store functions instead of open-coding the
FP/VSX/VMX load/store instructions.  Since kvmppc_load/save_fp don't
follow C calling conventions, we make them private symbols within
book3s_hv_rmhandlers.S.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Now that we have the vcpu floating-point and vector state stored in
the same type of struct as the main kernel uses, we can load that
state directly from the vcpu struct instead of having extra copies
to/from the thread_struct.  Similarly, when the guest state needs to
be saved, we can have it saved it directly to the vcpu struct by
setting the current->thread.fp_save_area and current->thread.vr_save_area
pointers.  That also means that we don't need to back up and restore
userspace's FP/vector state.  This all makes the code simpler and
faster.

Note that it's not necessary to save or modify current->thread.fpexc_mode,
since nothing in KVM uses or is affected by its value.  Nor is it
necessary to touch used_vr or used_vsr.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

This uses struct thread_fp_state and struct thread_vr_state to store
the floating-point, VMX/Altivec and VSX state, rather than flat arrays.
This makes transferring the state to/from the thread_struct simpler
and allows us to unify the get/set_one_reg implementations for the
VSX registers.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

The load_up_fpu and load_up_altivec functions were never intended to
be called from C, and do things like modifying the MSR value in their
callers' stack frames, which are assumed to be interrupt frames.  In
addition, on 32-bit Book S they require the MMU to be off.

This makes KVM use the new load_fp_state() and load_vr_state() functions
instead of load_up_fpu/altivec.  This means we can remove the assembler
glue in book3s_rmhandlers.S, and potentially fixes a bug on Book E,
where load_up_fpu was called directly from C.
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

kvm_hypercall0() and friends have nothing KVM specific so moved to
epapr_hypercall0() and friends. Also they are moved from
arch/powerpc/include/asm/kvm_para.h to arch/powerpc/include/asm/epapr_hcalls.h
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

kvm_hypercall() have nothing KVM specific, so renamed to epapr_hypercall().
Also this in moved to arch/powerpc/include/asm/epapr_hcalls.h
Signed-off-by: NBharat Bhushan <bharat.bhushan@freescale.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

XICS failed to free xics structure on error path. MPIC destroy handler
forgot to delete kvm_device structure.
Signed-off-by: NGleb Natapov <gleb@redhat.com>
Acked-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Systems that support automatic loading of kernel modules through
device aliases should try and automatically load kvm when /dev/kvm
gets opened.

Add code to support that magic for all PPC kvm targets, even the
ones that don't support modules yet.
Signed-off-by: NAlexander Graf <agraf@suse.de>

In some scene, e.g openstack CI, PR guest can trigger "sc 1" frequently,
this patch optimizes the path by directly delivering BOOK3S_INTERRUPT_SYSCALL
to HV guest, so powernv can return to HV guest without heavy exit, i.e,
no need to swap TLB, HTAB,.. etc
Signed-off-by: NLiu Ping Fan <pingfank@linux.vnet.ibm.com>
Signed-off-by: NAlexander Graf <agraf@suse.de>

Using the address of 'empty_zero_page' as source address in order to
clear a page is wrong. On some architectures empty_zero_page is only the
pointer to the struct page of the empty_zero_page.  Therefore the clear
page operation would copy the contents of a couple of struct pages instead
of clearing a page.  For kvm only arm/arm64 are affected by this bug.

To fix this use the ZERO_PAGE macro instead which will return the struct
page address of the empty_zero_page on all architectures.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>

We should not be using jump labels before they were initialized. Push back
the callback to until after jump label initialization.
Signed-off-by: NSasha Levin <sasha.levin@oracle.com>
Signed-off-by: NGleb Natapov <gleb@redhat.com>

Fix percpu vmalloc allocations

Using virt_to_phys on percpu mappings is horribly wrong as it may be
backed by vmalloc.  Introduce kvm_kaddr_to_phys which translates both
types of valid kernel addresses to the corresponding physical address.

At the same time resolves a typing issue where we were storing the
physical address as a 32 bit unsigned long (on arm), truncating the
physical address for addresses above the 4GB limit.  This caused
breakage on Keystone.

Cc: <stable@vger.kernel.org>	[3.10+]
Reported-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: NSantosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: NMarc Zyngier <marc.zyngier@arm.com>
Signed-off-by: NChristoffer Dall <christoffer.dall@linaro.org>

Pull KVM changes from Paolo Bonzini:
 "Here are the 3.13 KVM changes.  There was a lot of work on the PPC
  side: the HV and emulation flavors can now coexist in a single kernel
  is probably the most interesting change from a user point of view.

  On the x86 side there are nested virtualization improvements and a few
  bugfixes.

  ARM got transparent huge page support, improved overcommit, and
  support for big endian guests.

  Finally, there is a new interface to connect KVM with VFIO.  This
  helps with devices that use NoSnoop PCI transactions, letting the
  driver in the guest execute WBINVD instructions.  This includes some
  nVidia cards on Windows, that fail to start without these patches and
  the corresponding userspace changes"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (146 commits)
  kvm, vmx: Fix lazy FPU on nested guest
  arm/arm64: KVM: PSCI: propagate caller endianness to the incoming vcpu
  arm/arm64: KVM: MMIO support for BE guest
  kvm, cpuid: Fix sparse warning
  kvm: Delete prototype for non-existent function kvm_check_iopl
  kvm: Delete prototype for non-existent function complete_pio
  hung_task: add method to reset detector
  pvclock: detect watchdog reset at pvclock read
  kvm: optimize out smp_mb after srcu_read_unlock
  srcu: API for barrier after srcu read unlock
  KVM: remove vm mmap method
  KVM: IOMMU: hva align mapping page size
  KVM: x86: trace cpuid emulation when called from emulator
  KVM: emulator: cleanup decode_register_operand() a bit
  KVM: emulator: check rex prefix inside decode_register()
  KVM: x86: fix emulation of "movzbl %bpl, %eax"
  kvm_host: typo fix
  KVM: x86: emulate SAHF instruction
  MAINTAINERS: add tree for kvm.git
  Documentation/kvm: add a 00-INDEX file
  ...

Pull Xen updates from Konrad Rzeszutek Wilk:
 "This has tons of fixes and two major features which are concentrated
  around the Xen SWIOTLB library.

  The short <blurb> is that the tracing facility (just one function) has
  been added to SWIOTLB to make it easier to track I/O progress.
  Additionally under Xen and ARM (32 & 64) the Xen-SWIOTLB driver
  "is used to translate physical to machine and machine to physical
  addresses of foreign[guest] pages for DMA operations" (Stefano) when
  booting under hardware without proper IOMMU.

  There are also bug-fixes, cleanups, compile warning fixes, etc.

  The commit times for some of the commits is a bit fresh - that is b/c
  we wanted to make sure we have the Ack's from the ARM folks - which
  with the string of back-to-back conferences took a bit of time.  Rest
  assured - the code has been stewing in #linux-next for some time.

  Features:
   - SWIOTLB has tracing added when doing bounce buffer.
   - Xen ARM/ARM64 can use Xen-SWIOTLB.  This work allows Linux to
     safely program real devices for DMA operations when running as a
     guest on Xen on ARM, without IOMMU support. [*1]
   - xen_raw_printk works with PVHVM guests if needed.

  Bug-fixes:
   - Make memory ballooning work under HVM with large MMIO region.
   - Inform hypervisor of MCFG regions found in ACPI DSDT.
   - Remove deprecated IRQF_DISABLED.
   - Remove deprecated __cpuinit.

  [*1]:
  "On arm and arm64 all Xen guests, including dom0, run with second
   stage translation enabled.  As a consequence when dom0 programs a
   device for a DMA operation is going to use (pseudo) physical
   addresses instead machine addresses.  This work introduces two trees
   to track physical to machine and machine to physical mappings of
   foreign pages.  Local pages are assumed mapped 1:1 (physical address
   == machine address).  It enables the SWIOTLB-Xen driver on ARM and
   ARM64, so that Linux can translate physical addresses to machine
   addresses for dma operations when necessary.  " (Stefano)"

* tag 'stable/for-linus-3.13-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (32 commits)
  xen/arm: pfn_to_mfn and mfn_to_pfn return the argument if nothing is in the p2m
  arm,arm64/include/asm/io.h: define struct bio_vec
  swiotlb-xen: missing include dma-direction.h
  pci-swiotlb-xen: call pci_request_acs only ifdef CONFIG_PCI
  arm: make SWIOTLB available
  xen: delete new instances of added __cpuinit
  xen/balloon: Set balloon's initial state to number of existing RAM pages
  xen/mcfg: Call PHYSDEVOP_pci_mmcfg_reserved for MCFG areas.
  xen: remove deprecated IRQF_DISABLED
  x86/xen: remove deprecated IRQF_DISABLED
  swiotlb-xen: fix error code returned by xen_swiotlb_map_sg_attrs
  swiotlb-xen: static inline xen_phys_to_bus, xen_bus_to_phys, xen_virt_to_bus and range_straddles_page_boundary
  grant-table: call set_phys_to_machine after mapping grant refs
  arm,arm64: do not always merge biovec if we are running on Xen
  swiotlb: print a warning when the swiotlb is full
  swiotlb-xen: use xen_dma_map/unmap_page, xen_dma_sync_single_for_cpu/device
  xen: introduce xen_dma_map/unmap_page and xen_dma_sync_single_for_cpu/device
  tracing/events: Fix swiotlb tracepoint creation
  swiotlb-xen: use xen_alloc/free_coherent_pages
  xen: introduce xen_alloc/free_coherent_pages
  ...

Pull virtio updates from Rusty Russell:
 "Nothing really exciting: some groundwork for changing virtio endian,
  and some robustness fixes for broken virtio devices, plus minor
  tweaks"

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  virtio_scsi: verify if queue is broken after virtqueue_get_buf()
  x86, asmlinkage, lguest: Pass in globals into assembler statement
  virtio: mmio: fix signature checking for BE guests
  virtio_ring: adapt to notify() returning bool
  virtio_net: verify if queue is broken after virtqueue_get_buf()
  virtio_console: verify if queue is broken after virtqueue_get_buf()
  virtio_blk: verify if queue is broken after virtqueue_get_buf()
  virtio_ring: add new function virtqueue_is_broken()
  virtio_test: verify if virtqueue_kick() succeeded
  virtio_net: verify if virtqueue_kick() succeeded
  virtio_ring: let virtqueue_{kick()/notify()} return a bool
  virtio_ring: change host notification API
  virtio_config: remove virtio_config_val
  virtio: use size-based config accessors.
  virtio_config: introduce size-based accessors.
  virtio_ring: plug kmemleak false positive.
  virtio: pm: use CONFIG_PM_SLEEP instead of CONFIG_PM

Pull module updates from Rusty Russell:
 "Mainly boring here, too.  rmmod --wait finally removed, though"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  modpost: fix bogus 'exported twice' warnings.
  init: fix in-place parameter modification regression
  asmlinkage, module: Make ksymtab and kcrctab symbols and __this_module __visible
  kernel: add support for init_array constructors
  modpost: Optionally ignore secondary errors seen if a single module build fails
  module: remove rmmod --wait option.

Merge patches from Andrew Morton:
 - memstick fixes

 - the rest of MM

 - various misc bits that were awaiting merges from linux-next into
   mainline: seq_file, printk, rtc, completions, w1, softirqs, llist,
   kfifo, hfsplus

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (72 commits)
  cmdline-parser: fix build
  hfsplus: Fix undefined __divdi3 in hfsplus_init_header_node()
  kfifo API type safety
  kfifo: kfifo_copy_{to,from}_user: fix copied bytes calculation
  sound/core/memalloc.c: use gen_pool_dma_alloc() to allocate iram buffer
  llists-move-llist_reverse_order-from-raid5-to-llistc-fix
  llists: move llist_reverse_order from raid5 to llist.c
  kernel: fix generic_exec_single indentation
  kernel-provide-a-__smp_call_function_single-stub-for-config_smp-fix
  kernel: provide a __smp_call_function_single stub for !CONFIG_SMP
  kernel: remove CONFIG_USE_GENERIC_SMP_HELPERS
  revert "softirq: Add support for triggering softirq work on softirqs"
  drivers/w1/masters/w1-gpio.c: use dev_get_platdata()
  sched: remove INIT_COMPLETION
  tree-wide: use reinit_completion instead of INIT_COMPLETION
  sched: replace INIT_COMPLETION with reinit_completion
  drivers/rtc/rtc-hid-sensor-time.c: enable HID input processing early
  drivers/rtc/rtc-hid-sensor-time.c: use dev_get_platdata()
  vsprintf: ignore %n again
  seq_file: remove "%n" usage from seq_file users
  ...

Fix following errors:

  include/linux/cmdline-parser.h:17:12: error: 'BDEVNAME_SIZE' undeclared here
  block/cmdline-parser.c:17:2: error: implicit declaration of function 'kzalloc'
Signed-off-by: NAlexander Beregalov <alexander.beregalov@intel.com>
Cc: CaiZhiyong <caizhiyong@huawei.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

ERROR: "__divdi3" [fs/hfsplus/hfsplus.ko] undefined!

Introduced by commit 099e9245 ("hfsplus: implement attributes file's
header node initialization code").

i_size_read() returns loff_t, which is long long, i.e.  64-bit.  node_size
is size_t, which is either 32-bit or 64-bit.  Hence
"i_size_read(attr_file) / node_size" is a 64-by-32 or 64-by-64 division,
causing (some versions of) gcc to emit a call to __divdi3().

Fortunately node_size is actually 16-bit, as the sole caller of
hfsplus_init_header_node() passes a u16.  Hence change its type from
size_t to u16, and use do_div() to perform a 64-by-32 division.

Not seen in m68k/allmodconfig in -next, so it really depends on the
verion of gcc.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Cc: Vyacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch enhances the type safety for the kfifo API.  It is now safe
to put const data into a non const FIFO and the API will now generate a
compiler warning when reading from the fifo where the destination
address is pointing to a const variable.

As a side effect the kfifo_put() does now expect the value of an element
instead a pointer to the element.  This was suggested Russell King.  It
make the handling of the kfifo_put easier since there is no need to
create a helper variable for getting the address of a pointer or to pass
integers of different sizes.

IMHO the API break is okay, since there are currently only six users of
kfifo_put().

The code is also cleaner by kicking out the "if (0)" expressions.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NStefani Seibold <stefani@seibold.net>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

'copied' and 'len' are in bytes, while 'ret' is in elements, so we need to
multiply 'ret' with the size of one element to get the correct result.
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Cc: Stefani Seibold <stefani@seibold.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since gen_pool_dma_alloc() is introduced, we implement it to simplify code.
Signed-off-by: NNicolin Chen <b42378@freescale.com>
Acked-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fix comment typo, per Jan

Cc: Christoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Make this useful helper available for other users.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>