Commit Graph

115 Commits

Author SHA1 Message Date
Christophe Leroy 9d9f2cccde powerpc/mm: change #include "mmu_decl.h" to <mm/mmu_decl.h>
This patch make inclusion of mmu_decl.h independant of the location
of the file including it.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-02 21:18:58 +10:00
Qian Cai c38ca26552 powerpc/mm: fix "section_base" set but not used
The commit 24b6d41643 ("mm: pass the vmem_altmap to vmemmap_free")
removed a line in vmemmap_free(),

altmap = to_vmem_altmap((unsigned long) section_base);

but left a variable no longer used.

arch/powerpc/mm/init_64.c: In function 'vmemmap_free':
arch/powerpc/mm/init_64.c:277:16: error: variable 'section_base' set but
not used [-Werror=unused-but-set-variable]

Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-03-02 14:43:05 +11:00
Oliver O'Halloran 9ef34630a4 powerpc/mm: Fallback to RAM if the altmap is unusable
The "altmap" is used to provide a pool of memory that is reserved for
the vmemmap backing of hot-plugged memory. This is useful when adding
large amount of ZONE_DEVICE memory to a system with a limited amount of
normal memory.

On ppc64 we use huge pages to map the vmemmap which requires the backing
storage to be contigious and aligned to the hugepage size. The altmap
implementation allows for the altmap provider to reserve a few PFNs at
the start of the range for it's own uses and when this occurs the
first chunk of the altmap is not usable for hugepage mappings. On hash
there is no sane way to fall back to a normal sized page mapping so we
fail the allocation. This results in memory hotplug failing with
ENOMEM when the new range doesn't fall into an existing vmemmap block.

This patch handles this case by falling back to using system memory
rather than failing if we cannot allocate from the altmap. This
fallback should only ever be used for the first vmemmap block so it
should not cause excess memory consumption.

Fixes: 7b73d978a5 ("mm: pass the vmem_altmap to vmemmap_populate")
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-09 21:33:21 +11:00
Alexey Kardashevskiy 425333bf3a KVM: PPC: Avoid marking DMA-mapped pages dirty in real mode
At the moment the real mode handler of H_PUT_TCE calls iommu_tce_xchg_rm()
which in turn reads the old TCE and if it was a valid entry, marks
the physical page dirty if it was mapped for writing. Since it is in
real mode, realmode_pfn_to_page() is used instead of pfn_to_page()
to get the page struct. However SetPageDirty() itself reads the compound
page head and returns a virtual address for the head page struct and
setting dirty bit for that kills the system.

This adds additional dirty bit tracking into the MM/IOMMU API for use
in the real mode. Note that this does not change how VFIO and
KVM (in virtual mode) set this bit. The KVM (real mode) changes include:
- use the lowest bit of the cached host phys address to carry
the dirty bit;
- mark pages dirty when they are unpinned which happens when
the preregistered memory is released which always happens in virtual
mode;
- add mm_iommu_ua_mark_dirty_rm() helper to set delayed dirty bit;
- change iommu_tce_xchg_rm() to take the kvm struct for the mm to use
in the new mm_iommu_ua_mark_dirty_rm() helper;
- move iommu_tce_xchg_rm() to book3s_64_vio_hv.c (which is the only
caller anyway) to reduce the real mode KVM and IOMMU knowledge
across different subsystems.

This removes realmode_pfn_to_page() as it is not used anymore.

While we at it, remove some EXPORT_SYMBOL_GPL() as that code is for
the real mode only and modules cannot call it anyway.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-09-12 08:49:54 +10:00
Aneesh Kumar K.V cec4e9b28f powerpc/mm/radix: Parse disable_radix commandline correctly.
kernel parameter disable_radix takes different options
disable_radix=yes|no|1|0 or just disable_radix. When using the later
format we get below error.

 `Malformed early option 'disable_radix'`

Fixes: 1fd6c02207 ("powerpc/mm: Add a CONFIG option to choose if radix is used by default")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-04 16:59:36 +10:00
Aneesh Kumar K.V c2b4d8b741 powerpc/mm/hash64: Increase the VA range
This patch increases the max virtual (effective) address value to 4PB.
With 4K page size config we continue to limit ourself to 64TB.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Keep the H_PGTABLE_RANGE test, update it to work]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31 00:10:38 +11:00
Linus Torvalds 3ff1b28caa libnvdimm for 4.16
* Require struct page by default for filesystem DAX to remove a number of
   surprising failure cases.  This includes failures with direct I/O, gdb and
   fork(2).
 
 * Add support for the new Platform Capabilities Structure added to the NFIT in
   ACPI 6.2a.  This new table tells us whether the platform supports flushing
   of CPU and memory controller caches on unexpected power loss events.
 
 * Revamp vmem_altmap and dev_pagemap handling to clean up code and better
   support future future PCI P2P uses.
 
 * Deprecate the ND_IOCTL_SMART_THRESHOLD command whose payload has become
   out-of-sync with recent versions of the NVDIMM_FAMILY_INTEL spec, and
   instead rely on the generic ND_CMD_CALL approach used by the two other IOCTL
   families, NVDIMM_FAMILY_{HPE,MSFT}.
 
 * Enhance nfit_test so we can test some of the new things added in version 1.6
   of the DSM specification.  This includes testing firmware download and
   simulating the Last Shutdown State (LSS) status.
 -----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJaeOg0AAoJEJ/BjXdf9fLBAFoQAI/IgcgJ2h9lfEpgjBRTC44t
 2p8dxwT1Ofw3Y1aR/tI8nYRXjRtAGuP4UIeRVnb1CL/N7PagJyoMGU+6hmzg+ptY
 c7cEDvw6nZOhrFwXx/xn7R53sYG8zH+UE6+jTR/PP/G4mQJfFCg4iF9R72Y7z0n7
 aurf82Kz137NPUy6dNr4V9bmPMJWAaOci9WOj5SKddR5ZSNbjoxylTwQRvre5y4r
 7HQTScEkirABOdSf1JoXTSUXCH/RC9UFFXR03ScHstGb1HjCj3KdcicVc50Q++Ub
 qsEudhE6i44PEW1Hh4Qkg6hjHMEa8qHP+ShBuRuVaUmlghYTQn66niJAYLZilwdz
 EVjE7vR+toHA5g3YCalEmYVutUEhIDkh/xfpd7vM6ZorUGJy95a2elEJs2fHBffC
 gEhnCip7FROPcK5RDNUM8hBgnG/q5wwWPQMKY+6rKDZQx3mXssCrKp2Vlx7kBwMG
 rpblkEpYjPonbLEHxsSU8yTg9Uq55ciIWgnOToffcjZvjbihi8WUVlHcwHUMPf/o
 DWElg+4qmG0Sdd4S2NeAGwTl1Ewrf2RrtUGMjHtH4OUFs1wo6ZmfrxFzzMfoZ1Od
 ko/s65v4uwtTzECh2o+XQaNsReR5YETXxmA40N/Jpo7/7twABIoZ/ASvj/3ZBYj+
 sie+u2rTod8/gQWSfHpJ
 =MIMX
 -----END PGP SIGNATURE-----

Merge tag 'libnvdimm-for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Ross Zwisler:

 - Require struct page by default for filesystem DAX to remove a number
   of surprising failure cases. This includes failures with direct I/O,
   gdb and fork(2).

 - Add support for the new Platform Capabilities Structure added to the
   NFIT in ACPI 6.2a. This new table tells us whether the platform
   supports flushing of CPU and memory controller caches on unexpected
   power loss events.

 - Revamp vmem_altmap and dev_pagemap handling to clean up code and
   better support future future PCI P2P uses.

 - Deprecate the ND_IOCTL_SMART_THRESHOLD command whose payload has
   become out-of-sync with recent versions of the NVDIMM_FAMILY_INTEL
   spec, and instead rely on the generic ND_CMD_CALL approach used by
   the two other IOCTL families, NVDIMM_FAMILY_{HPE,MSFT}.

 - Enhance nfit_test so we can test some of the new things added in
   version 1.6 of the DSM specification. This includes testing firmware
   download and simulating the Last Shutdown State (LSS) status.

* tag 'libnvdimm-for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (37 commits)
  libnvdimm, namespace: remove redundant initialization of 'nd_mapping'
  acpi, nfit: fix register dimm error handling
  libnvdimm, namespace: make min namespace size 4K
  tools/testing/nvdimm: force nfit_test to depend on instrumented modules
  libnvdimm/nfit_test: adding support for unit testing enable LSS status
  libnvdimm/nfit_test: add firmware download emulation
  nfit-test: Add platform cap support from ACPI 6.2a to test
  libnvdimm: expose platform persistence attribute for nd_region
  acpi: nfit: add persistent memory control flag for nd_region
  acpi: nfit: Add support for detect platform CPU cache flush on power loss
  device-dax: Fix trailing semicolon
  libnvdimm, btt: fix uninitialized err_lock
  dax: require 'struct page' by default for filesystem dax
  ext2: auto disable dax instead of failing mount
  ext4: auto disable dax instead of failing mount
  mm, dax: introduce pfn_t_special()
  mm: Fix devm_memremap_pages() collision handling
  mm: Fix memory size alignment in devm_memremap_pages_release()
  memremap: merge find_dev_pagemap into get_dev_pagemap
  memremap: change devm_memremap_pages interface to use struct dev_pagemap
  ...
2018-02-06 10:41:33 -08:00
Christoph Hellwig a8fc357b28 mm: split altmap memory map allocation from normal case
No functional changes, just untangling the call chain and document
why the altmap is passed around the hotplug code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
Christoph Hellwig 24b6d41643 mm: pass the vmem_altmap to vmemmap_free
We can just pass this on instead of having to do a radix tree lookup
without proper locking a few levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
Christoph Hellwig 7b73d978a5 mm: pass the vmem_altmap to vmemmap_populate
We can just pass this on instead of having to do a radix tree lookup
without proper locking a few levels into the callchain.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2018-01-08 11:46:23 -08:00
Joe Perches f2c2cbcc35 powerpc: Use pr_warn instead of pr_warning
At some point, pr_warning will be removed so all logging messages use
a consistent <prefix>_warn style.

Update arch/powerpc/

Miscellanea:

o Coalesce formats
o Realign arguments
o Use %s, __func__ instead of embedded function names
o Remove unnecessary line continuations

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Geoff Levand <geoff@infradead.org>
[mpe: Rebase due to some %pOF changes.]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-12-04 11:54:34 +11:00
Michael Ellerman 1fd6c02207 powerpc/mm: Add a CONFIG option to choose if radix is used by default
Currently if the hardware supports the radix MMU we will use
it, *unless* "disable_radix" is passed on the kernel command line.

However some users would like the reverse semantics. ie. The kernel
uses the hash MMU by default, unless radix is explicitly requested on
the command line.

So add a CONFIG option to choose whether we use radix by default or
not, and expand the disable_radix command line option to allow
"disable_radix=no" which *enables* radix.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-06 16:48:15 +11:00
Michael Ellerman 4e00374704 powerpc/64s: Replace CONFIG_PPC_STD_MMU_64 with CONFIG_PPC_BOOK3S_64
CONFIG_PPC_STD_MMU_64 indicates support for the "standard" powerpc MMU
on 64-bit CPUs. The "standard" MMU refers to the hash page table MMU
found in "server" processors, from IBM mainly.

Currently CONFIG_PPC_STD_MMU_64 is == CONFIG_PPC_BOOK3S_64. While it's
annoying to have two symbols that always have the same value, it's not
quite annoying enough to bother removing one.

However with the arrival of Power9, we now have the situation where
CONFIG_PPC_STD_MMU_64 is enabled, but the kernel is running using the
Radix MMU - *not* the "standard" MMU. So it is now actively confusing
to use it, because it implies that code is disabled or inactive when
the Radix MMU is in use, however that is not necessarily true.

So s/CONFIG_PPC_STD_MMU_64/CONFIG_PPC_BOOK3S_64/, and do some minor
formatting updates of some of the affected lines.

This will be a pain for backports, but c'est la vie.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-06 16:48:14 +11:00
Michael Ellerman 7559952e1f powerpc/mm: Fix section mismatch warning in early_check_vec5()
early_check_vec5() is called from and calls __init routines, so should
also be __init.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-08-10 23:40:51 +10:00
Aneesh Kumar K.V 7e7dc66adc powerpc/mm: Build fix for non SPARSEMEM_VMEMAP config
We can use pfn_to_page() in realmode for other configs. Hence remove the
CONFIG_FLATMEM ifdef.

Fixes: 8e0861fa3c ("powerpc: Prepare to support kernel handling of IOMMU map/unmap")
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Also fix up the #endif comment]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-24 22:39:08 +10:00
Oliver O'Halloran b584c25440 powerpc/vmemmap: Add altmap support
Adds support to powerpc for the altmap feature of ZONE_DEVICE memory. An
altmap is a driver provided region that is used to provide the backing
storage for the struct pages of ZONE_DEVICE memory. In situations where
large amount of ZONE_DEVICE memory is being added to the system the
altmap reduces pressure on main system memory by allowing the mm/
metadata to be stored on the device itself rather in main memory.

Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-02 20:40:27 +10:00
Oliver O'Halloran d7d9b612f1 powerpc/vmemmap: Reshuffle vmemmap_free()
Removes an indentation level and shuffles some code around to make the
following patch cleaner. No functional changes.

Reviewed-by: Balbir Singh <bsingharora@gmail.com>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-07-02 20:40:26 +10:00
Anshuman Khandual 39e4675183 powerpc/mm: Add comments on vmemmap physical mapping
Adds some explaination on how the vmemmap based struct page layout's
physical mapping is allocated and tracked through linked list. It
also keeps note of a possible race condition.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-28 13:08:17 +10:00
Linus Torvalds 7246f60068 powerpc updates for 4.12 part 1.
Highlights include:
 
  - Larger virtual address space on 64-bit server CPUs. By default we use a 128TB
    virtual address space, but a process can request access to the full 512TB by
    passing a hint to mmap().
 
  - Support for the new Power9 "XIVE" interrupt controller.
 
  - TLB flushing optimisations for the radix MMU on Power9.
 
  - Support for CAPI cards on Power9, using the "Coherent Accelerator Interface
    Architecture 2.0".
 
  - The ability to configure the mmap randomisation limits at build and runtime.
 
  - Several small fixes and cleanups to the kprobes code, as well as support for
    KPROBES_ON_FTRACE.
 
  - Major improvements to handling of system reset interrupts, correctly treating
    them as NMIs, giving them a dedicated stack and using a new hypervisor call
    to trigger them, all of which should aid debugging and robustness.
 
 Many fixes and other minor enhancements.
 
 Thanks to:
   Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan,
   Aneesh Kumar K.V, Anshuman Khandual, Anton Blanchard, Balbir Singh, Ben
   Hutchings, Benjamin Herrenschmidt, Bhupesh Sharma, Chris Packham, Christian
   Zigotzky, Christophe Leroy, Christophe Lombard, Daniel Axtens, David Gibson,
   Gautham R. Shenoy, Gavin Shan, Geert Uytterhoeven, Guilherme G. Piccoli,
   Hamish Martin, Hari Bathini, Kees Cook, Laurent Dufour, Madhavan Srinivasan,
   Mahesh J Salgaonkar, Mahesh Salgaonkar, Masami Hiramatsu, Matt Brown, Matthew
   R. Ochs, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran,
   Pan Xinhui, Paul Mackerras, Rashmica Gupta, Russell Currey, Sukadev
   Bhattiprolu, Thadeu Lima de Souza Cascardo, Tobin C. Harding, Tyrel Datwyler,
   Uma Krishnan, Vaibhav Jain, Vipin K Parashar, Yang Shi.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJZDHUMAAoJEFHr6jzI4aWAT7oQALkE2Nj3gjcn1z0SkFhq/1iO
 Py9Elmqm4E+L6NKYtBY5dS8xVAJ088ffzERyqJ1FY1LHkB8tn8bWRcMQmbjAFzTI
 V4TAzDNI890BN/F4ptrYRwNFxRBHAvZ4NDunTzagwYnwmTzW9PYHmOi4pvWTo3Tw
 KFUQ0joLSEgHzyfXxYB3fyj41u8N0FZvhfazdNSqia2Y5Vwwv/ION5jKplDM+09Y
 EtVEXFvaKAS1sjbM/d/Jo5rblHfR0D9/lYV10+jjyIokjzslIpyTbnj3izeYoM5V
 I4h99372zfsEjBGPPXyM3khL3zizGMSDYRmJHQSaKxjtecS9SPywPTZ8ufO/aSzV
 Ngq6nlND+f1zep29VQ0cxd3Jh40skWOXzxJaFjfDT25xa6FbfsWP2NCtk8PGylZ7
 EyqTuCWkMgIP02KlX3oHvEB2LRRPCDmRU2zECecRGNJrIQwYC2xjoiVi7Q8Qe8rY
 gr7Ib5Jj/a+uiTcCIy37+5nXq2s14/JBOKqxuYZIxeuZFvKYuRUipbKWO05WDOAz
 m/pSzeC3J8AAoYiqR0gcSOuJTOnJpGhs7zrQFqnEISbXIwLW+ICumzOmTAiBqOEY
 Rt8uW2gYkPwKLrE05445RfVUoERaAjaE06eRMOWS6slnngHmmnRJbf3PcoALiJkT
 ediqGEj0/N1HMB31V5tS
 =vSF3
 -----END PGP SIGNATURE-----

Merge tag 'powerpc-4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Highlights include:

   - Larger virtual address space on 64-bit server CPUs. By default we
     use a 128TB virtual address space, but a process can request access
     to the full 512TB by passing a hint to mmap().

   - Support for the new Power9 "XIVE" interrupt controller.

   - TLB flushing optimisations for the radix MMU on Power9.

   - Support for CAPI cards on Power9, using the "Coherent Accelerator
     Interface Architecture 2.0".

   - The ability to configure the mmap randomisation limits at build and
     runtime.

   - Several small fixes and cleanups to the kprobes code, as well as
     support for KPROBES_ON_FTRACE.

   - Major improvements to handling of system reset interrupts,
     correctly treating them as NMIs, giving them a dedicated stack and
     using a new hypervisor call to trigger them, all of which should
     aid debugging and robustness.

   - Many fixes and other minor enhancements.

  Thanks to: Alastair D'Silva, Alexey Kardashevskiy, Alistair Popple,
  Andrew Donnellan, Aneesh Kumar K.V, Anshuman Khandual, Anton
  Blanchard, Balbir Singh, Ben Hutchings, Benjamin Herrenschmidt,
  Bhupesh Sharma, Chris Packham, Christian Zigotzky, Christophe Leroy,
  Christophe Lombard, Daniel Axtens, David Gibson, Gautham R. Shenoy,
  Gavin Shan, Geert Uytterhoeven, Guilherme G. Piccoli, Hamish Martin,
  Hari Bathini, Kees Cook, Laurent Dufour, Madhavan Srinivasan, Mahesh J
  Salgaonkar, Mahesh Salgaonkar, Masami Hiramatsu, Matt Brown, Matthew
  R. Ochs, Michael Neuling, Naveen N. Rao, Nicholas Piggin, Oliver
  O'Halloran, Pan Xinhui, Paul Mackerras, Rashmica Gupta, Russell
  Currey, Sukadev Bhattiprolu, Thadeu Lima de Souza Cascardo, Tobin C.
  Harding, Tyrel Datwyler, Uma Krishnan, Vaibhav Jain, Vipin K Parashar,
  Yang Shi"

* tag 'powerpc-4.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (214 commits)
  powerpc/64s: Power9 has no LPCR[VRMASD] field so don't set it
  powerpc/powernv: Fix TCE kill on NVLink2
  powerpc/mm/radix: Drop support for CPUs without lockless tlbie
  powerpc/book3s/mce: Move add_taint() later in virtual mode
  powerpc/sysfs: Move #ifdef CONFIG_HOTPLUG_CPU out of the function body
  powerpc/smp: Document irq enable/disable after migrating IRQs
  powerpc/mpc52xx: Don't select user-visible RTAS_PROC
  powerpc/powernv: Document cxl dependency on special case in pnv_eeh_reset()
  powerpc/eeh: Clean up and document event handling functions
  powerpc/eeh: Avoid use after free in eeh_handle_special_event()
  cxl: Mask slice error interrupts after first occurrence
  cxl: Route eeh events to all drivers in cxl_pci_error_detected()
  cxl: Force context lock during EEH flow
  powerpc/64: Allow CONFIG_RELOCATABLE if COMPILE_TEST
  powerpc/xmon: Teach xmon oops about radix vectors
  powerpc/mm/hash: Fix off-by-one in comment about kernel contexts ids
  powerpc/pseries: Enable VFIO
  powerpc/powernv: Fix iommu table size calculation hook for small tables
  powerpc/powernv: Check kzalloc() return value in pnv_pci_table_alloc
  powerpc: Add arch/powerpc/tools directory
  ...
2017-05-05 11:36:44 -07:00
Aneesh Kumar K.V 1b2fa5a046 powerpc/mm: Remove checks that TASK_SIZE_USER64 is too small
Remove the checks that TASK_SIZE_USER64 is smaller than H_PGTABLE_RANGE
and USER_VSID_RANGE.

In a following patch we will deliberately add support for a TASK_SIZE
smaller than both ranges, so this will no longer be an error condition.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Keep the check in pgtable_64.c that we don't exceed USER_VSID_RANGE]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-31 23:09:55 +11:00
Paul Mackerras fc36a90326 Revert "powerpc/64: Disable use of radix under a hypervisor"
This reverts commit 3f91a89d42.

Now that we do have the machinery for using the radix MMU under a
hypervisor, the extra check and comment introduced in 3f91a89d42 are
no longer correct.  The result is that when booted under a hypervisor
that only allows use of radix, we clear the MMU_FTR_TYPE_RADIX and
then set it again, and print a warning about ignoring the
disable_radix command line option, even though the command line does
not include "disable_radix".

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-21 16:50:28 +11:00
Suraj Jitindar Singh 014d02cbf1 powerpc: Update to new option-vector-5 format for CAS
On POWER9 the ibm,client-architecture-support (CAS) negotiation process
has been updated to change how the host to guest negotiation is done for
the new hash/radix mmu as well as the nest mmu, process tables and guest
translation shootdown (GTSE).

This is documented in the unreleased PAPR ACR "CAS option vector
additions for P9".

The host tells the guest which options it supports in
ibm,arch-vec-5-platform-support. The guest then chooses a subset of these
to request in the CAS call and these are agreed to in the
ibm,architecture-vec-5 property of the chosen node.

Thus we read ibm,arch-vec-5-platform-support and make our selection before
calling CAS. We then parse the ibm,architecture-vec-5 property of the
chosen node to check whether we should run as hash or radix.

ibm,arch-vec-5-platform-support format:

index value pairs: <index, val> ... <index, val>

index: Option vector 5 byte number
val:   Some representation of supported values

Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Acked-by: Paul Mackerras <paulus@ozlabs.org>
[mpe: Don't print about unknown options, be consistent with OV5_FEAT]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-06 21:44:09 +11:00
Linus Torvalds 38705613b7 powerpc updates for 4.11 part 1.
Highlights include:
 
  - Support for direct mapped LPC on POWER9, giving Linux direct access to
    devices that may be on there such as a UART.
 
  - Memory hotplug support for the Power9 Radix MMU.
 
  - Add new AUX vectors describing the processor's cache geometry, to be used by
    glibc.
 
  - The ability for a guest to ask the hypervisor to resize the guest's hash
    table, and in addition support for doing so automatically when memory is
    hotplugged into/out-of the guest. This allows the hash table to be sized
    based on the current memory usage of the guest, rather than the maximum
    possible memory usage.
 
  - Implementation of optprobes (kprobe optimisation) for powerpc.
 
 In addition there's the topic branch shared with the KVM tree, which includes
 support for guests to use the Radix MMU on Power9.
 
 Thanks to:
   Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T, Anton Blanchard,
   Benjamin Herrenschmidt, Chris Packham, Daniel Axtens, Daniel Borkmann, David
   Gibson, Finn Thain, Gautham R. Shenoy, Gavin Shan, Greg Kurz, Joel Stanley,
   John Allen, Madhavan Srinivasan, Mahesh Salgaonkar, Markus Elfring, Michael
   Neuling, Nathan Fontenot, Naveen N. Rao, Nicholas Piggin, Paul Mackerras, Ravi
   Bangoria, Reza Arbab, Shailendra Singh, Vaibhav Jain, Wei Yongjun.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJYrWj0AAoJEFHr6jzI4aWAsn4P/08Kz3TtOvDuuPGVNoO7fWOn
 ag5/zVt8R4FuCALqWpAZbVqMuUU4wLxG0RuWlmBNYYhrjMC6JxHpOSjQXxM2D7YT
 CdGTJxG414r6HMOeToL9i/z33o0m+KT07tscer+QMKlXVKCR2z0fEJch+zoPBHYA
 5eVBFpLLTtbNiX9UnrcM/vYz61d56kT4YJey9/8qbAkTAc1rMPa8ucU5UiKYJ7yX
 mF8cd7WE+7aqif9V8yN59G2rcbz+h3pbMw/gzImiYsYrUj4fLjU+VTKL5PPT+UFy
 WWBXD3MAMm1dksMMZi3hgoo2BZhDn3RkymeYi6Jo4kDknNMPZzkMxGyvaJ8Eq5H/
 bIYXdS1AbTtvaaEEuWqDFjpnChOEvj/8IeqitU0jjlql8BVjNKg/ESaaKucZr+pO
 pk2Mfvw0Tb/lxJT5qj27yq4aRsxJwdFOoPYCN7MquPp/wV2Tg5M6h4nVQ4T6Wl0S
 tMFQeCqXflhDWh0Xgr2UXpF66/YTj3Du5LasOTkgGeU30Z8TcNGFEmDWShKP3cEm
 e0oQE+OHhIGN4WSBXBAto/Gw8/0v3pXlMs+VEfeHqenwPss2sWtSwXWe8khmiy9e
 DJ48sTzj75/Zx1fiqRldw9YEnrL+NK0eOOpvzxeyKpfvdUytc+chFfEqUmO6kl3Z
 DW2UmlZxmW+b0SfexCHL
 =Icle
 -----END PGP SIGNATURE-----

Merge tag 'powerpc-4.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Highlights include:

   - Support for direct mapped LPC on POWER9, giving Linux direct access
     to devices that may be on there such as a UART.

   - Memory hotplug support for the Power9 Radix MMU.

   - Add new AUX vectors describing the processor's cache geometry, to
     be used by glibc.

   - The ability for a guest to ask the hypervisor to resize the guest's
     hash table, and in addition support for doing so automatically when
     memory is hotplugged into/out-of the guest. This allows the hash
     table to be sized based on the current memory usage of the guest,
     rather than the maximum possible memory usage.

   - Implementation of optprobes (kprobe optimisation) for powerpc.

  In addition there's the topic branch shared with the KVM tree, which
  includes support for guests to use the Radix MMU on Power9.

  Thanks to:
    Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T, Anton
    Blanchard, Benjamin Herrenschmidt, Chris Packham, Daniel Axtens,
    Daniel Borkmann, David Gibson, Finn Thain, Gautham R. Shenoy, Gavin
    Shan, Greg Kurz, Joel Stanley, John Allen, Madhavan Srinivasan,
    Mahesh Salgaonkar, Markus Elfring, Michael Neuling, Nathan Fontenot,
    Naveen N. Rao, Nicholas Piggin, Paul Mackerras, Ravi Bangoria, Reza
    Arbab, Shailendra Singh, Vaibhav Jain, Wei Yongjun"

* tag 'powerpc-4.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (129 commits)
  powerpc/mm/radix: Skip ptesync in pte update helpers
  powerpc/mm/radix: Use ptep_get_and_clear_full when clearing pte for full mm
  powerpc/mm/radix: Update pte update sequence for pte clear case
  powerpc/mm: Update PROTFAULT handling in the page fault path
  powerpc/xmon: Fix data-breakpoint
  powerpc/mm: Fix build break with BOOK3S_64=n and MEMORY_HOTPLUG=y
  powerpc/mm: Fix build break when CMA=n && SPAPR_TCE_IOMMU=y
  powerpc/mm: Fix build break with RADIX=y & HUGETLBFS=n
  powerpc/pseries: Fix typo in parameter description
  powerpc/kprobes: Remove kprobe_exceptions_notify()
  kprobes: Introduce weak variant of kprobe_exceptions_notify()
  powerpc/ftrace: Fix confusing help text for DISABLE_MPROFILE_KERNEL
  powerpc/powernv: Fix opal_exit tracepoint opcode
  powerpc: Add a prototype for mcount() so it can be versioned
  powerpc: Drop GPL from of_node_to_nid() export to match other arches
  powerpc/kprobes: Optimize kprobe in kretprobe_trampoline()
  powerpc/kprobes: Implement Optprobes
  powerpc/kprobes: Fixes for kprobe_lookup_name() on BE
  powerpc: Add helper to check if offset is within relative branch range
  powerpc/bpf: Introduce __PPC_SH64()
  ...
2017-02-22 10:30:38 -08:00
Paul Mackerras 3f91a89d42 powerpc/64: Disable use of radix under a hypervisor
Currently, if the kernel is running on a POWER9 processor under a
hypervisor, it may try to use the radix MMU even though it doesn't have
the necessary code to do so (it doesn't negotiate use of radix, and it
doesn't do the H_REGISTER_PROC_TBL hcall).  If the hypervisor supports
both radix and HPT, then it will set up the guest to use HPT (since the
guest doesn't request radix in the CAS call), but if the radix feature
bit is set in the ibm,pa-features property (which is valid, since
ibm,pa-features is defined to represent the capabilities of the
processor) the guest will try to use radix, resulting in a crash when
it turns the MMU on.

This makes the minimal fix for the current code, which is to disable
radix unless we are running in hypervisor mode.

Fixes: 2bfd65e45e ("powerpc/mm/radix: Add radix callbacks for early init routines")
Cc: stable@vger.kernel.org # v4.7+
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-02-16 14:01:42 +11:00
Paul Mackerras cc3d294013 powerpc/64: Enable use of radix MMU under hypervisor on POWER9
To use radix as a guest, we first need to tell the hypervisor via
the ibm,client-architecture call first that we support POWER9 and
architecture v3.00, and that we can do either radix or hash and
that we would like to choose later using an hcall (the
H_REGISTER_PROC_TBL hcall).

Then we need to check whether the hypervisor agreed to us using
radix.  We need to do this very early on in the kernel boot process
before any of the MMU initialization is done.  If the hypervisor
doesn't agree, we can't use radix and therefore clear the radix
MMU feature bit.

Later, when we have set up our process table, which points to the
radix tree for each process, we need to install that using the
H_REGISTER_PROC_TBL hcall.

Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:44 +11:00
Paul Mackerras 18569c1f13 powerpc/64: Don't try to use radix MMU under a hypervisor
Currently, if the kernel is running on a POWER9 processor under a
hypervisor, it will try to use the radix MMU even though it doesn't have
the necessary code to use radix under a hypervisor (it doesn't negotiate
use of radix, and it doesn't do the H_REGISTER_PROC_TBL hcall). The
result is that the guest kernel will crash when it tries to turn on the
MMU.

This fixes it by looking for the /chosen/ibm,architecture-vec-5
property, and if it exists, clears the radix MMU feature bit, before we
decide whether to initialize for radix or HPT. This property is created
by the hypervisor as a result of the guest calling the
ibm,client-architecture-support method to indicate its capabilities, so
it will indicate whether the hypervisor agreed to us using radix.

Systems without a hypervisor may have this property also (for example,
skiboot creates it), so we check the HV bit in the MSR to see whether we
are running as a guest or not. If we are in hypervisor mode, then we can
do whatever we like including using the radix MMU.

The reason for using this property is that in future, when we have
support for using radix under a hypervisor, we will need to check this
property to see whether the hypervisor agreed to us using radix.

Fixes: 2bfd65e45e ("powerpc/mm/radix: Add radix callbacks for early init routines")
Cc: stable@vger.kernel.org # v4.7+
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-01-31 19:11:43 +11:00
Linus Torvalds 7c0f6ba682 Replace <asm/uaccess.h> with <linux/uaccess.h> globally
This was entirely automated, using the script by Al:

  PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
  sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
        $(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-24 11:46:01 -08:00
Christophe Leroy 9b081e1080 powerpc: port 64 bits pgtable_cache to 32 bits
Today powerpc64 uses a set of pgtable_caches while powerpc32 uses
standard pages when using 4k pages and a single pgtable_cache
if using other size pages.

In preparation of implementing huge pages on the 8xx, this patch
replaces the specific powerpc32 handling by the 64 bits approach.

This is done by:
* moving 64 bits pgtable_cache_add() and pgtable_cache_init()
in a new file called init-common.c
* modifying pgtable_cache_init() to also handle the case
without PMD
* removing the 32 bits version of pgtable_cache_add() and
pgtable_cache_init()
* copying related header contents from 64 bits into both the
book3s/32 and nohash/32 header files

On the 8xx, the following cache sizes will be used:
* 4k pages mode:
- PGT_CACHE(10) for PGD
- PGT_CACHE(3) for 512k hugepage tables
* 16k pages mode:
- PGT_CACHE(6) for PGD
- PGT_CACHE(7) for 512k hugepage tables
- PGT_CACHE(3) for 8M hugepage tables

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Scott Wood <oss@buserror.net>
2016-12-09 22:48:01 -06:00
Aneesh Kumar K.V b8f1b4f860 powerpc/mm: Convert early cpu/mmu feature check to use the new helpers
This switches early feature checks to use the non static key variant of
the function. In later patches we will be switching cpu_has_feature()
and mmu_has_feature() to use static keys and we can use them only after
static key/jump label is initialized. Any check for feature before jump
label init should be done using this new helper.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:15:01 +10:00
Aneesh Kumar K.V 5a25b6f527 powerpc/mm: Make MMU_FTR_RADIX a MMU family feature
MMU feature bits are defined such that we use the lower half to
present MMU family features. Remove the strict split of half and
also move Radix to a mmu family feature. Radix introduce a new MMU
model and strictly speaking it is a new MMU family. This also free
up bits which can be used for individual features later.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:14:57 +10:00
Michael Ellerman 2537b09c93 powerpc/mm: Do radix device tree scanning earlier
Like we just did for hash, split the device tree scanning parts out and
call them from mmu_early_init_devtree().

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:14:55 +10:00
Michael Ellerman bacf9cf883 powerpc/mm: Do hash device tree scanning earlier
Currently MMU initialisation (early_init_mmu()) consists of a mixture of
scanning the device tree, setting MMU feature bits, and then also doing
actual initialisation of MMU data structures.

We'd like to decouple the setting of the MMU features from the actual
setup. So split out the device tree scanning, and associated code, and
call it from mmu_init_early_devtree().

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:14:54 +10:00
Michael Ellerman c610ec60ed powerpc/mm: Move disable_radix handling into mmu_early_init_devtree()
Move the handling of the disable_radix command line argument into the
newly created mmu_early_init_devtree().

It's an MMU option so it's preferable to have it in an mm related file,
and it also means platforms that don't support radix don't have to carry
the code.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:14:53 +10:00
Michael Ellerman 1a01dc87e0 powerpc/mm: Add mmu_early_init_devtree()
Empty for now, but we'll add to it in the next patch.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-08-01 11:14:53 +10:00
Aneesh Kumar K.V 31a14fae92 powerpc/mm: Abstraction for vmemmap and map_kernel_page()
For hash we create vmemmap mapping using bolted hash page table entries.
For radix we fill the radix page table. The next patch will add the
radix details for creating vmemmap mappings.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-01 18:33:02 +10:00
Aneesh Kumar K.V dd1842a2a4 powerpc/mm: Make page table size a variable
Radix and hash MMU models support different page table sizes. Make
the #defines a variable so that existing code can work with variable
sizes.

Slice related code is only used by hash, so use hash constants there. We
will replicate some of the boundary conditions with resepct to TASK_SIZE
using radix values too. Right now we do boundary condition check using
hash constants.

Swapper pgdir size is initialized in asm code. We select the max pgd
size to keep it simple. For now we select hash pgdir. When adding radix
we will switch that to radix pgdir which is 64K.

BUILD_BUG_ON check which is removed is already done in hugepage_init()
using MAYBE_BUILD_BUG_ON().

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-01 18:32:48 +10:00
Aneesh Kumar K.V eee24b5aaf powerpc/mm: Move hash and no hash code to separate files
This patch reduces the number of #ifdefs in C code and will also help in
adding radix changes later. Only code movement in this patch.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
[mpe: Propagate copyrights and update GPL text]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-01 18:32:42 +10:00
Aneesh Kumar K.V 368ced78e6 powerpc/mm: Switch book3s 64 with 64K page size to 4 level page table
This is needed so that we can support both hash and radix page table
using single kernel. Radix kernel uses a 4 level table.

We now use physical address in upper page table tree levels. Even though
they are aligned to their size, for the masked bits we use the
bit positions as per PowerISA 3.0.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-03 21:18:28 +11:00
David Gibson 1dace6c665 powerpc/mm: Clean up memory hotplug failure paths
This makes a number of cleanups to handling of mapping failures during
memory hotplug on Power:

For errors creating the linear mapping for the hot-added region:
  * This is now reported with EFAULT which is more appropriate than the
    previous EINVAL (the failure is unlikely to be related to the
    function's parameters)
  * An error in this path now prints a warning message, rather than just
    silently failing to add the extra memory.
  * Previously a failure here could result in the region being partially
    mapped.  We now clean up any partial mapping before failing.

For errors creating the vmemmap for the hot-added region:
   * This is now reported with EFAULT instead of causing a BUG() - this
     could happen for external reason (e.g. full hash table) so it's better
     to handle this non-fatally
   * An error message is also printed, so the failure won't be silent
   * As above a failure could cause a partially mapped region, we now
     clean this up. [mpe: move htab_remove_mapping() out of #ifdef
     CONFIG_MEMORY_HOTPLUG to enable this]

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Paul Mackerras <paulus@samba.org>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-01 22:04:18 +11:00
David Gibson 27828f98a0 powerpc/mm: Handle removing maybe-present bolted HPTEs
At the moment the hpte_removebolted callback in ppc_md returns void and
will BUG_ON() if the hpte it's asked to remove doesn't exist in the first
place.  This is awkward for the case of cleaning up a mapping which was
partially made before failing.

So, we add a return value to hpte_removebolted, and have it return ENOENT
in the case that the HPTE to remove didn't exist in the first place.

In the (sole) caller, we propagate errors in hpte_removebolted to its
caller to handle.  However, we handle ENOENT specially, continuing to
complete the unmapping over the specified range before returning the error
to the caller.

This means that htab_remove_mapping() will work sanely on a partially
present mapping, removing any HPTEs which are present, while also returning
ENOENT to its caller in case it's important there.

There are two callers of htab_remove_mapping():
   - In remove_section_mapping() we already WARN_ON() any error return,
     which is reasonable - in this case the mapping should be fully
     present
   - In vmemmap_remove_mapping() we BUG_ON() any error.  We change that to
     just a WARN_ON() in the case of ENOENT, since failing to remove a
     mapping that wasn't there in the first place probably shouldn't be
     fatal.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-03-01 22:04:18 +11:00
Aneesh Kumar K.V 62607bc64c powerpc/mm: Don't hardcode page table size
pte and pmd table size are dependent on config items. Don't
hard code the same. This make sure we use the right value
when masking pmd entries and also while checking pmd_bad

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14 15:19:15 +11:00
Yanjiang Jin e77553cb21 powerpc/mm: Free string after creating kmem cache
kmem_cache_create()->kmem_cache_create_memcg()->kstrdup() allocates new
space and copys name's content, so it is safe to free name memory after
calling kmem_cache_create(). Else kmemleak will report the below
warning:

unreferenced object 0xc0000000f9002160 (size 16):
  comm "swapper/0", pid 0, jiffies 4294892296 (age 1386.640s)
  hex dump (first 16 bytes):
    70 67 74 61 62 6c 65 2d 32 5e 39 00 de ad be ef  pgtable-2^9.....
  backtrace:
    [<c0000000004e03ec>] .kvasprintf+0x5c/0xa0
    [<c0000000004e045c>] .kasprintf+0x2c/0x50
    [<c00000000002e36c>] .pgtable_cache_add+0xac/0x100
    [<c00000000002e3e4>] .pgtable_cache_init+0x24/0x80
    [<c000000000c6c67c>] .start_kernel+0x228/0x4c8
    [<c000000000000594>] .start_here_common+0x24/0x90

Signed-off-by: Yanjiang Jin <yanjiang.jin@windriver.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-03-26 15:23:17 +11:00
Anton Blanchard 68cf0d642f powerpc: Remove superfluous bootmem includes
Lots of places included bootmem.h even when not using bootmem.

Signed-off-by: Anton Blanchard <anton@samba.org>
Tested-by: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-11-10 09:59:26 +11:00
Anton Blanchard f6026df1a4 powerpc: Move htab_remove_mapping function prototype into header file
A recent patch added a function prototype for htab_remove_mapping in
c code. Fix it.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2014-09-25 23:14:44 +10:00
Li Zhong 16a05bff12 powerpc: start loop at section start of start in vmemmap_populated()
vmemmap_populated() checks whether the [start, start + page_size) has valid
pfn numbers, to know whether a vmemmap mapping has been created that includes
this range.

Some range before end might not be checked by this loop:
  sec11start......start11..sec11end/sec12start..end....start12..sec12end
as the above, for start11(section 11), it checks [sec11start, sec11end), and
loop ends as the next start(start12) is bigger than end. However,
[sec11end/sec12start, end) is not checked here.

So before the loop, adjust the start to be the start of the section, so we don't miss ranges like the above.

After we adjust start to be the start of the section, it also means it's
aligned with vmemmap as of the sizeof struct page, so we could use
page_to_pfn directly in the loop.

Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05 16:34:23 +10:00
Li Zhong 71b0bfe4f1 powerpc: implement vmemmap_free()
vmemmap_free() does the opposite of vmemap_populate().
This patch also puts vmemmap_free() and vmemmap_list_free() into
 CONFIG_MEMMORY_HOTPLUG.

Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05 16:34:19 +10:00
Li Zhong ed5694a846 powerpc: implement vmemmap_remove_mapping() for BOOK3S
This is to be called in vmemmap_free(), leave the implementation on BOOK3E
empty as before.

Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05 16:34:15 +10:00
Li Zhong bd8cb03dbe powerpc: implement vmemmap_list_free()
This patch implements vmemmap_list_free() for vmemmap_free().

The freed entries will be removed from vmemmap_list, and form a freed list,
with next as the header. The next position in the last allocated page is kept
at the list tail.

When allocation, if there are freed entries left, get it from the freed list;
if no freed entries left, get it like before from the last allocated pages.

With this change, realmode_pfn_to_page() also needs to be changed to walk
all the entries in the vmemmap_list, as the virt_addr of the entries might not
be stored in order anymore.

It helps to reuse the memory when continuous doing memory hot-plug/remove
operations, but didn't reclaim the pages already allocated, so the memory usage
will only increase, but won't exceed the value for the largest memory
configuration.

Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Acked-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2014-08-05 16:34:10 +10:00
Alexey Kardashevskiy 8e0861fa3c powerpc: Prepare to support kernel handling of IOMMU map/unmap
The current VFIO-on-POWER implementation supports only user mode
driven mapping, i.e. QEMU is sending requests to map/unmap pages.
However this approach is really slow, so we want to move that to KVM.
Since H_PUT_TCE can be extremely performance sensitive (especially with
network adapters where each packet needs to be mapped/unmapped) we chose
to implement that as a "fast" hypercall directly in "real
mode" (processor still in the guest context but MMU off).

To be able to do that, we need to provide some facilities to
access the struct page count within that real mode environment as things
like the sparsemem vmemmap mappings aren't accessible.

This adds an API function realmode_pfn_to_page() to get page struct when
MMU is off.

This adds to MM a new function put_page_unless_one() which drops a page
if counter is bigger than 1. It is going to be used when MMU is off
(for example, real mode on PPC64) and we want to make sure that page
release will not happen in real mode as it may crash the kernel in
a horrible way.

CONFIG_SPARSEMEM_VMEMMAP and CONFIG_FLATMEM are supported.

Cc: linux-mm@kvack.org
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-10-11 17:24:39 +11:00
Nathan Fontenot f7e3334a6b powerpc: Fix memory hotplug with sparse vmemmap
Previous commit 46723bfa540... introduced a new config option
HAVE_BOOTMEM_INFO_NODE that ended up breaking memory hot-remove for ppc
when sparse vmemmap is not defined.

This patch defines HAVE_BOOTMEM_INFO_NODE for ppc and adds the call to
register_page_bootmem_info_node. Without this we get a BUG_ON for memory
hot remove in put_page_bootmem().

This also adds a stub for register_page_bootmem_memmap to allow ppc to build
with sparse vmemmap defined. Leaving this as a stub is fine since the same
vmemmap addresses are also handled in vmemmap_populate and as such are
properly mapped.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: <stable@vger.kernel.org> [v3.9+]
2013-10-03 17:21:38 +10:00