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2016-01-15powerpc, thp: remove infrastructure for handling splitting PMDsKirill A. Shutemov
With new refcounting we don't need to mark PMDs splitting. Let's drop code to handle this. pmdp_splitting_flush() is not needed too: on splitting PMD we will do pmdp_clear_flush() + set_pte_at(). pmdp_clear_flush() will do IPI as needed for fast_gup. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Cc: Sasha Levin <sasha.levin@oracle.com> Cc: Jerome Marchand <jmarchan@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Steve Capper <steve.capper@linaro.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15mm: drop tail page refcountingKirill A. Shutemov
Tail page refcounting is utterly complicated and painful to support. It uses ->_mapcount on tail pages to store how many times this page is pinned. get_page() bumps ->_mapcount on tail page in addition to ->_count on head. This information is required by split_huge_page() to be able to distribute pins from head of compound page to tails during the split. We will need ->_mapcount to account PTE mappings of subpages of the compound page. We eliminate need in current meaning of ->_mapcount in tail pages by forbidding split entirely if the page is pinned. The only user of tail page refcounting is THP which is marked BROKEN for now. Let's drop all this mess. It makes get_page() and put_page() much simpler. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Tested-by: Sasha Levin <sasha.levin@oracle.com> Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Jerome Marchand <jmarchan@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Steve Capper <steve.capper@linaro.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15thp: rename split_huge_page_pmd() to split_huge_pmd()Kirill A. Shutemov
We are going to decouple splitting THP PMD from splitting underlying compound page. This patch renames split_huge_page_pmd*() functions to split_huge_pmd*() to reflect the fact that it doesn't imply page splitting, only PMD. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Tested-by: Sasha Levin <sasha.levin@oracle.com> Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Acked-by: Jerome Marchand <jmarchan@redhat.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: Steve Capper <steve.capper@linaro.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@suse.cz> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-14Merge branch 'next' of ↵Michael Ellerman
git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux into next Freescale updates from Scott: "Highlights include moving QE code out of arch/powerpc (to be shared with arm), device tree updates, and minor fixes."
2016-01-09powerpc: Fix build break due to paca mm_context_t changesMichael Ellerman
Commit 2fc251a8dda5 ("powerpc: Copy only required pieces of the mm_context_t to the paca") broke the build for CONFIG_PPC_STD_MMU_64=y and CONFIG_PPC_MM_SLICES=n. That only happens for a kernel built with 4K pages and HUGETLB disabled, which is why we missed it. Fix it by adding a mm_ctx_user_psize member to the paca and populating it in the appropriate places. Fixes: 2fc251a8dda5 ("powerpc: Copy only required pieces of the mm_context_t to the paca") Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-27powerpc: Copy only required pieces of the mm_context_t to the pacaMichael Neuling
Currently we copy the whole mm_context_t to the paca but only access a few bits of it. This is wasteful of space paca and also takes quite some time in the hot path of context switching. This patch pulls in only the required bits from the mm_context_t to the paca and on context switch, copies only those. Benchmarking this (On top of Anton's recent MSR context switching changes [1]) using processes and yield shows an improvement of almost 3% on POWER8: http://ozlabs.org/~anton/junkcode/context_switch2.c ./context_switch2 --test=yield --process 0 0 1. https://lists.ozlabs.org/pipermail/linuxppc-dev/2015-October/135700.html Signed-off-by: Michael Neuling <mikey@neuling.org> [mpe: Rename paca fields to be mm_ctx_foo rather than context_foo] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-22powerpc/e6500: add locking to hugetlbScott Wood
e6500 has threads but does not have TLB write conditional. Thus, the hugetlb code needs to take the same lock that the normal TLB miss handlers take, to ensure that the tlbsx and tlbwe are atomic. Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-12-19powerpc: Add function to copy mm_context_t to the pacaMichael Neuling
This adds a function to copy the mm->context to the paca. This is only a basic conversion for now but will be used more extensively in the next patch. This also adds #ifdef CONFIG_PPC_BOOK3S around this code since it's not used elsewhere. Signed-off-by: Michael Neuling <mikey@neuling.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14powerpc/mm: Don't open code pgtable_t sizeAneesh Kumar K.V
The slot information of base page size hash pte is stored in the pgtable_t w.r.t transparent hugepage. We need to make sure we don't index beyond pgtable_t size. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14powerpc/mm: Don't hardcode page table sizeAneesh Kumar K.V
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>
2015-12-14powerpc/mm: Add a _PAGE_PTE bitAneesh Kumar K.V
For a pte entry we will have _PAGE_PTE set. Our pte page address have a minimum alignment requirement of HUGEPD_SHIFT_MASK + 1. We use the lower 7 bits to indicate hugepd. ie. For pmd and pgd we can find: 1) _PAGE_PTE set pte -> indicate PTE 2) bits [2..6] non zero -> indicate hugepd. They also encode the size. We skip bit 1 (_PAGE_PRESENT). 3) othewise pointer to next table. Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14powerpc/mm: Move THP headers aroundAneesh Kumar K.V
We support THP only with book3s_64 and 64K page size. Move THP details to hash64-64k.h to clarify the same. Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14powerpc/mm: Move hugetlb related headersAneesh Kumar K.V
W.r.t hugetlb, we support two format for pmd. With book3s_64 and 64K linux page size, we can have pte at the pmd level. Hence we don't need to support hugepd there. For everything else hugepd is supported and pmd_huge is (0). Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14powerpc/mm: Move WIMG update to helper.Aneesh Kumar K.V
Only difference here is, we apply the WIMG mapping early, so rflags passed to updatepp will also be changed. Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14powerpc/mm: Add helper for converting pte bit to hpte bitsAneesh Kumar K.V
Instead of open coding it in multiple code paths, export the helper and add more documentation. Also make sure we don't make assumption regarding pte bit position Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14powerpc/mm: Convert 4k insert from asm to CAneesh Kumar K.V
This is similar to 64K insert. May be we want to consolidate Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14powerpc/mm: Convert __hash_page_64K to CAneesh Kumar K.V
Convert from asm to C Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14powerpc/mm: Remove pte_val usage for the second half of pgtable_tAneesh Kumar K.V
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14powerpc/mm: Don't track subpage valid bit in pte_tAneesh Kumar K.V
This free up 11 bits in pte_t. In the later patch we also change the pte_t format so that we can start supporting migration pte at pmd level. We now track 4k subpage valid bit as below If we have _PAGE_COMBO set, we override the _PAGE_F_GIX_SHIFT and _PAGE_F_SECOND. Together we have 4 bits, each of them used to indicate whether any of the 4 4k subpage in that group is valid. ie, [ group 1 bit ] [ group 2 bit ] ..... [ group 4 ] [ subpage 1 - 4] [ subpage 5- 8] ..... [ subpage 13 - 16] We still track each 4k subpage slot number and secondary hash information in the second half of pgtable_t. Removing the subpage tracking have some significant overhead on aim9 and ebizzy benchmark and to support THP with 4K subpage, we do need a pgtable_t of 4096 bytes. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14powerpc/mm: Remove the dependency on pte bit position in asm codeAneesh Kumar K.V
We should not expect pte bit position in asm code. Simply by moving part of that to C Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14powerpc/mm: Convert 4k hash insert to CAneesh Kumar K.V
Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14powerpc/mm: Don't use pmd_val, pud_val and pgd_val as lvalueAneesh Kumar K.V
We convert them static inline function here as we did with pte_val in the previous patch Acked-by: Scott Wood <scottwood@freescale.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-12-14powerpc/mm: Fix infinite loop in hash fault with 4K page sizeAneesh Kumar K.V
This is the same bug we fixed as part of 09567e7fd44291bfc08accfdd67ad8f467842332 ("powerpc/mm: Check paca psize is up to date for huge mappings"). Please check that for details. The difference here is that faults were happening on a 4K page at an address previously mapped by hugetlb. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-11-05Merge tag 'powerpc-4.4-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: - Kconfig: remove BE-only platforms from LE kernel build from Boqun Feng - Refresh ps3_defconfig from Geoff Levand - Emit GNU & SysV hashes for the vdso from Michael Ellerman - Define an enum for the bolted SLB indexes from Anshuman Khandual - Use a local to avoid multiple calls to get_slb_shadow() from Michael Ellerman - Add gettimeofday() benchmark from Michael Neuling - Avoid link stack corruption in __get_datapage() from Michael Neuling - Add virt_to_pfn and use this instead of opencoding from Aneesh Kumar K.V - Add ppc64le_defconfig from Michael Ellerman - pseries: extract of_helpers module from Andy Shevchenko - Correct string length in pseries_of_derive_parent() from Nathan Fontenot - Free the MSI bitmap if it was slab allocated from Denis Kirjanov - Shorten irq_chip name for the SIU from Christophe Leroy - Wait 1s for secondaries to enter OPAL during kexec from Samuel Mendoza-Jonas - Fix _ALIGN_* errors due to type difference, from Aneesh Kumar K.V - powerpc/pseries/hvcserver: don't memset pi_buff if it is null from Colin Ian King - Disable hugepd for 64K page size, from Aneesh Kumar K.V - Differentiate between hugetlb and THP during page walk from Aneesh Kumar K.V - Make PCI non-optional for pseries from Michael Ellerman - Individual System V IPC system calls from Sam bobroff - Add selftest of unmuxed IPC calls from Michael Ellerman - discard .exit.data at runtime from Stephen Rothwell - Delete old orphaned PrPMC 280/2800 DTS and boot file, from Paul Gortmaker - Use of_get_next_parent to simplify code from Christophe Jaillet - Paginate some xmon output from Sam bobroff - Add some more elements to the xmon PACA dump from Michael Ellerman - Allow the tm-syscall selftest to build with old headers from Michael Ellerman - Run EBB selftests only on POWER8 from Denis Kirjanov - Drop CONFIG_TUNE_CELL in favour of CONFIG_CELL_CPU from Michael Ellerman - Avoid reference to potentially freed memory in prom.c from Christophe Jaillet - Quieten boot wrapper output with run_cmd from Geoff Levand - EEH fixes and cleanups from Gavin Shan - Fix recursive fenced PHB on Broadcom shiner adapter from Gavin Shan - Use of_get_next_parent() in of_get_ibm_chip_id() from Michael Ellerman - Fix section mismatch warning in msi_bitmap_alloc() from Denis Kirjanov - Fix ps3-lpm white space from Rudhresh Kumar J - Fix ps3-vuart null dereference from Colin King - nvram: Add missing kfree in error path from Christophe Jaillet - nvram: Fix function name in some errors messages, from Christophe Jaillet - drivers/macintosh: adb: fix misleading Kconfig help text from Aaro Koskinen - agp/uninorth: fix a memleak in create_gatt_table from Denis Kirjanov - cxl: Free virtual PHB when removing from Andrew Donnellan - scripts/kconfig/Makefile: Allow KBUILD_DEFCONFIG to be a target from Michael Ellerman - scripts/kconfig/Makefile: Fix KBUILD_DEFCONFIG check when building with O= from Michael Ellerman - Freescale updates from Scott: Highlights include 64-bit book3e kexec/kdump support, a rework of the qoriq clock driver, device tree changes including qoriq fman nodes, support for a new 85xx board, and some fixes. - MPC5xxx updates from Anatolij: Highlights include a driver for MPC512x LocalPlus Bus FIFO with its device tree binding documentation, mpc512x device tree updates and some minor fixes. * tag 'powerpc-4.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (106 commits) powerpc/msi: Fix section mismatch warning in msi_bitmap_alloc() powerpc/prom: Use of_get_next_parent() in of_get_ibm_chip_id() powerpc/pseries: Correct string length in pseries_of_derive_parent() powerpc/e6500: hw tablewalk: make sure we invalidate and write to the same tlb entry powerpc/mpc85xx: Add FSL QorIQ DPAA FMan support to the SoC device tree(s) powerpc/mpc85xx: Create dts components for the FSL QorIQ DPAA FMan powerpc/fsl: Add #clock-cells and clockgen label to clockgen nodes powerpc: handle error case in cpm_muram_alloc() powerpc: mpic: use IRQCHIP_SKIP_SET_WAKE instead of redundant mpic_irq_set_wake powerpc/book3e-64: Enable kexec powerpc/book3e-64/kexec: Set "r4 = 0" when entering spinloop powerpc/booke: Only use VIRT_PHYS_OFFSET on booke32 powerpc/book3e-64/kexec: Enable SMP release powerpc/book3e-64/kexec: create an identity TLB mapping powerpc/book3e-64: Don't limit paca to 256 MiB powerpc/book3e/kdump: Enable crash_kexec_wait_realmode powerpc/book3e: support CONFIG_RELOCATABLE powerpc/booke64: Fix args to copy_and_flush powerpc/book3e-64: rename interrupt_end_book3e with __end_interrupts powerpc/e6500: kexec: Handle hardware threads ...
2015-11-05arch/powerpc/mm/numa.c: do not allocate bootmem memory for non existing nodesRaghavendra K T
With the setup_nr_nodes(), we have already initialized node_possible_map. So it is safe to use for_each_node here. There are many places in the kernel that use hardcoded 'for' loop with nr_node_ids, because all other architectures have numa nodes populated serially. That should be reason we had maintained the same for powerpc. But, since sparse numa node ids possible on powerpc, we unnecessarily allocate memory for non existent numa nodes. For e.g., on a system with 0,1,16,17 as numa nodes nr_node_ids=18 and we allocate memory for nodes 2-14. This patch we allocate memory for only existing numa nodes. The patch is boot tested on a 4 node tuleta, confirming with printks that it works as expected. Signed-off-by: Raghavendra K T <raghavendra.kt@linux.vnet.ibm.com> Cc: Vladimir Davydov <vdavydov@parallels.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Anton Blanchard <anton@samba.org> Cc: Nishanth Aravamudan <nacc@linux.vnet.ibm.com> Cc: Greg Kurz <gkurz@linux.vnet.ibm.com> Cc: Grant Likely <grant.likely@linaro.org> Cc: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-10-27powerpc/e6500: hw tablewalk: make sure we invalidate and write to the same ↵Kevin Hao
tlb entry In order to workaround Erratum A-008139, we have to invalidate the tlb entry with tlbilx before overwriting. Due to the performance consideration, we don't add any memory barrier when acquire/release the tcd lock. This means the two load instructions for esel_next do have the possibility to return different value. This is definitely not acceptable due to the Erratum A-008139. We have two options to fix this issue: a) Add memory barrier when acquire/release tcd lock to order the load/store to esel_next. b) Just make sure to invalidate and write to the same tlb entry and tolerate the race that we may get the wrong value and overwrite the tlb entry just updated by the other thread. We observe better performance using option b. So reserve an additional register to save the value of the esel_next. Signed-off-by: Kevin Hao <haokexin@gmail.com> Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-10-27powerpc/fsl-booke-64: Don't limit ppc64_rma_size to one TLB entryScott Wood
This is required for kdump to work when loaded at at an address that does not fall within the first TLB entry -- which can easily happen because while the lower limit is enforced via reserved memory, which doesn't affect how much is mapped, the upper limit is enforced via a different mechanism that does. Thus, more TLB entries are needed than would normally be used, as the total memory to be mapped might not be a power of two. Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-10-22powerpc/85xx: Load all early TLB entries at onceScott Wood
Use an AS=1 trampoline TLB entry to allow all normal TLB1 entries to be loaded at once. This avoids the need to keep the translation that code is executing from in the same TLB entry in the final TLB configuration as during early boot, which in turn is helpful for relocatable kernels (e.g. kdump) where the kernel is not running from what would be the first TLB entry. On e6500, we limit map_mem_in_cams() to the primary hwthread of a core (the boot cpu is always considered primary, as a kdump kernel can be entered on any cpu). Each TLB only needs to be set up once, and when we do, we don't want another thread to be running when we create a temporary trampoline TLB1 entry. Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-10-15powerpc/numa: Use of_get_next_parent to simplify codeChristophe Jaillet
of_get_next_parent can be used to simplify the while() loop and avoid the need of a temp variable. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-12powerpc/mm: Differentiate between hugetlb and THP during page walkAneesh Kumar K.V
We need to properly identify whether a hugepage is an explicit or a transparent hugepage in follow_huge_addr(). We used to depend on hugepage shift argument to do that. But in some case that can result in wrong results. For ex: On finding a transparent hugepage we set hugepage shift to PMD_SHIFT. But we can end up clearing the thp pte, via pmdp_huge_get_and_clear. We do prevent reusing the pfn page via the usage of kick_all_cpus_sync(). But that happens after we updated the pte to 0. Hence in follow_huge_addr() we can find hugepage shift set, but transparent huge page check fail for a thp pte. NOTE: We fixed a variant of this race against thp split in commit 691e95fd7396905a38d98919e9c150dbc3ea21a3 ("powerpc/mm/thp: Make page table walk safe against thp split/collapse") Without this patch, we may hit the BUG_ON(flags & FOLL_GET) in follow_page_mask occasionally. In the long term, we may want to switch ppc64 64k page size config to enable CONFIG_ARCH_WANT_GENERAL_HUGETLB Reported-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-12powerpc/mm: Disable hugepd for 64K page size.Aneesh Kumar K.V
After commit e2b3d202d1dba8f3546ed28224ce485bc50010be ("powerpc: Switch 16GB and 16MB explicit hugepages to a different page table format"), we don't need to support is_hugepd() for 64K page size. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-09powerpc: Fix checkstop in native_hpte_clear() with lockdepCyril Bur
native_hpte_clear() is called in real mode from two places: - Early in boot during htab initialisation if firmware assisted dump is active. - Late in the kexec path. In both contexts there is no need to disable interrupts are they are already disabled. Furthermore, locking around the tlbie() is only required for pre POWER5 hardware. On POWER5 or newer hardware concurrent tlbie()s work as expected and on pre POWER5 hardware concurrent tlbie()s could result in deadlock. This code would only be executed at crashdump time, during which all bets are off, concurrent tlbie()s are unlikely and taking locks is unsafe therefore the best course of action is to simply do nothing. Concurrent tlbie()s are not possible in the first case as secondary CPUs have not come up yet. Signed-off-by: Cyril Bur <cyrilbur@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-01powerpc/slb: Use a local to avoid multiple calls to get_slb_shadow()Michael Ellerman
For no reason other than it looks ugly. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-10-01powerpc/slb: Define an enum for the bolted indexesAnshuman Khandual
This patch defines macros for the three bolted SLB indexes we use. Switch the functions that take the indexes as an argument to use the enum. Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-09-18Merge tag 'powerpc-4.3-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc fixes from Michael Ellerman: - Fix 32-bit TCE table init in kdump kernel from Nish - Fix kdump with non-power-of-2 crashkernel= from Nish - Abort cxl_pci_enable_device_hook() if PCI channel is offline from Andrew - Fix to release DRC when configure_connector() fails from Bharata - Wire up sys_userfaultfd() - Fix race condition in tearing down MSI interrupts from Paul - Fix unbalanced pci_dev_get() in cxl_probe() from Daniel - Fix cxl build failure due to -Wunused-variable gcc behaviour change from Ian - Tell the toolchain to use ABI v2 when building an LE boot wrapper from Benh - Fix THP to recompute hash value after a failed update from Aneesh - 32-bit memcpy/memset: only use dcbz once cache is enabled from Christophe * tag 'powerpc-4.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: powerpc32: memset: only use dcbz once cache is enabled powerpc32: memcpy: only use dcbz once cache is enabled powerpc/mm: Recompute hash value after a failed update powerpc/boot: Specify ABI v2 when building an LE boot wrapper cxl: Fix build failure due to -Wunused-variable behaviour change cxl: Fix unbalanced pci_dev_get in cxl_probe powerpc/MSI: Fix race condition in tearing down MSI interrupts powerpc: Wire up sys_userfaultfd() powerpc/pseries: Release DRC when configure_connector fails cxl: abort cxl_pci_enable_device_hook() if PCI channel is offline powerpc/powernv/pci-ioda: fix kdump with non-power-of-2 crashkernel= powerpc/powernv/pci-ioda: fix 32-bit TCE table init in kdump kernel
2015-09-16powerpc/mm: Recompute hash value after a failed updateAneesh Kumar K.V
If we had secondary hash flag set, we ended up modifying hash value in the updatepp code path. Hence with a failed updatepp we will be using a wrong hash value for the following hash insert. Fix this by recomputing hash before insert. Without this patch we can end up with using wrong slot number in linux pte. That can result in us missing an hash pte update or invalidate which can cause memory corruption or even machine check. Fixes: 6d492ecc6489 ("powerpc/THP: Add code to handle HPTE faults for hugepages") Cc: stable@vger.kernel.org # v3.11+ Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Paul Mackerras <paulus@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-09-08Merge tag 'libnvdimm-for-4.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm Pull libnvdimm updates from Dan Williams: "This update has successfully completed a 0day-kbuild run and has appeared in a linux-next release. The changes outside of the typical drivers/nvdimm/ and drivers/acpi/nfit.[ch] paths are related to the removal of IORESOURCE_CACHEABLE, the introduction of memremap(), and the introduction of ZONE_DEVICE + devm_memremap_pages(). Summary: - Introduce ZONE_DEVICE and devm_memremap_pages() as a generic mechanism for adding device-driver-discovered memory regions to the kernel's direct map. This facility is used by the pmem driver to enable pfn_to_page() operations on the page frames returned by DAX ('direct_access' in 'struct block_device_operations'). For now, the 'memmap' allocation for these "device" pages comes from "System RAM". Support for allocating the memmap from device memory will arrive in a later kernel. - Introduce memremap() to replace usages of ioremap_cache() and ioremap_wt(). memremap() drops the __iomem annotation for these mappings to memory that do not have i/o side effects. The replacement of ioremap_cache() with memremap() is limited to the pmem driver to ease merging the api change in v4.3. Completion of the conversion is targeted for v4.4. - Similar to the usage of memcpy_to_pmem() + wmb_pmem() in the pmem driver, update the VFS DAX implementation and PMEM api to provide persistence guarantees for kernel operations on a DAX mapping. - Convert the ACPI NFIT 'BLK' driver to map the block apertures as cacheable to improve performance. - Miscellaneous updates and fixes to libnvdimm including support for issuing "address range scrub" commands, clarifying the optimal 'sector size' of pmem devices, a clarification of the usage of the ACPI '_STA' (status) property for DIMM devices, and other minor fixes" * tag 'libnvdimm-for-4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (34 commits) libnvdimm, pmem: direct map legacy pmem by default libnvdimm, pmem: 'struct page' for pmem libnvdimm, pfn: 'struct page' provider infrastructure x86, pmem: clarify that ARCH_HAS_PMEM_API implies PMEM mapped WB add devm_memremap_pages mm: ZONE_DEVICE for "device memory" mm: move __phys_to_pfn and __pfn_to_phys to asm/generic/memory_model.h dax: drop size parameter to ->direct_access() nd_blk: change aperture mapping from WC to WB nvdimm: change to use generic kvfree() pmem, dax: have direct_access use __pmem annotation dax: update I/O path to do proper PMEM flushing pmem: add copy_from_iter_pmem() and clear_pmem() pmem, x86: clean up conditional pmem includes pmem: remove layer when calling arch_has_wmb_pmem() pmem, x86: move x86 PMEM API to new pmem.h header libnvdimm, e820: make CONFIG_X86_PMEM_LEGACY a tristate option pmem: switch to devm_ allocations devres: add devm_memremap libnvdimm, btt: write and validate parent_uuid ...
2015-08-27mm: ZONE_DEVICE for "device memory"Dan Williams
While pmem is usable as a block device or via DAX mappings to userspace there are several usage scenarios that can not target pmem due to its lack of struct page coverage. In preparation for "hot plugging" pmem into the vmemmap add ZONE_DEVICE as a new zone to tag these pages separately from the ones that are subject to standard page allocations. Importantly "device memory" can be removed at will by userspace unbinding the driver of the device. Having a separate zone prevents allocation and otherwise marks these pages that are distinct from typical uniform memory. Device memory has different lifetime and performance characteristics than RAM. However, since we have run out of ZONES_SHIFT bits this functionality currently depends on sacrificing ZONE_DMA. Cc: H. Peter Anvin <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Jerome Glisse <j.glisse@gmail.com> [hch: various simplifications in the arch interface] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2015-08-27Merge branch 'next' of ↵Michael Ellerman
git://git.kernel.org/pub/scm/linux/kernel/git/scottwood/linux into next Freescale updates from Scott: "Highlights include 32-bit memcpy/memset optimizations, checksum optimizations, 85xx config fragments and updates, device tree updates, e6500 fixes for non-SMP, and misc cleanup and minor fixes."
2015-08-18powerpc/numa: initialize distance lookup table from drconf pathNikunj A Dadhania
In some situations, a NUMA guest that supports ibm,dynamic-memory-reconfiguration node will end up having flat NUMA distances between nodes. This is because of two problems in the current code. 1) Different representations of associativity lists. There is an assumption about the associativity list in initialize_distance_lookup_table(). Associativity list has two forms: a) [cpu,memory]@x/ibm,associativity has following format: <N> <N integers> b) ibm,dynamic-reconfiguration-memory/ibm,associativity-lookup-arrays <M> <N> <M associativity lists each having N integers> M = the number of associativity lists N = the number of entries per associativity list Fix initialize_distance_lookup_table() so that it does not assume "case a". And update the caller to skip the length field before sending the associativity list. 2) Distance table not getting updated from drconf path. Node distance table will not get initialized in certain cases as ibm,dynamic-reconfiguration-memory path does not initialize the lookup table. Call initialize_distance_lookup_table() from drconf path with appropriate associativity list. Reported-by: Bharata B Rao <bharata@linux.vnet.ibm.com> Signed-off-by: Nikunj A Dadhania <nikunj@linux.vnet.ibm.com> Acked-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-08-18powerpc/mm: Drop CONFIG_PPC_HAS_HASH_64KMichael Ellerman
The relation between CONFIG_PPC_HAS_HASH_64K and CONFIG_PPC_64K_PAGES is painfully complicated. But if we rearrange it enough we can see that PPC_HAS_HASH_64K essentially depends on PPC_STD_MMU_64 && PPC_64K_PAGES. We can then notice that PPC_HAS_HASH_64K is used in files that are only built for PPC_STD_MMU_64, meaning it's equivalent to PPC_64K_PAGES. So replace all uses and drop it. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
2015-08-18powerpc/cell: Drop support for 64K local store on 4K kernelsMichael Ellerman
Back in the olden days we added support for using 64K pages to map the SPU (Synergistic Processing Unit) local store on Cell, when the main kernel was using 4K pages. This was useful at the time because distros were using 4K pages, but using 64K pages on the SPUs could reduce TLB pressure there. However these days the number of Cell users is approaching zero, and supporting this option adds unpleasant complexity to the memory management code. So drop the option, CONFIG_SPU_FS_64K_LS, and all related code. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Jeremy Kerr <jk@ozlabs.org>
2015-08-17powerpc/e6500: hw tablewalk: optimize a bit for tcd lock acquiring codesKevin Hao
It makes no sense to put the instructions for calculating the lock value (cpu number + 1) and the clearing of eq bit of cr1 in lbarx/stbcx loop. And when the lock is acquired by the other thread, the current lock value has no chance to equal with the lock value used by current cpu. So we can skip the comparing for these two lock values in the lbz/bne loop. Signed-off-by: Kevin Hao <haokexin@gmail.com> Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-08-12powerpc/slb: Add documentation on runtime patching of SLB encodingAnshuman Khandual
This patch adds some documentation to patch_slb_encoding() explaining how it works. Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> [mpe: Update change log and mention the signedness of the immediate] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-08-12powerpc/slb: Rename all the 'slot' occurrences to 'entry'Anshuman Khandual
The SLB code uses 'slot' and 'entry' interchangeably, change it to always use 'entry'. Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> [mpe: Rewrite change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-08-12powerpc/slb: Remove a duplicate extern variableAnshuman Khandual
This patch just removes one redundant entry for one extern variable 'slb_compare_rr_to_size' from the scope. This patch does not change any functionality. Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2015-08-07powerpc/fsl: Force coherent memory on e500mc derivativesScott Wood
In CoreNet systems it is not allowed to mix M and non-M mappings to the same memory, and coherent DMA accesses are considered to be M mappings for this purpose. Ignoring this has been observed to cause hard lockups in non-SMP kernels on e6500. Furthermore, e6500 implements the LRAT (logical to real address table) which allows KVM guests to control the WIMGE bits. This means that KVM cannot force the M bit on the way it usually does, so the guest had better set it itself. Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-08-07powerpc/booke64: Move mb() to __set_pte_at() with kernel-addr testScott Wood
map_kernel() doesn't catch all places that create kernel PTEs. In particular, vmalloc() calls set_pte_at() directly. This causes a crash when booting a non-SMP kernel on e6500. Move the sync to __set_pte(), to be executed only for kernel addresses. Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-08-07powerpc/mm: Don't call __flush_dcache_icache_phys() with PA>VAScott Wood
__flush_dcache_icache_phys() requires the ability to access the memory with the MMU disabled, which means that on a 32-bit system any memory above 4 GiB is inaccessible. In particular, mpc86xx is 32-bit and can have more than 4 GiB of RAM. Signed-off-by: Scott Wood <scottwood@freescale.com>
2015-07-06powerpc: Add plain English description for alignment exception oopsesAnton Blanchard
If we take an alignment exception which we cannot fix, the oops currently prints: Unable to handle kernel paging request for unknown fault Lets print something more useful: Unable to handle kernel paging request for unaligned access at address 0xc0000000f77bba8f Signed-off-by: Anton Blanchard <anton@samba.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>