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2024-03-06mm/treewide: replace pud_large() with pud_leaf()Peter Xu
pud_large() is always defined as pud_leaf(). Merge their usages. Chose pud_leaf() because pud_leaf() is a global API, while pud_large() is not. Link: https://lkml.kernel.org/r/20240305043750.93762-9-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Muchun Song <muchun.song@linux.dev> Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Yang Shi <shy828301@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-03-06mm/treewide: replace pmd_large() with pmd_leaf()Peter Xu
pmd_large() is always defined as pmd_leaf(). Merge their usages. Chose pmd_leaf() because pmd_leaf() is a global API, while pmd_large() is not. Link: https://lkml.kernel.org/r/20240305043750.93762-8-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Alexander Potapenko <glider@google.com> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: "Aneesh Kumar K.V" <aneesh.kumar@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Muchun Song <muchun.song@linux.dev> Cc: "Naveen N. Rao" <naveen.n.rao@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Yang Shi <shy828301@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-09-19s390/ctlreg: add struct ctlregHeiko Carstens
Add struct ctlreg to enforce strict type checking / usage for control register functions. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-09-07Merge tag 's390-6.6-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux Pull more s390 updates from Heiko Carstens: - A couple of virtual vs physical address confusion fixes - Rework locking in dcssblk driver to address a lockdep warning - Remove support for "noexec" kernel command line option since there is no use case where it would make sense - Simplify kernel mapping setup and get rid of quite a bit of code - Add architecture specific __set_memory_yy() functions which allow us to modify kernel mappings. Unlike the set_memory_xx() variants they take void pointer start and end parameters, which allows using them without the usual casts, and also to use them on areas larger than 8TB. Note that the set_memory_xx() family comes with an int num_pages parameter which overflows with 8TB. This could be addressed by changing the num_pages parameter to unsigned long, however requires to change all architectures, since the module code expects an int parameter (see module_set_memory()). This was indeed an issue since for debug_pagealloc() we call set_memory_4k() on the whole identity mapping. Therefore address this for now with the __set_memory_yy() variant, and address common code later - Use dev_set_name() and also fix memory leak in zcrypt driver error handling - Remove unused lsi_mask from airq_struct - Add warning for invalid kernel mapping requests * tag 's390-6.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: s390/vmem: do not silently ignore mapping limit s390/zcrypt: utilize dev_set_name() ability to use a formatted string s390/zcrypt: don't leak memory if dev_set_name() fails s390/mm: fix MAX_DMA_ADDRESS physical vs virtual confusion s390/airq: remove lsi_mask from airq_struct s390/mm: use __set_memory() variants where useful s390/set_memory: add __set_memory() variant s390/set_memory: generate all set_memory() functions s390/mm: improve description of mapping permissions of prefix pages s390/amode31: change type of __samode31, __eamode31, etc s390/mm: simplify kernel mapping setup s390: remove "noexec" option s390/vmem: fix virtual vs physical address confusion s390/dcssblk: fix lockdep warning s390/monreader: fix virtual vs physical address confusion
2023-08-30s390/set_memory: add __set_memory() variantHeiko Carstens
Add a __set_memory_yy() variant for all set_memory_yy() implementations. The new variant takes start and end void pointers, which allows them to be used without the usual unsigned long cast. However more important: the new variant can be used for areas larger than 8TB. The old variant comes with an "int numpages" parameter, which overflows with more than 8TB. Given that for debug_pagealloc set_memory_4k() is used on the whole kernel mapping this is not only a theoretical problem, but must be fixed. Changing all set_memory_yy() variants only on s390 to take an "unsigned long numpages" parameter is not possible, since the common module code requires an int parameter from all architectures on these functions. See module_set_memory(). Therefore change/fix this on s390 only with a new interface, and address common code later. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2023-07-11mm: Move pte/pmd_mkwrite() callers with no VMA to _novma()Rick Edgecombe
The x86 Shadow stack feature includes a new type of memory called shadow stack. This shadow stack memory has some unusual properties, which requires some core mm changes to function properly. One of these unusual properties is that shadow stack memory is writable, but only in limited ways. These limits are applied via a specific PTE bit combination. Nevertheless, the memory is writable, and core mm code will need to apply the writable permissions in the typical paths that call pte_mkwrite(). Future patches will make pte_mkwrite() take a VMA, so that the x86 implementation of it can know whether to create regular writable or shadow stack mappings. But there are a couple of challenges to this. Modifying the signatures of each arch pte_mkwrite() implementation would be error prone because some are generated with macros and would need to be re-implemented. Also, some pte_mkwrite() callers operate on kernel memory without a VMA. So this can be done in a three step process. First pte_mkwrite() can be renamed to pte_mkwrite_novma() in each arch, with a generic pte_mkwrite() added that just calls pte_mkwrite_novma(). Next callers without a VMA can be moved to pte_mkwrite_novma(). And lastly, pte_mkwrite() and all callers can be changed to take/pass a VMA. Earlier work did the first step, so next move the callers that don't have a VMA to pte_mkwrite_novma(). Also do the same for pmd_mkwrite(). This will be ok for the shadow stack feature, as these callers are on kernel memory which will not need to be made shadow stack, and the other architectures only currently support one type of memory in pte_mkwrite() Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com> Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/all/20230613001108.3040476-3-rick.p.edgecombe%40intel.com
2023-05-17procfs: consolidate arch_report_meminfo declarationArnd Bergmann
The arch_report_meminfo() function is provided by four architectures, with a __weak fallback in procfs itself. On architectures that don't have a custom version, the __weak version causes a warning because of the missing prototype. Remove the architecture specific prototypes and instead add one in linux/proc_fs.h. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> # for arch/x86 Acked-by: Helge Deller <deller@gmx.de> # parisc Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Message-Id: <20230516195834.551901-1-arnd@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2023-04-20s390/mm: use VM_FLUSH_RESET_PERMS in module_alloc()Heiko Carstens
Make use of the set_direct_map() calls for module allocations. In particular: - All changes to read-only permissions in kernel VA mappings are also applied to the direct mapping. Note that execute permissions are intentionally not applied to the direct mapping in order to make sure that all allocated pages within the direct mapping stay non-executable - module_alloc() passes the VM_FLUSH_RESET_PERMS to __vmalloc_node_range() to make sure that all implicit permission changes made to the direct mapping are reset when the allocated vm area is freed again Side effects: the direct mapping will be fragmented depending on how many vm areas with VM_FLUSH_RESET_PERMS and/or explicit page permission changes are allocated and freed again. For example, just after boot of a system the direct mapping statistics look like: $cat /proc/meminfo ... DirectMap4k: 111628 kB DirectMap1M: 16665600 kB DirectMap2G: 0 kB Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-04-20s390/mm: enable ARCH_HAS_SET_DIRECT_MAPHeiko Carstens
Implement the set_direct_map_*() API, which allows to invalidate and set default permissions to pages within the direct mapping. Note that kernel_page_present(), which is also supposed to be part of this API, is intentionally not implemented. The reason for this is that kernel_page_present() is only used (and currently only makes sense) for suspend/resume, which isn't supported on s390. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-04-13s390/mm: fix direct map accountingHeiko Carstens
Commit bb1520d581a3 ("s390/mm: start kernel with DAT enabled") did not implement direct map accounting in the early page table setup code. In result the reported values are bogus now: $cat /proc/meminfo ... DirectMap4k: 5120 kB DirectMap1M: 18446744073709546496 kB DirectMap2G: 0 kB Fix this by adding the missing accounting. The result looks sane again: $cat /proc/meminfo ... DirectMap4k: 6156 kB DirectMap1M: 2091008 kB DirectMap2G: 6291456 kB Fixes: bb1520d581a3 ("s390/mm: start kernel with DAT enabled") Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2023-03-20s390/mm,pageattr: allow KASAN shadow memoryVasily Gorbik
Allow changing page table attributes for KASAN shadow memory ranges. Acked-by: Heiko Carstens <hca@linux.ibm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2022-03-01s390/mm,pageattr: don't use pte_val()/pXd_val() as lvalueHeiko Carstens
Convert pgtable code so pte_val()/pXd_val() aren't used as lvalue anymore. This allows in later step to convert pte_val()/pXd_val() to functions, which in turn makes it impossible to use these macros to modify page table entries like they have been used before. Therefore a construct like this: pte_val(*pte) = __pa(addr) | prot; which would directly write into a page table, isn't possible anymore with the last step of this series. Reviewed-by: Claudio Imbrenda <imbrenda@linux.ibm.com> Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2022-03-01s390/mm: use set_pXd()/set_pte() helper functions everywhereHeiko Carstens
Use the new set_pXd()/set_pte() helper functions at all places where page table entries are modified. Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-10-26s390/pgtable: use physical address for Page-Table OriginAlexander Gordeev
Instructions IPTE, IDTE and CRDTE accept Page-Table Origin as one of the arguments, but instead the pgtable virtual address is passed. Fix that and also update the crdte() prototype to conform to csp() and cspg() friends. Reviewed-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2021-08-25s390/mm,pageattr: fix walk_pte_level() early exitHeiko Carstens
In case of splitting to 4k mapping the early exit in walk_pte_level() must only be taken iff flags is equal to SET_MEMORY_4K. Currently the early exit is taken if the flag is set, and also others might be set. This may lead to the situation that a mapping is split but other changes are not done, like e.g. setting pages to R/W. There is currently no such caller, but there might be in the future. Fixes: b3e1a00c8fa4 ("s390/mm: implement set_memory_4k()") Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-08-05s390/mm: use page_to_virt() in __kernel_map_pages()Heiko Carstens
Fix virtual vs physical address confusion (which currently are the same). Reviewed-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-07-30s390: add support for KFENCESven Schnelle
Signed-off-by: Sven Schnelle <svens@linux.ibm.com> [hca@linux.ibm.com: simplify/rework code] Link: https://lore.kernel.org/r/20210728190254.3921642-4-hca@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2021-07-30s390/mm: implement set_memory_4k()Heiko Carstens
Implement set_memory_4k() which will split any present large or huge mapping in the given range to a 4k mapping. Link: https://lore.kernel.org/r/20210728190254.3921642-2-hca@linux.ibm.com Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
2020-09-14s390/mm,ptdump: hold cpa mutex while walking for kernel page table dumpHeiko Carstens
This is currently only preventing that outdated information is provided to user space. A concurrent split of huge/large pages does modify the kernel page tables, however either the huge/large mapping is reported or the split area is being walked. This "fixes" also only a potential future bug, since split pages could also be merged again if page permissions are the same for larger memory areas. Reviewed-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2020-06-09mm: consolidate pte_index() and pte_offset_*() definitionsMike Rapoport
All architectures define pte_index() as (address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1) and all architectures define pte_offset_kernel() as an entry in the array of PTEs indexed by the pte_index(). For the most architectures the pte_offset_kernel() implementation relies on the availability of pmd_page_vaddr() that converts a PMD entry value to the virtual address of the page containing PTEs array. Let's move x86 definitions of the PTE accessors to the generic place in <linux/pgtable.h> and then simply drop the respective definitions from the other architectures. The architectures that didn't provide pmd_page_vaddr() are updated to have that defined. The generic implementation of pte_offset_kernel() can be overridden by an architecture and alpha makes use of this because it has special ordering requirements for its version of pte_offset_kernel(). [rppt@linux.ibm.com: v2] Link: http://lkml.kernel.org/r/20200514170327.31389-11-rppt@kernel.org [rppt@linux.ibm.com: update] Link: http://lkml.kernel.org/r/20200514170327.31389-12-rppt@kernel.org [rppt@linux.ibm.com: update] Link: http://lkml.kernel.org/r/20200514170327.31389-13-rppt@kernel.org [akpm@linux-foundation.org: fix x86 warning] [sfr@canb.auug.org.au: fix powerpc build] Link: http://lkml.kernel.org/r/20200607153443.GB738695@linux.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200514170327.31389-10-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09mm: pgtable: add shortcuts for accessing kernel PMD and PTEMike Rapoport
The powerpc 32-bit implementation of pgtable has nice shortcuts for accessing kernel PMD and PTE for a given virtual address. Make these helpers available for all architectures. [rppt@linux.ibm.com: microblaze: fix page table traversal in setup_rt_frame()] Link: http://lkml.kernel.org/r/20200518191511.GD1118872@kernel.org [akpm@linux-foundation.org: s/pmd_ptr_k/pmd_off_k/ in various powerpc places] Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200514170327.31389-9-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09mm: don't include asm/pgtable.h if linux/mm.h is already includedMike Rapoport
Patch series "mm: consolidate definitions of page table accessors", v2. The low level page table accessors (pXY_index(), pXY_offset()) are duplicated across all architectures and sometimes more than once. For instance, we have 31 definition of pgd_offset() for 25 supported architectures. Most of these definitions are actually identical and typically it boils down to, e.g. static inline unsigned long pmd_index(unsigned long address) { return (address >> PMD_SHIFT) & (PTRS_PER_PMD - 1); } static inline pmd_t *pmd_offset(pud_t *pud, unsigned long address) { return (pmd_t *)pud_page_vaddr(*pud) + pmd_index(address); } These definitions can be shared among 90% of the arches provided XYZ_SHIFT, PTRS_PER_XYZ and xyz_page_vaddr() are defined. For architectures that really need a custom version there is always possibility to override the generic version with the usual ifdefs magic. These patches introduce include/linux/pgtable.h that replaces include/asm-generic/pgtable.h and add the definitions of the page table accessors to the new header. This patch (of 12): The linux/mm.h header includes <asm/pgtable.h> to allow inlining of the functions involving page table manipulations, e.g. pte_alloc() and pmd_alloc(). So, there is no point to explicitly include <asm/pgtable.h> in the files that include <linux/mm.h>. The include statements in such cases are remove with a simple loop: for f in $(git grep -l "include <linux/mm.h>") ; do sed -i -e '/include <asm\/pgtable.h>/ d' $f done Signed-off-by: Mike Rapoport <rppt@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Cain <bcain@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Ungerer <gerg@linux-m68k.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Guo Ren <guoren@kernel.org> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Helge Deller <deller@gmx.de> Cc: Ingo Molnar <mingo@redhat.com> Cc: Ley Foon Tan <ley.foon.tan@intel.com> Cc: Mark Salter <msalter@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Mike Rapoport <rppt@kernel.org> Cc: Nick Hu <nickhu@andestech.com> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Stafford Horne <shorne@gmail.com> Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Will Deacon <will@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200514170327.31389-1-rppt@kernel.org Link: http://lkml.kernel.org/r/20200514170327.31389-2-rppt@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-03-23s390: remove broken hibernate / power management supportHeiko Carstens
Hibernation is known to be broken for many years on s390. Given that there aren't any real use cases, remove the code instead of spending time to fix and maintain it. Without hibernate support it doesn't make too much sense to keep power management support; therefore remove it completely. Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
2018-07-30s390/mm: Clear huge page storage keys on enable_skeyDominik Dingel
When a guest starts using storage keys, we trap and set a default one for its whole valid address space. With this patch we are now able to do that for large pages. To speed up the storage key insertion, we use __storage_key_init_range, which in-turn will use sske_frame to set multiple storage keys with one instruction. As it has been previously used for debuging we have to get rid of the default key check and make it quiescing. Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com> [replaced page_set_storage_key loop with __storage_key_init_range] Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Reviewed-by: David Hildenbrand <david@redhat.com>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-07-26s390/mm,vmem: simplify region and segment table allocation codeHeiko Carstens
Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Reviewed-by: Janosch Frank <frankja@linux.vnet.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-07-25s390/mm: add guest ASCE TLB flush optimizationMartin Schwidefsky
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-07-25s390/mm: add no-dat TLB flush optimizationMartin Schwidefsky
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-06-12s390/mm: implement 5 level pages tablesMartin Schwidefsky
Add the logic to upgrade the page table for a 64-bit process to five levels. This increases the TASK_SIZE from 8PB to 16EB-4K. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-05-08s390: use set_memory.h headerLaura Abbott
set_memory_* functions have moved to set_memory.h. Switch to this explicitly Link: http://lkml.kernel.org/r/1488920133-27229-5-git-send-email-labbott@redhat.com Signed-off-by: Laura Abbott <labbott@redhat.com> Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-26s390/pageattr: avoid unnecessary page table splittingHeiko Carstens
The kernel page table splitting code will split page tables even for features the CPU does not support. E.g. a CPU may not support the NX feature. In order to avoid this, remove those bits from the flags parameter that correlate with unsupported CPU features within __set_memory(). In addition add an early exit if the flags parameter does not have any bits set afterwards. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-02-17s390: mm: Audit and remove any unnecessary uses of module.hPaul Gortmaker
Historically a lot of these existed because we did not have a distinction between what was modular code and what was providing support to modules via EXPORT_SYMBOL and friends. That changed when we forked out support for the latter into the export.h file. This means we should be able to reduce the usage of module.h in code that is obj-y Makefile or bool Kconfig. The advantage in doing so is that module.h itself sources about 15 other headers; adding significantly to what we feed cpp, and it can obscure what headers we are effectively using. Since module.h was the source for init.h (for __init) and for export.h (for EXPORT_SYMBOL) we consider each change instance for the presence of either and replace as needed. An instance where module_param was used without moduleparam.h was also fixed, as well as an implict use of asm/elf.h header. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2017-02-08s390: add no-execute supportMartin Schwidefsky
Bit 0x100 of a page table, segment table of region table entry can be used to disallow code execution for the virtual addresses associated with the entry. There is one tricky bit, the system call to return from a signal is part of the signal frame written to the user stack. With a non-executable stack this would stop working. To avoid breaking things the protection fault handler checks the opcode that caused the fault for 0x0a77 (sys_sigreturn) and 0x0aad (sys_rt_sigreturn) and injects a system call. This is preferable to the alternative solution with a stub function in the vdso because it works for vdso=off and statically linked binaries as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-08-24s390/mm: merge local / non-local IPTE helperMartin Schwidefsky
Merge the __ptep_ipte and __ptep_ipte_local functions into a single __ptep_ipte function with an additional parameter. The __pte_ipte_range function is still extra as the while loops makes it hard to merge. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-08-10s390/pageattr: handle numpages parameter correctlyHeiko Carstens
Both set_memory_ro() and set_memory_rw() will modify the page attributes of at least one page, even if the numpages parameter is zero. The author expected that calling these functions with numpages == zero would never happen. However with the new 444d13ff10fb ("modules: add ro_after_init support") feature this happens frequently. Therefore do the right thing and make these two functions return gracefully if nothing should be done. Fixes crashes on module load like this one: Unable to handle kernel pointer dereference in virtual kernel address space Failing address: 000003ff80008000 TEID: 000003ff80008407 Fault in home space mode while using kernel ASCE. AS:0000000000d18007 R3:00000001e6aa4007 S:00000001e6a10800 P:00000001e34ee21d Oops: 0004 ilc:3 [#1] SMP Modules linked in: x_tables CPU: 10 PID: 1 Comm: systemd Not tainted 4.7.0-11895-g3fa9045 #4 Hardware name: IBM 2964 N96 703 (LPAR) task: 00000001e9118000 task.stack: 00000001e9120000 Krnl PSW : 0704e00180000000 00000000005677f8 (rb_erase+0xf0/0x4d0) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 000003ff80008b20 000003ff80008b20 000003ff80008b70 0000000000b9d608 000003ff80008b20 0000000000000000 00000001e9123e88 000003ff80008950 00000001e485ab40 000003ff00000000 000003ff80008b00 00000001e4858480 0000000100000000 000003ff80008b68 00000000001d5998 00000001e9123c28 Krnl Code: 00000000005677e8: ec1801c3007c cgij %r1,0,8,567b6e 00000000005677ee: e32010100020 cg %r2,16(%r1) #00000000005677f4: a78401c2 brc 8,567b78 >00000000005677f8: e35010080024 stg %r5,8(%r1) 00000000005677fe: ec5801af007c cgij %r5,0,8,567b5c 0000000000567804: e30050000024 stg %r0,0(%r5) 000000000056780a: ebacf0680004 lmg %r10,%r12,104(%r15) 0000000000567810: 07fe bcr 15,%r14 Call Trace: ([<000003ff80008900>] __this_module+0x0/0xffffffffffffd700 [x_tables]) ([<0000000000264fd4>] do_init_module+0x12c/0x220) ([<00000000001da14a>] load_module+0x24e2/0x2b10) ([<00000000001da976>] SyS_finit_module+0xbe/0xd8) ([<0000000000803b26>] system_call+0xd6/0x264) Last Breaking-Event-Address: [<000000000056771a>] rb_erase+0x12/0x4d0 Kernel panic - not syncing: Fatal exception: panic_on_oops Reported-by: Christian Borntraeger <borntraeger@de.ibm.com> Reported-and-tested-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Fixes: e8a97e42dc98 ("s390/pageattr: allow kernel page table splitting") Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-14s390/mm: fix compile for PAGE_DEFAULT_KEY != 0Heiko Carstens
The usual problem for code that is ifdef'ed out is that it doesn't compile after a while. That's also the case for the storage key initialisation code, if it would be used (set PAGE_DEFAULT_KEY to something not zero): ./arch/s390/include/asm/page.h: In function 'storage_key_init_range': ./arch/s390/include/asm/page.h:36:2: error: implicit declaration of function '__storage_key_init_range' Since the code itself has been useful for debugging purposes several times, remove the ifdefs and make sure the code gets compiler coverage. The cost for this is eight bytes. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-13s390/pgtable: add mapping statisticsHeiko Carstens
Add statistics that show how memory is mapped within the kernel identity mapping. This is more or less the same like git commit ce0c0e50f94e ("x86, generic: CPA add statistics about state of direct mapping v4") for x86. I also intentionally copied the lower case "k" within DirectMap4k vs the upper case "M" and "G" within the two other lines. Let's have consistent inconsistencies across architectures. The output of /proc/meminfo now contains these additional lines: DirectMap4k: 2048 kB DirectMap1M: 3991552 kB DirectMap2G: 4194304 kB The implementation on s390 is lockless unlike the x86 version, since I assume changes to the kernel mapping are a very rare event. Therefore it really doesn't matter if these statistics could potentially be inconsistent if read while kernel pages tables are being changed. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-13s390/pageattr: allow kernel page table splittingHeiko Carstens
set_memory_ro() and set_memory_rw() currently only work on 4k mappings, which is good enough for module code aka the vmalloc area. However we stumbled already twice into the need to make this also work on larger mappings: - the ro after init patch set - the crash kernel resize code Therefore this patch implements automatic kernel page table splitting if e.g. set_memory_ro() would be called on parts of a 2G mapping. This works quite the same as the x86 code, but is much simpler. In order to make this work and to be architecturally compliant we now always use the csp, cspg or crdte instructions to replace valid page table entries. This means that set_memory_ro() and set_memory_rw() will be much more expensive than before. In order to avoid huge latencies the code contains a couple of cond_resched() calls. The current code only splits page tables, but does not merge them if it would be possible. The reason for this is that currently there is no real life scenarion where this would really happen. All current use cases that I know of only change access rights once during the life time. If that should change we can still implement kernel page table merging at a later time. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-13s390/mm: always use PAGE_KERNEL when mapping pagesHeiko Carstens
Always use PAGE_KERNEL when re-enabling pages within the kernel mapping due to debug pagealloc. Without using this pgprot value pte_mkwrite() and pte_wrprotect() won't work on such mappings after an unmap -> map cycle anymore. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-02-23s390/pageattr: do a single TLB flush for change_page_attrMartin Schwidefsky
The change of the access rights for an address range in the kernel address space is currently done with a loop of IPTE + a store of the modified PTE. Between the IPTE and the store the PTE will be invalid, this intermediate state can cause problems with concurrent accesses. Consider a change of a kernel area from read-write to read-only, a concurrent reader of that area should be fine but with the invalid PTE it might get an unexpected exception. Remove the IPTEs for each PTE and do a global flush after all PTEs have been modified. Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-03-25s390: remove 31 bit supportHeiko Carstens
Remove the 31 bit support in order to reduce maintenance cost and effectively remove dead code. Since a couple of years there is no distribution left that comes with a 31 bit kernel. The 31 bit kernel also has been broken since more than a year before anybody noticed. In addition I added a removal warning to the kernel shown at ipl for 5 minutes: a960062e5826 ("s390: add 31 bit warning message") which let everybody know about the plan to remove 31 bit code. We didn't get any response. Given that the last 31 bit only machine was introduced in 1999 let's remove the code. Anybody with 31 bit user space code can still use the compat mode. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-12-13mm/debug-pagealloc: make debug-pagealloc boottime configurableJoonsoo Kim
Now, we have prepared to avoid using debug-pagealloc in boottime. So introduce new kernel-parameter to disable debug-pagealloc in boottime, and makes related functions to be disabled in this case. Only non-intuitive part is change of guard page functions. Because guard page is effective only if debug-pagealloc is enabled, turning off according to debug-pagealloc is reasonable thing to do. Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Dave Hansen <dave@sr71.net> Cc: Michal Nazarewicz <mina86@mina86.com> Cc: Jungsoo Son <jungsoo.son@lge.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-09-30s390/mm: make use of ipte range facilityHeiko Carstens
Invalidate several pte entries at once if the ipte range facility is available. Currently this works only for DEBUG_PAGE_ALLOC where several up to 2 ^ MAX_ORDER may be invalidated at once. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-10-24s390/mm: do not initialize storage keysMartin Schwidefsky
With dirty and referenced bits implemented in software it is unnecessary to initialize the storage key for every page. With this patch not a single storage key operation is done for a system that does not use KVM. For KVM set_pte_at/pgste_set_key will do the initialization for the guest view of the storage key when the mapping for the page is established in the host. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-08-22s390/mm: cleanup page table definitionsMartin Schwidefsky
Improve the encoding of the different pte types and the naming of the page, segment table and region table bits. Due to the different pte encoding the hugetlbfs primitives need to be adapted as well. To improve compatability with common code make the huge ptes use the encoding of normal ptes. The conversion between the pte and pmd encoding for a huge pte is done with set_huge_pte_at and huge_ptep_get. Overall the code is now easier to understand. Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-04-17s390/mm: speedup storage key initializationHeiko Carstens
Use sske with multiple block control to initialize storage keys within a 1 MB frame at once. It turned out that the sske with mb=1 is an order of magnitude faster than pfmf. This is only an issue for very large systems (several 100GB) where storage key initialization could last more than a minute. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-02-14s390/mm: implement software dirty bitsMartin Schwidefsky
The s390 architecture is unique in respect to dirty page detection, it uses the change bit in the per-page storage key to track page modifications. All other architectures track dirty bits by means of page table entries. This property of s390 has caused numerous problems in the past, e.g. see git commit ef5d437f71afdf4a "mm: fix XFS oops due to dirty pages without buffers on s390". To avoid future issues in regard to per-page dirty bits convert s390 to a fault based software dirty bit detection mechanism. All user page table entries which are marked as clean will be hardware read-only, even if the pte is supposed to be writable. A write by the user process will trigger a protection fault which will cause the user pte to be marked as dirty and the hardware read-only bit is removed. With this change the dirty bit in the storage key is irrelevant for Linux as a host, but the storage key is still required for KVM guests. The effect is that page_test_and_clear_dirty and the related code can be removed. The referenced bit in the storage key is still used by the page_test_and_clear_young primitive to provide page age information. For page cache pages of mappings with mapping_cap_account_dirty there will not be any change in behavior as the dirty bit tracking already uses read-only ptes to control the amount of dirty pages. Only for swap cache pages and pages of mappings without mapping_cap_account_dirty there can be additional protection faults. To avoid an excessive number of additional faults the mk_pte primitive checks for PageDirty if the pgprot value allows for writes and pre-dirties the pte. That avoids all additional faults for tmpfs and shmem pages until these pages are added to the swap cache. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-11-23s390/mm: move kernel_page_present/kernel_map_pages to page_attr.cHeiko Carstens
Keep related functions together and move to appropriate file. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-11-23s390/memory hotplug: use pfmf instruction to initialize storage keysHeiko Carstens
Move and rename init_storage_keys() to pageattr.c, so it can also be used from the sclp memory hotplug code in order to initialize storage keys. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2012-11-23s390/mm,vmem: use 2GB frames for identity mappingHeiko Carstens
Use 2GB frames for indentity mapping if EDAT2 is available to reduce TLB pressure. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>