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2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156Thomas Gleixner1-14/+1
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1334 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-03powerpc/mm: define subarch SLB_ADDR_LIMIT_DEFAULTChristophe Leroy1-5/+1
This patch defines a subarch specific SLB_ADDR_LIMIT_DEFAULT to remove the #ifdefs around the setup of mm->context.slb_addr_limit It also generalises the use of mm_ctx_set_slb_addr_limit() helper. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03powerpc/mm: remove a couple of #ifdef CONFIG_PPC_64K_PAGES in mm/slice.cChristophe Leroy1-6/+4
This patch replaces a couple of #ifdef CONFIG_PPC_64K_PAGES by IS_ENABLED(CONFIG_PPC_64K_PAGES) to improve code maintainability. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03powerpc/mm: remove unnecessary #ifdef CONFIG_PPC64Christophe Leroy1-3/+1
For PPC32 that's a noop, gcc should be smart enough to ignore it. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03powerpc/mm: move slice_mask_for_size() into mmu.hChristophe Leroy1-34/+0
Move slice_mask_for_size() into subarch mmu.h Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> [mpe: Retain the BUG_ON()s, rather than converting to VM_BUG_ON()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-05-03powerpc/mm: hand a context_t over to slice_mask_for_size() instead of mm_structChristophe Leroy1-17/+17
slice_mask_for_size() only uses mm->context, so hand directly a pointer to the context. This will help moving the function in subarch mmu.h in the next patch by avoiding having to include the definition of struct mm_struct Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-04-21powerpc/mm: Add helpers for accessing hash translation related variablesAneesh Kumar K.V1-25/+24
We want to switch to allocating them runtime only when hash translation is enabled. Add helpers so that both book3s and nohash can be adapted to upcoming change easily. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2019-02-26powerpc/mm/hash: Handle mmap_min_addr correctly in get_unmapped_area topdown ↵Aneesh Kumar K.V1-4/+6
search When doing top-down search the low_limit is not PAGE_SIZE but rather max(PAGE_SIZE, mmap_min_addr). This handle cases in which mmap_min_addr > PAGE_SIZE. Fixes: fba2369e6ceb ("mm: use vm_unmapped_area() on powerpc architecture") Reviewed-by: Laurent Dufour <ldufour@linux.vnet.ibm.com> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-20powerpc/mm: fix always true/false warning in slice.cChristophe Leroy1-7/+14
This patch fixes the following warnings (obtained with make W=1). arch/powerpc/mm/slice.c: In function 'slice_range_to_mask': arch/powerpc/mm/slice.c:73:12: error: comparison is always true due to limited range of data type [-Werror=type-limits] if (start < SLICE_LOW_TOP) { ^ arch/powerpc/mm/slice.c:81:20: error: comparison is always false due to limited range of data type [-Werror=type-limits] if ((start + len) > SLICE_LOW_TOP) { ^ arch/powerpc/mm/slice.c: In function 'slice_mask_for_free': arch/powerpc/mm/slice.c:136:17: error: comparison is always true due to limited range of data type [-Werror=type-limits] if (high_limit <= SLICE_LOW_TOP) ^ arch/powerpc/mm/slice.c: In function 'slice_check_range_fits': arch/powerpc/mm/slice.c:185:12: error: comparison is always true due to limited range of data type [-Werror=type-limits] if (start < SLICE_LOW_TOP) { ^ arch/powerpc/mm/slice.c:195:39: error: comparison is always false due to limited range of data type [-Werror=type-limits] if (SLICE_NUM_HIGH && ((start + len) > SLICE_LOW_TOP)) { ^ arch/powerpc/mm/slice.c: In function 'slice_scan_available': arch/powerpc/mm/slice.c:306:11: error: comparison is always true due to limited range of data type [-Werror=type-limits] if (addr < SLICE_LOW_TOP) { ^ arch/powerpc/mm/slice.c: In function 'get_slice_psize': arch/powerpc/mm/slice.c:709:11: error: comparison is always true due to limited range of data type [-Werror=type-limits] if (addr < SLICE_LOW_TOP) { ^ Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-20powerpc/mm: fix missing prototypes in slice.cChristophe Leroy1-0/+1
This patch fixes the following warnings (obtained with make W=1). arch/powerpc/mm/slice.c: At top level: arch/powerpc/mm/slice.c:682:15: error: no previous prototype for 'arch_get_unmapped_area' [-Werror=missing-prototypes] unsigned long arch_get_unmapped_area(struct file *filp, ^ arch/powerpc/mm/slice.c:692:15: error: no previous prototype for 'arch_get_unmapped_area_topdown' [-Werror=missing-prototypes] unsigned long arch_get_unmapped_area_topdown(struct file *filp, ^ Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14powerpc/64s/hash: Simplify slb_flush_and_rebolt()Nicholas Piggin1-1/+1
slb_flush_and_rebolt() is misleading, it is called in virtual mode, so it can not possibly change the stack, so it should not be touching the shadow area. And since vmalloc is no longer bolted, it should not change any bolted mappings at all. Change the name to slb_flush_and_restore_bolted(), and have it just load the kernel stack from what's currently in the shadow SLB area. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-14powerpc/64s/hash: Provide arch_setup_exec() hooks for hash slice setupNicholas Piggin1-0/+14
This will be used by the SLB code in the next patch, but for now this sets the slb_addr_limit to the correct size for 32-bit tasks. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-03Revert "convert SLB miss handlers to C" and subsequent commitsMichael Ellerman1-23/+20
This reverts commits: 5e46e29e6a97 ("powerpc/64s/hash: convert SLB miss handlers to C") 8fed04d0f6ae ("powerpc/64s/hash: remove user SLB data from the paca") 655deecf67b2 ("powerpc/64s/hash: SLB allocation status bitmaps") 2e1626744e8d ("powerpc/64s/hash: provide arch_setup_exec hooks for hash slice setup") 89ca4e126a3f ("powerpc/64s/hash: Add a SLB preload cache") This series had a few bugs, and the fixes are not all trivial. So revert most of it for now. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19powerpc/64s/hash: provide arch_setup_exec hooks for hash slice setupNicholas Piggin1-0/+14
This will be used by the SLB code in the next patch, but for now this sets the slb_addr_limit to the correct size for 32-bit tasks. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-09-19powerpc/64s/hash: remove user SLB data from the pacaNicholas Piggin1-20/+9
User SLB mappig data is copied into the PACA from the mm->context so it can be accessed by the SLB miss handlers. After the C conversion, SLB miss handlers now run with relocation on, and user SLB misses are able to take recursive kernel SLB misses, so the user SLB mapping data can be removed from the paca and accessed directly. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-04-11powerpc/8xx: Fix build with hugetlbfs enabledAneesh Kumar K.V1-0/+1
8xx uses the slice code when hugetlbfs is enabled. We missed a header include on 8xx which resulted in the below build failure: config: mpc885_ads_defconfig + CONFIG_HUGETLBFS arch/powerpc/mm/slice.c: In function 'slice_get_unmapped_area': arch/powerpc/mm/slice.c:655:2: error: implicit declaration of function 'need_extra_context' arch/powerpc/mm/slice.c:656:3: error: implicit declaration of function 'alloc_extended_context' on PPC64 the mmu_context.h was included via linux/pkeys.h Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31powerpc/mm: Add support for handling > 512TB address in SLB missAneesh Kumar K.V1-1/+14
For addresses above 512TB we allocate additional mmu contexts. To make it all easy, addresses above 512TB are handled with IR/DR=1 and with stack frame setup. The mmu_context_t is also updated to track the new extended_ids. To support upto 4PB we need a total 8 contexts. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> [mpe: Minor formatting tweaks and comment wording, switch BUG to WARN in get_ea_context().] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-31powerpc/mm/slice: Consolidate return path in slice_get_unmapped_area()Aneesh Kumar K.V1-16/+20
In a following patch, on finding a free area we will need to do allocatinon of extra contexts as needed. Consolidating the return path for slice_get_unmapped_area() will make that easier. Split into a separate patch to make review easy. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13powerpc/mm/slice: remove radix calls to the slice codeNicholas Piggin1-13/+4
This is a tidy up which removes radix MMU calls into the slice code. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13powerpc/mm/slice: Use const pointers to cached slice masks where possibleNicholas Piggin1-41/+38
The slice_mask cache was a basic conversion which copied the slice mask into caller's structures, because that's how the original code worked. In most cases the pointer can be used directly instead, saving a copy and an on-stack structure. On POWER8, this increases vfork+exec+exit performance by 0.3% and reduces time to mmap+munmap a 64kB page by 2%. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13powerpc/mm/slice: remove dead codeNicholas Piggin1-6/+0
This code is never compiled in, and it gets broken by the next patch, so remove it. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13powerpc/mm/slice: Switch to 3-operand slice bitops helpersNicholas Piggin1-15/+23
This converts the slice_mask bit operation helpers to be the usual 3-operand kind, which allows 2 inputs to set a different output without an extra copy, which is used in the next patch. Adds slice_copy_mask, which will be used in the next patch. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13powerpc/mm/slice: implement slice_check_range_fitsNicholas Piggin1-28/+34
Rather than build slice masks from a range then use that to check for fit in a candidate mask, implement slice_check_range_fits that checks if a range fits in a mask directly. This allows several structures to be removed from stacks, and also we don't expect a huge range in a lot of these cases, so building and comparing a full mask is going to be more expensive than testing just one or two bits of the range. On POWER8, this increases vfork+exec+exit performance by 0.3% and reduces time to mmap+munmap a 64kB page by 5%. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13powerpc/mm/slice: implement a slice mask cacheNicholas Piggin1-42/+70
Calculating the slice mask can become a signifcant overhead for get_unmapped_area. This patch adds a struct slice_mask for each page size in the mm_context, and keeps these in synch with the slices psize arrays and slb_addr_limit. On Book3S/64 this adds 288 bytes to the mm_context_t for the slice mask caches. On POWER8, this increases vfork+exec+exit performance by 9.9% and reduces time to mmap+munmap a 64kB page by 28%. Reduces time to mmap+munmap by about 10% on 8xx. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13powerpc/mm/slice: pass pointers to struct slice_mask where possibleNicholas Piggin1-39/+45
Pass around const pointers to struct slice_mask where possible, rather than copies of slice_mask, to reduce stack and call overhead. checkstack.pl gives, before: 0x00000d1c slice_get_unmapped_area [slice.o]: 592 0x00001864 is_hugepage_only_range [slice.o]: 448 0x00000754 slice_find_area_topdown [slice.o]: 400 0x00000484 slice_find_area_bottomup.isra.1 [slice.o]: 272 0x000017b4 slice_set_range_psize [slice.o]: 224 0x00000a4c slice_find_area [slice.o]: 128 0x00000160 slice_check_fit [slice.o]: 112 after: 0x00000ad0 slice_get_unmapped_area [slice.o]: 448 0x00001464 is_hugepage_only_range [slice.o]: 288 0x000006c0 slice_find_area [slice.o]: 144 0x0000016c slice_check_fit [slice.o]: 128 0x00000528 slice_find_area_bottomup.isra.2 [slice.o]: 128 0x000013e4 slice_set_range_psize [slice.o]: 128 This increases vfork+exec+exit performance by 1.5%. Reduces time to mmap+munmap a 64kB page by 17%. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13powerpc/mm/slice: tidy lpsizes and hpsizes update loopsNicholas Piggin1-10/+12
Make these loops look the same, and change their form so the important part is not wrapped over so many lines. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-13powerpc/mm/slice: Simplify and optimise slice context initialisationNicholas Piggin1-54/+18
The slice state of an mm gets zeroed then initialised upon exec. This is the only caller of slice_set_user_psize now, so that can be removed and instead implement a faster and simplified approach that requires no locking or checking existing state. This speeds up vfork+exec+exit performance on POWER8 by 3%. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-06powerpc/mm/slice: Allow up to 64 low slicesChristophe Leroy1-27/+30
While the implementation of the "slices" address space allows a significant amount of high slices, it limits the number of low slices to 16 due to the use of a single u64 low_slices_psize element in struct mm_context_t On the 8xx, the minimum slice size is the size of the area covered by a single PMD entry, ie 4M in 4K pages mode and 64M in 16K pages mode. This means we could have at least 64 slices. In order to override this limitation, this patch switches the handling of low_slices_psize to char array as done already for high_slices_psize. 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: Michael Ellerman <mpe@ellerman.id.au>
2018-03-06powerpc/mm/slice: Enhance for supporting PPC32Christophe Leroy1-8/+29
In preparation for the following patch which will fix an issue on the 8xx by re-using the 'slices', this patch enhances the 'slices' implementation to support 32 bits CPUs. On PPC32, the address space is limited to 4Gbytes, hence only the low slices will be used. The high slices use bitmaps. As bitmap functions are not prepared to handle bitmaps of size 0, this patch ensures that bitmap functions are called only when SLICE_NUM_HIGH is not nul. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-06powerpc/mm/slice: Remove intermediate bitmap copyChristophe Leroy1-8/+4
bitmap_or() and bitmap_andnot() can work properly with dst identical to src1 or src2. There is no need of an intermediate result bitmap that is copied back to dst in a second step. Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-20powerpc/64s/slice: Use addr limit when computing slice maskAneesh Kumar K.V1-12/+22
While computing slice mask for the free area we need make sure we only search in the addr limit applicable for this mmap. We update the slb_addr_limit after we request for a mmap above 128TB. But the following mmap request with hint addr below 128TB should still limit its search to below 128TB. ie. we should not use slb_addr_limit to compute slice mask in this case. Instead, we should derive high addr limit based on the mmap hint addr value. Fixes: f4ea6dcb08ea ("powerpc/mm: Enable mappings above 128TB") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-13powerpc/64s: mm_context.addr_limit is only used on hashNicholas Piggin1-11/+11
Radix keeps no meaningful state in addr_limit, so remove it from radix code and rename to slb_addr_limit to make it clear it applies to hash only. Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-13powerpc/64s/hash: Allow MAP_FIXED allocations to cross 128TB boundaryNicholas Piggin1-1/+1
While mapping hints with a length that cross 128TB are disallowed, MAP_FIXED allocations that cross 128TB are allowed. These are failing on hash (on radix they succeed). Add an additional case for fixed mappings to expand the addr_limit when crossing 128TB. Fixes: f4ea6dcb08ea ("powerpc/mm: Enable mappings above 128TB") Cc: stable@vger.kernel.org # v4.12+ Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-13powerpc/64s/hash: Fix 128TB-512TB virtual address boundary case allocationNicholas Piggin1-26/+24
When allocating VA space with a hint that crosses 128TB, the SLB addr_limit variable is not expanded if addr is not > 128TB, but the slice allocation looks at task_size, which is 512TB. This results in slice_check_fit() incorrectly succeeding because the slice_count truncates off bit 128 of the requested mask, so the comparison to the available mask succeeds. Fix this by using mm->context.addr_limit instead of mm->task_size for testing allocation limits. This causes such allocations to fail. Fixes: f4ea6dcb08ea ("powerpc/mm: Enable mappings above 128TB") Cc: stable@vger.kernel.org # v4.12+ Reported-by: Florian Weimer <fweimer@redhat.com> Signed-off-by: Nicholas Piggin <npiggin@gmail.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-11-13powerpc/64s/hash: Fix 512T hint detection to use >= 128TMichael Ellerman1-2/+2
Currently userspace is able to request mmap() search between 128T-512T by specifying a hint address that is greater than 128T. But that means a hint of 128T exactly will return an address below 128T, which is confusing and wrong. So fix the logic to check the hint is greater than *or equal* to 128T. Fixes: f4ea6dcb08ea ("powerpc/mm: Enable mappings above 128TB") Cc: stable@vger.kernel.org # v4.12+ Suggested-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Suggested-by: Nicholas Piggin <npiggin@gmail.com> [mpe: Split out of Nick's bigger patch] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-06-19mm: larger stack guard gap, between vmasHugh Dickins1-1/+1
Stack guard page is a useful feature to reduce a risk of stack smashing into a different mapping. We have been using a single page gap which is sufficient to prevent having stack adjacent to a different mapping. But this seems to be insufficient in the light of the stack usage in userspace. E.g. glibc uses as large as 64kB alloca() in many commonly used functions. Others use constructs liks gid_t buffer[NGROUPS_MAX] which is 256kB or stack strings with MAX_ARG_STRLEN. This will become especially dangerous for suid binaries and the default no limit for the stack size limit because those applications can be tricked to consume a large portion of the stack and a single glibc call could jump over the guard page. These attacks are not theoretical, unfortunatelly. Make those attacks less probable by increasing the stack guard gap to 1MB (on systems with 4k pages; but make it depend on the page size because systems with larger base pages might cap stack allocations in the PAGE_SIZE units) which should cover larger alloca() and VLA stack allocations. It is obviously not a full fix because the problem is somehow inherent, but it should reduce attack space a lot. One could argue that the gap size should be configurable from userspace, but that can be done later when somebody finds that the new 1MB is wrong for some special case applications. For now, add a kernel command line option (stack_guard_gap) to specify the stack gap size (in page units). Implementation wise, first delete all the old code for stack guard page: because although we could get away with accounting one extra page in a stack vma, accounting a larger gap can break userspace - case in point, a program run with "ulimit -S -v 20000" failed when the 1MB gap was counted for RLIMIT_AS; similar problems could come with RLIMIT_MLOCK and strict non-overcommit mode. Instead of keeping gap inside the stack vma, maintain the stack guard gap as a gap between vmas: using vm_start_gap() in place of vm_start (or vm_end_gap() in place of vm_end if VM_GROWSUP) in just those few places which need to respect the gap - mainly arch_get_unmapped_area(), and and the vma tree's subtree_gap support for that. Original-patch-by: Oleg Nesterov <oleg@redhat.com> Original-patch-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Hugh Dickins <hughd@google.com> Acked-by: Michal Hocko <mhocko@suse.com> Tested-by: Helge Deller <deller@gmx.de> # parisc Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-04-19powerpc/mmap: Any hint > 128TB searches the full VA spaceAneesh Kumar K.V1-1/+2
As part of the new large address space support, processes start out life with a 128TB virtual address space. However when calling mmap() a process can pass a hint address, and if that hint is > 128TB the kernel will use the full 512TB address space to try and satisfy the mmap() request. Currently we have a check that the hint is > 128TB and < 512TB (TASK_SIZE), which was added as an optimisation to avoid updating addr_limit unnecessarily and also to avoid calling slice_flush_segments() on all CPUs more than necessary. However this has the user-visible side effect that an mmap() hint above 512TB does not search the full address space unless a preceding mmap() used a hint value > 128TB && < 512TB. So fix it to treat any hint above 128TB as a hint to search the full address space, instead of checking the hint against TASK_SIZE, we instead check if the addr_limit is already == TASK_SIZE. This also brings the ABI in-line with what is proposed on x86. ie, that a hint address above 128TB up to and including (2^64)-1 is an indication to search the full address space. Fixes: f4ea6dcb08ea2c (powerpc/mm: Enable mappings above 128TB) Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-19powerpc/mm/radix: Use mm->task_size for boundary checking instead of addr_limitAneesh Kumar K.V1-2/+2
We don't init addr_limit correctly for 32 bit applications. So default to using mm->task_size for boundary condition checking. We use addr_limit to only control free space search. This makes sure that we do the right thing with 32 bit applications. We should consolidate the usage of TASK_SIZE/mm->task_size and mm->context.addr_limit later. This partially reverts commit fbfef9027c2a7ad (powerpc/mm: Switch some TASK_SIZE checks to use mm_context addr_limit). Fixes: fbfef9027c2a ("powerpc/mm: Switch some TASK_SIZE checks to use mm_context addr_limit") Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-01powerpc/mm: Enable mappings above 128TBAneesh Kumar K.V1-12/+42
Not all user space application is ready to handle wide addresses. It's known that at least some JIT compilers use higher bits in pointers to encode their information. It collides with valid pointers with 512TB addresses and leads to crashes. To mitigate this, we are not going to allocate virtual address space above 128TB by default. But userspace can ask for allocation from full address space by specifying hint address (with or without MAP_FIXED) above 128TB. If hint address set above 128TB, but MAP_FIXED is not specified, we try to look for unmapped area by specified address. If it's already occupied, we look for unmapped area in *full* address space, rather than from 128TB window. This approach helps to easily make application's memory allocator aware about large address space without manually tracking allocated virtual address space. This is going to be a per mmap decision. ie, we can have some mmaps with larger addresses and other that do not. A sample memory layout looks like: 10000000-10010000 r-xp 00000000 fc:00 9057045 /home/max_addr_512TB 10010000-10020000 r--p 00000000 fc:00 9057045 /home/max_addr_512TB 10020000-10030000 rw-p 00010000 fc:00 9057045 /home/max_addr_512TB 10029630000-10029660000 rw-p 00000000 00:00 0 [heap] 7fff834a0000-7fff834b0000 rw-p 00000000 00:00 0 7fff834b0000-7fff83670000 r-xp 00000000 fc:00 9177190 /lib/powerpc64le-linux-gnu/libc-2.23.so 7fff83670000-7fff83680000 r--p 001b0000 fc:00 9177190 /lib/powerpc64le-linux-gnu/libc-2.23.so 7fff83680000-7fff83690000 rw-p 001c0000 fc:00 9177190 /lib/powerpc64le-linux-gnu/libc-2.23.so 7fff83690000-7fff836a0000 rw-p 00000000 00:00 0 7fff836a0000-7fff836c0000 r-xp 00000000 00:00 0 [vdso] 7fff836c0000-7fff83700000 r-xp 00000000 fc:00 9177193 /lib/powerpc64le-linux-gnu/ld-2.23.so 7fff83700000-7fff83710000 r--p 00030000 fc:00 9177193 /lib/powerpc64le-linux-gnu/ld-2.23.so 7fff83710000-7fff83720000 rw-p 00040000 fc:00 9177193 /lib/powerpc64le-linux-gnu/ld-2.23.so 7fffdccf0000-7fffdcd20000 rw-p 00000000 00:00 0 [stack] 1000000000000-1000000010000 rw-p 00000000 00:00 0 1ffff83710000-1ffff83720000 rw-p 00000000 00:00 0 Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-01powerpc/mm: Switch some TASK_SIZE checks to use mm_context addr_limitAneesh Kumar K.V1-3/+3
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-04-01powerpc/mm: Add addr_limit to mm_context and use it to derive max slice indexAneesh Kumar K.V1-9/+11
In the followup patch, we will increase the slice array size to handle 512TB range, but will limit the max addr to 128TB. Avoid doing unnecessary computation and avoid doing slice mask related operation above address limit. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-31powerpc/mm/slice: Update slice mask printing to use bitmap printing.Aneesh Kumar K.V1-23/+7
We now get output like below which is much better. [ 0.935306] good_mask low_slice: 0-15 [ 0.935360] good_mask high_slice: 0-511 Compared to [ 0.953414] good_mask:1111111111111111 - 1111111111111......... I also fixed an error with slice_dbg printing. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-31powerpc/mm/slice: Move slice_mask struct definition to slice.cAneesh Kumar K.V1-1/+9
This structure definition need not be in a header since this is used only by slice.c file. So move it to slice.c. This also allow us to use SLICE_NUM_HIGH instead of 64. I also switch the low_slices type to u64 from u16. This doesn't have an impact on size of struct due to padding added with u16 type. This helps in using bitmap printing function for printing slice mask. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-31powerpc/mm: Move copy_mm_to_paca to paca.cAneesh Kumar K.V1-1/+1
We also update the function arg to struct mm_struct. Move this so that function finds the definition of struct mm_struct. No functional change in this patch. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-31powerpc/mm/slice: Update the function prototypeAneesh Kumar K.V1-34/+28
This avoid copying the slice_mask struct as function return value Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-31powerpc/mm/slice: Convert slice_mask high slice to a bitmapAneesh Kumar K.V1-37/+75
In followup patch we want to increase the va range which will result in us requiring high_slices to have more than 64 bits. To enable this convert high_slices to bitmap. We keep the number bits same in this patch and later change that to higher value Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> [mpe: Fold in fix to use bitmap_empty()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2017-03-31powerpc/mm/slice: Fix off-by-1 error when computing slice maskAneesh Kumar K.V1-3/+2
For low slice, max addr should be less than 4G. Without limiting this correctly we will end up with a low slice mask which has 17th bit set. This is not a problem with the current code because our low slice mask is of type u16. But in later patch I am switching low slice mask to u64 type and having the 17bit set result in wrong slice mask which in turn results in mmap failures. Reviewed-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-11powerpc/mm/radix: Add checks in slice code to catch radix usageAneesh Kumar K.V1-0/+16
Radix doesn't need slice support. Catch incorrect usage of slice code when radix is enabled. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-05-01powerpc/mm: Make page table size a variableAneesh Kumar K.V1-2/+2
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>
2015-12-19powerpc: Add function to copy mm_context_t to the pacaMichael Neuling1-2/+1
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>