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OpenCloudOS-Kernel/arch/s390/mm/pgtable.c

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[S390] Cleanup page table definitions. - De-confuse the defines for the address-space-control-elements and the segment/region table entries. - Create out of line functions for page table allocation / freeing. - Simplify get_shadow_xxx functions. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-10-22 18:52:47 +08:00
/*
s390/comments: unify copyright messages and remove file names Remove the file name from the comment at top of many files. In most cases the file name was wrong anyway, so it's rather pointless. Also unify the IBM copyright statement. We did have a lot of sightly different statements and wanted to change them one after another whenever a file gets touched. However that never happened. Instead people start to take the old/"wrong" statements to use as a template for new files. So unify all of them in one go. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2012-07-20 17:15:04 +08:00
* Copyright IBM Corp. 2007, 2011
[S390] Cleanup page table definitions. - De-confuse the defines for the address-space-control-elements and the segment/region table entries. - Create out of line functions for page table allocation / freeing. - Simplify get_shadow_xxx functions. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-10-22 18:52:47 +08:00
* Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
*/
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/gfp.h>
[S390] Cleanup page table definitions. - De-confuse the defines for the address-space-control-elements and the segment/region table entries. - Create out of line functions for page table allocation / freeing. - Simplify get_shadow_xxx functions. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-10-22 18:52:47 +08:00
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/smp.h>
#include <linux/spinlock.h>
[S390] lockless get_user_pages_fast() Implement get_user_pages_fast without locking in the fastpath on s390. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2010-10-25 22:10:11 +08:00
#include <linux/rcupdate.h>
[S390] kvm guest address space mapping Add code that allows KVM to control the virtual memory layout that is seen by a guest. The guest address space uses a second page table that shares the last level pte-tables with the process page table. If a page is unmapped from the process page table it is automatically unmapped from the guest page table as well. The guest address space mapping starts out empty, KVM can map any individual 1MB segments from the process virtual memory to any 1MB aligned location in the guest virtual memory. If a target segment in the process virtual memory does not exist or is unmapped while a guest mapping exists the desired target address is stored as an invalid segment table entry in the guest page table. The population of the guest page table is fault driven. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2011-07-24 16:48:20 +08:00
#include <linux/slab.h>
s390/kvm: support collaborative memory management This patch enables Collaborative Memory Management (CMM) for kvm on s390. CMM allows the guest to inform the host about page usage (see arch/s390/mm/cmm.c). The host uses this information to avoid swapping in unused pages in the page fault handler. Further, a CPU provided list of unused invalid pages is processed to reclaim swap space of not yet accessed unused pages. [ Martin Schwidefsky: patch reordering and cleanup ] Signed-off-by: Konstantin Weitz <konstantin.weitz@gmail.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-04-17 23:36:29 +08:00
#include <linux/swapops.h>
s390/kvm: remove delayed reallocation of page tables for KVM Replacing a 2K page table with a 4K page table while a VMA is active for the affected memory region is fundamentally broken. Rip out the page table reallocation code and replace it with a simple system control 'vm.allocate_pgste'. If the system control is set the page tables for all processes are allocated as full 4K pages, even for processes that do not need it. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2015-04-15 19:23:26 +08:00
#include <linux/sysctl.h>
s390/mm: disable KSM for storage key enabled pages When storage keys are enabled unmerge already merged pages and prevent new pages from being merged. Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com> Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-10-23 18:09:17 +08:00
#include <linux/ksm.h>
#include <linux/mman.h>
[S390] Cleanup page table definitions. - De-confuse the defines for the address-space-control-elements and the segment/region table entries. - Create out of line functions for page table allocation / freeing. - Simplify get_shadow_xxx functions. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-10-22 18:52:47 +08:00
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
#include <asm/tlb.h>
#include <asm/tlbflush.h>
[S390] dynamic page tables. Add support for different number of page table levels dependent on the highest address used for a process. This will cause a 31 bit process to use a two level page table instead of the four level page table that is the default after the pud has been introduced. Likewise a normal 64 bit process will use three levels instead of four. Only if a process runs out of the 4 tera bytes which can be addressed with a three level page table the fourth level is dynamically added. Then the process can use up to 8 peta byte. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-02-10 01:24:37 +08:00
#include <asm/mmu_context.h>
[S390] Cleanup page table definitions. - De-confuse the defines for the address-space-control-elements and the segment/region table entries. - Create out of line functions for page table allocation / freeing. - Simplify get_shadow_xxx functions. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2007-10-22 18:52:47 +08:00
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
static inline pte_t ptep_flush_direct(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
pte_t old;
old = *ptep;
if (unlikely(pte_val(old) & _PAGE_INVALID))
return old;
s390/mm: simplify the TLB flushing code ptep_flush_lazy and pmdp_flush_lazy use mm->context.attach_count to decide between a lazy TLB flush vs an immediate TLB flush. The field contains two 16-bit counters, the number of CPUs that have the mm attached and can create TLB entries for it and the number of CPUs in the middle of a page table update. The __tlb_flush_asce, ptep_flush_direct and pmdp_flush_direct functions use the attach counter and a mask check with mm_cpumask(mm) to decide between a local flush local of the current CPU and a global flush. For all these functions the decision between lazy vs immediate and local vs global TLB flush can be based on CPU masks. There are two masks: the mm->context.cpu_attach_mask with the CPUs that are actively using the mm, and the mm_cpumask(mm) with the CPUs that have used the mm since the last full flush. The decision between lazy vs immediate flush is based on the mm->context.cpu_attach_mask, to decide between local vs global flush the mm_cpumask(mm) is used. With this patch all checks will use the CPU masks, the old counter mm->context.attach_count with its two 16-bit values is turned into a single counter mm->context.flush_count that keeps track of the number of CPUs with incomplete page table updates. The sole user of this counter is finish_arch_post_lock_switch() which waits for the end of all page table updates. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-05-25 15:45:26 +08:00
atomic_inc(&mm->context.flush_count);
if (MACHINE_HAS_TLB_LC &&
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
s390/mm: merge local / non-local IPTE helper 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>
2016-06-14 18:38:40 +08:00
__ptep_ipte(addr, ptep, IPTE_LOCAL);
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
else
s390/mm: merge local / non-local IPTE helper 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>
2016-06-14 18:38:40 +08:00
__ptep_ipte(addr, ptep, IPTE_GLOBAL);
s390/mm: simplify the TLB flushing code ptep_flush_lazy and pmdp_flush_lazy use mm->context.attach_count to decide between a lazy TLB flush vs an immediate TLB flush. The field contains two 16-bit counters, the number of CPUs that have the mm attached and can create TLB entries for it and the number of CPUs in the middle of a page table update. The __tlb_flush_asce, ptep_flush_direct and pmdp_flush_direct functions use the attach counter and a mask check with mm_cpumask(mm) to decide between a local flush local of the current CPU and a global flush. For all these functions the decision between lazy vs immediate and local vs global TLB flush can be based on CPU masks. There are two masks: the mm->context.cpu_attach_mask with the CPUs that are actively using the mm, and the mm_cpumask(mm) with the CPUs that have used the mm since the last full flush. The decision between lazy vs immediate flush is based on the mm->context.cpu_attach_mask, to decide between local vs global flush the mm_cpumask(mm) is used. With this patch all checks will use the CPU masks, the old counter mm->context.attach_count with its two 16-bit values is turned into a single counter mm->context.flush_count that keeps track of the number of CPUs with incomplete page table updates. The sole user of this counter is finish_arch_post_lock_switch() which waits for the end of all page table updates. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-05-25 15:45:26 +08:00
atomic_dec(&mm->context.flush_count);
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
return old;
}
static inline pte_t ptep_flush_lazy(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
pte_t old;
old = *ptep;
if (unlikely(pte_val(old) & _PAGE_INVALID))
return old;
s390/mm: simplify the TLB flushing code ptep_flush_lazy and pmdp_flush_lazy use mm->context.attach_count to decide between a lazy TLB flush vs an immediate TLB flush. The field contains two 16-bit counters, the number of CPUs that have the mm attached and can create TLB entries for it and the number of CPUs in the middle of a page table update. The __tlb_flush_asce, ptep_flush_direct and pmdp_flush_direct functions use the attach counter and a mask check with mm_cpumask(mm) to decide between a local flush local of the current CPU and a global flush. For all these functions the decision between lazy vs immediate and local vs global TLB flush can be based on CPU masks. There are two masks: the mm->context.cpu_attach_mask with the CPUs that are actively using the mm, and the mm_cpumask(mm) with the CPUs that have used the mm since the last full flush. The decision between lazy vs immediate flush is based on the mm->context.cpu_attach_mask, to decide between local vs global flush the mm_cpumask(mm) is used. With this patch all checks will use the CPU masks, the old counter mm->context.attach_count with its two 16-bit values is turned into a single counter mm->context.flush_count that keeps track of the number of CPUs with incomplete page table updates. The sole user of this counter is finish_arch_post_lock_switch() which waits for the end of all page table updates. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-05-25 15:45:26 +08:00
atomic_inc(&mm->context.flush_count);
if (cpumask_equal(&mm->context.cpu_attach_mask,
cpumask_of(smp_processor_id()))) {
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
pte_val(*ptep) |= _PAGE_INVALID;
mm->context.flush_mm = 1;
} else
s390/mm: merge local / non-local IPTE helper 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>
2016-06-14 18:38:40 +08:00
__ptep_ipte(addr, ptep, IPTE_GLOBAL);
s390/mm: simplify the TLB flushing code ptep_flush_lazy and pmdp_flush_lazy use mm->context.attach_count to decide between a lazy TLB flush vs an immediate TLB flush. The field contains two 16-bit counters, the number of CPUs that have the mm attached and can create TLB entries for it and the number of CPUs in the middle of a page table update. The __tlb_flush_asce, ptep_flush_direct and pmdp_flush_direct functions use the attach counter and a mask check with mm_cpumask(mm) to decide between a local flush local of the current CPU and a global flush. For all these functions the decision between lazy vs immediate and local vs global TLB flush can be based on CPU masks. There are two masks: the mm->context.cpu_attach_mask with the CPUs that are actively using the mm, and the mm_cpumask(mm) with the CPUs that have used the mm since the last full flush. The decision between lazy vs immediate flush is based on the mm->context.cpu_attach_mask, to decide between local vs global flush the mm_cpumask(mm) is used. With this patch all checks will use the CPU masks, the old counter mm->context.attach_count with its two 16-bit values is turned into a single counter mm->context.flush_count that keeps track of the number of CPUs with incomplete page table updates. The sole user of this counter is finish_arch_post_lock_switch() which waits for the end of all page table updates. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-05-25 15:45:26 +08:00
atomic_dec(&mm->context.flush_count);
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
return old;
}
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
static inline pgste_t pgste_get_lock(pte_t *ptep)
{
unsigned long new = 0;
#ifdef CONFIG_PGSTE
unsigned long old;
asm(
" lg %0,%2\n"
"0: lgr %1,%0\n"
" nihh %0,0xff7f\n" /* clear PCL bit in old */
" oihh %1,0x0080\n" /* set PCL bit in new */
" csg %0,%1,%2\n"
" jl 0b\n"
: "=&d" (old), "=&d" (new), "=Q" (ptep[PTRS_PER_PTE])
: "Q" (ptep[PTRS_PER_PTE]) : "cc", "memory");
#endif
return __pgste(new);
}
static inline void pgste_set_unlock(pte_t *ptep, pgste_t pgste)
{
#ifdef CONFIG_PGSTE
asm(
" nihh %1,0xff7f\n" /* clear PCL bit */
" stg %1,%0\n"
: "=Q" (ptep[PTRS_PER_PTE])
: "d" (pgste_val(pgste)), "Q" (ptep[PTRS_PER_PTE])
: "cc", "memory");
#endif
}
static inline pgste_t pgste_get(pte_t *ptep)
{
unsigned long pgste = 0;
#ifdef CONFIG_PGSTE
pgste = *(unsigned long *)(ptep + PTRS_PER_PTE);
#endif
return __pgste(pgste);
}
static inline void pgste_set(pte_t *ptep, pgste_t pgste)
{
#ifdef CONFIG_PGSTE
*(pgste_t *)(ptep + PTRS_PER_PTE) = pgste;
#endif
}
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
static inline pgste_t pgste_update_all(pte_t pte, pgste_t pgste,
struct mm_struct *mm)
{
#ifdef CONFIG_PGSTE
unsigned long address, bits, skey;
if (!mm_use_skey(mm) || pte_val(pte) & _PAGE_INVALID)
return pgste;
address = pte_val(pte) & PAGE_MASK;
skey = (unsigned long) page_get_storage_key(address);
bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED);
/* Transfer page changed & referenced bit to guest bits in pgste */
pgste_val(pgste) |= bits << 48; /* GR bit & GC bit */
/* Copy page access key and fetch protection bit to pgste */
pgste_val(pgste) &= ~(PGSTE_ACC_BITS | PGSTE_FP_BIT);
pgste_val(pgste) |= (skey & (_PAGE_ACC_BITS | _PAGE_FP_BIT)) << 56;
#endif
return pgste;
}
static inline void pgste_set_key(pte_t *ptep, pgste_t pgste, pte_t entry,
struct mm_struct *mm)
{
#ifdef CONFIG_PGSTE
unsigned long address;
unsigned long nkey;
if (!mm_use_skey(mm) || pte_val(entry) & _PAGE_INVALID)
return;
VM_BUG_ON(!(pte_val(*ptep) & _PAGE_INVALID));
address = pte_val(entry) & PAGE_MASK;
/*
* Set page access key and fetch protection bit from pgste.
* The guest C/R information is still in the PGSTE, set real
* key C/R to 0.
*/
nkey = (pgste_val(pgste) & (PGSTE_ACC_BITS | PGSTE_FP_BIT)) >> 56;
nkey |= (pgste_val(pgste) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 48;
page_set_storage_key(address, nkey, 0);
#endif
}
static inline pgste_t pgste_set_pte(pte_t *ptep, pgste_t pgste, pte_t entry)
{
#ifdef CONFIG_PGSTE
if ((pte_val(entry) & _PAGE_PRESENT) &&
(pte_val(entry) & _PAGE_WRITE) &&
!(pte_val(entry) & _PAGE_INVALID)) {
if (!MACHINE_HAS_ESOP) {
/*
* Without enhanced suppression-on-protection force
* the dirty bit on for all writable ptes.
*/
pte_val(entry) |= _PAGE_DIRTY;
pte_val(entry) &= ~_PAGE_PROTECT;
}
if (!(pte_val(entry) & _PAGE_PROTECT))
/* This pte allows write access, set user-dirty */
pgste_val(pgste) |= PGSTE_UC_BIT;
}
#endif
*ptep = entry;
return pgste;
}
s390/mm: extended gmap pte notifier The current gmap pte notifier forces a pte into to a read-write state. If the pte is invalidated the gmap notifier is called to inform KVM that the mapping will go away. Extend this approach to allow read-write, read-only and no-access as possible target states and call the pte notifier for any change to the pte. This mechanism is used to temporarily set specific access rights for a pte without doing the heavy work of a true mprotect call. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 18:54:42 +08:00
static inline pgste_t pgste_pte_notify(struct mm_struct *mm,
unsigned long addr,
pte_t *ptep, pgste_t pgste)
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
{
#ifdef CONFIG_PGSTE
s390/mm: add shadow gmap support For a nested KVM guest the outer KVM host needs to create shadow page tables for the nested guest. This patch adds the basic support to the guest address space (gmap) code. For each guest address space the inner KVM host creates, the first outer KVM host needs to create shadow page tables. The address space is identified by the ASCE loaded into the control register 1 at the time the inner SIE instruction for the second nested KVM guest is executed. The outer KVM host creates the shadow tables starting with the table identified by the ASCE on a on-demand basis. The outer KVM host will get repeated faults for all the shadow tables needed to run the second KVM guest. While a shadow page table for the second KVM guest is active the access to the origin region, segment and page tables needs to be restricted for the first KVM guest. For region and segment and page tables the first KVM guest may read the memory, but write attempt has to lead to an unshadow. This is done using the page invalid and read-only bits in the page table of the first KVM guest. If the first guest re-accesses one of the origin pages of a shadow, it gets a fault and the affected parts of the shadow page table hierarchy needs to be removed again. PGSTE tables don't have to be shadowed, as all interpretation assist can't deal with the invalid bits in the shadow pte being set differently than the original ones provided by the first KVM guest. Many bug fixes and improvements by David Hildenbrand. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:12:18 +08:00
unsigned long bits;
bits = pgste_val(pgste) & (PGSTE_IN_BIT | PGSTE_VSIE_BIT);
if (bits) {
pgste_val(pgste) ^= bits;
ptep_notify(mm, addr, ptep, bits);
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
}
#endif
return pgste;
}
static inline pgste_t ptep_xchg_start(struct mm_struct *mm,
unsigned long addr, pte_t *ptep)
{
pgste_t pgste = __pgste(0);
if (mm_has_pgste(mm)) {
pgste = pgste_get_lock(ptep);
s390/mm: extended gmap pte notifier The current gmap pte notifier forces a pte into to a read-write state. If the pte is invalidated the gmap notifier is called to inform KVM that the mapping will go away. Extend this approach to allow read-write, read-only and no-access as possible target states and call the pte notifier for any change to the pte. This mechanism is used to temporarily set specific access rights for a pte without doing the heavy work of a true mprotect call. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 18:54:42 +08:00
pgste = pgste_pte_notify(mm, addr, ptep, pgste);
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
}
return pgste;
}
static inline void ptep_xchg_commit(struct mm_struct *mm,
unsigned long addr, pte_t *ptep,
pgste_t pgste, pte_t old, pte_t new)
{
if (mm_has_pgste(mm)) {
if (pte_val(old) & _PAGE_INVALID)
pgste_set_key(ptep, pgste, new, mm);
if (pte_val(new) & _PAGE_INVALID) {
pgste = pgste_update_all(old, pgste, mm);
if ((pgste_val(pgste) & _PGSTE_GPS_USAGE_MASK) ==
_PGSTE_GPS_USAGE_UNUSED)
pte_val(old) |= _PAGE_UNUSED;
}
pgste = pgste_set_pte(ptep, pgste, new);
pgste_set_unlock(ptep, pgste);
} else {
*ptep = new;
}
}
pte_t ptep_xchg_direct(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t new)
{
pgste_t pgste;
pte_t old;
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_disable();
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
pgste = ptep_xchg_start(mm, addr, ptep);
old = ptep_flush_direct(mm, addr, ptep);
ptep_xchg_commit(mm, addr, ptep, pgste, old, new);
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_enable();
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
return old;
}
EXPORT_SYMBOL(ptep_xchg_direct);
pte_t ptep_xchg_lazy(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t new)
{
pgste_t pgste;
pte_t old;
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_disable();
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
pgste = ptep_xchg_start(mm, addr, ptep);
old = ptep_flush_lazy(mm, addr, ptep);
ptep_xchg_commit(mm, addr, ptep, pgste, old, new);
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_enable();
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
return old;
}
EXPORT_SYMBOL(ptep_xchg_lazy);
pte_t ptep_modify_prot_start(struct mm_struct *mm, unsigned long addr,
pte_t *ptep)
{
pgste_t pgste;
pte_t old;
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_disable();
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
pgste = ptep_xchg_start(mm, addr, ptep);
old = ptep_flush_lazy(mm, addr, ptep);
if (mm_has_pgste(mm)) {
pgste = pgste_update_all(old, pgste, mm);
pgste_set(ptep, pgste);
}
return old;
}
EXPORT_SYMBOL(ptep_modify_prot_start);
void ptep_modify_prot_commit(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t pte)
{
pgste_t pgste;
s390: add no-execute support 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>
2016-03-22 17:54:24 +08:00
if (!MACHINE_HAS_NX)
pte_val(pte) &= ~_PAGE_NOEXEC;
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
if (mm_has_pgste(mm)) {
pgste = pgste_get(ptep);
pgste_set_key(ptep, pgste, pte, mm);
pgste = pgste_set_pte(ptep, pgste, pte);
pgste_set_unlock(ptep, pgste);
} else {
*ptep = pte;
}
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_enable();
s390/mm: uninline ptep_xxx functions from pgtable.h The code in the various ptep_xxx functions has grown quite large, consolidate them to four out-of-line functions: ptep_xchg_direct to exchange a pte with another with immediate flushing ptep_xchg_lazy to exchange a pte with another in a batched update ptep_modify_prot_start to begin a protection flags update ptep_modify_prot_commit to commit a protection flags update Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:08:09 +08:00
}
EXPORT_SYMBOL(ptep_modify_prot_commit);
s390/mm: uninline pmdp_xxx functions from pgtable.h The pmdp_xxx function are smaller than their ptep_xxx counterparts but to keep things symmetrical unline them as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:09:25 +08:00
static inline pmd_t pmdp_flush_direct(struct mm_struct *mm,
unsigned long addr, pmd_t *pmdp)
{
pmd_t old;
old = *pmdp;
if (pmd_val(old) & _SEGMENT_ENTRY_INVALID)
return old;
if (!MACHINE_HAS_IDTE) {
__pmdp_csp(pmdp);
return old;
}
s390/mm: simplify the TLB flushing code ptep_flush_lazy and pmdp_flush_lazy use mm->context.attach_count to decide between a lazy TLB flush vs an immediate TLB flush. The field contains two 16-bit counters, the number of CPUs that have the mm attached and can create TLB entries for it and the number of CPUs in the middle of a page table update. The __tlb_flush_asce, ptep_flush_direct and pmdp_flush_direct functions use the attach counter and a mask check with mm_cpumask(mm) to decide between a local flush local of the current CPU and a global flush. For all these functions the decision between lazy vs immediate and local vs global TLB flush can be based on CPU masks. There are two masks: the mm->context.cpu_attach_mask with the CPUs that are actively using the mm, and the mm_cpumask(mm) with the CPUs that have used the mm since the last full flush. The decision between lazy vs immediate flush is based on the mm->context.cpu_attach_mask, to decide between local vs global flush the mm_cpumask(mm) is used. With this patch all checks will use the CPU masks, the old counter mm->context.attach_count with its two 16-bit values is turned into a single counter mm->context.flush_count that keeps track of the number of CPUs with incomplete page table updates. The sole user of this counter is finish_arch_post_lock_switch() which waits for the end of all page table updates. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-05-25 15:45:26 +08:00
atomic_inc(&mm->context.flush_count);
if (MACHINE_HAS_TLB_LC &&
s390/mm: uninline pmdp_xxx functions from pgtable.h The pmdp_xxx function are smaller than their ptep_xxx counterparts but to keep things symmetrical unline them as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:09:25 +08:00
cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
s390/mm: merge local / non-local IDTE helper Merge the __p[m|u]xdp_idte and __p[m|u]dp_idte_local functions into a single __p[m|u]dp_idte function with an additional parameter. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-14 18:41:35 +08:00
__pmdp_idte(addr, pmdp, IDTE_LOCAL);
s390/mm: uninline pmdp_xxx functions from pgtable.h The pmdp_xxx function are smaller than their ptep_xxx counterparts but to keep things symmetrical unline them as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:09:25 +08:00
else
s390/mm: merge local / non-local IDTE helper Merge the __p[m|u]xdp_idte and __p[m|u]dp_idte_local functions into a single __p[m|u]dp_idte function with an additional parameter. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-14 18:41:35 +08:00
__pmdp_idte(addr, pmdp, IDTE_GLOBAL);
s390/mm: simplify the TLB flushing code ptep_flush_lazy and pmdp_flush_lazy use mm->context.attach_count to decide between a lazy TLB flush vs an immediate TLB flush. The field contains two 16-bit counters, the number of CPUs that have the mm attached and can create TLB entries for it and the number of CPUs in the middle of a page table update. The __tlb_flush_asce, ptep_flush_direct and pmdp_flush_direct functions use the attach counter and a mask check with mm_cpumask(mm) to decide between a local flush local of the current CPU and a global flush. For all these functions the decision between lazy vs immediate and local vs global TLB flush can be based on CPU masks. There are two masks: the mm->context.cpu_attach_mask with the CPUs that are actively using the mm, and the mm_cpumask(mm) with the CPUs that have used the mm since the last full flush. The decision between lazy vs immediate flush is based on the mm->context.cpu_attach_mask, to decide between local vs global flush the mm_cpumask(mm) is used. With this patch all checks will use the CPU masks, the old counter mm->context.attach_count with its two 16-bit values is turned into a single counter mm->context.flush_count that keeps track of the number of CPUs with incomplete page table updates. The sole user of this counter is finish_arch_post_lock_switch() which waits for the end of all page table updates. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-05-25 15:45:26 +08:00
atomic_dec(&mm->context.flush_count);
s390/mm: uninline pmdp_xxx functions from pgtable.h The pmdp_xxx function are smaller than their ptep_xxx counterparts but to keep things symmetrical unline them as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:09:25 +08:00
return old;
}
static inline pmd_t pmdp_flush_lazy(struct mm_struct *mm,
unsigned long addr, pmd_t *pmdp)
{
pmd_t old;
old = *pmdp;
if (pmd_val(old) & _SEGMENT_ENTRY_INVALID)
return old;
s390/mm: simplify the TLB flushing code ptep_flush_lazy and pmdp_flush_lazy use mm->context.attach_count to decide between a lazy TLB flush vs an immediate TLB flush. The field contains two 16-bit counters, the number of CPUs that have the mm attached and can create TLB entries for it and the number of CPUs in the middle of a page table update. The __tlb_flush_asce, ptep_flush_direct and pmdp_flush_direct functions use the attach counter and a mask check with mm_cpumask(mm) to decide between a local flush local of the current CPU and a global flush. For all these functions the decision between lazy vs immediate and local vs global TLB flush can be based on CPU masks. There are two masks: the mm->context.cpu_attach_mask with the CPUs that are actively using the mm, and the mm_cpumask(mm) with the CPUs that have used the mm since the last full flush. The decision between lazy vs immediate flush is based on the mm->context.cpu_attach_mask, to decide between local vs global flush the mm_cpumask(mm) is used. With this patch all checks will use the CPU masks, the old counter mm->context.attach_count with its two 16-bit values is turned into a single counter mm->context.flush_count that keeps track of the number of CPUs with incomplete page table updates. The sole user of this counter is finish_arch_post_lock_switch() which waits for the end of all page table updates. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-05-25 15:45:26 +08:00
atomic_inc(&mm->context.flush_count);
if (cpumask_equal(&mm->context.cpu_attach_mask,
cpumask_of(smp_processor_id()))) {
s390/mm: uninline pmdp_xxx functions from pgtable.h The pmdp_xxx function are smaller than their ptep_xxx counterparts but to keep things symmetrical unline them as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:09:25 +08:00
pmd_val(*pmdp) |= _SEGMENT_ENTRY_INVALID;
mm->context.flush_mm = 1;
} else if (MACHINE_HAS_IDTE)
s390/mm: merge local / non-local IDTE helper Merge the __p[m|u]xdp_idte and __p[m|u]dp_idte_local functions into a single __p[m|u]dp_idte function with an additional parameter. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-14 18:41:35 +08:00
__pmdp_idte(addr, pmdp, IDTE_GLOBAL);
s390/mm: uninline pmdp_xxx functions from pgtable.h The pmdp_xxx function are smaller than their ptep_xxx counterparts but to keep things symmetrical unline them as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:09:25 +08:00
else
__pmdp_csp(pmdp);
s390/mm: simplify the TLB flushing code ptep_flush_lazy and pmdp_flush_lazy use mm->context.attach_count to decide between a lazy TLB flush vs an immediate TLB flush. The field contains two 16-bit counters, the number of CPUs that have the mm attached and can create TLB entries for it and the number of CPUs in the middle of a page table update. The __tlb_flush_asce, ptep_flush_direct and pmdp_flush_direct functions use the attach counter and a mask check with mm_cpumask(mm) to decide between a local flush local of the current CPU and a global flush. For all these functions the decision between lazy vs immediate and local vs global TLB flush can be based on CPU masks. There are two masks: the mm->context.cpu_attach_mask with the CPUs that are actively using the mm, and the mm_cpumask(mm) with the CPUs that have used the mm since the last full flush. The decision between lazy vs immediate flush is based on the mm->context.cpu_attach_mask, to decide between local vs global flush the mm_cpumask(mm) is used. With this patch all checks will use the CPU masks, the old counter mm->context.attach_count with its two 16-bit values is turned into a single counter mm->context.flush_count that keeps track of the number of CPUs with incomplete page table updates. The sole user of this counter is finish_arch_post_lock_switch() which waits for the end of all page table updates. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-05-25 15:45:26 +08:00
atomic_dec(&mm->context.flush_count);
s390/mm: uninline pmdp_xxx functions from pgtable.h The pmdp_xxx function are smaller than their ptep_xxx counterparts but to keep things symmetrical unline them as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:09:25 +08:00
return old;
}
pmd_t pmdp_xchg_direct(struct mm_struct *mm, unsigned long addr,
pmd_t *pmdp, pmd_t new)
{
pmd_t old;
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_disable();
s390/mm: uninline pmdp_xxx functions from pgtable.h The pmdp_xxx function are smaller than their ptep_xxx counterparts but to keep things symmetrical unline them as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:09:25 +08:00
old = pmdp_flush_direct(mm, addr, pmdp);
*pmdp = new;
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_enable();
s390/mm: uninline pmdp_xxx functions from pgtable.h The pmdp_xxx function are smaller than their ptep_xxx counterparts but to keep things symmetrical unline them as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:09:25 +08:00
return old;
}
EXPORT_SYMBOL(pmdp_xchg_direct);
pmd_t pmdp_xchg_lazy(struct mm_struct *mm, unsigned long addr,
pmd_t *pmdp, pmd_t new)
{
pmd_t old;
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_disable();
s390/mm: uninline pmdp_xxx functions from pgtable.h The pmdp_xxx function are smaller than their ptep_xxx counterparts but to keep things symmetrical unline them as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:09:25 +08:00
old = pmdp_flush_lazy(mm, addr, pmdp);
*pmdp = new;
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_enable();
s390/mm: uninline pmdp_xxx functions from pgtable.h The pmdp_xxx function are smaller than their ptep_xxx counterparts but to keep things symmetrical unline them as well. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:09:25 +08:00
return old;
}
EXPORT_SYMBOL(pmdp_xchg_lazy);
s390/mm: add support for 2GB hugepages This adds support for 2GB hugetlbfs pages on s390. Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-07-04 20:47:01 +08:00
static inline pud_t pudp_flush_direct(struct mm_struct *mm,
unsigned long addr, pud_t *pudp)
{
pud_t old;
old = *pudp;
if (pud_val(old) & _REGION_ENTRY_INVALID)
return old;
if (!MACHINE_HAS_IDTE) {
/*
* Invalid bit position is the same for pmd and pud, so we can
* re-use _pmd_csp() here
*/
__pmdp_csp((pmd_t *) pudp);
return old;
}
atomic_inc(&mm->context.flush_count);
if (MACHINE_HAS_TLB_LC &&
cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id())))
s390/mm: merge local / non-local IDTE helper Merge the __p[m|u]xdp_idte and __p[m|u]dp_idte_local functions into a single __p[m|u]dp_idte function with an additional parameter. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-14 18:41:35 +08:00
__pudp_idte(addr, pudp, IDTE_LOCAL);
s390/mm: add support for 2GB hugepages This adds support for 2GB hugetlbfs pages on s390. Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-07-04 20:47:01 +08:00
else
s390/mm: merge local / non-local IDTE helper Merge the __p[m|u]xdp_idte and __p[m|u]dp_idte_local functions into a single __p[m|u]dp_idte function with an additional parameter. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-14 18:41:35 +08:00
__pudp_idte(addr, pudp, IDTE_GLOBAL);
s390/mm: add support for 2GB hugepages This adds support for 2GB hugetlbfs pages on s390. Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-07-04 20:47:01 +08:00
atomic_dec(&mm->context.flush_count);
return old;
}
pud_t pudp_xchg_direct(struct mm_struct *mm, unsigned long addr,
pud_t *pudp, pud_t new)
{
pud_t old;
preempt_disable();
old = pudp_flush_direct(mm, addr, pudp);
*pudp = new;
preempt_enable();
return old;
}
EXPORT_SYMBOL(pudp_xchg_direct);
thp, s390: thp splitting backend for s390 This patch is part of the architecture backend for thp on s390. It provides the functions related to thp splitting, including serialization against gup. Unlike other archs, pmdp_splitting_flush() cannot use a tlb flushing operation to serialize against gup on s390, because that wouldn't be stopped by the disabled IRQs. So instead, smp_call_function() is called with an empty function, which will have the expected effect. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: 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>
2012-10-09 07:30:15 +08:00
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
mm/THP: add pmd args to pgtable deposit and withdraw APIs This will be later used by powerpc THP support. In powerpc we want to use pgtable for storing the hash index values. So instead of adding them to mm_context list, we would like to store them in the second half of pmd Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Andrea Arcangeli <aarcange@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-06 08:14:02 +08:00
void pgtable_trans_huge_deposit(struct mm_struct *mm, pmd_t *pmdp,
pgtable_t pgtable)
thp, s390: thp pagetable pre-allocation for s390 This patch is part of the architecture backend for thp on s390. It provides the pagetable pre-allocation functions pgtable_trans_huge_deposit() and pgtable_trans_huge_withdraw(). Unlike other archs, s390 has no struct page * as pgtable_t, but rather a pointer to the page table. So instead of saving the pagetable pre- allocation list info inside the struct page, it is being saved within the pagetable itself. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: 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>
2012-10-09 07:30:18 +08:00
{
struct list_head *lh = (struct list_head *) pgtable;
s390/mm: enable split page table lock for PMD level Add the pgtable_pmd_page_ctor/pgtable_pmd_page_dtor calls to the pmd allocation and free functions and enable ARCH_ENABLE_SPLIT_PMD_PTLOCK for 64 bit. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-02-12 21:16:18 +08:00
assert_spin_locked(pmd_lockptr(mm, pmdp));
thp, s390: thp pagetable pre-allocation for s390 This patch is part of the architecture backend for thp on s390. It provides the pagetable pre-allocation functions pgtable_trans_huge_deposit() and pgtable_trans_huge_withdraw(). Unlike other archs, s390 has no struct page * as pgtable_t, but rather a pointer to the page table. So instead of saving the pagetable pre- allocation list info inside the struct page, it is being saved within the pagetable itself. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: 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>
2012-10-09 07:30:18 +08:00
/* FIFO */
mm, thp: do not access mm->pmd_huge_pte directly Currently mm->pmd_huge_pte protected by page table lock. It will not work with split lock. We have to have per-pmd pmd_huge_pte for proper access serialization. For now, let's just introduce wrapper to access mm->pmd_huge_pte. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Tested-by: Alex Thorlton <athorlton@sgi.com> Cc: Alex Thorlton <athorlton@sgi.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Dave Jones <davej@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kees Cook <keescook@chromium.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Robin Holt <robinmholt@gmail.com> Cc: Sedat Dilek <sedat.dilek@gmail.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-15 06:30:59 +08:00
if (!pmd_huge_pte(mm, pmdp))
thp, s390: thp pagetable pre-allocation for s390 This patch is part of the architecture backend for thp on s390. It provides the pagetable pre-allocation functions pgtable_trans_huge_deposit() and pgtable_trans_huge_withdraw(). Unlike other archs, s390 has no struct page * as pgtable_t, but rather a pointer to the page table. So instead of saving the pagetable pre- allocation list info inside the struct page, it is being saved within the pagetable itself. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: 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>
2012-10-09 07:30:18 +08:00
INIT_LIST_HEAD(lh);
else
mm, thp: do not access mm->pmd_huge_pte directly Currently mm->pmd_huge_pte protected by page table lock. It will not work with split lock. We have to have per-pmd pmd_huge_pte for proper access serialization. For now, let's just introduce wrapper to access mm->pmd_huge_pte. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Tested-by: Alex Thorlton <athorlton@sgi.com> Cc: Alex Thorlton <athorlton@sgi.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Dave Jones <davej@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kees Cook <keescook@chromium.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Robin Holt <robinmholt@gmail.com> Cc: Sedat Dilek <sedat.dilek@gmail.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-15 06:30:59 +08:00
list_add(lh, (struct list_head *) pmd_huge_pte(mm, pmdp));
pmd_huge_pte(mm, pmdp) = pgtable;
thp, s390: thp pagetable pre-allocation for s390 This patch is part of the architecture backend for thp on s390. It provides the pagetable pre-allocation functions pgtable_trans_huge_deposit() and pgtable_trans_huge_withdraw(). Unlike other archs, s390 has no struct page * as pgtable_t, but rather a pointer to the page table. So instead of saving the pagetable pre- allocation list info inside the struct page, it is being saved within the pagetable itself. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: 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>
2012-10-09 07:30:18 +08:00
}
mm/THP: add pmd args to pgtable deposit and withdraw APIs This will be later used by powerpc THP support. In powerpc we want to use pgtable for storing the hash index values. So instead of adding them to mm_context list, we would like to store them in the second half of pmd Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Reviewed-by: Andrea Arcangeli <aarcange@redhat.com> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-06 08:14:02 +08:00
pgtable_t pgtable_trans_huge_withdraw(struct mm_struct *mm, pmd_t *pmdp)
thp, s390: thp pagetable pre-allocation for s390 This patch is part of the architecture backend for thp on s390. It provides the pagetable pre-allocation functions pgtable_trans_huge_deposit() and pgtable_trans_huge_withdraw(). Unlike other archs, s390 has no struct page * as pgtable_t, but rather a pointer to the page table. So instead of saving the pagetable pre- allocation list info inside the struct page, it is being saved within the pagetable itself. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: 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>
2012-10-09 07:30:18 +08:00
{
struct list_head *lh;
pgtable_t pgtable;
pte_t *ptep;
s390/mm: enable split page table lock for PMD level Add the pgtable_pmd_page_ctor/pgtable_pmd_page_dtor calls to the pmd allocation and free functions and enable ARCH_ENABLE_SPLIT_PMD_PTLOCK for 64 bit. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2014-02-12 21:16:18 +08:00
assert_spin_locked(pmd_lockptr(mm, pmdp));
thp, s390: thp pagetable pre-allocation for s390 This patch is part of the architecture backend for thp on s390. It provides the pagetable pre-allocation functions pgtable_trans_huge_deposit() and pgtable_trans_huge_withdraw(). Unlike other archs, s390 has no struct page * as pgtable_t, but rather a pointer to the page table. So instead of saving the pagetable pre- allocation list info inside the struct page, it is being saved within the pagetable itself. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: 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>
2012-10-09 07:30:18 +08:00
/* FIFO */
mm, thp: do not access mm->pmd_huge_pte directly Currently mm->pmd_huge_pte protected by page table lock. It will not work with split lock. We have to have per-pmd pmd_huge_pte for proper access serialization. For now, let's just introduce wrapper to access mm->pmd_huge_pte. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Tested-by: Alex Thorlton <athorlton@sgi.com> Cc: Alex Thorlton <athorlton@sgi.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Dave Jones <davej@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kees Cook <keescook@chromium.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Robin Holt <robinmholt@gmail.com> Cc: Sedat Dilek <sedat.dilek@gmail.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-15 06:30:59 +08:00
pgtable = pmd_huge_pte(mm, pmdp);
thp, s390: thp pagetable pre-allocation for s390 This patch is part of the architecture backend for thp on s390. It provides the pagetable pre-allocation functions pgtable_trans_huge_deposit() and pgtable_trans_huge_withdraw(). Unlike other archs, s390 has no struct page * as pgtable_t, but rather a pointer to the page table. So instead of saving the pagetable pre- allocation list info inside the struct page, it is being saved within the pagetable itself. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: 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>
2012-10-09 07:30:18 +08:00
lh = (struct list_head *) pgtable;
if (list_empty(lh))
mm, thp: do not access mm->pmd_huge_pte directly Currently mm->pmd_huge_pte protected by page table lock. It will not work with split lock. We have to have per-pmd pmd_huge_pte for proper access serialization. For now, let's just introduce wrapper to access mm->pmd_huge_pte. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Tested-by: Alex Thorlton <athorlton@sgi.com> Cc: Alex Thorlton <athorlton@sgi.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Dave Jones <davej@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kees Cook <keescook@chromium.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Robin Holt <robinmholt@gmail.com> Cc: Sedat Dilek <sedat.dilek@gmail.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-15 06:30:59 +08:00
pmd_huge_pte(mm, pmdp) = NULL;
thp, s390: thp pagetable pre-allocation for s390 This patch is part of the architecture backend for thp on s390. It provides the pagetable pre-allocation functions pgtable_trans_huge_deposit() and pgtable_trans_huge_withdraw(). Unlike other archs, s390 has no struct page * as pgtable_t, but rather a pointer to the page table. So instead of saving the pagetable pre- allocation list info inside the struct page, it is being saved within the pagetable itself. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: 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>
2012-10-09 07:30:18 +08:00
else {
mm, thp: do not access mm->pmd_huge_pte directly Currently mm->pmd_huge_pte protected by page table lock. It will not work with split lock. We have to have per-pmd pmd_huge_pte for proper access serialization. For now, let's just introduce wrapper to access mm->pmd_huge_pte. Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Tested-by: Alex Thorlton <athorlton@sgi.com> Cc: Alex Thorlton <athorlton@sgi.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Dave Jones <davej@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kees Cook <keescook@chromium.org> Cc: Mel Gorman <mgorman@suse.de> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Robin Holt <robinmholt@gmail.com> Cc: Sedat Dilek <sedat.dilek@gmail.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-15 06:30:59 +08:00
pmd_huge_pte(mm, pmdp) = (pgtable_t) lh->next;
thp, s390: thp pagetable pre-allocation for s390 This patch is part of the architecture backend for thp on s390. It provides the pagetable pre-allocation functions pgtable_trans_huge_deposit() and pgtable_trans_huge_withdraw(). Unlike other archs, s390 has no struct page * as pgtable_t, but rather a pointer to the page table. So instead of saving the pagetable pre- allocation list info inside the struct page, it is being saved within the pagetable itself. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: 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>
2012-10-09 07:30:18 +08:00
list_del(lh);
}
ptep = (pte_t *) pgtable;
s390/mm: cleanup page table definitions 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>
2013-07-24 02:57:57 +08:00
pte_val(*ptep) = _PAGE_INVALID;
thp, s390: thp pagetable pre-allocation for s390 This patch is part of the architecture backend for thp on s390. It provides the pagetable pre-allocation functions pgtable_trans_huge_deposit() and pgtable_trans_huge_withdraw(). Unlike other archs, s390 has no struct page * as pgtable_t, but rather a pointer to the page table. So instead of saving the pagetable pre- allocation list info inside the struct page, it is being saved within the pagetable itself. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: 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>
2012-10-09 07:30:18 +08:00
ptep++;
s390/mm: cleanup page table definitions 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>
2013-07-24 02:57:57 +08:00
pte_val(*ptep) = _PAGE_INVALID;
thp, s390: thp pagetable pre-allocation for s390 This patch is part of the architecture backend for thp on s390. It provides the pagetable pre-allocation functions pgtable_trans_huge_deposit() and pgtable_trans_huge_withdraw(). Unlike other archs, s390 has no struct page * as pgtable_t, but rather a pointer to the page table. So instead of saving the pagetable pre- allocation list info inside the struct page, it is being saved within the pagetable itself. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: 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>
2012-10-09 07:30:18 +08:00
return pgtable;
}
thp, s390: thp splitting backend for s390 This patch is part of the architecture backend for thp on s390. It provides the functions related to thp splitting, including serialization against gup. Unlike other archs, pmdp_splitting_flush() cannot use a tlb flushing operation to serialize against gup on s390, because that wouldn't be stopped by the disabled IRQs. So instead, smp_call_function() is called with an empty function, which will have the expected effect. Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: 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>
2012-10-09 07:30:15 +08:00
#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
#ifdef CONFIG_PGSTE
void ptep_set_pte_at(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, pte_t entry)
{
pgste_t pgste;
/* the mm_has_pgste() check is done in set_pte_at() */
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_disable();
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
pgste = pgste_get_lock(ptep);
pgste_val(pgste) &= ~_PGSTE_GPS_ZERO;
pgste_set_key(ptep, pgste, entry, mm);
pgste = pgste_set_pte(ptep, pgste, entry);
pgste_set_unlock(ptep, pgste);
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_enable();
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
}
void ptep_set_notify(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
pgste_t pgste;
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_disable();
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
pgste = pgste_get_lock(ptep);
pgste_val(pgste) |= PGSTE_IN_BIT;
pgste_set_unlock(ptep, pgste);
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_enable();
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
}
s390/mm: extended gmap pte notifier The current gmap pte notifier forces a pte into to a read-write state. If the pte is invalidated the gmap notifier is called to inform KVM that the mapping will go away. Extend this approach to allow read-write, read-only and no-access as possible target states and call the pte notifier for any change to the pte. This mechanism is used to temporarily set specific access rights for a pte without doing the heavy work of a true mprotect call. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 18:54:42 +08:00
/**
* ptep_force_prot - change access rights of a locked pte
* @mm: pointer to the process mm_struct
* @addr: virtual address in the guest address space
* @ptep: pointer to the page table entry
* @prot: indicates guest access rights: PROT_NONE, PROT_READ or PROT_WRITE
s390/mm: add shadow gmap support For a nested KVM guest the outer KVM host needs to create shadow page tables for the nested guest. This patch adds the basic support to the guest address space (gmap) code. For each guest address space the inner KVM host creates, the first outer KVM host needs to create shadow page tables. The address space is identified by the ASCE loaded into the control register 1 at the time the inner SIE instruction for the second nested KVM guest is executed. The outer KVM host creates the shadow tables starting with the table identified by the ASCE on a on-demand basis. The outer KVM host will get repeated faults for all the shadow tables needed to run the second KVM guest. While a shadow page table for the second KVM guest is active the access to the origin region, segment and page tables needs to be restricted for the first KVM guest. For region and segment and page tables the first KVM guest may read the memory, but write attempt has to lead to an unshadow. This is done using the page invalid and read-only bits in the page table of the first KVM guest. If the first guest re-accesses one of the origin pages of a shadow, it gets a fault and the affected parts of the shadow page table hierarchy needs to be removed again. PGSTE tables don't have to be shadowed, as all interpretation assist can't deal with the invalid bits in the shadow pte being set differently than the original ones provided by the first KVM guest. Many bug fixes and improvements by David Hildenbrand. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:12:18 +08:00
* @bit: pgste bit to set (e.g. for notification)
s390/mm: extended gmap pte notifier The current gmap pte notifier forces a pte into to a read-write state. If the pte is invalidated the gmap notifier is called to inform KVM that the mapping will go away. Extend this approach to allow read-write, read-only and no-access as possible target states and call the pte notifier for any change to the pte. This mechanism is used to temporarily set specific access rights for a pte without doing the heavy work of a true mprotect call. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 18:54:42 +08:00
*
* Returns 0 if the access rights were changed and -EAGAIN if the current
* and requested access rights are incompatible.
*/
int ptep_force_prot(struct mm_struct *mm, unsigned long addr,
s390/mm: add shadow gmap support For a nested KVM guest the outer KVM host needs to create shadow page tables for the nested guest. This patch adds the basic support to the guest address space (gmap) code. For each guest address space the inner KVM host creates, the first outer KVM host needs to create shadow page tables. The address space is identified by the ASCE loaded into the control register 1 at the time the inner SIE instruction for the second nested KVM guest is executed. The outer KVM host creates the shadow tables starting with the table identified by the ASCE on a on-demand basis. The outer KVM host will get repeated faults for all the shadow tables needed to run the second KVM guest. While a shadow page table for the second KVM guest is active the access to the origin region, segment and page tables needs to be restricted for the first KVM guest. For region and segment and page tables the first KVM guest may read the memory, but write attempt has to lead to an unshadow. This is done using the page invalid and read-only bits in the page table of the first KVM guest. If the first guest re-accesses one of the origin pages of a shadow, it gets a fault and the affected parts of the shadow page table hierarchy needs to be removed again. PGSTE tables don't have to be shadowed, as all interpretation assist can't deal with the invalid bits in the shadow pte being set differently than the original ones provided by the first KVM guest. Many bug fixes and improvements by David Hildenbrand. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:12:18 +08:00
pte_t *ptep, int prot, unsigned long bit)
s390/mm: extended gmap pte notifier The current gmap pte notifier forces a pte into to a read-write state. If the pte is invalidated the gmap notifier is called to inform KVM that the mapping will go away. Extend this approach to allow read-write, read-only and no-access as possible target states and call the pte notifier for any change to the pte. This mechanism is used to temporarily set specific access rights for a pte without doing the heavy work of a true mprotect call. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 18:54:42 +08:00
{
pte_t entry;
pgste_t pgste;
int pte_i, pte_p;
pgste = pgste_get_lock(ptep);
entry = *ptep;
/* Check pte entry after all locks have been acquired */
pte_i = pte_val(entry) & _PAGE_INVALID;
pte_p = pte_val(entry) & _PAGE_PROTECT;
if ((pte_i && (prot != PROT_NONE)) ||
(pte_p && (prot & PROT_WRITE))) {
pgste_set_unlock(ptep, pgste);
return -EAGAIN;
}
s390/mm: add shadow gmap support For a nested KVM guest the outer KVM host needs to create shadow page tables for the nested guest. This patch adds the basic support to the guest address space (gmap) code. For each guest address space the inner KVM host creates, the first outer KVM host needs to create shadow page tables. The address space is identified by the ASCE loaded into the control register 1 at the time the inner SIE instruction for the second nested KVM guest is executed. The outer KVM host creates the shadow tables starting with the table identified by the ASCE on a on-demand basis. The outer KVM host will get repeated faults for all the shadow tables needed to run the second KVM guest. While a shadow page table for the second KVM guest is active the access to the origin region, segment and page tables needs to be restricted for the first KVM guest. For region and segment and page tables the first KVM guest may read the memory, but write attempt has to lead to an unshadow. This is done using the page invalid and read-only bits in the page table of the first KVM guest. If the first guest re-accesses one of the origin pages of a shadow, it gets a fault and the affected parts of the shadow page table hierarchy needs to be removed again. PGSTE tables don't have to be shadowed, as all interpretation assist can't deal with the invalid bits in the shadow pte being set differently than the original ones provided by the first KVM guest. Many bug fixes and improvements by David Hildenbrand. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:12:18 +08:00
/* Change access rights and set pgste bit */
s390/mm: extended gmap pte notifier The current gmap pte notifier forces a pte into to a read-write state. If the pte is invalidated the gmap notifier is called to inform KVM that the mapping will go away. Extend this approach to allow read-write, read-only and no-access as possible target states and call the pte notifier for any change to the pte. This mechanism is used to temporarily set specific access rights for a pte without doing the heavy work of a true mprotect call. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 18:54:42 +08:00
if (prot == PROT_NONE && !pte_i) {
ptep_flush_direct(mm, addr, ptep);
pgste = pgste_update_all(entry, pgste, mm);
pte_val(entry) |= _PAGE_INVALID;
}
if (prot == PROT_READ && !pte_p) {
ptep_flush_direct(mm, addr, ptep);
pte_val(entry) &= ~_PAGE_INVALID;
pte_val(entry) |= _PAGE_PROTECT;
}
s390/mm: add shadow gmap support For a nested KVM guest the outer KVM host needs to create shadow page tables for the nested guest. This patch adds the basic support to the guest address space (gmap) code. For each guest address space the inner KVM host creates, the first outer KVM host needs to create shadow page tables. The address space is identified by the ASCE loaded into the control register 1 at the time the inner SIE instruction for the second nested KVM guest is executed. The outer KVM host creates the shadow tables starting with the table identified by the ASCE on a on-demand basis. The outer KVM host will get repeated faults for all the shadow tables needed to run the second KVM guest. While a shadow page table for the second KVM guest is active the access to the origin region, segment and page tables needs to be restricted for the first KVM guest. For region and segment and page tables the first KVM guest may read the memory, but write attempt has to lead to an unshadow. This is done using the page invalid and read-only bits in the page table of the first KVM guest. If the first guest re-accesses one of the origin pages of a shadow, it gets a fault and the affected parts of the shadow page table hierarchy needs to be removed again. PGSTE tables don't have to be shadowed, as all interpretation assist can't deal with the invalid bits in the shadow pte being set differently than the original ones provided by the first KVM guest. Many bug fixes and improvements by David Hildenbrand. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:12:18 +08:00
pgste_val(pgste) |= bit;
s390/mm: extended gmap pte notifier The current gmap pte notifier forces a pte into to a read-write state. If the pte is invalidated the gmap notifier is called to inform KVM that the mapping will go away. Extend this approach to allow read-write, read-only and no-access as possible target states and call the pte notifier for any change to the pte. This mechanism is used to temporarily set specific access rights for a pte without doing the heavy work of a true mprotect call. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 18:54:42 +08:00
pgste = pgste_set_pte(ptep, pgste, entry);
pgste_set_unlock(ptep, pgste);
return 0;
}
s390/mm: add shadow gmap support For a nested KVM guest the outer KVM host needs to create shadow page tables for the nested guest. This patch adds the basic support to the guest address space (gmap) code. For each guest address space the inner KVM host creates, the first outer KVM host needs to create shadow page tables. The address space is identified by the ASCE loaded into the control register 1 at the time the inner SIE instruction for the second nested KVM guest is executed. The outer KVM host creates the shadow tables starting with the table identified by the ASCE on a on-demand basis. The outer KVM host will get repeated faults for all the shadow tables needed to run the second KVM guest. While a shadow page table for the second KVM guest is active the access to the origin region, segment and page tables needs to be restricted for the first KVM guest. For region and segment and page tables the first KVM guest may read the memory, but write attempt has to lead to an unshadow. This is done using the page invalid and read-only bits in the page table of the first KVM guest. If the first guest re-accesses one of the origin pages of a shadow, it gets a fault and the affected parts of the shadow page table hierarchy needs to be removed again. PGSTE tables don't have to be shadowed, as all interpretation assist can't deal with the invalid bits in the shadow pte being set differently than the original ones provided by the first KVM guest. Many bug fixes and improvements by David Hildenbrand. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:12:18 +08:00
int ptep_shadow_pte(struct mm_struct *mm, unsigned long saddr,
s390/mm: shadow pages with real guest requested protection We really want to avoid manually handling protection for nested virtualization. By shadowing pages with the protection the guest asked us for, the SIE can handle most protection-related actions for us (e.g. special handling for MVPG) and we can directly forward protection exceptions to the guest. PTEs will now always be shadowed with the correct _PAGE_PROTECT flag. Unshadowing will take care of any guest changes to the parent PTE and any host changes to the host PTE. If the host PTE doesn't have the fitting access rights or is not available, we have to fix it up. Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:21:41 +08:00
pte_t *sptep, pte_t *tptep, pte_t pte)
s390/mm: add shadow gmap support For a nested KVM guest the outer KVM host needs to create shadow page tables for the nested guest. This patch adds the basic support to the guest address space (gmap) code. For each guest address space the inner KVM host creates, the first outer KVM host needs to create shadow page tables. The address space is identified by the ASCE loaded into the control register 1 at the time the inner SIE instruction for the second nested KVM guest is executed. The outer KVM host creates the shadow tables starting with the table identified by the ASCE on a on-demand basis. The outer KVM host will get repeated faults for all the shadow tables needed to run the second KVM guest. While a shadow page table for the second KVM guest is active the access to the origin region, segment and page tables needs to be restricted for the first KVM guest. For region and segment and page tables the first KVM guest may read the memory, but write attempt has to lead to an unshadow. This is done using the page invalid and read-only bits in the page table of the first KVM guest. If the first guest re-accesses one of the origin pages of a shadow, it gets a fault and the affected parts of the shadow page table hierarchy needs to be removed again. PGSTE tables don't have to be shadowed, as all interpretation assist can't deal with the invalid bits in the shadow pte being set differently than the original ones provided by the first KVM guest. Many bug fixes and improvements by David Hildenbrand. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:12:18 +08:00
{
pgste_t spgste, tpgste;
pte_t spte, tpte;
int rc = -EAGAIN;
s390/mm: shadow pages with real guest requested protection We really want to avoid manually handling protection for nested virtualization. By shadowing pages with the protection the guest asked us for, the SIE can handle most protection-related actions for us (e.g. special handling for MVPG) and we can directly forward protection exceptions to the guest. PTEs will now always be shadowed with the correct _PAGE_PROTECT flag. Unshadowing will take care of any guest changes to the parent PTE and any host changes to the host PTE. If the host PTE doesn't have the fitting access rights or is not available, we have to fix it up. Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:21:41 +08:00
if (!(pte_val(*tptep) & _PAGE_INVALID))
return 0; /* already shadowed */
s390/mm: add shadow gmap support For a nested KVM guest the outer KVM host needs to create shadow page tables for the nested guest. This patch adds the basic support to the guest address space (gmap) code. For each guest address space the inner KVM host creates, the first outer KVM host needs to create shadow page tables. The address space is identified by the ASCE loaded into the control register 1 at the time the inner SIE instruction for the second nested KVM guest is executed. The outer KVM host creates the shadow tables starting with the table identified by the ASCE on a on-demand basis. The outer KVM host will get repeated faults for all the shadow tables needed to run the second KVM guest. While a shadow page table for the second KVM guest is active the access to the origin region, segment and page tables needs to be restricted for the first KVM guest. For region and segment and page tables the first KVM guest may read the memory, but write attempt has to lead to an unshadow. This is done using the page invalid and read-only bits in the page table of the first KVM guest. If the first guest re-accesses one of the origin pages of a shadow, it gets a fault and the affected parts of the shadow page table hierarchy needs to be removed again. PGSTE tables don't have to be shadowed, as all interpretation assist can't deal with the invalid bits in the shadow pte being set differently than the original ones provided by the first KVM guest. Many bug fixes and improvements by David Hildenbrand. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:12:18 +08:00
spgste = pgste_get_lock(sptep);
spte = *sptep;
if (!(pte_val(spte) & _PAGE_INVALID) &&
s390/mm: shadow pages with real guest requested protection We really want to avoid manually handling protection for nested virtualization. By shadowing pages with the protection the guest asked us for, the SIE can handle most protection-related actions for us (e.g. special handling for MVPG) and we can directly forward protection exceptions to the guest. PTEs will now always be shadowed with the correct _PAGE_PROTECT flag. Unshadowing will take care of any guest changes to the parent PTE and any host changes to the host PTE. If the host PTE doesn't have the fitting access rights or is not available, we have to fix it up. Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:21:41 +08:00
!((pte_val(spte) & _PAGE_PROTECT) &&
!(pte_val(pte) & _PAGE_PROTECT))) {
s390/mm: add shadow gmap support For a nested KVM guest the outer KVM host needs to create shadow page tables for the nested guest. This patch adds the basic support to the guest address space (gmap) code. For each guest address space the inner KVM host creates, the first outer KVM host needs to create shadow page tables. The address space is identified by the ASCE loaded into the control register 1 at the time the inner SIE instruction for the second nested KVM guest is executed. The outer KVM host creates the shadow tables starting with the table identified by the ASCE on a on-demand basis. The outer KVM host will get repeated faults for all the shadow tables needed to run the second KVM guest. While a shadow page table for the second KVM guest is active the access to the origin region, segment and page tables needs to be restricted for the first KVM guest. For region and segment and page tables the first KVM guest may read the memory, but write attempt has to lead to an unshadow. This is done using the page invalid and read-only bits in the page table of the first KVM guest. If the first guest re-accesses one of the origin pages of a shadow, it gets a fault and the affected parts of the shadow page table hierarchy needs to be removed again. PGSTE tables don't have to be shadowed, as all interpretation assist can't deal with the invalid bits in the shadow pte being set differently than the original ones provided by the first KVM guest. Many bug fixes and improvements by David Hildenbrand. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:12:18 +08:00
pgste_val(spgste) |= PGSTE_VSIE_BIT;
tpgste = pgste_get_lock(tptep);
pte_val(tpte) = (pte_val(spte) & PAGE_MASK) |
s390/mm: shadow pages with real guest requested protection We really want to avoid manually handling protection for nested virtualization. By shadowing pages with the protection the guest asked us for, the SIE can handle most protection-related actions for us (e.g. special handling for MVPG) and we can directly forward protection exceptions to the guest. PTEs will now always be shadowed with the correct _PAGE_PROTECT flag. Unshadowing will take care of any guest changes to the parent PTE and any host changes to the host PTE. If the host PTE doesn't have the fitting access rights or is not available, we have to fix it up. Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:21:41 +08:00
(pte_val(pte) & _PAGE_PROTECT);
s390/mm: add shadow gmap support For a nested KVM guest the outer KVM host needs to create shadow page tables for the nested guest. This patch adds the basic support to the guest address space (gmap) code. For each guest address space the inner KVM host creates, the first outer KVM host needs to create shadow page tables. The address space is identified by the ASCE loaded into the control register 1 at the time the inner SIE instruction for the second nested KVM guest is executed. The outer KVM host creates the shadow tables starting with the table identified by the ASCE on a on-demand basis. The outer KVM host will get repeated faults for all the shadow tables needed to run the second KVM guest. While a shadow page table for the second KVM guest is active the access to the origin region, segment and page tables needs to be restricted for the first KVM guest. For region and segment and page tables the first KVM guest may read the memory, but write attempt has to lead to an unshadow. This is done using the page invalid and read-only bits in the page table of the first KVM guest. If the first guest re-accesses one of the origin pages of a shadow, it gets a fault and the affected parts of the shadow page table hierarchy needs to be removed again. PGSTE tables don't have to be shadowed, as all interpretation assist can't deal with the invalid bits in the shadow pte being set differently than the original ones provided by the first KVM guest. Many bug fixes and improvements by David Hildenbrand. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:12:18 +08:00
/* don't touch the storage key - it belongs to parent pgste */
tpgste = pgste_set_pte(tptep, tpgste, tpte);
pgste_set_unlock(tptep, tpgste);
s390/mm: shadow pages with real guest requested protection We really want to avoid manually handling protection for nested virtualization. By shadowing pages with the protection the guest asked us for, the SIE can handle most protection-related actions for us (e.g. special handling for MVPG) and we can directly forward protection exceptions to the guest. PTEs will now always be shadowed with the correct _PAGE_PROTECT flag. Unshadowing will take care of any guest changes to the parent PTE and any host changes to the host PTE. If the host PTE doesn't have the fitting access rights or is not available, we have to fix it up. Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:21:41 +08:00
rc = 1;
s390/mm: add shadow gmap support For a nested KVM guest the outer KVM host needs to create shadow page tables for the nested guest. This patch adds the basic support to the guest address space (gmap) code. For each guest address space the inner KVM host creates, the first outer KVM host needs to create shadow page tables. The address space is identified by the ASCE loaded into the control register 1 at the time the inner SIE instruction for the second nested KVM guest is executed. The outer KVM host creates the shadow tables starting with the table identified by the ASCE on a on-demand basis. The outer KVM host will get repeated faults for all the shadow tables needed to run the second KVM guest. While a shadow page table for the second KVM guest is active the access to the origin region, segment and page tables needs to be restricted for the first KVM guest. For region and segment and page tables the first KVM guest may read the memory, but write attempt has to lead to an unshadow. This is done using the page invalid and read-only bits in the page table of the first KVM guest. If the first guest re-accesses one of the origin pages of a shadow, it gets a fault and the affected parts of the shadow page table hierarchy needs to be removed again. PGSTE tables don't have to be shadowed, as all interpretation assist can't deal with the invalid bits in the shadow pte being set differently than the original ones provided by the first KVM guest. Many bug fixes and improvements by David Hildenbrand. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 19:12:18 +08:00
}
pgste_set_unlock(sptep, spgste);
return rc;
}
void ptep_unshadow_pte(struct mm_struct *mm, unsigned long saddr, pte_t *ptep)
{
pgste_t pgste;
pgste = pgste_get_lock(ptep);
/* notifier is called by the caller */
ptep_flush_direct(mm, saddr, ptep);
/* don't touch the storage key - it belongs to parent pgste */
pgste = pgste_set_pte(ptep, pgste, __pte(_PAGE_INVALID));
pgste_set_unlock(ptep, pgste);
}
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
static void ptep_zap_swap_entry(struct mm_struct *mm, swp_entry_t entry)
{
if (!non_swap_entry(entry))
dec_mm_counter(mm, MM_SWAPENTS);
else if (is_migration_entry(entry)) {
struct page *page = migration_entry_to_page(entry);
dec_mm_counter(mm, mm_counter(page));
}
free_swap_and_cache(entry);
}
void ptep_zap_unused(struct mm_struct *mm, unsigned long addr,
pte_t *ptep, int reset)
{
unsigned long pgstev;
pgste_t pgste;
pte_t pte;
/* Zap unused and logically-zero pages */
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_disable();
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
pgste = pgste_get_lock(ptep);
pgstev = pgste_val(pgste);
pte = *ptep;
KVM: s390/mm: Fix CMMA reset during reboot commit 1e133ab296f ("s390/mm: split arch/s390/mm/pgtable.c") factored out the page table handling code from __gmap_zap and __s390_reset_cmma into ptep_zap_unused and added a simple flag that tells which one of the function (reset or not) is to be made. This also changed the behaviour, as it also zaps unused page table entries on reset. Turns out that this is wrong as s390_reset_cmma uses the page walker, which DOES NOT take the ptl lock. The most simple fix is to not do the zapping part on reset (which uses the walker) Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Fixes: 1e133ab296f ("s390/mm: split arch/s390/mm/pgtable.c") Cc: stable@vger.kernel.org # 4.6+ Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-13 19:14:56 +08:00
if (!reset && pte_swap(pte) &&
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
((pgstev & _PGSTE_GPS_USAGE_MASK) == _PGSTE_GPS_USAGE_UNUSED ||
(pgstev & _PGSTE_GPS_ZERO))) {
ptep_zap_swap_entry(mm, pte_to_swp_entry(pte));
pte_clear(mm, addr, ptep);
}
if (reset)
pgste_val(pgste) &= ~_PGSTE_GPS_USAGE_MASK;
pgste_set_unlock(ptep, pgste);
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_enable();
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
}
void ptep_zap_key(struct mm_struct *mm, unsigned long addr, pte_t *ptep)
{
unsigned long ptev;
pgste_t pgste;
/* Clear storage key */
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_disable();
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
pgste = pgste_get_lock(ptep);
pgste_val(pgste) &= ~(PGSTE_ACC_BITS | PGSTE_FP_BIT |
PGSTE_GR_BIT | PGSTE_GC_BIT);
ptev = pte_val(*ptep);
if (!(ptev & _PAGE_INVALID) && (ptev & _PAGE_WRITE))
page_set_storage_key(ptev & PAGE_MASK, PAGE_DEFAULT_KEY, 1);
pgste_set_unlock(ptep, pgste);
s390/mm: fix vunmap vs finish_arch_post_lock_switch The vunmap_pte_range() function calls ptep_get_and_clear() without any locking. ptep_get_and_clear() uses ptep_xchg_lazy()/ptep_flush_direct() for the page table update. ptep_flush_direct requires that preemption is disabled, but without any locking this is not the case. If the kernel preempts the task while the attach_counter is increased an endless loop in finish_arch_post_lock_switch() will occur the next time the task is scheduled. Add explicit preempt_disable()/preempt_enable() calls to the relevant functions in arch/s390/mm/pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-06-06 16:30:45 +08:00
preempt_enable();
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
}
/*
* Test and reset if a guest page is dirty
*/
bool test_and_clear_guest_dirty(struct mm_struct *mm, unsigned long addr)
{
spinlock_t *ptl;
pgste_t pgste;
pte_t *ptep;
pte_t pte;
bool dirty;
ptep = get_locked_pte(mm, addr, &ptl);
if (unlikely(!ptep))
return false;
pgste = pgste_get_lock(ptep);
dirty = !!(pgste_val(pgste) & PGSTE_UC_BIT);
pgste_val(pgste) &= ~PGSTE_UC_BIT;
pte = *ptep;
if (dirty && (pte_val(pte) & _PAGE_PRESENT)) {
s390/mm: extended gmap pte notifier The current gmap pte notifier forces a pte into to a read-write state. If the pte is invalidated the gmap notifier is called to inform KVM that the mapping will go away. Extend this approach to allow read-write, read-only and no-access as possible target states and call the pte notifier for any change to the pte. This mechanism is used to temporarily set specific access rights for a pte without doing the heavy work of a true mprotect call. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 18:54:42 +08:00
pgste = pgste_pte_notify(mm, addr, ptep, pgste);
s390/mm: merge local / non-local IPTE helper 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>
2016-06-14 18:38:40 +08:00
__ptep_ipte(addr, ptep, IPTE_GLOBAL);
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
if (MACHINE_HAS_ESOP || !(pte_val(pte) & _PAGE_WRITE))
pte_val(pte) |= _PAGE_PROTECT;
else
pte_val(pte) |= _PAGE_INVALID;
*ptep = pte;
}
pgste_set_unlock(ptep, pgste);
spin_unlock(ptl);
return dirty;
}
EXPORT_SYMBOL_GPL(test_and_clear_guest_dirty);
int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
unsigned char key, bool nq)
{
unsigned long keyul;
spinlock_t *ptl;
pgste_t old, new;
pte_t *ptep;
ptep = get_locked_pte(mm, addr, &ptl);
s390/mm: set and get guest storage key mmap locking Move the mmap semaphore locking out of set_guest_storage_key and get_guest_storage_key. This makes the two functions more like the other ptep_xxx operations and allows to avoid repeated semaphore operations if multiple keys are read or written. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 18:53:35 +08:00
if (unlikely(!ptep))
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
return -EFAULT;
new = old = pgste_get_lock(ptep);
pgste_val(new) &= ~(PGSTE_GR_BIT | PGSTE_GC_BIT |
PGSTE_ACC_BITS | PGSTE_FP_BIT);
keyul = (unsigned long) key;
pgste_val(new) |= (keyul & (_PAGE_CHANGED | _PAGE_REFERENCED)) << 48;
pgste_val(new) |= (keyul & (_PAGE_ACC_BITS | _PAGE_FP_BIT)) << 56;
if (!(pte_val(*ptep) & _PAGE_INVALID)) {
unsigned long address, bits, skey;
address = pte_val(*ptep) & PAGE_MASK;
skey = (unsigned long) page_get_storage_key(address);
bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED);
skey = key & (_PAGE_ACC_BITS | _PAGE_FP_BIT);
/* Set storage key ACC and FP */
page_set_storage_key(address, skey, !nq);
/* Merge host changed & referenced into pgste */
pgste_val(new) |= bits << 52;
}
/* changing the guest storage key is considered a change of the page */
if ((pgste_val(new) ^ pgste_val(old)) &
(PGSTE_ACC_BITS | PGSTE_FP_BIT | PGSTE_GR_BIT | PGSTE_GC_BIT))
pgste_val(new) |= PGSTE_UC_BIT;
pgste_set_unlock(ptep, new);
pte_unmap_unlock(ptep, ptl);
return 0;
}
EXPORT_SYMBOL(set_guest_storage_key);
KVM: s390: pfmf: support conditional-sske facility We already indicate that facility but don't implement it in our pfmf interception handler. Let's add a new storage key handling function for conditionally setting the guest storage key. As we will reuse this function later on, let's directly implement returning the old key via parameter and indicating if any change happened via rc. Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-10 15:43:11 +08:00
/**
* Conditionally set a guest storage key (handling csske).
* oldkey will be updated when either mr or mc is set and a pointer is given.
*
* Returns 0 if a guests storage key update wasn't necessary, 1 if the guest
* storage key was updated and -EFAULT on access errors.
*/
int cond_set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
unsigned char key, unsigned char *oldkey,
bool nq, bool mr, bool mc)
{
unsigned char tmp, mask = _PAGE_ACC_BITS | _PAGE_FP_BIT;
int rc;
/* we can drop the pgste lock between getting and setting the key */
if (mr | mc) {
rc = get_guest_storage_key(current->mm, addr, &tmp);
if (rc)
return rc;
if (oldkey)
*oldkey = tmp;
if (!mr)
mask |= _PAGE_REFERENCED;
if (!mc)
mask |= _PAGE_CHANGED;
if (!((tmp ^ key) & mask))
return 0;
}
rc = set_guest_storage_key(current->mm, addr, key, nq);
return rc < 0 ? rc : 1;
}
EXPORT_SYMBOL(cond_set_guest_storage_key);
KVM: s390: handle missing storage-key facility Without the storage-key facility, SIE won't interpret SSKE, ISKE and RRBE for us. So let's add proper interception handlers that will be called if lazy sske cannot be enabled. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-10 15:50:21 +08:00
/**
* Reset a guest reference bit (rrbe), returning the reference and changed bit.
*
* Returns < 0 in case of error, otherwise the cc to be reported to the guest.
*/
int reset_guest_reference_bit(struct mm_struct *mm, unsigned long addr)
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
{
spinlock_t *ptl;
KVM: s390: handle missing storage-key facility Without the storage-key facility, SIE won't interpret SSKE, ISKE and RRBE for us. So let's add proper interception handlers that will be called if lazy sske cannot be enabled. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-10 15:50:21 +08:00
pgste_t old, new;
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
pte_t *ptep;
KVM: s390: handle missing storage-key facility Without the storage-key facility, SIE won't interpret SSKE, ISKE and RRBE for us. So let's add proper interception handlers that will be called if lazy sske cannot be enabled. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-10 15:50:21 +08:00
int cc = 0;
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
ptep = get_locked_pte(mm, addr, &ptl);
KVM: s390: handle missing storage-key facility Without the storage-key facility, SIE won't interpret SSKE, ISKE and RRBE for us. So let's add proper interception handlers that will be called if lazy sske cannot be enabled. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-10 15:50:21 +08:00
if (unlikely(!ptep))
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
return -EFAULT;
KVM: s390: handle missing storage-key facility Without the storage-key facility, SIE won't interpret SSKE, ISKE and RRBE for us. So let's add proper interception handlers that will be called if lazy sske cannot be enabled. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-10 15:50:21 +08:00
new = old = pgste_get_lock(ptep);
/* Reset guest reference bit only */
pgste_val(new) &= ~PGSTE_GR_BIT;
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
KVM: s390: handle missing storage-key facility Without the storage-key facility, SIE won't interpret SSKE, ISKE and RRBE for us. So let's add proper interception handlers that will be called if lazy sske cannot be enabled. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-10 15:50:21 +08:00
if (!(pte_val(*ptep) & _PAGE_INVALID)) {
cc = page_reset_referenced(pte_val(*ptep) & PAGE_MASK);
/* Merge real referenced bit into host-set */
pgste_val(new) |= ((unsigned long) cc << 53) & PGSTE_HR_BIT;
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
}
KVM: s390: handle missing storage-key facility Without the storage-key facility, SIE won't interpret SSKE, ISKE and RRBE for us. So let's add proper interception handlers that will be called if lazy sske cannot be enabled. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-10 15:50:21 +08:00
/* Reflect guest's logical view, not physical */
cc |= (pgste_val(old) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 49;
/* Changing the guest storage key is considered a change of the page */
if ((pgste_val(new) ^ pgste_val(old)) & PGSTE_GR_BIT)
pgste_val(new) |= PGSTE_UC_BIT;
pgste_set_unlock(ptep, new);
pte_unmap_unlock(ptep, ptl);
return 0;
}
EXPORT_SYMBOL(reset_guest_reference_bit);
s390/mm: return key via pointer in get_guest_storage_key Let's just split returning the key and reporting errors. This makes calling code easier and avoids bugs as happened already. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-09 17:22:34 +08:00
int get_guest_storage_key(struct mm_struct *mm, unsigned long addr,
unsigned char *key)
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
{
spinlock_t *ptl;
pgste_t pgste;
pte_t *ptep;
ptep = get_locked_pte(mm, addr, &ptl);
s390/mm: set and get guest storage key mmap locking Move the mmap semaphore locking out of set_guest_storage_key and get_guest_storage_key. This makes the two functions more like the other ptep_xxx operations and allows to avoid repeated semaphore operations if multiple keys are read or written. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 18:53:35 +08:00
if (unlikely(!ptep))
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
return -EFAULT;
s390/mm: set and get guest storage key mmap locking Move the mmap semaphore locking out of set_guest_storage_key and get_guest_storage_key. This makes the two functions more like the other ptep_xxx operations and allows to avoid repeated semaphore operations if multiple keys are read or written. Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-03-08 18:53:35 +08:00
pgste = pgste_get_lock(ptep);
s390/mm: return key via pointer in get_guest_storage_key Let's just split returning the key and reporting errors. This makes calling code easier and avoids bugs as happened already. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-09 17:22:34 +08:00
*key = (pgste_val(pgste) & (PGSTE_ACC_BITS | PGSTE_FP_BIT)) >> 56;
s390/mm: simplify get_guest_storage_key We can safe a few LOC and make that function easier to understand by rewriting existing code. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-09 17:15:32 +08:00
if (!(pte_val(*ptep) & _PAGE_INVALID))
s390/mm: return key via pointer in get_guest_storage_key Let's just split returning the key and reporting errors. This makes calling code easier and avoids bugs as happened already. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-09 17:22:34 +08:00
*key = page_get_storage_key(pte_val(*ptep) & PAGE_MASK);
s390/mm: simplify get_guest_storage_key We can safe a few LOC and make that function easier to understand by rewriting existing code. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-09 17:15:32 +08:00
/* Reflect guest's logical view, not physical */
s390/mm: return key via pointer in get_guest_storage_key Let's just split returning the key and reporting errors. This makes calling code easier and avoids bugs as happened already. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-09 17:22:34 +08:00
*key |= (pgste_val(pgste) & (PGSTE_GR_BIT | PGSTE_GC_BIT)) >> 48;
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
pgste_set_unlock(ptep, pgste);
pte_unmap_unlock(ptep, ptl);
s390/mm: return key via pointer in get_guest_storage_key Let's just split returning the key and reporting errors. This makes calling code easier and avoids bugs as happened already. Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2016-05-09 17:22:34 +08:00
return 0;
s390/mm: split arch/s390/mm/pgtable.c The pgtable.c file is quite big, before it grows any larger split it into pgtable.c, pgalloc.c and gmap.c. In addition move the gmap related header definitions into the new gmap.h header and all of the pgste helpers from pgtable.h to pgtable.c. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-03-08 18:49:57 +08:00
}
EXPORT_SYMBOL(get_guest_storage_key);
#endif