linux.git/arch/s390/include/asm/pgalloc.h, branch v5.12

s390/mm: fix phys vs virt confusion in pgtable allocation routines

2021-02-23T23:31:22+00:00

The physical address of page tables is passed around and
used as virtual address in various locations.

Signed-off-by: Alexander Gordeev 
Reviewed-by: Heiko Carstens 
Signed-off-by: Vasily Gorbik

s390: remove orphaned function declarations

2020-09-30T10:09:54+00:00

arch/s390/pci/pci_bus.h: zpci_bus_init - only declaration left after
commit 05bc1be6db4b ("s390/pci: create zPCI bus")

arch/s390/include/asm/gmap.h: gmap_pte_notify - only declaration left
after commit 4be130a08420 ("s390/mm: add shadow gmap support")

arch/s390/include/asm/pgalloc.h: rcu_table_freelist_finish - only
declaration left after commit 36409f6353fc ("[S390] use generic RCU
page-table freeing code")

arch/s390/include/asm/tlbflush.h: smp_ptlb_all - only declaration left
after commit 5a79859ae0f3 ("s390: remove 31 bit support")

arch/s390/include/asm/vtimer.h: init_cpu_vtimer - only declaration left
after commit b5f87f15e200 ("s390/idle: consolidate idle functions and
definitions")

arch/s390/include/asm/pci.h: zpci_debug_info - only declaration left
after commit 386aa051fb4b ("s390/pci: remove per device debug attribute")

arch/s390/include/asm/vdso.h: vdso_alloc_boot_cpu - only declaration
left after commit 4bff8cb54502 ("s390: convert to GENERIC_VDSO")

arch/s390/include/asm/smp.h: smp_vcpu_scheduled - only declaration left
after commit 67626fadd269 ("s390: enforce CONFIG_SMP")

arch/s390/kernel/entry.h: restart_call_handler - only declaration left
after commit 8b646bd75908 ("[S390] rework smp code")

arch/s390/kernel/entry.h: startup_init_nobss - only declaration left
after commit 2e83e0eb85ca ("s390: clean .bss before running uncompressed
kernel")

arch/s390/kernel/entry.h: s390_early_resume - only declaration left after
commit 394216275c7d ("s390: remove broken hibernate / power management
support")

drivers/s390/char/raw3270.h: raw3270_request_alloc_bootmem - only
declaration left after commit 33403dcfcdfd ("[S390] 3270 console:
convert from bootmem to slab")

drivers/s390/cio/device.h: ccw_device_schedule_sch_unregister - only
declaration left after commit 37de53bb5290 ("[S390] cio: introduce ccw
device todos")

drivers/s390/char/tape.h: tape_hotplug_event - has only declaration
since recorded git history.

drivers/s390/char/tape.h: tape_oper_handler - has only declaration since
recorded git history.

drivers/s390/char/tape.h: tape_noper_handler - has only declaration
since recorded git history.

drivers/s390/char/tape_std.h: tape_std_check_locate - only declaration
left after commit 161beff8f40d ("s390/tape: remove tape block leftovers")

drivers/s390/char/tape_std.h: tape_std_default_handler - has only
declaration since recorded git history.

drivers/s390/char/tape_std.h: tape_std_unexpect_uchk_handler - has only
declaration since recorded git history.

drivers/s390/char/tape_std.h: tape_std_irq - has only declaration since
recorded git history.

drivers/s390/char/tape_std.h: tape_std_error_recovery - has only
declaration since recorded git history.

drivers/s390/char/tape_std.h: tape_std_error_recovery_has_failed -
has only declaration since recorded git history.

drivers/s390/char/tape_std.h: tape_std_error_recovery_succeded - has
only declaration since recorded git history.

drivers/s390/char/tape_std.h: tape_std_error_recovery_do_retry - has
only declaration since recorded git history.

drivers/s390/char/tape_std.h: tape_std_error_recovery_read_opposite -
has only declaration since recorded git history.

drivers/s390/char/tape_std.h: tape_std_error_recovery_HWBUG - has only
declaration since recorded git history.

Reviewed-by: Sven Schnelle 
Signed-off-by: Vasily Gorbik

s390/mm: cleanup init_new_context() callback

2020-03-28T11:46:12+00:00

The set of values asce_limit may be assigned with is TASK_SIZE_MAX,
_REGION1_SIZE, _REGION2_SIZE and 0 as a special case if the callback
was called from execve().
Do VM_BUG_ON() if asce_limit is something else.

Save few CPU cycles by removing unnecessary asce_limit re-assignment
in case of 3-level task and redundant PGD entry type reconstruction.

Signed-off-by: Alexander Gordeev 
Reviewed-by: Heiko Carstens 
Signed-off-by: Heiko Carstens 
Signed-off-by: Vasily Gorbik

s390/mm: remove page table downgrade support

2020-03-28T11:46:12+00:00

This update consolidates page table handling code. Because
there are hardly any 31-bit binaries left we do not need to
optimize for that.

No extra efforts are needed to ensure that a compat task does
not map anything above 2GB. The TASK_SIZE limit for 31-bit
tasks is 2GB already and the generic code does check that a
resulting map address would not surpass that limit.

Signed-off-by: Alexander Gordeev 
Reviewed-by: Heiko Carstens 
Signed-off-by: Heiko Carstens 
Signed-off-by: Vasily Gorbik

s390/mm: cleanup arch_get_unmapped_area() and friends

2020-03-27T09:22:46+00:00

Factor out check_asce_limit() function and fix few style
defects in arch_get_unmapped_area() family of functions.

Signed-off-by: Alexander Gordeev 
Reviewed-by: Heiko Carstens 
[heiko.carstens@de.ibm.com: small coding style changes]
Signed-off-by: Heiko Carstens 
Signed-off-by: Vasily Gorbik

s390/mm: add mm_pxd_folded() checks to pxd_free()

2019-10-31T16:20:54+00:00

Unlike pxd_free_tlb(), the pxd_free() functions do not check for folded
page tables. This is not an issue so far, as those functions will actually
never be called, since no code will reach them when page tables are folded.

In order to avoid future issues, and to make the s390 code more similar to
other architectures, add mm_pxd_folded() checks, similar to how it is done
in pxd_free_tlb().

This was found by testing a patch from from Anshuman Khandual, which is
currently discussed on LKML ("mm/debug: Add tests validating architecture
page table helpers").

Signed-off-by: Gerald Schaefer 
Signed-off-by: Vasily Gorbik

mm: treewide: remove unused address argument from pte_alloc functions

2019-01-04T21:13:47+00:00

Patch series "Add support for fast mremap".

This series speeds up the mremap(2) syscall by copying page tables at
the PMD level even for non-THP systems.  There is concern that the extra
'address' argument that mremap passes to pte_alloc may do something
subtle architecture related in the future that may make the scheme not
work.  Also we find that there is no point in passing the 'address' to
pte_alloc since its unused.  This patch therefore removes this argument
tree-wide resulting in a nice negative diff as well.  Also ensuring
along the way that the enabled architectures do not do anything funky
with the 'address' argument that goes unnoticed by the optimization.

Build and boot tested on x86-64.  Build tested on arm64.  The config
enablement patch for arm64 will be posted in the future after more
testing.

The changes were obtained by applying the following Coccinelle script.
(thanks Julia for answering all Coccinelle questions!).
Following fix ups were done manually:
* Removal of address argument from  pte_fragment_alloc
* Removal of pte_alloc_one_fast definitions from m68k and microblaze.

// Options: --include-headers --no-includes
// Note: I split the 'identifier fn' line, so if you are manually
// running it, please unsplit it so it runs for you.

virtual patch

@pte_alloc_func_def depends on patch exists@
identifier E2;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
type T2;
@@

 fn(...
- , T2 E2
 )
 { ... }

@pte_alloc_func_proto_noarg depends on patch exists@
type T1, T2, T3, T4;
identifier fn =~ "^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@

(
- T3 fn(T1, T2);
+ T3 fn(T1);
|
- T3 fn(T1, T2, T4);
+ T3 fn(T1, T2);
)

@pte_alloc_func_proto depends on patch exists@
identifier E1, E2, E4;
type T1, T2, T3, T4;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@

(
- T3 fn(T1 E1, T2 E2);
+ T3 fn(T1 E1);
|
- T3 fn(T1 E1, T2 E2, T4 E4);
+ T3 fn(T1 E1, T2 E2);
)

@pte_alloc_func_call depends on patch exists@
expression E2;
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
@@

 fn(...
-,  E2
 )

@pte_alloc_macro depends on patch exists@
identifier fn =~
"^(__pte_alloc|pte_alloc_one|pte_alloc|__pte_alloc_kernel|pte_alloc_one_kernel)$";
identifier a, b, c;
expression e;
position p;
@@

(
- #define fn(a, b, c) e
+ #define fn(a, b) e
|
- #define fn(a, b) e
+ #define fn(a) e
)

Link: http://lkml.kernel.org/r/20181108181201.88826-2-joelaf@google.com
Signed-off-by: Joel Fernandes (Google) 
Suggested-by: Kirill A. Shutemov 
Acked-by: Kirill A. Shutemov 
Cc: Michal Hocko 
Cc: Julia Lawall 
Cc: Kirill A. Shutemov 
Cc: William Kucharski 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

s390/mm: fix mis-accounting of pgtable_bytes

2018-11-02T07:31:55+00:00

In case a fork or a clone system fails in copy_process and the error
handling does the mmput() at the bad_fork_cleanup_mm label, the
following warning messages will appear on the console:

  BUG: non-zero pgtables_bytes on freeing mm: 16384

The reason for that is the tricks we play with mm_inc_nr_puds() and
mm_inc_nr_pmds() in init_new_context().

A normal 64-bit process has 3 levels of page table, the p4d level and
the pud level are folded. On process termination the free_pud_range()
function in mm/memory.c will subtract 16KB from pgtable_bytes with a
mm_dec_nr_puds() call, but there actually is not really a pud table.

One issue with this is the fact that pgtable_bytes is usually off
by a few kilobytes, but the more severe problem is that for a failed
fork or clone the free_pgtables() function is not called. In this case
there is no mm_dec_nr_puds() or mm_dec_nr_pmds() that go together with
the mm_inc_nr_puds() and mm_inc_nr_pmds in init_new_context().
The pgtable_bytes will be off by 16384 or 32768 bytes and we get the
BUG message. The message itself is purely cosmetic, but annoying.

To fix this override the mm_pmd_folded, mm_pud_folded and mm_p4d_folded
function to check for the true size of the address space.

Reported-by: Li Wang 
Tested-by: Li Wang 
Signed-off-by: Martin Schwidefsky

s390/mm: provide base_asce_alloc() / base_asce_free() helper functions

2018-02-22T14:31:23+00:00

Provide base_asce_alloc() and base_asce_free() helper functions which
can be used to allocate an ASCE and all required region, segment and
page tables required to access memory regions of the virtual kernel
address space.

Both, the ASCE and all tables, do not use any features that correspond
to e.g. enhanced DAT features. This is required for some I/O functions
that pass an ASCE, like e.g. some service call requests, but which may
not use any enhanced features.

Acked-by: Peter Oberparleiter 
Acked-by: Janosch Frank 
Signed-off-by: Heiko Carstens 
Signed-off-by: Martin Schwidefsky

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

2017-11-13T19:47:01+00:00

Pull s390 updates from Heiko Carstens:
 "Since Martin is on vacation you get the s390 pull request for the
  v4.15 merge window this time from me.

  Besides a lot of cleanups and bug fixes these are the most important
  changes:

   - a new regset for runtime instrumentation registers

   - hardware accelerated AES-GCM support for the aes_s390 module

   - support for the new CEX6S crypto cards

   - support for FORTIFY_SOURCE

   - addition of missing z13 and new z14 instructions to the in-kernel
     disassembler

   - generate opcode tables for the in-kernel disassembler out of a
     simple text file instead of having to manually maintain those
     tables

   - fast memset16, memset32 and memset64 implementations

   - removal of named saved segment support

   - hardware counter support for z14

   - queued spinlocks and queued rwlocks implementations for s390

   - use the stack_depth tracking feature for s390 BPF JIT

   - a new s390_sthyi system call which emulates the sthyi (store
     hypervisor information) instruction

   - removal of the old KVM virtio transport

   - an s390 specific CPU alternatives implementation which is used in
     the new spinlock code"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (88 commits)
  MAINTAINERS: add virtio-ccw.h to virtio/s390 section
  s390/noexec: execute kexec datamover without DAT
  s390: fix transactional execution control register handling
  s390/bpf: take advantage of stack_depth tracking
  s390: simplify transactional execution elf hwcap handling
  s390/zcrypt: Rework struct ap_qact_ap_info.
  s390/virtio: remove unused header file kvm_virtio.h
  s390: avoid undefined behaviour
  s390/disassembler: generate opcode tables from text file
  s390/disassembler: remove insn_to_mnemonic()
  s390/dasd: avoid calling do_gettimeofday()
  s390: vfio-ccw: Do not attempt to free no-op, test and tic cda.
  s390: remove named saved segment support
  s390/archrandom: Reconsider s390 arch random implementation
  s390/pci: do not require AIS facility
  s390/qdio: sanitize put_indicator
  s390/qdio: use atomic_cmpxchg
  s390/nmi: avoid using long-displacement facility
  s390: pass endianness info to sparse
  s390/decompressor: remove informational messages
  ...