Commit Graph

797077 Commits

Author SHA1 Message Date
Christophe Leroy c62ce9ef97 powerpc: remove remaining bits from CONFIG_APUS
commit f21f49ea63 ("[POWERPC] Remove the dregs of APUS support from
arch/powerpc") removed CONFIG_APUS, but forgot to remove the logic
which adapts tophys() and tovirt() for it.

This patch removes the last stale pieces.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy 32c8c4c621 powerpc/xmon: fix dump_segments()
mfsrin() takes segment num from bits 31-28 (IBM bits 0-3).

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Clarify bit numbering]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy 0ed5b55884 powerpc/8xx: add exception frame marker
This patch adds STACK_FRAME_REGS_MARKER in the stack at exception entry
in order to see interrupts in call traces as below:

[    0.013964] Call Trace:
[    0.014014] [c0745db0] [c007a9d4] tick_periodic.constprop.5+0xd8/0x104 (unreliable)
[    0.014086] [c0745dc0] [c007aa20] tick_handle_periodic+0x20/0x9c
[    0.014181] [c0745de0] [c0009cd0] timer_interrupt+0xa0/0x264
[    0.014258] [c0745e10] [c000e484] ret_from_except+0x0/0x14
[    0.014390] --- interrupt: 901 at console_unlock.part.7+0x3f4/0x528
[    0.014390]     LR = console_unlock.part.7+0x3f0/0x528
[    0.014455] [c0745ee0] [c0050334] console_unlock.part.7+0x114/0x528 (unreliable)
[    0.014542] [c0745f30] [c00524e0] register_console+0x3d8/0x44c
[    0.014625] [c0745f60] [c0675aac] cpm_uart_console_init+0x18/0x2c
[    0.014709] [c0745f70] [c06614f4] console_init+0x114/0x1cc
[    0.014795] [c0745fb0] [c0658b68] start_kernel+0x300/0x3d8
[    0.014864] [c0745ff0] [c00022cc] start_here+0x44/0x98

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy e93ba1b7eb powerpc/book3s/32: fix number of bats in p/v_block_mapped()
This patch fixes the loop in p_block_mapped() and v_block_mapped()
to scan the entire bat_addrs[] array.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy 712877f874 powerpc/mm: Eliminate not possible mmu features at compile time
Depending on the CONFIG selected, many of the MMU features are
not possible. Lets only get the possible ones in MMU_FTRS_POSSIBLE.

This allows gcc to get rid at compile time of code related to
not possible features.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy 8a01960fb5 powerpc/smp: Use code patching to restore reset vector
Instead of hardcoding reset vector restore, use patch_instruction()

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy 6c16816b91 powerpc/44x: use patch_sites for TLB handlers patching
Use patch sites and associated helpers to manage TLB handlers
patching instead of hardcoding.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy d16952a629 powerpc/signal: Use code patching instead of hardcoding
Instead of hardcoding code modifications, use code patching functions.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy 002cdfc2c7 powerpc/8xx: use modify_instruction_site()
Instead of hardcoding the TLB handlers patching, use
the newly created modify_instruction_site() helper.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy 9efc74ff52 powerpc/book3s/32: Use patch_site to patch hash functions
Use patch_sites and the new modify_instruction_site() function
instead of hardcoding hash functions patching.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy 4a3a224c5a powerpc/book3s/32: Use MMU_FTR_HPTE_TABLE in head_32.S
Instead of manually patching a blr at hash_page() entry in
MMU_init_hw(), this patch adds a features section in head_32.S

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy 04b0a72f28 powerpc/32: use patch_site_addr() in machine_init()
Use patch_site_addr() instead of hardcoding the
address calculation in machine_init()

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy 36b08b431e powerpc: add modify_instruction() and modify_instruction_site()
Add two helpers to avoid hardcoding of instructions modifications.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy 45090c2661 powerpc: simplify patch_instruction_site() and patch_branch_site()
Using patch_site_addr() helper, patch_instruction_site() and
patch_branch_site() can be simplified and inlined.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy 584dbc7727 powerpc/mm: remove unused variable
In file included from ./include/linux/hugetlb.h:445:0,
                 from arch/powerpc/kernel/setup-common.c:37:
./arch/powerpc/include/asm/hugetlb.h: In function ‘huge_ptep_clear_flush’:
./arch/powerpc/include/asm/hugetlb.h:154:8: error: variable ‘pte’ set but not used [-Werror=unused-but-set-variable]

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:32 +11:00
Christophe Leroy 6bf752daca powerpc: implement CONFIG_DEBUG_VIRTUAL
This patch implements CONFIG_DEBUG_VIRTUAL to warn about
incorrect use of virt_to_phys() and page_to_phys()

Below is the result of test_debug_virtual:

[    1.438746] WARNING: CPU: 0 PID: 1 at ./arch/powerpc/include/asm/io.h:808 test_debug_virtual_init+0x3c/0xd4
[    1.448156] CPU: 0 PID: 1 Comm: swapper Not tainted 4.20.0-rc5-00560-g6bfb52e23a00-dirty #532
[    1.457259] NIP:  c066c550 LR: c0650ccc CTR: c066c514
[    1.462257] REGS: c900bdb0 TRAP: 0700   Not tainted  (4.20.0-rc5-00560-g6bfb52e23a00-dirty)
[    1.471184] MSR:  00029032 <EE,ME,IR,DR,RI>  CR: 48000422  XER: 20000000
[    1.477811]
[    1.477811] GPR00: c0650ccc c900be60 c60d0000 00000000 006000c0 c9000000 00009032 c7fa0020
[    1.477811] GPR08: 00002400 00000001 09000000 00000000 c07b5d04 00000000 c00037d8 00000000
[    1.477811] GPR16: 00000000 00000000 00000000 00000000 c0760000 c0740000 00000092 c0685bb0
[    1.477811] GPR24: c065042c c068a734 c0685b8c 00000006 00000000 c0760000 c075c3c0 ffffffff
[    1.512711] NIP [c066c550] test_debug_virtual_init+0x3c/0xd4
[    1.518315] LR [c0650ccc] do_one_initcall+0x8c/0x1cc
[    1.523163] Call Trace:
[    1.525595] [c900be60] [c0567340] 0xc0567340 (unreliable)
[    1.530954] [c900be90] [c0650ccc] do_one_initcall+0x8c/0x1cc
[    1.536551] [c900bef0] [c0651000] kernel_init_freeable+0x1f4/0x2cc
[    1.542658] [c900bf30] [c00037ec] kernel_init+0x14/0x110
[    1.547913] [c900bf40] [c000e1d0] ret_from_kernel_thread+0x14/0x1c
[    1.553971] Instruction dump:
[    1.556909] 3ca50100 bfa10024 54a5000e 3fa0c076 7c0802a6 3d454000 813dc204 554893be
[    1.564566] 7d294010 7d294910 90010034 39290001 <0f090000> 7c3e0b78 955e0008 3fe0c062
[    1.572425] ---[ end trace 6f6984225b280ad6 ]---
[    1.577467] PA: 0x09000000 for VA: 0xc9000000
[    1.581799] PA: 0x061e8f50 for VA: 0xc61e8f50

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-19 18:56:26 +11:00
Christophe Leroy 10fdf838e5 lib: fix build failure in CONFIG_DEBUG_VIRTUAL test
On several arches, virt_to_phys() is in io.h

Build fails without it:

  CC      lib/test_debug_virtual.o
lib/test_debug_virtual.c: In function 'test_debug_virtual_init':
lib/test_debug_virtual.c:26:7: error: implicit declaration of function 'virt_to_phys' [-Werror=implicit-function-declaration]
  pa = virt_to_phys(va);
       ^

Fixes: e4dace3615 ("lib: add test module for CONFIG_DEBUG_VIRTUAL")
CC: stable@vger.kernel.org
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-17 22:12:30 +11:00
Mathieu Malaterre ebd1d3b74f powerpc/32: Move the old 6xx -mcpu logic before the TARGET_CPU logic
The code:

  ifdef CONFIG_6xx
  KBUILD_CFLAGS          += -mcpu=powerpc
  endif

was added in 2006 in commit f48b8296b3 ("[PATCH] powerpc32: Set cpu
explicitly in kernel compiles"). This change was acceptable since the
TARGET_CPU logic was 64-bit only.

Since commit 0e00a8c9fd ("powerpc: Allow CPU selection
also on PPC32") this logic is no longer acceptable after the TARGET_CPU
specific. It currently appends -mcpu=powerpc at the end of the command
line, after any TARGET_CPU specific:

  gcc -Wp,-MD,init/.do_mounts.o.d ...
    -mcpu=powerpc -mbig-endian -m32 ...
    -mcpu=e300c2 ...
    -mcpu=powerpc ...
    ../init/do_mounts.c

Fixes: 0e00a8c9fd ("powerpc: Allow CPU selection also on PPC32")
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-17 22:12:30 +11:00
Michael Ellerman c7e900c05b powerpc/ipic: Remove unused ipic_set_priority()
ipic_set_priority() has been unused since 2006 when the last usage was
removed in commit b9f0f1bb2b ("[POWERPC] Adapt ipic driver to new
host_ops interface, add set_irq_type to set IRQ sense").

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-17 22:12:30 +11:00
Michael Ellerman 4d6a198273 Merge branch 'fixes' into next
Merge our fixes branch again, this has a couple of build fixes and also
a change to do_syscall_trace_enter() that will conflict with a patch we
want to apply in next.
2018-12-17 22:11:54 +11:00
Elvira Khabirova a225f15674 powerpc/ptrace: replace ptrace_report_syscall() with a tracehook call
Arch code should use tracehook_*() helpers, as documented in
include/linux/tracehook.h, ptrace_report_syscall() is not expected to
be used outside that file.

The patch does not look very nice, but at least it is correct
and opens the way for PTRACE_GET_SYSCALL_INFO API.

Co-authored-by: Dmitry V. Levin <ldv@altlinux.org>
Fixes: 5521eb4bca ("powerpc/ptrace: Add support for PTRACE_SYSEMU")
Signed-off-by: Elvira Khabirova <lineprinter@altlinux.org>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
[mpe: Take this as a minimal fix for 4.20, we'll rework it later]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-10 15:19:58 +11:00
Oliver O'Halloran 9ef34630a4 powerpc/mm: Fallback to RAM if the altmap is unusable
The "altmap" is used to provide a pool of memory that is reserved for
the vmemmap backing of hot-plugged memory. This is useful when adding
large amount of ZONE_DEVICE memory to a system with a limited amount of
normal memory.

On ppc64 we use huge pages to map the vmemmap which requires the backing
storage to be contigious and aligned to the hugepage size. The altmap
implementation allows for the altmap provider to reserve a few PFNs at
the start of the range for it's own uses and when this occurs the
first chunk of the altmap is not usable for hugepage mappings. On hash
there is no sane way to fall back to a normal sized page mapping so we
fail the allocation. This results in memory hotplug failing with
ENOMEM when the new range doesn't fall into an existing vmemmap block.

This patch handles this case by falling back to using system memory
rather than failing if we cannot allocate from the altmap. This
fallback should only ever be used for the first vmemmap block so it
should not cause excess memory consumption.

Fixes: 7b73d978a5 ("mm: pass the vmem_altmap to vmemmap_populate")
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-09 21:33:21 +11:00
Oliver O'Halloran 43001c52b6 powerpc/papr_scm: Use ibm,unit-guid as the iset cookie
The interleave set cookie is used to determine if a label stored in the
metadata space should be applied to the current region. This is
important in the case of NVDIMMs since the firmware may change the
interleaving configuration of a DIMM which would invalidate the existing
labels. In our case the hypervisor hides those details from us so we
don't really care, but libnvdimm still requires the interleave set
cookie to be non-zero.

For our purposes we just need the set cookie to be unique and fixed for
a given PAPR SCM region and using the unit-guid (really a UUID) is fine
for this purpose.

Fixes: b5beae5e22 ("powerpc/pseries: Add driver for PAPR SCM regions")
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
[mpe: Use kernel types (u64)]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-09 21:32:51 +11:00
Oliver O'Halloran b0d65a8cbc powerpc/papr_scm: Fix DIMM device registration race
When a new nvdimm device is registered with libnvdimm via
nvdimm_create() it is added as a device on the nvdimm bus. The probe
function for the DIMM driver is potentially quite slow so actually
registering and probing the device is done in an async domain rather
than immediately after device creation. This can result in a race where
the region device (created 2nd) is probed first and fails to activate at
boot.

To fix this we use the same approach as the ACPI/NFIT driver which is to
check that all the DIMM devices registered successfully. LibNVDIMM
provides the nvdimm_bus_count_dimms() function which synchronises with
the async domain and verifies that the dimm was successfully registered
with the bus.

If either of these does not occur then we bail.

Fixes: b5beae5e22 ("powerpc/pseries: Add driver for PAPR SCM regions")
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-09 21:32:30 +11:00
Oliver O'Halloran 409dd7dc83 powerpc/papr_scm: Remove endian conversions
The return values of a h-call are returned in the CPU registers and
written to the provided buffer by the plpar_hcall() wrapper. As a result
the values written to memory are always in the native endian and should
not be byte swapped.

The inital implementation of the H-Call interface was done in qemu and
the returned values were byte swapped unnecessarily in both the
hypervisor and in the driver so this was only noticed when bringing up
the PowerVM implementation.

Fixes: b5beae5e22 ("powerpc/pseries: Add driver for PAPR SCM regions")
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-09 21:32:30 +11:00
Oliver O'Halloran 683ec0e04a powerpc/papr_scm: Update DT properties
The ibm,unit-sizes property was originally specified as an array of two
u32s corresponding to the memory block size, and the number of blocks
available in that region. A fairly last-minute change to the SCM DT
specification was splitting that into two seperate u64 properties:
ibm,block-sizes and ibm,number-of-blocks that convey the same
information. No firmware / hypervisor that emitted the ibm,unit-size
property ever appeared in the wild.

Fixes: b5beae5e22 ("powerpc/pseries: Add driver for PAPR SCM regions")
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
[mpe: Use kernel types (u32/u64)]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-09 21:32:16 +11:00
Oliver O'Halloran 5961352611 powerpc/papr_scm: Fix resource end address
Fix an off-by-one error in the memory resource range. This resource is
used to determine the address range of the memory to be hot-plugged as
ZONE_DEVICE memory. The current end address results in the kernel
attempting to map an additional memblock and the hypervisor may reject
the mapping resulting in the entire hot-plug failing.

Fixes: b5beae5e22 ("powerpc/pseries: Add driver for PAPR SCM regions")
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-07 23:32:02 +11:00
Oliver O'Halloran 14ebfec071 powerpc/papr_scm: Use depend instead of select
Making PAPR_SCM select LIBNVDIMM results in circular dependencies in
Kconfig when another symbol depends on it. Fix this by replacing the
select with a depends.

Fixes: b5beae5e22 ("powerpc/pseries: Add driver for PAPR SCM regions")
Reported-by: Alastair D'Silva <alastair@d-silva.org>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-07 23:32:01 +11:00
Sandipan Das a6460b03f9 powerpc/bpf: Fix broken uapi for BPF_PROG_TYPE_PERF_EVENT
Now that there are different variants of pt_regs for userspace and
kernel, the uapi for the BPF_PROG_TYPE_PERF_EVENT program type must be
changed by exporting the user_pt_regs structure instead of the pt_regs
structure that is in-kernel only.

Fixes: 002af9391b ("powerpc: Split user/kernel definitions of struct pt_regs")
Signed-off-by: Sandipan Das <sandipan@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-07 23:19:04 +11:00
Michael Ellerman e41b93a6be powerpc/boot: Fix build failures with -j 1
In commit 5e9dcb6188 ("powerpc/boot: Expose Kconfig symbols to
wrapper") we added a dependency to serial.c on autoconf.h:

  $(obj)/serial.c: $(obj)/autoconf.h

This works when building in-tree (ie. with KBUILD_OUTPUT unset)
because the obj tree is the src tree.

But when building with eg. O=build and -j 1 the build fails:

  gcc ... -I../arch/powerpc/boot -c -o arch/powerpc/boot/serial.o arch/powerpc/boot/serial.c
  gcc: error: arch/powerpc/boot/serial.c: No such file or directory

Why this is only happening with -j 1 is not clear, when building with
-j greater than 1 somehow we decide to look for serial.c in the src
tree (../), eg:

  gcc -I../arch/powerpc/boot -c -o arch/powerpc/boot/serial.o ../arch/powerpc/boot/serial.c

Regardless we shouldn't be specifying a dependency on serial.c in the
build tree, we want to add a dependency to the version in $(srctree)
so fix the rule to say that.

Fixes: 5e9dcb6188 ("powerpc/boot: Expose Kconfig symbols to wrapper")
Tested-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-06 16:10:15 +11:00
Christophe Leroy 7c91efce16 powerpc/mm: dump block address translation on book3s/32
This patch adds a debugfs file to dump block address translation:

~# cat /sys/kernel/debug/powerpc/block_address_translation
---[ Instruction Block Address Translations ]---
0:         -
1:         -
2: 0xc0000000-0xcfffffff 0x00000000 Kernel EXEC coherent
3: 0xd0000000-0xdfffffff 0x10000000 Kernel EXEC coherent
4:         -
5:         -
6:         -
7:         -

---[ Data Block Address Translations ]---
0:         -
1:         -
2: 0xc0000000-0xcfffffff 0x00000000 Kernel RW coherent
3: 0xd0000000-0xdfffffff 0x10000000 Kernel RW coherent
4:         -
5:         -
6:         -
7:         -

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:46:49 +11:00
Christophe Leroy 0261a508c9 powerpc/mm: dump segment registers on book3s/32
This patch creates a debugfs file to see content of
segment registers

  # cat /sys/kernel/debug/segment_registers
  ---[ User Segments ]---
  0x00000000-0x0fffffff Kern key 1 User key 1 VSID 0xade2b0
  0x10000000-0x1fffffff Kern key 1 User key 1 VSID 0xade3c1
  0x20000000-0x2fffffff Kern key 1 User key 1 VSID 0xade4d2
  0x30000000-0x3fffffff Kern key 1 User key 1 VSID 0xade5e3
  0x40000000-0x4fffffff Kern key 1 User key 1 VSID 0xade6f4
  0x50000000-0x5fffffff Kern key 1 User key 1 VSID 0xade805
  0x60000000-0x6fffffff Kern key 1 User key 1 VSID 0xade916
  0x70000000-0x7fffffff Kern key 1 User key 1 VSID 0xadea27
  0x80000000-0x8fffffff Kern key 1 User key 1 VSID 0xadeb38
  0x90000000-0x9fffffff Kern key 1 User key 1 VSID 0xadec49
  0xa0000000-0xafffffff Kern key 1 User key 1 VSID 0xaded5a
  0xb0000000-0xbfffffff Kern key 1 User key 1 VSID 0xadee6b

  ---[ Kernel Segments ]---
  0xc0000000-0xcfffffff Kern key 0 User key 1 VSID 0x000ccc
  0xd0000000-0xdfffffff Kern key 0 User key 1 VSID 0x000ddd
  0xe0000000-0xefffffff Kern key 0 User key 1 VSID 0x000eee
  0xf0000000-0xffffffff Kern key 0 User key 1 VSID 0x000fff

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
[mpe: Move it under /sys/kernel/debug/powerpc, make sr_init() __init]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:54 +11:00
Joel Stanley b682c86924 powerpc/math-emu: Update macros from GCC
The add_ssaaaa, sub_ddmmss, umul_ppmm and udiv_qrnnd macros originate
from GCC's longlong.h which in turn was copied from GMP's longlong.h a
few decades ago.

This was found when compiling with clang:

   arch/powerpc/math-emu/fnmsub.c:46:2: error: invalid use of a cast in a
   inline asm context requiring an l-value: remove the cast or build with
   -fheinous-gnu-extensions
           FP_ADD_D(R, T, B);
           ^~~~~~~~~~~~~~~~~
   ...

   ./arch/powerpc/include/asm/sfp-machine.h:283:27: note: expanded from
   macro 'sub_ddmmss'
                  : "=r" ((USItype)(sh)),                                  \
                          ~~~~~~~~~~^~~

Segher points out: this was fixed in GCC over 16 years ago
( https://gcc.gnu.org/r56600 ), and in GMP (where it comes from)
presumably before that.

Update the add_ssaaaa, sub_ddmmss, umul_ppmm and udiv_qrnnd macros to
the latest GCC version in order to git rid of the invalid casts. These
were taken as-is from GCC's longlong in order to make future syncs
obvious. Other parts of sfp-machine.h were left as-is as the file
contains more features than present in longlong.h.

Link: https://github.com/ClangBuiltLinux/linux/issues/260
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Russell Currey afa202b6bd powerpc/tools/checkpatch: Ignore DT_SPLIT_BINDING_PATCH
From what I've seen, every time this warning comes up it's bogus,
so let's ignore it.

Signed-off-by: Russell Currey <ruscur@russell.cc>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy b14fc50266 powerpc/8xx: regroup TLB handler routines
As this is running with MMU off, the CPU only does speculative
fetch for code in the same page.

Following the significant size reduction of TLB handler routines,
the side handlers can be brought back close to the main part,
ie in the same page.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy 74fabcadfd powerpc/8xx: don't use r12/SPRN_SPRG_SCRATCH2 in TLB Miss handlers
This patch reworks the TLB Miss handler in order to not use r12
register, hence avoiding having to save it into SPRN_SPRG_SCRATCH2.

In the DAR Fixup code we can now use SPRN_M_TW, freeing
SPRN_SPRG_SCRATCH2.

Then SPRN_SPRG_SCRATCH2 may be used for something else in the future.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy 55c8fc3f49 powerpc/8xx: reintroduce 16K pages with HW assistance
Using this HW assistance implies some constraints on the
page table structure:
- Regardless of the main page size used (4k or 16k), the
level 1 table (PGD) contains 1024 entries and each PGD entry covers
a 4Mbytes area which is managed by a level 2 table (PTE) containing
also 1024 entries each describing a 4k page.
- 16k pages require 4 identifical entries in the L2 table
- 512k pages PTE have to be spread every 128 bytes in the L2 table
- 8M pages PTE are at the address pointed by the L1 entry and each
8M page require 2 identical entries in the PGD.

In order to use hardware assistance with 16K pages, this patch does
the following modifications:
- Make PGD size independent of the main page size
- In 16k pages mode, redefine pte_t as a struct with 4 elements,
and populate those 4 elements in __set_pte_at() and pte_update()
- Adapt the size of the hugepage tables.
- Define a PTE_FRAGMENT_NB so that a 16k page contains 4 page tables.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy 3fb69c6a1a powerpc/8xx: Enable 512k hugepage support with HW assistance
For using 512k pages with hardware assistance, the PTEs have to be spread
every 128 bytes in the L2 table.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy 22569b881d powerpc/8xx: Enable 8M hugepage support with HW assistance
HW assistance naturally supports 8M huge pages without
further modifications.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy 6a8f911b50 powerpc/8xx: Use hardware assistance in TLB handlers
Today, on the 8xx the TLB handlers do SW tablewalk by doing all
the calculation in ASM, in order to match with the Linux page
table structure.

The 8xx offers hardware assistance which allows significant size
reduction of the TLB handlers, hence also reduces the time spent
in the handlers.

However, using this HW assistance implies some constraints on the
page table structure:
- Regardless of the main page size used (4k or 16k), the
level 1 table (PGD) contains 1024 entries and each PGD entry covers
a 4Mbytes area which is managed by a level 2 table (PTE) containing
also 1024 entries each describing a 4k page.
- 16k pages require 4 identifical entries in the L2 table
- 512k pages PTE have to be spread every 128 bytes in the L2 table
- 8M pages PTE are at the address pointed by the L1 entry and each
8M page require 2 identical entries in the PGD.

This patch modifies the TLB handlers to use HW assistance for 4K PAGES.

Before that patch, the mean time spent in TLB miss handlers is:
- ITLB miss: 80 ticks
- DTLB miss: 62 ticks
After that patch, the mean time spent in TLB miss handlers is:
- ITLB miss: 72 ticks
- DTLB miss: 54 ticks
So the improvement is 10% for ITLB and 13% for DTLB misses

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy 5af543be14 powerpc/8xx: Temporarily disable 16k pages and hugepages
In preparation of making use of hardware assistance in TLB handlers,
this patch temporarily disables 16K pages and hugepages. The reason
is that when using HW assistance in 4K pages mode, the linux model
fit with the HW model for 4K pages and 8M pages.

However for 16K pages and 512K mode some additional work is needed
to get linux model fit with HW model.
For the 8M pages, they will naturaly come back when we switch to
HW assistance, without any additional handling.
In order to keep the following patch smaller, the removal of the
current special handling for 8M pages gets removed here as well.

Therefore the 4K pages mode will be implemented first and without
support for 512k hugepages. Then the 512k hugepages will be brought
back. And the 16K pages will be implemented in the following step.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy 8cfe4f5242 powerpc/8xx: Move SW perf counters in first 32kb of memory
In order to simplify time critical exceptions handling 8xx
specific SW perf counters, this patch moves the counters into
the beginning of memory. This is possible because .text is readable
and the counters are never modified outside of the handlers.

By doing this, we avoid having to set a second register with
the upper part of the address of the counters.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy 32bff4b905 powerpc/mm: remove unnecessary test in pgtable_cache_init()
pgtable_cache_add() gracefully handles the case when a cache that
size already exists by returning early with the following test:

	if (PGT_CACHE(shift))
		return; /* Already have a cache of this size */

It is then not needed to test the existence of the cache before.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy 1e03c7e2ea powerpc/mm: fix a warning when a cache is common to PGD and hugepages
While implementing TLB miss HW assistance on the 8xx, the following
warning was encountered:

[  423.732965] WARNING: CPU: 0 PID: 345 at mm/slub.c:2412 ___slab_alloc.constprop.30+0x26c/0x46c
[  423.733033] CPU: 0 PID: 345 Comm: mmap Not tainted 4.18.0-rc8-00664-g2dfff9121c55 #671
[  423.733075] NIP:  c0108f90 LR: c0109ad0 CTR: 00000004
[  423.733121] REGS: c455bba0 TRAP: 0700   Not tainted  (4.18.0-rc8-00664-g2dfff9121c55)
[  423.733147] MSR:  00021032 <ME,IR,DR,RI>  CR: 24224848  XER: 20000000
[  423.733319]
[  423.733319] GPR00: c0109ad0 c455bc50 c4521910 c60053c0 007080c0 c0011b34 c7fa41e0 c455be30
[  423.733319] GPR08: 00000001 c00103a0 c7fa41e0 c49afcc4 24282842 10018840 c079b37c 00000040
[  423.733319] GPR16: 73f00000 00210d00 00000000 00000001 c455a000 00000100 00000200 c455a000
[  423.733319] GPR24: c60053c0 c0011b34 007080c0 c455a000 c455a000 c7fa41e0 00000000 00009032
[  423.734190] NIP [c0108f90] ___slab_alloc.constprop.30+0x26c/0x46c
[  423.734257] LR [c0109ad0] kmem_cache_alloc+0x210/0x23c
[  423.734283] Call Trace:
[  423.734326] [c455bc50] [00000100] 0x100 (unreliable)
[  423.734430] [c455bcc0] [c0109ad0] kmem_cache_alloc+0x210/0x23c
[  423.734543] [c455bcf0] [c0011b34] huge_pte_alloc+0xc0/0x1dc
[  423.734633] [c455bd20] [c01044dc] hugetlb_fault+0x408/0x48c
[  423.734720] [c455bdb0] [c0104b20] follow_hugetlb_page+0x14c/0x44c
[  423.734826] [c455be10] [c00e8e54] __get_user_pages+0x1c4/0x3dc
[  423.734919] [c455be80] [c00e9924] __mm_populate+0xac/0x140
[  423.735020] [c455bec0] [c00db14c] vm_mmap_pgoff+0xb4/0xb8
[  423.735127] [c455bf00] [c00f27c0] ksys_mmap_pgoff+0xcc/0x1fc
[  423.735222] [c455bf40] [c000e0f8] ret_from_syscall+0x0/0x38
[  423.735271] Instruction dump:
[  423.735321] 7cbf482e 38fd0008 7fa6eb78 7fc4f378 4bfff5dd 7fe3fb78 4bfffe24 81370010
[  423.735536] 71280004 41a2ff88 4840c571 4bffff80 <0fe00000> 4bfffeb8 81340010 712a0004
[  423.735757] ---[ end trace e9b222919a470790 ]---

This warning occurs when calling kmem_cache_zalloc() on a
cache having a constructor.

In this case it happens because PGD cache and 512k hugepte cache are
the same size (4k). While a cache with constructor is created for
the PGD, hugepages create cache without constructor and uses
kmem_cache_zalloc(). As both expect a cache with the same size,
the hugepages reuse the cache created for PGD, hence the conflict.

In order to avoid this conflict, this patch:
- modifies pgtable_cache_add() so that a zeroising constructor is
added for any cache size.
- replaces calls to kmem_cache_zalloc() by kmem_cache_alloc()

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy 0356656284 powerpc/mm: replace hugetlb_cache by PGT_CACHE(PTE_T_ORDER)
Instead of opencoding cache handling for the special case
of hugepage tables having a single pte_t element, this
patch makes use of the common pgtable_cache helpers

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy 129dd323dd powerpc/mm: enable the use of page table cache of order 0
hugepages uses a cache of order 0. Lets allow page tables
of order 0 in the common part in order to avoid open coding
in hugetlb

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy 32ea4c1499 powerpc/mm: Extend pte_fragment functionality to PPC32
In order to allow the 8xx to handle pte_fragments, this patch
extends the use of pte_fragments to PPC32 platforms.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy a74791dd98 powerpc/mm: add helpers to get/set mm.context->pte_frag
In order to handle pte_fragment functions with single fragment
without adding pte_frag in all mm_context_t, this patch creates
two helpers which do nothing on platforms using a single fragment.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy d09780f3a8 powerpc/mm: Move pgtable_t into platform headers
This patch move pgtable_t into platform headers.

It gets rid of the CONFIG_PPC_64K_PAGES case for PPC64
as nohash/64 doesn't support CONFIG_PPC_64K_PAGES.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00
Christophe Leroy 994da93d19 powerpc/mm: move platform specific mmu-xxx.h in platform directories
The purpose of this patch is to move platform specific
mmu-xxx.h files in platform directories like pte-xxx.h files.

In the meantime this patch creates common nohash and
nohash/32 + nohash/64 mmu.h files for future common parts.

Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-12-04 19:45:01 +11:00