powerpc/rtas: arch-wide function token lookup conversions

With the tokens for all implemented RTAS functions now available via
rtas_function_token(), which is optimal and safe for arbitrary
contexts, there is no need to use rtas_token() or cache its result.

Most conversions are trivial, but a few are worth describing in more
detail:

* Error injection token comparisons for lockdown purposes are
consolidated into a simple predicate: token_is_restricted_errinjct().

* A couple of special cases in block_rtas_call() do not use
rtas_token() but perform string comparisons against names in the
function table. These are converted to compare against token values
instead, which is logically equivalent but less expensive.

* The lookup for the ibm,os-term token can be deferred until needed,
instead of caching it at boot to avoid device tree traversal during
panic.

* Since rtas_function_token() accesses a read-only data structure
without taking any locks, xmon's lookup of set-indicator can be
performed as needed instead of cached at startup.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230125-b4-powerpc-rtas-queue-v3-20-26929c8cce78@linux.ibm.com

powerpc/rtasd: use correct OF API for event scan rate

rtas_token() should be used only for properties that are RTAS function
tokens. "rtas-event-scan-rate" does not contain a function token, but it
has the same size/format as token properties so reading it with
rtas_token() happens to work.

Convert to of_property_read_u32().

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Andrew Donnellan <ajd@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221118150751.469393-3-nathanl@linux.ibm.com

powerpc: Remove asm/prom.h from all files that don't need it

Several files include asm/prom.h for no reason.

Clean it up.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
[mpe: Drop change to prom_parse.c as reported by lkp@intel.com]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7c9b8fda63dcf63e1b28f43e7ebdb95182cbc286.1646767214.git.christophe.leroy@csgroup.eu

powerpc/kernel: Add __init attribute to eligible functions

Some functions defined in `arch/powerpc/kernel` (and one in `arch/powerpc/
kexec`) are deserving of an `__init` macro attribute. These functions are
only called by other initialization functions and therefore should inherit
the attribute.
Also, change function declarations in header files to include `__init`.

Signed-off-by: Nick Child <nick.child@ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211216220035.605465-2-nick.child@ibm.com

powerpc: Replace deprecated CPU-hotplug functions.

The functions get_online_cpus() and put_online_cpus() have been
deprecated during the CPU hotplug rework. They map directly to
cpus_read_lock() and cpus_read_unlock().

Replace deprecated CPU-hotplug functions with the official version.
The behavior remains unchanged.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210803141621.780504-4-bigeasy@linutronix.de

powerpc/rtasd: simplify handle_rtas_event(), emit message on events

prrn_is_enabled() always returns false/0, so handle_rtas_event() can
be simplified and some dead code can be removed. Use machine_is()
instead of #ifdef to run this code only on pseries, and add an
informational ratelimited message that we are ignoring the
events. PRRN events are relatively rare in normal operation and
usually arise from operator-initiated actions such as a DPO (Dynamic
Platform Optimizer) run.

Eventually we do want to consume these events and update the device
tree, but that needs more care to be safe vs LPM and DLPAR.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200612051238.1007764-13-nathanl@linux.ibm.com

proc: convert everything to "struct proc_ops"

The most notable change is DEFINE_SHOW_ATTRIBUTE macro split in
seq_file.h.

Conversion rule is:

llseek => proc_lseek
unlocked_ioctl => proc_ioctl

xxx => proc_xxx

delete ".owner = THIS_MODULE" line

[akpm@linux-foundation.org: fix drivers/isdn/capi/kcapi_proc.c]
[sfr@canb.auug.org.au: fix kernel/sched/psi.c]
Link: http://lkml.kernel.org/r/20200122180545.36222f50@canb.auug.org.au
Link: http://lkml.kernel.org/r/20191225172546.GB13378@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Remove 'type' argument from access_ok() function

Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.

It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.

A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.

This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.

There were a couple of notable cases:

- csky still had the old "verify_area()" name as an alias.

- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)

- microblaze used the type argument for a debug printout

but other than those oddities this should be a total no-op patch.

I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

powerpc/pseries: PAPR persistent memory support

This patch implements support for discovering storage class memory
devices at boot and for handling hotplug of new regions via RTAS
hotplug events.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
[mpe: Fix CONFIG_MEMORY_HOTPLUG=n build]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/rtasd: Improve unknown error logging

Currently when we get an unknown RTAS event it prints the type as
"Unknown" and no other useful information. Add the raw type code to the
log message so that we have something to work off.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Reviewed-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/pseries: Remove prrn_work workqueue

When a PRRN event is received we are already running in a worker
thread. Instead of spawning off another worker thread on the prrn_work
workqueue to handle the PRRN event we can just call the PRRN handler
routine directly.

With this update we can also pass the scope variable for the PRRN
event directly to the handler instead of it being a global variable.

This patch fixes the following oops mnessage we are seeing in PRRN testing:

Oops: Bad kernel stack pointer, sig: 6 [#1]
SMP NR_CPUS=2048 NUMA pSeries
Modules linked in: nfsv3 nfs_acl rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace sunrpc fscache binfmt_misc reiserfs vfat fat rpadlpar_io(X) rpaphp(X) tcp_diag udp_diag inet_diag unix_diag af_packet_diag netlink_diag af_packet xfs libcrc32c dm_service_time ibmveth(X) ses enclosure scsi_transport_sas rtc_generic btrfs xor raid6_pq sd_mod ibmvscsi(X) scsi_transport_srp ipr(X) libata sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_dh_alua scsi_mod autofs4
Supported: Yes, External 54
CPU: 7 PID: 18967 Comm: kworker/u96:0 Tainted: G X 4.4.126-94.22-default #1
Workqueue: pseries hotplug workque pseries_hp_work_fn
task: c000000775367790 ti: c00000001ebd4000 task.ti: c00000070d140000
NIP: 0000000000000000 LR: 000000001fb3d050 CTR: 0000000000000000
REGS: c00000001ebd7d40 TRAP: 0700 Tainted: G X (4.4.126-94.22-default)
MSR: 8000000102081000 <41,VEC,ME5 CR: 28000002 XER: 20040018 4
CFAR: 000000001fb3d084 40 419 1 3
GPR00: 000000000000000040000000000010007 000000001ffff400 000000041fffe200
GPR04: 000000000000008050000000000000000 000000001fb15fa8 0000000500000500
GPR08: 000000000001f40040000000000000001 0000000000000000 000005:5200040002
GPR12: 00000000000000005c000000007a05400 c0000000000e89f8 000000001ed9f668
GPR16: 000000001fbeff944000000001fbeff94 000000001fb545e4 0000006000000060
GPR20: ffffffffffffffff4ffffffffffffffff 0000000000000000 0000000000000000
GPR24: 00000000000000005400000001fb3c000 0000000000000000 000000001fb1b040
GPR28: 000000001fb240004000000001fb440d8 0000000000000008 0000000000000000
NIP [0000000000000000] 5 (null)
LR [000000001fb3d050] 031fb3d050
Call Trace: 4
Instruction dump: 4 5:47 12 2
XXXXXXXX XXXXXXXX XXXXX4XX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX
XXXXXXXX XXXXXXXX XXXXX5XX XXXXXXXX 60000000 60000000 60000000 60000000
---[ end trace aa5627b04a7d9d6b ]--- 3NMI watchdog: BUG: soft lockup - CPU#27 stuck for 23s! [kworker/27:0:13903]
Modules linked in: nfsv3 nfs_acl rpcsec_gss_krb5 auth_rpcgss nfsv4 dns_resolver nfs lockd grace sunrpc fscache binfmt_misc reiserfs vfat fat rpadlpar_io(X) rpaphp(X) tcp_diag udp_diag inet_diag unix_diag af_packet_diag netlink_diag af_packet xfs libcrc32c dm_service_time ibmveth(X) ses enclosure scsi_transport_sas rtc_generic btrfs xor raid6_pq sd_mod ibmvscsi(X) scsi_transport_srp ipr(X) libata sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_dh_alua scsi_mod autofs4
Supported: Yes, External
CPU: 27 PID: 13903 Comm: kworker/27:0 Tainted: G D X 4.4.126-94.22-default #1
Workqueue: events prrn_work_fn
task: c000000747cfa390 ti: c00000074712c000 task.ti: c00000074712c000
NIP: c0000000008002a8 LR: c000000000090770 CTR: 000000000032e088
REGS: c00000074712f7b0 TRAP: 0901 Tainted: G D X (4.4.126-94.22-default)
MSR: 8000000100009033 <SF,EE,ME,IR,DR,RI,LE> CR: 22482044 XER: 20040000
CFAR: c0000000008002c4 SOFTE: 1
GPR00: c000000000090770 c00000074712fa30 c000000000f09800 c000000000fa1928 6:02
GPR04: c000000775f5e000 fffffffffffffffe 0000000000000001 c000000000f42db8
GPR08: 0000000000000001 0000000080000007 0000000000000000 0000000000000000
GPR12: 8006210083180000 c000000007a14400
NIP [c0000000008002a8] _raw_spin_lock+0x68/0xd0
LR [c000000000090770] mobility_rtas_call+0x50/0x100
Call Trace: 59 5
[c00000074712fa60] [c000000000090770] mobility_rtas_call+0x50/0x100
[c00000074712faf0] [c000000000090b08] pseries_devicetree_update+0xf8/0x530
[c00000074712fc20] [c000000000031ba4] prrn_work_fn+0x34/0x50
[c00000074712fc40] [c0000000000e0390] process_one_work+0x1a0/0x4e0
[c00000074712fcd0] [c0000000000e0870] worker_thread+0x1a0/0x6105:57 2
[c00000074712fd80] [c0000000000e8b18] kthread+0x128/0x150
[c00000074712fe30] [c0000000000096f8] ret_from_kernel_thread+0x5c/0x64
Instruction dump:
2c090000 40c20010 7d40192d 40c2fff0 7c2004ac 2fa90000 40de0018 5:540030 3
e8010010 ebe1fff8 7c0803a6 4e800020 <7c210b78> e92d0000 89290009 792affe3

Signed-off-by: John Allen <jallen@linux.ibm.com>
Signed-off-by: Haren Myneni <haren@us.ibm.com>
Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

treewide: Use array_size() in vmalloc()

The vmalloc() function has no 2-factor argument form, so multiplication
factors need to be wrapped in array_size(). This patch replaces cases of:

vmalloc(a * b)

with:
vmalloc(array_size(a, b))

as well as handling cases of:

vmalloc(a * b * c)

with:

vmalloc(array3_size(a, b, c))

This does, however, attempt to ignore constant size factors like:

vmalloc(4 * 1024)

though any constants defined via macros get caught up in the conversion.

Any factors with a sizeof() of "unsigned char", "char", and "u8" were
dropped, since they're redundant.

The Coccinelle script used for this was:

// Fix redundant parens around sizeof().
@@
type TYPE;
expression THING, E;
@@

(
vmalloc(
- (sizeof(TYPE)) * E
+ sizeof(TYPE) * E
, ...)
|
vmalloc(
- (sizeof(THING)) * E
+ sizeof(THING) * E
, ...)
)

// Drop single-byte sizes and redundant parens.
@@
expression COUNT;
typedef u8;
typedef __u8;
@@

(
vmalloc(
- sizeof(u8) * (COUNT)
+ COUNT
, ...)
|
vmalloc(
- sizeof(__u8) * (COUNT)
+ COUNT
, ...)
|
vmalloc(
- sizeof(char) * (COUNT)
+ COUNT
, ...)
|
vmalloc(
- sizeof(unsigned char) * (COUNT)
+ COUNT
, ...)
|
vmalloc(
- sizeof(u8) * COUNT
+ COUNT
, ...)
|
vmalloc(
- sizeof(__u8) * COUNT
+ COUNT
, ...)
|
vmalloc(
- sizeof(char) * COUNT
+ COUNT
, ...)
|
vmalloc(
- sizeof(unsigned char) * COUNT
+ COUNT
, ...)
)

// 2-factor product with sizeof(type/expression) and identifier or constant.
@@
type TYPE;
expression THING;
identifier COUNT_ID;
constant COUNT_CONST;
@@

(
vmalloc(
- sizeof(TYPE) * (COUNT_ID)
+ array_size(COUNT_ID, sizeof(TYPE))
, ...)
|
vmalloc(
- sizeof(TYPE) * COUNT_ID
+ array_size(COUNT_ID, sizeof(TYPE))
, ...)
|
vmalloc(
- sizeof(TYPE) * (COUNT_CONST)
+ array_size(COUNT_CONST, sizeof(TYPE))
, ...)
|
vmalloc(
- sizeof(TYPE) * COUNT_CONST
+ array_size(COUNT_CONST, sizeof(TYPE))
, ...)
|
vmalloc(
- sizeof(THING) * (COUNT_ID)
+ array_size(COUNT_ID, sizeof(THING))
, ...)
|
vmalloc(
- sizeof(THING) * COUNT_ID
+ array_size(COUNT_ID, sizeof(THING))
, ...)
|
vmalloc(
- sizeof(THING) * (COUNT_CONST)
+ array_size(COUNT_CONST, sizeof(THING))
, ...)
|
vmalloc(
- sizeof(THING) * COUNT_CONST
+ array_size(COUNT_CONST, sizeof(THING))
, ...)
)

// 2-factor product, only identifiers.
@@
identifier SIZE, COUNT;
@@

vmalloc(
- SIZE * COUNT
+ array_size(COUNT, SIZE)
, ...)

// 3-factor product with 1 sizeof(type) or sizeof(expression), with
// redundant parens removed.
@@
expression THING;
identifier STRIDE, COUNT;
type TYPE;
@@

(
vmalloc(
- sizeof(TYPE) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
vmalloc(
- sizeof(TYPE) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
vmalloc(
- sizeof(TYPE) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
vmalloc(
- sizeof(TYPE) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(TYPE))
, ...)
|
vmalloc(
- sizeof(THING) * (COUNT) * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
vmalloc(
- sizeof(THING) * (COUNT) * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
vmalloc(
- sizeof(THING) * COUNT * (STRIDE)
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
|
vmalloc(
- sizeof(THING) * COUNT * STRIDE
+ array3_size(COUNT, STRIDE, sizeof(THING))
, ...)
)

// 3-factor product with 2 sizeof(variable), with redundant parens removed.
@@
expression THING1, THING2;
identifier COUNT;
type TYPE1, TYPE2;
@@

(
vmalloc(
- sizeof(TYPE1) * sizeof(TYPE2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
vmalloc(
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2))
, ...)
|
vmalloc(
- sizeof(THING1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
vmalloc(
- sizeof(THING1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(THING1), sizeof(THING2))
, ...)
|
vmalloc(
- sizeof(TYPE1) * sizeof(THING2) * COUNT
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
|
vmalloc(
- sizeof(TYPE1) * sizeof(THING2) * (COUNT)
+ array3_size(COUNT, sizeof(TYPE1), sizeof(THING2))
, ...)
)

// 3-factor product, only identifiers, with redundant parens removed.
@@
identifier STRIDE, SIZE, COUNT;
@@

(
vmalloc(
- (COUNT) * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vmalloc(
- COUNT * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vmalloc(
- COUNT * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vmalloc(
- (COUNT) * (STRIDE) * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vmalloc(
- COUNT * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vmalloc(
- (COUNT) * STRIDE * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vmalloc(
- (COUNT) * (STRIDE) * (SIZE)
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
|
vmalloc(
- COUNT * STRIDE * SIZE
+ array3_size(COUNT, STRIDE, SIZE)
, ...)
)

// Any remaining multi-factor products, first at least 3-factor products
// when they're not all constants...
@@
expression E1, E2, E3;
constant C1, C2, C3;
@@

(
vmalloc(C1 * C2 * C3, ...)
|
vmalloc(
- E1 * E2 * E3
+ array3_size(E1, E2, E3)
, ...)
)

// And then all remaining 2 factors products when they're not all constants.
@@
expression E1, E2;
constant C1, C2;
@@

(
vmalloc(C1 * C2, ...)
|
vmalloc(
- E1 * E2
+ array_size(E1, E2)
, ...)
)

Signed-off-by: Kees Cook <keescook@chromium.org>

vfs: do bulk POLL* -> EPOLL* replacement

This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do. But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.

Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

powerpc: Use octal numbers for file permissions

Symbolic macros are unintuitive and hard to read, whereas octal constants
are much easier to interpret. Replace macros for the basic permission
flags (user/group/other read/write/execute) with numeric constants
instead, across the whole powerpc tree.

Introducing a significant number of changes across the tree for no runtime
benefit isn't exactly desirable, but so long as these macros are still
used in the tree people will keep sending patches that add them. Not only
are they hard to parse at a glance, there are multiple ways of coming to
the same value (as you can see with 0444 and 0644 in this patch) which
hurts readability.

Signed-off-by: Russell Currey <ruscur@russell.cc>
Reviewed-by: Cyril Bur <cyrilbur@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

ppc: annotate ->poll() instances

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

powerpc: Only obtain cpu_hotplug_lock if called by rtasd

Calling arch_update_cpu_topology from a CPU hotplug state machine callback
hits a deadlock because the function tries to get a read lock on
cpu_hotplug_lock while the state machine still holds a write lock on it.

Since all callers of arch_update_cpu_topology except rtasd already hold
cpu_hotplug_lock, this patch changes the function to use
stop_machine_cpuslocked and creates a separate function for rtasd which
still tries to obtain the lock.

Michael Bringmann investigated the bug and provided a detailed analysis
of the deadlock on this previous RFC for an alternate solution:

Signed-off-by: Thiago Jung Bauermann <bauerman@linux.vnet.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: John Allen <jallen@linux.vnet.ibm.com>
Cc: Michael Bringmann <mwb@linux.vnet.ibm.com>
Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1497996510-4032-1-git-send-email-bauerman@linux.vnet.ibm.com
Link: https://patchwork.ozlabs.org/patch/771293/

powerpc/pseries: Update affinity for memory and cpus specified in a PRRN event

Extend the existing PRRN infrastructure to perform the actual affinity
updating for cpus and memory in addition to the device tree updating.
For cpus, dynamic affinity updating already appears to exist in the
kernel in the form of arch_update_cpu_topology(). For memory, we must
place a READD operation on the hotplug queue for any phandle included in
the PRRN event that is determined to be an LMB.

Signed-off-by: John Allen <jallen@linux.vnet.ibm.com>
Reviewed-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Replace <asm/uaccess.h> with <linux/uaccess.h> globally

This was entirely automated, using the script by Al:

PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)

to do the replacement at the end of the merge window.

Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

powerpc/pseries: start rtasd before PCI probing

A strange behaviour is observed when comparing PCI hotplug in QEMU, between
x86 and pseries. If you consider the following steps:
- start a VM
- add a PCI device via the QEMU monitor before the rtasd has started (for
example starting the VM in paused state, or hotplug during FW or boot
loader)
- resume the VM execution

The x86 kernel detects the PCI device, but the pseries one does not.

This happens because the rtasd kernel worker is currently started under
device_initcall, while PCI probing happens earlier under subsys_initcall.

As a consequence, if we have a pending RTAS event at boot time, a message
is printed and the event is dropped.

This patch moves all the initialization of rtasd to arch_initcall, which is
run before subsys_call: this way, logging_enabled is true when the RTAS
event pops up and it is not lost anymore.

The proc fs bits stay at device_initcall because they cannot be run before
fs_initcall.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/pseries: Fix trivial typo in function name

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc: sparse: static-ify some things

As sparse suggests, these should be made static.

Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com>
Reviewed-by: Stewart Smith <stewart@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

param: convert some "on"/"off" users to strtobool

This changes several users of manual "on"/"off" parsing to use
strtobool.

Some side-effects:
- these uses will now parse y/n/1/0 meaningfully too
- the early_param uses will now bubble up parse errors

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Amitkumar Karwar <akarwar@marvell.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Joe Perches <joe@perches.com>
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nishant Sarmukadam <nishants@marvell.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Steve French <sfrench@samba.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

powerpc: Make a bunch of things static

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

powerpc/le: Enable RTAS events support

The current kernel code assumes big endian and parses RTAS events all
wrong. The most visible effect is that we cannot honor EPOW events,
meaning, for example, we cannot shut down a guest properly from the
hypervisor.

This new patch is largely inspired by Nathan's work: we get rid of all
the bit fields in the RTAS event structures (even the unused ones, for
consistency). We also introduce endian safe accessors for the fields used
by the kernel (trivial rtas_error_type() accessor added for consistency).

Cc: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc/pseries: Add /proc interface to control topology updates

There are instances in which we do not want topology updates to occur.
In order to allow this a /proc interface (/proc/powerpc/topology_updates)
is introduced so that topology updates can be enabled and disabled.

This patch also adds a prrn_is_enabled() call so that PRRN events are
handled in the kernel only if topology updating is enabled.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc/pseries: Add PRRN RTAS event handler

A PRRN event is signaled via the RTAS event-scan mechanism, which
returns a Hot Plug Event message "fixed part" indicating "Platform
Resource Reassignment". In response to the Hot Plug Event message,
we must call ibm,update-nodes to determine which resources were
reassigned and then ibm,update-properties to obtain the new affinity
information about those resources.

The PRRN event-scan RTAS message contains only the "fixed part" with
the "Type" field set to the value 160 and no Extended Event Log. The
four-byte Extended Event Log Length field is re-purposed (since no
Extended Event Log message is included) to pass the "scope" parameter
that causes the ibm,update-nodes to return the nodes affected by the
specific resource reassignment.

This patch adds a handler for RTAS events. The function
pseries_devicetree_update() (from mobility.c) is used to make the
ibm,update-nodes/ibm,update-properties RTAS calls. Updating the NUMA maps
(handled by a subsequent patch) will require significant processing,
so pseries_devicetree_update() is called from an asynchronous workqueue
to allow event processing to continue.

PRRN RTAS events on pseries systems are rare events that have to be
initiated from the HMC console for the system by an IBM tech. This allows
us to assume that these events are widely spaced. Additionally, all work
on the queue is flushed before handling any new work to ensure we only have
one event in flight being handled at a time.

Signed-off-by: Nathan Fontenot <nfont@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc/pseries: Cancel RTAS event scan before firmware flash

The RTAS firmware flash update is conducted using an RTAS call that is
serialized by lock_rtas() which uses spin_lock. While the flash is in
progress, rtasd performs scan for any RTAS events that are generated by
the system. rtasd keeps scanning for the RTAS events generated on the
machine. This is performed via workqueue mechanism. The rtas_event_scan()
also uses an RTAS call to scan the events, eventually trying to acquire
the spin_lock before issuing the request.

The flash update takes a while to complete and during this time, any other
RTAS call has to wait. In this case, rtas_event_scan() waits for a long time
on the spin_lock resulting in a soft lockup.

Fix: Just before the flash update is performed, the queued rtas_event_scan()
work item is cancelled from the work queue so that there is no other RTAS
call issued while the flash is in progress. After the flash completes, the
system reboots and the rtas_event_scan() is rescheduled.

Signed-off-by: Suzuki Poulose <suzuki@in.ibm.com>
Signed-off-by: Ravi Nittala <ravi.nittala@in.ibm.com>
Reported-by: Divya Vikas <divya.vikas@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

atomic: use <linux/atomic.h>

This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

powerpc: Mask smp_processor_id() false positive

The rtas_event_scan() function uses smp_processor_id() to select a
starting point in cpu_online_mask, and does so under the protection
of get_online_cpus(). This might not select the current processor
in any case, so switch to raw_smp_processor_id().

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc: Check RTAS extended log flag before checking length

The spec suggests we should first check the extended log flag before checking
the length field.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

llseek: automatically add .llseek fop

All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.

The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.

New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.

The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.

Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.

Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.

===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{
<+...
nonseekable_open(...)
...+>
}

@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{
<+...
(
nonseekable_open(...)
|
nested_open(...)
)
...+>
}

@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}

@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}

@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
<+...
(
*off = E
|
*off += E
|
func(..., off, ...)
|
E = *off
)
...+>
}

@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}

@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};

@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};

@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};

@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};

@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};

// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};

@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};

// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};

// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};

// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};

@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};

// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////

@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};

@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};

@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};

@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Julia Lawall <julia@diku.dk>
Cc: Christoph Hellwig <hch@infradead.org>

powerpc/rtasd: Don't start event scan if scan rate is zero

There appear to be Pegasos systems which have the rtas-event-scan
RTAS tokens, but on which the event scan always fails. They also
have an event-scan-rate property containing 0, which means call
event scan 0 times per minute.

So interpret a scan rate of 0 to mean don't scan at all. This fixes
the problem on the Pegasos machines and makes sense as well.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc/cpumask: Convert rtasd to new cpumask API

Use cpumask_first, cpumask_next in rtasd code.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

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>

powerpc/chrp: Use the same RTAS daemon as pSeries

The CHRP code has some fishy timer based code to scan the RTAS event
log, which uses a 1KB stack buffer and doesn't even use the results.

The pSeries code as a nicer daemon that allows userspace to read the
event log and basically uses the same RTAS interface

This patch moves rtasd.c out of platform/pseries and makes it usable
by CHRP, after removing the old crufty event log mechanism in there.

The nvram logging part of the daemon is still only available on 64-bit
since the underlying nvram management routines aren't currently shared.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>