drm/nouveau/pm: refactor deprecated strncpy

`strncpy` is deprecated for use on NUL-terminated destination strings [1].

We should prefer more robust and less ambiguous string interfaces.

A suitable replacement is `strscpy` [2] due to the fact that it guarantees
NUL-termination on the destination buffer without unnecessarily NUL-padding.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90
Cc: linux-hardening@vger.kernel.org
Signed-off-by: Justin Stitt <justinstitt@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230914-strncpy-drivers-gpu-drm-nouveau-nvkm-engine-pm-base-c-v1-1-4b09ed453f84@google.com

drm/nouveau/pm: switch to instanced constructor

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>

drm/nouveau/perfmon: use private spinlock to control exclusive access to perfmon

nvkm_subdev.mutex is going away.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>

treewide: Use struct_size() for kmalloc()-family

One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct foo {
int stuff;
void *entry[];
};

instance = kmalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = kmalloc(struct_size(instance, entry, count), GFP_KERNEL);

This patch makes the changes for kmalloc()-family (and kvmalloc()-family)
uses. It was done via automatic conversion with manual review for the
"CHECKME" non-standard cases noted below, using the following Coccinelle
script:

// pkey_cache = kmalloc(sizeof *pkey_cache + tprops->pkey_tbl_len *
// sizeof *pkey_cache->table, GFP_KERNEL);
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

- alloc(sizeof(*VAR) + COUNT * sizeof(*VAR->ELEMENT), GFP)
+ alloc(struct_size(VAR, ELEMENT, COUNT), GFP)

// mr = kzalloc(sizeof(*mr) + m * sizeof(mr->map[0]), GFP_KERNEL);
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
identifier VAR, ELEMENT;
expression COUNT;
@@

- alloc(sizeof(*VAR) + COUNT * sizeof(VAR->ELEMENT[0]), GFP)
+ alloc(struct_size(VAR, ELEMENT, COUNT), GFP)

// Same pattern, but can't trivially locate the trailing element name,
// or variable name.
@@
identifier alloc =~ "kmalloc|kzalloc|kvmalloc|kvzalloc";
expression GFP;
expression SOMETHING, COUNT, ELEMENT;
@@

- alloc(sizeof(SOMETHING) + COUNT * sizeof(ELEMENT), GFP)
+ alloc(CHECKME_struct_size(&SOMETHING, ELEMENT, COUNT), GFP)

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

drm/nouveau: nouveau: use correct string length

gcc-8 reports

drivers/gpu/drm/nouveau/nvkm/engine/pm/base.c: In function 'nvkm_perfmon_mthd':
include/linux/string.h:265:9: error: '__builtin_strncpy' specified bound 64 equals destination size [-Werror=stringop-truncation]

We need one less byte or call strlcpy() to make it a
nul-terminated string.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau: mark symbols static where possible

We get a few warnings when building kernel with W=1:
drivers/gpu/drm/nouveau/nvkm/subdev/bios/fan.c:29:1: warning: no previous prototype for 'nvbios_fan_table' [-Wmissing-prototypes]
drivers/gpu/drm/nouveau/nvkm/subdev/bios/fan.c:56:1: warning: no previous prototype for 'nvbios_fan_entry' [-Wmissing-prototypes]
drivers/gpu/drm/nouveau/nvkm/subdev/clk/gt215.c:184:1: warning: no previous prototype for 'gt215_clk_info' [-Wmissing-prototypes]
drivers/gpu/drm/nouveau/nvkm/subdev/fb/ramgt215.c:99:1: warning: no previous prototype for 'gt215_link_train_calc' [-Wmissing-prototypes]
drivers/gpu/drm/nouveau/nvkm/subdev/fb/ramgt215.c:153:1: warning: no previous prototype for 'gt215_link_train' [-Wmissing-prototypes]
drivers/gpu/drm/nouveau/nvkm/subdev/fb/ramgt215.c:271:1: warning: no previous prototype for 'gt215_link_train_init' [-Wmissing-prototypes]
....

In fact, both functions are only used in the file in which they are
declared and don't need a declaration, but can be made static.
So this patch marks these functions with 'static'.

Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/core: remove pmc_enable argument from subdev ctor

These are now specified directly in the MC subdev.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/nvif: modify nvif_unvers/nvif_unpack macros to be more obvious

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/nvif: split out perfmon interface definitions

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/nvif: move internal class identifiers to class.h

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/disp,pm: constify nvkm_object_func structures

These nvkm_object_func structures are never modified. All other
nvkm_object_func structures are declared as const.

Done with the help of Coccinelle.

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: convert to new-style nvkm_engine

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: convert user classes to new-style nvkm_object

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/device: convert user class to new-style nvkm_object

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/client: convert to new-style nvkm_object

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/device: prepare for new-style subdevs

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/engine: rename some functions to avoid upcoming conflicts

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/object: rename some functions to avoid upcoming conflicts

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/device: decouple from engine machinery

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/core: remove last printks

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: switch to subdev printk macros

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: switch to device pri macros

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: cosmetic changes

This is purely preparation for upcoming commits, there should be no
code changes here.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/device: include core/device.h automatically for subdevs/engines

Pretty much every subdev/engine is going to need access to nvkm_device
shortly to touch registers and/or output messages.

The odd placement of the includes is necessary to work around some
inter-dependencies that currently exist. This will be fixed later.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: allow zeroed signals to enable sources

Hardware signals index 0x00 are defined for some domains and they have
to be allowed to enable sources like the others.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: expose name of domains

This is going to be very useful for GF100+ because each GPC can
have its own domain of counters.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: some fixes related to sources

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: stack perfdom class under perfmon

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: swap perfmon/perfdom code to avoid forward decl in next commit

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: allow the userspace to configure sources

Signed-off-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: allow to configure domains instead of simple counters

Configuring counters from the userspace require the kernel to handle some
logic related to performance counters. Basically, it has to find a free
slot to assign a counter, to handle extra counting modes like B4/B6 and it
must return and error when it can't configure a counter.

In my opinion, the kernel should not handle all of that logic but it
should only write the configuration sent by the userspace without
checking anything. In other words, it should overwrite the configuration
even if it's already counting and do not return any errors.

This patch allows the userspace to configure a domain instead of
separate counters. This has the advantage to move all of the logic to
the userspace.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: allow the userspace to schedule hardware counters

This adds a new method NVIF_PERFCTR_V0_INIT which starts a batch of
hardware counters for sampling. This will allow the userspace to start
a monitoring session using the INIT method and to stop it with SAMPLE,
for example before and after a frame is rendered.

This commit temporarily breaks nv_perfmon but this is going to be fixed
with the upcoming patch.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: implement NVIF_PERFMON_V0_QUERY_SOURCE method

This allows to query the ID, the mask and the user-readable name of
sources for each signal.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: allow to query the number of sources for a signal

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: add concept of sources

A source (or multiplexer) is a tuple addr+mask+shift which allows to
control a block of signals. The maximum number of sources that a signal
can define is arbitrary limited to 8 and this should be large enough.
This patch allows to define multi-level of sources for a signal.

Each different sources are stored to a global list and will be exposed
to the userspace through the nvif interface in order to avoid conflicts.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: allow to monitor hardware signal index 0x00

This signal index must be always allowed even if it's not clearly
defined in a domain in order to monitor a counter like 0x03020100
because it's the default value of signals.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: use hardware signals indexes instead of user-readable names

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: change signal iter to u16

16 bits is large enough to store the maximum number of signals available
for one domain (i.e. 256).

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: allow to query signals by domain

This will allow to configure performance counters with hardware signal
indexes instead of user-readable names in an upcoming patch.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: implement NVIF_PERFMON_V0_QUERY_DOMAIN method

This allows to query the number of available domains, including the
number of hardware counter and the number of signals per domain.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: prevent creating a perfctr object when signals are not found

Since a new class has been introduced to query signals, we can now
return an error when the userspace wants to monitor unknown signals.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: reorganize the nvif interface

This commit introduces the NVIF_IOCTL_NEW_V0_PERFMON class which will be
used in order to query domains, signals and sources. This separates the
querying and the counting interface.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: remove unused nvkm_perfsig_wrap() function

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Martin Peres <martin.peres@free.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: fix a potential race condition when creating an engine context

There is always the possiblity that the ppm->context pointer would get
partially updated and accidentally would equal ctx. This would allow two
contexts to co-exist, which is not acceptable. Moving the test to the
critical section takes care of this problem.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Signed-off-by: Martin Peres <martin.peres@free.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: prevent freeing the wrong engine context

This fixes a crash when multiple PM engine contexts are created.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Martin Peres <martin.peres@free.fr>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: namespace + nvidia gpu names (no binary change)

The namespace of NVKM is being changed to nvkm_ instead of nouveau_,
which will be used for the DRM part of the driver. This is being
done in order to make it very clear as to what part of the driver a
given symbol belongs to, and as a minor step towards splitting the
DRM driver out to be able to stand on its own (for virt).

Because there's already a large amount of churn here anyway, this is
as good a time as any to also switch to NVIDIA's device and chipset
naming to ease collaboration with them.

A comparison of objdump disassemblies proves no code changes.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

drm/nouveau/pm: rename from perfmon (no binary change)

Switch to NVIDIA's name for the device.

The namespace of NVKM is being changed to nvkm_ instead of nouveau_,
which will be used for the DRM part of the driver. This is being
done in order to make it very clear as to what part of the driver a
given symbol belongs to, and as a minor step towards splitting the
DRM driver out to be able to stand on its own (for virt).

Because there's already a large amount of churn here anyway, this is
as good a time as any to also switch to NVIDIA's device and chipset
naming to ease collaboration with them.

A comparison of objdump disassemblies proves no code changes.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>