Both s_len and s_size are ssize_t, so their differece is also more
properly a ssize_t not a size_t. Also, assert that len is <= size when
we enter. This should always be the case. Ensure that we have that one
byte that we write to the end of the buffer before we do so, though
the error should already be set on the buffer if not, and the only
times we supply 'partial' buffers they should be plenty large.
Reviewed by: cem, jhb (prior version, I did cem's suggestion)
Differential Revsion: https://reviews.freebsd.org/D26752
Change the zone setup:
- Allow slabs to be returned to the OS
- Set the number of slots to the max devctl will queue before discarding
- Reserve 2% of the max (capped at 100) for low memory allocations
- Disable per-cpu caching since we don't need it and we avoid some pathologies
Change the alloation strategiy a bit:
- If a normal allocation fails, try to get the reserve
- If a reserve allocation fails, re-use the oldest-queued entry for storage
- If there's a weird race/failure and nothing on the queue to steal, return NULL
This addresses two main issues in the old code:
- If devd had died, and we're generating a lot of messages, we have an
unbounded leak. This new scheme avoids the issue that lead to this.
- The MPASS that was 'sure' the allocation couldn't have failed turned out
to be wrong in some rare cases. The new code doesn't make this assumption.
Since we reserve only 2% of the space, we go from about 1MB of
allocation all the time to more like 50kB for the reserve.
Reviewed by: markj@
Differential Revision: https://reviews.freebsd.org/D26448
Convert two different sysctl to using sbuf. First, for all the default
sysctls we implement for each device driver that's attached. This is a
pure sbuf conversion.
Second, convert sysctl_devices to fill its buffer with sbuf rather
than a hand-rolled crappy thing I wrote years ago.
Reviewed by: cem, markj
Differential Revision: https://reviews.freebsd.org/D26206
devctl_notify_f isn't needed, so retire it. The flags argument is now
unused, so rather than keep it around, retire it. Convert all old
users of it to devctl_notify(). This path no longer sleeps, so is safe
to call from any context. Since it doesn't sleep, it doesn't need to
know if it is OK to sleep or not.
Reviewed by: markj@
Differential Revision: https://reviews.freebsd.org/D26140
Convert the memory management of devctl. Rewrite if to make better
use of memory. This eliminates several mallocs (5? worse case) needed
to send a message. It's now possible to always send a message, though
if things are really backed up the oldest message will be dropped to
free up space for the newest.
Add a static bus_child_{location,pnpinfo}_sb to start migrating to
sbuf instead of buffer + length. Use it in the new code. Other code
will be converted later (bus_child_*_str is only used inside of
subr_bus.c, though implemented in ~100 places in the tree).
Reviewed by: markj@
Differential Revision: https://reviews.freebsd.org/D26140
We have both a system of 'kern' and of 'kernel'. Prefer the latter and
convert this notification to use 'kernel' instead of 'kern'. As a
transition period, continue to also generate the 'kern' notification
until sometime after FreeBSD 13 is branched.
MFC After: 3 days
hw.bus.devctl_disable has tagged been obsolete for a decade. Remove it. Also
remove some long obsolete comments. This was done and backed out once in 2014,
but we've had enough releases with the 'new' method of setting queue length that
we can just remove this sysctl now (stable/11, stable/12 and current all don't
reference it).
These functions were introduced before UMA started ensuring that freed
memory gets placed in domain-local caches. They no longer serve any
purpose since UMA now provides their functionality by default. Remove
them to simplyify the kernel memory allocator interfaces a bit.
Reviewed by: cem, kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D25937
hw.bus.info was added in r68522 as a node, but there was never anything
connected "behind" it. Its only purpose is to return a struct u_businfo.
The only in-base consumer are devinfo(3)/devinfo(8).
Rewrite the handler as SYSCTL_PROC and mark it as MPSAFE and read-only
as there never was a writable path.
Reviewed by: kib
Approved by: kib (mentor)
Sponsored by: Mysterious Code Ltd.
Differential Revision: https://reviews.freebsd.org/D25321
r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.
This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.
Mark all obvious cases as MPSAFE. All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT
Approved by: kib (mentor, blanket)
Commented by: kib, gallatin, melifaro
Differential Revision: https://reviews.freebsd.org/D23718
Remove assumptions about the minimum MINALLOCSIZE, in order to allow
testing of smaller MINALLOCSIZE. A following patch will lower the
MINALLOCSIZE, but not so much that the present patch is required for
correctness at these sites.
Reviewed by: jeff, markj
Sponsored by: Dell EMC Isilon
Delay the attachment of children, when requested, until after interrutps are
running. This is often needed to allow children to run transactions on i2c or
spi busses. It's a common enough idiom that it will be useful to have its own
wrapper.
Reviewed by: ian
Differential Revision: https://reviews.freebsd.org/D21465
Since we are trying to bind device interrupt threads to the device domain,
it should have sense to make memory often accessed by them local. If domain
is not known, fall back to round-robin.
MFC after: 2 weeks
Sponsored by: iXsystems, Inc.
PowerPC, and possibly other architectures, use different address ranges for
PCI space vs physical address space, which is only mapped at resource
activation time, when the BAR gets written. The DRM kernel modules do not
activate the rman resources, soas not to waste KVA, instead only mapping
parts of the PCI memory at a time. This introduces a
BUS_TRANSLATE_RESOURCE() method, implemented in the Open Firmware/FDT PCI
driver, to perform this necessary translation without activating the
resource.
In addition to system KPI changes, LinuxKPI is updated to handle a
big-endian host, by adding proper endian swaps to the I/O functions.
Submitted by: mmacy
Reported by: hselasky
Differential Revision: https://reviews.freebsd.org/D21096
device_printf does multiple calls to printf allowing other console messages to
be inserted between the device name, and the rest of the message. This change
uses sbuf to compose to two into a single buffer, and prints it all at once.
It exposes an sbuf drain function (drain-to-printf) for common use.
Update documentation to match; some unit tests included.
Submitted by: jmg
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D16690
It performs BUS_RESET_CHILD() on the parental bus and the specified
device.
Reviewed by: imp (previous version), jhb (previous version)
Sponsored by: Mellanox Technologies
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D19646
The methods BUS_RESET_PREPARE(), BUS_RESET(), and BUS_RESET_POST()
should be implemented by bus which can provide reset to a device. The
methods are described in inline doxygen comments.
Code only provides BUS_RESET_PREPARE() and BUS_RESET_POST() helpers
instead of default implementation, because actual bus needs to handle
device state around reset, while helpers provide the other half of
typical prepare/post code.
Reviewed by: imp (previous version), jhb (previous version)
Sponsored by: Mellanox Technologies
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D19646
When the device is in attaching state, detach should return
EBUSY instead of success. In other case, there could be race
between attach and detach during the driver unloading.
If driver goes sleep and releases GIANT lock during attaching,
unloading module could start. In such case when attach continues
after module unload, page fault "supervisor read instruction,
page not present" occurred.
This patch works around the real issue, which is a locking
deficiency of the busses.
Submitted by: Rafal Kozik <rk@semihalf.com>
Reviewed by: imp
Obtained from: Semihalf
MFC after: 2 weeks
Sponsored by: Amazon, Inc.
Differential Revision: https://reviews.freebsd.org/D19375
The goal of this change is to fix a problem with PCI shared interrupts
during suspend and resume.
I have observed a couple of variations of the following scenario.
Devices A and B are on the same PCI bus and share the same interrupt.
Device A's driver is suspended first and the device is powered down.
Device B generates an interrupt. Interrupt handlers of both drivers are
called. Device A's interrupt handler accesses registers of the powered
down device and gets back bogus values (I assume all 0xff). That data is
interpreted as interrupt status bits, etc. So, the interrupt handler
gets confused and may produce some noise or enter an infinite loop, etc.
This change affects only PCI devices. The pci(4) bus driver marks a
child's interrupt handler as suspended after the child's suspend method
is called and before the device is powered down. This is done only for
traditional PCI interrupts, because only they can be shared.
At the moment the change is only for x86.
Notable changes in core subsystems / interfaces:
- BUS_SUSPEND_INTR and BUS_RESUME_INTR methods are added to bus
interface along with convenience functions bus_suspend_intr and
bus_resume_intr;
- rman_set_irq_cookie and rman_get_irq_cookie functions are added to
provide a way to associate an interrupt resource with an interrupt
cookie;
- intr_event_suspend_handler and intr_event_resume_handler functions
are added to the MI interrupt handler interface.
I added two new interrupt handler flags, IH_SUSP and IH_CHANGED, to
implement the new intr_event functions. IH_SUSP marks a suspended
interrupt handler. IH_CHANGED is used to implement a barrier that
ensures that a change to the interrupt handler's state is visible
to future interrupts.
While there, I fixed some whitespace issues in comments and changed a
couple of logically boolean variables to be bool.
MFC after: 1 month (maybe)
Differential Revision: https://reviews.freebsd.org/D15755
This patch utilizes the fixed_devclass attribute in order to make sure
other acpi devices with params don't get confused for an EC device.
The existing code assumes that acpi_ec_probe is only ever called with a
dereferencable acpi param. Aside from being incorrect because other
devices of ACPI_TYPE_DEVICE may be probed here which aren't ec devices,
(and they may have set acpi private data), it is even more nefarious if
another ACPI driver uses private data which is not dereferancable. This
will result in a pointer deref during boot and therefore boot failure.
On X86, as it stands today, no other devices actually do this (acpi_cpu
checks for PROCESSOR type devices) and so there is no issue. I ran into
this because I am adding such a device which gets probed before
acpi_ec_probe and sets private data. If ARM ever has an EC, I think
they'd run into this issue as well.
There have been several iterations of this patch. Earlier
iterations had ECDT enumerated ECs not call into the probe/attach
functions of this driver. This change was Suggested by: jhb@.
Reviewed by: jhb
Approved by: emaste (mentor)
Differential Revision: https://reviews.freebsd.org/D16635
given in random(4).
This includes updating of the relevant man pages, and no-longer-used
harvesting parameters.
Ensure that the pseudo-unit-test still does something useful, now also
with the "other" algorithm instead of Yarrow.
PR: 230870
Reviewed by: cem
Approved by: so(delphij,gtetlow)
Approved by: re(marius)
Differential Revision: https://reviews.freebsd.org/D16898
This flag is set once the device has been successfully attached. When
set, it inhibits devmatch from trying to match the device. This in
turn allows kldunload to work as expected. Prior to the change, the
driver would immediately reload because devmatch had no notion that
the driver had once been attached, and therefore shouldn't participate
in further matching.
Differential Revision: https://reviews.freebsd.org/D16735
This adds it to devctl, libdevctl, defines the two IOCTLs and
implements the kernel bits. causes any new drivers that are added via
kldload to be deferred until a 'thaw' comes in. These do not stack: it
is an error to freeze while frozen, or thaw while thawed.
Differential Revision: https://reviews.freebsd.org/D16735
It's likely that the header was needed in the past for swi(9).
But now that code does not use swi(9) or any other interfaces defined
in sys/interrupt.h.
MFC after: 1 week
sbuf to make it safe. Callers are expected to add the " " around it,
if needed.
Sponsored by: Netflix
Differential Review: https://reviews.freebsd.org/D16026
Rather than using fixed-length strings, pack them into a string table
to return. Also expand the buffer from ~300 charaters to 3k. This should
be enough, even for USB.
This fixes a problem where USB pnp info is truncated on return to
userland.
Differential Revision: https://reviews.freebsd.org/D15629
If you add a child to a device that has quiet children, we'll
automatically set the quiet flag on the children, and its
children.
This is indended for things like CPU that have a large amount of
repetition in booting that adds nothing.
For most buses all children are equal, so the order does not matter.
Other buses, such as acpi, carefully order their child devices to
express implicit dependencies between them. For such buses it is safer
to bring down devices in the reverse order.
I believe that this is the reason why hpet_suspend had to be disabled.
Some drivers depend on a working event timer until they are suspended.
But previously we would suspend hpet very early.
I tested this change by makinbg hpet_suspend actually stop HPET timers
and tested that too.
Note that this change is not a complete solution as it does not take
into account bus passes.
A better approach would be to track the actual attach order of the
devices and to use the reverse of that.
Reviewed by: imp, mav
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D15291
gone_in(majar, msg); If we're running in FreeBSD major, tell
the user this code may be deleted soon.
If we're running in FreeBSD major - 1,
the the user is deprecated and will
be gone in major.
Otherwise say nothing.
gone_in_dev(dev, major, msg) Just like gone_in, except use device_printf.
New tunable / sysctl debug.oboslete_panic: 0 - don't panic,
1 - panic in major or newer , 2 - panic in major - 1 or newer
default: 0
if NO_OBSOLETE_CODE is defined, then both of these turn into compile
time errors when building for major. Add options NO_OBSOLETE_CODE to
kernel build system.
This lets us tag code that's going away so users know it will be gone,
as well as automatically manage things.
Differential Review: https://reviews.freebsd.org/D13818
Uses of mallocarray(9).
The use of mallocarray(9) has rocketed the required swap to build FreeBSD.
This is likely caused by the allocation size attributes which put extra pressure
on the compiler.
Given that most of these checks are superfluous we have to choose better
where to use mallocarray(9). We still have more uses of mallocarray(9) but
hopefully this is enough to bring swap usage to a reasonable level.
Reported by: wosch
PR: 225197
Focus on code where we are doing multiplications within malloc(9). None of
these ire likely to overflow, however the change is still useful as some
static checkers can benefit from the allocation attributes we use for
mallocarray.
This initial sweep only covers malloc(9) calls with M_NOWAIT. No good
reason but I started doing the changes before r327796 and at that time it
was convenient to make sure the sorrounding code could handle NULL values.
X-Differential revision: https://reviews.freebsd.org/D13837
