Commit Graph

12986 Commits

Author SHA1 Message Date
kib
f371322983 On exec, single-threading must be enforced before arguments space is
allocated from exec_map.  If many threads try to perform execve(2) in
parallel, the exec map is exhausted and some threads sleep
uninterruptible waiting for the map space.  Then, the thread which won
the race for the space allocation, cannot single-thread the process,
causing deadlock.

Reported and tested by:	pho (previous version)
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
2015-05-10 09:00:40 +00:00
kib
6006bf3a7d If x86 CPU implementation of the MWAIT instruction reasonably
interacts with interrupts, query ACPI and use MWAIT for entrance into
Cx sleep states.  Support C1 "I/O then halt" mode.  See Intel'
document 302223-007 "Intelб╝ Processor Vendor-Specific ACPI Interface
Specification" for description.

Move the acpi_cpu_c1() function into x86/cpu_machdep.c and use
it instead of inlining "sti; hlt" sequence in several places.

In the acpi(4) man page, besides documenting the dev.cpu.N.cx_methods
sysctl, correct the names for dev.cpu.N.{cx_usage,cx_lowest,cx_supported}
sysctls.

Both jkim and avg have some other patches implementing the mwait
functionality; this work is unrelated.  Linux does not rely on the
ACPI to provide correct tables describing Cx modes.  Instead, the
driver has pre-defined knowledge of the CPU models, it was supplied by
Intel.

Tested by:    pho (previous versions)
Sponsored by:	The FreeBSD Foundation
2015-05-09 12:28:48 +00:00
jhb
9c4c8b62fb Remove support for Xen PV domU kernels. Support for HVM domU kernels
remains.  Xen is planning to phase out support for PV upstream since it
is harder to maintain and has more overhead.  Modern x86 CPUs include
virtualization extensions that support HVM guests instead of PV guests.
In addition, the PV code was i386 only and not as well maintained recently
as the HVM code.
- Remove the i386-only NATIVE option that was used to disable certain
  components for PV kernels.  These components are now standard as they
  are on amd64.
- Remove !XENHVM bits from PV drivers.
- Remove various shims required for XEN (e.g. PT_UPDATES_FLUSH, LOAD_CR3,
  etc.)
- Remove duplicate copy of <xen/features.h>.
- Remove unused, i386-only xenstored.h.

Differential Revision:	https://reviews.freebsd.org/D2362
Reviewed by:	royger
Tested by:	royger (i386/amd64 HVM domU and amd64 PVH dom0)
Relnotes:	yes
2015-04-30 15:48:48 +00:00
whu
0b81a49657 Microsoft vmbus, storage and other related driver enhancements for HyperV.
- Vmbus multi channel support.
    - Vector interrupt support.
    - Signal optimization.
    - Storvsc driver performance improvement.
    - Scatter and gather support for storvsc driver.
    - Minor bug fix for KVP driver.
Thanks royger, jhb and delphij from FreeBSD community for the reviews
and comments. Also thanks Hovy Xu from NetApp for the contributions to
the storvsc driver.

PR:     195238
Submitted by:   whu
Reviewed by:    royger, jhb, delphij
Approved by:    royger
MFC after:      2 weeks
Relnotes:       yes
Sponsored by:   Microsoft OSTC
2015-04-29 10:12:34 +00:00
kib
cbdd03ad96 Move common code from sys/i386/i386/mp_machdep.c and
sys/amd64/amd64/mp_machdep.c, to the new common x86 source
sys/x86/x86/mp_x86.c.

Proposed and reviewed by:	jhb
Review:	https://reviews.freebsd.org/D2347
Sponsored by:	The FreeBSD Foundation
2015-04-24 16:20:56 +00:00
jhb
e4683250d1 Reassign copyright statements on several files from Advanced
Computing Technologies LLC to Hudson River Trading LLC.

Approved by:	Hudson River Trading LLC (who owns ACT LLC)
MFC after:	1 week
2015-04-23 14:22:20 +00:00
kib
9fb28191d6 Move some common code from sys/amd64/amd64/machdep.c and
sys/i386/i386/machdep.c to new file sys/x86/x86/cpu_machdep.c.  Most
of the code is related to the idle handling.

Discussed with:	pluknet
Sponsored by:	The FreeBSD Foundation
2015-04-22 12:32:14 +00:00
kib
2bf89b258b Remove duplicate definitions of MWAIT_CX hints. Identical defines in
specialreg.h are enough.

Discussed with:	mav
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-04-20 08:25:55 +00:00
kib
32cf8052a6 Remove lazy pmap switch code from i386. Naive benchmark with md(4)
shows no difference with the code removed.

On both amd64 and i386, assert that a released pmap is not active.

Proposed and reviewed by:	alc
Discussed with:	Svatopluk Kraus <onwahe@gmail.com>, peter
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
2015-04-18 21:23:16 +00:00
kib
3278a55c03 Add config option PAE_TABLES for the i386 kernel. It switches pmap to
use PAE format for the page tables, but does not incur other
consequences of the full PAE config.  In particular, vm_paddr_t and
bus_addr_t are left 32bit, and max supported memory is still limited
by 4GB.

The option allows to have nx permissions for memory mappings on i386
kernel, while keeping the usual i386 KBI and avoiding the kernel data
sizing problems typical for the PAE config.

Intel documented that the PAE format for page tables is available
starting with the Pentium Pro, but it is possible that the plain
Pentium CPUs have the required support (Appendix H).  The goal is to
enable the option and non-exec mappings on i386 for the GENERIC
kernel.  Anybody wanting a useful system on 486, have to reconfigure
the modern i386 kernel anyway.

Discussed with:	alc, jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks
2015-04-13 15:22:45 +00:00
kib
006ec96529 Explain that vm_page_array is mapped to describe the memory, not the
memory itself.  Provide the formula to calculate the number of
required page tables.  Correct the size of the struct vm_page for
non-PAE case.

Reviewed by:	alc, jhb (previous version)
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-04-08 19:46:13 +00:00
rstone
57feb6fb43 Fix integer truncation bug in malloc(9)
A couple of internal functions used by malloc(9) and uma truncated
a size_t down to an int.  This could cause any number of issues
(e.g. indefinite sleeps, memory corruption) if any kernel
subsystem tried to allocate 2GB or more through malloc.  zfs would
attempt such an allocation when run on a system with 2TB or more
of RAM.

Note to self: When this is MFCed, sparc64 needs the same fix.

Differential revision:	https://reviews.freebsd.org/D2106
Reviewed by:	kib
Reported by:	Michael Fuckner <michael@fuckner.net>
Tested by:	Michael Fuckner <michael@fuckner.net>
MFC after:	2 weeks
2015-04-01 12:42:26 +00:00
jhb
4e5400d652 Wait 100 microseconds for a local APIC to dispatch each startup-related IPI
rather than 20.  The MP 1.4 specification states in Appendix B.2:

  "A period of 20 microseconds should be sufficient for IPI dispatch to
   complete under normal operating conditions".

(Note that this appears to be separate from the 10 millisecond (INIT) and
200 microsecond (STARTUP) waits after the IPIs are dispatched.)  The
Intel SDM is silent on this issue as far as I can tell.

At least some hardware requires 60 microseconds as noted in the PR, so
bump this to 100 to be on the safe side.

PR:		197756
Reported by:	zaphod@berentweb.com
MFC after:	1 week
2015-03-30 20:13:22 +00:00
jhb
db1b65b9c2 Apply r276208 to non-amd64 NOTES files as well to fix tinderbox builds
run under a system using vt(4) instead of syscons(4):

Use compiled in default keymaps which are available both in syscons and vt.
2015-03-25 15:51:41 +00:00
kib
b178649de8 Use VT-d interrupt remapping block (IR) to perform FSB messages
translation.  In particular, despite IO-APICs only take 8bit apic id,
IR translation structures accept 32bit APIC Id, which allows x2APIC
mode to function properly.  Extend msi_cpu of struct msi_intrsrc and
io_cpu of ioapic_intsrc to full int from one byte.

KPI of IR is isolated into the x86/iommu/iommu_intrmap.h, to avoid
bringing all dmar headers into interrupt code. The non-PCI(e) devices
which generate message interrupts on FSB require special handling. The
HPET FSB interrupts are remapped, while DMAR interrupts are not.

For each msi and ioapic interrupt source, the iommu cookie is added,
which is in fact index of the IRE (interrupt remap entry) in the IR
table. Cookie is made at the source allocation time, and then used at
the map time to fill both IRE and device registers. The MSI
address/data registers and IO-APIC redirection registers are
programmed with the special values which are recognized by IR and used
to restore the IRE index, to find proper delivery mode and target.
Map all MSI interrupts in the block when msi_map() is called.

Since an interrupt source setup and dismantle code are done in the
non-sleepable context, flushing interrupt entries cache in the IR
hardware, which is done async and ideally waits for the interrupt,
requires busy-wait for queue to drain.  The dmar_qi_wait_for_seq() is
modified to take a boolean argument requesting busy-wait for the
written sequence number instead of waiting for interrupt.

Some interrupts are configured before IR is initialized, e.g. ACPI
SCI.  Add intr_reprogram() function to reprogram all already
configured interrupts, and call it immediately before an IR unit is
enabled.  There is still a small window after the IO-APIC redirection
entry is reprogrammed with cookie but before the unit is enabled, but
to fix this properly, IR must be started much earlier.

Add workarounds for 5500 and X58 northbridges, some revisions of which
have severe flaws in handling IR.  Use the same identification methods
as employed by Linux.

Review:	https://reviews.freebsd.org/D1892
Reviewed by:	neel
Discussed with:	jhb
Tested by:	glebius, pho (previous versions)
Sponsored by:	The FreeBSD Foundation
MFC after:	3 weeks
2015-03-19 13:57:47 +00:00
kib
e3e7e80678 Remove write-only variable.
Sponsored by:	The FreeBSD Foundation
MFC after:	3 days
2015-03-12 20:14:48 +00:00
jhb
c1c1fd8e25 Only schedule interrupts on a single hyperthread of a modern Intel CPU core
by default.  Previously we used a single hyperthread on Pentium4-era
cores but used both hyperthreads on more recent CPUs.

MFC after:	2 weeks
2015-03-06 20:34:28 +00:00
rstone
e40d09375f Implement interface to create SR-IOV Virtual Functions
Implement the interace to create SR-IOV Virtual Functions (VFs).
When a driver registers that they support SR-IOV by calling
pci_setup_iov(), the SR-IOV code creates a new node in /dev/iov
for that device.  An ioctl can be invoked on that device to
create VFs and have the driver initialize them.

At this point, allocating memory I/O windows (BARs) is not
supported.

Differential Revision:	https://reviews.freebsd.org/D76
Reviewed by:		jhb
MFC after: 		1 month
Sponsored by:		Sandvine Inc.
2015-03-01 00:40:09 +00:00
kib
59184505da Supposed fix for some SandyBridge mobile CPUs hang on AP startup when
x2APIC mode is detected and enabled.  Current theory is that switching
the APIC mode while an IPI is in flight might be the issue.

Postpone switching to x2APIC mode until we are guaranteed that all
starting IPIs are already send and aknowledged.  Use aps_ready signal
as an indication that the BSP is done with us.

Tested by:	adrian
Sponsored by:	The FreeBSD Foundation
MFC after:	2 months
2015-02-28 20:37:38 +00:00
jhb
4145efe339 Ensure that the supplied data length is large enough to hold the base
FPU state to avoid passing a negative length to fpusetregs() / npxsetregs().

Differential Revision:	https://reviews.freebsd.org/D1861
Reviewed by:	kib, emaste
2015-02-18 23:34:03 +00:00
kib
7a89c3df60 Initialize x2APIC mode on the resume path before accessing LAPIC.
Remove unneeded disable of LAPIC in the native_lapic_xapic_mode().  We
attempt to send wakeup IPI on the resume path right after BSP wakeup,
so disabling is wrong.

Reported and tested by:	glebius, "Ranjan1018 ." <214748mv@gmail.com>
Sponsored by:	The FreeBSD Foundation
MFC after:	2 months
2015-02-16 21:56:19 +00:00
markj
fc1485dfdc Add support for decoding multibyte NOPs.
Differential Revision:	https://reviews.freebsd.org/D1830
Reviewed by:	jhb, kib
MFC after:	2 weeks
Sponsored by:	EMC / Isilon Storage Divison
2015-02-13 01:35:53 +00:00
kib
0754f0eac9 Add x2APIC support. Enable it by default if CPU is capable. The
hw.x2apic_enable tunable allows disabling it from the loader prompt.

To closely repeat effects of the uncached memory ops when accessing
registers in the xAPIC mode, the x2APIC writes to MSRs are preceeded
by mfence, except for the EOI notifications.  This is probably too
strict, only ICR writes to send IPI require serialization to ensure
that other CPUs see the previous actions when IPI is delivered.  This
may be changed later.

In vmm justreturn IPI handler, call doreti_iret instead of doing iretd
inline, to handle corner conditions.

Note that the patch only switches LAPICs into x2APIC mode. It does not
enables FreeBSD to support > 255 CPUs, which requires parsing x2APIC
MADT entries and doing interrupts remapping, but is the required step
on the way.

Reviewed by:	neel
Tested by:	pho (real hardware), neel (on bhyve)
Discussed with:	jhb, grehan
Sponsored by:	The FreeBSD Foundation
MFC after:	2 months
2015-02-09 21:00:56 +00:00
jhb
9dfc36d985 Revert the IPI startup sequence to match what is described in the
Intel Multiprocessor Specification v1.4.  The Intel SDM claims that
the INIT IPIs here are invalid, but other systems follow the MP
spec instead.

While here, fix the IPI wait routine to accept a timeout in microseconds
instead of a raw spin count, and don't spin forever during AP startup.
Instead, panic if a STARTUP IPI is not delivered after 20 us.

PR:		196542
Differential Revision:	https://reviews.freebsd.org/D1719
MFC after:	2 weeks
2015-02-06 18:19:59 +00:00
bryanv
25ce9181cf Generalized parts of the XEN timer code into a generic pvclock
KVM clock shares the same data structures between the guest and the host
as Xen so it makes sense to just have a single copy of this code.

Differential Revision: https://reviews.freebsd.org/D1429
Reviewed by:	royger (eariler version)
MFC after:	1 month
2015-02-04 08:26:43 +00:00
kib
3bbc91d138 Do not qualify the mcontext_t *mcp argument for set_mcontext(9) as
const.  On x86, even after the machine context is supposedly read into
the struct ucontext, lazy FPU state save code might only mark the FPU
data as hardware-owned.  Later, set_fpcontext() needs to fetch the
state from hardware, modifying the *mcp.

The set_mcontext(9) is called from sigreturn(2) and setcontext(2)
implementations and old create_thread(2) interface, which throw the
*mcp out after the set_mcontext() call.

Reported by:	dim
Discussed with:	jhb
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-01-31 21:43:46 +00:00
kib
b8f7b5ec8d Remove Giant from /dev/mem and /dev/kmem. It is definitely not needed
for i386, and from the code inspection, nothing in the
arm/mips/sparc64 implementations depends on it.

Discussed with:	imp, nwhitehorn
Sponsored by:	The FreeBSD Foundation
MFC after:	3 weeks
2015-01-24 12:51:15 +00:00
royger
0c5b62d3d2 loader: implement multiboot support for Xen Dom0
Implement a subset of the multiboot specification in order to boot Xen
and a FreeBSD Dom0 from the FreeBSD bootloader. This multiboot
implementation is tailored to boot Xen and FreeBSD Dom0, and it will
most surely fail to boot any other multiboot compilant kernel.

In order to detect and boot the Xen microkernel, two new file formats
are added to the bootloader, multiboot and multiboot_obj. Multiboot
support must be tested before regular ELF support, since Xen is a
multiboot kernel that also uses ELF. After a multiboot kernel is
detected, all the other loaded kernels/modules are parsed by the
multiboot_obj format.

The layout of the loaded objects in memory is the following; first the
Xen kernel is loaded as a 32bit ELF into memory (Xen will switch to
long mode by itself), after that the FreeBSD kernel is loaded as a RAW
file (Xen will parse and load it using it's internal ELF loader), and
finally the metadata and the modules are loaded using the native
FreeBSD way. After everything is loaded we jump into Xen's entry point
using a small trampoline. The order of the multiboot modules passed to
Xen is the following, the first module is the RAW FreeBSD kernel, and
the second module is the metadata and the FreeBSD modules.

Since Xen will relocate the memory position of the second
multiboot module (the one that contains the metadata and native
FreeBSD modules), we need to stash the original modulep address inside
of the metadata itself in order to recalculate its position once
booted. This also means the metadata must come before the loaded
modules, so after loading the FreeBSD kernel a portion of memory is
reserved in order to place the metadata before booting.

In order to tell the loader to boot Xen and then the FreeBSD kernel the
following has to be added to the /boot/loader.conf file:

xen_cmdline="dom0_mem=1024M dom0_max_vcpus=2 dom0pvh=1 console=com1,vga"
xen_kernel="/boot/xen"

The first argument contains the command line that will be passed to the Xen
kernel, while the second argument is the path to the Xen kernel itself. This
can also be done manually from the loader command line, by for example
typing the following set of commands:

OK unload
OK load /boot/xen dom0_mem=1024M dom0_max_vcpus=2 dom0pvh=1 console=com1,vga
OK load kernel
OK load zfs
OK load if_tap
OK load ...
OK boot

Sponsored by: Citrix Systems R&D
Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D517

For the Forth bits:
Submitted by: Julien Grall <julien.grall AT citrix.com>
2015-01-15 16:27:20 +00:00
kib
11969484c8 For x86, read MAXPHYADDR, defined in SDM vol 3 4.1.4 Enumeration of Paging
Features by CPUID as CPUID.80000008H:EAX[7:0], into variable cpu_maxphyaddr.

Reviewed by:	alc
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2015-01-12 07:36:25 +00:00
imp
8a8cd95245 Need to include opt_cpu.h to access CPU_DISABLE_SSE option. Thankfully, this
only broke i686 configs that disabled SSE.

Submitted by: nyan@
2015-01-08 17:46:42 +00:00
imp
a1d87ddc10 Don't call the SSE routines when they aren't enabled (or even compiled
into the kernel).
2015-01-08 00:39:40 +00:00
markj
7e7e145818 Factor out duplicated code from dumpsys() on each architecture into generic
code in sys/kern/kern_dump.c. Most dumpsys() implementations are nearly
identical and simply redefine a number of constants and helper subroutines;
a generic implementation will make it easier to implement features around
kernel core dumps. This change does not alter any minidump code and should
have no functional impact.

PR:		193873
Differential Revision:	https://reviews.freebsd.org/D904
Submitted by:	Conrad Meyer <conrad.meyer@isilon.com>
Reviewed by:	jhibbits (earlier version)
Sponsored by:	EMC / Isilon Storage Division
2015-01-07 01:01:39 +00:00
jhb
c3d1954342 Remove "New" label from NFSCL/NFSD now that they are the only NFS
client/server.  While here, remove duplicate NFSCL from sys/conf/NOTES.

Approved by:	rmacklem
2015-01-06 16:15:57 +00:00
jhb
55d0376a65 On some Intel CPUs with a P-state but not C-state invariant TSC the TSC
may also halt in C2 and not just C3 (it seems that in some cases the BIOS
advertises its C3 state as a C2 state in _CST).  Just play it safe and
disable both C2 and C3 states if a user forces the use of the TSC as the
timecounter on such CPUs.

PR:		192316
Differential Revision:	https://reviews.freebsd.org/D1441
No objection from:	jkim
MFC after:	1 week
2015-01-05 20:44:44 +00:00
marius
0da0078579 Exclude drivers which build but don't actually work with PAE enabled,
missed in r276377
2015-01-05 19:15:35 +00:00
scottl
445e8d91ed Garbage collect the asr driver. Hardware for it has not been produced in
roughly 10 years, and the driver has not enjoyed any significant maintenance
since long before that.  Despite well-meaning efforts from a number of
people, myself included, it never made the jump to 64-bit and was relegated
to the back-corners of i386.  Now its frailty is hampering forward progress
with Clang.  Any renewed engineering efforts are of course welcome and can
happen outside of the tree.  No MFC of this is planned.
2015-01-02 05:34:14 +00:00
dchagin
4026f410fd Regen after r276508, r276509. 2015-01-01 18:43:31 +00:00
dchagin
dc3f8ca4f8 Correct an argument status of wait4 syscall for Linuxulator.
Forgot about i386.

MFC after:	1 week
2015-01-01 18:41:34 +00:00
marius
05aa3e23fe - No longer exclude malo(4) and mwl(4), they have been fixed in r275870
and r275871 respectively to build with PAE enabled.
- For the PAE kernel configuration file, no longer exclude devices that
  are known to be 64-bit DMA clean from amd64.

MFC after:	3 days
2014-12-29 20:33:34 +00:00
markj
7ea63e4fb4 Restore the trap type argument to the DTrace trap hook, removed in r268600.
It's redundant at the moment since it can be obtained from the trapframe
on the architectures where DTrace is supported, but this won't be the case
with ARM.
2014-12-23 15:38:19 +00:00
imp
256101c95b Where appropriate, use the modern terms for the one true time base
(UTC) rather than the archaic (GMT) in comments. Except where the
comments are making fun of people doing this (and pedants who insist
on the new terms).
2014-12-21 05:07:11 +00:00
gnn
d5b2a401e7 This configuration file removes several debugging options, including
WITNESS and INVARIANTS checking, which are known to have significant
performance impact on running systems.  When benchmarking new features
this kernel should be used instead of the standard GENERIC.
This kernel configuration should never appear outside of the HEAD
of the FreeBSD tree.
2014-12-02 19:55:43 +00:00
jhb
b4b910ded7 MFamd64: Check for invalid flags in the machine context in sigreturn()
and setcontext().
2014-11-25 12:52:00 +00:00
emaste
fda27c9937 Revert r274772: it is not valid on MIPS
Reported by:	sbruno
2014-11-25 03:50:31 +00:00
jhb
1671ac9155 Improve support for XSAVE with debuggers.
- Dump an NT_X86_XSTATE note if XSAVE is in use. This note is designed
  to match what Linux does in that 1) it dumps the entire XSAVE area
  including the fxsave state, and 2) it stashes a copy of the current
  xsave mask in the unused padding between the fxsave state and the
  xstate header at the same location used by Linux.
- Teach readelf() to recognize NT_X86_XSTATE notes.
- Change PT_GET/SETXSTATE to take the entire XSAVE state instead of
  only the extra portion. This avoids having to always make two
  ptrace() calls to get or set the full XSAVE state.
- Add a PT_GET_XSTATE_INFO which returns the length of the current
  XSTATE save area (so the size of the buffer needed for PT_GETXSTATE)
  and the current XSAVE mask (%xcr0).

Differential Revision:	https://reviews.freebsd.org/D1193
Reviewed by:	kib
MFC after:	2 weeks
2014-11-21 20:53:17 +00:00
emaste
c7e313326d Use canonical __PIC__ flag
It is automatically set when -fPIC is passed to the compiler.

Reviewed by:	dim, kib
Sponsored by:	The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D1179
2014-11-21 02:05:48 +00:00
jhb
86ac03a3f7 Lock spic(4) and mark it MPSAFE:
- Add a per-softc mutex as a driver lock.
- Use callout(9) instead of timeout(9).
- Set softc pointer in si_drv1 of cdev instead of looking softc
  up via devclass in cdev methods.

Tested by:	no one
2014-11-20 20:24:30 +00:00
imp
e1fec13f7c opt_global.h is included automatically in the build. No need to
explicitly include it in these places.

Sponsored by: Netflix
2014-11-18 17:06:56 +00:00
alc
aeebd38e4b Enable the use of VM_PHYSSEG_SPARSE on amd64 and i386, making it the default
on i386 PAE.  Previously, VM_PHYSSEG_SPARSE could not be used on amd64 and
i386 because vm_page_startup() would not create vm_page structures for the
kernel page table pages allocated during pmap_bootstrap() but those vm_page
structures are needed when the kernel attempts to promote the corresponding
kernel virtual addresses to superpage mappings.  To address this problem, a
new public function, vm_phys_add_seg(), is introduced and vm_phys_init() is
updated to reflect the creation of vm_phys_seg structures by calls to
vm_phys_add_seg().

Discussed with:	Svatopluk Kraus
MFC after:	3 weeks
Sponsored by:	EMC / Isilon Storage Division
2014-11-15 23:40:44 +00:00
kib
b4ef709604 Remove the no-at variants of the kern_xx() syscall helpers. E.g., we
have both kern_open() and kern_openat(); change the callers to use
kern_openat().

This removes one (sometimes two) levels of indirection and
consolidates arguments checks.

Reviewed by:	mckusick
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
2014-11-13 18:01:51 +00:00