Add user events support to kernel events which are not associated with any
kernel mechanism but are triggered by user level code. This is useful for
adding user level events to an event handler that may also be monitoring
kernel events.
Approved by: rwatson (co-mentor)
The touch event filter is called when a kernel event data is possibly
updated. There are two hook points. First, during a kevent() system
call. Second, when an event has been triggered.
Approved by: rwatson (co-mentor)
TCP_SORECEIVE_STREAM for the time being.
Requested by: brooks
Once compiled in make it easily switchable for testers by using a tuneable
net.inet.tcp.soreceive_stream
and a corresponding read-only sysctl to report the current state.
Suggested by: rwatson
MFC after: 2 days
- In 8.x and above the run-queue locks are nomore shared even in the
HTT case, so remove the special case.
- The deadlock explained in the removed comment here is still possible
even with different locks, with the contribution of tdq_lock_pair().
An explanation is here:
(hypotesis: a thread needs to migrate on another CPU, thread1 is doing
sched_switch_migrate() and thread2 is the one handling the sched_switch()
request or in other words, thread1 is the thread that needs to migrate
and thread2 is a thread that is going to be preempted, most likely an
idle thread. Also, 'old' is referred to the context (in terms of
run-queue and CPU) thread1 is leaving and 'new' is referred to the
context thread1 is going into. Finally, thread3 is doing tdq_idletd()
or sched_balance() and definitively doing tdq_lock_pair())
* thread1 blocks its td_lock. Now td_lock is 'blocked'
* thread1 drops its old runqueue lock
* thread1 acquires the new runqueue lock
* thread1 adds itself to the new runqueue and sends an IPI_PREEMPT
through tdq_notify() to the new CPU
* thread1 drops the new lock
* thread3, scanning the runqueues, locks the old lock
* thread2 received the IPI_PREEMPT and does thread_lock() with td_lock
pointing to the new runqueue
* thread3 wants to acquire the new runqueue lock, but it can't because
it is held by thread2 so it spins
* thread1 wants to acquire old lock, but as long as it is held by
thread3 it can't
* thread2 going further, at some point wants to switchin in thread1,
but it will wait forever because thread1->td_lock is in blocked state
This deadlock has been manifested mostly on 7.x and reported several time
on mailing lists under the voice 'spinlock held too long'.
Many thanks to des@ for having worked hard on producing suitable textdumps
and Jeff for help on the comment wording.
Reviewed by: jeff
Reported by: des, others
Tested by: des, Giovanni Trematerra
<giovanni dot trematerra at gmail dot com>
(STABLE_7 based version)
The problem was introduced in SVN 180608/ rev 1.114 and affects
all users of callout_reset() (including select, usleep, setitimer).
A better fix probably involves replicating 'ticks' in the
struct callout_cpu; this commit is just a temporary thing so that
we can MFC it after a suitable test time and RE approval.
MFC after: 3 days
longs. Since 32bit processes longs are 4 bytes, 64bit kernel may copy in
or out 4 bytes more then the process expected.
Calculate the amount of bytes to copy taking into account size of fd_set
for the current process ABI.
Diagnosed and tested by: Peter Jeremy <peterjeremy acm org>
Reviewed by: jhb
MFC after: 1 week
The hook calls vn_fullpath(9), that should not be executed with a vnode
lock held.
Reported by: Bruce Cran <bruce cran org uk>
Tested by: pho
MFC after: 3 days
vn_start_write(NULL, &mp) from operating on potentially freed or reused
struct mount *.
Remove unmatched vfs_rel() in cleanup.
Noted and reviewed by: tegge
Tested by: pho
MFC after: 3 days
Now that pty(4) is a loadable kernel module, I'd better move /dev/ptmx
in there as well. This means that pty(4) now provides almost all
pseudo-terminal compatibility code. This means it's very easy to test
whether applications use the proper library interfaces when allocating
pseudo-terminals (namely posix_openpt and openpty).
reused by the enhached newbus locking once it is checked in.
This change can be easilly MFCed to STABLE_8 at the appropriate moment.
Reviewed by: jhb, scottl
Tested by: Giovanni Trematerra <giovanni dot trematerra at gmail dot com>
In the lockmgr support:
- GIANT_RESTORE() is just called when the sleep finishes, so the current
code can ends up into a giant unlock problem. Fix it by appropriately
call GIANT_RESTORE() when needed. Note that this is not exactly ideal
because for any interation of the adaptive spinning we drop and restore
Giant, but the overhead should be not a factor.
- In the lock held in exclusive mode case, after the adaptive spinning is
brought to completition, we should just retry to acquire the lock
instead to fallthrough. Fix that.
- Fix a style nit
In the sx support:
- Call GIANT_SAVE() before than looping. This saves some overhead because
in the current code GIANT_SAVE() is called several times.
Tested by: Giovanni Trematerra <giovanni dot trematerra at gmail dot com>
Remove the altkstacks, instead instantiate threads with kernel stack
allocated with the right size from the start. For the thread that has
kernel stack cached, verify that requested stack size is equial to the
actual, and reallocate the stack if sizes differ [1].
This fixes the bug introduced by r173361 that was committed several days
after r173004 and consisted of kthread_add(9) ignoring the non-default
kernel stack size.
Also, r173361 removed the caching of the kernel stacks for a non-first
thread in the process. Introduce separate kernel stack cache that keeps
some limited amount of preallocated kernel stacks to lower the latency
of thread allocation. Add vm_lowmem handler to prune the cache on
low memory condition. This way, system with reasonable amount of the
threads get lower latency of thread creation, while still not exhausting
significant portion of KVA for unused kstacks.
Submitted by: peter [1]
Discussed with: jhb, julian, peter
Reviewed by: jhb
Tested by: pho (and retested according to new test scenarious)
MFC after: 1 week
used by the suspension code, not greater then mnt_ref reference
counter value. Increment mnt_ref together with write counter
in vn_start_write()/ vn_start_secondary_write(), releasing in
vn_finished_write/vn_finished_secondary_write().
Since r186197, unmount code requires that no writers occured after all
references are expired. We still could get write counter incremented
for freed or reused struct mount, but it seems to be innocent, since
corresponding vnode should be referenced and reclaimed then.
Reported by: pho (last half a year), erwin
Reviewed by: attilio
Tested by: pho, erwin
MFC after: 1 week
correctly and do not match a colliding Debian GNU/kFreeBSD
brandinfo statements.
For this mark the Debian GNU/kFreeBSD brandinfo that it must have
an .note.ABI-tag section and ignore the old EI_OSABI brandinfo
when comparing a possibly colliding set of options.
Due to SYSINIT we add the brandinfo in a non-deterministic order,
so native FreeBSD is not always first. We may want to consider
to force native FreeBSD to come first as well.
The only way a problem could currently be noticed is when running an
i386 binary without the .note.ABI-tag on amd64 and the Debian GNU/kFreeBSD
brandinfo was matched first, as the fallback to ld-elf32.so.1 does
not exist in that case.
Reported and tested by: ticso
In collaboration with: kib
MFC after: 3 days
allocated with the right size from the start. For the thread that has
kernel stack cached, verify that requested stack size is equial to the
actual, and reallocate the stack if sizes differ [1].
This fixes the bug introduced by r173361 that was committed several days
after r173004 and consisted of kthread_add(9) ignoring the non-default
kernel stack size.
Also, r173361 removed the caching of the kernel stacks for a non-first
thread in the process. Introduce separate kernel stack cache that keeps
some limited amount of preallocated kernel stacks to lower the latency
of thread allocation. Add vm_lowmem handler to prune the cache on
low memory condition. This way, system with reasonable amount of the
threads get lower latency of thread creation, while still not exhausting
significant portion of KVA for unused kstacks.
Submitted by: peter [1]
Discussed with: jhb, julian, peter
Reviewed by: jhb
Tested by: pho
MFC after: 1 week
pages in an object.
- Add a new variant of d_mmap() currently called d_mmap2() which accepts
an additional in/out parameter that is the memory attribute to use for
the requested page.
- A driver either uses d_mmap() or d_mmap2() for all requests but not both.
The current implementation uses a flag in the cdevsw (D_MMAP2) to indicate
that the driver provides a d_mmap2() handler instead of d_mmap(). This
is done to make the change ABI compatible with existing drivers and
MFC'able to 7 and 8.
Submitted by: alc
MFC after: 1 month
causing a panic if it is killed due to a unsolved stack overflow
seen very late during shutdown on sparc64 when the gmirror worker
process exists, which is a regression introduced in 8.0.
Reviewed by: kib
MFC after: 3 days
This reverts part of r196460, so that sockets only return POLLHUP if both
directions are closed/error. Fifos get POLLHUP by closing the unused
direction immediately after creating the sockets.
The tools/regression/poll/*poll.c tests now pass except for two other things:
- if POLLHUP is returned, POLLIN is always returned as well instead of only
when there is data left in the buffer to be read
- fifo old/new reader distinction does not work the way POSIX specs it
Reviewed by: kib, bde
While usually not an issue, this firewalls bugs in the code that may
run us out of memory.
Fix a memory exhaustion in the case where devctl was disabled, but the
link was bouncing. The check to queue was in the wrong place.
Implement a new sysctl hw.bus.devctl_queue to control the depth. Make
compatibility hacks for hw.bus.devctl_disable to ease transition.
Reviewed by: emaste@
Approved by: re@ (kib)
MFC after: asap
Handle GNU/Linux according to LSB Core Specification 4.0,
Chapter 11. Object Format, 11.8. ABI note tag.
Also check the first word of desc, not only name, according to
glibc abi-tags specification to distinguish between Linux and
kFreeBSD.
Add explicit handling for Debian GNU/kFreeBSD, which runs
on our kernels as well [2].
In {amd64,i386}/trap.c, when checking osrel of the current process,
also check the ABI to not change the signal behaviour for Linux
binary processes, now that we save an osrel version for all three
from the lists above in struct proc [2].
These changes make it possible to run FreeBSD, Debian GNU/kFreeBSD
and Linux binaries on the same machine again for at least i386 and
amd64, and no longer break kFreeBSD which was detected as GNU(/Linux).
PR: kern/135468
Submitted by: dchagin [1] (initial patch)
Suggested by: kib [2]
Tested by: Petr Salinger (Petr.Salinger seznam.cz) for kFreeBSD
Reviewed by: kib
MFC after: 3 days
Say, a driver wants to have multiple console devices to pick from, you
would normally write down something like this:
CONSOLE_DRIVER(dev1);
CONSOLE_DRIVER(dev2);
Unfortunately, this means that you have to declare 10 cn routines,
instead of 5. It also isn't possible to initialize cn_arg on beforehand.
I noticed this restriction when I was implementing some of the console
bits for my vt(4) driver in my newcons branch. I have a single set of cn
routines (termcn_*) which are shared by all vt(4) console devices.
In order to solve this, I'm adding a separate consdev_ops structure,
which contains all the function pointers. This structure is referenced
through consdev's cn_ops field.
While there, I'm removing CONS_DRIVER() and cn_checkc, which have been
deprecated for years. They weren't used throughout the source, until the
Xen console driver showed up. CONSOLE_DRIVER() has been changed to do
the right thing. It now declares both the consdev and consdev_ops
structure and ties them together. In other words: this change doesn't
change the KPI for drivers that used the regular way of declaring
console devices.
If drivers want to use multiple console devices, they can do this as
follows:
static const struct consdev_ops mydriver_cnops = {
.cn_probe = mydriver_cnprobe,
...
};
static struct mydriver_softc cons0_softc = {
...
};
CONSOLE_DEVICE(cons0, mydriver_cnops, &cons0_softc);
static struct mydriver_softc cons1_softc = {
...
};
CONSOLE_DEVICE(cons1, mydriver_cnops, &cons1_softc);
Obtained from: //depot/user/ed/newcons/...
leaves behind an orphaned vnet. This change ensures that such vnets get
released.
This change affects only options VIMAGE builds.
Submitted by: jamie
Discussed with: bz
Approved by: re (rwatson), julian (mentor)
MFC after: 3 days
pf_proto_register(), iterate over all existing vnets to call protosw_init()
and thus the appropriate .pr_init() handler in the context of each vnet.
NB in the future we probably want to separate pr_init() handlers into
two, i.e. per-vnet and global, functions.
This change has no impact on nooptions VIMAGE builds.
Approved by: re (rwatson), julian (mentor)
MFC after: 3 days
several critical bugs, including race conditions and lock order issues:
Replace the single rwlock, ifnet_lock, with two locks, an rwlock and an
sxlock. Either can be held to stablize the lists and indexes, but both
are required to write. This allows the list to be held stable in both
network interrupt contexts and sleepable user threads across sleeping
memory allocations or device driver interactions. As before, writes to
the interface list must occur from sleepable contexts.
Reviewed by: bz, julian
MFC after: 3 days
Unfortunately, the wrappers that are present in pts(4) don't have the
mechanics to allow pty(4) to be unloaded safely, so I'm forcing this kld
to return EBUSY. This also means we have to enable some extra code in
pts(4) unconditionally.
Proposed by: rwatson
returning POLLHUP instead of POLLIN for several cases. Now, the
tools/regression/poll results for FreeBSD are closer to that of the
Solaris and Linux.
Also, improve the POSIX conformance by explicitely clearing POLLOUT
when POLLHUP is reported in pollscan(), making the fix global.
Submitted by: bde
Reviewed by: rwatson
MFC after: 1 week
I noticed several drivers in our tree don't actually care about parity
and framing, such as pts(4), snp(4) (and my partially finished console
driver). Instead of duplicating a lot of code, I think we'd better add a
utility function for those drivers to quickly process a buffer of input.
Also change pts(4) and snp(4) to use this function.
better semantics if a request to append an address range to an existing list
fails.
- When cloning an sglist, properly set the length in the new sglist instead of
leaving the new list empty.
- Properly compute the amount of data added to an sglist via
_sglist_append_buf(). This allows sglist_consume_uio() to properly update
uio_resid.
- When a request to append an address range to a scatter/gather list fails,
restore the sglist to the state it had at the start of the function call
instead of resetting it to an empty list.
Requested by: np (3)
Approved by: re (kib)
- Only print the warning once, instead of filling up the screen.
- Use the word "legacy" for the pty_warningcnt description, to prevent
confusion.
- Use log() instead of printf().
Discussed with: rwatson, jhb
Approved by: re (kib)
a pointer-fetching specific operation check. Consequently, rename the
operation ASSERT_ATOMIC_LOAD_PTR().
* Fix the implementation of ASSERT_ATOMIC_LOAD_PTR() by checking
directly alignment on the word boundry, for all the given specific
architectures. That's a bit too strict for some common case, but it
assures safety.
* Add a comment explaining the scope of the macro
* Add a new stub in the lockmgr specific implementation
Tested by: marcel (initial version), marius
Reviewed by: rwatson, jhb (comment specific review)
Approved by: re (kib)
replace it with wrappers around our taskqueue(9).
To make it possible implement taskqueue_member() function which returns 1
if the given thread was created by the given taskqueue.
Approved by: re (kib)
the kern.polling.enable sysctl, remove the sysctl. It has been deprecated
since FreeBSD 6 in favour of per-ifnet polling flags.
Reviewed by: luigi
Approved by: re (kib)
Check that the given variable is at most uintptr_t in size and that
it is aligned.
Note: ASSERT_ATOMIC_LOAD() uses ALIGN() to check for adequate
alignment -- however, the function of ALIGN() is to guarantee
alignment, and therefore may lead to stronger alignment
enforcement than necessary for types that are smaller than
sizeof(uintptr_t).
Add checks to mtx, rw and sx locks init functions to detect possible
breakage. This was used during debugging of the problem fixed with
r196118 where a pointer was on an un-aligned address in the dpcpu area.
In collaboration with: rwatson
Reviewed by: rwatson
Approved by: re (kib)
has proven to have a good effect when entering KDB by using a NMI,
but it completely violates all the good rules about interrupts
disabled while holding a spinlock in other occasions. This can be the
cause of deadlocks on events where a normal IPI_STOP is expected.
* Adds an new IPI called IPI_STOP_HARD on all the supported architectures.
This IPI is responsible for sending a stop message among CPUs using a
privileged channel when disponible. In other cases it just does match a
normal IPI_STOP.
Right now the IPI_STOP_HARD functionality uses a NMI on ia32 and amd64
architectures, while on the other has a normal IPI_STOP effect. It is
responsibility of maintainers to eventually implement an hard stop
when necessary and possible.
* Use the new IPI facility in order to implement a new userend SMP kernel
function called stop_cpus_hard(). That is specular to stop_cpu() but
it does use the privileged channel for the stopping facility.
* Let KDB use the newly introduced function stop_cpus_hard() and leave
stop_cpus() for all the other cases
* Disable interrupts on CPU0 when starting the process of APs suspension.
* Style cleanup and comments adding
This patch should fix the reboot/shutdown deadlocks many users are
constantly reporting on mailing lists.
Please don't forget to update your config file with the STOP_NMI
option removal
Reviewed by: jhb
Tested by: pho, bz, rink
Approved by: re (kib)
with their own virtual network stack. Jails only inheriting a
network stack cannot change anything that cannot be changed from
within a prison.
Reviewed by: rwatson, zec
Approved by: re (kib)
While show pcpu prints pc_dynamic this also prints the original
memory address as well as the maths.
Once dpcpu goes NUMA this is considered to help debugging as well.
Reviewed by: rwatson
Approved by: re
The newbus lock is responsible for protecting newbus internIal structures,
device states and devclass flags. It is necessary to hold it when all
such datas are accessed. For the other operations, softc locking should
ensure enough protection to avoid races.
Newbus lock is automatically held when virtual operations on the device
and bus are invoked when loading the driver or when the suspend/resume
take place. For other 'spourious' operations trying to access/modify
the newbus topology, newbus lock needs to be automatically acquired and
dropped.
For the moment Giant is also acquired in some key point (modules subsystem)
in order to avoid problems before the 8.0 release as module handlers could
make assumptions about it. This Giant locking should go just after
the release happens.
Please keep in mind that the public interface can be expanded in order
to provide more support, if there are really necessities at some point
and also some bugs could arise as long as the patch needs a bit of
further testing.
Bump __FreeBSD_version in order to reflect the newbus lock introduction.
Reviewed by: ed, hps, jhb, imp, mav, scottl
No answer by: ariff, thompsa, yongari
Tested by: pho,
G. Trematerra <giovanni dot trematerra at gmail dot com>,
Brandon Gooch <jamesbrandongooch at gmail dot com>
Sponsored by: Yahoo! Incorporated
Approved by: re (ksmith)
- fix write() on pseudo-terminal masters to return the amount of bytes
passed to the TTY, not the amount of bytes read from user.
- fix ttydisc_rint_bypass() to set the high watermark when it cannot
write all input, just like ttydisc_rint() itself.
Approved by: re (kib)
vnet.h, we now use jails (rather than vimages) as the abstraction
for virtualization management, and what remained was specific to
virtual network stacks. Minor cleanups are done in the process,
and comments updated to reflect these changes.
Reviewed by: bz
Approved by: re (vimage blanket)
instead of whatever the parent/system has (which is generally 0). This
mirrors the old-style default used for jail(2) in conjunction with the
security.jail.enforce_statfs sysctl.
Approved by: re (kib), bz (mentor)
- Don't grab the filedesc lock just to read fd_cmask.
- Drop vnode locks earlier when mounting the root filesystem and before
sanitizing stdin/out/err file descriptors during execve().
Submitted by: kib
Approved by: re (rwatson)
MFC after: 1 week
in prison_equal_ip4/6 while an inp mutex was held. Locking allprison_lock
can be avoided by making a restriction on the IP addresses associated with
jails:
Don't allow the "ip4" and "ip6" parameters to be changed after a jail is
created. Setting the "ip4.addr" and "ip6.addr" parameters is allowed,
but only if the jail was already created with either ip4/6=new or
ip4/6=disable. With this restriction, the prison flags in question
(PR_IP4_USER and PR_IP6_USER) become read-only and can be checked
without locking.
This also allows the simplification of a messy code path that was needed
to handle an existing prison gaining an IP address list.
PR: kern/136899
Reported by: Dirk Meyer
Approved by: re (kib), bz (mentor)
jails have their own IP stack and don't have access to the parent IP
addresses anyway. Note that a virtual network stack forms a break
between prisons with regard to the list of allowed IP addresses.
Approved by: re (kib), bz (mentor)
"disable", which only allows access to the parent/physical system's
IP addresses when specifically directed. Change the default value of
"host" to "new", and don't copy the parent host values, to insulate
jails from the parent hostname et al.
Approved by: re (kib), bz (mentor)
provide specific macros, AUDIT_ARG_UPATH1() and AUDIT_ARG_UPATH2()
to capture path information for audit records. This allows us to
move the definitions of ARG_* out of the public audit header file,
as they are an implementation detail of our current kernel-internal
audit record, which may change.
Approved by: re (kensmith)
Obtained from: TrustedBSD Project
MFC after: 1 month
to avoid exposing ARG_ macros/flag values outside of the audit code in
order to name which one of two possible vnodes will be audited for a
system call.
Approved by: re (kib)
Obtained from: TrustedBSD Project
MFC after: 1 month
instead of the root/current working directory as the starting point for
lookups. Up to two such descriptors can be audited. Add audit record
BSM encoding for fooat(2).
Note: due to an error in the OpenBSM 1.1p1 configuration file, a
further change is required to that file in order to fix openat(2)
auditing.
Approved by: re (kib)
Reviewed by: rdivacky (fooat(2) portions)
Obtained from: TrustedBSD Project
MFC after: 1 month
(ifconfig ifN (-)vnet <jname|jid>) work correctly.
Move vi_if_move to if.c and split it up into two functions(*),
one for each ioctl.
In the reclaim case, correctly set the vnet before calling if_vmove.
Instead of silently allowing a move of an interface from the current
vnet to the current vnet, return an error. (*)
There is some duplicate interface name checking before actually moving
the interface between network stacks without locking and thus race
prone. Ideally if_vmove will correctly and automagically handle these
in the future.
Suggested by: rwatson (*)
Approved by: re (kib)
restrictions) were found to be inadequately described by a boolean.
Define a new parameter type with three values (disable, new, inherit)
to handle these and future cases.
Approved by: re (kib), bz (mentor)
Discussed with: rwatson
ability to retrieve the group list of each process.
Modify procstat's -s option to query this mib when the kinfo_proc
reports that the field has been truncated. If the mib does not exist,
fall back to the truncated list.
Reviewed by: rwatson
Approved by: re (kib)
MFC after: 2 weeks
in up to 16 (KI_NGROUPS) values and steal a bit from ki_cr_flags
(all bits currently unused) to indicate overflow with the new flag
KI_CRF_GRP_OVERFLOW.
This fixes procstat -s.
Approved by: re (kib)
a device pager (OBJT_DEVICE) object in that it uses fictitious pages to
provide aliases to other memory addresses. The primary difference is that
it uses an sglist(9) to determine the physical addresses for a given offset
into the object instead of invoking the d_mmap() method in a device driver.
Reviewed by: alc
Approved by: re (kensmith)
MFC after: 2 weeks
network stacks, VNET_SYSINIT:
- Add VNET_SYSINIT and VNET_SYSUNINIT macros to declare events that will
occur each time a network stack is instantiated and destroyed. In the
!VIMAGE case, these are simply mapped into regular SYSINIT/SYSUNINIT.
For the VIMAGE case, we instead use SYSINIT's to track their order and
properties on registration, using them for each vnet when created/
destroyed, or immediately on module load for already-started vnets.
- Remove vnet_modinfo mechanism that existed to serve this purpose
previously, as well as its dependency scheme: we now just use the
SYSINIT ordering scheme.
- Implement VNET_DOMAIN_SET() to allow protocol domains to declare that
they want init functions to be called for each virtual network stack
rather than just once at boot, compiling down to DOMAIN_SET() in the
non-VIMAGE case.
- Walk all virtualized kernel subsystems and make use of these instead
of modinfo or DOMAIN_SET() for init/uninit events. In some cases,
convert modular components from using modevent to using sysinit (where
appropriate). In some cases, do minor rejuggling of SYSINIT ordering
to make room for or better manage events.
Portions submitted by: jhb (VNET_SYSINIT), bz (cleanup)
Discussed with: jhb, bz, julian, zec
Reviewed by: bz
Approved by: re (VIMAGE blanket)
non-vrtiualized sysctls so we cannot used one common function.
Add a macro to convert the arg1 in the virtualized case to
vnet.h to not expose the maths to all over the code.
Add a wrapper for the single virtualized call, properly handling
arg1 and call the default implementation from there.
Convert the two over places to use the new macro.
Reviewed by: rwatson
Approved by: re (kib)
portion of the page that was written. Among other problems, this
page might be picked up by pagedaemon, with failed assertion in
vm_pageout_flush() about validity of the page.
Reported and tested by: pho
Approved by: re (kensmith)
MFC after: 3 weeks
unused custom mutex/condvar-based sleep locks with two locks: an
rwlock (for non-sleeping use) and sxlock (for sleeping use). Either
acquired for read is sufficient to stabilize the vnet list, but both
must be acquired for write to modify the list.
Replace previous no-op read locking macros, used in various places
in the stack, with actual locking to prevent race conditions. Callers
must declare when they may perform unbounded sleeps or not when
selecting how to lock.
Refactor vnet sysinits so that the vnet list and locks are initialized
before kernel modules are linked, as the kernel linker will use them
for modules loaded by the boot loader.
Update various consumers of these KPIs based on whether they may sleep
or not.
Reviewed by: bz
Approved by: re (kib)
modules was present, which turns out to be false in some situations.
Back out the assertion.
Reported by: Luiz Otavio O Souza <lists.br at gmail.com>,
Florian Smeets <flo at kasimir.com>
Approved by: re (kensmith) (implicit)
PCATCH, to indicate that thread shall not be stopped upon receipt of
SIGSTOP until it reaches the kernel->usermode boundary.
Also change thread_single(SINGLE_NO_EXIT) to only stop threads at
the user boundary unconditionally.
Tested by: pho
Reviewed by: jhb
Approved by: re (kensmith)
process that still need to be suspended or exited from thread_single
into the new function calc_remaining().
Tested by: pho
Reviewed by: jhb
Approved by: re (kensmith)
(DPCPU), as suggested by Peter Wemm, and implement a new per-virtual
network stack memory allocator. Modify vnet to use the allocator
instead of monolithic global container structures (vinet, ...). This
change solves many binary compatibility problems associated with
VIMAGE, and restores ELF symbols for virtualized global variables.
Each virtualized global variable exists as a "reference copy", and also
once per virtual network stack. Virtualized global variables are
tagged at compile-time, placing the in a special linker set, which is
loaded into a contiguous region of kernel memory. Virtualized global
variables in the base kernel are linked as normal, but those in modules
are copied and relocated to a reserved portion of the kernel's vnet
region with the help of a the kernel linker.
Virtualized global variables exist in per-vnet memory set up when the
network stack instance is created, and are initialized statically from
the reference copy. Run-time access occurs via an accessor macro, which
converts from the current vnet and requested symbol to a per-vnet
address. When "options VIMAGE" is not compiled into the kernel, normal
global ELF symbols will be used instead and indirection is avoided.
This change restores static initialization for network stack global
variables, restores support for non-global symbols and types, eliminates
the need for many subsystem constructors, eliminates large per-subsystem
structures that caused many binary compatibility issues both for
monitoring applications (netstat) and kernel modules, removes the
per-function INIT_VNET_*() macros throughout the stack, eliminates the
need for vnet_symmap ksym(2) munging, and eliminates duplicate
definitions of virtualized globals under VIMAGE_GLOBALS.
Bump __FreeBSD_version and update UPDATING.
Portions submitted by: bz
Reviewed by: bz, zec
Discussed with: gnn, jamie, jeff, jhb, julian, sam
Suggested by: peter
Approved by: re (kensmith)
dependent memory attributes:
Rename vm_cache_mode_t to vm_memattr_t. The new name reflects the
fact that there are machine-dependent memory attributes that have
nothing to do with controlling the cache's behavior.
Introduce vm_object_set_memattr() for setting the default memory
attributes that will be given to an object's pages.
Introduce and use pmap_page_{get,set}_memattr() for getting and
setting a page's machine-dependent memory attributes. Add full
support for these functions on amd64 and i386 and stubs for them on
the other architectures. The function pmap_page_set_memattr() is also
responsible for any other machine-dependent aspects of changing a
page's memory attributes, such as flushing the cache or updating the
direct map. The uses include kmem_alloc_contig(), vm_page_alloc(),
and the device pager:
kmem_alloc_contig() can now be used to allocate kernel memory with
non-default memory attributes on amd64 and i386.
vm_page_alloc() and the device pager will set the memory attributes
for the real or fictitious page according to the object's default
memory attributes.
Update the various pmap functions on amd64 and i386 that map pages to
incorporate each page's memory attributes in the mapping.
Notes: (1) Inherent to this design are safety features that prevent
the specification of inconsistent memory attributes by different
mappings on amd64 and i386. In addition, the device pager provides a
warning when a device driver creates a fictitious page with memory
attributes that are inconsistent with the real page that the
fictitious page is an alias for. (2) Storing the machine-dependent
memory attributes for amd64 and i386 as a dedicated "int" in "struct
md_page" represents a compromise between space efficiency and the ease
of MFCing these changes to RELENG_7.
In collaboration with: jhb
Approved by: re (kib)
correctly checks for reclaimed vnode, possibly calling VOP_REVOKE for
such vnode. If the terminal is already revoked, or devfs mount was
forcibly unmounted, the revocation of doomed ctty vnode causes panic.
Reported and tested by: lstewart
Approved by: re (kensmith)
MFC after: 2 weeks
if the new file mode is the same as it was before; however, this
optimization must be disabled for filesystems that support NFSv4 ACLs.
Chmod uses pathconf(2) to determine whether this is the case - however,
pathconf(2) always follows symbolic links, while the 'chmod -h' doesn't.
This change adds lpathconf(3) to make it possible to solve that problem
in a clean way.
Reviewed by: rwatson (earlier version)
Approved by: re (kib)
As pointed out, POLLHUP should be generated, even if it hasn't been
specified on input. It is also not allowed to return both POLLOUT and
POLLHUP at the same time.
Reported by: jilles
Approved by: re (kib)
under VM environments, it's too slow for FreeBSD to work
properly. For example, ping at 10hz pings about every 600ms
instead of about every second.
Approved by: re (kib)
when all writers, observed by reader, exited. Use writer generation
counter for fifo, and store the snapshot of the fifo generation in the
f_seqcount field of struct file, that is otherwise unused for fifos.
Set FreeBSD-undocumented POLLINIGNEOF flag only when file f_seqcount is
equal to fifo' fi_wgen, and revert r89376.
Fix POLLINIGNEOF for sockets and pipes, and return POLLHUP for them.
Note that the patch does not fix not returning POLLHUP for fifos.
PR: kern/94772
Submitted by: bde (original version)
Reviewed by: rwatson, jilles
Approved by: re (kensmith)
MFC after: 6 weeks (might be)
around the sequence that drop vnode lock and then busies the mount point.
Not having vlocked node or direct reference to the mp allows for the
forced unmount to proceed, making mp unmounted or reused.
Tested by: pho
Reviewed by: jeff
Approved by: re (kensmith)
MFC after: 2 weeks
system calls:
- Centralize generation of argument tokens for VM addresses in a macro,
ADDR_TOKEN(), and properly encode 64-bit addresses in 64-bit arguments.
- Fix up argument numbers across a large number of syscalls so that they
match the numeric argument into the system call.
- Don't audit the address argument to ioctl(2) or ptrace(2), but do keep
generating tokens for mmap(2), minherit(2), since they relate to passing
object access across execve(2).
Approved by: re (audit argument blanket)
Obtained from: TrustedBSD Project
MFC after: 1 week
using the size of the descriptor array.
- A lock is not needed to fetch fd_lastfile. The results are stale the
instant it is dropped.
- Use a private mutex pool for select since the pool mutex is not used
as a leaf.
- Fetch the si_mtx pointer first before resorting to hashing to compute
the mutex address.
Reviewed by: McKusick
Approved by: re (kib)
- For x86, change the interrupt source method to assign an interrupt source
to a specific CPU to return an error value instead of void, thus allowing
it to fail.
- If moving an interrupt to a CPU fails due to a lack of IDT vectors in the
destination CPU, fail the request with ENOSPC rather than panicing.
- For MSI interrupts on x86 (but not MSI-X), only allow cpuset to be used
on the first interrupt in a group. Moving the first interrupt in a group
moves the entire group.
- Use the icu_lock to protect intr_next_cpu() on x86 instead of the
intr_table_lock to fix a LOR introduced in the last set of MSI changes.
- Add a new privilege PRIV_SCHED_CPUSET_INTR for using cpuset with
interrupts. Previously, binding an interrupt to a CPU only performed a
privilege check if the interrupt had an interrupt thread. Interrupts
without a thread could be bound by non-root users as a result.
- If an interrupt event's assign_cpu method fails, then restore the original
cpuset mask for the associated interrupt thread.
Approved by: re (kib)
rather than as paths, which would lead to them being treated as relative
pathnames and hence confusingly converted into absolute pathnames.
Capture flags to unmount(2) via an argument token.
Approved by: re (audit argument blanket)
MFC after: 3 days
easily determine how much space is left in the send queue; they do not
need to know the send queue size.
NetBSD revisions:
sys_socket.c r1.41, 1.42
filio.h r1.9
Obtained from: NetBSD
Approved by: re (kensmith)
loading hwpmc, but calculate at runtime and allocate the necessary space.
Also the current logic is wrong as it can lead to an endless loop.
Sponsored by: Sandvine Incorporated
Reported by: Ryan Stone <rstone at sandvine dot com>
Tested by: Giovanni Trematerra
<giovanni dot trematerra at gmail dot com>
Approved by: re (kib)
Introduce the new flag KNF_NOKQLOCK to allow event callers to be called
without KQ_LOCK mtx held.
- Modify VFS knote calls to always use KNF_NOKQLOCK flag. This is required
for ZFS as its getattr implementation may sleep.
Approved by: re (rwatson)
Reviewed by: kib
MFC after: 2 weeks
inbound data waiting on a filedescriptor, such as a pipe or a socket,
for instance by using select(2), poll(2), kqueue(2), ioctl(FIONREAD)
etc.
But we have no way of finding out if written data have yet to be
disposed of, for instance, transmitted (and ack'ed!) to some remote
host, or read by the applicantion at the far end of the pipe.
The closest we get, is calling shutdown(2) on a TCP socket in
non-blocking mode, but this has the undesirable sideeffect of
preventing future communication.
Add a complement to FIONREAD, called FIONWRITE, which returns the
number of bytes not yet properly disposed of. Implement it for
all sockets.
Background:
A HTTP server will want to time out connections, if no new request
arrives within a certain period after the last transmitted response
has actually been sent (and ack'ed).
For a busy HTTP server, this timeout can be subsecond duration.
In order to signal to a load-balancer that the connection is truly
dead, TCP_RST will be the preferred method, as this avoids the need
for a RTT delay for FIN handshaking, with a client which, surprisingly
often, no longer at the remote IP number.
If a slow, distant client is being served a response which is big
enough to fill the window, but small enough to fit in the socket
buffer, the write(2) call will return immediately.
If the session timeout is armed at that time, all bytes in the
response may not have been transmitted by the time it fires.
FIONWRITE allows the timeout to check that no data is outstanding
on the connection, before it TCP_RST's it.
Input & Idea from: rwatson
Approved by: re (kib)
in the case of a file system with a block size that is less than the page
size, cluster_rbuild() looks at too many of the page's valid bits.
Consequently, it may terminate prematurely, resulting in poor performance.
Reported by: bde
Reviewed by: tegge
Approved by: re (kib)
specific macros for each audit argument type. This makes it easier to
follow call-graphs, especially for automated analysis tools (such as
fxr).
In MFC, we should leave the existing AUDIT_ARG() macros as they may be
used by third-party kernel modules.
Suggested by: brooks
Approved by: re (kib)
Obtained from: TrustedBSD Project
MFC after: 1 week
required by video card drivers. Specifically, this change introduces
vm_cache_mode_t with an appropriate VM_CACHE_DEFAULT definition on all
architectures. In addition, this changes adds a vm_cache_mode_t parameter
to kmem_alloc_contig() and vm_phys_alloc_contig(). These will be the
interfaces for allocating mapped kernel memory and physical memory,
respectively, with non-default cache modes.
In collaboration with: jhb
Specifically, if a non-root user attempts to bind an interrupt the request
will now report failure with EPERM rather than silently failing with a
successful return code.
MFC after: 1 week
offset of the stat is not known until link time so we must emit a
function to call SYSCTL_ADD_PROC rather than using SYSCTL_PROC
directly.
- Eliminate the atomic from SCHED_STAT_INC now that it's using per-cpu
variables. Sched stats are always incremented while we're holding
a spinlock so no further protection is required.
Reviewed by: sam
additional privileges as well as not restricting the type of
sockets a user can open.
Note: the VIMAGE/vnet fetaure of of jails is still considered
experimental and cannot guarantee that privileged users
can be kept imprisoned if enabled.
Reviewed by: rwatson
Approved by: bz (mentor)
- The uid/cuid members of struct ipc_perm are now uid_t instead of unsigned
short.
- The gid/cgid members of struct ipc_perm are now gid_t instead of unsigned
short.
- The mode member of struct ipc_perm is now mode_t instead of unsigned short
(this is merely a style bug).
- The rather dubious padding fields for ABI compat with SV/I386 have been
removed from struct msqid_ds and struct semid_ds.
- The shm_segsz member of struct shmid_ds is now a size_t instead of an
int. This removes the need for the shm_bsegsz member in struct
shmid_kernel and should allow for complete support of SYSV SHM regions
>= 2GB.
- The shm_nattch member of struct shmid_ds is now an int instead of a
short.
- The shm_internal member of struct shmid_ds is now gone. The internal
VM object pointer for SHM regions has been moved into struct
shmid_kernel.
- The existing __semctl(), msgctl(), and shmctl() system call entries are
now marked COMPAT7 and new versions of those system calls which support
the new ABI are now present.
- The new system calls are assigned to the FBSD-1.1 version in libc. The
FBSD-1.0 symbols in libc now refer to the old COMPAT7 system calls.
- A simplistic framework for tagging system calls with compatibility
symbol versions has been added to libc. Version tags are added to
system calls by adding an appropriate __sym_compat() entry to
src/lib/libc/incldue/compat.h. [1]
PR: kern/16195 kern/113218 bin/129855
Reviewed by: arch@, rwatson
Discussed with: kan, kib [1]
them under COMPAT_FREEBSD[4567]. Starting with FreeBSD 5.0 the SYSV IPC
API was implemented via direct system calls (e.g. msgctl(), msgget(), etc.)
rather than indirecting through the var-args *sys() system calls. The
shmsys() system call was already effectively deprecated for all but
COMPAT_FREEBSD4 already as its implementation for the !COMPAT_FREEBSD4 case
was to simply invoke nosys().
- Modules and kernel code alike may use DPCPU_DEFINE(),
DPCPU_GET(), DPCPU_SET(), etc. akin to the statically defined
PCPU_*. Requires only one extra instruction more than PCPU_* and is
virtually the same as __thread for builtin and much faster for shared
objects. DPCPU variables can be initialized when defined.
- Modules are supported by relocating the module's per-cpu linker set
over space reserved in the kernel. Modules may fail to load if there
is insufficient space available.
- Track space available for modules with a one-off extent allocator.
Free may block for memory to allocate space for an extent.
Reviewed by: jhb, rwatson, kan, sam, grehan, marius, marcel, stas
The advantage of using a separate condvar is that we can just use
cv_signal(9) instead of cv_broadcast(9). It makes no sense to wake up
multiple threads. It also makes the TTY code easier to understand.
t_dcdwait sounds totally unrelated.
I suspect the usage of bgwait causes a lot of spurious wakeups when
threads are blocked in the background, because they will be woken up
each time a write() call is performed.
Also wakeup dcdwait when the TTY is abandoned.
rlimit RLIMIT_SWAP that limits the amount of swap that may be reserved
for the uid.
The accounting information (charge) is associated with either map entry,
or vm object backing the entry, assuming the object is the first one
in the shadow chain and entry does not require COW. Charge is moved
from entry to object on allocation of the object, e.g. during the mmap,
assuming the object is allocated, or on the first page fault on the
entry. It moves back to the entry on forks due to COW setup.
The per-entry granularity of accounting makes the charge process fair
for processes that change uid during lifetime, and decrements charge
for proper uid when region is unmapped.
The interface of vm_pager_allocate(9) is extended by adding struct ucred *,
that is used to charge appropriate uid when allocation if performed by
kernel, e.g. md(4).
Several syscalls, among them is fork(2), may now return ENOMEM when
global or per-uid limits are enforced.
In collaboration with: pho
Reviewed by: alc
Approved by: re (kensmith)
stream (TCP) sockets.
It is functionally identical to generic soreceive() but has a
number stream specific optimizations:
o does only one sockbuf unlock/lock per receive independent of
the length of data to be moved into the uio compared to
soreceive() which unlocks/locks per *mbuf*.
o uses m_mbuftouio() instead of its own copy(out) variant.
o much more compact code flow as a large number of special
cases is removed.
o much improved reability.
It offers significantly reduced CPU usage and lock contention
when receiving fast TCP streams. Additional gains are obtained
when the receiving application is using SO_RCVLOWAT to batch up
some data before a read (and wakeup) is done.
This function was written by "reverse engineering" and is not
just a stripped down variant of soreceive().
It is not yet enabled by default on TCP sockets. Instead it is
commented out in the protocol initialization in tcp_usrreq.c
until more widespread testing has been done.
Testers, especially with 10GigE gear, are welcome.
MFP4: r164817 //depot/user/andre/soreceive_stream/
long mbuf chain into an arbitrary large uio in a single step.
It is a functional mirror image of m_uiotombuf().
This function is supposed to be used instead of hand rolled code
with the same purpose and to concentrate it into one place for
potential further optimization or hardware assistance.
chains) to pure data mbufs using m_demote(). This removes the
packet header and all m_tag information as they are not meaningful
anymore on a stream socket where mbufs are linked through m->m_next.
Strictly speaking a packet header can be only ever valid on the first
mbuf in an m_next chain.
sbcompress() was doing this already when the mbuf chain layout lent
itself to it (e.g. header splitting or merge-append), just not
consistently.
This frees resources at socket buffer append time instead of at
sbdrop_internal() time after data has been read from the socket.
For MAC the per packet information has done its duty and during
socket buffer appending the policy of the socket itself takes over.
With the append the packet boundaries disappear naturally and with
it any context that was based on it. None of the residual information
from mbuf headers in the socket buffer on stream sockets was looked at.
- remove HT_HEADER test (MT_HEADER == MT_DATA for some time now)
- be more pedantic about m_nextpkt in other than first mbuf
- update m_flags to be retained
vn_open_cred in default implementation. Valid struct ucred is needed for
audit and MAC, and curthread credentials may be wrong.
This further requires modifying the interface of vn_fullpath(9), but it
is out of scope of this change.
Reviewed by: rwatson
vn_open_cred invocations shall not audit namei path.
In particular, specify VN_OPEN_NOAUDIT for dotdot lookup performed by
default implementation of vop_vptocnp, and for the open done for core
file. vn_fullpath is called from the audit code, and vn_open there need
to disable audit to avoid infinite recursion. Core file is created on
return to user mode, that, in particular, happens during syscall return.
The creation of the core file is audited by direct calls, and we do not
want to overwrite audit information for syscall.
Reported, reviewed and tested by: rwatson
Now that we start to use credentials on character devices more often
(because of MPSAFE TTY), move the prison-checks that are in place in the
TTY code into devfs.
Instead of strictly comparing the prisons, use the more common
prison_check() function to compare credentials. This means that
pseudo-terminals are only visible in devfs by processes within the same
jail and parent jails.
Even though regular users in parent jails can now interact with
pseudo-terminals from child jails, this seems to be the right approach.
These processes are also capable of interacting with the jailed
processes anyway, through signals for example.
Reviewed by: kib, rwatson (older version)
NGROUPS_MAX, eliminate ABI dependencies on them, and raise the to 1024
and 1023 respectively. (Previously they were equal, but under a close
reading of POSIX, NGROUPS_MAX was defined to be too large by 1 since it
is the number of supplemental groups, not total number of groups.)
The bulk of the change consists of converting the struct ucred member
cr_groups from a static array to a pointer. Do the equivalent in
kinfo_proc.
Introduce new interfaces crcopysafe() and crsetgroups() for duplicating
a process credential before modifying it and for setting group lists
respectively. Both interfaces take care for the details of allocating
groups array. crsetgroups() takes care of truncating the group list
to the current maximum (NGROUPS) if necessary. In the future,
crsetgroups() may be responsible for insuring invariants such as sorting
the supplemental groups to allow groupmember() to be implemented as a
binary search.
Because we can not change struct xucred without breaking application
ABIs, we leave it alone and introduce a new XU_NGROUPS value which is
always 16 and is to be used or NGRPS as appropriate for things such as
NFS which need to use no more than 16 groups. When feasible, truncate
the group list rather than generating an error.
Minor changes:
- Reduce the number of hand rolled versions of groupmember().
- Do not assign to both cr_gid and cr_groups[0].
- Modify ipfw to cache ucreds instead of part of their contents since
they are immutable once referenced by more than one entity.
Submitted by: Isilon Systems (initial implementation)
X-MFC after: never
PR: bin/113398 kern/133867
Instead of locking the local unp followed by the remote unp, use the same
locking model as accept() and read lock the global link lock followed by
the remote unp while fetching the remote sockaddr.
Reported by: Mel Flynn mel.flynn of mailing.thruhere.net
Reviewed by: rwatson
MFC after: 1 week
allocator for the jumbo frames zones. This change has two benefits: (1) a
custom back-end deallocator is no longer required. UMA's standard
deallocator suffices. (2) It eliminates a potentially confusing artifact
of using contigmalloc(): The malloc(9) statistics contain bogus information
about the usage of jumbo frames. Specifically, the malloc(9) statistics
report all jumbo frames in use whereas the UMA zone statistics report the
"truth" about the number in use vs. the number free.
in the type field of system call tables. Specifically, one can now use
the 'NO*' types as flags in addition to the 'COMPAT*' types. For example,
to tag 'COMPAT*' system calls as living in a KLD via NOSTD. The COMPAT*
type is required to be listed first in this case.
- Add new functions 'type()' and 'flag()' to the embedded awk script in
makesyscalls.sh that return true if a requested flag is found in the
type field ($3). The flag() function checks all of the flags in the
field, but type() only checks the first flag. type() is meant to be
used in the top-level "switch" statement and flag() should be used
otherwise.
- Retire the CPT_NOA type, it is now replaced with "COMPAT|NOARGS" using
the flags approach.
- Tweak the comment descriptions of COMPAT[46] system calls so that they
say "freebsd[46] foo" rather than "old foo".
- Document the COMPAT6 type.
- Sync comments in compat32 syscall table with the master table.
- Mark nfsclnt as UNIMPL. It should have been NOSTD instead of NOIMPL back
when it lived in nfsclient.ko, but it was removed from that a long time
ago.
Actually, as it did receive few tuning, the support is disabled by
default, but it can opt-in with the option ADAPTIVE_LOCKMGRS.
Due to the nature of lockmgrs, adaptive spinning needs to be
selectively enabled for any interested lockmgr.
The support is bi-directional, or, in other ways, it will work in both
cases if the lock is held in read or write way. In particular, the
read path is passible of further tunning using the sysctls
debug.lockmgr.retries and debug.lockmgr.loops . Ideally, such sysctls
should be axed or compiled out before release.
Addictionally note that adaptive spinning doesn't cope well with
LK_SLEEPFAIL. The reason is that many (and probabilly all) consumers
of LK_SLEEPFAIL are mainly interested in knowing if the interlock was
dropped or not in order to reacquire it and re-test initial conditions.
This directly interacts with adaptive spinning because lockmgr needs
to drop the interlock while spinning in order to avoid a deadlock
(further details in the comments inside the patch).
Final note: finding someone willing to help on tuning this with
relevant workloads would be either very important and appreciated.
Tested by: jeff, pho
Requested by: many
The code that was in place in exit1() was mainly based on code from the
old TTY layer. The main reason behind this, was because at one moment I
ran a system that had two TTY layers in place at the same time. It is
now sufficient to do the following:
- Remove references from the session structure to the TTY vnode and the
session leader.
- If we have a controlling TTY and the session used by the TTY is equal
to our session, send the SIGHUP.
- If we have a vnode to the controlling TTY which has not been revoked,
revoke it.
While there, change sys/kern/tty.c to use s_ttyp in the comparison
instead of s_ttyvp. It should not make any difference, because s_ttyvp
can only become null when the session leader already left, but it's
nicer to compare against the proper value.
any open file descriptors >= 'lowfd'. It is largely identical to the same
function on other operating systems such as Solaris, DFly, NetBSD, and
OpenBSD. One difference from other *BSD is that this closefrom() does not
fail with any errors. In practice, while the manpages for NetBSD and
OpenBSD claim that they return EINTR, they ignore internal errors from
close() and never return EINTR. DFly does return EINTR, but for the common
use case (closing fd's prior to execve()), the caller really wants all
fd's closed and returning EINTR just forces callers to call closefrom() in
a loop until it stops failing.
Note that this implementation of closefrom(2) does not make any effort to
resolve userland races with open(2) in other threads. As such, it is not
multithread safe.
Submitted by: rwatson (initial version)
Reviewed by: rwatson
MFC after: 2 weeks
Right now the only way to make tcsetsid(3)/TIOCSCTTY work, is by
ensuring the session leader is dead. This means that an application that
catches SIGHUPs and performs a sleep prevents us from assigning a new
session leader.
Change the code to make it work on revoked TTYs as well. This allows us
to change init(8) to make the shutdown script run in a more clean
environment.
parameter "vnet" when it is created, a new vnet instance will be created
along with the jail. Networks interfaces can be moved between prisons
with an ioctl similar to the one that moves them between vimages.
For now vnets will co-exist under both jails and vimages, but soon
struct vimage will be going away.
Reviewed by: zec, julian
Approved by: bz (mentor)
There is an external use in the opensolaris code.
I am not sure how this ever worked but I have seen two reports of:
link_elf: symbol hardlink_check_uid undefined
lately.
Reported by: Scott Ullrich (sullrich gmail.com), pfsense
Reported by: Mister Olli (mister.olli googlemail.com)
Because our rc scripts also open the /etc/ttyv* nodes, it revokes the
console, preventing startup messages from being displayed.
I really have to think about this. Maybe we should just give the console
its own TTY and let it build on top of other TTYs. I'm still not sure
what to do with input handling there.
Even though I thought I fixed the staircase issue (and I was no longer
able to reproduce it), I got some reports of the issue still being
there. It turns out the staircase effect still occurred when
/dev/console was kept open while killing the getty on the same TTY
(ttyv0).
For some reason I can't figure out how the old TTY code dealt with that,
so I assume the issue has always been there. I only exposed it more by
merging consolectl with ttyv0, which means that the issue was present,
even on systems without a serial console.
I'm now marking the console device as being closed when closing the
regular TTY device node. This means that when the getty shuts down,
init(8) will open /dev/console, which means the termios attributes will
always be reset in this case.
in symtab_get method symtab parameter is made constant as this reflects
actual intention and usage of the method
Reviewed by: imp, current@
Approved by: jhb (mentor)
vnode interlock to protect the knote fields [1]. The locking assumes
that shared vnode lock is held, thus we get exclusive access to knote
either by exclusive vnode lock protection, or by shared vnode lock +
vnode interlock.
Do not use kl_locked() method to assert either lock ownership or the
fact that curthread does not own the lock. For shared locks, ownership
is not recorded, e.g. VOP_ISLOCKED can return LK_SHARED for the shared
lock not owned by curthread, causing false positives in kqueue subsystem
assertions about knlist lock.
Remove kl_locked method from knlist lock vector, and add two separate
assertion methods kl_assert_locked and kl_assert_unlocked, that are
supposed to use proper asserts. Change knlist_init accordingly.
Add convenience function knlist_init_mtx to reduce number of arguments
for typical knlist initialization.
Submitted by: jhb [1]
Noted by: jhb [2]
Reviewed by: jhb
Tested by: rnoland
So properly hide the already #ifdef SCTP code with
#if defined(INET) || defined(INET6) as well to get us
closer to a non-INET/INET6 kernel.
Discussed with: tuexen [1]
probe. The current device order is unchanged. This commit just adds the
infrastructure and ABI changes so that it is easier to merge later changes
into 8.x.
- Driver attachments now have an associated pass level. Attachments are
not allowed to probe or attach to drivers until the system-wide pass level
is >= the attachment's pass level. By default driver attachments use the
"last" pass level (BUS_PASS_DEFAULT). Driver's that wish to probe during
an earlier pass use EARLY_DRIVER_MODULE() instead of DRIVER_MODULE() which
accepts the pass level as an additional parameter.
- A new method BUS_NEW_PASS has been added to the bus interface. This
method is invoked when the system-wide pass level is changed to kick off
a rescan of the device tree so that drivers that have just been made
"eligible" can probe and attach.
- The bus_generic_new_pass() function provides a default implementation of
BUS_NEW_PASS(). It first allows drivers that were just made eligible for
this pass to identify new child devices. Then it propogates the rescan to
child devices that already have an attached driver by invoking their
BUS_NEW_PASS() method. It also reprobes devices without a driver.
- BUS_PROBE_NOMATCH() is only invoked for devices that do not have
an attached driver after being scanned during the final pass.
- The bus_set_pass() function is used during boot to raise the pass level.
Currently it is only called once during root_bus_configure() to raise
the pass level to BUS_PASS_DEFAULT. This has the effect of probing all
devices in a single pass identical to previous behavior.
Reviewed by: imp
Approved by: re (kib)
the ROUTETABLES kernel option thus there is no need to include opt_route.h
anymore in all consumers of vnet.h and no longer depend on it for module
builds.
Remove the hidden include in flowtable.h as well and leave the two
explicit #includes in ip_input.c and ip_output.c.
Vnet modules and protocol domains may now register destructor
functions to clean up and release per-module state. The destructor
mechanisms can be triggered by invoking "vimage -d", or a future
equivalent command which will be provided via the new jail framework.
While this patch introduces numerous placeholder destructor functions,
many of those are currently incomplete, thus leaking memory or (even
worse) failing to stop all running timers. Many of such issues are
already known and will be incrementaly fixed over the next weeks in
smaller incremental commits.
Apart from introducing new fields in structs ifnet, domain, protosw
and vnet_net, which requires the kernel and modules to be rebuilt, this
change should have no impact on nooptions VIMAGE builds, since vnet
destructors can only be called in VIMAGE kernels. Moreover,
destructor functions should be in general compiled in only in
options VIMAGE builds, except for kernel modules which can be safely
kldunloaded at run time.
Bump __FreeBSD_version to 800097.
Reviewed by: bz, julian
Approved by: rwatson, kib (re), julian (mentor)
Clists were originally used by the TTY layer as a text buffer interface.
The advantage of clists were that it would allocate a small set of
additional buffers that could be shared between TTYs when needed. In
the modern days we can just allocate some more KBs of memory to keep the
TTYs satisfied. The global cfreelist also requires synchronisation,
which may not be useful when trying to improve scalability.
The MPSAFE TTY layer uses its own text buffers (ttyinq and ttyoutq). We
had a small amount of drivers in the tree that still uses clists, like
the old USB stack and some keyboard drivers. With the old USB stack gone
and the keyboard drivers changed to use a circular buffer, we can safely
remove clists from the kernel.
and used in a large number of files, but also because an increasing number
of incorrect uses of MAC calls were sneaking in due to copy-and-paste of
MAC-aware code without the associated opt_mac.h include.
Discussed with: pjd
a KASSERT to handle it. People are likely to turn off INVARIANTS RSN
and loading an old module can cause garbage-in here.
I saw the issue with an older nvidia driver (x11/nvidia-driver) loading
into a new kernel - a crash wasn't seen 'till sysctl_kern_malloc_stats().
I was lucky that mtp->ks_shortdesc was NULL and not something horrible.
While I'm here, KASSERT that malloc_uninit() isn't passed something that's
not in kmemstatistics.
MFC after: 3 weeks
count of the number of registered policies.
Rather than unconditionally locking sockets before passing them into MAC,
lock them in the MAC entry points only if mac_policy_count is non-zero.
This avoids locking overhead for a number of socket system calls when no
policies are registered, eliminating measurable overhead for the MAC
Framework for the socket subsystem when there are no active policies.
Possibly socket locks should be acquired by policies if they are required
for socket labels, which would further avoid locking overhead when there
are policies but they don't require labeling of sockets, or possibly
don't even implement socket controls.
Obtained from: TrustedBSD Project
shm_dotruncate() and vnode_pager_setsize(). Specifically, if the length of
a shared memory object or a file is truncated such that the length modulo
the page size is between 1 and 511, then all of the page's dirty bits were
cleared. Now, a dirty bit is cleared only if the corresponding block is
truncated in its entirety.
device drivers to use arbitrary VM objects to satisfy individual mmap()
requests.
- A new d_mmap_single(cdev, &foff, objsize, &object, prot) callback is
added to cdevsw. This function is called for each mmap() request.
If it returns ENODEV, then the mmap() request will fall back to using
the device's device pager object and d_mmap(). Otherwise, the method
can return a VM object to satisfy this entire mmap() request via
*object. It can also modify the starting offset into this object via
*foff. This allows device drivers to use the file offset as a cookie
to identify specific VM objects.
- vm_mmap_vnode() has been changed to call vm_mmap_cdev() directly when
mapping V_CHR vnodes. This avoids duplicating all the cdev mmap
handling code and simplifies some of vm_mmap_vnode().
- D_VERSION has been bumped to D_VERSION_02. Older device drivers
using D_VERSION_01 are still supported.
MFC after: 1 month
- Each socket upcall is now invoked with the appropriate socket buffer
locked. It is not permissible to call soisconnected() with this lock
held; however, so socket upcalls now return an integer value. The two
possible values are SU_OK and SU_ISCONNECTED. If an upcall returns
SU_ISCONNECTED, then the soisconnected() will be invoked on the
socket after the socket buffer lock is dropped.
- A new API is provided for setting and clearing socket upcalls. The
API consists of soupcall_set() and soupcall_clear().
- To simplify locking, each socket buffer now has a separate upcall.
- When a socket upcall returns SU_ISCONNECTED, the upcall is cleared from
the receive socket buffer automatically. Note that a SO_SND upcall
should never return SU_ISCONNECTED.
- All this means that accept filters should now return SU_ISCONNECTED
instead of calling soisconnected() directly. They also no longer need
to explicitly clear the upcall on the new socket.
- The HTTP accept filter still uses soupcall_set() to manage its internal
state machine, but other accept filters no longer have any explicit
knowlege of socket upcall internals aside from their return value.
- The various RPC client upcalls currently drop the socket buffer lock
while invoking soreceive() as a temporary band-aid. The plan for
the future is to add a new flag to allow soreceive() to be called with
the socket buffer locked.
- The AIO callback for socket I/O is now also invoked with the socket
buffer locked. Previously sowakeup() would drop the socket buffer
lock only to call aio_swake() which immediately re-acquired the socket
buffer lock for the duration of the function call.
Discussed with: rwatson, rmacklem
Each list describes a logical memory object that is backed by one or more
physical address ranges. To minimize locking, the sglist objects
themselves are immutable once they are shared.
These objects may be used in the future to facilitate I/O requests using
physically-addressed buffers. For the immediate future I plan to use them
to implement a new type of VM object and pager.
Reviewed by: jeff, scottl
MFC after: 1 month
consuming one of its spare fields. The cr_flags field is currently
unused, but will be used for features, including capability mode and
pay-as-you-go audit.
Discussed with: jhb, sson
threads:
- Support up to one netisr thread per CPU, each processings its own
workstream, or set of per-protocol queues. Threads may be bound
to specific CPUs, or allowed to migrate, based on a global policy.
In the future it would be desirable to support topology-centric
policies, such as "one netisr per package".
- Allow each protocol to advertise an ordering policy, which can
currently be one of:
NETISR_POLICY_SOURCE: packets must maintain ordering with respect to
an implicit or explicit source (such as an interface or socket).
NETISR_POLICY_FLOW: make use of mbuf flow identifiers to place work,
as well as allowing protocols to provide a flow generation function
for mbufs without flow identifers (m2flow). Falls back on
NETISR_POLICY_SOURCE if now flow ID is available.
NETISR_POLICY_CPU: allow protocols to inspect and assign a CPU for
each packet handled by netisr (m2cpuid).
- Provide utility functions for querying the number of workstreams
being used, as well as a mapping function from workstream to CPU ID,
which protocols may use in work placement decisions.
- Add explicit interfaces to get and set per-protocol queue limits, and
get and clear drop counters, which query data or apply changes across
all workstreams.
- Add a more extensible netisr registration interface, in which
protocols declare 'struct netisr_handler' structures for each
registered NETISR_ type. These include name, handler function,
optional mbuf to flow ID function, optional mbuf to CPU ID function,
queue limit, and ordering policy. Padding is present to allow these
to be expanded in the future. If no queue limit is declared, then
a default is used.
- Queue limits are now per-workstream, and raised from the previous
IFQ_MAXLEN default of 50 to 256.
- All protocols are updated to use the new registration interface, and
with the exception of netnatm, default queue limits. Most protocols
register as NETISR_POLICY_SOURCE, except IPv4 and IPv6, which use
NETISR_POLICY_FLOW, and will therefore take advantage of driver-
generated flow IDs if present.
- Formalize a non-packet based interface between interface polling and
the netisr, rather than having polling pretend to be two protocols.
Provide two explicit hooks in the netisr worker for start and end
events for runs: netisr_poll() and netisr_pollmore(), as well as a
function, netisr_sched_poll(), to allow the polling code to schedule
netisr execution. DEVICE_POLLING still embeds single-netisr
assumptions in its implementation, so for now if it is compiled into
the kernel, a single and un-bound netisr thread is enforced
regardless of tunable configuration.
In the default configuration, the new netisr implementation maintains
the same basic assumptions as the previous implementation: a single,
un-bound worker thread processes all deferred work, and direct dispatch
is enabled by default wherever possible.
Performance measurement shows a marginal performance improvement over
the old implementation due to the use of batched dequeue.
An rmlock is used to synchronize use and registration/unregistration
using the framework; currently, synchronized use is disabled
(replicating current netisr policy) due to a measurable 3%-6% hit in
ping-pong micro-benchmarking. It will be enabled once further rmlock
optimization has taken place. However, in practice, netisrs are
rarely registered or unregistered at runtime.
A new man page for netisr will follow, but since one doesn't currently
exist, it hasn't been updated.
This change is not appropriate for MFC, although the polling shutdown
handler should be merged to 7-STABLE.
Bump __FreeBSD_version.
Reviewed by: bz
=================
Extend the loader to parse the root file system mount options in /etc/fstab,
and set a new loader variable vfs.root.mountfrom.options with these options.
The root mount options must be a comma-delimited string, as specified in
/etc/fstab.
Only set the vfs.root.mountfrom.options variable if it has not been
set in the environment.
sys/kern/vfs_mount.c
====================
When mounting the root file system, pass the mount options
specified in vfs.root.mountfrom.options, but filter out "rw" and "noro",
since the initial mount of the root file system must be done as "ro".
While we are here, try to add a few hints to the mountroot prompt
to give users and idea what might of gone wrong during mounting
of the root file system.
Reviewed by: jhb (an earlier patch)
and calls to vn_vptocnp() by moving more of the common code to
vn_vptocnp(). Rename vn_vptocnp() to vn_vptocnp_locked() to signify that
cache is locked around the call.
Do not track buffer position by both the pointer and offset, use only
buflen to record the start of the free space.
Export vn_vptocnp() for external consumers as a wrapper around
vn_vptocnp_locked() that locks the cache and handles hold counts.
Tested by: pho
assigning ifnets from one vnet to another. Deletion of vnets is not
yet supported.
The interface is implemented as an ioctl extension so that no syscalls
had to be introduced. This should be acceptable given that the new
interface will be used for a short / interim period only, until the
new jail management framwork gains the capability of managing vnets.
This method for managing vimages / vnets has been in use for the past
7 years without any observable issues.
The userland tool to be used in conjunction with the interim API can be
found in p4: //depot/projects/vimage-commit2/src/usr.sbin/vimage/... and
will most probably never get commited to svn.
While here, bump copyright notices in kern_vimage.c and vimage.h to
cover work done in year 2009.
Approved by: julian (mentor)
Discussed with: bz, rwatson
CPU, if available. This is meant to solve the issue of cpufreq misreporting
speeds on CPUs that boot in a reduced power mode and have only relative
speed control.
permissions, such as VWRITE_ACL. For a filsystems that don't
implement it, there is a default implementation, which works
as a wrapper around VOP_ACCESS.
Reviewed by: rwatson@
The system hostname is now stored in prison0, and the global variable
"hostname" has been removed, as has the hostname_mtx mutex. Jails may
have their own host information, or they may inherit it from the
parent/system. The proper way to read the hostname is via
getcredhostname(), which will copy either the hostname associated with
the passed cred, or the system hostname if you pass NULL. The system
hostname can still be accessed directly (and without locking) at
prison0.pr_host, but that should be avoided where possible.
The "similar information" referred to is domainname, hostid, and
hostuuid, which have also become prison parameters and had their
associated global variables removed.
Approved by: bz (mentor)
- Add rm_init_flags() and accept extended options only for that variation.
- Add a flags space specifically for rm_init_flags(), rather than borrowing
the lock_init() flag space.
- Define flag RM_RECURSE to use instead of LO_RECURSABLE.
- Define flag RM_NOWITNESS to allow an rmlock to be exempt from WITNESS
checking; this wasn't possible previously as rm_init() always passed
LO_WITNESS when initializing an rmlock's struct lock.
- Add RM_SYSINIT_FLAGS().
- Rename embedded mutex in rmlocks to make it more obvious what it is.
- Update consumers.
- Update man page.
the last component is a symlink to something that isn't a directory.
We introduce a new namei flag, TRAILINGSLASH, which is set by lookup()
if the last component is followed by a slash. The trailing slash is
then stripped, as before. If the final component is a symlink,
lookup() will return to namei(), which will expand the symlink and
call lookup() with the new path. When all symlinks have been
resolved, lookup() checks if the TRAILINGSLASH flag is set, and if it
is, and the vnode it ended up with is not a directory, it returns
ENOTDIR.
PR: kern/21768
Submitted by: Eygene Ryabinkin <rea-fbsd@codelabs.ru>
MFC after: 3 weeks
I don't want people to override the mutex when allocating a TTY. It has
to be there, to keep drivers like syscons happy. So I'm creating a
tty_alloc_mutex() which can be used in those cases. tty_alloc_mutex()
should eventually be removed.
The advantage of this approach, is that we can just remove a function,
without breaking the regular API in the future.
Introduce for this operation the reverse NO_ADAPTIVE_SX option.
The flag SX_ADAPTIVESPIN to be passed to sx_init_flags(9) gets suppressed
and the new flag, offering the reversed logic, SX_NOADAPTIVE is added.
Additively implements adaptive spininning for sx held in shared mode.
The spinning limit can be handled through sysctls in order to be tuned
while the code doesn't reach the release, after which time they should
be dropped probabilly.
This change has made been necessary by recent benchmarks where it does
improve concurrency of workloads in presence of high contention
(ie. ZFS).
KPI breakage is documented by __FreeBSD_version bumping, manpage and
UPDATING updates.
Requested by: jeff, kmacy
Reviewed by: jeff
Tested by: pho
Add support for kernel fault injection using KFAIL_POINT_* macros and
fail_point_* infrastructure. Add example fail point in vfs_bio.c to
simulate VM buf pressure.
Approved by: dfr (mentor)
by creating a child jail, which is visible to that jail and to any
parent jails. Child jails may be restricted more than their parents,
but never less. Jail names reflect this hierarchy, being MIB-style
dot-separated strings.
Every thread now points to a jail, the default being prison0, which
contains information about the physical system. Prison0's root
directory is the same as rootvnode; its hostname is the same as the
global hostname, and its securelevel replaces the global securelevel.
Note that the variable "securelevel" has actually gone away, which
should not cause any problems for code that properly uses
securelevel_gt() and securelevel_ge().
Some jail-related permissions that were kept in global variables and
set via sysctls are now per-jail settings. The sysctls still exist for
backward compatibility, used only by the now-deprecated jail(2) system
call.
Approved by: bz (mentor)
get a quick snapshot of the kernel's symbol table including the symbols
from any loaded modules (the symbols are all merged into one symbol
table). Unlike like other implementations, this ksyms driver maps
memory in the process memory space to store the snapshot at the time
/dev/ksyms is opened. It also checks to see if the process has already
a snapshot open and won't allow it to open /dev/ksyms it again until it
closes first. This prevents kernel and process memory from being
exhausted. Note that /dev/ksyms is used by the lockstat(1) command.
Reviewed by: gallatin kib (freebsd-arch)
Approved by: gnn (mentor)
adds probes for mutexes, reader/writer and shared/exclusive locks to
gather contention statistics and other locking information for
dtrace scripts, the lockstat(1M) command and other potential
consumers.
Reviewed by: attilio jhb jb
Approved by: gnn (mentor)