Old implemention used Giant to protect the kernel data structures,
but at the same time called malloc(M_WAITOK), that could cause the
calling thread to sleep and lost Giant protection. User-visible
result was the missed wakeup.
New implementation uses one sx lock per futex. The sx protects
the futex structures and allows to sleep while copyin or copyout
are performed.
Unlike linux, we return EINVAL when FUTEX_CMP_REQUEUE operation
is requested and either caller specified futexes are equial or
second futex already exists. This is acceptable since the situation
can only occur from the application error, and glibc falls back to
old FUTEX_WAKE operation when FUTEX_CMP_REQUEUE returns an error.
Approved by: kib (mentor)
MFC after: 1 month
rearrange / replace / adjust several INIT_VNET_* initializer
macros, all of which currently resolve to whitespace.
Reviewed by: bz (an older version of the patch)
Approved by: julian (mentor)
Glibc does not use this operation since 2.3.3 version (Jun 2004),
as it is racy and replaced by FUTEX_CMP_REQUEUE operation.
Glibc versions prior to 2.3.3 fall back to FUTEX_WAKE when
FUTEX_REQUEUE returned EINVAL.
Any application directly using FUTEX_REQUEUE without return
value checking are definitely broken.
Limit quantity of messages per process about unsupported
operation.
Approved by: kib (mentor)
MFC after: 1 month
via the Linux tool.
- Add Linux shim to ipmi(4)
- Create a partitions file to linprocfs to make Linux fdisk see
disks. This file is dynamic so we can see disks come and go.
- Convert msdosfs to vfat in mtab since Linux uses that for
msdosfs.
- In the Linux mount path convert vfat passed in to msdosfs
so Linux mount works on FreeBSD. Note that tasting works
so that if da0 is a msdos file system
/compat/linux/bin/mount /dev/da0 /mnt
works.
- fix a 64it bug for l_off_t.
Grabing sh, mount, fdisk, df from Linux, creating a symlink of mtab to
/compat/linux/etc/mtab and then some careful unpacking of the Linux bmc
update tool and hacking makes it work on newer Dell boxes. Note, probably
if you can't figure out how to do this, then you probably shouldn't be
doing it :-)
ABIs:
- Store the FPU initial control word in the pcb for each thread.
- When first using the FPU, load the initial control word after restoring
the clean state if it is not the standard control word.
- Provide a correct control word for Linux/i386 binaries under
FreeBSD/amd64.
- Adjust the control word returned for fpugetregs()/npxgetregs() when a
thread hasn't used the FPU yet to reflect the real initial control
word for the current ABI.
- The Linux/i386 ABI for FreeBSD/i386 now properly sets the right control
word instead of trashing whatever the current state of the FPU is.
Reviewed by: bde
are used by glibc. This silents the message "2.4+ kernel w/o ELF notes?"
from some programs at start, among them are top and pkill.
Do the assignment of the vector entries in elf_linux_fixup()
as it is done in glibc.
Fix some minor style issues.
Submitted by: Marcin Cieslak <saper at SYSTEM PL>
Approved by: kib (mentor)
MFC after: 1 week
net/route.h.
Remove the hidden include of opt_route.h and net/route.h from net/vnet.h.
We need to make sure that both opt_route.h and net/route.h are included
before net/vnet.h because of the way MRT figures out the number of FIBs
from the kernel option. If we do not, we end up with the default number
of 1 when including net/vnet.h and array sizes are wrong.
This does not change the list of files which depend on opt_route.h
but we can identify them now more easily.
The existing code calls kern_open() to resolve the vnode of a pathname
right after a stat(). This is not correct, because it causes random
character devices to be opened in /dev. This means ls'ing a tape
streamer will cause it to rewind, for example. Changes I have made:
- Add kern_statat_vnhook() to allow binary emulators to `post-process'
struct stat, using the proper vnode.
- Remove unneeded printf's from stat() and statfs().
- Make the Linuxolator use kern_statat_vnhook(), replacing
translate_path_major_minor_at().
- Let translate_fd_major_minor() use vp->v_rdev instead of
vp->v_un.vu_cdev.
Result:
crw-rw-rw- 1 root root 0, 14 Feb 20 13:54 /dev/ptmx
crw--w---- 1 root adm 136, 0 Feb 20 14:03 /dev/pts/0
crw--w---- 1 root adm 136, 1 Feb 20 14:02 /dev/pts/1
crw--w---- 1 ed tty 136, 2 Feb 20 14:03 /dev/pts/2
Before this commit, ptmx also had a major number of 136, because it
silently allocated and deallocated a pseudo-terminal. Device nodes that
cannot be opened now have proper major/minor-numbers.
Reviewed by: kib, netchild, rdivacky (thanks!)
Inside the kernel, the minor() function was responsible for obtaining
the device minor number of a character device. Because we made device
numbers dynamically allocated and independent of the unit number passed
to make_dev() a long time ago, it was actually a misnomer. If you really
want to obtain the device number, you should use dev2udev().
We already converted all the drivers to use dev2unit() to obtain the
device unit number, which is still used by a lot of drivers. I've
noticed not a single driver passes NULL to dev2unit(). Even if they
would, its behaviour would make little sense. This is why I've removed
the NULL check.
Ths commit removes minor(), minor2unit() and unit2minor() from the
kernel. Because there was a naming collision with uminor(), we can
rename umajor() and uminor() back to major() and minor(). This means
that the makedev(3) manual page also applies to kernel space code now.
I suspect umajor() and uminor() isn't used that often in external code,
but to make it easier for other parties to port their code, I've
increased __FreeBSD_version to 800062.
In the existing code we didn't really enforce that callers hold Giant
before calling userland_sysctl(), even though there is no guarantee it
is safe. Fix this by just placing Giant locks around the call to the oid
handler. This also means we only pick up Giant for a very short period
of time. Maybe we should add MPSAFE flags to sysctl or phase it out all
together.
I've also added SYSCTL_LOCK_ASSERT(). We have to make sure sysctl_root()
and name2oid() are called with the sysctl lock held.
Reviewed by: Jille Timmermans <jille quis cx>
directly include only the header files needed. This reduces the
unneeded spamming of various headers into lots of files.
For now, this leaves us with very few modules including vnet.h
and thus needing to depend on opt_route.h.
Reviewed by: brooks, gnn, des, zec, imp
Sponsored by: The FreeBSD Foundation
Change types used in the linux' struct msghdr and struct cmsghdr
definitions to the properly-sized architecture-specific types.
Move ancillary data handler from linux_sendit() to linux_sendmsg().
Submitted by: dchagin
Looking at our source code history, it seems the uname(),
getdomainname() and setdomainname() system calls got deprecated
somewhere after FreeBSD 1.1, but they have never been phased out
properly. Because we don't have a COMPAT_FREEBSD1, just use
COMPAT_FREEBSD4.
Also fix the Linuxolator to build without the setdomainname() routine by
just making it call userland_sysctl on kern.domainname. Also replace the
setdomainname()'s implementation to use this approach, because we're
duplicating code with sysctl_domainname().
I wasn't able to keep these three routines working in our
COMPAT_FREEBSD32, because that would require yet another keyword for
syscalls.master (COMPAT4+NOPROTO). Because this routine is probably
unused already, this won't be a problem in practice. If it turns out to
be a problem, we'll just restore this functionality.
Reviewed by: rdivacky, kib
processes exits at the same time. The linux_emuldata structure is freed
but p->p_emuldata is left as a dangling pointer to the just freed memory.
The check for W_EXIT in the loop scanning the child processes isn't safe
since the state of the child process can change right afterwards. Lock
the process and check the W_EXIT before delivering signal.
Submitted by: tegge
Reviewed by: davidxu
MFC after: 1 week
to add more V* constants, and the variables changed by this patch were often
being assigned to mode_t variables, which is 16 bit.
Approved by: rwatson (mentor)
It is required for async cancellation to work.
Fix PROC_LOCK leak in linux_tgkill when signal delivery attempt is made
to not linux process.
Do not call em_find(p, ...) with p unlocked.
Move common code for linux_tkill() and linux_tgkill() into
linux_do_tkill().
Change linux siginfo_t definition to match actual linux one. Extend
uid fields to 4 bytes from 2. The extension does not change structure
layout and is binary compatible with previous definition, because i386
is little endian, and each uid field has 2 byte padding after it.
Reported by: Nicolas Joly <njoly pasteur fr>
Submitted by: dchangin
MFC after: 1 month
user-mode pointers. Change types used in the structures definitions to
properly-sized architecture-specific types.
Submitted by: dchagin
MFC after: 1 week
syscalls expect the bitmap size in the range from 32 to 128. Old glibc
always assumed size 1024, while newer glibc searches for approriate
size, starting from 1024 and going up.
For now, use FreeBSD size of cpuset_t for bitmap size parameter and
return EINVAL if length of user space bitmap less than our size of
cpuset_t.
Submitted by: dchagin
MFC after: 1 week
[This requires MFC of the actual linux affinity syscalls]
from the vimage project, as per plan established at devsummit 08/08:
http://wiki.freebsd.org/Image/Notes200808DevSummit
Introduce INIT_VNET_*() initializer macros, VNET_FOREACH() iterator
macros, and CURVNET_SET() context setting macros, all currently
resolving to NOPs.
Prepare for virtualization of selected SYSCTL objects by introducing a
family of SYSCTL_V_*() macros, currently resolving to their global
counterparts, i.e. SYSCTL_V_INT() == SYSCTL_INT().
Move selected #defines from sys/sys/vimage.h to newly introduced header
files specific to virtualized subsystems (sys/net/vnet.h,
sys/netinet/vinet.h etc.).
All the changes are verified to have zero functional impact at this
point in time by doing MD5 comparision between pre- and post-change
object files(*).
(*) netipsec/keysock.c did not validate depending on compile time options.
Implemented by: julian, bz, brooks, zec
Reviewed by: julian, bz, brooks, kris, rwatson, ...
Approved by: julian (mentor)
Obtained from: //depot/projects/vimage-commit2/...
X-MFC after: never
Sponsored by: NLnet Foundation, The FreeBSD Foundation
as with getdents64. The last byte is used for storing
the d_type, add this to plain getdents case where it was
missing before. Also change the code to use strlcpy instead
of plain strcpy. This changes fix the getdents crash we
had reports about (hl2 server etc.)
PR: kern/117010
MFC after: 1 week
Submitted by: Dmitry Chagin (dchagin@)
Tested by: MITA Yoshio <mita ee.t.u-tokyo.ac jp>
Approved by: kib (mentor)
The last half year I've been working on a replacement TTY layer for the
FreeBSD kernel. The new TTY layer was designed to improve the following:
- Improved driver model:
The old TTY layer has a driver model that is not abstract enough to
make it friendly to use. A good example is the output path, where the
device drivers directly access the output buffers. This means that an
in-kernel PPP implementation must always convert network buffers into
TTY buffers.
If a PPP implementation would be built on top of the new TTY layer
(still needs a hooks layer, though), it would allow the PPP
implementation to directly hand the data to the TTY driver.
- Improved hotplugging:
With the old TTY layer, it isn't entirely safe to destroy TTY's from
the system. This implementation has a two-step destructing design,
where the driver first abandons the TTY. After all threads have left
the TTY, the TTY layer calls a routine in the driver, which can be
used to free resources (unit numbers, etc).
The pts(4) driver also implements this feature, which means
posix_openpt() will now return PTY's that are created on the fly.
- Improved performance:
One of the major improvements is the per-TTY mutex, which is expected
to improve scalability when compared to the old Giant locking.
Another change is the unbuffered copying to userspace, which is both
used on TTY device nodes and PTY masters.
Upgrading should be quite straightforward. Unlike previous versions,
existing kernel configuration files do not need to be changed, except
when they reference device drivers that are listed in UPDATING.
Obtained from: //depot/projects/mpsafetty/...
Approved by: philip (ex-mentor)
Discussed: on the lists, at BSDCan, at the DevSummit
Sponsored by: Snow B.V., the Netherlands
dcons(4) fixed by: kan
virtualization work done by Marko Zec (zec@).
This is the first in a series of commits over the course
of the next few weeks.
Mark all uses of global variables to be virtualized
with a V_ prefix.
Use macros to map them back to their global names for
now, so this is a NOP change only.
We hope to have caught at least 85-90% of what is needed
so we do not invalidate a lot of outstanding patches again.
Obtained from: //depot/projects/vimage-commit2/...
Reviewed by: brooks, des, ed, mav, julian,
jamie, kris, rwatson, zec, ...
(various people I forgot, different versions)
md5 (with a bit of help)
Sponsored by: NLnet Foundation, The FreeBSD Foundation
X-MFC after: never
V_Commit_Message_Reviewed_By: more people than the patch
We're very lucky, because the flags used by our TIOCPKT implementation
are the same as flags used by Linux. We can safely enable TIOCPKT,
assuming EXTPROC is not used.
TIOCSPTLCK is used by unlockpt(). Because we don't need unlockpt() in
our implementation, make this ioctl a no-op.
Approved by: philip (mentor, implicit), rdivacky
Obtained from: P4 (//depot/projects/mpsafetty/...)
to global hostname and domainname variables. Where necessary, copy
to or from a stack-local buffer before performing copyin() or
copyout(). A few uses, such as in cd9660 and daemon_saver, remain
under-synchronized and will require further updates.
Correct a bug in which a failed copyin() of domainname would leave
domainname potentially corrupted.
MFC after: 3 weeks
In the mpsafetty branch, Linux sshd seems to work properly inside a
jail. Some small modifications had to be made to the Linux compatibility
layer.
The Linux PTY routines always expect the device major number to be 136
or higher. Our code always set the major/minor number pair to 136:0.
This makes routines like ttyname() and ptsname() fail, because we'll end
up having ambiguous device numbers.
The conversion was not performed on all *stat() routines, which meant in
some cases the numbers didn't get transformed. By pushing the conversion
into linux_driver_get_major_minor(), the transformation will take place
on all calls.
Approved by: philip (mentor), rdivacky
what Linux does. This is because robust futexes are mostly
userspace thing which we cannot alter. Two syscalls maintain
pointer to userspace list and when process exits a routine
walks this list waking up processes sleeping on futexes
from that list.
Reviewed by: kib (mentor)
MFC after: 1 month
and linux_openat(). Instead just pass AT_FDCWD into linux_common_open()
for the linux_open() case. This prevents passing -1 as a dirfd to
openat() from succeeding which is wrong.
Suggested by: rwatson, kib
Approved by: kib (mentor)
user-mode lock manager, build a kernel with the NFSLOCKD option and
add '-k' to 'rpc_lockd_flags' in rc.conf.
Highlights include:
* Thread-safe kernel RPC client - many threads can use the same RPC
client handle safely with replies being de-multiplexed at the socket
upcall (typically driven directly by the NIC interrupt) and handed
off to whichever thread matches the reply. For UDP sockets, many RPC
clients can share the same socket. This allows the use of a single
privileged UDP port number to talk to an arbitrary number of remote
hosts.
* Single-threaded kernel RPC server. Adding support for multi-threaded
server would be relatively straightforward and would follow
approximately the Solaris KPI. A single thread should be sufficient
for the NLM since it should rarely block in normal operation.
* Kernel mode NLM server supporting cancel requests and granted
callbacks. I've tested the NLM server reasonably extensively - it
passes both my own tests and the NFS Connectathon locking tests
running on Solaris, Mac OS X and Ubuntu Linux.
* Userland NLM client supported. While the NLM server doesn't have
support for the local NFS client's locking needs, it does have to
field async replies and granted callbacks from remote NLMs that the
local client has contacted. We relay these replies to the userland
rpc.lockd over a local domain RPC socket.
* Robust deadlock detection for the local lock manager. In particular
it will detect deadlocks caused by a lock request that covers more
than one blocking request. As required by the NLM protocol, all
deadlock detection happens synchronously - a user is guaranteed that
if a lock request isn't rejected immediately, the lock will
eventually be granted. The old system allowed for a 'deferred
deadlock' condition where a blocked lock request could wake up and
find that some other deadlock-causing lock owner had beaten them to
the lock.
* Since both local and remote locks are managed by the same kernel
locking code, local and remote processes can safely use file locks
for mutual exclusion. Local processes have no fairness advantage
compared to remote processes when contending to lock a region that
has just been unlocked - the local lock manager enforces a strict
first-come first-served model for both local and remote lockers.
Sponsored by: Isilon Systems
PR: 95247 107555 115524 116679
MFC after: 2 weeks
so the annoying message is not printed.
o Don't warn about FUTEX_FD not being implemented
and return ENOSYS instead of 0 (eg. success).
o Clear FUTEX_PRIVATE_FLAG as we actually implement
only private futexes so there is no reason to
return ENOSYS when app asks for a private futex.
We don't reject shared futexes because they worked
just fine with our implementation so far.
Approved by: kib (mentor)
Tested by: bsam
MFC after: 1 week
