- Always read the character device pointer while the associated devfs vnode
is locked. Also, use dev_ref() to obtain a new reference on the vnode for
the mountpoint. This reference is released on unmount. This mirrors the
earlier fix to FFS.
Reviewed by: kib
lookups:
- Honor the caller's locking flags in udf_root() and udf_vget().
- Set VV_ROOT for the root vnode in udf_vget() instead of only doing it in
udf_root().
- Honor the requested locking flags during pathname lookups in udf_lookup().
- Release the buffer holding the directory data before looking up the vnode
for a given file to avoid a LOR between the "udf" vnode locks and
"bufwait".
- Use vn_vget_ino() to handle ".." lookups.
- Special case "." lookups instead of calling udf_vget(). We have to do
extra checking for the vnode lock for "." lookups.
both node pointer and name component. This does the right thing for
hardlinks to the same node in the same directory.
Submitted by: Yoshihiro Ota <ota j email ne jp>
PR: kern/131356
MFC after: 2 weeks
sequence of pathname components. We walk the list building a string in
the caller's passed in buffer. Currently this only handles path names
in CS8 (character set 8) as that is what mkisofs generates for UDF images.
MFC after: 1 month
- Add a separate set of vnode operations that inherits from the fifo ops
and use it for fifo nodes.
- Add a VOP_SETATTR() method that allows setting the size (by silently
ignoring the requests) of fifos. This is to allow O_TRUNC opens of
fifo devices (e.g. I/O redirection in shells using ">").
- Add a VOP_PRINT() handler while I'm here.
- Align the fifo output in fifo_print() with other vn_printf() output.
- Remove the leading space from lockmgr_printinfo() so its output lines up
in vn_printf().
- lockmgr_printinfo() now ends with a newline, so remove an extra newline
from vn_printf().
So we are no longer interested in the error returned from
the *fs_doio() functions. With that we can remove the
error variable as its value is unused now.
Submitted by: Christoph Mallon christoph.mallon@gmx.de
After running a `make buildkernel', I noticed most of the Giant locks in
sysctl are only caused by a very small amount of sysctl's:
- sysctl.name2oid. This one is locked by SYSCTL_LOCK, just like
sysctl.oidfmt.
- kern.ident, kern.osrelease, kern.version, etc. These are just constant
strings.
- kern.arandom, used by the stack protector. It is already protected by
arc4_mtx.
I also saw the following sysctl's show up. Not as often as the ones
above, but still quite often:
- security.jail.jailed. Also mark security.jail.list as MPSAFE. They
don't need locking or already use allprison_lock.
- kern.devname, used by devname(3), ttyname(3), etc.
This seems to reduce Giant locking inside sysctl by ~75% in my primitive
test setup.
pathname lookups.
- Remove 'i_offset' and 'i_ino' from the ISO node structure and replace
them with local variables in the lookup routine instead.
- Cache a copy of 'i_diroff' for use during a lookup in a local variable.
- Save a copy of the found directory entry in a malloc'd buffer after a
successfull lookup before getting the vnode. This allows us to release
the buffer holding the directory block before calling vget() which
otherwise resulted in a LOR between "bufwait" and the vnode lock.
- Use an inlined version of vn_vget_ino() to handle races with ..
lookups. I had to inline the code here since cd9660 uses an internal
vget routine to save a disk I/O that would otherwise re-read the
directory block.
- Honor the requested locking flags during lookups to allow for shared
locking.
- Honor the requested locking flags passed to VFS_ROOT() and VFS_VGET()
similar to UFS.
- Don't make every ISO 9660 vnode hold a reference on the vnode of the
underlying device vnode of the mountpoint. The mountpoint already
holds a suitable reference.
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.
without corresponding number of fifo_open(). This causes assertion
failure in fifo_close() due to vp->v_fifoinfo being NULL for kernel
with INVARIANTS, or NULL pointer dereference otherwise. In fact, we may
ignore excess calls to fifo_close() without bad consequences.
Turn KASSERT() into the return, and print warning for now.
Tested by: pho
Reviewed by: rwatson
MFC after: 2 weeks
to be caused by a metadata corruption that occurs quite often after
unplugging a pendrive during write activity.
Reviewed by: scottl
Approved by: rwatson (mentor)
Sponsored by: FreeBSD Foundation
pfs_vncache_free() that removes pvd from the list, while it is not yet
put on the list.
Prevent the invalid removal from the list by clearing pvd_next and
pvd_prev for the newly allocated pvd, and only move pfs_vncache list
head when the pvd was at the head.
Suggested and approved by: des
MFC after: 2 weeks
compare map->timestamp with saved timestamp after map read lock is
reacquired, not with saved timestamp + 1. The only consequence of the +1
was unconditional lookup of the next map entry, though.
Tested by: pho
Approved by: des
MFC after: 2 weeks
may need to lock arbitrary vnodes, causing either lock order reversal or
recursive vnode lock acquisition.
Tested by: pho
Approved by: des
MFC after: 2 weeks
do pfs_vncache_alloc() for the same pfs_node and pid. In this case, we
could end up with two vnodes for the pair. Recheck the cache under the
locked pfs_vncache_mutex after all sleeping operations are done [1].
This case mostly cannot happen now because pseudofs uses exclusive vnode
locking for lookup. But it does drop the vnode lock for dotdot lookups,
and Marcus' pseudofs_vptocnp implementation is vulnerable too.
Do not call free() on the struct pfs_vdata after insmntque() failure,
because vp->v_data points to the structure, and pseudofs_reclaim()
frees it by the call to pfs_vncache_free().
Tested by: pho [1]
Approved by: des
MFC after: 2 weeks
anything other than 0. Make it so. This fixes
"panic: VOP_STRATEGY failed bp=0xc320dd90 vp=0xc3b9f648",
encountered when writing to an orphaned filesystem. Reason
for the panic was the following assert:
KASSERT(i == 0, ("VOP_STRATEGY failed bp=%p vp=%p", bp, bp->b_vp));
at vfs_bio:bufstrategy().
Reviewed by: scottl, phk
Approved by: rwatson (mentor)
Sponsored by: FreeBSD Foundation
message for r185765.
Noted by: rdivacky
Requested by: des
Commit message for r185765 should be:
In procfs map handler, and in linprocfs maps handler, do not call
vn_fullpath() while having vm map locked. This is done in anticipation
of the vop_vptocnp commit, that would make vn_fullpath sometime
acquire vnode lock.
Also, in linprocfs, maps handler already acquires vnode lock.
No objections from: des
MFC after: 2 week
sbuf instead of doing uiomove. This allows for reads from non-zero
offsets to work.
Patch is forward-ported des@' one, and was adopted to current code
by dchagin@ and me.
Reviewed by: des (linprocfs part)
PR: kern/101453
MFC after: 1 week
ask NDINIT to return a locked vnode instead of letting it drop the
lock and return a referenced vnode and then relock the vnode a few
lines down. This matches the behavior of other filesystem mount routines.
vnode in question does not need to be held. All the data structures used
during the name lookup are protected by the global name cache lock.
Instead, the caller merely needs to ensure a reference is held on the
vnode (such as vhold()) to keep it from being freed.
In the case of procfs' <pid>/file entry, grab the process lock while we
gain a new reference (via vhold()) on p_textvp to fully close races with
execve(2).
For the kern.proc.vmmap sysctl handler, use a shared vnode lock around
the call to VOP_GETATTR() rather than an exclusive lock.
MFC after: 1 month
and server. This replaces the RPC implementation of the NFS client and
server with the newer RPC implementation originally developed
(actually ported from the userland sunrpc code) to support the NFS
Lock Manager. I have tested this code extensively and I believe it is
stable and that performance is at least equal to the legacy RPC
implementation.
The NFS code currently contains support for both the new RPC
implementation and the older legacy implementation inherited from the
original NFS codebase. The default is to use the new implementation -
add the NFS_LEGACYRPC option to fall back to the old code. When I
merge this support back to RELENG_7, I will probably change this so
that users have to 'opt in' to get the new code.
To use RPCSEC_GSS on either client or server, you must build a kernel
which includes the KGSSAPI option and the crypto device. On the
userland side, you must build at least a new libc, mountd, mount_nfs
and gssd. You must install new versions of /etc/rc.d/gssd and
/etc/rc.d/nfsd and add 'gssd_enable=YES' to /etc/rc.conf.
As long as gssd is running, you should be able to mount an NFS
filesystem from a server that requires RPCSEC_GSS authentication. The
mount itself can happen without any kerberos credentials but all
access to the filesystem will be denied unless the accessing user has
a valid ticket file in the standard place (/tmp/krb5cc_<uid>). There
is currently no support for situations where the ticket file is in a
different place, such as when the user logged in via SSH and has
delegated credentials from that login. This restriction is also
present in Solaris and Linux. In theory, we could improve this in
future, possibly using Brooks Davis' implementation of variant
symlinks.
Supporting RPCSEC_GSS on a server is nearly as simple. You must create
service creds for the server in the form 'nfs/<fqdn>@<REALM>' and
install them in /etc/krb5.keytab. The standard heimdal utility ktutil
makes this fairly easy. After the service creds have been created, you
can add a '-sec=krb5' option to /etc/exports and restart both mountd
and nfsd.
The only other difference an administrator should notice is that nfsd
doesn't fork to create service threads any more. In normal operation,
there will be two nfsd processes, one in userland waiting for TCP
connections and one in the kernel handling requests. The latter
process will create as many kthreads as required - these should be
visible via 'top -H'. The code has some support for varying the number
of service threads according to load but initially at least, nfsd uses
a fixed number of threads according to the value supplied to its '-n'
option.
Sponsored by: Isilon Systems
MFC after: 1 month
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)
In particular following functions KPI results modified:
- bufobj_invalbuf()
- bufsync()
and BO_SYNC() "virtual method" of the buffer objects set.
Main consumers of bufobj functions are affected by this change too and,
in particular, functions which changed their KPI are:
- vinvalbuf()
- g_vfs_close()
Due to the KPI breakage, __FreeBSD_version will be bumped in a later
commit.
As a side note, please consider just temporary the 'curthread' argument
passing to VOP_SYNC() (in bufsync()) as it will be axed out ASAP
Reviewed by: kib
Tested by: Giovanni Trematerra <giovanni dot trematerra at gmail dot com>
sbuf instead of doing uiomove. This allows for reads from non-zero
offsets to work.
Patch is forward-ported des@' one, and was adopted to current code
by dchagin@ and me.
Reviewed by: des (linprocfs part)
PR: kern/101453
MFC after: 1 week
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
filedescriptor into it. Make sure that td_fpop is NULL when calling
d_mmap from dev_pager_getpages().
Change guards against td_fpop field being non-NULL with private state
for another device, and against sudden clearing the td_fpop. This
could occur when either a driver method calls another driver through
the filedescriptor operation, or a page fault happen while driver is
writing to a memory backed by another driver.
Noted by: rwatson
Tested by: rnoland
MFC after: 3 days
When I changed kern_conf.c three months ago I made device unit numbers
equal to (unneeded) device minor numbers. We used to require
bitshifting, because there were eight bits in the middle that were
reserved for a device major number. Not very long after I turned
dev2unit(), minor(), unit2minor() and minor2unit() into macro's.
The unit2minor() and minor2unit() macro's were no-ops.
We'd better not remove these four macro's from the kernel, because there
is a lot of (external) code that may still depend on them. For now it's
harmless to remove all invocations of unit2minor() and minor2unit().
Reviewed by: kib
and bcmp are not the same thing. 'man bcmp' states that the return is
"non-zero" if the two byte strings are not identical. Where as,
'man memcmp' states that the return is the "difference between the
first two differing bytes (treated as unsigned char values" if the
two byte strings are not identical.
So provide a proper memcmp(9), but it is a C implementation not a tuned
assembly implementation. Therefore bcmp(9) should be preferred over memcmp(9).
In the MPSAFE TTY branch I noticed the vfs timestamps inside devfs were
allocated with 0, where the getattr() routine bumps the timestamps to
boottime if the value is below 3600. The reason why it has been designed
like this, is because timestamps during boot are likely to be invalid.
This means that device nodes that are created on demand (posix_openpt())
have timestamps with a value of boottime, which is not what we want.
Solve this by calling vfs_timestamp() inside devfs_alloc().
Discussed with: kib
initialize the vattr structure in VOP_GETATTR() with VATTR_NULL(),
vattr_null() or by zeroing it. Remove these to allow preinitialization
of fields work in vn_stat(). This is needed to get birthtime initialized
correctly.
Submitted by: Jaakko Heinonen <jh saunalahti fi>
Discussed on: freebsd-fs
MFC after: 1 month
NODEV is more appropriate when va_rdev doesn't have a meaningful value.
Submitted by: Jaakko Heinonen <jh saunalahti fi>
Suggested by: bde
Discussed on: freebsd-fs
MFC after: 1 month
initialize va_vaflags and va_spare because they are not part of the
VOP_GETATTR() API. Also don't initialize birthtime to ctime or zero.
Submitted by: Jaakko Heinonen <jh saunalahti fi>
Reviewed by: bde
Discussed on: freebsd-fs
MFC after: 1 month
replaced by file relative sector numbers as the buffer block number when
zero-padding a file during extension. Revert the change, it causes wrong
blocks filled with zeroes on seeking beyond end of file.
PR: kern/47628
Submitted by: tegge
MFC after: 3 days
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
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
performed. Otherwise if ruleset is used by given mountpoint and is empty
it's freed by devfs_ruleset_reap and pointer becomes bogus.
Submitted by: Mateusz Guzik <mjguzik@gmail.com>
PR: kern/124853
needed to promote cdev to cdev_priv, the si_priv pointer was followed.
Use member2struct() to calculate address of the wrapping cdev_priv.
Rename si_priv to __si_reserved.
Tested by: pho
Reviewed by: ed
MFC after: 2 weeks
Except for the case where we use the cloner library (clone_create() and
friends), there is no reason to enforce a unique device minor number
policy. There are various drivers in the source tree that allocate unr
pools and such to provide minor numbers, without using them themselves.
Because we still need to support unique device minor numbers for the
cloner library, introduce a new flag called D_NEEDMINOR. All cdevsw's
that are used in combination with the cloner library should be marked
with this flag to make the cloning work.
This means drivers can now freely use si_drv0 to store their own flags
and state, making it effectively the same as si_drv1 and si_drv2. We
still keep the minor() and dev2unit() routines around to make drivers
happy.
The NTFS code also used the minor number in its hash table. We should
not do this anymore. If the si_drv0 field would be changed, it would no
longer end up in the same list.
Approved by: philip (mentor)
The while loop that is assumed to initialize the uio_off later, may
be not entered at all, causing uninitialized value to be returned in
uio->uio_offset.
PR: 122925
Submitted by: Jaakko Heinonen <jh saunalahti fi>
MFC after: 1 weeks
the dm_lock is held while the newly allocated vnode is locked. Since no
other threads may try to lock the new vnode yet, the LOR there cannot
result in the deadlock.
Shut down the witness warning to note this fact.
Tested by: pho
Prodded by: attilio
As discussed with Robert Watson and John Baldwin, it would be better if
PTY's are created with proper permissions, turning grantpt() into a
no-op.
Bypassing security frameworks like MAC by passing NOCRED to
VOP_SETATTR() will only make things more complex.
Approved by: philip (mentor)
In the mpsafetty branch, PTY's are allocated through the posix_openpt()
system call. The controller side of a PTY now uses its own file
descriptor type (just like sockets, vnodes, pipes, etc).
To remain compatible with existing FreeBSD and Linux C libraries, we can
still create PTY's by opening /dev/ptmx or /dev/ptyXX. These nodes
implement d_fdopen(). Devfs has been slightly changed here, to allow
finit() to be called from d_fdopen().
The routine grantpt() has also been moved into the kernel. This routine
is a little odd, because it needs to bypass standard UNIX permissions.
It needs to change the owner/group/mode of the slave device node, which
may often not be possible. The old implementation solved this by
spawning a setuid utility.
When VOP_SETATTR() is called with NOCRED, devfs_setattr() dereferences
ap->a_cred, causing a kernel panic. Change the de_{uid,gid,mode} code to
allow changes when a->a_cred is set to NOCRED.
Approved by: philip (mentor)
- Use proper synhronization primitives to protect the internal fdesc node cache
used in fdescfs.
- Properly initialize and uninitalize hash.
- Remove unused functions.
Since fdescfs might recurse on itself, adding proper locking to it needed some
tricky workarounds in some parts to make it work. For instance, a descriptor in
fdescfs could refer to an open descriptor to itself, thus forcing the thread to
recurse on vnode locks. Because of this, other race conditions also had to be
fixed.
Tested by: pho
Reviewed by: kib (mentor)
Approved by: kib (mentor)
sense to loop trying to vget() the vnode again.
PR: 122977
Submitted by: Arthur Hartwig <arthur.hartwig nokia com>
Tested by: pho
Reviewed by: jhb
MFC after: 1 week
The patch does not change the cdevsw KBI. Management of the data is
provided by the functions
int devfs_set_cdevpriv(void *priv, cdevpriv_dtr_t dtr);
int devfs_get_cdevpriv(void **datap);
void devfs_clear_cdevpriv(void);
All of the functions are supposed to be called from the cdevsw method
contexts.
- devfs_set_cdevpriv assigns the priv as private data for the file
descriptor which is used to initiate currently performed driver
operation. dtr is the function that will be called when either the
last refernce to the file goes away, the device is destroyed or
devfs_clear_cdevpriv is called.
- devfs_get_cdevpriv is the obvious accessor.
- devfs_clear_cdevpriv allows to clear the private data for the still
open file.
Implementation keeps the driver-supplied pointers in the struct
cdev_privdata, that is referenced both from the struct file and struct
cdev, and cannot outlive any of the referee.
Man pages will be provided after the KPI stabilizes.
Reviewed by: jhb
Useful suggestions from: jeff, antoine
Debugging help and tested by: pho
MFC after: 1 month
the mentioned PR:
- bounds check time->month as it is used as an array index
- fix usage of time->month as array index (month is 1-12)
- fix calculation based on time->day (day is 1-31)
- fix the speedup code as it doesn't calculate correct timestamps before
the year 2000 and reduce the number of calculation in the year-by-year code
- speedup month calculations by replacing the array content with cumulative
values
- add microseconds calculation
- fix an endian problem
PR: kern/97786
Submitted by: Andriy Gapon <avg@topspin.kiev.ua>
Reviewed by: scottl (earlier version)
Approved by: emax (mentor)
MFC after: 1 week
VSOCK has been added as cache target. Now they process
not only VDIR but also VSOCK.
- fixed panic issue caused by cache incorrect free process
by "umount -f"
Submitted by: Masanori OZAWA <ozawa@ongs.co.jp>
MFC after: 1 week
filesystem-specific vnode data to the struct vnode. Provide the
default implementation for the vop_advlock and vop_advlockasync.
Purge the locks on the vnode reclaim by using the lf_purgelocks().
The default implementation is augmented for the nfs and smbfs.
In the nfs_advlock, push the Giant inside the nfs_dolock.
Before the change, the vop_advlock and vop_advlockasync have taken the
unlocked vnode and dereferenced the fs-private inode data, racing with
with the vnode reclamation due to forced unmount. Now, the vop_getattr
under the shared vnode lock is used to obtain the inode size, and
later, in the lf_advlockasync, after locking the vnode interlock, the
VI_DOOMED flag is checked to prevent an operation on the doomed vnode.
The implementation of the lf_purgelocks() is submitted by dfr.
Reported by: kris
Tested by: kris, pho
Discussed with: jeff, dfr
MFC after: 2 weeks
