the target process was being held locked during the uiomove() call. If the
process calling readdir() was the same as the target process (for instance
'ls /proc/curproc/'), and uiomove() caused a page fault, the result would
be a proc lock recursion. I have no idea how long this has been broken -
possibly ever since pfind() was changed to lock the process it returns.
Also replace the one and only call to procfs_findtextvp() with a direct
test of td->td_proc->p_textvp.
YA pseudofs megacommit, part 2:
- Merge the pfs_vnode and pfs_vdata structures, and make the vnode cache
a doubly-linked list. This eliminates the need to walk the list in
pfs_vncache_free().
- Add an exit callout which revokes vnodes associated with the process
that just exited. Since it needs to lock the cache when it does this,
pfs_vncache_mutex needs MTX_RECURSE.
- Add a third callback to the pfs_node structure. This one simply returns
non-zero if the specified requesting process is allowed to access the
specified node for the specified target process. This is used in
addition to the usual permission checks, e.g. when certain files don't
make sense for certain (system) processes.
- Make sure that pfs_lookup() and pfs_readdir() don't yap about files
which aren't pfs_visible(). Also check pfs_visible() before performing
reads and writes, to prevent the kind of races reported in SA-00:77 and
SA-01:55 (fork a child, open /proc/child/ctl, have that child fork a
setuid binary, and assume control of it).
- Add some more trace points.
- Rearrange the flag constants a little to simplify specifying and testing
for readability and writeability.
pseudofs_vnops.c:
- Track the aforementioned change.
- Add checks to pfs_open() to prevent opening read-only files for writing
or vice versa (pfs_{read,write} would block the actual reads and writes,
but it's still a bug to allow the open() to succeed). Also, return
EOPNOTSUPP if the caller attempts to lock the file.
- Add more trace points.
- Remove hardcoded uid, gid, mode from struct pfs_node; make pfs_getattr()
smart enough to get it right most of the time, and allow for callbacks
to handle the remaining cases. Rework the definition macros to match.
- Add lots of (conditional) debugging output.
- Fix a long-standing bug inherited from procfs: don't pretend to be a
read-only file system. Instead, return EOPNOTSUPP for operations we
truly can't support and allow others to fail silently. In particular,
pfs_lookup() now treats CREATE as LOOKUP. This may need more work.
- In pfs_lookup(), if the parent node is process-dependent, check that
the process in question still exists.
- Implement pfs_open() - its only current function is to check that the
process opening the file can see the process it belongs to.
- Finish adding support for writeable nodes.
- Bump module version number.
- Introduce lots of new bugs.
- Use some simple #define's at the top of the files for proc -> thread
changes instead of having lots of needless #ifdef's in the code.
- Don't try to use struct thread in !FreeBSD code.
- Don't use a few struct lwp's in some of the NetBSD code since it isn't
in their HEAD.
The new diff relative to before KSE is now signficantly smaller and easier
to maintain.
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.
Sorry john! (your next MFC will be a doosie!)
Reviewed by: peter@freebsd.org, dillon@freebsd.org
X-MFC after: ha ha ha ha
linux_getdents uses VOP_READDIR( ..., &ncookies, &cookies ) instead of
VOP_READDIR( ..., NULL, NULL ) because it seems to need the offsets for
linux_dirent and sizeof(dirent) != sizeof(linux_dirent)...
PR: 29467
Submitted by: Michael Reifenberger <root@nihil.plaut.de>
Reviewed by: phk
as there are now "unusual" protection properties to Pmem that differ
from the other files. While I'm at it, introduce proc locking for
the other files, which was previously present only in the Pmem case.
Obtained from: TrustedBSD Project
and so special-casing was introduced to provide extra procfs privilege
to the kmem group. With the advent of non-setgid kmem ps, this code
is no longer required, and in fact, can is potentially harmful as it
allocates privilege to a gid that is increasingly less meaningful.
Knowledge of specific gid's in kernel is also generally bad precedent,
as the kernel security policy doesn't distinguish gid's specifically,
only uid 0.
This commit removes reference to kmem in procfs, both in terms of
access control decisions, and the applying of gid kmem to the
/proc/*/mem file, simplifying the associated code considerably.
Processes are still permitted to access the mem file based on
the debugging policy, so ps -e still works fine for normal
processes and use.
Reviewed by: tmm
Obtained from: TrustedBSD Project
The p_can(...) construct was a premature (and, it turns out,
awkward) abstraction. The individual calls to p_canxxx() better
reflect differences between the inter-process authorization checks,
such as differing checks based on the type of signal. This has
a side effect of improving code readability.
o Replace direct credential authorization checks in ktrace() with
invocation of p_candebug(), while maintaining the special case
check of KTR_ROOT. This allows ktrace() to "play more nicely"
with new mandatory access control schemes, as well as making its
authorization checks consistent with other "debugging class"
checks.
o Eliminate "privused" construct for p_can*() calls which allowed the
caller to determine if privilege was required for successful
evaluation of the access control check. This primitive is currently
unused, and as such, serves only to complicate the API.
Approved by: ({procfs,linprocfs} changes) des
Obtained from: TrustedBSD Project
(this commit is just the first stage). Also add various GIANT_ macros to
formalize the removal of Giant, making it easy to test in a more piecemeal
fashion. These macros will allow us to test fine-grained locks to a degree
before removing Giant, and also after, and to remove Giant in a piecemeal
fashion via sysctl's on those subsystems which the authors believe can
operate without Giant.
Replace the a.out emulation of 'struct linker_set' with something
a little more flexible. <sys/linker_set.h> now provides macros for
accessing elements and completely hides the implementation.
The linker_set.h macros have been on the back burner in various
forms since 1998 and has ideas and code from Mike Smith (SET_FOREACH()),
John Polstra (ELF clue) and myself (cleaned up API and the conversion
of the rest of the kernel to use it).
The macros declare a strongly typed set. They return elements with the
type that you declare the set with, rather than a generic void *.
For ELF, we use the magic ld symbols (__start_<setname> and
__stop_<setname>). Thanks to Richard Henderson <rth@redhat.com> for the
trick about how to force ld to provide them for kld's.
For a.out, we use the old linker_set struct.
NOTE: the item lists are no longer null terminated. This is why
the code impact is high in certain areas.
The runtime linker has a new method to find the linker set
boundaries depending on which backend format is in use.
linker sets are still module/kld unfriendly and should never be used
for anything that may be modular one day.
Reviewed by: eivind
not behaving correctly. Fix by attaching to the correct socket.
Also call so{rw}wakeup in addition to the fifo wakeup, so that any
kqfilters attached to the socket buffer get poked.
Only tun0 -> tun32767 may now be opened as struct ifnet's if_unit
is a short.
It's now possible to open /dev/tun and get a handle back for an available
tun device (use devname to find out what you got).
The implementation uses rman by popular demand (and against my judgement)
to track opened devices and uses the new dev_depends() to ensure that
all make_dev()d devices go away before the module is unloaded.
Reviewed by: phk
dev_t. The dev_depends(dev_t, dev_t) function is for tying them
to each other.
When destroy_dev() is called on a dev_t, all dev_t's depending
on it will also be destroyed (depth first order).
Rewrite the make_dev_alias() to use this dependency facility.
kern/subr_disk.c:
Make the disk mini-layer use dependencies to make sure all
relevant dev_t's are removed when the disk disappears.
Make the disk mini-layer precreate some magic sub devices
which the disk/slice/label code expects to be there.
kern/subr_disklabel.c:
Remove some now unneeded variables.
kern/subr_diskmbr.c:
Remove some ancient, commented out code.
kern/subr_diskslice.c:
Minor cleanup. Use name from dev_t instead of dsname()
real uid, saved uid, real gid, and saved gid to ucred, as well as the
pcred->pc_uidinfo, which was associated with the real uid, only rename
it to cr_ruidinfo so as not to conflict with cr_uidinfo, which
corresponds to the effective uid.
o Remove p_cred from struct proc; add p_ucred to struct proc, replacing
original macro that pointed.
p->p_ucred to p->p_cred->pc_ucred.
o Universally update code so that it makes use of ucred instead of pcred,
p->p_ucred instead of p->p_pcred, cr_ruidinfo instead of p_uidinfo,
cr_{r,sv}{u,g}id instead of p_*, etc.
o Remove pcred0 and its initialization from init_main.c; initialize
cr_ruidinfo there.
o Restruction many credential modification chunks to always crdup while
we figure out locking and optimizations; generally speaking, this
means moving to a structure like this:
newcred = crdup(oldcred);
...
p->p_ucred = newcred;
crfree(oldcred);
It's not race-free, but better than nothing. There are also races
in sys_process.c, all inter-process authorization, fork, exec, and
exit.
o Remove sigio->sio_ruid since sigio->sio_ucred now contains the ruid;
remove comments indicating that the old arrangement was a problem.
o Restructure exec1() a little to use newcred/oldcred arrangement, and
use improved uid management primitives.
o Clean up exit1() so as to do less work in credential cleanup due to
pcred removal.
o Clean up fork1() so as to do less work in credential cleanup and
allocation.
o Clean up ktrcanset() to take into account changes, and move to using
suser_xxx() instead of performing a direct uid==0 comparision.
o Improve commenting in various kern_prot.c credential modification
calls to better document current behavior. In a couple of places,
current behavior is a little questionable and we need to check
POSIX.1 to make sure it's "right". More commenting work still
remains to be done.
o Update credential management calls, such as crfree(), to take into
account new ruidinfo reference.
o Modify or add the following uid and gid helper routines:
change_euid()
change_egid()
change_ruid()
change_rgid()
change_svuid()
change_svgid()
In each case, the call now acts on a credential not a process, and as
such no longer requires more complicated process locking/etc. They
now assume the caller will do any necessary allocation of an
exclusive credential reference. Each is commented to document its
reference requirements.
o CANSIGIO() is simplified to require only credentials, not processes
and pcreds.
o Remove lots of (p_pcred==NULL) checks.
o Add an XXX to authorization code in nfs_lock.c, since it's
questionable, and needs to be considered carefully.
o Simplify posix4 authorization code to require only credentials, not
processes and pcreds. Note that this authorization, as well as
CANSIGIO(), needs to be updated to use the p_cansignal() and
p_cansched() centralized authorization routines, as they currently
do not take into account some desirable restrictions that are handled
by the centralized routines, as well as being inconsistent with other
similar authorization instances.
o Update libkvm to take these changes into account.
Obtained from: TrustedBSD Project
Reviewed by: green, bde, jhb, freebsd-arch, freebsd-audit
This fixes a number of warnings relating to removed cloned devices.
It also makes it possible to recreate deleted devices with
mknod(2). The major/minor arguments are ignored.
systems were repo-copied from sys/miscfs to sys/fs.
- Renamed the following file systems and their modules:
fdesc -> fdescfs, portal -> portalfs, union -> unionfs.
- Renamed corresponding kernel options:
FDESC -> FDESCFS, PORTAL -> PORTALFS, UNION -> UNIONFS.
- Install header files for the above file systems.
- Removed bogus -I${.CURDIR}/../../sys CFLAGS from userland
Makefiles.
vm_mtx does not recurse and is required for most low level
vm operations.
faults can not be taken without holding Giant.
Memory subsystems can now call the base page allocators safely.
Almost all atomic ops were removed as they are covered under the
vm mutex.
Alpha and ia64 now need to catch up to i386's trap handlers.
FFS and NFS have been tested, other filesystems will need minor
changes (grabbing the vm lock when twiddling page properties).
Reviewed (partially) by: jake, jhb
vn_start_write() on the given vnode will be successful. VOP_LEASE() may
help to solve this problem, but its return value ignored nearly everywhere.
For now just assume that the missing upper layer on write means insufficient
access rights (which is correct for most cases).
the number of references on the filesystem root vnode to be both
expected and released. Many filesystems hold an extra reference on
the filesystem root vnode, which must be accounted for when
determining if the filesystem is busy and then released if it isn't
busy. The old `skipvp' approach required individual filesystem
xxx_unmount functions to re-implement much of vflush()'s logic to
deal with the root vnode.
All 9 filesystems that hold an extra reference on the root vnode
got the logic wrong in the case of forced unmounts, so `umount -f'
would always fail if there were any extra root vnode references.
Fix this issue centrally in vflush(), now that we can.
This commit also fixes a vnode reference leak in devfs, which could
result in idle devfs filesystems that refuse to unmount.
Reviewed by: phk, bp
If for some reason DEVFS is undesired, the "NODEVFS" option is
needed now.
Pending any significant issues, DEVFS will be made mandatory in
-current on july 1st so that we can start reaping the full
benefits of having it.
other "system" header files.
Also help the deprecation of lockmgr.h by making it a sub-include of
sys/lock.h and removing sys/lockmgr.h form kernel .c files.
Sort sys/*.h includes where possible in affected files.
OK'ed by: bde (with reservations)
not to mention a compile-time warning about the critical function
becoming unused, by replacing spec_bmap() with vop_stdbmap().
ntfs seems to have the same bug.
The factor for converting specfs block numbers to physical block
numbers is 1, but vop_stdbmap() uses the bogus factor
btodb(ap->a_vp->v_mount->mnt_stat.f_iosize), which is 16 for ffs with
the default block size of 8K. This factor is bogus even for vop_stdbmap()
-- the correct factor is related to the filesystem blocksize which is not
necessarily the same to the optimal i/o size. vop_stdbmap() was apparently
cloned from nfs where these sizes happen to be the same.
There may also be a problem with a_vp->v_mount being null. spec_bmap()
still checks for this, but I think the checks in specfs are dead code
which used to support block devices.
Make 7 filesystems which don't really know about VOP_BMAP rely
on the default vector, rather than more or less complete local
vop_nopbmap() implementations.
to struct mount.
This makes the "struct netexport *" paramter to the vfs_export
and vfs_checkexport interface unneeded.
Consequently that all non-stacking filesystems can use
vfs_stdcheckexp().
At the same time, make it a pointer to a struct netexport
in struct mount, so that we can remove the bogus AF_MAX
and #include <net/radix.h> from <sys/mount.h>
VOP_BWRITE() was a hack which made it possible for NFS client
side to use struct buf with non-bio backing.
This patch takes a more general approach and adds a bp->b_op
vector where more methods can be added.
The success of this patch depends on bp->b_op being initialized
all relevant places for some value of "relevant" which is not
easy to determine. For now the buffers have grown a b_magic
element which will make such issues a tiny bit easier to debug.
It's not finished yet (I still have to find a way to implement process-
dependent nodes without consuming too much memory, and the permission
system needs tightening up), but it's becoming hard to work on without
a repo (I've accidentally almost nuked it once already), and it works
(except for the lack of process-dependent nodes, that is).
I was supposed to commit this a week ago, but timed out waiting for jkh
to reply to some questions I had. Pass him a spoonful of bad karma :)
introduce a new argument, "namespace", rather than relying on a first-
character namespace indicator. This is in line with more recent
thinking on EA interfaces on various mailing lists, including the
posix1e, Linux acl-devel, and trustedbsd-discuss forums. Two namespaces
are defined by default, EXTATTR_NAMESPACE_SYSTEM and
EXTATTR_NAMESPACE_USER, where the primary distinction lies in the
access control model: user EAs are accessible based on the normal
MAC and DAC file/directory protections, and system attributes are
limited to kernel-originated or appropriately privileged userland
requests.
o These API changes occur at several levels: the namespace argument is
introduced in the extattr_{get,set}_file() system call interfaces,
at the vnode operation level in the vop_{get,set}extattr() interfaces,
and in the UFS extended attribute implementation. Changes are also
introduced in the VFS extattrctl() interface (system call, VFS,
and UFS implementation), where the arguments are modified to include
a namespace field, as well as modified to advoid direct access to
userspace variables from below the VFS layer (in the style of recent
changes to mount by adrian@FreeBSD.org). This required some cleanup
and bug fixing regarding VFS locks and the VFS interface, as a vnode
pointer may now be optionally submitted to the VFS_EXTATTRCTL()
call. Updated documentation for the VFS interface will be committed
shortly.
o In the near future, the auto-starting feature will be updated to
search two sub-directories to the ".attribute" directory in appropriate
file systems: "user" and "system" to locate attributes intended for
those namespaces, as the single filename is no longer sufficient
to indicate what namespace the attribute is intended for. Until this
is committed, all attributes auto-started by UFS will be placed in
the EXTATTR_NAMESPACE_SYSTEM namespace.
o The default POSIX.1e attribute names for ACLs and Capabilities have
been updated to no longer include the '$' in their filename. As such,
if you're using these features, you'll need to rename the attribute
backing files to the same names without '$' symbols in front.
o Note that these changes will require changes in userland, which will
be committed shortly. These include modifications to the extended
attribute utilities, as well as to libutil for new namespace
string conversion routines. Once the matching userland changes are
committed, a buildworld is recommended to update all the necessary
include files and verify that the kernel and userland environments
are in sync. Note: If you do not use extended attributes (most people
won't), upgrading is not imperative although since the system call
API has changed, the new userland extended attribute code will no longer
compile with old include files.
o Couple of minor cleanups while I'm there: make more code compilation
conditional on FFS_EXTATTR, which should recover a bit of space on
kernels running without EA's, as well as update copyright dates.
Obtained from: TrustedBSD Project
structure rather than assuming that the device vnode would reside
in the FFS filesystem (which is obviously a broken assumption with
the device filesystem).
proctree lock and the process lock are held when updating p_pptr and
p_oppid. When we are just reaading p_pptr we only need the proc lock and
not a proctree lock as well.
user space. It has already been copied in and mp->mnt_stat.f_mntonname has
already been initialised by the caller.
This fixes a panic on the alpha caused by the fact that the variable
'size' wasn't initialised because the call to copyinstr() bailed out with
an EFAULT error.
An initial tidyup of the mount() syscall and VFS mount code.
This code replaces the earlier work done by jlemon in an attempt to
make linux_mount() work.
* the guts of the mount work has been moved into vfs_mount().
* move `type', `path' and `flags' from being userland variables into being
kernel variables in vfs_mount(). `data' remains a pointer into
userspace.
* Attempt to verify the `type' and `path' strings passed to vfs_mount()
aren't too long.
* rework mount() and linux_mount() to take the userland parameters
(besides data, as mentioned) and pass kernel variables to vfs_mount().
(linux_mount() already did this, I've just tidied it up a little more.)
* remove the copyin*() stuff for `path'. `data' still requires copyin*()
since its a pointer into userland.
* set `mount->mnt_statf_mntonname' in vfs_mount() rather than in each
filesystem. This variable is generally initialised with `path', and
each filesystem can override it if they want to.
* NOTE: f_mntonname is intiailised with "/" in the case of a root mount.
credential structure, ucred (cr->cr_prison).
o Allow jail inheritence to be a function of credential inheritence.
o Abstract prison structure reference counting behind pr_hold() and
pr_free(), invoked by the similarly named credential reference
management functions, removing this code from per-ABI fork/exit code.
o Modify various jail() functions to use struct ucred arguments instead
of struct proc arguments.
o Introduce jailed() function to determine if a credential is jailed,
rather than directly checking pointers all over the place.
o Convert PRISON_CHECK() macro to prison_check() function.
o Move jail() function prototypes to jail.h.
o Emulate the P_JAILED flag in fill_kinfo_proc() and no longer set the
flag in the process flags field itself.
o Eliminate that "const" qualifier from suser/p_can/etc to reflect
mutex use.
Notes:
o Some further cleanup of the linux/jail code is still required.
o It's now possible to consider resolving some of the process vs
credential based permission checking confusion in the socket code.
o Mutex protection of struct prison is still not present, and is
required to protect the reference count plus some fields in the
structure.
Reviewed by: freebsd-arch
Obtained from: TrustedBSD Project
run-time. This is temporary solution until proper kernel Unicode interfaces
are in place and as such was purposely designed to be as tiny as possible
(3 lines of the code not counting comments). The port with conversion routines
for the most popular single-byte languages will be added later today
Reviewed by: bp, "Michael C . Wu" <keichii@iteration.net>
Approved by: bp
mtx_enter(lock, type) becomes:
mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks)
mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized)
similarily, for releasing a lock, we now have:
mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN.
We change the caller interface for the two different types of locks
because the semantics are entirely different for each case, and this
makes it explicitly clear and, at the same time, it rids us of the
extra `type' argument.
The enter->lock and exit->unlock change has been made with the idea
that we're "locking data" and not "entering locked code" in mind.
Further, remove all additional "flags" previously passed to the
lock acquire/release routines with the exception of two:
MTX_QUIET and MTX_NOSWITCH
The functionality of these flags is preserved and they can be passed
to the lock/unlock routines by calling the corresponding wrappers:
mtx_{lock, unlock}_flags(lock, flag(s)) and
mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN
locks, respectively.
Re-inline some lock acq/rel code; in the sleep lock case, we only
inline the _obtain_lock()s in order to ensure that the inlined code
fits into a cache line. In the spin lock case, we inline recursion and
actually only perform a function call if we need to spin. This change
has been made with the idea that we generally tend to avoid spin locks
and that also the spin locks that we do have and are heavily used
(i.e. sched_lock) do recurse, and therefore in an effort to reduce
function call overhead for some architectures (such as alpha), we
inline recursion for this case.
Create a new malloc type for the witness code and retire from using
the M_DEV type. The new type is called M_WITNESS and is only declared
if WITNESS is enabled.
Begin cleaning up some machdep/mutex.h code - specifically updated the
"optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN
and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently
need those.
Finally, caught up to the interface changes in all sys code.
Contributors: jake, jhb, jasone (in no particular order)
fsyncs, which typically occur during unmounting, will drain all dirty
buffers even if it takes multiple passes to do so. The guarentee was
mangled by the last patch which solved a problem due to -current disabling
interrupts while holding giant (which caused an infinite spin loop waiting for
I/O to complete). -stable does not have either patch, but has a similar
bug in the original spec_fsync() code which is triggered by a bug in the
softupdates umount code, a fix for which will be committed to -current
as soon as Kirk stamps it. Then both solutions will be MFC'd to -stable.
-stable currently suffers from a combination of the softupdates bug and
a small window of opportunity in the original spec_fsync() code, and -stable
also suffers from the spin-loop bug but since interrupts are enabled the
spin resolves itself in a few milliseconds.
in 4.2-REL which I ripped out in -stable and -current when implementing the
low-memory handling solution. However, maxlaunder turns out to be the saving
grace in certain very heavily loaded systems (e.g. newsreader box). The new
algorithm limits the number of pages laundered in the first pageout daemon
pass. If that is not sufficient then suceessive will be run without any
limit.
Write I/O is now pipelined using two sysctls, vfs.lorunningspace and
vfs.hirunningspace. This prevents excessive buffered writes in the
disk queues which cause long (multi-second) delays for reads. It leads
to more stable (less jerky) and generally faster I/O streaming to disk
by allowing required read ops (e.g. for indirect blocks and such) to occur
without interrupting the write stream, amoung other things.
NOTE: eventually, filesystem write I/O pipelining needs to be done on a
per-device basis. At the moment it is globalized.
of explicit calls to lockmgr. Also provides macros for the flags
pased to specify shared, exclusive or release which map to the
lockmgr flags. This is so that the use of lockmgr can be easily
replaced with optimized reader-writer locks.
- Add some locking that I missed the first time.
Don't check for a null pointer if malloc called with M_WAITOK.
Submitted by: josh@zipperup.org
Submitted by: Robert Drehmel <robd@gmx.net>
Approved by: bp
<sys/proc.h> to <sys/systm.h>.
Correctly document the #includes needed in the manpage.
Add one now needed #include of <sys/systm.h>.
Remove the consequent 48 unused #includes of <sys/proc.h>.
the offending inline function (BUF_KERNPROC) on it being #included
already.
I'm not sure BUF_KERNPROC() is even the right thing to do or in the
right place or implemented the right way (inline vs normal function).
Remove consequently unneeded #includes of <sys/proc.h>
file types to requiring all file types to properly implement fo_stat.
This makes any new file type additions much easier as this code no
longer has to be modified to accomodate it.
o Instead of using curproc in fdesc_allocvp, pass a `struct proc' pointer as
a new fifth parameter.
cheap to setup that it doesn't really matter that we recycle device
vnodes at kleenex speed.
Implement first cut try at killing cloned devices when they are
not needed anymore. For now only the bpf driver is involved in
this experiment. Cloned devices can set the SI_CHEAPCLONE flag
which allows us to destroy_dev() it when the vcount() drops to zero
and the vnode is reclaimed. For now it's a requirement that the
driver doesn't keep persistent state from close to (re)open.
Some whitespace changes.
-- don't depend on garbage in <sys/mount.h>. mbufs aren't actually
used here either. They should have been completely removed from filesystem
interfaces when they were removed from the interfaces to convert between
file handles and vnodes.
Add lockdestroy() and appropriate invocations, which corresponds to
lockinit() and must be called to clean up after a lockmgr lock is no
longer needed.
Replace shared lock on vnode with exclusive one. It shouldn't impact
perfomance as NCP protocol doesn't support outstanding requests.
Do not hold simple lock on vnode for long period of time.
Add functionality to the nwfs_print() routine.
Add correct support for v_object management, so mmap() operation should
work properly.
Add support for extattrctl() routine (submitted by semenu).
At this point nullfs can be considered as functional and much more stable.
In fact, it should behave as a "hard" "symlink" to underlying filesystem.
Reviewed in general by: mckusick, dillon
Parts of logic obtained from: NetBSD
include:
* Mutual exclusion is used instead of spl*(). See mutex(9). (Note: The
alpha port is still in transition and currently uses both.)
* Per-CPU idle processes.
* Interrupts are run in their own separate kernel threads and can be
preempted (i386 only).
Partially contributed by: BSDi (BSD/OS)
Submissions by (at least): cp, dfr, dillon, grog, jake, jhb, sheldonh
to recycle inodes after a destroy_dev() but not until all mounts
have picked up the change.
Add support for an overflow table for DEVFS inodes. The static
table defaults to 1024 inodes, if that fills, an overflow table
of 32k inodes is allocated. Both numbers can be changed at
compile time, the size of the overflow table also with the
sysctl vfs.devfs.noverflow.
Use atomic instructions to barrier between make_dev()/destroy_dev()
and the mounts.
Add lockmgr() locking of directories for operations accessing or
modifying the directory TAILQs.
Various nitpicking here and there.
at this point):
Replace all '#ifdef DEBUG' with '#ifdef NULLFS_DEBUG' and add NULLFSDEBUG
macro.
Protect nullfs hash table with lockmgr.
Use proper order of operations when freeing mnt_data.
Return correct fsid in the null_getattr().
Add null_open() function to catch MNT_NODEV (obtained from NetBSD).
Add null_rename() to catch cross-fs rename operations (submitted by
Ustimenko Semen <semen@iclub.nsu.ru>)
Remove duplicate $FreeBSD$ tags.
cloning infrastructure standard in kern_conf. Modules are now
the same with or without devfs support.
If you need to detect if devfs is present, in modules or elsewhere,
check the integer variable "devfs_present".
This happily removes an ugly hack from kern/vfs_conf.c.
This forces a rename of the eventhandler and the standard clone
helper function.
Include <sys/eventhandler.h> in <sys/conf.h>: it's a helper #include
like <sys/queue.h>
Remove all #includes of opt_devfs.h they no longer matter.
rather than implementing its own {uid,gid,other} checks against vnode
mode. Similar change to linprocfs currently under review.
Obtained from: TrustedBSD Project
int p_can(p1, p2, operation, privused)
which allows specification of subject process, object process,
inter-process operation, and an optional call-by-reference privused
flag, allowing the caller to determine if privilege was required
for the call to succeed. This allows jail, kern.ps_showallprocs and
regular credential-based interaction checks to occur in one block of
code. Possible operations are P_CAN_SEE, P_CAN_SCHED, P_CAN_KILL,
and P_CAN_DEBUG. p_can currently breaks out as a wrapper to a
series of static function checks in kern_prot, which should not
be invoked directly.
o Commented out capabilities entries are included for some checks.
o Update most inter-process authorization to make use of p_can() instead
of manual checks, PRISON_CHECK(), P_TRESPASS(), and
kern.ps_showallprocs.
o Modify suser{,_xxx} to use const arguments, as it no longer modifies
process flags due to the disabling of ASU.
o Modify some checks/errors in procfs so that ENOENT is returned instead
of ESRCH, further improving concealment of processes that should not
be visible to other processes. Also introduce new access checks to
improve hiding of processes for procfs_lookup(), procfs_getattr(),
procfs_readdir(). Correct a bug reported by bp concerning not
handling the CREATE case in procfs_lookup(). Remove volatile flag in
procfs that caused apparently spurious qualifier warnigns (approved by
bde).
o Add comment noting that ktrace() has not been updated, as its access
control checks are different from ptrace(), whereas they should
probably be the same. Further discussion should happen on this topic.
Reviewed by: bde, green, phk, freebsd-security, others
Approved by: bde
Obtained from: TrustedBSD Project
object before falling back on privilege. Make vaccess() accept an
additional optional argument, privused, to determine whether
privilege was required for vaccess() to return 0. Add commented
out capability checks for reference. Rename some variables to make
it more clear which modes/uids/etc are associated with the object,
and which with the access mode.
o Update file system use of vaccess() to pass NULL as the optional
privused argument. Once additional patches are applied, suser()
will no longer set ASU, so privused will permit passing of
privilege information up the stack to the caller.
Reviewed by: bde, green, phk, -security, others
Obtained from: TrustedBSD Project
longs larger than 32 bits or strict alignment requirements.
pm_fatmask had type u_long, but it must have a type that has precisely
32 bits and this type must be no smaller than int, so that ~pmp->pm_fatmask
has no bits above the 31st set. Otherwise, comparisons between (cn
| ~pmp->pm_fatmask) and magic 32-bit "cluster" numbers always fail.
The correct fix is to use the C99 type uint_least32_t and mask with
0xffffffff. The quick fix is to use u_int32_t and assume that ints
have
msdosfs metadata is riddled with unaligned fields, and on alphas,
unaligned_fixup() apparently has problems fixing up the unaligned
accesses caused by this. The quick fix is to not comment out the
NetBSD code that sort of handles this, and define UNALIGNED_ACCESS on
i386's so that the code doesn't change on i386's. The correct fix
would define UNALIGNED_ACCESS in a central machine-dependent header
and maybe add some extra cases to unaligned_fixup(). UNALIGNED_ACCESS
is also tested in isofs.
Submitted by: parts by Mark Abene <phiber@radicalmedia.com>
PR: 19086
Implement subdirs.
Build the full "devicename" for cloning functions.
Fix panic when deleted device goes away.
Collaps devfs_dir and devfs_dirent structures.
Add proper cloning to the /dev/fd* "device-"driver.
Fix a bug in make_dev_alias() handling which made aliases appear
multiple times.
Use devfs_clone to implement getdiskbyname()
Make specfs maintain the stat(2) timestamps per dev_t
Remove old DEVFS support fields from dev_t.
Make uid, gid & mode members of dev_t and set them in make_dev().
Use correct uid, gid & mode in make_dev in disk minilayer.
Add support for registering alias names for a dev_t using the
new function make_dev_alias(). These will show up as symlinks
in DEVFS.
Use makedev() rather than make_dev() for MFSs magic devices to prevent
DEVFS from noticing this abuse.
Add a field for DEVFS inode number in dev_t.
Add new DEVFS in fs/devfs.
Add devfs cloning to:
disk minilayer (ie: ad(4), sd(4), cd(4) etc etc)
md(4), tun(4), bpf(4), fd(4)
If DEVFS add -d flag to /sbin/inits args to make it mount devfs.
Add commented out DEVFS to GENERIC
with the new snapshot code.
Update addaliasu to correctly implement the semantics of the old
checkalias function. When a device vnode first comes into existence,
check to see if an anonymous vnode for the same device was created
at boot time by bdevvp(). If so, adopt the bdevvp vnode rather than
creating a new vnode for the device. This corrects a problem which
caused the kernel to panic when taking a snapshot of the root
filesystem.
Change the calling convention of vn_write_suspend_wait() to be the
same as vn_start_write().
Split out softdep_flushworklist() from softdep_flushfiles() so that
it can be used to clear the work queue when suspending filesystem
operations.
Access to buffers becomes recursive so that snapshots can recursively
traverse their indirect blocks using ffs_copyonwrite() when checking
for the need for copy on write when flushing one of their own indirect
blocks. This eliminates a deadlock between the syncer daemon and a
process taking a snapshot.
Ensure that softdep_process_worklist() can never block because of a
snapshot being taken. This eliminates a problem with buffer starvation.
Cleanup change in ffs_sync() which did not synchronously wait when
MNT_WAIT was specified. The result was an unclean filesystem panic
when doing forcible unmount with heavy filesystem I/O in progress.
Return a zero'ed block when reading a block that was not in use at
the time that a snapshot was taken. Normally, these blocks should
never be read. However, the readahead code will occationally read
them which can cause unexpected behavior.
Clean up the debugging code that ensures that no blocks be written
on a filesystem while it is suspended. Snapshots must explicitly
label the blocks that they are writing during the suspension so that
they do not cause a `write on suspended filesystem' panic.
Reorganize ffs_copyonwrite() to eliminate a deadlock and also to
prevent a race condition that would permit the same block to be
copied twice. This change eliminates an unexpected soft updates
inconsistency in fsck caused by the double allocation.
Use bqrelse rather than brelse for buffers that will be needed
soon again by the snapshot code. This improves snapshot performance.
the gating of system calls that cause modifications to the underlying
filesystem. The gating can be enabled by any filesystem that needs
to consistently suspend operations by adding the vop_stdgetwritemount
to their set of vnops. Once gating is enabled, the function
vfs_write_suspend stops all new write operations to a filesystem,
allows any filesystem modifying system calls already in progress
to complete, then sync's the filesystem to disk and returns. The
function vfs_write_resume allows the suspended write operations to
begin again. Gating is not added by default for all filesystems as
for SMP systems it adds two extra locks to such critical kernel
paths as the write system call. Thus, gating should only be added
as needed.
Details on the use and current status of snapshots in FFS can be
found in /sys/ufs/ffs/README.snapshot so for brevity and timelyness
is not included here. Unless and until you create a snapshot file,
these changes should have no effect on your system (famous last words).
Don't fake any file types, just set vap->va_type to IFTOVT(stb.st_mode).
If something does not report its mode, vap->va_type is set to VNON
accordingly.
using decimal major and minor numbers. "ls -l" reports
disk partitions using decimal major numbers and hex
minor numbers.
make specfs use decimal major numbers and hex minor numbers,
just like "ls -l"
problems when fetch(1) was passed `-o -'. The rationale of this change
is that applications attempting to change underlying vnodes for /dev/fd
nodes are improperly written and the use of this interface should not
ever have been encouraged. Proper alternatives are fchmod, fchown and
others.
PR: 18952
- Remove stale, unused fdescnode->fd_link structure member.
stderr nodes. More specific items of this patch:
o Removed support for symbolic links, and the need for
fdesc_readlink().
o Put all the code from fdesc_attr() into fdesc_getattr() and removed
fdesc_attr(). This also made it easier to properly give all nodes
unique inode numbers.
o The removal of all non-fd nodes allowed the removal of the fdesc_read(),
fdesc_write(), and fdesc_ioctl() nodes, since we no longer have nodes
that get special handling.
o Correct the component name validity-checking in fdesc_lookup(). It
previously detected the end of the string by checking for a terminating
NUL, now it uses cnp->cn_namelen.
o Handle kqueue files as FIFOs. This is probably the closest file type
to represent this type of file there is, and it is unfortunately not
very representative of a kqueue. Creation time is not supported by
kqueue, so ctime, mtime and atime are all set to the current time when
getattr() was called.
o Also set st_[mca]time to the current time since there's no data in
socket structures that can be used to fill this in (FIFOs).
o Simplify fdesc_readdir() since it only has to report the numbered
fd nodes. Add `.' and `..' directory links as well.
o Remove read bits from directories as they tend to confuse programs
like tar(1).
Reviewed by: phk
Discussed with: bde (earlier on, not quite review)
<sys/bio.h>.
<sys/bio.h> is now a prerequisite for <sys/buf.h> but it shall
not be made a nested include according to bdes teachings on the
subject of nested includes.
Diskdrivers and similar stuff below specfs::strategy() should no
longer need to include <sys/buf.> unless they need caching of data.
Still a few bogus uses of struct buf to track down.
Repocopy by: peter
ioccom.h defines only implementation detail, and should therefore
only be included from the #include which defines the ioctl tags,
in other words: never include it from *.c
