to accomodate the changes.
Here's a list of things that have changed (I may have left out a few); for a
relatively complete list, see http://people.freebsd.org/~bmilekic/mtx_journal
* Remove old (once useful) mcluster code for MCLBYTES > PAGE_SIZE which
nobody uses anymore. It was great while it lasted, but now we're moving
onto bigger and better things (Approved by: wollman).
* Practically re-wrote the allocation macros in sys/sys/mbuf.h to accomodate
new allocations which grab the necessary lock.
* Make sure that necessary mbstat variables are manipulated with
corresponding atomic() routines.
* Changed the "wait" routines, cleaned it up, made one routine that does
the job.
* Generalized MWAKEUP() macro. Got rid of m_retry and m_retryhdr, as they
are now included in the generalized "wait" routines.
* Sleep routines now use msleep().
* Free lists have locks.
* etc... probably other stuff I'm missing...
Things to look out for and work on later:
* find a better way to (dynamically) adjust EXT_COUNTERS
* move necessity to recurse on a lock from drain routines by providing
lock-free lower-level version of MFREE() (and possibly m_free()?).
* checkout include of mutex.h in sys/sys/mbuf.h - probably violating
general philosophy here.
The code has been reviewed quite a bit, but problems may arise... please,
don't panic! Send me Emails: bmilekic@freebsd.org
Reviewed by: jlemon, cp, alfred, others?
performed twice. Eliminate initialization that is already performed
by _aio_aqueue.
aio_physwakeup: Eliminate redundant synchronization that is already
performed by bufdone.
separately (nfs, cd9660 etc) or keept as a first element of structure
referenced by v_data pointer(ffs). Such organization leads to known problems
with stacked filesystems.
From this point vop_no*lock*() functions maintain only interlock lock.
vop_std*lock*() functions maintain built-in v_lock structure using lockmgr().
vop_sharedlock() is compatible with vop_stdunlock(), but maintains a shared
lock on vnode.
If filesystem wishes to export lockmgr compatible lock, it can put an address
of this lock to v_vnlock field. This indicates that the upper filesystem
can take advantage of it and use single lock structure for entire (or part)
of stack of vnodes. This field shouldn't be examined or modified by VFS code
except for initialization purposes.
Reviewed in general by: mckusick
vn_extattr_get() and vn_extattr_set(). vn_extattr_rm() removes the
specified extended attribute from a vnode, authorizing the change as
the kernel (NULL cred).
Obtained from: TrustedBSD Project
* Add lots of comments
* Convert a couple of assertions to KASSERT()
* Minimal whitespace & misapplied {} fixes
* Convert #if 0 to #if COMPILING_LINT for code we presently do not
support, but want to keep available.
Reviewed by: adrian, markm
must be held when retrieving ACLs from vnodes. This is required for
EA-based UFS ACL implementations.
o Update vacl_get_acl() so that it does appropriate vnode locking.
o Remove static from M_ACL malloc define so that it is accessible for
consumers of ACLs other than in kern_acl.c
Obtained from: TrustedBSD Project
which hides the 'hole' in the minor bits.
Introduce unit2minor() to do the reverse operation.
Fix some some make_dev() calls which didn't use UID_* or GID_* macros.
Kill the v_hashchain alias macro, it hides the real relationship.
Introduce experimental SI_CHEAPCLONE flag set it on cloned bpfs.
the 128-bit sigset_t changes by moving conditionally (rarely) executed
code to the beginning where it is always executed, and since this code
now involves 3 128-bit operations, the pessimization was relatively
large. This change speeds up lmbench's pipe latency benchmark by
3.5%.
Fixed style bugs in CURSIG().
very bloated, first with 128-bit sigset_t's, then with locking in the
SMP case, then with locking in all cases. The space bloat was probably
also time bloat, partly because the fast path through CURSIG() was
pessimized by the sigset_t changes. This change speeds up lmbench's
pipe-based latency benchmark by 4% on a Celeron. <sys/signalvar.h>
had become very polluted to support the bloat.
filesystem lookup() routine if it unlocks parent directory. This flag should
be carefully tracked by filesystems if they want to work properly with nullfs
and other stacked filesystems.
VFS takes advantage of this flag to perform symantically correct usage
of vrele() instead of vput() if parent directory already unlocked.
If filesystem fails to track this flag then previous codepath in VFS left
unchanged.
Convert UFS code to set PDIRUNLOCK flag if necessary. Other filesystmes will
be changed after some period of testing.
Reviewed in general by: mckusick, dillon, adrian
Obtained from: NetBSD
newbus for referencing device interrupt handlers.
- Move the 'struct intrec' type which describes interrupt sources into
sys/interrupt.h instead of making it just be a x86 structure.
- Don't create 'ithd' and 'intrec' typedefs, instead, just use 'struct ithd'
and 'struct intrec'
- Move the code to translate new-bus interrupt flags into an interrupt thread
priority out of the x86 nexus code and into a MI ithread_priority()
function in sys/kern/kern_intr.c.
- Remove now-uneeded x86-specific headers from sys/dev/ata/ata-all.c and
sys/pci/pci_compat.c.
filesystem may hold the lock. Otherwise unavoidable deadlock will occur.
This shouldn't have any side effects as long as we hold vfs lock.
Obtained from: NetBSD
curproc was initialized. curproc == NULL was interpreted as matching
the process holding Giant... Just skip mtx_enter() and mtx_exit() in
trap() if (curproc == NULL && cold) (&& cold for safety).
released before sleeping and re-acquired before msleep
returns. A compatibility cpp macro has been provided for
tsleep to avoid changing all occurences of it in the kernel.
Remove an assertion that the Giant mutex be held before
calling tsleep or asleep.
This is intended to serve the same purpose as condition
variables, but does not preclude their addition in the
future.
Approved by: jasone
Obtained from: BSD/OS
were not present when dev_mkdb(8) was run.
First the dev_mkdb(8) database is searched, this caters for non-DEVFS
cases where people have renamed a device.
If that fails we ask the kernel using sysctl kern.devname if the device
driver has put a name in the dev_t. This covers DEVFS cloned devices.
If that also fails we format a string which isn't entirely useless.
macros that expand to pass filename and line number information. This is
necessary since we're using inline functions instead of macros now.
Add const to the filename pointers passed througout the mtx and witness
code.
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
Update copyrights.
Introduce a new sysctl node:
net.inet.accf
Although acceptfilters need refcounting to be properly (safely) unloaded
as a temporary hack allow them to be unloaded if the sysctl
net.inet.accf.unloadable is set, this is really for developers who want
to work on thier own filters.
A near complete re-write of the accf_http filter:
1) Parse check if the request is HTTP/1.0 or HTTP/1.1 if not dump
to the application.
Because of the performance implications of this there is a sysctl
'net.inet.accf.http.parsehttpversion' that when set to non-zero
parses the HTTP version.
The default is to parse the version.
2) Check if a socket has filled and dump to the listener
3) optimize the way that mbuf boundries are handled using some voodoo
4) even though you'd expect accept filters to only be used on TCP
connections that don't use m_nextpkt I've fixed the accept filter
for socket connections that use this.
This rewrite of accf_http should allow someone to use them and maintain
full HTTP compliance as long as net.inet.accf.http.parsehttpversion is
set.
sanity check, but it is too easy to run into, eg: making an ACL syscall
when no filesystems have the ACL implementation enabled.
The original reason for the panic was that the VOP_ vector had not been
assigned and therefor could not be passed down the stack.. and there
was no point passing it down since nothing implemented it anyway.
vop_defaultop entries could not pass it on because it had a zero (unknown)
vector that was indistinguishable from another unknown VOP vector.
Anyway, we can do something reasonable in this case, we shouldn't need
to panic here as there is a reasonable recovery option (return EOPNOTSUPP
and dont pass it down the stack).
Requested by: rwatson
chgsbsize(), which are called rather frequently and may be called from an
interrupt context in the case of chgsbsize(). Instead, do the hash table
lookup and maintenance when credentials are changed, which is a lot less
frequent. Add pointers to the uidinfo structures to the ucred and pcred
structures for fast access. Pass a pointer to the credential to chgproccnt()
and chgsbsize() instead of passing the uid. Add a reference count to the
uidinfo structure and use it to decide when to free the structure rather
than freeing the structure when the resource consumption drops to zero.
Move the resource tracking code from kern_proc.c to kern_resource.c. Move
some duplicate code sequences in kern_prot.c to separate helper functions.
Change KASSERTs in this code to unconditional tests and calls to panic().
function which may lead to stack lossage and clobbered variables.
This isn't the case here, but there is no way to tell gcc that.
Work around this in a kinda bizzare way, but it shuts gcc up.
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.
kern.ps_showallprocs. Apparently got lost in the merge process from
the capability patches. Now fixed.
Submitted by: jdp
Obtained from: TrustedBSD Project
kernel can instigate an orderly shutdown but still determine the form of
that shutdown. Make it possible eg. to cleanly shutdown and power off the
system under ACPI when the power button is pressed.
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
time being, the ASU accounting flag will no longer be available, but
may be reinstituted in the future once authorization have been redone.
As it is, the kernel went through contortions in access control to
avoid calling suser, which always set the flag. This will also allow
suser to accept const struct *{cred, proc} arguments.
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
the chgsbsize() call to use a "subject" pointer (&sb.sb_hiwat) and
a u_long target to set it to. The whole thing is splnet().
This fixes a problem that jdp has been able to provoke.
defined. This boils down to conditionally compile the
old signal syscalls.
We might want to extend the types in syscalls.master to
make these syscalls conditionally on something more
appropriate than COMPAT_43.
then treat it as such. This isn't perfect, but should do for things
like GENERIC. When in fallback mode, they will be used if there are NO
other hints.
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
that should be better.
The old code counted references to mbuf clusters by using the offset
of the cluster from the start of memory allocated for mbufs and
clusters as an index into an array of chars, which did the reference
counting. If the external storage was not a cluster then reference
counting had to be done by the code using that external storage.
NetBSD's system of linked lists of mbufs was cosidered, but Alfred
felt it would have locking issues when the kernel was made more
SMP friendly.
The system implimented uses a pool of unions to track external
storage. The union contains an int for counting the references and
a pointer for forming a free list. The reference counts are
incremented and decremented atomically and so should be SMP friendly.
This system can track reference counts for any sort of external
storage.
Access to the reference counting stuff is now through macros defined
in mbuf.h, so it should be easier to make changes to the system in
the future.
The possibility of storing the reference count in one of the
referencing mbufs was considered, but was rejected 'cos it would
often leave extra mbufs allocated. Storing the reference count in
the cluster was also considered, but because the external storage
may not be a cluster this isn't an option.
The size of the pool of reference counters is available in the
stats provided by "netstat -m".
PR: 19866
Submitted by: Bosko Milekic <bmilekic@dsuper.net>
Reviewed by: alfred (glanced at by others on -net)
- stop using the evil 'struct trapframe' argument for mi_startup()
(formerly main()). There are much better ways of doing it.
- do not use prepare_usermode() - setregs() in execve() will do it
all for us as long as the p_md.md_regs pointer is set. (which is
now done in machdep.c rather than init_main.c. The Alpha port did it
this way all along and is much cleaner).
- collect all the magic %cr0 etc register settings into one place and
have the AP's call that instead of using magic numbers (!!) that keep
changing over and over again.
- Make it safe to call kthread_create() earlier, including during the
device probe sequence. It doesn't need the callback mechanism that
NetBSD's version uses.
- kthreads created this way are root-less as they exist before the root
filesystem is mounted. init(1) is set up so that it aquires the root
pointers prior to running. If other kthreads want filesystem acccess
we can make this code more generic.
- set all threads start times once we have decided what time it is.
- init uses a trampoline rather than the evil prepare_usermode() hack.
- kern_descrip.c has a couple of tweaks to deal with forking when there
is no rootdir or cwd etc.
- adjust the early SYSINIT() sequence so that a few prereqisites are in
place. eg: make sure the run queue is initialized before doing forks.
With this, the USB code can easily create a kthread to do the device
tree discovery. (I have tested it, it works nicely).
There are still some open issues before this is truely useful.
- tsleep() does not like working before the clock is running. It
sort-of tries to spin wait, but it can do more useful things now.
- stopping a kthread in kld code at unload time is "interesting" but
we have a solution for that.
The Alpha code needs no changes for this. It already uses pretty much the
same strategies, but a little cleaner.
been done.
Don't allow multiple mount operations with MNT_UPDATE at the same
time on the same mount point. When the first mount operation
completed, MNT_UPDATE was cleared in the mount structure, causing
the second to complete as if it was a no-update mount operation
with the following bad side effects:
- mount structure inserted multiple times onto the mountlist
- vp->v_mountedhere incorrectly set, causing next namei
operation walking into the mountpoint to crash with
a locking against myself panic.
Plug a vnode leak in case vinvalbuf fails.
and VOP_SETEXTATTR to simplify calling from in-kernel consumers,
such as capability code. Both accept a vnode (optionally locked,
with ioflg to indicate that), attribute name, and a buffer + buffer
length in UIO_SYSSPACE. Both authorize the call as a kernel request,
with cred set to NULL for the actual VOP_ calls.
Obtained from: TrustedBSD Project
passing a zero-valued timeout, the code would always sleep for one tick.
Change code to avoid calling tsleep if we have no intention of sleeping.
Bring in bugfix from sys_select.c, r1.60 which also applies here.
Modify error handling slightly; passing in an invalid fd will now result
in EBADF returned in the eventlist, while an attempt to change a knote
which does not exist will result in ENOENT being returned. Previously
such attempts would fail silently without notification.
Pointed out by: nicolas.leonard@animaths.com
Rick Reed (rr@yahoo-inc.com)
panicing and return a status so that we can decide whether to drop
into DDB or panic. If the status from isa_nmi is true, panic the
kernel based on machdep.panic_on_nmi, otherwise if DDB is
enabled, drop to DDB based on machdep.ddb_on_nmi.
Reviewed by: peter, phk
Don't allow cpu entries in the MP table to contain APIC IDs out of range.
Don't write outside array boundaries if an IO APIC entry in the MP table
contains an APIC ID out of range.
Assign APIC IDs for all IO APICs according to section 3.6.6 in the
Intel MP spec:
- If the current APIC ID on an IO APIC doesn't conflict with other
IO APICs or CPUs, that APIC ID should be used. The copy of the MP
table must be updated if the corresponding APIC ID in the MP table
is different.
- If the current APIC ID was in conflict with other units, the
corresponding APIC ID specified in the MP table is checked for conflict.
- If a conflict is still found then fall back to using a new unique ID.
The copy of the MP table must be updated.
- IDs out of range is considered to be in conflict.
During these operations, the IO_TO_ID array cannot be used, since any
conflict would have caused information loss. The array is then corrected,
since all APIC ID conflicts should have been resolved.
PR: 20312, 18919
usb, all in usb.ko. uhub depends on usb. The bug was that the preload
processing only adds a module to the list once it's internal dependencies
are resolved... Since it was not "seeing" the internal usb module it
believed that uhub had a missing dependency.
gcc's internal exit() prototypes and the (futile) hackery that we did to
try and avoid warnings. main() was renamed for similar reasons.
Remove an exit related hack from makesyscalls.sh.
!VFS_AIO case. Lots of things have hooks into here (kqueue, exit(),
sockets, etc), I elected to keep the external interfaces the same
rather than spread more #ifdefs around the kernel.
"kern/sys_generic.c:358: warning: cast discards qualifiers from pointer
target type"
The idea for using the uintptr_t intermediate cast for de-constifying
a pointer was hinted at by bde some time ago.
with an error condition such as EINTR, EWOULDBLOCK, and ERESTART,
are reported to the application, not silently conceal. This
behavior was copied from the {read,write}v() syscalls, and is
appropriate there but not here.
o Correct a bug in extattr_delete() wherein the LOCKLEAF flag is
passed to the wrong argument in namei(), resulting in some
unexpected errors during name resolution, and passing in an unlocked
vnode.
Obtained from: TrustedBSD Project
is not desired, then the user can register an EV_SIGNAL filter to
explicitly catch a signal event.
Change requested by: jayanth, ps, peter
"Why is kevent non-restartable after a signal?"
operation or after it. If the ktrace operation was enabled while the
process was blocked doing IO, the race would allow it to pass down
invalid (uninitialized) data and panic later down the call stack.
allow for that.
o Remember to call NDFREE() if exiting as a result of a failed
vn_start_write() when snapshotting.
Reviewed by: mckusick
Obtained from: TrustedBSD Project
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.
a loop down in pmap_init_pt(). A subtraction causes the number of
pages to become negative, that was assigned to an unsigned variable,
and there is a lot of iteration. The bug is due to the ELF image
activator not properly checking for its files being the correct size
as specified by the ELF header.
The solution is to check that the header doesn't ask for part of a
file when that part of the file doesn't exist. Make sure to set
VEXEC at the proper times to make the executables immutable (remove
race conditions). Also, the ELF format specifiies header entries
that allow embedding of other executables (hence how ld-elf.so.1
gets loaded, but not the same as loading shared libraries), so those
executables need to be set VEXEC, too, so they're immutable.
Reviewed by: peter
interfaces. The original resource_find() returned a pointer to an internal
resource table entry. resource_find_hard() dereferences the actual
passed in value (oops!) - effectively trashing random memory due to
the pointer being passed in with a random initial value.
Submitted by: bde
and remove sysctl oids at will during runtime - they don't rely on
linker sets. Also, the node oids can be referenced by more than
one kernel user, which means that it's possible to create partially
overlapping trees.
Add sysctl contexts to help programmers manage multiple dynamic
oids in convenient way.
Please see the manpages for detailed discussion, and example module
for typical use.
This work is based on ideas and code snippets coming from many
people, among them: Arun Sharma, Jonathan Lemon, Doug Rabson,
Brian Feldman, Kelly Yancey, Poul-Henning Kamp and others. I'd like
to specially thank Brian Feldman for detailed review and style
fixes.
PR: kern/16928
Reviewed by: dfr, green, phk
a NMI occured, you could type continue in DDB and the kernel would
not attempt to detect what type of NMI was recieved. Now we check
for the type of NMI first and then go to DDB if it is enabled.
This will solve the problem with having DDB enabled and getting an
NMI due to some possibly bad error and being able to continue the
operation of the kernel when you really want to panic and know
what happened.
Submitted by: jhb
never expire if poll() or select() was called before the system had been
in multiuser for 1 second. This was caused by only checking to see if
tv_sec was zero rather than checking both tv_sec and tv_usec.
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).
SYSCTL_LONG macro to be consistent with other integer sysctl variables
and require an initial value instead of assuming 0. Update several
sysctl variables to use the unsigned types.
PR: 15251
Submitted by: Kelly Yancey <kbyanc@posi.net>
insertion of a CF card, for random values of N > 1. With these fixes,
I've been able to do 100 insert/remove of the cards w/o a crash with
lots of system activity going on that in the past would help trigger
the crash.
The problem:
FreeBSD creates dev_t's on the fly as they are needed and never
destroys them. These dev_t's point to a struct disk that is used for
housekeeping on the disk. When a device goes away, the struct disk
pointer becomes a dangling pointer. Sometimes when the device comes
back, the pointer will point to the new struct disk (in which case the
insertion will work). Other times it won't (especially if any length
of time has passed, since it is dependent on memory returned from
malloc).
The Fix:
There is one of these dev_t's that is always correct. The
device for the WHOLE_DISK_SLICE is always right. It gets set at
create_disk() time. So, the fix is to spend a little CPU time and
lookup the WHOLE_DISK_SLICE dev_t and use the si_disk from that in
preference to the one that's in the device asking to do the I/O. In
addition, we change the test of si_disk == NULL meaning that the dev
needed to inherit properties from the pdev to dev->si_disk !=
pdev->si_disk. This test is a little stronger than the previous test,
but can sometimes be fooled into not inheriting. However, the results
of this fooling are that the old values will be used, which will
generally always be the same as before. si_drv[12] are the only
values that are copied that might pose a problem. They tend to change
as the si_disk field would change, so it is a hole, but it is a small
hole.
One could correctly argue that one should replace much of this code
with something much much better. I would be on the pro side of that
argument.
Reviewed by: phk (who also ported the original patch to current)
Sponsored by: Timing Solutions
after the acquisition of any advisory locks. This fix corrects a case
in which a process tries to open a file with a non-blocking exclusive
lock. Even if it fails to get the lock it would still truncate the
file even though its open failed. With this change, the truncation
is done only after the lock is successfully acquired.
Obtained from: BSD/OS
o Set access mode to -r--r--r-- if SS_CANTRCVMORE is set and the receive
buffer is empty.
o Set access mode to --w--w--w- is SS_CANTSENDMORE is set.
Discussed with: alfred
instead of a struct iovec * array and int len. Get rid of stupidly trying
to allocate all of the memory and copyin()ing the entire iovec[], and
instead just do the proper VOP_WRITE() in ktrwrite() using a copy of
the struct uio that the syscall originally used.
This solves the DoS which could easily be performed; to work around the
DoS, one could also remove "options KTRACE" from the kernel. This is
a very strong MFC candidate for 4.1.
Found by: art@OpenBSD.org
instead of requiring every caller of linker_load_file() to perform the
check itself. This avoids netgraph loading KLD's when securelevel > 0,
not to mention any future code that may call linker_load_file().
Reviewed by: dfr
On unload, remove references from freelist to memory type defined by module.
Print a warning if module defines and allocate its own memory type, but
didn't free it all on unload.
Reviewed by: peter
Use strtoul(), not strtol() in the hints decoder so that
'flags 0xa0ffa0ff' is not truncated to 0x7fffffff.
Use a stack buffer instead of a static 100 byte bss buffer.
Use \0 for the NUL character.
Remove some ``excessive'' parens.
1) while allocating a uidinfo struct malloc is called with M_WAITOK,
it's possible that while asleep another process by the same user
could have woken up earlier and inserted an entry into the uid
hash table. Having redundant entries causes inconsistancies that
we can't handle.
fix: do a non-waiting malloc, and if that fails then do a blocking
malloc, after waking up check that no one else has inserted an entry
for us already.
2) Because many checks for sbsize were done as "test then set" in a non
atomic manner it was possible to exceed the limits put up via races.
fix: instead of querying the count then setting, we just attempt to
set the count and leave it up to the function to return success or
failure.
3) The uidinfo code was inlining and repeating, lookups and insertions
and deletions needed to be in their own functions for clarity.
Reviewed by: green
When re-adding an event, do not reset the event state. If the event was
pending, it will remain pending. This allows the user to change the udata
field after the event was registered, while not losing any events which
have already occurred.
Reported by: jmg
