when all writers, observed by reader, exited. Use writer generation
counter for fifo, and store the snapshot of the fifo generation in the
f_seqcount field of struct file, that is otherwise unused for fifos.
Set FreeBSD-undocumented POLLINIGNEOF flag only when file f_seqcount is
equal to fifo' fi_wgen, and revert r89376.
Fix POLLINIGNEOF for sockets and pipes, and return POLLHUP for them.
Note that the patch does not fix not returning POLLHUP for fifos.
PR: kern/94772
Submitted by: bde (original version)
Reviewed by: rwatson, jilles
Approved by: re (kensmith)
MFC after: 6 weeks (might be)
around the sequence that drop vnode lock and then busies the mount point.
Not having vlocked node or direct reference to the mp allows for the
forced unmount to proceed, making mp unmounted or reused.
Tested by: pho
Reviewed by: jeff
Approved by: re (kensmith)
MFC after: 2 weeks
Note that this does not actually enable full-range i/o requests for
64 architectures, and is done now to update KBI only.
Tested by: pho
Reviewed by: jhb, bde (as part of the review of the bigger patch)
in_ifaddrhead and INADDR_HASH address lists.
Previously, these lists were used unsynchronized as they were effectively
never changed in steady state, but we've seen increasing reports of
writer-writer races on very busy VPN servers as core count has gone up
(and similar configurations where address lists change frequently and
concurrently).
For the time being, use rwlocks rather than rmlocks in order to take
advantage of their better lock debugging support. As a result, we don't
enable ip_input()'s read-locking of INADDR_HASH until an rmlock conversion
is complete and a performance analysis has been done. This means that one
class of reader-writer races still exists.
MFC after: 6 weeks
Reviewed by: bz
rlimit RLIMIT_SWAP that limits the amount of swap that may be reserved
for the uid.
The accounting information (charge) is associated with either map entry,
or vm object backing the entry, assuming the object is the first one
in the shadow chain and entry does not require COW. Charge is moved
from entry to object on allocation of the object, e.g. during the mmap,
assuming the object is allocated, or on the first page fault on the
entry. It moves back to the entry on forks due to COW setup.
The per-entry granularity of accounting makes the charge process fair
for processes that change uid during lifetime, and decrements charge
for proper uid when region is unmapped.
The interface of vm_pager_allocate(9) is extended by adding struct ucred *,
that is used to charge appropriate uid when allocation if performed by
kernel, e.g. md(4).
Several syscalls, among them is fork(2), may now return ENOMEM when
global or per-uid limits are enforced.
In collaboration with: pho
Reviewed by: alc
Approved by: re (kensmith)
vn_open_cred in default implementation. Valid struct ucred is needed for
audit and MAC, and curthread credentials may be wrong.
This further requires modifying the interface of vn_fullpath(9), but it
is out of scope of this change.
Reviewed by: rwatson
Now that we start to use credentials on character devices more often
(because of MPSAFE TTY), move the prison-checks that are in place in the
TTY code into devfs.
Instead of strictly comparing the prisons, use the more common
prison_check() function to compare credentials. This means that
pseudo-terminals are only visible in devfs by processes within the same
jail and parent jails.
Even though regular users in parent jails can now interact with
pseudo-terminals from child jails, this seems to be the right approach.
These processes are also capable of interacting with the jailed
processes anyway, through signals for example.
Reviewed by: kib, rwatson (older version)
NGROUPS_MAX, eliminate ABI dependencies on them, and raise the to 1024
and 1023 respectively. (Previously they were equal, but under a close
reading of POSIX, NGROUPS_MAX was defined to be too large by 1 since it
is the number of supplemental groups, not total number of groups.)
The bulk of the change consists of converting the struct ucred member
cr_groups from a static array to a pointer. Do the equivalent in
kinfo_proc.
Introduce new interfaces crcopysafe() and crsetgroups() for duplicating
a process credential before modifying it and for setting group lists
respectively. Both interfaces take care for the details of allocating
groups array. crsetgroups() takes care of truncating the group list
to the current maximum (NGROUPS) if necessary. In the future,
crsetgroups() may be responsible for insuring invariants such as sorting
the supplemental groups to allow groupmember() to be implemented as a
binary search.
Because we can not change struct xucred without breaking application
ABIs, we leave it alone and introduce a new XU_NGROUPS value which is
always 16 and is to be used or NGRPS as appropriate for things such as
NFS which need to use no more than 16 groups. When feasible, truncate
the group list rather than generating an error.
Minor changes:
- Reduce the number of hand rolled versions of groupmember().
- Do not assign to both cr_gid and cr_groups[0].
- Modify ipfw to cache ucreds instead of part of their contents since
they are immutable once referenced by more than one entity.
Submitted by: Isilon Systems (initial implementation)
X-MFC after: never
PR: bin/113398 kern/133867
missing it.
Remove the "hidden" kernel only include of vimage.h from ip_var.h added
with the very first Vimage commit r181803 to avoid further kernel poisoning.
subsystem. Add a test for VI_DOOMED just after ncl_upgrade_vnlock() in
ncl_bioread_check_cons(). This is required since it is possible
for the vnode to be vgonel()'d while in ncl_upgrade_vnlock() when
a forced dismount is in progress. Also, move the check for VI_DOOMED
in ncl_vinvalbuf() down to after ncl_upgrade_vnlock() and replace the
out of date comment for it.
Approved by: kib (mentor)
be NULL or derefenced memory may become free at arbitrary moment.
Lock the vnode in cd9660, devfs and pseudofs implementation of VOP_IOCTL
to prevent reclaim; check whether the vnode was already reclaimed after
the lock is granted.
Reported by: georg at dts su
Reviewed by: des (pseudofs)
MFC after: 2 weeks
for FreeBSD-CURRENT, the code that checked for and returned the
error was broken. Change it to check for VI_DOOMED set after
vn_lock() and return an error for that case. I believe this
should only happen for forced dismounts.
Approved by: kib (mentor)
behavior for unicode support in UDF so as not to conflict with the MAC
Framework.
Note that Apple's XNU kernel also uses #ifdef MAC for the MAC Framework.
Suggested by: pjd
MFC after: 3 days
and used in a large number of files, but also because an increasing number
of incorrect uses of MAC calls were sneaking in due to copy-and-paste of
MAC-aware code without the associated opt_mac.h include.
Discussed with: pjd
to be set properly on devfs. Otherwise, it isn't possible to set labels
on /dev nodes.
Reported by: Sergio Rodriguez <sergiorr at yahoo.com>
MFC after: 3 days
v_data is not-null before calling NULLVPTOLOWERVP(), and dropping the
interlock allows for reclaim to clean v_data and free the memory.
While there, remove unneeded semicolons and convert the infinite loops
to panics. I have a will to remove null_checkvp() altogether, or leave
it as a trivial stub, but not now.
Reported and tested by: pho
This should not really matter for correctness, since vp->v_lock is
not locked before the call, and null_lock() holds the interlock,
but makes the control flow for reclaim more clear.
Tested by: pho
does NFSv4 Closes in the experimental client's VOP_INACTIVE().
I also replaced a bunch of ap->a_vp with a local copy of vp,
because I thought that made it more readable.
Approved by: kib (mentor)
permissions, such as VWRITE_ACL. For a filsystems that don't
implement it, there is a default implementation, which works
as a wrapper around VOP_ACCESS.
Reviewed by: rwatson@
The system hostname is now stored in prison0, and the global variable
"hostname" has been removed, as has the hostname_mtx mutex. Jails may
have their own host information, or they may inherit it from the
parent/system. The proper way to read the hostname is via
getcredhostname(), which will copy either the hostname associated with
the passed cred, or the system hostname if you pass NULL. The system
hostname can still be accessed directly (and without locking) at
prison0.pr_host, but that should be avoided where possible.
The "similar information" referred to is domainname, hostid, and
hostuuid, which have also become prison parameters and had their
associated global variables removed.
Approved by: bz (mentor)
do them for NFSv4 and flush writes to the server before doing
the Close(s), as required. Also, use the a_td argument instead of
curthread.
Approved by: kib (mentor)
if a local file system supports NFSv4 ACLs. This allows the
NFSHASNFS4ACL() macro to be correctly implemented. The NFSv4 ACL
support should now work when the server exports a ZFS volume.
Approved by: kib (mentor)
by creating a child jail, which is visible to that jail and to any
parent jails. Child jails may be restricted more than their parents,
but never less. Jail names reflect this hierarchy, being MIB-style
dot-separated strings.
Every thread now points to a jail, the default being prison0, which
contains information about the physical system. Prison0's root
directory is the same as rootvnode; its hostname is the same as the
global hostname, and its securelevel replaces the global securelevel.
Note that the variable "securelevel" has actually gone away, which
should not cause any problems for code that properly uses
securelevel_gt() and securelevel_ge().
Some jail-related permissions that were kept in global variables and
set via sysctls are now per-jail settings. The sysctls still exist for
backward compatibility, used only by the now-deprecated jail(2) system
call.
Approved by: bz (mentor)
current NFSv4 ACLs, as defined in sys/acl.h. It still needs a
way to test a mount point for NFSv4 ACL support before it will
work. Until then, the NFSHASNFS4ACL() macro just always returns 0.
Approved by: kib (mentor)
that the range of versions of NFS handled by the server can
be limited. The nfsd daemon must be restarted after these
sysctl variables are changed, in order for the change to take
effect.
Approved by: kib (mentor)
that it handles the case of a non-exported NFSv4 root correctly.
Also, delete handling for the case where nd_repstat is already
set in nfs_proc(), since that no longer happens.
Approved by: kib (mentor)
ReleaseLockOwner operations analagous to what is already
in place for SetClientID and SetClientIDConfirm. These are
the five NFSv4 operations that do not use file handle(s),
so the checks are done using the NFSv4 root export entries
in /etc/exports.
Approved by: kib (mentor)
to it for the client side reply. Hopefully this fixes the
problem with using the new krpc for arm for the experimental
nfs client.
Approved by: kib (mentor)
where a client is not allowed NFSv4 access correctly. This
restriction is specified in the "V4: ..." line(s) in
/etc/exports.
Approved by: kib (mentor)
case of a kerberized mount without a host based principal
name. This will only work for mounts being done by a user
other than root. Support for a host based principal name
will not work until proposed changes to the rpcsec_gss part
of the krpc are committed. It now builds for "options KGSSAPI".
Approved by: kib (mentor)
the code will build when "options KGSSAPI" is specified
without requiring the proposed changes that add host based
initiator principal support. It will not handle the case where
the client uses a host based initiator principal until those
changes are committed. The code that uses those changes is
#ifdef'd notyet until the krpc rpcsec_changes are committed.
Approved by: kib (mentor)
use the newer nmount() style arguments, as is used by mount_nfs.c.
This prepares the kernel code for the use of a mount_nfs.c with
changes for the experimental client integrated into it.
Approved by: kib (mentor)
writes upon close when a write delegation is held by the client.
This should be safe to do, now that nfsv4 Close operations are
delayed until ncl_inactive() is called for the vnode.
Approved by: kib (mentor)
when it runs out of clientids is reboot. I had replaced cpu_reboot()
with printf(), since cpu_reboot() doesn't exist for sparc64.
This change replaces the printf() with panic(), so the reboot
would occur for this highly unlikely occurrence.
Approved by: kib (mentor)
the NFSv4 Close operations until ncl_inactive(). This is
necessary so that the Open StateIDs are available for doing
I/O on mmap'd files after VOP_CLOSE(). I also changed some
indentation for the nfscl_getclose() function.
Approved by: kib (mentor)
experimental nfsv4 server. It was setting the a_id argument
to a fixed value, but that wasn't sufficient for FreeBSD8.
Instead, set l_pid and l_sysid to 0 plus set the F_REMOTE
flag to indicate that these fields are used to check for
same lock owner. Since, for NFSv4, a lockowner is a ClientID plus
an up to 1024byte name, it can't be put in l_sysid easily.
I also renamed the p variable to td, since it's a thread ptr.
Approved by: kib (mentor)
nfsrv_dolocallocks can be changed via sysctl. I also added some non-empty
descriptor strings and reformatted some overly long lines.
Approved by: kib (mentor)
required two changes: setting the program and version numbers before
connect and fixing the handling of the Null Rpc case in newnfs_request().
Approved by: kib (mentor)
experimental nfs subsystem from sys/fs/nfs/nfs.h and sys/fs/nfs/nfsproto.h
to sys/fs/nfs/nfsport.h and rename nfsstat to ext_nfsstat. This was done
so that src/usr.bin/nfsstat.c could use it alongside the regular nfs
include files and struct nfsstat.
Approved by: kib (mentor)
before the struct file is fully initialized in vn_open(), in particular,
fp->f_vnode is NULL. Other thread calling file operation before f_vnode
is set results in NULL pointer dereference in devvn_refthread().
Initialize f_vnode before calling d_fdopen() cdevsw method, that might
set file ops too.
Reported and tested by: Chris Timmons <cwt networks cwu edu>
(RELENG_7 version)
MFC after: 3 days
major/minor numbers of the devices.
Pretending that the vnodes are character devices prevents file tree
walkers from descending into the directories opened by current process.
Also, not doing stat on the filedescriptors prevents the recursive entry
into the VFS.
Requested by: kientzle
Discussed with: Jilles Tjoelker <jilles stack nl>
representing too large integer, instead of overflowing and possibly
returning a random but valid vnode.
Noted by: Jilles Tjoelker <jilles stack nl>
MFC after: 3 days
the VFS. Now all the VFS_* functions and relating parts don't want the
context as long as it always refers to curthread.
In some points, in particular when dealing with VOPs and functions living
in the same namespace (eg. vflush) which still need to be converted,
pass curthread explicitly in order to retain the old behaviour.
Such loose ends will be fixed ASAP.
While here fix a bug: now, UFS_EXTATTR can be compiled alone without the
UFS_EXTATTR_AUTOSTART option.
VFS KPI is heavilly changed by this commit so thirdy parts modules needs
to be recompiled. Bump __FreeBSD_version in order to signal such
situation.
Credential might need to hang around longer than its parent and be used
outside of mnt_explock scope controlling netcred lifetime. Use separate
reference-counted ucred allocated separately instead.
While there, extend mnt_explock coverage in vfs_stdexpcheck and clean-up
some unused declarations in new NFS code.
Reported by: John Hickey
PR: kern/133439
Reviewed by: dfr, kib
support for NFSv4 as well as NFSv2 and 3.
It lives in 3 subdirs under sys/fs:
nfs - functions that are common to the client and server
nfsclient - a mutation of sys/nfsclient that call generic functions
to do RPCs and handle state. As such, it retains the
buffer cache handling characteristics and vnode semantics that
are found in sys/nfsclient, for the most part.
nfsserver - the server. It includes a DRC designed specifically for
NFSv4, that is used instead of the generic DRC in sys/rpc.
The build glue will be checked in later, so at this point, it
consists of 3 new subdirs that should not affect kernel building.
Approved by: kib (mentor)
the removal of NQNFS, but was left in in case it was required for NFSv4.
Since our new NFSv4 client and server can't use it for their
requirements, GC the old mechanism, as well as other unused lease-
related code and interfaces.
Due to its impact on kernel programming and binary interfaces, this
change should not be MFC'd.
Proposed by: jeff
Reviewed by: jeff
Discussed with: rmacklem, zach loafman @ isilon
filesystem supports additional operations using shared vnode locks.
Currently this is used to enable shared locks for open() and close() of
read-only file descriptors.
- When an ISOPEN namei() request is performed with LOCKSHARED, use a
shared vnode lock for the leaf vnode only if the mount point has the
extended shared flag set.
- Set LOCKSHARED in vn_open_cred() for requests that specify O_RDONLY but
not O_CREAT.
- Use a shared vnode lock around VOP_CLOSE() if the file was opened with
O_RDONLY and the mountpoint has the extended shared flag set.
- Adjust md(4) to upgrade the vnode lock on the vnode it gets back from
vn_open() since it now may only have a shared vnode lock.
- Don't enable shared vnode locks on FIFO vnodes in ZFS and UFS since
FIFO's require exclusive vnode locks for their open() and close()
routines. (My recent MPSAFE patches for UDF and cd9660 already included
this change.)
- Enable extended shared operations on UFS, cd9660, and UDF.
Submitted by: ups
Reviewed by: pjd (ZFS bits)
MFC after: 1 month
implementation instead. The bypass does not assume that returned vnode
is only held.
Reported by: Paul B. Mahol <onemda gmail com>, pluknet <pluknet gmail com>
Reviewed by: jhb
Tested by: pho, pluknet <pluknet gmail com>
poll_no_poll().
Return a poll_no_poll() result from devfs_poll_f() when
filedescriptor does not reference the live cdev, instead of ENXIO.
Noted and tested by: hps
MFC after: 1 week
We fail mapping for any udf_bmap_internal error and there can be
different reasons for it, so no need to (over-)emphasize files with
data in fentry.
Submitted by: bde
Approved by: jhb
Previosly readdir missed some directory entries because there was
no space for them in current uio but directory stream offset
was advanced nevertheless.
jhb has discoved the issue and provided a test-case.
Reviewed by: bde
Approved by: jhb (mentor)
Currently bread()-ing through device vnode with
(1) VMIO enabled,
(2) bo_bsize != DEV_BSIZE
(3) more than 1 block
results in data being incorrectly cached.
So instead a more common approach of using a vnode belonging to fs is now
employed.
Also, prevent attempt to bread more than MAXBSIZE bytes because of
adjustments made to account for offset that doesn't start on block
boundary.
Add expanded comments to explain the calculations.
Also drop unused inline function while here.
PR: kern/120967
PR: kern/129084
Reviewed by: scottl, kib
Approved by: jhb (mentor)
... as opposed to files with data in extents.
Some UDF authoring tools produce this type of file for sufficiently small
data files.
Approved by: jhb (mentor)
Use bit-shift instead of division/multiplication.
Act on error as soon as it is detected.
Report attempt to read data embedded in file entry via regular way.
While there, fix lblktosize macro and make use of it.
No functionality should change as a result.
Approved by: jhb (mentor)
msdosfs_unmount() and ffs_unmount() exit early after getting ENXIO.
However, dounmount() treats ENXIO as a success and proceeds with
unmounting. In effect, the filesystem gets unmounted without closing
GEOM provider etc.
Reviewed by: kib
Approved by: rwatson (mentor)
Tested by: dho
Sponsored by: FreeBSD Foundation
Not enough space in user-land buffer is not an error, userland
will read further until eof is reached. So instead of propagating
-1 to caller we convert it to zero/success.
cd9660 code works exactly the same way.
PR: kern/78987
Reviewed by: jhb (mentor)
Approved by: jhb (mentor)
- 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
state transitioning flags and of msleep(9) callings.
Use, instead, an algorithm very similar to what sx(9) and rwlock(9)
alredy do and direct accesses to the sleepqueue(9) primitive.
In order to avoid writer starvation a mechanism very similar to what
rwlock(9) uses now is implemented, with the correspective per-thread
shared lockmgrs counter.
This patch also adds 2 new functions to lockmgr KPI: lockmgr_rw() and
lockmgr_args_rw(). These two are like the 2 "normal" versions, but they
both accept a rwlock as interlock. In order to realize this, the general
lockmgr manager function "__lockmgr_args()" has been implemented through
the generic lock layer. It supports all the blocking primitives, but
currently only these 2 mappers live.
The patch drops the support for WITNESS atm, but it will be probabilly
added soon. Also, there is a little race in the draining code which is
also present in the current CVS stock implementation: if some sharers,
once they wakeup, are in the runqueue they can contend the lock with
the exclusive drainer. This is hard to be fixed but the now committed
code mitigate this issue a lot better than the (past) CVS version.
In addition assertive KA_HELD and KA_UNHELD have been made mute
assertions because they are dangerous and they will be nomore supported
soon.
In order to avoid namespace pollution, stack.h is splitted into two
parts: one which includes only the "struct stack" definition (_stack.h)
and one defining the KPI. In this way, newly added _lockmgr.h can
just include _stack.h.
Kernel ABI results heavilly changed by this commit (the now committed
version of "struct lock" is a lot smaller than the previous one) and
KPI results broken by lockmgr_rw() / lockmgr_args_rw() introduction,
so manpages and __FreeBSD_version will be updated accordingly.
Tested by: kris, pho, jeff, danger
Reviewed by: jeff
Sponsored by: Google, Summer of Code program 2007
the fdesc_allocvp(). The caller of the fdesc_allocvp() expects that the
returned vnode is not reclaimed. Do lock the vnode exclusive and drop
the lock after.
Reported by: pho
Reviewed by: jeff
user-mode lock manager, build a kernel with the NFSLOCKD option and
add '-k' to 'rpc_lockd_flags' in rc.conf.
Highlights include:
* Thread-safe kernel RPC client - many threads can use the same RPC
client handle safely with replies being de-multiplexed at the socket
upcall (typically driven directly by the NIC interrupt) and handed
off to whichever thread matches the reply. For UDP sockets, many RPC
clients can share the same socket. This allows the use of a single
privileged UDP port number to talk to an arbitrary number of remote
hosts.
* Single-threaded kernel RPC server. Adding support for multi-threaded
server would be relatively straightforward and would follow
approximately the Solaris KPI. A single thread should be sufficient
for the NLM since it should rarely block in normal operation.
* Kernel mode NLM server supporting cancel requests and granted
callbacks. I've tested the NLM server reasonably extensively - it
passes both my own tests and the NFS Connectathon locking tests
running on Solaris, Mac OS X and Ubuntu Linux.
* Userland NLM client supported. While the NLM server doesn't have
support for the local NFS client's locking needs, it does have to
field async replies and granted callbacks from remote NLMs that the
local client has contacted. We relay these replies to the userland
rpc.lockd over a local domain RPC socket.
* Robust deadlock detection for the local lock manager. In particular
it will detect deadlocks caused by a lock request that covers more
than one blocking request. As required by the NLM protocol, all
deadlock detection happens synchronously - a user is guaranteed that
if a lock request isn't rejected immediately, the lock will
eventually be granted. The old system allowed for a 'deferred
deadlock' condition where a blocked lock request could wake up and
find that some other deadlock-causing lock owner had beaten them to
the lock.
* Since both local and remote locks are managed by the same kernel
locking code, local and remote processes can safely use file locks
for mutual exclusion. Local processes have no fairness advantage
compared to remote processes when contending to lock a region that
has just been unlocked - the local lock manager enforces a strict
first-come first-served model for both local and remote lockers.
Sponsored by: Isilon Systems
PR: 95247 107555 115524 116679
MFC after: 2 weeks
BO_LOCK/UNLOCK/MTX when manipulating the bufobj.
- Create a new lock in the bufobj to lock bufobj fields independently.
This leaves the vnode interlock as an 'identity' lock while the bufobj
is an io lock. The bufobj lock is ordered before the vnode interlock
and also before the mnt ilock.
- Exploit this new lock order to simplify softdep_check_suspend().
- A few sync related functions are marked with a new XXX to note that
we may not properly interlock against a non-zero bv_cnt when
attempting to sync all vnodes on a mountlist. I do not believe this
race is important. If I'm wrong this will make these locations easier
to find.
Reviewed by: kib (earlier diff)
Tested by: kris, pho (earlier diff)
obtain the reference. In particular, this fixes the panic reported in
the PR. Remove the comments stating that this needs to be done.
PR: kern/119422
MFC after: 1 week
While the KSE project was quite successful in bringing threading to
FreeBSD, the M:N approach taken by the kse library was never developed
to its full potential. Backwards compatibility will be provided via
libmap.conf for dynamically linked binaries and static binaries will
be broken.
than rely on the lockmgr support [1]:
* bump the waiters only if the interlock is held
* let brelvp() return the waiters count
* rely on brelvp() instead than BUF_LOCKWAITERS() in order to check
for the waiters number
- Remove a namespace pollution introduced recently with lockmgr.h
including lock.h by including lock.h directly in the consumers and
making it mandatory for using lockmgr.
- Modify flags accepted by lockinit():
* introduce LK_NOPROFILE which disables lock profiling for the
specified lockmgr
* introduce LK_QUIET which disables ktr tracing for the specified
lockmgr [2]
* disallow LK_SLEEPFAIL and LK_NOWAIT to be passed there so that it
can only be used on a per-instance basis
- Remove BUF_LOCKWAITERS() and lockwaiters() as they are no longer
used
This patch breaks KPI so __FreBSD_version will be bumped and manpages
updated by further commits. Additively, 'struct buf' changes results in
a disturbed ABI also.
[2] Really, currently there is no ktr tracing in the lockmgr, but it
will be added soon.
[1] Submitted by: kib
Tested by: pho, Andrea Barberio <insomniac at slackware dot it>
always curthread.
As KPI gets broken by this patch, manpages and __FreeBSD_version will be
updated by further commits.
Tested by: Andrea Barberio <insomniac at slackware dot it>
namespace in order to handle lockmgr fields in a controlled way instead
than spreading all around bogus stubs:
- VN_LOCK_AREC() allows lock recursion for a specified vnode
- VN_LOCK_ASHARE() allows lock sharing for a specified vnode
In FFS land:
- BUF_AREC() allows lock recursion for a specified buffer lock
- BUF_NOREC() disallows recursion for a specified buffer lock
Side note: union_subr.c::unionfs_node_update() is the only other function
directly handling lockmgr fields. As this is not simple to fix, it has
been left behind as "sole" exception.
macros. The only semantic change was the need to add a vc_opened field
to struct vcomm since we can no longer use the request queue returning
to an uninitialized state to hold whether or not the device is open.
MFC after: 1 month
fundamentally fairly confused about how signals work and when it is
appropriate for upcalls to be interrupted. In particular, we should
be exempting certain upcalls from interruption, we should not always
eventually time out sleeping on a upcall, and we should not be
interrupting the sleep for certain signals that we currently are
(including SIGINFO). This code needs to be reworked in the style of
NFS interruptible mounts.
MFC after: 1 month
access cache improvements:
- Flush just access control state on CODA_PURGEUSER, not the full
namecache for /coda.
- When replacing a fid on a cnode as a result of, e.g.,
reintegration after offline operation, we no longer need to
purge the namecache entries associated with its vnode.
MFC after: 1 month
modeled on the access cache found in NFS, smbfs, and the Linux coda
module. This is a positive access cache of a single entry per file,
tracking recently granted rights, but unlike NFS and smbfs,
supporting explicit invalidation by the distributed file system.
For each cnode, maintain a C_ACCCACHE flag indicating the validity
of the cache, and a cached uid and mode tracking recently granted
positive access control decisions.
Prefer the cache to venus_access() in VOP_ACCESS() if it is valid,
and when we must fall back to venus_access(), update the cache.
Allow Venus to clear the access cache, either the whole cache on
CODA_FLUSH, or just entries for a specific uid on CODA_PURGEUSER.
Unlike the Coda module on Linux, we don't flush all entries on a
user purge using a generation number, we instead walk present
cnodes and clear only entries for the specific user, meaning it is
somewhat more expensive but won't hit all users.
Since the Coda module is agressive about not keeping around
unopened cnodes, the utility of the cache is somewhat limited for
files, but works will for directories. We should make Coda less
agressive about GCing cnodes in VOP_INACTIVE() in order to improve
the effectiveness of in-kernel caching of attributes and access
rights.
MFC after: 1 month
VFS namecache, as is done by the Coda module on Linux. Unlike the Coda
namecache, the global VFS namecache isn't tagged by credential, so use
ore conservative flushing behavior (for now) when CODA_PURGEUSER is
issued by Venus.
This improves overall integration with the FreeBSD VFS, including
allowing __getcwd() to work better, procfs/procstat monitoring, and so
on. This improves shell behavior in many cases, and improves ".."
handling. It may lead to some slowdown until we've implemented a
specific access cache, which should net improve performance, but in the
mean time, lookup access control now always goes to Venus, whereas
previously it didn't.
MFC after: 1 month
