Commit Graph

284 Commits

Author SHA1 Message Date
Konstantin Belousov
a70537835f Provide the mutual exclusion between the nfs export list modifications
and nfs requests processing. Lockmgr lock provides the shared locking for
nfs requests, while exclusive mode is used for modifications. The writer
starvation is handled by lockmgr too.

Reported by:	kris, pho, many
Based on the submission by:	mohan
Tested by:	pho
MFC after:	2 weeks
2008-06-09 10:31:38 +00:00
Wojciech A. Koszek
2e75877f12 Remove checks against DDB, which isn't used in this file.
My intention is to bring no functional change.

Discussion on:	IRC
Reviewed by:	ed, kan, rink,
2008-06-08 20:43:27 +00:00
Craig Rodrigues
a9722ace80 Do not convert the "snapshot" string to the MNT_SNAPSHOT flag here, since
we do it further down in ffs_vfsops.c

MFC after:	1 month
2008-05-23 23:33:07 +00:00
Roman Divacky
d6891277a4 Lock filedesc exclusively when modifying fd_[cr]dir.
This is probably harmless but it's better to lock it
correctly.

Approved by:	kib (mentor)
2008-04-29 21:40:11 +00:00
Poul-Henning Kamp
9b4a8ab7ba Now that all platforms use genclock, shuffle things around slightly
for better structure.

Much of this is related to <sys/clock.h>, which should really have
been called <sys/calendar.h>, but unless and until we need the name,
the repocopy can wait.

In general the kernel does not know about minutes, hours, days,
timezones, daylight savings time, leap-years and such.  All that
is theoretically a matter for userland only.

Parts of kernel code does however care: badly designed filesystems
store timestamps in local time and RTC chips almost universally
track time in a YY-MM-DD HH:MM:SS format, and sometimes in local
timezone instead of UTC.  For this we have <sys/clock.h>

<sys/time.h> on the other hand, deals with time_t, timeval, timespec
and so on.  These know only seconds and fractions thereof.

Move inittodr() and resettodr() prototypes to <sys/time.h>.
Retain the names as it is one of the few surviving PDP/VAX references.

Move startrtclock() to <machine/clock.h> on relevant platforms, it
is a MD call between machdep.c/clock.c.  Remove references to it
elsewhere.

Remove a lot of unnecessary <sys/clock.h> includes.

Move the machdep.disable_rtc_set sysctl to subr_rtc.c where it belongs.
XXX: should be kern.disable_rtc_set really, it's not MD.
2008-04-22 19:38:30 +00:00
Sam Leffler
00c71fb7c3 o add a mountroot event handler that fires when / is mounted; this information
was lost when root started being mounted by init
o remove SI_SUB_MOUNT_ROOT since it's no longer meaningful

MFC after:	2 weeks
2008-04-08 17:53:33 +00:00
Konstantin Belousov
57b4252e45 Add the support for the AT_FDCWD and fd-relative name lookups to the
namei(9).

Based on the submission by rdivacky,
	sponsored by Google Summer of Code 2007
Reviewed by:	rwatson, rdivacky
Tested by:	pho
2008-03-31 12:01:21 +00:00
Konstantin Belousov
1be222e9df Yield the cpu in the kernel while iterating the list of the
vnodes belonging to the mountpoint. Also, yield when in the
softdep_process_worklist() even when we are not going to sleep due to
buffer drain.

It is believed that the ULE fixed the problem [1], but the yielding
seems to be needed at least for the 4BSD case.

Discussed:	on stable@, with bde
Reviewed by:	tegge, jeff [1]
MFC after:	2 weeks
2008-03-23 13:45:24 +00:00
Yaroslav Tykhiy
c6446de05d Undo the damage I did in sys/kern/vfs_mount.c #1.274 and
sbin/mount_nfs/mount_nfs.c #1.76.  Let the dragons sleep.

Requested by:	rodrigc, des
PR:		kern/120319 (welcome the bug back)
2008-02-18 20:58:57 +00:00
Yaroslav Tykhiy
37ed722f78 Add a remark on a questionable property of vfs_mergeopts(). 2008-02-18 10:10:42 +00:00
Yaroslav Tykhiy
38a7fd05f7 In the new order of things dictated by nmount(2), a read-only mount
is to be requested via a "ro" option.  At the same time, MNT_RDONLY
is gradually becoming an indicator of the current state of the FS
instead of a command flag.  Today passing MNT_RDONLY alone to the
kernel's mount machinery will lead to various glitches.  (See the
PRs for examples.)

Therefore mount the root FS with a "ro" option instead of the
MNT_RDONLY flag.  (Note that MNT_RDONLY still is added to the mount
flags internally, by vfs_donmount(), if "ro" was specified.)

To be able to pass "ro" cleanly to kernel_vmount(), teach the latter
function to accept options with NULL values.

Also correct the comment explaining how mount_arg() handles length
of -1.

PR:		bin/106636 kern/120319
Submitted by:	Jaakko Heinonen <see PR kern/120319 for email> (originally)
2008-02-14 17:04:31 +00:00
Attilio Rao
0e9eb108f0 Cleanup lockmgr interface and exported KPI:
- Remove the "thread" argument from the lockmgr() function as it is
  always curthread now
- Axe lockcount() function as it is no longer used
- Axe LOCKMGR_ASSERT() as it is bogus really and no currently used.
  Hopefully this will be soonly replaced by something suitable for it.
- Remove the prototype for dumplockinfo() as the function is no longer
  present

Addictionally:
- Introduce a KASSERT() in lockstatus() in order to let it accept only
  curthread or NULL as they should only be passed
- Do a little bit of style(9) cleanup on lockmgr.h

KPI results heavilly broken by this change, so manpages and
FreeBSD_version will be modified accordingly by further commits.

Tested by: matteo
2008-01-24 12:34:30 +00:00
Attilio Rao
22db15c06f VOP_LOCK1() (and so VOP_LOCK()) and VOP_UNLOCK() are only used in
conjuction with 'thread' argument passing which is always curthread.
Remove the unuseful extra-argument and pass explicitly curthread to lower
layer functions, when necessary.

KPI results broken by this change, which should affect several ports, so
version bumping and manpage update will be further committed.

Tested by: kris, pho, Diego Sardina <siarodx at gmail dot com>
2008-01-13 14:44:15 +00:00
Attilio Rao
cb05b60a89 vn_lock() is currently only used with the 'curthread' passed as argument.
Remove this argument and pass curthread directly to underlying
VOP_LOCK1() VFS method. This modify makes the code cleaner and in
particular remove an annoying dependence helping next lockmgr() cleanup.
KPI results, obviously, changed.

Manpage and FreeBSD_version will be updated through further commits.

As a side note, would be valuable to say that next commits will address
a similar cleanup about VFS methods, in particular vop_lock1 and
vop_unlock.

Tested by:	Diego Sardina <siarodx at gmail dot com>,
		Andrea Di Pasquale <whyx dot it at gmail dot com>
2008-01-10 01:10:58 +00:00
Craig Rodrigues
450ea867c5 In vfs_scanopt(), make sure that the mount option value is not NULL
before calling vsscanf().

PR:		118531
Submitted by:	Jaakko Heinonen <jh saunalahti fi>
MFC after:	3 days
2007-12-31 23:44:53 +00:00
Warner Losh
b27aa20e8d A partial solution to some of the 'pull the umass device with a
mounted FS' problems.  These are more along the lines of 'avoiding an
avoidable panic' than a complete solution to removable devices.  We
now close the barn door after the horse has gotten lose and has been
hit by a truck, as it were.  The barn no longer catches fire in this
case, but the horse is still dead :-).

The vfs_bio.c fix causes us not to put a failed write back into the
dirty pool if the error returned was ENXIO.  In that case, the buffer
is treated like any other clean buffer that's being retured.  ENXIO
means the device isn't there anymore and will never be there again in
the future, so retrying is futile.

The vfs_mount.c fix treats 'ENXIO' as success for unmounting a file
system.  If the device is gone, retrying later won't help and we'll
never be able to unmount the device.

These two are part of a larger patch set submitted by the author.  The
other patches will be forth coming.  I added comments to these two
patches.

Submitted by: Henrik Gulbrandsen
Reviewed by: phk@
PR: usb/46176 (partial)
2007-12-27 16:38:28 +00:00
Craig Rodrigues
62bdb328bb In nmount(), internally convert the mount option: "rdonly" to "ro".
This makes updates mounts such as:
 "mount -u -o rdonly" work more like, "mount -u -o ro".

References to "-o rdonly" were changed to "-o ro" in revision 1.60 of
the mount(8) man page,
but some people still like to use "-o rdonly" since it was documented
in earlier versions of FreeBSD.

Requested by:	rwatson
MFC after:	1 week
2007-12-05 03:26:14 +00:00
Craig Rodrigues
b4b5bf359b In nmount(), if MNT_ROOT is in the mount flags, filter it
out instead of returning an error.
(1)  This makes the behavior consistent with mount(2).
(2)  This makes update mounts on the root file system work properly.
(3)  The explicit checks for MNT_ROOTFS in src/sbin/fsck_ffs/main.c
     and src/usr.sbin/mountd/mountd.c which were put in to
     eliminate errors during update mounts on the root file system
     can be removed.

The only place were MNT_ROOTFS can be validly set
is inside the kernel, i.e. with vfs_mountroot_try().

Reviewed by:	phk
MFC after:	3 days
2007-10-27 15:59:18 +00:00
Robert Watson
30d239bc4c Merge first in a series of TrustedBSD MAC Framework KPI changes
from Mac OS X Leopard--rationalize naming for entry points to
the following general forms:

  mac_<object>_<method/action>
  mac_<object>_check_<method/action>

The previous naming scheme was inconsistent and mostly
reversed from the new scheme.  Also, make object types more
consistent and remove spaces from object types that contain
multiple parts ("posix_sem" -> "posixsem") to make mechanical
parsing easier.  Introduce a new "netinet" object type for
certain IPv4/IPv6-related methods.  Also simplify, slightly,
some entry point names.

All MAC policy modules will need to be recompiled, and modules
not updates as part of this commit will need to be modified to
conform to the new KPI.

Sponsored by:	SPARTA (original patches against Mac OS X)
Obtained from:	TrustedBSD Project, Apple Computer
2007-10-24 19:04:04 +00:00
Konstantin Belousov
245b204491 When restoring the mount after umount failed, the MNTK_UNMOUNT flag
prevents insmntque() from placing reallocated syncer vnode on mount
list, that causes panic in vfs_allocate_syncvnode().

Introduce MNTK_NOINSMNTQ flag, that marks the period when instmntque is
not allowed to success, instead of MNTK_UNMOUNT. The MNTK_NOINSMNTQ is
set and cleared simultaneously with MNTK_UNMOUNT, except on umount error
path, where it is cleaned just before the syncer vnode is going to be
allocated.

Reported by:	Peter Jeremy <peterjeremy optushome com au>
Suggested by:	tegge
Approved by:	re (rwatson)
2007-09-12 16:31:32 +00:00
John Baldwin
1dc5b1cc56 On 6.x this works:
% mount | grep home
/dev/ad4s1e on /home (ufs, local, noatime, soft-updates)
% mount -u -o atime /home
% mount | grep home
/dev/ad4s1e on /home (ufs, local, soft-updates)

Restore this behavior for on 7.x for the following mount options:
noatime, noclusterr, noclusterw, noexec, nosuid, nosymfollow

In addition, on 7.x, the following are equivalent:
mount -u -o atime /home
mount -u -o nonoatime /home

Ideally, when we introduce new mount options, we should avoid
options starting with "no". :)

Requested by:	jhb
Reported by:	Karol Kwiat <karol.kwiat gmail com>, Scott Hetzel <swhetzel gmail com>
Approved by:	re (bmah)
Proxy commit for:	rodrigc
2007-08-15 17:40:09 +00:00
Pawel Jakub Dawidek
68c1a246ae The v_mountedhere field is protected by the vnode lock, not vnode's internal
lock.

Approved by:	re (rwatson)
2007-07-26 16:52:57 +00:00
Craig Rodrigues
d7f81adbd4 Revert previous commits which I committed by mistake.
Approved by:	re (implicit)
Pointy hat to:	me
2007-07-14 21:23:31 +00:00
Craig Rodrigues
d678780e60 The last entry in the ext2_opts array must be NULL,
otherwise the kernel with crash in vfs_filteropt() if an invalid
mount option is passed to ext2fs.

Approved by:	re (kensmith)
2007-07-14 21:18:19 +00:00
Robert Watson
32f9753cfb Eliminate now-unused SUSER_ALLOWJAIL arguments to priv_check_cred(); in
some cases, move to priv_check() if it was an operation on a thread and
no other flags were present.

Eliminate caller-side jail exception checking (also now-unused); jail
privilege exception code now goes solely in kern_jail.c.

We can't yet eliminate suser() due to some cases in the KAME code where
a privilege check is performed and then used in many different deferred
paths.  Do, however, move those prototypes to priv.h.

Reviewed by:	csjp
Obtained from:	TrustedBSD Project
2007-06-12 00:12:01 +00:00
Konstantin Belousov
e5ea32c290 Allow the dounmount() to proceed even for doomed coveredvp.
In dounmount(), before or while vn_lock(coveredvp) is called, coveredvp
vnode may be VI_DOOMED due to one of the following:
- other thread finished unmount and vput()ed it, and vnode was chosen
  for recycling, while vn_lock() slept;
- forced unmount of the coveredvp->v_mount fs.
In the first case, next check for changed v_mountedhere or mnt_gen counter
would be successfull. In the second case, the unmount shall be allowed.

Submitted by:	sobomax
MFC after:	2 weeks
2007-04-26 08:56:56 +00:00
Pawel Jakub Dawidek
7760d8409f Export vfs_mount_alloc() as it is used in ZFS. 2007-04-17 21:14:06 +00:00
Pawel Jakub Dawidek
24b0502ee0 Fix jails and jail-friendly file systems handling:
- We need to allow for PRIV_VFS_MOUNT_OWNER inside a jail.
- Move security checks to vfs_suser() and deny unmounting and updating
  for jailed root from different jails, etc.

OK'ed by:	rwatson
2007-04-13 23:54:22 +00:00
Nate Lawson
a363f67a81 Restore the locking for the sleep/wakeup to avoid waiting an extra 1 sec
if a race was lost.  We're still single-threaded at this point, but just
be safe for the future.
2007-04-09 21:10:04 +00:00
Nate Lawson
6b1e469ea5 Clean up the root mount and mount wait code. No mutexes are needed here
since a spurious wakeup() is the only possible outcome and this is fine in
the BSD programming model.
2007-04-09 19:23:52 +00:00
Pawel Jakub Dawidek
2eb68d493f Add root_mounted() function that returns true if the root file system is
already mounted.
2007-04-08 23:54:01 +00:00
Pawel Jakub Dawidek
f3a8d2f93c Add security.jail.mount_allowed sysctl, which allows to mount and
unmount jail-friendly file systems from within a jail.
Precisely it grants PRIV_VFS_MOUNT, PRIV_VFS_UNMOUNT and
PRIV_VFS_MOUNT_NONUSER privileges for a jailed super-user.
It is turned off by default.

A jail-friendly file system is a file system which driver registers
itself with VFCF_JAIL flag via VFS_SET(9) API.
The lsvfs(1) command can be used to see which file systems are
jail-friendly ones.

There currently no jail-friendly file systems, ZFS will be the first one.
In the future we may consider marking file systems like nullfs as
jail-friendly.

Reviewed by:	rwatson
2007-04-05 21:03:05 +00:00
Robert Watson
5e3f7694b1 Replace custom file descriptor array sleep lock constructed using a mutex
and flags with an sxlock.  This leads to a significant and measurable
performance improvement as a result of access to shared locking for
frequent lookup operations, reduced general overhead, and reduced overhead
in the event of contention.  All of these are imported for threaded
applications where simultaneous access to a shared file descriptor array
occurs frequently.  Kris has reported 2x-4x transaction rate improvements
on 8-core MySQL benchmarks; smaller improvements can be expected for many
workloads as a result of reduced overhead.

- Generally eliminate the distinction between "fast" and regular
  acquisisition of the filedesc lock; the plan is that they will now all
  be fast.  Change all locking instances to either shared or exclusive
  locks.

- Correct a bug (pointed out by kib) in fdfree() where previously msleep()
  was called without the mutex held; sx_sleep() is now always called with
  the sxlock held exclusively.

- Universally hold the struct file lock over changes to struct file,
  rather than the filedesc lock or no lock.  Always update the f_ops
  field last. A further memory barrier is required here in the future
  (discussed with jhb).

- Improve locking and reference management in linux_at(), which fails to
  properly acquire vnode references before using vnode pointers.  Annotate
  improper use of vn_fullpath(), which will be replaced at a future date.

In fcntl(), we conservatively acquire an exclusive lock, even though in
some cases a shared lock may be sufficient, which should be revisited.
The dropping of the filedesc lock in fdgrowtable() is no longer required
as the sxlock can be held over the sleep operation; we should consider
removing that (pointed out by attilio).

Tested by:	kris
Discussed with:	jhb, kris, attilio, jeff
2007-04-04 09:11:34 +00:00
Pawel Jakub Dawidek
afd894bb12 Add root_mount_wait() function which can be used to wait until the root
file system is mounted. This is useful for kernel modules loaded from
/boot/loader.conf, that have to access file system.
2007-04-03 11:45:28 +00:00
Pawel Jakub Dawidek
5c1c2e82e2 I think the code I'm removing here is completely bogus.
vfs_flags field is used for VFCF_* flags which are given at file system
driver creation time (via VFS_SET(9)) macro.

What this code did was bascially this:

If file system registers itself with VFCF_UNICODE flag (stores file names
as Unicode), it will gain MNT_SOFTDEP flag (UFS soft-updates).

If file system registers itself with VFCF_LOOPBACK flag (aliases some other
mounted FS), it will gain MNT_SUIDDIR flag (special handling of SUID on
dirs).

The latter will be quite dangerous, but those flags are reset later in
vfs_domount().

MFC after:	1 month
2007-04-01 13:08:05 +00:00
Pawel Jakub Dawidek
695919ad9a Make vfs_mount_destroy() and vfs_freeopts() non-static, I'd like to use them. 2007-03-31 22:44:45 +00:00
Pawel Jakub Dawidek
9a2fd584b4 Don't deny unmounting file systems for jailed processes immediately, allow
prison_priv_check() to decide what to do.

This change is suppose not to change current (security) behaviour
in any way.

This change is simlar to the change of PRIV_VFS_MOUNT in previous revision.
2007-03-18 02:39:19 +00:00
Pawel Jakub Dawidek
7533652025 Don't deny mounting for jailed processes immediately, allow
prison_priv_check() to decide what to do.

This change is suppose not to change current (security) behaviour
in any way.

Reviewed by:	rwatson
2007-03-14 13:09:59 +00:00
Pawel Jakub Dawidek
f7d4e990c7 White space nits. 2007-03-14 12:54:10 +00:00
Robert Watson
873fbcd776 Further system call comment cleanup:
- Remove also "MP SAFE" after prior "MPSAFE" pass. (suggested by bde)
- Remove extra blank lines in some cases.
- Add extra blank lines in some cases.
- Remove no-op comments consisting solely of the function name, the word
  "syscall", or the system call name.
- Add punctuation.
- Re-wrap some comments.
2007-03-05 13:10:58 +00:00
Olivier Houchard
38cc2a5caa Make vfs_getopts() set *error to ENOENT if the option wasn't found, so that
consumers don't have to check for both error and the return value (some of
them actually don't do it).

MFC After:	1 week
2007-02-13 01:28:48 +00:00
Craig Rodrigues
2892f3bbfa Add a function vfs_deleteopt() which searches through the vfsoptlist
linked list of mount options by name, and deletes the option if it finds it.
2006-12-16 15:44:03 +00:00
Robert Watson
acd3428b7d Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
specific privilege names to a broad range of privileges.  These may
require some future tweaking.

Sponsored by:           nCircle Network Security, Inc.
Obtained from:          TrustedBSD Project
Discussed on:           arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
                        Alex Lyashkov <umka at sevcity dot net>,
                        Skip Ford <skip dot ford at verizon dot net>,
                        Antoine Brodin <antoine dot brodin at laposte dot net>
2006-11-06 13:42:10 +00:00
Robert Watson
aed5570872 Complete break-out of sys/sys/mac.h into sys/security/mac/mac_framework.h
begun with a repo-copy of mac.h to mac_framework.h.  sys/mac.h now
contains the userspace and user<->kernel API and definitions, with all
in-kernel interfaces moved to mac_framework.h, which is now included
across most of the kernel instead.

This change is the first step in a larger cleanup and sweep of MAC
Framework interfaces in the kernel, and will not be MFC'd.

Obtained from:	TrustedBSD Project
Sponsored by:	SPARTA
2006-10-22 11:52:19 +00:00
Konstantin Belousov
30af71199e Fix the remaining race in the revs. 1.232, 1,233 that could occur during
unmount when mp structure is reused while waiting for coveredvp lock.
Introduce struct mount generation count, increment it on each reuse and
compare the generations before and after obtaining the coveredvp lock.

Reviewed by:	tegge, pjd
Approved by:	pjd (mentor)
MFC after:	2 weeks
2006-10-03 10:47:04 +00:00
Poul-Henning Kamp
f645b0b51c First part of a little cleanup in the calendar/timezone/RTC handling.
Move relevant variables to <sys/clock.h> and fix #includes as necessary.

Use libkern's much more time- & spamce-efficient BCD routines.
2006-10-02 12:59:59 +00:00
Tor Egge
e60c361218 Reduce fluctuations of mnt_flag to allow unlocked readers to get a
slightly more consistent view.
2006-09-26 04:20:09 +00:00
Tor Egge
fba924ce9b Don't restore MNT_QUOTA bit in mnt_flag after a failed mount with
MNT_UPDATE flag, closing a race between nmount() and quotactl().
2006-09-26 04:18:36 +00:00
Tor Egge
a1e363f256 Add mnt_noasync counter to better handle interleaved calls to nmount(),
sync() and sync_fsync() without losing MNT_ASYNC.  Add MNTK_ASYNC flag
which is set only when MNT_ASYNC is set and mnt_noasync is zero, and
check that flag instead of MNT_ASYNC before initiating async io.
2006-09-26 04:15:59 +00:00
Tor Egge
cea9d840d8 Don't restore mnt_kern_flag on failed MNT_UPDATE mount, it can race
with dounmount(), causing loss of MNTK_UNMOUNT flag.
2006-09-26 04:15:04 +00:00