Commit Graph

201 Commits

Author SHA1 Message Date
ae
7f1d0d3f37 Include sys/sbuf.h directly. 2011-07-11 05:19:28 +00:00
mdf
3d3b036f95 Move the ZERO_REGION_SIZE to a machine-dependent file, as on many
architectures (i386, for example) the virtual memory space may be
constrained enough that 2MB is a large chunk.  Use 64K for arches
other than amd64 and ia64, with special handling for sparc64 due to
differing hardware.

Also commit the comment changes to kmem_init_zero_region() that I
missed due to not saving the file.  (Darn the unfamiliar development
environment).

Arch maintainers, please feel free to adjust ZERO_REGION_SIZE as you
see fit.

Requested by:	alc
MFC after:	1 week
MFC with:	r221853
2011-05-13 19:35:01 +00:00
mdf
9465c34001 Usa a globally visible region of zeros for both /dev/zero and the md
device.  There are likely other kernel uses of "blob of zeros" than can
be converted.

Reviewed by:	alc
MFC after:	1 week
2011-05-13 18:48:00 +00:00
des
f99737eb7b Implement BIO_DELETE for vnode devices by simply overwriting the deleted
sectors with all-zeroes.

The zeroes come from a static buffer; null(4) uses a dynamic buffer for
the same purpose (for /dev/zero).  It might be a good idea to have a
static, shared, read-only all-zeroes page somewhere in the kernel that
md(4), null(4) and any other code that needs zeroes could use.

Reviewed by:	kib
MFC after:	3 weeks
2011-04-29 21:18:41 +00:00
marcel
9e4a891196 Use the preload_fetch_addr() and preload_fetch_size() convenience
functions and only create the MD device when we have a non-zero
pointer and size.

Sponsored by: Juniper Networks
2011-02-09 19:31:10 +00:00
kib
83917be69e Add support for BIO_DELETE on swap-backed md(4). In the case of BIO_DELETE
covering the whole page, free the page. Otherwise, clear the region and
mark it clean. Not marking the page dirty could reinstantiate cleared
data, but it is allowed by BIO_DELETE specification and saves unneeded
write to swap.

Reviewed by:	alc
Tested by:	pho
MFC after:	2 weeks
2011-01-27 16:10:25 +00:00
kib
25f8e1e95f Bio shall not be accessed after g_io_deliver(9).
Reported and tested by:	pho
Reviewed by:	ae, phk
MFC after:	1 week
2011-01-25 14:00:30 +00:00
kib
dc5706ffe3 Add missed ().
Noted by:	alc
MFC after:	3 days
2011-01-19 16:48:07 +00:00
alc
6614c76cb4 There is no point in calling vm_object_set_writeable_dirty() on an object
that is definitively known to be swap backed since its only effects are on
vnode-backed objects.

Reviewed by:	kib
2011-01-19 15:43:54 +00:00
kib
cbd7f9d931 Add reporting of GEOM::candelete BIO_GETATTR for md(4) and geom_disk(4).
Non-zero value of attribute means that device supports BIO_DELETE.

Suggested and reviewed by:	pjd
Tested by:	pho
MFC after:	1 week
2010-12-29 12:11:07 +00:00
kib
41c444747f Add sysctl vm.md_malloc_wait, non-zero value of which switches malloc-backed
md(4) to using M_WAITOK malloc calls.

M_NOWAITOK allocations may fail when enough memory could be freed, but not
immediately. E.g. SU UFS becomes quite unhappy when metadata write return
error, that would happen for failed malloc() call.

Reported and tested by:	pho
MFC after:	1 week
2010-12-29 11:39:15 +00:00
marcel
9d3ef80ee1 Allow the MDIOCATTACH ioctl operation to originate from within the kernel.
To protect against malicious software, we demand that the file name is at
a particular location (i.e. appended to the mdio structure) for it to be
treated as in-kernel.
2010-10-18 04:26:32 +00:00
jh
2aedf3a2fe - Remove some extra white space.
- Wrap g_md_dumpconf() prototype to 80 columns.
2010-07-26 10:37:14 +00:00
jh
1a7a2445e6 Convert md(4) to use alloc_unr(9) and alloc_unr_specific(9) for unit
number allocation. The old approach had some problems such as it allowed
an overflow to occur in the unit number calculation.

PR:		kern/122288
2010-07-22 10:24:28 +00:00
kib
cc677e94f4 Calculate nshift only once.
Also noted by:	avg
MFC after:	1 week
2010-07-06 18:22:57 +00:00
alc
c907b418fb Eliminate unnecessary page queues locking. 2010-06-15 18:37:31 +00:00
kib
44c384aeff Lock the page around vm_page_activate() and vm_page_deactivate() calls
where it was missed. The wrapped fragments now protect wire_count with
page lock.

Reviewed by:	alc
2010-05-03 20:31:13 +00:00
trasz
e9d23bc38a Fix panic on invalid 'mdconfig -at preload' usage.
PR:		kern/80136
2010-02-27 10:41:30 +00:00
antoine
bfd388c026 (S)LIST_HEAD_INITIALIZER takes a (S)LIST_HEAD as an argument.
Fix some wrong usages.
Note: this does not affect generated binaries as this argument is not used.

PR:		137213
Submitted by:	Eygene Ryabinkin (initial version)
MFC after:	1 month
2009-12-28 22:56:30 +00:00
kib
fa686c638e Implement global and per-uid accounting of the anonymous memory. Add
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)
2009-06-23 20:45:22 +00:00
marcel
8b09116a5a Add cpu_flush_dcache() for use after non-DMA based I/O so that a
possible future I-cache coherency operation can succeed. On ARM
for example the L1 cache can be (is) virtually mapped, which
means that any I/O that uses temporary mappings will not see the
I-cache made coherent. On ia64 a similar behaviour has been
observed. By flushing the D-cache, execution of binaries backed
by md(4) and/or NFS work reliably.
For Book-E (powerpc), execution over NFS exhibits SIGILL once in
a while as well, though cpu_flush_dcache() hasn't been implemented
yet.

Doing an explicit D-cache flush as part of the non-DMA based I/O
read operation eliminates the need to do it as part of the
I-cache coherency operation itself and as such avoids pessimizing
the DMA-based I/O read operations for which D-cache are already
flushed/invalidated. It also allows future optimizations whereby
the bcopy() followed by the D-cache flush can be integrated in a
single operation, which could be implemented using on-chips DMA
engines, by-passing the D-cache altogether.
2009-05-18 18:37:18 +00:00
jhb
520acdaf69 Add a new internal mount flag (MNTK_EXTENDED_SHARED) to indicate that a
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
2009-03-11 14:13:47 +00:00
alc
737844bb9e Remove unnecessary page queues locking around vm_page_wakeup(). (This
change is applicable to RELENG_7 but not RELENG_6.)

MFC after:	1 week
2009-02-22 02:50:31 +00:00
trasz
81e2127caa Add the possibility to specify "-o force" with "mdconfig -du".
Reviewed by:	scottl
Approved by:	rwatson (mentor)
Sponsored by:	FreeBSD Foundation
2009-01-10 17:17:18 +00:00
trasz
4039bb7c82 Fix forced mdconfig -du. E.g. the following would previously
result in panic:

mdconfig -af blah.img -o force
mount /dev/md0 /mnt
mdconfig -du 0

Reviewed by:	scottl
Approved by:	rwatson (mentor)
Sponsored by:	FreeBSD Foundation
2008-12-16 20:59:27 +00:00
attilio
dbf35e279f Decontextualize the couplet VOP_GETATTR / VOP_SETATTR as the passed thread
was always curthread and totally unuseful.

Tested by: Giovanni Trematerra <giovanni dot trematerra at gmail dot com>
2008-08-28 15:23:18 +00:00
ed
5de6a45e07 Remove the distinction between device minor and unit numbers.
Even though we got rid of device major numbers some time ago, device
drivers still need to provide unique device minor numbers to make_dev().
These numbers are only used inside the kernel. They are not related to
device major and minor numbers which are visible in devfs. These are
actually based on the inode number of the device.

It would eventually be nice to remove minor numbers entirely, but we
don't want to be too agressive here.

Because the 8-15 bits of the device number field (si_drv0) are still
reserved for the major number, there is no 1:1 mapping of the device
minor and unit numbers. Because this is now unused, remove the
restrictions on these numbers.

The MAXMAJOR definition was actually used for two purposes. It was used
to convert both the userspace and kernelspace device numbers to their
major/minor pair, which is why it is now named UMINORMASK.

minor2unit() and unit2minor() have now become useless. Both minor() and
dev2unit() now serve the same purpose. We should eventually remove some
of them, at least turning them into macro's. If devfs would become
completely minor number unaware, we could consider using si_drv0 directly,
just like si_drv1 and si_drv2.

Approved by:	philip (mentor)
2008-05-29 12:50:46 +00:00
philip
a5ef2c95a1 Zero sc->vnode if mdsetcred() fails.
This fixes the panic which happens when mdcreate_vnode() calls vn_close()
and mddestroy() calls it again further down the error handling path.

Reviewed by:	kris, kib
MFC after:	3 days
2008-02-28 18:31:54 +00:00
attilio
71b7824213 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
18d0a0dd51 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
sobomax
e70726e1e8 Put back devstat support that was lost during GEOM transition. Initially,
I've tried to move md(4) to use geom_disk class, like real disks do, but
this requires major rework of some of the existing features such as
configuration dumping for example. Therefore just putting devstat support
directly into md(4) seems to be optimal solution.

Now you can see md(4) stats in `systat -vm' again.

MFC after:	2 weeks
2007-11-07 22:47:41 +00:00
julian
51d643caa6 Rename the kthread_xxx (e.g. kthread_create()) calls
to kproc_xxx as they actually make whole processes.
Thos makes way for us to add REAL kthread_create() and friends
that actually make theads. it turns out that most of these
calls actually end up being moved back to the thread version
when it's added. but we need to make this cosmetic change first.

I'd LOVE to do this rename in 7.0  so that we can eventually MFC the
new kthread_xxx() calls.
2007-10-20 23:23:23 +00:00
jeff
91d1501790 Commit 14/14 of sched_lock decomposition.
- Use thread_lock() rather than sched_lock for per-thread scheduling
   sychronization.
 - Use the per-process spinlock rather than the sched_lock for per-process
   scheduling synchronization.

Tested by:      kris, current@
Tested on:      i386, amd64, ULE, 4BSD, libthr, libkse, PREEMPTION, etc.
Discussed with: kris, attilio, kmacy, jhb, julian, bde (small parts each)
2007-06-05 00:00:57 +00:00
kib
f13486a222 Revert UF_OPENING workaround for CURRENT.
Change the VOP_OPEN(), vn_open() vnode operation and d_fdopen() cdev operation
argument from being file descriptor index into the pointer to struct file.

Proposed and reviewed by:	jhb
Reviewed by:	daichi (unionfs)
Approved by:	re (kensmith)
2007-05-31 11:51:53 +00:00
kib
e7cdcb3240 Resolve two deadlocks that could be caused by busy md device backed
by vnode. Allow for md thread and the thread that owns lock on vnode
backing the md device to do the write even when runningbufspace is
exhausted.

Tested by:	Peter Holm
Reviewed by:	tegge
MFC after:	2 weeks
2006-12-14 11:34:07 +00:00
pjd
da7da1722d Style nits. 2006-11-01 18:59:06 +00:00
pjd
6058d96715 Fix md(4) panic which occurs when I/O request different than
BIO_READ/BIO_WRITE is sent to vnode-backed provider (BIO_DELETE or
BIO_FLUSH).

Reported by:	ceri

Add support for BIO_FLUSH to vnode-backed md(4) devices based on
VOP_FSYNC().
2006-11-01 18:56:18 +00:00
jhb
63f561c624 - Conditionally acquire Giant in mdstart_vnode(), mdcreate_vnode(), and
mddestroy() only if the file is from a non-MPSAFE VFS.
- No longer unconditionally hold Giant in the md kthread for vnode-backed
  kthreads.
- Improve the handling of the thread exit race when destroying an md
  device.
2006-03-28 21:25:11 +00:00
wkoszek
2a5afd7475 Teach md(4) and mdconfig(8) how to understand XML. Right now there won't be
a problem with listing large number of md(4) devices. Either 'list' or
'query' mode uses XML.

Additionally, new functionality was introduced. It's possible to pass
multiple devices to -u:

	# ./mdconfig -l -u md0,md1

Approved by:	cognet (mentor)
2006-03-26 23:21:11 +00:00
luigi
fc2a9f9e7a make sure that the start and end preloaded MFS markers are
in contiguous strings, and that the compiler does not optimize them
away because it thinks they are unused.
2006-01-31 13:35:30 +00:00
pjd
4b80a65bfe Call NDFREE() only when vn_open() succeeded.
MFC after:	3 days
2006-01-27 11:27:55 +00:00
maxim
df025adb58 o Fix typos in the comments.
Submitted by:	Wojciech A. Koszek
2005-12-28 15:18:18 +00:00
rwatson
be4f357149 Normalize a significant number of kernel malloc type names:
- Prefer '_' to ' ', as it results in more easily parsed results in
  memory monitoring tools such as vmstat.

- Remove punctuation that is incompatible with using memory type names
  as file names, such as '/' characters.

- Disambiguate some collisions by adding subsystem prefixes to some
  memory types.

- Generally prefer lower case to upper case.

- If the same type is defined in multiple architecture directories,
  attempt to use the same name in additional cases.

Not all instances were caught in this change, so more work is required to
finish this conversion.  Similar changes are required for UMA zone names.
2005-10-31 15:41:29 +00:00
phk
a3fbbe3447 Make sure that the worker thread knows the type early enough to
grab Giant for vnode backing.

Found by:	pho & tegge
2005-10-06 19:47:04 +00:00
phk
5376d97a97 Fix configuration locking in MD.
Remove  md_mtx.

Remove GIANT from the mdctl device driver and avoid DROP_GIANT,
PICKUP_GIANT and geom events since we can call into GEOM directly
now.

Pick up Giant around vn_close().

Apply an exclusive sx around mdctls ioctl and preloading to protect
lists etc..

Don't initialize our lock (md_mtx or md_sx) from a
SYSINIT when there is a perfectly good pair of _fini/_init
functions to do it from.

Prune any final fractional sector from the mediasize to
keep GEOM happy.

Cleanups:

Unify MDIOVERSION check in (x)mdctlioctl()

Add pointer to start() routine to softc to eliminate a switch{}

Inline guts of mddetach().

Always pass error pointer to mdnew(), simplify implementation.
2005-09-19 06:55:27 +00:00
phk
fd5205fdd9 Do not destroy the queue mutex until the thread is done with it. 2005-09-11 12:35:32 +00:00
pjd
06122c40eb - Add md_mtx lock to protect ID number and list of devices.
- Always check mdnew() return value, as even in !autounit case
  kthread_create() can fail.

Those two changes fix serval panics provked by simple stress test.

Tested by:	Kris The BugMagnet
MFC after:	3 days
2005-08-31 19:45:11 +00:00
csjp
faafaf70f1 Ensure that file flags such as schg, sappnd (and others) are honored
by md(4). Before this change, it was possible to by-pass these flags
by creating memory disks which used a file as a backing store and
writing to the device.

This was discussed by the security team, and although this is problematic,
it was decided that it was not critical as we never guarantee that root will
be restricted.

This change implements the following behavior changes:

-If the user specifies the readonly flag, unset write operations before
 opening the file. If the FWRITE mask is unset, the device will be
 created with the MD_READONLY mask set. (readonly)
-Add a check in g_md_access which checks to see if the MD_READONLY mask
 is set, if so return EROFS
-Do not gracefully downgrade access modes without telling the user. Instead
 make the user specify their intentions for the device (assuming the file is
 read only). This seems like the more correct way to handle things.

This is a RELENG_6 candidate.

PR:		kern/84635
Reviewed by:	phk
2005-08-17 01:24:55 +00:00
alc
13e88b41ba Request a CPU private mapping from sf_buf_alloc(). If the swap-backed
memory disk is larger than the number of available sf_bufs, this improves
performance on SMPs by eliminating interprocessor TLB shootdowns.  For
example, with 6656 sf_bufs, the default on my test machine, and a 256MB
swap-backed memory disk, I see the command
"dd if=/dev/md0 of=/dev/null bs=64k" achieve ~489MB/sec with the default,
shared mappings, and ~587MB/sec with CPU private mappings.
2005-02-13 21:51:50 +00:00
phk
237e3ac2e9 Use MAXMINOR 2005-01-29 16:50:04 +00:00