Commit Graph

339 Commits

Author SHA1 Message Date
mckusick
be6aa51161 When the number of dirty buffers rises too high, the buf_daemon runs
to help clean up. After selecting a potential buffer to write, this
patch has it acquire a lock on the vnode that owns the buffer before
trying to write it. The vnode lock is necessary to avoid a race with
some other process holding the vnode locked and trying to flush its
dirty buffers. In particular, if the vnode in question is a snapshot
file, then the race can lead to a deadlock. To avoid slowing down the
buf_daemon, it does a non-blocking lock request when trying to lock
the vnode. If it fails to get the lock it skips over the buffer and
continues down its queue looking for buffers to flush.

Sponsored by:	DARPA & NAI Labs.
2002-10-18 01:29:59 +00:00
phk
c5be3924c3 Remove unused includes.
Clarify the intention of a while();
Move a local variable to avoid potential name-confusion.
2002-09-28 17:46:30 +00:00
phk
1dfc2c167f Be consistent about "static" functions: if the function is marked
static in its prototype, mark it static at the definition too.

Inspired by:    FlexeLint warning #512
2002-09-28 17:15:38 +00:00
phk
107a67d351 Correctly order VI_UNLOCK(), local variables and block comment. 2002-09-28 12:15:44 +00:00
phk
9eadc24323 Make biowait() check bio_error before the BIO_ERROR flag, to propery
catch internal GEOM use of bio_error.

Sponsored by:	DARPA & NAI Labs.
2002-09-26 16:32:14 +00:00
jeff
54956e8ea4 - Lock accesses to v_numoutput.
- Lock calls to gbincore.
2002-09-25 02:11:37 +00:00
phk
1ff0331915 s/Danglish/English/
Some style issues.
Change the timeout to be hz/10 instead of hz.

Brucification by:	bde.
2002-09-15 17:52:35 +00:00
phk
cff87abbac Un-inline the non-trivial "trivial" bio* functions.
Untangle devstat_end_transaction_bio()
2002-09-14 19:34:11 +00:00
njl
0590c43070 Remove all use of vnode->v_tag, replacing with appropriate substitutes.
v_tag is now const char * and should only be used for debugging.

Additionally:
1. All users of VT_NTS now check vfsconf->vf_type VFCF_NETWORK
2. The user of VT_PROCFS now checks for the new flag VV_PROCDEP, which
is propagated by pseudofs to all child vnodes if the fs sets PFS_PROCDEP.

Suggested by:   phk
Reviewed by:    bde, rwatson (earlier version)
2002-09-14 09:02:28 +00:00
phk
725daf0b2d Oops, broke the build there. Uninline biodone() now that it is non-trivial.
Introduce biowait() function.  Currently there is a race condition and the
mitigation is a timeout/retry.  It is not obvious what kind of locking (if any)
is suitable for BIO_DONE, since the majority of users take are of this
themselves, and only a few places actually rely on the wakeup.

Sponsored by: DARPA & NAI Labs.
2002-09-13 11:28:31 +00:00
peter
c3bdd669c3 Change hw.physmem and hw.usermem to unsigned long like they used to be
in the original hardwired sysctl implementation.

The buf size calculator still overflows an integer on machines with large
KVA (eg: ia64) where the number of pages does not fit into an int.  Use
'long' there.

Change Maxmem and physmem and related variables to 'long', mostly for
completeness.  Machines are not likely to overflow 'int' pages in the
near term, but then again, 640K ought to be enough for anybody.  This
comes for free on 32 bit machines, so why not?
2002-08-30 04:04:37 +00:00
charnier
7dd9d47059 Replace various spelling with FALLTHROUGH which is lint()able 2002-08-25 13:23:09 +00:00
jeff
02517b6731 - Replace v_flag with v_iflag and v_vflag
- v_vflag is protected by the vnode lock and is used when synchronization
   with VOP calls is needed.
 - v_iflag is protected by interlock and is used for dealing with vnode
   management issues.  These flags include X/O LOCK, FREE, DOOMED, etc.
 - All accesses to v_iflag and v_vflag have either been locked or marked with
   mp_fixme's.
 - Many ASSERT_VOP_LOCKED calls have been added where the locking was not
   clear.
 - Many functions in vfs_subr.c were restructured to provide for stronger
   locking.

Idea stolen from:	BSD/OS
2002-08-04 10:29:36 +00:00
alc
5674611fb4 o Convert two instances of vm_page_sleep_busy() to vm_page_sleep_if_busy()
with appropriate page queue locking.
2002-08-03 18:59:19 +00:00
alc
88e0310b1e o Acquire the page queues lock before calling vm_page_io_finish().
o Assert that the page queues lock is held in vm_page_io_finish().
2002-08-01 17:57:42 +00:00
alc
14df04dfaf o Replace vm_page_sleep_busy() with vm_page_sleep_if_busy()
in vfs_busy_pages().
2002-07-30 20:41:10 +00:00
alc
1926ab155f o Use vm_page_alloc(... | VM_ALLOC_WIRED) in place of vm_page_wire(). 2002-07-19 19:35:06 +00:00
mckusick
b44cb5787c Add support to UFS2 to provide storage for extended attributes.
As this code is not actually used by any of the existing
interfaces, it seems unlikely to break anything (famous
last words).

The internal kernel interface to manipulate these attributes
is invoked using two new IO_ flags: IO_NORMAL and IO_EXT.
These flags may be specified in the ioflags word of VOP_READ,
VOP_WRITE, and VOP_TRUNCATE. Specifying IO_NORMAL means that
you want to do I/O to the normal data part of the file and
IO_EXT means that you want to do I/O to the extended attributes
part of the file. IO_NORMAL and IO_EXT are mutually exclusive
for VOP_READ and VOP_WRITE, but may be specified individually
or together in the case of VOP_TRUNCATE. For example, when
removing a file, VOP_TRUNCATE is called with both IO_NORMAL
and IO_EXT set. For backward compatibility, if neither IO_NORMAL
nor IO_EXT is set, then IO_NORMAL is assumed.

Note that the BA_ and IO_ flags have been `merged' so that they
may both be used in the same flags word. This merger is possible
by assigning the IO_ flags to the low sixteen bits and the BA_
flags the high sixteen bits. This works because the high sixteen
bits of the IO_ word is reserved for read-ahead and help with
write clustering so will never be used for flags. This merge
lets us get away from code of the form:

        if (ioflags & IO_SYNC)
                flags |= BA_SYNC;

For the future, I have considered adding a new field to the
vattr structure, va_extsize. This addition could then be
exported through the stat structure to allow applications to
find out the size of the extended attribute storage and also
would provide a more standard interface for truncating them
(via VOP_SETATTR rather than VOP_TRUNCATE).

I am also contemplating adding a pathconf parameter (for
concreteness, lets call it _PC_MAX_EXTSIZE) which would
let an application determine the maximum size of the extended
atribute storage.

Sponsored by:	DARPA & NAI Labs.
2002-07-19 07:29:39 +00:00
alc
e650551ab9 o Lock page queue accesses by vm_page_wire(). 2002-07-14 19:45:46 +00:00
alc
a23831a538 o Lock some page queue accesses, in particular, those by vm_page_unwire(). 2002-07-13 20:13:34 +00:00
dillon
da4e111a55 Replace the global buffer hash table with per-vnode splay trees using a
methodology similar to the vm_map_entry splay and the VM splay that Alan
Cox is working on.  Extensive testing has appeared to have shown no
increase in overhead.

Disadvantages
    Dirties more cache lines during lookups.

    Not as fast as a hash table lookup (but still N log N and optimal
    when there is locality of reference).

Advantages
    vnode->v_dirtyblkhd is now perfectly sorted, making fsync/sync/filesystem
    syncer operate more efficiently.

    I get to rip out all the old hacks (some of which were mine) that tried
    to keep the v_dirtyblkhd tailq sorted.

    The per-vnode splay tree should be easier to lock / SMPng pushdown on
    vnodes will be easier.

    This commit along with another that Alan is working on for the VM page
    global hash table will allow me to implement ranged fsync(), optimize
    server-side nfs commit rpcs, and implement partial syncs by the
    filesystem syncer (aka filesystem syncer would detect that someone is
    trying to get the vnode lock, remembers its place, and skip to the
    next vnode).

Note that the buffer cache splay is somewhat more complex then other splays
due to special handling of background bitmap writes (multiple buffers with
the same lblkno in the same vnode), and B_INVAL discontinuities between the
old hash table and the existence of the buffer on the v_cleanblkhd list.

Suggested by: alc
2002-07-10 17:02:32 +00:00
bde
401e8fb129 Fixed some printf format errors (one new one reported by gcc and 3 nearby
old ones not reported by gcc).  This helps unbreak LINT.
2002-07-08 12:21:11 +00:00
jeff
5d7805963e Add two asserts that prove & document getblk and geteblk's behavior of
returning locked bufs.
2002-07-07 05:27:08 +00:00
jeff
f1b0400267 Fix a mistake in my last commit. Don't grab an extra reference to the object
in bp->b_object.
2002-07-06 21:27:20 +00:00
jeff
0dd7645264 Fixup uses of GETVOBJECT.
- Cache a pointer to the vnode's object in the buf.
 - Hold a reference to that object in addition to the vnode's reference just
   to be consistent.
 - Cleanup code that got the object indirectly through the vp and VOP calls.

This fixes at least one case where we were calling GETVOBJECT without a lock.
It also avoids an expensive layered call at the cost of another pointer in
struct buf.
2002-07-06 08:59:52 +00:00
mux
abb73c48ca More 64 bits platforms warning fixes.
Reviewed by:	rwatson
2002-06-23 18:32:39 +00:00
dillon
0af4a7d8da Fix a bug in vfs_bio_clrbuf(). The single-page-clrbuf optimization was
improperly clearing more then just the invalid portions of the page.  (This
bug is not known to have been triggered by anything).

Submitted by:	tegge
MFC after:	7 days
2002-06-22 19:09:35 +00:00
mckusick
88d85c15ef This commit adds basic support for the UFS2 filesystem. The UFS2
filesystem expands the inode to 256 bytes to make space for 64-bit
block pointers. It also adds a file-creation time field, an ability
to use jumbo blocks per inode to allow extent like pointer density,
and space for extended attributes (up to twice the filesystem block
size worth of attributes, e.g., on a 16K filesystem, there is space
for 32K of attributes). UFS2 fully supports and runs existing UFS1
filesystems. New filesystems built using newfs can be built in either
UFS1 or UFS2 format using the -O option. In this commit UFS1 is
the default format, so if you want to build UFS2 format filesystems,
you must specify -O 2. This default will be changed to UFS2 when
UFS2 proves itself to be stable. In this commit the boot code for
reading UFS2 filesystems is not compiled (see /sys/boot/common/ufsread.c)
as there is insufficient space in the boot block. Once the size of the
boot block is increased, this code can be defined.

Things to note: the definition of SBSIZE has changed to SBLOCKSIZE.
The header file <ufs/ufs/dinode.h> must be included before
<ufs/ffs/fs.h> so as to get the definitions of ufs2_daddr_t and
ufs_lbn_t.

Still TODO:
Verify that the first level bootstraps work for all the architectures.
Convert the utility ffsinfo to understand UFS2 and test growfs.
Add support for the extended attribute storage. Update soft updates
to ensure integrity of extended attribute storage. Switch the
current extended attribute interfaces to use the extended attribute
storage. Add the extent like functionality (framework is there,
but is currently never used).

Sponsored by: DARPA & NAI Labs.
Reviewed by:	Poul-Henning Kamp <phk@freebsd.org>
2002-06-21 06:18:05 +00:00
phk
b98dc1ffce Use "bwrbg" as description when we sleep for background writing,
"biord" was misleading in every possible way.
2002-06-06 08:56:10 +00:00
phk
536c2f0f78 Remove a six year old undocumented #ifdef : NO_B_MALLOC. 2002-05-04 19:24:55 +00:00
jhb
db9aa81e23 Change callers of mtx_init() to pass in an appropriate lock type name. In
most cases NULL is passed, but in some cases such as network driver locks
(which use the MTX_NETWORK_LOCK macro) and UMA zone locks, a name is used.

Tested on:	i386, alpha, sparc64
2002-04-04 21:03:38 +00:00
dillon
9a85737b15 brelse() was improperly clearing B_DELWRI in the B_DELWRI|B_INVAL case
without removing the buffer from the vnode's dirty buffer list, which
can result in a panic in NFS.  Replaced the code with a call to bundirty()
which deals with it properly.

PR:		kern/36108, kern/36174
Submitted by:	various people
Special mention: to Danny Schales <dan@coes.LaTech.edu> for providing a core dump that helped me track this down.
MFC after:	1 day
2002-04-03 00:17:36 +00:00
alfred
357e37e023 Remove __P. 2002-03-19 21:25:46 +00:00
bde
df8144b98e Fixed some printf format errors (hopefully all of the remaining daddr64_t
ones for GENERIC, and all others on the same line as those).  Reformat
the printfs if necessary to avoid new long lones or old format printf
errors.
2002-03-19 04:09:21 +00:00
jake
34dcf8975d Convert all pmap_kenter/pmap_kremove pairs in MI code to use pmap_qenter/
pmap_qremove.  pmap_kenter is not safe to use in MI code because it is not
guaranteed to flush the mapping from the tlb on all cpus.  If the process
in question is preempted and migrates cpus between the call to pmap_kenter
and pmap_kremove, the original cpu will be left with stale mappings in its
tlb.  This is currently not a problem for i386 because we do not use PG_G on
SMP, and thus all mappings are flushed from the tlb on context switches, not
just user mappings.  This is not the case on all architectures, and if PG_G
is to be used with SMP on i386 it will be a problem.  This was committed by
peter earlier as part of his fine grained tlb shootdown work for i386, which
was backed out for other reasons.

Reviewed by:	peter
2002-03-17 00:56:41 +00:00
mckusick
e929f2e4f0 Introduce the new 64-bit size disk block, daddr64_t. Change
the bio and buffer structures to have daddr64_t bio_pblkno,
b_blkno, and b_lblkno fields which allows access to disks
larger than a Terabyte in size. This change also requires
that the VOP_BMAP vnode operation accept and return daddr64_t
blocks. This delta should not affect system operation in
any way. It merely sets up the necessary interfaces to allow
the development of disk drivers that work with these larger
disk block addresses. It also allows for the development of
UFS2 which will use 64-bit block addresses.
2002-03-15 18:49:47 +00:00
alfred
b0fd50345a Giant pushdown for read/write/pread/pwrite syscalls.
kern/kern_descrip.c:
Aquire Giant in fdrop_locked when file refcount hits zero, this removes
the requirement for the caller to own Giant for the most part.

kern/kern_ktrace.c:
Aquire Giant in ktrgenio, simplifies locking in upper read/write syscalls.

kern/vfs_bio.c:
Aquire Giant in bwillwrite if needed.

kern/sys_generic.c
Giant pushdown, remove Giant for:
   read, pread, write and pwrite.
readv and writev aren't done yet because of the possible malloc calls
for iov to uio processing.

kern/sys_socket.c
Grab giant in the socket fo_read/write functions.

kern/vfs_vnops.c
Grab giant in the vnode fo_read/write functions.
2002-03-15 08:03:46 +00:00
eivind
e97f2e798c * Move bswlist declaration and initialization from kern/vfs_bio.c to
vm/vm_pager.c, which is the only place it is used.
* Make the QUEUE_* definitions and bufqueues local to vfs_bio.c.
* constify buf_wmesg.
2002-03-05 18:20:58 +00:00
eivind
05c20bbea2 Document all functions, global and static variables, and sysctls.
Includes some minor whitespace changes, and re-ordering to be able to document
properly (e.g, grouping of variables and the SYSCTL macro calls for them, where
the documentation has been added.)

Reviewed by:	phk (but all errors are mine)
2002-03-05 15:38:49 +00:00
peter
f2dee2e96f Back out all the pmap related stuff I've touched over the last few days.
There is some unresolved badness that has been eluding me, particularly
affecting uniprocessor kernels.  Turning off PG_G helped (which is a bad
sign) but didn't solve it entirely.  Userland programs still crashed.
2002-02-27 09:51:33 +00:00
peter
2051cd9c72 Jake further reduced IPI shootdowns on sparc64 in loops by using ranged
shootdowns in a couple of key places.  Do the same for i386.  This also
hides some physical addresses from higher levels and has it use the
generic vm_page_t's instead.  This will help for PAE down the road.

Obtained from:	jake (MI code, suggestions for MD part)
2002-02-27 02:14:58 +00:00
phk
b9b775cf13 GC: BIO_ORDERED, various infrastructure dealing with BIO_ORDERED. 2002-02-22 09:26:35 +00:00
phk
62d248fb9e Replace bowrite() with BUF_WRITE in ufs.
Remove bowrite(), it is now unused.

This is the first step in getting entirely rid of BIO_ORDERED which is
a generally accepted evil thing.

Approved by:	mckusick
2002-02-22 09:03:00 +00:00
dillon
8abd6168f2 GC P_BUFEXHAUST leftovers, we've had a new mechanism to avoid buffer
cache lockups for over a year now.

MFC after:		0 days
2002-01-31 18:39:44 +00:00
dillon
cd4d323ad3 This fixes a large number of bugs in our NFS client side code. A recent
commit by Kirk also fixed a softupdates bug that could easily be triggered
by server side NFS.

	* An edge case with shared R+W mmap()'s and truncate whereby
	  the system would inappropriately clear the dirty bits on
	  still-dirty data.  (applicable to all filesystems)

	  THIS FIX TEMPORARILY DISABLED PENDING FURTHER TESTING.
	  see vm/vm_page.c line 1641

	* The straddle case for VM pages and buffer cache buffers when
	  truncating.  (applicable to NFS client side)

	* Possible SMP database corruption due to vm_pager_unmap_page()
	  not clearing the TLB for the other cpu's.  (applicable to NFS
	  client side but could effect all filesystems).  Note: not
	  considered serious since the corruption occurs beyond the file
	  EOF.

	* When flusing a dirty buffer due to B_CACHE getting cleared,
	  we were accidently setting B_CACHE again (that is, bwrite() sets
	  B_CACHE), when we really want it to stay clear after the write
	  is complete.  This resulted in a corrupt buffer.  (applicable
	  to all filesystems but probably only triggered by NFS)

	* We have to call vtruncbuf() when ftruncate()ing to remove
	  any buffer cache buffers.  This is still tentitive, I may
	  be able to remove it due to the second bug fix.  (applicable
	  to NFS client side)

	* vnode_pager_setsize() race against nfs_vinvalbuf()... we have
	  to set n_size before calling nfs_vinvalbuf or the NFS code
	  may recursively vnode_pager_setsize() to the original value
	  before the truncate.  This is what was causing the user mmap
	  bus faults in the nfs tester program.  (applicable to NFS
	  client side)

	* Fix to softupdates (see ufs/ffs/ffs_inode.c 1.73, commit made
	  by Kirk).

Testing program written by: Avadis Tevanian, Jr.
Testing program supplied by: jkh / Apple (see Dec2001 posting to freebsd-hackers with Subject 'NFS: How to make FreeBS fall on its face in one easy step')
MFC after:	1 week
2001-12-14 01:16:57 +00:00
dillon
6e9238ff3f The nbuf calculation was assuming that PAGE_SIZE = 4096 bytes, which is
bogus.  The calculation has been adjusted to use units of kilobytes.

Noticed by: Chad David <davidc@acns.ab.ca>
MFC after:	1 week
2001-12-08 20:37:08 +00:00
dillon
08792e81f7 Placemark an interrupt race in -current which is currently protected by
Giant.  -stable will get spl*() fixes for the race.

Reported by: Rob Anderson <rob@isilon.com>
MFC after:	0 days
2001-11-08 18:09:18 +00:00
dillon
1147eaf58a Implement IO_NOWDRAIN and B_NOWDRAIN - prevents the buffer cache from blocking
in wdrain during a write.  This flag needs to be used in devices whos
strategy routines turn-around and issue another high level I/O, such as
when MD turns around and issues a VOP_WRITE to vnode backing store, in order
to avoid deadlocking the dirty buffer draining code.

Remove a vprintf() warning from MD when the backing vnode is found to be
in-use.  The syncer of buf_daemon could be flushing the backing vnode at
the time of an MD operation so the warning is not correct.

MFC after:	1 week
2001-11-05 18:48:54 +00:00
dillon
c6710f54b0 Documentation
MFC after:	1 day
2001-10-21 06:26:55 +00:00
jhb
4806d88677 Change the kernel's ucred API as follows:
- crhold() returns a reference to the ucred whose refcount it bumps.
- crcopy() now simply copies the credentials from one credential to
  another and has no return value.
- a new crshared() primitive is added which returns true if a ucred's
  refcount is > 1 and false (0) otherwise.
2001-10-11 23:38:17 +00:00