Commit Graph

958 Commits

Author SHA1 Message Date
Nate Lawson
86ed6d45ac Remove any VOP_PRINT that redundantly prints the tag.
Move lockmgr_printinfo() into vprint() for everyone's benefit.

Suggested by: bde
2002-09-18 20:42:04 +00:00
Nate Lawson
06be2aaa83 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
Bruce Evans
d3a7b5e70e vfs_syscalls.c:
Changed rename(2) to follow the letter of the POSIX spec.  POSIX
requires rename() to have no effect if its args "resolve to the same
existing file".  I think "file" can only reasonably be read as referring
to the inode, although the rationale and "resolve" seem to say that
sameness is at the level of (resolved) directory entries.

ext2fs_vnops.c, ufs_vnops.c:
Replaced code that gave the historical BSD behaviour of removing one
link name by checks that this code is now unreachable.  This fixes
some races.  All vnodes needed to be unlocked for the removal, and
locking at another level using something like IN_RENAME was not even
attempted, so it was possible for rename(x, y) to return with both x
and y removed even without any unlink(2) syscalls (one process can
remove x using rename(x, y) and another process can remove y using
rename(y, x)).

Prodded by:	alfred
MFC after:	8 weeks
PR:		42617
2002-09-10 11:09:13 +00:00
Poul-Henning Kamp
0e168822b2 Implement the VOP_OPENEXTATTR() and VOP_CLOSEEXTATTR() methods.
Use extattr_check_cred() to check access to EAs.

This is still a WIP.

Sponsored by:   DARPA & NAI Labs.
2002-09-05 20:59:42 +00:00
Poul-Henning Kamp
190a4963d0 Use canonical extattr_check_cred() instead of private implementation of the
same policy.

Sponsored by:	DARPA & NAI Labs.
2002-09-05 20:39:36 +00:00
Poul-Henning Kamp
04205dc4be Fix credentials check: do not leak ENOATTR until we know if they're
supposed to know.

Sponsored by:	DARPA & NAI Labs.
2002-09-05 20:28:24 +00:00
Bruce Evans
8f767abf71 Include <sys/malloc.h> instead of depending on namespace pollution 2
layers deep in <sys/proc.h> or <sys/vnode.h>.

Include <sys/vmmeter.h> instead of depending on namespace pollution in
<sys/pcpu.h>.

Sorted includes as much as possible.
2002-09-05 09:43:24 +00:00
Robert Watson
2fc6567e9a Since we have vp and td cached in local variables, use those instead
of derefencing the VOP arguments again when calling the UFS code.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, NAI Labs
2002-09-01 16:06:40 +00:00
Poul-Henning Kamp
d0e9b8dbc4 Correctly handle setting, getting and deleting EA's with zero length content.
Sponsored by:	DARPA & NAI Labs.
2002-08-30 08:57:09 +00:00
Philippe Charnier
93b0017f88 Replace various spelling with FALLTHROUGH which is lint()able 2002-08-25 13:23:09 +00:00
Alan Cox
fff6062ab6 o Retire vm_page_zero_fill() and vm_page_zero_fill_area(). Ever since
pmap_zero_page() and pmap_zero_page_area() were modified to accept
   a struct vm_page * instead of a physical address, vm_page_zero_fill()
   and vm_page_zero_fill_area() have served no purpose.
2002-08-25 00:22:31 +00:00
Poul-Henning Kamp
7428de69d2 Implement list of EA return functionality.
Correctly delete EA's when the content length is set to zero.

Sponsored by:	DARPA & NAI Labs.
2002-08-20 11:34:58 +00:00
Poul-Henning Kamp
0176455bc8 First snapshot of UFS2 EA support.
Sponsored by: DARPA & NAI Labs.
2002-08-19 07:01:55 +00:00
Robert Watson
9ca435893b In order to better support flexible and extensible access control,
make a series of modifications to the credential arguments relating
to file read and write operations to cliarfy which credential is
used for what:

- Change fo_read() and fo_write() to accept "active_cred" instead of
  "cred", and change the semantics of consumers of fo_read() and
  fo_write() to pass the active credential of the thread requesting
  an operation rather than the cached file cred.  The cached file
  cred is still available in fo_read() and fo_write() consumers
  via fp->f_cred.  These changes largely in sys_generic.c.

For each implementation of fo_read() and fo_write(), update cred
usage to reflect this change and maintain current semantics:

- badfo_readwrite() unchanged
- kqueue_read/write() unchanged
  pipe_read/write() now authorize MAC using active_cred rather
  than td->td_ucred
- soo_read/write() unchanged
- vn_read/write() now authorize MAC using active_cred but
  VOP_READ/WRITE() with fp->f_cred

Modify vn_rdwr() to accept two credential arguments instead of a
single credential: active_cred and file_cred.  Use active_cred
for MAC authorization, and select a credential for use in
VOP_READ/WRITE() based on whether file_cred is NULL or not.  If
file_cred is provided, authorize the VOP using that cred,
otherwise the active credential, matching current semantics.

Modify current vn_rdwr() consumers to pass a file_cred if used
in the context of a struct file, and to always pass active_cred.
When vn_rdwr() is used without a file_cred, pass NOCRED.

These changes should maintain current semantics for read/write,
but avoid a redundant passing of fp->f_cred, as well as making
it more clear what the origin of each credential is in file
descriptor read/write operations.

Follow-up commits will make similar changes to other file descriptor
operations, and modify the MAC framework to pass both credentials
to MAC policy modules so they can implement either semantic for
revocation.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, NAI Labs
2002-08-15 20:55:08 +00:00
Poul-Henning Kamp
18280bc653 Expand the arguments to ffs_ext{read,write}() to their component
parts rather than use vop_{read,write}_args.  Access to these
functions will ultimately not be available through the
"vop_{read,write}+IO_EXT" API but this functionality is retained
for debugging purposes for now.

Sponsored by: DARPA & NAI Labs.
2002-08-13 11:33:01 +00:00
Poul-Henning Kamp
d6fe88e475 Unravel the UFS_EXTATTR incest between FFS and UFS: UFS_EXTATTR is an
UFS only thing, and FFS should in principle not know if it is enabled
or not.

This commit cleans ffs_vnops.c for such knowledge, but not ffs_vfsops.c

Sponsored by: DARPA and NAI Labs.
2002-08-13 10:33:57 +00:00
Poul-Henning Kamp
9bf1a75697 Introduce typedefs for the member functions of struct vfsops and employ
these in the main filesystems.  This does not change the resulting code
but makes the source a little bit more grepable.

Sponsored by:	DARPA and NAI Labs.
2002-08-13 10:05:50 +00:00
Robert Watson
c08b677fb5 Pass IO_NOMACCHECK to vn_rdwr() in the following checks to prevent
enforcement of MAC policy on the read or write operations:

- In ext2fs, don't enforce MAC on loop-back reads and writes supporting
  directory read operations in lookup(), directory modifications in
  rename(), directory write operations in mkdir(), symlink write
  operations in symlink().

- In the NFS client locking code, perform vn_rdwr() on the NFS locking
  socket without enforcing MAC, since the write is done on behalf of
  the kernel NFS implementation rather than the user process.

- In UFS, don't enforce MAC on loop-back reads and writes supporting
  directory read operations in lookup(), and symlink write operations
  in symlink().

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, NAI Labs
2002-08-12 16:43:04 +00:00
Poul-Henning Kamp
e179b40f14 Stop pretending that the FFS file ufs_readwrite.c is a UFS file.
Instead of #including it, pull it into ffs_vnops.c and name things
correctly.

Sponsored by:	DARPA & NAI Labs.
2002-08-12 10:32:56 +00:00
Poul-Henning Kamp
851da5d6cf Fix a comment. 2002-08-12 09:22:11 +00:00
Ian Dowse
98caa2e4e9 Don't call softdep_slowdown() if soft updates are not active on the
filesystem. This causes a panic for kernels compiled without
softupdates.

Reported by:	luigi
2002-08-05 17:59:20 +00:00
Jeff Roberson
e6e370a7fe - 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
Robert Watson
af05e056ec Introduce support for Mandatory Access Control and extensible
kernel access control.

Instrument UFS to support per-inode MAC labels.  In particular,
invoke MAC framework entry points for generically supporting the
backing of MAC labels into extended attributes.  This ends up
introducing new vnode operation vector entries point at the MAC
framework entry points, as well as some explicit entry point
invocations for file and directory creation events so that the
MAC framework can push labels to disk before the directory names
become persistent (this will work better once EAs in UFS2 are
hooked into soft updates).  The generic EA MAC entry points
support executing with the file system in either single label
or multilabel operation, and will fall back to the mount label
if multilabel is not specified at mount-time.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, NAI Labs
2002-07-31 16:05:30 +00:00
Poul-Henning Kamp
c3a0d1d4e1 I forgot this bit of uglyness in the fsck_ffs cleanup. 2002-07-31 07:01:18 +00:00
Poul-Henning Kamp
9fbc6a330d Fix braino in last commit. 2002-07-30 12:02:41 +00:00
Poul-Henning Kamp
17b1994bbe Move ffs_isfreeblock() to ffs_alloc.c and make it static.
Sponsored by: DARPA & NAI Labs.
2002-07-30 11:54:48 +00:00
Alan Cox
1e8fabc097 Lock page queue accesses by vm_page_free(). 2002-07-28 08:01:48 +00:00
Benno Rice
683eac8dbb Add a missing argument to the stub for softdep_setup_freeblocks.
Forgotten by:	mckusick
2002-07-20 04:07:15 +00:00
Peter Wemm
382f95d332 Fix a warning:
ffs_softdep.c:1630: warning: int format, different type arg (arg 2)
2002-07-20 01:09:35 +00:00
Kirk McKusick
7aca6291e3 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
Kirk McKusick
fb36a3d847 Change utimes to set the file creation time (for filesystems that
support creation times such as UFS2) to the value of the
modification time if the value of the modification time is older
than the current creation time. See utimes(2) for further details.

Sponsored by:	DARPA & NAI Labs.
2002-07-17 02:03:19 +00:00
Kirk McKusick
faab4e2722 Change the name of st_createtime to st_birthtime. This change is
made to reduce confusion between st_ctime and st_createtime.

Submitted by:	Eric Allman <eric@sendmail.org>
Sponsored by:	DARPA & NAI Labs.
2002-07-16 22:36:00 +00:00
Tom Rhodes
ae76f60046 Fix a type: s/your are/you are/ 2002-07-12 19:56:31 +00:00
Bruce Evans
2daf9dc825 Fixed some printf format errors (4 new ones reported by gcc and 5 nearby
old ones not reported by gcc).  This helps unbreak LINT.
2002-07-08 12:42:29 +00:00
Ian Dowse
6bd521df93 Use indirect function pointer hooks instead of #ifdef SOFTUPDATES
direct calls for the two places where the kernel calls into soft
updates code. Set up the hooks in softdep_initialize() and NULL
them out in softdep_uninitialize(). This change allows soft updates
to function correctly when ufs is loaded as a module.

Reviewed by:	mckusick
2002-07-01 17:59:40 +00:00
Ian Dowse
5346934fe7 Add the ffs bits necessary to support unloading of the ufs kernel
module. This adds an ffs_uninit() function that calls ufs_uninit()
and also calls a new softdep_uninitialize() function. Add a stub
for softdep_uninitialize() to cover the non-SOFTUPDATES case.

Reviewed by:	mckusick
2002-07-01 11:00:47 +00:00
Ian Dowse
3423b21c09 Remove the bogus SYSINIT from ufs_dirhash.c and instead add a call
to ufsdirhash_init() from ufs_init(). Add uninit() functions
corresponding the ufs, dirhash, quota and ihash init() functions.
2002-06-30 02:49:39 +00:00
Ian Dowse
8f42fb8fc9 Remove the kernel file-size limit for UFS2, so that only the limit
imposed by the filesystem structure itself remains. With 16k blocks,
the maximum file size is now just over 128TB.

For now, the UFS1 file size limit is left unchanged so as to remain
consistent with RELENG_4, but it too could be removed in the future.

Reviewed by:	mckusick
2002-06-26 18:34:51 +00:00
Kenneth D. Merry
98cb733c67 At long last, commit the zero copy sockets code.
MAKEDEV:	Add MAKEDEV glue for the ti(4) device nodes.

ti.4:		Update the ti(4) man page to include information on the
		TI_JUMBO_HDRSPLIT and TI_PRIVATE_JUMBOS kernel options,
		and also include information about the new character
		device interface and the associated ioctls.

man9/Makefile:	Add jumbo.9 and zero_copy.9 man pages and associated
		links.

jumbo.9:	New man page describing the jumbo buffer allocator
		interface and operation.

zero_copy.9:	New man page describing the general characteristics of
		the zero copy send and receive code, and what an
		application author should do to take advantage of the
		zero copy functionality.

NOTES:		Add entries for ZERO_COPY_SOCKETS, TI_PRIVATE_JUMBOS,
		TI_JUMBO_HDRSPLIT, MSIZE, and MCLSHIFT.

conf/files:	Add uipc_jumbo.c and uipc_cow.c.

conf/options:	Add the 5 options mentioned above.

kern_subr.c:	Receive side zero copy implementation.  This takes
		"disposable" pages attached to an mbuf, gives them to
		a user process, and then recycles the user's page.
		This is only active when ZERO_COPY_SOCKETS is turned on
		and the kern.ipc.zero_copy.receive sysctl variable is
		set to 1.

uipc_cow.c:	Send side zero copy functions.  Takes a page written
		by the user and maps it copy on write and assigns it
		kernel virtual address space.  Removes copy on write
		mapping once the buffer has been freed by the network
		stack.

uipc_jumbo.c:	Jumbo disposable page allocator code.  This allocates
		(optionally) disposable pages for network drivers that
		want to give the user the option of doing zero copy
		receive.

uipc_socket.c:	Add kern.ipc.zero_copy.{send,receive} sysctls that are
		enabled if ZERO_COPY_SOCKETS is turned on.

		Add zero copy send support to sosend() -- pages get
		mapped into the kernel instead of getting copied if
		they meet size and alignment restrictions.

uipc_syscalls.c:Un-staticize some of the sf* functions so that they
		can be used elsewhere.  (uipc_cow.c)

if_media.c:	In the SIOCGIFMEDIA ioctl in ifmedia_ioctl(), avoid
		calling malloc() with M_WAITOK.  Return an error if
		the M_NOWAIT malloc fails.

		The ti(4) driver and the wi(4) driver, at least, call
		this with a mutex held.  This causes witness warnings
		for 'ifconfig -a' with a wi(4) or ti(4) board in the
		system.  (I've only verified for ti(4)).

ip_output.c:	Fragment large datagrams so that each segment contains
		a multiple of PAGE_SIZE amount of data plus headers.
		This allows the receiver to potentially do page
		flipping on receives.

if_ti.c:	Add zero copy receive support to the ti(4) driver.  If
		TI_PRIVATE_JUMBOS is not defined, it now uses the
		jumbo(9) buffer allocator for jumbo receive buffers.

		Add a new character device interface for the ti(4)
		driver for the new debugging interface.  This allows
		(a patched version of) gdb to talk to the Tigon board
		and debug the firmware.  There are also a few additional
		debugging ioctls available through this interface.

		Add header splitting support to the ti(4) driver.

		Tweak some of the default interrupt coalescing
		parameters to more useful defaults.

		Add hooks for supporting transmit flow control, but
		leave it turned off with a comment describing why it
		is turned off.

if_tireg.h:	Change the firmware rev to 12.4.11, since we're really
		at 12.4.11 plus fixes from 12.4.13.

		Add defines needed for debugging.

		Remove the ti_stats structure, it is now defined in
		sys/tiio.h.

ti_fw.h:	12.4.11 firmware.

ti_fw2.h:	12.4.11 firmware, plus selected fixes from 12.4.13,
		and my header splitting patches.  Revision 12.4.13
		doesn't handle 10/100 negotiation properly.  (This
		firmware is the same as what was in the tree previously,
		with the addition of header splitting support.)

sys/jumbo.h:	Jumbo buffer allocator interface.

sys/mbuf.h:	Add a new external mbuf type, EXT_DISPOSABLE, to
		indicate that the payload buffer can be thrown away /
		flipped to a userland process.

socketvar.h:	Add prototype for socow_setup.

tiio.h:		ioctl interface to the character portion of the ti(4)
		driver, plus associated structure/type definitions.

uio.h:		Change prototype for uiomoveco() so that we'll know
		whether the source page is disposable.

ufs_readwrite.c:Update for new prototype of uiomoveco().

vm_fault.c:	In vm_fault(), check to see whether we need to do a page
		based copy on write fault.

vm_object.c:	Add a new function, vm_object_allocate_wait().  This
		does the same thing that vm_object allocate does, except
		that it gives the caller the opportunity to specify whether
		it should wait on the uma_zalloc() of the object structre.

		This allows vm objects to be allocated while holding a
		mutex.  (Without generating WITNESS warnings.)

		vm_object_allocate() is implemented as a call to
		vm_object_allocate_wait() with the malloc flag set to
		M_WAITOK.

vm_object.h:	Add prototype for vm_object_allocate_wait().

vm_page.c:	Add page-based copy on write setup, clear and fault
		routines.

vm_page.h:	Add page based COW function prototypes and variable in
		the vm_page structure.

Many thanks to Drew Gallatin, who wrote the zero copy send and receive
code, and to all the other folks who have tested and reviewed this code
over the years.
2002-06-26 03:37:47 +00:00
Kirk McKusick
a7d50c22a6 Force the quota update to be done when an inode is released in
ufs_inactive. This avoid a panic when checking a NULL credential
in suser_cred().
2002-06-25 01:02:28 +00:00
Jonathan Lemon
c86c4abf99 Prototype fixes (long newinum --> ino_t newinum). 2002-06-24 17:20:19 +00:00
Maxime Henrion
cfbf0a4678 Warning fixes for 64 bits platforms. This eliminates all the
warnings I have had in the FFS code on sparc64.

Reviewed by:	mckusick
2002-06-23 18:17:27 +00:00
Matthew Dillon
10cfbc1978 Rename the BALLOC flags from B_* to BA_* to avoid confusion with the
struct buf B_ flags.

Approved by:	mckusick
2002-06-23 06:12:22 +00:00
Kirk McKusick
5006e77609 This patch fixes a problem whereby filesystems that ran
out of inodes in a cylinder group would fail to check for
free inodes in other cylinder groups. This bug was introduced
in the UFS2 code merge two days ago.

An inode is allocated by calling ffs_valloc which calls
ffs_hashalloc to do the filesystem scan. Ffs_hashalloc
walks around the cylinder groups calling its passed allocator
(ffs_nodealloccg in this case) until the allocator returns a
non-zero result. The bug is that ffs_hashalloc expects the
passed allocator function to return a 64-bit ufs2_daddr_t.
When allocating inodes, it calls ffs_nodealloccg which was
returning a 32-bit ino_t. The ffs_hashalloc code checked
a 64-bit return value and usually found random non-zero bits in
the high 32-bits so decided that the allocation had succeeded
(in this case in the only cylinder group that it checked).
When the result was passed back to ffs_valloc it looked at
only the bottom 32-bits, saw zero and declared the system
out of inodes. But ffs_hashalloc had really only checked
one cylinder group.

The fix is to change ffs_nodealloccg to return 64-bit results.

Sponsored by:	DARPA & NAI Labs.
Submitted by:	Poul-Henning Kamp <phk@critter.freebsd.dk>
Reviewed by:	Maxime Henrion <mux@freebsd.org>
2002-06-22 21:24:58 +00:00
Kirk McKusick
1c85e6a35d 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
Matthew Dillon
a37313d234 In rev 1.72 a situation related to write/mmap was fixed which could result
in a user process gaining visibility into the 'old' contents of a filesystem
block.  There were two cases:  (1) when uiomove() fails (user process issues
illegal write), and (2) when uiomove() overlaps a mmap() of the same file at
the same offset (fault -> recursive buffer I/O reads contents of old block).

Unfortunately 1.72 also had the unintended effect of forcing the filesystem
to do a read-before-write in the case of a full-block-write (non append case),
e.g. 'dd if=/dev/zero of=test.dat bs=1m count=256 conv=notrunc'.  This
destroys performance.. not only is a read forced for every write, but
clustering breaks as well.

The solution is to clear the buffer manually in the full-block case rather
then asking BALLOC to do it (BALLOC issues the read-before-write).  In the
partial-block case we want BALLOC to do it because the read-before-write
is necessary.  This patch should greatly improve database and news-feed
server performance.

Found by: MKI <mki@mozone.net>
MFC after:	3 days
2002-06-19 09:39:41 +00:00
Semen Ustimenko
13866b3fd2 Fix a typo in my recently added comment: s/beleived/believed/
Submitted by:	keramida
2002-06-06 20:43:03 +00:00
Alfred Perlstein
ba5a4d6c02 Backout/modify previous revision:
"empty default cases shouldn't be removed, they should have a break;
  statement added to them."

Requested by: billf
2002-06-01 20:54:21 +00:00
Alfred Perlstein
37e1dd483d Silence warnings, remove some empty 'default' switch cases. 2002-06-01 20:40:42 +00:00
Semen Ustimenko
f576a00d1b Remove lock from ffs_vget introduced by v1.24. Instead of locking the
vnode creation globaly, we allow processes to create vnodes concurently.
In case of concurent creation of vnode for the one ino, we allow processes
to race and then check who wins.

Assuming that concurent creation of vnode for same ino is really rare case,
this is belived to be an improvement, as it just allows concurent creation
of vnodes.

Idea by:	bp
Reviewed by:	dillon
MFC after:	1 month
2002-05-30 22:04:17 +00:00