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  1. 07 11月, 2008 1 次提交
  3. 17 10月, 2008 1 次提交
  5. 18 10月, 2008 1 次提交
  7. 11 10月, 2008 1 次提交
  9. 30 9月, 2008 1 次提交
    • T
      Configure out file locking features · bfcd17a6
      由 Thomas Petazzoni 提交于 
      This patch adds the CONFIG_FILE_LOCKING option which allows to remove
support for advisory locks. With this patch enabled, the flock()
system call, the F_GETLK, F_SETLK and F_SETLKW operations of fcntl()
and NFS support are disabled. These features are not necessarly needed
on embedded systems. It allows to save ~11 Kb of kernel code and data:

   text          data     bss     dec     hex filename
1125436        118764  212992 1457192  163c28 vmlinux.old
1114299        118564  212992 1445855  160fdf vmlinux
 -11137    -200       0  -11337   -2C49 +/-

This patch has originally been written by Matt Mackall
<mpm@selenic.com>, and is part of the Linux Tiny project.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: NMatt Mackall <mpm@selenic.com>
Cc: matthew@wil.cx
Cc: linux-fsdevel@vger.kernel.org
Cc: mpm@selenic.com
Cc: akpm@linux-foundation.org
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
      bfcd17a6
  11. 27 7月, 2008 1 次提交
  13. 15 7月, 2008 1 次提交
  15. 03 7月, 2008 1 次提交
  17. 30 1月, 2008 1 次提交
  19. 17 10月, 2007 1 次提交
  21. 11 5月, 2007 4 次提交
    • D
      signal/timer/event: eventfd core · e1ad7468
      由 Davide Libenzi 提交于 
      This is a very simple and light file descriptor, that can be used as event
wait/dispatch by userspace (both wait and dispatch) and by the kernel
(dispatch only).  It can be used instead of pipe(2) in all cases where those
would simply be used to signal events.  Their kernel overhead is much lower
than pipes, and they do not consume two fds.  When used in the kernel, it can
offer an fd-bridge to enable, for example, functionalities like KAIO or
syslets/threadlets to signal to an fd the completion of certain operations.
But more in general, an eventfd can be used by the kernel to signal readiness,
in a POSIX poll/select way, of interfaces that would otherwise be incompatible
with it.  The API is:

int eventfd(unsigned int count);

The eventfd API accepts an initial "count" parameter, and returns an eventfd
fd.  It supports poll(2) (POLLIN, POLLOUT, POLLERR), read(2) and write(2).

The POLLIN flag is raised when the internal counter is greater than zero.

The POLLOUT flag is raised when at least a value of "1" can be written to the
internal counter.

The POLLERR flag is raised when an overflow in the counter value is detected.

The write(2) operation can never overflow the counter, since it blocks (unless
O_NONBLOCK is set, in which case -EAGAIN is returned).

But the eventfd_signal() function can do it, since it's supposed to not sleep
during its operation.

The read(2) function reads the __u64 counter value, and reset the internal
value to zero.  If the value read is equal to (__u64) -1, an overflow happened
on the internal counter (due to 2^64 eventfd_signal() posts that has never
been retired - unlickely, but possible).

The write(2) call writes an __u64 count value, and adds it to the current
counter.  The eventfd fd supports O_NONBLOCK also.

On the kernel side, we have:

struct file *eventfd_fget(int fd);
int eventfd_signal(struct file *file, unsigned int n);

The eventfd_fget() should be called to get a struct file* from an eventfd fd
(this is an fget() + check of f_op being an eventfd fops pointer).

The kernel can then call eventfd_signal() every time it wants to post an event
to userspace.  The eventfd_signal() function can be called from any context.
An eventfd() simple test and bench is available here:

http://www.xmailserver.org/eventfd-bench.c

This is the eventfd-based version of pipetest-4 (pipe(2) based):

http://www.xmailserver.org/pipetest-4.c

Not that performance matters much in the eventfd case, but eventfd-bench
shows almost as double as performance than pipetest-4.

[akpm@linux-foundation.org: fix i386 build]
[akpm@linux-foundation.org: add sys_eventfd to sys_ni.c]
Signed-off-by: NDavide Libenzi <davidel@xmailserver.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      e1ad7468
    • D
      signal/timer/event: timerfd core · b215e283
      由 Davide Libenzi 提交于 
      This patch introduces a new system call for timers events delivered though
file descriptors.  This allows timer event to be used with standard POSIX
poll(2), select(2) and read(2).  As a consequence of supporting the Linux
f_op->poll subsystem, they can be used with epoll(2) too.

The system call is defined as:

int timerfd(int ufd, int clockid, int flags, const struct itimerspec *utmr);

The "ufd" parameter allows for re-use (re-programming) of an existing timerfd
w/out going through the close/open cycle (same as signalfd).  If "ufd" is -1,
s new file descriptor will be created, otherwise the existing "ufd" will be
re-programmed.

The "clockid" parameter is either CLOCK_MONOTONIC or CLOCK_REALTIME.  The time
specified in the "utmr->it_value" parameter is the expiry time for the timer.

If the TFD_TIMER_ABSTIME flag is set in "flags", this is an absolute time,
otherwise it's a relative time.

If the time specified in the "utmr->it_interval" is not zero (.tv_sec == 0,
tv_nsec == 0), this is the period at which the following ticks should be
generated.

The "utmr->it_interval" should be set to zero if only one tick is requested.
Setting the "utmr->it_value" to zero will disable the timer, or will create a
timerfd without the timer enabled.

The function returns the new (or same, in case "ufd" is a valid timerfd
descriptor) file, or -1 in case of error.

As stated before, the timerfd file descriptor supports poll(2), select(2) and
epoll(2).  When a timer event happened on the timerfd, a POLLIN mask will be
returned.

The read(2) call can be used, and it will return a u32 variable holding the
number of "ticks" that happened on the interface since the last call to
read(2).  The read(2) call supportes the O_NONBLOCK flag too, and EAGAIN will
be returned if no ticks happened.

A quick test program, shows timerfd working correctly on my amd64 box:

http://www.xmailserver.org/timerfd-test.c

[akpm@linux-foundation.org: add sys_timerfd to sys_ni.c]
Signed-off-by: NDavide Libenzi <davidel@xmailserver.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      b215e283
    • D
      signal/timer/event: signalfd core · fba2afaa
      由 Davide Libenzi 提交于 
      This patch series implements the new signalfd() system call.

I took part of the original Linus code (and you know how badly it can be
broken :), and I added even more breakage ;) Signals are fetched from the same
signal queue used by the process, so signalfd will compete with standard
kernel delivery in dequeue_signal().  If you want to reliably fetch signals on
the signalfd file, you need to block them with sigprocmask(SIG_BLOCK).  This
seems to be working fine on my Dual Opteron machine.  I made a quick test
program for it:

http://www.xmailserver.org/signafd-test.c

The signalfd() system call implements signal delivery into a file descriptor
receiver.  The signalfd file descriptor if created with the following API:

int signalfd(int ufd, const sigset_t *mask, size_t masksize);

The "ufd" parameter allows to change an existing signalfd sigmask, w/out going
to close/create cycle (Linus idea).  Use "ufd" == -1 if you want a brand new
signalfd file.

The "mask" allows to specify the signal mask of signals that we are interested
in.  The "masksize" parameter is the size of "mask".

The signalfd fd supports the poll(2) and read(2) system calls.  The poll(2)
will return POLLIN when signals are available to be dequeued.  As a direct
consequence of supporting the Linux poll subsystem, the signalfd fd can use
used together with epoll(2) too.

The read(2) system call will return a "struct signalfd_siginfo" structure in
the userspace supplied buffer.  The return value is the number of bytes copied
in the supplied buffer, or -1 in case of error.  The read(2) call can also
return 0, in case the sighand structure to which the signalfd was attached,
has been orphaned.  The O_NONBLOCK flag is also supported, and read(2) will
return -EAGAIN in case no signal is available.

If the size of the buffer passed to read(2) is lower than sizeof(struct
signalfd_siginfo), -EINVAL is returned.  A read from the signalfd can also
return -ERESTARTSYS in case a signal hits the process.  The format of the
struct signalfd_siginfo is, and the valid fields depends of the (->code &
__SI_MASK) value, in the same way a struct siginfo would:

struct signalfd_siginfo {
	__u32 signo;	/* si_signo */
	__s32 err;	/* si_errno */
	__s32 code;	/* si_code */
	__u32 pid;	/* si_pid */
	__u32 uid;	/* si_uid */
	__s32 fd;	/* si_fd */
	__u32 tid;	/* si_fd */
	__u32 band;	/* si_band */
	__u32 overrun;	/* si_overrun */
	__u32 trapno;	/* si_trapno */
	__s32 status;	/* si_status */
	__s32 svint;	/* si_int */
	__u64 svptr;	/* si_ptr */
	__u64 utime;	/* si_utime */
	__u64 stime;	/* si_stime */
	__u64 addr;	/* si_addr */
};

[akpm@linux-foundation.org: fix signalfd_copyinfo() on i386]
Signed-off-by: NDavide Libenzi <davidel@xmailserver.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      fba2afaa
    • D
      signal/timer/event fds: anonymous inode source · 5dc8bf81
      由 Davide Libenzi 提交于 
      This patch add an anonymous inode source, to be used for files that need
and inode only in order to create a file*. We do not care of having an
inode for each file, and we do not even care of having different names in
the associated dentries (dentry names will be same for classes of file*).
This allow code reuse, and will be used by epoll, signalfd and timerfd
(and whatever else there'll be).
Signed-off-by: NDavide Libenzi <davidel@xmailserver.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      5dc8bf81
  23. 18 2月, 2007 1 次提交
  25. 09 12月, 2006 1 次提交
  27. 12 10月, 2006 2 次提交
  29. 04 10月, 2006 1 次提交
  31. 01 10月, 2006 2 次提交
    • A
      [PATCH] Create fs/utimes.c · 82b0547c
      由 Alexey Dobriyan 提交于 
      * fs/open.c is getting bit crowdy
* preparation to lutimes(2)
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      82b0547c
    • D
      [PATCH] BLOCK: Make it possible to disable the block layer [try #6] · 9361401e
      由 David Howells 提交于 
      Make it possible to disable the block layer.  Not all embedded devices require
it, some can make do with just JFFS2, NFS, ramfs, etc - none of which require
the block layer to be present.

This patch does the following:

 (*) Introduces CONFIG_BLOCK to disable the block layer, buffering and blockdev
     support.

 (*) Adds dependencies on CONFIG_BLOCK to any configuration item that controls
     an item that uses the block layer.  This includes:

     (*) Block I/O tracing.

     (*) Disk partition code.

     (*) All filesystems that are block based, eg: Ext3, ReiserFS, ISOFS.

     (*) The SCSI layer.  As far as I can tell, even SCSI chardevs use the
     	 block layer to do scheduling.  Some drivers that use SCSI facilities -
     	 such as USB storage - end up disabled indirectly from this.

     (*) Various block-based device drivers, such as IDE and the old CDROM
     	 drivers.

     (*) MTD blockdev handling and FTL.

     (*) JFFS - which uses set_bdev_super(), something it could avoid doing by
     	 taking a leaf out of JFFS2's book.

 (*) Makes most of the contents of linux/blkdev.h, linux/buffer_head.h and
     linux/elevator.h contingent on CONFIG_BLOCK being set.  sector_div() is,
     however, still used in places, and so is still available.

 (*) Also made contingent are the contents of linux/mpage.h, linux/genhd.h and
     parts of linux/fs.h.

 (*) Makes a number of files in fs/ contingent on CONFIG_BLOCK.

 (*) Makes mm/bounce.c (bounce buffering) contingent on CONFIG_BLOCK.

 (*) set_page_dirty() doesn't call __set_page_dirty_buffers() if CONFIG_BLOCK
     is not enabled.

 (*) fs/no-block.c is created to hold out-of-line stubs and things that are
     required when CONFIG_BLOCK is not set:

     (*) Default blockdev file operations (to give error ENODEV on opening).

 (*) Makes some /proc changes:

     (*) /proc/devices does not list any blockdevs.

     (*) /proc/diskstats and /proc/partitions are contingent on CONFIG_BLOCK.

 (*) Makes some compat ioctl handling contingent on CONFIG_BLOCK.

 (*) If CONFIG_BLOCK is not defined, makes sys_quotactl() return -ENODEV if
     given command other than Q_SYNC or if a special device is specified.

 (*) In init/do_mounts.c, no reference is made to the blockdev routines if
     CONFIG_BLOCK is not defined.  This does not prohibit NFS roots or JFFS2.

 (*) The bdflush, ioprio_set and ioprio_get syscalls can now be absent (return
     error ENOSYS by way of cond_syscall if so).

 (*) The seclvl_bd_claim() and seclvl_bd_release() security calls do nothing if
     CONFIG_BLOCK is not set, since they can't then happen.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>
      9361401e
  33. 30 9月, 2006 1 次提交
    • A
      [PATCH] Generic infrastructure for acls · f0c8bd16
      由 Andreas Gruenbacher 提交于 
      The patches solve the following problem: We want to grant access to devices
based on who is logged in from where, etc.  This includes switching back and
forth between multiple user sessions, etc.

Using ACLs to define device access for logged-in users gives us all the
flexibility we need in order to fully solve the problem.

Device special files nowadays usually live on tmpfs, hence tmpfs ACLs.

Different distros have come up with solutions that solve the problem to
different degrees: SUSE uses a resource manager which tracks login sessions
and sets ACLs on device inodes as appropriate.  RedHat uses pam_console, which
changes the primary file ownership to the logged-in user.  Others use a set of
groups that users must be in in order to be granted the appropriate accesses.

The freedesktop.org project plans to implement a combination of a
console-tracker and a HAL-device-list based solution to grant access to
devices to users, and more distros will likely follow this approach.

These patches have first been posted here on 2 February 2005, and again
on 8 January 2006. We have been shipping them in SLES9 and SLES10 with
no problems reported.  The previous submission is archived here:

   http://lkml.org/lkml/2006/1/8/229
   http://lkml.org/lkml/2006/1/8/230
   http://lkml.org/lkml/2006/1/8/231

This patch:

Add some infrastructure for access control lists on in-memory
filesystems such as tmpfs.
Signed-off-by: NAndreas Gruenbacher <agruen@suse.de>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      f0c8bd16
  35. 27 6月, 2006 1 次提交
  37. 20 6月, 2006 1 次提交
  39. 18 5月, 2006 1 次提交
  41. 01 4月, 2006 1 次提交
    • A
      [PATCH] sys_sync_file_range() · f79e2abb
      由 Andrew Morton 提交于 
      Remove the recently-added LINUX_FADV_ASYNC_WRITE and LINUX_FADV_WRITE_WAIT
fadvise() additions, do it in a new sys_sync_file_range() syscall instead.
Reasons:

- It's more flexible.  Things which would require two or three syscalls with
  fadvise() can be done in a single syscall.

- Using fadvise() in this manner is something not covered by POSIX.

The patch wires up the syscall for x86.

The sycall is implemented in the new fs/sync.c.  The intention is that we can
move sys_fsync(), sys_fdatasync() and perhaps sys_sync() into there later.

Documentation for the syscall is in fs/sync.c.

A test app (sync_file_range.c) is in
http://www.zip.com.au/~akpm/linux/patches/stuff/ext3-tools.tar.gz.

The available-to-GPL-modules do_sync_file_range() is for knfsd: "A COMMIT can
say NFS_DATA_SYNC or NFS_FILE_SYNC.  I can skip the ->fsync call for
NFS_DATA_SYNC which is hopefully the more common."

Note: the `async' writeout mode SYNC_FILE_RANGE_WRITE will turn synchronous if
the queue is congested.  This is trivial to fix: add a new flag bit, set
wbc->nonblocking.  But I'm not sure that we want to expose implementation
details down to that level.

Note: it's notable that we can sync an fd which wasn't opened for writing.
Same with fsync() and fdatasync()).

Note: the code takes some care to handle attempts to sync file contents
outside the 16TB offset on 32-bit machines.  It makes such attempts appear to
succeed, for best 32-bit/64-bit compatibility.  Perhaps it should make such
requests fail...

Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Michael Kerrisk <mtk-manpages@gmx.net>
Cc: Ulrich Drepper <drepper@redhat.com>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      f79e2abb
  43. 31 3月, 2006 1 次提交
    • J
      [PATCH] Introduce sys_splice() system call · 5274f052
      由 Jens Axboe 提交于 
      This adds support for the sys_splice system call. Using a pipe as a
transport, it can connect to files or sockets (latter as output only).

From the splice.c comments:

   "splice": joining two ropes together by interweaving their strands.

   This is the "extended pipe" functionality, where a pipe is used as
   an arbitrary in-memory buffer. Think of a pipe as a small kernel
   buffer that you can use to transfer data from one end to the other.

   The traditional unix read/write is extended with a "splice()" operation
   that transfers data buffers to or from a pipe buffer.

   Named by Larry McVoy, original implementation from Linus, extended by
   Jens to support splicing to files and fixing the initial implementation
   bugs.
Signed-off-by: NJens Axboe <axboe@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      5274f052
  45. 24 3月, 2006 1 次提交
  47. 18 1月, 2006 1 次提交
  49. 17 1月, 2006 1 次提交
  51. 11 1月, 2006 1 次提交
    • C
      [PATCH] sanitize building of fs/compat_ioctl.c · e6a6d2ef
      由 Christoph Hellwig 提交于 
      Now that all these entries in the arch ioctl32.c files are gone [1], we can
build fs/compat_ioctl.c as a normal object and kill tons of cruft.  We need a
special do_ioctl32_pointer handler for s390 so the compat_ptr call is done.
This is not needed but harmless on all other architectures.  Also remove some
superflous includes in fs/compat_ioctl.c

Tested on ppc64.

[1] parisc still had it's PPP handler left, which is not fully correct
    for ppp and besides that ppp uses the generic SIOCPRIV ioctl so it'd
    kick in for all netdevice users.  We can introduce a proper handler
    in one of the next patch series by adding a compat_ioctl method to
    struct net_device but for now let's just kill it - parisc doesn't
    compile in mainline anyway and I don't want this to block this
    patchset.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Cc: Matthew Wilcox <willy@debian.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      e6a6d2ef
  53. 09 1月, 2006 1 次提交
    • A
      [PATCH] drop-pagecache · 9d0243bc
      由 Andrew Morton 提交于 
      Add /proc/sys/vm/drop_caches.  When written to, this will cause the kernel to
discard as much pagecache and/or reclaimable slab objects as it can.  THis
operation requires root permissions.

It won't drop dirty data, so the user should run `sync' first.

Caveats:

a) Holds inode_lock for exorbitant amounts of time.

b) Needs to be taught about NUMA nodes: propagate these all the way through
   so the discarding can be controlled on a per-node basis.

This is a debugging feature: useful for getting consistent results between
filesystem benchmarks.  We could possibly put it under a config option, but
it's less than 300 bytes.
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      9d0243bc
  55. 04 1月, 2006 2 次提交
  57. 08 11月, 2005 1 次提交
  59. 10 9月, 2005 2 次提交
    • M
      [PATCH] FUSE - MAINTAINERS, Kconfig and Makefile changes · 04578f17
      由 Miklos Szeredi 提交于 
      This patch adds FUSE filesystem to MAINTAINERS, fs/Kconfig and
fs/Makefile.
Signed-off-by: NMiklos Szeredi <miklos@szeredi.hu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      04578f17
    • E
      [PATCH] v9fs: Documentation, Makefiles, Configuration · 93fa58cb
      由 Eric Van Hensbergen 提交于 
      OVERVIEW

V9FS is a distributed file system for Linux which provides an
implementation of the Plan 9 resource sharing protocol 9P.  It can be
used to share all sorts of resources: static files, synthetic file servers
(such as /proc or /sys), devices, and application file servers (such as
FUSE).

BACKGROUND

Plan 9 (http://plan9.bell-labs.com/plan9) is a research operating
system and associated applications suite developed by the Computing
Science Research Center of AT&T Bell Laboratories (now a part of
Lucent Technologies), the same group that developed UNIX , C, and C++.
Plan 9 was initially released in 1993 to universities, and then made
generally available in 1995. Its core operating systems code laid the
foundation for the Inferno Operating System released as a product by
Lucent Bell-Labs in 1997. The Inferno venture was the only commercial
embodiment of Plan 9 and is currently maintained as a product by Vita
Nuova (http://www.vitanuova.com). After updated releases in 2000 and
2002, Plan 9 was open-sourced under the OSI approved Lucent Public
License in 2003.

The Plan 9 project was started by Ken Thompson and Rob Pike in 1985.
Their intent was to explore potential solutions to some of the
shortcomings of UNIX in the face of the widespread use of high-speed
networks to connect machines. In UNIX, networking was an afterthought
and UNIX clusters became little more than a network of stand-alone
systems. Plan 9 was designed from first principles as a seamless
distributed system with integrated secure network resource sharing.
Applications and services were architected in such a way as to allow
for implicit distribution across a cluster of systems. Configuring an
environment to use remote application components or services in place
of their local equivalent could be achieved with a few simple command
line instructions. For the most part, application implementations
operated independent of the location of their actual resources.

Commercial operating systems haven't changed much in the 20 years
since Plan 9 was conceived. Network and distributed systems support is
provided by a patchwork of middle-ware, with an endless number of
packages supplying pieces of the puzzle. Matters are complicated by
the use of different complicated protocols for individual services,
and separate implementations for kernel and application resources.
The V9FS project (http://v9fs.sourceforge.net) is an attempt to bring
Plan 9's unified approach to resource sharing to Linux and other
operating systems via support for the 9P2000 resource sharing
protocol.

V9FS HISTORY

V9FS was originally developed by Ron Minnich and Maya Gokhale at Los
Alamos National Labs (LANL) in 1997.  In November of 2001, Greg Watson
setup a SourceForge project as a public repository for the code which
supported the Linux 2.4 kernel.

About a year ago, I picked up the initial attempt Ron Minnich had
made to provide 2.6 support and got the code integrated into a 2.6.5
kernel.   I then went through a line-for-line re-write attempting to
clean-up the code while more closely following the Linux Kernel style
guidelines.  I co-authored a paper with Ron Minnich on the V9FS Linux
support including performance comparisons to NFSv3 using Bonnie and
PostMark - this paper appeared at the USENIX/FREENIX 2005
conference in April 2005:
( http://www.usenix.org/events/usenix05/tech/freenix/hensbergen.html ).

CALL FOR PARTICIPATION/REQUEST FOR COMMENTS

Our 2.6 kernel support is stabilizing and we'd like to begin pursuing
its integration into the official kernel tree.  We would appreciate any
review, comments, critiques, and additions from this community and are
actively seeking people to join our project and help us produce
something that would be acceptable and useful to the Linux community.

STATUS

The code is reasonably stable, although there are no doubt corner cases
our regression tests haven't discovered yet.  It is in regular use by several
of the developers and has been tested on x86 and PowerPC
(32-bit and 64-bit) in both small and large (LANL cluster) deployments.
Our current regression tests include fsx, bonnie, and postmark.

It was our intention to keep things as simple as possible for this
release -- trying to focus on correctness within the core of the
protocol support versus a rich set of features.  For example: a more
complete security model and cache layer are in the road map, but
excluded from this release.   Additionally, we have removed support for
mmap operations at Al Viro's request.

PERFORMANCE

Detailed performance numbers and analysis are included in the FREENIX
paper, but we show comparable performance to NFSv3 for large file
operations based on the Bonnie benchmark, and superior performance for
many small file operations based on the PostMark benchmark.   Somewhat
preliminary graphs (from the FREENIX paper) are available
(http://v9fs.sourceforge.net/perf/index.html).

RESOURCES

The source code is available in a few different forms:

tarballs: http://v9fs.sf.net
CVSweb: http://cvs.sourceforge.net/viewcvs.py/v9fs/linux-9p/
CVS: :pserver:anonymous@cvs.sourceforge.net:/cvsroot/v9fs/linux-9p
Git: rsync://v9fs.graverobber.org/v9fs (webgit: http://v9fs.graverobber.org)
9P: tcp!v9fs.graverobber.org!6564

The user-level server is available from either the Plan 9 distribution
or from http://v9fs.sf.net
Other support applications are still being developed, but preliminary
version can be downloaded from sourceforge.

Documentation on the protocol has historically been the Plan 9 Man
pages (http://plan9.bell-labs.com/sys/man/5/INDEX.html), but there is
an effort under way to write a more complete Internet-Draft style
specification (http://v9fs.sf.net/rfc).

There are a couple of mailing lists supporting v9fs, but the most used
is v9fs-developer@lists.sourceforge.net -- please direct/cc your
comments there so the other v9fs contibutors can participate in the
conversation.  There is also an IRC channel: irc://freenode.net/#v9fs

This part of the patch contains Documentation, Makefiles, and configuration
file changes.
Signed-off-by: NEric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      93fa58cb
  61. 08 9月, 2005 1 次提交
    • T
      [PATCH] relayfs · e82894f8
      由 Tom Zanussi 提交于 
      Here's the latest version of relayfs, against linux-2.6.11-mm2.  I'm hoping
you'll consider putting this version back into your tree - the previous
rounds of comment seem to have shaken out all the API issues and the number
of comments on the code itself have also steadily dwindled.

This patch is essentially the same as the relayfs redux part 5 patch, with
some minor changes based on reviewer comments.  Thanks again to Pekka
Enberg for those.  The patch size without documentation is now a little
smaller at just over 40k.  Here's a detailed list of the changes:

- removed the attribute_flags in relay open and changed it to a
  boolean specifying either overwrite or no-overwrite mode, and removed
  everything referencing the attribute flags.
- added a check for NULL names in relayfs_create_entry()
- got rid of the unnecessary multiple labels in relay_create_buf()
- some minor simplification of relay_alloc_buf() which got rid of a
  couple params
- updated the Documentation

In addition, this version (through code contained in the relay-apps tarball
linked to below, not as part of the relayfs patch) tries to make it as easy
as possible to create the cooperating kernel/user pieces of a typical and
common type of logging application, one where kernel logging is kicked off
when a user space data collection app starts and stops when the collection
app exits, with the data being automatically logged to disk in between.  To
create this type of application, you basically just include a header file
(relay-app.h, included in the relay-apps tarball) in your kernel module,
define a couple of callbacks and call an initialization function, and on
the user side call a single function that sets up and continuously monitors
the buffers, and writes data to files as it becomes available.  Channels
are created when the collection app is started and destroyed when it exits,
not when the kernel module is inserted, so different channel buffer sizes
can be specified for each separate run via command-line options.  See the
README in the relay-apps tarball for details.

Also included in the relay-apps tarball are a couple examples
demonstrating how you can use this to create quick and dirty kernel
logging/debugging applications.  They are:

- tprintk, short for 'tee printk', which temporarily puts a kprobe on
  printk() and writes a duplicate stream of printk output to a relayfs
  channel.  This could be used anywhere there's printk() debugging code
  in the kernel which you'd like to exercise, but would rather not have
  your system logs cluttered with debugging junk.  You'd probably want
  to kill klogd while you do this, otherwise there wouldn't be much
  point (since putting a kprobe on printk() doesn't change the output
  of printk()).  I've used this method to temporarily divert the packet
  logging output of the iptables LOG target from the system logs to
  relayfs files instead, for instance.

- klog, which just provides a printk-like formatted logging function
  on top of relayfs.  Again, you can use this to keep stuff out of your
  system logs if used in place of printk.

The example applications can be found here:

http://prdownloads.sourceforge.net/dprobes/relay-apps.tar.gz?download

From: Christoph Hellwig <hch@lst.de>

  avoid lookup_hash usage in relayfs
Signed-off-by: NTom Zanussi <zanussi@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      e82894f8
  63. 13 7月, 2005 1 次提交
    • R
      [PATCH] inotify · 0eeca283
      由 Robert Love 提交于 
      inotify is intended to correct the deficiencies of dnotify, particularly
its inability to scale and its terrible user interface:

        * dnotify requires the opening of one fd per each directory
          that you intend to watch. This quickly results in too many
          open files and pins removable media, preventing unmount.
        * dnotify is directory-based. You only learn about changes to
          directories. Sure, a change to a file in a directory affects
          the directory, but you are then forced to keep a cache of
          stat structures.
        * dnotify's interface to user-space is awful.  Signals?

inotify provides a more usable, simple, powerful solution to file change
notification:

        * inotify's interface is a system call that returns a fd, not SIGIO.
	  You get a single fd, which is select()-able.
        * inotify has an event that says "the filesystem that the item
          you were watching is on was unmounted."
        * inotify can watch directories or files.

Inotify is currently used by Beagle (a desktop search infrastructure),
Gamin (a FAM replacement), and other projects.

See Documentation/filesystems/inotify.txt.
Signed-off-by: NRobert Love <rml@novell.com>
Cc: John McCutchan <ttb@tentacle.dhs.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      0eeca283
  65. 28 6月, 2005 1 次提交
    • J
      [PATCH] Update cfq io scheduler to time sliced design · 22e2c507
      由 Jens Axboe 提交于 
      This updates the CFQ io scheduler to the new time sliced design (cfq
v3).  It provides full process fairness, while giving excellent
aggregate system throughput even for many competing processes.  It
supports io priorities, either inherited from the cpu nice value or set
directly with the ioprio_get/set syscalls.  The latter closely mimic
set/getpriority.

This import is based on my latest from -mm.
Signed-off-by: NJens Axboe <axboe@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      22e2c507