Nir Tzachar <tzachar@cs.bgu.ac.il> points out that if an ELF file specifies a
zero-length bss at a whacky address, we cannot load that binary because
padzero() tries to zero out the end of the page at the whacky address, and
that may not be writeable.
See also http://bugzilla.kernel.org/show_bug.cgi?id=5411
So teach load_elf_binary() to skip the bss settng altogether if the elf file
has a zero-length bss segment.
Cc: Roland McGrath <roland@redhat.com>
Cc: Daniel Jacobowitz <dan@debian.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Here is a compatibility fix between Linux and Solaris when used with VxFS
filesystems: Solaris usually accepts acl entries in any order, but with
VxFS it replies with NFSERR_INVAL when it sees a four-entry acl that is not
in canonical form. It may also fail with other non-canonical acls -- I
can't tell, because that case never triggers: We only send non-canonical
acls when we fake up an ACL_MASK entry.
Instead of adding fake ACL_MASK entries at the end, inserting them in the
correct position makes Solaris+VxFS happy. The Linux client and server
sides don't care about entry order. The three-entry-acl special case in
which we need a fake ACL_MASK entry was handled in xdr_nfsace_encode. The
patch moves this into nfsacl_encode.
Signed-off-by: Andreas Gruenbacher <agruen@suse.de>
Acked-by: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
v9fs_file_read and v9fs_file_write use kmalloc to allocate buffers as big
as the data buffer received as parameter. kmalloc cannot be used to
allocate buffers bigger than 128K, so reading/writing data in chunks bigger
than 128k fails.
This patch reorganizes v9fs_file_read and v9fs_file_write to allocate only
buffers as big as the maximum data that can be sent in one 9P message.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The third param in this call to vmap shouldn't be GFP_KERNEL, which
makes no sense, but rather VM_MAP. Thanks to Al Viro for spotting
this.
Signed-off-by: Tom Zanussi <zanussi@us.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
- added typedef unsigned int __nocast gfp_t;
- replaced __nocast uses for gfp flags with gfp_t - it gives exactly
the same warnings as far as sparse is concerned, doesn't change
generated code (from gcc point of view we replaced unsigned int with
typedef) and documents what's going on far better.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The nameidata "last.name" is always allocated with "__getname()", and
should always be free'd with "__putname()".
Using "putname()" without the underscores will leak memory, because the
allocation will have been hidden from the AUDITSYSCALL code.
Arguably the real bug is that the AUDITSYSCALL code is really broken,
but in the meantime this fixes the problem people see.
Reported by Robert Derr, patch by Rick Lindsley.
Acked-by: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
bfs_fill_super() walks the inode table to get the bitmap of free inodes
and collect stats. It has no business using iget() for that - it's a
lot of extra work, extra icache pollution and more complex code.
Switched to walking the damn thing directly.
Note: that also allows to kill ->i_dsk_ino in there - separate patch if
Tigran can confirm that this field can be zero only for deleted inodes
(i.e. something that could only be found during that scan and not by
normal lookups).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch fixes up a few problems with jfs's reserved inodes.
1. There is no need for the jfs code setting the I_DIRTY bits in i_state.
I am ashamed that the code ever did this, and surprised it hasn't been
noticed until now.
2. Make sure special inodes are on an inode hash list. If the inodes are
unhashed, __mark_inode_dirty will fail to put the inode on the
superblock's dirty list, and the data will not be flushed under memory
pressure.
3. Force writing journal data to disk when metapage_writepage is unable to
write a metadata page due to pending journal I/O.
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Check O_DIRECT and return -EINVAL error in open. dentry_open() also checks
this but only after the open method is called. This patch optimizes away
the unnecessary upcalls in this case.
It could be a correctness issue too: if filesystem has open() with side
effect, then it should fail before doing the open, not after.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Calling truncate() on hostfs spits a kernel warning "Something isn't
implemented here", but it still works fine.
Indeed, hostfs i_op->truncate doesn't do anything. But hostfs_setattr() ->
set_attr() correctly detects ATTR_SIZE and calls truncate() on the host. So
we should be safe (using ftruncate() may be better, in case the file is
unlinked on the host, but we aren't sure to have the file open for writing,
and reopening it would cause the same races; plus nobody should expect UML to
be so careful).
So, the warning is wrong, because the current implementation is working. Al,
am I correct, and can the warning be therefore dropped?
CC: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Recently aio_p{read,write} changed to perform retries internally rather
than returning -EIOCBRETRY. This inadvertantly resulted in always calling
aio_{read,write} with ki_left at 0 which would in turn immediately return
0. Harmless, but we can avoid this call by checking in the caller.
Signed-off-by: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Benjamin LaHaise <bcrl@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Only one of the run or kick path is supposed to put an iocb on the run
list. If both of them do it than one of them can end up referencing a
freed iocb. The kick path could delete the task_list item from the wait
queue before getting the ctx_lock and putting the iocb on the run list.
The run path was testing the task_list item outside the lock so that it
could catch ki_retry methods that return -EIOCBRETRY *without* putting the
iocb on a wait queue and promising to call kick_iocb. This unlocked check
could then race with the kick path to cause both to try and put the iocb on
the run list.
The patch stops the run path from testing task_list by requring that any
ki_retry that returns -EIOCBRETRY *must* guarantee that kick_iocb() will be
called in the future. aio_p{read,write}, the only in-tree -EIOCBRETRY
users, are updated.
Signed-off-by: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Benjamin LaHaise <bcrl@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Only one of the run or kick path is supposed to put an iocb on the run
list. If both of them do it than one of them can end up referencing a
freed iocb. The kick patch could set the Kicked bit before acquiring the
ctx_lock and putting the iocb on the run list. The run path, while holding
the ctx_lock, could see this partial kick and mistake it for a kick that
was deferred while it was doing work with the run_list NULLed out. It
would then race with the kick thread to add the iocb to the run list.
This patch moves the kick setting under the ctx_lock so that only one of
the kick or run path queues the iocb on the run list, as intended.
Signed-off-by: Zach Brown <zach.brown@oracle.com>
Signed-off-by: Benjamin LaHaise <bcrl@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
it seems that readv(2)/writev(2) syscalls do not call
file_permission callback. Looks like this is overlook.
I have filled the issue into redhat bugzilla as
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=169433
and got the recommendation to post this on lsm mailing list.
The following trivial patch solves the problem.
Signed-off-by: Kostik Belousov <kostikbel@gmail.com>
Signed-off-by: Chris Wright <chrisw@osdl.org>
Fid management cleanup. The patch attempts to fix the races in dentry's
fid management.
Dentries don't keep the opened fids anymore, they are moved to the file
structs. Ideally there should be no more than one fid with fidcreate equal
to zero in the dentry's list of fids.
v9fs_fid_create initializes the important fields (fid, fidcreated) before
v9fs_fid is added to the list. v9fs_fid_lookup returns only fids that are
not created by v9fs_create. v9fs_fid_get_created returns the fid created
by the same process by v9fs_create (if any) and removes it from dentry's
list
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix failure paths in ext3_new_inode() and clean up duplicated code: -
DQUOT_DROP() was not being called if ext3_init_security() failed.
Signed-off-by: Chris Sykes <chris@sigsegv.plus.com>
Cc: Stephen Smalley <sds@epoch.ncsc.mil>
Cc: Jan Kara <jack@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix failure paths in ext2_new_inode() and clean up duplicated code: -
DQUOT_DROP() was not being called if ext2_init_security() failed.
Signed-off-by: Chris Sykes <chris@sigsegv.plus.com>
Cc: Stephen Smalley <sds@epoch.ncsc.mil>
Cc: Jan Kara <jack@ucw.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch checks reserved node ID values returned by lookup and creation
operations. In case one of the reserved values is sent, return -EIO.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add information about required version of the userspace library/utilities
to Documentation/Changes. Also add pointer to this and to FUSE
documentation from Kconfig.
Thanks to Anton Altaparmakov for the reminder.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
restart pages in the journal without multi sector transfer protection
fixups (i.e. the update sequence array is empty and in fact does not
exist).
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
cifsd had been preventing software suspend from completing.
Signed-off-by: pavel@suse.de
Signed-off-by: Steve French <sfrench@us.ibm.com> lightly modified
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently rpc_mkdir/rpc_rmdir and rpc_mkpipe/mk_unlink have an API that's
a little unfortunate. They take a path relative to the rpc_pipefs root and
thus need to perform a full lookup. If you look at debugfs or usbfs they
always store the dentry for directories they created and thus can pass in
a dentry + single pathname component pair into their equivalents of the
above functions.
And in fact rpc_pipefs actually stores a dentry for all but one component so
this change not only simplifies the core rpc_pipe code but also the callers.
Unfortuntately this code path is only used by the NFS4 idmapper and
AUTH_GSSAPI for which I don't have a test enviroment. Could someone give
it a spin? It's the last bit needed before we can rework the
lookup_hash API
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Each transport implementation can now set unique bind, connect,
reestablishment, and idle timeout values. These are variables,
allowing the values to be modified dynamically. This permits
exponential backoff of any of these values, for instance.
As an example, we implement exponential backoff for the connection
reestablishment timeout.
Test-plan:
Destructive testing (unplugging the network temporarily). Connectathon
with UDP and TCP.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Get rid of the "xprt->nocong" variable.
Test-plan:
Use WAN simulation to cause sporadic bursty packet loss with UDP mounts.
Look for significant regression in performance or client stability.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Now we can fix up the last few places that use the "xprt->stream"
variable, and get rid of it from the rpc_xprt structure.
Test-plan:
Destructive testing (unplugging the network temporarily). Connectathon
with UDP and TCP.
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Implement a best practice: don't use exponential backoff when computing
retransmit timeout values on TCP connections, but simply retransmit
at regular intervals.
This also fixes a bug introduced when xprt_reset_majortimeo() was added.
Test-plan:
Enable RPC debugging and watch timeout behavior on a NFS/TCP mount.
Version: Thu, 11 Aug 2005 16:02:19 -0400
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Fixes a condition whereby the kernel is returning the non-POSIX error
EBADCOOKIE to userspace.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
[PATCH] Fix miscompare in __posix_lock_file
If an application requests the same lock twice, the
kernel should just leave the existing lock in place.
Currently, it will install a second lock of the same type.
Signed-off-by: Olaf Kirch <okir@suse.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When doing a rename on top of an existing file that is not in use,
the inode of the overwritten file will remain in the icache.
The fix is to decrement i_nlink of the overwritten inode, like we
do for unlink, rmdir etc already.
Problem diagnosed by Olaf Kirch. This patch is a slight variation
on his fix.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
since we otherwise get into a lock reversal deadlock if a read locked
runlist is passed in. In the process also change it to take an ntfs
inode instead of a vfs inode as parameter.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
nfs_readpage_release() causes an oops while accessing a file with NFS
debugging turned on (echo 32767 > /proc/sys/sunrpc/nfs_debug) and a kernel
built with CONFIG_DEBUG_SLAB.
This patch moves the debugging statement above nfs_release_request() to
avoid accessing freed memory.
Signed-off-by: Nick Wilson <njw@osdl.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix some warnings and a build error when EXT3_DEBUG is enabled.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
EXT3_MOUNT_DATA_FLAGS is not a boolean. This fixes it.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
If error occurs while in v9fs_get_sb after it calles sget, the dentry object
of the root and its inode may be freed twice -- once while handling the error
in v9fs_get_sb, and second time when v9fs_get_sb calles deactivate_super
(which in turn calls v9fs_kill_super)
The patch removes the unnecessary code that frees the root dentry and its
inode.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
v9fs_vfs_readlink allocates space for the link using __getname and
errorneously uses strlen on the newly allocated buffer to check if the buffer
passed by the user is bigger than the one returned by __getname.
The patch replaces the strlen usage to PATH_MAX, which is the actual size of
the buffers returned by __getname.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When a new session is created it uses a template object of the specified
transport type to instantiate its own copy. The code for the making a copy of
the template object was lost, and the object itself is attached to the v9fs
session. This leads to many sessions using the same transport instead of
having their own copy.
The patch puts back the code that makes a copy of the template object.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When v9fs_deserealize_fcall deserializes a Rwalk message, it incorrectly
allocates space for the qid array in the source instead of the destination
buffer.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
buf_check_size function checks if the conv buffer has enough space for the
performed operation, but it doesn't return the result back to the calling
function, only logs an error in the log.
The report-back-error functionality was lost when buf_check_size was
converted from macro to inline function. The return in the macro used to
exit from the functions that include it, after the conversion it just exits
from the inline function itself.
The patch makes buf_check_size to return flag and all functions that use
it check if they should perform the operation, or exit.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Cc: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
fs/proc/base.c: In function `proc_task_root_link':
fs/proc/base.c:364: warning: ISO C90 forbids mixed declarations and code
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
During a forensic analysis on the fat file system, I found than the result for
the last access date on this file system was different between the stat
command and the istat command (package tct-utils).
The istat command display a true date (the right windows date) but the stat
primitive (so stat, find, ls command) displays a wrong date.
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When the main thread of a thread group has done pthread_exit() and died,
the other threads are still happily running, but will not be visible
under /proc because their leader is no longer accessible.
This fixes the access control so that we can see the sub-threads again.
Signed-off-by: Sripathi Kodi <sripathik@in.ibm.com>
Acked-by: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch fixes miss-sync issue on write() system call. This updates
inode attrs flags, mtime and ctime on every comit_write call, due to
locking.
Signed-off-by: Hiroyuki Machida <machida@sm.sony.co.jp>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With the new fdtable locking rules, you have to protect fdtable with either
->file_lock or rcu_read_lock/unlock(). There are some places where we
aren't doing either. This patch fixes those places.
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add smp_mb__after_clear_bit() to unlock_kiocb()
AIO's use of wait_on_bit_lock()/wake_up_bit() forgot to add a barrier
between clearing its lock bit and calling wake_up_bit() so wake_up_bit()'s
unlocked waitqueue_active() can race. This puts AIO's use in line with the
others and the comment above wake_up_bit().
Signed-off-by: Zach Brown <zach.brown@oracle.com>
Acked-by: Benjamin LaHaise <bcrl@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Al found a potential problem in epoll_create(), where the
file->private_data member was set after fd_install(). This is obviously
wrong since another thread might do a close() on that fd# before we set the
file->private_data member. This goes over 2.6.13 and passes a few basic
tests I've done here.
(akpm: snuck in a kzalloc() cleanup too)
Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
The fix in inode.c is a real bug. It could result in undeleted, yet
unconnected files on big-endian hardware.
The others are trivial.
Signed-off-by: Dave Kleikamp <shaggy@austin.ibm.com>
Missing acct_update_integrals() and update_mem_hiwater() calls
compared to it's native counterpart.
Signed-off-by: David S. Miller <davem@davemloft.net>
Noted by David Miller:
"The bug is that free_fd_array() takes a "num" argument, but when
calling it from __free_fdtable() we're instead passing in the size in
bytes (ie. "num * sizeof(struct file *)")."
Yes it is a bug. I think I messed it up while merging newer
changes with an older version where I was using size in bytes
to optimize.
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Pavel Emelianov and Kirill Korotaev observe that fs and arch users of
security_vm_enough_memory tend to forget to vm_unacct_memory when a
failure occurs further down (typically in setup_arg_pages variants).
These are all users of insert_vm_struct, and that reservation will only
be unaccounted on exit if the vma is marked VM_ACCOUNT: which in some
cases it is (hidden inside VM_STACK_FLAGS) and in some cases it isn't.
So x86_64 32-bit and ppc64 vDSO ELFs have been leaking memory into
Committed_AS each time they're run. But don't add VM_ACCOUNT to them,
it's inappropriate to reserve against the very unlikely case that gdb
be used to COW a vDSO page - we ought to do something about that in
do_wp_page, but there are yet other inconsistencies to be resolved.
The safe and economical way to fix this is to let insert_vm_struct do
the security_vm_enough_memory check when it finds VM_ACCOUNT is set.
And the MIPS irix_brk has been calling security_vm_enough_memory before
calling do_brk which repeats it, doubly accounting and so also leaking.
Remove that, and all the fs and arch calls to security_vm_enough_memory:
give it a less misleading name later on.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-Off-By: Kirill Korotaev <dev@sw.ru>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It turns out that the BUG_ON() in fs/exec.c: de_thread() is unreliable
and can trigger due to the test itself being racy.
de_thread() does
while (atomic_read(&sig->count) > count) {
}
.....
.....
BUG_ON(!thread_group_empty(current));
but release_task does
write_lock_irq(&tasklist_lock)
__exit_signal
(this is where atomic_dec(&sig->count) is run)
__exit_sighand
__unhash_process
takes write lock on tasklist_lock
remove itself out of PIDTYPE_TGID list
write_unlock_irq(&tasklist_lock)
so there's a clear (although small) window between the
atomic_dec(&sig->count) and the actual PIDTYPE_TGID unhashing of the
thread.
And actually there is no need for all threads to have exited at this
point, so we simply kill the BUG_ON.
Big thanks to Marc Lehmann who provided the test-case.
Fixes Bug 5170 (http://bugme.osdl.org/show_bug.cgi?id=5170)
Signed-off-by: Alexander Nyberg <alexn@telia.com>
Cc: Roland McGrath <roland@redhat.com>
Cc: Andrew Morton <akpm@osdl.org>
Cc: Ingo Molnar <mingo@elte.hu>
Acked-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We could try to unlock the state lock here without having first locked it.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In the case of a lock which introduces a new lockowner, the openowner's
sequence id should be incremented, even when the operation fails, if the
error is a sequence-id-mutating error. The current code fails to do that
in some cases. Fix this by using the same sequence-id-incrementing
mechanism that all other such operations use.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
It seems more natural to move the setting of the replay_owner into the
relevant procedure instead of doing it in nfsv4_proc_compound.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Demote some printk's that look like they could be triggered by non-buggy
clients to dprintk's. (For example, stale clientid's are normal
occurrences on reboot, and on a server with a lot of clients these messages
could become annoying.)
Also remove some redundant dprintk's (e.g. no need for both STALE_CLIENTID
and its callers to do dprintks).
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
reiserfs should use mark_inode_dirty during reiserfs_file_write and
reiserfs_commit_write. This makes sure the inode is properly flagged as
dirty, which is used during O_SYNC to decide when to trigger log commits.
This patch also removes the O_SYNC check from reiserfs_commit_write, since
that gets dealt with properly at higher layers once we start using
mark_inode_dirty.
Thanks to Hifumi Hisashi <hifumi.hisashi@lab.ntt.co.jp> for catching this.
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
When open(O_CREAT) is called and the error, ENFILE, is returned, the file
may be created anyway. This is counter intuitive, against the SUS V3
specification, and may cause applications to misbehave if they are not
coded correctly to handle this semantic. The SUS V3 specification
explicitly states "No files shall be created or modified if the function
returns -1.".
The error, ENFILE, is used to indicate the system wide open file table is
full and no more file structs can be allocated.
This is due to an ordering problem. The entry in the directory is created
before the file struct is allocated. If the allocation for the file struct
fails, then the system call must return an error, but the directory entry
was already created and can not be safely removed.
The solution to this situation is relatively easy. The file struct should
be allocated before the directory entry is created. If the allocation
fails, then the error can be returned directly. If the creation of the
directory entry fails, then the file struct can be easily freed.
Signed-off-by: Peter Staubach <staubach@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
an octal number to conform to how chmod(1) works, too. Thanks to
Giuseppe Bilotta and Horst von Brand for pointing out the errors of
my ways.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
Clash due to new delete_inode behavior (the filesystem now needs to do
the truncate_inode_pages() call itself).
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use schedule_timeout_{,un}interruptible() instead of
set_current_state()/schedule_timeout() to reduce kernel size. Also use helper
functions to convert between human time units and jiffies rather than constant
HZ division to avoid rounding errors.
Signed-off-by: Nishanth Aravamudan <nacc@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Every file should #include the header with the prototypes of the global
functions it is offering.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
First one is list_for_each_entry (thanks maks), second 2 list_for_each_safe.
Signed-off-by: Maximilian Attems <janitor@sternwelten.at>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make code more readable with list_for_each_entry.
Signed-off-by: Maximilian Attems <janitor@sternwelten.at>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Use list_for_each_entry to make code more readable.
Signed-off-by: Maximilian Attems <janitor@sternwelten.at>
Signed-off-by: Domen Puncer <domen@coderock.org>
Cc: <jffs-dev@axis.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch implements a task state bit (TASK_NONINTERACTIVE), which can be
used by blocking points to mark the task's wait as "non-interactive". This
does not mean the task will be considered a CPU-hog - the wait will simply
not have an effect on the waiting task's priority - positive or negative
alike. Right now only pipe_wait() will make use of it, because it's a
common source of not-so-interactive waits (kernel compilation jobs, etc.).
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch (written by me and also containing many suggestions of Arjan van
de Ven) does a major cleanup of the spinlock code. It does the following
things:
- consolidates and enhances the spinlock/rwlock debugging code
- simplifies the asm/spinlock.h files
- encapsulates the raw spinlock type and moves generic spinlock
features (such as ->break_lock) into the generic code.
- cleans up the spinlock code hierarchy to get rid of the spaghetti.
Most notably there's now only a single variant of the debugging code,
located in lib/spinlock_debug.c. (previously we had one SMP debugging
variant per architecture, plus a separate generic one for UP builds)
Also, i've enhanced the rwlock debugging facility, it will now track
write-owners. There is new spinlock-owner/CPU-tracking on SMP builds too.
All locks have lockup detection now, which will work for both soft and hard
spin/rwlock lockups.
The arch-level include files now only contain the minimally necessary
subset of the spinlock code - all the rest that can be generalized now
lives in the generic headers:
include/asm-i386/spinlock_types.h | 16
include/asm-x86_64/spinlock_types.h | 16
I have also split up the various spinlock variants into separate files,
making it easier to see which does what. The new layout is:
SMP | UP
----------------------------|-----------------------------------
asm/spinlock_types_smp.h | linux/spinlock_types_up.h
linux/spinlock_types.h | linux/spinlock_types.h
asm/spinlock_smp.h | linux/spinlock_up.h
linux/spinlock_api_smp.h | linux/spinlock_api_up.h
linux/spinlock.h | linux/spinlock.h
/*
* here's the role of the various spinlock/rwlock related include files:
*
* on SMP builds:
*
* asm/spinlock_types.h: contains the raw_spinlock_t/raw_rwlock_t and the
* initializers
*
* linux/spinlock_types.h:
* defines the generic type and initializers
*
* asm/spinlock.h: contains the __raw_spin_*()/etc. lowlevel
* implementations, mostly inline assembly code
*
* (also included on UP-debug builds:)
*
* linux/spinlock_api_smp.h:
* contains the prototypes for the _spin_*() APIs.
*
* linux/spinlock.h: builds the final spin_*() APIs.
*
* on UP builds:
*
* linux/spinlock_type_up.h:
* contains the generic, simplified UP spinlock type.
* (which is an empty structure on non-debug builds)
*
* linux/spinlock_types.h:
* defines the generic type and initializers
*
* linux/spinlock_up.h:
* contains the __raw_spin_*()/etc. version of UP
* builds. (which are NOPs on non-debug, non-preempt
* builds)
*
* (included on UP-non-debug builds:)
*
* linux/spinlock_api_up.h:
* builds the _spin_*() APIs.
*
* linux/spinlock.h: builds the final spin_*() APIs.
*/
All SMP and UP architectures are converted by this patch.
arm, i386, ia64, ppc, ppc64, s390/s390x, x64 was build-tested via
crosscompilers. m32r, mips, sh, sparc, have not been tested yet, but should
be mostly fine.
From: Grant Grundler <grundler@parisc-linux.org>
Booted and lightly tested on a500-44 (64-bit, SMP kernel, dual CPU).
Builds 32-bit SMP kernel (not booted or tested). I did not try to build
non-SMP kernels. That should be trivial to fix up later if necessary.
I converted bit ops atomic_hash lock to raw_spinlock_t. Doing so avoids
some ugly nesting of linux/*.h and asm/*.h files. Those particular locks
are well tested and contained entirely inside arch specific code. I do NOT
expect any new issues to arise with them.
If someone does ever need to use debug/metrics with them, then they will
need to unravel this hairball between spinlocks, atomic ops, and bit ops
that exist only because parisc has exactly one atomic instruction: LDCW
(load and clear word).
From: "Luck, Tony" <tony.luck@intel.com>
ia64 fix
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arjan van de Ven <arjanv@infradead.org>
Signed-off-by: Grant Grundler <grundler@parisc-linux.org>
Cc: Matthew Wilcox <willy@debian.org>
Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Mikael Pettersson <mikpe@csd.uu.se>
Signed-off-by: Benoit Boissinot <benoit.boissinot@ens-lyon.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Andrew lost this in patch reject resolution, and never noticed, since
the compat code isn't in use on x86.
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This converts the final 20 DEFINE_SPINLOCK holdouts. (another 580 places
are already using DEFINE_SPINLOCK). Build tested on x86.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes ability to interrupt and restart operations while there
hasn't been any side-effect.
The reason: applications. There are some apps it seems that generate
signals at a fast rate. This means, that if the operation cannot make
enough progress between two signals, it will be restarted for ever. This
bug actually manifested itself with 'krusader' trying to open a file for
writing under sshfs. Thanks to Eduard Czimbalmos for the report.
The problem can be solved just by making open() uninterruptible, because in
this case it was the truncate operation that slowed down the progress. But
it's better to solve this by simply not allowing interrupts at all (except
SIGKILL), because applications don't expect file operations to be
interruptible anyway. As an added bonus the code is simplified somewhat.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds a new FSYNCDIR request, which is sent when fsync is called
on directories. This operation is available in libfuse 2.3-pre1 or
greater.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Don't change mtime/ctime/atime to local time on read/write. Rather invalidate
file attributes, so next stat() will force a GETATTR call. Bug reported by
Ben Grimm.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Make data caching behavior selectable on a per-open basis instead of
per-mount. Compatibility for the old mount options 'kernel_cache' and
'direct_io' is retained in the userspace library (version 2.4.0-pre1 or
later).
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes a long lasting "hack" in FUSE, which used a separate
channel (a file descriptor refering to a disk-file) to transfer directory
contents from userspace to the kernel.
The patch adds three new operations (OPENDIR, READDIR, RELEASEDIR), which
have semantics and implementation exactly maching the respective file
operations (OPEN, READ, RELEASE).
This simplifies the directory reading code. Also disk space is not
necessary, which can be important in embedded systems.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds support for the "direct_io" mount option of FUSE.
When this mount option is specified, the page cache is bypassed for
read and write operations. This is useful for example, if the
filesystem doesn't know the size of files before reading them, or when
any kind of caching is harmful.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Check for the presence of all mandatory mount options.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch tightens the check for allowing processes to access non-privileged
mounts. The rational is that the filesystem implementation can control the
behavior or get otherwise unavailable information of the filesystem user. If
the filesystem user process has the same uid, gid, and is not suid or sgid
application, then access is safe. Otherwise access is not allowed unless the
"allow_other" mount option is given (for which policy is controlled by the
userspace mount utility).
Thanks to everyone linux-fsdevel, especially Martin Mares who helped uncover
problems with the previous approach.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds readpages support to FUSE.
With the help of the readpages() operation multiple reads are bundled
together and sent as a single request to userspace. This can improve
reading performace.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds the extended attribute operations to FUSE.
The following operations are added:
o getxattr
o setxattr
o listxattr
o removexattr
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds miscellaneous mount options to the FUSE filesystem.
The following mount options are added:
o default_permissions: check permissions with generic_permission()
o allow_other: allow other users to access files
o allow_root: allow root to access files
o kernel_cache: don't invalidate page cache on open
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds the file operations of FUSE.
The following operations are added:
o open
o flush
o release
o fsync
o readpage
o commit_write
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds the write filesystem operations of FUSE.
The following operations are added:
o setattr
o symlink
o mknod
o mkdir
o create
o unlink
o rmdir
o rename
o link
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds the read-only filesystem operations of FUSE.
This contains the following files:
o dir.c
- directory, symlink and file-inode operations
The following operations are added:
o lookup
o getattr
o readlink
o follow_link
o directory open
o readdir
o directory release
o permission
o dentry revalidate
o statfs
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This adds the FUSE device handling functions.
This contains the following files:
o dev.c
- fuse device operations (read, write, release, poll)
- registers misc device
- support for sending requests to userspace
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch adds FUSE core.
This contains the following files:
o inode.c
- superblock operations (alloc_inode, destroy_inode, read_inode,
clear_inode, put_super, show_options)
- registers FUSE filesystem
o fuse_i.h
- private header file
Requirements
============
The most important difference between orinary filesystems and FUSE is
the fact, that the filesystem data/metadata is provided by a userspace
process run with the privileges of the mount "owner" instead of the
kernel, or some remote entity usually running with elevated
privileges.
The security implication of this is that a non-privileged user must
not be able to use this capability to compromise the system. Obvious
requirements arising from this are:
- mount owner should not be able to get elevated privileges with the
help of the mounted filesystem
- mount owner should not be able to induce undesired behavior in
other users' or the super user's processes
- mount owner should not get illegitimate access to information from
other users' and the super user's processes
These are currently ensured with the following constraints:
1) mount is only allowed to directory or file which the mount owner
can modify without limitation (write access + no sticky bit for
directories)
2) nosuid,nodev mount options are forced
3) any process running with fsuid different from the owner is denied
all access to the filesystem
1) and 2) are ensured by the "fusermount" mount utility which is a
setuid root application doing the actual mount operation.
3) is ensured by a check in the permission() method in kernel
I started thinking about doing 3) in a different way because Christoph
H. made a big deal out of it, saying that FUSE is unacceptable into
mainline in this form.
The suggested use of private namespaces would be OK, but in their
current form have many limitations that make their use impractical (as
discussed in this thread).
Suggested improvements that would address these limitations:
- implement shared subtrees
- allow a process to join an existing namespace (make namespaces
first-class objects)
- implement the namespace creation/joining in a PAM module
With all that in place the check of owner against current->fsuid may
be removed from the FUSE kernel module, without compromising the
security requirements.
Suid programs still interesting questions, since they get access even
to the private namespace causing some information leak (exact
order/timing of filesystem operations performed), giving some
ptrace-like capabilities to unprivileged users. BTW this problem is
not strictly limited to the namespace approach, since suid programs
setting fsuid and accessing users' files will succeed with the current
approach too.
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch attempts to do a better job of cleaning up after detecting errors
on the transport. This should also improve error reporting on broken
connections to servers.
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
LANL reported some issues with random crashes during mount of legacy protocol
servers (9P2000 versus 9P2000.u) -- crash was always happening in readlink
(which should never happen in legacy mode). Added some sanity conditionals to
the get_inode code which should prevent the errors LANL was seeing. Code
tested benign through regression.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Cleanup code in v9fs vfs_inode as suggested by Alexey Dobriyan. Did some
major revamping of the v9fs setattr code to remove unnecessary allocations and
clean up some dead-code.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Change magic error numbers to system defined constants in v9fs error.h As
suggested by Jan-Benedict Glaw.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This part of the patch contains debug and other misc routines.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Support for force umount
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This part of the patch contains transport routines.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Latchesar Ionkov <lucho@ionkov.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This part of the patch contains the 9P protocol functions.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This part of the patch contains VFS superblock and mapping code.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This part of the patch contains the VFS inode interfaces.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This part of the patch contains the VFS file, dentry & directory interfaces.
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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: Eric Van Hensbergen <ericvh@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
With the use of RCU in files structure, the look-up of files using fds can now
be lock-free. The lookup is protected by rcu_read_lock()/rcu_read_unlock().
This patch changes the readers to use lock-free lookup.
Signed-off-by: Maneesh Soni <maneesh@in.ibm.com>
Signed-off-by: Ravikiran Thirumalai <kiran_th@gmail.com>
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Patch to eliminate struct files_struct.file_lock spinlock on the reader side
and use rcu refcounting rcuref_xxx api for the f_count refcounter. The
updates to the fdtable are done by allocating a new fdtable structure and
setting files->fdt to point to the new structure. The fdtable structure is
protected by RCU thereby allowing lock-free lookup. For fd arrays/sets that
are vmalloced, we use keventd to free them since RCU callbacks can't sleep. A
global list of fdtable to be freed is not scalable, so we use a per-cpu list.
If keventd is already handling the current cpu's work, we use a timer to defer
queueing of that work.
Since the last publication, this patch has been re-written to avoid using
explicit memory barriers and use rcu_assign_pointer(), rcu_dereference()
premitives instead. This required that the fd information is kept in a
separate structure (fdtable) and updated atomically.
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
In order for the RCU to work, the file table array, sets and their sizes must
be updated atomically. Instead of ensuring this through too many memory
barriers, we put the arrays and their sizes in a separate structure. This
patch takes the first step of putting the file table elements in a separate
structure fdtable that is embedded withing files_struct. It also changes all
the users to refer to the file table using files_fdtable() macro. Subsequent
applciation of RCU becomes easier after this.
Signed-off-by: Dipankar Sarma <dipankar@in.ibm.com>
Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Implement a per-kiocb lock to serialise retry operations and cancel. This
is done using wait_on_bit_lock() on the KIF_LOCKED bit of kiocb->ki_flags.
Also, make the cancellation path lock the kiocb and subsequently release
all references to it if the cancel was successful. This version includes a
fix for the deadlock with __aio_run_iocbs.
Signed-off-by: Benjamin LaHaise <bcrl@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Note that other than few exceptions, most of the current filesystem and/or
drivers do not have aio cancel specifically defined (kiob->ki_cancel field
is mostly NULL). However, sys_io_cancel system call universally sets
return code to -EAGAIN. This gives applications a wrong impression that
this call is implemented but just never works. We have customer inquires
about this issue.
Changed by Benjamin LaHaise to EINVAL instead of ENOSYS
Signed-off-by: S. Wendy Cheng <wcheng@redhat.com>
Acked-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch for old autofs (version 3) cleans dentries which are not putted
after killing the automount daemon (it's analogue of recent patch for
autofs4).
Signed-off-by: Alexander Krizhanovsky <klx@yandex.ru>
Cc: Ian Kent <raven@themaw.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes the inode_post_link and inode_post_rename LSM hooks as
they are unused (and likely useless).
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch removes the inode_post_create/mkdir/mknod/symlink LSM hooks as
they are obsoleted by the new inode_init_security hook that enables atomic
inode security labeling.
If anyone sees any reason to retain these hooks, please speak now. Also,
is anyone using the post_rename/link hooks; if not, those could also be
removed.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch modifies ext3 to call the inode_init_security LSM hook to obtain
the security attribute for a newly created inode and to set the resulting
attribute on the new inode as part of the same transaction. This parallels
the existing processing for setting ACLs on newly created inodes.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch modifies ext2 to call the inode_init_security LSM hook to obtain
the security attribute for a newly created inode and to set the resulting
attribute on the new inode. This parallels the existing processing for
setting ACLs on newly created inodes.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Update the file systems in fs/ implementing a delete_inode() callback to
call truncate_inode_pages(). One implementation note: In developing this
patch I put the calls to truncate_inode_pages() at the very top of those
filesystems delete_inode() callbacks in order to retain the previous
behavior. I'm guessing that some of those could probably be optimized.
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Allow file systems supporting ->delete_inode() to call
truncate_inode_pages() on their own. OCFS2 wants this so it can query the
cluster before making a final decision on whether to wipe an inode from
disk or not. In some corner cases an inode marked on the local node via
voting may not actually get orphaned. A good example is node death before
the transaction moving the inode to the orphan dir commits to the journal.
Without this patch, the truncate_inode_pages() call in
generic_delete_inode() would discard valid data for such inodes.
During earlier discussion in the 2.6.13 merge plan thread, Christoph
Hellwig indicated that other file systems might also find this useful.
IMHO, the best solution would be to just allow ->drop_inode() to do the
cluster query but it seems that would require a substantial reworking of
that section of the code. Assuming it is safe to call write_inode_now() in
ocfs2_delete_inode() for those inodes which won't actually get wiped, this
solution should get us by for now.
Trivial testing of this patch (and a related OCFS2 update) has shown this
to avoid the corruption I'm seeing.
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
<qualifier> void * is not the same as void <qualifier> *...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
fs/ntfs/aops.c::ntfs_end_buffer_async_read() to a bit spin lock
in the first buffer head of a page.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
lock protection over the buffer submission for i/o which allows the
removal of the get_bh()/put_bh() pairs for each buffer.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
akpm@osdl.org
Andreas Gruenbacher
Latchesar Ionkov
Dave Kleikamp
Tom Zanussi
Al Viro
Linus Torvalds
Alexey Dobriyan
Anton Altaparmakov
Miklos Szeredi
Paolo 'Blaisorblade' Giarrusso
Zach Brown
Kostik Belousov
Davide Libenzi
Chris Sykes
Steve French
Trond Myklebust
Christoph Hellwig
Chuck Lever
Chuck Lever
Olaf Kirch
Nick Wilson
Glauber de Oliveira Costa
OGAWA Hirofumi
Stephane Kardas
Sripathi Kodi
Dipankar Sarma
David S. Miller
Hugh Dickins
Alexander Nyberg
Neil Brown
Chris Mason
Peter Staubach
Nishanth Aravamudan
Adrian Bunk
James Lamanna
Domen Puncer
Ingo Molnar
Kirill Korotaev
Eric Van Hensbergen
Benjamin LaHaise
Wendy Cheng
Andrew Stribblehill
Alexander Krizhanovsky
Stephen Smalley
Mark Fasheh
viro@ZenIV.linux.org.uk
Anton Altaparmakov
Nathan Scott