fsync_buffers_list() and sync_dirty_buffer() both issue async writes and
then immediately wait on them. Conceptually, that makes them sync writes
and we should treat them as such so that the IO schedulers can handle
them appropriately.
This patch fixes a write starvation issue that Lin Ming reported, where
xx is stuck for more than 2 minutes because of a large number of
synchronous IO in the system:
INFO: task kjournald:20558 blocked for more than 120 seconds.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this
message.
kjournald D ffff810010820978 6712 20558 2
ffff81022ddb1d10 0000000000000046 ffff81022e7baa10 ffffffff803ba6f2
ffff81022ecd0000 ffff8101e6dc9160 ffff81022ecd0348 000000008048b6cb
0000000000000086 ffff81022c4e8d30 0000000000000000 ffffffff80247537
Call Trace:
[<ffffffff803ba6f2>] kobject_get+0x12/0x17
[<ffffffff80247537>] getnstimeofday+0x2f/0x83
[<ffffffff8029c1ac>] sync_buffer+0x0/0x3f
[<ffffffff8066d195>] io_schedule+0x5d/0x9f
[<ffffffff8029c1e7>] sync_buffer+0x3b/0x3f
[<ffffffff8066d3f0>] __wait_on_bit+0x40/0x6f
[<ffffffff8029c1ac>] sync_buffer+0x0/0x3f
[<ffffffff8066d48b>] out_of_line_wait_on_bit+0x6c/0x78
[<ffffffff80243909>] wake_bit_function+0x0/0x23
[<ffffffff8029e3ad>] sync_dirty_buffer+0x98/0xcb
[<ffffffff8030056b>] journal_commit_transaction+0x97d/0xcb6
[<ffffffff8023a676>] lock_timer_base+0x26/0x4b
[<ffffffff8030300a>] kjournald+0xc1/0x1fb
[<ffffffff802438db>] autoremove_wake_function+0x0/0x2e
[<ffffffff80302f49>] kjournald+0x0/0x1fb
[<ffffffff802437bb>] kthread+0x47/0x74
[<ffffffff8022de51>] schedule_tail+0x28/0x5d
[<ffffffff8020cac8>] child_rip+0xa/0x12
[<ffffffff80243774>] kthread+0x0/0x74
[<ffffffff8020cabe>] child_rip+0x0/0x12
Lin Ming confirms that this patch fixes the issue. I've run tests with
it for the past week and no ill effects have been observed, so I'm
proposing it for inclusion into 2.6.26.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
fl_insert and fl_remove are not used right now in the kernel. Remove them.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This patch introduces memory_read_from_buffer().
The only difference between memory_read_from_buffer() and
simple_read_from_buffer() is which address space the function copies to.
simple_read_from_buffer copies to user space memory.
memory_read_from_buffer copies to normal memory.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Doug Warzecha <Douglas_Warzecha@dell.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Matt Domsch <Matt_Domsch@dell.com>
Cc: Abhay Salunke <Abhay_Salunke@dell.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Markus Rechberger <markus.rechberger@amd.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Bob Moore <robert.moore@intel.com>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Len Brown <lenb@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Cc: Michael Holzheu <holzheu@de.ibm.com>
Cc: Brian King <brking@us.ibm.com>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Andrew Vasquez <linux-driver@qlogic.com>
Cc: Seokmann Ju <seokmann.ju@qlogic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
generic_file_splice_write() duplicates remove_suid() just because it
doesn't hold i_mutex. But it grabs i_mutex inside splice_from_pipe()
anyway, so this is rather pointless.
Move locking to generic_file_splice_write() and call remove_suid() and
__splice_from_pipe() instead.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
And with that last patch to affs killing the last put_inode instance we
can finally, after many years of transition kill this racy and awkward
interface.
(It's kinda funny that even the description in
Documentation/filesystems/vfs.txt was entirely wrong..)
Also remove a very misleading comment above the defintion of
struct super_operations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Make the needlessly global vfs_ioctl() static.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make the needlessly global __put_super() static.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Convert XIP to support non-struct page backed memory, using VM_MIXEDMAP for
the user mappings.
This requires the get_xip_page API to be changed to an address based one.
Improve the API layering a little bit too, while we're here.
This is required in order to support XIP filesystems on memory that isn't
backed with struct page (but memory with struct page is still supported too).
Signed-off-by: Nick Piggin <npiggin@suse.de>
Acked-by: Carsten Otte <cotte@de.ibm.com>
Cc: Jared Hulbert <jaredeh@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Alter the block device ->direct_access() API to work with the new
get_xip_mem() API (that requires both kaddr and pfn are returned).
Some architectures will not do the right thing in their virt_to_page() for use
by XIP (to translate from the kernel virtual address returned by
direct_access(), to a user mappable pfn in XIP's page fault handler.
However, we can't switch it to just return the pfn and not the kaddr, because
we have no good way to get a kva from a pfn, and XIP requires the kva for its
read(2) and write(2) handlers. So we have to return both.
Signed-off-by: Jared Hulbert <jaredeh@gmail.com>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-mm@kvack.org
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The file_lock structure is used both as a heavy-weight representation of
an active lock, with pointers to reference-counted structures, etc., and
as a simple container for parameters that describe a file lock.
The conflicting lock returned from __posix_lock_file is an example of
the latter; so don't call the filesystem or lock manager callbacks when
copying to it. This also saves the need for an unnecessary
locks_init_lock in the nfsv4 server.
Thanks to Trond for pointing out the error.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
* let unshare_files() give caller the displaced files_struct
* don't bother with grabbing reference only to drop it in the
caller if it hadn't been shared in the first place
* in that form unshare_files() is trivially implemented via
unshare_fd(), so we eliminate the duplicate logics in fork.c
* reset_files_struct() is not just only called for current;
it will break the system if somebody ever calls it for anything
else (we can't modify ->files of somebody else). Lose the
task_struct * argument.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
There have been a few oopses caused by 'struct file's with NULL f_vfsmnts.
There was also a set of potentially missed mnt_want_write()s from
dentry_open() calls.
This patch provides a very simple debugging framework to catch these kinds of
bugs. It will WARN_ON() them, but should stop us from having any oopses or
mnt_writer count imbalances.
I'm quite convinced that this is a good thing because it found bugs in the
stuff I was working on as soon as I wrote it.
[hch: made it conditional on a debug option.
But it's still a little bit too ugly]
[hch: merged forced remount r/o fix from Dave and akpm's fix for the fix]
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
open_namei() will, in the future, need to take mount write counts
over its creation and truncation (via may_open()) operations. It
needs to keep these write counts until any potential filp that is
created gets __fput()'d.
This gets complicated in the error handling and becomes very murky
as to how far open_namei() actually got, and whether or not that
mount write count was taken. That makes it a bad interface.
All that the current do_filp_open() really does is allocate the
nameidata on the stack, then call open_namei().
So, this merges those two functions and moves filp_open() over
to namei.c so it can be close to its buddy: do_filp_open(). It
also gets a kerneldoc comment in the process.
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This patch makes the needlessly global struct def_blk_aops static.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Jens Axboe <axboe@carl.home.kernel.dk>
Add explanation of I_DIRTY_DATASYNC bit.
Signed-off-by: Jan Kara <jack@suse.cz>
Cc: Joern Engel <joern@logfs.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There is an outdated comment in serial_core.c also fixed.
Signed-off-by: Denis Cheng <crquan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a new s_options field to struct super_block. Filesystems can save
mount options passed to them in mount or remount. It is automatically
freed when the superblock is destroyed.
A new helper function, generic_show_options() is introduced, which uses
this field to display the mount options in /proc/mounts.
Another helper function, save_mount_options() may be used by
filesystems to save the options in the super block.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
do_generic_mapping_read was used by gfs2 for internals reads, but this use
of the interface was rather suboptimal (as was the whole interface) and has
been replaced by an internal helper now. This patch kills
do_generic_mapping_read and surrounding damage in preparation of additional
cleanups for the buffered read path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
simple_attr_close implementes ->release so it should be named accordingly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: <stefano.brivio@polimi.it>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg KH <greg@kroah.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sometimes simple attributes might need to return an error, e.g. for
acquiring a mutex interruptibly. In fact we have that situation in
spufs already which is the original user of the simple attributes. This
patch merged the temporarily forked attributes in spufs back into the
main ones and allows to return errors.
[akpm@linux-foundation.org: build fix]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: <stefano.brivio@polimi.it>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg KH <greg@kroah.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove the old iget() call and the read_inode() superblock operation it uses
as these are really obsolete, and the use of read_inode() does not produce
proper error handling (no distinction between ENOMEM and EIO when marking an
inode bad).
Furthermore, this removes the temptation to use iget() to find an inode by
number in a filesystem from code outside that filesystem.
iget_locked() should be used instead. A new function is added in an earlier
patch (iget_failed) that is to be called to mark an inode as bad, unlock it
and release it should the get routine fail. Mark iget() and read_inode() as
being obsolete and remove references to them from the documentation.
Typically a filesystem will be modified such that the read_inode function
becomes an internal iget function, for example the following:
void thingyfs_read_inode(struct inode *inode)
{
...
}
would be changed into something like:
struct inode *thingyfs_iget(struct super_block *sp, unsigned long ino)
{
struct inode *inode;
int ret;
inode = iget_locked(sb, ino);
if (!inode)
return ERR_PTR(-ENOMEM);
if (!(inode->i_state & I_NEW))
return inode;
...
unlock_new_inode(inode);
return inode;
error:
iget_failed(inode);
return ERR_PTR(ret);
}
and then thingyfs_iget() would be called rather than iget(), for example:
ret = -EINVAL;
inode = iget(sb, ino);
if (!inode || is_bad_inode(inode))
goto error;
becomes:
inode = thingyfs_iget(sb, ino);
if (IS_ERR(inode)) {
ret = PTR_ERR(inode);
goto error;
}
Note that is_bad_inode() does not need to be called. The error returned by
thingyfs_iget() should render it unnecessary.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Introduce a function to register failure in an inode construction path. This
includes marking the inode under construction as bad, unlocking it and
releasing it.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rename old vfs_ioctl to do_ioctl, because the comment above it clearly
indicates that it is an internal function not to be exported to modules;
therefore it should have a more traditional do_XXX name. The new do_ioctl
is exported in fs.h but not to modules.
Rename the old do_ioctl to vfs_ioctl because the names vfs_XXX should
preferably be reserved to callable VFS functions which modules may call, as
many other vfs_XXX functions already do. Export the new vfs_ioctl to GPL
modules so others can use it (including Unionfs and eCryptfs). Add DocBook
for new vfs_ioctl.
[akpm@linux-foundation.org: fix build]
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
NR_OPEN (historically set to 1024*1024) actually forbids processes to open
more than 1024*1024 handles.
Unfortunatly some production servers hit the not so 'ridiculously high
value' of 1024*1024 file descriptors per process.
Changing NR_OPEN is not considered safe because of vmalloc space potential
exhaust.
This patch introduces a new sysctl (/proc/sys/fs/nr_open) wich defaults to
1024*1024, so that admins can decide to change this limit if their workload
needs it.
[akpm@linux-foundation.org: export it for sparc64]
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use list_for_each_entry_reverse for super_blocks list and remove
unused sb_entry macro.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After some archeology (see http://logfs.org/logfs/inode_state_bits) I
finally figured out what the three I_DIRTY bits do. Maybe others would
prefer less effort to reach this insight.
Signed-off-by: Joern Engel <joern@logfs.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ad a proper prototype for migration_init() in include/linux/fs.h
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
fcntl(F_GETLK,..) can return pid of process for not current pid namespace
(if process is belonged to the several namespaces). It is true also for
pids in /proc/locks. So correct behavior is saving pointer to the struct
pid of the process lock owner.
Signed-off-by: Vitaliy Gusev <vgusev@openvz.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This patch adds 64-bit inode version support to ext4. The lower 32 bits
are stored in the osd1.linux1.l_i_version field while the high 32 bits
are stored in the i_version_hi field newly created in the ext4_inode.
This field is incremented in case the ext4_inode is large enough. A
i_version mount option has been added to enable the feature.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Andreas Dilger <adilger@clusterfs.com>
Signed-off-by: Kalpak Shah <kalpak@clusterfs.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Jean Noel Cordenner <jean-noel.cordenner@bull.net>
The i_version field of the inode is changed to be a 64-bit counter that
is set on every inode creation and that is incremented every time the
inode data is modified (similarly to the "ctime" time-stamp).
The aim is to fulfill a NFSv4 requirement for rfc3530.
This first part concerns the vfs, it converts the 32-bit i_version in
the generic inode to a 64-bit, a flag is added in the super block in
order to check if the feature is enabled and the i_version is
incremented in the vfs.
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: Jean Noel Cordenner <jean-noel.cordenner@bull.net>
Signed-off-by: Kalpak Shah <kalpak@clusterfs.com>
This also renames fs_subsys to fs_kobj to catch all current users with a
build error instead of a build warning which can easily be missed.
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Now that nfsd has stopped writing to the find_exported_dentry member we an
mark the export_operations const
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Neil Brown <neilb@suse.de>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: <linux-ext4@vger.kernel.org>
Cc: Dave Kleikamp <shaggy@austin.ibm.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: David Chinner <dgc@sgi.com>
Cc: Timothy Shimmin <tes@sgi.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Hugh Dickins <hugh@veritas.com>
Cc: Chris Mason <mason@suse.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: "Vladimir V. Saveliev" <vs@namesys.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Get a snapshot of a subtree, creating private clones of vfsmounts
for all its components and release such snapshot resp.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This flag tells the .get_sb callback that this is a kern_mount() call so that
it can trust *data pointer to be valid in-kernel one. If this flag is passed
from the user process, it is cleared since the *data pointer is not a valid
kernel object.
Running a few steps forward - this will be needed for proc to create the
superblock and store a valid pid namespace on it during the namespace
creation. The reason, why the namespace cannot live without proc mount is
described in the appropriate patch.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Declarations go into headers.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Ram Pai <linuxram@us.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a new attribute flag ATTR_OPEN, with the meaning: "truncation was
initiated by open() due to the O_TRUNC flag".
This way filesystems wanting to implement truncation within their ->open()
method can ignore such truncate requests.
This is a quick & dirty hack, but it comes for free.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andreas Dilger <adilger@clusterfs.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Implement file posix capabilities. This allows programs to be given a
subset of root's powers regardless of who runs them, without having to use
setuid and giving the binary all of root's powers.
This version works with Kaigai Kohei's userspace tools, found at
http://www.kaigai.gr.jp/index.php. For more information on how to use this
patch, Chris Friedhoff has posted a nice page at
http://www.friedhoff.org/fscaps.html.
Changelog:
Nov 27:
Incorporate fixes from Andrew Morton
(security-introduce-file-caps-tweaks and
security-introduce-file-caps-warning-fix)
Fix Kconfig dependency.
Fix change signaling behavior when file caps are not compiled in.
Nov 13:
Integrate comments from Alexey: Remove CONFIG_ ifdef from
capability.h, and use %zd for printing a size_t.
Nov 13:
Fix endianness warnings by sparse as suggested by Alexey
Dobriyan.
Nov 09:
Address warnings of unused variables at cap_bprm_set_security
when file capabilities are disabled, and simultaneously clean
up the code a little, by pulling the new code into a helper
function.
Nov 08:
For pointers to required userspace tools and how to use
them, see http://www.friedhoff.org/fscaps.html.
Nov 07:
Fix the calculation of the highest bit checked in
check_cap_sanity().
Nov 07:
Allow file caps to be enabled without CONFIG_SECURITY, since
capabilities are the default.
Hook cap_task_setscheduler when !CONFIG_SECURITY.
Move capable(TASK_KILL) to end of cap_task_kill to reduce
audit messages.
Nov 05:
Add secondary calls in selinux/hooks.c to task_setioprio and
task_setscheduler so that selinux and capabilities with file
cap support can be stacked.
Sep 05:
As Seth Arnold points out, uid checks are out of place
for capability code.
Sep 01:
Define task_setscheduler, task_setioprio, cap_task_kill, and
task_setnice to make sure a user cannot affect a process in which
they called a program with some fscaps.
One remaining question is the note under task_setscheduler: are we
ok with CAP_SYS_NICE being sufficient to confine a process to a
cpuset?
It is a semantic change, as without fsccaps, attach_task doesn't
allow CAP_SYS_NICE to override the uid equivalence check. But since
it uses security_task_setscheduler, which elsewhere is used where
CAP_SYS_NICE can be used to override the uid equivalence check,
fixing it might be tough.
task_setscheduler
note: this also controls cpuset:attach_task. Are we ok with
CAP_SYS_NICE being used to confine to a cpuset?
task_setioprio
task_setnice
sys_setpriority uses this (through set_one_prio) for another
process. Need same checks as setrlimit
Aug 21:
Updated secureexec implementation to reflect the fact that
euid and uid might be the same and nonzero, but the process
might still have elevated caps.
Aug 15:
Handle endianness of xattrs.
Enforce capability version match between kernel and disk.
Enforce that no bits beyond the known max capability are
set, else return -EPERM.
With this extra processing, it may be worth reconsidering
doing all the work at bprm_set_security rather than
d_instantiate.
Aug 10:
Always call getxattr at bprm_set_security, rather than
caching it at d_instantiate.
[morgan@kernel.org: file-caps clean up for linux/capability.h]
[bunk@kernel.org: unexport cap_inode_killpriv]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Andrew Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morgan <morgan@kernel.org>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I_LOCK was used for several unrelated purposes, which caused deadlock
situations in certain filesystems as a side effect. One of the purposes
now uses the new I_SYNC bit.
Also document the various bits and change their order from historical to
logical.
[bunk@stusta.de: make fs/inode.c:wake_up_inode() static]
Signed-off-by: Joern Engel <joern@wohnheim.fh-wedel.de>
Cc: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: David Chinner <dgc@sgi.com>
Cc: Anton Altaparmakov <aia21@cam.ac.uk>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
NTFS's if-condition on dirty inodes is not complete. Fix it with
sb_has_dirty_inodes().
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Ken Chen <kenchen@google.com>
Signed-off-by: Fengguang Wu <wfg@mail.ustc.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Current -mm tree has bucketful of bug fixes in periodic writeback path.
However, we still hit a glitch where dirty pages on a given inode aren't
completely flushed to the disk, and system will accumulate large amount of
dirty pages beyond what dirty_expire_interval is designed for.
The problem is __sync_single_inode() will move an inode to sb->s_dirty list
even when there are more pending dirty pages on that inode. If there is
another inode with a small number of dirty pages, we hit a case where the loop
iteration in wb_kupdate() terminates prematurely because wbc.nr_to_write > 0.
Thus leaving the inode that has large amount of dirty pages behind and it has
to wait for another dirty_writeback_interval before we flush it again. We
effectively only write out MAX_WRITEBACK_PAGES every dirty_writeback_interval.
If the rate of dirtying is sufficiently high, the system will start
accumulate a large number of dirty pages.
So fix it by having another sb->s_more_io list on which to park the inode
while we iterate through sb->s_io and to allow each dirty inode which resides
on that sb to have an equal chance of flushing some amount of dirty pages.
Signed-off-by: Ken Chen <kenchen@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix f_version type: should be u64 instead of long
There is a type inconsistency between struct inode i_version and struct file
f_version.
fs.h:
struct inode
u64 i_version;
and
struct file
unsigned long f_version;
Users do:
fs/ext3/dir.c:
if (filp->f_version != inode->i_version) {
So why isn't f_version a u64 ? It becomes a problem if versions gets
higher than 2^32 and we are on an architecture where longs are 32 bits.
This patch changes the f_version type to u64, and updates the users accordingly.
It applies to 2.6.23-rc2-mm2.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Martin Bligh <mbligh@google.com>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>
Cc: Al Viro <viro@ftp.linux.org.uk>
Cc: <linux-ext4@vger.kernel.org>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
simple_commit_write() can now become static.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jens Axboe