The handling of mount flags in set_mnt_shared() got a little tangled
up during previous cleanups, with the following problems:
* MNT_PNODE_MASK is defined as a literal constant when it should be a
bitwise xor of other MNT_* flags
* set_mnt_shared() clears and then sets MNT_SHARED (part of MNT_PNODE_MASK)
* MNT_PNODE_MASK could use a comment in mount.h
* MNT_PNODE_MASK is a terrible name, change to MNT_SHARED_MASK
This patch fixes these problems.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
path to mnt/mnt->mnt_root is no worse than that to
mnt->mnt_parent/mnt->mnt_mountpoint *and* needs no
pinning the sucker down (mnt is not going away and
mnt->mnt_root won't change)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
First of all, get_source() never results in CL_PROPAGATION
alone. We either get CL_MAKE_SHARED (for the continuation
of peer group) or CL_SLAVE (slave that is not shared) or both
(beginning of peer group among slaves). Massage the code to
make that explicit, kill CL_PROPAGATION test in clone_mnt()
(nothing sets CL_MAKE_SHARED without CL_PROPAGATION and in
clone_mnt() we are checking CL_PROPAGATION after we'd found
that there's no CL_SLAVE, so the check for CL_MAKE_SHARED
would do just as well).
Fix comments, while we are at it...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Invalidate sb->s_bdev on remount,ro.
Fixes a problem reported by Jorge Boncompte who is seeing corruption
trying to snapshot a minix filesystem image. Some filesystems modify
their metadata via a path other than the bdev buffer cache (eg. they may
use a private linear mapping for their metadata, or implement directories
in pagecache, etc). Also, file data modifications usually go to the bdev
via their own mappings.
These updates are not coherent with buffercache IO (eg. via /dev/bdev)
and never have been. However there could be a reasonable expectation that
after a mount -oremount,ro operation then the buffercache should
subsequently be coherent with previous filesystem modifications.
So invalidate the bdev mappings on a remount,ro operation to provide a
coherency point.
The problem was exposed when we switched the old rd to brd because old rd
didn't really function like a normal block device and updates to rd via
mappings other than the buffercache would still end up going into its
buffercache. But the same problem has always affected other "normal"
block devices, including loop.
[akpm@linux-foundation.org: repair comment layout]
Reported-by: "Jorge Boncompte [DTI2]" <jorge@dti2.net>
Tested-by: "Jorge Boncompte [DTI2]" <jorge@dti2.net>
Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Cleanup EXPORT* macros according to Documantation/CodingStyle.
Move EXPORT* macros to the line immediately after the closing
function brace.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
EXPORT_SYMBOL(proc_symlink);
EXPORT_SYMBOL(proc_mkdir);
EXPORT_SYMBOL(create_proc_entry);
EXPORT_SYMBOL(proc_create_data);
EXPORT_SYMBOL(remove_proc_entry);
Those EXPORT_SYMBOL shouldn't be in fs/proc/root.c,
should be in fs/proc/generic.c.
Signed-off-by: Helight.Xu <helight.xu@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Remove the EXPORT_UNUSED_SYMBOL of simple_prepare_write
Collapse simple_prepare_write into it's only caller, though
making it simpler and clearer to understand.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* simple_commit_write was only called by simple_write_end.
Open coding it makes it tiny bit less heavy on the arithmetic and
much more readable.
* While at it use zero_user() for clearing a partial page.
* While at it add a docbook comment for simple_write_end.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This reverts commit 213614d583.
Alas, ->d_revalidate() can't rely on ->lookup() finishing what
it's started; if d_alloc() in do_lookup() fails, we are not going
to call ->lookup() at all.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
cachefiles_delete_object() can race with rename. It gets the parent directory
of the object it's asked to delete, then locks it - but rename may have changed
the object's parent between the get and the completion of the lock.
However, if such a circumstance is detected, we abandon our attempt to delete
the object - since it's no longer in the index key path, it won't be seen
again by lookups of that key. The assumption is that cachefilesd may have
culled it by renaming it to the graveyard for later destruction.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
commit 1e41568d73 ("Take ima_path_check()
in nfsd past dentry_open() in nfsd_open()") moved this code back to its
original location but missed the "else".
Signed-off-by: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Make sure that automount "symlinks" are followed regardless of LOOKUP_FOLLOW;
it should have no effect on them.
Cc: stable@kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Al Viro
Valerie Aurora
Nick Piggin
H Hartley Sweeten
Helight.Xu
Boaz Harrosh
Michael Neuling
David Howells
Chuck Ebbert