This will support a upcoming request where two related values need to be
updated atomically.
This was done without a union in the OrangeFS server source already. Since
that will break the kernel protocol, it has been fixed there and done here
in a way that does not break the kernel protocol.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
This has been dormant code for many years. Parts of it were removed from
the OrangeFS kernel code when it went into mainline. These bits were missed.
Now the readahead cache has been resurrected in the OrangeFS userspace
portions. It was renamed there, since it doesn't really have anything to do
with mmap specifically, so it will be renamed here.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
The userspace component attempts to do this, but this will prevent
us from even needing to go into userspace to satisfy certain getattr
requests.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Pull vfs updates from Al Viro:
"Assorted cleanups and fixes.
Probably the most interesting part long-term is ->d_init() - that will
have a bunch of followups in (at least) ceph and lustre, but we'll
need to sort the barrier-related rules before it can get used for
really non-trivial stuff.
Another fun thing is the merge of ->d_iput() callers (dentry_iput()
and dentry_unlink_inode()) and a bunch of ->d_compare() ones (all
except the one in __d_lookup_lru())"
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
fs/dcache.c: avoid soft-lockup in dput()
vfs: new d_init method
vfs: Update lookup_dcache() comment
bdev: get rid of ->bd_inodes
Remove last traces of ->sync_page
new helper: d_same_name()
dentry_cmp(): use lockless_dereference() instead of smp_read_barrier_depends()
vfs: clean up documentation
vfs: document ->d_real()
vfs: merge .d_select_inode() into .d_real()
unify dentry_iput() and dentry_unlink_inode()
binfmt_misc: ->s_root is not going anywhere
drop redundant ->owner initializations
ufs: get rid of redundant checks
orangefs: constify inode_operations
missed comment updates from ->direct_IO() prototype change
file_inode(f)->i_mapping is f->f_mapping
trim fsnotify hooks a bit
9p: new helper - v9fs_parent_fid()
debugfs: ->d_parent is never NULL or negative
...
Merge updates from Andrew Morton:
- a few misc bits
- ocfs2
- most(?) of MM
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (125 commits)
thp: fix comments of __pmd_trans_huge_lock()
cgroup: remove unnecessary 0 check from css_from_id()
cgroup: fix idr leak for the first cgroup root
mm: memcontrol: fix documentation for compound parameter
mm: memcontrol: remove BUG_ON in uncharge_list
mm: fix build warnings in <linux/compaction.h>
mm, thp: convert from optimistic swapin collapsing to conservative
mm, thp: fix comment inconsistency for swapin readahead functions
thp: update Documentation/{vm/transhuge,filesystems/proc}.txt
shmem: split huge pages beyond i_size under memory pressure
thp: introduce CONFIG_TRANSPARENT_HUGE_PAGECACHE
khugepaged: add support of collapse for tmpfs/shmem pages
shmem: make shmem_inode_info::lock irq-safe
khugepaged: move up_read(mmap_sem) out of khugepaged_alloc_page()
thp: extract khugepaged from mm/huge_memory.c
shmem, thp: respect MADV_{NO,}HUGEPAGE for file mappings
shmem: add huge pages support
shmem: get_unmapped_area align huge page
shmem: prepare huge= mount option and sysfs knob
mm, rmap: account shmem thp pages
...
Vladimir has noticed that we might declare memcg oom even during
readahead because read_pages only uses GFP_KERNEL (with mapping_gfp
restriction) while __do_page_cache_readahead uses
page_cache_alloc_readahead which adds __GFP_NORETRY to prevent from
OOMs. This gfp mask discrepancy is really unfortunate and easily
fixable. Drop page_cache_alloc_readahead() which only has one user and
outsource the gfp_mask logic into readahead_gfp_mask and propagate this
mask from __do_page_cache_readahead down to read_pages.
This alone would have only very limited impact as most filesystems are
implementing ->readpages and the common implementation mpage_readpages
does GFP_KERNEL (with mapping_gfp restriction) again. We can tell it to
use readahead_gfp_mask instead as this function is called only during
readahead as well. The same applies to read_cache_pages.
ext4 has its own ext4_mpage_readpages but the path which has pages !=
NULL can use the same gfp mask. Btrfs, cifs, f2fs and orangefs are
doing a very similar pattern to mpage_readpages so the same can be
applied to them as well.
[akpm@linux-foundation.org: coding-style fixes]
[mhocko@suse.com: restrict gfp mask in mpage_alloc]
Link: http://lkml.kernel.org/r/20160610074223.GC32285@dhcp22.suse.cz
Link: http://lkml.kernel.org/r/1465301556-26431-1-git-send-email-mhocko@kernel.org
Signed-off-by: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Cc: Chris Mason <clm@fb.com>
Cc: Steve French <sfrench@samba.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Jan Kara <jack@suse.cz>
Cc: Mike Marshall <hubcap@omnibond.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Changman Lee <cm224.lee@samsung.com>
Cc: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In orangefs_inode_getxattr(), an fsuid is written to dmesg. The kuid is
converted to a userspace uid via from_kuid(current_user_ns(), [...]), but
since dmesg is global, init_user_ns should be used here instead.
In copy_attributes_from_inode(), op_alloc() and fill_default_sys_attrs(),
upcall structures are populated with uids/gids that have been mapped into
the caller's namespace. However, those upcall structures are read by
another process (the userspace filesystem driver), and that process might
be running in another namespace. This effectively lets any user spoof its
uid and gid as seen by the userspace filesystem driver.
To fix the second issue, I just construct the opcall structures with
init_user_ns uids/gids and require the filesystem server to run in the
init namespace. Since orangefs is full of global state anyway (as the error
message in DUMP_DEVICE_ERROR explains, there can only be one userspace
orangefs filesystem driver at once), that shouldn't be a problem.
[
Why does orangefs even exist in the kernel if everything does upcalls into
userspace? What does orangefs do that couldn't be done with the FUSE
interface? If there is no good answer to those questions, I'd prefer to see
orangefs kicked out of the kernel. Can that be done for something that
shipped in a release?
According to commit f7ab093f74 ("Orangefs: kernel client part 1"), they
even already have a FUSE daemon, and the only rational reason (apart from
"but most of our users report preferring to use our kernel module instead")
given for not wanting to use FUSE is one "in-the-works" feature that could
probably be integated into FUSE instead.
]
This patch has been compile-tested.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Mike,
On Fri, Jun 3, 2016 at 9:44 PM, Mike Marshall <hubcap@omnibond.com> wrote:
> We use the return value in this one line you changed, our userspace code gets
> ill when we send it (-ENOMEM +1) as a key length...
ah, my mistake. Here's a fixed version.
Thanks,
Andreas
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Orangefs has a catch-all xattr handler that effectively does what the
trusted handler does already.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
The ORANGEFS_XATTR_INDEX_ defines are unused; the ORANGEFS_XATTR_NAME_
defines only obfuscate the code.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Cleanups:
- remove an unused variable from orangefs_readdir.
- clean up printk wrapper used for ofs "gossip" debugging.
- clean up truncate ctime and mtime setting in inode.c
- remove a useless null check found by coccinelle.
- optimize some memcpy/memset boilerplate code.
- remove some useless sanity checks from xattr.c
Fix:
- fix a potential strncpy vulnerability.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)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=ZRlK
-----END PGP SIGNATURE-----
Merge tag 'for-linus-4.6-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux
Pull orangefs fixes from Mike Marshall:
"Orangefs cleanups and a strncpy vulnerability fix.
Cleanups:
- remove an unused variable from orangefs_readdir.
- clean up printk wrapper used for ofs "gossip" debugging.
- clean up truncate ctime and mtime setting in inode.c
- remove a useless null check found by coccinelle.
- optimize some memcpy/memset boilerplate code.
- remove some useless sanity checks from xattr.c
Fix:
- fix a potential strncpy vulnerability"
* tag 'for-linus-4.6-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
orangefs: remove unused variable
orangefs: Add KERN_<LEVEL> to gossip_<level> macros
orangefs: strncpy -> strscpy
orangefs: clean up truncate ctime and mtime setting
Orangefs: fix ifnullfree.cocci warnings
Orangefs: optimize boilerplate code.
Orangefs: xattr.c cleanup
Emit the logging messages at the appropriate levels.
Miscellanea:
o Change format to fmt
o Use the more common ##__VA_ARGS__
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
It would have been possible for a rogue client-core to send in a symlink
target which is not NUL terminated. This returns EIO if the client-core
gives us corrupt data.
Leave debugfs and superblock code as is for now.
Other dcache.c and namei.c strncpy instances are safe because
ORANGEFS_NAME_MAX = NAME_MAX + 1; there is always enough space for a
name plus a NUL byte.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
The ctime and mtime are always updated on a successful ftruncate and
only updated on a successful truncate where the size changed.
We handle the ``if the size changed'' bit.
This matches FUSE's behavior.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
fs/orangefs/orangefs-debugfs.c:130:2-26: WARNING: NULL check before freeing functions like kfree, debugfs_remove, debugfs_remove_recursive or usb_free_urb is not needed. Maybe consider reorganizing relevant code to avoid passing NULL values.
NULL check before some freeing functions is not needed.
Based on checkpatch warning
"kfree(NULL) is safe this check is probably not required"
and kfreeaddr.cocci by Julia Lawall.
Generated by: scripts/coccinelle/free/ifnullfree.cocci
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Suggested by David Binderman <dcb314@hotmail.com>
The former can potentially be a performance win over the latter.
memcpy(d, s, len);
memset(d+len, c, size-len);
memset(d, c, size);
memcpy(d, s, len);
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
1. It is nonsense to test for negative size_t, suggested by
David Binderman <dcb314@hotmail.com>
2. By the time Orangefs gets called, the vfs has ensured that
name != NULL, and that buffer and size are sane.
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Merge PAGE_CACHE_SIZE removal patches from Kirill Shutemov:
"PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.
This promise never materialized. And unlikely will.
Let's stop pretending that pages in page cache are special. They are
not.
The first patch with most changes has been done with coccinelle. The
second is manual fixups on top.
The third patch removes macros definition"
[ I was planning to apply this just before rc2, but then I spaced out,
so here it is right _after_ rc2 instead.
As Kirill suggested as a possibility, I could have decided to only
merge the first two patches, and leave the old interfaces for
compatibility, but I'd rather get it all done and any out-of-tree
modules and patches can trivially do the converstion while still also
working with older kernels, so there is little reason to try to
maintain the redundant legacy model. - Linus ]
* PAGE_CACHE_SIZE-removal:
mm: drop PAGE_CACHE_* and page_cache_{get,release} definition
mm, fs: remove remaining PAGE_CACHE_* and page_cache_{get,release} usage
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.
This promise never materialized. And unlikely will.
We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE. And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.
Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.
Let's stop pretending that pages in page cache are special. They are
not.
The changes are pretty straight-forward:
- <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;
- PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};
- page_cache_get() -> get_page();
- page_cache_release() -> put_page();
This patch contains automated changes generated with coccinelle using
script below. For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.
The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.
There are few places in the code where coccinelle didn't reach. I'll
fix them manually in a separate patch. Comments and documentation also
will be addressed with the separate patch.
virtual patch
@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E
@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT
@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE
@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK
@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)
@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)
@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This was quite an oversight. After a readdir, the module could not be
unloaded, the number of slots is wrong, and memory near the slot bitmap
is possibly corrupt. Oops.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
* switch orangefs_remount() to taking ORANGEFS_SB(sb) instead of sb
* remove from the list _before_ orangefs_unmount() - request_mutex
in the latter will make sure that nothing observed in the loop in
ORANGEFS_DEV_REMOUNT_ALL handling will get freed until the end
of loop
* on removal, keep the forward pointer and zero the back one. That
way we can drop and regain the spinlock in the loop body (again,
ORANGEFS_DEV_REMOUNT_ALL one) and still be able to get to the
rest of the list.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Error should only be returned if nothing had been read/written.
Otherwise we need to report a short read/write instead.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
a) open files can't have NULL inodes
b) it's SEEK_END, not ORANGEFS_SEEK_END; no need to get cute.
c) make_bad_inode() on lseek()?
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
just have it return the slot number or -E... - the caller checks
the sign anyway
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
no point, really - we couldn't keep those across the calls of
getdents(); it would be too easy to DoS, having all slots exhausted.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Everything else setting inode->i_ values is in there.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
This is motivated by orangefs_inode_old_getattr's habit of writing over
live inodes.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Previously the client-core detected this condition by sheer luck!
Since we used strncpy, no NUL byte would be included on the name. The
client-core would call strlen, which would read past the end of its
buffer, but return a number large enough that the client-core would
return ENAMETOOLONG.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Al Viro has cleaned up the way ops are processed and waited for,
now orangefs.txt has an overview of how it works. Several recent
related commits have added to the comments in the code as well.
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
orangefs contains a helper function to calculate the difference
between two timeval structures. We are trying to remove all
instances of timespec from the kernel, and this one is not
used at all, so let's remove it now.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
The new orangefs code uses a helper function to read a time field to
its private structures from struct iattr. This will conflict with the
move to 64-bit timestamps in the kernel and is generally not necessary.
This replaces the conversion with a simple cast to time64_t that shows
what is going on. As the orangefs-internal representation already uses
64-bit timestamps, there should be no ambiguity to negative values,
and the cast ensures that we treat them as times before 1970 on both
32-bit and 64-bit architectures, rather than times after 2038. This
patch keeps that behavior.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Size and type are read-only and not in the mask. The times were left
unset despite being in the mask.
We zero-fill the times since the server will fill them in and we will
get the correct time when we fill the inode with getattr.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
I have verified that there is nothing in the userspace daemon version we
are implementing this protocol against that ever looks at this field.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
We only need it while the service operation is actually in progress
since it is only used to co-ordinate the client-core's memory use. The
kernel allocates its own space.
Also clean up some comments which mislead the reader into thinking
the readdir buffers are shared memory.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
* turn all those list_del(&op->list) into list_del_init()
* don't pick ops that are already given up in control device
->read()/->write_iter().
* have orangefs_clean_interrupted_operation() notice if op is currently
being copied to/from daemon (by said ->read()/->write_iter()) and
wait for that to finish.
* when we are done copying to/from daemon and find that it had been
given up while we were doing that, wake the waiting ..._clean_interrupted_...
As the result, we are guaranteed that orangefs_clean_interrupted_operation(op)
doesn't return until nobody else can see op. Moreover, we don't need to play
with op refcounts anymore.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
... and clean the end of control device ->write_iter() while we are at it
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
new waiting-for-slot logics:
* make request for slot wait for bufmap to be set up if it
comes before it's installed *OR* while it's running down
* make closing control device wait for all slots to be freed
* waiting itself rewritten to (open-coded) analogues of wait_event_...
primitives - we would need wait_event_locked() and, pardon an obscenely
long name, wait_event_interruptible_exclusive_timeout_locked().
* we never wait for more than slot_timeout_secs in total and,
if during the wait the daemon goes away, we only allow
ORANGEFS_BUFMAP_WAIT_TIMEOUT_SECS for it to come back.
* (cosmetical) bitmap is used instead of an array of zeroes and ones
* old (and only reached if we are about to corrupt memory) waiting
for daemon restart in service_operation() removed.
[Martin's fixes folded]
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
... just hold the spinlock while fetching the field in question.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
* checking that daemon is running (to decide whether we want to limit
the timeout) should be done *after* the damn thing is included into
the list; doing that before means that if the daemon gets shut down
in between, we'll end up waiting indefinitely (== up to kill -9).
* cancels should go into the head of the queue - the sooner they
are picked, the less work daemon has to do and the sooner we get to
free the slot held by aborted operation.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Make cancels reuse the aborted read/write op, to make sure they do not
fail on lack of memory.
Don't issue a cancel unless the daemon has seen our read/write, has not
replied and isn't being shut down.
If cancel *is* issued, don't wait for it to complete; stash the slot
in there and just have it freed when cancel is finally replied to or
purged (and delay dropping the reference until then, obviously).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
it's always equal to __orangefs_bufmap and the latter can't change
until we are done
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
