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  1. 13 12月, 2016 3 次提交
  3. 28 9月, 2016 2 次提交
  5. 24 6月, 2016 3 次提交
  7. 15 1月, 2016 1 次提交
    • V
      kmemcg: account certain kmem allocations to memcg · 5d097056
      由 Vladimir Davydov 提交于 
      Mark those kmem allocations that are known to be easily triggered from
userspace as __GFP_ACCOUNT/SLAB_ACCOUNT, which makes them accounted to
memcg.  For the list, see below:

 - threadinfo
 - task_struct
 - task_delay_info
 - pid
 - cred
 - mm_struct
 - vm_area_struct and vm_region (nommu)
 - anon_vma and anon_vma_chain
 - signal_struct
 - sighand_struct
 - fs_struct
 - files_struct
 - fdtable and fdtable->full_fds_bits
 - dentry and external_name
 - inode for all filesystems. This is the most tedious part, because
   most filesystems overwrite the alloc_inode method.

The list is far from complete, so feel free to add more objects.
Nevertheless, it should be close to "account everything" approach and
keep most workloads within bounds.  Malevolent users will be able to
breach the limit, but this was possible even with the former "account
everything" approach (simply because it did not account everything in
fact).

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NVladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Acked-by: NMichal Hocko <mhocko@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Greg Thelen <gthelen@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      5d097056
  9. 31 12月, 2015 1 次提交
  11. 09 12月, 2015 1 次提交
    • A
      replace ->follow_link() with new method that could stay in RCU mode · 6b255391
      由 Al Viro 提交于 
      new method: ->get_link(); replacement of ->follow_link().  The differences
are:
	* inode and dentry are passed separately
	* might be called both in RCU and non-RCU mode;
the former is indicated by passing it a NULL dentry.
	* when called that way it isn't allowed to block
and should return ERR_PTR(-ECHILD) if it needs to be called
in non-RCU mode.

It's a flagday change - the old method is gone, all in-tree instances
converted.  Conversion isn't hard; said that, so far very few instances
do not immediately bail out when called in RCU mode.  That'll change
in the next commits.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      6b255391
  13. 01 7月, 2015 1 次提交
  15. 11 5月, 2015 3 次提交
    • A
      switch ->put_link() from dentry to inode · 5f2c4179
      由 Al Viro 提交于 
      only one instance looks at that argument at all; that sole
exception wants inode rather than dentry.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      5f2c4179
    • A
      don't pass nameidata to ->follow_link() · 6e77137b
      由 Al Viro 提交于 
      its only use is getting passed to nd_jump_link(), which can obtain
it from current->nameidata
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      6e77137b
    • A
      new ->follow_link() and ->put_link() calling conventions · 680baacb
      由 Al Viro 提交于 
      a) instead of storing the symlink body (via nd_set_link()) and returning
an opaque pointer later passed to ->put_link(), ->follow_link() _stores_
that opaque pointer (into void * passed by address by caller) and returns
the symlink body.  Returning ERR_PTR() on error, NULL on jump (procfs magic
symlinks) and pointer to symlink body for normal symlinks.  Stored pointer
is ignored in all cases except the last one.

Storing NULL for opaque pointer (or not storing it at all) means no call
of ->put_link().

b) the body used to be passed to ->put_link() implicitly (via nameidata).
Now only the opaque pointer is.  In the cases when we used the symlink body
to free stuff, ->follow_link() now should store it as opaque pointer in addition
to returning it.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      680baacb
  17. 16 4月, 2015 1 次提交
  19. 23 2月, 2015 1 次提交
  21. 13 2月, 2015 1 次提交
  23. 11 12月, 2014 2 次提交
    • A
      kill proc_ns completely · 3d3d35b1
      由 Al Viro 提交于 
      procfs inodes need only the ns_ops part; nsfs inodes don't need it at all
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      3d3d35b1
    • A
      take the targets of /proc/*/ns/* symlinks to separate fs · e149ed2b
      由 Al Viro 提交于 
      New pseudo-filesystem: nsfs.  Targets of /proc/*/ns/* live there now.
It's not mountable (not even registered, so it's not in /proc/filesystems,
etc.).  Files on it *are* bindable - we explicitly permit that in do_loopback().

This stuff lives in fs/nsfs.c now; proc_ns_fget() moved there as well.
get_proc_ns() is a macro now (it's simply returning ->i_private; would
have been an inline, if not for header ordering headache).
proc_ns_inode() is an ex-parrot.  The interface used in procfs is
ns_get_path(path, task, ops) and ns_get_name(buf, size, task, ops).

Dentries and inodes are never hashed; a non-counting reference to dentry
is stashed in ns_common (removed by ->d_prune()) and reused by ns_get_path()
if present.  See ns_get_path()/ns_prune_dentry/nsfs_evict() for details
of that mechanism.

As the result, proc_ns_follow_link() has stopped poking in nd->path.mnt;
it does nd_jump_link() on a consistent <vfsmount,dentry> pair it gets
from ns_get_path().
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      e149ed2b
  25. 05 12月, 2014 2 次提交
  27. 05 8月, 2014 1 次提交
    • E
      proc: Implement /proc/thread-self to point at the directory of the current thread · 0097875b
      由 Eric W. Biederman 提交于 
      /proc/thread-self is derived from /proc/self.  /proc/thread-self
points to the directory in proc containing information about the
current thread.

This funtionality has been missing for a long time, and is tricky to
implement in userspace as gettid() is not exported by glibc.  More
importantly this allows fixing defects in /proc/mounts and /proc/net
where in a threaded application today they wind up being empty files
when only the initial pthread has exited, causing problems for other
threads.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
      0097875b
  29. 08 4月, 2014 1 次提交
  31. 04 4月, 2014 1 次提交
    • J
      mm + fs: store shadow entries in page cache · 91b0abe3
      由 Johannes Weiner 提交于 
      Reclaim will be leaving shadow entries in the page cache radix tree upon
evicting the real page.  As those pages are found from the LRU, an
iput() can lead to the inode being freed concurrently.  At this point,
reclaim must no longer install shadow pages because the inode freeing
code needs to ensure the page tree is really empty.

Add an address_space flag, AS_EXITING, that the inode freeing code sets
under the tree lock before doing the final truncate.  Reclaim will check
for this flag before installing shadow pages.
Signed-off-by: NJohannes Weiner <hannes@cmpxchg.org>
Reviewed-by: NRik van Riel <riel@redhat.com>
Reviewed-by: NMinchan Kim <minchan@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Bob Liu <bob.liu@oracle.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jan Kara <jack@suse.cz>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Luigi Semenzato <semenzato@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Metin Doslu <metin@citusdata.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Ozgun Erdogan <ozgun@citusdata.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Roman Gushchin <klamm@yandex-team.ru>
Cc: Ryan Mallon <rmallon@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      91b0abe3
  33. 13 12月, 2013 1 次提交
    • J
      procfs: also fix proc_reg_get_unmapped_area() for !MMU case · ae5758a1
      由 Jan Beulich 提交于 
      Commit fad1a86e ("procfs: call default get_unmapped_area on
MMU-present architectures"), as its title says, took care of only the
MMU case, leaving the !MMU side still in the regressed state (returning
-EIO in all cases where pde->proc_fops->get_unmapped_area is NULL).

From the fad1a86e changelog:

 "Commit c4fe2448 ("sparc: fix PCI device proc file mmap(2)") added
  proc_reg_get_unmapped_area in proc_reg_file_ops and
  proc_reg_file_ops_no_compat, by which now mmap always returns EIO if
  get_unmapped_area method is not defined for the target procfs file, which
  causes regression of mmap on /proc/vmcore.

  To address this issue, like get_unmapped_area(), call default
  current->mm->get_unmapped_area on MMU-present architectures if
  pde->proc_fops->get_unmapped_area, i.e.  the one in actual file operation
  in the procfs file, is not defined"
Signed-off-by: NJan Beulich <jbeulich@suse.com>
Cc: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: <stable@vger.kernel.org>	[3.12.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      ae5758a1
  35. 13 11月, 2013 1 次提交
  37. 17 10月, 2013 2 次提交
  39. 06 9月, 2013 1 次提交
  41. 02 5月, 2013 1 次提交
  43. 30 4月, 2013 2 次提交
  45. 10 4月, 2013 5 次提交
  47. 23 3月, 2013 1 次提交
    • L
      vfs,proc: guarantee unique inodes in /proc · 51f0885e
      由 Linus Torvalds 提交于 
      Dave Jones found another /proc issue with his Trinity tool: thanks to
the namespace model, we can have multiple /proc dentries that point to
the same inode, aliasing directories in /proc/<pid>/net/ for example.

This ends up being a total disaster, because it acts like hardlinked
directories, and causes locking problems.  We rely on the topological
sort of the inodes pointed to by dentries, and if we have aliased
directories, that odering becomes unreliable.

In short: don't do this.  Multiple dentries with the same (directory)
inode is just a bad idea, and the namespace code should never have
exposed things this way.  But we're kind of stuck with it.

This solves things by just always allocating a new inode during /proc
dentry lookup, instead of using "iget_locked()" to look up existing
inodes by superblock and number.  That actually simplies the code a bit,
at the cost of potentially doing more inode [de]allocations.

That said, the inode lookup wasn't free either (and did a lot of locking
of inodes), so it is probably not that noticeable.  We could easily keep
the old lookup model for non-directory entries, but rather than try to
be excessively clever this just implements the minimal and simplest
workaround for the problem.
Reported-and-tested-by: NDave Jones <davej@redhat.com>
Analyzed-by: NAl Viro <viro@zeniv.linux.org.uk>
Cc: stable@vger.kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      51f0885e
  49. 28 2月, 2013 1 次提交