linux-stable.git/fs/proc/inode.c, branch linux-3.16.y

proc: Allow creating permanently empty directories that serve as mount points

2015-07-15T09:01:06+00:00

commit eb6d38d5427b3ad42f5268da0f1dd31bb0af1264 upstream.

Add a new function proc_create_mount_point that when used to creates a
directory that can not be added to.

Add a new function is_empty_pde to test if a function is a mount
point.

Update the code to use make_empty_dir_inode when reporting
a permanently empty directory to the vfs.

Update the code to not allow adding to permanently empty directories.

Update /proc/openprom and /proc/fs/nfsd to be permanently empty directories.

Signed-off-by: "Eric W. Biederman" 
[ luis: backported to 3.16: adjusted context ]
Signed-off-by: Luis Henriques

procfs: fix race between symlink removals and traversals

2015-03-02T15:04:37+00:00

commit 7e0e953bb0cf649f93277ac8fb67ecbb7f7b04a9 upstream.

use_pde()/unuse_pde() in ->follow_link()/->put_link() resp.

Signed-off-by: Al Viro 
Signed-off-by: Luis Henriques

fs/proc/inode.c: use RCU_INIT_POINTER(x, NULL)

2014-04-07T23:36:04+00:00

Replace rcu_assign_pointer(x, NULL) with RCU_INIT_POINTER(x, NULL)

The rcu_assign_pointer() ensures that the initialization of a structure
is carried out before storing a pointer to that structure.  And in the
case of the NULL pointer, there is no structure to initialize.  So,
rcu_assign_pointer(p, NULL) can be safely converted to
RCU_INIT_POINTER(p, NULL)

Signed-off-by: Monam Agarwal 
Cc: "Paul E. McKenney" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm + fs: store shadow entries in page cache

2014-04-03T23:21:01+00:00

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: Johannes Weiner 
Reviewed-by: Rik van Riel 
Reviewed-by: Minchan Kim 
Cc: Andrea Arcangeli 
Cc: Bob Liu 
Cc: Christoph Hellwig 
Cc: Dave Chinner 
Cc: Greg Thelen 
Cc: Hugh Dickins 
Cc: Jan Kara 
Cc: KOSAKI Motohiro 
Cc: Luigi Semenzato 
Cc: Mel Gorman 
Cc: Metin Doslu 
Cc: Michel Lespinasse 
Cc: Ozgun Erdogan 
Cc: Peter Zijlstra 
Cc: Roman Gushchin 
Cc: Ryan Mallon 
Cc: Tejun Heo 
Cc: Vlastimil Babka 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

procfs: also fix proc_reg_get_unmapped_area() for !MMU case

2013-12-13T02:19:26+00:00

Commit fad1a86e25e0 ("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 fad1a86e25e0 changelog:

 "Commit c4fe24485729 ("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: Jan Beulich 
Cc: HATAYAMA Daisuke 
Cc: Alexey Dobriyan 
Cc: David S. Miller 
Cc: 	[3.12.x]
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

procfs: clean up proc_reg_get_unmapped_area for 80-column limit

2013-11-13T03:09:33+00:00

Clean up proc_reg_get_unmapped_area due to its 80-column limit
violation.

Signed-off-by: HATAYAMA Daisuke 
Tested-by: Michael Holzheu 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

procfs: call default get_unmapped_area on MMU-present architectures

2013-10-17T04:35:53+00:00

Commit c4fe24485729 ("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.

Reported-by: Michael Holzheu 
Signed-off-by: HATAYAMA Daisuke 
Cc: Alexey Dobriyan 
Cc: David S. Miller 
Tested-by: Michael Holzheu 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

procfs: fix unintended truncation of returned mapped address

2013-10-17T04:35:53+00:00

Currently, proc_reg_get_unmapped_area truncates upper 32-bit of the
mapped virtual address returned from get_unmapped_area method in
pde->proc_fops due to the variable rv of signed integer on x86_64.  This
is too small to have vitual address of unsigned long on x86_64 since on
x86_64, signed integer is of 4 bytes while unsigned long is of 8 bytes.
To fix this issue, use unsigned long instead.

Fixes a regression added in commit c4fe24485729 ("sparc: fix PCI device
proc file mmap(2)").

Signed-off-by: HATAYAMA Daisuke 
Cc: Alexey Dobriyan 
Cc: David S. Miller 
Tested-by: Michael Holzheu 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

sparc: fix PCI device proc file mmap(2)

2013-09-05T19:12:51+00:00

Commit 786d7e1612f0b0adb6046f19b906609e4fe8b1ba "Fix rmmod/read/write races in /proc entries"
must have broken mmapping of PCI device proc files on Sparc.

Notice how it adds wrapper around ->mmap but doesn't do it around ->get_unmapped_area.
Add wrapper around ->get_unmapped_area.

Signed-off-by: Alexey Dobriyan 
Signed-off-by: David S. Miller

proc: Split the namespace stuff out into linux/proc_ns.h

2013-05-01T21:29:39+00:00

Split the proc namespace stuff out into linux/proc_ns.h.

Signed-off-by: David Howells 
cc: netdev@vger.kernel.org
cc: Serge E. Hallyn 
cc: Eric W. Biederman 
Signed-off-by: Al Viro