linux-toradex.git/mm/truncate.c, branch v3.10.58

mm: drop vmtruncate

2012-12-20T23:46:29+00:00

Removed vmtruncate

Signed-off-by: Marco Stornelli 
Signed-off-by: Al Viro

mm: use clear_page_mlock() in page_remove_rmap()

2012-10-09T07:22:56+00:00

We had thought that pages could no longer get freed while still marked as
mlocked; but Johannes Weiner posted this program to demonstrate that
truncating an mlocked private file mapping containing COWed pages is still
mishandled:

#include 
#include 
#include 
#include 
#include 
#include 
#include 

int main(void)
{
	char *map;
	int fd;

	system("grep mlockfreed /proc/vmstat");
	fd = open("chigurh", O_CREAT|O_EXCL|O_RDWR);
	unlink("chigurh");
	ftruncate(fd, 4096);
	map = mmap(NULL, 4096, PROT_WRITE, MAP_PRIVATE, fd, 0);
	map[0] = 11;
	mlock(map, sizeof(fd));
	ftruncate(fd, 0);
	close(fd);
	munlock(map, sizeof(fd));
	munmap(map, 4096);
	system("grep mlockfreed /proc/vmstat");
	return 0;
}

The anon COWed pages are not caught by truncation's clear_page_mlock() of
the pagecache pages; but unmap_mapping_range() unmaps them, so we ought to
look out for them there in page_remove_rmap().  Indeed, why should
truncation or invalidation be doing the clear_page_mlock() when removing
from pagecache?  mlock is a property of mapping in userspace, not a
property of pagecache: an mlocked unmapped page is nonsensical.

Reported-by: Johannes Weiner 
Signed-off-by: Hugh Dickins 
Cc: Mel Gorman 
Cc: Rik van Riel 
Cc: Michel Lespinasse 
Cc: Ying Han 
Acked-by: Johannes Weiner 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: fix invalidate_complete_page2() lock ordering

2012-10-09T07:22:55+00:00

In fuzzing with trinity, lockdep protested "possible irq lock inversion
dependency detected" when isolate_lru_page() reenabled interrupts while
still holding the supposedly irq-safe tree_lock:

invalidate_inode_pages2
  invalidate_complete_page2
    spin_lock_irq(&mapping->tree_lock)
    clear_page_mlock
      isolate_lru_page
        spin_unlock_irq(&zone->lru_lock)

isolate_lru_page() is correct to enable interrupts unconditionally:
invalidate_complete_page2() is incorrect to call clear_page_mlock() while
holding tree_lock, which is supposed to nest inside lru_lock.

Both truncate_complete_page() and invalidate_complete_page() call
clear_page_mlock() before taking tree_lock to remove page from radix_tree.
 I guess invalidate_complete_page2() preferred to test PageDirty (again)
under tree_lock before committing to the munlock; but since the page has
already been unmapped, its state is already somewhat inconsistent, and no
worse if clear_page_mlock() moved up.

Reported-by: Sasha Levin 
Deciphered-by: Andrew Morton 
Signed-off-by: Hugh Dickins 
Acked-by: Mel Gorman 
Cc: Rik van Riel 
Cc: Johannes Weiner 
Cc: Michel Lespinasse 
Cc: Ying Han 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/fs: remove truncate_range

2012-05-29T23:22:23+00:00

Remove vmtruncate_range(), and remove the truncate_range method from
struct inode_operations: only tmpfs ever supported it, and tmpfs has now
converted over to using the fallocate method of file_operations.

Update Documentation accordingly, adding (setlease and) fallocate lines.
And while we're in mm.h, remove duplicate declarations of shmem_lock() and
shmem_file_setup(): everyone is now using the ones in shmem_fs.h.

Based-on-patch-by: Cong Wang 
Signed-off-by: Hugh Dickins 
Cc: Christoph Hellwig 
Cc: Cong Wang 
Cc: Al Viro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm for fs: add truncate_pagecache_range()

2012-03-29T00:14:35+00:00

Holepunching filesystems ext4 and xfs are using truncate_inode_pages_range
but forgetting to unmap pages first (ocfs2 remembers).  This is not really
a bug, since races already require truncate_inode_page() to handle that
case once the page is locked; but it can be very inefficient if the file
being punched happens to be mapped into many vmas.

Provide a drop-in replacement truncate_pagecache_range() which does the
unmapping pass first, handling the awkward mismatch between arguments to
truncate_inode_pages_range() and arguments to unmap_mapping_range().

Note that holepunching does not unmap privately COWed pages in the range:
POSIX requires that we do so when truncating, but it's hard to justify,
difficult to implement without an i_size cutoff, and no filesystem is
attempting to implement it.

Signed-off-by: Hugh Dickins 
Cc: "Theodore Ts'o" 
Cc: Andreas Dilger 
Cc: Mark Fasheh 
Cc: Joel Becker 
Cc: Ben Myers 
Cc: Alex Elder 
Cc: Christoph Hellwig 
Cc: Dave Chinner 
Cc: Al Viro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge tag 'stable/for-linus-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/mm

2012-03-23T02:52:47+00:00

Pull cleancache changes from Konrad Rzeszutek Wilk:
 "This has some patches for the cleancache API that should have been
  submitted a _long_ time ago.  They are basically cleanups:

   - rename of flush to invalidate

   - moving reporting of statistics into debugfs

   - use __read_mostly as necessary.

  Oh, and also the MAINTAINERS file change.  The files (except the
  MAINTAINERS file) have been in #linux-next for months now.  The late
  addition of MAINTAINERS file is a brain-fart on my side - didn't
  realize I needed that just until I was typing this up - and I based
  that patch on v3.3 - so the tree is on top of v3.3."

* tag 'stable/for-linus-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/mm:
  MAINTAINERS: Adding cleancache API to the list.
  mm: cleancache: Use __read_mostly as appropiate.
  mm: cleancache: report statistics via debugfs instead of sysfs.
  mm: zcache/tmem/cleancache: s/flush/invalidate/
  mm: cleancache: s/flush/invalidate/

mm: fix comment typo of truncate_inode_pages_range

2012-02-23T10:52:19+00:00

The typo of API truncate_inode_pages_range is not updated.

Signed-off-by: Liu Bo 
Signed-off-by: Jiri Kosina

mm: cleancache: s/flush/invalidate/

2012-01-23T21:06:24+00:00

Per akpm suggestions alter the use of the term flush to be
invalidate. The next patch will do this across all MM.

This change is completely cosmetic.

[v9: akpm@linux-foundation.org: change "flush" to "invalidate", part 3]

Signed-off-by: Dan Magenheimer 
Cc: Kamezawa Hiroyuki 
Cc: Jan Beulich 
Reviewed-by: Seth Jennings 
Cc: Jeremy Fitzhardinge 
Cc: Hugh Dickins 
Cc: Johannes Weiner 
Cc: Nitin Gupta 
Cc: Matthew Wilcox 
Cc: Chris Mason 
Cc: Rik Riel 
Cc: Andrew Morton 
[v10: Fixed  fs: move code out of buffer.c conflict change]
Signed-off-by: Konrad Rzeszutek Wilk

mm: Map most files to use export.h instead of module.h

2011-10-31T13:20:12+00:00

The files changed within are only using the EXPORT_SYMBOL
macro variants.  They are not using core modular infrastructure
and hence don't need module.h but only the export.h header.

Signed-off-by: Paul Gortmaker

mm: a few small updates for radix-swap

2011-08-04T00:25:24+00:00

Remove PageSwapBacked (!page_is_file_cache) cases from
add_to_page_cache_locked() and add_to_page_cache_lru(): those pages now
go through shmem_add_to_page_cache().

Remove a comment on maximum tmpfs size from fsstack_copy_inode_size(),
and add a comment on swap entries to invalidate_mapping_pages().

And mincore_page() uses find_get_page() on what might be shmem or a
tmpfs file: allow for a radix_tree_exceptional_entry(), and proceed to
find_get_page() on swapper_space if so (oh, swapper_space needs #ifdef).

Signed-off-by: Hugh Dickins 
Acked-by: Rik van Riel 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds