kernel.git/mm/truncate.c, branch linux-3.11.y

mm: teach truncate_inode_pages_range() to handle non page aligned ranges

2013-05-28T03:32:35Z

This commit changes truncate_inode_pages_range() so it can handle non page aligned regions of the truncate. Currently we can hit BUG_ON when the end of the range is not page aligned, but we can handle unaligned start of the range. Being able to handle non page aligned regions of the page can help file system punch_hole implementations and save some work, because once we're holding the page we might as well deal with it right away. In previous commits we've changed ->invalidatepage() prototype to accept 'length' argument to be able to specify range to invalidate. No we can use that new ability in truncate_inode_pages_range(). Signed-off-by: Lukas Czerner Cc: Andrew Morton Cc: Hugh Dickins Signed-off-by: Theodore Ts'o

mm: change invalidatepage prototype to accept length

2013-05-22T03:17:23Z

Currently there is no way to truncate partial page where the end truncate point is not at the end of the page. This is because it was not needed and the functionality was enough for file system truncate operation to work properly. However more file systems now support punch hole feature and it can benefit from mm supporting truncating page just up to the certain point. Specifically, with this functionality truncate_inode_pages_range() can be changed so it supports truncating partial page at the end of the range (currently it will BUG_ON() if 'end' is not at the end of the page). This commit changes the invalidatepage() address space operation prototype to accept range to be invalidated and update all the instances for it. We also change the block_invalidatepage() in the same way and actually make a use of the new length argument implementing range invalidation. Actual file system implementations will follow except the file systems where the changes are really simple and should not change the behaviour in any way .Implementation for truncate_page_range() which will be able to accept page unaligned ranges will follow as well. Signed-off-by: Lukas Czerner Cc: Andrew Morton Cc: Hugh Dickins

mm: drop vmtruncate

2012-12-20T23:46:29Z

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

mm: use clear_page_mlock() in page_remove_rmap()

2012-10-09T07:22:56Z

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

2012-10-09T07:22:55Z

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

2012-05-29T23:22:23Z

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()

2012-03-29T00:14:35Z

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

2012-03-23T02:52:47Z

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

2012-02-23T10:52:19Z

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/

2012-01-23T21:06:24Z

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