Erez Zadok [Fri, 13 May 2022 23:43:54 +0000 (19:43 -0400)]
Wrapfs: add ->bmap support
Signed-off-by: Aditya Sonavane <aditya.sonavane@stonybrook.edu>
Signed-off-by: Erez Zadok <ezk@cs.stonybrook.edu>
Erez Zadok [Sat, 7 May 2022 22:12:18 +0000 (18:12 -0400)]
wrapfs: copyright year update
Erez Zadok [Sat, 7 May 2022 20:48:17 +0000 (16:48 -0400)]
wrapfs: change http URLs to https
Erez Zadok [Mon, 16 Dec 2019 00:00:55 +0000 (19:00 -0500)]
merge changes
Erez Zadok [Sat, 14 Dec 2019 05:06:03 +0000 (00:06 -0500)]
wrapfs: update copyright
Erez Zadok [Sat, 14 Dec 2019 04:21:23 +0000 (23:21 -0500)]
wrapfs: remove unused variable
Erez Zadok [Fri, 29 Mar 2019 20:45:52 +0000 (16:45 -0400)]
update copyright
Erez Zadok [Fri, 29 Mar 2019 20:39:45 +0000 (16:39 -0400)]
fix spell error
Erez Zadok [Sun, 19 Feb 2017 00:11:23 +0000 (19:11 -0500)]
Wrapfs: ->iget fixes
Change where we igrab/iput to ensure we always hold a valid lower_inode.
Return ENOMEM (not EACCES) if iget5_locked returns NULL.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Sat, 18 Feb 2017 20:27:39 +0000 (15:27 -0500)]
Wrapfs: update copyrights for 2017
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Sun, 22 May 2016 04:41:20 +0000 (00:41 -0400)]
Wrapfs: support NFS exports
Based on patch from Sandeep Joshi <sanjos100@gmail.com>.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Sun, 22 May 2016 04:41:20 +0000 (00:41 -0400)]
Wrapfs: use d_splice_alias
Refactor interpose code to allow lookup to use d_splice_alias.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 4 Nov 2015 04:35:30 +0000 (23:35 -0500)]
Wrapfs: update copyright year to 2015
Erez Zadok [Wed, 4 Nov 2015 04:35:30 +0000 (23:35 -0500)]
Wrapfs: use vfs xattr helpers
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Sat, 16 Aug 2014 02:56:54 +0000 (22:56 -0400)]
Wrapfs: properly copy meta-data after AIO operations from lower inode
Signed-off-by: Mengyang Li <li.mengyang@stonybrook.edu>
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Mon, 11 Aug 2014 22:30:05 +0000 (18:30 -0400)]
Wrapfs: leave placeholders for updating upper inode after AIO
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Sun, 10 Aug 2014 04:59:12 +0000 (00:59 -0400)]
Wrapfs: protect lower_file by ref-count during aio operation
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Signed-off-by: Mengyang Li <li.mengyang@stonybrook.edu>
Erez Zadok [Thu, 26 Jun 2014 02:40:51 +0000 (22:40 -0400)]
Wrapfs: fix ->llseek to update upper and lower offsets
Fixes bug: xfstests generic/257. f_pos consistently is required by and
only by dir_ops->wrapfs_readdir, main_ops is not affected.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Signed-off-by: Mengyang Li <li.mengyang@stonybrook.edu>
Erez Zadok [Thu, 26 Jun 2014 02:40:51 +0000 (22:40 -0400)]
Wrapfs: support extended attributes (xattr) operations
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Signed-off-by: Mengyang Li <li.mengyang@stonybrook.edu>
Erez Zadok [Sat, 21 Jun 2014 00:03:07 +0000 (20:03 -0400)]
Wrapfs: support asynchronous-IO (AIO) operations
Signed-off-by: Li Mengyang <li.mengyang@stonybrook.edu>
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Sat, 21 Jun 2014 00:03:07 +0000 (20:03 -0400)]
Wrapfs: support direct-IO (DIO) operations
Signed-off-by: Li Mengyang <li.mengyang@stonybrook.edu>
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Thu, 15 May 2014 04:16:03 +0000 (00:16 -0400)]
Wrapfs: implement vm_ops->page_mkwrite
Some file systems (e.g., ext4) require it. Reported by Ted Ts'o.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Thu, 3 Apr 2014 17:24:28 +0000 (13:24 -0400)]
Wrapfs: update documentation
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Thu, 3 Apr 2014 17:17:55 +0000 (13:17 -0400)]
Wrapfs: update maintainers
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 21 Jan 2014 08:03:00 +0000 (03:03 -0500)]
Wrapfs: update documentation
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 21 Jan 2014 06:25:54 +0000 (01:25 -0500)]
Wrapfs: 2014 Copyright update
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 27 Nov 2013 04:05:22 +0000 (23:05 -0500)]
Wrapfs: use generic put_link helper
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 27 Nov 2013 04:03:46 +0000 (23:03 -0500)]
Wrapfs: remove unnecessary initializations
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Sun, 24 Nov 2013 16:12:07 +0000 (11:12 -0500)]
Wrapfs: remove deprecated init_lower_nd
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 20 Nov 2013 00:00:00 +0000 (19:00 -0500)]
Wrapfs: update MAINTAINERS info
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 19 Nov 2013 23:59:47 +0000 (18:59 -0500)]
patch wrapfs-copyright-update.patch
Erez Zadok [Tue, 19 Nov 2013 22:23:31 +0000 (17:23 -0500)]
Wrapfs: use DCACHE_OP_REVALIDATE flag in ->d_revalidate
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 19 Nov 2013 22:22:31 +0000 (17:22 -0500)]
Wrapfs: implement ->getattr
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 19 Nov 2013 22:21:31 +0000 (17:21 -0500)]
Wrapfs: use file_inode helper
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 19 Nov 2013 22:20:31 +0000 (17:20 -0500)]
Wrapfs: call filemap_write_and_wait in ->flush
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 19 Nov 2013 22:19:31 +0000 (17:19 -0500)]
Wrapfs: handle new VFS API with delegation support
For now, wrapfs isn't supporting NFS delegations.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 19 Nov 2013 22:18:31 +0000 (17:18 -0500)]
VFS: export vfs_path_lookup
In 3.12, this useful function was unexported: wrapfs needs a way to lookup
relative to a struct path and use a proper vfsmount, unlike lookup_one_len.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 19 Nov 2013 22:17:31 +0000 (17:17 -0500)]
Wrapfs: ->readdir op now ->iterate
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 05:36:58 +0000 (01:36 -0400)]
Wrapfs: copy lower inode attributes in ->ioctl
Some ioctls (e.g., EXT2_IOC_SETFLAGS) can change inode attributes, so copy
them from lower inode.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 05:36:58 +0000 (01:36 -0400)]
Wrapfs: remove unnecessary call to vm_unmap in ->mmap
Code is unnecessary and causes deadlocks in newer kernels.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 03:19:32 +0000 (23:19 -0400)]
Wrapfs: declare MODULE_ALIAS_FS
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 03:19:32 +0000 (23:19 -0400)]
Wrapfs: don't use FS_REVAL_DOT in fs_flags
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 03:19:31 +0000 (23:19 -0400)]
Wrapfs: remove dependency on now-defunct CONFIG_EXPERIMENTAL
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 03:19:31 +0000 (23:19 -0400)]
Wrapfs: dentry_open() no longer does mntput/dput
We need to grab a reference on the path before dentry_open, and drop it
after.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 03:19:30 +0000 (23:19 -0400)]
Wrapfs: no need to call mnt_want_write any longer
Apparently this is now being done by the VFS.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 03:19:30 +0000 (23:19 -0400)]
Wrapfs: remove VM_CAN_NONLINEAR flag use in ->mmap
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 03:19:29 +0000 (23:19 -0400)]
Wrapfs: ->lookup takes flags not a nameidata
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 03:19:29 +0000 (23:19 -0400)]
Wrapfs: ->create no longer takes a nameidata, only a flag
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 03:19:29 +0000 (23:19 -0400)]
Wrapfs: ->d_revalidate now takes namei flags, not nameidata
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 03:19:28 +0000 (23:19 -0400)]
Wrapfs: struct nameidata no longer has an open-intent data
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 03:19:28 +0000 (23:19 -0400)]
Wrapfs: dentry_open now takes a struct path
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 03:19:27 +0000 (23:19 -0400)]
Wrapfs: use vm_munmap in ->mmap
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 03:19:27 +0000 (23:19 -0400)]
Wrapfs: use clear_inode in evict_inode
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 5 Jun 2013 03:19:26 +0000 (23:19 -0400)]
Wrapfs: use d_make_root
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 31 Jan 2012 09:40:19 +0000 (04:40 -0500)]
Wrapfs: use mode_t
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Mon, 30 Jan 2012 01:34:27 +0000 (20:34 -0500)]
Wrapfs: use set_nlink()
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Fri, 9 Sep 2011 04:47:49 +0000 (00:47 -0400)]
Wrapfs: drop our dentry in ->rmdir
Also clear nlinks on our inode.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 6 Sep 2011 04:10:32 +0000 (00:10 -0400)]
Wrapfs: use d_alloc_root
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 6 Sep 2011 04:10:31 +0000 (00:10 -0400)]
Wrapfs: use d_set_d_op
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 6 Sep 2011 04:10:30 +0000 (00:10 -0400)]
Wrapfs: use updated vfs_path_lookup prototype
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 6 Sep 2011 04:10:30 +0000 (00:10 -0400)]
Wrapfs: ->fsync updates for new prototype
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 6 Sep 2011 04:10:29 +0000 (00:10 -0400)]
Wrapfs: support LOOKUP_RCU in ->d_revalidate
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 6 Sep 2011 04:10:28 +0000 (00:10 -0400)]
Wrapfs: new ->permission prototype and fixes.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Mon, 2 May 2011 06:00:02 +0000 (02:00 -0400)]
Wrapfs: lookup fixes
Don't use lookup_one_len any longer (doesn't work for NFS).
Initialize lower wrapfs_dentry_info so lower_path is NULL.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Fri, 18 Mar 2011 17:14:28 +0000 (13:14 -0400)]
Wrapfs: remove extra debug in rmdir
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Fri, 18 Mar 2011 16:38:01 +0000 (12:38 -0400)]
Wrapfs: checkpatch fixes
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Fri, 18 Mar 2011 04:45:17 +0000 (00:45 -0400)]
Wrapfs: port to 2.6.39
Remove lock/unlock_kernel in ->fasync.
Convert from ->get_sb to ->mount op.
Remove include to smp_lock.h, added sched.h.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Fri, 18 Mar 2011 03:21:55 +0000 (23:21 -0400)]
Wrapfs: copyright update for 2011
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Fri, 18 Mar 2011 03:21:55 +0000 (23:21 -0400)]
Wrapfs: better handling of NFS silly-renamed files
In ->unlink, if we try to unlink an NFS silly-renamed file, NFS returns
-EBUSY. We have to treat it as a success and return 0 to the VFS. NFS will
remove silly-deleted files later on anyway.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Fri, 18 Mar 2011 03:21:55 +0000 (23:21 -0400)]
Wrapfs: update parent directory inode size in inode ops
After ->unlink, ->rmdir, and ->rename, we need to copy the (possibly
changed) inode size of the parent directory(ies) where the operation took
place.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Fri, 18 Mar 2011 03:21:55 +0000 (23:21 -0400)]
Wrapfs: remove unnecessary calls to copy lower inode->n_links
Removed from ->create, ->symlink, and ->mknod.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 8 Mar 2011 04:20:33 +0000 (23:20 -0500)]
Wrapfs: ->setattr fixes
Call inode_change_ok on our inode, not lower.
Don't copy inode sizes (VFS does it).
Pass lower file in struct iattr passed to notify_change on lower inode.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Sun, 6 Mar 2011 21:23:16 +0000 (16:23 -0500)]
Wrapfs: update ->permission prototye and code for new iperm flag
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Fri, 12 Nov 2010 23:15:05 +0000 (18:15 -0500)]
Wrapfs: handle maxbytes properly
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Sat, 11 Sep 2010 19:49:33 +0000 (15:49 -0400)]
Wrapfs: support ->unlocked_ioctl and ->compat_ioctl
Old ->ioctl was split into ->unlocked_ioctl and ->compat_ioctl. Compat
version doesn't need to lock_kernel any longer.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 11 Aug 2010 03:50:14 +0000 (23:50 -0400)]
Wrapfs: new vfs_statfs and ->evict_inode prototypes
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Sat, 7 Aug 2010 03:37:29 +0000 (23:37 -0400)]
Wrapfs: update ->fsync prototype
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Wed, 21 Apr 2010 01:22:02 +0000 (21:22 -0400)]
Wrapfs: update documentation
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 20 Apr 2010 19:32:09 +0000 (15:32 -0400)]
Wrapfs: include slab.h
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 20 Apr 2010 19:26:02 +0000 (15:26 -0400)]
Wrapfs: avoid an extra path_get/put pair in wrapfs_open
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Fri, 26 Feb 2010 08:18:04 +0000 (03:18 -0500)]
Wrapfs: decrement nd_path on follow_link error
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 09:27:00 +0000 (04:27 -0500)]
Wrapfs: don't mention kernel version in modload message
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Kconfig: hook to configure Wrapfs
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Makefile: hook to compile Wrapfs
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Wrapfs: file system magic number
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Wrapfs: Kconfig options
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Wrapfs: main Makefile
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Wrapfs: vm_ops operations
Includes necessary address_space workaround ops.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Wrapfs: mount-time and module-linkage functions
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Wrapfs: lookup-related functions
Main lookup function, nameidata helpers, and stacking-interposition
functions.
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Wrapfs: file operations
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Wrapfs: dentry operations
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Wrapfs: inode operations
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Wrapfs: superblock operations
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Wrapfs: main header file
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Wrapfs: Maintainers
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Documentation: index entry for Wrapfs
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Erez Zadok [Tue, 5 Jan 2010 01:45:06 +0000 (20:45 -0500)]
Wrapfs: introduction and usage documentation
Signed-off-by: Erez Zadok <ezk@cs.sunysb.edu>
Greg Kroah-Hartman [Sun, 11 Sep 2016 08:00:18 +0000 (10:00 +0200)]
Linux 3.14.79
Andrea Arcangeli [Fri, 26 Feb 2016 23:19:28 +0000 (15:19 -0800)]
mm: thp: fix SMP race condition between THP page fault and MADV_DONTNEED
commit
ad33bb04b2a6cee6c1f99fabb15cddbf93ff0433 upstream.
pmd_trans_unstable()/pmd_none_or_trans_huge_or_clear_bad() were
introduced to locklessy (but atomically) detect when a pmd is a regular
(stable) pmd or when the pmd is unstable and can infinitely transition
from pmd_none() and pmd_trans_huge() from under us, while only holding
the mmap_sem for reading (for writing not).
While holding the mmap_sem only for reading, MADV_DONTNEED can run from
under us and so before we can assume the pmd to be a regular stable pmd
we need to compare it against pmd_none() and pmd_trans_huge() in an
atomic way, with pmd_trans_unstable(). The old pmd_trans_huge() left a
tiny window for a race.
Useful applications are unlikely to notice the difference as doing
MADV_DONTNEED concurrently with a page fault would lead to undefined
behavior.
[js] 3.12 backport: no pmd_devmap in 3.12 yet.
[akpm@linux-foundation.org: tidy up comment grammar/layout]
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
projects / wrapfs-3.14.y.git / log