linux/fs/xfs/linux-2.6
Nick Piggin 54cb8821de mm: merge populate and nopage into fault (fixes nonlinear)
Nonlinear mappings are (AFAIKS) simply a virtual memory concept that encodes
the virtual address -> file offset differently from linear mappings.

->populate is a layering violation because the filesystem/pagecache code
should need to know anything about the virtual memory mapping.  The hitch here
is that the ->nopage handler didn't pass down enough information (ie.  pgoff).
 But it is more logical to pass pgoff rather than have the ->nopage function
calculate it itself anyway (because that's a similar layering violation).

Having the populate handler install the pte itself is likewise a nasty thing
to be doing.

This patch introduces a new fault handler that replaces ->nopage and
->populate and (later) ->nopfn.  Most of the old mechanism is still in place
so there is a lot of duplication and nice cleanups that can be removed if
everyone switches over.

The rationale for doing this in the first place is that nonlinear mappings are
subject to the pagefault vs invalidate/truncate race too, and it seemed stupid
to duplicate the synchronisation logic rather than just consolidate the two.

After this patch, MAP_NONBLOCK no longer sets up ptes for pages present in
pagecache.  Seems like a fringe functionality anyway.

NOPAGE_REFAULT is removed.  This should be implemented with ->fault, and no
users have hit mainline yet.

[akpm@linux-foundation.org: cleanup]
[randy.dunlap@oracle.com: doc. fixes for readahead]
[akpm@linux-foundation.org: build fix]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-19 10:04:41 -07:00
..
kmem.c
kmem.h [XFS] Use generic shrinker interfaces in XFS. 2007-07-14 15:23:53 +10:00
mrlock.h
mutex.h
sema.h
spin.h
sv.h
time.h
xfs_aops.c [XFS] Map unwritten extents correctly for I/o completion processing 2007-07-14 15:32:49 +10:00
xfs_aops.h
xfs_buf.c mm: clean up and kernelify shrinker registration 2007-07-17 10:23:00 -07:00
xfs_buf.h [XFS] Only use refcounted pages for I/O 2007-07-14 15:21:14 +10:00
xfs_cred.h
xfs_dmapi_priv.h
xfs_export.c
xfs_export.h
xfs_file.c mm: merge populate and nopage into fault (fixes nonlinear) 2007-07-19 10:04:41 -07:00
xfs_fs_subr.c
xfs_fs_subr.h
xfs_globals.c [XFS] Concurrent Multi-File Data Streams 2007-07-14 15:40:53 +10:00
xfs_globals.h
xfs_ioctl32.c [XFS] Fix XFS_IOC_FSBULKSTAT{,_SINGLE} & XFS_IOC_FSINUMBERS in compat mode 2007-07-14 15:42:50 +10:00
xfs_ioctl32.h
xfs_ioctl.c [XFS] Fix XFS_IOC_FSBULKSTAT{,_SINGLE} & XFS_IOC_FSINUMBERS in compat mode 2007-07-14 15:42:50 +10:00
xfs_iops.c
xfs_iops.h
xfs_linux.h [XFS] Concurrent Multi-File Data Streams 2007-07-14 15:40:53 +10:00
xfs_lrw.c sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
xfs_lrw.h sendfile: remove .sendfile from filesystems that use generic_file_sendfile() 2007-07-10 08:04:13 +02:00
xfs_stats.c
xfs_stats.h
xfs_super.c Freezer: make kernel threads nonfreezable by default 2007-07-17 10:23:02 -07:00
xfs_super.h knfsd: exportfs: add exportfs.h header 2007-07-17 10:23:06 -07:00
xfs_sysctl.c [XFS] Concurrent Multi-File Data Streams 2007-07-14 15:40:53 +10:00
xfs_sysctl.h [XFS] Concurrent Multi-File Data Streams 2007-07-14 15:40:53 +10:00
xfs_version.h
xfs_vfs.c
xfs_vfs.h [XFS] Fix remount,readonly path to flush everything correctly. 2007-07-14 15:35:58 +10:00
xfs_vnode.c
xfs_vnode.h [XFS] XFS should not be looking at filp reference counts 2007-07-14 15:37:37 +10:00