linux-toradex.git/include/linux/iomap.h, branch v5.0-rc3

fs/iomap.c: change return type to vm_fault_t

2018-10-26T23:25:18+00:00

Change iomap_page_mkwrite() return type to vm_fault_t.

see commit 1c8f422059ae ("mm: change return type to vm_fault_t") for
reference.

Link: http://lkml.kernel.org/r/20180827172050.GA18673@jordon-HP-15-Notebook-PC
Signed-off-by: Souptick Joarder 
Reviewed-by: Matthew Wilcox 
Cc: Matthew Wilcox 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

iomap: add support for sub-pagesize buffered I/O without buffer heads

2018-07-12T05:26:05+00:00

After already supporting a simple implementation of buffered writes for
the blocksize == PAGE_SIZE case in the last commit this adds full support
even for smaller block sizes.   There are three bits of per-block
information in the buffer_head structure that really matter for the iomap
read and write path:

 - uptodate status (BH_uptodate)
 - marked as currently under read I/O (BH_Async_Read)
 - marked as currently under write I/O (BH_Async_Write)

Instead of having new per-block structures this now adds a per-page
structure called struct iomap_page to track this information in a slightly
different form:

 - a bitmap for the per-block uptodate status.  For worst case of a 64k
   page size system this bitmap needs to contain 128 bits.  For the
   typical 4k page size case it only needs 8 bits, although we still
   need a full unsigned long due to the way the atomic bitmap API works.
 - two atomic_t counters are used to track the outstanding read and write
   counts

There is quite a bit of boilerplate code as the buffered I/O path uses
various helper methods, but the actual code is very straight forward.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Brian Foster 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong

iomap: add initial support for writes without buffer heads

2018-06-20T16:32:41+00:00

For now just limited to blocksize == PAGE_SIZE, where we can simply read
in the full page in write begin, and just set the whole page dirty after
copying data into it.  This code is enabled by default and XFS will now
be feed pages without buffer heads in ->writepage and ->writepages.

If a file system sets the IOMAP_F_BUFFER_HEAD flag on the iomap the old
path will still be used, this both helps the transition in XFS and
prepares for the gfs2 migration to the iomap infrastructure.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Brian Foster 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong

iomap: add an iomap-based readpage and readpages implementation

2018-06-19T22:10:57+00:00

Simply use iomap_apply to iterate over the file and a submit a bio for
each non-uptodate but mapped region and zero everything else.  Note that
as-is this can not be used for file systems with a blocksize smaller than
the page size, but that support will be added later.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong

iomap: add private pointer to struct iomap

2018-06-19T22:10:57+00:00

Add a private pointer to struct iomap to allow filesystems to pass data
from iomap_begin to iomap_end.  Will be used by gfs2 for passing on the
on-disk inode buffer head.

Signed-off-by: Andreas Gruenbacher 
Signed-off-by: Christoph Hellwig 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong

iomap: add a page_done callback

2018-06-19T22:10:56+00:00

This will be used by gfs2 to attach data to transactions for the journaled
data mode.  But the concept is generic enough that we might be able to
use it for other purposes like encryption/integrity post-processing in the
future.

Based on a patch from Andreas Gruenbacher.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong

iomap: generic inline data handling

2018-06-19T22:10:56+00:00

Add generic inline data handling by adding a pointer to the inline data
region to struct iomap.  When handling a buffered IOMAP_INLINE write,
iomap_write_begin will copy the current inline data from the inline data
region into the page cache, and iomap_write_end will copy the changes in
the page cache back to the inline data region.

This doesn't cover inline data reads and direct I/O yet because so far,
we have no users.

Signed-off-by: Andreas Gruenbacher 
[hch: small cleanups to better fit in with other iomap work]
Signed-off-by: Christoph Hellwig 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong

iomap: add an iomap-based bmap implementation

2018-06-02T01:37:33+00:00

This adds a simple iomap-based implementation of the legacy ->bmap
interface.  Note that we can't easily add checks for rt or reflink
files, so these will have to remain in the callers.  This interface
just needs to die..

Signed-off-by: Christoph Hellwig 
Reviewed-by: Dave Chinner 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong

iomap: move IOMAP_F_BOUNDARY to gfs2

2018-06-02T01:37:32+00:00

Just define a range of fs specific flags and use that in gfs2 instead of
exposing this internal flag globally.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Dave Chinner 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong

iomap: fix the comment describing IOMAP_NOWAIT

2018-06-02T01:37:32+00:00

Signed-off-by: Christoph Hellwig 
Reviewed-by: Dave Chinner 
Reviewed-by: Darrick J. Wong 
Signed-off-by: Darrick J. Wong