kernel/include/linux/iomap.h, branch linux-5.2.y

iomap: Add a page_prepare callback

2019-05-01T14:47:37Z

Move the page_done callback into a separate iomap_page_ops structure and add a page_prepare calback to be called before the next page is written to. In gfs2, we'll want to start a transaction in page_prepare and end it in page_done. Other filesystems that implement data journaling will require the same kind of mechanism. Signed-off-by: Andreas Gruenbacher Reviewed-by: Christoph Hellwig Reviewed-by: Jan Kara Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong

iomap: wire up the iopoll method

2019-02-24T15:20:17Z

Store the request queue the last bio was submitted to in the iocb private data in addition to the cookie so that we find the right block device. Also refactor the common direct I/O bio submission code into a nice little helper. Signed-off-by: Christoph Hellwig Modified to use bio_set_polled(). Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe

fs/iomap.c: change return type to vm_fault_t

2018-10-26T23:25:18Z

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

2018-07-12T05:26:05Z

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

2018-06-20T16:32:41Z

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

2018-06-19T22:10:57Z

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

2018-06-19T22:10:57Z

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

2018-06-19T22:10:56Z

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

2018-06-19T22:10:56Z

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

2018-06-02T01:37:33Z

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