forked from TencentOS/TencentOS-kernel
146ec6c502
commit: 378f32bab3714f04c4e0c3aee4129f6703805550 This patch introduces a new direct I/O write path which makes use of the iomap infrastructure. All direct I/O writes are now passed from the ->write_iter() callback through to the new direct I/O handler ext4_dio_write_iter(). This function is responsible for calling into the iomap infrastructure via iomap_dio_rw(). Code snippets from the existing direct I/O write code within ext4_file_write_iter() such as, checking whether the I/O request is unaligned asynchronous I/O, or whether the write will result in an overwrite have effectively been moved out and into the new direct I/O ->write_iter() handler. The block mapping flags that are eventually passed down to ext4_map_blocks() from the *_get_block_*() suite of routines have been taken out and introduced within ext4_iomap_alloc(). For inode extension cases, ext4_handle_inode_extension() is effectively the function responsible for performing such metadata updates. This is called after iomap_dio_rw() has returned so that we can safely determine whether we need to potentially truncate any allocated blocks that may have been prepared for this direct I/O write. We don't perform the inode extension, or truncate operations from the ->end_io() handler as we don't have the original I/O 'length' available there. The ->end_io() however is responsible fo converting allocated unwritten extents to written extents. In the instance of a short write, we fallback and complete the remainder of the I/O using buffered I/O via ext4_buffered_write_iter(). The existing buffer_head direct I/O implementation has been removed as it's now redundant. [ Fix up ext4_dio_write_iter() per Jan's comments at https://lore.kernel.org/r/20191105135932.GN22379@quack2.suse.cz -- TYT ] Signed-off-by: Matthew Bobrowski <mbobrowski@mbobrowski.org> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> |
||
|---|---|---|
| .. | ||
| Kconfig | ||
| Makefile | ||
| acl.c | ||
| acl.h | ||
| aops.c | ||
| aops.h | ||
| bmap.c | ||
| bmap.h | ||
| dentry.c | ||
| dir.c | ||
| dir.h | ||
| export.c | ||
| file.c | ||
| gfs2.h | ||
| glock.c | ||
| glock.h | ||
| glops.c | ||
| glops.h | ||
| incore.h | ||
| inode.c | ||
| inode.h | ||
| lock_dlm.c | ||
| log.c | ||
| log.h | ||
| lops.c | ||
| lops.h | ||
| main.c | ||
| meta_io.c | ||
| meta_io.h | ||
| ops_fstype.c | ||
| quota.c | ||
| quota.h | ||
| recovery.c | ||
| recovery.h | ||
| rgrp.c | ||
| rgrp.h | ||
| super.c | ||
| super.h | ||
| sys.c | ||
| sys.h | ||
| trace_gfs2.h | ||
| trans.c | ||
| trans.h | ||
| util.c | ||
| util.h | ||
| xattr.c | ||
| xattr.h | ||