forked from Minki/linux
378f32bab3
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> Link: https://lore.kernel.org/r/e55db6f12ae6ff017f36774135e79f3e7b0333da.1572949325.git.mbobrowski@mbobrowski.org Signed-off-by: Theodore Ts'o <tytso@mit.edu> |
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| .. | ||
| acl.c | ||
| acl.h | ||
| balloc.c | ||
| bitmap.c | ||
| block_validity.c | ||
| dir.c | ||
| ext4_extents.h | ||
| ext4_jbd2.c | ||
| ext4_jbd2.h | ||
| ext4.h | ||
| extents_status.c | ||
| extents_status.h | ||
| extents.c | ||
| file.c | ||
| fsmap.c | ||
| fsmap.h | ||
| fsync.c | ||
| hash.c | ||
| ialloc.c | ||
| indirect.c | ||
| inline.c | ||
| inode.c | ||
| ioctl.c | ||
| Kconfig | ||
| Makefile | ||
| mballoc.c | ||
| mballoc.h | ||
| migrate.c | ||
| mmp.c | ||
| move_extent.c | ||
| namei.c | ||
| page-io.c | ||
| readpage.c | ||
| resize.c | ||
| super.c | ||
| symlink.c | ||
| sysfs.c | ||
| truncate.h | ||
| verity.c | ||
| xattr_security.c | ||
| xattr_trusted.c | ||
| xattr_user.c | ||
| xattr.c | ||
| xattr.h | ||