UDF: Add support for O_DIRECT

Add support for the O_DIRECT flag.  There are two cases to deal with:

1. Small files stored in the ICB (inode control block?): just return 0
from the new udf_adinicb_direct_IO() handler to fall back to buffered
I/O.

2. Larger files, not stored in the ICB: nothing special here.  Just call
blockdev_direct_IO() from our new udf_direct_IO() handler and tidy up
any blocks instantiated outside i_size on error.  This is pretty
standard.  Factor error handling code out of udf_write_begin() into new
function udf_write_failed() so it can also be called by udf_direct_IO().

Also change the whitespace in udf_aops to make it a bit neater.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Ian Abbott
2012-09-05 17:44:31 +01:00
committed by Jan Kara
parent 3f6bba8237
commit 5eec54fcde
3 changed files with 45 additions and 16 deletions

View File

@ -118,11 +118,20 @@ static int udf_adinicb_write_end(struct file *file,
return simple_write_end(file, mapping, pos, len, copied, page, fsdata);
}
static ssize_t udf_adinicb_direct_IO(int rw, struct kiocb *iocb,
const struct iovec *iov,
loff_t offset, unsigned long nr_segs)
{
/* Fallback to buffered I/O. */
return 0;
}
const struct address_space_operations udf_adinicb_aops = {
.readpage = udf_adinicb_readpage,
.writepage = udf_adinicb_writepage,
.write_begin = udf_adinicb_write_begin,
.write_end = udf_adinicb_write_end,
.direct_IO = udf_adinicb_direct_IO,
};
static ssize_t udf_file_aio_write(struct kiocb *iocb, const struct iovec *iov,