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>
diff --git a/fs/udf/file.c b/fs/udf/file.c
index d1c6093..77b5953 100644
--- a/fs/udf/file.c
+++ b/fs/udf/file.c
@@ -118,11 +118,20 @@
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,