[PATCH v9 6/9] iomap: support direct I/O with fscrypt using blk-crypto

Satya Tangirala
2021-06-04T21:09:24Z

From: Eric Biggers <ebiggers@google.com>

Set bio crypt contexts on bios by calling into fscrypt when required.
No DUN contiguity checks are done - callers are expected to set up the
iomap correctly to ensure that each bio submitted by iomap will not have
blocks with incontiguous DUNs by calling fscrypt_limit_io_blocks()
appropriately.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Co-developed-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Satya Tangirala <satyat@google.com>
---
fs/iomap/direct-io.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/fs/iomap/direct-io.c b/fs/iomap/direct-io.c
index 9398b8c31323..1c825deb36a9 100644
--- a/fs/iomap/direct-io.c
+++ b/fs/iomap/direct-io.c
@@ -6,6 +6,7 @@
#include <linux/module.h>
#include <linux/compiler.h>
#include <linux/fs.h>
+#include <linux/fscrypt.h>
#include <linux/iomap.h>
#include <linux/backing-dev.h>
#include <linux/uio.h>
@@ -185,11 +186,14 @@ static void
iomap_dio_zero(struct iomap_dio *dio, struct iomap *iomap, loff_t pos,
unsigned len)
{
+ struct inode *inode = file_inode(dio->iocb->ki_filp);
struct page *page = ZERO_PAGE(0);
int flags = REQ_SYNC | REQ_IDLE;
struct bio *bio;

bio = bio_alloc(GFP_KERNEL, 1);
+ fscrypt_set_bio_crypt_ctx(bio, inode, pos >> inode->i_blkbits,
+ GFP_KERNEL);
bio_set_dev(bio, iomap->bdev);
bio->bi_iter.bi_sector = iomap_sector(iomap, pos);
bio->bi_private = dio;
@@ -306,6 +310,8 @@ iomap_dio_bio_actor(struct inode *inode, loff_t pos, loff_t length,
}

bio = bio_alloc(GFP_KERNEL, nr_pages);
+ fscrypt_set_bio_crypt_ctx(bio, inode, pos >> inode->i_blkbits,
+ GFP_KERNEL);
bio_set_dev(bio, iomap->bdev);
bio->bi_iter.bi_sector = iomap_sector(iomap, pos);
bio->bi_write_hint = dio->iocb->ki_hint;
--
2.32.0.rc1.229.g3e70b5a671-goog