[PATCH v7 23/43] btrfs: keep track of fscrypt info and orig_start for dio reads

[Daniel Vacek <neelx@suse.com>]

From: Josef Bacik <josef@toxicpanda.com>

We keep track of this information in the ordered extent for writes, but
we need it for reads as well.  Add fscrypt_extent_info and orig_start to
the dio_data so we can populate this on reads.  This will be used later
when we attach the fscrypt context to the bios.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Daniel Vacek <neelx@suse.com>
---

No changes in v7.
v6 changes:
 * Open-code orig_start to start - offset.
v5: https://lore.kernel.org/linux-btrfs/acf3d79bcd72a4447b2993e78d9742fa5a05397f.1706116485.git.josef@toxicpanda.com/
---
 fs/btrfs/direct-io.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/fs/btrfs/direct-io.c b/fs/btrfs/direct-io.c
index e46bca590f35..f87656db6157 100644
--- a/fs/btrfs/direct-io.c
+++ b/fs/btrfs/direct-io.c
@@ -17,6 +17,8 @@ struct btrfs_dio_data {
 	ssize_t submitted;
 	struct extent_changeset *data_reserved;
 	struct btrfs_ordered_extent *ordered;
+	struct fscrypt_extent_info *fscrypt_info;
+	u64 orig_start;
 	bool data_space_reserved;
 	bool nocow_done;
 };
@@ -550,6 +552,9 @@ static int btrfs_dio_iomap_begin(struct inode *inode, loff_t start,
 							       release_offset,
 							       release_len);
 		}
+	} else {
+		dio_data->fscrypt_info = fscrypt_get_extent_info(em->fscrypt_info);
+		dio_data->orig_start = em->start - em->offset;
 	}
 
 	/*
@@ -640,6 +645,11 @@ static int btrfs_dio_iomap_end(struct inode *inode, loff_t pos, loff_t length,
 		dio_data->ordered = NULL;
 	}
 
+	if (dio_data->fscrypt_info) {
+		fscrypt_put_extent_info(dio_data->fscrypt_info);
+		dio_data->fscrypt_info = NULL;
+	}
+
 	if (write)
 		extent_changeset_free(dio_data->data_reserved);
 	return ret;
-- 
2.53.0