ext4 crypto: implement the ext4 encryption write path
Pulls block_write_begin() into fs/ext4/inode.c because it might need
to do a low-level read of the existing data, in which case we need to
decrypt it.
Signed-off-by: Michael Halcrow <mhalcrow@google.com>
Signed-off-by: Ildar Muslukhov <ildarm@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 74580ea..973816b 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -3122,6 +3122,9 @@
ee_len = ext4_ext_get_actual_len(ex);
ee_pblock = ext4_ext_pblock(ex);
+ if (ext4_encrypted_inode(inode))
+ return ext4_encrypted_zeroout(inode, ex);
+
ret = sb_issue_zeroout(inode->i_sb, ee_pblock, ee_len, GFP_NOFS);
if (ret > 0)
ret = 0;
@@ -4898,6 +4901,20 @@
ext4_lblk_t lblk;
unsigned int blkbits = inode->i_blkbits;
+ /*
+ * Encrypted inodes can't handle collapse range or insert
+ * range since we would need to re-encrypt blocks with a
+ * different IV or XTS tweak (which are based on the logical
+ * block number).
+ *
+ * XXX It's not clear why zero range isn't working, but we'll
+ * leave it disabled for encrypted inodes for now. This is a
+ * bug we should fix....
+ */
+ if (ext4_encrypted_inode(inode) &&
+ (mode & (FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE)))
+ return -EOPNOTSUPP;
+
/* Return error if mode is not supported */
if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE |
FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_ZERO_RANGE))