ceph: get file size from fscrypt_file when present in inode traces

When we get an inode trace from the MDS, grab the fscrypt_file field if
the inode is encrypted, and use it to populate the i_size field instead
of the regular inode size field.

Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>

diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 67a2421ed092bcf7892d8109cb95eba49c3d44b1..4db19fc341a47e1b2a31fa7f295270870acf9cc7 100644 (file)
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -1036,6 +1036,7 @@ int ceph_fill_inode(struct inode *inode, struct page *locked_page,
 
        if (new_version ||
            (new_issued & (CEPH_CAP_ANY_FILE_RD | CEPH_CAP_ANY_FILE_WR))) {
+               u64 size = le64_to_cpu(info->size);
                s64 old_pool = ci->i_layout.pool_id;
                struct ceph_string *old_ns;
 
@@ -1049,11 +1050,21 @@ int ceph_fill_inode(struct inode *inode, struct page *locked_page,
 
                pool_ns = old_ns;
 
+               if (IS_ENCRYPTED(inode) && size && (iinfo->fscrypt_file_len == sizeof(__le64))) {
+                       u64 fsize = __le64_to_cpu(*(__le64 *)iinfo->fscrypt_file);
+
+                       if (size == round_up(fsize, CEPH_FSCRYPT_BLOCK_SIZE)) {
+                               size = fsize;
+                       } else {
+                               pr_warn("fscrypt size mismatch: size=%llu fscrypt_file=%llu, discarding fscrypt_file size.\n",
+                                       info->size, size);
+                       }
+               }
+
                queue_trunc = ceph_fill_file_size(inode, issued,
                                        le32_to_cpu(info->truncate_seq),
                                        le64_to_cpu(info->truncate_size),
-                                       le64_to_cpu(info->size),
-                                       info_caps);
+                                       size, info_caps);
                /* only update max_size on auth cap */
                if ((info->cap.flags & CEPH_CAP_FLAG_AUTH) &&
                    ci->i_max_size != le64_to_cpu(info->max_size)) {