ext4: let fiemap work with inline data

fiemap is used to find the disk layout of a file, as for inline data,
let us just pretend like a file with just one extent.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 35 insertions, 0 deletions

diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
index fc3629980925..bf5f77803885 100644
--- a/fs/ext4/inline.c
+++ b/fs/ext4/inline.c
@@ -15,6 +15,7 @@
 #include "ext4.h"
 #include "xattr.h"
 #include "truncate.h"
+#include <linux/fiemap.h>
 
 #define EXT4_XATTR_SYSTEM_DATA  "data"
 #define EXT4_MIN_INLINE_DATA_SIZE       ((sizeof(__le32) * EXT4_N_BLOCKS))
@@ -1680,3 +1681,37 @@ int ext4_destroy_inline_data(handle_t *handle, struct inode *inode)
 
         return ret;
 }
+
+int ext4_inline_data_fiemap(struct inode *inode,
+                            struct fiemap_extent_info *fieinfo,
+                            int *has_inline)
+{
+        __u64 physical = 0;
+        __u64 length;
+        __u32 flags = FIEMAP_EXTENT_DATA_INLINE | FIEMAP_EXTENT_LAST;
+        int error = 0;
+        struct ext4_iloc iloc;
+
+        down_read(&EXT4_I(inode)->xattr_sem);
+        if (!ext4_has_inline_data(inode)) {
+                *has_inline = 0;
+                goto out;
+        }
+
+        error = ext4_get_inode_loc(inode, &iloc);
+        if (error)
+                goto out;
+
+        physical = iloc.bh->b_blocknr << inode->i_sb->s_blocksize_bits;
+        physical += (char *)ext4_raw_inode(&iloc) - iloc.bh->b_data;
+        physical += offsetof(struct ext4_inode, i_block);
+        length = i_size_read(inode);
+
+        if (physical)
+                error = fiemap_fill_next_extent(fieinfo, 0, physical,
+                                                length, flags);
+        brelse(iloc.bh);
+out:
+        up_read(&EXT4_I(inode)->xattr_sem);
+        return (error < 0 ? error : 0);
+}