ocfs2: implement the VFS clone_range, copy_range, and dedupe_range features

Connect the new VFS clone_range, copy_range, and dedupe_range features
to the existing reflink capability of ocfs2.  Compared to the existing
ocfs2 reflink ioctl We have to do things a little differently to support
the VFS semantics (we can clone subranges of a file but we don't clone
xattrs), but the VFS ioctls are more broadly supported.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
v2: Convert inline data files to extents files before reflinking,
and fix i_blocks so that stat(2) output is correct.
v3: Make zero-length dedupe consistent with btrfs behavior.
v4: Use VFS double-inode lock routines and remove MAX_DEDUPE_LEN.

1 files changed, 32 insertions, 3 deletions

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index d261f3a91870..c4889655d32b 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1667,9 +1667,9 @@ static void ocfs2_calc_trunc_pos(struct inode *inode,
         *done = ret;
 }
 
-static int ocfs2_remove_inode_range(struct inode *inode,
-                                    struct buffer_head *di_bh, u64 byte_start,
-                                    u64 byte_len)
+int ocfs2_remove_inode_range(struct inode *inode,
+                             struct buffer_head *di_bh, u64 byte_start,
+                             u64 byte_len)
 {
         int ret = 0, flags = 0, done = 0, i;
         u32 trunc_start, trunc_len, trunc_end, trunc_cpos, phys_cpos;
@@ -2439,6 +2439,31 @@ out:
         return offset;
 }
 
+static int ocfs2_file_clone_range(struct file *file_in,
+                                  loff_t pos_in,
+                                  struct file *file_out,
+                                  loff_t pos_out,
+                                  u64 len)
+{
+        return ocfs2_reflink_remap_range(file_in, pos_in, file_out, pos_out,
+                                         len, false);
+}
+
+static ssize_t ocfs2_file_dedupe_range(struct file *src_file,
+                                       u64 loff,
+                                       u64 len,
+                                       struct file *dst_file,
+                                       u64 dst_loff)
+{
+        int error;
+
+        error = ocfs2_reflink_remap_range(src_file, loff, dst_file, dst_loff,
+                                          len, true);
+        if (error)
+                return error;
+        return len;
+}
+
 const struct inode_operations ocfs2_file_iops = {
         .setattr        = ocfs2_setattr,
         .getattr        = ocfs2_getattr,
@@ -2478,6 +2503,8 @@ const struct file_operations ocfs2_fops = {
         .splice_read    = generic_file_splice_read,
         .splice_write   = iter_file_splice_write,
         .fallocate      = ocfs2_fallocate,
+        .clone_file_range = ocfs2_file_clone_range,
+        .dedupe_file_range = ocfs2_file_dedupe_range,
 };
 
 const struct file_operations ocfs2_dops = {
@@ -2523,6 +2550,8 @@ const struct file_operations ocfs2_fops_no_plocks = {
         .splice_read    = generic_file_splice_read,
         .splice_write   = iter_file_splice_write,
         .fallocate      = ocfs2_fallocate,
+        .clone_file_range = ocfs2_file_clone_range,
+        .dedupe_file_range = ocfs2_file_dedupe_range,
 };
 
 const struct file_operations ocfs2_dops_no_plocks = {