libfuse: add copy_file_range() support

Add support for the relatively new copy_file_range() syscall. Backend
filesystems can now implement an efficient way of cloning/duplicating
data ranges within files. See 'man 2 copy_file_range' for more details.

1 files changed, 22 insertions, 0 deletions

diff --git a/lib/fuse_lowlevel.c b/lib/fuse_lowlevel.c
index 844e797..cd59ec0 100644
--- a/lib/fuse_lowlevel.c
+++ b/lib/fuse_lowlevel.c
@@ -1810,6 +1810,27 @@ static void do_fallocate(fuse_req_t req, fuse_ino_t nodeid, const void *inarg)
 		fuse_reply_err(req, ENOSYS);
 }
 
+static void do_copy_file_range(fuse_req_t req, fuse_ino_t nodeid_in, const void *inarg)
+{
+	struct fuse_copy_file_range_in *arg = (struct fuse_copy_file_range_in *) inarg;
+	struct fuse_file_info fi_in, fi_out;
+
+	memset(&fi_in, 0, sizeof(fi_in));
+	fi_in.fh = arg->fh_in;
+
+	memset(&fi_out, 0, sizeof(fi_out));
+	fi_out.fh = arg->fh_out;
+
+
+	if (req->se->op.copy_file_range)
+		req->se->op.copy_file_range(req, nodeid_in, arg->off_in,
+					    &fi_in, arg->nodeid_out,
+					    arg->off_out, &fi_out, arg->len,
+					    arg->flags);
+	else
+		fuse_reply_err(req, ENOSYS);
+}
+
 static void do_init(fuse_req_t req, fuse_ino_t nodeid, const void *inarg)
 {
 	struct fuse_init_in *arg = (struct fuse_init_in *) inarg;
@@ -2395,6 +2416,7 @@ static struct {
 	[FUSE_BATCH_FORGET] = { do_batch_forget, "BATCH_FORGET" },
 	[FUSE_READDIRPLUS] = { do_readdirplus,	"READDIRPLUS"},
 	[FUSE_RENAME2]     = { do_rename2,      "RENAME2"    },
+	[FUSE_COPY_FILE_RANGE] = { do_copy_file_range, "COPY_FILE_RANGE" },
 	[CUSE_INIT]	   = { cuse_lowlevel_init, "CUSE_INIT"   },
 };