[PATCH virtiofsd 2/3] virtiofsd: support per-file DAX negotiation in FUSE_INIT

[Jeffle Xu <jefflexu@linux.alibaba.com>]

Signed-off-by: Jeffle Xu <jefflexu@linux.alibaba.com>
---
 tools/virtiofsd/fuse_common.h    | 5 +++++
 tools/virtiofsd/fuse_lowlevel.c  | 6 ++++++
 tools/virtiofsd/passthrough_ll.c | 3 +++
 3 files changed, 14 insertions(+)

diff --git a/tools/virtiofsd/fuse_common.h b/tools/virtiofsd/fuse_common.h
index 8a75729be9..ee6fc64c23 100644
--- a/tools/virtiofsd/fuse_common.h
+++ b/tools/virtiofsd/fuse_common.h
@@ -372,6 +372,11 @@ struct fuse_file_info {
  */
 #define FUSE_CAP_HANDLE_KILLPRIV_V2 (1 << 28)
 
+/**
+ * Indicates support for per-file DAX.
+ */
+#define FUSE_CAP_PERFILE_DAX (1 << 29)
+
 /**
  * Ioctl flags
  *
diff --git a/tools/virtiofsd/fuse_lowlevel.c b/tools/virtiofsd/fuse_lowlevel.c
index 50fc5c8d5a..60fb82a92a 100644
--- a/tools/virtiofsd/fuse_lowlevel.c
+++ b/tools/virtiofsd/fuse_lowlevel.c
@@ -2065,6 +2065,9 @@ static void do_init(fuse_req_t req, fuse_ino_t nodeid,
     if (arg->flags & FUSE_HANDLE_KILLPRIV_V2) {
         se->conn.capable |= FUSE_CAP_HANDLE_KILLPRIV_V2;
     }
+    if (arg->flags & FUSE_PERFILE_DAX) {
+        se->conn.capable |= FUSE_CAP_PERFILE_DAX;
+    }
 #ifdef HAVE_SPLICE
 #ifdef HAVE_VMSPLICE
     se->conn.capable |= FUSE_CAP_SPLICE_WRITE | FUSE_CAP_SPLICE_MOVE;
@@ -2180,6 +2183,9 @@ static void do_init(fuse_req_t req, fuse_ino_t nodeid,
     if (se->conn.want & FUSE_CAP_POSIX_ACL) {
         outarg.flags |= FUSE_POSIX_ACL;
     }
+    if (se->conn.want & FUSE_CAP_PERFILE_DAX) {
+        outarg.flags |= FUSE_PERFILE_DAX;
+    }
     outarg.max_readahead = se->conn.max_readahead;
     outarg.max_write = se->conn.max_write;
     if (se->conn.max_background >= (1 << 16)) {
diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c
index b76d878509..da88304253 100644
--- a/tools/virtiofsd/passthrough_ll.c
+++ b/tools/virtiofsd/passthrough_ll.c
@@ -702,6 +702,9 @@ static void lo_init(void *userdata, struct fuse_conn_info *conn)
         conn->want &= ~FUSE_CAP_HANDLE_KILLPRIV_V2;
         lo->killpriv_v2 = 0;
     }
+    if (conn->capable & FUSE_CAP_PERFILE_DAX) {
+        conn->want |= FUSE_CAP_PERFILE_DAX;
+    }
 }
 
 static void lo_getattr(fuse_req_t req, fuse_ino_t ino,
-- 
2.27.0