WIP Remove special meaning of root directory inode

src/nfs_conn.cpp

@@ -38,22 +38,6 @@ static int nfs3_null_proc(void *opaque, rpc_op_t *rop)
     return 0;
 }
 
-static fattr3 get_root_attributes(nfs_client_t *self)
-{
-    return (fattr3){
-        .type = NF3DIR,
-        .mode = 0755,
-        .nlink = 1,
-        .uid = (uint32_t)self->parent->root_uid,
-        .gid = (uint32_t)self->parent->root_gid,
-        .size = 4096,
-        .used = 4096,
-        .rdev = (specdata3){ 0 },
-        .fsid = self->parent->fsid,
-        .fileid = 1,
-    };
-}
-
 static nfstime3 nfstime_from_str(const std::string & s)
 {
     nfstime3 t;
@@ -94,9 +78,11 @@ static fattr3 get_kv_attributes(nfs_client_t *self, uint64_t ino, json11::Json a
         .nlink = (nlink == 0 ? 1 : (uint32_t)nlink),
         .uid = (uint32_t)attrs["uid"].uint64_value(),
         .gid = (uint32_t)attrs["gid"].uint64_value(),
-        .size = attrs["size"].uint64_value(),
-        .used = attrs["alloc"].uint64_value(),
-        .rdev = (specdata3){ (uint32_t)attrs["major"].uint64_value(), (uint32_t)attrs["minor"].uint64_value() },
+        .size = (type == NF3DIR ? 4096 : attrs["size"].uint64_value()),
+        .used = (type == NF3DIR ? 4096 : attrs["alloc"].uint64_value()),
+        .rdev = (type == NF3BLK || type == NF3CHR
+            ? (specdata3){ (uint32_t)attrs["major"].uint64_value(), (uint32_t)attrs["minor"].uint64_value() }
+            : (specdata3){}),
         .fsid = self->parent->fsid,
         .fileid = ino,
         .atime = atime,
@@ -118,7 +104,11 @@ static std::string kv_direntry_key(uint64_t dir_ino, const std::string & filenam
     return (char*)key + filename;
 }
 
-static const std::string kv_next_id_key = "id";
+static uint64_t kv_root_inode = 1;
+
+static const char *kv_next_id_key = "id";
+
+static const char *kv_root_handle = "R";
 
 static std::string kv_direntry_filename(const std::string & key)
 {
@@ -161,12 +151,7 @@ static uint64_t kv_fh_inode(const std::string & fh)
 
 static bool kv_fh_valid(const std::string & fh)
 {
-    return fh == "R" || fh.size() == 9 && fh[0] == 'S' || fh.size() > 17 && fh[0] == 'I';
-}
-
-static bool kv_fh_is_root(const std::string & fh)
-{
-    return fh == "R";
+    return fh == kv_root_handle || fh.size() == 9 && fh[0] == 'S' || fh.size() > 17 && fh[0] == 'I';
 }
 
 // Attributes are always stored in the inode
@@ -176,6 +161,12 @@ static void kv_read_inode(nfs_client_t *self, uint64_t ino,
     auto key = kv_inode_key(ino);
     self->parent->db->get(key, [=](int res, const std::string & value)
     {
+        if (ino == kv_root_inode && res == -ENOENT)
+        {
+            // Allow root inode to not exist
+            cb(0, "", json11::Json(json11::Json::object{ { "type", NF3DIR } }));
+            return;
+        }
         if (res < 0)
         {
             if (res != -ENOENT)
@@ -206,18 +197,6 @@ static int nfs3_getattr_proc(void *opaque, rpc_op_t *rop)
         rpc_queue_reply(rop);
         return 0;
     }
-    if (kv_fh_is_root(fh))
-    {
-        // Root entry
-        *reply = (GETATTR3res){
-            .status = NFS3_OK,
-            .resok = (GETATTR3resok){
-                .obj_attributes = get_root_attributes(self),
-            },
-        };
-        rpc_queue_reply(rop);
-        return 0;
-    }
     auto ino = kv_fh_inode(fh);
     kv_read_inode(self, ino, [=](int res, const std::string & value, json11::Json attrs)
     {
@@ -306,7 +285,7 @@ resume_1:
     }, [st](int res, const std::string & cas_value)
     {
         st->cas_res = res;
-        return res == 0 && cas_value == st->ientry_text;
+        return (res == 0 || res == -ENOENT && st->ino == kv_root_inode) && cas_value == st->ientry_text;
     });
     return;
 resume_2:
@@ -367,14 +346,6 @@ static int nfs3_setattr_proc(void *opaque, rpc_op_t *rop)
         delete st;
         return 0;
     }
-    if (kv_fh_is_root(fh))
-    {
-        // Root entry - silently ignore changes
-        *reply = (SETATTR3res){ .status = NFS3_OK };
-        rpc_queue_reply(rop);
-        delete st;
-        return 0;
-    }
     st->ino = kv_fh_inode(fh);
     if (args->new_attributes.size.set_it)
         st->set_attrs["size"] = args->new_attributes.size.size;
@@ -493,7 +464,7 @@ static int nfs3_readlink_proc(void *opaque, rpc_op_t *rop)
     nfs_client_t *self = (nfs_client_t*)opaque;
     READLINK3args *args = (READLINK3args*)rop->request;
     READLINK3res *reply = (READLINK3res*)rop->reply;
-    if (!kv_fh_valid(args->symlink) || kv_fh_is_root(args->symlink))
+    if (!kv_fh_valid(args->symlink) || args->symlink == kv_root_handle)
     {
         // Invalid filehandle or trying to read symlink from root entry
         *reply = (READLINK3res){ .status = NFS3ERR_INVAL };
@@ -579,6 +550,7 @@ static int nfs3_read_proc(void *opaque, rpc_op_t *rop)
     return 1;
 }
 
+// FIXME: Pack small files into "common inodes"
 static void nfs_resize_write(nfs_client_t *self, rpc_op_t *rop, uint64_t inode, uint64_t new_size, uint64_t offset, uint64_t count, void *buf);
 
 static int nfs3_write_proc(void *opaque, rpc_op_t *rop)
@@ -1603,7 +1575,6 @@ static int nfs3_rename_proc(void *opaque, rpc_op_t *rop)
     st->new_dir_ino = kv_fh_inode(args->to.dir);
     st->old_name = args->from.name;
     st->new_name = args->to.name;
-    // FIXME: 0 = root ino?
     if (!st->old_dir_ino || !st->new_dir_ino || st->old_name == "" || st->new_name == "")
     {
         RENAME3res *reply = (RENAME3res*)rop->reply;
@@ -1949,30 +1920,32 @@ resume_2:
                 cb(st->res);
                 return;
             }
-            auto fh = kv_fh(st->parent_ino);
-            auto entry_size = 20 + 4/*len_pad4("..")*/ + (st->is_plus ? 8 + 88 + len_pad4(fh.size()) : 0);
-            if (st->reply_size + entry_size > st->maxcount)
-            {
-                st->eof = false;
-                auto cb = std::move(st->cb);
-                cb(0);
-                return;
-            }
-            entryplus3 dotdot;
-            dotdot.name = xdr_copy_string(st->rop->xdrs, "..");
-            dotdot.fileid = st->dir_ino;
-            dotdot.name_attributes = (post_op_attr){
-                // FIXME: maybe do not read parent attributes and leave them to a GETATTR?
-                .attributes_follow = 1,
-                .attributes = get_kv_attributes(st->self, st->parent_ino, st->parent_ientry),
-            };
-            dotdot.name_handle = (post_op_fh3){
-                .handle_follows = 1,
-                .handle = xdr_copy_string(st->rop->xdrs, fh),
-            };
-            st->entries.push_back(dotdot);
-            st->reply_size += entry_size;
         }
+        auto fh = kv_fh(st->parent_ino);
+        auto entry_size = 20 + 4/*len_pad4("..")*/ + (st->is_plus ? 8 + 88 + len_pad4(fh.size()) : 0);
+        if (st->reply_size + entry_size > st->maxcount)
+        {
+            st->eof = false;
+            auto cb = std::move(st->cb);
+            cb(0);
+            return;
+        }
+        entryplus3 dotdot;
+        dotdot.name = xdr_copy_string(st->rop->xdrs, "..");
+        dotdot.fileid = st->dir_ino;
+        dotdot.name_attributes = (post_op_attr){
+            // FIXME: maybe do not read parent attributes and leave them to a GETATTR?
+            .attributes_follow = 1,
+            .attributes = get_kv_attributes(st->self,
+                st->parent_ino ? st->parent_ino : st->dir_ino,
+                st->parent_ino ? st->parent_ientry : st->ientry),
+        };
+        dotdot.name_handle = (post_op_fh3){
+            .handle_follows = 1,
+            .handle = xdr_copy_string(st->rop->xdrs, fh),
+        };
+        st->entries.push_back(dotdot);
+        st->reply_size += entry_size;
     }
     st->prefix = kv_direntry_key(st->dir_ino, "");
     st->eof = true;
@@ -2181,8 +2154,8 @@ static int nfs3_fsstat_proc(void *opaque, rpc_op_t *rop)
         .status = NFS3_OK,
         .resok = (FSSTAT3resok){
             .obj_attributes = {
-                .attributes_follow = 1,
-                .attributes = get_root_attributes(self),
+                .attributes_follow = 0,
+                //.attributes = get_root_attributes(self),
             },
             .tbytes = tbytes, // total bytes
             .fbytes = fbytes, // free bytes
@@ -2199,12 +2172,11 @@ static int nfs3_fsstat_proc(void *opaque, rpc_op_t *rop)
 
 static int nfs3_fsinfo_proc(void *opaque, rpc_op_t *rop)
 {
-    nfs_client_t *self = (nfs_client_t*)opaque;
+    //nfs_client_t *self = (nfs_client_t*)opaque;
     FSINFO3args *args = (FSINFO3args*)rop->request;
     FSINFO3res *reply = (FSINFO3res*)rop->reply;
-    if (args->fsroot != "roothandle")
+    if (args->fsroot != kv_root_handle)
     {
-        // Example error
         *reply = (FSINFO3res){ .status = NFS3ERR_INVAL };
     }
     else
@@ -2214,8 +2186,8 @@ static int nfs3_fsinfo_proc(void *opaque, rpc_op_t *rop)
             .status = NFS3_OK,
             .resok = (FSINFO3resok){
                 .obj_attributes = {
-                    .attributes_follow = 1,
-                    .attributes = get_root_attributes(self),
+                    .attributes_follow = 0,
+                    //.attributes = get_root_attributes(self),
                 },
                 .rtmax = 128*1024*1024,
                 .rtpref = 128*1024*1024,
@@ -2242,15 +2214,13 @@ static int nfs3_pathconf_proc(void *opaque, rpc_op_t *rop)
     //nfs_client_t *self = (nfs_client_t*)opaque;
     PATHCONF3args *args = (PATHCONF3args*)rop->request;
     PATHCONF3res *reply = (PATHCONF3res*)rop->reply;
-    if (args->object != "roothandle")
+    if (args->object != kv_root_handle)
     {
-        // Example error
         *reply = (PATHCONF3res){ .status = NFS3ERR_INVAL };
     }
     else
     {
         // Fill info
-        bool_t x = FALSE;
         *reply = (PATHCONF3res){
             .status = NFS3_OK,
             .resok = (PATHCONF3resok){
@@ -2258,7 +2228,8 @@ static int nfs3_pathconf_proc(void *opaque, rpc_op_t *rop)
                     // Without at least one reference to a non-constant value (local variable or something else),
                     // with gcc 8 we get "internal compiler error: side-effects element in no-side-effects CONSTRUCTOR" here
                     // FIXME: get rid of this after raising compiler requirement
-                    .attributes_follow = x,
+                    .attributes_follow = 0,
+                    //.attributes = get_root_attributes(self),
                 },
                 .linkmax = 0,
                 .name_max = 255,
@@ -2298,7 +2269,7 @@ static int mount3_mnt_proc(void *opaque, rpc_op_t *rop)
     nfs_mountres3 *reply = (nfs_mountres3*)rop->reply;
     u_int flavor = RPC_AUTH_NONE;
     reply->fhs_status = MNT3_OK;
-    reply->mountinfo.fhandle = xdr_copy_string(rop->xdrs, "roothandle");
+    reply->mountinfo.fhandle = xdr_copy_string(rop->xdrs, kv_root_handle);
     reply->mountinfo.auth_flavors.auth_flavors_len = 1;
     reply->mountinfo.auth_flavors.auth_flavors_val = (u_int*)xdr_copy_string(rop->xdrs, (char*)&flavor, sizeof(u_int)).data;
     rpc_queue_reply(rop);