success and future calls to open and release will also succeed without being sent to the filesystem process. Valid replies: fuse_reply_open fuse_reply_err Parameters req request handle ino the inode number :/tmp/fsmount# strace ./main ... open("in.txt", O_WRONLY|O_CREAT, 0200) = 3 O_EXCL # O_WRONLY|O_CREAT|O_EXCL # in.txt 0200 root@pubbeta1-nostest2:/tmp/fsmount# strace ./main ... open("in.txt", O_WRONLY|O_CREAT|O_EXCL smount$ strace ./main ... open("in.txt", O_RDONLY) = -1 EACCES (Permission denied) # O_WRONLY|O_APPEND # in.txt 0400 nbs@pubbeta1-nostest2:/tmp/fsmount$ strace ./main ... open("in.txt"

1 0 13:44 pts/213 00:00:00 ./bazel-bin/curvefs/src/space_allocator/curve_fs_space_allocator_main wanghai+ 2641514 1 0 13:44 pts/213 00:00:00 ./bazel-bin/curvefs/src/metaserver/curvefs_metaserver Version table: 2.2.52-3+b1 500 500 http://debian.hz.netease.com/debian-current stretch/main amd64 Packages root@pubbeta2-curve5:/home/nbs# apt-get install acl root@pubbeta2-curve5:/home/nbs# https://unix.stackexchange.com/questions/325473/in-fuse-how-do-i-get-the-information-about-the-user-and-the-process-that-is-try https://wiki.gentoo.org/wiki/Filesystem/Access_Control_List_Guide https://www.usenix

server接口获取文件系统元数据信息，调用meta server接口获取文件和目录信息等 与现有块设备client交互，调用块设备接口，对卷进行读写。 向上对接fuse接口，协调上述模块交互，实现功能。 main 主函数模块，类似deamon，接收mount消息并处理（fuse session）。 除上述功能以外，还需实现文件系统创建和fuse挂载工具，功能主要是： 创建文件系统，指定文件系统的名字、卷大小（多文件系统）、 server，可先不实现） copyset cache & topo cache （可先不实现） mds client meta server client curve client （适配层） fuse impl main© XXX Page 10 of 11 接口设计 相关接口设计，见curve文件系统元数据proto（代码接口定义，已实现） Cache设计 Client的重要部分，就是上述这些cache

the NEBDServer, which affects services in few seconds. CurveBS IO processing flow Overall process The flow of user's read and write request to curve: 1. The user initiates a request (fd=1