1==== 2TODO 3==== 4 5Version 2.14 December 21, 2018 6 7A Partial List of Missing Features 8================================== 9 10Contributions are welcome. There are plenty of opportunities 11for visible, important contributions to this module. Here 12is a partial list of the known problems and missing features: 13 14a) SMB3 (and SMB3.1.1) missing optional features: 15 16 - multichannel (started), integration with RDMA 17 - directory leases (improved metadata caching), started (root dir only) 18 - T10 copy offload ie "ODX" (copy chunk, and "Duplicate Extents" ioctl 19 currently the only two server side copy mechanisms supported) 20 21b) improved sparse file support (fiemap and SEEK_HOLE are implemented 22 but additional features would be supportable by the protocol). 23 24c) Directory entry caching relies on a 1 second timer, rather than 25 using Directory Leases, currently only the root file handle is cached longer 26 27d) quota support (needs minor kernel change since quota calls 28 to make it to network filesystems or deviceless filesystems) 29 30e) Additional use cases can be optimized to use "compounding" (e.g. 31 open/query/close and open/setinfo/close) to reduce the number of 32 roundtrips to the server and improve performance. Various cases 33 (stat, statfs, create, unlink, mkdir) already have been improved by 34 using compounding but more can be done. In addition we could 35 significantly reduce redundant opens by using deferred close (with 36 handle caching leases) and better using reference counters on file 37 handles. 38 39f) Finish inotify support so kde and gnome file list windows 40 will autorefresh (partially complete by Asser). Needs minor kernel 41 vfs change to support removing D_NOTIFY on a file. 42 43g) Add GUI tool to configure /proc/fs/cifs settings and for display of 44 the CIFS statistics (started) 45 46h) implement support for security and trusted categories of xattrs 47 (requires minor protocol extension) to enable better support for SELINUX 48 49i) Add support for tree connect contexts (see MS-SMB2) a new SMB3.1.1 protocol 50 feature (may be especially useful for virtualization). 51 52j) Create UID mapping facility so server UIDs can be mapped on a per 53 mount or a per server basis to client UIDs or nobody if no mapping 54 exists. Also better integration with winbind for resolving SID owners 55 56k) Add tools to take advantage of more smb3 specific ioctls and features 57 (passthrough ioctl/fsctl is now implemented in cifs.ko to allow 58 sending various SMB3 fsctls and query info and set info calls 59 directly from user space) Add tools to make setting various non-POSIX 60 metadata attributes easier from tools (e.g. extending what was done 61 in smb-info tool). 62 63l) encrypted file support 64 65m) improved stats gathering tools (perhaps integration with nfsometer?) 66 to extend and make easier to use what is currently in /proc/fs/cifs/Stats 67 68n) Add support for claims based ACLs ("DAC") 69 70o) mount helper GUI (to simplify the various configuration options on mount) 71 72p) Add support for witness protocol (perhaps ioctl to cifs.ko from user space 73 tool listening on witness protocol RPC) to allow for notification of share 74 move, server failover, and server adapter changes. And also improve other 75 failover scenarios, e.g. when client knows multiple DFS entries point to 76 different servers, and the server we are connected to has gone down. 77 78q) Allow mount.cifs to be more verbose in reporting errors with dialect 79 or unsupported feature errors. 80 81r) updating cifs documentation, and user guide. 82 83s) Addressing bugs found by running a broader set of xfstests in standard 84 file system xfstest suite. 85 86t) split cifs and smb3 support into separate modules so legacy (and less 87 secure) CIFS dialect can be disabled in environments that don't need it 88 and simplify the code. 89 90v) POSIX Extensions for SMB3.1.1 (started, create and mkdir support added 91 so far). 92 93w) Add support for additional strong encryption types, and additional spnego 94 authentication mechanisms (see MS-SMB2) 95 96x) Finish support for SMB3.1.1 compression 97 98Known Bugs 99========== 100 101See https://bugzilla.samba.org - search on product "CifsVFS" for 102current bug list. Also check http://bugzilla.kernel.org (Product = File System, Component = CIFS) 103 1041) existing symbolic links (Windows reparse points) are recognized but 105 can not be created remotely. They are implemented for Samba and those that 106 support the CIFS Unix extensions, although earlier versions of Samba 107 overly restrict the pathnames. 1082) follow_link and readdir code does not follow dfs junctions 109 but recognizes them 110 111Misc testing to do 112================== 1131) check out max path names and max path name components against various server 114 types. Try nested symlinks (8 deep). Return max path name in stat -f information 115 1162) Improve xfstest's cifs/smb3 enablement and adapt xfstests where needed to test 117 cifs/smb3 better 118 1193) Additional performance testing and optimization using iozone and similar - 120 there are some easy changes that can be done to parallelize sequential writes, 121 and when signing is disabled to request larger read sizes (larger than 122 negotiated size) and send larger write sizes to modern servers. 123 1244) More exhaustively test against less common servers 125 1265) Continue to extend the smb3 "buildbot" which does automated xfstesting 127 against Windows, Samba and Azure currently - to add additional tests and 128 to allow the buildbot to execute the tests faster. The URL for the 129 buildbot is: http://smb3-test-rhel-75.southcentralus.cloudapp.azure.com 130 1316) Address various coverity warnings (most are not bugs per-se, but 132 the more warnings are addressed, the easier it is to spot real 133 problems that static analyzers will point out in the future). 134