todo.rst (5968B)
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 (partially integrated), integration of multichannel with RDMA 17 - directory leases (improved metadata caching). Currently only implemented for root dir 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 such 23 as FALLOC_FL_COLLAPSE_RANGE and FALLOC_FL_INSERT_RANGE) 24 25c) Directory entry caching relies on a 1 second timer, rather than 26 using Directory Leases, currently only the root file handle is cached longer 27 by leveraging Directory Leases 28 29d) quota support (needs minor kernel change since quota calls otherwise 30 won't make it to network filesystems or deviceless filesystems). 31 32e) Additional use cases can be optimized to use "compounding" (e.g. 33 open/query/close and open/setinfo/close) to reduce the number of 34 roundtrips to the server and improve performance. Various cases 35 (stat, statfs, create, unlink, mkdir, xattrs) already have been improved by 36 using compounding but more can be done. In addition we could 37 significantly reduce redundant opens by using deferred close (with 38 handle caching leases) and better using reference counters on file 39 handles. 40 41f) Finish inotify support so kde and gnome file list windows 42 will autorefresh (partially complete by Asser). Needs minor kernel 43 vfs change to support removing D_NOTIFY on a file. 44 45g) Add GUI tool to configure /proc/fs/cifs settings and for display of 46 the CIFS statistics (started) 47 48h) implement support for security and trusted categories of xattrs 49 (requires minor protocol extension) to enable better support for SELINUX 50 51i) Add support for tree connect contexts (see MS-SMB2) a new SMB3.1.1 protocol 52 feature (may be especially useful for virtualization). 53 54j) Create UID mapping facility so server UIDs can be mapped on a per 55 mount or a per server basis to client UIDs or nobody if no mapping 56 exists. Also better integration with winbind for resolving SID owners 57 58k) Add tools to take advantage of more smb3 specific ioctls and features 59 (passthrough ioctl/fsctl is now implemented in cifs.ko to allow 60 sending various SMB3 fsctls and query info and set info calls 61 directly from user space) Add tools to make setting various non-POSIX 62 metadata attributes easier from tools (e.g. extending what was done 63 in smb-info tool). 64 65l) encrypted file support (currently the attribute showing the file is 66 encrypted on the server is reported, but changing the attribute is not 67 supported). 68 69m) improved stats gathering tools (perhaps integration with nfsometer?) 70 to extend and make easier to use what is currently in /proc/fs/cifs/Stats 71 72n) Add support for claims based ACLs ("DAC") 73 74o) mount helper GUI (to simplify the various configuration options on mount) 75 76p) Expand support for witness protocol to allow for notification of share 77 move, and server network adapter changes. Currently only notifications by 78 the witness protocol for server move is supported by the Linux client. 79 80q) Allow mount.cifs to be more verbose in reporting errors with dialect 81 or unsupported feature errors. This would now be easier due to the 82 implementation of the new mount API. 83 84r) updating cifs documentation, and user guide. 85 86s) Addressing bugs found by running a broader set of xfstests in standard 87 file system xfstest suite. 88 89t) split cifs and smb3 support into separate modules so legacy (and less 90 secure) CIFS dialect can be disabled in environments that don't need it 91 and simplify the code. 92 93v) Additional testing of POSIX Extensions for SMB3.1.1 94 95w) Add support for additional strong encryption types, and additional spnego 96 authentication mechanisms (see MS-SMB2). GCM-256 is now partially implemented. 97 98x) Finish support for SMB3.1.1 compression 99 100Known Bugs 101========== 102 103See https://bugzilla.samba.org - search on product "CifsVFS" for 104current bug list. Also check http://bugzilla.kernel.org (Product = File System, Component = CIFS) 105 1061) existing symbolic links (Windows reparse points) are recognized but 107 can not be created remotely. They are implemented for Samba and those that 108 support the CIFS Unix extensions, although earlier versions of Samba 109 overly restrict the pathnames. 1102) follow_link and readdir code does not follow dfs junctions 111 but recognizes them 112 113Misc testing to do 114================== 1151) check out max path names and max path name components against various server 116 types. Try nested symlinks (8 deep). Return max path name in stat -f information 117 1182) Improve xfstest's cifs/smb3 enablement and adapt xfstests where needed to test 119 cifs/smb3 better 120 1213) Additional performance testing and optimization using iozone and similar - 122 there are some easy changes that can be done to parallelize sequential writes, 123 and when signing is disabled to request larger read sizes (larger than 124 negotiated size) and send larger write sizes to modern servers. 125 1264) More exhaustively test against less common servers 127 1285) Continue to extend the smb3 "buildbot" which does automated xfstesting 129 against Windows, Samba and Azure currently - to add additional tests and 130 to allow the buildbot to execute the tests faster. The URL for the 131 buildbot is: http://smb3-test-rhel-75.southcentralus.cloudapp.azure.com 132 1336) Address various coverity warnings (most are not bugs per-se, but 134 the more warnings are addressed, the easier it is to spot real 135 problems that static analyzers will point out in the future).