1==== 2TODO 3==== 4 5As of 6.7 kernel. See https://wiki.samba.org/index.php/LinuxCIFSKernel 6for list of features added by release 7 8A Partial List of Missing Features 9================================== 10 11Contributions are welcome. There are plenty of opportunities 12for visible, important contributions to this module. Here 13is a partial list of the known problems and missing features: 14 15a) SMB3 (and SMB3.1.1) missing optional features: 16 multichannel performance optimizations, algorithmic channel selection, 17 directory leases optimizations, 18 support for faster packet signing (GMAC), 19 support for compression over the network, 20 T10 copy offload ie "ODX" (copy chunk, and "Duplicate Extents" ioctl 21 are currently the only two server side copy mechanisms supported) 22 23b) Better optimized compounding and error handling for sparse file support, 24 perhaps addition of new optional SMB3.1.1 fsctls to make collapse range 25 and insert range more atomic 26 27c) Support for SMB3.1.1 over QUIC (and perhaps other socket based protocols 28 like SCTP) 29 30d) quota support (needs minor kernel change since quota calls otherwise 31 won't make it to network filesystems or deviceless filesystems). 32 33e) Additional use cases can be optimized to use "compounding" (e.g. 34 open/query/close and open/setinfo/close) to reduce the number of 35 roundtrips to the server and improve performance. Various cases 36 (stat, statfs, create, unlink, mkdir, xattrs) already have been improved by 37 using compounding but more can be done. In addition we could 38 significantly reduce redundant opens by using deferred close (with 39 handle caching leases) and better using reference counters on file 40 handles. 41 42f) Finish inotify support so kde and gnome file list windows 43 will autorefresh (partially complete by Asser). Needs minor kernel 44 vfs change to support removing D_NOTIFY on a file. 45 46g) Add GUI tool to configure /proc/fs/cifs settings and for display of 47 the CIFS statistics (started) 48 49h) implement support for security and trusted categories of xattrs 50 (requires minor protocol extension) to enable better support for SELINUX 51 52i) Add support for tree connect contexts (see MS-SMB2) a new SMB3.1.1 protocol 53 feature (may be especially useful for virtualization). 54 55j) Create UID mapping facility so server UIDs can be mapped on a per 56 mount or a per server basis to client UIDs or nobody if no mapping 57 exists. Also better integration with winbind for resolving SID owners 58 59k) Add tools to take advantage of more smb3 specific ioctls and features 60 (passthrough ioctl/fsctl is now implemented in cifs.ko to allow 61 sending various SMB3 fsctls and query info and set info calls 62 directly from user space) Add tools to make setting various non-POSIX 63 metadata attributes easier from tools (e.g. extending what was done 64 in smb-info tool). 65 66l) encrypted file support (currently the attribute showing the file is 67 encrypted on the server is reported, but changing the attribute is not 68 supported). 69 70m) improved stats gathering tools (perhaps integration with nfsometer?) 71 to extend and make easier to use what is currently in /proc/fs/cifs/Stats 72 73n) Add support for claims based ACLs ("DAC") 74 75o) mount helper GUI (to simplify the various configuration options on mount) 76 77p) Expand support for witness protocol to allow for notification of share 78 move, and server network adapter changes. Currently only notifications by 79 the witness protocol for server move is supported by the Linux client. 80 81q) Allow mount.cifs to be more verbose in reporting errors with dialect 82 or unsupported feature errors. This would now be easier due to the 83 implementation of the new mount API. 84 85r) updating cifs documentation, and user guide. 86 87s) Addressing bugs found by running a broader set of xfstests in standard 88 file system xfstest suite. 89 90t) split cifs and smb3 support into separate modules so legacy (and less 91 secure) CIFS dialect can be disabled in environments that don't need it 92 and simplify the code. 93 94v) Additional testing of POSIX Extensions for SMB3.1.1 95 96w) Support for the Mac SMB3.1.1 extensions to improve interop with Apple servers 97 98x) Support for additional authentication options (e.g. IAKERB, peer-to-peer 99 Kerberos, SCRAM and others supported by existing servers) 100 101y) Improved tracing, more eBPF trace points, better scripts for performance 102 analysis 103 104Known Bugs 105========== 106 107See https://bugzilla.samba.org - search on product "CifsVFS" for 108current bug list. Also check http://bugzilla.kernel.org (Product = File System, Component = CIFS) 109and xfstest results e.g. https://wiki.samba.org/index.php/Xfstest-results-smb3 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