diff options
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/.gitignore | 1 | ||||
| -rw-r--r-- | Documentation/filesystems/Locking | 6 | ||||
| -rw-r--r-- | Documentation/filesystems/Makefile | 3 | ||||
| -rw-r--r-- | Documentation/filesystems/cifs/AUTHORS | 1 | ||||
| -rw-r--r-- | Documentation/filesystems/cifs/TODO | 97 | ||||
| -rw-r--r-- | Documentation/filesystems/nfs/Exporting | 38 | ||||
| -rw-r--r-- | Documentation/filesystems/nfs/nfs-rdma.txt | 16 | ||||
| -rw-r--r-- | Documentation/filesystems/seq_file.txt | 33 | ||||
| -rw-r--r-- | Documentation/filesystems/vfs.txt | 3 |
9 files changed, 111 insertions, 87 deletions
diff --git a/Documentation/filesystems/.gitignore b/Documentation/filesystems/.gitignore new file mode 100644 index 000000000000..31d6e426b6d4 --- /dev/null +++ b/Documentation/filesystems/.gitignore @@ -0,0 +1 @@ +dnotify_test diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index b18dd1779029..f1997e9da61f 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -349,7 +349,11 @@ prototypes: locking rules: inode->i_lock may block fl_copy_lock: yes no -fl_release_private: maybe no +fl_release_private: maybe maybe[1] + +[1]: ->fl_release_private for flock or POSIX locks is currently allowed +to block. Leases however can still be freed while the i_lock is held and +so fl_release_private called on a lease should not block. ----------------------- lock_manager_operations --------------------------- prototypes: diff --git a/Documentation/filesystems/Makefile b/Documentation/filesystems/Makefile index a5dd114da14f..13483d192ebb 100644 --- a/Documentation/filesystems/Makefile +++ b/Documentation/filesystems/Makefile @@ -1,5 +1,4 @@ -# kbuild trick to avoid linker error. Can be omitted if a module is built. -obj- := dummy.o +subdir-y := configfs # List of programs to build hostprogs-y := dnotify_test diff --git a/Documentation/filesystems/cifs/AUTHORS b/Documentation/filesystems/cifs/AUTHORS index ca4a67a0bb1e..c98800df677f 100644 --- a/Documentation/filesystems/cifs/AUTHORS +++ b/Documentation/filesystems/cifs/AUTHORS @@ -40,6 +40,7 @@ Gunter Kukkukk (testing and suggestions for support of old servers) Igor Mammedov (DFS support) Jeff Layton (many, many fixes, as well as great work on the cifs Kerberos code) Scott Lovenberg +Pavel Shilovsky (for great work adding SMB2 support, and various SMB3 features) Test case and Bug Report contributors ------------------------------------- diff --git a/Documentation/filesystems/cifs/TODO b/Documentation/filesystems/cifs/TODO index 355abcdcda98..066ffddc3964 100644 --- a/Documentation/filesystems/cifs/TODO +++ b/Documentation/filesystems/cifs/TODO @@ -1,4 +1,4 @@ -Version 1.53 May 20, 2008 +Version 2.03 August 1, 2014 A Partial List of Missing Features ================================== @@ -7,63 +7,49 @@ Contributions are welcome. There are plenty of opportunities for visible, important contributions to this module. Here is a partial list of the known problems and missing features: -a) Support for SecurityDescriptors(Windows/CIFS ACLs) for chmod/chgrp/chown -so that these operations can be supported to Windows servers +a) SMB3 (and SMB3.02) missing optional features: + - RDMA + - multichannel (started) + - directory leases (improved metadata caching) + - T10 copy offload (copy chunk is only mechanism supported) + - encrypted shares -b) Mapping POSIX ACLs (and eventually NFSv4 ACLs) to CIFS -SecurityDescriptors +b) improved sparse file support -c) Better pam/winbind integration (e.g. to handle uid mapping -better) - -d) Cleanup now unneeded SessSetup code in -fs/cifs/connect.c and add back in NTLMSSP code if any servers -need it - -e) fix NTLMv2 signing when two mounts with different users to same -server. - -f) Directory entry caching relies on a 1 second timer, rather than +c) Directory entry caching relies on a 1 second timer, rather than using FindNotify or equivalent. - (started) -g) quota support (needs minor kernel change since quota calls +d) quota support (needs minor kernel change since quota calls to make it to network filesystems or deviceless filesystems) -h) investigate sync behavior (including syncpage) and check -for proper behavior of intr/nointr - -i) improve support for very old servers (OS/2 and Win9x for example) +e) improve support for very old servers (OS/2 and Win9x for example) Including support for changing the time remotely (utimes command). -j) hook lower into the sockets api (as NFS/SunRPC does) to avoid the +f) hook lower into the sockets api (as NFS/SunRPC does) to avoid the extra copy in/out of the socket buffers in some cases. -k) Better optimize open (and pathbased setfilesize) to reduce the +g) Better optimize open (and pathbased setfilesize) to reduce the oplock breaks coming from windows srv. Piggyback identical file opens on top of each other by incrementing reference count rather than resending (helps reduce server resource utilization and avoid spurious oplock breaks). -l) Improve performance of readpages by sending more than one read -at a time when 8 pages or more are requested. In conjuntion -add support for async_cifs_readpages. - -m) Add support for storing symlink info to Windows servers +h) Add support for storing symlink info to Windows servers in the Extended Attribute format their SFU clients would recognize. -n) Finish fcntl D_NOTIFY support so kde and gnome file list windows +i) Finish inotify support so kde and gnome file list windows will autorefresh (partially complete by Asser). Needs minor kernel vfs change to support removing D_NOTIFY on a file. -o) Add GUI tool to configure /proc/fs/cifs settings and for display of +j) Add GUI tool to configure /proc/fs/cifs settings and for display of the CIFS statistics (started) -p) implement support for security and trusted categories of xattrs +k) implement support for security and trusted categories of xattrs (requires minor protocol extension) to enable better support for SELINUX -q) Implement O_DIRECT flag on open (already supported on mount) +l) Implement O_DIRECT flag on open (already supported on mount) -r) Create UID mapping facility so server UIDs can be mapped on a per +m) Create UID mapping facility so server UIDs can be mapped on a per mount or a per server basis to client UIDs or nobody if no mapping exists. This is helpful when Unix extensions are negotiated to allow better permission checking when UIDs differ on the server @@ -71,28 +57,29 @@ and client. Add new protocol request to the CIFS protocol standard for asking the server for the corresponding name of a particular uid. -s) Add support for CIFS Unix and also the newer POSIX extensions to the -server side for Samba 4. +n) DOS attrs - returned as pseudo-xattr in Samba format (check VFAT and NTFS for this too) + +o) mount check for unmatched uids -t) In support for OS/2 (LANMAN 1.2 and LANMAN2.1 based SMB servers) -need to add ability to set time to server (utimes command) +p) Add support for new vfs entry point for fallocate -u) DOS attrs - returned as pseudo-xattr in Samba format (check VFAT and NTFS for this too) +q) Add tools to take advantage of cifs/smb3 specific ioctls and features +such as "CopyChunk" (fast server side file copy) -v) mount check for unmatched uids +r) encrypted file support -w) Add support for new vfs entry point for fallocate +s) improved stats gathering, tools (perhaps integration with nfsometer?) -x) Fix Samba 3 server to handle Linux kernel aio so dbench with lots of -processes can proceed better in parallel (on the server) +t) allow setting more NTFS/SMB3 file attributes remotely (currently limited to compressed +file attribute via chflags) -y) Fix Samba 3 to handle reads/writes over 127K (and remove the cifs mount -restriction of wsize max being 127K) +u) mount helper GUI (to simplify the various configuration options on mount) -KNOWN BUGS (updated April 24, 2007) + +KNOWN BUGS ==================================== See http://bugzilla.samba.org - search on product "CifsVFS" for -current bug list. +current bug list. Also check http://bugzilla.kernel.org (Product = File System, Component = CIFS) 1) existing symbolic links (Windows reparse points) are recognized but can not be created remotely. They are implemented for Samba and those that @@ -100,30 +87,18 @@ support the CIFS Unix extensions, although earlier versions of Samba overly restrict the pathnames. 2) follow_link and readdir code does not follow dfs junctions but recognizes them -3) create of new files to FAT partitions on Windows servers can -succeed but still return access denied (appears to be Windows -server not cifs client problem) and has not been reproduced recently. -NTFS partitions do not have this problem. -4) Unix/POSIX capabilities are reset after reconnection, and affect -a few fields in the tree connection but we do do not know which -superblocks to apply these changes to. We should probably walk -the list of superblocks to set these. Also need to check the -flags on the second mount to the same share, and see if we -can do the same trick that NFS does to remount duplicate shares. Misc testing to do ================== 1) check out max path names and max path name components against various server types. Try nested symlinks (8 deep). Return max path name in stat -f information -2) Modify file portion of ltp so it can run against a mounted network -share and run it against cifs vfs in automated fashion. +2) Improve xfstest's cifs enablement and adapt xfstests where needed to test +cifs better 3) Additional performance testing and optimization using iozone and similar - there are some easy changes that can be done to parallelize sequential writes, and when signing is disabled to request larger read sizes (larger than negotiated size) and send larger write sizes to modern servers. -4) More exhaustively test against less common servers. More testing -against Windows 9x, Windows ME servers. - +4) More exhaustively test against less common servers diff --git a/Documentation/filesystems/nfs/Exporting b/Documentation/filesystems/nfs/Exporting index e543b1a619cc..c8f036a9b13f 100644 --- a/Documentation/filesystems/nfs/Exporting +++ b/Documentation/filesystems/nfs/Exporting @@ -66,23 +66,31 @@ b/ A per-superblock list "s_anon" of dentries which are the roots of c/ Helper routines to allocate anonymous dentries, and to help attach loose directory dentries at lookup time. They are: - d_alloc_anon(inode) will return a dentry for the given inode. + d_obtain_alias(inode) will return a dentry for the given inode. If the inode already has a dentry, one of those is returned. If it doesn't, a new anonymous (IS_ROOT and DCACHE_DISCONNECTED) dentry is allocated and attached. In the case of a directory, care is taken that only one dentry can ever be attached. - d_splice_alias(inode, dentry) will make sure that there is a - dentry with the same name and parent as the given dentry, and - which refers to the given inode. - If the inode is a directory and already has a dentry, then that - dentry is d_moved over the given dentry. - If the passed dentry gets attached, care is taken that this is - mutually exclusive to a d_alloc_anon operation. - If the passed dentry is used, NULL is returned, else the used - dentry is returned. This corresponds to the calling pattern of - ->lookup. - + d_splice_alias(inode, dentry) or d_materialise_unique(dentry, inode) + will introduce a new dentry into the tree; either the passed-in + dentry or a preexisting alias for the given inode (such as an + anonymous one created by d_obtain_alias), if appropriate. The two + functions differ in their handling of directories with preexisting + aliases: + d_splice_alias will use any existing IS_ROOT dentry, but it will + return -EIO rather than try to move a dentry with a different + parent. This is appropriate for local filesystems, which + should never see such an alias unless the filesystem is + corrupted somehow (for example, if two on-disk directory + entries refer to the same directory.) + d_materialise_unique will attempt to move any dentry. This is + appropriate for distributed filesystems, where finding a + directory other than where we last cached it may be a normal + consequence of concurrent operations on other hosts. + Both functions return NULL when the passed-in dentry is used, + following the calling convention of ->lookup. + Filesystem Issues ----------------- @@ -120,12 +128,12 @@ struct which has the following members: fh_to_dentry (mandatory) Given a filehandle fragment, this should find the implied object and - create a dentry for it (possibly with d_alloc_anon). + create a dentry for it (possibly with d_obtain_alias). fh_to_parent (optional but strongly recommended) Given a filehandle fragment, this should find the parent of the - implied object and create a dentry for it (possibly with d_alloc_anon). - May fail if the filehandle fragment is too small. + implied object and create a dentry for it (possibly with + d_obtain_alias). May fail if the filehandle fragment is too small. get_parent (optional but strongly recommended) When given a dentry for a directory, this should return a dentry for diff --git a/Documentation/filesystems/nfs/nfs-rdma.txt b/Documentation/filesystems/nfs/nfs-rdma.txt index e386f7e4bcee..724043858b08 100644 --- a/Documentation/filesystems/nfs/nfs-rdma.txt +++ b/Documentation/filesystems/nfs/nfs-rdma.txt @@ -138,9 +138,9 @@ Installation - Build, install, reboot The NFS/RDMA code will be enabled automatically if NFS and RDMA - are turned on. The NFS/RDMA client and server are configured via the hidden - SUNRPC_XPRT_RDMA config option that depends on SUNRPC and INFINIBAND. The - value of SUNRPC_XPRT_RDMA will be: + are turned on. The NFS/RDMA client and server are configured via the + SUNRPC_XPRT_RDMA_CLIENT and SUNRPC_XPRT_RDMA_SERVER config options that both + depend on SUNRPC and INFINIBAND. The default value of both options will be: - N if either SUNRPC or INFINIBAND are N, in this case the NFS/RDMA client and server will not be built @@ -235,8 +235,9 @@ NFS/RDMA Setup - Start the NFS server - If the NFS/RDMA server was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in - kernel config), load the RDMA transport module: + If the NFS/RDMA server was built as a module + (CONFIG_SUNRPC_XPRT_RDMA_SERVER=m in kernel config), load the RDMA + transport module: $ modprobe svcrdma @@ -255,8 +256,9 @@ NFS/RDMA Setup - On the client system - If the NFS/RDMA client was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in - kernel config), load the RDMA client module: + If the NFS/RDMA client was built as a module + (CONFIG_SUNRPC_XPRT_RDMA_CLIENT=m in kernel config), load the RDMA client + module: $ modprobe xprtrdma.ko diff --git a/Documentation/filesystems/seq_file.txt b/Documentation/filesystems/seq_file.txt index 1fe0ccb1af55..8ea3e90ace07 100644 --- a/Documentation/filesystems/seq_file.txt +++ b/Documentation/filesystems/seq_file.txt @@ -235,6 +235,39 @@ be used for more than one file, you can store an arbitrary pointer in the private field of the seq_file structure; that value can then be retrieved by the iterator functions. +There is also a wrapper function to seq_open() called seq_open_private(). It +kmallocs a zero filled block of memory and stores a pointer to it in the +private field of the seq_file structure, returning 0 on success. The +block size is specified in a third parameter to the function, e.g.: + + static int ct_open(struct inode *inode, struct file *file) + { + return seq_open_private(file, &ct_seq_ops, + sizeof(struct mystruct)); + } + +There is also a variant function, __seq_open_private(), which is functionally +identical except that, if successful, it returns the pointer to the allocated +memory block, allowing further initialisation e.g.: + + static int ct_open(struct inode *inode, struct file *file) + { + struct mystruct *p = + __seq_open_private(file, &ct_seq_ops, sizeof(*p)); + + if (!p) + return -ENOMEM; + + p->foo = bar; /* initialize my stuff */ + ... + p->baz = true; + + return 0; + } + +A corresponding close function, seq_release_private() is available which +frees the memory allocated in the corresponding open. + The other operations of interest - read(), llseek(), and release() - are all implemented by the seq_file code itself. So a virtual file's file_operations structure will look like: diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index a1d0d7a30165..61d65cc65c54 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -1053,7 +1053,8 @@ struct dentry_operations { If the 'rcu_walk' parameter is true, then the caller is doing a pathwalk in RCU-walk mode. Sleeping is not permitted in this mode, and the caller can be asked to leave it and call again by returning - -ECHILD. + -ECHILD. -EISDIR may also be returned to tell pathwalk to + ignore d_automount or any mounts. This function is only used if DCACHE_MANAGE_TRANSIT is set on the dentry being transited from. |