diff options
Diffstat (limited to 'Documentation/filesystems')
| -rw-r--r-- | Documentation/filesystems/Locking | 3 | ||||
| -rw-r--r-- | Documentation/filesystems/nfs-rdma.txt | 256 | ||||
| -rw-r--r-- | Documentation/filesystems/proc.txt | 38 | ||||
| -rw-r--r-- | Documentation/filesystems/seq_file.txt | 19 | ||||
| -rw-r--r-- | Documentation/filesystems/sysfs.txt | 9 | ||||
| -rw-r--r-- | Documentation/filesystems/tmpfs.txt | 12 | ||||
| -rw-r--r-- | Documentation/filesystems/vfat.txt | 15 | ||||
| -rw-r--r-- | Documentation/filesystems/xfs.txt | 15 |
8 files changed, 350 insertions, 17 deletions
diff --git a/Documentation/filesystems/Locking b/Documentation/filesystems/Locking index 42d4b30b104..c2992bc54f2 100644 --- a/Documentation/filesystems/Locking +++ b/Documentation/filesystems/Locking @@ -511,7 +511,6 @@ prototypes: void (*open)(struct vm_area_struct*); void (*close)(struct vm_area_struct*); int (*fault)(struct vm_area_struct*, struct vm_fault *); - struct page *(*nopage)(struct vm_area_struct*, unsigned long, int *); int (*page_mkwrite)(struct vm_area_struct *, struct page *); locking rules: @@ -519,7 +518,6 @@ locking rules: open: no yes close: no yes fault: no yes -nopage: no yes page_mkwrite: no yes no ->page_mkwrite() is called when a previously read-only page is @@ -537,4 +535,3 @@ NULL. ipc/shm.c::shm_delete() - may need BKL. ->read() and ->write() in many drivers are (probably) missing BKL. -drivers/sgi/char/graphics.c::sgi_graphics_nopage() - may need BKL. diff --git a/Documentation/filesystems/nfs-rdma.txt b/Documentation/filesystems/nfs-rdma.txt new file mode 100644 index 00000000000..d0ec45ae4e7 --- /dev/null +++ b/Documentation/filesystems/nfs-rdma.txt @@ -0,0 +1,256 @@ +################################################################################ +# # +# NFS/RDMA README # +# # +################################################################################ + + Author: NetApp and Open Grid Computing + Date: April 15, 2008 + +Table of Contents +~~~~~~~~~~~~~~~~~ + - Overview + - Getting Help + - Installation + - Check RDMA and NFS Setup + - NFS/RDMA Setup + +Overview +~~~~~~~~ + + This document describes how to install and setup the Linux NFS/RDMA client + and server software. + + The NFS/RDMA client was first included in Linux 2.6.24. The NFS/RDMA server + was first included in the following release, Linux 2.6.25. + + In our testing, we have obtained excellent performance results (full 10Gbit + wire bandwidth at minimal client CPU) under many workloads. The code passes + the full Connectathon test suite and operates over both Infiniband and iWARP + RDMA adapters. + +Getting Help +~~~~~~~~~~~~ + + If you get stuck, you can ask questions on the + + nfs-rdma-devel@lists.sourceforge.net + + mailing list. + +Installation +~~~~~~~~~~~~ + + These instructions are a step by step guide to building a machine for + use with NFS/RDMA. + + - Install an RDMA device + + Any device supported by the drivers in drivers/infiniband/hw is acceptable. + + Testing has been performed using several Mellanox-based IB cards, the + Ammasso AMS1100 iWARP adapter, and the Chelsio cxgb3 iWARP adapter. + + - Install a Linux distribution and tools + + The first kernel release to contain both the NFS/RDMA client and server was + Linux 2.6.25 Therefore, a distribution compatible with this and subsequent + Linux kernel release should be installed. + + The procedures described in this document have been tested with + distributions from Red Hat's Fedora Project (http://fedora.redhat.com/). + + - Install nfs-utils-1.1.1 or greater on the client + + An NFS/RDMA mount point can only be obtained by using the mount.nfs + command in nfs-utils-1.1.1 or greater. To see which version of mount.nfs + you are using, type: + + > /sbin/mount.nfs -V + + If the version is less than 1.1.1 or the command does not exist, + then you will need to install the latest version of nfs-utils. + + Download the latest package from: + + http://www.kernel.org/pub/linux/utils/nfs + + Uncompress the package and follow the installation instructions. + + If you will not be using GSS and NFSv4, the installation process + can be simplified by disabling these features when running configure: + + > ./configure --disable-gss --disable-nfsv4 + + For more information on this see the package's README and INSTALL files. + + After building the nfs-utils package, there will be a mount.nfs binary in + the utils/mount directory. This binary can be used to initiate NFS v2, v3, + or v4 mounts. To initiate a v4 mount, the binary must be called mount.nfs4. + The standard technique is to create a symlink called mount.nfs4 to mount.nfs. + + NOTE: mount.nfs and therefore nfs-utils-1.1.1 or greater is only needed + on the NFS client machine. You do not need this specific version of + nfs-utils on the server. Furthermore, only the mount.nfs command from + nfs-utils-1.1.1 is needed on the client. + + - Install a Linux kernel with NFS/RDMA + + The NFS/RDMA client and server are both included in the mainline Linux + kernel version 2.6.25 and later. This and other versions of the 2.6 Linux + kernel can be found at: + + ftp://ftp.kernel.org/pub/linux/kernel/v2.6/ + + Download the sources and place them in an appropriate location. + + - Configure the RDMA stack + + Make sure your kernel configuration has RDMA support enabled. Under + Device Drivers -> InfiniBand support, update the kernel configuration + to enable InfiniBand support [NOTE: the option name is misleading. Enabling + InfiniBand support is required for all RDMA devices (IB, iWARP, etc.)]. + + Enable the appropriate IB HCA support (mlx4, mthca, ehca, ipath, etc.) or + iWARP adapter support (amso, cxgb3, etc.). + + If you are using InfiniBand, be sure to enable IP-over-InfiniBand support. + + - Configure the NFS client and server + + Your kernel configuration must also have NFS file system support and/or + NFS server support enabled. These and other NFS related configuration + options can be found under File Systems -> Network File Systems. + + - 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: + + - N if either SUNRPC or INFINIBAND are N, in this case the NFS/RDMA client + and server will not be built + - M if both SUNRPC and INFINIBAND are on (M or Y) and at least one is M, + in this case the NFS/RDMA client and server will be built as modules + - Y if both SUNRPC and INFINIBAND are Y, in this case the NFS/RDMA client + and server will be built into the kernel + + Therefore, if you have followed the steps above and turned no NFS and RDMA, + the NFS/RDMA client and server will be built. + + Build a new kernel, install it, boot it. + +Check RDMA and NFS Setup +~~~~~~~~~~~~~~~~~~~~~~~~ + + Before configuring the NFS/RDMA software, it is a good idea to test + your new kernel to ensure that the kernel is working correctly. + In particular, it is a good idea to verify that the RDMA stack + is functioning as expected and standard NFS over TCP/IP and/or UDP/IP + is working properly. + + - Check RDMA Setup + + If you built the RDMA components as modules, load them at + this time. For example, if you are using a Mellanox Tavor/Sinai/Arbel + card: + + > modprobe ib_mthca + > modprobe ib_ipoib + + If you are using InfiniBand, make sure there is a Subnet Manager (SM) + running on the network. If your IB switch has an embedded SM, you can + use it. Otherwise, you will need to run an SM, such as OpenSM, on one + of your end nodes. + + If an SM is running on your network, you should see the following: + + > cat /sys/class/infiniband/driverX/ports/1/state + 4: ACTIVE + + where driverX is mthca0, ipath5, ehca3, etc. + + To further test the InfiniBand software stack, use IPoIB (this + assumes you have two IB hosts named host1 and host2): + + host1> ifconfig ib0 a.b.c.x + host2> ifconfig ib0 a.b.c.y + host1> ping a.b.c.y + host2> ping a.b.c.x + + For other device types, follow the appropriate procedures. + + - Check NFS Setup + + For the NFS components enabled above (client and/or server), + test their functionality over standard Ethernet using TCP/IP or UDP/IP. + +NFS/RDMA Setup +~~~~~~~~~~~~~~ + + We recommend that you use two machines, one to act as the client and + one to act as the server. + + One time configuration: + + - On the server system, configure the /etc/exports file and + start the NFS/RDMA server. + + Exports entries with the following formats have been tested: + + /vol0 192.168.0.47(fsid=0,rw,async,insecure,no_root_squash) + /vol0 192.168.0.0/255.255.255.0(fsid=0,rw,async,insecure,no_root_squash) + + The IP address(es) is(are) the client's IPoIB address for an InfiniBand HCA or the + cleint's iWARP address(es) for an RNIC. + + NOTE: The "insecure" option must be used because the NFS/RDMA client does not + use a reserved port. + + Each time a machine boots: + + - Load and configure the RDMA drivers + + For InfiniBand using a Mellanox adapter: + + > modprobe ib_mthca + > modprobe ib_ipoib + > ifconfig ib0 a.b.c.d + + NOTE: use unique addresses for the client and server + + - 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: + + > modprobe svcrdma + + Regardless of how the server was built (module or built-in), start the server: + + > /etc/init.d/nfs start + + or + + > service nfs start + + Instruct the server to listen on the RDMA transport: + + > echo rdma 2050 > /proc/fs/nfsd/portlist + + - 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: + + > modprobe xprtrdma.ko + + Regardless of how the client was built (module or built-in), issue the mount.nfs command: + + > /path/to/your/mount.nfs <IPoIB-server-name-or-address>:/<export> /mnt -i -o rdma,port=2050 + + To verify that the mount is using RDMA, run "cat /proc/mounts" and check the + "proto" field for the given mount. + + Congratulations! You're using NFS/RDMA! diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 518ebe609e2..2a99116edc4 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -43,6 +43,7 @@ Table of Contents 2.13 /proc/<pid>/oom_score - Display current oom-killer score 2.14 /proc/<pid>/io - Display the IO accounting fields 2.15 /proc/<pid>/coredump_filter - Core dump filtering settings + 2.16 /proc/<pid>/mountinfo - Information about mounts ------------------------------------------------------------------------------ Preface @@ -2348,4 +2349,41 @@ For example: $ echo 0x7 > /proc/self/coredump_filter $ ./some_program +2.16 /proc/<pid>/mountinfo - Information about mounts +-------------------------------------------------------- + +This file contains lines of the form: + +36 35 98:0 /mnt1 /mnt2 rw,noatime master:1 - ext3 /dev/root rw,errors=continue +(1)(2)(3) (4) (5) (6) (7) (8) (9) (10) (11) + +(1) mount ID: unique identifier of the mount (may be reused after umount) +(2) parent ID: ID of parent (or of self for the top of the mount tree) +(3) major:minor: value of st_dev for files on filesystem +(4) root: root of the mount within the filesystem +(5) mount point: mount point relative to the process's root +(6) mount options: per mount options +(7) optional fields: zero or more fields of the form "tag[:value]" +(8) separator: marks the end of the optional fields +(9) filesystem type: name of filesystem of the form "type[.subtype]" +(10) mount source: filesystem specific information or "none" +(11) super options: per super block options + +Parsers should ignore all unrecognised optional fields. Currently the +possible optional fields are: + +shared:X mount is shared in peer group X +master:X mount is slave to peer group X +propagate_from:X mount is slave and receives propagation from peer group X (*) +unbindable mount is unbindable + +(*) X is the closest dominant peer group under the process's root. If +X is the immediate master of the mount, or if there's no dominant peer +group under the same root, then only the "master:X" field is present +and not the "propagate_from:X" field. + +For more information on mount propagation see: + + Documentation/filesystems/sharedsubtree.txt + ------------------------------------------------------------------------------ diff --git a/Documentation/filesystems/seq_file.txt b/Documentation/filesystems/seq_file.txt index 7fb8e6dc62b..b843743aa0b 100644 --- a/Documentation/filesystems/seq_file.txt +++ b/Documentation/filesystems/seq_file.txt @@ -122,8 +122,7 @@ stop() is the place to free it. } Finally, the show() function should format the object currently pointed to -by the iterator for output. It should return zero, or an error code if -something goes wrong. The example module's show() function is: +by the iterator for output. The example module's show() function is: static int ct_seq_show(struct seq_file *s, void *v) { @@ -132,6 +131,12 @@ something goes wrong. The example module's show() function is: return 0; } +If all is well, the show() function should return zero. A negative error +code in the usual manner indicates that something went wrong; it will be +passed back to user space. This function can also return SEQ_SKIP, which +causes the current item to be skipped; if the show() function has already +generated output before returning SEQ_SKIP, that output will be dropped. + We will look at seq_printf() in a moment. But first, the definition of the seq_file iterator is finished by creating a seq_operations structure with the four functions we have just defined: @@ -182,12 +187,18 @@ The first two output a single character and a string, just like one would expect. seq_escape() is like seq_puts(), except that any character in s which is in the string esc will be represented in octal form in the output. -There is also a function for printing filenames: +There is also a pair of functions for printing filenames: int seq_path(struct seq_file *m, struct path *path, char *esc); + int seq_path_root(struct seq_file *m, struct path *path, + struct path *root, char *esc) Here, path indicates the file of interest, and esc is a set of characters -which should be escaped in the output. +which should be escaped in the output. A call to seq_path() will output +the path relative to the current process's filesystem root. If a different +root is desired, it can be used with seq_path_root(). Note that, if it +turns out that path cannot be reached from root, the value of root will be +changed in seq_file_root() to a root which *does* work. Making it all work diff --git a/Documentation/filesystems/sysfs.txt b/Documentation/filesystems/sysfs.txt index 4598ef7b622..7f27b8f840d 100644 --- a/Documentation/filesystems/sysfs.txt +++ b/Documentation/filesystems/sysfs.txt @@ -176,8 +176,10 @@ implementations: Recall that an attribute should only be exporting one value, or an array of similar values, so this shouldn't be that expensive. - This allows userspace to do partial reads and seeks arbitrarily over - the entire file at will. + This allows userspace to do partial reads and forward seeks + arbitrarily over the entire file at will. If userspace seeks back to + zero or does a pread(2) with an offset of '0' the show() method will + be called again, rearmed, to fill the buffer. - On write(2), sysfs expects the entire buffer to be passed during the first write. Sysfs then passes the entire buffer to the store() @@ -192,6 +194,9 @@ implementations: Other notes: +- Writing causes the show() method to be rearmed regardless of current + file position. + - The buffer will always be PAGE_SIZE bytes in length. On i386, this is 4096. diff --git a/Documentation/filesystems/tmpfs.txt b/Documentation/filesystems/tmpfs.txt index 145e4408635..222437efd75 100644 --- a/Documentation/filesystems/tmpfs.txt +++ b/Documentation/filesystems/tmpfs.txt @@ -92,6 +92,18 @@ NodeList format is a comma-separated list of decimal numbers and ranges, a range being two hyphen-separated decimal numbers, the smallest and largest node numbers in the range. For example, mpol=bind:0-3,5,7,9-15 +NUMA memory allocation policies have optional flags that can be used in +conjunction with their modes. These optional flags can be specified +when tmpfs is mounted by appending them to the mode before the NodeList. +See Documentation/vm/numa_memory_policy.txt for a list of all available +memory allocation policy mode flags. + + =static is equivalent to MPOL_F_STATIC_NODES + =relative is equivalent to MPOL_F_RELATIVE_NODES + +For example, mpol=bind=static:NodeList, is the equivalent of an +allocation policy of MPOL_BIND | MPOL_F_STATIC_NODES. + Note that trying to mount a tmpfs with an mpol option will fail if the running kernel does not support NUMA; and will fail if its nodelist specifies a node which is not online. If your system relies on that diff --git a/Documentation/filesystems/vfat.txt b/Documentation/filesystems/vfat.txt index fcc123ffa25..2d5e1e582e1 100644 --- a/Documentation/filesystems/vfat.txt +++ b/Documentation/filesystems/vfat.txt @@ -17,6 +17,21 @@ dmask=### -- The permission mask for the directory. fmask=### -- The permission mask for files. The default is the umask of current process. +allow_utime=### -- This option controls the permission check of mtime/atime. + + 20 - If current process is in group of file's group ID, + you can change timestamp. + 2 - Other users can change timestamp. + + The default is set from `dmask' option. (If the directory is + writable, utime(2) is also allowed. I.e. ~dmask & 022) + + Normally utime(2) checks current process is owner of + the file, or it has CAP_FOWNER capability. But FAT + filesystem doesn't have uid/gid on disk, so normal + check is too unflexible. With this option you can + relax it. + codepage=### -- Sets the codepage number for converting to shortname characters on FAT filesystem. By default, FAT_DEFAULT_CODEPAGE setting is used. diff --git a/Documentation/filesystems/xfs.txt b/Documentation/filesystems/xfs.txt index 74aeb142ae5..0a1668ba260 100644 --- a/Documentation/filesystems/xfs.txt +++ b/Documentation/filesystems/xfs.txt @@ -52,16 +52,15 @@ When mounting an XFS filesystem, the following options are accepted. and also gets the setgid bit set if it is a directory itself. ihashsize=value - Sets the number of hash buckets available for hashing the - in-memory inodes of the specified mount point. If a value - of zero is used, the value selected by the default algorithm - will be displayed in /proc/mounts. + In memory inode hashes have been removed, so this option has + no function as of August 2007. Option is deprecated. ikeep/noikeep - When inode clusters are emptied of inodes, keep them around - on the disk (ikeep) - this is the traditional XFS behaviour - and is still the default for now. Using the noikeep option, - inode clusters are returned to the free space pool. + When ikeep is specified, XFS does not delete empty inode clusters + and keeps them around on disk. ikeep is the traditional XFS + behaviour. When noikeep is specified, empty inode clusters + are returned to the free space pool. The default is noikeep for + non-DMAPI mounts, while ikeep is the default when DMAPI is in use. inode64 Indicates that XFS is allowed to create inodes at any location |