aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/filesystems
diff options
context:
space:
mode:
authorJiri Kosina <jkosina@suse.cz>2010-04-22 20:08:44 -0400
committerJiri Kosina <jkosina@suse.cz>2010-04-22 20:08:44 -0400
commit6c9468e9eb1252eaefd94ce7f06e1be9b0b641b1 (patch)
tree797676a336b050bfa1ef879377c07e541b9075d6 /Documentation/filesystems
parent4cb3ca7cd7e2cae8d1daf5345ec99a1e8502cf3f (diff)
parentc81eddb0e3728661d1585fbc564449c94165cc36 (diff)
Merge branch 'master' into for-next
Diffstat (limited to 'Documentation/filesystems')
-rw-r--r--Documentation/filesystems/00-INDEX2
-rw-r--r--Documentation/filesystems/9p.txt18
-rw-r--r--Documentation/filesystems/ceph.txt140
-rw-r--r--Documentation/filesystems/tmpfs.txt6
4 files changed, 163 insertions, 3 deletions
diff --git a/Documentation/filesystems/00-INDEX b/Documentation/filesystems/00-INDEX
index 3bae418c6ad3..4303614b5add 100644
--- a/Documentation/filesystems/00-INDEX
+++ b/Documentation/filesystems/00-INDEX
@@ -16,6 +16,8 @@ befs.txt
16 - information about the BeOS filesystem for Linux. 16 - information about the BeOS filesystem for Linux.
17bfs.txt 17bfs.txt
18 - info for the SCO UnixWare Boot Filesystem (BFS). 18 - info for the SCO UnixWare Boot Filesystem (BFS).
19ceph.txt
20 - info for the Ceph Distributed File System
19cifs.txt 21cifs.txt
20 - description of the CIFS filesystem. 22 - description of the CIFS filesystem.
21coda.txt 23coda.txt
diff --git a/Documentation/filesystems/9p.txt b/Documentation/filesystems/9p.txt
index 57e0b80a5274..c0236e753bc8 100644
--- a/Documentation/filesystems/9p.txt
+++ b/Documentation/filesystems/9p.txt
@@ -37,6 +37,15 @@ For Plan 9 From User Space applications (http://swtch.com/plan9)
37 37
38 mount -t 9p `namespace`/acme /mnt/9 -o trans=unix,uname=$USER 38 mount -t 9p `namespace`/acme /mnt/9 -o trans=unix,uname=$USER
39 39
40For server running on QEMU host with virtio transport:
41
42 mount -t 9p -o trans=virtio <mount_tag> /mnt/9
43
44where mount_tag is the tag associated by the server to each of the exported
45mount points. Each 9P export is seen by the client as a virtio device with an
46associated "mount_tag" property. Available mount tags can be
47seen by reading /sys/bus/virtio/drivers/9pnet_virtio/virtio<n>/mount_tag files.
48
40OPTIONS 49OPTIONS
41======= 50=======
42 51
@@ -47,7 +56,7 @@ OPTIONS
47 fd - used passed file descriptors for connection 56 fd - used passed file descriptors for connection
48 (see rfdno and wfdno) 57 (see rfdno and wfdno)
49 virtio - connect to the next virtio channel available 58 virtio - connect to the next virtio channel available
50 (from lguest or KVM with trans_virtio module) 59 (from QEMU with trans_virtio module)
51 rdma - connect to a specified RDMA channel 60 rdma - connect to a specified RDMA channel
52 61
53 uname=name user name to attempt mount as on the remote server. The 62 uname=name user name to attempt mount as on the remote server. The
@@ -85,7 +94,12 @@ OPTIONS
85 94
86 port=n port to connect to on the remote server 95 port=n port to connect to on the remote server
87 96
88 noextend force legacy mode (no 9p2000.u semantics) 97 noextend force legacy mode (no 9p2000.u or 9p2000.L semantics)
98
99 version=name Select 9P protocol version. Valid options are:
100 9p2000 - Legacy mode (same as noextend)
101 9p2000.u - Use 9P2000.u protocol
102 9p2000.L - Use 9P2000.L protocol
89 103
90 dfltuid attempt to mount as a particular uid 104 dfltuid attempt to mount as a particular uid
91 105
diff --git a/Documentation/filesystems/ceph.txt b/Documentation/filesystems/ceph.txt
new file mode 100644
index 000000000000..0660c9f5deef
--- /dev/null
+++ b/Documentation/filesystems/ceph.txt
@@ -0,0 +1,140 @@
1Ceph Distributed File System
2============================
3
4Ceph is a distributed network file system designed to provide good
5performance, reliability, and scalability.
6
7Basic features include:
8
9 * POSIX semantics
10 * Seamless scaling from 1 to many thousands of nodes
11 * High availability and reliability. No single point of failure.
12 * N-way replication of data across storage nodes
13 * Fast recovery from node failures
14 * Automatic rebalancing of data on node addition/removal
15 * Easy deployment: most FS components are userspace daemons
16
17Also,
18 * Flexible snapshots (on any directory)
19 * Recursive accounting (nested files, directories, bytes)
20
21In contrast to cluster filesystems like GFS, OCFS2, and GPFS that rely
22on symmetric access by all clients to shared block devices, Ceph
23separates data and metadata management into independent server
24clusters, similar to Lustre. Unlike Lustre, however, metadata and
25storage nodes run entirely as user space daemons. Storage nodes
26utilize btrfs to store data objects, leveraging its advanced features
27(checksumming, metadata replication, etc.). File data is striped
28across storage nodes in large chunks to distribute workload and
29facilitate high throughputs. When storage nodes fail, data is
30re-replicated in a distributed fashion by the storage nodes themselves
31(with some minimal coordination from a cluster monitor), making the
32system extremely efficient and scalable.
33
34Metadata servers effectively form a large, consistent, distributed
35in-memory cache above the file namespace that is extremely scalable,
36dynamically redistributes metadata in response to workload changes,
37and can tolerate arbitrary (well, non-Byzantine) node failures. The
38metadata server takes a somewhat unconventional approach to metadata
39storage to significantly improve performance for common workloads. In
40particular, inodes with only a single link are embedded in
41directories, allowing entire directories of dentries and inodes to be
42loaded into its cache with a single I/O operation. The contents of
43extremely large directories can be fragmented and managed by
44independent metadata servers, allowing scalable concurrent access.
45
46The system offers automatic data rebalancing/migration when scaling
47from a small cluster of just a few nodes to many hundreds, without
48requiring an administrator carve the data set into static volumes or
49go through the tedious process of migrating data between servers.
50When the file system approaches full, new nodes can be easily added
51and things will "just work."
52
53Ceph includes flexible snapshot mechanism that allows a user to create
54a snapshot on any subdirectory (and its nested contents) in the
55system. Snapshot creation and deletion are as simple as 'mkdir
56.snap/foo' and 'rmdir .snap/foo'.
57
58Ceph also provides some recursive accounting on directories for nested
59files and bytes. That is, a 'getfattr -d foo' on any directory in the
60system will reveal the total number of nested regular files and
61subdirectories, and a summation of all nested file sizes. This makes
62the identification of large disk space consumers relatively quick, as
63no 'du' or similar recursive scan of the file system is required.
64
65
66Mount Syntax
67============
68
69The basic mount syntax is:
70
71 # mount -t ceph monip[:port][,monip2[:port]...]:/[subdir] mnt
72
73You only need to specify a single monitor, as the client will get the
74full list when it connects. (However, if the monitor you specify
75happens to be down, the mount won't succeed.) The port can be left
76off if the monitor is using the default. So if the monitor is at
771.2.3.4,
78
79 # mount -t ceph 1.2.3.4:/ /mnt/ceph
80
81is sufficient. If /sbin/mount.ceph is installed, a hostname can be
82used instead of an IP address.
83
84
85
86Mount Options
87=============
88
89 ip=A.B.C.D[:N]
90 Specify the IP and/or port the client should bind to locally.
91 There is normally not much reason to do this. If the IP is not
92 specified, the client's IP address is determined by looking at the
93 address it's connection to the monitor originates from.
94
95 wsize=X
96 Specify the maximum write size in bytes. By default there is no
97 maximum. Ceph will normally size writes based on the file stripe
98 size.
99
100 rsize=X
101 Specify the maximum readahead.
102
103 mount_timeout=X
104 Specify the timeout value for mount (in seconds), in the case
105 of a non-responsive Ceph file system. The default is 30
106 seconds.
107
108 rbytes
109 When stat() is called on a directory, set st_size to 'rbytes',
110 the summation of file sizes over all files nested beneath that
111 directory. This is the default.
112
113 norbytes
114 When stat() is called on a directory, set st_size to the
115 number of entries in that directory.
116
117 nocrc
118 Disable CRC32C calculation for data writes. If set, the storage node
119 must rely on TCP's error correction to detect data corruption
120 in the data payload.
121
122 noasyncreaddir
123 Disable client's use its local cache to satisfy readdir
124 requests. (This does not change correctness; the client uses
125 cached metadata only when a lease or capability ensures it is
126 valid.)
127
128
129More Information
130================
131
132For more information on Ceph, see the home page at
133 http://ceph.newdream.net/
134
135The Linux kernel client source tree is available at
136 git://ceph.newdream.net/git/ceph-client.git
137 git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client.git
138
139and the source for the full system is at
140 git://ceph.newdream.net/git/ceph.git
diff --git a/Documentation/filesystems/tmpfs.txt b/Documentation/filesystems/tmpfs.txt
index 3015da0c6b2a..fe09a2cb1858 100644
--- a/Documentation/filesystems/tmpfs.txt
+++ b/Documentation/filesystems/tmpfs.txt
@@ -82,11 +82,13 @@ tmpfs has a mount option to set the NUMA memory allocation policy for
82all files in that instance (if CONFIG_NUMA is enabled) - which can be 82all files in that instance (if CONFIG_NUMA is enabled) - which can be
83adjusted on the fly via 'mount -o remount ...' 83adjusted on the fly via 'mount -o remount ...'
84 84
85mpol=default prefers to allocate memory from the local node 85mpol=default use the process allocation policy
86 (see set_mempolicy(2))
86mpol=prefer:Node prefers to allocate memory from the given Node 87mpol=prefer:Node prefers to allocate memory from the given Node
87mpol=bind:NodeList allocates memory only from nodes in NodeList 88mpol=bind:NodeList allocates memory only from nodes in NodeList
88mpol=interleave prefers to allocate from each node in turn 89mpol=interleave prefers to allocate from each node in turn
89mpol=interleave:NodeList allocates from each node of NodeList in turn 90mpol=interleave:NodeList allocates from each node of NodeList in turn
91mpol=local prefers to allocate memory from the local node
90 92
91NodeList format is a comma-separated list of decimal numbers and ranges, 93NodeList format is a comma-separated list of decimal numbers and ranges,
92a range being two hyphen-separated decimal numbers, the smallest and 94a range being two hyphen-separated decimal numbers, the smallest and
@@ -134,3 +136,5 @@ Author:
134 Christoph Rohland <cr@sap.com>, 1.12.01 136 Christoph Rohland <cr@sap.com>, 1.12.01
135Updated: 137Updated:
136 Hugh Dickins, 4 June 2007 138 Hugh Dickins, 4 June 2007
139Updated:
140 KOSAKI Motohiro, 16 Mar 2010