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-rw-r--r--Documentation/filesystems/9p.txt3
-rw-r--r--Documentation/filesystems/afs.txt26
-rw-r--r--Documentation/filesystems/ext4.txt24
-rw-r--r--Documentation/filesystems/gfs2-uevents.txt100
-rw-r--r--Documentation/filesystems/nfsroot.txt2
-rw-r--r--Documentation/filesystems/proc.txt37
-rw-r--r--Documentation/filesystems/seq_file.txt2
7 files changed, 153 insertions, 41 deletions
diff --git a/Documentation/filesystems/9p.txt b/Documentation/filesystems/9p.txt
index bf8080640eba..6208f55c44c3 100644
--- a/Documentation/filesystems/9p.txt
+++ b/Documentation/filesystems/9p.txt
@@ -123,6 +123,9 @@ available from the same CVS repository.
123There are user and developer mailing lists available through the v9fs project 123There are user and developer mailing lists available through the v9fs project
124on sourceforge (http://sourceforge.net/projects/v9fs). 124on sourceforge (http://sourceforge.net/projects/v9fs).
125 125
126A stand-alone version of the module (which should build for any 2.6 kernel)
127is available via (http://github.com/ericvh/9p-sac/tree/master)
128
126News and other information is maintained on SWiK (http://swik.net/v9fs). 129News and other information is maintained on SWiK (http://swik.net/v9fs).
127 130
128Bug reports may be issued through the kernel.org bugzilla 131Bug reports may be issued through the kernel.org bugzilla
diff --git a/Documentation/filesystems/afs.txt b/Documentation/filesystems/afs.txt
index 12ad6c7f4e50..ffef91c4e0d6 100644
--- a/Documentation/filesystems/afs.txt
+++ b/Documentation/filesystems/afs.txt
@@ -23,15 +23,13 @@ it does support include:
23 23
24 (*) Security (currently only AFS kaserver and KerberosIV tickets). 24 (*) Security (currently only AFS kaserver and KerberosIV tickets).
25 25
26 (*) File reading. 26 (*) File reading and writing.
27 27
28 (*) Automounting. 28 (*) Automounting.
29 29
30It does not yet support the following AFS features: 30 (*) Local caching (via fscache).
31
32 (*) Write support.
33 31
34 (*) Local caching. 32It does not yet support the following AFS features:
35 33
36 (*) pioctl() system call. 34 (*) pioctl() system call.
37 35
@@ -56,7 +54,7 @@ They permit the debugging messages to be turned on dynamically by manipulating
56the masks in the following files: 54the masks in the following files:
57 55
58 /sys/module/af_rxrpc/parameters/debug 56 /sys/module/af_rxrpc/parameters/debug
59 /sys/module/afs/parameters/debug 57 /sys/module/kafs/parameters/debug
60 58
61 59
62===== 60=====
@@ -66,9 +64,9 @@ USAGE
66When inserting the driver modules the root cell must be specified along with a 64When inserting the driver modules the root cell must be specified along with a
67list of volume location server IP addresses: 65list of volume location server IP addresses:
68 66
69 insmod af_rxrpc.o 67 modprobe af_rxrpc
70 insmod rxkad.o 68 modprobe rxkad
71 insmod kafs.o rootcell=cambridge.redhat.com:172.16.18.73:172.16.18.91 69 modprobe kafs rootcell=cambridge.redhat.com:172.16.18.73:172.16.18.91
72 70
73The first module is the AF_RXRPC network protocol driver. This provides the 71The first module is the AF_RXRPC network protocol driver. This provides the
74RxRPC remote operation protocol and may also be accessed from userspace. See: 72RxRPC remote operation protocol and may also be accessed from userspace. See:
@@ -81,7 +79,7 @@ is the actual filesystem driver for the AFS filesystem.
81Once the module has been loaded, more modules can be added by the following 79Once the module has been loaded, more modules can be added by the following
82procedure: 80procedure:
83 81
84 echo add grand.central.org 18.7.14.88:128.2.191.224 >/proc/fs/afs/cells 82 echo add grand.central.org 18.9.48.14:128.2.203.61:130.237.48.87 >/proc/fs/afs/cells
85 83
86Where the parameters to the "add" command are the name of a cell and a list of 84Where the parameters to the "add" command are the name of a cell and a list of
87volume location servers within that cell, with the latter separated by colons. 85volume location servers within that cell, with the latter separated by colons.
@@ -101,7 +99,7 @@ The name of the volume can be suffixes with ".backup" or ".readonly" to
101specify connection to only volumes of those types. 99specify connection to only volumes of those types.
102 100
103The name of the cell is optional, and if not given during a mount, then the 101The name of the cell is optional, and if not given during a mount, then the
104named volume will be looked up in the cell specified during insmod. 102named volume will be looked up in the cell specified during modprobe.
105 103
106Additional cells can be added through /proc (see later section). 104Additional cells can be added through /proc (see later section).
107 105
@@ -163,14 +161,14 @@ THE CELL DATABASE
163 161
164The filesystem maintains an internal database of all the cells it knows and the 162The filesystem maintains an internal database of all the cells it knows and the
165IP addresses of the volume location servers for those cells. The cell to which 163IP addresses of the volume location servers for those cells. The cell to which
166the system belongs is added to the database when insmod is performed by the 164the system belongs is added to the database when modprobe is performed by the
167"rootcell=" argument or, if compiled in, using a "kafs.rootcell=" argument on 165"rootcell=" argument or, if compiled in, using a "kafs.rootcell=" argument on
168the kernel command line. 166the kernel command line.
169 167
170Further cells can be added by commands similar to the following: 168Further cells can be added by commands similar to the following:
171 169
172 echo add CELLNAME VLADDR[:VLADDR][:VLADDR]... >/proc/fs/afs/cells 170 echo add CELLNAME VLADDR[:VLADDR][:VLADDR]... >/proc/fs/afs/cells
173 echo add grand.central.org 18.7.14.88:128.2.191.224 >/proc/fs/afs/cells 171 echo add grand.central.org 18.9.48.14:128.2.203.61:130.237.48.87 >/proc/fs/afs/cells
174 172
175No other cell database operations are available at this time. 173No other cell database operations are available at this time.
176 174
@@ -233,7 +231,7 @@ insmod /tmp/kafs.o rootcell=cambridge.redhat.com:172.16.18.91
233mount -t afs \%root.afs. /afs 231mount -t afs \%root.afs. /afs
234mount -t afs \%cambridge.redhat.com:root.cell. /afs/cambridge.redhat.com/ 232mount -t afs \%cambridge.redhat.com:root.cell. /afs/cambridge.redhat.com/
235 233
236echo add grand.central.org 18.7.14.88:128.2.191.224 > /proc/fs/afs/cells 234echo add grand.central.org 18.9.48.14:128.2.203.61:130.237.48.87 > /proc/fs/afs/cells
237mount -t afs "#grand.central.org:root.cell." /afs/grand.central.org/ 235mount -t afs "#grand.central.org:root.cell." /afs/grand.central.org/
238mount -t afs "#grand.central.org:root.archive." /afs/grand.central.org/archive 236mount -t afs "#grand.central.org:root.archive." /afs/grand.central.org/archive
239mount -t afs "#grand.central.org:root.contrib." /afs/grand.central.org/contrib 237mount -t afs "#grand.central.org:root.contrib." /afs/grand.central.org/contrib
diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt
index 7be02ac5fa36..18b5ec8cea45 100644
--- a/Documentation/filesystems/ext4.txt
+++ b/Documentation/filesystems/ext4.txt
@@ -134,15 +134,9 @@ ro Mount filesystem read only. Note that ext4 will
134 mount options "ro,noload" can be used to prevent 134 mount options "ro,noload" can be used to prevent
135 writes to the filesystem. 135 writes to the filesystem.
136 136
137journal_checksum Enable checksumming of the journal transactions.
138 This will allow the recovery code in e2fsck and the
139 kernel to detect corruption in the kernel. It is a
140 compatible change and will be ignored by older kernels.
141
142journal_async_commit Commit block can be written to disk without waiting 137journal_async_commit Commit block can be written to disk without waiting
143 for descriptor blocks. If enabled older kernels cannot 138 for descriptor blocks. If enabled older kernels cannot
144 mount the device. This will enable 'journal_checksum' 139 mount the device.
145 internally.
146 140
147journal=update Update the ext4 file system's journal to the current 141journal=update Update the ext4 file system's journal to the current
148 format. 142 format.
@@ -263,10 +257,18 @@ resuid=n The user ID which may use the reserved blocks.
263 257
264sb=n Use alternate superblock at this location. 258sb=n Use alternate superblock at this location.
265 259
266quota 260quota These options are ignored by the filesystem. They
267noquota 261noquota are used only by quota tools to recognize volumes
268grpquota 262grpquota where quota should be turned on. See documentation
269usrquota 263usrquota in the quota-tools package for more details
264 (http://sourceforge.net/projects/linuxquota).
265
266jqfmt=<quota type> These options tell filesystem details about quota
267usrjquota=<file> so that quota information can be properly updated
268grpjquota=<file> during journal replay. They replace the above
269 quota options. See documentation in the quota-tools
270 package for more details
271 (http://sourceforge.net/projects/linuxquota).
270 272
271bh (*) ext4 associates buffer heads to data pages to 273bh (*) ext4 associates buffer heads to data pages to
272nobh (a) cache disk block mapping information 274nobh (a) cache disk block mapping information
diff --git a/Documentation/filesystems/gfs2-uevents.txt b/Documentation/filesystems/gfs2-uevents.txt
new file mode 100644
index 000000000000..fd966dc9979a
--- /dev/null
+++ b/Documentation/filesystems/gfs2-uevents.txt
@@ -0,0 +1,100 @@
1 uevents and GFS2
2 ==================
3
4During the lifetime of a GFS2 mount, a number of uevents are generated.
5This document explains what the events are and what they are used
6for (by gfs_controld in gfs2-utils).
7
8A list of GFS2 uevents
9-----------------------
10
111. ADD
12
13The ADD event occurs at mount time. It will always be the first
14uevent generated by the newly created filesystem. If the mount
15is successful, an ONLINE uevent will follow. If it is not successful
16then a REMOVE uevent will follow.
17
18The ADD uevent has two environment variables: SPECTATOR=[0|1]
19and RDONLY=[0|1] that specify the spectator status (a read-only mount
20with no journal assigned), and read-only (with journal assigned) status
21of the filesystem respectively.
22
232. ONLINE
24
25The ONLINE uevent is generated after a successful mount or remount. It
26has the same environment variables as the ADD uevent. The ONLINE
27uevent, along with the two environment variables for spectator and
28RDONLY are a relatively recent addition (2.6.32-rc+) and will not
29be generated by older kernels.
30
313. CHANGE
32
33The CHANGE uevent is used in two places. One is when reporting the
34successful mount of the filesystem by the first node (FIRSTMOUNT=Done).
35This is used as a signal by gfs_controld that it is then ok for other
36nodes in the cluster to mount the filesystem.
37
38The other CHANGE uevent is used to inform of the completion
39of journal recovery for one of the filesystems journals. It has
40two environment variables, JID= which specifies the journal id which
41has just been recovered, and RECOVERY=[Done|Failed] to indicate the
42success (or otherwise) of the operation. These uevents are generated
43for every journal recovered, whether it is during the initial mount
44process or as the result of gfs_controld requesting a specific journal
45recovery via the /sys/fs/gfs2/<fsname>/lock_module/recovery file.
46
47Because the CHANGE uevent was used (in early versions of gfs_controld)
48without checking the environment variables to discover the state, we
49cannot add any more functions to it without running the risk of
50someone using an older version of the user tools and breaking their
51cluster. For this reason the ONLINE uevent was used when adding a new
52uevent for a successful mount or remount.
53
544. OFFLINE
55
56The OFFLINE uevent is only generated due to filesystem errors and is used
57as part of the "withdraw" mechanism. Currently this doesn't give any
58information about what the error is, which is something that needs to
59be fixed.
60
615. REMOVE
62
63The REMOVE uevent is generated at the end of an unsuccessful mount
64or at the end of a umount of the filesystem. All REMOVE uevents will
65have been preceeded by at least an ADD uevent for the same fileystem,
66and unlike the other uevents is generated automatically by the kernel's
67kobject subsystem.
68
69
70Information common to all GFS2 uevents (uevent environment variables)
71----------------------------------------------------------------------
72
731. LOCKTABLE=
74
75The LOCKTABLE is a string, as supplied on the mount command
76line (locktable=) or via fstab. It is used as a filesystem label
77as well as providing the information for a lock_dlm mount to be
78able to join the cluster.
79
802. LOCKPROTO=
81
82The LOCKPROTO is a string, and its value depends on what is set
83on the mount command line, or via fstab. It will be either
84lock_nolock or lock_dlm. In the future other lock managers
85may be supported.
86
873. JOURNALID=
88
89If a journal is in use by the filesystem (journals are not
90assigned for spectator mounts) then this will give the
91numeric journal id in all GFS2 uevents.
92
934. UUID=
94
95With recent versions of gfs2-utils, mkfs.gfs2 writes a UUID
96into the filesystem superblock. If it exists, this will
97be included in every uevent relating to the filesystem.
98
99
100
diff --git a/Documentation/filesystems/nfsroot.txt b/Documentation/filesystems/nfsroot.txt
index 68baddf3c3e0..3ba0b945aaf8 100644
--- a/Documentation/filesystems/nfsroot.txt
+++ b/Documentation/filesystems/nfsroot.txt
@@ -105,7 +105,7 @@ ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>
105 the client address and this parameter is NOT empty only 105 the client address and this parameter is NOT empty only
106 replies from the specified server are accepted. 106 replies from the specified server are accepted.
107 107
108 Only required for for NFS root. That is autoconfiguration 108 Only required for NFS root. That is autoconfiguration
109 will not be triggered if it is missing and NFS root is not 109 will not be triggered if it is missing and NFS root is not
110 in operation. 110 in operation.
111 111
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index fad18f9456e4..75988ba26a51 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -375,6 +375,19 @@ of memory currently marked as referenced or accessed.
375This file is only present if the CONFIG_MMU kernel configuration option is 375This file is only present if the CONFIG_MMU kernel configuration option is
376enabled. 376enabled.
377 377
378The /proc/PID/clear_refs is used to reset the PG_Referenced and ACCESSED/YOUNG
379bits on both physical and virtual pages associated with a process.
380To clear the bits for all the pages associated with the process
381 > echo 1 > /proc/PID/clear_refs
382
383To clear the bits for the anonymous pages associated with the process
384 > echo 2 > /proc/PID/clear_refs
385
386To clear the bits for the file mapped pages associated with the process
387 > echo 3 > /proc/PID/clear_refs
388Any other value written to /proc/PID/clear_refs will have no effect.
389
390
3781.2 Kernel data 3911.2 Kernel data
379--------------- 392---------------
380 393
@@ -1032,9 +1045,9 @@ Various pieces of information about kernel activity are available in the
1032since the system first booted. For a quick look, simply cat the file: 1045since the system first booted. For a quick look, simply cat the file:
1033 1046
1034 > cat /proc/stat 1047 > cat /proc/stat
1035 cpu 2255 34 2290 22625563 6290 127 456 0 1048 cpu 2255 34 2290 22625563 6290 127 456 0 0
1036 cpu0 1132 34 1441 11311718 3675 127 438 0 1049 cpu0 1132 34 1441 11311718 3675 127 438 0 0
1037 cpu1 1123 0 849 11313845 2614 0 18 0 1050 cpu1 1123 0 849 11313845 2614 0 18 0 0
1038 intr 114930548 113199788 3 0 5 263 0 4 [... lots more numbers ...] 1051 intr 114930548 113199788 3 0 5 263 0 4 [... lots more numbers ...]
1039 ctxt 1990473 1052 ctxt 1990473
1040 btime 1062191376 1053 btime 1062191376
@@ -1056,6 +1069,7 @@ second). The meanings of the columns are as follows, from left to right:
1056- irq: servicing interrupts 1069- irq: servicing interrupts
1057- softirq: servicing softirqs 1070- softirq: servicing softirqs
1058- steal: involuntary wait 1071- steal: involuntary wait
1072- guest: running a guest
1059 1073
1060The "intr" line gives counts of interrupts serviced since boot time, for each 1074The "intr" line gives counts of interrupts serviced since boot time, for each
1061of the possible system interrupts. The first column is the total of all 1075of the possible system interrupts. The first column is the total of all
@@ -1167,13 +1181,11 @@ CHAPTER 3: PER-PROCESS PARAMETERS
11673.1 /proc/<pid>/oom_adj - Adjust the oom-killer score 11813.1 /proc/<pid>/oom_adj - Adjust the oom-killer score
1168------------------------------------------------------ 1182------------------------------------------------------
1169 1183
1170This file can be used to adjust the score used to select which processes should 1184This file can be used to adjust the score used to select which processes
1171be killed in an out-of-memory situation. The oom_adj value is a characteristic 1185should be killed in an out-of-memory situation. Giving it a high score will
1172of the task's mm, so all threads that share an mm with pid will have the same 1186increase the likelihood of this process being killed by the oom-killer. Valid
1173oom_adj value. A high value will increase the likelihood of this process being 1187values are in the range -16 to +15, plus the special value -17, which disables
1174killed by the oom-killer. Valid values are in the range -16 to +15 as 1188oom-killing altogether for this process.
1175explained below and a special value of -17, which disables oom-killing
1176altogether for threads sharing pid's mm.
1177 1189
1178The process to be killed in an out-of-memory situation is selected among all others 1190The process to be killed in an out-of-memory situation is selected among all others
1179based on its badness score. This value equals the original memory size of the process 1191based on its badness score. This value equals the original memory size of the process
@@ -1187,16 +1199,13 @@ the parent's score if they do not share the same memory. Thus forking servers
1187are the prime candidates to be killed. Having only one 'hungry' child will make 1199are the prime candidates to be killed. Having only one 'hungry' child will make
1188parent less preferable than the child. 1200parent less preferable than the child.
1189 1201
1190/proc/<pid>/oom_adj cannot be changed for kthreads since they are immune from
1191oom-killing already.
1192
1193/proc/<pid>/oom_score shows process' current badness score. 1202/proc/<pid>/oom_score shows process' current badness score.
1194 1203
1195The following heuristics are then applied: 1204The following heuristics are then applied:
1196 * if the task was reniced, its score doubles 1205 * if the task was reniced, its score doubles
1197 * superuser or direct hardware access tasks (CAP_SYS_ADMIN, CAP_SYS_RESOURCE 1206 * superuser or direct hardware access tasks (CAP_SYS_ADMIN, CAP_SYS_RESOURCE
1198 or CAP_SYS_RAWIO) have their score divided by 4 1207 or CAP_SYS_RAWIO) have their score divided by 4
1199 * if oom condition happened in one cpuset and checked task does not belong 1208 * if oom condition happened in one cpuset and checked process does not belong
1200 to it, its score is divided by 8 1209 to it, its score is divided by 8
1201 * the resulting score is multiplied by two to the power of oom_adj, i.e. 1210 * the resulting score is multiplied by two to the power of oom_adj, i.e.
1202 points <<= oom_adj when it is positive and 1211 points <<= oom_adj when it is positive and
diff --git a/Documentation/filesystems/seq_file.txt b/Documentation/filesystems/seq_file.txt
index b843743aa0b5..0d15ebccf5b0 100644
--- a/Documentation/filesystems/seq_file.txt
+++ b/Documentation/filesystems/seq_file.txt
@@ -46,7 +46,7 @@ better to do. The file is seekable, in that one can do something like the
46following: 46following:
47 47
48 dd if=/proc/sequence of=out1 count=1 48 dd if=/proc/sequence of=out1 count=1
49 dd if=/proc/sequence skip=1 out=out2 count=1 49 dd if=/proc/sequence skip=1 of=out2 count=1
50 50
51Then concatenate the output files out1 and out2 and get the right 51Then concatenate the output files out1 and out2 and get the right
52result. Yes, it is a thoroughly useless module, but the point is to show 52result. Yes, it is a thoroughly useless module, but the point is to show