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authorJ. Bruce Fields <bfields@redhat.com>2012-10-10 02:35:22 +0400
committerJ. Bruce Fields <bfields@redhat.com>2012-10-10 02:35:22 +0400
commitf474af7051212b4efc8267583fad9c4ebf33ccff (patch)
tree1aa46ebc8065a341f247c2a2d9af2f624ad1d4f8 /Documentation/filesystems
parent0d22f68f02c10d5d10ec5712917e5828b001a822 (diff)
parente3dd9a52cb5552c46c2a4ca7ccdfb4dab5c72457 (diff)
downloadlinux-f474af7051212b4efc8267583fad9c4ebf33ccff.tar.xz
nfs: disintegrate UAPI for nfs
This is to complete part of the Userspace API (UAPI) disintegration for which the preparatory patches were pulled recently. After these patches, userspace headers will be segregated into: include/uapi/linux/.../foo.h for the userspace interface stuff, and: include/linux/.../foo.h for the strictly kernel internal stuff. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Diffstat (limited to 'Documentation/filesystems')
-rw-r--r--Documentation/filesystems/debugfs.txt4
-rw-r--r--Documentation/filesystems/ext4.txt10
-rw-r--r--Documentation/filesystems/jfs.txt19
-rw-r--r--Documentation/filesystems/nfs/nfsroot.txt10
-rw-r--r--Documentation/filesystems/proc.txt22
-rw-r--r--Documentation/filesystems/vfat.txt11
6 files changed, 51 insertions, 25 deletions
diff --git a/Documentation/filesystems/debugfs.txt b/Documentation/filesystems/debugfs.txt
index 7a34f827989c..3a863f692728 100644
--- a/Documentation/filesystems/debugfs.txt
+++ b/Documentation/filesystems/debugfs.txt
@@ -15,8 +15,8 @@ Debugfs is typically mounted with a command like:
mount -t debugfs none /sys/kernel/debug
(Or an equivalent /etc/fstab line).
-The debugfs root directory is accessible by anyone by default. To
-restrict access to the tree the "uid", "gid" and "mode" mount
+The debugfs root directory is accessible only to the root user by
+default. To change access to the tree the "uid", "gid" and "mode" mount
options can be used.
Note that the debugfs API is exported GPL-only to modules.
diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt
index 1b7f9acbcbbe..104322bf378c 100644
--- a/Documentation/filesystems/ext4.txt
+++ b/Documentation/filesystems/ext4.txt
@@ -375,6 +375,16 @@ dioread_nolock locking. If the dioread_nolock option is specified
Because of the restrictions this options comprises
it is off by default (e.g. dioread_lock).
+max_dir_size_kb=n This limits the size of directories so that any
+ attempt to expand them beyond the specified
+ limit in kilobytes will cause an ENOSPC error.
+ This is useful in memory constrained
+ environments, where a very large directory can
+ cause severe performance problems or even
+ provoke the Out Of Memory killer. (For example,
+ if there is only 512mb memory available, a 176mb
+ directory may seriously cramp the system's style.)
+
i_version Enable 64-bit inode version support. This option is
off by default.
diff --git a/Documentation/filesystems/jfs.txt b/Documentation/filesystems/jfs.txt
index 26ebde77e821..f7433355394a 100644
--- a/Documentation/filesystems/jfs.txt
+++ b/Documentation/filesystems/jfs.txt
@@ -3,6 +3,7 @@ IBM's Journaled File System (JFS) for Linux
JFS Homepage: http://jfs.sourceforge.net/
The following mount options are supported:
+(*) == default
iocharset=name Character set to use for converting from Unicode to
ASCII. The default is to do no conversion. Use
@@ -21,12 +22,12 @@ nointegrity Do not write to the journal. The primary use of this option
from backup media. The integrity of the volume is not
guaranteed if the system abnormally abends.
-integrity Default. Commit metadata changes to the journal. Use this
- option to remount a volume where the nointegrity option was
+integrity(*) Commit metadata changes to the journal. Use this option to
+ remount a volume where the nointegrity option was
previously specified in order to restore normal behavior.
errors=continue Keep going on a filesystem error.
-errors=remount-ro Default. Remount the filesystem read-only on an error.
+errors=remount-ro(*) Remount the filesystem read-only on an error.
errors=panic Panic and halt the machine if an error occurs.
uid=value Override on-disk uid with specified value
@@ -35,7 +36,17 @@ umask=value Override on-disk umask with specified octal value. For
directories, the execute bit will be set if the corresponding
read bit is set.
-Please send bugs, comments, cards and letters to shaggy@linux.vnet.ibm.com.
+discard=minlen This enables/disables the use of discard/TRIM commands.
+discard The discard/TRIM commands are sent to the underlying
+nodiscard(*) block device when blocks are freed. This is useful for SSD
+ devices and sparse/thinly-provisioned LUNs. The FITRIM ioctl
+ command is also available together with the nodiscard option.
+ The value of minlen specifies the minimum blockcount, when
+ a TRIM command to the block device is considered usefull.
+ When no value is given to the discard option, it defaults to
+ 64 blocks, which means 256KiB in JFS.
+ The minlen value of discard overrides the minlen value given
+ on an FITRIM ioctl().
The JFS mailing list can be subscribed to by using the link labeled
"Mail list Subscribe" at our web page http://jfs.sourceforge.net/
diff --git a/Documentation/filesystems/nfs/nfsroot.txt b/Documentation/filesystems/nfs/nfsroot.txt
index ffdd9d866ad7..2d66ed688125 100644
--- a/Documentation/filesystems/nfs/nfsroot.txt
+++ b/Documentation/filesystems/nfs/nfsroot.txt
@@ -78,7 +78,8 @@ nfsroot=[<server-ip>:]<root-dir>[,<nfs-options>]
flags = hard, nointr, noposix, cto, ac
-ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>
+ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>:
+ <dns0-ip>:<dns1-ip>
This parameter tells the kernel how to configure IP addresses of devices
and also how to set up the IP routing table. It was originally called
@@ -158,6 +159,13 @@ ip=<client-ip>:<server-ip>:<gw-ip>:<netmask>:<hostname>:<device>:<autoconf>
Default: any
+ <dns0-ip> IP address of first nameserver.
+ Value gets exported by /proc/net/pnp which is often linked
+ on embedded systems by /etc/resolv.conf.
+
+ <dns1-ip> IP address of secound nameserver.
+ Same as above.
+
nfsrootdebug
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index fb0a6aeb936c..a1793d670cd0 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -33,7 +33,7 @@ Table of Contents
2 Modifying System Parameters
3 Per-Process Parameters
- 3.1 /proc/<pid>/oom_adj & /proc/<pid>/oom_score_adj - Adjust the oom-killer
+ 3.1 /proc/<pid>/oom_score_adj - Adjust the oom-killer
score
3.2 /proc/<pid>/oom_score - Display current oom-killer score
3.3 /proc/<pid>/io - Display the IO accounting fields
@@ -1320,10 +1320,10 @@ of the kernel.
CHAPTER 3: PER-PROCESS PARAMETERS
------------------------------------------------------------------------------
-3.1 /proc/<pid>/oom_adj & /proc/<pid>/oom_score_adj- Adjust the oom-killer score
+3.1 /proc/<pid>/oom_score_adj- Adjust the oom-killer score
--------------------------------------------------------------------------------
-These file can be used to adjust the badness heuristic used to select which
+This file can be used to adjust the badness heuristic used to select which
process gets killed in out of memory conditions.
The badness heuristic assigns a value to each candidate task ranging from 0
@@ -1361,22 +1361,10 @@ same system, cpuset, mempolicy, or memory controller resources to use at least
equivalent to discounting 50% of the task's allowed memory from being considered
as scoring against the task.
-For backwards compatibility with previous kernels, /proc/<pid>/oom_adj may also
-be used to tune the badness score. Its acceptable values range from -16
-(OOM_ADJUST_MIN) to +15 (OOM_ADJUST_MAX) and a special value of -17
-(OOM_DISABLE) to disable oom killing entirely for that task. Its value is
-scaled linearly with /proc/<pid>/oom_score_adj.
-
-Writing to /proc/<pid>/oom_score_adj or /proc/<pid>/oom_adj will change the
-other with its scaled value.
-
The value of /proc/<pid>/oom_score_adj may be reduced no lower than the last
value set by a CAP_SYS_RESOURCE process. To reduce the value any lower
requires CAP_SYS_RESOURCE.
-NOTICE: /proc/<pid>/oom_adj is deprecated and will be removed, please see
-Documentation/feature-removal-schedule.txt.
-
Caveat: when a parent task is selected, the oom killer will sacrifice any first
generation children with separate address spaces instead, if possible. This
avoids servers and important system daemons from being killed and loses the
@@ -1387,9 +1375,7 @@ minimal amount of work.
-------------------------------------------------------------
This file can be used to check the current score used by the oom-killer is for
-any given <pid>. Use it together with /proc/<pid>/oom_adj to tune which
-process should be killed in an out-of-memory situation.
-
+any given <pid>.
3.3 /proc/<pid>/io - Display the IO accounting fields
-------------------------------------------------------
diff --git a/Documentation/filesystems/vfat.txt b/Documentation/filesystems/vfat.txt
index ead764b2728f..de1e6c4dccff 100644
--- a/Documentation/filesystems/vfat.txt
+++ b/Documentation/filesystems/vfat.txt
@@ -137,6 +137,17 @@ errors=panic|continue|remount-ro
without doing anything or remount the partition in
read-only mode (default behavior).
+discard -- If set, issues discard/TRIM commands to the block
+ device when blocks are freed. This is useful for SSD devices
+ and sparse/thinly-provisoned LUNs.
+
+nfs -- This option maintains an index (cache) of directory
+ inodes by i_logstart which is used by the nfs-related code to
+ improve look-ups.
+
+ Enable this only if you want to export the FAT filesystem
+ over NFS
+
<bool>: 0,1,yes,no,true,false
TODO