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-rw-r--r--Documentation/filesystems/00-INDEX2
-rw-r--r--Documentation/filesystems/exofs.txt23
-rw-r--r--Documentation/filesystems/ext4.txt10
-rw-r--r--Documentation/filesystems/nilfs2.txt7
4 files changed, 27 insertions, 15 deletions
diff --git a/Documentation/filesystems/00-INDEX b/Documentation/filesystems/00-INDEX
index f15621ee559..7001782ab93 100644
--- a/Documentation/filesystems/00-INDEX
+++ b/Documentation/filesystems/00-INDEX
@@ -36,6 +36,8 @@ dnotify.txt
- info about directory notification in Linux.
ecryptfs.txt
- docs on eCryptfs: stacked cryptographic filesystem for Linux.
+exofs.txt
+ - info, usage, mount options, design about EXOFS.
ext2.txt
- info, mount options and specifications for the Ext2 filesystem.
ext3.txt
diff --git a/Documentation/filesystems/exofs.txt b/Documentation/filesystems/exofs.txt
index 0ced74c2f73..abd2a9b5b78 100644
--- a/Documentation/filesystems/exofs.txt
+++ b/Documentation/filesystems/exofs.txt
@@ -60,13 +60,13 @@ USAGE
mkfs.exofs --pid=65536 --format /dev/osd0
- The --format is optional if not specified no OSD_FORMAT will be
- preformed and a clean file system will be created in the specified pid,
+ The --format is optional. If not specified, no OSD_FORMAT will be
+ performed and a clean file system will be created in the specified pid,
in the available space of the target. (Use --format=size_in_meg to limit
the total LUN space available)
- If pid already exist it will be deleted and a new one will be created in it's
- place. Be careful.
+ If pid already exists, it will be deleted and a new one will be created in
+ its place. Be careful.
An exofs lives inside a single OSD partition. You can create multiple exofs
filesystems on the same device using multiple pids.
@@ -81,7 +81,7 @@ USAGE
7. For reference (See do-exofs example script):
do-exofs start - an example of how to perform the above steps.
- do-exofs stop - an example of how to unmount the file system.
+ do-exofs stop - an example of how to unmount the file system.
do-exofs format - an example of how to format and mkfs a new exofs.
8. Extra compilation flags (uncomment in fs/exofs/Kbuild):
@@ -104,8 +104,8 @@ Where:
exofs specific options: Options are separated by commas (,)
pid=<integer> - The partition number to mount/create as
container of the filesystem.
- This option is mandatory
- to=<integer> - Timeout in ticks for a single command
+ This option is mandatory.
+ to=<integer> - Timeout in ticks for a single command.
default is (60 * HZ) [for debugging only]
===============================================================================
@@ -116,7 +116,7 @@ DESIGN
with a special ID (defined in common.h).
Information included in the file system control block is used to fill the
in-memory superblock structure at mount time. This object is created before
- the file system is used by mkexofs.c It contains information such as:
+ the file system is used by mkexofs.c. It contains information such as:
- The file system's magic number
- The next inode number to be allocated
@@ -134,8 +134,8 @@ DESIGN
attributes. This applies to both regular files and other types (directories,
device files, symlinks, etc.).
-* Credentials are generated per object (inode and superblock) when they is
- created in memory (read off disk or created). The credential works for all
+* Credentials are generated per object (inode and superblock) when they are
+ created in memory (read from disk or created). The credential works for all
operations and is used as long as the object remains in memory.
* Async OSD operations are used whenever possible, but the target may execute
@@ -145,7 +145,8 @@ DESIGN
from executing in reverse order:
- The following are handled with the OBJ_CREATED and OBJ_2BCREATED
flags. OBJ_CREATED is set when we know the object exists on the OSD -
- in create's callback function, and when we successfully do a read_inode.
+ in create's callback function, and when we successfully do a
+ read_inode.
OBJ_2BCREATED is set in the beginning of the create function, so we
know that we should wait.
- create/delete: delete should wait until the object is created
diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt
index 6d94e0696f8..af6885c3c82 100644
--- a/Documentation/filesystems/ext4.txt
+++ b/Documentation/filesystems/ext4.txt
@@ -153,8 +153,8 @@ journal_dev=devnum When the external journal device's major/minor numbers
identified through its new major/minor numbers encoded
in devnum.
-noload Don't load the journal on mounting. Note that
- if the filesystem was not unmounted cleanly,
+norecovery Don't load the journal on mounting. Note that
+noload if the filesystem was not unmounted cleanly,
skipping the journal replay will lead to the
filesystem containing inconsistencies that can
lead to any number of problems.
@@ -353,6 +353,12 @@ noauto_da_alloc replacing existing files via patterns such as
system crashes before the delayed allocation
blocks are forced to disk.
+discard Controls whether ext4 should issue discard/TRIM
+nodiscard(*) commands to the underlying block device when
+ blocks are freed. This is useful for SSD devices
+ and sparse/thinly-provisioned LUNs, but it is off
+ by default until sufficient testing has been done.
+
Data Mode
=========
There are 3 different data modes:
diff --git a/Documentation/filesystems/nilfs2.txt b/Documentation/filesystems/nilfs2.txt
index 01539f41067..4949fcaa6b6 100644
--- a/Documentation/filesystems/nilfs2.txt
+++ b/Documentation/filesystems/nilfs2.txt
@@ -49,8 +49,7 @@ Mount options
NILFS2 supports the following mount options:
(*) == default
-barrier=on(*) This enables/disables barriers. barrier=off disables
- it, barrier=on enables it.
+nobarrier Disables barriers.
errors=continue(*) Keep going on a filesystem error.
errors=remount-ro Remount the filesystem read-only on an error.
errors=panic Panic and halt the machine if an error occurs.
@@ -71,6 +70,10 @@ order=strict Apply strict in-order semantics that preserves sequence
blocks. That means, it is guaranteed that no
overtaking of events occurs in the recovered file
system after a crash.
+norecovery Disable recovery of the filesystem on mount.
+ This disables every write access on the device for
+ read-only mounts or snapshots. This option will fail
+ for r/w mounts on an unclean volume.
NILFS2 usage
============