[PATCH 1/2] tmpfs doc. question/update

[Randy Dunlap <randy.dunlap@oracle.com>]

Hi,

1.  Documentation/filesystems/tmpfs.txt says:

"""
2) glibc 2.2 and above expect tmpfs to be mounted at /dev/shm for
   POSIX shared memory (shm_open, shm_unlink). Adding the following
   line to /etc/fstab should take care of this:

	tmpfs	/dev/shm	tmpfs	defaults	0 0

   Remember to create the directory that you intend to mount tmpfs on
   if necessary.
"""

Is this still accurate?


2.  I have a few doc. updates:

---
From: Randy Dunlap <randy.dunlap@oracle.com>

Fix tmpfs.txt typos, language (ambiguities) etc.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
---
 Documentation/filesystems/tmpfs.txt |   39 ++++++++++++++++++------------------
 1 file changed, 20 insertions(+), 19 deletions(-)

--- linux-2.6.21-rc2-git4.orig/Documentation/filesystems/tmpfs.txt
+++ linux-2.6.21-rc2-git4/Documentation/filesystems/tmpfs.txt
@@ -10,16 +10,16 @@ shrinks to accommodate the files it cont
 unneeded pages out to swap space. It has maximum size limits which can
 be adjusted on the fly via 'mount -o remount ...'
 
-If you compare it to ramfs (which was the template to create tmpfs)
-you gain swapping and limit checking. Another similar thing is the RAM
-disk (/dev/ram*), which simulates a fixed size hard disk in physical
-RAM, where you have to create an ordinary filesystem on top. Ramdisks
-cannot swap and you do not have the possibility to resize them. 
+If you compare it to ramfs (which was the template to create tmpfs), you
+gain swapping and checking of limits (via mount options). Another similar
+thing is the RAM disk (/dev/ram*), which simulates a fixed size hard disk
+in physical RAM, where you have to create an ordinary filesystem on top.
+Ramdisks cannot swap and you do not have the possibility to resize them.
 
 Since tmpfs lives completely in the page cache and on swap, all tmpfs
-pages currently in memory will show up as cached. It will not show up
-as shared or something like that. Further on you can check the actual
-RAM+swap use of a tmpfs instance with df(1) and du(1).
+pages currently in memory will show up as cached. They will not show up
+as shared or something like that. You can check the actual RAM+swap use
+of a tmpfs instance with df(1) and du(1).
 
 
 tmpfs has the following uses:
@@ -29,10 +29,10 @@ tmpfs has the following uses:
    memory. 
 
    This mount does not depend on CONFIG_TMPFS. If CONFIG_TMPFS is not
-   set, the user visible part of tmpfs is not build. But the internal
+   set, the user visible part of tmpfs is not built, but the internal
    mechanisms are always present.
 
-2) glibc 2.2 and above expects tmpfs to be mounted at /dev/shm for
+2) glibc 2.2 and above expect tmpfs to be mounted at /dev/shm for
    POSIX shared memory (shm_open, shm_unlink). Adding the following
    line to /etc/fstab should take care of this:
 
@@ -44,7 +44,7 @@ tmpfs has the following uses:
    This mount is _not_ needed for SYSV shared memory. The internal
    mount is used for that. (In the 2.3 kernel versions it was
    necessary to mount the predecessor of tmpfs (shm fs) to use SYSV
-   shared memory)
+   shared memory.)
 
 3) Some people (including me) find it very convenient to mount it
    e.g. on /tmp and /var/tmp and have a big swap partition. And now
@@ -69,18 +69,18 @@ nr_inodes: The maximum number of inodes 
 These parameters accept a suffix k, m or g for kilo, mega and giga and
 can be changed on remount.  The size parameter also accepts a suffix %
 to limit this tmpfs instance to that percentage of your physical RAM:
-the default, when neither size nor nr_blocks is specified, is size=50%
+the default, when neither size nor nr_blocks is specified, is size=50%.
 
 If nr_blocks=0 (or size=0), blocks will not be limited in that instance;
 if nr_inodes=0, inodes will not be limited.  It is generally unwise to
 mount with such options, since it allows any user with write access to
 use up all the memory on the machine; but enhances the scalability of
-that instance in a system with many cpus making intensive use of it.
+that instance in a system with many CPUs making intensive use of it.
 
 
 tmpfs has a mount option to set the NUMA memory allocation policy for
-all files in that instance (if CONFIG_NUMA is enabled) - which can be
-adjusted on the fly via 'mount -o remount ...'
+all files in that instance (if CONFIG_NUMA is enabled).  This can be
+adjusted on the fly via 'mount -o remount ...'.  The mpol options are:
 
 mpol=default             prefers to allocate memory from the local node
 mpol=prefer:Node         prefers to allocate memory from the given Node
@@ -89,8 +89,9 @@ mpol=interleave          prefers to allo
 mpol=interleave:NodeList allocates from each node of NodeList in turn
 
 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
+a range being two hyphen-separated decimal numbers, representing the
+smallest and largest node numbers in the range.  For example:
+mpol=bind:0-3,5,7,9-15
 
 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
@@ -114,11 +115,11 @@ parameters with chmod(1), chown(1) and c
 
 
 So 'mount -t tmpfs -o size=10G,nr_inodes=10k,mode=700 tmpfs /mytmpfs'
-will give you tmpfs instance on /mytmpfs which can allocate 10GB
+will give you a tmpfs instance on /mytmpfs which can allocate 10GB
 RAM/SWAP in 10240 inodes and it is only accessible by root.
 
 
 Author:
-   Christoph Rohland <cr@sap.com>, 1.12.01
+   Christoph Rohland <cr@sap.com>, 01.DEC.2001
 Updated:
    Hugh Dickins <hugh@veritas.com>, 19 February 2006

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