linux.git/fs/ramfs/inode.c, branch v4.2

fs: remove mapping->backing_dev_info

2015-01-20T21:03:05+00:00

Now that we never use the backing_dev_info pointer in struct address_space
we can simply remove it and save 4 to 8 bytes in every inode.

Signed-off-by: Christoph Hellwig 
Acked-by: Ryusuke Konishi 
Reviewed-by: Tejun Heo 
Reviewed-by: Jan Kara 
Signed-off-by: Jens Axboe

fs: introduce f_op->mmap_capabilities for nommu mmap support

2015-01-20T21:02:58+00:00

Since "BDI: Provide backing device capability information [try #3]" the
backing_dev_info structure also provides flags for the kind of mmap
operation available in a nommu environment, which is entirely unrelated
to it's original purpose.

Introduce a new nommu-only file operation to provide this information to
the nommu mmap code instead.  Splitting this from the backing_dev_info
structure allows to remove lots of backing_dev_info instance that aren't
otherwise needed, and entirely gets rid of the concept of providing a
backing_dev_info for a character device.  It also removes the need for
the mtd_inodefs filesystem.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Tejun Heo 
Acked-by: Brian Norris 
Signed-off-by: Jens Axboe

fs/ramfs: move ramfs_aops to inode.c

2014-01-24T00:36:58+00:00

ramfs_aops is identical in file-mmu.c and file-nommu.c.  Thus move it to
fs/ramfs/inode.c and make it static.

Signed-off-by: Axel Lin 
Cc: Al Viro 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

fs/ramfs: don't use module_init for non-modular core code

2014-01-22T00:19:42+00:00

The ramfs is always built in.  It will never be modular, so using
module_init as an alias for __initcall is rather misleading.

Fix this up now, so that we can relocate module_init from init.h into
module.h in the future.  If we don't do this, we'd have to add module.h
to obviously non-modular code, and that would be a worse thing.

Note that direct use of __initcall is discouraged, vs.  one of the
priority categorized subgroups.  As __initcall gets mapped onto
device_initcall, our use of fs_initcall (which makes sense for fs code)
will thus change this registration from level 6-device to level 5-fs
(i.e. slightly earlier).  However no observable impact of that small
difference has been observed during testing, or is expected.

Also note that this change uncovers a missing semicolon bug in the
registration of the initcall.

Signed-off-by: Paul Gortmaker 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

initmpfs: move rootfs code from fs/ramfs/ to init/

2013-09-11T22:59:37+00:00

When the rootfs code was a wrapper around ramfs, having them in the same
file made sense.  Now that it can wrap another filesystem type, move it in
with the init code instead.

This also allows a subsequent patch to access rootfstype= command line
arg.

Signed-off-by: Rob Landley 
Cc: Jeff Layton 
Cc: Jens Axboe 
Cc: Stephen Warren 
Cc: Rusty Russell 
Cc: Jim Cromie 
Cc: Sam Ravnborg 
Cc: Greg Kroah-Hartman 
Cc: "Eric W. Biederman" 
Cc: Alexander Viro 
Cc: "H. Peter Anvin" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

initmpfs: move bdi setup from init_rootfs to init_ramfs

2013-09-11T22:59:37+00:00

Even though ramfs hasn't got a backing device, commit e0bf68ddec4f ("mm:
bdi init hooks") added one anyway, and put the initialization in
init_rootfs() since that's the first user, leaving it out of init_ramfs()
to avoid duplication.

But initmpfs uses init_tmpfs() instead, so move the init into the
filesystem's init function, add a "once" guard to prevent duplicate
initialization, and call the filesystem init from rootfs init.

This goes part of the way to allowing ramfs to be built as a module.

[akpm@linux-foundation.org; using bit 1 was odd]
Signed-off-by: Rob Landley 
Cc: Jeff Layton 
Cc: Jens Axboe 
Cc: Stephen Warren 
Cc: Rusty Russell 
Cc: Jim Cromie 
Cc: Sam Ravnborg 
Cc: Greg Kroah-Hartman 
Cc: "Eric W. Biederman" 
Cc: Alexander Viro 
Cc: "H. Peter Anvin" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

initmpfs: replace MS_NOUSER in initramfs

2013-09-11T22:59:36+00:00

Mounting MS_NOUSER prevents --bind mounts from rootfs.  Prevent new rootfs
mounts with a different mechanism that doesn't affect bind mounts.

Signed-off-by: Rob Landley 
Cc: Jeff Layton 
Cc: Jens Axboe 
Cc: Stephen Warren 
Cc: Rusty Russell 
Cc: Jim Cromie 
Cc: Sam Ravnborg 
Cc: Greg Kroah-Hartman 
Cc: "Eric W. Biederman" 
Cc: Alexander Viro 
Cc: "H. Peter Anvin" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

userns: Allow the userns root to mount ramfs.

2013-01-27T06:22:38+00:00

There is no backing store to ramfs and file creation
rules are the same as for any other filesystem so
it is semantically safe to allow unprivileged users
to mount it.

The memory control group successfully limits how much
memory ramfs can consume on any system that cares about
a user namespace root using ramfs to exhaust memory
the memory control group can be deployed.

Signed-off-by: "Eric W. Biederman"

don't pass nameidata to ->create()

2012-07-14T12:34:47+00:00

boolean "does it have to be exclusive?" flag is passed instead;
Local filesystem should just ignore it - the object is guaranteed
not to be there yet.

Signed-off-by: Al Viro

tidy up after d_make_root() conversion

2012-03-21T01:29:37+00:00

Signed-off-by: Al Viro