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5 commits

Author SHA1 Message Date
Luis Chamberlain
2c6efe9cf2 shmem: add support to ignore swap
In doing experimentations with shmem having the option to avoid swap
becomes a useful mechanism.  One of the *raves* about brd over shmem is
you can avoid swap, but that's not really a good reason to use brd if we
can instead use shmem.  Using brd has its own good reasons to exist, but
just because "tmpfs" doesn't let you do that is not a great reason to
avoid it if we can easily add support for it.

I don't add support for reconfiguring incompatible options, but if we
really wanted to we can add support for that.

To avoid swap we use mapping_set_unevictable() upon inode creation, and
put a WARN_ON_ONCE() stop-gap on writepages() for reclaim.

Link: https://lkml.kernel.org/r/20230309230545.2930737-7-mcgrof@kernel.org
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Christian Brauner <brauner@kernel.org>
Tested-by: Xin Hao <xhao@linux.alibaba.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Cc: Adam Manzanares <a.manzanares@samsung.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-03-28 16:20:15 -07:00
Luis Chamberlain
d0f5a85442 shmem: update documentation
Update the docs to reflect a bit better why some folks prefer tmpfs over
ramfs and clarify a bit more about the difference between brd ramdisks.

While at it, add THP docs for tmpfs, both the mount options and the sysfs
file.

Link: https://lkml.kernel.org/r/20230309230545.2930737-6-mcgrof@kernel.org
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Tested-by: Xin Hao <xhao@linux.alibaba.com>
Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
Cc: Adam Manzanares <a.manzanares@samsung.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-03-28 16:20:15 -07:00
Randy Dunlap
f38d58b734 tmpfs: fix Documentation nits
Fix a typo, punctuation, use uppercase for CPUs, and limit
tmpfs to keeping only its files in virtual memory (phrasing).

Link: https://lkml.kernel.org/r/20201202010934.18566-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Chris Down <chris@chrisdown.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-12-15 12:13:39 -08:00
Chris Down
ea3271f719 tmpfs: support 64-bit inums per-sb
The default is still set to inode32 for backwards compatibility, but
system administrators can opt in to the new 64-bit inode numbers by
either:

1. Passing inode64 on the command line when mounting, or
2. Configuring the kernel with CONFIG_TMPFS_INODE64=y

The inode64 and inode32 names are used based on existing precedent from
XFS.

[hughd@google.com: Kconfig fixes]
  Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008011928010.13320@eggly.anvils

Signed-off-by: Chris Down <chris@chrisdown.name>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/8b23758d0c66b5e2263e08baf9c4b6a7565cbd8f.1594661218.git.chris@chrisdown.name
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:24 -07:00
Mauro Carvalho Chehab
7e7cd458b8 docs: filesystems: convert tmpfs.txt to ReST
- Add a SPDX header;
- Add a document title;
- Some whitespace fixes and new line breaks;
- Mark literal blocks as such;
- Add table markups;
- Use :field: markup;
- Add it to filesystems/index.rst.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/30397a47a78ca59760fbc0fc5f50c5f1002d487a.1581955849.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-03-02 14:04:41 -07:00
Renamed from Documentation/filesystems/tmpfs.txt (Browse further)