The noswap mount option is surely not one of the three options for sizing:
move its description down.
The huge= mount option does not accept numeric values: those are just in
an internal enum. Delete those numbers, and follow the manpage text more
closely (but there's not yet any fadvise() or fcntl() which applies here).
/sys/kernel/mm/transparent_hugepage/shmem_enabled is hard to describe, and
barely relevant to mounting a tmpfs: just refer to transhuge.rst (while
still using the words deny and force, to help as informal reminders).
[rdunlap@infradead.org: fixup Docs table for huge mount options]
Link: https://lkml.kernel.org/r/20230725052333.26857-1-rdunlap@infradead.org
Link: https://lkml.kernel.org/r/986cb0bf-9780-354-9bb-4bf57aadbab@google.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Fixes: d0f5a85442 ("shmem: update documentation")
Fixes: 2c6efe9cf2 ("shmem: add support to ignore swap")
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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>
