linux/include
David Howells 3e1aeb00e6 vfs: Implement a filesystem superblock creation/configuration context
[AV - unfuck kern_mount_data(); we want non-NULL ->mnt_ns on long-living
mounts]
[AV - reordering fs/namespace.c is badly overdue, but let's keep it
separate from that series]
[AV - drop simple_pin_fs() change]
[AV - clean vfs_kern_mount() failure exits up]

Implement a filesystem context concept to be used during superblock
creation for mount and superblock reconfiguration for remount.

The mounting procedure then becomes:

 (1) Allocate new fs_context context.

 (2) Configure the context.

 (3) Create superblock.

 (4) Query the superblock.

 (5) Create a mount for the superblock.

 (6) Destroy the context.

Rather than calling fs_type->mount(), an fs_context struct is created and
fs_type->init_fs_context() is called to set it up.  Pointers exist for the
filesystem and LSM to hang their private data off.

A set of operations has to be set by ->init_fs_context() to provide
freeing, duplication, option parsing, binary data parsing, validation,
mounting and superblock filling.

Legacy filesystems are supported by the provision of a set of legacy
fs_context operations that build up a list of mount options and then invoke
fs_type->mount() from within the fs_context ->get_tree() operation.  This
allows all filesystems to be accessed using fs_context.

It should be noted that, whilst this patch adds a lot of lines of code,
there is quite a bit of duplication with existing code that can be
eliminated should all filesystems be converted over.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2019-02-28 03:29:26 -05:00
..
acpi Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-12-26 17:03:51 -08:00
asm-generic Merge branch 'akpm' (patches from Andrew) 2019-01-05 09:16:18 -08:00
clocksource
crypto crypto: skcipher - remove remnants of internal IV generators 2018-12-23 11:52:45 +08:00
drm Merge tag 'drm-intel-fixes-2019-01-11' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes 2019-01-11 10:26:21 +01:00
dt-bindings Merge branch 'next/drivers' into next/late 2019-01-04 14:31:38 -08:00
keys
kvm KVM: arm/arm64: Remove arch timer workqueue 2018-12-19 17:47:07 +00:00
linux vfs: Implement a filesystem superblock creation/configuration context 2019-02-28 03:29:26 -05:00
math-emu
media media fixes for v4.20-rc8 2018-12-25 13:11:30 -08:00
memory
misc
net Remove 'type' argument from access_ok() function 2019-01-03 18:57:57 -08:00
pcmcia
ras
rdma IB/core: uverbs copy to struct or zero helper 2018-12-20 15:18:18 -07:00
scsi 4.21 merge window pull request 2018-12-28 14:57:10 -08:00
soc ARM: SoC driver updates 2018-12-31 17:32:35 -08:00
sound ALSA: HD-Audio: SKL+: force HDaudio legacy or SKL+ driver selection 2018-12-19 18:07:23 +01:00
target
trace NFS client updates for Linux 4.21 2019-01-02 16:35:23 -08:00
uapi Fix a handful of audit-related issue 2019-01-07 08:45:47 -08:00
video
xen xen: Introduce shared buffer helpers for page directory... 2018-12-18 12:15:55 -05:00