1
linux/include
David Howells 08734048b3 NFS: Define and create superblock-level objects
Define and create superblock-level cache index objects (as managed by
nfs_server structs).

Each superblock object is created in a server level index object and is itself
an index into which inode-level objects are inserted.

Ideally there would be one superblock-level object per server, and the former
would be folded into the latter; however, since the "nosharecache" option
exists this isn't possible.

The superblock object key is a sequence consisting of:

 (1) Certain superblock s_flags.

 (2) Various connection parameters that serve to distinguish superblocks for
     sget().

 (3) The volume FSID.

 (4) The security flavour.

 (5) The uniquifier length.

 (6) The uniquifier text.  This is normally an empty string, unless the fsc=xyz
     mount option was used to explicitly specify a uniquifier.

The key blob is of variable length, depending on the length of (6).

The superblock object is given no coherency data to carry in the auxiliary data
permitted by the cache.  It is assumed that the superblock is always coherent.

This patch also adds uniquification handling such that two otherwise identical
superblocks, at least one of which is marked "nosharecache", won't end up
trying to share the on-disk cache.  It will be possible to manually provide a
uniquifier through a mount option with a later patch to avoid the error
otherwise produced.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Steve Dickson <steved@redhat.com>
Acked-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Tested-by: Daire Byrne <Daire.Byrne@framestore.com>
2009-04-03 16:42:42 +01:00
..
acpi
asm-arm
asm-frv mm: use debug_kmap_atomic 2009-04-01 08:59:14 -07:00
asm-generic gpiolib: allow GPIOs to be named 2009-04-02 19:04:51 -07:00
asm-h8300
asm-m32r Allow rwlocks to re-enable interrupts 2009-04-02 19:05:11 -07:00
asm-mn10300 mm: use debug_kmap_atomic 2009-04-01 08:59:14 -07:00
crypto
drm drm: remove unused "can_grow" parameter from drm_crtc_helper_initial_config 2009-04-03 10:21:44 +10:00
keys
linux NFS: Define and create superblock-level objects 2009-04-03 16:42:42 +01:00
math-emu
media V4L/DVB (11313): v4l2-subdev: add enum_framesizes and enum_frameintervals. 2009-03-30 12:43:49 -03:00
mtd make MTD headers use strict integer types 2009-03-26 18:14:17 +01:00
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6 2009-04-02 21:05:30 -07:00
pcmcia
rdma Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6 2009-03-26 15:54:36 -07:00
rxrpc
scsi
sound V4L/DVB (10771): tea575x-tuner: convert it to V4L2 API 2009-03-30 12:43:02 -03:00
trace
video fbdev: update s1d13xxxfb to differ between revisions and production ids 2009-04-01 08:59:32 -07:00
xen
Kbuild