[GIT PULL] afs: Filesystem driver overhaul

From: David Howells
Date: Mon Nov 13 2017 - 11:29:23 EST

Hi Linus,

Could you pull my kAFS filesystem driver overhaul please?

Note that it is based on net-next/master and tip/timers/core and will need
pulling after both of those. There's a merge at the base of the branch
that effects this.

The major points of the overhaul are:

(1) Preliminary groundwork is laid for supporting network-namespacing of
kAFS. The remainder of the namespacing work requires some way to pass
namespace information to submounts triggered by an automount. This
requires something like the mount overhaul that's in progress.

(2) sockaddr_rxrpc is used in preference to in_addr for holding addresses
internally and add support for talking to the YFS VL server. With
this, kAFS can do everything over IPv6 as well as IPv4 if it's talking
to servers that support it.

(3) Callback handling is overhauled to be generally passive rather than
active. 'Callbacks' are promises by the server to tell us about data
and metadata changes. Callbacks are now checked when we next touch an
inode rather than actively going and looking for it where possible.

(4) File access permit caching is overhauled to store the caching
information per-inode rather than per-directory, shared over
subordinate files. Whilst older AFS servers only allow ACLs on
directories (shared to the files in that directory), newer AFS servers
break that restriction.

To improve memory usage and to make it easier to do mass-key removal,
permit combinations are cached and shared.

(5) Cell database management is overhauled to allow lighter locks to be
used and to make cell records autonomous state machines that look
after getting their own DNS records and cleaning themselves up, in
particular preventing races in acquiring and relinquishing the fscache
token for the cell.

(6) Volume caching is overhauled. The afs_vlocation record is got rid of
to simplify things and the superblock is now keyed on the cell and the
numeric volume ID only. The volume record is tied to a superblock and
normal superblock management is used to mediate the lifetime of the
volume fscache token.

(7) File server record caching is overhauled to make server records
independent of cells and volumes. A server can be in multiple cells
(in such a case, the administrator must make sure that the VL services
for all cells correctly reflect the volumes shared between those

Server records are now indexed using the UUID of the server rather
than the address since a server can have multiple addresses.

(8) File server rotation is overhauled to handle VMOVED, VBUSY (and
similar), VOFFLINE and VNOVOL indications and to handle rotation both
of servers and addresses of those servers. The rotation will also
wait and retry if the server says it is busy.

(9) Data writeback is overhauled. Each inode no longer stores a list of
modified sections tagged with the key that authorised it in favour of
noting the modified region of a page in page->private and storing a
list of keys that made modifications in the inode.

This simplifies things and allows other keys to be used to actually
write to the server if a key that made a modification becomes useless.

(10) Writable mmap() is implemented. This allows a kernel to be build
entirely on AFS.

Note that Pre AFS-3.4 servers are no longer supported, though this can be
added back if necessary (AFS-3.4 was released in 1998).

The following changes since commit 81445e63e67a1e98b1c2575fa2b406d4289d2754:

Merge remote-tracking branch 'tip/timers/core' into afs-next (2017-11-13 15:36:33 +0000)

are available in the git repository at:

git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git tags/afs-next-20171113

for you to fetch changes up to 98bf40cd99fcfed0705812b6cbdbb3b441a42970:

afs: Protect call->state changes against signals (2017-11-13 15:38:21 +0000)

AFS development

David Howells (34):
Pass mode to wait_on_atomic_t() action funcs and provide default actions
afs: Lay the groundwork for supporting network namespaces
afs: Close the rxrpc socket only after purging the servers
afs: Fix server reaping
afs: Note the cell in the superblock info also
afs: Push the net ns pointer to more places
afs: Add some protocol defs
afs: Update the cache index structure
afs: Keep and pass sockaddr_rxrpc addresses rather than in_addr
afs: Allow IPv6 address specification of VL servers
afs: Consolidate abort_to_error translators
afs: Condense afs_call's reply{,2,3,4} into an array
afs: Potentially return call->reply[0] from afs_make_call()
afs: Connect up the CB.ProbeUuid
afs: Fix the afs_uuid struct to make the char-sized fields signed
afs: Rename struct afs_call server member to cm_server
afs: Overhaul the callback handling
afs: Overhaul permit caching
afs: Overhaul cell database management
afs: Add an address list concept
afs: Move server rotation code into its own file
afs: Overhaul volume and server record caching and fileserver rotation
afs: Make use of the YFS service upgrade to fully support IPv6
afs: Only progress call state at end of Tx phase from rxrpc callback
afs: Fix total-length calculation for multiple-page send
afs: Fix documentation on # vs % prefix in mount source specification
afs: Trace the initiation and completion of client calls
afs: Trace the sending of pages
afs: Fix directory read/modify race
afs: Introduce a file-private data record
afs: Get rid of the afs_writeback record
afs: Implement shared-writeable mmap
afs: Trace page dirty/clean
afs: Protect call->state changes against signals

Marc Dionne (1):
afs: Use a dynamic port if 7001 is in use

Documentation/filesystems/afs.txt | 4 +-
arch/mips/kernel/traps.c | 14 +-
drivers/gpu/drm/drm_dp_aux_dev.c | 8 +-
drivers/gpu/drm/i915/selftests/intel_breadcrumbs.c | 10 +-
drivers/media/platform/qcom/venus/hfi.c | 8 +-
fs/afs/Makefile | 5 +-
fs/afs/addr_list.c | 381 ++++++++
fs/afs/afs.h | 35 +-
fs/afs/afs_fs.h | 6 +
fs/afs/afs_vl.h | 73 +-
fs/afs/cache.c | 239 +----
fs/afs/callback.c | 504 +++-------
fs/afs/cell.c | 887 +++++++++++------
fs/afs/cmservice.c | 77 +-
fs/afs/dir.c | 461 +++++----
fs/afs/file.c | 194 +++-
fs/afs/flock.c | 159 ++-
fs/afs/fsclient.c | 830 +++++++++-------
fs/afs/inode.c | 177 ++--
fs/afs/internal.h | 905 ++++++++++-------
fs/afs/main.c | 145 ++-
fs/afs/misc.c | 38 +-
fs/afs/proc.c | 247 +++--
fs/afs/rotate.c | 715 ++++++++++++++
fs/afs/rxrpc.c | 335 ++++---
fs/afs/security.c | 378 +++++---
fs/afs/server.c | 782 +++++++++++----
fs/afs/server_list.c | 153 +++
fs/afs/super.c | 190 ++--
fs/afs/vlclient.c | 682 ++++++++++---
fs/afs/vlocation.c | 720 --------------
fs/afs/vnode.c | 1025 --------------------
fs/afs/volume.c | 611 ++++++------
fs/afs/write.c | 709 ++++++++------
fs/afs/xattr.c | 4 +-
fs/btrfs/extent-tree.c | 27 +-
fs/fscache/cookie.c | 2 +-
fs/fscache/internal.h | 2 -
fs/fscache/main.c | 9 -
fs/nfs/inode.c | 4 +-
fs/nfs/internal.h | 2 +-
fs/ocfs2/filecheck.c | 8 +-
include/linux/wait_bit.h | 15 +-
include/trace/events/afs.h | 293 ++++++
include/uapi/linux/magic.h | 1 +
kernel/sched/wait_bit.c | 18 +-
mm/filemap.c | 1 +
47 files changed, 6769 insertions(+), 5324 deletions(-)
create mode 100644 fs/afs/addr_list.c
create mode 100644 fs/afs/rotate.c
create mode 100644 fs/afs/server_list.c
delete mode 100644 fs/afs/vlocation.c
delete mode 100644 fs/afs/vnode.c