nfsd4: reorganize write decoding

In preparation for moving some of it elsewhere.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
nfsd4: move more write parameters into xdr argument

In preparation for moving some of this elsewhere.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
nfsd4: delay filling in write iovec array till after xdr decoding

Our server rejects compounds containing more than one write operation.
It's unclear whether this is really permitted by the spec; with 4.0,
it's possibly OK, with 4.1 (which has clearer limits on compound
parameters), it's probably not OK.  No client that we're aware of has
ever done this, but in theory it could be useful.

The source of the limitation: we need an array of iovecs to pass to the
write operation.  In the worst case that array of iovecs could have
hundreds of elements (the maximum rwsize divided by the page size), so
it's too big to put on the stack, or in each compound op.  So we instead
keep a single such array in the compound argument.

We fill in that array at the time we decode the xdr operation.

But we decode every op in the compound before executing any of them.  So
once we've used that array we can't decode another write.

If we instead delay filling in that array till the time we actually
perform the write, we can reuse it.

Another option might be to switch to decoding compound ops one at a
time.  I considered doing that, but it has a number of other side
effects, and I'd rather fix just this one problem for now.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
nfsd4: downgrade some fs/nfsd/nfs4state.c BUG's

Linus has pointed out that indiscriminate use of BUG's can make it
harder to diagnose bugs because they can bring a machine down, often
before we manage to get any useful debugging information to the logs.
(Consider, for example, a BUG() that fires in a workqueue, or while
holding a spinlock).

Most of these BUG's won't do much more than kill an nfsd thread, but it
would still probably be safer to get out the warning without dying.

There's still more of this to do in nfsd/.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
nfsd4: return badname, not inval, on "." or "..", or "/"

The spec requires badname, not inval, in these cases.

Some callers want us to return enoent, but I can see no justification
for that.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
ARM64: dma_debug: add debug_dma_mapping_error support

Add dma-debug interface debug_dma_mapping_error() to debug drivers that fail
to check dma mapping errors on addresses returned by dma_map_single() and
dma_map_page() interfaces.

Signed-off-by: Shuah Khan <shuah.khan@hp.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
c6x: dma_debug: add debug_dma_mapping_error support

Add dma-debug interface debug_dma_mapping_error() to debug drivers that fail
to check dma mapping errors on addresses returned by dma_map_single() and
dma_map_page() interfaces.

Signed-off-by: Shuah Khan <shuah.khan@hp.com>
Acked-by: Mark Salter <msalter@redhat.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
ia64: dma_debug: add debug_dma_mapping_error support

Add dma-debug interface debug_dma_mapping_error() to debug drivers that fail
to check dma mapping errors on addresses returned by dma_map_single() and
dma_map_page() interfaces.

Signed-off-by: Shuah Khan <shuah.khan@hp.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
microblaze: dma-mapping: support debug_dma_mapping_error

Add support for debug_dma_mapping_error() call to avoid warning from
debug_dma_unmap() interface when it checks for mapping error checked
status. Without this patch, device driver failed to check map error
warning is generated.

Signed-off-by: Shuah Khan <shuah.khan@hp.com>
Acked-by: Michal Simek <monstr@monstr.eu>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
mips: dma_debug: add debug_dma_mapping_error support

Add dma-debug interface debug_dma_mapping_error() to debug drivers that fail
to check dma mapping errors on addresses returned by dma_map_single() and
dma_map_page() interfaces.

Signed-off-by: Shuah Khan <shuah.khan@hp.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
powerpc: dma_debug: add debug_dma_mapping_error support

Add dma-debug interface debug_dma_mapping_error() to debug drivers that fail
to check dma mapping errors on addresses returned by dma_map_single() and
dma_map_page() interfaces.

Signed-off-by: Shuah Khan <shuah.khan@hp.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
sh: dma_debug: add debug_dma_mapping_error support

Add dma-debug interface debug_dma_mapping_error() to debug drivers that fail
to check dma mapping errors on addresses returned by dma_map_single() and
dma_map_page() interfaces.

Signed-off-by: Shuah Khan <shuah.khan@hp.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
tile: dma_debug: add debug_dma_mapping_error support

Add dma-debug interface debug_dma_mapping_error() to debug drivers that fail
to check dma mapping errors on addresses returned by dma_map_single() and
dma_map_page() interfaces.

Signed-off-by: Shuah Khan <shuah.khan@hp.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
iommu/tegra: smmu: Remove unnecessary PTC/TLB flush all

smmu_flush_regs() does TLB/PTC flush all when freeing a second level
page table. This isn't necessay at all since each pte entry has been
already maintained by address in the above flush_ptc_and_tlb().

Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
iommu/tegra: gart: Move bus_set_iommu after probe for multi arch

For a single image to support multiple SoCs(GART/SMMU).

Reported-by: Arto Merilainen <amerilainen@nvidia.com>
Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
iommu/tegra: smmu: Move bus_set_iommu after probe for multi arch

For a single image to support multiple SoCs(GART/SMMU).

Reported-by: Arto Merilainen <amerilainen@nvidia.com>
Signed-off-by: Hiroshi Doyu <hdoyu@nvidia.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
nfsd4: remove state lock from nfsd4_load_reboot_recovery_data

That function is only called under nfsd_mutex: we know that because the
only caller is nfsd_svc, via

        nfsd_svc
          nfsd_startup
            nfs4_state_start
              nfsd4_client_tracking_init
                client_tracking_ops->init == nfsd4_load_reboot_recovery_data

The shared state accessed here includes:

        - user_recovery_dirname: used here, modified only by
          nfs4_reset_recoverydir, which can be verified to only be
          called under nfsd_mutex.
        - filesystem state, protected by i_mutex (handwaving slightly
	  here)
        - rec_file, reclaim_str_hashtbl, reclaim_str_hashtbl_size: other
          than here, used only from code called from nfsd or laundromat
          threads, both of which should be started only after this runs
          (see nfsd_svc) and stopped before this could run again (see
          nfsd_shutdown, called from nfsd_last_thread).

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
nfsd4: remove state lock from nfs4_state_shutdown

Protection of __nfs4_state_shutdown() with nfs4_lock_state() looks redundant.

This function is called by the last NFSd thread on it's exit and state lock
protects actually two functions (del_recall_lru is protected by recall_lock):
1) nfsd4_client_tracking_exit
2) __nfs4_state_shutdown_net

"nfsd4_client_tracking_exit" doesn't require state lock protection, because it's
state can be modified only by tracker callbacks.
Here a re they:
1) create: is called only from nfsd4_proc_compound.
2) remove: is called from either nfsd4_proc_compound or nfs4_laundromat.
3) check: is called only from nfsd4_proc_compound.
4) grace_done; called only from nfs4_laundromat.

nfsd4_proc_compound is called onll by NFSd kthread, which is exiting right
now.
nfs4_laundromat is called by laundry_wq. But laundromat_work was canceled
already.

"__nfs4_state_shutdown_net" also doesn't require state lock protection,
because all NFSd kthreads are dead, and no race can happen with NFSd start,
because "nfsd_up" flag is still set.
Moreover, all Nfsd shutdown is protected with global nfsd_mutex.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
nfsd: make client_lock per net

This lock protects the client lru list and session hash table, which are
allocated per network namespace already.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
nfsd: make delegations shutdown network namespace aware

NFSv4 delegations are stored in global list. But they are nfs4_client
dependent, which is network namespace aware already.
State shutdown and laundromat are done per network namespace as well.
So, delegations unhash have to be done in network namespace context.

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>