dlm: move lkb xarray lookup out of lock

This patch moves the xarray lookup functionality for the lkb out of the
ls_lkbxa_lock read lock handling. We can do that as the xarray should be
possible to a

dlm: move lkb xarray lookup out of lock

This patch moves the xarray lookup functionality for the lkb out of the
ls_lkbxa_lock read lock handling. We can do that as the xarray should be
possible to access lockless in case of reader like xa_load(). We confirm
under ls_lkbxa_lock that the lkb is still part of the data structure and
take a reference when its still part of ls_lkbxa to avoid being freed
after doing the lookup. To do a check if the lkb is still part of the
ls_lkbxa data structure we use a kref_read() as the last put will remove
it from the ls_lkbxa data structure and any reference taken means it is
still part of ls_lkbxa.

A similar approach was done with the DLM rsb rhashtable just with a flag
instead of the refcounter because the refcounter has a slightly
different meaning.

Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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dlm: cleanup memory allocation helpers

This patch removes a unnecessary parameter from DLM memory allocation
helpers and reduce some functions by just directly reply the pointer
address of the alloc

dlm: cleanup memory allocation helpers

This patch removes a unnecessary parameter from DLM memory allocation
helpers and reduce some functions by just directly reply the pointer
address of the allocated memory.

Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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dlm: add rcu_barrier before destroy kmem cache

In the case we trigger dlm_free_rsb() that does a call_rcu() and the
responding kfree() of res_lvbptr and a kmem_cache_free() of the rsb
pointer we nee

dlm: add rcu_barrier before destroy kmem cache

In the case we trigger dlm_free_rsb() that does a call_rcu() and the
responding kfree() of res_lvbptr and a kmem_cache_free() of the rsb
pointer we need to wait until this pending operation is done before
calling kmem_cache_destroy(). We doing that by using rcu_barrier() that
waits until all pending call_rcu() are done. This avoids that
kmem_cache_destroy() complains about active objects around that are not
being freed yet by call_rcu().

There is currently more discussions about to make this behaviour better,
see:

https://lore.kernel.org/netdev/[email protected]/

However this is only for call_rcu() if the callback calls
kmem_cache_destroy() only to replace it by kfree_rcu() call which has
currently some issue. This isn't our case because we also free the
res_lvbptr if being set.

For our case, to avoid the above race rcu_barrier() should be used before
calling kmem_cache_destroy() to be sure that there are no active objects
around. This is exactly what net/batman-adv is also doing before calling their
kmem_cache_destroy() in module unloading.

Fixes: 01fdeca1cc2d ("dlm: use rcu to avoid an extra rsb struct lookup")
Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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dlm: use rcu to avoid an extra rsb struct lookup

Use rcu to free rsb structs, and hold the rcu read lock
while looking up rsb structs. This allows us to avoid an
extra hash table lookup for an rsb.

dlm: use rcu to avoid an extra rsb struct lookup

Use rcu to free rsb structs, and hold the rcu read lock
while looking up rsb structs. This allows us to avoid an
extra hash table lookup for an rsb. A new rsb flag HASHED
is added which is set while the rsb is in the hash table.
This flag is checked in place of repeating the hash table
lookup.

Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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dlm: switch to GFP_ATOMIC in dlm allocations

Replace GFP_NOFS with GFP_ATOMIC. Also stop using idr_preload which
uses a non-bh spin_lock. This is further preparation for softirq
message processing

dlm: switch to GFP_ATOMIC in dlm allocations

Replace GFP_NOFS with GFP_ATOMIC. Also stop using idr_preload which
uses a non-bh spin_lock. This is further preparation for softirq
message processing.

Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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dlm: remove allocation parameter in msg allocation

Remove the context parameter for message allocations and
always use GFP_ATOMIC. This prepares for softirq message
processing.

Signed-off-by: Alexa

dlm: remove allocation parameter in msg allocation

Remove the context parameter for message allocations and
always use GFP_ATOMIC. This prepares for softirq message
processing.

Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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dlm: remove callback reference counting

Get rid of the unnecessary refcounting on callback structs.
Copy interesting callback info into the lkb struct rather
than maintaining pointers to callback st

dlm: remove callback reference counting

Get rid of the unnecessary refcounting on callback structs.
Copy interesting callback info into the lkb struct rather
than maintaining pointers to callback structs from the lkb.
This goes back to the way things were done prior to
commit 61bed0baa4db ("fs: dlm: use a non-static queue for callbacks").

Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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fs: dlm: change dflags to use atomic bits

Currently manipulating lkb_dflags assumes to held the rsb lock assigned
to the lkb. This is held by dlm message processing after certain
time to lookup the

fs: dlm: change dflags to use atomic bits

Currently manipulating lkb_dflags assumes to held the rsb lock assigned
to the lkb. This is held by dlm message processing after certain
time to lookup the right rsb from the received lkb message id. For user
space locks flags, which is currently the only use case for lkb_dflags,
flags are also being set during dlm character device handling without
holding the rsb lock. To minimize the risk that bit operations are
getting corrupted we switch to atomic bit operations. This patch will
also introduce helpers to snapshot atomic bit values in an non atomic
way. There might be still issues with the flag handling e.g. running in
case of manipulating bit ops and snapshot them at the same time, but this
patch minimize them and will start to use atomic bit operations.

Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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fs: dlm: store lkb distributed flags into own value

This patch stores lkb distributed flags value in an separate value
instead of sharing internal and distributed flags in lkb->lkb_flags value.
This

fs: dlm: store lkb distributed flags into own value

This patch stores lkb distributed flags value in an separate value
instead of sharing internal and distributed flags in lkb->lkb_flags value.
This has the advantage to not mask/write back flag values in
receive_flags() functionality. The dlm debug_fs does not provide the
distributed flags anymore, those can be added in future.

Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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fs: dlm: fix return value check in dlm_memory_init()

It should check 'cb_cache', after calling kmem_cache_create("dlm_cb").

Fixes: 61bed0baa4db ("fs: dlm: use a non-static queue for callbacks")
Sig

fs: dlm: fix return value check in dlm_memory_init()

It should check 'cb_cache', after calling kmem_cache_create("dlm_cb").

Fixes: 61bed0baa4db ("fs: dlm: use a non-static queue for callbacks")
Signed-off-by: Yang Yingliang <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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fs: dlm: allow different allocation context per _create_message

This patch allows to give the use control about the allocation context
based on a per message basis. Currently all messages forced to

fs: dlm: allow different allocation context per _create_message

This patch allows to give the use control about the allocation context
based on a per message basis. Currently all messages forced to be
created under GFP_NOFS context.

Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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fs: dlm: use a non-static queue for callbacks

This patch will introducde a queue implementation for callbacks by using
the Linux lists. The current callback queue handling is implemented by a
static

fs: dlm: use a non-static queue for callbacks

This patch will introducde a queue implementation for callbacks by using
the Linux lists. The current callback queue handling is implemented by a
static limit of 6 entries, see DLM_CALLBACKS_SIZE. The sequence number
inside the callback structure was used to see if the entries inside the
static entry is valid or not. We don't need any sequence numbers anymore
with a dynamic datastructure with grows and shrinks during runtime to
offer such functionality.

We assume that every callback will be delivered to the DLM user if once
queued. Therefore the callback flag DLM_CB_SKIP was dropped and the
check for skipping bast was moved before worker handling and not skip
while the callback worker executes. This will reduce unnecessary queues
of the callback worker.

All last callback saves are pointers now and don't need to copied over.
There is a reference counter for callback structures which will care
about to free the callback structures at the right time if they are not
referenced anymore.

Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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fs: dlm: memory cache for lowcomms hotpath

This patch introduces a kmem cache for dlm_msg handles which are used
always if dlm sends a message out. Even if their are covered by midcomms
layer or not

fs: dlm: memory cache for lowcomms hotpath

This patch introduces a kmem cache for dlm_msg handles which are used
always if dlm sends a message out. Even if their are covered by midcomms
layer or not.

Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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fs: dlm: memory cache for writequeue_entry

This patch introduces a kmem cache for writequeue entry. A writequeue
entry get quite a lot allocated if dlm transmit messages.

Signed-off-by: Alexander A

fs: dlm: memory cache for writequeue_entry

This patch introduces a kmem cache for writequeue entry. A writequeue
entry get quite a lot allocated if dlm transmit messages.

Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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fs: dlm: memory cache for midcomms hotpath

This patch will introduce a kmem cache for allocating message handles
which are needed for midcomms layer to take track of lowcomms messages.

Signed-off-b

fs: dlm: memory cache for midcomms hotpath

This patch will introduce a kmem cache for allocating message handles
which are needed for midcomms layer to take track of lowcomms messages.

Signed-off-by: Alexander Aring <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 193

Based on 1 normalized pattern(s):

this copyrighted material is made available to anyone wishing to use
modify copy or redistri

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 193

Based on 1 normalized pattern(s):

this copyrighted material is made available to anyone wishing to use
modify copy or redistribute it subject to the terms and conditions
of the gnu general public license v 2

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 45 file(s).

Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Richard Fontana <[email protected]>
Reviewed-by: Allison Randal <[email protected]>
Reviewed-by: Steve Winslow <[email protected]>
Reviewed-by: Alexios Zavras <[email protected]>
Cc: [email protected]
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

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dlm: NULL check before kmem_cache_destroy is not needed

kmem_cache_destroy(NULL) is safe, so removes NULL check before
freeing the mem. This patch also fix ifnullfree.cocci warnings.

Signed-off-by:

dlm: NULL check before kmem_cache_destroy is not needed

kmem_cache_destroy(NULL) is safe, so removes NULL check before
freeing the mem. This patch also fix ifnullfree.cocci warnings.

Signed-off-by: Wen Yang <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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dlm: NULL dereference on failure in kmem_cache_create()

We aren't allowed to pass NULL pointers to kmem_cache_destroy() so if
both allocations fail, it leads to a NULL dereference.

Signed-off-by: D

dlm: NULL dereference on failure in kmem_cache_create()

We aren't allowed to pass NULL pointers to kmem_cache_destroy() so if
both allocations fail, it leads to a NULL dereference.

Signed-off-by: Dan Carpenter <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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dlm: improve rsb searches

By pre-allocating rsb structs before searching the hash
table, they can be inserted immediately. This avoids
always having to repeat the search when adding the struct
to h

dlm: improve rsb searches

By pre-allocating rsb structs before searching the hash
table, they can be inserted immediately. This avoids
always having to repeat the search when adding the struct
to hash list.

This also adds space to the rsb struct for a max resource
name, so an rsb allocation can be used by any request.
The constant size also allows us to finally use a slab
for the rsb structs.

Signed-off-by: David Teigland <[email protected]>

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dlm: always use GFP_NOFS

Replace all GFP_KERNEL and ls_allocation with GFP_NOFS.
ls_allocation would be GFP_KERNEL for userland lockspaces
and GFP_NOFS for file system lockspaces.

It was discovered

dlm: always use GFP_NOFS

Replace all GFP_KERNEL and ls_allocation with GFP_NOFS.
ls_allocation would be GFP_KERNEL for userland lockspaces
and GFP_NOFS for file system lockspaces.

It was discovered that any lockspaces on the system can
affect all others by triggering memory reclaim in the
file system which could in turn call back into the dlm
to acquire locks, deadlocking dlm threads that were
shared by all lockspaces, like dlm_recv.

Signed-off-by: David Teigland <[email protected]>

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dlm: fix up memory allocation flags

Use ls_allocation for memory allocations, which a cluster fs sets to
GFP_NOFS. Use GFP_NOFS for allocations when no lockspace struct is
available. Taking dlm lo

dlm: fix up memory allocation flags

Use ls_allocation for memory allocations, which a cluster fs sets to
GFP_NOFS. Use GFP_NOFS for allocations when no lockspace struct is
available. Taking dlm locks needs to avoid calling back into the
cluster fs because write-out can require taking dlm locks.

Cc: Christine Caulfield <[email protected]>
Signed-off-by: Steven Whitehouse <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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dlm: add __init and __exit marks to init and exit functions

it moves 365 bytes from .text to .init.text, and 30 bytes from .text to
.exit.text, saves memory.

Signed-off-by: Denis Cheng <crquan@gmai

dlm: add __init and __exit marks to init and exit functions

it moves 365 bytes from .text to .init.text, and 30 bytes from .text to
.exit.text, saves memory.

Signed-off-by: Denis Cheng <[email protected]>
Signed-off-by: David Teigland <[email protected]>

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dlm: eliminate astparam type casting

Put lkb_astparam in a union with a dlm_user_args pointer to
eliminate a lot of type casting.

Signed-off-by: David Teigland <[email protected]>

dlm: use dlm prefix on alloc and free functions

The dlm functions in memory.c should use the dlm_ prefix. Also, use
kzalloc/kfree directly for dlm_direntry's, removing the wrapper functions.

Signe

dlm: use dlm prefix on alloc and free functions

The dlm functions in memory.c should use the dlm_ prefix. Also, use
kzalloc/kfree directly for dlm_direntry's, removing the wrapper functions.

Signed-off-by: David Teigland <[email protected]>

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mm: Remove slab destructors from kmem_cache_create().

Slab destructors were no longer supported after Christoph's
c59def9f222d44bb7e2f0a559f2906191a0862d7 change. They've been
BUGs for both slab and

mm: Remove slab destructors from kmem_cache_create().

Slab destructors were no longer supported after Christoph's
c59def9f222d44bb7e2f0a559f2906191a0862d7 change. They've been
BUGs for both slab and slub, and slob never supported them
either.

This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).

Signed-off-by: Paul Mundt <[email protected]>

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