firewire: core: implement variations to send request and wait for response with time stamp

In the previous commit, the core function of Linux FireWire subsystem
was changed for two cases to operate

firewire: core: implement variations to send request and wait for response with time stamp

In the previous commit, the core function of Linux FireWire subsystem
was changed for two cases to operate asynchronous transaction with or
without time stamp.

This commit changes kernel API for the two cases. Current kernel API,
fw_send_request(), is changed to be static inline function to call
__fw_send_request(), which receives two argument for union and flag of
callback function. The new kernel API, fw_send_request_with_tstamp() is
also added as static inline function, too. When calling, the two
arguments are copied to internal structure, then used in softIRQ
context.

Link: https://lore.kernel.org/r/20230529113406.986289-7-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>

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firewire: core: use union for callback of transaction completion

In 1394 OHCI, the OUTPUT_LAST descriptor of Asynchronous Transmit (AT)
request context has timeStamp field, in which 1394 OHCI contro

firewire: core: use union for callback of transaction completion

In 1394 OHCI, the OUTPUT_LAST descriptor of Asynchronous Transmit (AT)
request context has timeStamp field, in which 1394 OHCI controller
record the isochronous cycle when the packet was sent for the request
subaction. Additionally, for the case of split transaction in IEEE 1394,
Asynchronous Receive (AT) request context is used for response subaction
to finish the transaction. The trailer quadlet of descriptor in the
context has timeStamp field, in which 1394 OHCI controller records the
isochronous cycle when the packet arrived.

Current implementation of 1394 OHCI controller driver stores values of
both fields to internal structure as time stamp, while Linux FireWire
subsystem provides no way to access to it. When using asynchronous
transaction service provided by the subsystem, callback function is passed
to kernel API. The prototype of callback function has the lack of argument
for the values.

This commit adds a new callback function for the purpose. It has an
additional argument to point to the constant array with two elements. For
backward compatibility to kernel space, a new union is also adds to wrap
two different prototype of callback function. The fw_transaction structure
has the union as a member and a boolean flag to express which function
callback is available.

The core function is changed to handle the two cases; with or without
time stamp. For the error path to process transaction, the isochronous
cycle is computed by current value of CYCLE_TIMER register in 1394 OHCI
controller. Especially for the case of timeout of split transaction, the
expected isochronous cycle is computed.

Link: https://lore.kernel.org/r/20230529113406.986289-6-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>

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firewire: cdev: obsolete NULL check to detect IEC 61883-1 FCP region

In the character device, the listener to address space should distinguish
whether the request is to IEC 61883-1 FCP region or not

firewire: cdev: obsolete NULL check to detect IEC 61883-1 FCP region

In the character device, the listener to address space should distinguish
whether the request is to IEC 61883-1 FCP region or not. The user space
application needs to access to the object of request in enough later by
read(2), while the core function releases the object of request in the FCP
case after completing the callback to handler.

The handler guarantees the access safe by some way. It's done by
duplication of the object after NULL check to the request, since core
function passes NULL in the FCP case. It's inconvenient since the object
of request includes some helpful information. It's better to add another
way to check whether the request is to FCP region or not.

Conveniently the file of transaction layer includes local implementation
for the purpose. This commit moves it to module local file and use it
instead of the NULL check, then the result of check is stored to
per-client data for the inbound transaction so that the result can be
referred by later to release the data.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20230120090344.296451-3-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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firewire: core: use kref structure to maintain lifetime of data for fw_request structure

Developers have acknowledged that maintenance of lifetime for
fw_transaction structure is effective when hand

firewire: core: use kref structure to maintain lifetime of data for fw_request structure

Developers have acknowledged that maintenance of lifetime for
fw_transaction structure is effective when handling asynchronous
transaction to IEC 61883-1 FCP region, since the core function allows
multiples listeners to the region. Some of them needs to access to the
payload of request in process context after the callback to listener,
while the core function releases the object for the structure just after
completing the callbacks to listeners.

One of the listeners is character device. Current implementation of the
character device duplicates the object for the payload of transaction,
while it's a cost in kernel memory consumption. The lifetime management
can reduce it.

The typical way to maintain the lifetime is reference count. This commit
uses kref structure as a first step for the purpose.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20230120090344.296451-2-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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firewire: remove check of list iterator against head past the loop body

When list_for_each_entry() completes the iteration over the whole list
without breaking the loop, the iterator value will be a

firewire: remove check of list iterator against head past the loop body

When list_for_each_entry() completes the iteration over the whole list
without breaking the loop, the iterator value will be a bogus pointer
computed based on the head element.

While it is safe to use the pointer to determine if it was computed
based on the head element, either with list_entry_is_head() or
&pos->member == head, using the iterator variable after the loop should
be avoided.

In preparation to limit the scope of a list iterator to the list
traversal loop, use a dedicated pointer to point to the found element [1].

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1]
Cc: <stable@vger.kernel.org>
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20220409041243.603210-3-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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firewire: add kernel API to access packet structure in request structure for AR context

In 1394 OHCI specification, descriptor of Asynchronous Receive DMA context
has timeStamp field in its trailer

firewire: add kernel API to access packet structure in request structure for AR context

In 1394 OHCI specification, descriptor of Asynchronous Receive DMA context
has timeStamp field in its trailer quadlet. The field is written by
the host controller for the time to receive asynchronous request
subaction in isochronous cycle time.

In Linux FireWire subsystem, the value of field is stored to fw_packet
structure and copied to fw_request structure as the part. The fw_request
structure is hidden from unit driver and passed as opaque pointer when
calling registered handler. It's inconvenient to the unit driver which
needs timestamp of packet.

This commit adds kernel API to pick up timestamp from opaque pointer to
fw_request structure.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20220405072221.226217-4-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>

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firewire: remove check of list iterator against head past the loop body

commit 9423973869bd4632ffe669f950510c49296656e0 upstream.

When list_for_each_entry() completes the iteration over the whole l

firewire: remove check of list iterator against head past the loop body

commit 9423973869bd4632ffe669f950510c49296656e0 upstream.

When list_for_each_entry() completes the iteration over the whole list
without breaking the loop, the iterator value will be a bogus pointer
computed based on the head element.

While it is safe to use the pointer to determine if it was computed
based on the head element, either with list_entry_is_head() or
&pos->member == head, using the iterator variable after the loop should
be avoided.

In preparation to limit the scope of a list iterator to the list
traversal loop, use a dedicated pointer to point to the found element [1].

Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1]
Cc: <stable@vger.kernel.org>
Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20220409041243.603210-3-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through mar

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

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firewire: ohci: Replace zero-length array with flexible-array

There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Ke

firewire: ohci: Replace zero-length array with flexible-array

There is a regular need in the kernel to provide a way to declare having a
dynamically sized set of trailing elements in a structure. Kernel code should
always use “flexible array members”[1] for these cases. The older style of
one-element or zero-length arrays should no longer be used[2].

[1] https://en.wikipedia.org/wiki/Flexible_array_member
[2] https://github.com/KSPP/linux/issues/21

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of th

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details you
should have received a copy of the gnu general public license along
with this program if not write to the free software foundation inc
59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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FireWire: clean up core-transaction.c kernel-doc

Clean up kernel-doc warnings in <drivers/firewire/core-transaction.c>
so that it can be added to a Firewire/IEEE 1394 driver-api chapter
without addi

FireWire: clean up core-transaction.c kernel-doc

Clean up kernel-doc warnings in <drivers/firewire/core-transaction.c>
so that it can be added to a Firewire/IEEE 1394 driver-api chapter
without adding lots of noisy warnings to the documentation build.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Cc: linux-doc@vger.kernel.org
Cc: linux-scsi@vger.kernel.org
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

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timer: Remove init_timer_on_stack() in favor of timer_setup_on_stack()

Remove uses of init_timer_on_stack() with open-coded function and data
assignments that could be expressed using timer_setup_on

timer: Remove init_timer_on_stack() in favor of timer_setup_on_stack()

Remove uses of init_timer_on_stack() with open-coded function and data
assignments that could be expressed using timer_setup_on_stack(). Several
were removed from the stack entirely since there was a one-to-one mapping
of parent structure to timer, those are switched to using timer_setup()
instead. All related callbacks were adjusted to use from_timer().

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-mips@linux-mips.org
Cc: Petr Mladek <pmladek@suse.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Sebastian Reichel <sre@kernel.org>
Cc: Kalle Valo <kvalo@qca.qualcomm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: linux1394-devel@lists.sourceforge.net
Cc: Chris Metcalf <cmetcalf@mellanox.com>
Cc: linux-s390@vger.kernel.org
Cc: linux-wireless@vger.kernel.org
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: linux-scsi@vger.kernel.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Ursula Braun <ubraun@linux.vnet.ibm.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Harish Patil <harish.patil@cavium.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Michael Reed <mdr@sgi.com>
Cc: Manish Chopra <manish.chopra@cavium.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-pm@vger.kernel.org
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Julian Wiedmann <jwi@linux.vnet.ibm.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Mark Gross <mark.gross@intel.com>
Cc: linux-watchdog@vger.kernel.org
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: netdev@vger.kernel.org
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Link: https://lkml.kernel.org/r/1507159627-127660-4-git-send-email-keescook@chromium.org

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firewire: core: use correct vendor/model IDs

The kernel was using the vendor ID 0xd00d1e, which was inherited from
the old ieee1394 driver stack. However, this ID was not registered, and
invalid.

firewire: core: use correct vendor/model IDs

The kernel was using the vendor ID 0xd00d1e, which was inherited from
the old ieee1394 driver stack. However, this ID was not registered, and
invalid.

Instead, use the vendor/model IDs that are now officially assigned to
the kernel:
https://ieee1394.wiki.kernel.org/index.php/IEEE_OUI_Assignments

[stefanr:
- The vendor ID 001f11 is Openmoko, Inc.'s identifier, registered at
IEEE Registration Authority.
- The range of model IDs 023900...0239ff are the Linux kernel 1394
subsystem's identifiers, registered at Openmoko.
- Model ID 023901 is picked by the subsystem developers as
firewire-core's model ID.]

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

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firewire: Enable remote DMA above 4 GB

This makes all of a machine's memory accessible to remote debugging via
FireWire, using the physical response unit (i.e. RDMA) of OHCI-1394 link
layer controll

firewire: Enable remote DMA above 4 GB

This makes all of a machine's memory accessible to remote debugging via
FireWire, using the physical response unit (i.e. RDMA) of OHCI-1394 link
layer controllers.

This requires actual support by the controller. The only ones currently
known to support it are Agere/LSI FW643. Most if not all other OHCI-1394
controllers do not implement the optional Physical Upper Bound register.
With them, RDMA will continue to be limited to the lowermost 4 GB.

firewire-ohci's startup message in the kernel log is augmented to tell
whether the controller does expose more than 4 GB to RDMA.

While OHCI-1394 allows for a maximum Physical Upper Bound of
0xffff'0000'0000 (near 256 TB), this implementation sets it to
0x8000'0000'0000 (128 TB) in order to avoid interference with applications
that require interrupt-served asynchronous request reception at
respectively low addresses.

Note, this change does not switch remote DMA on. It only increases the
range of remote access to all memory (instead of just 4 GB) whenever
remote DMA was switched on by other means. The latter is achieved by
setting firewire-ohci's remote_dma parameter, or if the physical DMA
filter is opened through firewire-sbp2.

Derived from patch "firewire: Enable physical DMA above 4GB" by
Peter Hurley <peter@hurleysoftware.com> from March 27, 2013.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

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tree-wide: use reinit_completion instead of INIT_COMPLETION

Use this new function to make code more comprehensible, since we are
reinitialzing the completion, not initializing.

[akpm@linux-foundati

tree-wide: use reinit_completion instead of INIT_COMPLETION

Use this new function to make code more comprehensible, since we are
reinitialzing the completion, not initializing.

[akpm@linux-foundation.org: linux-next resyncs]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Linus Walleij <linus.walleij@linaro.org> (personally at LCE13)
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

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firewire: WQ_NON_REENTRANT is meaningless and going away

dbf2576e37 ("workqueue: make all workqueues non-reentrant") made
WQ_NON_REENTRANT no-op and the flag is going away. Remove its usages.

This

firewire: WQ_NON_REENTRANT is meaningless and going away

dbf2576e37 ("workqueue: make all workqueues non-reentrant") made
WQ_NON_REENTRANT no-op and the flag is going away. Remove its usages.

This patch doesn't introduce any behavior changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

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firewire: addendum to address handler RCU conversion

Follow up on commit c285f6ff6787 "firewire: remove global lock around
address handlers, convert to RCU":

- address_handler_lock no longer seri

firewire: addendum to address handler RCU conversion

Follow up on commit c285f6ff6787 "firewire: remove global lock around
address handlers, convert to RCU":

- address_handler_lock no longer serializes the address handler, only
its function to serialize updates to the list of handlers remains.
Rename the lock to address_handler_list_lock.

- Callers of fw_core_remove_address_handler() must be able to sleep.
Comment on this in the API documentation.

- The counterpart fw_core_add_address_handler() is by nature something
which is used in process context. Replace spin_lock_bh() by
spin_lock() in fw_core_add_address_handler() and in
fw_core_remove_address_handler(), and document that process context
is now required for fw_core_add_address_handler().

- Extend the documentation of fw_address_callback_t.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

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firewire: remove global lock around address handlers, convert to RCU

Upper-layer handlers for inbound requests were called with a spinlock
held by firewire-core. Calling into upper layers with a lo

firewire: remove global lock around address handlers, convert to RCU

Upper-layer handlers for inbound requests were called with a spinlock
held by firewire-core. Calling into upper layers with a lower layer
lock held is generally a bad idea.

What's more, since commit ea102d0ec475 "firewire: core: convert AR-req
handler lock from _irqsave to _bh", a caller of fw_send_request() i.e.
initiator of outbound request could no longer do that while having
interrupts disabled, if the local node was addressed by that request.

In order to make all this more flexible, convert the management of
address ranges and handlers from a global lock around readers and
writers to RCU (and a remaining global lock for writers). As a minor
side effect, handling of inbound requests at different cards and of
local requests is now no longer serialized. (There is still per-card
serialization of remote requests since firewire-ohci uses a single DMA
tasklet for inbound request events.)

In other words, address handlers are now called in an RCU read-side
critical section instead of from within a spin_lock_bh serialized
section.

(Changelog rewritten by Stefan R.)

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

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firewire: core: allocate the low memory region

Prevent userspace applications from allocating low memory address
ranges. Otherwise, if some application happens to allocate such
a range and intends

firewire: core: allocate the low memory region

Prevent userspace applications from allocating low memory address
ranges. Otherwise, if some application happens to allocate such
a range and intends for a remote node to access it, and if that node
also implements SBP-2 (which will become more likely with the upcoming
SBP-2 target support), these accesses would be routed by the physical
DMA unit to some wrong memory address.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

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firewire: Add function to get speed from opaque struct fw_request

Sometimes it's useful to know the FireWire speed of the request that has
just come in to a fw_address_handler callback. As struct fw

firewire: Add function to get speed from opaque struct fw_request

Sometimes it's useful to know the FireWire speed of the request that has
just come in to a fw_address_handler callback. As struct fw_request is
opaque we can't peek inside to get the speed out of the struct fw_packet
that's just inside. For example, the SBP-2 spec says:

"The speed at which the block write request to the MANAGEMENT_AGENT
register is received shall determine the speed used by the target for
all subsequent requests to read the initiator’s configuration ROM, fetch
ORB’s from initiator memory or store status at the initiator’s
status_FIFO. Command block ORB’s separately specify the speed for
requests addressed to the data buffer or page table."

[ ANSI T10/1155D Revision 4 page 53/54 ]

Signed-off-by: Chris Boot <bootc@bootc.net>
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

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firewire: move rcode_string() to core

There is nothing audio-specific about the rcode_string() helper, so move
it from snd-firewire-lib into firewire-core to allow other code to use it.

Signed-off-

firewire: move rcode_string() to core

There is nothing audio-specific about the rcode_string() helper, so move
it from snd-firewire-lib into firewire-core to allow other code to use it.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (fixed sound/firewire/cmp.c)

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firewire: core: convert AR-req handler lock from _irqsave to _bh

fw_core_handle_request() is called by the low-level driver in tasklet
context or process context, and fw_core_add/remove_address_hand

firewire: core: convert AR-req handler lock from _irqsave to _bh

fw_core_handle_request() is called by the low-level driver in tasklet
context or process context, and fw_core_add/remove_address_handler() is
called by mid- or high-level code in process context. So convert
address_handler_lock accesses from those which disable local IRQs to
ones which just disable local softIRQs.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

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firewire: core: fix race at address_handler unregistration

Fix the following unlikely but possible race:

CPU 1 CPU 2
----------------------------------------------------

firewire: core: fix race at address_handler unregistration

Fix the following unlikely but possible race:

CPU 1 CPU 2
------------------------------------------------------------------------
AR-request tasklet
lookup handler
unregister handler
free handler->callback_data or handler
call handler->callback

The application which registered the handler has no way to stop nodes
sending new requests to their address range, hence cannot prevent this
race.

Fix it simply by extending the address_handler_lock-protected region
from only around the lookup to around both lookup and call. We only
need to do so in the exclusive region handler; the FCP region handler
already holds the lock around the handler->callback call.

Alas this removes the current ability to execute the callback in
parallel on different CPUs if it was called for different FireWire cards
at the same time. (For a single card, the handler is already
serialized.) If this loss of a rather obscure feature is not tolerable,
a more complex fix would be required: Add a handler reference counter;
wait in fw_core_remove_address_handler() for this conter to become zero.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

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firewire: core: remove obsolete comment

Target-like applications or peer-to-peer-like applications require the
global address handler registration which we have right now, or a per-
card registratio

firewire: core: remove obsolete comment

Target-like applications or peer-to-peer-like applications require the
global address handler registration which we have right now, or a per-
card registration. And node lookup, while it would be nice to have,
would be impossible in the brief time between self-ID-complete event and
completion of firewire-core's topology scanning.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

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firewire: core: prefix log messages with card name

Associate all log messages from firewire-core with the respective card
because some people have more than one card. E.g.
firewire_ohci 0000:04

firewire: core: prefix log messages with card name

Associate all log messages from firewire-core with the respective card
because some people have more than one card. E.g.
firewire_ohci 0000:04:00.0: added OHCI v1.10 device as card 0, 8 IR + 8 IT contexts, quirks 0x0
firewire_ohci 0000:05:00.0: added OHCI v1.10 device as card 1, 8 IR + 8 IT contexts, quirks 0x0
firewire_core: created device fw0: GUID 0814438400000389, S800
firewire_core: phy config: new root=ffc1, gap_count=5
firewire_core: created device fw1: GUID 0814438400000388, S800
firewire_core: created device fw2: GUID 0001d202e06800d1, S800
turns into
firewire_ohci 0000:04:00.0: added OHCI v1.10 device as card 0, 8 IR + 8 IT contexts, quirks 0x0
firewire_ohci 0000:05:00.0: added OHCI v1.10 device as card 1, 8 IR + 8 IT contexts, quirks 0x0
firewire_core 0000:04:00.0: created device fw0: GUID 0814438400000389, S800
firewire_core 0000:04:00.0: phy config: new root=ffc1, gap_count=5
firewire_core 0000:05:00.0: created device fw1: GUID 0814438400000388, S800
firewire_core 0000:04:00.0: created device fw2: GUID 0001d202e06800d1, S800

This increases the module size slightly; to keep this in check, turn the
former printk wrapper macros into functions. Their implementation is
largely copied from driver core's dev_printk counterparts.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

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