Commit 22660db892 turned fw_iso_buffer_map_vma into a one-liner.
There is no need to keep this in the core-iso.c collection of buffer
management functions; put it inline into the sole user, the character
device file driver.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
In preparation to enabling -Wimplicit-fallthrough, mark switch
cases where we are expecting to fall through.
This patch fixes the following warnings:
drivers/firewire/core-device.c: In function ‘set_broadcast_channel’:
drivers/firewire/core-device.c:969:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
if (data & cpu_to_be32(1 << 31)) {
^
drivers/firewire/core-device.c:974:3: note: here
case RCODE_ADDRESS_ERROR:
^~~~
drivers/firewire/core-iso.c: In function ‘manage_channel’:
drivers/firewire/core-iso.c:308:7: warning: this statement may fall through [-Wimplicit-fallthrough=]
if ((data[0] & bit) == (data[1] & bit))
^
drivers/firewire/core-iso.c:312:3: note: here
default:
^~~~~~~
drivers/firewire/core-topology.c: In function ‘count_ports’:
drivers/firewire/core-topology.c:69:23: warning: this statement may fall through [-Wimplicit-fallthrough=]
(*child_port_count)++;
~~~~~~~~~~~~~~~~~~~^~
drivers/firewire/core-topology.c:70:3: note: here
case SELFID_PORT_PARENT:
^~~~
Warning level 3 was used: -Wimplicit-fallthrough=3
Notice that in some cases, the code comment is modified in
accordance with what GCC is expecting to find.
This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.
Cc: Kees Cook <keescook@chromium.org>
Cc: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (reworded a comment)
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
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>
Convert to use vm_map_pages_zero() to map range of kernel memory to user
vma.
This driver has ignored vm_pgoff and mapped the entire pages. We could
later "fix" these drivers to behave according to the normal vm_pgoff
offsetting simply by removing the _zero suffix on the function name and if
that causes regressions, it gives us an easy way to revert.
Link: http://lkml.kernel.org/r/88645f5ea8202784a8baaf389e592aeb8c505e8e.1552921225.git.jrdr.linux@gmail.com
Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Cc: Pawel Osciak <pawel@osciak.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sandy Huang <hjc@rock-chips.com>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Clean up kernel-doc warnings in <drivers/firewire/core-iso.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>
With a 32-bit i, computing i<<PAGE_SHIFT might result in
an overflow and in an eventual sign-extension.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Seen with recent libdc1394: If a client mmap()s the buffer of an
isochronous reception buffer with PROT_READ|PROT_WRITE instead of just
PROT_READ, firewire-core sets the wrong DMA mapping direction during
buffer initialization.
The fix is to split fw_iso_buffer_init() into allocation and DMA mapping
and to perform the latter after both buffer and DMA context were
allocated. Buffer allocation and context allocation may happen in any
order, but we need the context type (reception or transmission) in order
to set the DMA direction of the buffer.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
- Some SBP-2 initiator fixes, side product from ongoing work on a target.
- Reintroduction of an isochronous I/O feature of the older ieee1394 driver
stack (flush buffer completions); it was evidently rarely used but not
actually unused. Matching libraw1394 code is already available.
- Be sure to prefix all kernel log messages with device name or card name,
and other logging related cleanups.
- Misc other small cleanups, among them a small API change that affects
sound/firewire/ too.
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Merge tag 'firewire-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394
Pull IEEE 1394 (FireWire) subsystem updates post v3.3 from Stefan Richter:
- Some SBP-2 initiator fixes, side product from ongoing work on a target.
- Reintroduction of an isochronous I/O feature of the older ieee1394 driver
stack (flush buffer completions); it was evidently rarely used but not
actually unused. Matching libraw1394 code is already available.
- Be sure to prefix all kernel log messages with device name or card name,
and other logging related cleanups.
- Misc other small cleanups, among them a small API change that affects
sound/firewire/ too. Clemens Ladisch is aware of it.
* tag 'firewire-updates' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394: (26 commits)
firewire: allow explicit flushing of iso packet completions
firewire: prevent dropping of completed iso packet header data
firewire: ohci: factor out iso completion flushing code
firewire: ohci: simplify iso header pointer arithmetic
firewire: ohci: optimize control bit checks
firewire: ohci: remove unused excess_bytes field
firewire: ohci: copy_iso_headers(): make comment match the code
firewire: cdev: fix IR multichannel event documentation
firewire: ohci: fix too-early completion of IR multichannel buffers
firewire: ohci: move runtime debug facility out of #ifdef
firewire: tone down some diagnostic log messages
firewire: sbp2: replace a GFP_ATOMIC allocation
firewire: sbp2: Fix SCSI sense data mangling
firewire: sbp2: Ignore SBP-2 targets on the local node
firewire: sbp2: Take into account Unit_Unique_ID
firewire: nosy: Use the macro DMA_BIT_MASK().
firewire: core: convert AR-req handler lock from _irqsave to _bh
firewire: core: fix race at address_handler unregistration
firewire: core: remove obsolete comment
firewire: core: prefix log messages with card name
...
Extend the kernel and userspace APIs to allow reporting all currently
completed isochronous packets, even if the next interrupt packet has not
yet been reached. This is required to determine the status of the
packets at the end of a paused or stopped stream, and useful for more
precise synchronization of audio streams.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Ensure that the EXPORT_SYMBOL macros are present for when we clean up
the "module.h" is everywhere situation, to prevent build failures.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
When queueing iso packets, the run time is dominated by the two
MMIO accesses that set the DMA context's wake bit. Because most
drivers submit packets in batches, we can save much time by
removing all but the last wakeup.
The internal kernel API is changed to require a call to
fw_iso_context_queue_flush() after a batch of queued packets.
The user space API does not change, so one call to
FW_CDEV_IOC_QUEUE_ISO must specify multiple packets to take
advantage of this optimization.
In my measurements, this patch reduces the time needed to queue
fifty skip packets from userspace to one sixth on a 2.5 GHz CPU,
or to one third at 800 MHz.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
We do not need slab allocations anymore in order to satisfy
streaming DMA mapping constraints, thanks to commit da28947e7e
"firewire: ohci: avoid separate DMA mapping for small AT payloads".
(Besides, the slab-allocated buffers that firewire-core, firewire-sbp2,
and firedtv used to provide for 8-byte write and lock requests were
still not fully portable since they crossed cacheline boundaries or
shared a cacheline with unrelated CPU-accessed data. snd-firewire-lib
got this aspect right by using an extra kmalloc/ kfree just for the
8-byte transaction buffer.)
This change replaces kmalloc'ed lock transaction scratch buffers in
firewire-core, firedtv, and snd-firewire-lib by local stack allocations.
Perhaps the most notable result of the change is simpler locking because
there is no need to serialize usages of preallocated per-device buffers
anymore. Also, allocations and deallocations are simpler.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
firewire: core: ignore link-active bit of new nodes, fix device recognition
firewire: sbp2: revert obsolete 'fix stall with "Unsolicited response"'
firewire: core: increase default SPLIT_TIMEOUT value
firewire: ohci: Misleading kfree in ohci.c::pci_probe/remove
firewire: ohci: omit IntEvent.busReset check rom AT queueing
firewire: ohci: prevent starting of iso contexts with empty queue
firewire: ohci: prevent iso completion callbacks after context stop
firewire: core: rename some variables
firewire: nosy: should work on Power Mac G4 PCI too
firewire: core: fix card->reset_jiffies overflow
firewire: cdev: remove unneeded reference
firewire: cdev: always wait for outbound transactions to complete
firewire: cdev: remove unneeded idr_find() from complete_transaction()
firewire: ohci: log dead DMA contexts
Add a driver for two playback-only FireWire devices based on the OXFW970
chip.
v2: better AMDTP API abstraction; fix fw_unit leak; small fixes
v3: cache the iPCR value
v4: FireWave constraints; fix fw_device reference counting;
fix PCR caching; small changes and fixes
v5: volume/mute support; fix crashing due to pcm stop races
v6: fix build; one-channel volume for LaCie
v7: use signed values to make volume (range checks) work; fix function
block IDs for volume/mute; always use channel 0 for LaCie volume
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Tested-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
In manage_channel(), rename the variables "c" and "i" to the more
expressive "bit" and "channel".
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Conflicts:
drivers/firewire/core-card.c
drivers/firewire/core-cdev.c
and forgotten #include <linux/time.h> in drivers/firewire/ohci.c
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This adds the DMA context programming and userspace ABI for multichannel
reception, i.e. for listening on multiple channel numbers by means of a
single DMA context.
The use case is reception of more streams than there are IR DMA units
offered by the link layer. This is already implemented by the older
ohci1394 + ieee1394 + raw1394 stack. And as discussed recently on
linux1394-devel, this feature is occasionally used in practice.
The big drawbacks of this mode are that buffer layout and interrupt
generation necessarily differ from single-channel reception: Headers
and trailers are not stripped from packets, packets are not aligned with
buffer chunks, interrupts are per buffer chunk, not per packet.
These drawbacks also cause a rather hefty code footprint to support this
rarely used OHCI-1394 feature. (367 lines added, among them 94 lines of
added userspace ABI documentation.)
This implementation enforces that a multichannel reception context may
only listen to channels to which no single-channel context on the same
link layer is presently listening to. OHCI-1394 would allow to overlay
single-channel contexts by the multi-channel context, but this would be
a departure from the present first-come-first-served policy of IR
context creation.
The implementation is heavily based on an earlier one by Jay Fenlason.
Thanks Jay.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The present inline documentation of the fw_send_request() in-kernel API
refers to userland code that is not applicable to kernel drivers at all.
Reported-by: Ben Gamari <bgamari.foss@gmail.com>
While we are at fixing the whole documentation of fw_send_request(),
also improve the rest of firewire-core's kerneldoc comments:
- Add a bit of text concerning fw_run_transaction()'s call parameters.
- Append () to function names and tab-align parameter descriptions as
suggested by the example in Documentation/kernel-doc-nano-HOWTO.txt.
- Remove kerneldoc markers from comments on static functions.
- Remove outdated parameter descriptions at build_tree().
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
firewire: ohci: wait for local CSR lock access to finish
firewire: ohci: prevent aliasing of locally handled register addresses
firewire: core: fw_iso_resource_manage: return -EBUSY when out of resources
firewire: core: fix retries calculation in iso manage_channel()
firewire: cdev: fix cut+paste mistake in disclaimer
Returning -EIO for all errors would not allow clients to determine if
the resource allocation process itself failed, or if the resources are
not available. (The latter information is needed by CMP to synchronize
restoring of overlayed connections after a bus reset.)
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
If there is a permanent error condition when communicating with the IRM,
after the sixth error, the retry variable will be decremented to -1.
If, in this case, the bits in channels_mask are not yet exhausted, the
next channel is retried 2^32 times.
To fix this, check that retry is never decremented beyond zero.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.
percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.
http://userweb.kernel.org/~tj/misc/slabh-sweep.py
The script does the followings.
* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.
* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.
* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.
The conversion was done in the following steps.
1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.
2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.
3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.
4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.
5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.
6. percpu.h was updated not to include slab.h.
7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).
* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig
8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.
Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
If the bandwidth allocation fails, the error must be returned in
*channel regardless of whether the channel allocation succeeded.
Checking for c >= 0 is not correct if no channel allocation was
requested, in which case this part of the code is reached with
c == -EINVAL.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This fixes a regression due to post 2.6.30 commit "firewire: core: do
not DMA-map stack addresses" 6fdc037094.
As David Moore noted, a previously correct sizeof() expression became
wrong since the commit changed its argument from an array to a pointer.
This resulted in an oops in ohci_cancel_packet in the shared workqueue
thread's context when an isochronous resource was to be freed.
Reported-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The DMA mapping API cannot map on-stack addresses, as explained in
Documentation/DMA-mapping.txt. Convert the two cases of on-stack packet
payload buffers in firewire-core (payload of lock requests in the bus
manager work and in iso resource management) to slab-allocated memory.
There are a number on-stack buffers for quadlet write or quadlet read
requests in firewire-core and firewire-sbp2. These are harmless; they
are copied to/ from card driver internal DMA buffers since quadlet
payloads are inlined with packet headers.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Implement IPv4 over IEEE 1394 as per RFC 2734 for the newer firewire
stack. This feature has only been present in the older ieee1394 stack
via the eth1394 driver.
Still to do:
- fix ipv4_priv and ipv4_node lifetime logic
- fix determination of speeds and max payloads
- fix bus reset handling
- fix unaligned memory accesses
- fix coding style
- further testing/ improvement of fragment reassembly
- perhaps multicast support
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (rebased, copyright note, changelog)
The source files of firewire-core, firewire-ohci, firewire-sbp2, i.e.
"drivers/firewire/fw-*.c"
are renamed to
"drivers/firewire/core-*.c",
"drivers/firewire/ohci.c",
"drivers/firewire/sbp2.c".
The old fw- prefix was redundant to the directory name. The new core-
prefix distinguishes the files according to which driver they belong to.
This change comes a little late, but still before further firewire
drivers are added as anticipated RSN.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Gustavo A. R. Silva
Stefan Richter
Gustavo A. R. Silva
Thomas Gleixner
Souptick Joarder
Randy Dunlap
Kees Cook
Clemens Ladisch
Linus Torvalds
Paul Gortmaker
Tejun Heo
Jay Fenlason