The function pci_msi_check_device() is called while enabling MSI
or MSI-X interrupts to make sure the PCI device can support MSI
or MSI-X capability. This patch removes the check on MSI or MSI-X
capability in the function and lets the caller do the check.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The patch caches the MSI and MSI-X capability offset in PCI device
(struct pci_dev) so that we needn't read it from the config space
upon enabling or disabling MSI or MSI-X interrupts.
[bhelgaas: moved pm_cap size change to separate patch]
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
The new function pci_enable_msi_block_auto() tries to allocate
maximum possible number of MSIs up to the number the device
supports. It generalizes a pattern when pci_enable_msi_block()
is contiguously called until it succeeds or fails.
Opposite to pci_enable_msi_block() which takes the number of
MSIs to allocate as a input parameter,
pci_enable_msi_block_auto() could be used by device drivers to
obtain the number of assigned MSIs and the number of MSIs the
device supports.
Signed-off-by: Alexander Gordeev <agordeev@redhat.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Matthew Wilcox <willy@linux.intel.com>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/c3de2419df94a0f95ca1a6f755afc421486455e6.1353324359.git.agordeev@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Support PCI adapter interrupts using the Single-IRQ-mode. Single-IRQ-mode
disables an adapter IRQ automatically after delivering it until the SIC
instruction enables it again. This is used to reduce the number of IRQs
for streaming workloads.
Up to 64 MSI handlers can be registered per PCI function.
A hash table is used to map interrupt numbers to MSI descriptors.
The interrupt vector is scanned using the flogr instruction.
Only MSI/MSI-X interrupts are supported, no legacy INTs.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
The MSI restore function will become a function pointer in an
x86_msi_ops struct. It defaults to the implementation in the
io_apic.c and msi.c. We piggyback on the indirection mechanism
introduced by "x86: Introduce x86_msi_ops".
Cc: x86@kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: linux-pci@vger.kernel.org
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This warning was recently reported to me:
------------[ cut here ]------------
WARNING: at lib/kobject.c:595 kobject_put+0x50/0x60()
Hardware name: VMware Virtual Platform
kobject: '(null)' (ffff880027b0df40): is not initialized, yet kobject_put() is
being called.
Modules linked in: vmxnet3(+) vmw_balloon i2c_piix4 i2c_core shpchp raid10
vmw_pvscsi
Pid: 630, comm: modprobe Tainted: G W 3.1.6-1.fc16.x86_64 #1
Call Trace:
[<ffffffff8106b73f>] warn_slowpath_common+0x7f/0xc0
[<ffffffff8106b836>] warn_slowpath_fmt+0x46/0x50
[<ffffffff810da293>] ? free_desc+0x63/0x70
[<ffffffff812a9aa0>] kobject_put+0x50/0x60
[<ffffffff812e4c25>] free_msi_irqs+0xd5/0x120
[<ffffffff812e524c>] pci_enable_msi_block+0x24c/0x2c0
[<ffffffffa017c273>] vmxnet3_alloc_intr_resources+0x173/0x240 [vmxnet3]
[<ffffffffa0182e94>] vmxnet3_probe_device+0x615/0x834 [vmxnet3]
[<ffffffff812d141c>] local_pci_probe+0x5c/0xd0
[<ffffffff812d2cb9>] pci_device_probe+0x109/0x130
[<ffffffff8138ba2c>] driver_probe_device+0x9c/0x2b0
[<ffffffff8138bceb>] __driver_attach+0xab/0xb0
[<ffffffff8138bc40>] ? driver_probe_device+0x2b0/0x2b0
[<ffffffff8138bc40>] ? driver_probe_device+0x2b0/0x2b0
[<ffffffff8138a8ac>] bus_for_each_dev+0x5c/0x90
[<ffffffff8138b63e>] driver_attach+0x1e/0x20
[<ffffffff8138b240>] bus_add_driver+0x1b0/0x2a0
[<ffffffffa0188000>] ? 0xffffffffa0187fff
[<ffffffff8138c246>] driver_register+0x76/0x140
[<ffffffff815ca414>] ? printk+0x51/0x53
[<ffffffffa0188000>] ? 0xffffffffa0187fff
[<ffffffff812d2996>] __pci_register_driver+0x56/0xd0
[<ffffffffa018803a>] vmxnet3_init_module+0x3a/0x3c [vmxnet3]
[<ffffffff81002042>] do_one_initcall+0x42/0x180
[<ffffffff810aad71>] sys_init_module+0x91/0x200
[<ffffffff815dccc2>] system_call_fastpath+0x16/0x1b
---[ end trace 44593438a59a9558 ]---
Using INTx interrupt, #Rx queues: 1.
It occurs when populate_msi_sysfs fails, which in turn causes free_msi_irqs to
be called. Because populate_msi_sysfs fails, we never registered any of the
msi irq sysfs objects, but free_msi_irqs still calls kobject_del and kobject_put
on each of them, which gets flagged in the above stack trace.
The fix is pretty straightforward. We can key of the parent pointer in the
kobject. It is only set if the kobject_init_and_add succededs in
populate_msi_sysfs. If anything fails there, each kobject has its parent reset
to NULL
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Bjorn Helgaas <bhelgaas@google.com>
CC: Greg Kroah-Hartman <gregkh@suse.de>
CC: linux-pci@vger.kernel.org
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
I traced a nasty kexec on panic boot failure to the fact that we had
screaming msi interrupts and we were not disabling the msi messages at
kernel startup. The booting kernel had not enabled those interupts so
was not prepared to handle them.
I can see no reason why we would ever want to leave the msi interrupts
enabled at boot if something else has enabled those interrupts. The pci
spec specifies that msi interrupts should be off by default. Drivers
are expected to enable the msi interrupts if they want to use them. Our
interrupt handling code reprograms the interrupt handlers at boot and
will not be be able to do anything useful with an unexpected interrupt.
This patch applies cleanly all of the way back to 2.6.32 where I noticed
the problem.
Cc: stable@kernel.org
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This patch adds a per-pci-device subdirectory in sysfs called:
/sys/bus/pci/devices/<device>/msi_irqs
This sub-directory exports the set of msi vectors allocated by a given
pci device, by creating a numbered sub-directory for each vector beneath
msi_irqs. For each vector various attributes can be exported.
Currently the only attribute is called mode, which tracks the
operational mode of that vector (msi vs. msix)
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
They were implicitly getting it from device.h --> module.h but
we want to clean that up. So add the minimal header for these
macros.
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Then we can use it instead of magic number 1.
Reviewed-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Introduce an override for the arch_[teardown|setup]_msi_irqs
that can be utilized to fallback to the default arch_* code.
If a platform wants to utilize the code paths defined
in driver/pci/msi.c it has to define HAVE_DEFAULT_MSI_TEARDOWN_IRQS
or HAVE_DEFAULT_MSI_SETUP_IRQS. Otherwise the old mechanism
of over-ridding the arch_* works fine.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: x86@kernel.org
Handing down irq_desc to msi just so that msi can access
irq_desc.irq_data.msi_desc is a pretty stupid idea. The calling code
can hand down a pointer to msi_desc so msi code does not need to know
about the irq descriptor at all.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Russell King <linux@arm.linux.org.uk>
commit 2ca1af9aa3285c6a5f103ed31ad09f7399fc65d7 "PCI: MSI: Remove
unsafe and unnecessary hardware access" changed read_msi_msg_desc() to
return the last MSI message written instead of reading it from the
device, since it may be called while the device is in a reduced
power state.
However, the pSeries platform code really does need to read messages
from the device, since they are initially written by firmware.
Therefore:
- Restore the previous behaviour of read_msi_msg_desc()
- Add new functions get_cached_msi_msg{,_desc}() which return the
last MSI message written
- Use the new functions where appropriate
Acked-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
During suspend on an SMP system, {read,write}_msi_msg_desc() may be
called to mask and unmask interrupts on a device that is already in a
reduced power state. At this point memory-mapped registers including
MSI-X tables are not accessible, and config space may not be fully
functional either.
While a device is in a reduced power state its interrupts are
effectively masked and its MSI(-X) state will be restored when it is
brought back to D0. Therefore these functions can simply read and
write msi_desc::msg for devices not in D0.
Further, read_msi_msg_desc() should only ever be used to update a
previously written message, so it can always read msi_desc::msg
and never needs to touch the hardware.
Tested-by: "Michael Chan" <mchan@broadcom.com>
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Use resource_size_t for MMIO address instead of unsigned long. Otherwise,
higher 32-bits of MMIO address are cleared unexpectedly in x86-32 PAE.
Acked-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
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>
Cleanup based on the prototype from Matthew Milcox.
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cleanup based on the prototype from Matthew Milcox.
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Cleanup based on the prototype from Matthew Milcox.
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Move it from the middle of the function to the end.
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Unify msi_free_irqs() and msix_free_all_irqs(), and rename it to a
common void function free_msi_irqs().
And relocate the common function to where the prototype is located now.
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The msi_list never have MSI-X's msi_desc while MSI is enabled,
and also it never have MSI's msi_desc while MSI-X is enabled.
This patch remove check for MSI-X entry from the pci_disable_msi(),
referring that pci_disable_msix() does not have any check for MSI
entry.
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
There are 2 problems on mask states in suspend/resume.
[1]:
It is better to restore the mask states of MSI/MSI-X to initial states
(MSI is unmasked, MSI-X is masked) when we release the device.
The pci_msi_shutdown() does the restoration of mask states for MSI,
while the msi_free_irqs() does it for MSI-X. In other words, in the
"disable" path both of MSI and MSI-X are handled, but in the "shutdown"
path only MSI is handled.
MSI:
pci_disable_msi()
=> pci_msi_shutdown()
[ mask states for MSI restored ]
=> msi_set_enable(dev, pos, 0);
=> msi_free_irqs()
MSI-X:
pci_disable_msix()
=> pci_msix_shutdown()
=> msix_set_enable(dev, 0);
=> msix_free_all_irqs
=> msi_free_irqs()
[ mask states for MSI-X restored ]
This patch moves the masking for MSI-X from msi_free_irqs() to
pci_msix_shutdown().
This change has some positive side effects:
- It prevents OS from touching mask states before reading preserved
bits in the register, which can be happen if msi_free_irqs() is
called from error path in msix_capability_init().
- It also prevents touching the register after turning off MSI-X in
"disable" path, which can be a problem on some devices.
[2]:
We have cache of the mask state in msi_desc, which is automatically
updated when msi/msix_mask_irq() is called. This cached states are
used for the resume.
But since what need to be restored in the resume is the states before
the shutdown on the suspend, calling msi/msix_mask_irq() from
pci_msi/msix_shutdown() is not appropriate.
This patch introduces __msi/msix_mask_irq() that do mask as same
as msi/msix_mask_irq() but does not update cached state, for use
in pci_msi/msix_shutdown().
[updated: get rid of msi/msix_mask_irq_nocache() (proposed by Matthew Wilcox)]
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The initial state of mask register of MSI is unmasked. We set it
masked before calling arch_setup_msi_irqs(). If arch_setup_msi_irq()
fails, it is better to restore the state of the mask register.
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
These names are too long! Drop _OFFSET to save some bytes/lines.
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
In current code it continues setup even if alloc_msi_entry() for MSI-X
is failed due to lack of memory. It means arch_setup_msi_irqs() might
be called with msi_desc entries less than its argument nvec.
At least x86's arch_setup_msi_irqs() uses list_for_each_entry() for
dev->msi_list that suspected to have entries same numbers as nvec, and
it doesn't check the number of allocated vectors and passed arg nvec.
Therefore it will result in success of pci_enable_msix(), with less
vectors allocated than requested.
This patch fixes the error route to return -ENOMEM, instead of continuing
the setup (proposed by Matthew Wilcox).
Note that there is no iounmap in msi_free_irqs() if no msi_disc is
allocated.
Reviewed-by: Matthew Wilcox <matthew@wil.cx>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Use msix_mask_irq() instead of direct use of writel, so as not to clear
preserved bits in the Vector Control register [31:1].
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The previous MSI-X fix (8d18101853) had
three bugs. First, it didn't move the write that disabled the vector.
This led to writing garbage to the MSI-X vector (spotted by Michael
Ellerman). It didn't fix the PCI resume case, and it had a race window
where the device could generate an interrupt before the MSI-X registers
were programmed (leading to a DMA to random addresses).
Fortunately, the MSI-X capability has a bit to mask all the vectors.
By setting this bit instead of clearing the enable bit, we can ensure
the device will not generate spurious interrupts. Since the capability
is now enabled, the NIU device will not have a problem with the reads
and writes to the MSI-X registers being in the original order in the code.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Reviewed-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
We have the 'pos' of the MSI capability at all locations which call
msi_set_enable(), so pass it to msi_set_enable() instead of making it
find the capability every time.
Reviewed-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
pci_enable_msix currently returns -EINVAL if you ask
for more vectors than supported by the device, which would
typically cause fallback to regular interrupts.
It's better to return the table size, making the driver retry
MSI-X with less vectors.
Reviewed-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The NIU device refuses to allow accesses to MSI-X registers before MSI-X
is enabled. This patch fixes the problem by moving the read of the mask
register to after MSI-X is enabled.
Reported-by: David S. Miller <davem@davemloft.net>
Tested-by: David S. Miller <davem@davemloft.net>
Reviewed-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Add the new API pci_enable_msi_block() to allow drivers to
request multiple MSI and reimplement pci_enable_msi in terms of
pci_enable_msi_block. Ensure that the architecture back ends don't
have to know about multiple MSI.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Since most of the callers already know whether they have an MSI or
an MSI-X capability, split msi_set_mask_bits() into msi_mask_irq()
and msix_mask_irq(). The only callers which don't (mask_msi_irq()
and unmask_msi_irq()) can share code in msi_set_mask_bit(). This then
becomes the only caller of msix_flush_writes(), so we can inline it.
The flushing read can be to any address that belongs to the device,
so we can eliminate the calculation too.
We can also get rid of maskbits_mask from struct msi_desc and simply
recalculate it on the rare occasion that we need it. The single-bit
'masked' element is replaced by a copy of the 32-bit 'masked' register,
so this patch does not affect the size of msi_desc.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
MSI interrupts have a mask_pos where MSI-X have a mask_base. Use a
transparent union to get rid of some ugly casts.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
By passing the pci_dev into alloc_msi_entry() we can be sure that
the ->dev entry is always assigned and so we don't need to check it.
Also, we used kzalloc() so we don't need to initialise ->irq to 0.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
By changing from a 5-bit field to a 1-bit field, we free up some bits
that can be used by a later patch. Also rearrange the fields for better
packing on 64-bit platforms (reducing the size of msi_desc from 72 bytes
to 64 bytes).
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
There is code in msix_capability_init() which, when the requested number
of MSI-X couldn't be allocated, calculates how many MSI-X /could/ be
allocated and returns that to the driver. That allows the driver to then
make a second request, with a number of MSIs that should succeed.
The current code requires the arch code to setup as many msi_descs as it
can, and then return to the generic code. On some platforms the arch
code may already know how many MSI-X it can allocate, before it sets up
any of the msi_descs.
So change the logic such that if the arch code returns a positive error
code, that is taken to be the number of MSI-X that could be allocated.
If the error code is negative we still calculate the number available
using the old method.
Because it's a little subtle, make sure the error return code from
arch_setup_msi_irq() is always negative. That way only implementations
of arch_setup_msi_irqs() need to be careful about returning a positive
error code.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Weak functions aren't all they're cracked up to be. They lead to
incorrect binaries with some toolchains, they require us to have empty
functions we otherwise wouldn't, and the unused code is not elided
(as of gcc 4.3.2 anyway).
So replace the weak MSI arch hooks with the #define foo foo idiom. We no
longer need empty versions of arch_setup/teardown_msi_irq().
This is less source (by 1 line!), and results in smaller binaries too:
text data bss dec hex filename
9354300 1693916 678424 11726640 b2ef30 build/powerpc/vmlinux-before
9354052 1693852 678424 11726328 b2edf8 build/powerpc/vmlinux-after
Also smaller on x86_64 and arm (iop13xx).
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Introduce new function pci_msix_table_size() returning the size of
the MSI-X table of given PCI device or 0 if the device doesn't
support MSI-X.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Reviewed-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Hidetoshi Seto points out that commit
bffac3c593 has wrong values in the array.
Rather than correct the array, we can just use a bounds check and
perform the calculation specified in the comment. As a bonus, this will
not run off the end of the array if the device specifies an illegal
value in the MSI capability.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Add an msi_mask() function which returns the correct bitmask for the
number of MSI interrupts you have. This fixes an undefined bug in
msi_capability_init().
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The _OSC capability OSC_MSI_SUPPORT is set when the root bridge is added
with pci_acpi_osc_support(), so we no longer need to do it in the PCI
MSI driver. Also adds the function pci_msi_enabled, which returns true
if pci=nomsi is not on the kernel command-line.
Signed-off-by: Andrew Patterson <andrew.patterson@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Impact: simplify code
Pass irq_desc and cfg around, instead of raw IRQ numbers - this way
we dont have to look it up again and again.
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Currently linux doesn't have any code to set the "MSI supported" bit in
Support Fireld of _OSC. This patch adds the code for that.
Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
In msi_capability_init, we can make use of the calculated results
instead of calling is_mask_bit_support and is_64bit_address twice.
Signed-off-by: Jike Song <albcamus@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
With the recent change to avoid masking MSIs using the MSI enable bit, devices
without an MSI mask bit will have their MSI capability always enabled when MSI
is in use, so we need to restore it regardless of the mask bit state.
Fixes kernel bz 11178.
Acked-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
David Vrabel has a device which generates an interrupt storm on the INTx
pin if we disable MSI interrupts altogether. Masking interrupts is only
a performance optimisation, so we can ignore the request to mask the
interrupt.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Convert printks to use dev_printk().
I converted pr_debug() to dev_dbg(). Both use KERN_DEBUG and are enabled
only when DEBUG is defined.
I converted printk(KERN_DEBUG) to dev_printk(KERN_DEBUG), not to dev_dbg(),
because dev_dbg() is only enabled when DEBUG is defined.
I converted DBG(KERN_INFO) (only in setup-bus.c) to dev_info(). The DBG()
name makes it sound like debug, but it's been enabled forever, so dev_info()
preserves the previous behavior.
I tried to make the resource assignment formats more consistent, e.g.,
"BAR %d: got res [%#llx-%#llx] bus [%#llx-%#llx] flags %#lx\n"
instead of sometimes using "start-end" and sometimes using "size@start".
I'm not attached to one or the other; I'd just like them consistent.
Signed-off-by: Bjorn Helgaas <bjorn.helgaas@hp.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The position of MSI capability is already cached in the msi_desc when
we enter the msi_set_mask_bits(). Use it instead.
Signed-off-by: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
[PATCH 2/2] pci/irq: let pci_device_shutdown to call pci_msi_shutdown v2
this change
| commit 23a274c8a5
| Author: Prakash, Sathya <sathya.prakash@lsi.com>
| Date: Fri Mar 7 15:53:21 2008 +0530
|
| [SCSI] mpt fusion: Enable MSI by default for SAS controllers
|
| This patch modifies the driver to enable MSI by default for all SAS chips.
|
| Signed-off-by: Sathya Prakash <sathya.prakash@lsi.com>
| Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
|
Causes the kexec of a RHEL 5.1 kernel to fail.
root casue: the rhel 5.1 kernel still uses INTx emulation. and
mptscsih_shutdown doesn't call pci_disable_msi to reenable INTx on kexec path
So call pci_msi_shutdown in the shutdown path to do the same thing to msix
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@hobbes.lan>
[PATCH 1/2] pci/irq: restore mask_bits in msi shutdown -v3
Yinghai found that kexec'ing a RHEL 5.1 kernel with 2.6.25-rc3+ kernels
prevents his NIC from working. He bisected to
| commit 89d694b9db
| Author: Thomas Gleixner <tglx@linutronix.de>
| Date: Mon Feb 18 18:25:17 2008 +0100
|
| genirq: do not leave interupts enabled on free_irq
|
| The default_disable() function was changed in commit:
|
| 76d2160147
| genirq: do not mask interrupts by default
|
For MSI, default_shutdown will call mask_bit for msi device. All mask bits
will left disabled after free_irq. Then in the kexec case, the next kernel
can only use msi_enable bit, so all device's MSI can not be used.
So lets to restore the mask bit to its pci reset defined value (enabled) when
we disable the kernels use of msi to be a little friendlier to kexec'd kernels.
Extend msi_set_mask_bit to msi_set_mask_bits to take mask, so we can fully
restore that to 0x00 instead of 0xfe.
Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Jesse Barnes <jbarnes@hobbes.lan>
This patch fixes the following problem present with older gcc versions:
<-- snip -->
...
CC drivers/pci/msi.o
/home/bunk/linux/kernel-2.6/git/linux-2.6/drivers/pci/msi.c:692: warning: weak declaration of `arch_msi_check_device' after first use results in unspecified behavior
/home/bunk/linux/kernel-2.6/git/linux-2.6/drivers/pci/msi.c:704: warning: weak declaration of `arch_setup_msi_irqs' after first use results in unspecified behavior
/home/bunk/linux/kernel-2.6/git/linux-2.6/drivers/pci/msi.c:724: warning: weak declaration of `arch_teardown_msi_irqs' after first use results in unspecified behavior
...
<-- snip -->
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
PCI error recovery usually involves the PCI adapter being reset.
If the device is using MSI, the reset will cause the MSI state
to be lost; the device driver needs to restore the MSI state.
The pci_restore_msi_state() routine is currently protected
by CONFIG_PM; remove this, and also export the symbol, so
that it can be used in a modle.
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
A reasonably common problem with some devices is that they will
disable MSI generation when the INTX_DISABLE bit is set in the
PCI_COMMAND register.
Quirk this explicitly, guarding the pci_intx() calls in msi.c with
this quirk indication.
The first entries for this quirk are for 5714 and 5780 Tigon3 chips,
and thus we can remove the workaround code from the tg3.c driver.
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Michael Chan <mchan@broadcom.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
While reading the MSI code trying to find a reason why MSI wouldn't
work for devices that have a 32-bit MSI address capability, I noticed
that read_msi_msg() seems to read the message data from the wrong
offset in this case.
Signed-off-by: Roland Dreier <roland@digitalvampire.org>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
"Mike Miller (OS Dev)" <mikem@beardog.cca.cpqcorp.net> writes:
Found what seems the problem with our vectors being listed backward. In
drivers/pci/msi.c we should be using list_add_tail rather than list_add to
preserve the ordering across various kernels. Please consider this for
inclusion.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Screwed-up-by: Michael Ellerman <michael@ellerman.id.au>
Cc: "Mike Miller (OS Dev)" <mikem@beardog.cca.cpqcorp.net>
Cc: Andi Kleen <ak@suse.de>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In file included from drivers/pci/msi.c:22:
include/asm/smp.h:17:26: asm/arch/smp.h: No such file or directory
include/asm/smp.h:20:3: #error "<asm-arm/smp.h> included in non-SMP build"
include/asm/smp.h:23:1: warning: "raw_smp_processor_id" redefined
In file included from include/linux/sched.h:65,
from include/linux/mm.h:4,
from drivers/pci/msi.c:10:
include/linux/smp.h:85:1: warning: this is the location of the previous
definition
Tested on powerpc, i386, and x86_64.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Today's find is a triggered assertion in msi_free_irqs() when the system
doesn't support MSI, in which case arch_setup_msi_irqs() always returns
an error.
The problem is that when this happens we branch into msi_free_irqs(), to
which you added the following assertion loop:
list_for_each_entry(entry, &dev->msi_list, list)
BUG_ON(irq_has_action(entry->irq));
Well, if arch_setup_msi_irqs() fails, entry->irq will be zero and
although that's never assigned to any normal devices we use that IRQ
number for the timer interrupt on sparc64 so this assertion triggers.
Better to test for zero before doing the irq_has_action() assertion
thing.
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.
Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This patch introduces an optional function, arch_teardown_msi_irqs(),
which gives an arch the opportunity to do per-device teardown for
MSI/X. If that's not required, the default version simply calls
arch_teardown_msi_irq() for each msi irq required.
arch_teardown_msi_irqs() is simply passed a pdev, attached to the pdev
is a list of msi_descs, it is up to the arch to free the irq associated
with each of these as appropriate.
For archs that _don't_ implement arch_teardown_msi_irqs(), all msi_descs
with irq == 0 are considered unallocated, and the arch teardown routine
is not called on them.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch introduces an optional function, arch_setup_msi_irqs(),
(note the plural) which gives an arch the opportunity to do per-device
setup for MSI/X and then allocate all the requested MSI/Xs at once.
If that's not required by the arch, the default version simply calls
arch_setup_msi_irq() for each MSI irq required.
arch_setup_msi_irqs() is passed a pdev, attached to the pdev is a list
of msi_descs with irq == 0, it is up to the arch to connect these up to
an irq (via set_irq_msi()) or return an error. For convenience the number
of vectors and the type are passed also.
All msi_descs with irq != 0 are considered allocated, and the arch
teardown routine will be called on them when necessary.
The existing semantics of pci_enable_msix() are that if the requested
number of irqs can not be allocated, the maximum number that _could_ be
allocated is returned. To support that, we define that in case of an
error from arch_setup_msi_irqs(), the number of msi_descs with irq != 0
are considered allocated, and are counted toward the "max that could be
allocated".
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
set_irq_msi() currently connects an irq_desc to an msi_desc. The archs call
it at some point in their setup routine, and then the generic code sets up the
reverse mapping from the msi_desc back to the irq.
set_irq_msi() should do both connections, making it the one and only call
required to connect an irq with it's MSI desc and vice versa.
The arch code MUST call set_irq_msi(), and it must do so only once it's sure
it's not going to fail the irq allocation.
Given that there's no need for the arch to return the irq anymore, the return
value from the arch setup routine just becomes 0 for success and anything else
for failure.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Now that we keep a list of msi descriptors, we don't need first_msi_irq
in the pci dev.
If we somehow have zero MSIs configured list_entry() will give us weird
oopes or nice memory corruption bugs. So be paranoid. Add BUG_ONs and also
a check in pci_msi_check_device() to make sure nvec > 0.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The msi descriptors are linked together with what looks a lot like
a linked list, but isn't a struct list_head list. Make it one.
The only complication is that previously we walked a list of irqs, and
got the descriptor for each with get_irq_msi(). Now we have a list of
descriptors and need to get the irq out of it, so it needs to be in the
actual struct msi_desc. We use 0 to indicate no irq is setup.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Add an arch_check_device(), which gives archs a chance to check the input
to pci_enable_msi/x. The arch might be interested in the value of nvec so
pass it in. Propagate the error value returned from the arch routine out
to the caller.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
As pointed out by Eric, the name pci_msi_supported() suggests it should
return a boolean value, however it doesn't. So update the name to be
a bit less confusing and update the doco too.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Consolidate precondition checks into a single if statement.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
pci_enable_msi() and pci_enable_msix() both search for the MSI/MSI-X
capability, we can fold this into pci_msi_supported() by passing the
type in.
Update the code to match the comment for pci_msi_supported(). That is
it returns 0 on success, and anything else indicates an error.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We don't need a special cache just for msi descriptors. They're not
particularly large, under 100 bytes for sure, and don't seem to require any
special alignment etc. On most systems there will be relatively few MSIs,
and hence we waste most of a page on the cache. Better to just kzalloc the
space for the few we do need.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Move EXPORT_SYMBOL()s near their definition.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
When freeing MSIs and MSI-Xs, we BUG_ON() if the irq has not been
freed, ie. if it still has an action. We can consolidate all of these
BUG_ON()s into msi_free_irqs() as all the code paths lead there almost
immediately anyway.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
For the MSI-X case we do exactly the same logic in pci_disable_msix() and
msi_remove_pci_irq_vectors(), so consolidate them.
msi_remove_pci_irq_vectors() wasn't setting dev->first_msi_irq to 0, but
I think it should have been, so the consolidated version does.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Although it might be nice to do a printk before BUG'ing, it's really not
necessary, and it complicates the code.
The behaviour has changed slightly, in that before we set a flag if the irq
had an action, and continued freeing the other irqs. But as I see it that's
all irrelevant because we end up BUG'ing anyway.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Although it might be nice to do a printk before BUG'ing, it's really not
necessary, and it complicates the code.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Although it might be nice to do a printk before BUG'ing, it's really not
necessary, and it complicates the code.
The behaviour has changed slightly, in that before we set a flag if the irq
had an action, and continued freeing the other irqs. But as I see it that's
all irrelevant because we end up BUG'ing anyway.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Although it might be nice to do a printk before BUG'ing, it's really not
necessary, and it complicates the code.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This patch fixes a kernel bug which is triggered when using the
irqbalance daemon with MSI-X hardware.
Because both MSI-X interrupt messages and MSI-X table writes are posted,
it's possible for them to cross while in-flight. This results in
interrupts being received long after the kernel thinks they're disabled,
and in interrupts being sent to stale vectors after rebalancing.
This patch performs a read flush after writes to the MSI-X table for
mask and unmask operations. Since the SMP affinity is set while
the interrupt is masked, and since it's unmasked immediately after,
no additional flushes are required in the various affinity setting
routines.
This patch has been validated with (unreleased) network hardware which
uses MSI-X.
Revised with input from Eric Biederman.
Signed-off-by: Mitch Williams <mitch.a.williams@intel.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This is a simplified and actually more comprehensive form of a bug
fix from Mitch Williams <mitch.a.williams@intel.com>.
When we mask or unmask a msi-x irqs the writes may be posted because
we are writing to memory mapped region. This means the mask and
unmask don't happen immediately but at some unspecified time in the
future. Which is out of sync with how the mask/unmask logic work
for ioapic irqs.
The practical result is that we get very subtle and hard to track down
irq migration bugs.
This patch performs a read flush after writes to the MSI-X table for mask
and unmask operations. Since the SMP affinity is set while the interrupt
is masked, and since it's unmasked immediately after, no additional flushes
are required in the various affinity setting routines.
The testing by Mitch Williams on his especially problematic system should
still be valid as I have only simplified the code, not changed the
functionality.
We currently have 7 drivers: cciss, mthca, cxgb3, forceth, s2io,
pcie/portdrv_core, and qla2xxx in 2.6.21 that are affected by this
problem when the hardware they driver is plugged into the right slot.
Given the difficulty of reproducing this bug and tracing it down to
anything that even remotely resembles a cause, even if people are
being affected we aren't likely to see many meaningful bug reports, and
the people who see this bug aren't likely to be able to reproduce this
bug in a timely fashion. So it is best to get this problem fixed
as soon as we can so people don't have problems.
Then if people do have a kernel message stating "No irq for vector" we
will know it is yet another novel cause that needs a complete new
investigation.
Cc: Greg KH <greg@kroah.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Mitch Williams <mitch.a.williams@intel.com>
Acked-by: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There are two ways pci_save_state and pci_restore_state are used. As
helper functions during suspend/resume, and as helper functions around
a hardware reset event. When used as helper functions around a hardware
reset event there is no reason to believe the calls will be paired, nor
is there a good reason to believe that if we restore the msi state from
before the reset that it will match the current msi state. Since arch
code may change the msi message without going through the driver, drivers
currently do not have enough information to even know when to call
pci_save_state to ensure they will have msi state in sync with the other
kernel irq reception data structures.
It turns out the solution is straight forward, cache the state in the
existing msi data structures (not the magic pci saved things) and
have the msi code update the cached state each time we write to the hardware.
This means we never need to read the hardware to figure out what the hardware
state should be.
By modifying the caching in this manner we get to remove our save_state
routines and only need to provide restore_state routines.
The only fields that were at all tricky to regenerate were the msi and msi-x
control registers and the way we regenerate them currently is a bit dependent
upon assumptions on how we use the allow msi registers to be configured and used
making the code a little bit brittle. If we ever change what cases we allow
or how we configure the msi bits we can address the fragility then.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Auke Kok <auke-jan.h.kok@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For devices that do not support msi-x we only support 1 interrupt. Therefore
we can disable that one interrupt by disabling the msi capability itself. If
we leave the intx interrupts disabled while we have the msi capability
disabled no interrupts should be delivered from that device.
Devices with just the minimal msi support (and thus hitting this code path)
include things like the intel e1000 nic, so it looks like is going to be a
fairly common case and thus important to get right.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
enable/disable_msi_mode have several side effects which keeps them from being
generally useful. So this patch replaces them with with two much more
targeted functions: msi_set_enable and msix_set_enable.
This patch makes pci_dev->msi_enabled and pci_dev->msix_enabled the definitive
way to test if linux has enabled the msi capability, and has the appropriate
msi data structures set up.
This patch ensures that while writing the msi messages in save/restore and
during device initialization we have the msi capability disabled so we don't
get into races. The pci spec requires that we do not have the msi capability
enabled and the msi messages unmasked while we write the messages. Completely
disabling the capability is overkill but it is easy :)
Care has been taken so we never have both a msi capability and intx enabled
simultaneously. We haven't run into a problem yet but better safe then sorry.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In some cases when we are not using msi we need a way to ensure that the
hardware does not have an msi capability enabled. Currently the code has been
calling disable_msi_mode to try and achieve that. However disable_msi_mode
has several other side effects and is only available when msi support is
compiled in so it isn't really appropriate.
Instead this patch implements pci_msi_off which disables all msi and msix
capabilities unconditionally with no additional side effects.
pci_disable_device was redundantly clearing the bus master enable flag and
clearing the msi enable bit. A device that is not allowed to perform bus
mastering operations cannot generate intx or msi interrupt messages as those
are essentially a special case of dma, and require bus mastering. So the call
in pci_disable_device to disable msi capabilities was redundant.
quirk_pcie_pxh also called disable_msi_mode and is updated to use pci_msi_off.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The arch hooks arch_setup_msi_irq and arch_teardown_msi_irq are now
responsible for allocating and freeing the linux irq in addition to
setting up the the linux irq to work with the interrupt.
arch_setup_msi_irq now takes a pci_device and a msi_desc and returns
an irq.
With this change in place this code should be useable by all platforms
except those that won't let the OS touch the hardware like ppc RTAS.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
We need to be able to get from an irq number to a struct msi_desc.
The msi_desc array in msi.c had several short comings the big one was
that it could not be used outside of msi.c. Using irq_data in struct
irq_desc almost worked except on some architectures irq_data needs to
be used for something else.
So this patch adds a msi_desc pointer to irq_desc, adds the appropriate
wrappers and changes all of the msi code to use them.
The dynamic_irq_init/cleanup code was tweaked to ensure the new
field is left in a well defined state.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The attach_msi_entry has been reduced to a single simple assignment,
so for simplicity remove the abstraction and directory perform the
assignment.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Since msi_remove_pci_irq_vectors is designed to be called during
hotplug remove it is actively wrong to query the hardware and expect
meaningful results back.
To that end remove the pci_find_capability calls. Testing
dev->msi_enabled and dev->msix_enabled gives us all of the information
we need.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
With the removal of msi_lookup_irq all of the functions using msi_lock
operated on a single device and none of them could reasonably be
called on that device at the same time.
Since what little synchronization that needs to happen needs to happen
outside of the msi functions, msi_lock could never be contended and as
such is useless and just complicates the code.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The function msi_lookup_irq was horrible. As a side effect of running
it changed dev->irq, and then the callers would need to change it
back. In addition it does a global scan through all of the irqs,
which seems to be the sole justification of the msi_lock.
To remove the neede for msi_lookup_irq I added first_msi_irq to struct
pci_dev. Then depending on the context I replaced msi_lookup_irq with
dev->first_msi_irq, dev->msi_enabled, or dev->msix_enabled.
msi_enabled and msix_enabled were already present in pci_dev for other
reasons.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The PCI save/restore code doesn't need to care about MSI vs MSI-X, all
it really wants is to say "save/restore all MSI(-X) info for this device".
This is borne out in the code, we call the MSI and MSI-X save routines
side by side, and similarly with the restore routines.
So combine the MSI/MSI-X routines into pci_save_msi_state() and
pci_restore_msi_state(). It is up to those routines to decide what state
needs to be saved.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
pci_scan_msi_device() doesn't do anything anymore, so remove it.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
I don't see any reason why we need pci_msi_quirk, quirk code can just
call pci_no_msi() instead.
Remove the check of pci_msi_quirk in msi_init(). This is safe as all
calls to msi_init() are protected by calls to pci_msi_supported(),
which checks pci_msi_enable, which is disabled by pci_no_msi().
The pci_disable_msi routines didn't check pci_msi_quirk, only
pci_msi_enable, but as far as I can see that was a bug not a feature.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Gavin Shan
Bjorn Helgaas
Alexander Gordeev
Jan Glauber
Konrad Rzeszutek Wilk
Neil Horman
Eric W. Biederman
Paul Gortmaker
Thomas Gleixner
Sheng Yang
Ben Hutchings
Kenji Kaneshige
Tejun Heo
Hidetoshi Seto
Matthew Wilcox
Matthew Wilcox
Michael S. Tsirkin
Michael Ellerman
Rafael J. Wysocki
Matthew Wilcox
Andrew Patterson
Yinghai Lu
Taku Izumi
Jike Song
Jesse Barnes
Bjorn Helgaas
Yinghai Lu
Adrian Bunk
Linas Vepstas
David Miller
Roland Dreier
Dan Williams
Randy Dunlap
Mitch Williams