15 Oct, 2011
1 commit
-
The land of PCI power management is a land of sorrow and ugliness,
especially in the area of signaling events by devices. There are
devices that set their PME Status bits, but don't really bother
to send a PME message or assert PME#. There are hardware vendors
who don't connect PME# lines to the system core logic (they know
who they are). There are PCI Express Root Ports that don't bother
to trigger interrupts when they receive PME messages from the devices
below. There are ACPI BIOSes that forget to provide _PRW methods for
devices capable of signaling wakeup. Finally, there are BIOSes that
do provide _PRW methods for such devices, but then don't bother to
call Notify() for those devices from the corresponding _Lxx/_Exx
GPE-handling methods. In all of these cases the kernel doesn't have
a chance to receive a proper notification that it should wake up a
device, so devices stay in low-power states forever. Worse yet, in
some cases they continuously send PME Messages that are silently
ignored, because the kernel simply doesn't know that it should clear
the device's PME Status bit.This problem was first observed for "parallel" (non-Express) PCI
devices on add-on cards and Matthew Garrett addressed it by adding
code that polls PME Status bits of such devices, if they are enabled
to signal PME, to the kernel. Recently, however, it has turned out
that PCI Express devices are also affected by this issue and that it
is not limited to add-on devices, so it seems necessary to extend
the PME polling to all PCI devices, including PCI Express and planar
ones. Still, it would be wasteful to poll the PME Status bits of
devices that are known to receive proper PME notifications, so make
the kernel (1) poll the PME Status bits of all PCI and PCIe devices
enabled to signal PME and (2) disable the PME Status polling for
devices for which correct PME notifications are received.Tested-by: Sarah Sharp
Signed-off-by: Rafael J. Wysocki
Signed-off-by: Jesse Barnes
30 Jul, 2011
1 commit
-
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI: remove printks about disabled bridge windows
PCI: fold pci_calc_resource_flags() into decode_bar()
PCI: treat mem BAR type "11" (reserved) as 32-bit, not 64-bit, BAR
PCI: correct pcie_set_readrq write size
PCI: pciehp: change wait time for valid configuration access
x86/PCI: Preserve existing pci=bfsort whitelist for Dell systems
PCI: ARI is a PCIe v2 feature
x86/PCI: quirks: Use pci_dev->revision
PCI: Make the struct pci_dev * argument of pci_fixup_irqs const.
PCI hotplug: cpqphp: use pci_dev->vendor
PCI hotplug: cpqphp: use pci_dev->subsystem_{vendor|device}
x86/PCI: config space accessor functions should not ignore the segment argument
PCI: Assign values to 'pci_obff_signal_type' enumeration constants
x86/PCI: reduce severity of host bridge window conflict warnings
PCI: enumerate the PCI device only removed out PCI hieratchy of OS when re-scanning PCI
PCI: PCIe AER: add aer_recover_queue
x86/PCI: select direct access mode for mmconfig option
PCI hotplug: Rename is_ejectable which also exists in dock.c
22 Jul, 2011
1 commit
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In addition to native PCIe AER, now APEI (ACPI Platform Error
Interface) GHES (Generic Hardware Error Source) can be used to report
PCIe AER errors too. To add support to APEI GHES PCIe AER recovery,
aer_recover_queue is added to export the recovery function in native
PCIe AER driver.Recoverable PCIe AER errors are reported via NMI in APEI GHES. Then
APEI GHES uses irq_work to delay the error processing into an IRQ
handler. But PCIe AER recovery can be very time-consuming, so
aer_recover_queue, which can be used in IRQ handler, delays the real
recovery action into the process context, that is, work queue.Signed-off-by: Huang Ying
Signed-off-by: Jesse Barnes
29 Jun, 2011
1 commit
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Merriam-Webster tells us that the word exists. However ...
* Google suggests `forcibly' because it doesn't recognize `forcedly'.
* Google lists 494 thousand results for `forcedly'.
* Google lists 13.7 million results for `forcibly'.
* Linus's repo contains 1 occurrence of `forcedly' ( 0 after my change).
* Linus's repo contains 60 occurrences of `forcibly' (61 after my change).Signed-off-by: Michael Witten
Signed-off-by: Jiri Kosina
22 May, 2011
2 commits
-
In the commit 28eb5f2, aer_osc_setup is removed but corresponding
definiton information in the aerdrv.h is missed.Acked-by: Rafael J. Wysocki
Signed-off-by: Chen Gong
Signed-off-by: Jesse Barnes -
Need to use it in _e1000e_disable_aspm. This routine is used for error
recovery, where the pci_bus_sem is already held, and we don't want
pci_disable_link_state to try to take it again. So add a locked variant
for use in cases like this.Found lock up:
[ 2374.654557] kworker/32:1 D ffff881027f6b0f0 0 6075 2 0x00000000
[ 2374.654816] ffff88503f099a68 0000000000000046 ffff88503f098000 0000000000004000
[ 2374.654837] 00000000001d1ec0 ffff88503f099fd8 00000000001d1ec0 ffff88503f099fd8
[ 2374.654860] 0000000000004000 00000000001d1ec0 ffff88503dcc8000 ffff88503f090000
[ 2374.654880] Call Trace:
[ 2374.654898] [] ? __lock_acquired+0x3a/0x224
[ 2374.654914] [] ? _raw_spin_unlock_irq+0x30/0x36
[ 2374.654925] [] ? trace_hardirqs_on_caller+0x1f/0x178
[ 2374.654936] [] rwsem_down_failed_common+0xd3/0x103
[ 2374.654945] [] ? __lock_contended+0x3a/0x2a2
[ 2374.654955] [] rwsem_down_read_failed+0x12/0x14
[ 2374.654967] [] call_rwsem_down_read_failed+0x14/0x30
[ 2374.654981] [] ? pci_disable_link_state+0x5f/0xf5
[ 2374.654990] [] ? down_read+0x7e/0x91
[ 2374.654999] [] ? pci_disable_link_state+0x5f/0xf5
[ 2374.655008] [] pci_disable_link_state+0x5f/0xf5
[ 2374.655024] [] e1000e_disable_aspm+0x55/0x5a
[ 2374.655037] [] e1000_io_slot_reset+0x59/0xea
[ 2374.655048] [] ? report_mmio_enabled+0x5d/0x5d
[ 2374.655057] [] report_slot_reset+0x2e/0x5d
[ 2374.655072] [] pci_walk_bus+0x8a/0xb7
[ 2374.655081] [] ? report_mmio_enabled+0x5d/0x5d
[ 2374.655091] [] broadcast_error_message+0xa4/0xb2
[ 2374.655101] [] ? pci_bus_read_config_dword+0x72/0x80
[ 2374.655110] [] do_recovery+0x9e/0xf9
[ 2374.655120] [] handle_error_source+0x4c/0x51
[ 2374.655129] [] aer_isr_one_error+0x1e9/0x21a
[ 2374.655138] [] aer_isr+0xc7/0xcc
[ 2374.655147] [] ? aer_isr_one_error+0x21a/0x21a
[ 2374.655159] [] process_one_work+0x237/0x3ec
[ 2374.655168] [] ? process_one_work+0x1a8/0x3ec
[ 2374.655178] [] worker_thread+0x17c/0x240
[ 2374.655186] [] ? trace_hardirqs_on+0xd/0xf
[ 2374.655196] [] ? manage_workers+0xab/0xab
[ 2374.655209] [] kthread+0xa0/0xa8
[ 2374.655223] [] kernel_thread_helper+0x4/0x10
[ 2374.655232] [] ? retint_restore_args+0xe/0xe
[ 2374.655243] [] ? __init_kthread_worker+0x5b/0x5b
[ 2374.655252] [] ? gs_change+0xb/0xbwhen aer happens,
pci_walk_bus already have down_read(&pci_bus_sem)...
then report_slot_reset
==> e1000_io_slot_reset
==> e1000e_disable_aspm
==> pci_disable_link_state...We can not use pci_disable_link_state, and it will try to hold pci_bus_sem again.
Try to have __pci_disable_link_state that will not need to hold pci_bus_sem.
-v2: change name to pci_disable_link_state_locked() according to Jesse.
[jbarnes: make sure new function is exported for modules]
Signed-off-by: Yinghai Lu
Signed-off-by: Jesse Barnes
11 May, 2011
2 commits
-
If it was preempted, and the variable aer_mask_override is changed
after the spin_unlock_irqrestore it will write an uninitialized
variable by the pci_write_config_dword() function.Signed-off-by: Wanlong Gao
Signed-off-by: Jesse Barnes -
Commit 2f671e2d allowed us to clear ASPM state when the FADT
tells us it isn't supported, but we don't put this into effect
if the aspm_policy is set to POLICY_POWERSAVE. Enable the
state to be cleared regardless of policy.Signed-off-by: Alex Williamson
Signed-off-by: Jesse Barnes
26 Mar, 2011
1 commit
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* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI: Disable ASPM when _OSC control is not granted for PCIe services
PCI: Changing ASPM policy, via /sys, to POWERSAVE could cause NMIs
PCI: PCIe links may not get configured for ASPM under POWERSAVE mode
PCI/ACPI: Report ASPM support to BIOS if not disabled from command line
23 Mar, 2011
1 commit
-
Conflicts:
arch/x86/kernel/acpi/sleep.cSigned-off-by: Len Brown
22 Mar, 2011
6 commits
-
The AER error information printing support is implemented in
drivers/pci/pcie/aer/aer_print.c. So some string constants, functions
and macros definitions can be re-used without being exported.The original PCIe AER error information printing function is not
re-used directly because the overall format is quite different. And
changing the original printing format may make some original users'
scripts broken.Signed-off-by: Huang Ying
CC: Jesse Barnes
CC: Zhang Yanmin
Signed-off-by: Len Brown -
When printing PCIe AER error information, each line is prefixed with
PCIe device and driver information. In original implementation, the
prefix is generated when each line is printed. In fact, all lines
share the same prefix. So this patch pre-generated the prefix, and
use that one when each line is printed.In addition to common prefix can be pre-generated, the trailing white
spaces in string constants and NULLs in char * array constants can be
removed too. These can reduce the object file size further.The size of object file before and after changing is as follow:
text data bss dec
before: 3038 0 0 3038
after: 2118 0 0 2118Signed-off-by: Huang Ying
CC: Jesse Barnes
CC: Zhang Yanmin
Signed-off-by: Len Brown -
v3 -> v2: Added text to describe the problem
v2 -> v1: Split this patch from v1
v1 : Part of: http://marc.info/?l=linux-pci&m=130042212003242&w=2Disable ASPM when no _OSC control for PCIe services is granted
by the BIOS. This is to protect systems with a buggy BIOS that
did not set the ACPI FADT "ASPM Controls" bit even though the
underlying HW can't do ASPM.To turn "on" ASPM the minimum the BIOS needs to do:
1. Clear the ACPI FADT "ASPM Controls" bit.
2. Support _OSC appropriatelyThere is no _OSC Control bit for ASPM. However, we expect the BIOS to
support _OSC for a Root Bridge that originates a PCIe hierarchy. If this
is not the case - we are better off not enabling ASPM on that server.Commit 852972acff8f10f3a15679be2059bb94916cba5d (ACPI: Disable ASPM if the
Platform won't provide _OSC control for PCIe) describes the above scenario.
To quote verbatim from there:
[The PCI SIG documentation for the _OSC OS/firmware handshaking interface
states:"If the _OSC control method is absent from the scope of a host bridge
device, then the operating system must not enable or attempt to use any
features defined in this section for the hierarchy originated by the host
bridge."The obvious interpretation of this is that the OS should not attempt to use
PCIe hotplug, PME or AER - however, the specification also notes that an
_OSC method is *required* for PCIe hierarchies, and experimental validation
with An Alternative OS indicates that it doesn't use any PCIe functionality
if the _OSC method is missing. That arguably means we shouldn't be using
MSI or extended config space, but right now our problems seem to be limited
to vendors being surprised when ASPM gets enabled on machines when other
OSs refuse to do so. So, for now, let's just disable ASPM if the _OSC
method doesn't exist or refuses to hand over PCIe capability control.]Signed-off-by: Naga Chumbalkar
Cc: Rafael J. Wysocki
Cc: Matthew Garrett
Signed-off-by: Jesse Barnes -
v3 -> v2: Modified the text that describes the problem
v2 -> v1: Returned -EPERM
v1 : http://marc.info/?l=linux-pci&m=130013194803727&w=2For servers whose hardware cannot handle ASPM the BIOS ought to set the
FADT bit shown below:
In Sec 5.2.9.3 (IA-PC Boot Arch. Flags) of ACPI4.0a Specification, please
see Table 5-11:
PCIe ASPM Controls: If set, indicates to OSPM that it must not enable
OPSM ASPM control on this platform.However there are shipping servers whose BIOS did not set this bit. (An
example is the HP ProLiant DL385 G6. A Maintenance BIOS will fix that).
For such servers even if a call is made via pci_no_aspm(), based on _OSC
support in the BIOS, it may be too late because the ASPM code may have
already allocated and filled its "link_list".So if a user sets the ASPM "policy" to "powersave" via /sys then
pcie_aspm_set_policy() will run through the "link_list" and re-configure
ASPM policy on devices that advertise ASPM L0s/L1 capability:
# echo powersave > /sys/module/pcie_aspm/parameters/policy
# cat /sys/module/pcie_aspm/parameters/policy
default performance [powersave]That can cause NMIs since the hardware doesn't play well with ASPM:
[ 1651.906015] NMI: PCI system error (SERR) for reason b1 on CPU 0.
[ 1651.906015] Dazed and confused, but trying to continueIdeally, the BIOS should have set that FADT bit in the first place but we
could be more robust - especially given the fact that Windows doesn't
cause NMIs in the above scenario.There should be a sanity check to not allow a user to modify ASPM policy
when aspm_disabled is set.Signed-off-by: Naga Chumbalkar
Acked-by: Rafael J. Wysocki
Cc: Matthew Garrett
Signed-off-by: Jesse Barnes -
v3 -> v2: Moved ASPM enabling logic to pci_set_power_state()
v2 -> v1: Preserved the logic in pci_raw_set_power_state()
: Added ASPM enabling logic after scanning Root Bridge
: http://marc.info/?l=linux-pci&m=130046996216391&w=2
v1 : http://marc.info/?l=linux-pci&m=130013164703283&w=2The assumption made in commit 41cd766b065970ff6f6c89dd1cf55fa706c84a3d
(PCI: Don't enable aspm before drivers have had a chance to veto it) that
pci_enable_device() will result in re-configuring ASPM when aspm_policy is
POWERSAVE is no longer valid. This is due to commit
97c145f7c87453cec90e91238fba5fe2c1561b32 (PCI: read current power state
at enable time) which resets dev->current_state to D0. Due to this the
call to pcie_aspm_pm_state_change() is never made. Note the equality check
(below) that returns early:
./drivers/pci/pci.c: pci_raw_set_pci_power_state()
546 /* Check if we're already there */
547 if (dev->current_state == state)
548 return 0;Therefore OSPM never configures the PCIe links for ASPM to turn them "on".
Fix it by configuring ASPM from the pci_enable_device() code path. This
also allows a driver such as the e1000e networking driver a chance to
disable ASPM (L0s, L1), if need be, prior to enabling the device. A
driver may perform this action if the device is known to mis-behave
wrt ASPM.Signed-off-by: Naga Chumbalkar
Acked-by: Rafael J. Wysocki
Cc: Matthew Garrett
Signed-off-by: Jesse Barnes -
We need to distinguish the situation in which ASPM support is
disabled from the command line or through .config from the situation
in which it is disabled, because the hardware or BIOS can't handle
it. In the former case we should not report ASPM support to the BIOS
through ACPI _OSC, but in the latter case we should do that.Introduce pcie_aspm_support_enabled() that can be used by
acpi_pci_root_add() to determine whether or not it should report ASPM
support to the BIOS through _OSC.Cc: stable@kernel.org
References: https://bugzilla.kernel.org/show_bug.cgi?id=29722
References: https://bugzilla.kernel.org/show_bug.cgi?id=20232
Reported-and-tested-by: Ortwin Glück
Reviewed-by: Kenji Kaneshige
Tested-by: Kenji Kaneshige
Signed-off-by: Rafael J. Wysocki
Signed-off-by: Jesse Barnes
05 Mar, 2011
1 commit
-
I have several systems which have the same problem: The PCIe AER
corrected and uncorrected masks have all the error bits set. This
results in the inablility to test with the aer_inject module & utility
on those systems.Add the 'aer_mask_override' module parameter which will override the
corrected or uncorrected masks for a PCI device. The mask will have the
bit corresponding to the status passed into the aer_inject() function.After this patch it is possible to successfully use the aer_inject
utility on those PCI slots.Successfully tested by me on a Dell and Intel whitebox which exhibited
the mask problem.Signed-off-by: Prarit Bhargava
Signed-off-by: Jesse Barnes
21 Jan, 2011
1 commit
-
The meaning of CONFIG_EMBEDDED has long since been obsoleted; the option
is used to configure any non-standard kernel with a much larger scope than
only small devices.This patch renames the option to CONFIG_EXPERT in init/Kconfig and fixes
references to the option throughout the kernel. A new CONFIG_EMBEDDED
option is added that automatically selects CONFIG_EXPERT when enabled and
can be used in the future to isolate options that should only be
considered for embedded systems (RISC architectures, SLOB, etc).Calling the option "EXPERT" more accurately represents its intention: only
expert users who understand the impact of the configuration changes they
are making should enable it.Reviewed-by: Ingo Molnar
Acked-by: David Woodhouse
Signed-off-by: David Rientjes
Cc: Greg KH
Cc: "David S. Miller"
Cc: Jens Axboe
Cc: Arnd Bergmann
Cc: Robin Holt
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
15 Jan, 2011
2 commits
-
Make wakeup events be reported by the PCI subsystem before attempting to
resume devices or queuing up runtime resume requests for them, because
wakeup events should be reported as soon as they have been detected.Signed-off-by: Rafael J. Wysocki
Signed-off-by: Jesse Barnes -
Move the evaluation of acpi_pci_osc_control_set() (to request control of
PCI Express native features) into acpi_pci_root_add() to avoid calling
it many times for the same root complex with the same arguments.
Additionally, check if all of the requisite _OSC support bits are set
before calling acpi_pci_osc_control_set() for a given root complex.References: https://bugzilla.kernel.org/show_bug.cgi?id=20232
Reported-by: Ozan Caglayan
Tested-by: Ozan Caglayan
Signed-off-by: Rafael J. Wysocki
Signed-off-by: Jesse Barnes
24 Dec, 2010
2 commits
-
I noticed that PCI Express PMEs don't work on my Toshiba Portege R500
after the system has been woken up from a sleep state by a PME
(through Wake-on-LAN). After some investigation it turned out that
the BIOS didn't clear the Root PME Status bit in the root port that
received the wakeup PME and since the Requester ID was also set in
the port's Root Status register, any subsequent PMEs didn't trigger
interrupts.This problem can be avoided by clearing the Root PME Status bits in
all PCI Express root ports during early resume. For this purpose,
add an early resume routine to the PCIe port driver and make this
driver be always registered, even if pci_ports_disable is set (in
which case the driver's only function is to provide the early
resume callback).Signed-off-by: Rafael J. Wysocki
Signed-off-by: Jesse Barnes -
We currently refuse to touch the ASPM registers if the BIOS tells us that
ASPM isn't supported. This can cause problems if the BIOS has (for any
reason) enabled ASPM on some devices anyway. Change the code such that we
explicitly clear ASPM if the FADT indicates that ASPM isn't supported,
and make sure we tidy up appropriately on device removal in order to deal
with the hotplug case. If ASPM is disabled because the BIOS doesn't hand
over control then we won't touch the registers.Signed-off-by: Matthew Garrett
Signed-off-by: Jesse Barnes
29 Oct, 2010
1 commit
-
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (27 commits)
x86: allocate space within a region top-down
x86: update iomem_resource end based on CPU physical address capabilities
x86/PCI: allocate space from the end of a region, not the beginning
PCI: allocate bus resources from the top down
resources: support allocating space within a region from the top down
resources: handle overflow when aligning start of available area
resources: ensure callback doesn't allocate outside available space
resources: factor out resource_clip() to simplify find_resource()
resources: add a default alignf to simplify find_resource()
x86/PCI: MMCONFIG: fix region end calculation
PCI: Add support for polling PME state on suspended legacy PCI devices
PCI: Export some PCI PM functionality
PCI: fix message typo
PCI: log vendor/device ID always
PCI: update Intel chipset names and defines
PCI: use new ccflags variable in Makefile
PCI: add PCI_MSIX_TABLE/PBA defines
PCI: add PCI vendor id for STmicroelectronics
x86/PCI: irq and pci_ids patch for Intel Patsburg DeviceIDs
PCI: OLPC: Only enable PCI configuration type override on XO-1
...
16 Oct, 2010
2 commits
-
There is a design issue related to PCIe AER and _OSC that the BIOS
may be asked to grant control of the AER service even if some
Hardware Error Source Table (HEST) entries contain information
meaning that the BIOS really should control it. Namely,
pcie_port_acpi_setup() calls pcie_aer_get_firmware_first() that
determines whether or not the AER service should be controlled by
the BIOS on the basis of the HEST information for the given PCIe
port. The BIOS is asked to grant control of the AER service for
a PCIe Root Complex if pcie_aer_get_firmware_first() returns 'false'
for at least one root port in that complex, even if all of the other
root ports' HEST entries have the FIRMWARE_FIRST flag set (and none
of them has the GLOBAL flag set). However, if the AER service is
controlled by the kernel, that may interfere with the BIOS' handling
of the error sources having the FIRMWARE_FIRST flag. Moreover,
there may be PCIe endpoints that have the FIRMWARE_FIRST flag set in
HEST and are attached to the root ports in question, in which case it
also may be unsafe to ask the BIOS for control of the AER service.For this reason, introduce a function checking if there's at least
one PCIe-related HEST entry with the FIRMWARE_FIRST flag set and
disable the native AER service altogether if this function returns
'true'.Signed-off-by: Rafael J. Wysocki
Signed-off-by: Jesse Barnes -
quiet the warning about use of uninitialized e_src in
aer_isr() e_src is initialized by get_e_source()Signed-off-by: Bill Pemberton
Signed-off-by: Jesse Barnes
15 Oct, 2010
1 commit
-
All file_operations should get a .llseek operation so we can make
nonseekable_open the default for future file operations without a
.llseek pointer.The three cases that we can automatically detect are no_llseek, seq_lseek
and default_llseek. For cases where we can we can automatically prove that
the file offset is always ignored, we use noop_llseek, which maintains
the current behavior of not returning an error from a seek.New drivers should normally not use noop_llseek but instead use no_llseek
and call nonseekable_open at open time. Existing drivers can be converted
to do the same when the maintainer knows for certain that no user code
relies on calling seek on the device file.The generated code is often incorrectly indented and right now contains
comments that clarify for each added line why a specific variant was
chosen. In the version that gets submitted upstream, the comments will
be gone and I will manually fix the indentation, because there does not
seem to be a way to do that using coccinelle.Some amount of new code is currently sitting in linux-next that should get
the same modifications, which I will do at the end of the merge window.Many thanks to Julia Lawall for helping me learn to write a semantic
patch that does all this.===== begin semantic patch =====
// This adds an llseek= method to all file operations,
// as a preparation for making no_llseek the default.
//
// The rules are
// - use no_llseek explicitly if we do nonseekable_open
// - use seq_lseek for sequential files
// - use default_llseek if we know we access f_pos
// - use noop_llseek if we know we don't access f_pos,
// but we still want to allow users to call lseek
//
@ open1 exists @
identifier nested_open;
@@
nested_open(...)
{}
@ open exists@
identifier open_f;
identifier i, f;
identifier open1.nested_open;
@@
int open_f(struct inode *i, struct file *f)
{}
@ read disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{}
@ read_no_fpos disable optional_qualifier exists @
identifier read_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
{
... when != off
}@ write @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
expression E;
identifier func;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{}
@ write_no_fpos @
identifier write_f;
identifier f, p, s, off;
type ssize_t, size_t, loff_t;
@@
ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
{
... when != off
}@ fops0 @
identifier fops;
@@
struct file_operations fops = {
...
};@ has_llseek depends on fops0 @
identifier fops0.fops;
identifier llseek_f;
@@
struct file_operations fops = {
...
.llseek = llseek_f,
...
};@ has_read depends on fops0 @
identifier fops0.fops;
identifier read_f;
@@
struct file_operations fops = {
...
.read = read_f,
...
};@ has_write depends on fops0 @
identifier fops0.fops;
identifier write_f;
@@
struct file_operations fops = {
...
.write = write_f,
...
};@ has_open depends on fops0 @
identifier fops0.fops;
identifier open_f;
@@
struct file_operations fops = {
...
.open = open_f,
...
};// use no_llseek if we call nonseekable_open
////////////////////////////////////////////
@ nonseekable1 depends on !has_llseek && has_open @
identifier fops0.fops;
identifier nso ~= "nonseekable_open";
@@
struct file_operations fops = {
... .open = nso, ...
+.llseek = no_llseek, /* nonseekable */
};@ nonseekable2 depends on !has_llseek @
identifier fops0.fops;
identifier open.open_f;
@@
struct file_operations fops = {
... .open = open_f, ...
+.llseek = no_llseek, /* open uses nonseekable */
};// use seq_lseek for sequential files
/////////////////////////////////////
@ seq depends on !has_llseek @
identifier fops0.fops;
identifier sr ~= "seq_read";
@@
struct file_operations fops = {
... .read = sr, ...
+.llseek = seq_lseek, /* we have seq_read */
};// use default_llseek if there is a readdir
///////////////////////////////////////////
@ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier readdir_e;
@@
// any other fop is used that changes pos
struct file_operations fops = {
... .readdir = readdir_e, ...
+.llseek = default_llseek, /* readdir is present */
};// use default_llseek if at least one of read/write touches f_pos
/////////////////////////////////////////////////////////////////
@ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read.read_f;
@@
// read fops use offset
struct file_operations fops = {
... .read = read_f, ...
+.llseek = default_llseek, /* read accesses f_pos */
};@ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write.write_f;
@@
// write fops use offset
struct file_operations fops = {
... .write = write_f, ...
+ .llseek = default_llseek, /* write accesses f_pos */
};// Use noop_llseek if neither read nor write accesses f_pos
///////////////////////////////////////////////////////////@ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
identifier write_no_fpos.write_f;
@@
// write fops use offset
struct file_operations fops = {
...
.write = write_f,
.read = read_f,
...
+.llseek = noop_llseek, /* read and write both use no f_pos */
};@ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier write_no_fpos.write_f;
@@
struct file_operations fops = {
... .write = write_f, ...
+.llseek = noop_llseek, /* write uses no f_pos */
};@ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
identifier read_no_fpos.read_f;
@@
struct file_operations fops = {
... .read = read_f, ...
+.llseek = noop_llseek, /* read uses no f_pos */
};@ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
identifier fops0.fops;
@@
struct file_operations fops = {
...
+.llseek = noop_llseek, /* no read or write fn */
};
===== End semantic patch =====Signed-off-by: Arnd Bergmann
Cc: Julia Lawall
Cc: Christoph Hellwig
25 Aug, 2010
7 commits
-
The PCIe port driver's module exit routine is never used, so drop it.
Signed-off-by: Kenji Kaneshige
Signed-off-by: Rafael J. Wysocki
Reviewed-by: Hidetoshi Seto
Signed-off-by: Jesse Barnes -
The PCIe PME code only consists of one file, so it doesn't need to
occupy its own directory. Move it to drivers/pci/pcie/pme.c and
remove the contents of drivers/pci/pcie/pme .Signed-off-by: Rafael J. Wysocki
Signed-off-by: Jesse Barnes -
In principle PCIe port services may be enabled by the BIOS, so it's
better to disable them during port initialization to avoid spurious
events from being generated.Signed-off-by: Rafael J. Wysocki
Reviewed-by: Hidetoshi Seto
Signed-off-by: Jesse Barnes -
After commit 852972acff8f10f3a15679be2059bb94916cba5d (ACPI: Disable
ASPM if the platform won't provide _OSC control for PCIe) control of
the PCIe Capability Structure is unconditionally requested by
acpi_pci_root_add(), which in principle may cause problems to
happen in two ways. First, the BIOS may refuse to give control of
the PCIe Capability Structure if it is not asked for any of the
_OSC features depending on it at the same time. Second, the BIOS may
assume that control of the _OSC features depending on the PCIe
Capability Structure will be requested in the future and may behave
incorrectly if that doesn't happen. For this reason, control of
the PCIe Capability Structure should always be requested along with
control of any other _OSC features that may depend on it (ie. PCIe
native PME, PCIe native hot-plug, PCIe AER).Rework the PCIe port driver so that (1) it checks which native PCIe
port services can be enabled, according to the BIOS, and (2) it
requests control of all these services simultaneously. In
particular, this causes pcie_portdrv_probe() to fail if the BIOS
refuses to grant control of the PCIe Capability Structure, which
means that no native PCIe port services can be enabled for the PCIe
Root Complex the given port belongs to. If that happens, ASPM is
disabled to avoid problems with mishandling it by the part of the
PCIe hierarchy for which control of the PCIe Capability Structure
has not been received.Make it possible to override this behavior using 'pcie_ports=native'
(use the PCIe native services regardless of the BIOS response to the
control request), or 'pcie_ports=compat' (do not use the PCIe native
services at all).Accordingly, rework the existing PCIe port service drivers so that
they don't request control of the services directly.Signed-off-by: Rafael J. Wysocki
Signed-off-by: Jesse Barnes -
It is possible that the BIOS will not grant control of all _OSC
features requested via acpi_pci_osc_control_set(), so it is
recommended to negotiate the final set of _OSC features with the
query flag set before calling _OSC to request control of these
features.To implement it, rework acpi_pci_osc_control_set() so that the caller
can specify the mask of _OSC control bits to negotiate and the mask
of _OSC control bits that are absolutely necessary to it. Then,
acpi_pci_osc_control_set() will run _OSC queries in a loop until
the mask of _OSC control bits returned by the BIOS is equal to the
mask passed to it. Also, before running the _OSC request
acpi_pci_osc_control_set() will check if the caller's required
control bits are present in the final mask.Using this mechanism we will be able to avoid situations in which the
BIOS doesn't grant control of certain _OSC features, because they
depend on some other _OSC features that have not been requested.Signed-off-by: Rafael J. Wysocki
Signed-off-by: Jesse Barnes -
Introduce kernel command line switch pcie_ports= allowing one to
disable all of the native PCIe port services, so that PCIe ports
are treated like PCI-to-PCI bridges.Signed-off-by: Rafael J. Wysocki
Signed-off-by: Jesse Barnes -
Introduce a function allowing the caller to check whether to try to
enable PCIe AER.Signed-off-by: Rafael J. Wysocki
Signed-off-by: Jesse Barnes
07 Aug, 2010
1 commit
-
* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6: (30 commits)
PCI: update for owner removal from struct device_attribute
PCI: Fix warnings when CONFIG_DMI unset
PCI: Do not run NVidia quirks related to MSI with MSI disabled
x86/PCI: use for_each_pci_dev()
PCI: use for_each_pci_dev()
PCI: MSI: Restore read_msi_msg_desc(); add get_cached_msi_msg_desc()
PCI: export SMBIOS provided firmware instance and label to sysfs
PCI: Allow read/write access to sysfs I/O port resources
x86/PCI: use host bridge _CRS info on ASRock ALiveSATA2-GLAN
PCI: remove unused HAVE_ARCH_PCI_SET_DMA_MAX_SEGMENT_{SIZE|BOUNDARY}
PCI: disable mmio during bar sizing
PCI: MSI: Remove unsafe and unnecessary hardware access
PCI: Default PCIe ASPM control to on and require !EMBEDDED to disable
PCI: kernel oops on access to pci proc file while hot-removal
PCI: pci-sysfs: remove casts from void*
ACPI: Disable ASPM if the platform won't provide _OSC control for PCIe
PCI hotplug: make sure child bridges are enabled at hotplug time
PCI hotplug: shpchp: Removed check for hotplug of display devices
PCI hotplug: pciehp: Fixed return value sign for pciehp_unconfigure_device
PCI: Don't enable aspm before drivers have had a chance to veto it
...
31 Jul, 2010
3 commits
-
The CONFIG_PCIEASPM option is confusing and potentially dangerous. ASPM is
a hardware mediated feature rather than one under direct OS control, and
even if the config option is disabled the system firmware may have turned
on ASPM on various bits of hardware. This can cause problems later -
various hardware that claims to support ASPM does a poor job of it and may
hang or cause other difficulties. The kernel is able to recognise this in
many cases and disable the ASPM functionality, but only if CONFIG_PCIEASPM
is enabled.Given that in its default configuration this option will either leave the
hardware as it was originally or disable hardware functionality that may
cause problems, it should by default y. The only reason to disable it
ought to be to reduce code size, so make it dependent on CONFIG_EMBEDDED.Signed-off-by: Matthew Garrett
Cc: lrodriguez@atheros.com
Cc: maximlevitsky@gmail.com
Signed-off-by: Jesse Barnes -
The aspm code will currently set the configured aspm policy before drivers
have had an opportunity to indicate that their hardware doesn't support it.
Unfortunately, putting some hardware in L0 or L1 can result in the hardware
no longer responding to any requests, even after aspm is disabled. It makes
more sense to leave aspm policy at the BIOS defaults at initial setup time,
reconfiguring it after pci_enable_device() is called. This allows the
driver to blacklist individual devices beforehand.Reviewed-by: Kenji Kaneshige
Signed-off-by: Matthew Garrett
Signed-off-by: Jesse Barnes -
Some compiler generates following warnings:
In function 'aer_isr':
warning: 'e_src.id' may be used uninitialized in this function
warning: 'e_src.status' may be used uninitialized in this functionAvoid status flag "int ret" and return constants instead, so that
gcc sees the return value matching "it is initialized" better.Acked-by: Hidetoshi Seto
Signed-off-by: Linus Torvalds
Signed-off-by: Hidetoshi Seto
Signed-off-by: Jesse Barnes
19 Jul, 2010
1 commit
-
One of the arguments during the suspend blockers discussion was that
the mainline kernel didn't contain any mechanisms making it possible
to avoid races between wakeup and system suspend.Generally, there are two problems in that area. First, if a wakeup
event occurs exactly when /sys/power/state is being written to, it
may be delivered to user space right before the freezer kicks in, so
the user space consumer of the event may not be able to process it
before the system is suspended. Second, if a wakeup event occurs
after user space has been frozen, it is not generally guaranteed that
the ongoing transition of the system into a sleep state will be
aborted.To address these issues introduce a new global sysfs attribute,
/sys/power/wakeup_count, associated with a running counter of wakeup
events and three helper functions, pm_stay_awake(), pm_relax(), and
pm_wakeup_event(), that may be used by kernel subsystems to control
the behavior of this attribute and to request the PM core to abort
system transitions into a sleep state already in progress.The /sys/power/wakeup_count file may be read from or written to by
user space. Reads will always succeed (unless interrupted by a
signal) and return the current value of the wakeup events counter.
Writes, however, will only succeed if the written number is equal to
the current value of the wakeup events counter. If a write is
successful, it will cause the kernel to save the current value of the
wakeup events counter and to abort the subsequent system transition
into a sleep state if any wakeup events are reported after the write
has returned.[The assumption is that before writing to /sys/power/state user space
will first read from /sys/power/wakeup_count. Next, user space
consumers of wakeup events will have a chance to acknowledge or
veto the upcoming system transition to a sleep state. Finally, if
the transition is allowed to proceed, /sys/power/wakeup_count will
be written to and if that succeeds, /sys/power/state will be written
to as well. Still, if any wakeup events are reported to the PM core
by kernel subsystems after that point, the transition will be
aborted.]Additionally, put a wakeup events counter into struct dev_pm_info and
make these per-device wakeup event counters available via sysfs,
so that it's possible to check the activity of various wakeup event
sources within the kernel.To illustrate how subsystems can use pm_wakeup_event(), make the
low-level PCI runtime PM wakeup-handling code use it.Signed-off-by: Rafael J. Wysocki
Acked-by: Jesse Barnes
Acked-by: Greg Kroah-Hartman
Acked-by: markgross
Reviewed-by: Alan Stern
19 Jun, 2010
1 commit
-
Commit c7f486567c1d0acd2e4166c47069835b9f75e77b
(PCI PM: PCIe PME root port service driver) causes the native PCIe
PME signaling to be used by default, if the BIOS allows the kernel to
control the standard configuration registers of PCIe root ports.
However, the native PCIe PME is coupled to the native PCIe hotplug
and calling pcie_pme_acpi_setup() makes some BIOSes expect that
the native PCIe hotplug will be used as well. That, in turn, causes
problems to appear on systems where the PCIe hotplug driver is not
loaded. The usual symptom, as reported by Jaroslav Kameník and
others, is that the ACPI GPE associated with PCIe hotplug keeps
firing continuously causing kacpid to take substantial percentage
of CPU time.To work around this issue, change the default so that the native
PCIe PME signaling is only used if directly requested with the help
of the pcie_pme= command line switch.Fixes https://bugzilla.kernel.org/show_bug.cgi?id=15924 , which is
a listed regression from 2.6.33.Signed-off-by: Rafael J. Wysocki
Reported-by: Jaroslav Kameník
Tested-by: Antoni Grzymala
Signed-off-by: Jesse Barnes
29 May, 2010
1 commit
-
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (27 commits)
ACPI: Don't let acpi_pad needlessly mark TSC unstable
drivers/acpi/sleep.h: Checkpatch cleanup
ACPI: Minor cleanup eliminating redundant PMTIMER_TICKS to NS conversion
ACPI: delete unused c-state promotion/demotion data strucutures
ACPI: video: fix acpi_backlight=video
ACPI: EC: Use kmemdup
drivers/acpi: use kasprintf
ACPI, APEI, EINJ injection parameters support
Add x64 support to debugfs
ACPI, APEI, Use ERST for persistent storage of MCE
ACPI, APEI, Error Record Serialization Table (ERST) support
ACPI, APEI, Generic Hardware Error Source memory error support
ACPI, APEI, UEFI Common Platform Error Record (CPER) header
Unified UUID/GUID definition
ACPI Hardware Error Device (PNP0C33) support
ACPI, APEI, PCIE AER, use general HEST table parsing in AER firmware_first setup
ACPI, APEI, Document for APEI
ACPI, APEI, EINJ support
ACPI, APEI, HEST table parsing
ACPI, APEI, APEI supporting infrastructure
...