linux_old1/include/linux/irq.h

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#ifndef _LINUX_IRQ_H
#define _LINUX_IRQ_H
/*
* Please do not include this file in generic code. There is currently
* no requirement for any architecture to implement anything held
* within this file.
*
* Thanks. --rmk
*/
#include <linux/smp.h>
#ifndef CONFIG_S390
#include <linux/linkage.h>
#include <linux/cache.h>
#include <linux/spinlock.h>
#include <linux/cpumask.h>
#include <linux/gfp.h>
#include <linux/irqreturn.h>
#include <linux/irqnr.h>
#include <linux/errno.h>
#include <linux/topology.h>
#include <linux/wait.h>
#include <asm/irq.h>
#include <asm/ptrace.h>
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 21:55:46 +08:00
#include <asm/irq_regs.h>
struct irq_desc;
typedef void (*irq_flow_handler_t)(unsigned int irq,
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 21:55:46 +08:00
struct irq_desc *desc);
/*
* IRQ line status.
[PATCH] irq-flags: consolidate flags for request_irq The recent interrupt rework introduced bit value conflicts with sparc. Instead of introducing new architecture flags mess, move the interrupt SA_ flags out of the signal namespace and replace them by interrupt related flags. This allows to remove the obsolete SA_INTERRUPT flag and clean up the bit field values. This patch: Move the interrupt related SA_ flags out of linux/signal.h and rename them to IRQF_ . This moves the interrupt related flags out of the signal namespace and allows to remove the architecture dependencies. SA_INTERRUPT is not needed by userspace and glibc so it can be removed safely. The existing SA_ constants are kept for easy transition and will be removed after a 6 month grace period. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Jaroslav Kysela <perex@suse.cz> Cc: Takashi Iwai <tiwai@suse.de> Cc: "Antonino A. Daplas" <adaplas@pol.net> Cc: Greg KH <greg@kroah.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Jeff Garzik <jeff@garzik.org> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Karsten Keil <kkeil@suse.de> Cc: Jody McIntyre <scjody@modernduck.com> Cc: Ben Collins <bcollins@debian.org> Cc: Stefan Richter <stefanr@s5r6.in-berlin.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl> Cc: Dave Airlie <airlied@linux.ie> Cc: Jens Axboe <axboe@suse.de> Cc: Chris Zankel <chris@zankel.net> Cc: Andi Kleen <ak@muc.de> Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp> Cc: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greg Ungerer <gerg@uclinux.org> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: David Howells <dhowells@redhat.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Richard Henderson <rth@twiddle.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02 10:29:03 +08:00
*
* Bits 0-7 are reserved for the IRQF_* bits in linux/interrupt.h
[PATCH] irq-flags: consolidate flags for request_irq The recent interrupt rework introduced bit value conflicts with sparc. Instead of introducing new architecture flags mess, move the interrupt SA_ flags out of the signal namespace and replace them by interrupt related flags. This allows to remove the obsolete SA_INTERRUPT flag and clean up the bit field values. This patch: Move the interrupt related SA_ flags out of linux/signal.h and rename them to IRQF_ . This moves the interrupt related flags out of the signal namespace and allows to remove the architecture dependencies. SA_INTERRUPT is not needed by userspace and glibc so it can be removed safely. The existing SA_ constants are kept for easy transition and will be removed after a 6 month grace period. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Jaroslav Kysela <perex@suse.cz> Cc: Takashi Iwai <tiwai@suse.de> Cc: "Antonino A. Daplas" <adaplas@pol.net> Cc: Greg KH <greg@kroah.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Jeff Garzik <jeff@garzik.org> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Karsten Keil <kkeil@suse.de> Cc: Jody McIntyre <scjody@modernduck.com> Cc: Ben Collins <bcollins@debian.org> Cc: Stefan Richter <stefanr@s5r6.in-berlin.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl> Cc: Dave Airlie <airlied@linux.ie> Cc: Jens Axboe <axboe@suse.de> Cc: Chris Zankel <chris@zankel.net> Cc: Andi Kleen <ak@muc.de> Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp> Cc: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greg Ungerer <gerg@uclinux.org> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: David Howells <dhowells@redhat.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Richard Henderson <rth@twiddle.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02 10:29:03 +08:00
*
* IRQ types
*/
[PATCH] irq-flags: consolidate flags for request_irq The recent interrupt rework introduced bit value conflicts with sparc. Instead of introducing new architecture flags mess, move the interrupt SA_ flags out of the signal namespace and replace them by interrupt related flags. This allows to remove the obsolete SA_INTERRUPT flag and clean up the bit field values. This patch: Move the interrupt related SA_ flags out of linux/signal.h and rename them to IRQF_ . This moves the interrupt related flags out of the signal namespace and allows to remove the architecture dependencies. SA_INTERRUPT is not needed by userspace and glibc so it can be removed safely. The existing SA_ constants are kept for easy transition and will be removed after a 6 month grace period. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@elte.hu> Cc: "David S. Miller" <davem@davemloft.net> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: "Randy.Dunlap" <rdunlap@xenotime.net> Cc: Jaroslav Kysela <perex@suse.cz> Cc: Takashi Iwai <tiwai@suse.de> Cc: "Antonino A. Daplas" <adaplas@pol.net> Cc: Greg KH <greg@kroah.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: James Bottomley <James.Bottomley@steeleye.com> Cc: Kyle McMartin <kyle@mcmartin.ca> Cc: Jeff Garzik <jeff@garzik.org> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Cc: Karsten Keil <kkeil@suse.de> Cc: Jody McIntyre <scjody@modernduck.com> Cc: Ben Collins <bcollins@debian.org> Cc: Stefan Richter <stefanr@s5r6.in-berlin.de> Cc: Alan Cox <alan@lxorguk.ukuu.org.uk> Cc: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl> Cc: Dave Airlie <airlied@linux.ie> Cc: Jens Axboe <axboe@suse.de> Cc: Chris Zankel <chris@zankel.net> Cc: Andi Kleen <ak@muc.de> Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp> Cc: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Roman Zippel <zippel@linux-m68k.org> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greg Ungerer <gerg@uclinux.org> Cc: "Luck, Tony" <tony.luck@intel.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: David Howells <dhowells@redhat.com> Cc: Mikael Starvik <starvik@axis.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Richard Henderson <rth@twiddle.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-02 10:29:03 +08:00
#define IRQ_TYPE_NONE 0x00000000 /* Default, unspecified type */
#define IRQ_TYPE_EDGE_RISING 0x00000001 /* Edge rising type */
#define IRQ_TYPE_EDGE_FALLING 0x00000002 /* Edge falling type */
#define IRQ_TYPE_EDGE_BOTH (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING)
#define IRQ_TYPE_LEVEL_HIGH 0x00000004 /* Level high type */
#define IRQ_TYPE_LEVEL_LOW 0x00000008 /* Level low type */
#define IRQ_TYPE_SENSE_MASK 0x0000000f /* Mask of the above */
#define IRQ_TYPE_PROBE 0x00000010 /* Probing in progress */
/* Internal flags */
#define IRQ_INPROGRESS 0x00000100 /* IRQ handler active - do not enter! */
#define IRQ_DISABLED 0x00000200 /* IRQ disabled - do not enter! */
#define IRQ_PENDING 0x00000400 /* IRQ pending - replay on enable */
#define IRQ_REPLAY 0x00000800 /* IRQ has been replayed but not acked yet */
#define IRQ_AUTODETECT 0x00001000 /* IRQ is being autodetected */
#define IRQ_WAITING 0x00002000 /* IRQ not yet seen - for autodetection */
#define IRQ_LEVEL 0x00004000 /* IRQ level triggered */
#define IRQ_MASKED 0x00008000 /* IRQ masked - shouldn't be seen again */
#define IRQ_PER_CPU 0x00010000 /* IRQ is per CPU */
#define IRQ_NOPROBE 0x00020000 /* IRQ is not valid for probing */
#define IRQ_NOREQUEST 0x00040000 /* IRQ cannot be requested */
#define IRQ_NOAUTOEN 0x00080000 /* IRQ will not be enabled on request irq */
#define IRQ_WAKEUP 0x00100000 /* IRQ triggers system wakeup */
#define IRQ_MOVE_PENDING 0x00200000 /* need to re-target IRQ destination */
#define IRQ_NO_BALANCING 0x00400000 /* IRQ is excluded from balancing */
#define IRQ_SPURIOUS_DISABLED 0x00800000 /* IRQ was disabled by the spurious trap */
#define IRQ_MOVE_PCNTXT 0x01000000 /* IRQ migration from process context */
#define IRQ_AFFINITY_SET 0x02000000 /* IRQ affinity was set from userspace*/
#define IRQ_SUSPENDED 0x04000000 /* IRQ has gone through suspend sequence */
genirq: Add oneshot support For threaded interrupt handlers we expect the hard interrupt handler part to mask the interrupt on the originating device. The interrupt line itself is reenabled after the hard interrupt handler has executed. This requires access to the originating device from hard interrupt context which is not always possible. There are devices which can only be accessed via a bus (i2c, spi, ...). The bus access requires thread context. For such devices we need to keep the interrupt line masked until the threaded handler has executed. Add a new flag IRQF_ONESHOT which allows drivers to request that the interrupt is not unmasked after the hard interrupt context handler has been executed and the thread has been woken. The interrupt line is unmasked after the thread handler function has been executed. Note that for now IRQF_ONESHOT cannot be used with IRQF_SHARED to avoid complex accounting mechanisms. For oneshot interrupts the primary handler simply returns IRQ_WAKE_THREAD and does nothing else. A generic implementation irq_default_primary_handler() is provided to avoid useless copies all over the place. It is automatically installed when request_threaded_irq() is called with handler=NULL and thread_fn!=NULL. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Trilok Soni <soni.trilok@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Brian Swetland <swetland@google.com> Cc: Joonyoung Shim <jy0922.shim@samsung.com> Cc: m.szyprowski@samsung.com Cc: t.fujak@samsung.com Cc: kyungmin.park@samsung.com, Cc: David Brownell <david-b@pacbell.net> Cc: Daniel Ribeiro <drwyrm@gmail.com> Cc: arve@android.com Cc: Barry Song <21cnbao@gmail.com>
2009-08-13 18:17:22 +08:00
#define IRQ_ONESHOT 0x08000000 /* IRQ is not unmasked after hardirq */
genirq: Support nested threaded irq handling Interrupt chips which are behind a slow bus (i2c, spi ...) and demultiplex other interrupt sources need to run their interrupt handler in a thread. The demultiplexed interrupt handlers need to run in thread context as well and need to finish before the demux handler thread can reenable the interrupt line. So the easiest way is to run the sub device handlers in the context of the demultiplexing handler thread. To avoid that a separate thread is created for the subdevices the function set_nested_irq_thread() is provided which sets the IRQ_NESTED_THREAD flag in the interrupt descriptor. A driver which calls request_threaded_irq() must not be aware of the fact that the threaded handler is called in the context of the demultiplexing handler thread. The setup code checks the IRQ_NESTED_THREAD flag which was set from the irq chip setup code and does not setup a separate thread for the interrupt. The primary function which is provided by the device driver is replaced by an internal dummy function which warns when it is called. For the demultiplexing handler a helper function handle_nested_irq() is provided which calls the demux interrupt thread function in the context of the caller and does the proper interrupt accounting and takes the interrupt disabled status of the demultiplexed subdevice into account. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Trilok Soni <soni.trilok@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Brian Swetland <swetland@google.com> Cc: Joonyoung Shim <jy0922.shim@samsung.com> Cc: m.szyprowski@samsung.com Cc: t.fujak@samsung.com Cc: kyungmin.park@samsung.com, Cc: David Brownell <david-b@pacbell.net> Cc: Daniel Ribeiro <drwyrm@gmail.com> Cc: arve@android.com Cc: Barry Song <21cnbao@gmail.com>
2009-08-13 19:21:38 +08:00
#define IRQ_NESTED_THREAD 0x10000000 /* IRQ is nested into another, no own handler thread */
#define IRQF_MODIFY_MASK \
(IRQ_TYPE_SENSE_MASK | IRQ_NOPROBE | IRQ_NOREQUEST | \
IRQ_NOAUTOEN | IRQ_MOVE_PCNTXT | IRQ_LEVEL)
#ifdef CONFIG_IRQ_PER_CPU
# define CHECK_IRQ_PER_CPU(var) ((var) & IRQ_PER_CPU)
# define IRQ_NO_BALANCING_MASK (IRQ_PER_CPU | IRQ_NO_BALANCING)
#else
# define CHECK_IRQ_PER_CPU(var) 0
# define IRQ_NO_BALANCING_MASK IRQ_NO_BALANCING
#endif
struct msi_desc;
/**
* struct irq_data - per irq and irq chip data passed down to chip functions
* @irq: interrupt number
* @node: node index useful for balancing
* @chip: low level interrupt hardware access
* @handler_data: per-IRQ data for the irq_chip methods
* @chip_data: platform-specific per-chip private data for the chip
* methods, to allow shared chip implementations
* @msi_desc: MSI descriptor
* @affinity: IRQ affinity on SMP
* @irq_2_iommu: iommu with this irq
*
* The fields here need to overlay the ones in irq_desc until we
* cleaned up the direct references and switched everything over to
* irq_data.
*/
struct irq_data {
unsigned int irq;
unsigned int node;
struct irq_chip *chip;
void *handler_data;
void *chip_data;
struct msi_desc *msi_desc;
#ifdef CONFIG_SMP
cpumask_var_t affinity;
#endif
#ifdef CONFIG_INTR_REMAP
struct irq_2_iommu *irq_2_iommu;
#endif
};
/**
* struct irq_chip - hardware interrupt chip descriptor
*
* @name: name for /proc/interrupts
* @startup: deprecated, replaced by irq_startup
* @shutdown: deprecated, replaced by irq_shutdown
* @enable: deprecated, replaced by irq_enable
* @disable: deprecated, replaced by irq_disable
* @ack: deprecated, replaced by irq_ack
* @mask: deprecated, replaced by irq_mask
* @mask_ack: deprecated, replaced by irq_mask_ack
* @unmask: deprecated, replaced by irq_unmask
* @eoi: deprecated, replaced by irq_eoi
* @end: deprecated, will go away with __do_IRQ()
* @set_affinity: deprecated, replaced by irq_set_affinity
* @retrigger: deprecated, replaced by irq_retrigger
* @set_type: deprecated, replaced by irq_set_type
* @set_wake: deprecated, replaced by irq_wake
* @bus_lock: deprecated, replaced by irq_bus_lock
* @bus_sync_unlock: deprecated, replaced by irq_bus_sync_unlock
*
* @irq_startup: start up the interrupt (defaults to ->enable if NULL)
* @irq_shutdown: shut down the interrupt (defaults to ->disable if NULL)
* @irq_enable: enable the interrupt (defaults to chip->unmask if NULL)
* @irq_disable: disable the interrupt
* @irq_ack: start of a new interrupt
* @irq_mask: mask an interrupt source
* @irq_mask_ack: ack and mask an interrupt source
* @irq_unmask: unmask an interrupt source
* @irq_eoi: end of interrupt
* @irq_set_affinity: set the CPU affinity on SMP machines
* @irq_retrigger: resend an IRQ to the CPU
* @irq_set_type: set the flow type (IRQ_TYPE_LEVEL/etc.) of an IRQ
* @irq_set_wake: enable/disable power-management wake-on of an IRQ
* @irq_bus_lock: function to lock access to slow bus (i2c) chips
* @irq_bus_sync_unlock:function to sync and unlock slow bus (i2c) chips
genirq: Add buslock support Some interrupt chips are connected to a "slow" bus (i2c, spi ...). The bus access needs to sleep and therefor cannot be called in atomic contexts. Some of the generic interrupt management functions like disable_irq(), enable_irq() ... call interrupt chip functions with the irq_desc->lock held and interrupts disabled. This does not work for such devices. Provide a separate synchronization mechanism for such interrupt chips. The irq_chip structure is extended by two optional functions (bus_lock and bus_sync_and_unlock). The idea is to serialize the bus access for those operations in the core code so that drivers which are behind that bus operated interrupt controller do not have to worry about it and just can use the normal interfaces. To achieve this we add two function pointers to the irq_chip: bus_lock and bus_sync_unlock. bus_lock() is called to serialize access to the interrupt controller bus. Now the core code can issue chip->mask/unmask ... commands without changing the fast path code at all. The chip implementation merily stores that information in a chip private data structure and returns. No bus interaction as these functions are called from atomic context. After that bus_sync_unlock() is called outside the atomic context. Now the chip implementation issues the bus commands, waits for completion and unlocks the interrupt controller bus. The irq_chip implementation as pseudo code: struct irq_chip_data { struct mutex mutex; unsigned int irq_offset; unsigned long mask; unsigned long mask_status; } static void bus_lock(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); mutex_lock(&data->mutex); } static void mask(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); irq -= data->irq_offset; data->mask |= (1 << irq); } static void unmask(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); irq -= data->irq_offset; data->mask &= ~(1 << irq); } static void bus_sync_unlock(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); if (data->mask != data->mask_status) { do_bus_magic_to_set_mask(data->mask); data->mask_status = data->mask; } mutex_unlock(&data->mutex); } The device drivers can use request_threaded_irq, free_irq, disable_irq and enable_irq as usual with the only restriction that the calls need to come from non atomic context. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Trilok Soni <soni.trilok@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Brian Swetland <swetland@google.com> Cc: Joonyoung Shim <jy0922.shim@samsung.com> Cc: m.szyprowski@samsung.com Cc: t.fujak@samsung.com Cc: kyungmin.park@samsung.com, Cc: David Brownell <david-b@pacbell.net> Cc: Daniel Ribeiro <drwyrm@gmail.com> Cc: arve@android.com Cc: Barry Song <21cnbao@gmail.com>
2009-08-13 18:17:48 +08:00
*
* @release: release function solely used by UML
*/
struct irq_chip {
const char *name;
#ifndef CONFIG_GENERIC_HARDIRQS_NO_DEPRECATED
unsigned int (*startup)(unsigned int irq);
void (*shutdown)(unsigned int irq);
void (*enable)(unsigned int irq);
void (*disable)(unsigned int irq);
void (*ack)(unsigned int irq);
void (*mask)(unsigned int irq);
void (*mask_ack)(unsigned int irq);
void (*unmask)(unsigned int irq);
void (*eoi)(unsigned int irq);
void (*end)(unsigned int irq);
int (*set_affinity)(unsigned int irq,
const struct cpumask *dest);
int (*retrigger)(unsigned int irq);
int (*set_type)(unsigned int irq, unsigned int flow_type);
int (*set_wake)(unsigned int irq, unsigned int on);
genirq: Add buslock support Some interrupt chips are connected to a "slow" bus (i2c, spi ...). The bus access needs to sleep and therefor cannot be called in atomic contexts. Some of the generic interrupt management functions like disable_irq(), enable_irq() ... call interrupt chip functions with the irq_desc->lock held and interrupts disabled. This does not work for such devices. Provide a separate synchronization mechanism for such interrupt chips. The irq_chip structure is extended by two optional functions (bus_lock and bus_sync_and_unlock). The idea is to serialize the bus access for those operations in the core code so that drivers which are behind that bus operated interrupt controller do not have to worry about it and just can use the normal interfaces. To achieve this we add two function pointers to the irq_chip: bus_lock and bus_sync_unlock. bus_lock() is called to serialize access to the interrupt controller bus. Now the core code can issue chip->mask/unmask ... commands without changing the fast path code at all. The chip implementation merily stores that information in a chip private data structure and returns. No bus interaction as these functions are called from atomic context. After that bus_sync_unlock() is called outside the atomic context. Now the chip implementation issues the bus commands, waits for completion and unlocks the interrupt controller bus. The irq_chip implementation as pseudo code: struct irq_chip_data { struct mutex mutex; unsigned int irq_offset; unsigned long mask; unsigned long mask_status; } static void bus_lock(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); mutex_lock(&data->mutex); } static void mask(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); irq -= data->irq_offset; data->mask |= (1 << irq); } static void unmask(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); irq -= data->irq_offset; data->mask &= ~(1 << irq); } static void bus_sync_unlock(unsigned int irq) { struct irq_chip_data *data = get_irq_desc_chip_data(irq); if (data->mask != data->mask_status) { do_bus_magic_to_set_mask(data->mask); data->mask_status = data->mask; } mutex_unlock(&data->mutex); } The device drivers can use request_threaded_irq, free_irq, disable_irq and enable_irq as usual with the only restriction that the calls need to come from non atomic context. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Trilok Soni <soni.trilok@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Brian Swetland <swetland@google.com> Cc: Joonyoung Shim <jy0922.shim@samsung.com> Cc: m.szyprowski@samsung.com Cc: t.fujak@samsung.com Cc: kyungmin.park@samsung.com, Cc: David Brownell <david-b@pacbell.net> Cc: Daniel Ribeiro <drwyrm@gmail.com> Cc: arve@android.com Cc: Barry Song <21cnbao@gmail.com>
2009-08-13 18:17:48 +08:00
void (*bus_lock)(unsigned int irq);
void (*bus_sync_unlock)(unsigned int irq);
#endif
unsigned int (*irq_startup)(struct irq_data *data);
void (*irq_shutdown)(struct irq_data *data);
void (*irq_enable)(struct irq_data *data);
void (*irq_disable)(struct irq_data *data);
void (*irq_ack)(struct irq_data *data);
void (*irq_mask)(struct irq_data *data);
void (*irq_mask_ack)(struct irq_data *data);
void (*irq_unmask)(struct irq_data *data);
void (*irq_eoi)(struct irq_data *data);
int (*irq_set_affinity)(struct irq_data *data, const struct cpumask *dest, bool force);
int (*irq_retrigger)(struct irq_data *data);
int (*irq_set_type)(struct irq_data *data, unsigned int flow_type);
int (*irq_set_wake)(struct irq_data *data, unsigned int on);
void (*irq_bus_lock)(struct irq_data *data);
void (*irq_bus_sync_unlock)(struct irq_data *data);
/* Currently used only by UML, might disappear one day.*/
#ifdef CONFIG_IRQ_RELEASE_METHOD
void (*release)(unsigned int irq, void *dev_id);
#endif
};
/* This include will go away once we isolated irq_desc usage to core code */
#include <linux/irqdesc.h>
/*
* Pick up the arch-dependent methods:
*/
#include <asm/hw_irq.h>
struct irqaction;
extern int setup_irq(unsigned int irq, struct irqaction *new);
extern void remove_irq(unsigned int irq, struct irqaction *act);
#ifdef CONFIG_GENERIC_HARDIRQS
#if defined(CONFIG_SMP) && defined(CONFIG_GENERIC_PENDING_IRQ)
void move_native_irq(int irq);
[PATCH] genirq: irq: add moved_masked_irq Currently move_native_irq disables and renables the irq we are migrating to ensure we don't take that irq when we are actually doing the migration operation. Disabling the irq needs to happen but sometimes doing the work is move_native_irq is too late. On x86 with ioapics the irq move sequences needs to be: edge_triggered: mask irq. move irq. unmask irq. ack irq. level_triggered: mask irq. ack irq. move irq. unmask irq. We can easily perform the edge triggered sequence, with the current defintion of move_native_irq. However the level triggered case does not map well. For that I have added move_masked_irq, to allow me to disable the irqs around both the ack and the move. Q: Why have we not seen this problem earlier? A: The only symptom I have been able to reproduce is that if we change the vector before acknowleding an irq the wrong irq is acknowledged. Since we currently are not reprogramming the irq vector during migration no problems show up. We have to mask the irq before we acknowledge the irq or else we could hit a window where an irq is asserted just before we acknowledge it. Edge triggered irqs do not have this problem because acknowledgements do not propogate in the same way. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rajesh Shah <rajesh.shah@intel.com> Cc: Andi Kleen <ak@muc.de> Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 17:16:29 +08:00
void move_masked_irq(int irq);
#else
static inline void move_native_irq(int irq) { }
static inline void move_masked_irq(int irq) { }
#endif
[PATCH] x86/x86_64: deferred handling of writes to /proc/irqxx/smp_affinity When handling writes to /proc/irq, current code is re-programming rte entries directly. This is not recommended and could potentially cause chipset's to lockup, or cause missing interrupts. CONFIG_IRQ_BALANCE does this correctly, where it re-programs only when the interrupt is pending. The same needs to be done for /proc/irq handling as well. Otherwise user space irq balancers are really not doing the right thing. - Changed pending_irq_balance_cpumask to pending_irq_migrate_cpumask for lack of a generic name. - added move_irq out of IRQ_BALANCE, and added this same to X86_64 - Added new proc handler for write, so we can do deferred write at irq handling time. - Display of /proc/irq/XX/smp_affinity used to display CPU_MASKALL, instead it now shows only active cpu masks, or exactly what was set. - Provided a common move_irq implementation, instead of duplicating when using generic irq framework. Tested on i386/x86_64 and ia64 with CONFIG_PCI_MSI turned on and off. Tested UP builds as well. MSI testing: tbd: I have cards, need to look for a x-over cable, although I did test an earlier version of this patch. Will test in a couple days. Signed-off-by: Ashok Raj <ashok.raj@intel.com> Acked-by: Zwane Mwaikambo <zwane@holomorphy.com> Grudgingly-acked-by: Andi Kleen <ak@muc.de> Signed-off-by: Coywolf Qi Hunt <coywolf@lovecn.org> Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07 06:16:15 +08:00
extern int no_irq_affinity;
/* Handle irq action chains: */
extern irqreturn_t handle_IRQ_event(unsigned int irq, struct irqaction *action);
/*
* Built-in IRQ handlers for various IRQ types,
* callable via desc->handle_irq()
*/
extern void handle_level_irq(unsigned int irq, struct irq_desc *desc);
extern void handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc);
extern void handle_edge_irq(unsigned int irq, struct irq_desc *desc);
extern void handle_simple_irq(unsigned int irq, struct irq_desc *desc);
extern void handle_percpu_irq(unsigned int irq, struct irq_desc *desc);
extern void handle_bad_irq(unsigned int irq, struct irq_desc *desc);
extern void handle_nested_irq(unsigned int irq);
/* Handling of unhandled and spurious interrupts: */
extern void note_interrupt(unsigned int irq, struct irq_desc *desc,
irqreturn_t action_ret);
/* Enable/disable irq debugging output: */
extern int noirqdebug_setup(char *str);
/* Checks whether the interrupt can be requested by request_irq(): */
extern int can_request_irq(unsigned int irq, unsigned long irqflags);
/* Dummy irq-chip implementations: */
extern struct irq_chip no_irq_chip;
extern struct irq_chip dummy_irq_chip;
extern void
set_irq_chip_and_handler(unsigned int irq, struct irq_chip *chip,
irq_flow_handler_t handle);
extern void
set_irq_chip_and_handler_name(unsigned int irq, struct irq_chip *chip,
irq_flow_handler_t handle, const char *name);
extern void
__set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
const char *name);
/*
* Set a highlevel flow handler for a given IRQ:
*/
static inline void
set_irq_handler(unsigned int irq, irq_flow_handler_t handle)
{
__set_irq_handler(irq, handle, 0, NULL);
}
/*
* Set a highlevel chained flow handler for a given IRQ.
* (a chained handler is automatically enabled and set to
* IRQ_NOREQUEST and IRQ_NOPROBE)
*/
static inline void
set_irq_chained_handler(unsigned int irq,
irq_flow_handler_t handle)
{
__set_irq_handler(irq, handle, 1, NULL);
}
genirq: Support nested threaded irq handling Interrupt chips which are behind a slow bus (i2c, spi ...) and demultiplex other interrupt sources need to run their interrupt handler in a thread. The demultiplexed interrupt handlers need to run in thread context as well and need to finish before the demux handler thread can reenable the interrupt line. So the easiest way is to run the sub device handlers in the context of the demultiplexing handler thread. To avoid that a separate thread is created for the subdevices the function set_nested_irq_thread() is provided which sets the IRQ_NESTED_THREAD flag in the interrupt descriptor. A driver which calls request_threaded_irq() must not be aware of the fact that the threaded handler is called in the context of the demultiplexing handler thread. The setup code checks the IRQ_NESTED_THREAD flag which was set from the irq chip setup code and does not setup a separate thread for the interrupt. The primary function which is provided by the device driver is replaced by an internal dummy function which warns when it is called. For the demultiplexing handler a helper function handle_nested_irq() is provided which calls the demux interrupt thread function in the context of the caller and does the proper interrupt accounting and takes the interrupt disabled status of the demultiplexed subdevice into account. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com> Cc: Trilok Soni <soni.trilok@gmail.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Brian Swetland <swetland@google.com> Cc: Joonyoung Shim <jy0922.shim@samsung.com> Cc: m.szyprowski@samsung.com Cc: t.fujak@samsung.com Cc: kyungmin.park@samsung.com, Cc: David Brownell <david-b@pacbell.net> Cc: Daniel Ribeiro <drwyrm@gmail.com> Cc: arve@android.com Cc: Barry Song <21cnbao@gmail.com>
2009-08-13 19:21:38 +08:00
extern void set_irq_nested_thread(unsigned int irq, int nest);
void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set);
static inline void irq_set_status_flags(unsigned int irq, unsigned long set)
{
irq_modify_status(irq, 0, set);
}
static inline void irq_clear_status_flags(unsigned int irq, unsigned long clr)
{
irq_modify_status(irq, clr, 0);
}
static inline void set_irq_noprobe(unsigned int irq)
{
irq_modify_status(irq, 0, IRQ_NOPROBE);
}
static inline void set_irq_probe(unsigned int irq)
{
irq_modify_status(irq, IRQ_NOPROBE, 0);
}
[PATCH] genirq: irq: add a dynamic irq creation API With the msi support comes a new concept in irq handling, irqs that are created dynamically at run time. Currently the msi code allocates irqs backwards. First it allocates a platform dependent routing value for an interrupt the ``vector'' and then it figures out from the vector which irq you are on. This msi backwards allocator suffers from two basic problems. The allocator suffers because it is trying to do something that is architecture specific in a generic way making it brittle, inflexible, and tied to tightly to the architecture implementation. The alloctor also suffers from it's very backwards nature as it has tied things together that should have no dependencies. To solve the basic dynamic irq allocation problem two new architecture specific functions are added: create_irq and destroy_irq. create_irq takes no input and returns an unused irq number, that won't be reused until it is returned to the free poll with destroy_irq. The irq then can be used for any purpose although the only initial consumer is the msi code. destroy_irq takes an irq number allocated with create_irq and returns it to the free pool. Making this functionality per architecture increases the simplicity of the irq allocation code and increases it's flexibility. dynamic_irq_init() and dynamic_irq_cleanup() are added to automate the irq_desc initializtion that should happen for dynamic irqs. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rajesh Shah <rajesh.shah@intel.com> Cc: Andi Kleen <ak@muc.de> Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 17:16:37 +08:00
/* Handle dynamic irq creation and destruction */
extern unsigned int create_irq_nr(unsigned int irq_want, int node);
[PATCH] genirq: irq: add a dynamic irq creation API With the msi support comes a new concept in irq handling, irqs that are created dynamically at run time. Currently the msi code allocates irqs backwards. First it allocates a platform dependent routing value for an interrupt the ``vector'' and then it figures out from the vector which irq you are on. This msi backwards allocator suffers from two basic problems. The allocator suffers because it is trying to do something that is architecture specific in a generic way making it brittle, inflexible, and tied to tightly to the architecture implementation. The alloctor also suffers from it's very backwards nature as it has tied things together that should have no dependencies. To solve the basic dynamic irq allocation problem two new architecture specific functions are added: create_irq and destroy_irq. create_irq takes no input and returns an unused irq number, that won't be reused until it is returned to the free poll with destroy_irq. The irq then can be used for any purpose although the only initial consumer is the msi code. destroy_irq takes an irq number allocated with create_irq and returns it to the free pool. Making this functionality per architecture increases the simplicity of the irq allocation code and increases it's flexibility. dynamic_irq_init() and dynamic_irq_cleanup() are added to automate the irq_desc initializtion that should happen for dynamic irqs. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rajesh Shah <rajesh.shah@intel.com> Cc: Andi Kleen <ak@muc.de> Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 17:16:37 +08:00
extern int create_irq(void);
extern void destroy_irq(unsigned int irq);
/* Dynamic irq helper functions */
extern void dynamic_irq_init(unsigned int irq);
x86: Avoid race condition in pci_enable_msix() Keep chip_data in create_irq_nr and destroy_irq. When two drivers are setting up MSI-X at the same time via pci_enable_msix() there is a race. See this dmesg excerpt: [ 85.170610] ixgbe 0000:02:00.1: irq 97 for MSI/MSI-X [ 85.170611] alloc irq_desc for 99 on node -1 [ 85.170613] igb 0000:08:00.1: irq 98 for MSI/MSI-X [ 85.170614] alloc kstat_irqs on node -1 [ 85.170616] alloc irq_2_iommu on node -1 [ 85.170617] alloc irq_desc for 100 on node -1 [ 85.170619] alloc kstat_irqs on node -1 [ 85.170621] alloc irq_2_iommu on node -1 [ 85.170625] ixgbe 0000:02:00.1: irq 99 for MSI/MSI-X [ 85.170626] alloc irq_desc for 101 on node -1 [ 85.170628] igb 0000:08:00.1: irq 100 for MSI/MSI-X [ 85.170630] alloc kstat_irqs on node -1 [ 85.170631] alloc irq_2_iommu on node -1 [ 85.170635] alloc irq_desc for 102 on node -1 [ 85.170636] alloc kstat_irqs on node -1 [ 85.170639] alloc irq_2_iommu on node -1 [ 85.170646] BUG: unable to handle kernel NULL pointer dereference at 0000000000000088 As you can see igb and ixgbe are both alternating on create_irq_nr() via pci_enable_msix() in their probe function. ixgbe: While looping through irq_desc_ptrs[] via create_irq_nr() ixgbe choses irq_desc_ptrs[102] and exits the loop, drops vector_lock and calls dynamic_irq_init. Then it sets irq_desc_ptrs[102]->chip_data = NULL via dynamic_irq_init(). igb: Grabs the vector_lock now and starts looping over irq_desc_ptrs[] via create_irq_nr(). It gets to irq_desc_ptrs[102] and does this: cfg_new = irq_desc_ptrs[102]->chip_data; if (cfg_new->vector != 0) continue; This hits the NULL deref. Another possible race exists via pci_disable_msix() in a driver or in the number of error paths that call free_msi_irqs(): destroy_irq() dynamic_irq_cleanup() which sets desc->chip_data = NULL ...race window... desc->chip_data = cfg; Remove the save and restore code for cfg in create_irq_nr() and destroy_irq() and take the desc->lock when checking the irq_cfg. Reported-and-analyzed-by: Brandon Philips <bphilips@suse.de> Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <1265793639-15071-3-git-send-email-yinghai@kernel.org> Signed-off-by: Brandon Phililps <bphilips@suse.de> Cc: stable@kernel.org Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-10 17:20:06 +08:00
void dynamic_irq_init_keep_chip_data(unsigned int irq);
[PATCH] genirq: irq: add a dynamic irq creation API With the msi support comes a new concept in irq handling, irqs that are created dynamically at run time. Currently the msi code allocates irqs backwards. First it allocates a platform dependent routing value for an interrupt the ``vector'' and then it figures out from the vector which irq you are on. This msi backwards allocator suffers from two basic problems. The allocator suffers because it is trying to do something that is architecture specific in a generic way making it brittle, inflexible, and tied to tightly to the architecture implementation. The alloctor also suffers from it's very backwards nature as it has tied things together that should have no dependencies. To solve the basic dynamic irq allocation problem two new architecture specific functions are added: create_irq and destroy_irq. create_irq takes no input and returns an unused irq number, that won't be reused until it is returned to the free poll with destroy_irq. The irq then can be used for any purpose although the only initial consumer is the msi code. destroy_irq takes an irq number allocated with create_irq and returns it to the free pool. Making this functionality per architecture increases the simplicity of the irq allocation code and increases it's flexibility. dynamic_irq_init() and dynamic_irq_cleanup() are added to automate the irq_desc initializtion that should happen for dynamic irqs. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rajesh Shah <rajesh.shah@intel.com> Cc: Andi Kleen <ak@muc.de> Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 17:16:37 +08:00
extern void dynamic_irq_cleanup(unsigned int irq);
x86: Avoid race condition in pci_enable_msix() Keep chip_data in create_irq_nr and destroy_irq. When two drivers are setting up MSI-X at the same time via pci_enable_msix() there is a race. See this dmesg excerpt: [ 85.170610] ixgbe 0000:02:00.1: irq 97 for MSI/MSI-X [ 85.170611] alloc irq_desc for 99 on node -1 [ 85.170613] igb 0000:08:00.1: irq 98 for MSI/MSI-X [ 85.170614] alloc kstat_irqs on node -1 [ 85.170616] alloc irq_2_iommu on node -1 [ 85.170617] alloc irq_desc for 100 on node -1 [ 85.170619] alloc kstat_irqs on node -1 [ 85.170621] alloc irq_2_iommu on node -1 [ 85.170625] ixgbe 0000:02:00.1: irq 99 for MSI/MSI-X [ 85.170626] alloc irq_desc for 101 on node -1 [ 85.170628] igb 0000:08:00.1: irq 100 for MSI/MSI-X [ 85.170630] alloc kstat_irqs on node -1 [ 85.170631] alloc irq_2_iommu on node -1 [ 85.170635] alloc irq_desc for 102 on node -1 [ 85.170636] alloc kstat_irqs on node -1 [ 85.170639] alloc irq_2_iommu on node -1 [ 85.170646] BUG: unable to handle kernel NULL pointer dereference at 0000000000000088 As you can see igb and ixgbe are both alternating on create_irq_nr() via pci_enable_msix() in their probe function. ixgbe: While looping through irq_desc_ptrs[] via create_irq_nr() ixgbe choses irq_desc_ptrs[102] and exits the loop, drops vector_lock and calls dynamic_irq_init. Then it sets irq_desc_ptrs[102]->chip_data = NULL via dynamic_irq_init(). igb: Grabs the vector_lock now and starts looping over irq_desc_ptrs[] via create_irq_nr(). It gets to irq_desc_ptrs[102] and does this: cfg_new = irq_desc_ptrs[102]->chip_data; if (cfg_new->vector != 0) continue; This hits the NULL deref. Another possible race exists via pci_disable_msix() in a driver or in the number of error paths that call free_msi_irqs(): destroy_irq() dynamic_irq_cleanup() which sets desc->chip_data = NULL ...race window... desc->chip_data = cfg; Remove the save and restore code for cfg in create_irq_nr() and destroy_irq() and take the desc->lock when checking the irq_cfg. Reported-and-analyzed-by: Brandon Philips <bphilips@suse.de> Signed-off-by: Yinghai Lu <yinghai@kernel.org> LKML-Reference: <1265793639-15071-3-git-send-email-yinghai@kernel.org> Signed-off-by: Brandon Phililps <bphilips@suse.de> Cc: stable@kernel.org Signed-off-by: H. Peter Anvin <hpa@zytor.com>
2010-02-10 17:20:06 +08:00
void dynamic_irq_cleanup_keep_chip_data(unsigned int irq);
[PATCH] genirq: irq: add a dynamic irq creation API With the msi support comes a new concept in irq handling, irqs that are created dynamically at run time. Currently the msi code allocates irqs backwards. First it allocates a platform dependent routing value for an interrupt the ``vector'' and then it figures out from the vector which irq you are on. This msi backwards allocator suffers from two basic problems. The allocator suffers because it is trying to do something that is architecture specific in a generic way making it brittle, inflexible, and tied to tightly to the architecture implementation. The alloctor also suffers from it's very backwards nature as it has tied things together that should have no dependencies. To solve the basic dynamic irq allocation problem two new architecture specific functions are added: create_irq and destroy_irq. create_irq takes no input and returns an unused irq number, that won't be reused until it is returned to the free poll with destroy_irq. The irq then can be used for any purpose although the only initial consumer is the msi code. destroy_irq takes an irq number allocated with create_irq and returns it to the free pool. Making this functionality per architecture increases the simplicity of the irq allocation code and increases it's flexibility. dynamic_irq_init() and dynamic_irq_cleanup() are added to automate the irq_desc initializtion that should happen for dynamic irqs. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Rajesh Shah <rajesh.shah@intel.com> Cc: Andi Kleen <ak@muc.de> Cc: "Protasevich, Natalie" <Natalie.Protasevich@UNISYS.com> Cc: "Luck, Tony" <tony.luck@intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-04 17:16:37 +08:00
/* Set/get chip/data for an IRQ: */
extern int set_irq_chip(unsigned int irq, struct irq_chip *chip);
extern int set_irq_data(unsigned int irq, void *data);
extern int set_irq_chip_data(unsigned int irq, void *data);
extern int set_irq_type(unsigned int irq, unsigned int type);
extern int set_irq_msi(unsigned int irq, struct msi_desc *entry);
#define get_irq_chip(irq) (irq_to_desc(irq)->irq_data.chip)
#define get_irq_chip_data(irq) (irq_to_desc(irq)->irq_data.chip_data)
#define get_irq_data(irq) (irq_to_desc(irq)->irq_data.handler_data)
#define get_irq_msi(irq) (irq_to_desc(irq)->irq_data.msi_desc)
#endif /* CONFIG_GENERIC_HARDIRQS */
#endif /* !CONFIG_S390 */
#endif /* _LINUX_IRQ_H */