kernel-ark/include/linux/dmar.h

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Intel IOMMU: DMAR detection and parsing logic This patch supports the upcomming Intel IOMMU hardware a.k.a. Intel(R) Virtualization Technology for Directed I/O Architecture and the hardware spec for the same can be found here http://www.intel.com/technology/virtualization/index.htm FAQ! (questions from akpm, answers from ak) > So... what's all this code for? > > I assume that the intent here is to speed things up under Xen, etc? Yes in some cases, but not this code. That would be the Xen version of this code that could potentially assign whole devices to guests. I expect this to be only useful in some special cases though because most hardware is not virtualizable and you typically want an own instance for each guest. Ok at some point KVM might implement this too; i likely would use this code for this. > Do we > have any benchmark results to help us to decide whether a merge would be > justified? The main advantage for doing it in the normal kernel is not performance, but more safety. Broken devices won't be able to corrupt memory by doing random DMA. Unfortunately that doesn't work for graphics yet, for that need user space interfaces for the X server are needed. There are some potential performance benefits too: - When you have a device that cannot address the complete address range an IOMMU can remap its memory instead of bounce buffering. Remapping is likely cheaper than copying. - The IOMMU can merge sg lists into a single virtual block. This could potentially speed up SG IO when the device is slow walking SG lists. [I long ago benchmarked 5% on some block benchmark with an old MPT Fusion; but it probably depends a lot on the HBA] And you get better driver debugging because unexpected memory accesses from the devices will cause a trappable event. > > Does it slow anything down? It adds more overhead to each IO so yes. This patch: Add support for early detection and parsing of DMAR's (DMA Remapping) reported to OS via ACPI tables. DMA remapping(DMAR) devices support enables independent address translations for Direct Memory Access(DMA) from Devices. These DMA remapping devices are reported via ACPI tables and includes pci device scope covered by these DMA remapping device. For detailed info on the specification of "Intel(R) Virtualization Technology for Directed I/O Architecture" please see http://www.intel.com/technology/virtualization/index.htm Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Andi Kleen <ak@suse.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Muli Ben-Yehuda <muli@il.ibm.com> Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Ashok Raj <ashok.raj@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Christoph Lameter <clameter@sgi.com> Cc: Greg KH <greg@kroah.com> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-21 23:41:41 +00:00
/*
* Copyright (c) 2006, Intel Corporation.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc., 59 Temple
* Place - Suite 330, Boston, MA 02111-1307 USA.
*
* Copyright (C) Ashok Raj <ashok.raj@intel.com>
* Copyright (C) Shaohua Li <shaohua.li@intel.com>
*/
#ifndef __DMAR_H__
#define __DMAR_H__
#include <linux/acpi.h>
#include <linux/types.h>
#include <linux/msi.h>
#include <linux/irqreturn.h>
Intel IOMMU: DMAR detection and parsing logic This patch supports the upcomming Intel IOMMU hardware a.k.a. Intel(R) Virtualization Technology for Directed I/O Architecture and the hardware spec for the same can be found here http://www.intel.com/technology/virtualization/index.htm FAQ! (questions from akpm, answers from ak) > So... what's all this code for? > > I assume that the intent here is to speed things up under Xen, etc? Yes in some cases, but not this code. That would be the Xen version of this code that could potentially assign whole devices to guests. I expect this to be only useful in some special cases though because most hardware is not virtualizable and you typically want an own instance for each guest. Ok at some point KVM might implement this too; i likely would use this code for this. > Do we > have any benchmark results to help us to decide whether a merge would be > justified? The main advantage for doing it in the normal kernel is not performance, but more safety. Broken devices won't be able to corrupt memory by doing random DMA. Unfortunately that doesn't work for graphics yet, for that need user space interfaces for the X server are needed. There are some potential performance benefits too: - When you have a device that cannot address the complete address range an IOMMU can remap its memory instead of bounce buffering. Remapping is likely cheaper than copying. - The IOMMU can merge sg lists into a single virtual block. This could potentially speed up SG IO when the device is slow walking SG lists. [I long ago benchmarked 5% on some block benchmark with an old MPT Fusion; but it probably depends a lot on the HBA] And you get better driver debugging because unexpected memory accesses from the devices will cause a trappable event. > > Does it slow anything down? It adds more overhead to each IO so yes. This patch: Add support for early detection and parsing of DMAR's (DMA Remapping) reported to OS via ACPI tables. DMA remapping(DMAR) devices support enables independent address translations for Direct Memory Access(DMA) from Devices. These DMA remapping devices are reported via ACPI tables and includes pci device scope covered by these DMA remapping device. For detailed info on the specification of "Intel(R) Virtualization Technology for Directed I/O Architecture" please see http://www.intel.com/technology/virtualization/index.htm Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Andi Kleen <ak@suse.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Muli Ben-Yehuda <muli@il.ibm.com> Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Ashok Raj <ashok.raj@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Christoph Lameter <clameter@sgi.com> Cc: Greg KH <greg@kroah.com> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-21 23:41:41 +00:00
struct acpi_dmar_header;
x86, x2apic: Enable the bios request for x2apic optout On the platforms which are x2apic and interrupt-remapping capable, Linux kernel is enabling x2apic even if the BIOS doesn't. This is to take advantage of the features that x2apic brings in. Some of the OEM platforms are running into issues because of this, as their bios is not x2apic aware. For example, this was resulting in interrupt migration issues on one of the platforms. Also if the BIOS SMI handling uses APIC interface to send SMI's, then the BIOS need to be aware of x2apic mode that OS has enabled. On some of these platforms, BIOS doesn't have a HW mechanism to turnoff the x2apic feature to prevent OS from enabling it. To resolve this mess, recent changes to the VT-d2 specification: http://download.intel.com/technology/computing/vptech/Intel(r)_VT_for_Direct_IO.pdf includes a mechanism that provides BIOS a way to request system software to opt out of enabling x2apic mode. Look at the x2apic optout flag in the DMAR tables before enabling the x2apic mode in the platform. Also print a warning that we have disabled x2apic based on the BIOS request. Kernel boot parameter "intremap=no_x2apic_optout" can be used to override the BIOS x2apic optout request. Signed-off-by: Youquan Song <youquan.song@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: yinghai@kernel.org Cc: joerg.roedel@amd.com Cc: tony.luck@intel.com Cc: dwmw2@infradead.org Link: http://lkml.kernel.org/r/20110824001456.171766616@sbsiddha-desk.sc.intel.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-24 00:05:18 +00:00
/* DMAR Flags */
#define DMAR_INTR_REMAP 0x1
#define DMAR_X2APIC_OPT_OUT 0x2
struct intel_iommu;
#ifdef CONFIG_DMAR_TABLE
x86, x2apic: Enable the bios request for x2apic optout On the platforms which are x2apic and interrupt-remapping capable, Linux kernel is enabling x2apic even if the BIOS doesn't. This is to take advantage of the features that x2apic brings in. Some of the OEM platforms are running into issues because of this, as their bios is not x2apic aware. For example, this was resulting in interrupt migration issues on one of the platforms. Also if the BIOS SMI handling uses APIC interface to send SMI's, then the BIOS need to be aware of x2apic mode that OS has enabled. On some of these platforms, BIOS doesn't have a HW mechanism to turnoff the x2apic feature to prevent OS from enabling it. To resolve this mess, recent changes to the VT-d2 specification: http://download.intel.com/technology/computing/vptech/Intel(r)_VT_for_Direct_IO.pdf includes a mechanism that provides BIOS a way to request system software to opt out of enabling x2apic mode. Look at the x2apic optout flag in the DMAR tables before enabling the x2apic mode in the platform. Also print a warning that we have disabled x2apic based on the BIOS request. Kernel boot parameter "intremap=no_x2apic_optout" can be used to override the BIOS x2apic optout request. Signed-off-by: Youquan Song <youquan.song@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: yinghai@kernel.org Cc: joerg.roedel@amd.com Cc: tony.luck@intel.com Cc: dwmw2@infradead.org Link: http://lkml.kernel.org/r/20110824001456.171766616@sbsiddha-desk.sc.intel.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-24 00:05:18 +00:00
extern struct acpi_table_header *dmar_tbl;
struct dmar_drhd_unit {
struct list_head list; /* list of drhd units */
struct acpi_dmar_header *hdr; /* ACPI header */
u64 reg_base_addr; /* register base address*/
struct pci_dev **devices; /* target device array */
int devices_cnt; /* target device count */
u16 segment; /* PCI domain */
u8 ignored:1; /* ignore drhd */
u8 include_all:1;
struct intel_iommu *iommu;
};
extern struct list_head dmar_drhd_units;
#define for_each_drhd_unit(drhd) \
list_for_each_entry(drhd, &dmar_drhd_units, list)
#define for_each_active_iommu(i, drhd) \
list_for_each_entry(drhd, &dmar_drhd_units, list) \
if (i=drhd->iommu, drhd->ignored) {} else
#define for_each_iommu(i, drhd) \
list_for_each_entry(drhd, &dmar_drhd_units, list) \
if (i=drhd->iommu, 0) {} else
extern int dmar_table_init(void);
extern int dmar_dev_scope_init(void);
/* Intel IOMMU detection */
extern int detect_intel_iommu(void);
extern int enable_drhd_fault_handling(void);
extern int parse_ioapics_under_ir(void);
extern int alloc_iommu(struct dmar_drhd_unit *);
#else
static inline int detect_intel_iommu(void)
{
return -ENODEV;
}
static inline int dmar_table_init(void)
{
return -ENODEV;
}
static inline int enable_drhd_fault_handling(void)
{
return -1;
}
#endif /* !CONFIG_DMAR_TABLE */
struct irte {
union {
struct {
__u64 present : 1,
fpd : 1,
dst_mode : 1,
redir_hint : 1,
trigger_mode : 1,
dlvry_mode : 3,
avail : 4,
__reserved_1 : 4,
vector : 8,
__reserved_2 : 8,
dest_id : 32;
};
__u64 low;
};
union {
struct {
__u64 sid : 16,
sq : 2,
svt : 2,
__reserved_3 : 44;
};
__u64 high;
};
};
x86, x2apic: Enable the bios request for x2apic optout On the platforms which are x2apic and interrupt-remapping capable, Linux kernel is enabling x2apic even if the BIOS doesn't. This is to take advantage of the features that x2apic brings in. Some of the OEM platforms are running into issues because of this, as their bios is not x2apic aware. For example, this was resulting in interrupt migration issues on one of the platforms. Also if the BIOS SMI handling uses APIC interface to send SMI's, then the BIOS need to be aware of x2apic mode that OS has enabled. On some of these platforms, BIOS doesn't have a HW mechanism to turnoff the x2apic feature to prevent OS from enabling it. To resolve this mess, recent changes to the VT-d2 specification: http://download.intel.com/technology/computing/vptech/Intel(r)_VT_for_Direct_IO.pdf includes a mechanism that provides BIOS a way to request system software to opt out of enabling x2apic mode. Look at the x2apic optout flag in the DMAR tables before enabling the x2apic mode in the platform. Also print a warning that we have disabled x2apic based on the BIOS request. Kernel boot parameter "intremap=no_x2apic_optout" can be used to override the BIOS x2apic optout request. Signed-off-by: Youquan Song <youquan.song@intel.com> Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com> Cc: yinghai@kernel.org Cc: joerg.roedel@amd.com Cc: tony.luck@intel.com Cc: dwmw2@infradead.org Link: http://lkml.kernel.org/r/20110824001456.171766616@sbsiddha-desk.sc.intel.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-08-24 00:05:18 +00:00
enum {
IRQ_REMAP_XAPIC_MODE,
IRQ_REMAP_X2APIC_MODE,
};
/* Can't use the common MSI interrupt functions
* since DMAR is not a pci device
*/
struct irq_data;
extern void dmar_msi_unmask(struct irq_data *data);
extern void dmar_msi_mask(struct irq_data *data);
extern void dmar_msi_read(int irq, struct msi_msg *msg);
extern void dmar_msi_write(int irq, struct msi_msg *msg);
extern int dmar_set_interrupt(struct intel_iommu *iommu);
extern irqreturn_t dmar_fault(int irq, void *dev_id);
extern int arch_setup_dmar_msi(unsigned int irq);
#ifdef CONFIG_INTEL_IOMMU
extern int iommu_detected, no_iommu;
Intel IOMMU: DMAR detection and parsing logic This patch supports the upcomming Intel IOMMU hardware a.k.a. Intel(R) Virtualization Technology for Directed I/O Architecture and the hardware spec for the same can be found here http://www.intel.com/technology/virtualization/index.htm FAQ! (questions from akpm, answers from ak) > So... what's all this code for? > > I assume that the intent here is to speed things up under Xen, etc? Yes in some cases, but not this code. That would be the Xen version of this code that could potentially assign whole devices to guests. I expect this to be only useful in some special cases though because most hardware is not virtualizable and you typically want an own instance for each guest. Ok at some point KVM might implement this too; i likely would use this code for this. > Do we > have any benchmark results to help us to decide whether a merge would be > justified? The main advantage for doing it in the normal kernel is not performance, but more safety. Broken devices won't be able to corrupt memory by doing random DMA. Unfortunately that doesn't work for graphics yet, for that need user space interfaces for the X server are needed. There are some potential performance benefits too: - When you have a device that cannot address the complete address range an IOMMU can remap its memory instead of bounce buffering. Remapping is likely cheaper than copying. - The IOMMU can merge sg lists into a single virtual block. This could potentially speed up SG IO when the device is slow walking SG lists. [I long ago benchmarked 5% on some block benchmark with an old MPT Fusion; but it probably depends a lot on the HBA] And you get better driver debugging because unexpected memory accesses from the devices will cause a trappable event. > > Does it slow anything down? It adds more overhead to each IO so yes. This patch: Add support for early detection and parsing of DMAR's (DMA Remapping) reported to OS via ACPI tables. DMA remapping(DMAR) devices support enables independent address translations for Direct Memory Access(DMA) from Devices. These DMA remapping devices are reported via ACPI tables and includes pci device scope covered by these DMA remapping device. For detailed info on the specification of "Intel(R) Virtualization Technology for Directed I/O Architecture" please see http://www.intel.com/technology/virtualization/index.htm Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Andi Kleen <ak@suse.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Muli Ben-Yehuda <muli@il.ibm.com> Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Ashok Raj <ashok.raj@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Christoph Lameter <clameter@sgi.com> Cc: Greg KH <greg@kroah.com> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-21 23:41:41 +00:00
extern struct list_head dmar_rmrr_units;
struct dmar_rmrr_unit {
struct list_head list; /* list of rmrr units */
struct acpi_dmar_header *hdr; /* ACPI header */
Intel IOMMU: DMAR detection and parsing logic This patch supports the upcomming Intel IOMMU hardware a.k.a. Intel(R) Virtualization Technology for Directed I/O Architecture and the hardware spec for the same can be found here http://www.intel.com/technology/virtualization/index.htm FAQ! (questions from akpm, answers from ak) > So... what's all this code for? > > I assume that the intent here is to speed things up under Xen, etc? Yes in some cases, but not this code. That would be the Xen version of this code that could potentially assign whole devices to guests. I expect this to be only useful in some special cases though because most hardware is not virtualizable and you typically want an own instance for each guest. Ok at some point KVM might implement this too; i likely would use this code for this. > Do we > have any benchmark results to help us to decide whether a merge would be > justified? The main advantage for doing it in the normal kernel is not performance, but more safety. Broken devices won't be able to corrupt memory by doing random DMA. Unfortunately that doesn't work for graphics yet, for that need user space interfaces for the X server are needed. There are some potential performance benefits too: - When you have a device that cannot address the complete address range an IOMMU can remap its memory instead of bounce buffering. Remapping is likely cheaper than copying. - The IOMMU can merge sg lists into a single virtual block. This could potentially speed up SG IO when the device is slow walking SG lists. [I long ago benchmarked 5% on some block benchmark with an old MPT Fusion; but it probably depends a lot on the HBA] And you get better driver debugging because unexpected memory accesses from the devices will cause a trappable event. > > Does it slow anything down? It adds more overhead to each IO so yes. This patch: Add support for early detection and parsing of DMAR's (DMA Remapping) reported to OS via ACPI tables. DMA remapping(DMAR) devices support enables independent address translations for Direct Memory Access(DMA) from Devices. These DMA remapping devices are reported via ACPI tables and includes pci device scope covered by these DMA remapping device. For detailed info on the specification of "Intel(R) Virtualization Technology for Directed I/O Architecture" please see http://www.intel.com/technology/virtualization/index.htm Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Andi Kleen <ak@suse.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Muli Ben-Yehuda <muli@il.ibm.com> Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Ashok Raj <ashok.raj@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Christoph Lameter <clameter@sgi.com> Cc: Greg KH <greg@kroah.com> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-21 23:41:41 +00:00
u64 base_address; /* reserved base address*/
u64 end_address; /* reserved end address */
struct pci_dev **devices; /* target devices */
int devices_cnt; /* target device count */
};
#define for_each_rmrr_units(rmrr) \
list_for_each_entry(rmrr, &dmar_rmrr_units, list)
struct dmar_atsr_unit {
struct list_head list; /* list of ATSR units */
struct acpi_dmar_header *hdr; /* ACPI header */
struct pci_dev **devices; /* target devices */
int devices_cnt; /* target device count */
u8 include_all:1; /* include all ports */
};
int dmar_parse_rmrr_atsr_dev(void);
extern int dmar_parse_one_rmrr(struct acpi_dmar_header *header);
extern int dmar_parse_one_atsr(struct acpi_dmar_header *header);
extern int dmar_parse_dev_scope(void *start, void *end, int *cnt,
struct pci_dev ***devices, u16 segment);
extern int intel_iommu_init(void);
#else /* !CONFIG_INTEL_IOMMU: */
static inline int intel_iommu_init(void) { return -ENODEV; }
static inline int dmar_parse_one_rmrr(struct acpi_dmar_header *header)
{
return 0;
}
static inline int dmar_parse_one_atsr(struct acpi_dmar_header *header)
{
return 0;
}
static inline int dmar_parse_rmrr_atsr_dev(void)
{
return 0;
}
#endif /* CONFIG_INTEL_IOMMU */
Intel IOMMU: DMAR detection and parsing logic This patch supports the upcomming Intel IOMMU hardware a.k.a. Intel(R) Virtualization Technology for Directed I/O Architecture and the hardware spec for the same can be found here http://www.intel.com/technology/virtualization/index.htm FAQ! (questions from akpm, answers from ak) > So... what's all this code for? > > I assume that the intent here is to speed things up under Xen, etc? Yes in some cases, but not this code. That would be the Xen version of this code that could potentially assign whole devices to guests. I expect this to be only useful in some special cases though because most hardware is not virtualizable and you typically want an own instance for each guest. Ok at some point KVM might implement this too; i likely would use this code for this. > Do we > have any benchmark results to help us to decide whether a merge would be > justified? The main advantage for doing it in the normal kernel is not performance, but more safety. Broken devices won't be able to corrupt memory by doing random DMA. Unfortunately that doesn't work for graphics yet, for that need user space interfaces for the X server are needed. There are some potential performance benefits too: - When you have a device that cannot address the complete address range an IOMMU can remap its memory instead of bounce buffering. Remapping is likely cheaper than copying. - The IOMMU can merge sg lists into a single virtual block. This could potentially speed up SG IO when the device is slow walking SG lists. [I long ago benchmarked 5% on some block benchmark with an old MPT Fusion; but it probably depends a lot on the HBA] And you get better driver debugging because unexpected memory accesses from the devices will cause a trappable event. > > Does it slow anything down? It adds more overhead to each IO so yes. This patch: Add support for early detection and parsing of DMAR's (DMA Remapping) reported to OS via ACPI tables. DMA remapping(DMAR) devices support enables independent address translations for Direct Memory Access(DMA) from Devices. These DMA remapping devices are reported via ACPI tables and includes pci device scope covered by these DMA remapping device. For detailed info on the specification of "Intel(R) Virtualization Technology for Directed I/O Architecture" please see http://www.intel.com/technology/virtualization/index.htm Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: Andi Kleen <ak@suse.de> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Muli Ben-Yehuda <muli@il.ibm.com> Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com> Cc: Arjan van de Ven <arjan@infradead.org> Cc: Ashok Raj <ashok.raj@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Christoph Lameter <clameter@sgi.com> Cc: Greg KH <greg@kroah.com> Cc: Len Brown <lenb@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-21 23:41:41 +00:00
#endif /* __DMAR_H__ */