linux/arch/powerpc/kvm/book3s_xive.h

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/*
* Copyright 2017 Benjamin Herrenschmidt, IBM Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, version 2, as
* published by the Free Software Foundation.
*/
#ifndef _KVM_PPC_BOOK3S_XIVE_H
#define _KVM_PPC_BOOK3S_XIVE_H
#ifdef CONFIG_KVM_XICS
#include "book3s_xics.h"
/*
* The XIVE Interrupt source numbers are within the range 0 to
* KVMPPC_XICS_NR_IRQS.
*/
#define KVMPPC_XIVE_FIRST_IRQ 0
#define KVMPPC_XIVE_NR_IRQS KVMPPC_XICS_NR_IRQS
/*
* State for one guest irq source.
*
* For each guest source we allocate a HW interrupt in the XIVE
* which we use for all SW triggers. It will be unused for
* pass-through but it's easier to keep around as the same
* guest interrupt can alternatively be emulated or pass-through
* if a physical device is hot unplugged and replaced with an
* emulated one.
*
* This state structure is very similar to the XICS one with
* additional XIVE specific tracking.
*/
struct kvmppc_xive_irq_state {
bool valid; /* Interrupt entry is valid */
u32 number; /* Guest IRQ number */
u32 ipi_number; /* XIVE IPI HW number */
struct xive_irq_data ipi_data; /* XIVE IPI associated data */
u32 pt_number; /* XIVE Pass-through number if any */
struct xive_irq_data *pt_data; /* XIVE Pass-through associated data */
/* Targetting as set by guest */
u8 guest_priority; /* Guest set priority */
u8 saved_priority; /* Saved priority when masking */
/* Actual targetting */
u32 act_server; /* Actual server */
u8 act_priority; /* Actual priority */
/* Various state bits */
bool in_eoi; /* Synchronize with H_EOI */
bool old_p; /* P bit state when masking */
bool old_q; /* Q bit state when masking */
bool lsi; /* level-sensitive interrupt */
bool asserted; /* Only for emulated LSI: current state */
/* Saved for migration state */
bool in_queue;
bool saved_p;
bool saved_q;
u8 saved_scan_prio;
/* Xive native */
u32 eisn; /* Guest Effective IRQ number */
};
/* Select the "right" interrupt (IPI vs. passthrough) */
static inline void kvmppc_xive_select_irq(struct kvmppc_xive_irq_state *state,
u32 *out_hw_irq,
struct xive_irq_data **out_xd)
{
if (state->pt_number) {
if (out_hw_irq)
*out_hw_irq = state->pt_number;
if (out_xd)
*out_xd = state->pt_data;
} else {
if (out_hw_irq)
*out_hw_irq = state->ipi_number;
if (out_xd)
*out_xd = &state->ipi_data;
}
}
/*
* This corresponds to an "ICS" in XICS terminology, we use it
* as a mean to break up source information into multiple structures.
*/
struct kvmppc_xive_src_block {
arch_spinlock_t lock;
u16 id;
struct kvmppc_xive_irq_state irq_state[KVMPPC_XICS_IRQ_PER_ICS];
};
KVM: PPC: Book3S HV: XIVE: Add passthrough support The KVM XICS-over-XIVE device and the proposed KVM XIVE native device implement an IRQ space for the guest using the generic IPI interrupts of the XIVE IC controller. These interrupts are allocated at the OPAL level and "mapped" into the guest IRQ number space in the range 0-0x1FFF. Interrupt management is performed in the XIVE way: using loads and stores on the addresses of the XIVE IPI interrupt ESB pages. Both KVM devices share the same internal structure caching information on the interrupts, among which the xive_irq_data struct containing the addresses of the IPI ESB pages and an extra one in case of pass-through. The later contains the addresses of the ESB pages of the underlying HW controller interrupts, PHB4 in all cases for now. A guest, when running in the XICS legacy interrupt mode, lets the KVM XICS-over-XIVE device "handle" interrupt management, that is to perform the loads and stores on the addresses of the ESB pages of the guest interrupts. However, when running in XIVE native exploitation mode, the KVM XIVE native device exposes the interrupt ESB pages to the guest and lets the guest perform directly the loads and stores. The VMA exposing the ESB pages make use of a custom VM fault handler which role is to populate the VMA with appropriate pages. When a fault occurs, the guest IRQ number is deduced from the offset, and the ESB pages of associated XIVE IPI interrupt are inserted in the VMA (using the internal structure caching information on the interrupts). Supporting device passthrough in the guest running in XIVE native exploitation mode adds some extra refinements because the ESB pages of a different HW controller (PHB4) need to be exposed to the guest along with the initial IPI ESB pages of the XIVE IC controller. But the overall mechanic is the same. When the device HW irqs are mapped into or unmapped from the guest IRQ number space, the passthru_irq helpers, kvmppc_xive_set_mapped() and kvmppc_xive_clr_mapped(), are called to record or clear the passthrough interrupt information and to perform the switch. The approach taken by this patch is to clear the ESB pages of the guest IRQ number being mapped and let the VM fault handler repopulate. The handler will insert the ESB page corresponding to the HW interrupt of the device being passed-through or the initial IPI ESB page if the device is being removed. Signed-off-by: Cédric Le Goater <clg@kaod.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-04-18 18:39:39 +08:00
struct kvmppc_xive;
struct kvmppc_xive_ops {
int (*reset_mapped)(struct kvm *kvm, unsigned long guest_irq);
};
struct kvmppc_xive {
struct kvm *kvm;
struct kvm_device *dev;
struct dentry *dentry;
/* VP block associated with the VM */
u32 vp_base;
/* Blocks of sources */
struct kvmppc_xive_src_block *src_blocks[KVMPPC_XICS_MAX_ICS_ID + 1];
u32 max_sbid;
/*
* For state save, we lazily scan the queues on the first interrupt
* being migrated. We don't have a clean way to reset that flags
* so we keep track of the number of valid sources and how many of
* them were migrated so we can reset when all of them have been
* processed.
*/
u32 src_count;
u32 saved_src_count;
/*
* Some irqs are delayed on restore until the source is created,
* keep track here of how many of them
*/
u32 delayed_irqs;
/* Which queues (priorities) are in use by the guest */
u8 qmap;
/* Queue orders */
u32 q_order;
u32 q_page_order;
/* Flags */
u8 single_escalation;
KVM: PPC: Book3S HV: XIVE: Add passthrough support The KVM XICS-over-XIVE device and the proposed KVM XIVE native device implement an IRQ space for the guest using the generic IPI interrupts of the XIVE IC controller. These interrupts are allocated at the OPAL level and "mapped" into the guest IRQ number space in the range 0-0x1FFF. Interrupt management is performed in the XIVE way: using loads and stores on the addresses of the XIVE IPI interrupt ESB pages. Both KVM devices share the same internal structure caching information on the interrupts, among which the xive_irq_data struct containing the addresses of the IPI ESB pages and an extra one in case of pass-through. The later contains the addresses of the ESB pages of the underlying HW controller interrupts, PHB4 in all cases for now. A guest, when running in the XICS legacy interrupt mode, lets the KVM XICS-over-XIVE device "handle" interrupt management, that is to perform the loads and stores on the addresses of the ESB pages of the guest interrupts. However, when running in XIVE native exploitation mode, the KVM XIVE native device exposes the interrupt ESB pages to the guest and lets the guest perform directly the loads and stores. The VMA exposing the ESB pages make use of a custom VM fault handler which role is to populate the VMA with appropriate pages. When a fault occurs, the guest IRQ number is deduced from the offset, and the ESB pages of associated XIVE IPI interrupt are inserted in the VMA (using the internal structure caching information on the interrupts). Supporting device passthrough in the guest running in XIVE native exploitation mode adds some extra refinements because the ESB pages of a different HW controller (PHB4) need to be exposed to the guest along with the initial IPI ESB pages of the XIVE IC controller. But the overall mechanic is the same. When the device HW irqs are mapped into or unmapped from the guest IRQ number space, the passthru_irq helpers, kvmppc_xive_set_mapped() and kvmppc_xive_clr_mapped(), are called to record or clear the passthrough interrupt information and to perform the switch. The approach taken by this patch is to clear the ESB pages of the guest IRQ number being mapped and let the VM fault handler repopulate. The handler will insert the ESB page corresponding to the HW interrupt of the device being passed-through or the initial IPI ESB page if the device is being removed. Signed-off-by: Cédric Le Goater <clg@kaod.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2019-04-18 18:39:39 +08:00
struct kvmppc_xive_ops *ops;
struct address_space *mapping;
struct mutex mapping_lock;
};
#define KVMPPC_XIVE_Q_COUNT 8
struct kvmppc_xive_vcpu {
struct kvmppc_xive *xive;
struct kvm_vcpu *vcpu;
bool valid;
/* Server number. This is the HW CPU ID from a guest perspective */
u32 server_num;
/*
* HW VP corresponding to this VCPU. This is the base of the VP
* block plus the server number.
*/
u32 vp_id;
u32 vp_chip_id;
u32 vp_cam;
/* IPI used for sending ... IPIs */
u32 vp_ipi;
struct xive_irq_data vp_ipi_data;
/* Local emulation state */
uint8_t cppr; /* guest CPPR */
uint8_t hw_cppr;/* Hardware CPPR */
uint8_t mfrr;
uint8_t pending;
/* Each VP has 8 queues though we only provision some */
struct xive_q queues[KVMPPC_XIVE_Q_COUNT];
u32 esc_virq[KVMPPC_XIVE_Q_COUNT];
char *esc_virq_names[KVMPPC_XIVE_Q_COUNT];
/* Stash a delayed irq on restore from migration (see set_icp) */
u32 delayed_irq;
/* Stats */
u64 stat_rm_h_xirr;
u64 stat_rm_h_ipoll;
u64 stat_rm_h_cppr;
u64 stat_rm_h_eoi;
u64 stat_rm_h_ipi;
u64 stat_vm_h_xirr;
u64 stat_vm_h_ipoll;
u64 stat_vm_h_cppr;
u64 stat_vm_h_eoi;
u64 stat_vm_h_ipi;
};
static inline struct kvm_vcpu *kvmppc_xive_find_server(struct kvm *kvm, u32 nr)
{
struct kvm_vcpu *vcpu = NULL;
int i;
kvm_for_each_vcpu(i, vcpu, kvm) {
if (vcpu->arch.xive_vcpu && nr == vcpu->arch.xive_vcpu->server_num)
return vcpu;
}
return NULL;
}
static inline struct kvmppc_xive_src_block *kvmppc_xive_find_source(struct kvmppc_xive *xive,
u32 irq, u16 *source)
{
u32 bid = irq >> KVMPPC_XICS_ICS_SHIFT;
u16 src = irq & KVMPPC_XICS_SRC_MASK;
if (source)
*source = src;
if (bid > KVMPPC_XICS_MAX_ICS_ID)
return NULL;
return xive->src_blocks[bid];
}
static inline u32 kvmppc_xive_vp(struct kvmppc_xive *xive, u32 server)
{
return xive->vp_base + kvmppc_pack_vcpu_id(xive->kvm, server);
}
/*
* Mapping between guest priorities and host priorities
* is as follow.
*
* Guest request for 0...6 are honored. Guest request for anything
* higher results in a priority of 6 being applied.
*
* Similar mapping is done for CPPR values
*/
static inline u8 xive_prio_from_guest(u8 prio)
{
if (prio == 0xff || prio < 6)
return prio;
return 6;
}
static inline u8 xive_prio_to_guest(u8 prio)
{
return prio;
}
static inline u32 __xive_read_eq(__be32 *qpage, u32 msk, u32 *idx, u32 *toggle)
{
u32 cur;
if (!qpage)
return 0;
cur = be32_to_cpup(qpage + *idx);
if ((cur >> 31) == *toggle)
return 0;
*idx = (*idx + 1) & msk;
if (*idx == 0)
(*toggle) ^= 1;
return cur & 0x7fffffff;
}
extern unsigned long xive_rm_h_xirr(struct kvm_vcpu *vcpu);
extern unsigned long xive_rm_h_ipoll(struct kvm_vcpu *vcpu, unsigned long server);
extern int xive_rm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server,
unsigned long mfrr);
extern int xive_rm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr);
extern int xive_rm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr);
extern unsigned long (*__xive_vm_h_xirr)(struct kvm_vcpu *vcpu);
extern unsigned long (*__xive_vm_h_ipoll)(struct kvm_vcpu *vcpu, unsigned long server);
extern int (*__xive_vm_h_ipi)(struct kvm_vcpu *vcpu, unsigned long server,
unsigned long mfrr);
extern int (*__xive_vm_h_cppr)(struct kvm_vcpu *vcpu, unsigned long cppr);
extern int (*__xive_vm_h_eoi)(struct kvm_vcpu *vcpu, unsigned long xirr);
/*
* Common Xive routines for XICS-over-XIVE and XIVE native
*/
void kvmppc_xive_disable_vcpu_interrupts(struct kvm_vcpu *vcpu);
int kvmppc_xive_debug_show_queues(struct seq_file *m, struct kvm_vcpu *vcpu);
struct kvmppc_xive_src_block *kvmppc_xive_create_src_block(
struct kvmppc_xive *xive, int irq);
void kvmppc_xive_free_sources(struct kvmppc_xive_src_block *sb);
int kvmppc_xive_select_target(struct kvm *kvm, u32 *server, u8 prio);
int kvmppc_xive_attach_escalation(struct kvm_vcpu *vcpu, u8 prio,
bool single_escalation);
struct kvmppc_xive *kvmppc_xive_get_device(struct kvm *kvm, u32 type);
#endif /* CONFIG_KVM_XICS */
#endif /* _KVM_PPC_BOOK3S_XICS_H */