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Diffstat (limited to '')
| -rw-r--r-- | arch/powerpc/kvm/book3s_xive.c | 2984 |
1 files changed, 2984 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c new file mode 100644 index 000000000..4ca23644f --- /dev/null +++ b/arch/powerpc/kvm/book3s_xive.c @@ -0,0 +1,2984 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2017 Benjamin Herrenschmidt, IBM Corporation. + */ + +#define pr_fmt(fmt) "xive-kvm: " fmt + +#include <linux/kernel.h> +#include <linux/kvm_host.h> +#include <linux/err.h> +#include <linux/gfp.h> +#include <linux/spinlock.h> +#include <linux/delay.h> +#include <linux/percpu.h> +#include <linux/cpumask.h> +#include <linux/uaccess.h> +#include <linux/irqdomain.h> +#include <asm/kvm_book3s.h> +#include <asm/kvm_ppc.h> +#include <asm/hvcall.h> +#include <asm/xics.h> +#include <asm/xive.h> +#include <asm/xive-regs.h> +#include <asm/debug.h> +#include <asm/time.h> +#include <asm/opal.h> + +#include <linux/debugfs.h> +#include <linux/seq_file.h> + +#include "book3s_xive.h" + +#define __x_eoi_page(xd) ((void __iomem *)((xd)->eoi_mmio)) +#define __x_trig_page(xd) ((void __iomem *)((xd)->trig_mmio)) + +/* Dummy interrupt used when taking interrupts out of a queue in H_CPPR */ +#define XICS_DUMMY 1 + +static void xive_vm_ack_pending(struct kvmppc_xive_vcpu *xc) +{ + u8 cppr; + u16 ack; + + /* + * Ensure any previous store to CPPR is ordered vs. + * the subsequent loads from PIPR or ACK. + */ + eieio(); + + /* Perform the acknowledge OS to register cycle. */ + ack = be16_to_cpu(__raw_readw(xive_tima + TM_SPC_ACK_OS_REG)); + + /* Synchronize subsequent queue accesses */ + mb(); + + /* XXX Check grouping level */ + + /* Anything ? */ + if (!((ack >> 8) & TM_QW1_NSR_EO)) + return; + + /* Grab CPPR of the most favored pending interrupt */ + cppr = ack & 0xff; + if (cppr < 8) + xc->pending |= 1 << cppr; + + /* Check consistency */ + if (cppr >= xc->hw_cppr) + pr_warn("KVM-XIVE: CPU %d odd ack CPPR, got %d at %d\n", + smp_processor_id(), cppr, xc->hw_cppr); + + /* + * Update our image of the HW CPPR. We don't yet modify + * xc->cppr, this will be done as we scan for interrupts + * in the queues. + */ + xc->hw_cppr = cppr; +} + +static u8 xive_vm_esb_load(struct xive_irq_data *xd, u32 offset) +{ + u64 val; + + if (offset == XIVE_ESB_SET_PQ_10 && xd->flags & XIVE_IRQ_FLAG_STORE_EOI) + offset |= XIVE_ESB_LD_ST_MO; + + val = __raw_readq(__x_eoi_page(xd) + offset); +#ifdef __LITTLE_ENDIAN__ + val >>= 64-8; +#endif + return (u8)val; +} + + +static void xive_vm_source_eoi(u32 hw_irq, struct xive_irq_data *xd) +{ + /* If the XIVE supports the new "store EOI facility, use it */ + if (xd->flags & XIVE_IRQ_FLAG_STORE_EOI) + __raw_writeq(0, __x_eoi_page(xd) + XIVE_ESB_STORE_EOI); + else if (xd->flags & XIVE_IRQ_FLAG_LSI) { + /* + * For LSIs the HW EOI cycle is used rather than PQ bits, + * as they are automatically re-triggred in HW when still + * pending. + */ + __raw_readq(__x_eoi_page(xd) + XIVE_ESB_LOAD_EOI); + } else { + uint64_t eoi_val; + + /* + * Otherwise for EOI, we use the special MMIO that does + * a clear of both P and Q and returns the old Q, + * except for LSIs where we use the "EOI cycle" special + * load. + * + * This allows us to then do a re-trigger if Q was set + * rather than synthetizing an interrupt in software + */ + eoi_val = xive_vm_esb_load(xd, XIVE_ESB_SET_PQ_00); + + /* Re-trigger if needed */ + if ((eoi_val & 1) && __x_trig_page(xd)) + __raw_writeq(0, __x_trig_page(xd)); + } +} + +enum { + scan_fetch, + scan_poll, + scan_eoi, +}; + +static u32 xive_vm_scan_interrupts(struct kvmppc_xive_vcpu *xc, + u8 pending, int scan_type) +{ + u32 hirq = 0; + u8 prio = 0xff; + + /* Find highest pending priority */ + while ((xc->mfrr != 0xff || pending != 0) && hirq == 0) { + struct xive_q *q; + u32 idx, toggle; + __be32 *qpage; + + /* + * If pending is 0 this will return 0xff which is what + * we want + */ + prio = ffs(pending) - 1; + + /* Don't scan past the guest cppr */ + if (prio >= xc->cppr || prio > 7) { + if (xc->mfrr < xc->cppr) { + prio = xc->mfrr; + hirq = XICS_IPI; + } + break; + } + + /* Grab queue and pointers */ + q = &xc->queues[prio]; + idx = q->idx; + toggle = q->toggle; + + /* + * Snapshot the queue page. The test further down for EOI + * must use the same "copy" that was used by __xive_read_eq + * since qpage can be set concurrently and we don't want + * to miss an EOI. + */ + qpage = READ_ONCE(q->qpage); + +skip_ipi: + /* + * Try to fetch from the queue. Will return 0 for a + * non-queueing priority (ie, qpage = 0). + */ + hirq = __xive_read_eq(qpage, q->msk, &idx, &toggle); + + /* + * If this was a signal for an MFFR change done by + * H_IPI we skip it. Additionally, if we were fetching + * we EOI it now, thus re-enabling reception of a new + * such signal. + * + * We also need to do that if prio is 0 and we had no + * page for the queue. In this case, we have non-queued + * IPI that needs to be EOId. + * + * This is safe because if we have another pending MFRR + * change that wasn't observed above, the Q bit will have + * been set and another occurrence of the IPI will trigger. + */ + if (hirq == XICS_IPI || (prio == 0 && !qpage)) { + if (scan_type == scan_fetch) { + xive_vm_source_eoi(xc->vp_ipi, + &xc->vp_ipi_data); + q->idx = idx; + q->toggle = toggle; + } + /* Loop back on same queue with updated idx/toggle */ + WARN_ON(hirq && hirq != XICS_IPI); + if (hirq) + goto skip_ipi; + } + + /* If it's the dummy interrupt, continue searching */ + if (hirq == XICS_DUMMY) + goto skip_ipi; + + /* Clear the pending bit if the queue is now empty */ + if (!hirq) { + pending &= ~(1 << prio); + + /* + * Check if the queue count needs adjusting due to + * interrupts being moved away. + */ + if (atomic_read(&q->pending_count)) { + int p = atomic_xchg(&q->pending_count, 0); + + if (p) { + WARN_ON(p > atomic_read(&q->count)); + atomic_sub(p, &q->count); + } + } + } + + /* + * If the most favoured prio we found pending is less + * favored (or equal) than a pending IPI, we return + * the IPI instead. + */ + if (prio >= xc->mfrr && xc->mfrr < xc->cppr) { + prio = xc->mfrr; + hirq = XICS_IPI; + break; + } + + /* If fetching, update queue pointers */ + if (scan_type == scan_fetch) { + q->idx = idx; + q->toggle = toggle; + } + } + + /* If we are just taking a "peek", do nothing else */ + if (scan_type == scan_poll) + return hirq; + + /* Update the pending bits */ + xc->pending = pending; + + /* + * If this is an EOI that's it, no CPPR adjustment done here, + * all we needed was cleanup the stale pending bits and check + * if there's anything left. + */ + if (scan_type == scan_eoi) + return hirq; + + /* + * If we found an interrupt, adjust what the guest CPPR should + * be as if we had just fetched that interrupt from HW. + * + * Note: This can only make xc->cppr smaller as the previous + * loop will only exit with hirq != 0 if prio is lower than + * the current xc->cppr. Thus we don't need to re-check xc->mfrr + * for pending IPIs. + */ + if (hirq) + xc->cppr = prio; + /* + * If it was an IPI the HW CPPR might have been lowered too much + * as the HW interrupt we use for IPIs is routed to priority 0. + * + * We re-sync it here. + */ + if (xc->cppr != xc->hw_cppr) { + xc->hw_cppr = xc->cppr; + __raw_writeb(xc->cppr, xive_tima + TM_QW1_OS + TM_CPPR); + } + + return hirq; +} + +static unsigned long xive_vm_h_xirr(struct kvm_vcpu *vcpu) +{ + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + u8 old_cppr; + u32 hirq; + + pr_devel("H_XIRR\n"); + + xc->stat_vm_h_xirr++; + + /* First collect pending bits from HW */ + xive_vm_ack_pending(xc); + + pr_devel(" new pending=0x%02x hw_cppr=%d cppr=%d\n", + xc->pending, xc->hw_cppr, xc->cppr); + + /* Grab previous CPPR and reverse map it */ + old_cppr = xive_prio_to_guest(xc->cppr); + + /* Scan for actual interrupts */ + hirq = xive_vm_scan_interrupts(xc, xc->pending, scan_fetch); + + pr_devel(" got hirq=0x%x hw_cppr=%d cppr=%d\n", + hirq, xc->hw_cppr, xc->cppr); + + /* That should never hit */ + if (hirq & 0xff000000) + pr_warn("XIVE: Weird guest interrupt number 0x%08x\n", hirq); + + /* + * XXX We could check if the interrupt is masked here and + * filter it. If we chose to do so, we would need to do: + * + * if (masked) { + * lock(); + * if (masked) { + * old_Q = true; + * hirq = 0; + * } + * unlock(); + * } + */ + + /* Return interrupt and old CPPR in GPR4 */ + vcpu->arch.regs.gpr[4] = hirq | (old_cppr << 24); + + return H_SUCCESS; +} + +static unsigned long xive_vm_h_ipoll(struct kvm_vcpu *vcpu, unsigned long server) +{ + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + u8 pending = xc->pending; + u32 hirq; + + pr_devel("H_IPOLL(server=%ld)\n", server); + + xc->stat_vm_h_ipoll++; + + /* Grab the target VCPU if not the current one */ + if (xc->server_num != server) { + vcpu = kvmppc_xive_find_server(vcpu->kvm, server); + if (!vcpu) + return H_PARAMETER; + xc = vcpu->arch.xive_vcpu; + + /* Scan all priorities */ + pending = 0xff; + } else { + /* Grab pending interrupt if any */ + __be64 qw1 = __raw_readq(xive_tima + TM_QW1_OS); + u8 pipr = be64_to_cpu(qw1) & 0xff; + + if (pipr < 8) + pending |= 1 << pipr; + } + + hirq = xive_vm_scan_interrupts(xc, pending, scan_poll); + + /* Return interrupt and old CPPR in GPR4 */ + vcpu->arch.regs.gpr[4] = hirq | (xc->cppr << 24); + + return H_SUCCESS; +} + +static void xive_vm_push_pending_to_hw(struct kvmppc_xive_vcpu *xc) +{ + u8 pending, prio; + + pending = xc->pending; + if (xc->mfrr != 0xff) { + if (xc->mfrr < 8) + pending |= 1 << xc->mfrr; + else + pending |= 0x80; + } + if (!pending) + return; + prio = ffs(pending) - 1; + + __raw_writeb(prio, xive_tima + TM_SPC_SET_OS_PENDING); +} + +static void xive_vm_scan_for_rerouted_irqs(struct kvmppc_xive *xive, + struct kvmppc_xive_vcpu *xc) +{ + unsigned int prio; + + /* For each priority that is now masked */ + for (prio = xc->cppr; prio < KVMPPC_XIVE_Q_COUNT; prio++) { + struct xive_q *q = &xc->queues[prio]; + struct kvmppc_xive_irq_state *state; + struct kvmppc_xive_src_block *sb; + u32 idx, toggle, entry, irq, hw_num; + struct xive_irq_data *xd; + __be32 *qpage; + u16 src; + + idx = q->idx; + toggle = q->toggle; + qpage = READ_ONCE(q->qpage); + if (!qpage) + continue; + + /* For each interrupt in the queue */ + for (;;) { + entry = be32_to_cpup(qpage + idx); + + /* No more ? */ + if ((entry >> 31) == toggle) + break; + irq = entry & 0x7fffffff; + + /* Skip dummies and IPIs */ + if (irq == XICS_DUMMY || irq == XICS_IPI) + goto next; + sb = kvmppc_xive_find_source(xive, irq, &src); + if (!sb) + goto next; + state = &sb->irq_state[src]; + + /* Has it been rerouted ? */ + if (xc->server_num == state->act_server) + goto next; + + /* + * Allright, it *has* been re-routed, kill it from + * the queue. + */ + qpage[idx] = cpu_to_be32((entry & 0x80000000) | XICS_DUMMY); + + /* Find the HW interrupt */ + kvmppc_xive_select_irq(state, &hw_num, &xd); + + /* If it's not an LSI, set PQ to 11 the EOI will force a resend */ + if (!(xd->flags & XIVE_IRQ_FLAG_LSI)) + xive_vm_esb_load(xd, XIVE_ESB_SET_PQ_11); + + /* EOI the source */ + xive_vm_source_eoi(hw_num, xd); + +next: + idx = (idx + 1) & q->msk; + if (idx == 0) + toggle ^= 1; + } + } +} + +static int xive_vm_h_cppr(struct kvm_vcpu *vcpu, unsigned long cppr) +{ + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + struct kvmppc_xive *xive = vcpu->kvm->arch.xive; + u8 old_cppr; + + pr_devel("H_CPPR(cppr=%ld)\n", cppr); + + xc->stat_vm_h_cppr++; + + /* Map CPPR */ + cppr = xive_prio_from_guest(cppr); + + /* Remember old and update SW state */ + old_cppr = xc->cppr; + xc->cppr = cppr; + + /* + * Order the above update of xc->cppr with the subsequent + * read of xc->mfrr inside push_pending_to_hw() + */ + smp_mb(); + + if (cppr > old_cppr) { + /* + * We are masking less, we need to look for pending things + * to deliver and set VP pending bits accordingly to trigger + * a new interrupt otherwise we might miss MFRR changes for + * which we have optimized out sending an IPI signal. + */ + xive_vm_push_pending_to_hw(xc); + } else { + /* + * We are masking more, we need to check the queue for any + * interrupt that has been routed to another CPU, take + * it out (replace it with the dummy) and retrigger it. + * + * This is necessary since those interrupts may otherwise + * never be processed, at least not until this CPU restores + * its CPPR. + * + * This is in theory racy vs. HW adding new interrupts to + * the queue. In practice this works because the interesting + * cases are when the guest has done a set_xive() to move the + * interrupt away, which flushes the xive, followed by the + * target CPU doing a H_CPPR. So any new interrupt coming into + * the queue must still be routed to us and isn't a source + * of concern. + */ + xive_vm_scan_for_rerouted_irqs(xive, xc); + } + + /* Apply new CPPR */ + xc->hw_cppr = cppr; + __raw_writeb(cppr, xive_tima + TM_QW1_OS + TM_CPPR); + + return H_SUCCESS; +} + +static int xive_vm_h_eoi(struct kvm_vcpu *vcpu, unsigned long xirr) +{ + struct kvmppc_xive *xive = vcpu->kvm->arch.xive; + struct kvmppc_xive_src_block *sb; + struct kvmppc_xive_irq_state *state; + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + struct xive_irq_data *xd; + u8 new_cppr = xirr >> 24; + u32 irq = xirr & 0x00ffffff, hw_num; + u16 src; + int rc = 0; + + pr_devel("H_EOI(xirr=%08lx)\n", xirr); + + xc->stat_vm_h_eoi++; + + xc->cppr = xive_prio_from_guest(new_cppr); + + /* + * IPIs are synthetized from MFRR and thus don't need + * any special EOI handling. The underlying interrupt + * used to signal MFRR changes is EOId when fetched from + * the queue. + */ + if (irq == XICS_IPI || irq == 0) { + /* + * This barrier orders the setting of xc->cppr vs. + * subsquent test of xc->mfrr done inside + * scan_interrupts and push_pending_to_hw + */ + smp_mb(); + goto bail; + } + + /* Find interrupt source */ + sb = kvmppc_xive_find_source(xive, irq, &src); + if (!sb) { + pr_devel(" source not found !\n"); + rc = H_PARAMETER; + /* Same as above */ + smp_mb(); + goto bail; + } + state = &sb->irq_state[src]; + kvmppc_xive_select_irq(state, &hw_num, &xd); + + state->in_eoi = true; + + /* + * This barrier orders both setting of in_eoi above vs, + * subsequent test of guest_priority, and the setting + * of xc->cppr vs. subsquent test of xc->mfrr done inside + * scan_interrupts and push_pending_to_hw + */ + smp_mb(); + +again: + if (state->guest_priority == MASKED) { + arch_spin_lock(&sb->lock); + if (state->guest_priority != MASKED) { + arch_spin_unlock(&sb->lock); + goto again; + } + pr_devel(" EOI on saved P...\n"); + + /* Clear old_p, that will cause unmask to perform an EOI */ + state->old_p = false; + + arch_spin_unlock(&sb->lock); + } else { + pr_devel(" EOI on source...\n"); + + /* Perform EOI on the source */ + xive_vm_source_eoi(hw_num, xd); + + /* If it's an emulated LSI, check level and resend */ + if (state->lsi && state->asserted) + __raw_writeq(0, __x_trig_page(xd)); + + } + + /* + * This barrier orders the above guest_priority check + * and spin_lock/unlock with clearing in_eoi below. + * + * It also has to be a full mb() as it must ensure + * the MMIOs done in source_eoi() are completed before + * state->in_eoi is visible. + */ + mb(); + state->in_eoi = false; +bail: + + /* Re-evaluate pending IRQs and update HW */ + xive_vm_scan_interrupts(xc, xc->pending, scan_eoi); + xive_vm_push_pending_to_hw(xc); + pr_devel(" after scan pending=%02x\n", xc->pending); + + /* Apply new CPPR */ + xc->hw_cppr = xc->cppr; + __raw_writeb(xc->cppr, xive_tima + TM_QW1_OS + TM_CPPR); + + return rc; +} + +static int xive_vm_h_ipi(struct kvm_vcpu *vcpu, unsigned long server, + unsigned long mfrr) +{ + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + + pr_devel("H_IPI(server=%08lx,mfrr=%ld)\n", server, mfrr); + + xc->stat_vm_h_ipi++; + + /* Find target */ + vcpu = kvmppc_xive_find_server(vcpu->kvm, server); + if (!vcpu) + return H_PARAMETER; + xc = vcpu->arch.xive_vcpu; + + /* Locklessly write over MFRR */ + xc->mfrr = mfrr; + + /* + * The load of xc->cppr below and the subsequent MMIO store + * to the IPI must happen after the above mfrr update is + * globally visible so that: + * + * - Synchronize with another CPU doing an H_EOI or a H_CPPR + * updating xc->cppr then reading xc->mfrr. + * + * - The target of the IPI sees the xc->mfrr update + */ + mb(); + + /* Shoot the IPI if most favored than target cppr */ + if (mfrr < xc->cppr) + __raw_writeq(0, __x_trig_page(&xc->vp_ipi_data)); + + return H_SUCCESS; +} + +/* + * We leave a gap of a couple of interrupts in the queue to + * account for the IPI and additional safety guard. + */ +#define XIVE_Q_GAP 2 + +static bool kvmppc_xive_vcpu_has_save_restore(struct kvm_vcpu *vcpu) +{ + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + + /* Check enablement at VP level */ + return xc->vp_cam & TM_QW1W2_HO; +} + +bool kvmppc_xive_check_save_restore(struct kvm_vcpu *vcpu) +{ + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + struct kvmppc_xive *xive = xc->xive; + + if (xive->flags & KVMPPC_XIVE_FLAG_SAVE_RESTORE) + return kvmppc_xive_vcpu_has_save_restore(vcpu); + + return true; +} + +/* + * Push a vcpu's context to the XIVE on guest entry. + * This assumes we are in virtual mode (MMU on) + */ +void kvmppc_xive_push_vcpu(struct kvm_vcpu *vcpu) +{ + void __iomem *tima = local_paca->kvm_hstate.xive_tima_virt; + u64 pq; + + /* + * Nothing to do if the platform doesn't have a XIVE + * or this vCPU doesn't have its own XIVE context + * (e.g. because it's not using an in-kernel interrupt controller). + */ + if (!tima || !vcpu->arch.xive_cam_word) + return; + + eieio(); + if (!kvmppc_xive_vcpu_has_save_restore(vcpu)) + __raw_writeq(vcpu->arch.xive_saved_state.w01, tima + TM_QW1_OS); + __raw_writel(vcpu->arch.xive_cam_word, tima + TM_QW1_OS + TM_WORD2); + vcpu->arch.xive_pushed = 1; + eieio(); + + /* + * We clear the irq_pending flag. There is a small chance of a + * race vs. the escalation interrupt happening on another + * processor setting it again, but the only consequence is to + * cause a spurious wakeup on the next H_CEDE, which is not an + * issue. + */ + vcpu->arch.irq_pending = 0; + + /* + * In single escalation mode, if the escalation interrupt is + * on, we mask it. + */ + if (vcpu->arch.xive_esc_on) { + pq = __raw_readq((void __iomem *)(vcpu->arch.xive_esc_vaddr + + XIVE_ESB_SET_PQ_01)); + mb(); + + /* + * We have a possible subtle race here: The escalation + * interrupt might have fired and be on its way to the + * host queue while we mask it, and if we unmask it + * early enough (re-cede right away), there is a + * theoretical possibility that it fires again, thus + * landing in the target queue more than once which is + * a big no-no. + * + * Fortunately, solving this is rather easy. If the + * above load setting PQ to 01 returns a previous + * value where P is set, then we know the escalation + * interrupt is somewhere on its way to the host. In + * that case we simply don't clear the xive_esc_on + * flag below. It will be eventually cleared by the + * handler for the escalation interrupt. + * + * Then, when doing a cede, we check that flag again + * before re-enabling the escalation interrupt, and if + * set, we abort the cede. + */ + if (!(pq & XIVE_ESB_VAL_P)) + /* Now P is 0, we can clear the flag */ + vcpu->arch.xive_esc_on = 0; + } +} +EXPORT_SYMBOL_GPL(kvmppc_xive_push_vcpu); + +/* + * Pull a vcpu's context from the XIVE on guest exit. + * This assumes we are in virtual mode (MMU on) + */ +void kvmppc_xive_pull_vcpu(struct kvm_vcpu *vcpu) +{ + void __iomem *tima = local_paca->kvm_hstate.xive_tima_virt; + + if (!vcpu->arch.xive_pushed) + return; + + /* + * Should not have been pushed if there is no tima + */ + if (WARN_ON(!tima)) + return; + + eieio(); + /* First load to pull the context, we ignore the value */ + __raw_readl(tima + TM_SPC_PULL_OS_CTX); + /* Second load to recover the context state (Words 0 and 1) */ + if (!kvmppc_xive_vcpu_has_save_restore(vcpu)) + vcpu->arch.xive_saved_state.w01 = __raw_readq(tima + TM_QW1_OS); + + /* Fixup some of the state for the next load */ + vcpu->arch.xive_saved_state.lsmfb = 0; + vcpu->arch.xive_saved_state.ack = 0xff; + vcpu->arch.xive_pushed = 0; + eieio(); +} +EXPORT_SYMBOL_GPL(kvmppc_xive_pull_vcpu); + +bool kvmppc_xive_rearm_escalation(struct kvm_vcpu *vcpu) +{ + void __iomem *esc_vaddr = (void __iomem *)vcpu->arch.xive_esc_vaddr; + bool ret = true; + + if (!esc_vaddr) + return ret; + + /* we are using XIVE with single escalation */ + + if (vcpu->arch.xive_esc_on) { + /* + * If we still have a pending escalation, abort the cede, + * and we must set PQ to 10 rather than 00 so that we don't + * potentially end up with two entries for the escalation + * interrupt in the XIVE interrupt queue. In that case + * we also don't want to set xive_esc_on to 1 here in + * case we race with xive_esc_irq(). + */ + ret = false; + /* + * The escalation interrupts are special as we don't EOI them. + * There is no need to use the load-after-store ordering offset + * to set PQ to 10 as we won't use StoreEOI. + */ + __raw_readq(esc_vaddr + XIVE_ESB_SET_PQ_10); + } else { + vcpu->arch.xive_esc_on = true; + mb(); + __raw_readq(esc_vaddr + XIVE_ESB_SET_PQ_00); + } + mb(); + + return ret; +} +EXPORT_SYMBOL_GPL(kvmppc_xive_rearm_escalation); + +/* + * This is a simple trigger for a generic XIVE IRQ. This must + * only be called for interrupts that support a trigger page + */ +static bool xive_irq_trigger(struct xive_irq_data *xd) +{ + /* This should be only for MSIs */ + if (WARN_ON(xd->flags & XIVE_IRQ_FLAG_LSI)) + return false; + + /* Those interrupts should always have a trigger page */ + if (WARN_ON(!xd->trig_mmio)) + return false; + + out_be64(xd->trig_mmio, 0); + + return true; +} + +static irqreturn_t xive_esc_irq(int irq, void *data) +{ + struct kvm_vcpu *vcpu = data; + + vcpu->arch.irq_pending = 1; + smp_mb(); + if (vcpu->arch.ceded || vcpu->arch.nested) + kvmppc_fast_vcpu_kick(vcpu); + + /* Since we have the no-EOI flag, the interrupt is effectively + * disabled now. Clearing xive_esc_on means we won't bother + * doing so on the next entry. + * + * This also allows the entry code to know that if a PQ combination + * of 10 is observed while xive_esc_on is true, it means the queue + * contains an unprocessed escalation interrupt. We don't make use of + * that knowledge today but might (see comment in book3s_hv_rmhandler.S) + */ + vcpu->arch.xive_esc_on = false; + + /* This orders xive_esc_on = false vs. subsequent stale_p = true */ + smp_wmb(); /* goes with smp_mb() in cleanup_single_escalation */ + + return IRQ_HANDLED; +} + +int kvmppc_xive_attach_escalation(struct kvm_vcpu *vcpu, u8 prio, + bool single_escalation) +{ + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + struct xive_q *q = &xc->queues[prio]; + char *name = NULL; + int rc; + + /* Already there ? */ + if (xc->esc_virq[prio]) + return 0; + + /* Hook up the escalation interrupt */ + xc->esc_virq[prio] = irq_create_mapping(NULL, q->esc_irq); + if (!xc->esc_virq[prio]) { + pr_err("Failed to map escalation interrupt for queue %d of VCPU %d\n", + prio, xc->server_num); + return -EIO; + } + + if (single_escalation) + name = kasprintf(GFP_KERNEL, "kvm-%d-%d", + vcpu->kvm->arch.lpid, xc->server_num); + else + name = kasprintf(GFP_KERNEL, "kvm-%d-%d-%d", + vcpu->kvm->arch.lpid, xc->server_num, prio); + if (!name) { + pr_err("Failed to allocate escalation irq name for queue %d of VCPU %d\n", + prio, xc->server_num); + rc = -ENOMEM; + goto error; + } + + pr_devel("Escalation %s irq %d (prio %d)\n", name, xc->esc_virq[prio], prio); + + rc = request_irq(xc->esc_virq[prio], xive_esc_irq, + IRQF_NO_THREAD, name, vcpu); + if (rc) { + pr_err("Failed to request escalation interrupt for queue %d of VCPU %d\n", + prio, xc->server_num); + goto error; + } + xc->esc_virq_names[prio] = name; + + /* In single escalation mode, we grab the ESB MMIO of the + * interrupt and mask it. Also populate the VCPU v/raddr + * of the ESB page for use by asm entry/exit code. Finally + * set the XIVE_IRQ_FLAG_NO_EOI flag which will prevent the + * core code from performing an EOI on the escalation + * interrupt, thus leaving it effectively masked after + * it fires once. + */ + if (single_escalation) { + struct irq_data *d = irq_get_irq_data(xc->esc_virq[prio]); + struct xive_irq_data *xd = irq_data_get_irq_handler_data(d); + + xive_vm_esb_load(xd, XIVE_ESB_SET_PQ_01); + vcpu->arch.xive_esc_raddr = xd->eoi_page; + vcpu->arch.xive_esc_vaddr = (__force u64)xd->eoi_mmio; + xd->flags |= XIVE_IRQ_FLAG_NO_EOI; + } + + return 0; +error: + irq_dispose_mapping(xc->esc_virq[prio]); + xc->esc_virq[prio] = 0; + kfree(name); + return rc; +} + +static int xive_provision_queue(struct kvm_vcpu *vcpu, u8 prio) +{ + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + struct kvmppc_xive *xive = xc->xive; + struct xive_q *q = &xc->queues[prio]; + void *qpage; + int rc; + + if (WARN_ON(q->qpage)) + return 0; + + /* Allocate the queue and retrieve infos on current node for now */ + qpage = (__be32 *)__get_free_pages(GFP_KERNEL, xive->q_page_order); + if (!qpage) { + pr_err("Failed to allocate queue %d for VCPU %d\n", + prio, xc->server_num); + return -ENOMEM; + } + memset(qpage, 0, 1 << xive->q_order); + + /* + * Reconfigure the queue. This will set q->qpage only once the + * queue is fully configured. This is a requirement for prio 0 + * as we will stop doing EOIs for every IPI as soon as we observe + * qpage being non-NULL, and instead will only EOI when we receive + * corresponding queue 0 entries + */ + rc = xive_native_configure_queue(xc->vp_id, q, prio, qpage, + xive->q_order, true); + if (rc) + pr_err("Failed to configure queue %d for VCPU %d\n", + prio, xc->server_num); + return rc; +} + +/* Called with xive->lock held */ +static int xive_check_provisioning(struct kvm *kvm, u8 prio) +{ + struct kvmppc_xive *xive = kvm->arch.xive; + struct kvm_vcpu *vcpu; + unsigned long i; + int rc; + + lockdep_assert_held(&xive->lock); + + /* Already provisioned ? */ + if (xive->qmap & (1 << prio)) + return 0; + + pr_devel("Provisioning prio... %d\n", prio); + + /* Provision each VCPU and enable escalations if needed */ + kvm_for_each_vcpu(i, vcpu, kvm) { + if (!vcpu->arch.xive_vcpu) + continue; + rc = xive_provision_queue(vcpu, prio); + if (rc == 0 && !kvmppc_xive_has_single_escalation(xive)) + kvmppc_xive_attach_escalation(vcpu, prio, + kvmppc_xive_has_single_escalation(xive)); + if (rc) + return rc; + } + + /* Order previous stores and mark it as provisioned */ + mb(); + xive->qmap |= (1 << prio); + return 0; +} + +static void xive_inc_q_pending(struct kvm *kvm, u32 server, u8 prio) +{ + struct kvm_vcpu *vcpu; + struct kvmppc_xive_vcpu *xc; + struct xive_q *q; + + /* Locate target server */ + vcpu = kvmppc_xive_find_server(kvm, server); + if (!vcpu) { + pr_warn("%s: Can't find server %d\n", __func__, server); + return; + } + xc = vcpu->arch.xive_vcpu; + if (WARN_ON(!xc)) + return; + + q = &xc->queues[prio]; + atomic_inc(&q->pending_count); +} + +static int xive_try_pick_queue(struct kvm_vcpu *vcpu, u8 prio) +{ + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + struct xive_q *q; + u32 max; + + if (WARN_ON(!xc)) + return -ENXIO; + if (!xc->valid) + return -ENXIO; + + q = &xc->queues[prio]; + if (WARN_ON(!q->qpage)) + return -ENXIO; + + /* Calculate max number of interrupts in that queue. */ + max = (q->msk + 1) - XIVE_Q_GAP; + return atomic_add_unless(&q->count, 1, max) ? 0 : -EBUSY; +} + +int kvmppc_xive_select_target(struct kvm *kvm, u32 *server, u8 prio) +{ + struct kvm_vcpu *vcpu; + unsigned long i; + int rc; + + /* Locate target server */ + vcpu = kvmppc_xive_find_server(kvm, *server); + if (!vcpu) { + pr_devel("Can't find server %d\n", *server); + return -EINVAL; + } + + pr_devel("Finding irq target on 0x%x/%d...\n", *server, prio); + + /* Try pick it */ + rc = xive_try_pick_queue(vcpu, prio); + if (rc == 0) + return rc; + + pr_devel(" .. failed, looking up candidate...\n"); + + /* Failed, pick another VCPU */ + kvm_for_each_vcpu(i, vcpu, kvm) { + if (!vcpu->arch.xive_vcpu) + continue; + rc = xive_try_pick_queue(vcpu, prio); + if (rc == 0) { + *server = vcpu->arch.xive_vcpu->server_num; + pr_devel(" found on 0x%x/%d\n", *server, prio); + return rc; + } + } + pr_devel(" no available target !\n"); + + /* No available target ! */ + return -EBUSY; +} + +static u8 xive_lock_and_mask(struct kvmppc_xive *xive, + struct kvmppc_xive_src_block *sb, + struct kvmppc_xive_irq_state *state) +{ + struct xive_irq_data *xd; + u32 hw_num; + u8 old_prio; + u64 val; + + /* + * Take the lock, set masked, try again if racing + * with H_EOI + */ + for (;;) { + arch_spin_lock(&sb->lock); + old_prio = state->guest_priority; + state->guest_priority = MASKED; + mb(); + if (!state->in_eoi) + break; + state->guest_priority = old_prio; + arch_spin_unlock(&sb->lock); + } + + /* No change ? Bail */ + if (old_prio == MASKED) + return old_prio; + + /* Get the right irq */ + kvmppc_xive_select_irq(state, &hw_num, &xd); + + /* Set PQ to 10, return old P and old Q and remember them */ + val = xive_vm_esb_load(xd, XIVE_ESB_SET_PQ_10); + state->old_p = !!(val & 2); + state->old_q = !!(val & 1); + + /* + * Synchronize hardware to sensure the queues are updated when + * masking + */ + xive_native_sync_source(hw_num); + + return old_prio; +} + +static void xive_lock_for_unmask(struct kvmppc_xive_src_block *sb, + struct kvmppc_xive_irq_state *state) +{ + /* + * Take the lock try again if racing with H_EOI + */ + for (;;) { + arch_spin_lock(&sb->lock); + if (!state->in_eoi) + break; + arch_spin_unlock(&sb->lock); + } +} + +static void xive_finish_unmask(struct kvmppc_xive *xive, + struct kvmppc_xive_src_block *sb, + struct kvmppc_xive_irq_state *state, + u8 prio) +{ + struct xive_irq_data *xd; + u32 hw_num; + + /* If we aren't changing a thing, move on */ + if (state->guest_priority != MASKED) + goto bail; + + /* Get the right irq */ + kvmppc_xive_select_irq(state, &hw_num, &xd); + + /* Old Q set, set PQ to 11 */ + if (state->old_q) + xive_vm_esb_load(xd, XIVE_ESB_SET_PQ_11); + + /* + * If not old P, then perform an "effective" EOI, + * on the source. This will handle the cases where + * FW EOI is needed. + */ + if (!state->old_p) + xive_vm_source_eoi(hw_num, xd); + + /* Synchronize ordering and mark unmasked */ + mb(); +bail: + state->guest_priority = prio; +} + +/* + * Target an interrupt to a given server/prio, this will fallback + * to another server if necessary and perform the HW targetting + * updates as needed + * + * NOTE: Must be called with the state lock held + */ +static int xive_target_interrupt(struct kvm *kvm, + struct kvmppc_xive_irq_state *state, + u32 server, u8 prio) +{ + struct kvmppc_xive *xive = kvm->arch.xive; + u32 hw_num; + int rc; + + /* + * This will return a tentative server and actual + * priority. The count for that new target will have + * already been incremented. + */ + rc = kvmppc_xive_select_target(kvm, &server, prio); + + /* + * We failed to find a target ? Not much we can do + * at least until we support the GIQ. + */ + if (rc) + return rc; + + /* + * Increment the old queue pending count if there + * was one so that the old queue count gets adjusted later + * when observed to be empty. + */ + if (state->act_priority != MASKED) + xive_inc_q_pending(kvm, + state->act_server, + state->act_priority); + /* + * Update state and HW + */ + state->act_priority = prio; + state->act_server = server; + + /* Get the right irq */ + kvmppc_xive_select_irq(state, &hw_num, NULL); + + return xive_native_configure_irq(hw_num, + kvmppc_xive_vp(xive, server), + prio, state->number); +} + +/* + * Targetting rules: In order to avoid losing track of + * pending interrupts across mask and unmask, which would + * allow queue overflows, we implement the following rules: + * + * - Unless it was never enabled (or we run out of capacity) + * an interrupt is always targetted at a valid server/queue + * pair even when "masked" by the guest. This pair tends to + * be the last one used but it can be changed under some + * circumstances. That allows us to separate targetting + * from masking, we only handle accounting during (re)targetting, + * this also allows us to let an interrupt drain into its target + * queue after masking, avoiding complex schemes to remove + * interrupts out of remote processor queues. + * + * - When masking, we set PQ to 10 and save the previous value + * of P and Q. + * + * - When unmasking, if saved Q was set, we set PQ to 11 + * otherwise we leave PQ to the HW state which will be either + * 10 if nothing happened or 11 if the interrupt fired while + * masked. Effectively we are OR'ing the previous Q into the + * HW Q. + * + * Then if saved P is clear, we do an effective EOI (Q->P->Trigger) + * which will unmask the interrupt and shoot a new one if Q was + * set. + * + * Otherwise (saved P is set) we leave PQ unchanged (so 10 or 11, + * effectively meaning an H_EOI from the guest is still expected + * for that interrupt). + * + * - If H_EOI occurs while masked, we clear the saved P. + * + * - When changing target, we account on the new target and + * increment a separate "pending" counter on the old one. + * This pending counter will be used to decrement the old + * target's count when its queue has been observed empty. + */ + +int kvmppc_xive_set_xive(struct kvm *kvm, u32 irq, u32 server, + u32 priority) +{ + struct kvmppc_xive *xive = kvm->arch.xive; + struct kvmppc_xive_src_block *sb; + struct kvmppc_xive_irq_state *state; + u8 new_act_prio; + int rc = 0; + u16 idx; + + if (!xive) + return -ENODEV; + + pr_devel("set_xive ! irq 0x%x server 0x%x prio %d\n", + irq, server, priority); + + /* First, check provisioning of queues */ + if (priority != MASKED) { + mutex_lock(&xive->lock); + rc = xive_check_provisioning(xive->kvm, + xive_prio_from_guest(priority)); + mutex_unlock(&xive->lock); + } + if (rc) { + pr_devel(" provisioning failure %d !\n", rc); + return rc; + } + + sb = kvmppc_xive_find_source(xive, irq, &idx); + if (!sb) + return -EINVAL; + state = &sb->irq_state[idx]; + + /* + * We first handle masking/unmasking since the locking + * might need to be retried due to EOIs, we'll handle + * targetting changes later. These functions will return + * with the SB lock held. + * + * xive_lock_and_mask() will also set state->guest_priority + * but won't otherwise change other fields of the state. + * + * xive_lock_for_unmask will not actually unmask, this will + * be done later by xive_finish_unmask() once the targetting + * has been done, so we don't try to unmask an interrupt + * that hasn't yet been targetted. + */ + if (priority == MASKED) + xive_lock_and_mask(xive, sb, state); + else + xive_lock_for_unmask(sb, state); + + + /* + * Then we handle targetting. + * + * First calculate a new "actual priority" + */ + new_act_prio = state->act_priority; + if (priority != MASKED) + new_act_prio = xive_prio_from_guest(priority); + + pr_devel(" new_act_prio=%x act_server=%x act_prio=%x\n", + new_act_prio, state->act_server, state->act_priority); + + /* + * Then check if we actually need to change anything, + * + * The condition for re-targetting the interrupt is that + * we have a valid new priority (new_act_prio is not 0xff) + * and either the server or the priority changed. + * + * Note: If act_priority was ff and the new priority is + * also ff, we don't do anything and leave the interrupt + * untargetted. An attempt of doing an int_on on an + * untargetted interrupt will fail. If that is a problem + * we could initialize interrupts with valid default + */ + + if (new_act_prio != MASKED && + (state->act_server != server || + state->act_priority != new_act_prio)) + rc = xive_target_interrupt(kvm, state, server, new_act_prio); + + /* + * Perform the final unmasking of the interrupt source + * if necessary + */ + if (priority != MASKED) + xive_finish_unmask(xive, sb, state, priority); + + /* + * Finally Update saved_priority to match. Only int_on/off + * set this field to a different value. + */ + state->saved_priority = priority; + + arch_spin_unlock(&sb->lock); + return rc; +} + +int kvmppc_xive_get_xive(struct kvm *kvm, u32 irq, u32 *server, + u32 *priority) +{ + struct kvmppc_xive *xive = kvm->arch.xive; + struct kvmppc_xive_src_block *sb; + struct kvmppc_xive_irq_state *state; + u16 idx; + + if (!xive) + return -ENODEV; + + sb = kvmppc_xive_find_source(xive, irq, &idx); + if (!sb) + return -EINVAL; + state = &sb->irq_state[idx]; + arch_spin_lock(&sb->lock); + *server = state->act_server; + *priority = state->guest_priority; + arch_spin_unlock(&sb->lock); + + return 0; +} + +int kvmppc_xive_int_on(struct kvm *kvm, u32 irq) +{ + struct kvmppc_xive *xive = kvm->arch.xive; + struct kvmppc_xive_src_block *sb; + struct kvmppc_xive_irq_state *state; + u16 idx; + + if (!xive) + return -ENODEV; + + sb = kvmppc_xive_find_source(xive, irq, &idx); + if (!sb) + return -EINVAL; + state = &sb->irq_state[idx]; + + pr_devel("int_on(irq=0x%x)\n", irq); + + /* + * Check if interrupt was not targetted + */ + if (state->act_priority == MASKED) { + pr_devel("int_on on untargetted interrupt\n"); + return -EINVAL; + } + + /* If saved_priority is 0xff, do nothing */ + if (state->saved_priority == MASKED) + return 0; + + /* + * Lock and unmask it. + */ + xive_lock_for_unmask(sb, state); + xive_finish_unmask(xive, sb, state, state->saved_priority); + arch_spin_unlock(&sb->lock); + + return 0; +} + +int kvmppc_xive_int_off(struct kvm *kvm, u32 irq) +{ + struct kvmppc_xive *xive = kvm->arch.xive; + struct kvmppc_xive_src_block *sb; + struct kvmppc_xive_irq_state *state; + u16 idx; + + if (!xive) + return -ENODEV; + + sb = kvmppc_xive_find_source(xive, irq, &idx); + if (!sb) + return -EINVAL; + state = &sb->irq_state[idx]; + + pr_devel("int_off(irq=0x%x)\n", irq); + + /* + * Lock and mask + */ + state->saved_priority = xive_lock_and_mask(xive, sb, state); + arch_spin_unlock(&sb->lock); + + return 0; +} + +static bool xive_restore_pending_irq(struct kvmppc_xive *xive, u32 irq) +{ + struct kvmppc_xive_src_block *sb; + struct kvmppc_xive_irq_state *state; + u16 idx; + + sb = kvmppc_xive_find_source(xive, irq, &idx); + if (!sb) + return false; + state = &sb->irq_state[idx]; + if (!state->valid) + return false; + + /* + * Trigger the IPI. This assumes we never restore a pass-through + * interrupt which should be safe enough + */ + xive_irq_trigger(&state->ipi_data); + + return true; +} + +u64 kvmppc_xive_get_icp(struct kvm_vcpu *vcpu) +{ + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + + if (!xc) + return 0; + + /* Return the per-cpu state for state saving/migration */ + return (u64)xc->cppr << KVM_REG_PPC_ICP_CPPR_SHIFT | + (u64)xc->mfrr << KVM_REG_PPC_ICP_MFRR_SHIFT | + (u64)0xff << KVM_REG_PPC_ICP_PPRI_SHIFT; +} + +int kvmppc_xive_set_icp(struct kvm_vcpu *vcpu, u64 icpval) +{ + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + struct kvmppc_xive *xive = vcpu->kvm->arch.xive; + u8 cppr, mfrr; + u32 xisr; + + if (!xc || !xive) + return -ENOENT; + + /* Grab individual state fields. We don't use pending_pri */ + cppr = icpval >> KVM_REG_PPC_ICP_CPPR_SHIFT; + xisr = (icpval >> KVM_REG_PPC_ICP_XISR_SHIFT) & + KVM_REG_PPC_ICP_XISR_MASK; + mfrr = icpval >> KVM_REG_PPC_ICP_MFRR_SHIFT; + + pr_devel("set_icp vcpu %d cppr=0x%x mfrr=0x%x xisr=0x%x\n", + xc->server_num, cppr, mfrr, xisr); + + /* + * We can't update the state of a "pushed" VCPU, but that + * shouldn't happen because the vcpu->mutex makes running a + * vcpu mutually exclusive with doing one_reg get/set on it. + */ + if (WARN_ON(vcpu->arch.xive_pushed)) + return -EIO; + + /* Update VCPU HW saved state */ + vcpu->arch.xive_saved_state.cppr = cppr; + xc->hw_cppr = xc->cppr = cppr; + + /* + * Update MFRR state. If it's not 0xff, we mark the VCPU as + * having a pending MFRR change, which will re-evaluate the + * target. The VCPU will thus potentially get a spurious + * interrupt but that's not a big deal. + */ + xc->mfrr = mfrr; + if (mfrr < cppr) + xive_irq_trigger(&xc->vp_ipi_data); + + /* + * Now saved XIRR is "interesting". It means there's something in + * the legacy "1 element" queue... for an IPI we simply ignore it, + * as the MFRR restore will handle that. For anything else we need + * to force a resend of the source. + * However the source may not have been setup yet. If that's the + * case, we keep that info and increment a counter in the xive to + * tell subsequent xive_set_source() to go look. + */ + if (xisr > XICS_IPI && !xive_restore_pending_irq(xive, xisr)) { + xc->delayed_irq = xisr; + xive->delayed_irqs++; + pr_devel(" xisr restore delayed\n"); + } + + return 0; +} + +int kvmppc_xive_set_mapped(struct kvm *kvm, unsigned long guest_irq, + unsigned long host_irq) +{ + struct kvmppc_xive *xive = kvm->arch.xive; + struct kvmppc_xive_src_block *sb; + struct kvmppc_xive_irq_state *state; + struct irq_data *host_data = + irq_domain_get_irq_data(irq_get_default_host(), host_irq); + unsigned int hw_irq = (unsigned int)irqd_to_hwirq(host_data); + u16 idx; + u8 prio; + int rc; + + if (!xive) + return -ENODEV; + + pr_debug("%s: GIRQ 0x%lx host IRQ %ld XIVE HW IRQ 0x%x\n", + __func__, guest_irq, host_irq, hw_irq); + + sb = kvmppc_xive_find_source(xive, guest_irq, &idx); + if (!sb) + return -EINVAL; + state = &sb->irq_state[idx]; + + /* + * Mark the passed-through interrupt as going to a VCPU, + * this will prevent further EOIs and similar operations + * from the XIVE code. It will also mask the interrupt + * to either PQ=10 or 11 state, the latter if the interrupt + * is pending. This will allow us to unmask or retrigger it + * after routing it to the guest with a simple EOI. + * + * The "state" argument is a "token", all it needs is to be + * non-NULL to switch to passed-through or NULL for the + * other way around. We may not yet have an actual VCPU + * target here and we don't really care. + */ + rc = irq_set_vcpu_affinity(host_irq, state); + if (rc) { + pr_err("Failed to set VCPU affinity for host IRQ %ld\n", host_irq); + return rc; + } + + /* + * Mask and read state of IPI. We need to know if its P bit + * is set as that means it's potentially already using a + * queue entry in the target + */ + prio = xive_lock_and_mask(xive, sb, state); + pr_devel(" old IPI prio %02x P:%d Q:%d\n", prio, + state->old_p, state->old_q); + + /* Turn the IPI hard off */ + xive_vm_esb_load(&state->ipi_data, XIVE_ESB_SET_PQ_01); + + /* + * Reset ESB guest mapping. Needed when ESB pages are exposed + * to the guest in XIVE native mode + */ + if (xive->ops && xive->ops->reset_mapped) + xive->ops->reset_mapped(kvm, guest_irq); + + /* Grab info about irq */ + state->pt_number = hw_irq; + state->pt_data = irq_data_get_irq_handler_data(host_data); + + /* + * Configure the IRQ to match the existing configuration of + * the IPI if it was already targetted. Otherwise this will + * mask the interrupt in a lossy way (act_priority is 0xff) + * which is fine for a never started interrupt. + */ + xive_native_configure_irq(hw_irq, + kvmppc_xive_vp(xive, state->act_server), + state->act_priority, state->number); + + /* + * We do an EOI to enable the interrupt (and retrigger if needed) + * if the guest has the interrupt unmasked and the P bit was *not* + * set in the IPI. If it was set, we know a slot may still be in + * use in the target queue thus we have to wait for a guest + * originated EOI + */ + if (prio != MASKED && !state->old_p) + xive_vm_source_eoi(hw_irq, state->pt_data); + + /* Clear old_p/old_q as they are no longer relevant */ + state->old_p = state->old_q = false; + + /* Restore guest prio (unlocks EOI) */ + mb(); + state->guest_priority = prio; + arch_spin_unlock(&sb->lock); + + return 0; +} +EXPORT_SYMBOL_GPL(kvmppc_xive_set_mapped); + +int kvmppc_xive_clr_mapped(struct kvm *kvm, unsigned long guest_irq, + unsigned long host_irq) +{ + struct kvmppc_xive *xive = kvm->arch.xive; + struct kvmppc_xive_src_block *sb; + struct kvmppc_xive_irq_state *state; + u16 idx; + u8 prio; + int rc; + + if (!xive) + return -ENODEV; + + pr_debug("%s: GIRQ 0x%lx host IRQ %ld\n", __func__, guest_irq, host_irq); + + sb = kvmppc_xive_find_source(xive, guest_irq, &idx); + if (!sb) + return -EINVAL; + state = &sb->irq_state[idx]; + + /* + * Mask and read state of IRQ. We need to know if its P bit + * is set as that means it's potentially already using a + * queue entry in the target + */ + prio = xive_lock_and_mask(xive, sb, state); + pr_devel(" old IRQ prio %02x P:%d Q:%d\n", prio, + state->old_p, state->old_q); + + /* + * If old_p is set, the interrupt is pending, we switch it to + * PQ=11. This will force a resend in the host so the interrupt + * isn't lost to whatever host driver may pick it up + */ + if (state->old_p) + xive_vm_esb_load(state->pt_data, XIVE_ESB_SET_PQ_11); + + /* Release the passed-through interrupt to the host */ + rc = irq_set_vcpu_affinity(host_irq, NULL); + if (rc) { + pr_err("Failed to clr VCPU affinity for host IRQ %ld\n", host_irq); + return rc; + } + + /* Forget about the IRQ */ + state->pt_number = 0; + state->pt_data = NULL; + + /* + * Reset ESB guest mapping. Needed when ESB pages are exposed + * to the guest in XIVE native mode + */ + if (xive->ops && xive->ops->reset_mapped) { + xive->ops->reset_mapped(kvm, guest_irq); + } + + /* Reconfigure the IPI */ + xive_native_configure_irq(state->ipi_number, + kvmppc_xive_vp(xive, state->act_server), + state->act_priority, state->number); + + /* + * If old_p is set (we have a queue entry potentially + * occupied) or the interrupt is masked, we set the IPI + * to PQ=10 state. Otherwise we just re-enable it (PQ=00). + */ + if (prio == MASKED || state->old_p) + xive_vm_esb_load(&state->ipi_data, XIVE_ESB_SET_PQ_10); + else + xive_vm_esb_load(&state->ipi_data, XIVE_ESB_SET_PQ_00); + + /* Restore guest prio (unlocks EOI) */ + mb(); + state->guest_priority = prio; + arch_spin_unlock(&sb->lock); + + return 0; +} +EXPORT_SYMBOL_GPL(kvmppc_xive_clr_mapped); + +void kvmppc_xive_disable_vcpu_interrupts(struct kvm_vcpu *vcpu) +{ + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + struct kvm *kvm = vcpu->kvm; + struct kvmppc_xive *xive = kvm->arch.xive; + int i, j; + + for (i = 0; i <= xive->max_sbid; i++) { + struct kvmppc_xive_src_block *sb = xive->src_blocks[i]; + + if (!sb) + continue; + for (j = 0; j < KVMPPC_XICS_IRQ_PER_ICS; j++) { + struct kvmppc_xive_irq_state *state = &sb->irq_state[j]; + + if (!state->valid) + continue; + if (state->act_priority == MASKED) + continue; + if (state->act_server != xc->server_num) + continue; + + /* Clean it up */ + arch_spin_lock(&sb->lock); + state->act_priority = MASKED; + xive_vm_esb_load(&state->ipi_data, XIVE_ESB_SET_PQ_01); + xive_native_configure_irq(state->ipi_number, 0, MASKED, 0); + if (state->pt_number) { + xive_vm_esb_load(state->pt_data, XIVE_ESB_SET_PQ_01); + xive_native_configure_irq(state->pt_number, 0, MASKED, 0); + } + arch_spin_unlock(&sb->lock); + } + } + + /* Disable vcpu's escalation interrupt */ + if (vcpu->arch.xive_esc_on) { + __raw_readq((void __iomem *)(vcpu->arch.xive_esc_vaddr + + XIVE_ESB_SET_PQ_01)); + vcpu->arch.xive_esc_on = false; + } + + /* + * Clear pointers to escalation interrupt ESB. + * This is safe because the vcpu->mutex is held, preventing + * any other CPU from concurrently executing a KVM_RUN ioctl. + */ + vcpu->arch.xive_esc_vaddr = 0; + vcpu->arch.xive_esc_raddr = 0; +} + +/* + * In single escalation mode, the escalation interrupt is marked so + * that EOI doesn't re-enable it, but just sets the stale_p flag to + * indicate that the P bit has already been dealt with. However, the + * assembly code that enters the guest sets PQ to 00 without clearing + * stale_p (because it has no easy way to address it). Hence we have + * to adjust stale_p before shutting down the interrupt. + */ +void xive_cleanup_single_escalation(struct kvm_vcpu *vcpu, + struct kvmppc_xive_vcpu *xc, int irq) +{ + struct irq_data *d = irq_get_irq_data(irq); + struct xive_irq_data *xd = irq_data_get_irq_handler_data(d); + + /* + * This slightly odd sequence gives the right result + * (i.e. stale_p set if xive_esc_on is false) even if + * we race with xive_esc_irq() and xive_irq_eoi(). + */ + xd->stale_p = false; + smp_mb(); /* paired with smb_wmb in xive_esc_irq */ + if (!vcpu->arch.xive_esc_on) + xd->stale_p = true; +} + +void kvmppc_xive_cleanup_vcpu(struct kvm_vcpu *vcpu) +{ + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + struct kvmppc_xive *xive = vcpu->kvm->arch.xive; + int i; + + if (!kvmppc_xics_enabled(vcpu)) + return; + + if (!xc) + return; + + pr_devel("cleanup_vcpu(cpu=%d)\n", xc->server_num); + + /* Ensure no interrupt is still routed to that VP */ + xc->valid = false; + kvmppc_xive_disable_vcpu_interrupts(vcpu); + + /* Mask the VP IPI */ + xive_vm_esb_load(&xc->vp_ipi_data, XIVE_ESB_SET_PQ_01); + + /* Free escalations */ + for (i = 0; i < KVMPPC_XIVE_Q_COUNT; i++) { + if (xc->esc_virq[i]) { + if (kvmppc_xive_has_single_escalation(xc->xive)) + xive_cleanup_single_escalation(vcpu, xc, + xc->esc_virq[i]); + free_irq(xc->esc_virq[i], vcpu); + irq_dispose_mapping(xc->esc_virq[i]); + kfree(xc->esc_virq_names[i]); + } + } + + /* Disable the VP */ + xive_native_disable_vp(xc->vp_id); + + /* Clear the cam word so guest entry won't try to push context */ + vcpu->arch.xive_cam_word = 0; + + /* Free the queues */ + for (i = 0; i < KVMPPC_XIVE_Q_COUNT; i++) { + struct xive_q *q = &xc->queues[i]; + + xive_native_disable_queue(xc->vp_id, q, i); + if (q->qpage) { + free_pages((unsigned long)q->qpage, + xive->q_page_order); + q->qpage = NULL; + } + } + + /* Free the IPI */ + if (xc->vp_ipi) { + xive_cleanup_irq_data(&xc->vp_ipi_data); + xive_native_free_irq(xc->vp_ipi); + } + /* Free the VP */ + kfree(xc); + + /* Cleanup the vcpu */ + vcpu->arch.irq_type = KVMPPC_IRQ_DEFAULT; + vcpu->arch.xive_vcpu = NULL; +} + +static bool kvmppc_xive_vcpu_id_valid(struct kvmppc_xive *xive, u32 cpu) +{ + /* We have a block of xive->nr_servers VPs. We just need to check + * packed vCPU ids are below that. + */ + return kvmppc_pack_vcpu_id(xive->kvm, cpu) < xive->nr_servers; +} + +int kvmppc_xive_compute_vp_id(struct kvmppc_xive *xive, u32 cpu, u32 *vp) +{ + u32 vp_id; + + if (!kvmppc_xive_vcpu_id_valid(xive, cpu)) { + pr_devel("Out of bounds !\n"); + return -EINVAL; + } + + if (xive->vp_base == XIVE_INVALID_VP) { + xive->vp_base = xive_native_alloc_vp_block(xive->nr_servers); + pr_devel("VP_Base=%x nr_servers=%d\n", xive->vp_base, xive->nr_servers); + + if (xive->vp_base == XIVE_INVALID_VP) + return -ENOSPC; + } + + vp_id = kvmppc_xive_vp(xive, cpu); + if (kvmppc_xive_vp_in_use(xive->kvm, vp_id)) { + pr_devel("Duplicate !\n"); + return -EEXIST; + } + + *vp = vp_id; + + return 0; +} + +int kvmppc_xive_connect_vcpu(struct kvm_device *dev, + struct kvm_vcpu *vcpu, u32 cpu) +{ + struct kvmppc_xive *xive = dev->private; + struct kvmppc_xive_vcpu *xc; + int i, r = -EBUSY; + u32 vp_id; + + pr_devel("connect_vcpu(cpu=%d)\n", cpu); + + if (dev->ops != &kvm_xive_ops) { + pr_devel("Wrong ops !\n"); + return -EPERM; + } + if (xive->kvm != vcpu->kvm) + return -EPERM; + if (vcpu->arch.irq_type != KVMPPC_IRQ_DEFAULT) + return -EBUSY; + + /* We need to synchronize with queue provisioning */ + mutex_lock(&xive->lock); + + r = kvmppc_xive_compute_vp_id(xive, cpu, &vp_id); + if (r) + goto bail; + + xc = kzalloc(sizeof(*xc), GFP_KERNEL); + if (!xc) { + r = -ENOMEM; + goto bail; + } + + vcpu->arch.xive_vcpu = xc; + xc->xive = xive; + xc->vcpu = vcpu; + xc->server_num = cpu; + xc->vp_id = vp_id; + xc->mfrr = 0xff; + xc->valid = true; + + r = xive_native_get_vp_info(xc->vp_id, &xc->vp_cam, &xc->vp_chip_id); + if (r) + goto bail; + + if (!kvmppc_xive_check_save_restore(vcpu)) { + pr_err("inconsistent save-restore setup for VCPU %d\n", cpu); + r = -EIO; + goto bail; + } + + /* Configure VCPU fields for use by assembly push/pull */ + vcpu->arch.xive_saved_state.w01 = cpu_to_be64(0xff000000); + vcpu->arch.xive_cam_word = cpu_to_be32(xc->vp_cam | TM_QW1W2_VO); + + /* Allocate IPI */ + xc->vp_ipi = xive_native_alloc_irq(); + if (!xc->vp_ipi) { + pr_err("Failed to allocate xive irq for VCPU IPI\n"); + r = -EIO; + goto bail; + } + pr_devel(" IPI=0x%x\n", xc->vp_ipi); + + r = xive_native_populate_irq_data(xc->vp_ipi, &xc->vp_ipi_data); + if (r) + goto bail; + + /* + * Enable the VP first as the single escalation mode will + * affect escalation interrupts numbering + */ + r = xive_native_enable_vp(xc->vp_id, kvmppc_xive_has_single_escalation(xive)); + if (r) { + pr_err("Failed to enable VP in OPAL, err %d\n", r); + goto bail; + } + + /* + * Initialize queues. Initially we set them all for no queueing + * and we enable escalation for queue 0 only which we'll use for + * our mfrr change notifications. If the VCPU is hot-plugged, we + * do handle provisioning however based on the existing "map" + * of enabled queues. + */ + for (i = 0; i < KVMPPC_XIVE_Q_COUNT; i++) { + struct xive_q *q = &xc->queues[i]; + + /* Single escalation, no queue 7 */ + if (i == 7 && kvmppc_xive_has_single_escalation(xive)) + break; + + /* Is queue already enabled ? Provision it */ + if (xive->qmap & (1 << i)) { + r = xive_provision_queue(vcpu, i); + if (r == 0 && !kvmppc_xive_has_single_escalation(xive)) + kvmppc_xive_attach_escalation( + vcpu, i, kvmppc_xive_has_single_escalation(xive)); + if (r) + goto bail; + } else { + r = xive_native_configure_queue(xc->vp_id, + q, i, NULL, 0, true); + if (r) { + pr_err("Failed to configure queue %d for VCPU %d\n", + i, cpu); + goto bail; + } + } + } + + /* If not done above, attach priority 0 escalation */ + r = kvmppc_xive_attach_escalation(vcpu, 0, kvmppc_xive_has_single_escalation(xive)); + if (r) + goto bail; + + /* Route the IPI */ + r = xive_native_configure_irq(xc->vp_ipi, xc->vp_id, 0, XICS_IPI); + if (!r) + xive_vm_esb_load(&xc->vp_ipi_data, XIVE_ESB_SET_PQ_00); + +bail: + mutex_unlock(&xive->lock); + if (r) { + kvmppc_xive_cleanup_vcpu(vcpu); + return r; + } + + vcpu->arch.irq_type = KVMPPC_IRQ_XICS; + return 0; +} + +/* + * Scanning of queues before/after migration save + */ +static void xive_pre_save_set_queued(struct kvmppc_xive *xive, u32 irq) +{ + struct kvmppc_xive_src_block *sb; + struct kvmppc_xive_irq_state *state; + u16 idx; + + sb = kvmppc_xive_find_source(xive, irq, &idx); + if (!sb) + return; + + state = &sb->irq_state[idx]; + + /* Some sanity checking */ + if (!state->valid) { + pr_err("invalid irq 0x%x in cpu queue!\n", irq); + return; + } + + /* + * If the interrupt is in a queue it should have P set. + * We warn so that gets reported. A backtrace isn't useful + * so no need to use a WARN_ON. + */ + if (!state->saved_p) + pr_err("Interrupt 0x%x is marked in a queue but P not set !\n", irq); + + /* Set flag */ + state->in_queue = true; +} + +static void xive_pre_save_mask_irq(struct kvmppc_xive *xive, + struct kvmppc_xive_src_block *sb, + u32 irq) +{ + struct kvmppc_xive_irq_state *state = &sb->irq_state[irq]; + + if (!state->valid) + return; + + /* Mask and save state, this will also sync HW queues */ + state->saved_scan_prio = xive_lock_and_mask(xive, sb, state); + + /* Transfer P and Q */ + state->saved_p = state->old_p; + state->saved_q = state->old_q; + + /* Unlock */ + arch_spin_unlock(&sb->lock); +} + +static void xive_pre_save_unmask_irq(struct kvmppc_xive *xive, + struct kvmppc_xive_src_block *sb, + u32 irq) +{ + struct kvmppc_xive_irq_state *state = &sb->irq_state[irq]; + + if (!state->valid) + return; + + /* + * Lock / exclude EOI (not technically necessary if the + * guest isn't running concurrently. If this becomes a + * performance issue we can probably remove the lock. + */ + xive_lock_for_unmask(sb, state); + + /* Restore mask/prio if it wasn't masked */ + if (state->saved_scan_prio != MASKED) + xive_finish_unmask(xive, sb, state, state->saved_scan_prio); + + /* Unlock */ + arch_spin_unlock(&sb->lock); +} + +static void xive_pre_save_queue(struct kvmppc_xive *xive, struct xive_q *q) +{ + u32 idx = q->idx; + u32 toggle = q->toggle; + u32 irq; + + do { + irq = __xive_read_eq(q->qpage, q->msk, &idx, &toggle); + if (irq > XICS_IPI) + xive_pre_save_set_queued(xive, irq); + } while(irq); +} + +static void xive_pre_save_scan(struct kvmppc_xive *xive) +{ + struct kvm_vcpu *vcpu = NULL; + unsigned long i; + int j; + + /* + * See comment in xive_get_source() about how this + * work. Collect a stable state for all interrupts + */ + for (i = 0; i <= xive->max_sbid; i++) { + struct kvmppc_xive_src_block *sb = xive->src_blocks[i]; + if (!sb) + continue; + for (j = 0; j < KVMPPC_XICS_IRQ_PER_ICS; j++) + xive_pre_save_mask_irq(xive, sb, j); + } + + /* Then scan the queues and update the "in_queue" flag */ + kvm_for_each_vcpu(i, vcpu, xive->kvm) { + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + if (!xc) + continue; + for (j = 0; j < KVMPPC_XIVE_Q_COUNT; j++) { + if (xc->queues[j].qpage) + xive_pre_save_queue(xive, &xc->queues[j]); + } + } + + /* Finally restore interrupt states */ + for (i = 0; i <= xive->max_sbid; i++) { + struct kvmppc_xive_src_block *sb = xive->src_blocks[i]; + if (!sb) + continue; + for (j = 0; j < KVMPPC_XICS_IRQ_PER_ICS; j++) + xive_pre_save_unmask_irq(xive, sb, j); + } +} + +static void xive_post_save_scan(struct kvmppc_xive *xive) +{ + u32 i, j; + + /* Clear all the in_queue flags */ + for (i = 0; i <= xive->max_sbid; i++) { + struct kvmppc_xive_src_block *sb = xive->src_blocks[i]; + if (!sb) + continue; + for (j = 0; j < KVMPPC_XICS_IRQ_PER_ICS; j++) + sb->irq_state[j].in_queue = false; + } + + /* Next get_source() will do a new scan */ + xive->saved_src_count = 0; +} + +/* + * This returns the source configuration and state to user space. + */ +static int xive_get_source(struct kvmppc_xive *xive, long irq, u64 addr) +{ + struct kvmppc_xive_src_block *sb; + struct kvmppc_xive_irq_state *state; + u64 __user *ubufp = (u64 __user *) addr; + u64 val, prio; + u16 idx; + + sb = kvmppc_xive_find_source(xive, irq, &idx); + if (!sb) + return -ENOENT; + + state = &sb->irq_state[idx]; + + if (!state->valid) + return -ENOENT; + + pr_devel("get_source(%ld)...\n", irq); + + /* + * So to properly save the state into something that looks like a + * XICS migration stream we cannot treat interrupts individually. + * + * We need, instead, mask them all (& save their previous PQ state) + * to get a stable state in the HW, then sync them to ensure that + * any interrupt that had already fired hits its queue, and finally + * scan all the queues to collect which interrupts are still present + * in the queues, so we can set the "pending" flag on them and + * they can be resent on restore. + * + * So we do it all when the "first" interrupt gets saved, all the + * state is collected at that point, the rest of xive_get_source() + * will merely collect and convert that state to the expected + * userspace bit mask. + */ + if (xive->saved_src_count == 0) + xive_pre_save_scan(xive); + xive->saved_src_count++; + + /* Convert saved state into something compatible with xics */ + val = state->act_server; + prio = state->saved_scan_prio; + + if (prio == MASKED) { + val |= KVM_XICS_MASKED; + prio = state->saved_priority; + } + val |= prio << KVM_XICS_PRIORITY_SHIFT; + if (state->lsi) { + val |= KVM_XICS_LEVEL_SENSITIVE; + if (state->saved_p) + val |= KVM_XICS_PENDING; + } else { + if (state->saved_p) + val |= KVM_XICS_PRESENTED; + + if (state->saved_q) + val |= KVM_XICS_QUEUED; + + /* + * We mark it pending (which will attempt a re-delivery) + * if we are in a queue *or* we were masked and had + * Q set which is equivalent to the XICS "masked pending" + * state + */ + if (state->in_queue || (prio == MASKED && state->saved_q)) + val |= KVM_XICS_PENDING; + } + + /* + * If that was the last interrupt saved, reset the + * in_queue flags + */ + if (xive->saved_src_count == xive->src_count) + xive_post_save_scan(xive); + + /* Copy the result to userspace */ + if (put_user(val, ubufp)) + return -EFAULT; + + return 0; +} + +struct kvmppc_xive_src_block *kvmppc_xive_create_src_block( + struct kvmppc_xive *xive, int irq) +{ + struct kvmppc_xive_src_block *sb; + int i, bid; + + bid = irq >> KVMPPC_XICS_ICS_SHIFT; + + mutex_lock(&xive->lock); + + /* block already exists - somebody else got here first */ + if (xive->src_blocks[bid]) + goto out; + + /* Create the ICS */ + sb = kzalloc(sizeof(*sb), GFP_KERNEL); + if (!sb) + goto out; + + sb->id = bid; + + for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) { + sb->irq_state[i].number = (bid << KVMPPC_XICS_ICS_SHIFT) | i; + sb->irq_state[i].eisn = 0; + sb->irq_state[i].guest_priority = MASKED; + sb->irq_state[i].saved_priority = MASKED; + sb->irq_state[i].act_priority = MASKED; + } + smp_wmb(); + xive->src_blocks[bid] = sb; + + if (bid > xive->max_sbid) + xive->max_sbid = bid; + +out: + mutex_unlock(&xive->lock); + return xive->src_blocks[bid]; +} + +static bool xive_check_delayed_irq(struct kvmppc_xive *xive, u32 irq) +{ + struct kvm *kvm = xive->kvm; + struct kvm_vcpu *vcpu = NULL; + unsigned long i; + + kvm_for_each_vcpu(i, vcpu, kvm) { + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + + if (!xc) + continue; + + if (xc->delayed_irq == irq) { + xc->delayed_irq = 0; + xive->delayed_irqs--; + return true; + } + } + return false; +} + +static int xive_set_source(struct kvmppc_xive *xive, long irq, u64 addr) +{ + struct kvmppc_xive_src_block *sb; + struct kvmppc_xive_irq_state *state; + u64 __user *ubufp = (u64 __user *) addr; + u16 idx; + u64 val; + u8 act_prio, guest_prio; + u32 server; + int rc = 0; + + if (irq < KVMPPC_XICS_FIRST_IRQ || irq >= KVMPPC_XICS_NR_IRQS) + return -ENOENT; + + pr_devel("set_source(irq=0x%lx)\n", irq); + + /* Find the source */ + sb = kvmppc_xive_find_source(xive, irq, &idx); + if (!sb) { + pr_devel("No source, creating source block...\n"); + sb = kvmppc_xive_create_src_block(xive, irq); + if (!sb) { + pr_devel("Failed to create block...\n"); + return -ENOMEM; + } + } + state = &sb->irq_state[idx]; + + /* Read user passed data */ + if (get_user(val, ubufp)) { + pr_devel("fault getting user info !\n"); + return -EFAULT; + } + + server = val & KVM_XICS_DESTINATION_MASK; + guest_prio = val >> KVM_XICS_PRIORITY_SHIFT; + + pr_devel(" val=0x016%llx (server=0x%x, guest_prio=%d)\n", + val, server, guest_prio); + + /* + * If the source doesn't already have an IPI, allocate + * one and get the corresponding data + */ + if (!state->ipi_number) { + state->ipi_number = xive_native_alloc_irq(); + if (state->ipi_number == 0) { + pr_devel("Failed to allocate IPI !\n"); + return -ENOMEM; + } + xive_native_populate_irq_data(state->ipi_number, &state->ipi_data); + pr_devel(" src_ipi=0x%x\n", state->ipi_number); + } + + /* + * We use lock_and_mask() to set us in the right masked + * state. We will override that state from the saved state + * further down, but this will handle the cases of interrupts + * that need FW masking. We set the initial guest_priority to + * 0 before calling it to ensure it actually performs the masking. + */ + state->guest_priority = 0; + xive_lock_and_mask(xive, sb, state); + + /* + * Now, we select a target if we have one. If we don't we + * leave the interrupt untargetted. It means that an interrupt + * can become "untargetted" accross migration if it was masked + * by set_xive() but there is little we can do about it. + */ + + /* First convert prio and mark interrupt as untargetted */ + act_prio = xive_prio_from_guest(guest_prio); + state->act_priority = MASKED; + + /* + * We need to drop the lock due to the mutex below. Hopefully + * nothing is touching that interrupt yet since it hasn't been + * advertized to a running guest yet + */ + arch_spin_unlock(&sb->lock); + + /* If we have a priority target the interrupt */ + if (act_prio != MASKED) { + /* First, check provisioning of queues */ + mutex_lock(&xive->lock); + rc = xive_check_provisioning(xive->kvm, act_prio); + mutex_unlock(&xive->lock); + + /* Target interrupt */ + if (rc == 0) + rc = xive_target_interrupt(xive->kvm, state, + server, act_prio); + /* + * If provisioning or targetting failed, leave it + * alone and masked. It will remain disabled until + * the guest re-targets it. + */ + } + + /* + * Find out if this was a delayed irq stashed in an ICP, + * in which case, treat it as pending + */ + if (xive->delayed_irqs && xive_check_delayed_irq(xive, irq)) { + val |= KVM_XICS_PENDING; + pr_devel(" Found delayed ! forcing PENDING !\n"); + } + + /* Cleanup the SW state */ + state->old_p = false; + state->old_q = false; + state->lsi = false; + state->asserted = false; + + /* Restore LSI state */ + if (val & KVM_XICS_LEVEL_SENSITIVE) { + state->lsi = true; + if (val & KVM_XICS_PENDING) + state->asserted = true; + pr_devel(" LSI ! Asserted=%d\n", state->asserted); + } + + /* + * Restore P and Q. If the interrupt was pending, we + * force Q and !P, which will trigger a resend. + * + * That means that a guest that had both an interrupt + * pending (queued) and Q set will restore with only + * one instance of that interrupt instead of 2, but that + * is perfectly fine as coalescing interrupts that haven't + * been presented yet is always allowed. + */ + if (val & KVM_XICS_PRESENTED && !(val & KVM_XICS_PENDING)) + state->old_p = true; + if (val & KVM_XICS_QUEUED || val & KVM_XICS_PENDING) + state->old_q = true; + + pr_devel(" P=%d, Q=%d\n", state->old_p, state->old_q); + + /* + * If the interrupt was unmasked, update guest priority and + * perform the appropriate state transition and do a + * re-trigger if necessary. + */ + if (val & KVM_XICS_MASKED) { + pr_devel(" masked, saving prio\n"); + state->guest_priority = MASKED; + state->saved_priority = guest_prio; + } else { + pr_devel(" unmasked, restoring to prio %d\n", guest_prio); + xive_finish_unmask(xive, sb, state, guest_prio); + state->saved_priority = guest_prio; + } + + /* Increment the number of valid sources and mark this one valid */ + if (!state->valid) + xive->src_count++; + state->valid = true; + + return 0; +} + +int kvmppc_xive_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level, + bool line_status) +{ + struct kvmppc_xive *xive = kvm->arch.xive; + struct kvmppc_xive_src_block *sb; + struct kvmppc_xive_irq_state *state; + u16 idx; + + if (!xive) + return -ENODEV; + + sb = kvmppc_xive_find_source(xive, irq, &idx); + if (!sb) + return -EINVAL; + + /* Perform locklessly .... (we need to do some RCUisms here...) */ + state = &sb->irq_state[idx]; + if (!state->valid) + return -EINVAL; + + /* We don't allow a trigger on a passed-through interrupt */ + if (state->pt_number) + return -EINVAL; + + if ((level == 1 && state->lsi) || level == KVM_INTERRUPT_SET_LEVEL) + state->asserted = true; + else if (level == 0 || level == KVM_INTERRUPT_UNSET) { + state->asserted = false; + return 0; + } + + /* Trigger the IPI */ + xive_irq_trigger(&state->ipi_data); + + return 0; +} + +int kvmppc_xive_set_nr_servers(struct kvmppc_xive *xive, u64 addr) +{ + u32 __user *ubufp = (u32 __user *) addr; + u32 nr_servers; + int rc = 0; + + if (get_user(nr_servers, ubufp)) + return -EFAULT; + + pr_devel("%s nr_servers=%u\n", __func__, nr_servers); + + if (!nr_servers || nr_servers > KVM_MAX_VCPU_IDS) + return -EINVAL; + + mutex_lock(&xive->lock); + if (xive->vp_base != XIVE_INVALID_VP) + /* The VP block is allocated once and freed when the device + * is released. Better not allow to change its size since its + * used by connect_vcpu to validate vCPU ids are valid (eg, + * setting it back to a higher value could allow connect_vcpu + * to come up with a VP id that goes beyond the VP block, which + * is likely to cause a crash in OPAL). + */ + rc = -EBUSY; + else if (nr_servers > KVM_MAX_VCPUS) + /* We don't need more servers. Higher vCPU ids get packed + * down below KVM_MAX_VCPUS by kvmppc_pack_vcpu_id(). + */ + xive->nr_servers = KVM_MAX_VCPUS; + else + xive->nr_servers = nr_servers; + + mutex_unlock(&xive->lock); + + return rc; +} + +static int xive_set_attr(struct kvm_device *dev, struct kvm_device_attr *attr) +{ + struct kvmppc_xive *xive = dev->private; + + /* We honor the existing XICS ioctl */ + switch (attr->group) { + case KVM_DEV_XICS_GRP_SOURCES: + return xive_set_source(xive, attr->attr, attr->addr); + case KVM_DEV_XICS_GRP_CTRL: + switch (attr->attr) { + case KVM_DEV_XICS_NR_SERVERS: + return kvmppc_xive_set_nr_servers(xive, attr->addr); + } + } + return -ENXIO; +} + +static int xive_get_attr(struct kvm_device *dev, struct kvm_device_attr *attr) +{ + struct kvmppc_xive *xive = dev->private; + + /* We honor the existing XICS ioctl */ + switch (attr->group) { + case KVM_DEV_XICS_GRP_SOURCES: + return xive_get_source(xive, attr->attr, attr->addr); + } + return -ENXIO; +} + +static int xive_has_attr(struct kvm_device *dev, struct kvm_device_attr *attr) +{ + /* We honor the same limits as XICS, at least for now */ + switch (attr->group) { + case KVM_DEV_XICS_GRP_SOURCES: + if (attr->attr >= KVMPPC_XICS_FIRST_IRQ && + attr->attr < KVMPPC_XICS_NR_IRQS) + return 0; + break; + case KVM_DEV_XICS_GRP_CTRL: + switch (attr->attr) { + case KVM_DEV_XICS_NR_SERVERS: + return 0; + } + } + return -ENXIO; +} + +static void kvmppc_xive_cleanup_irq(u32 hw_num, struct xive_irq_data *xd) +{ + xive_vm_esb_load(xd, XIVE_ESB_SET_PQ_01); + xive_native_configure_irq(hw_num, 0, MASKED, 0); +} + +void kvmppc_xive_free_sources(struct kvmppc_xive_src_block *sb) +{ + int i; + + for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) { + struct kvmppc_xive_irq_state *state = &sb->irq_state[i]; + + if (!state->valid) + continue; + + kvmppc_xive_cleanup_irq(state->ipi_number, &state->ipi_data); + xive_cleanup_irq_data(&state->ipi_data); + xive_native_free_irq(state->ipi_number); + + /* Pass-through, cleanup too but keep IRQ hw data */ + if (state->pt_number) + kvmppc_xive_cleanup_irq(state->pt_number, state->pt_data); + + state->valid = false; + } +} + +/* + * Called when device fd is closed. kvm->lock is held. + */ +static void kvmppc_xive_release(struct kvm_device *dev) +{ + struct kvmppc_xive *xive = dev->private; + struct kvm *kvm = xive->kvm; + struct kvm_vcpu *vcpu; + unsigned long i; + + pr_devel("Releasing xive device\n"); + + /* + * Since this is the device release function, we know that + * userspace does not have any open fd referring to the + * device. Therefore there can not be any of the device + * attribute set/get functions being executed concurrently, + * and similarly, the connect_vcpu and set/clr_mapped + * functions also cannot be being executed. + */ + + debugfs_remove(xive->dentry); + + /* + * We should clean up the vCPU interrupt presenters first. + */ + kvm_for_each_vcpu(i, vcpu, kvm) { + /* + * Take vcpu->mutex to ensure that no one_reg get/set ioctl + * (i.e. kvmppc_xive_[gs]et_icp) can be done concurrently. + * Holding the vcpu->mutex also means that the vcpu cannot + * be executing the KVM_RUN ioctl, and therefore it cannot + * be executing the XIVE push or pull code or accessing + * the XIVE MMIO regions. + */ + mutex_lock(&vcpu->mutex); + kvmppc_xive_cleanup_vcpu(vcpu); + mutex_unlock(&vcpu->mutex); + } + + /* + * Now that we have cleared vcpu->arch.xive_vcpu, vcpu->arch.irq_type + * and vcpu->arch.xive_esc_[vr]addr on each vcpu, we are safe + * against xive code getting called during vcpu execution or + * set/get one_reg operations. + */ + kvm->arch.xive = NULL; + + /* Mask and free interrupts */ + for (i = 0; i <= xive->max_sbid; i++) { + if (xive->src_blocks[i]) + kvmppc_xive_free_sources(xive->src_blocks[i]); + kfree(xive->src_blocks[i]); + xive->src_blocks[i] = NULL; + } + + if (xive->vp_base != XIVE_INVALID_VP) + xive_native_free_vp_block(xive->vp_base); + + /* + * A reference of the kvmppc_xive pointer is now kept under + * the xive_devices struct of the machine for reuse. It is + * freed when the VM is destroyed for now until we fix all the + * execution paths. + */ + + kfree(dev); +} + +/* + * When the guest chooses the interrupt mode (XICS legacy or XIVE + * native), the VM will switch of KVM device. The previous device will + * be "released" before the new one is created. + * + * Until we are sure all execution paths are well protected, provide a + * fail safe (transitional) method for device destruction, in which + * the XIVE device pointer is recycled and not directly freed. + */ +struct kvmppc_xive *kvmppc_xive_get_device(struct kvm *kvm, u32 type) +{ + struct kvmppc_xive **kvm_xive_device = type == KVM_DEV_TYPE_XIVE ? + &kvm->arch.xive_devices.native : + &kvm->arch.xive_devices.xics_on_xive; + struct kvmppc_xive *xive = *kvm_xive_device; + + if (!xive) { + xive = kzalloc(sizeof(*xive), GFP_KERNEL); + *kvm_xive_device = xive; + } else { + memset(xive, 0, sizeof(*xive)); + } + + return xive; +} + +/* + * Create a XICS device with XIVE backend. kvm->lock is held. + */ +static int kvmppc_xive_create(struct kvm_device *dev, u32 type) +{ + struct kvmppc_xive *xive; + struct kvm *kvm = dev->kvm; + + pr_devel("Creating xive for partition\n"); + + /* Already there ? */ + if (kvm->arch.xive) + return -EEXIST; + + xive = kvmppc_xive_get_device(kvm, type); + if (!xive) + return -ENOMEM; + + dev->private = xive; + xive->dev = dev; + xive->kvm = kvm; + mutex_init(&xive->lock); + + /* We use the default queue size set by the host */ + xive->q_order = xive_native_default_eq_shift(); + if (xive->q_order < PAGE_SHIFT) + xive->q_page_order = 0; + else + xive->q_page_order = xive->q_order - PAGE_SHIFT; + + /* VP allocation is delayed to the first call to connect_vcpu */ + xive->vp_base = XIVE_INVALID_VP; + /* KVM_MAX_VCPUS limits the number of VMs to roughly 64 per sockets + * on a POWER9 system. + */ + xive->nr_servers = KVM_MAX_VCPUS; + + if (xive_native_has_single_escalation()) + xive->flags |= KVMPPC_XIVE_FLAG_SINGLE_ESCALATION; + + if (xive_native_has_save_restore()) + xive->flags |= KVMPPC_XIVE_FLAG_SAVE_RESTORE; + + kvm->arch.xive = xive; + return 0; +} + +int kvmppc_xive_xics_hcall(struct kvm_vcpu *vcpu, u32 req) +{ + struct kvmppc_vcore *vc = vcpu->arch.vcore; + + /* The VM should have configured XICS mode before doing XICS hcalls. */ + if (!kvmppc_xics_enabled(vcpu)) + return H_TOO_HARD; + + switch (req) { + case H_XIRR: + return xive_vm_h_xirr(vcpu); + case H_CPPR: + return xive_vm_h_cppr(vcpu, kvmppc_get_gpr(vcpu, 4)); + case H_EOI: + return xive_vm_h_eoi(vcpu, kvmppc_get_gpr(vcpu, 4)); + case H_IPI: + return xive_vm_h_ipi(vcpu, kvmppc_get_gpr(vcpu, 4), + kvmppc_get_gpr(vcpu, 5)); + case H_IPOLL: + return xive_vm_h_ipoll(vcpu, kvmppc_get_gpr(vcpu, 4)); + case H_XIRR_X: + xive_vm_h_xirr(vcpu); + kvmppc_set_gpr(vcpu, 5, get_tb() + vc->tb_offset); + return H_SUCCESS; + } + + return H_UNSUPPORTED; +} +EXPORT_SYMBOL_GPL(kvmppc_xive_xics_hcall); + +int kvmppc_xive_debug_show_queues(struct seq_file *m, struct kvm_vcpu *vcpu) +{ + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + unsigned int i; + + for (i = 0; i < KVMPPC_XIVE_Q_COUNT; i++) { + struct xive_q *q = &xc->queues[i]; + u32 i0, i1, idx; + + if (!q->qpage && !xc->esc_virq[i]) + continue; + + if (q->qpage) { + seq_printf(m, " q[%d]: ", i); + idx = q->idx; + i0 = be32_to_cpup(q->qpage + idx); + idx = (idx + 1) & q->msk; + i1 = be32_to_cpup(q->qpage + idx); + seq_printf(m, "T=%d %08x %08x...\n", q->toggle, + i0, i1); + } + if (xc->esc_virq[i]) { + struct irq_data *d = irq_get_irq_data(xc->esc_virq[i]); + struct xive_irq_data *xd = + irq_data_get_irq_handler_data(d); + u64 pq = xive_vm_esb_load(xd, XIVE_ESB_GET); + + seq_printf(m, " ESC %d %c%c EOI @%llx", + xc->esc_virq[i], + (pq & XIVE_ESB_VAL_P) ? 'P' : '-', + (pq & XIVE_ESB_VAL_Q) ? 'Q' : '-', + xd->eoi_page); + seq_puts(m, "\n"); + } + } + return 0; +} + +void kvmppc_xive_debug_show_sources(struct seq_file *m, + struct kvmppc_xive_src_block *sb) +{ + int i; + + seq_puts(m, " LISN HW/CHIP TYPE PQ EISN CPU/PRIO\n"); + for (i = 0; i < KVMPPC_XICS_IRQ_PER_ICS; i++) { + struct kvmppc_xive_irq_state *state = &sb->irq_state[i]; + struct xive_irq_data *xd; + u64 pq; + u32 hw_num; + + if (!state->valid) + continue; + + kvmppc_xive_select_irq(state, &hw_num, &xd); + + pq = xive_vm_esb_load(xd, XIVE_ESB_GET); + + seq_printf(m, "%08x %08x/%02x", state->number, hw_num, + xd->src_chip); + if (state->lsi) + seq_printf(m, " %cLSI", state->asserted ? '^' : ' '); + else + seq_puts(m, " MSI"); + + seq_printf(m, " %s %c%c %08x % 4d/%d", + state->ipi_number == hw_num ? "IPI" : " PT", + pq & XIVE_ESB_VAL_P ? 'P' : '-', + pq & XIVE_ESB_VAL_Q ? 'Q' : '-', + state->eisn, state->act_server, + state->act_priority); + + seq_puts(m, "\n"); + } +} + +static int xive_debug_show(struct seq_file *m, void *private) +{ + struct kvmppc_xive *xive = m->private; + struct kvm *kvm = xive->kvm; + struct kvm_vcpu *vcpu; + u64 t_rm_h_xirr = 0; + u64 t_rm_h_ipoll = 0; + u64 t_rm_h_cppr = 0; + u64 t_rm_h_eoi = 0; + u64 t_rm_h_ipi = 0; + u64 t_vm_h_xirr = 0; + u64 t_vm_h_ipoll = 0; + u64 t_vm_h_cppr = 0; + u64 t_vm_h_eoi = 0; + u64 t_vm_h_ipi = 0; + unsigned long i; + + if (!kvm) + return 0; + + seq_puts(m, "=========\nVCPU state\n=========\n"); + + kvm_for_each_vcpu(i, vcpu, kvm) { + struct kvmppc_xive_vcpu *xc = vcpu->arch.xive_vcpu; + + if (!xc) + continue; + + seq_printf(m, "VCPU %d: VP:%#x/%02x\n" + " CPPR:%#x HWCPPR:%#x MFRR:%#x PEND:%#x h_xirr: R=%lld V=%lld\n", + xc->server_num, xc->vp_id, xc->vp_chip_id, + xc->cppr, xc->hw_cppr, + xc->mfrr, xc->pending, + xc->stat_rm_h_xirr, xc->stat_vm_h_xirr); + + kvmppc_xive_debug_show_queues(m, vcpu); + + t_rm_h_xirr += xc->stat_rm_h_xirr; + t_rm_h_ipoll += xc->stat_rm_h_ipoll; + t_rm_h_cppr += xc->stat_rm_h_cppr; + t_rm_h_eoi += xc->stat_rm_h_eoi; + t_rm_h_ipi += xc->stat_rm_h_ipi; + t_vm_h_xirr += xc->stat_vm_h_xirr; + t_vm_h_ipoll += xc->stat_vm_h_ipoll; + t_vm_h_cppr += xc->stat_vm_h_cppr; + t_vm_h_eoi += xc->stat_vm_h_eoi; + t_vm_h_ipi += xc->stat_vm_h_ipi; + } + + seq_puts(m, "Hcalls totals\n"); + seq_printf(m, " H_XIRR R=%10lld V=%10lld\n", t_rm_h_xirr, t_vm_h_xirr); + seq_printf(m, " H_IPOLL R=%10lld V=%10lld\n", t_rm_h_ipoll, t_vm_h_ipoll); + seq_printf(m, " H_CPPR R=%10lld V=%10lld\n", t_rm_h_cppr, t_vm_h_cppr); + seq_printf(m, " H_EOI R=%10lld V=%10lld\n", t_rm_h_eoi, t_vm_h_eoi); + seq_printf(m, " H_IPI R=%10lld V=%10lld\n", t_rm_h_ipi, t_vm_h_ipi); + + seq_puts(m, "=========\nSources\n=========\n"); + + for (i = 0; i <= xive->max_sbid; i++) { + struct kvmppc_xive_src_block *sb = xive->src_blocks[i]; + + if (sb) { + arch_spin_lock(&sb->lock); + kvmppc_xive_debug_show_sources(m, sb); + arch_spin_unlock(&sb->lock); + } + } + + return 0; +} + +DEFINE_SHOW_ATTRIBUTE(xive_debug); + +static void xive_debugfs_init(struct kvmppc_xive *xive) +{ + xive->dentry = debugfs_create_file("xive", S_IRUGO, xive->kvm->debugfs_dentry, + xive, &xive_debug_fops); + + pr_debug("%s: created\n", __func__); +} + +static void kvmppc_xive_init(struct kvm_device *dev) +{ + struct kvmppc_xive *xive = dev->private; + + /* Register some debug interfaces */ + xive_debugfs_init(xive); +} + +struct kvm_device_ops kvm_xive_ops = { + .name = "kvm-xive", + .create = kvmppc_xive_create, + .init = kvmppc_xive_init, + .release = kvmppc_xive_release, + .set_attr = xive_set_attr, + .get_attr = xive_get_attr, + .has_attr = xive_has_attr, +}; |