diff options
author | Jakub Kicinski <kuba@kernel.org> | 2024-03-22 02:14:13 +0300 |
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committer | Jakub Kicinski <kuba@kernel.org> | 2024-03-22 02:15:08 +0300 |
commit | 537c2e91d3549e5d6020bb0576cf9b54a845255f (patch) | |
tree | c09e8a1b7d733cde19b0c72678c28fb2bc97ff6b /arch/arm64/kvm/vgic/vgic-its.c | |
parent | 237bb5f7f7f55ec5f773469a974c61a49c298625 (diff) | |
parent | cba9ffdb9913dfe6be29f049ce920ce451ce7cc4 (diff) | |
download | linux-537c2e91d3549e5d6020bb0576cf9b54a845255f.tar.xz |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'arch/arm64/kvm/vgic/vgic-its.c')
-rw-r--r-- | arch/arm64/kvm/vgic/vgic-its.c | 63 |
1 files changed, 40 insertions, 23 deletions
diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c index 28a93074eca1..e85a495ada9c 100644 --- a/arch/arm64/kvm/vgic/vgic-its.c +++ b/arch/arm64/kvm/vgic/vgic-its.c @@ -52,7 +52,12 @@ static struct vgic_irq *vgic_add_lpi(struct kvm *kvm, u32 intid, if (!irq) return ERR_PTR(-ENOMEM); - INIT_LIST_HEAD(&irq->lpi_list); + ret = xa_reserve_irq(&dist->lpi_xa, intid, GFP_KERNEL_ACCOUNT); + if (ret) { + kfree(irq); + return ERR_PTR(ret); + } + INIT_LIST_HEAD(&irq->ap_list); raw_spin_lock_init(&irq->irq_lock); @@ -68,30 +73,30 @@ static struct vgic_irq *vgic_add_lpi(struct kvm *kvm, u32 intid, * There could be a race with another vgic_add_lpi(), so we need to * check that we don't add a second list entry with the same LPI. */ - list_for_each_entry(oldirq, &dist->lpi_list_head, lpi_list) { - if (oldirq->intid != intid) - continue; - + oldirq = xa_load(&dist->lpi_xa, intid); + if (vgic_try_get_irq_kref(oldirq)) { /* Someone was faster with adding this LPI, lets use that. */ kfree(irq); irq = oldirq; - /* - * This increases the refcount, the caller is expected to - * call vgic_put_irq() on the returned pointer once it's - * finished with the IRQ. - */ - vgic_get_irq_kref(irq); + goto out_unlock; + } + ret = xa_err(xa_store(&dist->lpi_xa, intid, irq, 0)); + if (ret) { + xa_release(&dist->lpi_xa, intid); + kfree(irq); goto out_unlock; } - list_add_tail(&irq->lpi_list, &dist->lpi_list_head); - dist->lpi_list_count++; + atomic_inc(&dist->lpi_count); out_unlock: raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags); + if (ret) + return ERR_PTR(ret); + /* * We "cache" the configuration table entries in our struct vgic_irq's. * However we only have those structs for mapped IRQs, so we read in @@ -158,7 +163,7 @@ struct vgic_translation_cache_entry { * @cte_esz: collection table entry size * @dte_esz: device table entry size * @ite_esz: interrupt translation table entry size - * @save tables: save the ITS tables into guest RAM + * @save_tables: save the ITS tables into guest RAM * @restore_tables: restore the ITS internal structs from tables * stored in guest RAM * @commit: initialize the registers which expose the ABI settings, @@ -311,6 +316,8 @@ static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq, return 0; } +#define GIC_LPI_MAX_INTID ((1 << INTERRUPT_ID_BITS_ITS) - 1) + /* * Create a snapshot of the current LPIs targeting @vcpu, so that we can * enumerate those LPIs without holding any lock. @@ -319,6 +326,7 @@ static int update_lpi_config(struct kvm *kvm, struct vgic_irq *irq, int vgic_copy_lpi_list(struct kvm *kvm, struct kvm_vcpu *vcpu, u32 **intid_ptr) { struct vgic_dist *dist = &kvm->arch.vgic; + XA_STATE(xas, &dist->lpi_xa, GIC_LPI_OFFSET); struct vgic_irq *irq; unsigned long flags; u32 *intids; @@ -331,13 +339,15 @@ int vgic_copy_lpi_list(struct kvm *kvm, struct kvm_vcpu *vcpu, u32 **intid_ptr) * command). If coming from another path (such as enabling LPIs), * we must be careful not to overrun the array. */ - irq_count = READ_ONCE(dist->lpi_list_count); + irq_count = atomic_read(&dist->lpi_count); intids = kmalloc_array(irq_count, sizeof(intids[0]), GFP_KERNEL_ACCOUNT); if (!intids) return -ENOMEM; raw_spin_lock_irqsave(&dist->lpi_list_lock, flags); - list_for_each_entry(irq, &dist->lpi_list_head, lpi_list) { + rcu_read_lock(); + + xas_for_each(&xas, irq, GIC_LPI_MAX_INTID) { if (i == irq_count) break; /* We don't need to "get" the IRQ, as we hold the list lock. */ @@ -345,6 +355,8 @@ int vgic_copy_lpi_list(struct kvm *kvm, struct kvm_vcpu *vcpu, u32 **intid_ptr) continue; intids[i++] = irq->intid; } + + rcu_read_unlock(); raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags); *intid_ptr = intids; @@ -595,8 +607,8 @@ static struct vgic_irq *vgic_its_check_cache(struct kvm *kvm, phys_addr_t db, raw_spin_lock_irqsave(&dist->lpi_list_lock, flags); irq = __vgic_its_check_cache(dist, db, devid, eventid); - if (irq) - vgic_get_irq_kref(irq); + if (!vgic_try_get_irq_kref(irq)) + irq = NULL; raw_spin_unlock_irqrestore(&dist->lpi_list_lock, flags); @@ -640,8 +652,13 @@ static void vgic_its_cache_translation(struct kvm *kvm, struct vgic_its *its, * was in the cache, and increment it on the new interrupt. */ if (cte->irq) - __vgic_put_lpi_locked(kvm, cte->irq); + vgic_put_irq(kvm, cte->irq); + /* + * The irq refcount is guaranteed to be nonzero while holding the + * its_lock, as the ITE (and the reference it holds) cannot be freed. + */ + lockdep_assert_held(&its->its_lock); vgic_get_irq_kref(irq); cte->db = db; @@ -672,7 +689,7 @@ void vgic_its_invalidate_cache(struct kvm *kvm) if (!cte->irq) break; - __vgic_put_lpi_locked(kvm, cte->irq); + vgic_put_irq(kvm, cte->irq); cte->irq = NULL; } @@ -1345,8 +1362,8 @@ static int vgic_its_cmd_handle_inv(struct kvm *kvm, struct vgic_its *its, } /** - * vgic_its_invall - invalidate all LPIs targetting a given vcpu - * @vcpu: the vcpu for which the RD is targetted by an invalidation + * vgic_its_invall - invalidate all LPIs targeting a given vcpu + * @vcpu: the vcpu for which the RD is targeted by an invalidation * * Contrary to the INVALL command, this targets a RD instead of a * collection, and we don't need to hold the its_lock, since no ITS is @@ -2144,7 +2161,7 @@ static u32 compute_next_eventid_offset(struct list_head *h, struct its_ite *ite) } /** - * entry_fn_t - Callback called on a table entry restore path + * typedef entry_fn_t - Callback called on a table entry restore path * @its: its handle * @id: id of the entry * @entry: pointer to the entry |