[PATCH v3 0/2] hw/nvme: add irqfd support

[Klaus Jensen <its@irrelevant.dk>]

From: Klaus Jensen <k.jensen@samsung.com>

This is a re-spin of Jinhao's irqfd support series that fixes msix
vector masking/unmasking to work correctly.

I kept being bugged out about that msi route not getting updated, so I
hit the code into submission with a hammer.

I finally noticed the core issue:

  1. The vector notifiers was never set because msix is not enabled at
     the point where nvme_init_pci() is called.

     Move this call to nvme_start_ctrl().

Since the unmask callback was suddenly getting called now, another fix
was needed:

  2. Call kvm_irqchip_add_irqfd_notifier_gsi() in the unmask handler -
     not in nvme_init_irq_notifier(). The vectors may potentially be
     masked/unmasked and shall cause a pair of add_irqfd and
     remove_irqfd calls. Removing it from nvme_init_irq_notifier() makes
     sure we do not try to double add.

Now it does what it is supposed to; no hacks required :)

Jinhao Fan (2):
  hw/nvme: support irq(de)assertion with eventfd
  hw/nvme: use KVM irqfd when available

 hw/nvme/ctrl.c       | 261 ++++++++++++++++++++++++++++++++++++++++---
 hw/nvme/nvme.h       |   6 +
 hw/nvme/trace-events |   3 +
 3 files changed, 253 insertions(+), 17 deletions(-)

-- 
2.37.2