nvme-pci: clean up CMBMSC when registering CMB fails

[ Upstream commit 6a3572e10f740acd48e2713ef37e92186a3ce5e8 ]

CMB decoding should get disabled when the CMB block isn't successfully
registered to P2P DMA subsystem.

Clean up the CMBMSC register in this error handling codepath to disable
CMB decoding (and CMBLOC/CMBSZ registers).

Signed-off-by: Icenowy Zheng <uwu@icenowy.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index a36ec6df6624b8cf59c4efce6fd314ff2d789fc4..3cc00d5a10065998f447151dd86eb8807c5ea7cc 100644 (file)
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1871,6 +1871,7 @@ static void nvme_map_cmb(struct nvme_dev *dev)
        if (pci_p2pdma_add_resource(pdev, bar, size, offset)) {
                dev_warn(dev->ctrl.device,
                         "failed to register the CMB\n");
+               hi_lo_writeq(0, dev->bar + NVME_REG_CMBMSC);
                return;
        }