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 ae04bdce560a1ab2d9ba5c66d4ca53b7cb59d412..7993acdfd3185f11614d5d90582a89451e9defa4 100644 (file)
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1888,6 +1888,7 @@ 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;
        }