nvme: disable Write Zeroes for qemu controllers

Qemu started out with a broken implementation of Write Zeroes written
by yours truly.  Disable Write Zeroes on qemu for now, eventually
we need to go back and make all the qemu quirks version specific,
but that is left for another time.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/nvme/host/core.c

@@ -1531,7 +1531,8 @@ static inline void nvme_config_write_zeroes(struct nvme_ns *ns)
 	u32 max_sectors;
 	unsigned short bs = 1 << ns->lba_shift;
 
-	if (!(ns->ctrl->oncs & NVME_CTRL_ONCS_WRITE_ZEROES))
+	if (!(ns->ctrl->oncs & NVME_CTRL_ONCS_WRITE_ZEROES) ||
+	    (ns->ctrl->quirks & NVME_QUIRK_DISABLE_WRITE_ZEROES))
 		return;
 	/*
 	 * Even though NVMe spec explicitly states that MDTS is not

drivers/nvme/host/nvme.h

@@ -87,6 +87,11 @@ enum nvme_quirks {
 	 * Ignore device provided subnqn.
 	 */
 	NVME_QUIRK_IGNORE_DEV_SUBNQN		= (1 << 8),
+
+	/*
+	 * Broken Write Zeroes.
+	 */
+	NVME_QUIRK_DISABLE_WRITE_ZEROES		= (1 << 9),
 };
 
 /*

drivers/nvme/host/pci.c

@@ -2975,7 +2975,8 @@ static const struct pci_device_id nvme_id_table[] = {
 	{ PCI_VDEVICE(INTEL, 0xf1a6),	/* Intel 760p/Pro 7600p */
 		.driver_data = NVME_QUIRK_IGNORE_DEV_SUBNQN, },
 	{ PCI_VDEVICE(INTEL, 0x5845),	/* Qemu emulated controller */
-		.driver_data = NVME_QUIRK_IDENTIFY_CNS, },
+		.driver_data = NVME_QUIRK_IDENTIFY_CNS |
+				NVME_QUIRK_DISABLE_WRITE_ZEROES, },
 	{ PCI_DEVICE(0x1bb1, 0x0100),   /* Seagate Nytro Flash Storage */
 		.driver_data = NVME_QUIRK_DELAY_BEFORE_CHK_RDY, },
 	{ PCI_DEVICE(0x1c58, 0x0003),	/* HGST adapter */