nvme: add command id quirk for apple controllers

Some apple controllers use the command id as an index to implementation
specific data structures and will fail if the value is out of bounds.
The nvme driver's recently introduced command sequence number breaks
this controller.

Provide a quirk so these spec incompliant controllers can function as
before. The driver will not have the ability to detect bad completions
when this quirk is used, but we weren't previously checking this anyway.

The quirk bit was selected so that it can readily apply to stable.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=214509
Cc: Sven Peter <sven@svenpeter.dev>
Reported-by: Orlando Chamberlain <redecorating@protonmail.com>
Reported-by: Aditya Garg <gargaditya08@live.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Tested-by: Sven Peter <sven@svenpeter.dev>
Link: https://lore.kernel.org/r/20210927154306.387437-1-kbusch@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/nvme/host/core.c

@@ -978,6 +978,7 @@ EXPORT_SYMBOL_GPL(nvme_cleanup_cmd);
 blk_status_t nvme_setup_cmd(struct nvme_ns *ns, struct request *req)
 {
 	struct nvme_command *cmd = nvme_req(req)->cmd;
+	struct nvme_ctrl *ctrl = nvme_req(req)->ctrl;
 	blk_status_t ret = BLK_STS_OK;
 
 	if (!(req->rq_flags & RQF_DONTPREP)) {
@@ -1026,7 +1027,8 @@ blk_status_t nvme_setup_cmd(struct nvme_ns *ns, struct request *req)
 		return BLK_STS_IOERR;
 	}
 
-	nvme_req(req)->genctr++;
+	if (!(ctrl->quirks & NVME_QUIRK_SKIP_CID_GEN))
+		nvme_req(req)->genctr++;
 	cmd->common.command_id = nvme_cid(req);
 	trace_nvme_setup_cmd(req, cmd);
 	return ret;

drivers/nvme/host/nvme.h

@@ -138,6 +138,12 @@ enum nvme_quirks {
 	 * 48 bits.
 	 */
 	NVME_QUIRK_DMA_ADDRESS_BITS_48		= (1 << 16),
+
+	/*
+	 * The controller requires the command_id value be be limited, so skip
+	 * encoding the generation sequence number.
+	 */
+	NVME_QUIRK_SKIP_CID_GEN			= (1 << 17),
 };
 
 /*

drivers/nvme/host/pci.c

@@ -3369,7 +3369,8 @@ static const struct pci_device_id nvme_id_table[] = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_APPLE, 0x2005),
 		.driver_data = NVME_QUIRK_SINGLE_VECTOR |
 				NVME_QUIRK_128_BYTES_SQES |
-				NVME_QUIRK_SHARED_TAGS },
+				NVME_QUIRK_SHARED_TAGS |
+				NVME_QUIRK_SKIP_CID_GEN },
 
 	{ PCI_DEVICE_CLASS(PCI_CLASS_STORAGE_EXPRESS, 0xffffff) },
 	{ 0, }