From 1f47ed294a2bd577d5ae43e6e28e1c9a3be4a833 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 13 Feb 2025 08:18:46 -0700 Subject: [PATCH 01/16] block: cleanup and fix batch completion adding conditions The conditions for whether or not a request is allowed adding to a completion batch are a bit hard to read, and they also have a few issues. One is that ioerror may indeed be a random value on passthrough, and it's being checked unconditionally of whether or not the given request is a passthrough request or not. Rewrite the conditions to be separate for easier reading, and only check ioerror for non-passthrough requests. This fixes an issue with bio unmapping on passthrough, where it fails getting added to a batch. This both leads to suboptimal performance, and may trigger a potential schedule-under-atomic condition for polled passthrough IO. Fixes: f794f3351f26 ("block: add support for blk_mq_end_request_batch()") Link: https://lore.kernel.org/r/20575f0a-656e-4bb3-9d82-dec6c7e3a35c@kernel.dk Signed-off-by: Jens Axboe --- include/linux/blk-mq.h | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 9ebb53f031cd..fa2a76cc2f73 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -861,12 +861,22 @@ static inline bool blk_mq_add_to_batch(struct request *req, void (*complete)(struct io_comp_batch *)) { /* - * blk_mq_end_request_batch() can't end request allocated from - * sched tags + * Check various conditions that exclude batch processing: + * 1) No batch container + * 2) Has scheduler data attached + * 3) Not a passthrough request and end_io set + * 4) Not a passthrough request and an ioerror */ - if (!iob || (req->rq_flags & RQF_SCHED_TAGS) || ioerror || - (req->end_io && !blk_rq_is_passthrough(req))) + if (!iob) return false; + if (req->rq_flags & RQF_SCHED_TAGS) + return false; + if (!blk_rq_is_passthrough(req)) { + if (req->end_io) + return false; + if (ioerror < 0) + return false; + } if (!iob->complete) iob->complete = complete; -- 2.51.0 From 80e648042e512d5a767da251d44132553fe04ae0 Mon Sep 17 00:00:00 2001 From: Jann Horn Date: Fri, 14 Feb 2025 02:39:50 +0100 Subject: [PATCH 02/16] partitions: mac: fix handling of bogus partition table Fix several issues in partition probing: - The bailout for a bad partoffset must use put_dev_sector(), since the preceding read_part_sector() succeeded. - If the partition table claims a silly sector size like 0xfff bytes (which results in partition table entries straddling sector boundaries), bail out instead of accessing out-of-bounds memory. - We must not assume that the partition table contains proper NUL termination - use strnlen() and strncmp() instead of strlen() and strcmp(). Cc: stable@vger.kernel.org Signed-off-by: Jann Horn Link: https://lore.kernel.org/r/20250214-partition-mac-v1-1-c1c626dffbd5@google.com Signed-off-by: Jens Axboe --- block/partitions/mac.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/block/partitions/mac.c b/block/partitions/mac.c index c80183156d68..b02530d98629 100644 --- a/block/partitions/mac.c +++ b/block/partitions/mac.c @@ -53,13 +53,25 @@ int mac_partition(struct parsed_partitions *state) } secsize = be16_to_cpu(md->block_size); put_dev_sector(sect); + + /* + * If the "block size" is not a power of 2, things get weird - we might + * end up with a partition straddling a sector boundary, so we wouldn't + * be able to read a partition entry with read_part_sector(). + * Real block sizes are probably (?) powers of two, so just require + * that. + */ + if (!is_power_of_2(secsize)) + return -1; datasize = round_down(secsize, 512); data = read_part_sector(state, datasize / 512, §); if (!data) return -1; partoffset = secsize % 512; - if (partoffset + sizeof(*part) > datasize) + if (partoffset + sizeof(*part) > datasize) { + put_dev_sector(sect); return -1; + } part = (struct mac_partition *) (data + partoffset); if (be16_to_cpu(part->signature) != MAC_PARTITION_MAGIC) { put_dev_sector(sect); @@ -112,8 +124,8 @@ int mac_partition(struct parsed_partitions *state) int i, l; goodness++; - l = strlen(part->name); - if (strcmp(part->name, "/") == 0) + l = strnlen(part->name, sizeof(part->name)); + if (strncmp(part->name, "/", sizeof(part->name)) == 0) goodness++; for (i = 0; i <= l - 4; ++i) { if (strncasecmp(part->name + i, "root", -- 2.51.0 From 43c70b104093c324b1a000762ce943d16ce788f9 Mon Sep 17 00:00:00 2001 From: Caleb Sander Mateos Date: Fri, 14 Feb 2025 12:36:36 -0700 Subject: [PATCH 03/16] block/merge: remove unnecessary min() with UINT_MAX In bvec_split_segs(), max_bytes is an unsigned, so it must be less than or equal to UINT_MAX. Remove the unnecessary min(). Prior to commit 67927d220150 ("block/merge: count bytes instead of sectors"), the min() was with UINT_MAX >> 9, so it did have an effect. Signed-off-by: Caleb Sander Mateos Link: https://lore.kernel.org/r/20250214193637.234702-1-csander@purestorage.com Signed-off-by: Jens Axboe --- block/blk-merge.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/block/blk-merge.c b/block/blk-merge.c index 15cd231d560c..39b738c0e4c9 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -270,7 +270,7 @@ static bool bvec_split_segs(const struct queue_limits *lim, const struct bio_vec *bv, unsigned *nsegs, unsigned *bytes, unsigned max_segs, unsigned max_bytes) { - unsigned max_len = min(max_bytes, UINT_MAX) - *bytes; + unsigned max_len = max_bytes - *bytes; unsigned len = min(bv->bv_len, max_len); unsigned total_len = 0; unsigned seg_size = 0; -- 2.51.0 From dd8b0582e25e36bba483c60338741c0ba5bc426c Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Mon, 17 Feb 2025 11:16:26 +0800 Subject: [PATCH 04/16] block: fix NULL pointer dereferenced within __blk_rq_map_sg The block layer internal flush request may not have bio attached, so the request iterator has to be initialized from valid req->bio, otherwise NULL pointer dereferenced is triggered. Cc: Christoph Hellwig Reported-and-tested-by: Cheyenne Wills Fixes: b7175e24d6ac ("block: add a dma mapping iterator") Signed-off-by: Ming Lei Reviewed-by: Christoph Hellwig Link: https://lore.kernel.org/r/20250217031626.461977-1-ming.lei@redhat.com Signed-off-by: Jens Axboe --- block/blk-merge.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/block/blk-merge.c b/block/blk-merge.c index 39b738c0e4c9..c7c85e10cf9c 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -556,11 +556,14 @@ int __blk_rq_map_sg(struct request_queue *q, struct request *rq, { struct req_iterator iter = { .bio = rq->bio, - .iter = rq->bio->bi_iter, }; struct phys_vec vec; int nsegs = 0; + /* the internal flush request may not have bio attached */ + if (iter.bio) + iter.iter = iter.bio->bi_iter; + while (blk_map_iter_next(rq, &iter, &vec)) { *last_sg = blk_next_sg(last_sg, sglist); sg_set_page(*last_sg, phys_to_page(vec.paddr), vec.len, -- 2.51.0 From fcd875445866a5219cf2be3101e276b21fc843f3 Mon Sep 17 00:00:00 2001 From: Christopher Lentocha Date: Tue, 18 Feb 2025 08:59:29 -0500 Subject: [PATCH 05/16] nvme-pci: quirk Acer FA100 for non-uniqueue identifiers In order for two Acer FA100 SSDs to work in one PC (in the case of myself, a Lenovo Legion T5 28IMB05), and not show one drive and not the other, and sometimes mix up what drive shows up (randomly), these two lines of code need to be added, and then both of the SSDs will show up and not conflict when booting off of one of them. If you boot up your computer with both SSDs installed without this patch, you may also randomly get into a kernel panic (if the initrd is not set up) or stuck in the initrd "/init" process, it is set up, however, if you do apply this patch, there should not be problems with booting or seeing both contents of the drive. Tested with the btrfs filesystem with a RAID configuration of having the root drive '/' combined to make two 256GB Acer FA100 SSDs become 512GB in total storage. Kernel Logs with patch applied (`dmesg -t | grep -i nvm`): ``` ... nvme 0000:04:00.0: platform quirk: setting simple suspend nvme nvme0: pci function 0000:04:00.0 nvme 0000:05:00.0: platform quirk: setting simple suspend nvme nvme1: pci function 0000:05:00.0 nvme nvme1: missing or invalid SUBNQN field. nvme nvme1: allocated 64 MiB host memory buffer. nvme nvme0: missing or invalid SUBNQN field. nvme nvme0: allocated 64 MiB host memory buffer. nvme nvme1: 8/0/0 default/read/poll queues nvme nvme1: Ignoring bogus Namespace Identifiers nvme nvme0: 8/0/0 default/read/poll queues nvme nvme0: Ignoring bogus Namespace Identifiers nvme0n1: p1 p2 ... ``` Kernel Logs with patch not applied (`dmesg -t | grep -i nvm`): ``` ... nvme 0000:04:00.0: platform quirk: setting simple suspend nvme nvme0: pci function 0000:04:00.0 nvme 0000:05:00.0: platform quirk: setting simple suspend nvme nvme1: pci function 0000:05:00.0 nvme nvme0: missing or invalid SUBNQN field. nvme nvme1: missing or invalid SUBNQN field. nvme nvme0: allocated 64 MiB host memory buffer. nvme nvme1: allocated 64 MiB host memory buffer. nvme nvme0: 8/0/0 default/read/poll queues nvme nvme1: 8/0/0 default/read/poll queues nvme nvme1: globally duplicate IDs for nsid 1 nvme nvme1: VID:DID 1dbe:5216 model:Acer SSD FA100 256GB firmware:1.Z.J.2X nvme0n1: p1 p2 ... ``` Signed-off-by: Christopher Lentocha Reviewed-by: Christoph Hellwig Signed-off-by: Keith Busch --- drivers/nvme/host/pci.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 9197a5b173fd..950289405ef2 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -3706,6 +3706,8 @@ static const struct pci_device_id nvme_id_table[] = { .driver_data = NVME_QUIRK_BOGUS_NID, }, { PCI_DEVICE(0x1cc1, 0x5350), /* ADATA XPG GAMMIX S50 */ .driver_data = NVME_QUIRK_BOGUS_NID, }, + { PCI_DEVICE(0x1dbe, 0x5216), /* Acer/INNOGRIT FA100/5216 NVMe SSD */ + .driver_data = NVME_QUIRK_BOGUS_NID, }, { PCI_DEVICE(0x1dbe, 0x5236), /* ADATA XPG GAMMIX S70 */ .driver_data = NVME_QUIRK_BOGUS_NID, }, { PCI_DEVICE(0x1e49, 0x0021), /* ZHITAI TiPro5000 NVMe SSD */ -- 2.51.0 From 84e009042d0f3dfe91bec60bcd208ee3f866cbcd Mon Sep 17 00:00:00 2001 From: Maurizio Lombardi Date: Mon, 17 Feb 2025 17:08:27 +0100 Subject: [PATCH 06/16] nvme-tcp: add basic support for the C2HTermReq PDU Previously, the NVMe/TCP host driver did not handle the C2HTermReq PDU, instead printing "unsupported pdu type (3)" when received. This patch adds support for processing the C2HTermReq PDU, allowing the driver to print the Fatal Error Status field. Example of output: nvme nvme4: Received C2HTermReq (FES = Invalid PDU Header Field) Signed-off-by: Maurizio Lombardi Reviewed-by: Sagi Grimberg Signed-off-by: Keith Busch --- drivers/nvme/host/tcp.c | 43 ++++++++++++++++++++++++++++++++++++++++ include/linux/nvme-tcp.h | 2 ++ 2 files changed, 45 insertions(+) diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c index 841238f38fdd..038b35238c26 100644 --- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -763,6 +763,40 @@ static int nvme_tcp_handle_r2t(struct nvme_tcp_queue *queue, return 0; } +static void nvme_tcp_handle_c2h_term(struct nvme_tcp_queue *queue, + struct nvme_tcp_term_pdu *pdu) +{ + u16 fes; + const char *msg; + u32 plen = le32_to_cpu(pdu->hdr.plen); + + static const char * const msg_table[] = { + [NVME_TCP_FES_INVALID_PDU_HDR] = "Invalid PDU Header Field", + [NVME_TCP_FES_PDU_SEQ_ERR] = "PDU Sequence Error", + [NVME_TCP_FES_HDR_DIGEST_ERR] = "Header Digest Error", + [NVME_TCP_FES_DATA_OUT_OF_RANGE] = "Data Transfer Out Of Range", + [NVME_TCP_FES_R2T_LIMIT_EXCEEDED] = "R2T Limit Exceeded", + [NVME_TCP_FES_UNSUPPORTED_PARAM] = "Unsupported Parameter", + }; + + if (plen < NVME_TCP_MIN_C2HTERM_PLEN || + plen > NVME_TCP_MAX_C2HTERM_PLEN) { + dev_err(queue->ctrl->ctrl.device, + "Received a malformed C2HTermReq PDU (plen = %u)\n", + plen); + return; + } + + fes = le16_to_cpu(pdu->fes); + if (fes && fes < ARRAY_SIZE(msg_table)) + msg = msg_table[fes]; + else + msg = "Unknown"; + + dev_err(queue->ctrl->ctrl.device, + "Received C2HTermReq (FES = %s)\n", msg); +} + static int nvme_tcp_recv_pdu(struct nvme_tcp_queue *queue, struct sk_buff *skb, unsigned int *offset, size_t *len) { @@ -784,6 +818,15 @@ static int nvme_tcp_recv_pdu(struct nvme_tcp_queue *queue, struct sk_buff *skb, return 0; hdr = queue->pdu; + if (unlikely(hdr->type == nvme_tcp_c2h_term)) { + /* + * C2HTermReq never includes Header or Data digests. + * Skip the checks. + */ + nvme_tcp_handle_c2h_term(queue, (void *)queue->pdu); + return -EINVAL; + } + if (queue->hdr_digest) { ret = nvme_tcp_verify_hdgst(queue, queue->pdu, hdr->hlen); if (unlikely(ret)) diff --git a/include/linux/nvme-tcp.h b/include/linux/nvme-tcp.h index e07e8978d691..e435250fcb4d 100644 --- a/include/linux/nvme-tcp.h +++ b/include/linux/nvme-tcp.h @@ -13,6 +13,8 @@ #define NVME_TCP_ADMIN_CCSZ SZ_8K #define NVME_TCP_DIGEST_LENGTH 4 #define NVME_TCP_MIN_MAXH2CDATA 4096 +#define NVME_TCP_MIN_C2HTERM_PLEN 24 +#define NVME_TCP_MAX_C2HTERM_PLEN 152 enum nvme_tcp_pfv { NVME_TCP_PFV_1_0 = 0x0, -- 2.51.0 From 4082326807072b71496501b6a0c55ffe8d5092a5 Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Fri, 7 Feb 2025 13:41:34 +0100 Subject: [PATCH 07/16] nvmet: Fix crash when a namespace is disabled The namespace percpu counter protects pending I/O, and we can only safely diable the namespace once the counter drop to zero. Otherwise we end up with a crash when running blktests/nvme/058 (eg for loop transport): [ 2352.930426] [ T53909] Oops: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN PTI [ 2352.930431] [ T53909] KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] [ 2352.930434] [ T53909] CPU: 3 UID: 0 PID: 53909 Comm: kworker/u16:5 Tainted: G W 6.13.0-rc6 #232 [ 2352.930438] [ T53909] Tainted: [W]=WARN [ 2352.930440] [ T53909] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-3.fc41 04/01/2014 [ 2352.930443] [ T53909] Workqueue: nvmet-wq nvme_loop_execute_work [nvme_loop] [ 2352.930449] [ T53909] RIP: 0010:blkcg_set_ioprio+0x44/0x180 as the queue is already torn down when calling submit_bio(); So we need to init the percpu counter in nvmet_ns_enable(), and wait for it to drop to zero in nvmet_ns_disable() to avoid having I/O pending after the namespace has been disabled. Fixes: 74d16965d7ac ("nvmet-loop: avoid using mutex in IO hotpath") Signed-off-by: Hannes Reinecke Reviewed-by: Nilay Shroff Reviewed-by: Sagi Grimberg Reviewed-by: Christoph Hellwig Reviewed-by: Chaitanya Kulkarni Tested-by: Shin'ichiro Kawasaki Signed-off-by: Keith Busch --- drivers/nvme/target/core.c | 40 ++++++++++++++++++-------------------- 1 file changed, 19 insertions(+), 21 deletions(-) diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c index cdc4a09a6e8a..2e741696f371 100644 --- a/drivers/nvme/target/core.c +++ b/drivers/nvme/target/core.c @@ -606,6 +606,9 @@ int nvmet_ns_enable(struct nvmet_ns *ns) goto out_dev_put; } + if (percpu_ref_init(&ns->ref, nvmet_destroy_namespace, 0, GFP_KERNEL)) + goto out_pr_exit; + nvmet_ns_changed(subsys, ns->nsid); ns->enabled = true; xa_set_mark(&subsys->namespaces, ns->nsid, NVMET_NS_ENABLED); @@ -613,6 +616,9 @@ int nvmet_ns_enable(struct nvmet_ns *ns) out_unlock: mutex_unlock(&subsys->lock); return ret; +out_pr_exit: + if (ns->pr.enable) + nvmet_pr_exit_ns(ns); out_dev_put: list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) pci_dev_put(radix_tree_delete(&ctrl->p2p_ns_map, ns->nsid)); @@ -638,6 +644,19 @@ void nvmet_ns_disable(struct nvmet_ns *ns) mutex_unlock(&subsys->lock); + /* + * Now that we removed the namespaces from the lookup list, we + * can kill the per_cpu ref and wait for any remaining references + * to be dropped, as well as a RCU grace period for anyone only + * using the namepace under rcu_read_lock(). Note that we can't + * use call_rcu here as we need to ensure the namespaces have + * been fully destroyed before unloading the module. + */ + percpu_ref_kill(&ns->ref); + synchronize_rcu(); + wait_for_completion(&ns->disable_done); + percpu_ref_exit(&ns->ref); + if (ns->pr.enable) nvmet_pr_exit_ns(ns); @@ -660,22 +679,6 @@ void nvmet_ns_free(struct nvmet_ns *ns) if (ns->nsid == subsys->max_nsid) subsys->max_nsid = nvmet_max_nsid(subsys); - mutex_unlock(&subsys->lock); - - /* - * Now that we removed the namespaces from the lookup list, we - * can kill the per_cpu ref and wait for any remaining references - * to be dropped, as well as a RCU grace period for anyone only - * using the namepace under rcu_read_lock(). Note that we can't - * use call_rcu here as we need to ensure the namespaces have - * been fully destroyed before unloading the module. - */ - percpu_ref_kill(&ns->ref); - synchronize_rcu(); - wait_for_completion(&ns->disable_done); - percpu_ref_exit(&ns->ref); - - mutex_lock(&subsys->lock); subsys->nr_namespaces--; mutex_unlock(&subsys->lock); @@ -705,9 +708,6 @@ struct nvmet_ns *nvmet_ns_alloc(struct nvmet_subsys *subsys, u32 nsid) ns->nsid = nsid; ns->subsys = subsys; - if (percpu_ref_init(&ns->ref, nvmet_destroy_namespace, 0, GFP_KERNEL)) - goto out_free; - if (ns->nsid > subsys->max_nsid) subsys->max_nsid = nsid; @@ -730,8 +730,6 @@ struct nvmet_ns *nvmet_ns_alloc(struct nvmet_subsys *subsys, u32 nsid) return ns; out_exit: subsys->max_nsid = nvmet_max_nsid(subsys); - percpu_ref_exit(&ns->ref); -out_free: kfree(ns); out_unlock: mutex_unlock(&subsys->lock); -- 2.51.0 From 3988ac1c67e6e84d2feb987d7b36d5791174b3da Mon Sep 17 00:00:00 2001 From: Ruozhu Li Date: Sun, 16 Feb 2025 20:49:56 +0800 Subject: [PATCH 08/16] nvmet-rdma: recheck queue state is LIVE in state lock in recv done The queue state checking in nvmet_rdma_recv_done is not in queue state lock.Queue state can transfer to LIVE in cm establish handler between state checking and state lock here, cause a silent drop of nvme connect cmd. Recheck queue state whether in LIVE state in state lock to prevent this issue. Signed-off-by: Ruozhu Li Reviewed-by: Sagi Grimberg Signed-off-by: Keith Busch --- drivers/nvme/target/rdma.c | 33 +++++++++++++++++++++++---------- 1 file changed, 23 insertions(+), 10 deletions(-) diff --git a/drivers/nvme/target/rdma.c b/drivers/nvme/target/rdma.c index 1afd93026f9b..2a4536ef6184 100644 --- a/drivers/nvme/target/rdma.c +++ b/drivers/nvme/target/rdma.c @@ -996,6 +996,27 @@ out_err: nvmet_req_complete(&cmd->req, status); } +static bool nvmet_rdma_recv_not_live(struct nvmet_rdma_queue *queue, + struct nvmet_rdma_rsp *rsp) +{ + unsigned long flags; + bool ret = true; + + spin_lock_irqsave(&queue->state_lock, flags); + /* + * recheck queue state is not live to prevent a race condition + * with RDMA_CM_EVENT_ESTABLISHED handler. + */ + if (queue->state == NVMET_RDMA_Q_LIVE) + ret = false; + else if (queue->state == NVMET_RDMA_Q_CONNECTING) + list_add_tail(&rsp->wait_list, &queue->rsp_wait_list); + else + nvmet_rdma_put_rsp(rsp); + spin_unlock_irqrestore(&queue->state_lock, flags); + return ret; +} + static void nvmet_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc) { struct nvmet_rdma_cmd *cmd = @@ -1038,17 +1059,9 @@ static void nvmet_rdma_recv_done(struct ib_cq *cq, struct ib_wc *wc) rsp->n_rdma = 0; rsp->invalidate_rkey = 0; - if (unlikely(queue->state != NVMET_RDMA_Q_LIVE)) { - unsigned long flags; - - spin_lock_irqsave(&queue->state_lock, flags); - if (queue->state == NVMET_RDMA_Q_CONNECTING) - list_add_tail(&rsp->wait_list, &queue->rsp_wait_list); - else - nvmet_rdma_put_rsp(rsp); - spin_unlock_irqrestore(&queue->state_lock, flags); + if (unlikely(queue->state != NVMET_RDMA_Q_LIVE) && + nvmet_rdma_recv_not_live(queue, rsp)) return; - } nvmet_rdma_handle_command(queue, rsp); } -- 2.51.0 From 68a5c91f01fc9f086567b260cced003ed9fdff3f Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Thu, 13 Feb 2025 15:52:28 +0900 Subject: [PATCH 09/16] nvmet: pci-epf: Correctly initialize CSTS when enabling the controller The function nvmet_pci_epf_poll_cc_work() sets the NVME_CSTS_RDY bit of the controller status register (CSTS) when nvmet_pci_epf_enable_ctrl() returns success. However, since this function can be called several times (e.g. if the host reboots), instead of setting the bit in ctrl->csts, initialize this field to only have NVME_CSTS_RDY set. Conversely, if nvmet_pci_epf_enable_ctrl() fails, make sure to clear all bits from ctrl->csts. To simplify nvmet_pci_epf_poll_cc_work(), initialize ctrl->csts to NVME_CSTS_RDY directly inside nvmet_pci_epf_enable_ctrl() and clear this field in that function as well in case of a failure. To be consistent, move clearing the NVME_CSTS_RDY bit from ctrl->csts when the controller is being disabled from nvmet_pci_epf_poll_cc_work() into nvmet_pci_epf_disable_ctrl(). Fixes: 0faa0fe6f90e ("nvmet: New NVMe PCI endpoint function target driver") Signed-off-by: Damien Le Moal Reviewed-by: Christoph Hellwig Reviewed-by: Sagi Grimberg Signed-off-by: Keith Busch --- drivers/nvme/target/pci-epf.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/drivers/nvme/target/pci-epf.c b/drivers/nvme/target/pci-epf.c index ac30b42cc622..efd4623fb002 100644 --- a/drivers/nvme/target/pci-epf.c +++ b/drivers/nvme/target/pci-epf.c @@ -1822,14 +1822,14 @@ static int nvmet_pci_epf_enable_ctrl(struct nvmet_pci_epf_ctrl *ctrl) if (ctrl->io_sqes < sizeof(struct nvme_command)) { dev_err(ctrl->dev, "Unsupported I/O SQES %zu (need %zu)\n", ctrl->io_sqes, sizeof(struct nvme_command)); - return -EINVAL; + goto err; } ctrl->io_cqes = 1UL << nvmet_cc_iocqes(ctrl->cc); if (ctrl->io_cqes < sizeof(struct nvme_completion)) { dev_err(ctrl->dev, "Unsupported I/O CQES %zu (need %zu)\n", ctrl->io_sqes, sizeof(struct nvme_completion)); - return -EINVAL; + goto err; } /* Create the admin queue. */ @@ -1844,7 +1844,7 @@ static int nvmet_pci_epf_enable_ctrl(struct nvmet_pci_epf_ctrl *ctrl) qsize, pci_addr, 0); if (status != NVME_SC_SUCCESS) { dev_err(ctrl->dev, "Failed to create admin completion queue\n"); - return -EINVAL; + goto err; } qsize = aqa & 0x00000fff; @@ -1854,17 +1854,22 @@ static int nvmet_pci_epf_enable_ctrl(struct nvmet_pci_epf_ctrl *ctrl) if (status != NVME_SC_SUCCESS) { dev_err(ctrl->dev, "Failed to create admin submission queue\n"); nvmet_pci_epf_delete_cq(ctrl->tctrl, 0); - return -EINVAL; + goto err; } ctrl->sq_ab = NVMET_PCI_EPF_SQ_AB; ctrl->irq_vector_threshold = NVMET_PCI_EPF_IV_THRESHOLD; ctrl->enabled = true; + ctrl->csts = NVME_CSTS_RDY; /* Start polling the controller SQs. */ schedule_delayed_work(&ctrl->poll_sqs, 0); return 0; + +err: + ctrl->csts = 0; + return -EINVAL; } static void nvmet_pci_epf_disable_ctrl(struct nvmet_pci_epf_ctrl *ctrl) @@ -1889,6 +1894,8 @@ static void nvmet_pci_epf_disable_ctrl(struct nvmet_pci_epf_ctrl *ctrl) /* Delete the admin queue last. */ nvmet_pci_epf_delete_sq(ctrl->tctrl, 0); nvmet_pci_epf_delete_cq(ctrl->tctrl, 0); + + ctrl->csts &= ~NVME_CSTS_RDY; } static void nvmet_pci_epf_poll_cc_work(struct work_struct *work) @@ -1909,13 +1916,10 @@ static void nvmet_pci_epf_poll_cc_work(struct work_struct *work) ret = nvmet_pci_epf_enable_ctrl(ctrl); if (ret) return; - ctrl->csts |= NVME_CSTS_RDY; } - if (!nvmet_cc_en(new_cc) && nvmet_cc_en(old_cc)) { + if (!nvmet_cc_en(new_cc) && nvmet_cc_en(old_cc)) nvmet_pci_epf_disable_ctrl(ctrl); - ctrl->csts &= ~NVME_CSTS_RDY; - } if (nvmet_cc_shn(new_cc) && !nvmet_cc_shn(old_cc)) { nvmet_pci_epf_disable_ctrl(ctrl); -- 2.51.0 From ffa35567632c0059e7f380ed155e26a07ec4153f Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Thu, 13 Feb 2025 15:52:29 +0900 Subject: [PATCH 10/16] nvmet: pci-epf: Do not uselessly write the CSTS register The function nvmet_pci_epf_poll_cc_work() will do nothing if there are no changes to the controller configuration (CC) register. However, even for such case, this function still calls nvmet_update_cc() and uselessly writes the CSTS register. Avoid this by simply rescheduling the poll_cc work if the CC register has not changed. Also reschedule the poll_cc work if the function nvmet_pci_epf_enable_ctrl() fails to allow the host the chance to try again enabling the controller. While at it, since there is no point in trying to handle the CC register as quickly as possible, change the poll_cc work scheduling interval to 10 ms (from 5ms), to avoid excessive read accesses to that register. Fixes: 0faa0fe6f90e ("nvmet: New NVMe PCI endpoint function target driver") Signed-off-by: Damien Le Moal Reviewed-by: Christoph Hellwig Reviewed-by: Sagi Grimberg Signed-off-by: Keith Busch --- drivers/nvme/target/pci-epf.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/nvme/target/pci-epf.c b/drivers/nvme/target/pci-epf.c index efd4623fb002..b646a8f468ea 100644 --- a/drivers/nvme/target/pci-epf.c +++ b/drivers/nvme/target/pci-epf.c @@ -46,7 +46,7 @@ static DEFINE_MUTEX(nvmet_pci_epf_ports_mutex); /* * BAR CC register and SQ polling intervals. */ -#define NVMET_PCI_EPF_CC_POLL_INTERVAL msecs_to_jiffies(5) +#define NVMET_PCI_EPF_CC_POLL_INTERVAL msecs_to_jiffies(10) #define NVMET_PCI_EPF_SQ_POLL_INTERVAL msecs_to_jiffies(5) #define NVMET_PCI_EPF_SQ_POLL_IDLE msecs_to_jiffies(5000) @@ -1910,12 +1910,15 @@ static void nvmet_pci_epf_poll_cc_work(struct work_struct *work) old_cc = ctrl->cc; new_cc = nvmet_pci_epf_bar_read32(ctrl, NVME_REG_CC); + if (new_cc == old_cc) + goto reschedule_work; + ctrl->cc = new_cc; if (nvmet_cc_en(new_cc) && !nvmet_cc_en(old_cc)) { ret = nvmet_pci_epf_enable_ctrl(ctrl); if (ret) - return; + goto reschedule_work; } if (!nvmet_cc_en(new_cc) && nvmet_cc_en(old_cc)) @@ -1932,6 +1935,7 @@ static void nvmet_pci_epf_poll_cc_work(struct work_struct *work) nvmet_update_cc(ctrl->tctrl, ctrl->cc); nvmet_pci_epf_bar_write32(ctrl, NVME_REG_CSTS, ctrl->csts); +reschedule_work: schedule_delayed_work(&ctrl->poll_cc, NVMET_PCI_EPF_CC_POLL_INTERVAL); } -- 2.51.0 From 01ef7ff7dd3cd8cc71af8d1d1496be853281a948 Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Thu, 13 Feb 2025 15:52:30 +0900 Subject: [PATCH 11/16] nvmet: pci-epf: Avoid RCU stalls under heavy workload The delayed work item function nvmet_pci_epf_poll_sqs_work() polls all submission queues and keeps running in a loop as long as commands are being submitted by the host. Depending on the preemption configuration of the kernel, under heavy command workload, this function can thus run for more than RCU_CPU_STALL_TIMEOUT seconds, leading to a RCU stall: rcu: INFO: rcu_sched self-detected stall on CPU rcu: 5-....: (20998 ticks this GP) idle=4244/1/0x4000000000000000 softirq=301/301 fqs=5132 rcu: (t=21000 jiffies g=-443 q=12 ncpus=8) CPU: 5 UID: 0 PID: 82 Comm: kworker/5:1 Not tainted 6.14.0-rc2 #1 Hardware name: Radxa ROCK 5B (DT) Workqueue: events nvmet_pci_epf_poll_sqs_work [nvmet_pci_epf] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : dw_edma_device_tx_status+0xb8/0x130 lr : dw_edma_device_tx_status+0x9c/0x130 sp : ffff800080b5bbb0 x29: ffff800080b5bbb0 x28: ffff0331c5c78400 x27: ffff0331c1cd1960 x26: ffff0331c0e39010 x25: ffff0331c20e4000 x24: ffff0331c20e4a90 x23: 0000000000000000 x22: 0000000000000001 x21: 00000000005aca33 x20: ffff800080b5bc30 x19: ffff0331c123e370 x18: 000000000ab29e62 x17: ffffb2a878c9c118 x16: ffff0335bde82040 x15: 0000000000000000 x14: 000000000000017b x13: 00000000ee601780 x12: 0000000000000018 x11: 0000000000000000 x10: 0000000000000001 x9 : 0000000000000040 x8 : 00000000ee601780 x7 : 0000000105c785c0 x6 : ffff0331c1027d80 x5 : 0000000001ee7ad6 x4 : ffff0335bdea16c0 x3 : ffff0331c123e438 x2 : 00000000005aca33 x1 : 0000000000000000 x0 : ffff0331c123e410 Call trace: dw_edma_device_tx_status+0xb8/0x130 (P) dma_sync_wait+0x60/0xbc nvmet_pci_epf_dma_transfer+0x128/0x264 [nvmet_pci_epf] nvmet_pci_epf_poll_sqs_work+0x2a0/0x2e0 [nvmet_pci_epf] process_one_work+0x144/0x390 worker_thread+0x27c/0x458 kthread+0xe8/0x19c ret_from_fork+0x10/0x20 The solution for this is simply to explicitly allow rescheduling using cond_resched(). However, since doing so for every loop of nvmet_pci_epf_poll_sqs_work() significantly degrades performance (for 4K random reads using 4 I/O queues, the maximum IOPS goes down from 137 KIOPS to 110 KIOPS), call cond_resched() every second to avoid the RCU stalls. Fixes: 0faa0fe6f90e ("nvmet: New NVMe PCI endpoint function target driver") Signed-off-by: Damien Le Moal Reviewed-by: Christoph Hellwig Reviewed-by: Sagi Grimberg Signed-off-by: Keith Busch --- drivers/nvme/target/pci-epf.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/nvme/target/pci-epf.c b/drivers/nvme/target/pci-epf.c index b646a8f468ea..565d2bd36dcd 100644 --- a/drivers/nvme/target/pci-epf.c +++ b/drivers/nvme/target/pci-epf.c @@ -1694,6 +1694,7 @@ static void nvmet_pci_epf_poll_sqs_work(struct work_struct *work) struct nvmet_pci_epf_ctrl *ctrl = container_of(work, struct nvmet_pci_epf_ctrl, poll_sqs.work); struct nvmet_pci_epf_queue *sq; + unsigned long limit = jiffies; unsigned long last = 0; int i, nr_sqs; @@ -1708,6 +1709,16 @@ static void nvmet_pci_epf_poll_sqs_work(struct work_struct *work) nr_sqs++; } + /* + * If we have been running for a while, reschedule to let other + * tasks run and to avoid RCU stalls. + */ + if (time_is_before_jiffies(limit + secs_to_jiffies(1))) { + cond_resched(); + limit = jiffies; + continue; + } + if (nr_sqs) { last = jiffies; continue; -- 2.51.0 From cd513e0434c3e736c549bc99bf7982658b25114d Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Thu, 13 Feb 2025 15:52:31 +0900 Subject: [PATCH 12/16] nvme: tcp: Fix compilation warning with W=1 When compiling with W=1, a warning result for the function nvme_tcp_set_queue_io_cpu(): host/tcp.c:1578: warning: Function parameter or struct member 'queue' not described in 'nvme_tcp_set_queue_io_cpu' host/tcp.c:1578: warning: expecting prototype for Track the number of queues assigned to each cpu using a global per(). Prototype was for nvme_tcp_set_queue_io_cpu() instead Avoid this warning by using the regular comment format for the function nvme_tcp_set_queue_io_cpu() instead of the kdoc comment format. Fixes: 32193789878c ("nvme-tcp: Fix I/O queue cpu spreading for multiple controllers") Signed-off-by: Damien Le Moal Reviewed-by: Christoph Hellwig Reviewed-by: Sagi Grimberg Signed-off-by: Keith Busch --- drivers/nvme/host/tcp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c index 038b35238c26..a7398e9e5f71 100644 --- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -1608,7 +1608,7 @@ static bool nvme_tcp_poll_queue(struct nvme_tcp_queue *queue) ctrl->io_queues[HCTX_TYPE_POLL]; } -/** +/* * Track the number of queues assigned to each cpu using a global per-cpu * counter and select the least used cpu from the mq_map. Our goal is to spread * different controllers I/O threads across different cpu cores. -- 2.51.0 From 578539e0969028f711c34d9a4565931edfe1d730 Mon Sep 17 00:00:00 2001 From: Caleb Sander Mateos Date: Fri, 24 Jan 2025 11:43:10 -0700 Subject: [PATCH 13/16] nvme-tcp: fix connect failure on receiving partial ICResp PDU nvme_tcp_init_connection() attempts to receive an ICResp PDU but only checks that the return value from recvmsg() is non-negative. If the sender closes the TCP connection or sends fewer than 128 bytes, this check will pass even though the full PDU wasn't received. Ensure the full ICResp PDU is received by checking that recvmsg() returns the expected 128 bytes. Additionally set the MSG_WAITALL flag for recvmsg(), as a sender could split the ICResp over multiple TCP frames. Without MSG_WAITALL, recvmsg() could return prematurely with only part of the PDU. Fixes: 3f2304f8c6d6 ("nvme-tcp: add NVMe over TCP host driver") Signed-off-by: Caleb Sander Mateos Reviewed-by: Sagi Grimberg Reviewed-by: Hannes Reinecke Signed-off-by: Keith Busch --- drivers/nvme/host/tcp.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/nvme/host/tcp.c b/drivers/nvme/host/tcp.c index a7398e9e5f71..8a9131c95a3d 100644 --- a/drivers/nvme/host/tcp.c +++ b/drivers/nvme/host/tcp.c @@ -1492,11 +1492,14 @@ static int nvme_tcp_init_connection(struct nvme_tcp_queue *queue) msg.msg_control = cbuf; msg.msg_controllen = sizeof(cbuf); } + msg.msg_flags = MSG_WAITALL; ret = kernel_recvmsg(queue->sock, &msg, &iov, 1, iov.iov_len, msg.msg_flags); - if (ret < 0) { + if (ret < sizeof(*icresp)) { pr_warn("queue %d: failed to receive icresp, error %d\n", nvme_tcp_queue_id(queue), ret); + if (ret >= 0) + ret = -ECONNRESET; goto free_icresp; } ret = -ENOTCONN; -- 2.51.0 From 487a3ea7b1b8ba2ca7d2c2bb3c3594dc360d6261 Mon Sep 17 00:00:00 2001 From: Caleb Sander Mateos Date: Thu, 13 Feb 2025 10:05:14 -0700 Subject: [PATCH 14/16] nvme/ioctl: add missing space in err message nvme_validate_passthru_nsid() logs an err message whose format string is split over 2 lines. There is a missing space between the two pieces, resulting in log lines like "... does not match nsid (1)of namespace". Add the missing space between ")" and "of". Also combine the format string pieces onto a single line to make the err message easier to grep. Fixes: e7d4b5493a2d ("nvme: factor out a nvme_validate_passthru_nsid helper") Signed-off-by: Caleb Sander Mateos Reviewed-by: Christoph Hellwig Signed-off-by: Keith Busch --- drivers/nvme/host/ioctl.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c index e8930146847a..b1b46c2713e1 100644 --- a/drivers/nvme/host/ioctl.c +++ b/drivers/nvme/host/ioctl.c @@ -283,8 +283,7 @@ static bool nvme_validate_passthru_nsid(struct nvme_ctrl *ctrl, { if (ns && nsid != ns->head->ns_id) { dev_err(ctrl->device, - "%s: nsid (%u) in cmd does not match nsid (%u)" - "of namespace\n", + "%s: nsid (%u) in cmd does not match nsid (%u) of namespace\n", current->comm, nsid, ns->head->ns_id); return false; } -- 2.51.0 From d422247d14a53fe825b1778edf104167d8fd8f3f Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Thu, 13 Feb 2025 15:49:59 +0900 Subject: [PATCH 15/16] nvme: Cleanup the definition of the controller config register fields Reorganized the enum used to define the fields of the contrller configuration (CC) register in include/linux/nvme.h to: 1) Group together all the values defined for each field. 2) Add the missing field masks definitions. 3) Add comments to describe the enum and each field. Signed-off-by: Damien Le Moal Reviewed-by: Chaitanya Kulkarni Reviewed-by: Christoph Hellwig Signed-off-by: Keith Busch --- include/linux/nvme.h | 40 +++++++++++++++++++++++++++++++++------- 1 file changed, 33 insertions(+), 7 deletions(-) diff --git a/include/linux/nvme.h b/include/linux/nvme.h index fe3b60818fdc..2dc05b1c3283 100644 --- a/include/linux/nvme.h +++ b/include/linux/nvme.h @@ -199,28 +199,54 @@ enum { #define NVME_NVM_IOSQES 6 #define NVME_NVM_IOCQES 4 +/* + * Controller Configuration (CC) register (Offset 14h) + */ enum { + /* Enable (EN): bit 0 */ NVME_CC_ENABLE = 1 << 0, NVME_CC_EN_SHIFT = 0, + + /* Bits 03:01 are reserved (NVMe Base Specification rev 2.1) */ + + /* I/O Command Set Selected (CSS): bits 06:04 */ NVME_CC_CSS_SHIFT = 4, - NVME_CC_MPS_SHIFT = 7, - NVME_CC_AMS_SHIFT = 11, - NVME_CC_SHN_SHIFT = 14, - NVME_CC_IOSQES_SHIFT = 16, - NVME_CC_IOCQES_SHIFT = 20, + NVME_CC_CSS_MASK = 7 << NVME_CC_CSS_SHIFT, NVME_CC_CSS_NVM = 0 << NVME_CC_CSS_SHIFT, NVME_CC_CSS_CSI = 6 << NVME_CC_CSS_SHIFT, - NVME_CC_CSS_MASK = 7 << NVME_CC_CSS_SHIFT, + + /* Memory Page Size (MPS): bits 10:07 */ + NVME_CC_MPS_SHIFT = 7, + NVME_CC_MPS_MASK = 0xf << NVME_CC_MPS_SHIFT, + + /* Arbitration Mechanism Selected (AMS): bits 13:11 */ + NVME_CC_AMS_SHIFT = 11, + NVME_CC_AMS_MASK = 7 << NVME_CC_AMS_SHIFT, NVME_CC_AMS_RR = 0 << NVME_CC_AMS_SHIFT, NVME_CC_AMS_WRRU = 1 << NVME_CC_AMS_SHIFT, NVME_CC_AMS_VS = 7 << NVME_CC_AMS_SHIFT, + + /* Shutdown Notification (SHN): bits 15:14 */ + NVME_CC_SHN_SHIFT = 14, + NVME_CC_SHN_MASK = 3 << NVME_CC_SHN_SHIFT, NVME_CC_SHN_NONE = 0 << NVME_CC_SHN_SHIFT, NVME_CC_SHN_NORMAL = 1 << NVME_CC_SHN_SHIFT, NVME_CC_SHN_ABRUPT = 2 << NVME_CC_SHN_SHIFT, - NVME_CC_SHN_MASK = 3 << NVME_CC_SHN_SHIFT, + + /* I/O Submission Queue Entry Size (IOSQES): bits 19:16 */ + NVME_CC_IOSQES_SHIFT = 16, + NVME_CC_IOSQES_MASK = 0xf << NVME_CC_IOSQES_SHIFT, NVME_CC_IOSQES = NVME_NVM_IOSQES << NVME_CC_IOSQES_SHIFT, + + /* I/O Completion Queue Entry Size (IOCQES): bits 23:20 */ + NVME_CC_IOCQES_SHIFT = 20, + NVME_CC_IOCQES_MASK = 0xf << NVME_CC_IOCQES_SHIFT, NVME_CC_IOCQES = NVME_NVM_IOCQES << NVME_CC_IOCQES_SHIFT, + + /* Controller Ready Independent of Media Enable (CRIME): bit 24 */ NVME_CC_CRIME = 1 << 24, + + /* Bits 25:31 are reserved (NVMe Base Specification rev 2.1) */ }; enum { -- 2.51.0 From 2ba8cf918f0d1873cd5430ae2cc3c41711a144d7 Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Thu, 13 Feb 2025 15:50:00 +0900 Subject: [PATCH 16/16] nvmet: Use enum definitions instead of hardcoded values Change the definition of the inline functions nvmet_cc_en(), nvmet_cc_css(), nvmet_cc_mps(), nvmet_cc_ams(), nvmet_cc_shn(), nvmet_cc_iosqes(), and nvmet_cc_iocqes() to use the enum difinitions in include/linux/nvme.h instead of hardcoded values. Signed-off-by: Damien Le Moal Reviewed-by: Chaitanya Kulkarni Reviewed-by: Christoph Hellwig Signed-off-by: Keith Busch --- drivers/nvme/target/nvmet.h | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h index 4be8d22d2d8d..d2c1233981e1 100644 --- a/drivers/nvme/target/nvmet.h +++ b/drivers/nvme/target/nvmet.h @@ -784,37 +784,37 @@ u16 nvmet_report_invalid_opcode(struct nvmet_req *req); static inline bool nvmet_cc_en(u32 cc) { - return (cc >> NVME_CC_EN_SHIFT) & 0x1; + return (cc & NVME_CC_ENABLE) >> NVME_CC_EN_SHIFT; } static inline u8 nvmet_cc_css(u32 cc) { - return (cc >> NVME_CC_CSS_SHIFT) & 0x7; + return (cc & NVME_CC_CSS_MASK) >> NVME_CC_CSS_SHIFT; } static inline u8 nvmet_cc_mps(u32 cc) { - return (cc >> NVME_CC_MPS_SHIFT) & 0xf; + return (cc & NVME_CC_MPS_MASK) >> NVME_CC_MPS_SHIFT; } static inline u8 nvmet_cc_ams(u32 cc) { - return (cc >> NVME_CC_AMS_SHIFT) & 0x7; + return (cc & NVME_CC_AMS_MASK) >> NVME_CC_AMS_SHIFT; } static inline u8 nvmet_cc_shn(u32 cc) { - return (cc >> NVME_CC_SHN_SHIFT) & 0x3; + return (cc & NVME_CC_SHN_MASK) >> NVME_CC_SHN_SHIFT; } static inline u8 nvmet_cc_iosqes(u32 cc) { - return (cc >> NVME_CC_IOSQES_SHIFT) & 0xf; + return (cc & NVME_CC_IOSQES_MASK) >> NVME_CC_IOSQES_SHIFT; } static inline u8 nvmet_cc_iocqes(u32 cc) { - return (cc >> NVME_CC_IOCQES_SHIFT) & 0xf; + return (cc & NVME_CC_IOCQES_MASK) >> NVME_CC_IOCQES_SHIFT; } /* Convert a 32-bit number to a 16-bit 0's based number */ -- 2.51.0