[PATCH v18 2/2] nvmet: support reservation feature
Dmitry Bogdanov
d.bogdanov at yadro.com
Thu Oct 24 05:01:20 PDT 2024
On Thu, Oct 24, 2024 at 10:52:00AM +0800, Guixin Liu wrote:
> This patch implements the reservation feature, including:
> 1. reservation register(register, unregister and replace).
> 2. reservation acquire(acquire, preempt, preempt and abort).
> 3. reservation release(release and clear).
> 4. reservation report.
> 5. set feature and get feature of reservation notify mask.
> 6. get log page of reservation event.
>
> Not supported:
> 1. persistent reservation through power loss.
>
> Test cases:
> Use nvme-cli and fio to test all implemented sub features:
> 1. use nvme resv-register to register host a registrant or
> unregister or replace a new key.
> 2. use nvme resv-acquire to set host to the holder, and use fio
> to send read and write io in all reservation type. And also
> test preempt and "preempt and abort".
> 3. use nvme resv-report to show all registrants and reservation
> status.
> 4. use nvme resv-release to release all registrants.
> 5. use nvme get-log to get events generated by the preceding
> operations.
>
> In addition, make reservation configurable, one can set ns to
> support reservation before enable ns. The default of resv_enable
> is false.
>
> Signed-off-by: Guixin Liu <kanie at linux.alibaba.com>
> Reviewed-by: Dmitry Bogdanov <d.bogdanov at yadro.com>
> Reviewed-by: Christoph Hellwig <hch at lst.de>
> Tested-by: Chaitanya Kulkarni <kch at nvidia.com>
> Reviewed-by: Chaitanya Kulkarni <kch at nvidia.com>
> ---
> drivers/nvme/target/Makefile | 2 +-
> drivers/nvme/target/admin-cmd.c | 24 +-
> drivers/nvme/target/configfs.c | 27 +
> drivers/nvme/target/core.c | 58 +-
> drivers/nvme/target/fabrics-cmd.c | 4 +-
> drivers/nvme/target/nvmet.h | 66 +-
> drivers/nvme/target/pr.c | 1163 +++++++++++++++++++++++++++++
> 7 files changed, 1332 insertions(+), 12 deletions(-)
> create mode 100644 drivers/nvme/target/pr.c
>
> diff --git a/drivers/nvme/target/Makefile b/drivers/nvme/target/Makefile
> index c402c44350b2..f2b025bbe10c 100644
> --- a/drivers/nvme/target/Makefile
> +++ b/drivers/nvme/target/Makefile
> @@ -10,7 +10,7 @@ obj-$(CONFIG_NVME_TARGET_FCLOOP) += nvme-fcloop.o
> obj-$(CONFIG_NVME_TARGET_TCP) += nvmet-tcp.o
>
> nvmet-y += core.o configfs.o admin-cmd.o fabrics-cmd.o \
> - discovery.o io-cmd-file.o io-cmd-bdev.o
> + discovery.o io-cmd-file.o io-cmd-bdev.o pr.o
> nvmet-$(CONFIG_NVME_TARGET_DEBUGFS) += debugfs.o
> nvmet-$(CONFIG_NVME_TARGET_PASSTHRU) += passthru.o
> nvmet-$(CONFIG_BLK_DEV_ZONED) += zns.o
> diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
> index 081f0473cd9e..19428745c795 100644
> --- a/drivers/nvme/target/admin-cmd.c
> +++ b/drivers/nvme/target/admin-cmd.c
> @@ -176,6 +176,10 @@ static void nvmet_get_cmd_effects_nvm(struct nvme_effects_log *log)
> log->iocs[nvme_cmd_read] =
> log->iocs[nvme_cmd_flush] =
> log->iocs[nvme_cmd_dsm] =
> + log->iocs[nvme_cmd_resv_acquire] =
> + log->iocs[nvme_cmd_resv_register] =
> + log->iocs[nvme_cmd_resv_release] =
> + log->iocs[nvme_cmd_resv_report] =
> cpu_to_le32(NVME_CMD_EFFECTS_CSUPP);
> log->iocs[nvme_cmd_write] =
> log->iocs[nvme_cmd_write_zeroes] =
> @@ -340,6 +344,8 @@ static void nvmet_execute_get_log_page(struct nvmet_req *req)
> return nvmet_execute_get_log_cmd_effects_ns(req);
> case NVME_LOG_ANA:
> return nvmet_execute_get_log_page_ana(req);
> + case NVME_LOG_RESERVATION:
> + return nvmet_execute_get_log_page_resv(req);
> }
> pr_debug("unhandled lid %d on qid %d\n",
> req->cmd->get_log_page.lid, req->sq->qid);
> @@ -433,7 +439,8 @@ static void nvmet_execute_identify_ctrl(struct nvmet_req *req)
> id->nn = cpu_to_le32(NVMET_MAX_NAMESPACES);
> id->mnan = cpu_to_le32(NVMET_MAX_NAMESPACES);
> id->oncs = cpu_to_le16(NVME_CTRL_ONCS_DSM |
> - NVME_CTRL_ONCS_WRITE_ZEROES);
> + NVME_CTRL_ONCS_WRITE_ZEROES |
> + NVME_CTRL_ONCS_RESERVATIONS);
>
> /* XXX: don't report vwc if the underlying device is write through */
> id->vwc = NVME_CTRL_VWC_PRESENT;
> @@ -551,6 +558,15 @@ static void nvmet_execute_identify_ns(struct nvmet_req *req)
> id->nmic = NVME_NS_NMIC_SHARED;
> id->anagrpid = cpu_to_le32(req->ns->anagrpid);
>
> + if (req->ns->pr.enable)
> + id->rescap = NVME_PR_SUPPORT_WRITE_EXCLUSIVE |
> + NVME_PR_SUPPORT_EXCLUSIVE_ACCESS |
> + NVME_PR_SUPPORT_WRITE_EXCLUSIVE_REG_ONLY |
> + NVME_PR_SUPPORT_EXCLUSIVE_ACCESS_REG_ONLY |
> + NVME_PR_SUPPORT_WRITE_EXCLUSIVE_ALL_REGS |
> + NVME_PR_SUPPORT_EXCLUSIVE_ACCESS_ALL_REGS |
> + NVME_PR_SUPPORT_IEKEY_VER_1_3_DEF;
> +
> memcpy(&id->nguid, &req->ns->nguid, sizeof(id->nguid));
>
> id->lbaf[0].ds = req->ns->blksize_shift;
> @@ -861,6 +877,9 @@ void nvmet_execute_set_features(struct nvmet_req *req)
> case NVME_FEAT_WRITE_PROTECT:
> status = nvmet_set_feat_write_protect(req);
> break;
> + case NVME_FEAT_RESV_MASK:
> + status = nvmet_set_feat_resv_notif_mask(req, cdw11);
> + break;
> default:
> req->error_loc = offsetof(struct nvme_common_command, cdw10);
> status = NVME_SC_INVALID_FIELD | NVME_STATUS_DNR;
> @@ -959,6 +978,9 @@ void nvmet_execute_get_features(struct nvmet_req *req)
> case NVME_FEAT_WRITE_PROTECT:
> status = nvmet_get_feat_write_protect(req);
> break;
> + case NVME_FEAT_RESV_MASK:
> + status = nvmet_get_feat_resv_notif_mask(req);
> + break;
> default:
> req->error_loc =
> offsetof(struct nvme_common_command, cdw10);
> diff --git a/drivers/nvme/target/configfs.c b/drivers/nvme/target/configfs.c
> index 685e89b35d33..eeee9e9b854c 100644
> --- a/drivers/nvme/target/configfs.c
> +++ b/drivers/nvme/target/configfs.c
> @@ -769,6 +769,32 @@ static ssize_t nvmet_ns_revalidate_size_store(struct config_item *item,
>
> CONFIGFS_ATTR_WO(nvmet_ns_, revalidate_size);
>
> +static ssize_t nvmet_ns_resv_enable_show(struct config_item *item, char *page)
> +{
> + return sysfs_emit(page, "%d\n", to_nvmet_ns(item)->pr.enable);
> +}
> +
> +static ssize_t nvmet_ns_resv_enable_store(struct config_item *item,
> + const char *page, size_t count)
> +{
> + struct nvmet_ns *ns = to_nvmet_ns(item);
> + bool val;
> +
> + if (kstrtobool(page, &val))
> + return -EINVAL;
> +
> + mutex_lock(&ns->subsys->lock);
> + if (ns->enabled) {
> + pr_err("the ns:%d is already enabled.\n", ns->nsid);
> + mutex_unlock(&ns->subsys->lock);
> + return -EINVAL;
> + }
> + ns->pr.enable = val;
> + mutex_unlock(&ns->subsys->lock);
> + return count;
> +}
> +CONFIGFS_ATTR(nvmet_ns_, resv_enable);
> +
> static struct configfs_attribute *nvmet_ns_attrs[] = {
> &nvmet_ns_attr_device_path,
> &nvmet_ns_attr_device_nguid,
> @@ -777,6 +803,7 @@ static struct configfs_attribute *nvmet_ns_attrs[] = {
> &nvmet_ns_attr_enable,
> &nvmet_ns_attr_buffered_io,
> &nvmet_ns_attr_revalidate_size,
> + &nvmet_ns_attr_resv_enable,
> #ifdef CONFIG_PCI_P2PDMA
> &nvmet_ns_attr_p2pmem,
> #endif
> diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
> index ed2424f8a396..a2af7a9bc3b9 100644
> --- a/drivers/nvme/target/core.c
> +++ b/drivers/nvme/target/core.c
> @@ -611,6 +611,12 @@ int nvmet_ns_enable(struct nvmet_ns *ns)
> if (ret)
> goto out_restore_subsys_maxnsid;
>
> + if (ns->pr.enable) {
> + ret = nvmet_pr_init_ns(ns);
> + if (ret)
> + goto out_remove_from_subsys;
> + }
> +
> subsys->nr_namespaces++;
>
> nvmet_ns_changed(subsys, ns->nsid);
> @@ -620,6 +626,8 @@ int nvmet_ns_enable(struct nvmet_ns *ns)
> mutex_unlock(&subsys->lock);
> return ret;
>
> +out_remove_from_subsys:
> + xa_erase(&subsys->namespaces, ns->nsid);
> out_restore_subsys_maxnsid:
> subsys->max_nsid = nvmet_max_nsid(subsys);
> percpu_ref_exit(&ns->ref);
> @@ -663,6 +671,9 @@ void nvmet_ns_disable(struct nvmet_ns *ns)
> wait_for_completion(&ns->disable_done);
> percpu_ref_exit(&ns->ref);
>
> + if (ns->pr.enable)
> + nvmet_pr_exit_ns(ns);
> +
> mutex_lock(&subsys->lock);
>
> subsys->nr_namespaces--;
> @@ -766,6 +777,7 @@ static void __nvmet_req_complete(struct nvmet_req *req, u16 status)
> trace_nvmet_req_complete(req);
>
> req->ops->queue_response(req);
> + nvmet_pr_put_ns_pc_ref(req);
> if (ns)
> nvmet_put_namespace(ns);
> }
> @@ -929,18 +941,39 @@ static u16 nvmet_parse_io_cmd(struct nvmet_req *req)
> return ret;
> }
>
> + if (req->ns->pr.enable) {
> + ret = nvmet_parse_pr_cmd(req);
> + if (!ret)
> + return ret;
> + }
> +
> switch (req->ns->csi) {
> case NVME_CSI_NVM:
> if (req->ns->file)
> - return nvmet_file_parse_io_cmd(req);
> - return nvmet_bdev_parse_io_cmd(req);
> + ret = nvmet_file_parse_io_cmd(req);
> + else
> + ret = nvmet_bdev_parse_io_cmd(req);
> + break;
> case NVME_CSI_ZNS:
> if (IS_ENABLED(CONFIG_BLK_DEV_ZONED))
> - return nvmet_bdev_zns_parse_io_cmd(req);
> - return NVME_SC_INVALID_IO_CMD_SET;
> + ret = nvmet_bdev_zns_parse_io_cmd(req);
> + else
> + ret = NVME_SC_INVALID_IO_CMD_SET;
> + break;
> default:
> - return NVME_SC_INVALID_IO_CMD_SET;
> + ret = NVME_SC_INVALID_IO_CMD_SET;
> + }
> + if (ret)
> + return ret;
> +
> + if (req->ns->pr.enable) {
> + ret = nvmet_pr_check_cmd_access(req);
> + if (ret)
> + return ret;
> +
> + ret = nvmet_pr_get_ns_pc_ref(req);
> }
> + return ret;
> }
>
> bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq,
> @@ -964,6 +997,7 @@ bool nvmet_req_init(struct nvmet_req *req, struct nvmet_cq *cq,
> req->ns = NULL;
> req->error_loc = NVMET_NO_ERROR_LOC;
> req->error_slba = 0;
> + req->pc_ref = NULL;
>
> /* no support for fused commands yet */
> if (unlikely(flags & (NVME_CMD_FUSE_FIRST | NVME_CMD_FUSE_SECOND))) {
> @@ -1015,6 +1049,7 @@ EXPORT_SYMBOL_GPL(nvmet_req_init);
> void nvmet_req_uninit(struct nvmet_req *req)
> {
> percpu_ref_put(&req->sq->ref);
> + nvmet_pr_put_ns_pc_ref(req);
> if (req->ns)
> nvmet_put_namespace(req->ns);
> }
> @@ -1383,7 +1418,8 @@ static void nvmet_fatal_error_handler(struct work_struct *work)
> }
>
> u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn,
> - struct nvmet_req *req, u32 kato, struct nvmet_ctrl **ctrlp)
> + struct nvmet_req *req, u32 kato, struct nvmet_ctrl **ctrlp,
> + uuid_t *hostid)
> {
> struct nvmet_subsys *subsys;
> struct nvmet_ctrl *ctrl;
> @@ -1462,6 +1498,8 @@ u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn,
> }
> ctrl->cntlid = ret;
>
> + uuid_copy(&ctrl->hostid, hostid);
> +
> /*
> * Discovery controllers may use some arbitrary high value
> * in order to cleanup stale discovery sessions
> @@ -1478,6 +1516,9 @@ u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn,
> nvmet_start_keep_alive_timer(ctrl);
>
> mutex_lock(&subsys->lock);
> + ret = nvmet_ctrl_init_pr(ctrl);
> + if (ret)
> + goto init_pr_fail;
> list_add_tail(&ctrl->subsys_entry, &subsys->ctrls);
> nvmet_setup_p2p_ns_map(ctrl, req);
> nvmet_debugfs_ctrl_setup(ctrl);
> @@ -1486,6 +1527,10 @@ u16 nvmet_alloc_ctrl(const char *subsysnqn, const char *hostnqn,
> *ctrlp = ctrl;
> return 0;
>
> +init_pr_fail:
> + mutex_unlock(&subsys->lock);
> + nvmet_stop_keep_alive_timer(ctrl);
> + ida_free(&cntlid_ida, ctrl->cntlid);
> out_free_sqs:
> kfree(ctrl->sqs);
> out_free_changed_ns_list:
> @@ -1504,6 +1549,7 @@ static void nvmet_ctrl_free(struct kref *ref)
> struct nvmet_subsys *subsys = ctrl->subsys;
>
> mutex_lock(&subsys->lock);
> + nvmet_ctrl_destroy_pr(ctrl);
> nvmet_release_p2p_ns_map(ctrl);
> list_del(&ctrl->subsys_entry);
> mutex_unlock(&subsys->lock);
> diff --git a/drivers/nvme/target/fabrics-cmd.c b/drivers/nvme/target/fabrics-cmd.c
> index c4b2eddd5666..28a84af1b4c0 100644
> --- a/drivers/nvme/target/fabrics-cmd.c
> +++ b/drivers/nvme/target/fabrics-cmd.c
> @@ -245,12 +245,10 @@ static void nvmet_execute_admin_connect(struct nvmet_req *req)
> d->subsysnqn[NVMF_NQN_FIELD_LEN - 1] = '\0';
> d->hostnqn[NVMF_NQN_FIELD_LEN - 1] = '\0';
> status = nvmet_alloc_ctrl(d->subsysnqn, d->hostnqn, req,
> - le32_to_cpu(c->kato), &ctrl);
> + le32_to_cpu(c->kato), &ctrl, &d->hostid);
> if (status)
> goto out;
>
> - uuid_copy(&ctrl->hostid, &d->hostid);
> -
> dhchap_status = nvmet_setup_auth(ctrl);
> if (dhchap_status) {
> pr_err("Failed to setup authentication, dhchap status %u\n",
> diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
> index 190f55e6d753..1e5851f6d29b 100644
> --- a/drivers/nvme/target/nvmet.h
> +++ b/drivers/nvme/target/nvmet.h
> @@ -20,6 +20,7 @@
> #include <linux/blkdev.h>
> #include <linux/radix-tree.h>
> #include <linux/t10-pi.h>
> +#include <linux/kfifo.h>
>
> #define NVMET_DEFAULT_VS NVME_VS(1, 3, 0)
>
> @@ -30,6 +31,7 @@
> #define NVMET_MN_MAX_SIZE 40
> #define NVMET_SN_MAX_SIZE 20
> #define NVMET_FR_MAX_SIZE 8
> +#define NVMET_PR_LOG_QUEUE_SIZE 64
>
> /*
> * Supported optional AENs:
> @@ -56,6 +58,38 @@
> #define IPO_IATTR_CONNECT_SQE(x) \
> (cpu_to_le32(offsetof(struct nvmf_connect_command, x)))
>
> +struct nvmet_pr_registrant {
> + u64 rkey;
> + uuid_t hostid;
> + enum nvme_pr_type rtype;
> + struct list_head entry;
> + struct rcu_head rcu;
> +};
> +
> +struct nvmet_pr {
> + bool enable;
> + unsigned long notify_mask;
> + atomic_t generation;
> + struct nvmet_pr_registrant __rcu *holder;
> + /*
> + * During the execution of the reservation command, mutual
> + * exclusion is required throughout the process. However,
> + * while waiting asynchronously for the 'per controller
> + * percpu_ref' to complete before the 'preempt and abort'
> + * command finishes, a semaphore is needed to ensure mutual
> + * exclusion instead of a mutex.
> + */
> + struct semaphore pr_sem;
> + struct list_head registrant_list;
> +};
> +
> +struct nvmet_pr_per_ctrl_ref {
> + struct percpu_ref ref;
> + struct completion free_done;
> + struct completion confirm_done;
> + uuid_t hostid;
> +};
> +
> +static void nvmet_pr_set_ctrl_to_abort(struct nvmet_req *req, uuid_t *hostid)
> +{
> + struct nvmet_pr_per_ctrl_ref *pc_ref;
> + struct nvmet_ns *ns = req->ns;
> + unsigned long idx;
> +
> + xa_for_each(&ns->pr_per_ctrl_refs, idx, pc_ref) {
> + if (uuid_equal(&pc_ref->hostid, hostid)) {
> + percpu_ref_kill_and_confirm(&pc_ref->ref,
> + nvmet_pr_confirm_ns_pc_ref);
> + wait_for_completion(&pc_ref->confirm_done);
> + }
> + }
> +}
> +
> +static void nvmet_pr_do_abort(struct work_struct *w)
> +{
> + struct nvmet_req *req = container_of(w, struct nvmet_req, r.abort_work);
> + struct nvmet_pr_per_ctrl_ref *pc_ref;
> + struct nvmet_ns *ns = req->ns;
> + unsigned long idx;
> +
> + /*
> + * The target does not support abort, just wait per-controller ref to 0.
> + */
> + xa_for_each(&ns->pr_per_ctrl_refs, idx, pc_ref) {
> + if (percpu_ref_is_dying(&pc_ref->ref)) {
> + wait_for_completion(&pc_ref->free_done);
> + reinit_completion(&pc_ref->confirm_done);
> + reinit_completion(&pc_ref->free_done);
> + percpu_ref_resurrect(&pc_ref->ref);
> + }
> + }
If you want just to protect this particular loop against of a parallel
execution, why simply not to protect it by its own mutex?
> + up(&ns->pr.pr_sem);
> + nvmet_req_complete(req, NVME_SC_SUCCESS);
> +}
> +
> +static void nvmet_execute_pr_acquire(struct nvmet_req *req)
> +{
> + u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
> + bool ignore_key = nvmet_pr_parse_ignore_key(cdw10);
> + /* Reservation type, bit 15:08 */
> + u8 rtype = (u8)((cdw10 >> 8) & 0xff);
> + /* Reservation acquire action, bit 02:00 */
> + u8 acquire_act = cdw10 & 0x07;
> + struct nvmet_ctrl *ctrl = req->sq->ctrl;
> + struct nvmet_pr_acquire_data *d = NULL;
> + struct nvmet_pr *pr = &req->ns->pr;
> + struct nvmet_pr_registrant *reg;
> + u16 status = NVME_SC_SUCCESS;
> +
> + if (ignore_key ||
> + rtype < NVME_PR_WRITE_EXCLUSIVE ||
> + rtype > NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS) {
> + status = NVME_SC_INVALID_FIELD | NVME_STATUS_DNR;
> + goto out;
> + }
> +
> + d = kmalloc(sizeof(*d), GFP_KERNEL);
> + if (!d) {
> + status = NVME_SC_INTERNAL;
> + goto out;
> + }
> +
> + status = nvmet_copy_from_sgl(req, 0, d, sizeof(*d));
> + if (status)
> + goto free_data;
> +
> + status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
> + down(&pr->pr_sem);
> + list_for_each_entry_rcu(reg, &pr->registrant_list, entry,
> + lockdep_is_held(&pr->pr_lock)) {
lockdep_is_held does not work with semaphores. Using a semaphore drops
your lockdep effort.
> + if (uuid_equal(®->hostid, &ctrl->hostid) &&
> + reg->rkey == le64_to_cpu(d->crkey)) {
> + status = __nvmet_execute_pr_acquire(req, reg,
> + acquire_act, rtype, d);
> + break;
> + }
> + }
> +
> + if (!status && acquire_act == NVME_PR_ACQUIRE_ACT_PREEMPT_AND_ABORT) {
> + kfree(d);
> + INIT_WORK(&req->r.abort_work, nvmet_pr_do_abort);
> + queue_work(nvmet_wq, &req->r.abort_work);
> + return;
> + }
> +
> + up(&pr->pr_sem);
> +
> +free_data:
> + kfree(d);
> +out:
> + nvmet_req_complete(req, status);
> +}
> +
> +u16 nvmet_pr_get_ns_pc_ref(struct nvmet_req *req)
> +{
> + struct nvmet_pr_per_ctrl_ref *pc_ref;
> +
> + pc_ref = xa_load(&req->ns->pr_per_ctrl_refs,
> + req->sq->ctrl->cntlid);
> + if (unlikely(!percpu_ref_tryget_live(&pc_ref->ref)))
> + return NVME_SC_INTERNAL;
> + req->pc_ref = pc_ref;
> + return NVME_SC_SUCCESS;
> +}
> +
> +static void nvmet_pr_ctrl_ns_all_cmds_done(struct percpu_ref *ref)
> +{
> + struct nvmet_pr_per_ctrl_ref *pc_ref =
> + container_of(ref, struct nvmet_pr_per_ctrl_ref, ref);
> +
> + complete(&pc_ref->free_done);
> +}
> +
> +static int nvmet_pr_alloc_and_insert_pc_ref(struct nvmet_ns *ns,
> + unsigned long idx,
> + uuid_t *hostid)
> +{
> + struct nvmet_pr_per_ctrl_ref *pc_ref;
> + int ret;
> +
> + pc_ref = kmalloc(sizeof(*pc_ref), GFP_ATOMIC);
> + if (!pc_ref)
> + return -ENOMEM;
> +
> + ret = percpu_ref_init(&pc_ref->ref, nvmet_pr_ctrl_ns_all_cmds_done,
> + PERCPU_REF_ALLOW_REINIT, GFP_KERNEL);
> + if (ret)
> + goto free;
> +
> + init_completion(&pc_ref->free_done);
> + init_completion(&pc_ref->confirm_done);
> + uuid_copy(&pc_ref->hostid, hostid);
> +
> + ret = xa_insert(&ns->pr_per_ctrl_refs, idx, pc_ref, GFP_KERNEL);
> + if (ret)
> + goto exit;
> + return ret;
> +exit:
> + percpu_ref_exit(&pc_ref->ref);
> +free:
> + kfree(pc_ref);
> + return ret;
> +}
> +
> +int nvmet_ctrl_init_pr(struct nvmet_ctrl *ctrl)
> +{
> + struct nvmet_subsys *subsys = ctrl->subsys;
> + struct nvmet_pr_per_ctrl_ref *pc_ref;
> + struct nvmet_ns *ns = NULL;
> + unsigned long idx;
> + int ret;
> +
> + ctrl->pr_log_mgr.counter = 0;
> + ctrl->pr_log_mgr.lost_count = 0;
> + mutex_init(&ctrl->pr_log_mgr.lock);
> + INIT_KFIFO(ctrl->pr_log_mgr.log_queue);
> +
> + /*
> + * Here we are under subsys lock, if an ns not in subsys->namespaces,
> + * we can make sure that ns is not enabled, and not call
> + * nvmet_pr_init_ns(), see more details in nvmet_ns_enable().
> + * So just check ns->pr.enable.
> + */
> + xa_for_each(&subsys->namespaces, idx, ns) {
> + if (ns->pr.enable) {
> + ret = nvmet_pr_alloc_and_insert_pc_ref(ns, ctrl->cntlid,
> + &ctrl->hostid);
> + if (ret)
> + goto free_per_ctrl_refs;
> + }
> + }
> + return 0;
> +
> +free_per_ctrl_refs:
> + xa_for_each(&subsys->namespaces, idx, ns) {
> + if (ns->pr.enable) {
> + pc_ref = xa_erase(&ns->pr_per_ctrl_refs, ctrl->cntlid);
> + if (pc_ref)
> + percpu_ref_exit(&pc_ref->ref);
> + kfree(pc_ref);
> + }
> + }
> + return ret;
> +}
> +
> +void nvmet_ctrl_destroy_pr(struct nvmet_ctrl *ctrl)
> +{
> + struct nvmet_pr_per_ctrl_ref *pc_ref;
> + struct nvmet_ns *ns;
> + unsigned long idx;
> +
> + kfifo_free(&ctrl->pr_log_mgr.log_queue);
> + mutex_destroy(&ctrl->pr_log_mgr.lock);
> +
> + xa_for_each(&ctrl->subsys->namespaces, idx, ns) {
> + if (ns->pr.enable) {
> + pc_ref = xa_erase(&ns->pr_per_ctrl_refs, ctrl->cntlid);
> + if (pc_ref)
> + percpu_ref_exit(&pc_ref->ref);
> + kfree(pc_ref);
> + }
> + }
> +}
> +
> +int nvmet_pr_init_ns(struct nvmet_ns *ns)
> +{
> + struct nvmet_subsys *subsys = ns->subsys;
> + struct nvmet_pr_per_ctrl_ref *pc_ref;
> + struct nvmet_ctrl *ctrl = NULL;
> + unsigned long idx;
> + int ret;
> +
> + ns->pr.holder = NULL;
> + atomic_set(&ns->pr.generation, 0);
> + sema_init(&ns->pr.pr_sem, 1);
> + INIT_LIST_HEAD(&ns->pr.registrant_list);
> + ns->pr.notify_mask = 0;
> +
> + xa_init(&ns->pr_per_ctrl_refs);
> +
> + list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
> + ret = nvmet_pr_alloc_and_insert_pc_ref(ns, ctrl->cntlid,
> + &ctrl->hostid);
> + if (ret)
> + goto free_per_ctrl_refs;
> + }
> + return 0;
> +
> +free_per_ctrl_refs:
> + xa_for_each(&ns->pr_per_ctrl_refs, idx, pc_ref) {
> + xa_erase(&ns->pr_per_ctrl_refs, idx);
> + percpu_ref_exit(&pc_ref->ref);
> + kfree(pc_ref);
> + }
> + return ret;
> +}
> +
> +void nvmet_pr_exit_ns(struct nvmet_ns *ns)
> +{
> + struct nvmet_pr_registrant *reg, *tmp;
> + struct nvmet_pr_per_ctrl_ref *pc_ref;
> + struct nvmet_pr *pr = &ns->pr;
> + unsigned long idx;
> +
> + list_for_each_entry_safe(reg, tmp, &pr->registrant_list, entry) {
> + list_del(®->entry);
> + kfree(reg);
> + }
> +
> + xa_for_each(&ns->pr_per_ctrl_refs, idx, pc_ref) {
> + /*
> + * No command on ns here, we can safely free pc_ref.
> + */
> + pc_ref = xa_erase(&ns->pr_per_ctrl_refs, idx);
> + percpu_ref_exit(&pc_ref->ref);
> + kfree(pc_ref);
> + }
> +
> + xa_destroy(&ns->pr_per_ctrl_refs);
> +}
> --
> 2.43.0
BR,
Dmitry
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