--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * NVMe over Fabrics Persist Reservation.
+ * Copyright (c) 2024 Guixin Liu, Alibaba Group.
+ * All rights reserved.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/unaligned.h>
+#include "nvmet.h"
+
+#define NVMET_PR_NOTIFI_MASK_ALL \
+ (1 << NVME_PR_NOTIFY_BIT_REG_PREEMPTED | \
+ 1 << NVME_PR_NOTIFY_BIT_RESV_RELEASED | \
+ 1 << NVME_PR_NOTIFY_BIT_RESV_PREEMPTED)
+
+static inline bool nvmet_pr_parse_ignore_key(u32 cdw10)
+{
+ /* Ignore existing key, bit 03. */
+ return (cdw10 >> 3) & 1;
+}
+
+static inline struct nvmet_ns *nvmet_pr_to_ns(struct nvmet_pr *pr)
+{
+ return container_of(pr, struct nvmet_ns, pr);
+}
+
+static struct nvmet_pr_registrant *
+nvmet_pr_find_registrant(struct nvmet_pr *pr, uuid_t *hostid)
+{
+ struct nvmet_pr_registrant *reg;
+
+ list_for_each_entry_rcu(reg, &pr->registrant_list, entry) {
+ if (uuid_equal(®->hostid, hostid))
+ return reg;
+ }
+ return NULL;
+}
+
+u16 nvmet_set_feat_resv_notif_mask(struct nvmet_req *req, u32 mask)
+{
+ u32 nsid = le32_to_cpu(req->cmd->common.nsid);
+ struct nvmet_ctrl *ctrl = req->sq->ctrl;
+ struct nvmet_ns *ns;
+ unsigned long idx;
+ u16 status;
+
+ if (mask & ~(NVMET_PR_NOTIFI_MASK_ALL)) {
+ req->error_loc = offsetof(struct nvme_common_command, cdw11);
+ return NVME_SC_INVALID_FIELD | NVME_STATUS_DNR;
+ }
+
+ if (nsid != U32_MAX) {
+ status = nvmet_req_find_ns(req);
+ if (status)
+ return status;
+ if (!req->ns->pr.enable)
+ return NVME_SC_INVALID_FIELD | NVME_STATUS_DNR;
+
+ WRITE_ONCE(req->ns->pr.notify_mask, mask);
+ goto success;
+ }
+
+ xa_for_each(&ctrl->subsys->namespaces, idx, ns) {
+ if (ns->pr.enable)
+ WRITE_ONCE(ns->pr.notify_mask, mask);
+ }
+
+success:
+ nvmet_set_result(req, mask);
+ return NVME_SC_SUCCESS;
+}
+
+u16 nvmet_get_feat_resv_notif_mask(struct nvmet_req *req)
+{
+ u16 status;
+
+ status = nvmet_req_find_ns(req);
+ if (status)
+ return status;
+
+ if (!req->ns->pr.enable)
+ return NVME_SC_INVALID_FIELD | NVME_STATUS_DNR;
+
+ nvmet_set_result(req, READ_ONCE(req->ns->pr.notify_mask));
+ return status;
+}
+
+void nvmet_execute_get_log_page_resv(struct nvmet_req *req)
+{
+ struct nvmet_pr_log_mgr *log_mgr = &req->sq->ctrl->pr_log_mgr;
+ struct nvme_pr_log next_log = {0};
+ struct nvme_pr_log log = {0};
+ u16 status = NVME_SC_SUCCESS;
+ u64 lost_count;
+ u64 cur_count;
+ u64 next_count;
+
+ mutex_lock(&log_mgr->lock);
+ if (!kfifo_get(&log_mgr->log_queue, &log))
+ goto out;
+
+ /*
+ * We can't get the last in kfifo.
+ * Utilize the current count and the count from the next log to
+ * calculate the number of lost logs, while also addressing cases
+ * of overflow. If there is no subsequent log, the number of lost
+ * logs is equal to the lost_count within the nvmet_pr_log_mgr.
+ */
+ cur_count = le64_to_cpu(log.count);
+ if (kfifo_peek(&log_mgr->log_queue, &next_log)) {
+ next_count = le64_to_cpu(next_log.count);
+ if (next_count > cur_count)
+ lost_count = next_count - cur_count - 1;
+ else
+ lost_count = U64_MAX - cur_count + next_count - 1;
+ } else {
+ lost_count = log_mgr->lost_count;
+ }
+
+ log.count = cpu_to_le64((cur_count + lost_count) == 0 ?
+ 1 : (cur_count + lost_count));
+ log_mgr->lost_count -= lost_count;
+
+ log.nr_pages = kfifo_len(&log_mgr->log_queue);
+
+out:
+ status = nvmet_copy_to_sgl(req, 0, &log, sizeof(log));
+ mutex_unlock(&log_mgr->lock);
+ nvmet_req_complete(req, status);
+}
+
+static void nvmet_pr_add_resv_log(struct nvmet_ctrl *ctrl, u8 log_type,
+ u32 nsid)
+{
+ struct nvmet_pr_log_mgr *log_mgr = &ctrl->pr_log_mgr;
+ struct nvme_pr_log log = {0};
+
+ mutex_lock(&log_mgr->lock);
+ log_mgr->counter++;
+ if (log_mgr->counter == 0)
+ log_mgr->counter = 1;
+
+ log.count = cpu_to_le64(log_mgr->counter);
+ log.type = log_type;
+ log.nsid = cpu_to_le32(nsid);
+
+ if (!kfifo_put(&log_mgr->log_queue, log)) {
+ pr_info("a reservation log lost, cntlid:%d, log_type:%d, nsid:%d\n",
+ ctrl->cntlid, log_type, nsid);
+ log_mgr->lost_count++;
+ }
+
+ mutex_unlock(&log_mgr->lock);
+}
+
+static void nvmet_pr_resv_released(struct nvmet_pr *pr, uuid_t *hostid)
+{
+ struct nvmet_ns *ns = nvmet_pr_to_ns(pr);
+ struct nvmet_subsys *subsys = ns->subsys;
+ struct nvmet_ctrl *ctrl;
+
+ if (test_bit(NVME_PR_NOTIFY_BIT_RESV_RELEASED, &pr->notify_mask))
+ return;
+
+ mutex_lock(&subsys->lock);
+ list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
+ if (!uuid_equal(&ctrl->hostid, hostid) &&
+ nvmet_pr_find_registrant(pr, &ctrl->hostid)) {
+ nvmet_pr_add_resv_log(ctrl,
+ NVME_PR_LOG_RESERVATION_RELEASED, ns->nsid);
+ nvmet_add_async_event(ctrl, NVME_AER_CSS,
+ NVME_AEN_RESV_LOG_PAGE_AVALIABLE,
+ NVME_LOG_RESERVATION);
+ }
+ }
+ mutex_unlock(&subsys->lock);
+}
+
+static void nvmet_pr_send_event_to_host(struct nvmet_pr *pr, uuid_t *hostid,
+ u8 log_type)
+{
+ struct nvmet_ns *ns = nvmet_pr_to_ns(pr);
+ struct nvmet_subsys *subsys = ns->subsys;
+ struct nvmet_ctrl *ctrl;
+
+ mutex_lock(&subsys->lock);
+ list_for_each_entry(ctrl, &subsys->ctrls, subsys_entry) {
+ if (uuid_equal(hostid, &ctrl->hostid)) {
+ nvmet_pr_add_resv_log(ctrl, log_type, ns->nsid);
+ nvmet_add_async_event(ctrl, NVME_AER_CSS,
+ NVME_AEN_RESV_LOG_PAGE_AVALIABLE,
+ NVME_LOG_RESERVATION);
+ }
+ }
+ mutex_unlock(&subsys->lock);
+}
+
+static void nvmet_pr_resv_preempted(struct nvmet_pr *pr, uuid_t *hostid)
+{
+ if (test_bit(NVME_PR_NOTIFY_BIT_RESV_PREEMPTED, &pr->notify_mask))
+ return;
+
+ nvmet_pr_send_event_to_host(pr, hostid,
+ NVME_PR_LOG_RESERVATOIN_PREEMPTED);
+}
+
+static void nvmet_pr_registration_preempted(struct nvmet_pr *pr,
+ uuid_t *hostid)
+{
+ if (test_bit(NVME_PR_NOTIFY_BIT_REG_PREEMPTED, &pr->notify_mask))
+ return;
+
+ nvmet_pr_send_event_to_host(pr, hostid,
+ NVME_PR_LOG_REGISTRATION_PREEMPTED);
+}
+
+static inline void nvmet_pr_set_new_holder(struct nvmet_pr *pr, u8 new_rtype,
+ struct nvmet_pr_registrant *reg)
+{
+ reg->rtype = new_rtype;
+ rcu_assign_pointer(pr->holder, reg);
+}
+
+static u16 nvmet_pr_register(struct nvmet_req *req,
+ struct nvmet_pr_register_data *d)
+{
+ struct nvmet_ctrl *ctrl = req->sq->ctrl;
+ struct nvmet_pr_registrant *new, *reg;
+ struct nvmet_pr *pr = &req->ns->pr;
+ u16 status = NVME_SC_SUCCESS;
+ u64 nrkey = le64_to_cpu(d->nrkey);
+
+ new = kmalloc(sizeof(*new), GFP_KERNEL);
+ if (!new)
+ return NVME_SC_INTERNAL;
+
+ down(&pr->pr_sem);
+ reg = nvmet_pr_find_registrant(pr, &ctrl->hostid);
+ if (reg) {
+ if (reg->rkey != nrkey)
+ status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
+ kfree(new);
+ goto out;
+ }
+
+ memset(new, 0, sizeof(*new));
+ INIT_LIST_HEAD(&new->entry);
+ new->rkey = nrkey;
+ uuid_copy(&new->hostid, &ctrl->hostid);
+ list_add_tail_rcu(&new->entry, &pr->registrant_list);
+
+out:
+ up(&pr->pr_sem);
+ return status;
+}
+
+static void nvmet_pr_unregister_one(struct nvmet_pr *pr,
+ struct nvmet_pr_registrant *reg)
+{
+ struct nvmet_pr_registrant *first_reg;
+ struct nvmet_pr_registrant *holder;
+ u8 original_rtype;
+
+ list_del_rcu(®->entry);
+
+ holder = rcu_dereference_protected(pr->holder, 1);
+ if (reg != holder)
+ goto out;
+
+ original_rtype = holder->rtype;
+ if (original_rtype == NVME_PR_WRITE_EXCLUSIVE_ALL_REGS ||
+ original_rtype == NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS) {
+ first_reg = list_first_or_null_rcu(&pr->registrant_list,
+ struct nvmet_pr_registrant, entry);
+ if (first_reg)
+ first_reg->rtype = original_rtype;
+ rcu_assign_pointer(pr->holder, first_reg);
+ } else {
+ rcu_assign_pointer(pr->holder, NULL);
+
+ if (original_rtype == NVME_PR_WRITE_EXCLUSIVE_REG_ONLY ||
+ original_rtype == NVME_PR_EXCLUSIVE_ACCESS_REG_ONLY)
+ nvmet_pr_resv_released(pr, ®->hostid);
+ }
+out:
+ kfree_rcu(reg, rcu);
+}
+
+static u16 nvmet_pr_unregister(struct nvmet_req *req,
+ struct nvmet_pr_register_data *d,
+ bool ignore_key)
+{
+ u16 status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
+ struct nvmet_ctrl *ctrl = req->sq->ctrl;
+ struct nvmet_pr *pr = &req->ns->pr;
+ struct nvmet_pr_registrant *reg;
+
+ down(&pr->pr_sem);
+ list_for_each_entry_rcu(reg, &pr->registrant_list, entry) {
+ if (uuid_equal(®->hostid, &ctrl->hostid)) {
+ if (ignore_key || reg->rkey == le64_to_cpu(d->crkey)) {
+ status = NVME_SC_SUCCESS;
+ nvmet_pr_unregister_one(pr, reg);
+ }
+ break;
+ }
+ }
+ up(&pr->pr_sem);
+
+ return status;
+}
+
+static void nvmet_pr_update_reg_rkey(struct nvmet_pr_registrant *reg,
+ void *attr)
+{
+ reg->rkey = *(u64 *)attr;
+}
+
+static u16 nvmet_pr_update_reg_attr(struct nvmet_pr *pr,
+ struct nvmet_pr_registrant *reg,
+ void (*change_attr)(struct nvmet_pr_registrant *reg,
+ void *attr),
+ void *attr)
+{
+ struct nvmet_pr_registrant *holder;
+ struct nvmet_pr_registrant *new;
+
+ holder = rcu_dereference_protected(pr->holder, 1);
+ if (reg != holder) {
+ change_attr(reg, attr);
+ return NVME_SC_SUCCESS;
+ }
+
+ new = kmalloc(sizeof(*new), GFP_ATOMIC);
+ if (!new)
+ return NVME_SC_INTERNAL;
+
+ new->rkey = holder->rkey;
+ new->rtype = holder->rtype;
+ uuid_copy(&new->hostid, &holder->hostid);
+ INIT_LIST_HEAD(&new->entry);
+
+ change_attr(new, attr);
+ list_replace_rcu(&holder->entry, &new->entry);
+ rcu_assign_pointer(pr->holder, new);
+ kfree_rcu(holder, rcu);
+
+ return NVME_SC_SUCCESS;
+}
+
+static u16 nvmet_pr_replace(struct nvmet_req *req,
+ struct nvmet_pr_register_data *d,
+ bool ignore_key)
+{
+ u16 status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
+ struct nvmet_ctrl *ctrl = req->sq->ctrl;
+ struct nvmet_pr *pr = &req->ns->pr;
+ struct nvmet_pr_registrant *reg;
+ u64 nrkey = le64_to_cpu(d->nrkey);
+
+ down(&pr->pr_sem);
+ list_for_each_entry_rcu(reg, &pr->registrant_list, entry) {
+ if (uuid_equal(®->hostid, &ctrl->hostid)) {
+ if (ignore_key || reg->rkey == le64_to_cpu(d->crkey))
+ status = nvmet_pr_update_reg_attr(pr, reg,
+ nvmet_pr_update_reg_rkey,
+ &nrkey);
+ break;
+ }
+ }
+ up(&pr->pr_sem);
+ return status;
+}
+
+static void nvmet_execute_pr_register(struct nvmet_req *req)
+{
+ u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
+ bool ignore_key = nvmet_pr_parse_ignore_key(cdw10);
+ struct nvmet_pr_register_data *d;
+ u8 reg_act = cdw10 & 0x07; /* Reservation Register Action, bit 02:00 */
+ u16 status;
+
+ 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;
+
+ switch (reg_act) {
+ case NVME_PR_REGISTER_ACT_REG:
+ status = nvmet_pr_register(req, d);
+ break;
+ case NVME_PR_REGISTER_ACT_UNREG:
+ status = nvmet_pr_unregister(req, d, ignore_key);
+ break;
+ case NVME_PR_REGISTER_ACT_REPLACE:
+ status = nvmet_pr_replace(req, d, ignore_key);
+ break;
+ default:
+ req->error_loc = offsetof(struct nvme_common_command, cdw10);
+ status = NVME_SC_INVALID_OPCODE | NVME_STATUS_DNR;
+ break;
+ }
+free_data:
+ kfree(d);
+out:
+ if (!status)
+ atomic_inc(&req->ns->pr.generation);
+ nvmet_req_complete(req, status);
+}
+
+static u16 nvmet_pr_acquire(struct nvmet_req *req,
+ struct nvmet_pr_registrant *reg,
+ u8 rtype)
+{
+ struct nvmet_pr *pr = &req->ns->pr;
+ struct nvmet_pr_registrant *holder;
+
+ holder = rcu_dereference_protected(pr->holder, 1);
+ if (holder && reg != holder)
+ return NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
+ if (holder && reg == holder) {
+ if (holder->rtype == rtype)
+ return NVME_SC_SUCCESS;
+ return NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
+ }
+
+ nvmet_pr_set_new_holder(pr, rtype, reg);
+ return NVME_SC_SUCCESS;
+}
+
+static void nvmet_pr_confirm_ns_pc_ref(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->confirm_done);
+}
+
+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 u16 nvmet_pr_unreg_all_host_by_prkey(struct nvmet_req *req, u64 prkey,
+ uuid_t *send_hostid,
+ bool abort)
+{
+ u16 status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
+ struct nvmet_pr_registrant *reg, *tmp;
+ struct nvmet_pr *pr = &req->ns->pr;
+ uuid_t hostid;
+
+ list_for_each_entry_safe(reg, tmp, &pr->registrant_list, entry) {
+ if (reg->rkey == prkey) {
+ status = NVME_SC_SUCCESS;
+ uuid_copy(&hostid, ®->hostid);
+ if (abort)
+ nvmet_pr_set_ctrl_to_abort(req, &hostid);
+ nvmet_pr_unregister_one(pr, reg);
+ if (!uuid_equal(&hostid, send_hostid))
+ nvmet_pr_registration_preempted(pr, &hostid);
+ }
+ }
+ return status;
+}
+
+static void nvmet_pr_unreg_all_others_by_prkey(struct nvmet_req *req,
+ u64 prkey,
+ uuid_t *send_hostid,
+ bool abort)
+{
+ struct nvmet_pr_registrant *reg, *tmp;
+ struct nvmet_pr *pr = &req->ns->pr;
+ uuid_t hostid;
+
+ list_for_each_entry_safe(reg, tmp, &pr->registrant_list, entry) {
+ if (reg->rkey == prkey &&
+ !uuid_equal(®->hostid, send_hostid)) {
+ uuid_copy(&hostid, ®->hostid);
+ if (abort)
+ nvmet_pr_set_ctrl_to_abort(req, &hostid);
+ nvmet_pr_unregister_one(pr, reg);
+ nvmet_pr_registration_preempted(pr, &hostid);
+ }
+ }
+}
+
+static void nvmet_pr_unreg_all_others(struct nvmet_req *req,
+ uuid_t *send_hostid,
+ bool abort)
+{
+ struct nvmet_pr_registrant *reg, *tmp;
+ struct nvmet_pr *pr = &req->ns->pr;
+ uuid_t hostid;
+
+ list_for_each_entry_safe(reg, tmp, &pr->registrant_list, entry) {
+ if (!uuid_equal(®->hostid, send_hostid)) {
+ uuid_copy(&hostid, ®->hostid);
+ if (abort)
+ nvmet_pr_set_ctrl_to_abort(req, &hostid);
+ nvmet_pr_unregister_one(pr, reg);
+ nvmet_pr_registration_preempted(pr, &hostid);
+ }
+ }
+}
+
+static void nvmet_pr_update_holder_rtype(struct nvmet_pr_registrant *reg,
+ void *attr)
+{
+ u8 new_rtype = *(u8 *)attr;
+
+ reg->rtype = new_rtype;
+}
+
+static u16 nvmet_pr_preempt(struct nvmet_req *req,
+ struct nvmet_pr_registrant *reg,
+ u8 rtype,
+ struct nvmet_pr_acquire_data *d,
+ bool abort)
+{
+ struct nvmet_ctrl *ctrl = req->sq->ctrl;
+ struct nvmet_pr *pr = &req->ns->pr;
+ struct nvmet_pr_registrant *holder;
+ enum nvme_pr_type original_rtype;
+ u64 prkey = le64_to_cpu(d->prkey);
+ u16 status;
+
+ holder = rcu_dereference_protected(pr->holder, 1);
+ if (!holder)
+ return nvmet_pr_unreg_all_host_by_prkey(req, prkey,
+ &ctrl->hostid, abort);
+
+ original_rtype = holder->rtype;
+ if (original_rtype == NVME_PR_WRITE_EXCLUSIVE_ALL_REGS ||
+ original_rtype == NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS) {
+ if (!prkey) {
+ /*
+ * To prevent possible access from other hosts, and
+ * avoid terminate the holder, set the new holder
+ * first before unregistering.
+ */
+ nvmet_pr_set_new_holder(pr, rtype, reg);
+ nvmet_pr_unreg_all_others(req, &ctrl->hostid, abort);
+ return NVME_SC_SUCCESS;
+ }
+ return nvmet_pr_unreg_all_host_by_prkey(req, prkey,
+ &ctrl->hostid, abort);
+ }
+
+ if (holder == reg) {
+ status = nvmet_pr_update_reg_attr(pr, holder,
+ nvmet_pr_update_holder_rtype, &rtype);
+ if (!status && original_rtype != rtype)
+ nvmet_pr_resv_released(pr, ®->hostid);
+ return status;
+ }
+
+ if (prkey == holder->rkey) {
+ /*
+ * Same as before, set the new holder first.
+ */
+ nvmet_pr_set_new_holder(pr, rtype, reg);
+ nvmet_pr_unreg_all_others_by_prkey(req, prkey, &ctrl->hostid,
+ abort);
+ if (original_rtype != rtype)
+ nvmet_pr_resv_released(pr, ®->hostid);
+ return NVME_SC_SUCCESS;
+ }
+
+ if (prkey)
+ return nvmet_pr_unreg_all_host_by_prkey(req, prkey,
+ &ctrl->hostid, abort);
+ return NVME_SC_INVALID_FIELD | NVME_STATUS_DNR;
+}
+
+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);
+ }
+ }
+
+ up(&ns->pr.pr_sem);
+ nvmet_req_complete(req, NVME_SC_SUCCESS);
+}
+
+static u16 __nvmet_execute_pr_acquire(struct nvmet_req *req,
+ struct nvmet_pr_registrant *reg,
+ u8 acquire_act,
+ u8 rtype,
+ struct nvmet_pr_acquire_data *d)
+{
+ u16 status;
+
+ switch (acquire_act) {
+ case NVME_PR_ACQUIRE_ACT_ACQUIRE:
+ status = nvmet_pr_acquire(req, reg, rtype);
+ goto out;
+ case NVME_PR_ACQUIRE_ACT_PREEMPT:
+ status = nvmet_pr_preempt(req, reg, rtype, d, false);
+ goto inc_gen;
+ case NVME_PR_ACQUIRE_ACT_PREEMPT_AND_ABORT:
+ status = nvmet_pr_preempt(req, reg, rtype, d, true);
+ goto inc_gen;
+ default:
+ req->error_loc = offsetof(struct nvme_common_command, cdw10);
+ status = NVME_SC_INVALID_OPCODE | NVME_STATUS_DNR;
+ goto out;
+ }
+inc_gen:
+ if (!status)
+ atomic_inc(&req->ns->pr.generation);
+out:
+ return status;
+}
+
+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) {
+ 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);
+}
+
+static u16 nvmet_pr_release(struct nvmet_req *req,
+ struct nvmet_pr_registrant *reg,
+ u8 rtype)
+{
+ struct nvmet_pr *pr = &req->ns->pr;
+ struct nvmet_pr_registrant *holder;
+ u8 original_rtype;
+
+ holder = rcu_dereference_protected(pr->holder, 1);
+ if (!holder || reg != holder)
+ return NVME_SC_SUCCESS;
+
+ original_rtype = holder->rtype;
+ if (original_rtype != rtype)
+ return NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
+
+ rcu_assign_pointer(pr->holder, NULL);
+
+ if (original_rtype != NVME_PR_WRITE_EXCLUSIVE &&
+ original_rtype != NVME_PR_EXCLUSIVE_ACCESS)
+ nvmet_pr_resv_released(pr, ®->hostid);
+
+ return NVME_SC_SUCCESS;
+}
+
+static void nvmet_pr_clear(struct nvmet_req *req)
+{
+ struct nvmet_pr_registrant *reg, *tmp;
+ struct nvmet_pr *pr = &req->ns->pr;
+
+ rcu_assign_pointer(pr->holder, NULL);
+
+ list_for_each_entry_safe(reg, tmp, &pr->registrant_list, entry) {
+ list_del_rcu(®->entry);
+ if (!uuid_equal(&req->sq->ctrl->hostid, ®->hostid))
+ nvmet_pr_resv_preempted(pr, ®->hostid);
+ kfree_rcu(reg, rcu);
+ }
+
+ atomic_inc(&pr->generation);
+}
+
+static u16 __nvmet_execute_pr_release(struct nvmet_req *req,
+ struct nvmet_pr_registrant *reg,
+ u8 release_act, u8 rtype)
+{
+ switch (release_act) {
+ case NVME_PR_RELEASE_ACT_RELEASE:
+ return nvmet_pr_release(req, reg, rtype);
+ case NVME_PR_RELEASE_ACT_CLEAR:
+ nvmet_pr_clear(req);
+ return NVME_SC_SUCCESS;
+ default:
+ req->error_loc = offsetof(struct nvme_common_command, cdw10);
+ return NVME_SC_INVALID_OPCODE | NVME_STATUS_DNR;
+ }
+}
+
+static void nvmet_execute_pr_release(struct nvmet_req *req)
+{
+ u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
+ bool ignore_key = nvmet_pr_parse_ignore_key(cdw10);
+ u8 rtype = (u8)((cdw10 >> 8) & 0xff); /* Reservation type, bit 15:08 */
+ u8 release_act = cdw10 & 0x07; /* Reservation release action, bit 02:00 */
+ struct nvmet_ctrl *ctrl = req->sq->ctrl;
+ struct nvmet_pr *pr = &req->ns->pr;
+ struct nvmet_pr_release_data *d;
+ struct nvmet_pr_registrant *reg;
+ u16 status;
+
+ if (ignore_key) {
+ 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) {
+ if (uuid_equal(®->hostid, &ctrl->hostid) &&
+ reg->rkey == le64_to_cpu(d->crkey)) {
+ status = __nvmet_execute_pr_release(req, reg,
+ release_act, rtype);
+ break;
+ }
+ }
+ up(&pr->pr_sem);
+free_data:
+ kfree(d);
+out:
+ nvmet_req_complete(req, status);
+}
+
+static void nvmet_execute_pr_report(struct nvmet_req *req)
+{
+ u32 cdw11 = le32_to_cpu(req->cmd->common.cdw11);
+ u32 cdw10 = le32_to_cpu(req->cmd->common.cdw10);
+ u32 num_bytes = 4 * (cdw10 + 1); /* cdw10 is number of dwords */
+ u8 eds = cdw11 & 1; /* Extended data structure, bit 00 */
+ struct nvme_registered_ctrl_ext *ctrl_eds;
+ struct nvme_reservation_status_ext *data;
+ struct nvmet_pr *pr = &req->ns->pr;
+ struct nvmet_pr_registrant *holder;
+ struct nvmet_pr_registrant *reg;
+ u16 num_ctrls = 0;
+ u16 status;
+ u8 rtype;
+
+ /* nvmet hostid(uuid_t) is 128 bit. */
+ if (!eds) {
+ req->error_loc = offsetof(struct nvme_common_command, cdw11);
+ status = NVME_SC_HOST_ID_INCONSIST | NVME_STATUS_DNR;
+ goto out;
+ }
+
+ if (num_bytes < sizeof(struct nvme_reservation_status_ext)) {
+ req->error_loc = offsetof(struct nvme_common_command, cdw10);
+ status = NVME_SC_INVALID_FIELD | NVME_STATUS_DNR;
+ goto out;
+ }
+
+ data = kmalloc(num_bytes, GFP_KERNEL);
+ if (!data) {
+ status = NVME_SC_INTERNAL;
+ goto out;
+ }
+ memset(data, 0, num_bytes);
+ data->gen = cpu_to_le32(atomic_read(&pr->generation));
+ data->ptpls = 0;
+ ctrl_eds = data->regctl_eds;
+
+ rcu_read_lock();
+ holder = rcu_dereference(pr->holder);
+ rtype = holder ? holder->rtype : 0;
+ data->rtype = rtype;
+
+ list_for_each_entry_rcu(reg, &pr->registrant_list, entry) {
+ num_ctrls++;
+ /*
+ * continue to get the number of all registrans.
+ */
+ if (((void *)ctrl_eds + sizeof(*ctrl_eds)) >
+ ((void *)data + num_bytes))
+ continue;
+ /*
+ * Dynamic controller, set cntlid to 0xffff.
+ */
+ ctrl_eds->cntlid = cpu_to_le16(NVME_CNTLID_DYNAMIC);
+ if (rtype == NVME_PR_WRITE_EXCLUSIVE_ALL_REGS ||
+ rtype == NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS)
+ ctrl_eds->rcsts = 1;
+ if (reg == holder)
+ ctrl_eds->rcsts = 1;
+ uuid_copy((uuid_t *)&ctrl_eds->hostid, ®->hostid);
+ ctrl_eds->rkey = cpu_to_le64(reg->rkey);
+ ctrl_eds++;
+ }
+ rcu_read_unlock();
+
+ put_unaligned_le16(num_ctrls, data->regctl);
+ status = nvmet_copy_to_sgl(req, 0, data, num_bytes);
+ kfree(data);
+out:
+ nvmet_req_complete(req, status);
+}
+
+u16 nvmet_parse_pr_cmd(struct nvmet_req *req)
+{
+ struct nvme_command *cmd = req->cmd;
+
+ switch (cmd->common.opcode) {
+ case nvme_cmd_resv_register:
+ req->execute = nvmet_execute_pr_register;
+ break;
+ case nvme_cmd_resv_acquire:
+ req->execute = nvmet_execute_pr_acquire;
+ break;
+ case nvme_cmd_resv_release:
+ req->execute = nvmet_execute_pr_release;
+ break;
+ case nvme_cmd_resv_report:
+ req->execute = nvmet_execute_pr_report;
+ break;
+ default:
+ return 1;
+ }
+ return NVME_SC_SUCCESS;
+}
+
+static bool nvmet_is_req_write_cmd_group(struct nvmet_req *req)
+{
+ u8 opcode = req->cmd->common.opcode;
+
+ if (req->sq->qid) {
+ switch (opcode) {
+ case nvme_cmd_flush:
+ case nvme_cmd_write:
+ case nvme_cmd_write_zeroes:
+ case nvme_cmd_dsm:
+ case nvme_cmd_zone_append:
+ case nvme_cmd_zone_mgmt_send:
+ return true;
+ default:
+ return false;
+ }
+ }
+ return false;
+}
+
+static bool nvmet_is_req_read_cmd_group(struct nvmet_req *req)
+{
+ u8 opcode = req->cmd->common.opcode;
+
+ if (req->sq->qid) {
+ switch (opcode) {
+ case nvme_cmd_read:
+ case nvme_cmd_zone_mgmt_recv:
+ return true;
+ default:
+ return false;
+ }
+ }
+ return false;
+}
+
+u16 nvmet_pr_check_cmd_access(struct nvmet_req *req)
+{
+ struct nvmet_ctrl *ctrl = req->sq->ctrl;
+ struct nvmet_pr_registrant *holder;
+ struct nvmet_ns *ns = req->ns;
+ struct nvmet_pr *pr = &ns->pr;
+ u16 status = NVME_SC_SUCCESS;
+
+ rcu_read_lock();
+ holder = rcu_dereference(pr->holder);
+ if (!holder)
+ goto unlock;
+ if (uuid_equal(&ctrl->hostid, &holder->hostid))
+ goto unlock;
+
+ /*
+ * The Reservation command group is checked in executing,
+ * allow it here.
+ */
+ switch (holder->rtype) {
+ case NVME_PR_WRITE_EXCLUSIVE:
+ if (nvmet_is_req_write_cmd_group(req))
+ status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
+ break;
+ case NVME_PR_EXCLUSIVE_ACCESS:
+ if (nvmet_is_req_read_cmd_group(req) ||
+ nvmet_is_req_write_cmd_group(req))
+ status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
+ break;
+ case NVME_PR_WRITE_EXCLUSIVE_REG_ONLY:
+ case NVME_PR_WRITE_EXCLUSIVE_ALL_REGS:
+ if ((nvmet_is_req_write_cmd_group(req)) &&
+ !nvmet_pr_find_registrant(pr, &ctrl->hostid))
+ status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
+ break;
+ case NVME_PR_EXCLUSIVE_ACCESS_REG_ONLY:
+ case NVME_PR_EXCLUSIVE_ACCESS_ALL_REGS:
+ if ((nvmet_is_req_read_cmd_group(req) ||
+ nvmet_is_req_write_cmd_group(req)) &&
+ !nvmet_pr_find_registrant(pr, &ctrl->hostid))
+ status = NVME_SC_RESERVATION_CONFLICT | NVME_STATUS_DNR;
+ break;
+ default:
+ pr_warn("the reservation type is set wrong, type:%d\n",
+ holder->rtype);
+ break;
+ }
+
+unlock:
+ rcu_read_unlock();
+ if (status)
+ req->error_loc = offsetof(struct nvme_common_command, opcode);
+ return 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);
+}
projects / users / dwmw2 / linux.git / commitdiff