From: Mike Ximing Chen <mike.ximing.chen@intel.com>
To: linux-kernel@vger.kernel.org
Cc: arnd@arndb.de, gregkh@linuxfoundation.org,
dan.j.williams@intel.com, pierre-louis.bossart@linux.intel.com,
Gage Eads <gage.eads@intel.com>
Subject: [PATCH v9 09/20] dlb: add queue create, reset, get-depth ioctls
Date: Fri, 22 Jan 2021 13:01:27 -0600 [thread overview]
Message-ID: <20210122190138.7414-10-mike.ximing.chen@intel.com> (raw)
In-Reply-To: <20210122190138.7414-1-mike.ximing.chen@intel.com>
Add ioctl commands to create DLB queues and query their depth, and the
corresponding scheduling domain reset code to drain the queues when they
are no longer in use.
When a CPU enqueues a queue entry (QE) to DLB, the QE entry is sent to
a DLB queue. These queues hold queue entries (QEs) that have not yet
been scheduled to a destination port. The queue's depth is the number of
QEs residing in a queue.
Each queue supports multiple priority levels, and while a directed queue
has a 1:1 mapping with a directed port, load-balanced queues can be
configured with a set of load-balanced ports that software desires the
queue's QEs to be scheduled to.
For ease of review, this commit is limited to higher-level code including
the ioctl commands, request verification, and debug log messages. All
register access/configuration code will be included in a subsequent commit.
Signed-off-by: Gage Eads <gage.eads@intel.com>
Signed-off-by: Mike Ximing Chen <mike.ximing.chen@intel.com>
Reviewed-by: Magnus Karlsson <magnus.karlsson@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
---
drivers/misc/dlb/dlb_hw_types.h | 27 ++
drivers/misc/dlb/dlb_ioctl.c | 63 ++++
drivers/misc/dlb/dlb_main.c | 2 +
drivers/misc/dlb/dlb_main.h | 17 +
drivers/misc/dlb/dlb_pf_ops.c | 36 ++
drivers/misc/dlb/dlb_resource.c | 589 ++++++++++++++++++++++++++++++++
drivers/misc/dlb/dlb_resource.h | 20 ++
include/uapi/linux/dlb.h | 151 ++++++++
8 files changed, 905 insertions(+)
diff --git a/drivers/misc/dlb/dlb_hw_types.h b/drivers/misc/dlb/dlb_hw_types.h
index c486ea344292..d382c414e2b0 100644
--- a/drivers/misc/dlb/dlb_hw_types.h
+++ b/drivers/misc/dlb/dlb_hw_types.h
@@ -150,6 +150,33 @@ struct dlb_sn_group {
u32 id;
};
+static inline bool dlb_sn_group_full(struct dlb_sn_group *group)
+{
+ const u32 mask[] = {
+ 0x0000ffff, /* 64 SNs per queue */
+ 0x000000ff, /* 128 SNs per queue */
+ 0x0000000f, /* 256 SNs per queue */
+ 0x00000003, /* 512 SNs per queue */
+ 0x00000001}; /* 1024 SNs per queue */
+
+ return group->slot_use_bitmap == mask[group->mode];
+}
+
+static inline int dlb_sn_group_alloc_slot(struct dlb_sn_group *group)
+{
+ const u32 bound[] = {16, 8, 4, 2, 1};
+ u32 i;
+
+ for (i = 0; i < bound[group->mode]; i++) {
+ if (!(group->slot_use_bitmap & BIT(i))) {
+ group->slot_use_bitmap |= BIT(i);
+ return i;
+ }
+ }
+
+ return -1;
+}
+
static inline void
dlb_sn_group_free_slot(struct dlb_sn_group *group, int slot)
{
diff --git a/drivers/misc/dlb/dlb_ioctl.c b/drivers/misc/dlb/dlb_ioctl.c
index 75892966f061..0fc20b32f0cf 100644
--- a/drivers/misc/dlb/dlb_ioctl.c
+++ b/drivers/misc/dlb/dlb_ioctl.c
@@ -8,6 +8,69 @@
#include "dlb_main.h"
+/*
+ * The DLB domain ioctl callback template minimizes replication of boilerplate
+ * code to copy arguments, acquire and release the resource lock, and execute
+ * the command. The arguments and response structure name should have the
+ * format dlb_<lower_name>_args.
+ */
+#define DLB_DOMAIN_IOCTL_CALLBACK_TEMPLATE(lower_name) \
+static int dlb_domain_ioctl_##lower_name(struct dlb *dlb, \
+ struct dlb_domain *domain, \
+ unsigned long user_arg) \
+{ \
+ struct dlb_##lower_name##_args __user *uarg; \
+ struct dlb_cmd_response response = {0}; \
+ struct dlb_##lower_name##_args arg; \
+ int ret; \
+ \
+ uarg = (void __user *)user_arg; \
+ if (copy_from_user(&arg, uarg, sizeof(arg))) \
+ return -EFAULT; \
+ \
+ mutex_lock(&dlb->resource_mutex); \
+ \
+ ret = dlb->ops->lower_name(&dlb->hw, \
+ domain->id, \
+ &arg, \
+ &response); \
+ \
+ mutex_unlock(&dlb->resource_mutex); \
+ \
+ BUILD_BUG_ON(offsetof(typeof(arg), response) != 0); \
+ \
+ if (copy_to_user((void __user *)&uarg->response, \
+ &response, \
+ sizeof(response))) \
+ return -EFAULT; \
+ \
+ return ret; \
+}
+
+DLB_DOMAIN_IOCTL_CALLBACK_TEMPLATE(create_ldb_queue)
+DLB_DOMAIN_IOCTL_CALLBACK_TEMPLATE(create_dir_queue)
+DLB_DOMAIN_IOCTL_CALLBACK_TEMPLATE(get_ldb_queue_depth)
+DLB_DOMAIN_IOCTL_CALLBACK_TEMPLATE(get_dir_queue_depth)
+
+long dlb_domain_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
+{
+ struct dlb_domain *dom = f->private_data;
+ struct dlb *dlb = dom->dlb;
+
+ switch (cmd) {
+ case DLB_IOC_CREATE_LDB_QUEUE:
+ return dlb_domain_ioctl_create_ldb_queue(dlb, dom, arg);
+ case DLB_IOC_CREATE_DIR_QUEUE:
+ return dlb_domain_ioctl_create_dir_queue(dlb, dom, arg);
+ case DLB_IOC_GET_LDB_QUEUE_DEPTH:
+ return dlb_domain_ioctl_get_ldb_queue_depth(dlb, dom, arg);
+ case DLB_IOC_GET_DIR_QUEUE_DEPTH:
+ return dlb_domain_ioctl_get_dir_queue_depth(dlb, dom, arg);
+ default:
+ return -ENOTTY;
+ }
+}
+
/* [7:0]: device revision, [15:8]: device version */
#define DLB_SET_DEVICE_VERSION(ver, rev) (((ver) << 8) | (rev))
diff --git a/drivers/misc/dlb/dlb_main.c b/drivers/misc/dlb/dlb_main.c
index 5484d9aee02c..64915824ca03 100644
--- a/drivers/misc/dlb/dlb_main.c
+++ b/drivers/misc/dlb/dlb_main.c
@@ -185,6 +185,8 @@ static int dlb_domain_close(struct inode *i, struct file *f)
const struct file_operations dlb_domain_fops = {
.owner = THIS_MODULE,
.release = dlb_domain_close,
+ .unlocked_ioctl = dlb_domain_ioctl,
+ .compat_ioctl = compat_ptr_ioctl,
};
/**********************************/
diff --git a/drivers/misc/dlb/dlb_main.h b/drivers/misc/dlb/dlb_main.h
index ecfda11b297b..227630adf8ac 100644
--- a/drivers/misc/dlb/dlb_main.h
+++ b/drivers/misc/dlb/dlb_main.h
@@ -42,9 +42,25 @@ struct dlb_device_ops {
int (*create_sched_domain)(struct dlb_hw *hw,
struct dlb_create_sched_domain_args *args,
struct dlb_cmd_response *resp);
+ int (*create_ldb_queue)(struct dlb_hw *hw,
+ u32 domain_id,
+ struct dlb_create_ldb_queue_args *args,
+ struct dlb_cmd_response *resp);
+ int (*create_dir_queue)(struct dlb_hw *hw,
+ u32 domain_id,
+ struct dlb_create_dir_queue_args *args,
+ struct dlb_cmd_response *resp);
int (*get_num_resources)(struct dlb_hw *hw,
struct dlb_get_num_resources_args *args);
int (*reset_domain)(struct dlb_hw *hw, u32 domain_id);
+ int (*get_ldb_queue_depth)(struct dlb_hw *hw,
+ u32 domain_id,
+ struct dlb_get_ldb_queue_depth_args *args,
+ struct dlb_cmd_response *resp);
+ int (*get_dir_queue_depth)(struct dlb_hw *hw,
+ u32 domain_id,
+ struct dlb_get_dir_queue_depth_args *args,
+ struct dlb_cmd_response *resp);
};
extern struct dlb_device_ops dlb_pf_ops;
@@ -76,6 +92,7 @@ struct dlb {
/* Prototypes for dlb_ioctl.c */
long dlb_ioctl(struct file *f, unsigned int cmd, unsigned long arg);
+long dlb_domain_ioctl(struct file *f, unsigned int cmd, unsigned long arg);
int dlb_init_domain(struct dlb *dlb, u32 domain_id);
void dlb_free_domain(struct kref *kref);
diff --git a/drivers/misc/dlb/dlb_pf_ops.c b/drivers/misc/dlb/dlb_pf_ops.c
index 494a482368f6..32991c5f3366 100644
--- a/drivers/misc/dlb/dlb_pf_ops.c
+++ b/drivers/misc/dlb/dlb_pf_ops.c
@@ -114,6 +114,22 @@ static int dlb_pf_create_sched_domain(struct dlb_hw *hw,
return dlb_hw_create_sched_domain(hw, args, resp, false, 0);
}
+static int
+dlb_pf_create_ldb_queue(struct dlb_hw *hw, u32 id,
+ struct dlb_create_ldb_queue_args *args,
+ struct dlb_cmd_response *resp)
+{
+ return dlb_hw_create_ldb_queue(hw, id, args, resp, false, 0);
+}
+
+static int
+dlb_pf_create_dir_queue(struct dlb_hw *hw, u32 id,
+ struct dlb_create_dir_queue_args *args,
+ struct dlb_cmd_response *resp)
+{
+ return dlb_hw_create_dir_queue(hw, id, args, resp, false, 0);
+}
+
static int dlb_pf_get_num_resources(struct dlb_hw *hw,
struct dlb_get_num_resources_args *args)
{
@@ -126,6 +142,22 @@ dlb_pf_reset_domain(struct dlb_hw *hw, u32 id)
return dlb_reset_domain(hw, id, false, 0);
}
+static int
+dlb_pf_get_ldb_queue_depth(struct dlb_hw *hw, u32 id,
+ struct dlb_get_ldb_queue_depth_args *args,
+ struct dlb_cmd_response *resp)
+{
+ return dlb_hw_get_ldb_queue_depth(hw, id, args, resp, false, 0);
+}
+
+static int
+dlb_pf_get_dir_queue_depth(struct dlb_hw *hw, u32 id,
+ struct dlb_get_dir_queue_depth_args *args,
+ struct dlb_cmd_response *resp)
+{
+ return dlb_hw_get_dir_queue_depth(hw, id, args, resp, false, 0);
+}
+
/********************************/
/****** DLB PF Device Ops ******/
/********************************/
@@ -137,6 +169,10 @@ struct dlb_device_ops dlb_pf_ops = {
.enable_pm = dlb_pf_enable_pm,
.wait_for_device_ready = dlb_pf_wait_for_device_ready,
.create_sched_domain = dlb_pf_create_sched_domain,
+ .create_ldb_queue = dlb_pf_create_ldb_queue,
+ .create_dir_queue = dlb_pf_create_dir_queue,
.get_num_resources = dlb_pf_get_num_resources,
.reset_domain = dlb_pf_reset_domain,
+ .get_ldb_queue_depth = dlb_pf_get_ldb_queue_depth,
+ .get_dir_queue_depth = dlb_pf_get_dir_queue_depth,
};
diff --git a/drivers/misc/dlb/dlb_resource.c b/drivers/misc/dlb/dlb_resource.c
index 26b7d9ea94e3..b36f14a661fa 100644
--- a/drivers/misc/dlb/dlb_resource.c
+++ b/drivers/misc/dlb/dlb_resource.c
@@ -224,6 +224,40 @@ static struct dlb_hw_domain *dlb_get_domain_from_id(struct dlb_hw *hw, u32 id,
return NULL;
}
+static struct dlb_dir_pq_pair *
+dlb_get_domain_used_dir_pq(u32 id, bool vdev_req, struct dlb_hw_domain *domain)
+{
+ struct dlb_dir_pq_pair *port;
+
+ if (id >= DLB_MAX_NUM_DIR_PORTS)
+ return NULL;
+
+ list_for_each_entry(port, &domain->used_dir_pq_pairs, domain_list) {
+ if ((!vdev_req && port->id.phys_id == id) ||
+ (vdev_req && port->id.virt_id == id))
+ return port;
+ }
+
+ return NULL;
+}
+
+static struct dlb_ldb_queue *
+dlb_get_domain_ldb_queue(u32 id, bool vdev_req, struct dlb_hw_domain *domain)
+{
+ struct dlb_ldb_queue *queue;
+
+ if (id >= DLB_MAX_NUM_LDB_QUEUES)
+ return NULL;
+
+ list_for_each_entry(queue, &domain->used_ldb_queues, domain_list) {
+ if ((!vdev_req && queue->id.phys_id == id) ||
+ (vdev_req && queue->id.virt_id == id))
+ return queue;
+ }
+
+ return NULL;
+}
+
static int dlb_attach_ldb_queues(struct dlb_hw *hw,
struct dlb_function_resources *rsrcs,
struct dlb_hw_domain *domain, u32 num_queues,
@@ -660,6 +694,156 @@ dlb_verify_create_sched_dom_args(struct dlb_function_resources *rsrcs,
return 0;
}
+static int
+dlb_verify_create_ldb_queue_args(struct dlb_hw *hw, u32 domain_id,
+ struct dlb_create_ldb_queue_args *args,
+ struct dlb_cmd_response *resp,
+ bool vdev_req, unsigned int vdev_id,
+ struct dlb_hw_domain **out_domain,
+ struct dlb_ldb_queue **out_queue)
+{
+ struct dlb_hw_domain *domain;
+ struct dlb_ldb_queue *queue;
+ int i;
+
+ domain = dlb_get_domain_from_id(hw, domain_id, vdev_req, vdev_id);
+
+ if (!domain) {
+ resp->status = DLB_ST_INVALID_DOMAIN_ID;
+ return -EINVAL;
+ }
+
+ if (!domain->configured) {
+ resp->status = DLB_ST_DOMAIN_NOT_CONFIGURED;
+ return -EINVAL;
+ }
+
+ if (domain->started) {
+ resp->status = DLB_ST_DOMAIN_STARTED;
+ return -EINVAL;
+ }
+
+ queue = list_first_entry_or_null(&domain->avail_ldb_queues,
+ typeof(*queue), domain_list);
+ if (!queue) {
+ resp->status = DLB_ST_LDB_QUEUES_UNAVAILABLE;
+ return -EINVAL;
+ }
+
+ if (args->num_sequence_numbers) {
+ for (i = 0; i < DLB_MAX_NUM_SEQUENCE_NUMBER_GROUPS; i++) {
+ struct dlb_sn_group *group = &hw->rsrcs.sn_groups[i];
+
+ if (group->sequence_numbers_per_queue ==
+ args->num_sequence_numbers &&
+ !dlb_sn_group_full(group))
+ break;
+ }
+
+ if (i == DLB_MAX_NUM_SEQUENCE_NUMBER_GROUPS) {
+ resp->status = DLB_ST_SEQUENCE_NUMBERS_UNAVAILABLE;
+ return -EINVAL;
+ }
+ }
+
+ if (args->num_qid_inflights > 4096) {
+ resp->status = DLB_ST_INVALID_QID_INFLIGHT_ALLOCATION;
+ return -EINVAL;
+ }
+
+ /* Inflights must be <= number of sequence numbers if ordered */
+ if (args->num_sequence_numbers != 0 &&
+ args->num_qid_inflights > args->num_sequence_numbers) {
+ resp->status = DLB_ST_INVALID_QID_INFLIGHT_ALLOCATION;
+ return -EINVAL;
+ }
+
+ if (domain->num_avail_aqed_entries < args->num_atomic_inflights) {
+ resp->status = DLB_ST_ATOMIC_INFLIGHTS_UNAVAILABLE;
+ return -EINVAL;
+ }
+
+ if (args->num_atomic_inflights &&
+ args->lock_id_comp_level != 0 &&
+ args->lock_id_comp_level != 64 &&
+ args->lock_id_comp_level != 128 &&
+ args->lock_id_comp_level != 256 &&
+ args->lock_id_comp_level != 512 &&
+ args->lock_id_comp_level != 1024 &&
+ args->lock_id_comp_level != 2048 &&
+ args->lock_id_comp_level != 4096 &&
+ args->lock_id_comp_level != 65536) {
+ resp->status = DLB_ST_INVALID_LOCK_ID_COMP_LEVEL;
+ return -EINVAL;
+ }
+
+ *out_domain = domain;
+ *out_queue = queue;
+
+ return 0;
+}
+
+static int
+dlb_verify_create_dir_queue_args(struct dlb_hw *hw, u32 domain_id,
+ struct dlb_create_dir_queue_args *args,
+ struct dlb_cmd_response *resp,
+ bool vdev_req, unsigned int vdev_id,
+ struct dlb_hw_domain **out_domain,
+ struct dlb_dir_pq_pair **out_queue)
+{
+ struct dlb_hw_domain *domain;
+ struct dlb_dir_pq_pair *pq;
+
+ domain = dlb_get_domain_from_id(hw, domain_id, vdev_req, vdev_id);
+
+ if (!domain) {
+ resp->status = DLB_ST_INVALID_DOMAIN_ID;
+ return -EINVAL;
+ }
+
+ if (!domain->configured) {
+ resp->status = DLB_ST_DOMAIN_NOT_CONFIGURED;
+ return -EINVAL;
+ }
+
+ if (domain->started) {
+ resp->status = DLB_ST_DOMAIN_STARTED;
+ return -EINVAL;
+ }
+
+ /*
+ * If the user claims the port is already configured, validate the port
+ * ID, its domain, and whether the port is configured.
+ */
+ if (args->port_id != -1) {
+ pq = dlb_get_domain_used_dir_pq(args->port_id,
+ vdev_req,
+ domain);
+
+ if (!pq || pq->domain_id.phys_id != domain->id.phys_id ||
+ !pq->port_configured) {
+ resp->status = DLB_ST_INVALID_PORT_ID;
+ return -EINVAL;
+ }
+ } else {
+ /*
+ * If the queue's port is not configured, validate that a free
+ * port-queue pair is available.
+ */
+ pq = list_first_entry_or_null(&domain->avail_dir_pq_pairs,
+ typeof(*pq), domain_list);
+ if (!pq) {
+ resp->status = DLB_ST_DIR_QUEUES_UNAVAILABLE;
+ return -EINVAL;
+ }
+ }
+
+ *out_domain = domain;
+ *out_queue = pq;
+
+ return 0;
+}
+
static void dlb_configure_domain_credits(struct dlb_hw *hw,
struct dlb_hw_domain *domain)
{
@@ -725,6 +909,68 @@ dlb_domain_attach_resources(struct dlb_hw *hw,
return 0;
}
+static int
+dlb_ldb_queue_attach_to_sn_group(struct dlb_hw *hw,
+ struct dlb_ldb_queue *queue,
+ struct dlb_create_ldb_queue_args *args)
+{
+ int slot = -1;
+ int i;
+
+ queue->sn_cfg_valid = false;
+
+ if (args->num_sequence_numbers == 0)
+ return 0;
+
+ for (i = 0; i < DLB_MAX_NUM_SEQUENCE_NUMBER_GROUPS; i++) {
+ struct dlb_sn_group *group = &hw->rsrcs.sn_groups[i];
+
+ if (group->sequence_numbers_per_queue ==
+ args->num_sequence_numbers &&
+ !dlb_sn_group_full(group)) {
+ slot = dlb_sn_group_alloc_slot(group);
+ if (slot >= 0)
+ break;
+ }
+ }
+
+ if (slot == -1) {
+ DLB_HW_ERR(hw,
+ "[%s():%d] Internal error: no sequence number slots available\n",
+ __func__, __LINE__);
+ return -EFAULT;
+ }
+
+ queue->sn_cfg_valid = true;
+ queue->sn_group = i;
+ queue->sn_slot = slot;
+ return 0;
+}
+
+static int
+dlb_ldb_queue_attach_resources(struct dlb_hw *hw,
+ struct dlb_hw_domain *domain,
+ struct dlb_ldb_queue *queue,
+ struct dlb_create_ldb_queue_args *args)
+{
+ int ret;
+
+ ret = dlb_ldb_queue_attach_to_sn_group(hw, queue, args);
+ if (ret)
+ return ret;
+
+ /* Attach QID inflights */
+ queue->num_qid_inflights = args->num_qid_inflights;
+
+ /* Attach atomic inflights */
+ queue->aqed_limit = args->num_atomic_inflights;
+
+ domain->num_avail_aqed_entries -= args->num_atomic_inflights;
+ domain->num_used_aqed_entries += args->num_atomic_inflights;
+
+ return 0;
+}
+
static void
dlb_log_create_sched_domain_args(struct dlb_hw *hw,
struct dlb_create_sched_domain_args *args,
@@ -828,6 +1074,172 @@ int dlb_hw_create_sched_domain(struct dlb_hw *hw,
return 0;
}
+static void
+dlb_log_create_ldb_queue_args(struct dlb_hw *hw, u32 domain_id,
+ struct dlb_create_ldb_queue_args *args,
+ bool vdev_req, unsigned int vdev_id)
+{
+ DLB_HW_DBG(hw, "DLB create load-balanced queue arguments:\n");
+ if (vdev_req)
+ DLB_HW_DBG(hw, "(Request from vdev %d)\n", vdev_id);
+ DLB_HW_DBG(hw, "\tDomain ID: %d\n",
+ domain_id);
+ DLB_HW_DBG(hw, "\tNumber of sequence numbers: %d\n",
+ args->num_sequence_numbers);
+ DLB_HW_DBG(hw, "\tNumber of QID inflights: %d\n",
+ args->num_qid_inflights);
+ DLB_HW_DBG(hw, "\tNumber of ATM inflights: %d\n",
+ args->num_atomic_inflights);
+}
+
+/**
+ * dlb_hw_create_ldb_queue() - create a load-balanced queue
+ * @hw: dlb_hw handle for a particular device.
+ * @domain_id: domain ID.
+ * @args: queue creation arguments.
+ * @resp: response structure.
+ * @vdev_req: indicates whether this request came from a vdev.
+ * @vdev_id: If vdev_req is true, this contains the vdev's ID.
+ *
+ * This function creates a load-balanced queue.
+ *
+ * A vdev can be either an SR-IOV virtual function or a Scalable IOV virtual
+ * device.
+ *
+ * Return:
+ * Returns 0 upon success, < 0 otherwise. If an error occurs, resp->status is
+ * assigned a detailed error code from enum dlb_error. If successful, resp->id
+ * contains the queue ID.
+ *
+ * resp->id contains a virtual ID if vdev_req is true.
+ *
+ * Errors:
+ * EINVAL - A requested resource is unavailable, the domain is not configured,
+ * the domain has already been started, or the requested queue name is
+ * already in use.
+ * EFAULT - Internal error (resp->status not set).
+ */
+int dlb_hw_create_ldb_queue(struct dlb_hw *hw, u32 domain_id,
+ struct dlb_create_ldb_queue_args *args,
+ struct dlb_cmd_response *resp,
+ bool vdev_req, unsigned int vdev_id)
+{
+ struct dlb_hw_domain *domain;
+ struct dlb_ldb_queue *queue;
+ int ret;
+
+ dlb_log_create_ldb_queue_args(hw, domain_id, args, vdev_req, vdev_id);
+
+ /*
+ * Verify that hardware resources are available before attempting to
+ * satisfy the request. This simplifies the error unwinding code.
+ */
+ ret = dlb_verify_create_ldb_queue_args(hw, domain_id, args, resp,
+ vdev_req, vdev_id, &domain, &queue);
+ if (ret)
+ return ret;
+
+ ret = dlb_ldb_queue_attach_resources(hw, domain, queue, args);
+ if (ret) {
+ DLB_HW_ERR(hw,
+ "[%s():%d] Internal error: failed to attach the ldb queue resources\n",
+ __func__, __LINE__);
+ return ret;
+ }
+
+ queue->num_mappings = 0;
+
+ queue->configured = true;
+
+ /*
+ * Configuration succeeded, so move the resource from the 'avail' to
+ * the 'used' list.
+ */
+ list_del(&queue->domain_list);
+
+ list_add(&queue->domain_list, &domain->used_ldb_queues);
+
+ resp->status = 0;
+ resp->id = (vdev_req) ? queue->id.virt_id : queue->id.phys_id;
+
+ return 0;
+}
+
+static void
+dlb_log_create_dir_queue_args(struct dlb_hw *hw, u32 domain_id,
+ struct dlb_create_dir_queue_args *args,
+ bool vdev_req, unsigned int vdev_id)
+{
+ DLB_HW_DBG(hw, "DLB create directed queue arguments:\n");
+ if (vdev_req)
+ DLB_HW_DBG(hw, "(Request from vdev %d)\n", vdev_id);
+ DLB_HW_DBG(hw, "\tDomain ID: %d\n", domain_id);
+ DLB_HW_DBG(hw, "\tPort ID: %d\n", args->port_id);
+}
+
+/**
+ * dlb_hw_create_dir_queue() - create a directed queue
+ * @hw: dlb_hw handle for a particular device.
+ * @domain_id: domain ID.
+ * @args: queue creation arguments.
+ * @resp: response structure.
+ * @vdev_req: indicates whether this request came from a vdev.
+ * @vdev_id: If vdev_req is true, this contains the vdev's ID.
+ *
+ * This function creates a directed queue.
+ *
+ * A vdev can be either an SR-IOV virtual function or a Scalable IOV virtual
+ * device.
+ *
+ * Return:
+ * Returns 0 upon success, < 0 otherwise. If an error occurs, resp->status is
+ * assigned a detailed error code from enum dlb_error. If successful, resp->id
+ * contains the queue ID.
+ *
+ * resp->id contains a virtual ID if vdev_req is true.
+ *
+ * Errors:
+ * EINVAL - A requested resource is unavailable, the domain is not configured,
+ * or the domain has already been started.
+ * EFAULT - Internal error (resp->status not set).
+ */
+int dlb_hw_create_dir_queue(struct dlb_hw *hw, u32 domain_id,
+ struct dlb_create_dir_queue_args *args,
+ struct dlb_cmd_response *resp,
+ bool vdev_req, unsigned int vdev_id)
+{
+ struct dlb_dir_pq_pair *queue;
+ struct dlb_hw_domain *domain;
+ int ret;
+
+ dlb_log_create_dir_queue_args(hw, domain_id, args, vdev_req, vdev_id);
+
+ /*
+ * Verify that hardware resources are available before attempting to
+ * satisfy the request. This simplifies the error unwinding code.
+ */
+ ret = dlb_verify_create_dir_queue_args(hw, domain_id, args, resp,
+ vdev_req, vdev_id, &domain, &queue);
+ if (ret)
+ return ret;
+
+ /*
+ * Configuration succeeded, so move the resource from the 'avail' to
+ * the 'used' list (if it's not already there).
+ */
+ if (args->port_id == -1) {
+ list_del(&queue->domain_list);
+
+ list_add(&queue->domain_list, &domain->used_dir_pq_pairs);
+ }
+
+ resp->status = 0;
+
+ resp->id = (vdev_req) ? queue->id.virt_id : queue->id.phys_id;
+
+ return 0;
+}
+
static int dlb_domain_reset_software_state(struct dlb_hw *hw,
struct dlb_hw_domain *domain)
{
@@ -973,6 +1385,151 @@ static int dlb_domain_reset_software_state(struct dlb_hw *hw,
return 0;
}
+static void dlb_log_get_dir_queue_depth(struct dlb_hw *hw, u32 domain_id,
+ u32 queue_id, bool vdev_req,
+ unsigned int vf_id)
+{
+ DLB_HW_DBG(hw, "DLB get directed queue depth:\n");
+ if (vdev_req)
+ DLB_HW_DBG(hw, "(Request from VF %d)\n", vf_id);
+ DLB_HW_DBG(hw, "\tDomain ID: %d\n", domain_id);
+ DLB_HW_DBG(hw, "\tQueue ID: %d\n", queue_id);
+}
+
+/**
+ * dlb_hw_get_dir_queue_depth() - returns the depth of a directed queue
+ * @hw: dlb_hw handle for a particular device.
+ * @domain_id: domain ID.
+ * @args: queue depth args
+ * @resp: response structure.
+ * @vdev_req: indicates whether this request came from a vdev.
+ * @vdev_id: If vdev_req is true, this contains the vdev's ID.
+ *
+ * This function returns the depth of a directed queue.
+ *
+ * A vdev can be either an SR-IOV virtual function or a Scalable IOV virtual
+ * device.
+ *
+ * Return:
+ * Returns 0 upon success, < 0 otherwise. If an error occurs, resp->status is
+ * assigned a detailed error code from enum dlb_error. If successful, resp->id
+ * contains the depth.
+ *
+ * Errors:
+ * EINVAL - Invalid domain ID or queue ID.
+ */
+int dlb_hw_get_dir_queue_depth(struct dlb_hw *hw, u32 domain_id,
+ struct dlb_get_dir_queue_depth_args *args,
+ struct dlb_cmd_response *resp,
+ bool vdev_req, unsigned int vdev_id)
+{
+ struct dlb_dir_pq_pair *queue;
+ struct dlb_hw_domain *domain;
+ int id;
+
+ id = domain_id;
+
+ dlb_log_get_dir_queue_depth(hw, domain_id, args->queue_id,
+ vdev_req, vdev_id);
+
+ domain = dlb_get_domain_from_id(hw, id, vdev_req, vdev_id);
+ if (!domain) {
+ resp->status = DLB_ST_INVALID_DOMAIN_ID;
+ return -EINVAL;
+ }
+
+ id = args->queue_id;
+
+ queue = dlb_get_domain_used_dir_pq(id, vdev_req, domain);
+ if (!queue) {
+ resp->status = DLB_ST_INVALID_QID;
+ return -EINVAL;
+ }
+
+ resp->id = 0;
+
+ return 0;
+}
+
+static u32 dlb_ldb_queue_depth(struct dlb_hw *hw, struct dlb_ldb_queue *queue)
+{
+ u32 aqed, ldb, atm;
+
+ aqed = DLB_CSR_RD(hw, LSP_QID_AQED_ACTIVE_CNT(queue->id.phys_id));
+ ldb = DLB_CSR_RD(hw, LSP_QID_LDB_ENQUEUE_CNT(queue->id.phys_id));
+ atm = DLB_CSR_RD(hw, LSP_QID_ATM_ACTIVE(queue->id.phys_id));
+
+ return BITS_GET(aqed, LSP_QID_AQED_ACTIVE_CNT_COUNT)
+ + BITS_GET(ldb, LSP_QID_LDB_ENQUEUE_CNT_COUNT)
+ + BITS_GET(atm, LSP_QID_ATM_ACTIVE_COUNT);
+}
+
+static bool dlb_ldb_queue_is_empty(struct dlb_hw *hw, struct dlb_ldb_queue *queue)
+{
+ return dlb_ldb_queue_depth(hw, queue) == 0;
+}
+
+static void dlb_log_get_ldb_queue_depth(struct dlb_hw *hw, u32 domain_id,
+ u32 queue_id, bool vdev_req,
+ unsigned int vf_id)
+{
+ DLB_HW_DBG(hw, "DLB get load-balanced queue depth:\n");
+ if (vdev_req)
+ DLB_HW_DBG(hw, "(Request from VF %d)\n", vf_id);
+ DLB_HW_DBG(hw, "\tDomain ID: %d\n", domain_id);
+ DLB_HW_DBG(hw, "\tQueue ID: %d\n", queue_id);
+}
+
+/**
+ * dlb_hw_get_ldb_queue_depth() - returns the depth of a load-balanced queue
+ * @hw: dlb_hw handle for a particular device.
+ * @domain_id: domain ID.
+ * @args: queue depth args
+ * @resp: response structure.
+ * @vdev_req: indicates whether this request came from a vdev.
+ * @vdev_id: If vdev_req is true, this contains the vdev's ID.
+ *
+ * This function returns the depth of a load-balanced queue.
+ *
+ * A vdev can be either an SR-IOV virtual function or a Scalable IOV virtual
+ * device.
+ *
+ * Return:
+ * Returns 0 upon success, < 0 otherwise. If an error occurs, resp->status is
+ * assigned a detailed error code from enum dlb_error. If successful, resp->id
+ * contains the depth.
+ *
+ * Errors:
+ * EINVAL - Invalid domain ID or queue ID.
+ */
+int dlb_hw_get_ldb_queue_depth(struct dlb_hw *hw, u32 domain_id,
+ struct dlb_get_ldb_queue_depth_args *args,
+ struct dlb_cmd_response *resp,
+ bool vdev_req, unsigned int vdev_id)
+{
+ struct dlb_hw_domain *domain;
+ struct dlb_ldb_queue *queue;
+
+ dlb_log_get_ldb_queue_depth(hw, domain_id, args->queue_id,
+ vdev_req, vdev_id);
+
+ domain = dlb_get_domain_from_id(hw, domain_id, vdev_req, vdev_id);
+ if (!domain) {
+ resp->status = DLB_ST_INVALID_DOMAIN_ID;
+ return -EINVAL;
+ }
+
+ queue = dlb_get_domain_ldb_queue(args->queue_id, vdev_req, domain);
+ if (!queue) {
+ resp->status = DLB_ST_INVALID_QID;
+ return -EINVAL;
+ }
+
+ resp->id = 0;
+
+ return 0;
+}
+
static void __dlb_domain_reset_ldb_port_registers(struct dlb_hw *hw,
struct dlb_ldb_port *port)
{
@@ -1337,6 +1894,27 @@ static void dlb_domain_reset_dir_queue_registers(struct dlb_hw *hw,
}
}
+static int dlb_domain_verify_reset_success(struct dlb_hw *hw,
+ struct dlb_hw_domain *domain)
+{
+ struct dlb_ldb_queue *queue;
+
+ /*
+ * Confirm that all the domain's queue's inflight counts and AQED
+ * active counts are 0.
+ */
+ list_for_each_entry(queue, &domain->used_ldb_queues, domain_list) {
+ if (!dlb_ldb_queue_is_empty(hw, queue)) {
+ DLB_HW_ERR(hw,
+ "[%s()] Internal error: failed to empty ldb queue %d\n",
+ __func__, queue->id.phys_id);
+ return -EFAULT;
+ }
+ }
+
+ return 0;
+}
+
static void dlb_domain_reset_registers(struct dlb_hw *hw,
struct dlb_hw_domain *domain)
{
@@ -1395,6 +1973,7 @@ int dlb_reset_domain(struct dlb_hw *hw, u32 domain_id, bool vdev_req,
unsigned int vdev_id)
{
struct dlb_hw_domain *domain;
+ int ret;
dlb_log_reset_domain(hw, domain_id, vdev_req, vdev_id);
@@ -1403,6 +1982,16 @@ int dlb_reset_domain(struct dlb_hw *hw, u32 domain_id, bool vdev_req,
if (!domain || !domain->configured)
return -EINVAL;
+ /*
+ * For each queue owned by this domain, disable its write permissions to
+ * cause any traffic sent to it to be dropped. Well-behaved software
+ * should not be sending QEs at this point.
+ */
+
+ ret = dlb_domain_verify_reset_success(hw, domain);
+ if (ret)
+ return ret;
+
/* Reset the QID and port state. */
dlb_domain_reset_registers(hw, domain);
diff --git a/drivers/misc/dlb/dlb_resource.h b/drivers/misc/dlb/dlb_resource.h
index 8c50f449cb9b..50e674e46dbb 100644
--- a/drivers/misc/dlb/dlb_resource.h
+++ b/drivers/misc/dlb/dlb_resource.h
@@ -19,6 +19,16 @@ int dlb_hw_create_sched_domain(struct dlb_hw *hw,
struct dlb_cmd_response *resp,
bool vdev_req, unsigned int vdev_id);
+int dlb_hw_create_ldb_queue(struct dlb_hw *hw, u32 domain_id,
+ struct dlb_create_ldb_queue_args *args,
+ struct dlb_cmd_response *resp,
+ bool vdev_req, unsigned int vdev_id);
+
+int dlb_hw_create_dir_queue(struct dlb_hw *hw, u32 domain_id,
+ struct dlb_create_dir_queue_args *args,
+ struct dlb_cmd_response *resp,
+ bool vdev_req, unsigned int vdev_id);
+
int dlb_reset_domain(struct dlb_hw *hw, u32 domain_id, bool vdev_req,
unsigned int vdev_id);
@@ -28,4 +38,14 @@ int dlb_hw_get_num_resources(struct dlb_hw *hw,
void dlb_clr_pmcsr_disable(struct dlb_hw *hw);
+int dlb_hw_get_ldb_queue_depth(struct dlb_hw *hw, u32 domain_id,
+ struct dlb_get_ldb_queue_depth_args *args,
+ struct dlb_cmd_response *resp,
+ bool vdev_req, unsigned int vdev_id);
+
+int dlb_hw_get_dir_queue_depth(struct dlb_hw *hw, u32 domain_id,
+ struct dlb_get_dir_queue_depth_args *args,
+ struct dlb_cmd_response *resp,
+ bool vdev_req, unsigned int vdev_id);
+
#endif /* __DLB_RESOURCE_H */
diff --git a/include/uapi/linux/dlb.h b/include/uapi/linux/dlb.h
index 26fc7d77019c..1141b059beb9 100644
--- a/include/uapi/linux/dlb.h
+++ b/include/uapi/linux/dlb.h
@@ -19,6 +19,15 @@ enum dlb_error {
DLB_ST_HIST_LIST_ENTRIES_UNAVAILABLE,
DLB_ST_LDB_PORT_REQUIRED_FOR_LDB_QUEUES,
DLB_ST_DOMAIN_RESET_FAILED,
+ DLB_ST_INVALID_DOMAIN_ID,
+ DLB_ST_INVALID_QID_INFLIGHT_ALLOCATION,
+ DLB_ST_INVALID_LDB_QUEUE_ID,
+ DLB_ST_DOMAIN_NOT_CONFIGURED,
+ DLB_ST_INVALID_QID,
+ DLB_ST_DOMAIN_STARTED,
+ DLB_ST_DIR_QUEUES_UNAVAILABLE,
+ DLB_ST_INVALID_PORT_ID,
+ DLB_ST_INVALID_LOCK_ID_COMP_LEVEL,
};
struct dlb_cmd_response {
@@ -160,6 +169,132 @@ enum dlb_user_interface_commands {
NUM_DLB_CMD,
};
+/*********************************/
+/* 'domain' device file commands */
+/*********************************/
+
+/*
+ * DLB_DOMAIN_CMD_CREATE_LDB_QUEUE: Configure a load-balanced queue.
+ *
+ * Output parameters:
+ * @response.status: Detailed error code. In certain cases, such as if the
+ * ioctl request arg is invalid, the driver won't set status.
+ * @response.id: Queue ID.
+ *
+ * Input parameters:
+ * @num_atomic_inflights: This specifies the amount of temporary atomic QE
+ * storage for this queue. If zero, the queue will not support atomic
+ * scheduling.
+ * @num_sequence_numbers: This specifies the number of sequence numbers used
+ * by this queue. If zero, the queue will not support ordered scheduling.
+ * If non-zero, the queue will not support unordered scheduling.
+ * @num_qid_inflights: The maximum number of QEs that can be inflight
+ * (scheduled to a CQ but not completed) at any time. If
+ * num_sequence_numbers is non-zero, num_qid_inflights must be set equal
+ * to num_sequence_numbers.
+ * @lock_id_comp_level: Lock ID compression level. Specifies the number of
+ * unique lock IDs the queue should compress down to. Valid compression
+ * levels: 0, 64, 128, 256, 512, 1k, 2k, 4k, 64k. If lock_id_comp_level is
+ * 0, the queue won't compress its lock IDs.
+ * @depth_threshold: DLB sets two bits in the received QE to indicate the
+ * depth of the queue relative to the threshold before scheduling the
+ * QE to a CQ:
+ * - 2’b11: depth > threshold
+ * - 2’b10: threshold >= depth > 0.75 * threshold
+ * - 2’b01: 0.75 * threshold >= depth > 0.5 * threshold
+ * - 2’b00: depth <= 0.5 * threshold
+ * @padding0: Reserved for future use.
+ */
+struct dlb_create_ldb_queue_args {
+ /* Output parameters */
+ struct dlb_cmd_response response;
+ /* Input parameters */
+ __u32 num_sequence_numbers;
+ __u32 num_qid_inflights;
+ __u32 num_atomic_inflights;
+ __u32 lock_id_comp_level;
+ __u32 depth_threshold;
+ __u32 padding0;
+};
+
+/*
+ * DLB_DOMAIN_CMD_CREATE_DIR_QUEUE: Configure a directed queue.
+ *
+ * Output parameters:
+ * @response.status: Detailed error code. In certain cases, such as if the
+ * ioctl request arg is invalid, the driver won't set status.
+ * @response.id: Queue ID.
+ *
+ * Input parameters:
+ * @port_id: Port ID. If the corresponding directed port is already created,
+ * specify its ID here. Else this argument must be 0xFFFFFFFF to indicate
+ * that the queue is being created before the port.
+ * @depth_threshold: DLB sets two bits in the received QE to indicate the
+ * depth of the queue relative to the threshold before scheduling the
+ * QE to a CQ:
+ * - 2’b11: depth > threshold
+ * - 2’b10: threshold >= depth > 0.75 * threshold
+ * - 2’b01: 0.75 * threshold >= depth > 0.5 * threshold
+ * - 2’b00: depth <= 0.5 * threshold
+ */
+struct dlb_create_dir_queue_args {
+ /* Output parameters */
+ struct dlb_cmd_response response;
+ /* Input parameters */
+ __s32 port_id;
+ __u32 depth_threshold;
+};
+
+/*
+ * DLB_DOMAIN_CMD_GET_LDB_QUEUE_DEPTH: Get a load-balanced queue's depth.
+ *
+ * Output parameters:
+ * @response.status: Detailed error code. In certain cases, such as if the
+ * ioctl request arg is invalid, the driver won't set status.
+ * @response.id: queue depth.
+ *
+ * Input parameters:
+ * @queue_id: The load-balanced queue ID.
+ * @padding0: Reserved for future use.
+ */
+struct dlb_get_ldb_queue_depth_args {
+ /* Output parameters */
+ struct dlb_cmd_response response;
+ /* Input parameters */
+ __u32 queue_id;
+ __u32 padding0;
+};
+
+/*
+ * DLB_DOMAIN_CMD_DIR_QUEUE_DEPTH: Get a directed queue's depth.
+ *
+ * Output parameters:
+ * @response.status: Detailed error code. In certain cases, such as if the
+ * ioctl request arg is invalid, the driver won't set status.
+ * @response.id: queue depth.
+ *
+ * Input parameters:
+ * @queue_id: The directed queue ID.
+ * @padding0: Reserved for future use.
+ */
+struct dlb_get_dir_queue_depth_args {
+ /* Output parameters */
+ struct dlb_cmd_response response;
+ /* Input parameters */
+ __u32 queue_id;
+ __u32 padding0;
+};
+
+enum dlb_domain_user_interface_commands {
+ DLB_DOMAIN_CMD_CREATE_LDB_QUEUE,
+ DLB_DOMAIN_CMD_CREATE_DIR_QUEUE,
+ DLB_DOMAIN_CMD_GET_LDB_QUEUE_DEPTH,
+ DLB_DOMAIN_CMD_GET_DIR_QUEUE_DEPTH,
+
+ /* NUM_DLB_DOMAIN_CMD must be last */
+ NUM_DLB_DOMAIN_CMD,
+};
+
/********************/
/* dlb ioctl codes */
/********************/
@@ -178,5 +313,21 @@ enum dlb_user_interface_commands {
_IOR(DLB_IOC_MAGIC, \
DLB_CMD_GET_NUM_RESOURCES, \
struct dlb_get_num_resources_args)
+#define DLB_IOC_CREATE_LDB_QUEUE \
+ _IOWR(DLB_IOC_MAGIC, \
+ DLB_DOMAIN_CMD_CREATE_LDB_QUEUE, \
+ struct dlb_create_ldb_queue_args)
+#define DLB_IOC_CREATE_DIR_QUEUE \
+ _IOWR(DLB_IOC_MAGIC, \
+ DLB_DOMAIN_CMD_CREATE_DIR_QUEUE, \
+ struct dlb_create_dir_queue_args)
+#define DLB_IOC_GET_LDB_QUEUE_DEPTH \
+ _IOWR(DLB_IOC_MAGIC, \
+ DLB_DOMAIN_CMD_GET_LDB_QUEUE_DEPTH, \
+ struct dlb_get_ldb_queue_depth_args)
+#define DLB_IOC_GET_DIR_QUEUE_DEPTH \
+ _IOWR(DLB_IOC_MAGIC, \
+ DLB_DOMAIN_CMD_GET_DIR_QUEUE_DEPTH, \
+ struct dlb_get_dir_queue_depth_args)
#endif /* __DLB_H */
--
2.17.1
next prev parent reply other threads:[~2021-01-22 19:35 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-22 19:01 [PATCH v9 00/20] dlb: introduce DLB device driver Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 01/20] dlb: add skeleton for DLB driver Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 02/20] dlb: initialize device Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 03/20] dlb: add resource and device initialization Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 04/20] dlb: add device ioctl layer and first three ioctls Mike Ximing Chen
2021-01-27 1:25 ` kernel test robot
2021-01-27 12:29 ` Greg KH
2021-01-27 13:59 ` Chen, Mike Ximing
2021-01-27 14:03 ` Greg KH
2021-01-27 23:15 ` Chen, Mike Ximing
2021-01-22 19:01 ` [PATCH v9 05/20] dlb: add scheduling domain configuration Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 06/20] dlb: add domain software reset Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 07/20] dlb: add low-level register reset operations Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 08/20] dlb: add runtime power-management support Mike Ximing Chen
2021-01-22 19:01 ` Mike Ximing Chen [this message]
2021-01-22 19:01 ` [PATCH v9 10/20] dlb: add register operations for queue management Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 11/20] dlb: add ioctl to configure ports and query poll mode Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 12/20] dlb: add register operations for port management Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 13/20] dlb: add port mmap support Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 14/20] dlb: add start domain ioctl Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 15/20] dlb: add queue map, unmap, and pending unmap operations Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 16/20] dlb: add port map/unmap state machine Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 17/20] dlb: add static queue map register operations Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 18/20] dlb: add dynamic " Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 19/20] dlb: add queue unmap " Mike Ximing Chen
2021-01-22 19:01 ` [PATCH v9 20/20] dlb: queue map/unmap workqueue Mike Ximing Chen
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