RDMA/hns: Fix different dgids mapping to the same dip_idx

DIP algorithm requires a one-to-one mapping between dgid and dip_idx.
Currently a queue 'spare_idx' is used to store QPN of QPs that use
DIP algorithm. For a new dgid, use a QPN from spare_idx as dip_idx.
This method lacks a mechanism for deduplicating QPN, which may result
in different dgids sharing the same dip_idx and break the one-to-one
mapping requirement.

This patch replaces spare_idx with xarray and introduces a refcnt of
a dip_idx to indicate the number of QPs that using this dip_idx.

The state machine for dip_idx management is implemented as:

* The entry at an index in xarray is empty -- This indicates that the
  corresponding dip_idx hasn't been created.

* The entry at an index in xarray is not empty but with 0 refcnt --
  This indicates that the corresponding dip_idx has been created but
  not used as dip_idx yet.

* The entry at an index in xarray is not empty and with non-0 refcnt --
  This indicates that the corresponding dip_idx is being used by refcnt
  number of DIP QPs.

Fixes: eb653eda1e91 ("RDMA/hns: Bugfix for incorrect association between dip_idx and dgid")
Fixes: f91696f2f053 ("RDMA/hns: Support congestion control type selection according to the FW")
Signed-off-by: Feng Fang <fangfeng4@huawei.com>
Signed-off-by: Junxian Huang <huangjunxian6@hisilicon.com>
Link: https://patch.msgid.link/20241112055553.3681129-1-huangjunxian6@hisilicon.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

diff --git a/drivers/infiniband/hw/hns/hns_roce_device.h b/drivers/infiniband/hw/hns/hns_roce_device.h
index 9b51d5a..560a1d9 100644 (file)
--- a/drivers/infiniband/hw/hns/hns_roce_device.h
+++ b/drivers/infiniband/hw/hns/hns_roce_device.h
@@ -489,12 +489,6 @@ struct hns_roce_bank {
        u32 next; /* Next ID to allocate. */
 };
 
-struct hns_roce_idx_table {
-       u32 *spare_idx;
-       u32 head;
-       u32 tail;
-};
-
 struct hns_roce_qp_table {
        struct hns_roce_hem_table       qp_table;
        struct hns_roce_hem_table       irrl_table;
@@ -503,7 +497,7 @@ struct hns_roce_qp_table {
        struct mutex                    scc_mutex;
        struct hns_roce_bank bank[HNS_ROCE_QP_BANK_NUM];
        struct mutex bank_mutex;
-       struct hns_roce_idx_table       idx_table;
+       struct xarray                   dip_xa;
 };
 
 struct hns_roce_cq_table {
@@ -658,6 +652,7 @@ struct hns_roce_qp {
        u8                      tc_mode;
        u8                      priority;
        spinlock_t flush_lock;
+       struct hns_roce_dip *dip;
 };
 
 struct hns_roce_ib_iboe {
@@ -984,8 +979,6 @@ struct hns_roce_dev {
        enum hns_roce_device_state state;
        struct list_head        qp_list; /* list of all qps on this dev */
        spinlock_t              qp_list_lock; /* protect qp_list */
-       struct list_head        dip_list; /* list of all dest ips on this dev */
-       spinlock_t              dip_list_lock; /* protect dip_list */
 
        struct list_head        pgdir_list;
        struct mutex            pgdir_mutex;

diff --git a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
index 707e96c..697b17c 100644 (file)
--- a/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
+++ b/drivers/infiniband/hw/hns/hns_roce_hw_v2.c
@@ -2553,20 +2553,19 @@ static void hns_roce_free_link_table(struct hns_roce_dev *hr_dev)
        free_link_table_buf(hr_dev, &priv->ext_llm);
 }
 
-static void free_dip_list(struct hns_roce_dev *hr_dev)
+static void free_dip_entry(struct hns_roce_dev *hr_dev)
 {
        struct hns_roce_dip *hr_dip;
-       struct hns_roce_dip *tmp;
-       unsigned long flags;
+       unsigned long idx;
 
-       spin_lock_irqsave(&hr_dev->dip_list_lock, flags);
+       xa_lock(&hr_dev->qp_table.dip_xa);
 
-       list_for_each_entry_safe(hr_dip, tmp, &hr_dev->dip_list, node) {
-               list_del(&hr_dip->node);
+       xa_for_each(&hr_dev->qp_table.dip_xa, idx, hr_dip) {
+               __xa_erase(&hr_dev->qp_table.dip_xa, hr_dip->dip_idx);
                kfree(hr_dip);
        }
 
-       spin_unlock_irqrestore(&hr_dev->dip_list_lock, flags);
+       xa_unlock(&hr_dev->qp_table.dip_xa);
 }
 
 static struct ib_pd *free_mr_init_pd(struct hns_roce_dev *hr_dev)
@@ -2974,7 +2973,7 @@ static void hns_roce_v2_exit(struct hns_roce_dev *hr_dev)
                hns_roce_free_link_table(hr_dev);
 
        if (hr_dev->pci_dev->revision == PCI_REVISION_ID_HIP09)
-               free_dip_list(hr_dev);
+               free_dip_entry(hr_dev);
 }
 
 static int hns_roce_mbox_post(struct hns_roce_dev *hr_dev,
@@ -4694,26 +4693,49 @@ static int modify_qp_rtr_to_rts(struct ib_qp *ibqp, int attr_mask,
        return 0;
 }
 
+static int alloc_dip_entry(struct xarray *dip_xa, u32 qpn)
+{
+       struct hns_roce_dip *hr_dip;
+       int ret;
+
+       hr_dip = xa_load(dip_xa, qpn);
+       if (hr_dip)
+               return 0;
+
+       hr_dip = kzalloc(sizeof(*hr_dip), GFP_KERNEL);
+       if (!hr_dip)
+               return -ENOMEM;
+
+       ret = xa_err(xa_store(dip_xa, qpn, hr_dip, GFP_KERNEL));
+       if (ret)
+               kfree(hr_dip);
+
+       return ret;
+}
+
 static int get_dip_ctx_idx(struct ib_qp *ibqp, const struct ib_qp_attr *attr,
                           u32 *dip_idx)
 {
        const struct ib_global_route *grh = rdma_ah_read_grh(&attr->ah_attr);
        struct hns_roce_dev *hr_dev = to_hr_dev(ibqp->device);
-       u32 *spare_idx = hr_dev->qp_table.idx_table.spare_idx;
-       u32 *head =  &hr_dev->qp_table.idx_table.head;
-       u32 *tail =  &hr_dev->qp_table.idx_table.tail;
+       struct xarray *dip_xa = &hr_dev->qp_table.dip_xa;
+       struct hns_roce_qp *hr_qp = to_hr_qp(ibqp);
        struct hns_roce_dip *hr_dip;
-       unsigned long flags;
+       unsigned long idx;
        int ret = 0;
 
-       spin_lock_irqsave(&hr_dev->dip_list_lock, flags);
+       ret = alloc_dip_entry(dip_xa, ibqp->qp_num);
+       if (ret)
+               return ret;
 
-       spare_idx[*tail] = ibqp->qp_num;
-       *tail = (*tail == hr_dev->caps.num_qps - 1) ? 0 : (*tail + 1);
+       xa_lock(dip_xa);
 
-       list_for_each_entry(hr_dip, &hr_dev->dip_list, node) {
-               if (!memcmp(grh->dgid.raw, hr_dip->dgid, GID_LEN_V2)) {
+       xa_for_each(dip_xa, idx, hr_dip) {
+               if (hr_dip->qp_cnt &&
+                   !memcmp(grh->dgid.raw, hr_dip->dgid, GID_LEN_V2)) {
                        *dip_idx = hr_dip->dip_idx;
+                       hr_dip->qp_cnt++;
+                       hr_qp->dip = hr_dip;
                        goto out;
                }
        }
@@ -4721,19 +4743,24 @@ static int get_dip_ctx_idx(struct ib_qp *ibqp, const struct ib_qp_attr *attr,
        /* If no dgid is found, a new dip and a mapping between dgid and
         * dip_idx will be created.
         */
-       hr_dip = kzalloc(sizeof(*hr_dip), GFP_ATOMIC);
-       if (!hr_dip) {
-               ret = -ENOMEM;
-               goto out;
+       xa_for_each(dip_xa, idx, hr_dip) {
+               if (hr_dip->qp_cnt)
+                       continue;
+
+               *dip_idx = idx;
+               memcpy(hr_dip->dgid, grh->dgid.raw, sizeof(grh->dgid.raw));
+               hr_dip->dip_idx = idx;
+               hr_dip->qp_cnt++;
+               hr_qp->dip = hr_dip;
+               break;
        }
 
-       memcpy(hr_dip->dgid, grh->dgid.raw, sizeof(grh->dgid.raw));
-       hr_dip->dip_idx = *dip_idx = spare_idx[*head];
-       *head = (*head == hr_dev->caps.num_qps - 1) ? 0 : (*head + 1);
-       list_add_tail(&hr_dip->node, &hr_dev->dip_list);
+       /* This should never happen. */
+       if (WARN_ON_ONCE(!hr_qp->dip))
+               ret = -ENOSPC;
 
 out:
-       spin_unlock_irqrestore(&hr_dev->dip_list_lock, flags);
+       xa_unlock(dip_xa);
        return ret;
 }
 
@@ -5587,6 +5614,20 @@ static int hns_roce_v2_destroy_qp_common(struct hns_roce_dev *hr_dev,
        return ret;
 }
 
+static void put_dip_ctx_idx(struct hns_roce_dev *hr_dev,
+                           struct hns_roce_qp *hr_qp)
+{
+       struct hns_roce_dip *hr_dip = hr_qp->dip;
+
+       xa_lock(&hr_dev->qp_table.dip_xa);
+
+       hr_dip->qp_cnt--;
+       if (!hr_dip->qp_cnt)
+               memset(hr_dip->dgid, 0, GID_LEN_V2);
+
+       xa_unlock(&hr_dev->qp_table.dip_xa);
+}
+
 int hns_roce_v2_destroy_qp(struct ib_qp *ibqp, struct ib_udata *udata)
 {
        struct hns_roce_dev *hr_dev = to_hr_dev(ibqp->device);
@@ -5600,6 +5641,9 @@ int hns_roce_v2_destroy_qp(struct ib_qp *ibqp, struct ib_udata *udata)
        spin_unlock_irqrestore(&hr_qp->flush_lock, flags);
        flush_work(&hr_qp->flush_work.work);
 
+       if (hr_qp->cong_type == CONG_TYPE_DIP)
+               put_dip_ctx_idx(hr_dev, hr_qp);
+
        ret = hns_roce_v2_destroy_qp_common(hr_dev, hr_qp, udata);
        if (ret)
                ibdev_err_ratelimited(&hr_dev->ib_dev,

diff --git a/drivers/infiniband/hw/hns/hns_roce_hw_v2.h b/drivers/infiniband/hw/hns/hns_roce_hw_v2.h
index dedb185..cbdbc9e 100644 (file)
--- a/drivers/infiniband/hw/hns/hns_roce_hw_v2.h
+++ b/drivers/infiniband/hw/hns/hns_roce_hw_v2.h
@@ -1348,7 +1348,7 @@ struct hns_roce_v2_priv {
 struct hns_roce_dip {
        u8 dgid[GID_LEN_V2];
        u32 dip_idx;
-       struct list_head node; /* all dips are on a list */
+       u32 qp_cnt;
 };
 
 struct fmea_ram_ecc {

diff --git a/drivers/infiniband/hw/hns/hns_roce_main.c b/drivers/infiniband/hw/hns/hns_roce_main.c
index 49315f3..ae24c81 100644 (file)
--- a/drivers/infiniband/hw/hns/hns_roce_main.c
+++ b/drivers/infiniband/hw/hns/hns_roce_main.c
@@ -1135,8 +1135,6 @@ int hns_roce_init(struct hns_roce_dev *hr_dev)
 
        INIT_LIST_HEAD(&hr_dev->qp_list);
        spin_lock_init(&hr_dev->qp_list_lock);
-       INIT_LIST_HEAD(&hr_dev->dip_list);
-       spin_lock_init(&hr_dev->dip_list_lock);
 
        ret = hns_roce_register_device(hr_dev);
        if (ret)

diff --git a/drivers/infiniband/hw/hns/hns_roce_qp.c b/drivers/infiniband/hw/hns/hns_roce_qp.c
index 2ad03ec..9e2e76c 100644 (file)
--- a/drivers/infiniband/hw/hns/hns_roce_qp.c
+++ b/drivers/infiniband/hw/hns/hns_roce_qp.c
@@ -1573,14 +1573,10 @@ int hns_roce_init_qp_table(struct hns_roce_dev *hr_dev)
        unsigned int reserved_from_bot;
        unsigned int i;
 
-       qp_table->idx_table.spare_idx = kcalloc(hr_dev->caps.num_qps,
-                                       sizeof(u32), GFP_KERNEL);
-       if (!qp_table->idx_table.spare_idx)
-               return -ENOMEM;
-
        mutex_init(&qp_table->scc_mutex);
        mutex_init(&qp_table->bank_mutex);
        xa_init(&hr_dev->qp_table_xa);
+       xa_init(&qp_table->dip_xa);
 
        reserved_from_bot = hr_dev->caps.reserved_qps;
 
@@ -1605,7 +1601,7 @@ void hns_roce_cleanup_qp_table(struct hns_roce_dev *hr_dev)
 
        for (i = 0; i < HNS_ROCE_QP_BANK_NUM; i++)
                ida_destroy(&hr_dev->qp_table.bank[i].ida);
+       xa_destroy(&hr_dev->qp_table.dip_xa);
        mutex_destroy(&hr_dev->qp_table.bank_mutex);
        mutex_destroy(&hr_dev->qp_table.scc_mutex);
-       kfree(hr_dev->qp_table.idx_table.spare_idx);
 }