From: Leon Romanovsky <leonro@xxxxxxxxxxxx>
Generate unique resource ID for SW and HW capable devices.
RES_VALID marker is introduced as a temporal measure till
all drivers are converted to use restrask IDs. After that,
it will be safe to remove RES_VISIBLE and expose all objects,
including internal ones.
Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx>
---
drivers/infiniband/core/nldev.c | 2 +-
drivers/infiniband/core/restrack.c | 132 +++++++++++++++++++++++------
include/rdma/restrack.h | 13 +++
3 files changed, 118 insertions(+), 29 deletions(-)
diff --git a/drivers/infiniband/core/nldev.c b/drivers/infiniband/core/nldev.c
index 01e20bbdd7db..b9756a5cdf4f 100644
--- a/drivers/infiniband/core/nldev.c
+++ b/drivers/infiniband/core/nldev.c
@@ -1083,7 +1083,7 @@ static int res_get_common_dumpit(struct sk_buff *skb,
xa = rdma_dev_to_xa(device, res_type);
rdma_rt_read_lock(device, res_type);
- xa_for_each(xa, res, id, ULONG_MAX, XA_PRESENT) {
+ xa_for_each(xa, res, id, ULONG_MAX, RES_VISIBLE) {
if (idx < start)
goto next;
diff --git a/drivers/infiniband/core/restrack.c b/drivers/infiniband/core/restrack.c
index 5a8857cab822..a67bf8e77876 100644
--- a/drivers/infiniband/core/restrack.c
+++ b/drivers/infiniband/core/restrack.c
@@ -21,6 +21,30 @@ struct rt_xa_limit {
u32 min;
u32 max;
};
+static int rt_xa_alloc_cyclic(struct xarray *xa, u32 *id, void *entry,
+ const struct rt_xa_limit *limit, u32 *next,
+ gfp_t gfp)
+{
+ int err;
+
+ if (*next < limit->max)
+ *id = *next;
+ else
+ *id = limit->min;
+
+ xa_lock(xa);
+ err = __xa_alloc(xa, id, limit->max, entry, gfp);
+
+ if (err && *next > limit->min) {
+ *id = limit->min;
+ err = __xa_alloc(xa, id, limit->max, entry, gfp);
+ }
+
+ if (!err)
+ *next = *id + 1;
+ xa_unlock(xa);
+ return err;
+}
/**
* struct rdma_restrack_root - main resource tracking management
@@ -40,6 +64,10 @@ struct rdma_restrack_root {
* @range: Allocation ID range between min and max
*/
struct rt_xa_limit range;
+ /**
+ * @next_id: Next ID to support cyclic allocation
+ */
+ u32 next_id;
};
/**
@@ -63,6 +91,15 @@ int rdma_restrack_init(struct ib_device *dev)
init_rwsem(&rt[i].rwsem);
xa_init_flags(&rt[i].xa, XA_FLAGS_ALLOC);
rt[i].range.max = U32_MAX;
+ /*
+ * This is supplementary part of xa_load() check in
+ * rdma_restrack_add(), and will be removed once all
+ * drivers converted. Those values are usable in SW
+ * allocation scheme only and will prevent assignment
+ * of 0 index.
+ */
+ rt[i].range.min = 1;
+ rt[i].next_id = 1;
}
return 0;
@@ -187,7 +224,7 @@ int rdma_restrack_count(struct ib_device *dev, enum rdma_restrack_type type,
u32 cnt = 0;
rdma_rt_read_lock(dev, type);
- xa_for_each(xa, e, index, ULONG_MAX, XA_PRESENT) {
+ xa_for_each(xa, e, index, ULONG_MAX, RES_VISIBLE) {
if (ns == &init_pid_ns ||
(!rdma_is_kernel_res(e) &&
ns == task_active_pid_ns(e->task)))
@@ -261,38 +298,57 @@ void rdma_restrack_set_task(struct rdma_restrack_entry *res,
}
EXPORT_SYMBOL(rdma_restrack_set_task);
-static unsigned long res_to_id(struct rdma_restrack_entry *res)
-{
- switch (res->type) {
- case RDMA_RESTRACK_PD:
- case RDMA_RESTRACK_MR:
- case RDMA_RESTRACK_CM_ID:
- case RDMA_RESTRACK_CTX:
- case RDMA_RESTRACK_CQ:
- case RDMA_RESTRACK_QP:
- return (unsigned long)res;
- default:
- WARN_ONCE(true, "Wrong resource tracking type %u\n", res->type);
- return 0;
- }
-}
-
-static void rdma_restrack_add(struct rdma_restrack_entry *res)
+/**
+ * rdma_restrack_add() - add new resoruce to DB and get ID in return
+ * @res: resoruce to add
+ *
+ * Return: 0 on success
+ */
+int rdma_restrack_add(struct rdma_restrack_entry *res)
{
struct ib_device *dev = res_to_dev(res);
struct xarray *xa = rdma_dev_to_xa(dev, res->type);
+ struct rdma_restrack_root *rt = dev->res;
int ret;
+ /*
+ * Once all drivers are converted, we can remove this check
+ * and remove call to rdma_restrack_add() from rdma_restrack_kadd()
+ * and rdma_restrack_uadd()
+ */
+ if (xa_load(xa, res->id))
+ return 0;
+
kref_init(&res->kref);
init_completion(&res->comp);
res->valid = true;
- ret = xa_insert(xa, res_to_id(res), res, GFP_KERNEL);
- WARN_ONCE(ret == -EEXIST, "Tried to add non-unique type %d entry\n",
- res->type);
+ if (rt[res->type].range.max) {
+ /* Not HW-capable device */
+ ret = rt_xa_alloc_cyclic(xa, &res->id, res,
+ &rt[res->type].range,
+ &rt[res->type].next_id, GFP_KERNEL);
+ } else {
+ ret = xa_insert(xa, res->id, res, GFP_KERNEL);
+ }
+
+ /*
+ * WARNs below indicates an error in driver code.
+ * The check of -EEXIST is never occuried and added here
+ * to allow simple removal of xa_load above.
+ */
+ WARN_ONCE(ret == -EEXIST, "Tried to add non-unique %s entry %u\n",
+ type2str(res->type), res->id);
+ WARN_ONCE(ret == -ENOSPC,
+ "There are no more free indexes for type %s entry %u\n",
+ type2str(res->type), res->id);
+
if (ret)
res->valid = false;
+
+ return ret;
}
+EXPORT_SYMBOL(rdma_restrack_add);
/**
* rdma_restrack_kadd() - add kernel object to the reource tracking database
@@ -300,10 +356,20 @@ static void rdma_restrack_add(struct rdma_restrack_entry *res)
*/
void rdma_restrack_kadd(struct rdma_restrack_entry *res)
{
+ struct ib_device *dev = res_to_dev(res);
+ struct xarray *xa = rdma_dev_to_xa(dev, res->type);
+
res->task = NULL;
set_kern_name(res);
res->user = false;
- rdma_restrack_add(res);
+ /*
+ * Temporaly, we are not intested in return value,
+ * once conversion will be finished, it will be checked by drivers.
+ */
+ if (rdma_restrack_add(res))
+ return;
+
+ xa_set_mark(xa, res->id, RES_VISIBLE);
}
EXPORT_SYMBOL(rdma_restrack_kadd);
@@ -313,6 +379,9 @@ EXPORT_SYMBOL(rdma_restrack_kadd);
*/
void rdma_restrack_uadd(struct rdma_restrack_entry *res)
{
+ struct ib_device *dev = res_to_dev(res);
+ struct xarray *xa = rdma_dev_to_xa(dev, res->type);
+
if (res->type != RDMA_RESTRACK_CM_ID)
res->task = NULL;
@@ -321,7 +390,14 @@ void rdma_restrack_uadd(struct rdma_restrack_entry *res)
res->kern_name = NULL;
res->user = true;
- rdma_restrack_add(res);
+ /*
+ * Temporaly, we are not intested in return value,
+ * once conversion will be finished, it will be checked by drivers.
+ */
+ if (rdma_restrack_add(res))
+ return;
+
+ xa_set_mark(xa, res->id, RES_VISIBLE);
}
EXPORT_SYMBOL(rdma_restrack_uadd);
@@ -347,7 +423,8 @@ rdma_restrack_get_byid(struct ib_device *dev,
struct rdma_restrack_entry *res;
res = xa_load(xa, id);
- if (!res || xa_is_err(res) || !rdma_restrack_get(res))
+ if (!res || !rdma_restrack_get(res) ||
+ !xa_get_mark(xa, res->id, RES_VISIBLE))
return ERR_PTR(-ENOENT);
return res;
}
@@ -371,7 +448,6 @@ void rdma_restrack_del(struct rdma_restrack_entry *res)
{
struct ib_device *dev = res_to_dev(res);
struct xarray *xa;
- unsigned long id;
if (!res->valid)
goto out;
@@ -393,8 +469,7 @@ void rdma_restrack_del(struct rdma_restrack_entry *res)
return;
xa = rdma_dev_to_xa(dev, res->type);
- id = res_to_id(res);
- if (!xa_load(xa, id))
+ if (!xa_load(xa, res->id))
goto out;
rdma_restrack_put(res);
@@ -402,7 +477,7 @@ void rdma_restrack_del(struct rdma_restrack_entry *res)
wait_for_completion(&res->comp);
down_write(&dev->res[res->type].rwsem);
- xa_erase(xa, id);
+ xa_erase(xa, res->id);
res->valid = false;
up_write(&dev->res[res->type].rwsem);
@@ -430,5 +505,6 @@ void rdma_rt_set_id_range(struct ib_device *dev, enum rdma_restrack_type type,
rt[type].range.max = max;
rt[type].range.min = reserved;
+ rt[type].next_id = reserved;
}
EXPORT_SYMBOL(rdma_rt_set_id_range);
diff --git a/include/rdma/restrack.h b/include/rdma/restrack.h
index 0706f51bb1f8..9d329098ddfc 100644
--- a/include/rdma/restrack.h
+++ b/include/rdma/restrack.h
@@ -93,6 +93,11 @@ struct rdma_restrack_entry {
* @user: user resource
*/
bool user;
+ /*
+ * @id: unique to specific type identifier, for HW-capable devices,
+ * drivers are supposed to update it, because it is used as an index.
+ */
+ u32 id;
};
int rdma_restrack_init(struct ib_device *dev);
@@ -104,6 +109,14 @@ int rdma_restrack_count(struct ib_device *dev,
void rdma_restrack_kadd(struct rdma_restrack_entry *res);
void rdma_restrack_uadd(struct rdma_restrack_entry *res);
+/**
+ * Addition of entry is performed in two steps approach:
+ * 1. Driver creates ID and allocates resource entry.
+ * 2. IB/core marks such entry as user/kernel and exports to nldev.c
+ */
+#define RES_VISIBLE XA_MARK_2
+int rdma_restrack_add(struct rdma_restrack_entry *res);
+
/**
* rdma_restrack_del() - delete object from the reource tracking database
* @res: resource entry
--
2.19.1
