RDMA/hns: Use refcount_t APIs for HEM

[ Upstream commit 82eb481da64586ccd287b2b2c5a086202c65e7eb ]

refcount_t is better than integer for reference counting, it will WARN on
overflow/underflow and avoid use-after-free risks.

Link: https://lore.kernel.org/r/1621589395-2435-5-git-send-email-liweihang@huawei.com
Signed-off-by: Weihang Li <liweihang@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Stable-dep-of: cf5b608fb0e3 ("RDMA/hns: Fix hns_roce_table_get return value")
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Weihang Li 2021-05-21 17:29:54 +08:00 committed by Greg Kroah-Hartman
parent de1049dd18
commit aa495b927f
2 changed files with 17 additions and 19 deletions

View File

@ -260,7 +260,6 @@ static struct hns_roce_hem *hns_roce_alloc_hem(struct hns_roce_dev *hr_dev,
if (!hem) if (!hem)
return NULL; return NULL;
hem->refcount = 0;
INIT_LIST_HEAD(&hem->chunk_list); INIT_LIST_HEAD(&hem->chunk_list);
order = get_order(hem_alloc_size); order = get_order(hem_alloc_size);
@ -607,7 +606,7 @@ static int hns_roce_table_mhop_get(struct hns_roce_dev *hr_dev,
mutex_lock(&table->mutex); mutex_lock(&table->mutex);
if (table->hem[index.buf]) { if (table->hem[index.buf]) {
++table->hem[index.buf]->refcount; refcount_inc(&table->hem[index.buf]->refcount);
goto out; goto out;
} }
@ -626,7 +625,7 @@ static int hns_roce_table_mhop_get(struct hns_roce_dev *hr_dev,
} }
} }
++table->hem[index.buf]->refcount; refcount_set(&table->hem[index.buf]->refcount, 1);
goto out; goto out;
err_alloc: err_alloc:
@ -652,7 +651,7 @@ int hns_roce_table_get(struct hns_roce_dev *hr_dev,
mutex_lock(&table->mutex); mutex_lock(&table->mutex);
if (table->hem[i]) { if (table->hem[i]) {
++table->hem[i]->refcount; refcount_inc(&table->hem[i]->refcount);
goto out; goto out;
} }
@ -675,7 +674,7 @@ int hns_roce_table_get(struct hns_roce_dev *hr_dev,
goto out; goto out;
} }
++table->hem[i]->refcount; refcount_set(&table->hem[i]->refcount, 1);
out: out:
mutex_unlock(&table->mutex); mutex_unlock(&table->mutex);
return ret; return ret;
@ -742,11 +741,11 @@ static void hns_roce_table_mhop_put(struct hns_roce_dev *hr_dev,
return; return;
} }
mutex_lock(&table->mutex); if (!check_refcount)
if (check_refcount && (--table->hem[index.buf]->refcount > 0)) { mutex_lock(&table->mutex);
mutex_unlock(&table->mutex); else if (!refcount_dec_and_mutex_lock(&table->hem[index.buf]->refcount,
&table->mutex))
return; return;
}
clear_mhop_hem(hr_dev, table, obj, &mhop, &index); clear_mhop_hem(hr_dev, table, obj, &mhop, &index);
free_mhop_hem(hr_dev, table, &mhop, &index); free_mhop_hem(hr_dev, table, &mhop, &index);
@ -768,16 +767,15 @@ void hns_roce_table_put(struct hns_roce_dev *hr_dev,
i = (obj & (table->num_obj - 1)) / i = (obj & (table->num_obj - 1)) /
(table->table_chunk_size / table->obj_size); (table->table_chunk_size / table->obj_size);
mutex_lock(&table->mutex); if (!refcount_dec_and_mutex_lock(&table->hem[i]->refcount,
&table->mutex))
return;
if (--table->hem[i]->refcount == 0) { if (hr_dev->hw->clear_hem(hr_dev, table, obj, 0))
/* Clear HEM base address */ dev_warn(dev, "failed to clear HEM base address.\n");
if (hr_dev->hw->clear_hem(hr_dev, table, obj, 0))
dev_warn(dev, "Clear HEM base address failed.\n");
hns_roce_free_hem(hr_dev, table->hem[i]); hns_roce_free_hem(hr_dev, table->hem[i]);
table->hem[i] = NULL; table->hem[i] = NULL;
}
mutex_unlock(&table->mutex); mutex_unlock(&table->mutex);
} }

View File

@ -87,8 +87,8 @@ struct hns_roce_hem_chunk {
}; };
struct hns_roce_hem { struct hns_roce_hem {
struct list_head chunk_list; struct list_head chunk_list;
int refcount; refcount_t refcount;
}; };
struct hns_roce_hem_iter { struct hns_roce_hem_iter {