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)
return NULL;
hem->refcount = 0;
INIT_LIST_HEAD(&hem->chunk_list);
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);
if (table->hem[index.buf]) {
++table->hem[index.buf]->refcount;
refcount_inc(&table->hem[index.buf]->refcount);
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;
err_alloc:
@ -652,7 +651,7 @@ int hns_roce_table_get(struct hns_roce_dev *hr_dev,
mutex_lock(&table->mutex);
if (table->hem[i]) {
++table->hem[i]->refcount;
refcount_inc(&table->hem[i]->refcount);
goto out;
}
@ -675,7 +674,7 @@ int hns_roce_table_get(struct hns_roce_dev *hr_dev,
goto out;
}
++table->hem[i]->refcount;
refcount_set(&table->hem[i]->refcount, 1);
out:
mutex_unlock(&table->mutex);
return ret;
@ -742,11 +741,11 @@ static void hns_roce_table_mhop_put(struct hns_roce_dev *hr_dev,
return;
}
mutex_lock(&table->mutex);
if (check_refcount && (--table->hem[index.buf]->refcount > 0)) {
mutex_unlock(&table->mutex);
if (!check_refcount)
mutex_lock(&table->mutex);
else if (!refcount_dec_and_mutex_lock(&table->hem[index.buf]->refcount,
&table->mutex))
return;
}
clear_mhop_hem(hr_dev, table, obj, &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)) /
(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) {
/* Clear HEM base address */
if (hr_dev->hw->clear_hem(hr_dev, table, obj, 0))
dev_warn(dev, "Clear HEM base address failed.\n");
if (hr_dev->hw->clear_hem(hr_dev, table, obj, 0))
dev_warn(dev, "failed to clear HEM base address.\n");
hns_roce_free_hem(hr_dev, table->hem[i]);
table->hem[i] = NULL;
}
hns_roce_free_hem(hr_dev, table->hem[i]);
table->hem[i] = NULL;
mutex_unlock(&table->mutex);
}

View File

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