From: Sagi Grimberg <sagi@grimberg.me>
Date: Tue, 15 Nov 2022 17:08:06 +0100
Subject: nvme-auth: guarantee dhchap buffers under memory pressure
Patch-mainline: v6.2-rc1
Git-commit: e481fc0a377798976d5c3044c7f10c86a8372b92
References: bsc#1202633
We want to guarantee that we have chap buffers when a controller
reconnects under memory pressure. Add a mempool specifically
for that.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Daniel Wagner <dwagner@suse.de>
---
drivers/nvme/host/auth.c | 30 ++++++++++++++++++++++++++++--
drivers/nvme/host/core.c | 6 ++++++
drivers/nvme/host/nvme.h | 9 +++++++++
3 files changed, 43 insertions(+), 2 deletions(-)
--- a/drivers/nvme/host/auth.c
+++ b/drivers/nvme/host/auth.c
@@ -14,6 +14,8 @@
#include <linux/nvme-auth.h>
#define CHAP_BUF_SIZE 4096
+static struct kmem_cache *nvme_chap_buf_cache;
+static mempool_t *nvme_chap_buf_pool;
struct nvme_dhchap_queue_context {
struct list_head entry;
@@ -675,7 +677,7 @@ static void nvme_auth_reset_dhchap(struc
chap->transaction = 0;
memset(chap->c1, 0, sizeof(chap->c1));
memset(chap->c2, 0, sizeof(chap->c2));
- kfree(chap->buf);
+ mempool_free(chap->buf, nvme_chap_buf_pool);
chap->buf = NULL;
}
@@ -701,7 +703,7 @@ static void nvme_queue_auth_work(struct
* Allocate a large enough buffer for the entire negotiation:
* 4k is enough to ffdhe8192.
*/
- chap->buf = kmalloc(CHAP_BUF_SIZE, GFP_KERNEL);
+ chap->buf = mempool_alloc(nvme_chap_buf_pool, GFP_KERNEL);
if (!chap->buf) {
chap->error = -ENOMEM;
return;
@@ -1029,3 +1031,27 @@ void nvme_auth_free(struct nvme_ctrl *ct
}
}
EXPORT_SYMBOL_GPL(nvme_auth_free);
+
+int __init nvme_init_auth(void)
+{
+ nvme_chap_buf_cache = kmem_cache_create("nvme-chap-buf-cache",
+ CHAP_BUF_SIZE, 0, SLAB_HWCACHE_ALIGN, NULL);
+ if (!nvme_chap_buf_cache)
+ return -ENOMEM;
+
+ nvme_chap_buf_pool = mempool_create(16, mempool_alloc_slab,
+ mempool_free_slab, nvme_chap_buf_cache);
+ if (!nvme_chap_buf_pool)
+ goto err_destroy_chap_buf_cache;
+
+ return 0;
+err_destroy_chap_buf_cache:
+ kmem_cache_destroy(nvme_chap_buf_cache);
+ return -ENOMEM;
+}
+
+void __exit nvme_exit_auth(void)
+{
+ mempool_destroy(nvme_chap_buf_pool);
+ kmem_cache_destroy(nvme_chap_buf_cache);
+}
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -5231,8 +5231,13 @@ static int __init nvme_core_init(void)
goto unregister_generic_ns;
}
+ result = nvme_init_auth();
+ if (result)
+ goto destroy_ns_chr;
return 0;
+destroy_ns_chr:
+ class_destroy(nvme_ns_chr_class);
unregister_generic_ns:
unregister_chrdev_region(nvme_ns_chr_devt, NVME_MINORS);
destroy_subsys_class:
@@ -5253,6 +5258,7 @@ static int __init nvme_core_init(void)
static void __exit nvme_core_exit(void)
{
+ nvme_exit_auth();
class_destroy(nvme_ns_chr_class);
class_destroy(nvme_subsys_class);
class_destroy(nvme_class);
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -1011,6 +1011,8 @@ static inline bool nvme_ctrl_sgl_support
}
#ifdef CONFIG_NVME_AUTH
+int __init nvme_init_auth(void);
+void __exit nvme_exit_auth(void);
int nvme_auth_init_ctrl(struct nvme_ctrl *ctrl);
void nvme_auth_stop(struct nvme_ctrl *ctrl);
int nvme_auth_negotiate(struct nvme_ctrl *ctrl, int qid);
@@ -1022,6 +1024,13 @@ static inline int nvme_auth_init_ctrl(st
{
return 0;
}
+static inline int __init nvme_init_auth(void)
+{
+ return 0;
+}
+static inline void __exit nvme_exit_auth(void)
+{
+}
static inline void nvme_auth_stop(struct nvme_ctrl *ctrl) {};
static inline int nvme_auth_negotiate(struct nvme_ctrl *ctrl, int qid)
{