Commit e481fc0a authored by Sagi Grimberg's avatar Sagi Grimberg Committed by Christoph Hellwig
Browse files

nvme-auth: guarantee dhchap buffers under memory pressure 



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: default avatarSagi Grimberg <sagi@grimberg.me>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent b7d604ca

drivers/nvme/host/auth.c

+28 −2
Original line number Diff line number Diff line
@@ -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(struct nvme_dhchap_queue_context *chap) 
	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 work_struct *work) 
	 * 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 *ctrl) 
	}

}

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);

}

drivers/nvme/host/core.c

+6 −0
Original line number Diff line number Diff line
@@ -5347,8 +5347,13 @@ 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:
@@ -5369,6 +5374,7 @@ 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);

drivers/nvme/host/nvme.h

+9 −0
Original line number Diff line number Diff line
@@ -1018,6 +1018,8 @@ static inline bool nvme_ctrl_sgl_supported(struct nvme_ctrl *ctrl) 
}



#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);
@@ -1029,6 +1031,13 @@ static inline int nvme_auth_init_ctrl(struct nvme_ctrl *ctrl) 
{

	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)

{