[PATCH v10 20/25] mm: zswap: Move the CPU hotplug procedures under "pool functions".

[Kanchana P Sridhar <kanchana.p.sridhar@intel.com>]

This patch merely moves zswap_cpu_comp_prepare() and
zswap_cpu_comp_dead() to be in the "pool functions" section because
these functions are invoked upon pool creation/deletion.

Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com>
---
 mm/zswap.c | 188 ++++++++++++++++++++++++++---------------------------
 1 file changed, 94 insertions(+), 94 deletions(-)

diff --git a/mm/zswap.c b/mm/zswap.c
index 3c0fd8a137182..3538ecaed5e16 100644
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -248,6 +248,100 @@ static inline struct xarray *swap_zswap_tree(swp_entry_t swp)
 **********************************/
 static void __zswap_pool_empty(struct percpu_ref *ref);
 
+static int zswap_cpu_comp_prepare(unsigned int cpu, struct hlist_node *node)
+{
+	struct zswap_pool *pool = hlist_entry(node, struct zswap_pool, node);
+	struct crypto_acomp_ctx *acomp_ctx = per_cpu_ptr(pool->acomp_ctx, cpu);
+	struct crypto_acomp *acomp = NULL;
+	struct acomp_req *req = NULL;
+	u8 *buffer = NULL;
+	int ret;
+
+	buffer = kmalloc_node(PAGE_SIZE * 2, GFP_KERNEL, cpu_to_node(cpu));
+	if (!buffer) {
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	acomp = crypto_alloc_acomp_node(pool->tfm_name, 0, 0, cpu_to_node(cpu));
+	if (IS_ERR(acomp)) {
+		pr_err("could not alloc crypto acomp %s : %ld\n",
+				pool->tfm_name, PTR_ERR(acomp));
+		ret = PTR_ERR(acomp);
+		goto fail;
+	}
+
+	req = acomp_request_alloc(acomp);
+	if (!req) {
+		pr_err("could not alloc crypto acomp_request %s\n",
+		       pool->tfm_name);
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	/*
+	 * Only hold the mutex after completing allocations, otherwise we may
+	 * recurse into zswap through reclaim and attempt to hold the mutex
+	 * again resulting in a deadlock.
+	 */
+	mutex_lock(&acomp_ctx->mutex);
+	crypto_init_wait(&acomp_ctx->wait);
+
+	/*
+	 * if the backend of acomp is async zip, crypto_req_done() will wakeup
+	 * crypto_wait_req(); if the backend of acomp is scomp, the callback
+	 * won't be called, crypto_wait_req() will return without blocking.
+	 */
+	acomp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
+				   crypto_req_done, &acomp_ctx->wait);
+
+	acomp_ctx->buffer = buffer;
+	acomp_ctx->acomp = acomp;
+	acomp_ctx->is_sleepable = acomp_is_async(acomp);
+	acomp_ctx->req = req;
+	mutex_unlock(&acomp_ctx->mutex);
+	return 0;
+
+fail:
+	if (acomp)
+		crypto_free_acomp(acomp);
+	kfree(buffer);
+	return ret;
+}
+
+static int zswap_cpu_comp_dead(unsigned int cpu, struct hlist_node *node)
+{
+	struct zswap_pool *pool = hlist_entry(node, struct zswap_pool, node);
+	struct crypto_acomp_ctx *acomp_ctx = per_cpu_ptr(pool->acomp_ctx, cpu);
+	struct acomp_req *req;
+	struct crypto_acomp *acomp;
+	u8 *buffer;
+
+	if (IS_ERR_OR_NULL(acomp_ctx))
+		return 0;
+
+	mutex_lock(&acomp_ctx->mutex);
+	req = acomp_ctx->req;
+	acomp = acomp_ctx->acomp;
+	buffer = acomp_ctx->buffer;
+	acomp_ctx->req = NULL;
+	acomp_ctx->acomp = NULL;
+	acomp_ctx->buffer = NULL;
+	mutex_unlock(&acomp_ctx->mutex);
+
+	/*
+	 * Do the actual freeing after releasing the mutex to avoid subtle
+	 * locking dependencies causing deadlocks.
+	 */
+	if (!IS_ERR_OR_NULL(req))
+		acomp_request_free(req);
+	if (!IS_ERR_OR_NULL(acomp))
+		crypto_free_acomp(acomp);
+	kfree(buffer);
+
+	return 0;
+}
+
 static struct zswap_pool *zswap_pool_create(char *type, char *compressor)
 {
 	struct zswap_pool *pool;
@@ -818,100 +912,6 @@ static void zswap_entry_free(struct zswap_entry *entry)
 /*********************************
 * compressed storage functions
 **********************************/
-static int zswap_cpu_comp_prepare(unsigned int cpu, struct hlist_node *node)
-{
-	struct zswap_pool *pool = hlist_entry(node, struct zswap_pool, node);
-	struct crypto_acomp_ctx *acomp_ctx = per_cpu_ptr(pool->acomp_ctx, cpu);
-	struct crypto_acomp *acomp = NULL;
-	struct acomp_req *req = NULL;
-	u8 *buffer = NULL;
-	int ret;
-
-	buffer = kmalloc_node(PAGE_SIZE * 2, GFP_KERNEL, cpu_to_node(cpu));
-	if (!buffer) {
-		ret = -ENOMEM;
-		goto fail;
-	}
-
-	acomp = crypto_alloc_acomp_node(pool->tfm_name, 0, 0, cpu_to_node(cpu));
-	if (IS_ERR(acomp)) {
-		pr_err("could not alloc crypto acomp %s : %ld\n",
-				pool->tfm_name, PTR_ERR(acomp));
-		ret = PTR_ERR(acomp);
-		goto fail;
-	}
-
-	req = acomp_request_alloc(acomp);
-	if (!req) {
-		pr_err("could not alloc crypto acomp_request %s\n",
-		       pool->tfm_name);
-		ret = -ENOMEM;
-		goto fail;
-	}
-
-	/*
-	 * Only hold the mutex after completing allocations, otherwise we may
-	 * recurse into zswap through reclaim and attempt to hold the mutex
-	 * again resulting in a deadlock.
-	 */
-	mutex_lock(&acomp_ctx->mutex);
-	crypto_init_wait(&acomp_ctx->wait);
-
-	/*
-	 * if the backend of acomp is async zip, crypto_req_done() will wakeup
-	 * crypto_wait_req(); if the backend of acomp is scomp, the callback
-	 * won't be called, crypto_wait_req() will return without blocking.
-	 */
-	acomp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG,
-				   crypto_req_done, &acomp_ctx->wait);
-
-	acomp_ctx->buffer = buffer;
-	acomp_ctx->acomp = acomp;
-	acomp_ctx->is_sleepable = acomp_is_async(acomp);
-	acomp_ctx->req = req;
-	mutex_unlock(&acomp_ctx->mutex);
-	return 0;
-
-fail:
-	if (acomp)
-		crypto_free_acomp(acomp);
-	kfree(buffer);
-	return ret;
-}
-
-static int zswap_cpu_comp_dead(unsigned int cpu, struct hlist_node *node)
-{
-	struct zswap_pool *pool = hlist_entry(node, struct zswap_pool, node);
-	struct crypto_acomp_ctx *acomp_ctx = per_cpu_ptr(pool->acomp_ctx, cpu);
-	struct acomp_req *req;
-	struct crypto_acomp *acomp;
-	u8 *buffer;
-
-	if (IS_ERR_OR_NULL(acomp_ctx))
-		return 0;
-
-	mutex_lock(&acomp_ctx->mutex);
-	req = acomp_ctx->req;
-	acomp = acomp_ctx->acomp;
-	buffer = acomp_ctx->buffer;
-	acomp_ctx->req = NULL;
-	acomp_ctx->acomp = NULL;
-	acomp_ctx->buffer = NULL;
-	mutex_unlock(&acomp_ctx->mutex);
-
-	/*
-	 * Do the actual freeing after releasing the mutex to avoid subtle
-	 * locking dependencies causing deadlocks.
-	 */
-	if (!IS_ERR_OR_NULL(req))
-		acomp_request_free(req);
-	if (!IS_ERR_OR_NULL(acomp))
-		crypto_free_acomp(acomp);
-	kfree(buffer);
-
-	return 0;
-}
-
 static struct crypto_acomp_ctx *acomp_ctx_get_cpu_lock(struct zswap_pool *pool)
 {
 	struct crypto_acomp_ctx *acomp_ctx;
-- 
2.27.0