From: Seth Jennings Subject: Re: [RFC PATCH v1 1/1] mm: zswap - Add crypto acomp/scomp framework support Date: Tue, 14 Feb 2017 10:20:40 -0600 Message-ID: References: <1487086821-5880-1-git-send-email-Mahipal.Challa@cavium.com> <1487086821-5880-2-git-send-email-Mahipal.Challa@cavium.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: herbert@gondor.apana.org.au, davem@davemloft.net, linux-crypto@vger.kernel.org, LKML , Linux-MM , pathreya@cavium.com, vnair@cavium.com, Mahipal Challa , Vishnu Nair To: Mahipal Challa Return-path: Received: from mail-oi0-f49.google.com ([209.85.218.49]:33428 "EHLO mail-oi0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754665AbdBNQUm (ORCPT ); Tue, 14 Feb 2017 11:20:42 -0500 Received: by mail-oi0-f49.google.com with SMTP id w204so72760532oiw.0 for ; Tue, 14 Feb 2017 08:20:42 -0800 (PST) In-Reply-To: <1487086821-5880-2-git-send-email-Mahipal.Challa@cavium.com> Sender: linux-crypto-owner@vger.kernel.org List-ID: On Tue, Feb 14, 2017 at 9:40 AM, Mahipal Challa wrote: > This adds the support for kernel's crypto new acomp/scomp framework > to zswap. > > Signed-off-by: Mahipal Challa > Signed-off-by: Vishnu Nair > --- > mm/zswap.c | 129 +++++++++++++++++++++++++++++++++++++++++++++++-------------- > 1 file changed, 99 insertions(+), 30 deletions(-) > > diff --git a/mm/zswap.c b/mm/zswap.c > index 067a0d6..d08631b 100644 > --- a/mm/zswap.c > +++ b/mm/zswap.c > @@ -33,6 +33,8 @@ > #include > #include > #include > +#include > +#include > #include > #include > > @@ -114,7 +116,8 @@ static int zswap_compressor_param_set(const char *, > > struct zswap_pool { > struct zpool *zpool; > - struct crypto_comp * __percpu *tfm; > + struct crypto_acomp * __percpu *acomp; > + struct acomp_req * __percpu *acomp_req; > struct kref kref; > struct list_head list; > struct work_struct work; > @@ -379,30 +382,49 @@ static int zswap_dstmem_dead(unsigned int cpu) > 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_comp *tfm; > + struct crypto_acomp *acomp; > + struct acomp_req *acomp_req; > > - if (WARN_ON(*per_cpu_ptr(pool->tfm, cpu))) > + if (WARN_ON(*per_cpu_ptr(pool->acomp, cpu))) > return 0; > + if (WARN_ON(*per_cpu_ptr(pool->acomp_req, cpu))) > + return 0; > + > + acomp = crypto_alloc_acomp(pool->tfm_name, 0, 0); > + if (IS_ERR_OR_NULL(acomp)) { > + pr_err("could not alloc crypto acomp %s : %ld\n", > + pool->tfm_name, PTR_ERR(acomp)); > + return -ENOMEM; > + } > + *per_cpu_ptr(pool->acomp, cpu) = acomp; > > - tfm = crypto_alloc_comp(pool->tfm_name, 0, 0); > - if (IS_ERR_OR_NULL(tfm)) { > - pr_err("could not alloc crypto comp %s : %ld\n", > - pool->tfm_name, PTR_ERR(tfm)); > + acomp_req = acomp_request_alloc(acomp); > + if (IS_ERR_OR_NULL(acomp_req)) { > + pr_err("could not alloc crypto acomp %s : %ld\n", > + pool->tfm_name, PTR_ERR(acomp)); > return -ENOMEM; > } > - *per_cpu_ptr(pool->tfm, cpu) = tfm; > + *per_cpu_ptr(pool->acomp_req, cpu) = acomp_req; > + > return 0; > } > > 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_comp *tfm; > + struct crypto_acomp *acomp; > + struct acomp_req *acomp_req; > + > + acomp_req = *per_cpu_ptr(pool->acomp_req, cpu); > + if (!IS_ERR_OR_NULL(acomp_req)) > + acomp_request_free(acomp_req); > + *per_cpu_ptr(pool->acomp_req, cpu) = NULL; > + > + acomp = *per_cpu_ptr(pool->acomp, cpu); > + if (!IS_ERR_OR_NULL(acomp)) > + crypto_free_acomp(acomp); > + *per_cpu_ptr(pool->acomp, cpu) = NULL; > > - tfm = *per_cpu_ptr(pool->tfm, cpu); > - if (!IS_ERR_OR_NULL(tfm)) > - crypto_free_comp(tfm); > - *per_cpu_ptr(pool->tfm, cpu) = NULL; > return 0; > } > > @@ -503,8 +525,14 @@ static struct zswap_pool *zswap_pool_create(char *type, char *compressor) > pr_debug("using %s zpool\n", zpool_get_type(pool->zpool)); > > strlcpy(pool->tfm_name, compressor, sizeof(pool->tfm_name)); > - pool->tfm = alloc_percpu(struct crypto_comp *); > - if (!pool->tfm) { > + pool->acomp = alloc_percpu(struct crypto_acomp *); > + if (!pool->acomp) { > + pr_err("percpu alloc failed\n"); > + goto error; > + } > + > + pool->acomp_req = alloc_percpu(struct acomp_req *); > + if (!pool->acomp_req) { > pr_err("percpu alloc failed\n"); > goto error; > } > @@ -526,7 +554,8 @@ static struct zswap_pool *zswap_pool_create(char *type, char *compressor) > return pool; > > error: > - free_percpu(pool->tfm); > + free_percpu(pool->acomp_req); > + free_percpu(pool->acomp); > if (pool->zpool) > zpool_destroy_pool(pool->zpool); > kfree(pool); > @@ -566,7 +595,8 @@ static void zswap_pool_destroy(struct zswap_pool *pool) > zswap_pool_debug("destroying", pool); > > cpuhp_state_remove_instance(CPUHP_MM_ZSWP_POOL_PREPARE, &pool->node); > - free_percpu(pool->tfm); > + free_percpu(pool->acomp_req); > + free_percpu(pool->acomp); > zpool_destroy_pool(pool->zpool); > kfree(pool); > } > @@ -763,7 +793,8 @@ static int zswap_writeback_entry(struct zpool *pool, unsigned long handle) > pgoff_t offset; > struct zswap_entry *entry; > struct page *page; > - struct crypto_comp *tfm; > + struct scatterlist input, output; > + struct acomp_req *req; > u8 *src, *dst; > unsigned int dlen; > int ret; > @@ -803,14 +834,23 @@ static int zswap_writeback_entry(struct zpool *pool, unsigned long handle) > > case ZSWAP_SWAPCACHE_NEW: /* page is locked */ > /* decompress */ > + req = *get_cpu_ptr(entry->pool->acomp_req); > dlen = PAGE_SIZE; > src = (u8 *)zpool_map_handle(entry->pool->zpool, entry->handle, > ZPOOL_MM_RO) + sizeof(struct zswap_header); > dst = kmap_atomic(page); > - tfm = *get_cpu_ptr(entry->pool->tfm); > - ret = crypto_comp_decompress(tfm, src, entry->length, > - dst, &dlen); > - put_cpu_ptr(entry->pool->tfm); > + > + sg_init_one(&input, src, entry->length); > + sg_init_one(&output, dst, dlen); > + acomp_request_set_params(req, &input, &output, entry->length, > + dlen); > + acomp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG, > + NULL, NULL); > + > + ret = crypto_acomp_decompress(req); I assume all of these crypto_acomp_[compress|decompress] calls are actually synchronous, not asynchronous as the name suggests. Otherwise, this would blow up quite spectacularly since all the resources we use in the call get derefed/unmapped below. Could an async algorithm be implement/used that would break this assumption? Seth > + > + dlen = req->dlen; > + put_cpu_ptr(entry->pool->acomp_req); > kunmap_atomic(dst); > zpool_unmap_handle(entry->pool->zpool, entry->handle); > BUG_ON(ret); > @@ -886,7 +926,8 @@ static int zswap_frontswap_store(unsigned type, pgoff_t offset, > { > struct zswap_tree *tree = zswap_trees[type]; > struct zswap_entry *entry, *dupentry; > - struct crypto_comp *tfm; > + struct scatterlist input, output; > + struct acomp_req *req; > int ret; > unsigned int dlen = PAGE_SIZE, len; > unsigned long handle; > @@ -925,12 +966,27 @@ static int zswap_frontswap_store(unsigned type, pgoff_t offset, > } > > /* compress */ > + req = *get_cpu_ptr(entry->pool->acomp_req); > + if (!req) { > + put_cpu_ptr(entry->pool->acomp_req); > + ret = -EINVAL; > + goto freepage; > + } > + > dst = get_cpu_var(zswap_dstmem); > - tfm = *get_cpu_ptr(entry->pool->tfm); > src = kmap_atomic(page); > - ret = crypto_comp_compress(tfm, src, PAGE_SIZE, dst, &dlen); > + > + sg_init_one(&input, src, PAGE_SIZE); > + /* zswap_dstmem is of size (PAGE_SIZE * 2). Reflect same in sg_list */ > + sg_init_one(&output, dst, PAGE_SIZE * 2); > + acomp_request_set_params(req, &input, &output, PAGE_SIZE, dlen); > + acomp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG, NULL, > + NULL); > + > + ret = crypto_acomp_compress(req); > kunmap_atomic(src); > - put_cpu_ptr(entry->pool->tfm); > + put_cpu_ptr(entry->pool->acomp_req); > + dlen = req->dlen; > if (ret) { > ret = -EINVAL; > goto put_dstmem; > @@ -998,7 +1054,8 @@ static int zswap_frontswap_load(unsigned type, pgoff_t offset, > { > struct zswap_tree *tree = zswap_trees[type]; > struct zswap_entry *entry; > - struct crypto_comp *tfm; > + struct scatterlist input, output; > + struct acomp_req *req; > u8 *src, *dst; > unsigned int dlen; > int ret; > @@ -1014,13 +1071,25 @@ static int zswap_frontswap_load(unsigned type, pgoff_t offset, > spin_unlock(&tree->lock); > > /* decompress */ > + req = *get_cpu_ptr(entry->pool->acomp_req); > + if (!req) { > + put_cpu_ptr(entry->pool->acomp_req); > + return -1; > + } > dlen = PAGE_SIZE; > src = (u8 *)zpool_map_handle(entry->pool->zpool, entry->handle, > ZPOOL_MM_RO) + sizeof(struct zswap_header); > dst = kmap_atomic(page); > - tfm = *get_cpu_ptr(entry->pool->tfm); > - ret = crypto_comp_decompress(tfm, src, entry->length, dst, &dlen); > - put_cpu_ptr(entry->pool->tfm); > + > + sg_init_one(&input, src, entry->length); > + sg_init_one(&output, dst, dlen); > + acomp_request_set_params(req, &input, &output, entry->length, dlen); > + acomp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG, NULL, > + NULL); > + > + ret = crypto_acomp_decompress(req); > + > + put_cpu_ptr(entry->pool->acomp_req); > kunmap_atomic(dst); > zpool_unmap_handle(entry->pool->zpool, entry->handle); > BUG_ON(ret); > -- > 1.8.3.1 >