[PATCH v4 2/5] crypto: scompress - use sgl_alloc() and sgl_free()

[Bart Van Assche]

Use the sgl_alloc() and sgl_free() functions instead of open coding
these functions.

Signed-off-by: Bart Van Assche <bart.vanass...@wdc.com>
Acked-by: Ard Biesheuvel <ard.biesheu...@linaro.org>
Cc: Herbert Xu <herb...@gondor.apana.org.au>
---
 crypto/Kconfig     |  1 +
 crypto/scompress.c | 51 ++-------------------------------------------------
 2 files changed, 3 insertions(+), 49 deletions(-)

diff --git a/crypto/Kconfig b/crypto/Kconfig
index f7911963bb79..20360e040425 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -106,6 +106,7 @@ config CRYPTO_KPP
 config CRYPTO_ACOMP2
        tristate
        select CRYPTO_ALGAPI2
+       select SGL_ALLOC
 
 config CRYPTO_ACOMP
        tristate
diff --git a/crypto/scompress.c b/crypto/scompress.c
index 2075e2c4e7df..968bbcf65c94 100644
--- a/crypto/scompress.c
+++ b/crypto/scompress.c
@@ -140,53 +140,6 @@ static int crypto_scomp_init_tfm(struct crypto_tfm *tfm)
        return ret;
 }
 
-static void crypto_scomp_sg_free(struct scatterlist *sgl)
-{
-       int i, n;
-       struct page *page;
-
-       if (!sgl)
-               return;
-
-       n = sg_nents(sgl);
-       for_each_sg(sgl, sgl, n, i) {
-               page = sg_page(sgl);
-               if (page)
-                       __free_page(page);
-       }
-
-       kfree(sgl);
-}
-
-static struct scatterlist *crypto_scomp_sg_alloc(size_t size, gfp_t gfp)
-{
-       struct scatterlist *sgl;
-       struct page *page;
-       int i, n;
-
-       n = ((size - 1) >> PAGE_SHIFT) + 1;
-
-       sgl = kmalloc_array(n, sizeof(struct scatterlist), gfp);
-       if (!sgl)
-               return NULL;
-
-       sg_init_table(sgl, n);
-
-       for (i = 0; i < n; i++) {
-               page = alloc_page(gfp);
-               if (!page)
-                       goto err;
-               sg_set_page(sgl + i, page, PAGE_SIZE, 0);
-       }
-
-       return sgl;
-
-err:
-       sg_mark_end(sgl + i);
-       crypto_scomp_sg_free(sgl);
-       return NULL;
-}
-
 static int scomp_acomp_comp_decomp(struct acomp_req *req, int dir)
 {
        struct crypto_acomp *tfm = crypto_acomp_reqtfm(req);
@@ -220,7 +173,7 @@ static int scomp_acomp_comp_decomp(struct acomp_req *req, 
int dir)
                                              scratch_dst, &req->dlen, *ctx);
        if (!ret) {
                if (!req->dst) {
-                       req->dst = crypto_scomp_sg_alloc(req->dlen, GFP_ATOMIC);
+                       req->dst = sgl_alloc(req->dlen, GFP_ATOMIC, NULL);
                        if (!req->dst)
                                goto out;
                }
@@ -274,7 +227,7 @@ int crypto_init_scomp_ops_async(struct crypto_tfm *tfm)
 
        crt->compress = scomp_acomp_compress;
        crt->decompress = scomp_acomp_decompress;
-       crt->dst_free = crypto_scomp_sg_free;
+       crt->dst_free = sgl_free;
        crt->reqsize = sizeof(void *);
 
        return 0;
-- 
2.15.1