crypto: scomp - Remove support for some non-trivial SG lists

As the only user of acomp/scomp uses a trivial single-page SG
list, remove support for everything else in preprataion for the
addition of virtual address support.

However, keep support for non-trivial source SG lists as that
user is currently jumping through hoops in order to linearise
the source data.

Limit the source SG linearisation buffer to a single page as
that user never goes over that.  The only other potential user
is also unlikely to exceed that (IPComp) and it can easily do
its own linearisation if necessary.

Also keep the destination SG linearisation for IPComp.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/crypto/acompress.c b/crypto/acompress.c
index 45444e99a9dbcd767026ef5b075b9d3c6f51c539..194a4b36f97fde7454382e49dcd4f4d64dbc000a 100644 (file)
--- a/crypto/acompress.c
+++ b/crypto/acompress.c
@@ -73,7 +73,6 @@ static int crypto_acomp_init_tfm(struct crypto_tfm *tfm)
 
        acomp->compress = alg->compress;
        acomp->decompress = alg->decompress;
-       acomp->dst_free = alg->dst_free;
        acomp->reqsize = alg->reqsize;
 
        if (alg->exit)

diff --git a/crypto/scompress.c b/crypto/scompress.c
index a2ce481a10bb26990fbabd081786931e4c516482..4441c40f541f45138e9776c8b8b4eccc083a48d9 100644 (file)
--- a/crypto/scompress.c
+++ b/crypto/scompress.c
@@ -12,8 +12,10 @@
 #include <crypto/scatterwalk.h>
 #include <linux/cryptouser.h>
 #include <linux/err.h>
+#include <linux/highmem.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/overflow.h>
 #include <linux/scatterlist.h>
 #include <linux/seq_file.h>
 #include <linux/slab.h>
@@ -23,9 +25,14 @@
 
 #include "compress.h"
 
+#define SCOMP_SCRATCH_SIZE 65400
+
 struct scomp_scratch {
        spinlock_t      lock;
-       void            *src;
+       union {
+               void    *src;
+               unsigned long saddr;
+       };
        void            *dst;
 };
 
@@ -66,7 +73,7 @@ static void crypto_scomp_free_scratches(void)
        for_each_possible_cpu(i) {
                scratch = per_cpu_ptr(&scomp_scratch, i);
 
-               vfree(scratch->src);
+               free_page(scratch->saddr);
                vfree(scratch->dst);
                scratch->src = NULL;
                scratch->dst = NULL;
@@ -79,14 +86,15 @@ static int crypto_scomp_alloc_scratches(void)
        int i;
 
        for_each_possible_cpu(i) {
+               struct page *page;
                void *mem;
 
                scratch = per_cpu_ptr(&scomp_scratch, i);
 
-               mem = vmalloc_node(SCOMP_SCRATCH_SIZE, cpu_to_node(i));
-               if (!mem)
+               page = alloc_pages_node(cpu_to_node(i), GFP_KERNEL, 0);
+               if (!page)
                        goto error;
-               scratch->src = mem;
+               scratch->src = page_address(page);
                mem = vmalloc_node(SCOMP_SCRATCH_SIZE, cpu_to_node(i));
                if (!mem)
                        goto error;
@@ -161,76 +169,88 @@ unlock:
 
 static int scomp_acomp_comp_decomp(struct acomp_req *req, int dir)
 {
+       struct scomp_scratch *scratch = raw_cpu_ptr(&scomp_scratch);
        struct crypto_acomp *tfm = crypto_acomp_reqtfm(req);
-       void **tfm_ctx = acomp_tfm_ctx(tfm);
+       struct crypto_scomp **tfm_ctx = acomp_tfm_ctx(tfm);
        struct crypto_scomp *scomp = *tfm_ctx;
        struct crypto_acomp_stream *stream;
-       struct scomp_scratch *scratch;
+       unsigned int slen = req->slen;
+       unsigned int dlen = req->dlen;
+       struct page *spage, *dpage;
+       unsigned int soff, doff;
        void *src, *dst;
-       unsigned int dlen;
+       unsigned int n;
        int ret;
 
-       if (!req->src || !req->slen || req->slen > SCOMP_SCRATCH_SIZE)
+       if (!req->src || !slen)
                return -EINVAL;
 
-       if (req->dst && !req->dlen)
+       if (!req->dst || !dlen)
                return -EINVAL;
 
-       if (!req->dlen || req->dlen > SCOMP_SCRATCH_SIZE)
-               req->dlen = SCOMP_SCRATCH_SIZE;
-
-       dlen = req->dlen;
+       soff = req->src->offset;
+       spage = nth_page(sg_page(req->src), soff / PAGE_SIZE);
+       soff = offset_in_page(soff);
 
-       scratch = raw_cpu_ptr(&scomp_scratch);
-       spin_lock_bh(&scratch->lock);
-
-       if (sg_nents(req->src) == 1 && !PageHighMem(sg_page(req->src))) {
-               src = page_to_virt(sg_page(req->src)) + req->src->offset;
-       } else {
-               scatterwalk_map_and_copy(scratch->src, req->src, 0,
-                                        req->slen, 0);
+       n = slen / PAGE_SIZE;
+       n += (offset_in_page(slen) + soff - 1) / PAGE_SIZE;
+       if (slen <= req->src->length && (!PageHighMem(nth_page(spage, n)) ||
+                                        size_add(soff, slen) <= PAGE_SIZE))
+               src = kmap_local_page(spage) + soff;
+       else
                src = scratch->src;
-       }
 
-       if (req->dst && sg_nents(req->dst) == 1 && !PageHighMem(sg_page(req->dst)))
-               dst = page_to_virt(sg_page(req->dst)) + req->dst->offset;
-       else
+       doff = req->dst->offset;
+       dpage = nth_page(sg_page(req->dst), doff / PAGE_SIZE);
+       doff = offset_in_page(doff);
+
+       n = dlen / PAGE_SIZE;
+       n += (offset_in_page(dlen) + doff - 1) / PAGE_SIZE;
+       if (dlen <= req->dst->length && (!PageHighMem(nth_page(dpage, n)) ||
+                                        size_add(doff, dlen) <= PAGE_SIZE))
+               dst = kmap_local_page(dpage) + doff;
+       else {
+               if (dlen > SCOMP_SCRATCH_SIZE)
+                       dlen = SCOMP_SCRATCH_SIZE;
                dst = scratch->dst;
+       }
+
+       spin_lock_bh(&scratch->lock);
+
+       if (src == scratch->src)
+               memcpy_from_sglist(src, req->src, 0, slen);
 
        stream = raw_cpu_ptr(crypto_scomp_alg(scomp)->stream);
        spin_lock(&stream->lock);
        if (dir)
-               ret = crypto_scomp_compress(scomp, src, req->slen,
-                                           dst, &req->dlen, stream->ctx);
+               ret = crypto_scomp_compress(scomp, src, slen,
+                                           dst, &dlen, stream->ctx);
        else
-               ret = crypto_scomp_decompress(scomp, src, req->slen,
-                                             dst, &req->dlen, stream->ctx);
+               ret = crypto_scomp_decompress(scomp, src, slen,
+                                             dst, &dlen, stream->ctx);
+
+       if (dst == scratch->dst)
+               memcpy_to_sglist(req->dst, 0, dst, dlen);
+
        spin_unlock(&stream->lock);
-       if (!ret) {
-               if (!req->dst) {
-                       req->dst = sgl_alloc(req->dlen, GFP_ATOMIC, NULL);
-                       if (!req->dst) {
-                               ret = -ENOMEM;
-                               goto out;
-                       }
-               } else if (req->dlen > dlen) {
-                       ret = -ENOSPC;
-                       goto out;
-               }
-               if (dst == scratch->dst) {
-                       scatterwalk_map_and_copy(scratch->dst, req->dst, 0,
-                                                req->dlen, 1);
-               } else {
-                       int nr_pages = DIV_ROUND_UP(req->dst->offset + req->dlen, PAGE_SIZE);
-                       int i;
-                       struct page *dst_page = sg_page(req->dst);
-
-                       for (i = 0; i < nr_pages; i++)
-                               flush_dcache_page(dst_page + i);
+       spin_unlock_bh(&scratch->lock);
+
+       req->dlen = dlen;
+
+       if (dst != scratch->dst) {
+               kunmap_local(dst);
+               dlen += doff;
+               for (;;) {
+                       flush_dcache_page(dpage);
+                       if (dlen <= PAGE_SIZE)
+                               break;
+                       dlen -= PAGE_SIZE;
+                       dpage = nth_page(dpage, 1);
                }
        }
-out:
-       spin_unlock_bh(&scratch->lock);
+       if (src != scratch->src)
+               kunmap_local(src);
+
        return ret;
 }
 
@@ -277,7 +297,6 @@ int crypto_init_scomp_ops_async(struct crypto_tfm *tfm)
 
        crt->compress = scomp_acomp_compress;
        crt->decompress = scomp_acomp_decompress;
-       crt->dst_free = sgl_free;
 
        return 0;
 }

diff --git a/include/crypto/acompress.h b/include/crypto/acompress.h
index c4d8a29274c65d3106dfd4fdd0f81078f6016377..53c9e632862b4b212f3dd53d7aeb13bdc1f0bbb6 100644 (file)
--- a/include/crypto/acompress.h
+++ b/include/crypto/acompress.h
@@ -18,8 +18,6 @@
 #include <linux/spinlock_types.h>
 #include <linux/types.h>
 
-#define CRYPTO_ACOMP_ALLOC_OUTPUT      0x00000001
-
 /* Set this bit if source is virtual address instead of SG list. */
 #define CRYPTO_ACOMP_REQ_SRC_VIRT      0x00000002
 
@@ -84,15 +82,12 @@ struct acomp_req {
  *
  * @compress:          Function performs a compress operation
  * @decompress:                Function performs a de-compress operation
- * @dst_free:          Frees destination buffer if allocated inside the
- *                     algorithm
  * @reqsize:           Context size for (de)compression requests
  * @base:              Common crypto API algorithm data structure
  */
 struct crypto_acomp {
        int (*compress)(struct acomp_req *req);
        int (*decompress)(struct acomp_req *req);
-       void (*dst_free)(struct scatterlist *dst);
        unsigned int reqsize;
        struct crypto_tfm base;
 };
@@ -261,9 +256,8 @@ static inline void acomp_request_set_callback(struct acomp_req *req,
                                              crypto_completion_t cmpl,
                                              void *data)
 {
-       u32 keep = CRYPTO_ACOMP_ALLOC_OUTPUT | CRYPTO_ACOMP_REQ_SRC_VIRT |
-                  CRYPTO_ACOMP_REQ_SRC_NONDMA | CRYPTO_ACOMP_REQ_DST_VIRT |
-                  CRYPTO_ACOMP_REQ_DST_NONDMA;
+       u32 keep = CRYPTO_ACOMP_REQ_SRC_VIRT | CRYPTO_ACOMP_REQ_SRC_NONDMA |
+                  CRYPTO_ACOMP_REQ_DST_VIRT | CRYPTO_ACOMP_REQ_DST_NONDMA;
 
        req->base.complete = cmpl;
        req->base.data = data;
@@ -297,13 +291,10 @@ static inline void acomp_request_set_params(struct acomp_req *req,
        req->slen = slen;
        req->dlen = dlen;
 
-       req->base.flags &= ~(CRYPTO_ACOMP_ALLOC_OUTPUT |
-                            CRYPTO_ACOMP_REQ_SRC_VIRT |
+       req->base.flags &= ~(CRYPTO_ACOMP_REQ_SRC_VIRT |
                             CRYPTO_ACOMP_REQ_SRC_NONDMA |
                             CRYPTO_ACOMP_REQ_DST_VIRT |
                             CRYPTO_ACOMP_REQ_DST_NONDMA);
-       if (!req->dst)
-               req->base.flags |= CRYPTO_ACOMP_ALLOC_OUTPUT;
 }
 
 /**
@@ -403,7 +394,6 @@ static inline void acomp_request_set_dst_dma(struct acomp_req *req,
        req->dvirt = dst;
        req->dlen = dlen;
 
-       req->base.flags &= ~CRYPTO_ACOMP_ALLOC_OUTPUT;
        req->base.flags &= ~CRYPTO_ACOMP_REQ_DST_NONDMA;
        req->base.flags |= CRYPTO_ACOMP_REQ_DST_VIRT;
 }
@@ -424,7 +414,6 @@ static inline void acomp_request_set_dst_nondma(struct acomp_req *req,
        req->dvirt = dst;
        req->dlen = dlen;
 
-       req->base.flags &= ~CRYPTO_ACOMP_ALLOC_OUTPUT;
        req->base.flags |= CRYPTO_ACOMP_REQ_DST_NONDMA;
        req->base.flags |= CRYPTO_ACOMP_REQ_DST_VIRT;
 }

diff --git a/include/crypto/internal/scompress.h b/include/crypto/internal/scompress.h
index 88986ab8ce15b2e72f8718fda48488a992724c1f..f25aa2ea3b4807c8f15032dec427c692ea1357b6 100644 (file)
--- a/include/crypto/internal/scompress.h
+++ b/include/crypto/internal/scompress.h
@@ -12,8 +12,6 @@
 #include <crypto/acompress.h>
 #include <crypto/algapi.h>
 
-#define SCOMP_SCRATCH_SIZE     131072
-
 struct acomp_req;
 
 struct crypto_scomp {