#include <linux/wait.h>
#include <linux/sched.h>
#include <linux/cpu.h>
+#include <linux/crypto.h>
#include "zcomp.h"
-#include "zcomp_lzo.h"
-#ifdef CONFIG_ZRAM_LZ4_COMPRESS
-#include "zcomp_lz4.h"
-#endif
-static struct zcomp_backend *backends[] = {
- &zcomp_lzo,
-#ifdef CONFIG_ZRAM_LZ4_COMPRESS
- &zcomp_lz4,
+static const char * const backends[] = {
+ "lzo",
+#if IS_ENABLED(CONFIG_CRYPTO_LZ4)
+ "lz4",
+#endif
+#if IS_ENABLED(CONFIG_CRYPTO_DEFLATE)
+ "deflate",
+#endif
+#if IS_ENABLED(CONFIG_CRYPTO_LZ4HC)
+ "lz4hc",
+#endif
+#if IS_ENABLED(CONFIG_CRYPTO_842)
+ "842",
#endif
NULL
};
-static struct zcomp_backend *find_backend(const char *compress)
-{
- int i = 0;
- while (backends[i]) {
- if (sysfs_streq(compress, backends[i]->name))
- break;
- i++;
- }
- return backends[i];
-}
-
-static void zcomp_strm_free(struct zcomp *comp, struct zcomp_strm *zstrm)
+static void zcomp_strm_free(struct zcomp_strm *zstrm)
{
- if (zstrm->private)
- comp->backend->destroy(zstrm->private);
+ if (!IS_ERR_OR_NULL(zstrm->tfm))
+ crypto_free_comp(zstrm->tfm);
free_pages((unsigned long)zstrm->buffer, 1);
kfree(zstrm);
}
/*
- * allocate new zcomp_strm structure with ->private initialized by
+ * allocate new zcomp_strm structure with ->tfm initialized by
* backend, return NULL on error
*/
-static struct zcomp_strm *zcomp_strm_alloc(struct zcomp *comp, gfp_t flags)
+static struct zcomp_strm *zcomp_strm_alloc(struct zcomp *comp)
{
- struct zcomp_strm *zstrm = kmalloc(sizeof(*zstrm), flags);
+ struct zcomp_strm *zstrm = kmalloc(sizeof(*zstrm), GFP_KERNEL);
if (!zstrm)
return NULL;
- zstrm->private = comp->backend->create(flags);
+ zstrm->tfm = crypto_alloc_comp(comp->name, 0, 0);
/*
* allocate 2 pages. 1 for compressed data, plus 1 extra for the
* case when compressed size is larger than the original one
*/
- zstrm->buffer = (void *)__get_free_pages(flags | __GFP_ZERO, 1);
- if (!zstrm->private || !zstrm->buffer) {
- zcomp_strm_free(comp, zstrm);
+ zstrm->buffer = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, 1);
+ if (IS_ERR_OR_NULL(zstrm->tfm) || !zstrm->buffer) {
+ zcomp_strm_free(zstrm);
zstrm = NULL;
}
return zstrm;
}
+bool zcomp_available_algorithm(const char *comp)
+{
+ int i = 0;
+
+ while (backends[i]) {
+ if (sysfs_streq(comp, backends[i]))
+ return true;
+ i++;
+ }
+
+ /*
+ * Crypto does not ignore a trailing new line symbol,
+ * so make sure you don't supply a string containing
+ * one.
+ * This also means that we permit zcomp initialisation
+ * with any compressing algorithm known to crypto api.
+ */
+ return crypto_has_comp(comp, 0, 0) == 1;
+}
+
/* show available compressors */
ssize_t zcomp_available_show(const char *comp, char *buf)
{
+ bool known_algorithm = false;
ssize_t sz = 0;
int i = 0;
- while (backends[i]) {
- if (!strcmp(comp, backends[i]->name))
+ for (; backends[i]; i++) {
+ if (!strcmp(comp, backends[i])) {
+ known_algorithm = true;
sz += scnprintf(buf + sz, PAGE_SIZE - sz - 2,
- "[%s] ", backends[i]->name);
- else
+ "[%s] ", backends[i]);
+ } else {
sz += scnprintf(buf + sz, PAGE_SIZE - sz - 2,
- "%s ", backends[i]->name);
- i++;
+ "%s ", backends[i]);
+ }
}
+
+ /*
+ * Out-of-tree module known to crypto api or a missing
+ * entry in `backends'.
+ */
+ if (!known_algorithm && crypto_has_comp(comp, 0, 0) == 1)
+ sz += scnprintf(buf + sz, PAGE_SIZE - sz - 2,
+ "[%s] ", comp);
+
sz += scnprintf(buf + sz, PAGE_SIZE - sz, "\n");
return sz;
}
-bool zcomp_available_algorithm(const char *comp)
-{
- return find_backend(comp) != NULL;
-}
-
-struct zcomp_strm *zcomp_strm_find(struct zcomp *comp)
+struct zcomp_strm *zcomp_stream_get(struct zcomp *comp)
{
return *get_cpu_ptr(comp->stream);
}
-void zcomp_strm_release(struct zcomp *comp, struct zcomp_strm *zstrm)
+void zcomp_stream_put(struct zcomp *comp)
{
put_cpu_ptr(comp->stream);
}
-int zcomp_compress(struct zcomp *comp, struct zcomp_strm *zstrm,
- const unsigned char *src, size_t *dst_len)
+int zcomp_compress(struct zcomp_strm *zstrm,
+ const void *src, unsigned int *dst_len)
{
- return comp->backend->compress(src, zstrm->buffer, dst_len,
- zstrm->private);
+ /*
+ * Our dst memory (zstrm->buffer) is always `2 * PAGE_SIZE' sized
+ * because sometimes we can endup having a bigger compressed data
+ * due to various reasons: for example compression algorithms tend
+ * to add some padding to the compressed buffer. Speaking of padding,
+ * comp algorithm `842' pads the compressed length to multiple of 8
+ * and returns -ENOSP when the dst memory is not big enough, which
+ * is not something that ZRAM wants to see. We can handle the
+ * `compressed_size > PAGE_SIZE' case easily in ZRAM, but when we
+ * receive -ERRNO from the compressing backend we can't help it
+ * anymore. To make `842' happy we need to tell the exact size of
+ * the dst buffer, zram_drv will take care of the fact that
+ * compressed buffer is too big.
+ */
+ *dst_len = PAGE_SIZE * 2;
+
+ return crypto_comp_compress(zstrm->tfm,
+ src, PAGE_SIZE,
+ zstrm->buffer, dst_len);
}
-int zcomp_decompress(struct zcomp *comp, const unsigned char *src,
- size_t src_len, unsigned char *dst)
+int zcomp_decompress(struct zcomp_strm *zstrm,
+ const void *src, unsigned int src_len, void *dst)
{
- return comp->backend->decompress(src, src_len, dst);
+ unsigned int dst_len = PAGE_SIZE;
+
+ return crypto_comp_decompress(zstrm->tfm,
+ src, src_len,
+ dst, &dst_len);
}
static int __zcomp_cpu_notifier(struct zcomp *comp,
case CPU_UP_PREPARE:
if (WARN_ON(*per_cpu_ptr(comp->stream, cpu)))
break;
- zstrm = zcomp_strm_alloc(comp, GFP_KERNEL);
+ zstrm = zcomp_strm_alloc(comp);
if (IS_ERR_OR_NULL(zstrm)) {
pr_err("Can't allocate a compression stream\n");
return NOTIFY_BAD;
case CPU_UP_CANCELED:
zstrm = *per_cpu_ptr(comp->stream, cpu);
if (!IS_ERR_OR_NULL(zstrm))
- zcomp_strm_free(comp, zstrm);
+ zcomp_strm_free(zstrm);
*per_cpu_ptr(comp->stream, cpu) = NULL;
break;
default:
struct zcomp *zcomp_create(const char *compress)
{
struct zcomp *comp;
- struct zcomp_backend *backend;
int error;
- backend = find_backend(compress);
- if (!backend)
+ if (!zcomp_available_algorithm(compress))
return ERR_PTR(-EINVAL);
comp = kzalloc(sizeof(struct zcomp), GFP_KERNEL);
if (!comp)
return ERR_PTR(-ENOMEM);
- comp->backend = backend;
+ comp->name = compress;
error = zcomp_init(comp);
if (error) {
kfree(comp);
projects / linux-2.6-microblaze.git / blobdiff