lib/raid6: Add SSSE3 optimized recovery functions

Add SSSE3 optimized recovery functions, as well as a system
for selecting the most appropriate recovery functions to use.

Originally-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Jim Kukunas <james.t.kukunas@linux.intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 37 insertions, 0 deletions

diff --git a/lib/raid6/algos.c b/lib/raid6/algos.c
index f6a0f7899163..5a7f8022be13 100644
--- a/lib/raid6/algos.c
+++ b/lib/raid6/algos.c
@@ -64,6 +64,20 @@ const struct raid6_calls * const raid6_algos[] = {
         NULL
 };
 
+void (*raid6_2data_recov)(int, size_t, int, int, void **);
+EXPORT_SYMBOL_GPL(raid6_2data_recov);
+
+void (*raid6_datap_recov)(int, size_t, int, void **);
+EXPORT_SYMBOL_GPL(raid6_datap_recov);
+
+const struct raid6_recov_calls *const raid6_recov_algos[] = {
+#if (defined(__i386__) || defined(__x86_64__)) && !defined(__arch_um__)
+        &raid6_recov_ssse3,
+#endif
+        &raid6_recov_intx1,
+        NULL
+};
+
 #ifdef __KERNEL__
 #define RAID6_TIME_JIFFIES_LG2  4
 #else
@@ -72,6 +86,26 @@ const struct raid6_calls * const raid6_algos[] = {
 #define time_before(x, y) ((x) < (y))
 #endif
 
+static inline void raid6_choose_recov(void)
+{
+        const struct raid6_recov_calls *const *algo;
+        const struct raid6_recov_calls *best;
+
+        for (best = NULL, algo = raid6_recov_algos; *algo; algo++)
+                if (!best || (*algo)->priority > best->priority)
+                        if (!(*algo)->valid || (*algo)->valid())
+                                best = *algo;
+
+        if (best) {
+                raid6_2data_recov = best->data2;
+                raid6_datap_recov = best->datap;
+
+                printk("raid6: using %s recovery algorithm\n", best->name);
+        } else
+                printk("raid6: Yikes! No recovery algorithm found!\n");
+}
+
+
 /* Try to pick the best algorithm */
 /* This code uses the gfmul table as convenient data set to abuse */
 
@@ -141,6 +175,9 @@ int __init raid6_select_algo(void)
 
         free_pages((unsigned long)syndromes, 1);
 
+        /* select raid recover functions */
+        raid6_choose_recov();
+
         return best ? 0 : -EINVAL;
 }