1 files changed, 171 insertions, 51 deletions

diff --git a/drivers/infiniband/hw/ehca/ipz_pt_fn.c b/drivers/infiniband/hw/ehca/ipz_pt_fn.c
index 9606f13ed092..a090c679c397 100644
--- a/drivers/infiniband/hw/ehca/ipz_pt_fn.c
+++ b/drivers/infiniband/hw/ehca/ipz_pt_fn.c
@@ -40,6 +40,11 @@
 
 #include "ehca_tools.h"
 #include "ipz_pt_fn.h"
+#include "ehca_classes.h"
+
+#define PAGES_PER_KPAGE (PAGE_SIZE >> EHCA_PAGESHIFT)
+
+struct kmem_cache *small_qp_cache;
 
 void *ipz_qpageit_get_inc(struct ipz_queue *queue)
 {
@@ -49,7 +54,7 @@ void *ipz_qpageit_get_inc(struct ipz_queue *queue)
 		queue->current_q_offset -= queue->pagesize;
 		ret = NULL;
 	}
-	if (((u64)ret) % EHCA_PAGESIZE) {
+	if (((u64)ret) % queue->pagesize) {
 		ehca_gen_err("ERROR!! not at PAGE-Boundary");
 		return NULL;
 	}
@@ -83,80 +88,195 @@ int ipz_queue_abs_to_offset(struct ipz_queue *queue, u64 addr, u64 *q_offset)
 	return -EINVAL;
 }
 
-int ipz_queue_ctor(struct ipz_queue *queue,
-		   const u32 nr_of_pages,
-		   const u32 pagesize, const u32 qe_size, const u32 nr_of_sg)
+#if PAGE_SHIFT < EHCA_PAGESHIFT
+#error Kernel pages must be at least as large than eHCA pages (4K) !
+#endif
+
+/*
+ * allocate pages for queue:
+ * outer loop allocates whole kernel pages (page aligned) and
+ * inner loop divides a kernel page into smaller hca queue pages
+ */
+static int alloc_queue_pages(struct ipz_queue *queue, const u32 nr_of_pages)
 {
-	int pages_per_kpage = PAGE_SIZE >> EHCA_PAGESHIFT;
-	int f;
+	int k, f = 0;
+	u8 *kpage;
 
-	if (pagesize > PAGE_SIZE) {
-		ehca_gen_err("FATAL ERROR: pagesize=%x is greater "
-			     "than kernel page size", pagesize);
-		return 0;
-	}
-	if (!pages_per_kpage) {
-		ehca_gen_err("FATAL ERROR: invalid kernel page size. "
-			     "pages_per_kpage=%x", pages_per_kpage);
-		return 0;
-	}
-	queue->queue_length = nr_of_pages * pagesize;
-	queue->queue_pages = vmalloc(nr_of_pages * sizeof(void *));
-	if (!queue->queue_pages) {
-		ehca_gen_err("ERROR!! didn't get the memory");
-		return 0;
-	}
-	memset(queue->queue_pages, 0, nr_of_pages * sizeof(void *));
-	/*
-	 * allocate pages for queue:
-	 * outer loop allocates whole kernel pages (page aligned) and
-	 * inner loop divides a kernel page into smaller hca queue pages
-	 */
-	f = 0;
 	while (f < nr_of_pages) {
-		u8 *kpage = (u8 *)get_zeroed_page(GFP_KERNEL);
-		int k;
+		kpage = (u8 *)get_zeroed_page(GFP_KERNEL);
 		if (!kpage)
-			goto ipz_queue_ctor_exit0; /*NOMEM*/
-		for (k = 0; k < pages_per_kpage && f < nr_of_pages; k++) {
-			(queue->queue_pages)[f] = (struct ipz_page *)kpage;
+			goto out;
+
+		for (k = 0; k < PAGES_PER_KPAGE && f < nr_of_pages; k++) {
+			queue->queue_pages[f] = (struct ipz_page *)kpage;
 			kpage += EHCA_PAGESIZE;
 			f++;
 		}
 	}
+	return 1;
 
-	queue->current_q_offset = 0;
+out:
+	for (f = 0; f < nr_of_pages && queue->queue_pages[f];
+	     f += PAGES_PER_KPAGE)
+		free_page((unsigned long)(queue->queue_pages)[f]);
+	return 0;
+}
+
+static int alloc_small_queue_page(struct ipz_queue *queue, struct ehca_pd *pd)
+{
+	int order = ilog2(queue->pagesize) - 9;
+	struct ipz_small_queue_page *page;
+	unsigned long bit;
+
+	mutex_lock(&pd->lock);
+
+	if (!list_empty(&pd->free[order]))
+		page = list_entry(pd->free[order].next,
+				  struct ipz_small_queue_page, list);
+	else {
+		page = kmem_cache_zalloc(small_qp_cache, GFP_KERNEL);
+		if (!page)
+			goto out;
+
+		page->page = get_zeroed_page(GFP_KERNEL);
+		if (!page->page) {
+			kmem_cache_free(small_qp_cache, page);
+			goto out;
+		}
+
+		list_add(&page->list, &pd->free[order]);
+	}
+
+	bit = find_first_zero_bit(page->bitmap, IPZ_SPAGE_PER_KPAGE >> order);
+	__set_bit(bit, page->bitmap);
+	page->fill++;
+
+	if (page->fill == IPZ_SPAGE_PER_KPAGE >> order)
+		list_move(&page->list, &pd->full[order]);
+
+	mutex_unlock(&pd->lock);
+
+	queue->queue_pages[0] = (void *)(page->page | (bit << (order + 9)));
+	queue->small_page = page;
+	return 1;
+
+out:
+	ehca_err(pd->ib_pd.device, "failed to allocate small queue page");
+	return 0;
+}
+
+static void free_small_queue_page(struct ipz_queue *queue, struct ehca_pd *pd)
+{
+	int order = ilog2(queue->pagesize) - 9;
+	struct ipz_small_queue_page *page = queue->small_page;
+	unsigned long bit;
+	int free_page = 0;
+
+	bit = ((unsigned long)queue->queue_pages[0] & PAGE_MASK)
+		>> (order + 9);
+
+	mutex_lock(&pd->lock);
+
+	__clear_bit(bit, page->bitmap);
+	page->fill--;
+
+	if (page->fill == 0) {
+		list_del(&page->list);
+		free_page = 1;
+	}
+
+	if (page->fill == (IPZ_SPAGE_PER_KPAGE >> order) - 1)
+		/* the page was full until we freed the chunk */
+		list_move_tail(&page->list, &pd->free[order]);
+
+	mutex_unlock(&pd->lock);
+
+	if (free_page) {
+		free_page(page->page);
+		kmem_cache_free(small_qp_cache, page);
+	}
+}
+
+int ipz_queue_ctor(struct ehca_pd *pd, struct ipz_queue *queue,
+		   const u32 nr_of_pages, const u32 pagesize,
+		   const u32 qe_size, const u32 nr_of_sg,
+		   int is_small)
+{
+	if (pagesize > PAGE_SIZE) {
+		ehca_gen_err("FATAL ERROR: pagesize=%x "
+			     "is greater than kernel page size", pagesize);
+		return 0;
+	}
+
+	/* init queue fields */
+	queue->queue_length = nr_of_pages * pagesize;
+	queue->pagesize = pagesize;
 	queue->qe_size = qe_size;
 	queue->act_nr_of_sg = nr_of_sg;
-	queue->pagesize = pagesize;
+	queue->current_q_offset = 0;
 	queue->toggle_state = 1;
-	return 1;
+	queue->small_page = NULL;
 
- ipz_queue_ctor_exit0:
-	ehca_gen_err("Couldn't get alloc pages queue=%p f=%x nr_of_pages=%x",
-		     queue, f, nr_of_pages);
-	for (f = 0; f < nr_of_pages; f += pages_per_kpage) {
-		if (!(queue->queue_pages)[f])
-			break;
-		free_page((unsigned long)(queue->queue_pages)[f]);
+	/* allocate queue page pointers */
+	queue->queue_pages = vmalloc(nr_of_pages * sizeof(void *));
+	if (!queue->queue_pages) {
+		ehca_gen_err("Couldn't allocate queue page list");
+		return 0;
 	}
+	memset(queue->queue_pages, 0, nr_of_pages * sizeof(void *));
+
+	/* allocate actual queue pages */
+	if (is_small) {
+		if (!alloc_small_queue_page(queue, pd))
+			goto ipz_queue_ctor_exit0;
+	} else
+		if (!alloc_queue_pages(queue, nr_of_pages))
+			goto ipz_queue_ctor_exit0;
+
+	return 1;
+
+ipz_queue_ctor_exit0:
+	ehca_gen_err("Couldn't alloc pages queue=%p "
+		 "nr_of_pages=%x",  queue, nr_of_pages);
+	vfree(queue->queue_pages);
+
 	return 0;
 }
 
-int ipz_queue_dtor(struct ipz_queue *queue)
+int ipz_queue_dtor(struct ehca_pd *pd, struct ipz_queue *queue)
 {
-	int pages_per_kpage = PAGE_SIZE >> EHCA_PAGESHIFT;
-	int g;
-	int nr_pages;
+	int i, nr_pages;
 
 	if (!queue || !queue->queue_pages) {
 		ehca_gen_dbg("queue or queue_pages is NULL");
 		return 0;
 	}
-	nr_pages = queue->queue_length / queue->pagesize;
-	for (g = 0; g < nr_pages; g += pages_per_kpage)
-		free_page((unsigned long)(queue->queue_pages)[g]);
+
+	if (queue->small_page)
+		free_small_queue_page(queue, pd);
+	else {
+		nr_pages = queue->queue_length / queue->pagesize;
+		for (i = 0; i < nr_pages; i += PAGES_PER_KPAGE)
+			free_page((unsigned long)queue->queue_pages[i]);
+	}
+
 	vfree(queue->queue_pages);
 
 	return 1;
 }
+
+int ehca_init_small_qp_cache(void)
+{
+	small_qp_cache = kmem_cache_create("ehca_cache_small_qp",
+					   sizeof(struct ipz_small_queue_page),
+					   0, SLAB_HWCACHE_ALIGN, NULL);
+	if (!small_qp_cache)
+		return -ENOMEM;
+
+	return 0;
+}
+
+void ehca_cleanup_small_qp_cache(void)
+{
+	kmem_cache_destroy(small_qp_cache);
+}