IB: Enable FMR pool user to set page size

This patch allows the consumer to set the page size of "pages" mapped
by the pool FMRs, which is a feature already existing in the base
verbs API.  On the cosmetic side it changes ib_fmr_attr.page_size field
to be named page_shift.

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/infiniband/core/fmr_pool.c

@@ -278,9 +278,9 @@ struct ib_fmr_pool *ib_create_fmr_pool(struct ib_pd             *pd,
 	{
 		struct ib_pool_fmr *fmr;
 		struct ib_fmr_attr attr = {
-			.max_pages = params->max_pages_per_fmr,
-			.max_maps  = IB_FMR_MAX_REMAPS,
-			.page_size = PAGE_SHIFT
+			.max_pages  = params->max_pages_per_fmr,
+			.max_maps   = IB_FMR_MAX_REMAPS,
+			.page_shift = params->page_shift
 		};
 
 		for (i = 0; i < params->pool_size; ++i) {

drivers/infiniband/hw/mthca/mthca_mr.c

@@ -491,7 +491,7 @@ int mthca_fmr_alloc(struct mthca_dev *dev, u32 pd,
 	int err = -ENOMEM;
 	int i;
 
-	if (mr->attr.page_size < 12 || mr->attr.page_size >= 32)
+	if (mr->attr.page_shift < 12 || mr->attr.page_shift >= 32)
 		return -EINVAL;
 
 	/* For Arbel, all MTTs must fit in the same page. */
@@ -543,7 +543,7 @@ int mthca_fmr_alloc(struct mthca_dev *dev, u32 pd,
 				       MTHCA_MPT_FLAG_REGION      |
 				       access);
 
-	mpt_entry->page_size = cpu_to_be32(mr->attr.page_size - 12);
+	mpt_entry->page_size = cpu_to_be32(mr->attr.page_shift - 12);
 	mpt_entry->key       = cpu_to_be32(key);
 	mpt_entry->pd        = cpu_to_be32(pd);
 	memset(&mpt_entry->start, 0,
@@ -611,7 +611,7 @@ static inline int mthca_check_fmr(struct mthca_fmr *fmr, u64 *page_list,
 	if (list_len > fmr->attr.max_pages)
 		return -EINVAL;
 
-	page_mask = (1 << fmr->attr.page_size) - 1;
+	page_mask = (1 << fmr->attr.page_shift) - 1;
 
 	/* We are getting page lists, so va must be page aligned. */
 	if (iova & page_mask)
@@ -659,7 +659,7 @@ int mthca_tavor_map_phys_fmr(struct ib_fmr *ibfmr, u64 *page_list,
 	}
 
 	mpt_entry.lkey   = cpu_to_be32(key);
-	mpt_entry.length = cpu_to_be64(list_len * (1ull << fmr->attr.page_size));
+	mpt_entry.length = cpu_to_be64(list_len * (1ull << fmr->attr.page_shift));
 	mpt_entry.start  = cpu_to_be64(iova);
 
 	__raw_writel((__force u32) mpt_entry.lkey, &fmr->mem.tavor.mpt->key);
@@ -700,7 +700,7 @@ int mthca_arbel_map_phys_fmr(struct ib_fmr *ibfmr, u64 *page_list,
 
 	fmr->mem.arbel.mpt->key    = cpu_to_be32(key);
 	fmr->mem.arbel.mpt->lkey   = cpu_to_be32(key);
-	fmr->mem.arbel.mpt->length = cpu_to_be64(list_len * (1ull << fmr->attr.page_size));
+	fmr->mem.arbel.mpt->length = cpu_to_be64(list_len * (1ull << fmr->attr.page_shift));
 	fmr->mem.arbel.mpt->start  = cpu_to_be64(iova);
 
 	wmb();

include/rdma/ib_fmr_pool.h

@@ -43,6 +43,7 @@ struct ib_fmr_pool;
 /**
  * struct ib_fmr_pool_param - Parameters for creating FMR pool
  * @max_pages_per_fmr:Maximum number of pages per map request.
+ * @page_shift: Log2 of sizeof "pages" mapped by this fmr
  * @access:Access flags for FMRs in pool.
  * @pool_size:Number of FMRs to allocate for pool.
  * @dirty_watermark:Flush is triggered when @dirty_watermark dirty
@@ -55,6 +56,7 @@ struct ib_fmr_pool;
  */
 struct ib_fmr_pool_param {
 	int                     max_pages_per_fmr;
+	int                     page_shift;
 	enum ib_access_flags    access;
 	int                     pool_size;
 	int                     dirty_watermark;

include/rdma/ib_verbs.h

@@ -651,7 +651,7 @@ struct ib_mw_bind {
 struct ib_fmr_attr {
 	int	max_pages;
 	int	max_maps;
-	u8	page_size;
+	u8	page_shift;
 };
 
 struct ib_ucontext {