From: Daisuke Matsuda <dskmtsd@gmail.com>
Date: Wed, 11 Jun 2025 16:27:58 +0000 (+0000)
Subject: RDMA/rxe: Remove redundant page presence check
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c81fef22020c7467c08929330009c7c613e5ff5c;p=thirdparty%2Flinux.git

RDMA/rxe: Remove redundant page presence check

hmm_pfn_to_page() does not return NULL. ib_umem_odp_map_dma_and_lock()
should return an error in case the target pages cannot be mapped until
timeout, so these checks can safely be removed.

Reviewed-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Signed-off-by: Daisuke Matsuda <dskmtsd@gmail.com>
Link: https://patch.msgid.link/20250611162758.10000-1-dskmtsd@gmail.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>
---

diff --git a/drivers/infiniband/sw/rxe/rxe_odp.c b/drivers/infiniband/sw/rxe/rxe_odp.c
index 6313680e9d40d..01a59d3f8ed47 100644
--- a/drivers/infiniband/sw/rxe/rxe_odp.c
+++ b/drivers/infiniband/sw/rxe/rxe_odp.c
@@ -203,8 +203,6 @@ static int __rxe_odp_mr_copy(struct rxe_mr *mr, u64 iova, void *addr,
 
 		page = hmm_pfn_to_page(umem_odp->map.pfn_list[idx]);
 		user_va = kmap_local_page(page);
-		if (!user_va)
-			return -EFAULT;
 
 		src = (dir == RXE_TO_MR_OBJ) ? addr : user_va;
 		dest = (dir == RXE_TO_MR_OBJ) ? user_va : addr;
@@ -283,17 +281,15 @@ static enum resp_states rxe_odp_do_atomic_op(struct rxe_mr *mr, u64 iova,
 		return RESPST_ERR_RKEY_VIOLATION;
 	}
 
-	idx = rxe_odp_iova_to_index(umem_odp, iova);
 	page_offset = rxe_odp_iova_to_page_offset(umem_odp, iova);
-	page = hmm_pfn_to_page(umem_odp->map.pfn_list[idx]);
-	if (!page)
-		return RESPST_ERR_RKEY_VIOLATION;
-
 	if (unlikely(page_offset & 0x7)) {
 		rxe_dbg_mr(mr, "iova not aligned\n");
 		return RESPST_ERR_MISALIGNED_ATOMIC;
 	}
 
+	idx = rxe_odp_iova_to_index(umem_odp, iova);
+	page = hmm_pfn_to_page(umem_odp->map.pfn_list[idx]);
+
 	va = kmap_local_page(page);
 
 	spin_lock_bh(&atomic_ops_lock);
@@ -352,10 +348,6 @@ int rxe_odp_flush_pmem_iova(struct rxe_mr *mr, u64 iova,
 		page_offset = rxe_odp_iova_to_page_offset(umem_odp, iova);
 
 		page = hmm_pfn_to_page(umem_odp->map.pfn_list[index]);
-		if (!page) {
-			mutex_unlock(&umem_odp->umem_mutex);
-			return -EFAULT;
-		}
 
 		bytes = min_t(unsigned int, length,
 			      mr_page_size(mr) - page_offset);
@@ -396,12 +388,6 @@ enum resp_states rxe_odp_do_atomic_write(struct rxe_mr *mr, u64 iova, u64 value)
 		return RESPST_ERR_RKEY_VIOLATION;
 
 	page_offset = rxe_odp_iova_to_page_offset(umem_odp, iova);
-	index = rxe_odp_iova_to_index(umem_odp, iova);
-	page = hmm_pfn_to_page(umem_odp->map.pfn_list[index]);
-	if (!page) {
-		mutex_unlock(&umem_odp->umem_mutex);
-		return RESPST_ERR_RKEY_VIOLATION;
-	}
 	/* See IBA A19.4.2 */
 	if (unlikely(page_offset & 0x7)) {
 		mutex_unlock(&umem_odp->umem_mutex);
@@ -409,6 +395,9 @@ enum resp_states rxe_odp_do_atomic_write(struct rxe_mr *mr, u64 iova, u64 value)
 		return RESPST_ERR_MISALIGNED_ATOMIC;
 	}
 
+	index = rxe_odp_iova_to_index(umem_odp, iova);
+	page = hmm_pfn_to_page(umem_odp->map.pfn_list[index]);
+
 	va = kmap_local_page(page);
 	/* Do atomic write after all prior operations have completed */
 	smp_store_release(&va[page_offset >> 3], value);