diff mbox series

[v4] eal: fix create user mem map repeatedly when it exists

Message ID 1607339329-624-1-git-send-email-wangyunjian@huawei.com (mailing list archive)
State New
Delegated to: David Marchand
Headers show
Series [v4] eal: fix create user mem map repeatedly when it exists | expand

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ci/travis-robot warning Travis build: failed
ci/iol-intel-Performance success Performance Testing PASS
ci/iol-intel-Functional success Functional Testing PASS
ci/iol-testing success Testing PASS
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ci/Intel-compilation success Compilation OK
ci/iol-broadcom-Functional success Functional Testing PASS
ci/checkpatch success coding style OK

Commit Message

wangyunjian Dec. 7, 2020, 11:08 a.m. UTC 
From: Yunjian Wang <wangyunjian@huawei.com>

Currently, user mem maps will check if the newly mapped area is adjacent
to any existing mapping, but will not check if the mapping is identical
because it assumes that the API will never get called with the same
mapping twice. This will result in duplicate entries in the user mem
maps list.

Fix it by also checking for duplicate mappings, and skipping them if
they are found.

Fixes: 0cbce3a167f1 ("vfio: skip DMA map failure if already mapped")
Cc: stable@dpdk.org

Signed-off-by: Yunjian Wang <wangyunjian@huawei.com>
Acked-by: Anatoly Burakov <anatoly.burakov@intel.com>
---
v4:
  Update commit log suggested by Anatoly Burakov
---
 lib/librte_eal/linux/eal_vfio.c | 5 +++++
 1 file changed, 5 insertions(+)
diff mbox series

Patch

diff --git a/lib/librte_eal/linux/eal_vfio.c b/lib/librte_eal/linux/eal_vfio.c
index 050082444e..0967215783 100644
--- a/lib/librte_eal/linux/eal_vfio.c
+++ b/lib/librte_eal/linux/eal_vfio.c
@@ -168,6 +168,10 @@  adjust_map(struct user_mem_map *src, struct user_mem_map *end,
 static int
 merge_map(struct user_mem_map *left, struct user_mem_map *right)
 {
+	/* merge the same maps into one */
+	if (memcmp(left, right, sizeof(struct user_mem_map)) == 0)
+		goto out;
+
 	if (left->addr + left->len != right->addr)
 		return 0;
 	if (left->iova + left->len != right->iova)
@@ -175,6 +179,7 @@  merge_map(struct user_mem_map *left, struct user_mem_map *right)
 
 	left->len += right->len;
 
+out:
 	memset(right, 0, sizeof(*right));
 
 	return 1;