[PATCH] ethdev: fix DMA zone reserve not honoring size

From: Pavan Nikhilesh Bhagavatula <pbhagavatula@marvell.com>
To: Jerin Jacob Kollanukkaran <jerinj@marvell.com>,
	"thomas@monjalon.net" <thomas@monjalon.net>,
	"ferruh.yigit@intel.com" <ferruh.yigit@intel.com>,
	"arybchenko@solarflare.com" <arybchenko@solarflare.com>,
	"stephen@networkplumber.org" <stephen@networkplumber.org>
Cc: "dev@dpdk.org" <dev@dpdk.org>,
	Pavan Nikhilesh Bhagavatula <pbhagavatula@marvell.com>,
	"stable@dpdk.org" <stable@dpdk.org>
Subject: [PATCH] ethdev: fix DMA zone reserve not honoring size
Date: Sun, 31 Mar 2019 16:25:04 +0000	[thread overview]
Message-ID: <20190331162437.13048-1-pbhagavatula@marvell.com> (raw)

From: Pavan Nikhilesh <pbhagavatula@marvell.com>

The `rte_eth_dma_zone_reserve()` is generally used to create HW rings.
In some scenarios when a driver needs to reconfigure the ring size
since the named memzone already exists it returns the previous memzone
without checking if a different sized ring is requested.

Introduce a check to see if the ring size requested is different from the
previously created memzone length.

Fixes: 719dbebceb81 ("xen: allow determining DOM0 at runtime")
Cc: stable@dpdk.org

Signed-off-by: Pavan Nikhilesh <pbhagavatula@marvell.com>
---
 lib/librte_ethdev/rte_ethdev.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/librte_ethdev/rte_ethdev.c b/lib/librte_ethdev/rte_ethdev.c
index 12b66b68c..4ae12e43b 100644
--- a/lib/librte_ethdev/rte_ethdev.c
+++ b/lib/librte_ethdev/rte_ethdev.c
@@ -3604,9 +3604,12 @@ rte_eth_dma_zone_reserve(const struct rte_eth_dev *dev, const char *ring_name,
 	}
 
 	mz = rte_memzone_lookup(z_name);
-	if (mz)
+	if (mz && (mz->len == size))
 		return mz;
 
+	if (mz)
+		rte_memzone_free(mz);
+
 	return rte_memzone_reserve_aligned(z_name, size, socket_id,
 			RTE_MEMZONE_IOVA_CONTIG, align);
 }
-- 
2.21.0
