[PATCH 1/3] io_uring: free memory immediately when io_mem_alloc failed

[Jackie Liu <liuyun01@xxxxxxxxxx>]

In extreme cases, memory may not be available. so we should
be clean up memory.

Signed-off-by: Jackie Liu <liuyun01@xxxxxxxxxx>
---
 fs/io_uring.c | 25 +++++++++++++++++++------
 1 file changed, 19 insertions(+), 6 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 310f8d1..4430429 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -2951,6 +2951,7 @@ static int io_allocate_scq_urings(struct io_ring_ctx *ctx,
 	struct io_sq_ring *sq_ring;
 	struct io_cq_ring *cq_ring;
 	size_t size;
+	int ret;
 
 	sq_ring = io_mem_alloc(struct_size(sq_ring, array, p->sq_entries));
 	if (!sq_ring)
@@ -2963,16 +2964,22 @@ static int io_allocate_scq_urings(struct io_ring_ctx *ctx,
 	ctx->sq_entries = sq_ring->ring_entries;
 
 	size = array_size(sizeof(struct io_uring_sqe), p->sq_entries);
-	if (size == SIZE_MAX)
-		return -EOVERFLOW;
+	if (size == SIZE_MAX) {
+		ret = -EOVERFLOW;
+		goto err;
+	}
 
 	ctx->sq_sqes = io_mem_alloc(size);
-	if (!ctx->sq_sqes)
-		return -ENOMEM;
+	if (!ctx->sq_sqes) {
+		ret = -ENOMEM;
+		goto err;
+	}
 
 	cq_ring = io_mem_alloc(struct_size(cq_ring, cqes, p->cq_entries));
-	if (!cq_ring)
-		return -ENOMEM;
+	if (!cq_ring) {
+		ret = -ENOMEM;
+		goto err1;
+	}
 
 	ctx->cq_ring = cq_ring;
 	cq_ring->ring_mask = p->cq_entries - 1;
@@ -2980,6 +2987,12 @@ static int io_allocate_scq_urings(struct io_ring_ctx *ctx,
 	ctx->cq_mask = cq_ring->ring_mask;
 	ctx->cq_entries = cq_ring->ring_entries;
 	return 0;
+
+err1:
+	io_mem_free(ctx->sq_sqes);
+err:
+	io_mem_free(ctx->sq_ring);
+	return ret;
 }
 
 /*
-- 
2.7.4