From: Pavel Begunkov <asml.silence@gmail.com>
Date: Fri, 29 Nov 2024 13:34:27 +0000 (+0000)
Subject: io_uring/memmap: reuse io_free_region for failure path
X-Git-Tag: v6.14-rc1~201^2~50
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=226ae1b4d1111b0b0041677b58371af9b8cd31a9;p=thirdparty%2Fkernel%2Flinux.git

io_uring/memmap: reuse io_free_region for failure path

Regions are going to become more complex with allocation options and
optimisations, I want to split initialisation into steps and for that it
needs a sane fail path. Reuse io_free_region(), it's smart enough to
undo only what's needed and leaves the structure in a consistent state.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/b853b4ec407cc80d033d021bdd2c14e22378fc78.1732886067.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/io_uring/memmap.c b/io_uring/memmap.c
index fca93bc4c6f13..96c4f6b611717 100644
--- a/io_uring/memmap.c
+++ b/io_uring/memmap.c
@@ -229,7 +229,6 @@ void io_free_region(struct io_ring_ctx *ctx, struct io_mapped_region *mr)
 int io_create_region(struct io_ring_ctx *ctx, struct io_mapped_region *mr,
 		     struct io_uring_region_desc *reg)
 {
-	int pages_accounted = 0;
 	struct page **pages;
 	int nr_pages, ret;
 	void *vptr;
@@ -257,32 +256,27 @@ int io_create_region(struct io_ring_ctx *ctx, struct io_mapped_region *mr,
 		ret = __io_account_mem(ctx->user, nr_pages);
 		if (ret)
 			return ret;
-		pages_accounted = nr_pages;
 	}
+	mr->nr_pages = nr_pages;
 
 	pages = io_pin_pages(reg->user_addr, reg->size, &nr_pages);
 	if (IS_ERR(pages)) {
 		ret = PTR_ERR(pages);
-		pages = NULL;
 		goto out_free;
 	}
+	mr->pages = pages;
+	mr->flags |= IO_REGION_F_USER_PROVIDED;
 
 	vptr = vmap(pages, nr_pages, VM_MAP, PAGE_KERNEL);
 	if (!vptr) {
 		ret = -ENOMEM;
 		goto out_free;
 	}
-
-	mr->pages = pages;
 	mr->ptr = vptr;
-	mr->nr_pages = nr_pages;
-	mr->flags |= IO_REGION_F_VMAP | IO_REGION_F_USER_PROVIDED;
+	mr->flags |= IO_REGION_F_VMAP;
 	return 0;
 out_free:
-	if (pages_accounted)
-		__io_unaccount_mem(ctx->user, pages_accounted);
-	if (pages)
-		io_pages_free(&pages, nr_pages);
+	io_free_region(ctx, mr);
 	return ret;
 }