[v2,01/18] io_uring: rename ->resize_lock

Commit Message

Pavel Begunkov Nov. 24, 2024, 9:12 p.m. UTC

->resize_lock is used for resizing rings, but it's a good idea to reuse
it in other cases as well. Rename it into mmap_lock as it's protects
from races with mmap.

Signed-off-by: Pavel Begunkov <[e-mail]>
---
 include/linux/io_uring_types.h | 2 +-
 io_uring/io_uring.c            | 2 +-
 io_uring/memmap.c              | 6 +++---
 io_uring/register.c            | 8 ++++----
 4 files changed, 9 insertions(+), 9 deletions(-)

Patch

diff --git a/include/linux/io_uring_types.h b/include/linux/io_uring_types.h
index 3e934feb3187..adb36e0da40e 100644
--- a/include/linux/io_uring_types.h
+++ b/include/linux/io_uring_types.h
@@ -423,7 +423,7 @@  struct io_ring_ctx {
 	 * side will need to grab this lock, to prevent either side from
 	 * being run concurrently with the other.
 	 */
-	struct mutex			resize_lock;
+	struct mutex			mmap_lock;
 
 	/*
 	 * If IORING_SETUP_NO_MMAP is used, then the below holds
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index bfa93888f862..fee3b7f50176 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -351,7 +351,7 @@  static __cold struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
 	INIT_WQ_LIST(&ctx->submit_state.compl_reqs);
 	INIT_HLIST_HEAD(&ctx->cancelable_uring_cmd);
 	io_napi_init(ctx);
-	mutex_init(&ctx->resize_lock);
+	mutex_init(&ctx->mmap_lock);
 
 	return ctx;
 
diff --git a/io_uring/memmap.c b/io_uring/memmap.c
index 3d71756bc598..771a57a4a16b 100644
--- a/io_uring/memmap.c
+++ b/io_uring/memmap.c
@@ -322,7 +322,7 @@  __cold int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
 	unsigned int npages;
 	void *ptr;
 
-	guard(mutex)(&ctx->resize_lock);
+	guard(mutex)(&ctx->mmap_lock);
 
 	ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz);
 	if (IS_ERR(ptr))
@@ -358,7 +358,7 @@  unsigned long io_uring_get_unmapped_area(struct file *filp, unsigned long addr,
 	if (addr)
 		return -EINVAL;
 
-	guard(mutex)(&ctx->resize_lock);
+	guard(mutex)(&ctx->mmap_lock);
 
 	ptr = io_uring_validate_mmap_request(filp, pgoff, len);
 	if (IS_ERR(ptr))
@@ -408,7 +408,7 @@  unsigned long io_uring_get_unmapped_area(struct file *file, unsigned long addr,
 	struct io_ring_ctx *ctx = file->private_data;
 	void *ptr;
 
-	guard(mutex)(&ctx->resize_lock);
+	guard(mutex)(&ctx->mmap_lock);
 
 	ptr = io_uring_validate_mmap_request(file, pgoff, len);
 	if (IS_ERR(ptr))
diff --git a/io_uring/register.c b/io_uring/register.c
index 1e99c783abdf..ba61697d7a53 100644
--- a/io_uring/register.c
+++ b/io_uring/register.c
@@ -486,15 +486,15 @@  static int io_register_resize_rings(struct io_ring_ctx *ctx, void __user *arg)
 	}
 
 	/*
-	 * We'll do the swap. Grab the ctx->resize_lock, which will exclude
+	 * We'll do the swap. Grab the ctx->mmap_lock, which will exclude
 	 * any new mmap's on the ring fd. Clear out existing mappings to prevent
 	 * mmap from seeing them, as we'll unmap them. Any attempt to mmap
 	 * existing rings beyond this point will fail. Not that it could proceed
 	 * at this point anyway, as the io_uring mmap side needs go grab the
-	 * ctx->resize_lock as well. Likewise, hold the completion lock over the
+	 * ctx->mmap_lock as well. Likewise, hold the completion lock over the
 	 * duration of the actual swap.
 	 */
-	mutex_lock(&ctx->resize_lock);
+	mutex_lock(&ctx->mmap_lock);
 	spin_lock(&ctx->completion_lock);
 	o.rings = ctx->rings;
 	ctx->rings = NULL;
@@ -561,7 +561,7 @@  static int io_register_resize_rings(struct io_ring_ctx *ctx, void __user *arg)
 	ret = 0;
 out:
 	spin_unlock(&ctx->completion_lock);
-	mutex_unlock(&ctx->resize_lock);
+	mutex_unlock(&ctx->mmap_lock);
 	io_register_free_rings(&p, to_free);
 
 	if (ctx->sq_data)