1 files changed, 428 insertions, 124 deletions

diff --git a/io_uring/register.c b/io_uring/register.c
index c0010a66a6f2..62d39b3ff317 100644
--- a/io_uring/register.c
+++ b/io_uring/register.c
@@ -18,6 +18,7 @@
 #include <linux/io_uring.h>
 #include <linux/io_uring_types.h>
 
+#include "filetable.h"
 #include "io_uring.h"
 #include "opdef.h"
 #include "tctx.h"
@@ -27,65 +28,15 @@
 #include "cancel.h"
 #include "kbuf.h"
 #include "napi.h"
+#include "eventfd.h"
+#include "msg_ring.h"
+#include "memmap.h"
+#include "zcrx.h"
+#include "query.h"
 
 #define IORING_MAX_RESTRICTIONS	(IORING_RESTRICTION_LAST + \
 				 IORING_REGISTER_LAST + IORING_OP_LAST)
 
-static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg,
-			       unsigned int eventfd_async)
-{
-	struct io_ev_fd *ev_fd;
-	__s32 __user *fds = arg;
-	int fd;
-
-	ev_fd = rcu_dereference_protected(ctx->io_ev_fd,
-					lockdep_is_held(&ctx->uring_lock));
-	if (ev_fd)
-		return -EBUSY;
-
-	if (copy_from_user(&fd, fds, sizeof(*fds)))
-		return -EFAULT;
-
-	ev_fd = kmalloc(sizeof(*ev_fd), GFP_KERNEL);
-	if (!ev_fd)
-		return -ENOMEM;
-
-	ev_fd->cq_ev_fd = eventfd_ctx_fdget(fd);
-	if (IS_ERR(ev_fd->cq_ev_fd)) {
-		int ret = PTR_ERR(ev_fd->cq_ev_fd);
-		kfree(ev_fd);
-		return ret;
-	}
-
-	spin_lock(&ctx->completion_lock);
-	ctx->evfd_last_cq_tail = ctx->cached_cq_tail;
-	spin_unlock(&ctx->completion_lock);
-
-	ev_fd->eventfd_async = eventfd_async;
-	ctx->has_evfd = true;
-	rcu_assign_pointer(ctx->io_ev_fd, ev_fd);
-	atomic_set(&ev_fd->refs, 1);
-	atomic_set(&ev_fd->ops, 0);
-	return 0;
-}
-
-int io_eventfd_unregister(struct io_ring_ctx *ctx)
-{
-	struct io_ev_fd *ev_fd;
-
-	ev_fd = rcu_dereference_protected(ctx->io_ev_fd,
-					lockdep_is_held(&ctx->uring_lock));
-	if (ev_fd) {
-		ctx->has_evfd = false;
-		rcu_assign_pointer(ctx->io_ev_fd, NULL);
-		if (!atomic_fetch_or(BIT(IO_EVENTFD_OP_FREE_BIT), &ev_fd->ops))
-			call_rcu(&ev_fd->rcu, io_eventfd_ops);
-		return 0;
-	}
-
-	return -ENXIO;
-}
-
 static __cold int io_probe(struct io_ring_ctx *ctx, void __user *arg,
 			   unsigned nr_args)
 {
@@ -93,27 +44,22 @@ static __cold int io_probe(struct io_ring_ctx *ctx, void __user *arg,
 	size_t size;
 	int i, ret;
 
-	size = struct_size(p, ops, nr_args);
-	if (size == SIZE_MAX)
-		return -EOVERFLOW;
-	p = kzalloc(size, GFP_KERNEL);
-	if (!p)
-		return -ENOMEM;
+	if (nr_args > IORING_OP_LAST)
+		nr_args = IORING_OP_LAST;
 
-	ret = -EFAULT;
-	if (copy_from_user(p, arg, size))
-		goto out;
+	size = struct_size(p, ops, nr_args);
+	p = memdup_user(arg, size);
+	if (IS_ERR(p))
+		return PTR_ERR(p);
 	ret = -EINVAL;
 	if (memchr_inv(p, 0, size))
 		goto out;
 
 	p->last_op = IORING_OP_LAST - 1;
-	if (nr_args > IORING_OP_LAST)
-		nr_args = IORING_OP_LAST;
 
 	for (i = 0; i < nr_args; i++) {
 		p->ops[i].op = i;
-		if (!io_issue_defs[i].not_supported)
+		if (io_uring_op_supported(i))
 			p->ops[i].flags = IO_URING_OP_SUPPORTED;
 	}
 	p->ops_len = i;
@@ -157,21 +103,13 @@ static int io_register_personality(struct io_ring_ctx *ctx)
 	return id;
 }
 
-static __cold int io_register_restrictions(struct io_ring_ctx *ctx,
-					   void __user *arg, unsigned int nr_args)
+static __cold int io_parse_restrictions(void __user *arg, unsigned int nr_args,
+					struct io_restriction *restrictions)
 {
 	struct io_uring_restriction *res;
 	size_t size;
 	int i, ret;
 
-	/* Restrictions allowed only if rings started disabled */
-	if (!(ctx->flags & IORING_SETUP_R_DISABLED))
-		return -EBADFD;
-
-	/* We allow only a single restrictions registration */
-	if (ctx->restrictions.registered)
-		return -EBUSY;
-
 	if (!arg || nr_args > IORING_MAX_RESTRICTIONS)
 		return -EINVAL;
 
@@ -183,47 +121,57 @@ static __cold int io_register_restrictions(struct io_ring_ctx *ctx,
 	if (IS_ERR(res))
 		return PTR_ERR(res);
 
-	ret = 0;
+	ret = -EINVAL;
 
 	for (i = 0; i < nr_args; i++) {
 		switch (res[i].opcode) {
 		case IORING_RESTRICTION_REGISTER_OP:
-			if (res[i].register_op >= IORING_REGISTER_LAST) {
-				ret = -EINVAL;
-				goto out;
-			}
-
-			__set_bit(res[i].register_op,
-				  ctx->restrictions.register_op);
+			if (res[i].register_op >= IORING_REGISTER_LAST)
+				goto err;
+			__set_bit(res[i].register_op, restrictions->register_op);
 			break;
 		case IORING_RESTRICTION_SQE_OP:
-			if (res[i].sqe_op >= IORING_OP_LAST) {
-				ret = -EINVAL;
-				goto out;
-			}
-
-			__set_bit(res[i].sqe_op, ctx->restrictions.sqe_op);
+			if (res[i].sqe_op >= IORING_OP_LAST)
+				goto err;
+			__set_bit(res[i].sqe_op, restrictions->sqe_op);
 			break;
 		case IORING_RESTRICTION_SQE_FLAGS_ALLOWED:
-			ctx->restrictions.sqe_flags_allowed = res[i].sqe_flags;
+			restrictions->sqe_flags_allowed = res[i].sqe_flags;
 			break;
 		case IORING_RESTRICTION_SQE_FLAGS_REQUIRED:
-			ctx->restrictions.sqe_flags_required = res[i].sqe_flags;
+			restrictions->sqe_flags_required = res[i].sqe_flags;
 			break;
 		default:
-			ret = -EINVAL;
-			goto out;
+			goto err;
 		}
 	}
 
-out:
+	ret = 0;
+
+err:
+	kfree(res);
+	return ret;
+}
+
+static __cold int io_register_restrictions(struct io_ring_ctx *ctx,
+					   void __user *arg, unsigned int nr_args)
+{
+	int ret;
+
+	/* Restrictions allowed only if rings started disabled */
+	if (!(ctx->flags & IORING_SETUP_R_DISABLED))
+		return -EBADFD;
+
+	/* We allow only a single restrictions registration */
+	if (ctx->restrictions.registered)
+		return -EBUSY;
+
+	ret = io_parse_restrictions(arg, nr_args, &ctx->restrictions);
 	/* Reset all restrictions if an error happened */
 	if (ret != 0)
 		memset(&ctx->restrictions, 0, sizeof(ctx->restrictions));
 	else
 		ctx->restrictions.registered = true;
-
-	kfree(res);
 	return ret;
 }
 
@@ -323,6 +271,8 @@ static __cold int io_register_iowq_max_workers(struct io_ring_ctx *ctx,
 	if (ctx->flags & IORING_SETUP_SQPOLL) {
 		sqd = ctx->sq_data;
 		if (sqd) {
+			struct task_struct *tsk;
+
 			/*
 			 * Observe the correct sqd->lock -> ctx->uring_lock
 			 * ordering. Fine to drop uring_lock here, we hold
@@ -332,8 +282,9 @@ static __cold int io_register_iowq_max_workers(struct io_ring_ctx *ctx,
 			mutex_unlock(&ctx->uring_lock);
 			mutex_lock(&sqd->lock);
 			mutex_lock(&ctx->uring_lock);
-			if (sqd->thread)
-				tctx = sqd->thread->io_uring;
+			tsk = sqpoll_task_locked(sqd);
+			if (tsk)
+				tctx = tsk->io_uring;
 		}
 	} else {
 		tctx = current->io_uring;
@@ -390,6 +341,271 @@ err:
 	return ret;
 }
 
+static int io_register_clock(struct io_ring_ctx *ctx,
+			     struct io_uring_clock_register __user *arg)
+{
+	struct io_uring_clock_register reg;
+
+	if (copy_from_user(&reg, arg, sizeof(reg)))
+		return -EFAULT;
+	if (memchr_inv(&reg.__resv, 0, sizeof(reg.__resv)))
+		return -EINVAL;
+
+	switch (reg.clockid) {
+	case CLOCK_MONOTONIC:
+		ctx->clock_offset = 0;
+		break;
+	case CLOCK_BOOTTIME:
+		ctx->clock_offset = TK_OFFS_BOOT;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ctx->clockid = reg.clockid;
+	return 0;
+}
+
+/*
+ * State to maintain until we can swap. Both new and old state, used for
+ * either mapping or freeing.
+ */
+struct io_ring_ctx_rings {
+	struct io_rings *rings;
+	struct io_uring_sqe *sq_sqes;
+
+	struct io_mapped_region sq_region;
+	struct io_mapped_region ring_region;
+};
+
+static void io_register_free_rings(struct io_ring_ctx *ctx,
+				   struct io_ring_ctx_rings *r)
+{
+	io_free_region(ctx->user, &r->sq_region);
+	io_free_region(ctx->user, &r->ring_region);
+}
+
+#define swap_old(ctx, o, n, field)		\
+	do {					\
+		(o).field = (ctx)->field;	\
+		(ctx)->field = (n).field;	\
+	} while (0)
+
+#define RESIZE_FLAGS	(IORING_SETUP_CQSIZE | IORING_SETUP_CLAMP)
+#define COPY_FLAGS	(IORING_SETUP_NO_SQARRAY | IORING_SETUP_SQE128 | \
+			 IORING_SETUP_CQE32 | IORING_SETUP_NO_MMAP | \
+			 IORING_SETUP_CQE_MIXED | IORING_SETUP_SQE_MIXED)
+
+static int io_register_resize_rings(struct io_ring_ctx *ctx, void __user *arg)
+{
+	struct io_ctx_config config;
+	struct io_uring_region_desc rd;
+	struct io_ring_ctx_rings o = { }, n = { }, *to_free = NULL;
+	unsigned i, tail, old_head;
+	struct io_uring_params *p = &config.p;
+	struct io_rings_layout *rl = &config.layout;
+	int ret;
+
+	memset(&config, 0, sizeof(config));
+
+	/* limited to DEFER_TASKRUN for now */
+	if (!(ctx->flags & IORING_SETUP_DEFER_TASKRUN))
+		return -EINVAL;
+	if (copy_from_user(p, arg, sizeof(*p)))
+		return -EFAULT;
+	if (p->flags & ~RESIZE_FLAGS)
+		return -EINVAL;
+
+	/* properties that are always inherited */
+	p->flags |= (ctx->flags & COPY_FLAGS);
+
+	ret = io_prepare_config(&config);
+	if (unlikely(ret))
+		return ret;
+
+	memset(&rd, 0, sizeof(rd));
+	rd.size = PAGE_ALIGN(rl->rings_size);
+	if (p->flags & IORING_SETUP_NO_MMAP) {
+		rd.user_addr = p->cq_off.user_addr;
+		rd.flags |= IORING_MEM_REGION_TYPE_USER;
+	}
+	ret = io_create_region(ctx, &n.ring_region, &rd, IORING_OFF_CQ_RING);
+	if (ret)
+		return ret;
+
+	n.rings = io_region_get_ptr(&n.ring_region);
+
+	/*
+	 * At this point n.rings is shared with userspace, just like o.rings
+	 * is as well. While we don't expect userspace to modify it while
+	 * a resize is in progress, and it's most likely that userspace will
+	 * shoot itself in the foot if it does, we can't always assume good
+	 * intent... Use read/write once helpers from here on to indicate the
+	 * shared nature of it.
+	 */
+	WRITE_ONCE(n.rings->sq_ring_mask, p->sq_entries - 1);
+	WRITE_ONCE(n.rings->cq_ring_mask, p->cq_entries - 1);
+	WRITE_ONCE(n.rings->sq_ring_entries, p->sq_entries);
+	WRITE_ONCE(n.rings->cq_ring_entries, p->cq_entries);
+
+	if (copy_to_user(arg, p, sizeof(*p))) {
+		io_register_free_rings(ctx, &n);
+		return -EFAULT;
+	}
+
+	memset(&rd, 0, sizeof(rd));
+	rd.size = PAGE_ALIGN(rl->sq_size);
+	if (p->flags & IORING_SETUP_NO_MMAP) {
+		rd.user_addr = p->sq_off.user_addr;
+		rd.flags |= IORING_MEM_REGION_TYPE_USER;
+	}
+	ret = io_create_region(ctx, &n.sq_region, &rd, IORING_OFF_SQES);
+	if (ret) {
+		io_register_free_rings(ctx, &n);
+		return ret;
+	}
+	n.sq_sqes = io_region_get_ptr(&n.sq_region);
+
+	/*
+	 * If using SQPOLL, park the thread
+	 */
+	if (ctx->sq_data) {
+		mutex_unlock(&ctx->uring_lock);
+		io_sq_thread_park(ctx->sq_data);
+		mutex_lock(&ctx->uring_lock);
+	}
+
+	/*
+	 * 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->mmap_lock as well. Likewise, hold the completion lock over the
+	 * duration of the actual swap.
+	 */
+	mutex_lock(&ctx->mmap_lock);
+	spin_lock(&ctx->completion_lock);
+	o.rings = ctx->rings;
+	ctx->rings = NULL;
+	o.sq_sqes = ctx->sq_sqes;
+	ctx->sq_sqes = NULL;
+
+	/*
+	 * Now copy SQ and CQ entries, if any. If either of the destination
+	 * rings can't hold what is already there, then fail the operation.
+	 */
+	tail = READ_ONCE(o.rings->sq.tail);
+	old_head = READ_ONCE(o.rings->sq.head);
+	if (tail - old_head > p->sq_entries)
+		goto overflow;
+	for (i = old_head; i < tail; i++) {
+		unsigned src_head = i & (ctx->sq_entries - 1);
+		unsigned dst_head = i & (p->sq_entries - 1);
+
+		n.sq_sqes[dst_head] = o.sq_sqes[src_head];
+	}
+	WRITE_ONCE(n.rings->sq.head, old_head);
+	WRITE_ONCE(n.rings->sq.tail, tail);
+
+	tail = READ_ONCE(o.rings->cq.tail);
+	old_head = READ_ONCE(o.rings->cq.head);
+	if (tail - old_head > p->cq_entries) {
+overflow:
+		/* restore old rings, and return -EOVERFLOW via cleanup path */
+		ctx->rings = o.rings;
+		ctx->sq_sqes = o.sq_sqes;
+		to_free = &n;
+		ret = -EOVERFLOW;
+		goto out;
+	}
+	for (i = old_head; i < tail; i++) {
+		unsigned src_head = i & (ctx->cq_entries - 1);
+		unsigned dst_head = i & (p->cq_entries - 1);
+
+		n.rings->cqes[dst_head] = o.rings->cqes[src_head];
+	}
+	WRITE_ONCE(n.rings->cq.head, old_head);
+	WRITE_ONCE(n.rings->cq.tail, tail);
+	/* invalidate cached cqe refill */
+	ctx->cqe_cached = ctx->cqe_sentinel = NULL;
+
+	WRITE_ONCE(n.rings->sq_dropped, READ_ONCE(o.rings->sq_dropped));
+	atomic_set(&n.rings->sq_flags, atomic_read(&o.rings->sq_flags));
+	WRITE_ONCE(n.rings->cq_flags, READ_ONCE(o.rings->cq_flags));
+	WRITE_ONCE(n.rings->cq_overflow, READ_ONCE(o.rings->cq_overflow));
+
+	/* all done, store old pointers and assign new ones */
+	if (!(ctx->flags & IORING_SETUP_NO_SQARRAY))
+		ctx->sq_array = (u32 *)((char *)n.rings + rl->sq_array_offset);
+
+	ctx->sq_entries = p->sq_entries;
+	ctx->cq_entries = p->cq_entries;
+
+	ctx->rings = n.rings;
+	ctx->sq_sqes = n.sq_sqes;
+	swap_old(ctx, o, n, ring_region);
+	swap_old(ctx, o, n, sq_region);
+	to_free = &o;
+	ret = 0;
+out:
+	spin_unlock(&ctx->completion_lock);
+	mutex_unlock(&ctx->mmap_lock);
+	io_register_free_rings(ctx, to_free);
+
+	if (ctx->sq_data)
+		io_sq_thread_unpark(ctx->sq_data);
+
+	return ret;
+}
+
+static int io_register_mem_region(struct io_ring_ctx *ctx, void __user *uarg)
+{
+	struct io_uring_mem_region_reg __user *reg_uptr = uarg;
+	struct io_uring_mem_region_reg reg;
+	struct io_uring_region_desc __user *rd_uptr;
+	struct io_uring_region_desc rd;
+	struct io_mapped_region region = {};
+	int ret;
+
+	if (io_region_is_set(&ctx->param_region))
+		return -EBUSY;
+	if (copy_from_user(&reg, reg_uptr, sizeof(reg)))
+		return -EFAULT;
+	rd_uptr = u64_to_user_ptr(reg.region_uptr);
+	if (copy_from_user(&rd, rd_uptr, sizeof(rd)))
+		return -EFAULT;
+	if (memchr_inv(&reg.__resv, 0, sizeof(reg.__resv)))
+		return -EINVAL;
+	if (reg.flags & ~IORING_MEM_REGION_REG_WAIT_ARG)
+		return -EINVAL;
+
+	/*
+	 * This ensures there are no waiters. Waiters are unlocked and it's
+	 * hard to synchronise with them, especially if we need to initialise
+	 * the region.
+	 */
+	if ((reg.flags & IORING_MEM_REGION_REG_WAIT_ARG) &&
+	    !(ctx->flags & IORING_SETUP_R_DISABLED))
+		return -EINVAL;
+
+	ret = io_create_region(ctx, &region, &rd, IORING_MAP_OFF_PARAM_REGION);
+	if (ret)
+		return ret;
+	if (copy_to_user(rd_uptr, &rd, sizeof(rd))) {
+		io_free_region(ctx->user, &region);
+		return -EFAULT;
+	}
+
+	if (reg.flags & IORING_MEM_REGION_REG_WAIT_ARG) {
+		ctx->cq_wait_arg = io_region_get_ptr(&region);
+		ctx->cq_wait_size = rd.size;
+	}
+
+	io_region_publish(ctx, &region, &ctx->param_region);
+	return 0;
+}
+
 static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
 			       void __user *arg, unsigned nr_args)
 	__releases(ctx->uring_lock)
@@ -566,6 +782,42 @@ static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
 			break;
 		ret = io_unregister_napi(ctx, arg);
 		break;
+	case IORING_REGISTER_CLOCK:
+		ret = -EINVAL;
+		if (!arg || nr_args)
+			break;
+		ret = io_register_clock(ctx, arg);
+		break;
+	case IORING_REGISTER_CLONE_BUFFERS:
+		ret = -EINVAL;
+		if (!arg || nr_args != 1)
+			break;
+		ret = io_register_clone_buffers(ctx, arg);
+		break;
+	case IORING_REGISTER_ZCRX_IFQ:
+		ret = -EINVAL;
+		if (!arg || nr_args != 1)
+			break;
+		ret = io_register_zcrx_ifq(ctx, arg);
+		break;
+	case IORING_REGISTER_RESIZE_RINGS:
+		ret = -EINVAL;
+		if (!arg || nr_args != 1)
+			break;
+		ret = io_register_resize_rings(ctx, arg);
+		break;
+	case IORING_REGISTER_MEM_REGION:
+		ret = -EINVAL;
+		if (!arg || nr_args != 1)
+			break;
+		ret = io_register_mem_region(ctx, arg);
+		break;
+	case IORING_REGISTER_QUERY:
+		ret = io_query(arg, nr_args);
+		break;
+	case IORING_REGISTER_ZCRX_CTRL:
+		ret = io_zcrx_ctrl(ctx, arg, nr_args);
+		break;
 	default:
 		ret = -EINVAL;
 		break;
@@ -574,21 +826,16 @@ static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
 	return ret;
 }
 
-SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode,
-		void __user *, arg, unsigned int, nr_args)
+/*
+ * Given an 'fd' value, return the ctx associated with if. If 'registered' is
+ * true, then the registered index is used. Otherwise, the normal fd table.
+ * Caller must call fput() on the returned file, unless it's an ERR_PTR.
+ */
+struct file *io_uring_register_get_file(unsigned int fd, bool registered)
 {
-	struct io_ring_ctx *ctx;
-	long ret = -EBADF;
 	struct file *file;
-	bool use_registered_ring;
-
-	use_registered_ring = !!(opcode & IORING_REGISTER_USE_REGISTERED_RING);
-	opcode &= ~IORING_REGISTER_USE_REGISTERED_RING;
-
-	if (opcode >= IORING_REGISTER_LAST)
-		return -EINVAL;
 
-	if (use_registered_ring) {
+	if (registered) {
 		/*
 		 * Ring fd has been registered via IORING_REGISTER_RING_FDS, we
 		 * need only dereference our task private array to find it.
@@ -596,28 +843,85 @@ SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode,
 		struct io_uring_task *tctx = current->io_uring;
 
 		if (unlikely(!tctx || fd >= IO_RINGFD_REG_MAX))
-			return -EINVAL;
+			return ERR_PTR(-EINVAL);
 		fd = array_index_nospec(fd, IO_RINGFD_REG_MAX);
 		file = tctx->registered_rings[fd];
-		if (unlikely(!file))
-			return -EBADF;
+		if (file)
+			get_file(file);
 	} else {
 		file = fget(fd);
-		if (unlikely(!file))
-			return -EBADF;
-		ret = -EOPNOTSUPP;
-		if (!io_is_uring_fops(file))
-			goto out_fput;
 	}
 
+	if (unlikely(!file))
+		return ERR_PTR(-EBADF);
+	if (io_is_uring_fops(file))
+		return file;
+	fput(file);
+	return ERR_PTR(-EOPNOTSUPP);
+}
+
+static int io_uring_register_send_msg_ring(void __user *arg, unsigned int nr_args)
+{
+	struct io_uring_sqe sqe;
+
+	if (!arg || nr_args != 1)
+		return -EINVAL;
+	if (copy_from_user(&sqe, arg, sizeof(sqe)))
+		return -EFAULT;
+	/* no flags supported */
+	if (sqe.flags)
+		return -EINVAL;
+	if (sqe.opcode != IORING_OP_MSG_RING)
+		return -EINVAL;
+
+	return io_uring_sync_msg_ring(&sqe);
+}
+
+/*
+ * "blind" registration opcodes are ones where there's no ring given, and
+ * hence the source fd must be -1.
+ */
+static int io_uring_register_blind(unsigned int opcode, void __user *arg,
+				   unsigned int nr_args)
+{
+	switch (opcode) {
+	case IORING_REGISTER_SEND_MSG_RING:
+		return io_uring_register_send_msg_ring(arg, nr_args);
+	case IORING_REGISTER_QUERY:
+		return io_query(arg, nr_args);
+	}
+	return -EINVAL;
+}
+
+SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode,
+		void __user *, arg, unsigned int, nr_args)
+{
+	struct io_ring_ctx *ctx;
+	long ret = -EBADF;
+	struct file *file;
+	bool use_registered_ring;
+
+	use_registered_ring = !!(opcode & IORING_REGISTER_USE_REGISTERED_RING);
+	opcode &= ~IORING_REGISTER_USE_REGISTERED_RING;
+
+	if (opcode >= IORING_REGISTER_LAST)
+		return -EINVAL;
+
+	if (fd == -1)
+		return io_uring_register_blind(opcode, arg, nr_args);
+
+	file = io_uring_register_get_file(fd, use_registered_ring);
+	if (IS_ERR(file))
+		return PTR_ERR(file);
 	ctx = file->private_data;
 
 	mutex_lock(&ctx->uring_lock);
 	ret = __io_uring_register(ctx, opcode, arg, nr_args);
+
+	trace_io_uring_register(ctx, opcode, ctx->file_table.data.nr,
+				ctx->buf_table.nr, ret);
 	mutex_unlock(&ctx->uring_lock);
-	trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs, ret);
-out_fput:
-	if (!use_registered_ring)
-		fput(file);
+
+	fput(file);
 	return ret;
 }