io_uring: add IORING_REGISTER_RSRC
Add a new io_uring_register() opcode for rsrc registeration. Instead of
accepting a pointer to resources, fds or iovecs, it @arg is now pointing
to a struct io_uring_rsrc_register, and the second argument tells how
large that struct is to make it easily extendible by adding new fields.
All that is done mainly to be able to pass in a pointer with tags. Pass
it in and enable CQE posting for file resources. Doesn't support setting
tags on update yet.
A design choice made here is to not post CQEs on rsrc de-registration,
but only when we updated-removed it by rsrc dynamic update.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/c498aaec32a4bb277b2406b9069662c02cdda98c.1619356238.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 36b9651..0088eee 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -7589,7 +7589,7 @@ static struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx)
}
static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
- unsigned nr_args)
+ unsigned nr_args, u64 __user *tags)
{
__s32 __user *fds = (__s32 __user *) arg;
struct file *file;
@@ -7616,17 +7616,24 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
goto out_free;
for (i = 0; i < nr_args; i++, ctx->nr_user_files++) {
- if (copy_from_user(&fd, &fds[i], sizeof(fd))) {
+ u64 tag = 0;
+
+ if ((tags && copy_from_user(&tag, &tags[i], sizeof(tag))) ||
+ copy_from_user(&fd, &fds[i], sizeof(fd))) {
ret = -EFAULT;
goto out_fput;
}
/* allow sparse sets */
- if (fd == -1)
+ if (fd == -1) {
+ ret = -EINVAL;
+ if (unlikely(tag))
+ goto out_fput;
continue;
+ }
file = fget(fd);
ret = -EBADF;
- if (!file)
+ if (unlikely(!file))
goto out_fput;
/*
@@ -7640,6 +7647,7 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
fput(file);
goto out_fput;
}
+ ctx->file_data->tags[i] = tag;
io_fixed_file_set(io_fixed_file_slot(&ctx->file_table, i), file);
}
@@ -9743,6 +9751,29 @@ static int io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
return __io_register_rsrc_update(ctx, type, &up, nr_args);
}
+static int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
+ unsigned int size)
+{
+ struct io_uring_rsrc_register rr;
+
+ /* keep it extendible */
+ if (size != sizeof(rr))
+ return -EINVAL;
+
+ memset(&rr, 0, sizeof(rr));
+ if (copy_from_user(&rr, arg, size))
+ return -EFAULT;
+ if (!rr.nr)
+ return -EINVAL;
+
+ switch (rr.type) {
+ case IORING_RSRC_FILE:
+ return io_sqe_files_register(ctx, u64_to_user_ptr(rr.data),
+ rr.nr, u64_to_user_ptr(rr.tags));
+ }
+ return -EINVAL;
+}
+
static bool io_register_op_must_quiesce(int op)
{
switch (op) {
@@ -9752,6 +9783,7 @@ static bool io_register_op_must_quiesce(int op)
case IORING_REGISTER_PROBE:
case IORING_REGISTER_PERSONALITY:
case IORING_UNREGISTER_PERSONALITY:
+ case IORING_REGISTER_RSRC:
return false;
default:
return true;
@@ -9820,7 +9852,7 @@ static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
ret = io_sqe_buffers_unregister(ctx);
break;
case IORING_REGISTER_FILES:
- ret = io_sqe_files_register(ctx, arg, nr_args);
+ ret = io_sqe_files_register(ctx, arg, nr_args, NULL);
break;
case IORING_UNREGISTER_FILES:
ret = -EINVAL;
@@ -9877,6 +9909,9 @@ static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
case IORING_REGISTER_RESTRICTIONS:
ret = io_register_restrictions(ctx, arg, nr_args);
break;
+ case IORING_REGISTER_RSRC:
+ ret = io_register_rsrc(ctx, arg, nr_args);
+ break;
default:
ret = -EINVAL;
break;