Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
io_uring/rsrc: allow cloning at an offset
Right now buffer cloning is an all-or-nothing kind of thing - either the
whole table is cloned from a source to a destination ring, or nothing at
all.
However, it's not always desired to clone the whole thing. Allow for
the application to specify a source and destination offset, and a
number of buffers to clone. If the destination offset is non-zero, then
allocate sparse nodes upfront.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
+30
-7
+4
-1
include/uapi/linux/io_uring.h
+4
-1
include/uapi/linux/io_uring.h
+26
-6
io_uring/rsrc.c
+26
-6
io_uring/rsrc.c
···
927
927
return 0;
928
928
}
929
929
930
-
static int io_clone_buffers(struct io_ring_ctx *ctx, struct io_ring_ctx *src_ctx)
930
+
static int io_clone_buffers(struct io_ring_ctx *ctx, struct io_ring_ctx *src_ctx,
931
+
struct io_uring_clone_buffers *arg)
931
932
{
933
+
int i, ret, nbufs, off, nr;
932
934
struct io_rsrc_data data;
933
-
int i, ret, nbufs;
934
935
935
936
/*
936
937
* Drop our own lock here. We'll setup the data we need and reference
···
944
943
nbufs = src_ctx->buf_table.nr;
945
944
if (!nbufs)
946
945
goto out_unlock;
947
-
ret = io_rsrc_data_alloc(&data, nbufs);
946
+
ret = -EINVAL;
947
+
if (!arg->nr)
948
+
arg->nr = nbufs;
949
+
else if (arg->nr > nbufs)
950
+
goto out_unlock;
951
+
ret = -EOVERFLOW;
952
+
if (check_add_overflow(arg->nr, arg->src_off, &off))
953
+
goto out_unlock;
954
+
if (off > nbufs)
955
+
goto out_unlock;
956
+
if (check_add_overflow(arg->nr, arg->dst_off, &off))
957
+
goto out_unlock;
958
+
ret = -EINVAL;
959
+
if (off > IORING_MAX_REG_BUFFERS)
960
+
goto out_unlock;
961
+
ret = io_rsrc_data_alloc(&data, off);
948
962
if (ret)
949
963
goto out_unlock;
950
964
951
-
for (i = 0; i < nbufs; i++) {
965
+
off = arg->dst_off;
966
+
i = arg->src_off;
967
+
nr = arg->nr;
968
+
while (nr--) {
952
969
struct io_rsrc_node *dst_node, *src_node;
953
970
954
971
src_node = io_rsrc_node_lookup(&src_ctx->buf_table, i);
···
982
963
refcount_inc(&src_node->buf->refs);
983
964
dst_node->buf = src_node->buf;
984
965
}
985
-
data.nodes[i] = dst_node;
966
+
data.nodes[off++] = dst_node;
967
+
i++;
986
968
}
987
969
988
970
/* Have a ref on the bufs now, drop src lock and re-grab our own lock */
···
1038
1018
file = io_uring_register_get_file(buf.src_fd, registered_src);
1039
1019
if (IS_ERR(file))
1040
1020
return PTR_ERR(file);
1041
-
ret = io_clone_buffers(ctx, file->private_data);
1021
+
ret = io_clone_buffers(ctx, file->private_data, &buf);
1042
1022
if (!registered_src)
1043
1023
fput(file);
1044
1024
return ret;