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-rw-r--r--kernel/relay.c162
1 files changed, 0 insertions, 162 deletions
diff --git a/kernel/relay.c b/kernel/relay.c
index 83fe0325cd..a8e90e98bf 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -1073,167 +1073,6 @@ static ssize_t relay_file_read(struct file *filp,
return written;
}
-static void relay_consume_bytes(struct rchan_buf *rbuf, int bytes_consumed)
-{
- rbuf->bytes_consumed += bytes_consumed;
-
- if (rbuf->bytes_consumed >= rbuf->chan->subbuf_size) {
- relay_subbufs_consumed(rbuf->chan, rbuf->cpu, 1);
- rbuf->bytes_consumed %= rbuf->chan->subbuf_size;
- }
-}
-
-static void relay_pipe_buf_release(struct pipe_inode_info *pipe,
- struct pipe_buffer *buf)
-{
- struct rchan_buf *rbuf;
-
- rbuf = (struct rchan_buf *)page_private(buf->page);
- relay_consume_bytes(rbuf, buf->private);
-}
-
-static const struct pipe_buf_operations relay_pipe_buf_ops = {
- .release = relay_pipe_buf_release,
- .try_steal = generic_pipe_buf_try_steal,
- .get = generic_pipe_buf_get,
-};
-
-static void relay_page_release(struct splice_pipe_desc *spd, unsigned int i)
-{
-}
-
-/*
- * subbuf_splice_actor - splice up to one subbuf's worth of data
- */
-static ssize_t subbuf_splice_actor(struct file *in,
- loff_t *ppos,
- struct pipe_inode_info *pipe,
- size_t len,
- unsigned int flags,
- int *nonpad_ret)
-{
- unsigned int pidx, poff, total_len, subbuf_pages, nr_pages;
- struct rchan_buf *rbuf = in->private_data;
- unsigned int subbuf_size = rbuf->chan->subbuf_size;
- uint64_t pos = (uint64_t) *ppos;
- uint32_t alloc_size = (uint32_t) rbuf->chan->alloc_size;
- size_t read_start = (size_t) do_div(pos, alloc_size);
- size_t read_subbuf = read_start / subbuf_size;
- size_t padding = rbuf->padding[read_subbuf];
- size_t nonpad_end = read_subbuf * subbuf_size + subbuf_size - padding;
- struct page *pages[PIPE_DEF_BUFFERS];
- struct partial_page partial[PIPE_DEF_BUFFERS];
- struct splice_pipe_desc spd = {
- .pages = pages,
- .nr_pages = 0,
- .nr_pages_max = PIPE_DEF_BUFFERS,
- .partial = partial,
- .ops = &relay_pipe_buf_ops,
- .spd_release = relay_page_release,
- };
- ssize_t ret;
-
- if (rbuf->subbufs_produced == rbuf->subbufs_consumed)
- return 0;
- if (splice_grow_spd(pipe, &spd))
- return -ENOMEM;
-
- /*
- * Adjust read len, if longer than what is available
- */
- if (len > (subbuf_size - read_start % subbuf_size))
- len = subbuf_size - read_start % subbuf_size;
-
- subbuf_pages = rbuf->chan->alloc_size >> PAGE_SHIFT;
- pidx = (read_start / PAGE_SIZE) % subbuf_pages;
- poff = read_start & ~PAGE_MASK;
- nr_pages = min_t(unsigned int, subbuf_pages, spd.nr_pages_max);
-
- for (total_len = 0; spd.nr_pages < nr_pages; spd.nr_pages++) {
- unsigned int this_len, this_end, private;
- unsigned int cur_pos = read_start + total_len;
-
- if (!len)
- break;
-
- this_len = min_t(unsigned long, len, PAGE_SIZE - poff);
- private = this_len;
-
- spd.pages[spd.nr_pages] = rbuf->page_array[pidx];
- spd.partial[spd.nr_pages].offset = poff;
-
- this_end = cur_pos + this_len;
- if (this_end >= nonpad_end) {
- this_len = nonpad_end - cur_pos;
- private = this_len + padding;
- }
- spd.partial[spd.nr_pages].len = this_len;
- spd.partial[spd.nr_pages].private = private;
-
- len -= this_len;
- total_len += this_len;
- poff = 0;
- pidx = (pidx + 1) % subbuf_pages;
-
- if (this_end >= nonpad_end) {
- spd.nr_pages++;
- break;
- }
- }
-
- ret = 0;
- if (!spd.nr_pages)
- goto out;
-
- ret = *nonpad_ret = splice_to_pipe(pipe, &spd);
- if (ret < 0 || ret < total_len)
- goto out;
-
- if (read_start + ret == nonpad_end)
- ret += padding;
-
-out:
- splice_shrink_spd(&spd);
- return ret;
-}
-
-static ssize_t relay_file_splice_read(struct file *in,
- loff_t *ppos,
- struct pipe_inode_info *pipe,
- size_t len,
- unsigned int flags)
-{
- ssize_t spliced;
- int ret;
- int nonpad_ret = 0;
-
- ret = 0;
- spliced = 0;
-
- while (len && !spliced) {
- ret = subbuf_splice_actor(in, ppos, pipe, len, flags, &nonpad_ret);
- if (ret < 0)
- break;
- else if (!ret) {
- if (flags & SPLICE_F_NONBLOCK)
- ret = -EAGAIN;
- break;
- }
-
- *ppos += ret;
- if (ret > len)
- len = 0;
- else
- len -= ret;
- spliced += nonpad_ret;
- nonpad_ret = 0;
- }
-
- if (spliced)
- return spliced;
-
- return ret;
-}
const struct file_operations relay_file_operations = {
.open = relay_file_open,
@@ -1242,6 +1081,5 @@ const struct file_operations relay_file_operations = {
.read = relay_file_read,
.llseek = no_llseek,
.release = relay_file_release,
- .splice_read = relay_file_splice_read,
};
EXPORT_SYMBOL_GPL(relay_file_operations);