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-rw-r--r--io_uring/rsrc.c60
-rw-r--r--io_uring/rsrc.h3
-rw-r--r--io_uring/rw.c60
3 files changed, 63 insertions, 60 deletions
diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c
index 68629eba4132..110608955159 100644
--- a/io_uring/rsrc.c
+++ b/io_uring/rsrc.c
@@ -1310,3 +1310,63 @@ int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
io_rsrc_node_switch(ctx, NULL);
return ret;
}
+
+int io_import_fixed(int ddir, struct iov_iter *iter,
+ struct io_mapped_ubuf *imu,
+ u64 buf_addr, size_t len)
+{
+ u64 buf_end;
+ size_t offset;
+
+ if (WARN_ON_ONCE(!imu))
+ return -EFAULT;
+ if (unlikely(check_add_overflow(buf_addr, (u64)len, &buf_end)))
+ return -EFAULT;
+ /* not inside the mapped region */
+ if (unlikely(buf_addr < imu->ubuf || buf_end > imu->ubuf_end))
+ return -EFAULT;
+
+ /*
+ * May not be a start of buffer, set size appropriately
+ * and advance us to the beginning.
+ */
+ offset = buf_addr - imu->ubuf;
+ iov_iter_bvec(iter, ddir, imu->bvec, imu->nr_bvecs, offset + len);
+
+ if (offset) {
+ /*
+ * Don't use iov_iter_advance() here, as it's really slow for
+ * using the latter parts of a big fixed buffer - it iterates
+ * over each segment manually. We can cheat a bit here, because
+ * we know that:
+ *
+ * 1) it's a BVEC iter, we set it up
+ * 2) all bvecs are PAGE_SIZE in size, except potentially the
+ * first and last bvec
+ *
+ * So just find our index, and adjust the iterator afterwards.
+ * If the offset is within the first bvec (or the whole first
+ * bvec, just use iov_iter_advance(). This makes it easier
+ * since we can just skip the first segment, which may not
+ * be PAGE_SIZE aligned.
+ */
+ const struct bio_vec *bvec = imu->bvec;
+
+ if (offset <= bvec->bv_len) {
+ iov_iter_advance(iter, offset);
+ } else {
+ unsigned long seg_skip;
+
+ /* skip first vec */
+ offset -= bvec->bv_len;
+ seg_skip = 1 + (offset >> PAGE_SHIFT);
+
+ iter->bvec = bvec + seg_skip;
+ iter->nr_segs -= seg_skip;
+ iter->count -= bvec->bv_len + offset;
+ iter->iov_offset = offset & ~PAGE_MASK;
+ }
+ }
+
+ return 0;
+}
diff --git a/io_uring/rsrc.h b/io_uring/rsrc.h
index 03f26516e994..87f58315b247 100644
--- a/io_uring/rsrc.h
+++ b/io_uring/rsrc.h
@@ -64,6 +64,9 @@ int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx,
void io_rsrc_node_switch(struct io_ring_ctx *ctx,
struct io_rsrc_data *data_to_kill);
+int io_import_fixed(int ddir, struct iov_iter *iter,
+ struct io_mapped_ubuf *imu,
+ u64 buf_addr, size_t len);
void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
int io_sqe_buffers_unregister(struct io_ring_ctx *ctx);
diff --git a/io_uring/rw.c b/io_uring/rw.c
index ded8ef01165c..e07f2670dfa8 100644
--- a/io_uring/rw.c
+++ b/io_uring/rw.c
@@ -273,66 +273,6 @@ static int kiocb_done(struct io_kiocb *req, ssize_t ret,
return IOU_ISSUE_SKIP_COMPLETE;
}
-static int io_import_fixed(int ddir, struct iov_iter *iter,
- struct io_mapped_ubuf *imu,
- u64 buf_addr, size_t len)
-{
- u64 buf_end;
- size_t offset;
-
- if (WARN_ON_ONCE(!imu))
- return -EFAULT;
- if (unlikely(check_add_overflow(buf_addr, (u64)len, &buf_end)))
- return -EFAULT;
- /* not inside the mapped region */
- if (unlikely(buf_addr < imu->ubuf || buf_end > imu->ubuf_end))
- return -EFAULT;
-
- /*
- * May not be a start of buffer, set size appropriately
- * and advance us to the beginning.
- */
- offset = buf_addr - imu->ubuf;
- iov_iter_bvec(iter, ddir, imu->bvec, imu->nr_bvecs, offset + len);
-
- if (offset) {
- /*
- * Don't use iov_iter_advance() here, as it's really slow for
- * using the latter parts of a big fixed buffer - it iterates
- * over each segment manually. We can cheat a bit here, because
- * we know that:
- *
- * 1) it's a BVEC iter, we set it up
- * 2) all bvecs are PAGE_SIZE in size, except potentially the
- * first and last bvec
- *
- * So just find our index, and adjust the iterator afterwards.
- * If the offset is within the first bvec (or the whole first
- * bvec, just use iov_iter_advance(). This makes it easier
- * since we can just skip the first segment, which may not
- * be PAGE_SIZE aligned.
- */
- const struct bio_vec *bvec = imu->bvec;
-
- if (offset <= bvec->bv_len) {
- iov_iter_advance(iter, offset);
- } else {
- unsigned long seg_skip;
-
- /* skip first vec */
- offset -= bvec->bv_len;
- seg_skip = 1 + (offset >> PAGE_SHIFT);
-
- iter->bvec = bvec + seg_skip;
- iter->nr_segs -= seg_skip;
- iter->count -= bvec->bv_len + offset;
- iter->iov_offset = offset & ~PAGE_MASK;
- }
- }
-
- return 0;
-}
-
#ifdef CONFIG_COMPAT
static ssize_t io_compat_import(struct io_kiocb *req, struct iovec *iov,
unsigned int issue_flags)