diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2025-04-17 10:32:32 +0100 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-04-17 06:21:13 -0600 |
| commit | 50169d07548441e3033b9bbaa06e573e7224f140 (patch) | |
| tree | 9f1ecdcb9029518799f779b31b1a824ba5b9a18f /io_uring | |
| parent | 1ac571288822253db32196c49f240739148417e3 (diff) | |
io_uring/rsrc: separate kbuf offset adjustments
Kernel registered buffers are special because segments are not uniform
in size, and we have a bunch of optimisations based on that uniformity
for normal buffers. Handle kbuf separately, it'll be cleaner this way.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/4e9e5990b0ab5aee723c0be5cd9b5bcf810375f9.1744882081.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring')
| -rw-r--r-- | io_uring/rsrc.c | 19 |
1 files changed, 7 insertions, 12 deletions
diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c index 4d62897d1c89..fddde8ffe81e 100644 --- a/io_uring/rsrc.c +++ b/io_uring/rsrc.c @@ -1048,11 +1048,14 @@ static int io_import_fixed(int ddir, struct iov_iter *iter, if (!(imu->dir & (1 << ddir))) return -EFAULT; - /* - * Might not be a start of buffer, set size appropriately - * and advance us to the beginning. - */ offset = buf_addr - imu->ubuf; + + if (imu->is_kbuf) { + iov_iter_bvec(iter, ddir, imu->bvec, imu->nr_bvecs, offset + len); + iov_iter_advance(iter, offset); + return 0; + } + iov_iter_bvec(iter, ddir, imu->bvec, imu->nr_bvecs, offset + len); /* @@ -1072,17 +1075,9 @@ static int io_import_fixed(int ddir, struct iov_iter *iter, * be folio_size aligned. */ bvec = imu->bvec; - - /* - * Kernel buffer bvecs, on the other hand, don't necessarily - * have the size property of user registered ones, so we have - * to use the slow iter advance. - */ if (offset < bvec->bv_len) { iter->count -= offset; iter->iov_offset = offset; - } else if (imu->is_kbuf) { - iov_iter_advance(iter, offset); } else { unsigned long seg_skip; |