From: David Howells <dhowells@redhat.com>
To: Pavel Begunkov <asml.silence@gmail.com>,
Matthew Wilcox <willy@infradead.org>,
Jens Axboe <axboe@kernel.dk>,
Alexander Viro <viro@zeniv.linux.org.uk>
Cc: dhowells@redhat.com,
Linus Torvalds <torvalds@linux-foundation.org>,
linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: [PATCH 04/29] iov_iter: Split the iterate_and_advance() macro
Date: Sat, 21 Nov 2020 14:13:53 +0000 [thread overview]
Message-ID: <160596803388.154728.17090770115276211012.stgit@warthog.procyon.org.uk> (raw)
In-Reply-To: <160596800145.154728.7192318545120181269.stgit@warthog.procyon.org.uk>
Split the iterate_and_advance() macro into iovec, bvec, kvec and discard
variants. It doesn't handle pipes.
Signed-off-by: David Howells <dhowells@redhat.com>
---
lib/iov_iter.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 62 insertions(+)
diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 280b5c9c9a9c..a221e7771201 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -147,6 +147,68 @@ static inline bool page_copy_sane(struct page *page, size_t offset, size_t n);
} \
}
+#define iterate_and_advance_iovec(i, n, v, CMD) { \
+ if (unlikely(i->count < n)) \
+ n = i->count; \
+ if (i->count) { \
+ size_t skip = i->iov_offset; \
+ const struct iovec *iov; \
+ struct iovec v; \
+ iterate_iovec(i, n, v, iov, skip, (CMD)) \
+ if (skip == iov->iov_len) { \
+ iov++; \
+ skip = 0; \
+ } \
+ i->nr_segs -= iov - i->iov; \
+ i->iov = iov; \
+ i->count -= n; \
+ i->iov_offset = skip; \
+ } \
+}
+
+#define iterate_and_advance_bvec(i, n, v, CMD) { \
+ if (unlikely(i->count < n)) \
+ n = i->count; \
+ if (i->count) { \
+ size_t skip = i->iov_offset; \
+ const struct bio_vec *bvec = i->bvec; \
+ struct bio_vec v; \
+ struct bvec_iter __bi; \
+ iterate_bvec(i, n, v, __bi, skip, (CMD)) \
+ i->bvec = __bvec_iter_bvec(i->bvec, __bi); \
+ i->nr_segs -= i->bvec - bvec; \
+ skip = __bi.bi_bvec_done; \
+ i->count -= n; \
+ i->iov_offset = skip; \
+ } \
+}
+
+#define iterate_and_advance_kvec(i, n, v, CMD) { \
+ if (unlikely(i->count < n)) \
+ n = i->count; \
+ if (i->count) { \
+ size_t skip = i->iov_offset; \
+ const struct kvec *kvec; \
+ struct kvec v; \
+ iterate_kvec(i, n, v, kvec, skip, (CMD)) \
+ if (skip == kvec->iov_len) { \
+ kvec++; \
+ skip = 0; \
+ } \
+ i->nr_segs -= kvec - i->kvec; \
+ i->kvec = kvec; \
+ i->count -= n; \
+ i->iov_offset = skip; \
+ } \
+}
+
+#define iterate_and_advance_discard(i, n) { \
+ if (unlikely(i->count < n)) \
+ n = i->count; \
+ i->count -= n; \
+ i->iov_offset += n; \
+}
+
static int copyout(void __user *to, const void *from, size_t n)
{
if (should_fail_usercopy())
next prev parent reply other threads:[~2020-11-21 14:14 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-21 14:13 [PATCH 00/29] RFC: iov_iter: Switch to using an ops table David Howells
2020-11-21 14:13 ` [PATCH 01/29] iov_iter: Switch to using a table of operations David Howells
2020-11-21 14:31 ` Pavel Begunkov
2020-11-23 23:21 ` Pavel Begunkov
2020-11-21 18:21 ` Linus Torvalds
2020-12-11 1:30 ` Al Viro
2020-11-22 13:33 ` David Howells
2020-11-22 13:58 ` David Laight
2020-11-22 19:22 ` Linus Torvalds
2020-11-22 22:34 ` David Laight
2020-11-22 22:46 ` David Laight
2020-11-23 8:05 ` Christoph Hellwig
2020-11-23 10:31 ` David Howells
2020-11-23 23:42 ` Pavel Begunkov
2020-11-24 12:50 ` David Howells
2020-11-24 15:30 ` Jens Axboe
2020-11-27 17:14 ` David Howells
2020-11-23 11:14 ` David Howells
[not found] ` <20201203064536.GE27350@xsang-OptiPlex-9020>
2020-12-03 17:47 ` [iov_iter] 9bd0e337c6: will-it-scale.per_process_ops -4.8% regression Linus Torvalds
2020-12-03 17:50 ` Jens Axboe
2020-12-04 11:50 ` David Howells
2020-12-04 11:51 ` David Howells
2020-12-07 13:10 ` Oliver Sang
2020-12-07 13:20 ` David Howells
2020-11-21 14:13 ` [PATCH 02/29] iov_iter: Split copy_page_to_iter() David Howells
2020-11-21 14:13 ` [PATCH 03/29] iov_iter: Split iov_iter_fault_in_readable David Howells
2020-11-21 14:13 ` David Howells [this message]
2020-11-21 14:14 ` [PATCH 05/29] iov_iter: Split copy_to_iter() David Howells
2020-11-21 14:14 ` [PATCH 06/29] iov_iter: Split copy_mc_to_iter() David Howells
2020-11-21 14:14 ` [PATCH 07/29] iov_iter: Split copy_from_iter() David Howells
2020-11-21 14:14 ` [PATCH 08/29] iov_iter: Split the iterate_all_kinds() macro David Howells
2020-11-21 14:14 ` [PATCH 09/29] iov_iter: Split copy_from_iter_full() David Howells
2020-11-21 14:14 ` [PATCH 10/29] iov_iter: Split copy_from_iter_nocache() David Howells
2020-11-21 14:14 ` [PATCH 11/29] iov_iter: Split copy_from_iter_flushcache() David Howells
2020-11-21 14:14 ` [PATCH 12/29] iov_iter: Split copy_from_iter_full_nocache() David Howells
2020-11-21 14:15 ` [PATCH 13/29] iov_iter: Split copy_page_from_iter() David Howells
2020-11-21 14:15 ` [PATCH 14/29] iov_iter: Split iov_iter_zero() David Howells
2020-11-21 14:15 ` [PATCH 15/29] iov_iter: Split copy_from_user_atomic() David Howells
2020-11-21 14:15 ` [PATCH 16/29] iov_iter: Split iov_iter_advance() David Howells
2020-11-21 14:15 ` [PATCH 17/29] iov_iter: Split iov_iter_revert() David Howells
2020-11-21 14:15 ` [PATCH 18/29] iov_iter: Split iov_iter_single_seg_count() David Howells
2020-11-21 14:15 ` [PATCH 19/29] iov_iter: Split iov_iter_alignment() David Howells
2020-11-21 14:15 ` [PATCH 20/29] iov_iter: Split iov_iter_gap_alignment() David Howells
2020-11-21 14:16 ` [PATCH 21/29] iov_iter: Split iov_iter_get_pages() David Howells
2020-11-21 14:16 ` [PATCH 22/29] iov_iter: Split iov_iter_get_pages_alloc() David Howells
2020-11-21 14:16 ` [PATCH 23/29] iov_iter: Split csum_and_copy_from_iter() David Howells
2020-11-21 14:16 ` [PATCH 24/29] iov_iter: Split csum_and_copy_from_iter_full() David Howells
2020-11-21 14:16 ` [PATCH 25/29] iov_iter: Split csum_and_copy_to_iter() David Howells
2020-11-21 14:16 ` [PATCH 26/29] iov_iter: Split iov_iter_npages() David Howells
2020-11-21 14:16 ` [PATCH 27/29] iov_iter: Split dup_iter() David Howells
2020-11-21 14:17 ` [PATCH 28/29] iov_iter: Split iov_iter_for_each_range() David Howells
2020-11-21 14:17 ` [PATCH 29/29] iov_iter: Remove iterate_all_kinds() and iterate_and_advance() David Howells
2020-11-21 14:34 ` [PATCH 00/29] RFC: iov_iter: Switch to using an ops table Pavel Begunkov
2020-11-21 18:23 ` Linus Torvalds
2020-12-11 3:24 ` Matthew Wilcox
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