More prep work for immutable bvecs:
A few places in the code were either open coding or using the wrong
version - fix.
After we introduce the bvec iter, it'll no longer be possible to modify
the biovec through bio_for_each_segment_all() - it doesn't increment a
pointer to the current bvec, you pass in a struct bio_vec (not a
pointer) which is updated with what the current biovec would be (taking
into account bi_bvec_done and bi_size).
So because of that it's more worthwhile to be consistent about
bio_for_each_segment()/bio_for_each_segment_all() usage.
Signed-off-by: Kent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: NeilBrown <neilb@suse.de>
CC: Alasdair Kergon <agk@redhat.com>
CC: dm-devel@redhat.com
CC: Alexander Viro <viro@zeniv.linux.org.uk>
---
drivers/md/dm-crypt.c | 3 +--
drivers/md/raid1.c | 10 +++-------
fs/bio.c | 20 ++++++++++----------
fs/direct-io.c | 8 ++++----
mm/bounce.c | 2 +-
5 files changed, 19 insertions(+), 24 deletions(-)
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index bbf459b..f50798e 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -858,8 +858,7 @@ static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
unsigned int i;
struct bio_vec *bv;
- for (i = 0; i < clone->bi_vcnt; i++) {
- bv = bio_iovec_idx(clone, i);
+ bio_for_each_segment_all(bv, clone, i) {
BUG_ON(!bv->bv_page);
mempool_free(bv->bv_page, cc->page_pool);
bv->bv_page = NULL;
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index 6a96e1f..dff0473 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -921,7 +921,7 @@ static void alloc_behind_pages(struct bio *bio, struct r1bio *r1_bio)
if (unlikely(!bvecs))
return;
- bio_for_each_segment(bvec, bio, i) {
+ bio_for_each_segment_all(bvec, bio, i) {
bvecs[i] = *bvec;
bvecs[i].bv_page = alloc_page(GFP_NOIO);
if (unlikely(!bvecs[i].bv_page))
@@ -1276,12 +1276,8 @@ read_again:
struct bio_vec *bvec;
int j;
- /* Yes, I really want the '__' version so that
- * we clear any unused pointer in the io_vec, rather
- * than leave them unchanged. This is important
- * because when we come to free the pages, we won't
- * know the original bi_idx, so we just free
- * them all
+ /*
+ * We trimmed the bio, so _all is legit
*/
bio_for_each_segment_all(bvec, mbio, j)
bvec->bv_page = r1_bio->behind_bvecs[j].bv_page;
diff --git a/fs/bio.c b/fs/bio.c
index a641efd..6ba9f27 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -1546,11 +1546,11 @@ EXPORT_SYMBOL(bio_copy_kern);
*/
void bio_set_pages_dirty(struct bio *bio)
{
- struct bio_vec *bvec = bio->bi_io_vec;
+ struct bio_vec *bvec;
int i;
- for (i = 0; i < bio->bi_vcnt; i++) {
- struct page *page = bvec[i].bv_page;
+ bio_for_each_segment_all(bvec, bio, i) {
+ struct page *page = bvec->bv_page;
if (page && !PageCompound(page))
set_page_dirty_lock(page);
@@ -1559,11 +1559,11 @@ void bio_set_pages_dirty(struct bio *bio)
static void bio_release_pages(struct bio *bio)
{
- struct bio_vec *bvec = bio->bi_io_vec;
+ struct bio_vec *bvec;
int i;
- for (i = 0; i < bio->bi_vcnt; i++) {
- struct page *page = bvec[i].bv_page;
+ bio_for_each_segment_all(bvec, bio, i) {
+ struct page *page = bvec->bv_page;
if (page)
put_page(page);
@@ -1612,16 +1612,16 @@ static void bio_dirty_fn(struct work_struct *work)
void bio_check_pages_dirty(struct bio *bio)
{
- struct bio_vec *bvec = bio->bi_io_vec;
+ struct bio_vec *bvec;
int nr_clean_pages = 0;
int i;
- for (i = 0; i < bio->bi_vcnt; i++) {
- struct page *page = bvec[i].bv_page;
+ bio_for_each_segment_all(bvec, bio, i) {
+ struct page *page = bvec->bv_page;
if (PageDirty(page) || PageCompound(page)) {
page_cache_release(page);
- bvec[i].bv_page = NULL;
+ bvec->bv_page = NULL;
} else {
nr_clean_pages++;
}
diff --git a/fs/direct-io.c b/fs/direct-io.c
index f86c720..6089916 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -441,8 +441,8 @@ static struct bio *dio_await_one(struct dio *dio)
static int dio_bio_complete(struct dio *dio, struct bio *bio)
{
const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
- struct bio_vec *bvec = bio->bi_io_vec;
- int page_no;
+ struct bio_vec *bvec;
+ unsigned i;
if (!uptodate)
dio->io_error = -EIO;
@@ -450,8 +450,8 @@ static int dio_bio_complete(struct dio *dio, struct bio *bio)
if (dio->is_async && dio->rw == READ) {
bio_check_pages_dirty(bio); /* transfers ownership */
} else {
- for (page_no = 0; page_no < bio->bi_vcnt; page_no++) {
- struct page *page = bvec[page_no].bv_page;
+ bio_for_each_segment_all(bvec, bio, i) {
+ struct page *page = bvec->bv_page;
if (dio->rw == READ && !PageCompound(page))
set_page_dirty_lock(page);
diff --git a/mm/bounce.c b/mm/bounce.c
index 89324e2..bd7079a 100644
--- a/mm/bounce.c
+++ b/mm/bounce.c
@@ -194,7 +194,7 @@ static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig,
bounce:
bio = bio_clone_bioset(*bio_orig, GFP_NOIO, fs_bio_set);
- bio_for_each_segment(to, bio, i) {
+ bio_for_each_segment_all(to, bio, i) {
struct page *page = to->bv_page;
if (page_to_pfn(page) <= queue_bounce_pfn(q))
--
1.7.12
--
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block: Convert some code to bio_for_each_segment_all()
