block/bio: remove duplicate append pages code

[ Upstream commit c58c0074c54c2e2bb3bb0d5a4d8896bb660cc8bc ]

The getting pages setup for zone append and normal IO are identical. Use
common code for each.

Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220610195830.3574005-3-kbusch@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/block/bio.c b/block/bio.c
index b117765..0dd7aa1 100644 (file)
--- a/block/bio.c
+++ b/block/bio.c
@@ -1071,6 +1071,37 @@ static void bio_put_pages(struct page **pages, size_t size, size_t off)
                put_page(pages[i]);
 }
 
+static int bio_iov_add_page(struct bio *bio, struct page *page,
+               unsigned int len, unsigned int offset)
+{
+       bool same_page = false;
+
+       if (!__bio_try_merge_page(bio, page, len, offset, &same_page)) {
+               if (WARN_ON_ONCE(bio_full(bio, len)))
+                       return -EINVAL;
+               __bio_add_page(bio, page, len, offset);
+               return 0;
+       }
+
+       if (same_page)
+               put_page(page);
+       return 0;
+}
+
+static int bio_iov_add_zone_append_page(struct bio *bio, struct page *page,
+               unsigned int len, unsigned int offset)
+{
+       struct request_queue *q = bdev_get_queue(bio->bi_bdev);
+       bool same_page = false;
+
+       if (bio_add_hw_page(q, bio, page, len, offset,
+                       queue_max_zone_append_sectors(q), &same_page) != len)
+               return -EINVAL;
+       if (same_page)
+               put_page(page);
+       return 0;
+}
+
 #define PAGE_PTRS_PER_BVEC     (sizeof(struct bio_vec) / sizeof(struct page *))
 
 /**
@@ -1089,7 +1120,6 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter)
        unsigned short entries_left = bio->bi_max_vecs - bio->bi_vcnt;
        struct bio_vec *bv = bio->bi_io_vec + bio->bi_vcnt;
        struct page **pages = (struct page **)bv;
-       bool same_page = false;
        ssize_t size, left;
        unsigned len, i;
        size_t offset;
@@ -1098,7 +1128,7 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter)
         * Move page array up in the allocated memory for the bio vecs as far as
         * possible so that we can start filling biovecs from the beginning
         * without overwriting the temporary page array.
-       */
+        */
        BUILD_BUG_ON(PAGE_PTRS_PER_BVEC < 2);
        pages += entries_left * (PAGE_PTRS_PER_BVEC - 1);
 
@@ -1108,18 +1138,18 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter)
 
        for (left = size, i = 0; left > 0; left -= len, i++) {
                struct page *page = pages[i];
+               int ret;
 
                len = min_t(size_t, PAGE_SIZE - offset, left);
+               if (bio_op(bio) == REQ_OP_ZONE_APPEND)
+                       ret = bio_iov_add_zone_append_page(bio, page, len,
+                                       offset);
+               else
+                       ret = bio_iov_add_page(bio, page, len, offset);
 
-               if (__bio_try_merge_page(bio, page, len, offset, &same_page)) {
-                       if (same_page)
-                               put_page(page);
-               } else {
-                       if (WARN_ON_ONCE(bio_full(bio, len))) {
-                               bio_put_pages(pages + i, left, offset);
-                               return -EINVAL;
-                       }
-                       __bio_add_page(bio, page, len, offset);
+               if (ret) {
+                       bio_put_pages(pages + i, left, offset);
+                       return ret;
                }
                offset = 0;
        }
@@ -1128,51 +1158,6 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter)
        return 0;
 }
 
-static int __bio_iov_append_get_pages(struct bio *bio, struct iov_iter *iter)
-{
-       unsigned short nr_pages = bio->bi_max_vecs - bio->bi_vcnt;
-       unsigned short entries_left = bio->bi_max_vecs - bio->bi_vcnt;
-       struct request_queue *q = bdev_get_queue(bio->bi_bdev);
-       unsigned int max_append_sectors = queue_max_zone_append_sectors(q);
-       struct bio_vec *bv = bio->bi_io_vec + bio->bi_vcnt;
-       struct page **pages = (struct page **)bv;
-       ssize_t size, left;
-       unsigned len, i;
-       size_t offset;
-       int ret = 0;
-
-       /*
-        * Move page array up in the allocated memory for the bio vecs as far as
-        * possible so that we can start filling biovecs from the beginning
-        * without overwriting the temporary page array.
-        */
-       BUILD_BUG_ON(PAGE_PTRS_PER_BVEC < 2);
-       pages += entries_left * (PAGE_PTRS_PER_BVEC - 1);
-
-       size = iov_iter_get_pages(iter, pages, LONG_MAX, nr_pages, &offset);
-       if (unlikely(size <= 0))
-               return size ? size : -EFAULT;
-
-       for (left = size, i = 0; left > 0; left -= len, i++) {
-               struct page *page = pages[i];
-               bool same_page = false;
-
-               len = min_t(size_t, PAGE_SIZE - offset, left);
-               if (bio_add_hw_page(q, bio, page, len, offset,
-                               max_append_sectors, &same_page) != len) {
-                       bio_put_pages(pages + i, left, offset);
-                       ret = -EINVAL;
-                       break;
-               }
-               if (same_page)
-                       put_page(page);
-               offset = 0;
-       }
-
-       iov_iter_advance(iter, size - left);
-       return ret;
-}
-
 /**
  * bio_iov_iter_get_pages - add user or kernel pages to a bio
  * @bio: bio to add pages to
@@ -1207,10 +1192,7 @@ int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter)
        }
 
        do {
-               if (bio_op(bio) == REQ_OP_ZONE_APPEND)
-                       ret = __bio_iov_append_get_pages(bio, iter);
-               else
-                       ret = __bio_iov_iter_get_pages(bio, iter);
+               ret = __bio_iov_iter_get_pages(bio, iter);
        } while (!ret && iov_iter_count(iter) && !bio_full(bio, 0));
 
        /* don't account direct I/O as memory stall */