block: refactor get_contig_folio_len

[blktests-ci]

Pull request for series with
subject: block: refactor get_contig_folio_len
version: 1
url: https://patchwork.kernel.org/project/linux-block/list/?series=1042135

[blktests-ci]

Upstream branch: b543459
series: https://patchwork.kernel.org/project/linux-block/list/?series=1042135
version: 1

[blktests-ci]

Upstream branch: 944aacb
series: https://patchwork.kernel.org/project/linux-block/list/?series=1042135
version: 1

[blktests-ci]

Upstream branch: 944aacb
series: https://patchwork.kernel.org/project/linux-block/list/?series=1042135
version: 1

[blktests-ci]

Upstream branch: 944aacb
series: https://patchwork.kernel.org/project/linux-block/list/?series=1043971
version: 1

[blktests-ci]

Upstream branch: 944aacb
series: https://patchwork.kernel.org/project/linux-block/list/?series=1043971
version: 1

[blktests-ci]

Upstream branch: 944aacb
series: https://patchwork.kernel.org/project/linux-block/list/?series=1043971
version: 1

[blktests-ci]

Upstream branch: 6c79021
series: https://patchwork.kernel.org/project/linux-block/list/?series=1043971
version: 1

[blktests-ci]

Upstream branch: a66191c
series: https://patchwork.kernel.org/project/linux-block/list/?series=1043971
version: 1

[blktests-ci]

Upstream branch: a66191c
series: https://patchwork.kernel.org/project/linux-block/list/?series=1043971
version: 1

[blktests-ci]

Upstream branch: a66191c
series: https://patchwork.kernel.org/project/linux-block/list/?series=1043971
version: 1

[blktests-ci]

Upstream branch: a66191c
series: https://patchwork.kernel.org/project/linux-block/list/?series=1043971
version: 1

[blktests-ci]

Upstream branch: 05f7e89
series: https://patchwork.kernel.org/project/linux-block/list/?series=1043971
version: 1

[blktests-ci]

Upstream branch: c22e26b
series: https://patchwork.kernel.org/project/linux-block/list/?series=1043971
version: 1

Pull request is NOT updated. Failed to apply https://patchwork.kernel.org/project/linux-block/list/?series=1043971
error message:

Cmd('git') failed due to: exit code(128)
  cmdline: git am --3way
  stdout: 'Applying: block: refactor get_contig_folio_len
Using index info to reconstruct a base tree...
M	block/bio.c
Falling back to patching base and 3-way merge...
Auto-merging block/bio.c
CONFLICT (content): Merge conflict in block/bio.c
Patch failed at 0001 block: refactor get_contig_folio_len'
  stderr: 'error: Failed to merge in the changes.
hint: Use 'git am --show-current-patch=diff' to see the failed patch
hint: When you have resolved this problem, run "git am --continue".
hint: If you prefer to skip this patch, run "git am --skip" instead.
hint: To restore the original branch and stop patching, run "git am --abort".
hint: Disable this message with "git config set advice.mergeConflict false"'

conflict:

diff --cc block/bio.c
index b291b9aaeee1,18dfdaba0c73..000000000000
--- a/block/bio.c
+++ b/block/bio.c
@@@ -1206,6 -1172,114 +1206,117 @@@ void bio_iov_bvec_set(struct bio *bio, 
  	bio_set_flag(bio, BIO_CLONED);
  }
  
++<<<<<<< HEAD
++=======
+ static unsigned int get_contig_folio_len(struct page **pages,
+ 					 unsigned int *num_pages, size_t left,
+ 					 size_t offset)
+ {
+ 	struct folio *folio = page_folio(pages[0]);
+ 	size_t contig_sz = min_t(size_t, PAGE_SIZE - offset, left);
+ 	unsigned int max_pages, i;
+ 	size_t folio_offset, len;
+ 
+ 	folio_offset = PAGE_SIZE * folio_page_idx(folio, pages[0]) + offset;
+ 	len = min(folio_size(folio) - folio_offset, left);
+ 
+ 	/*
+ 	 * We might COW a single page in the middle of a large folio, so we have
+ 	 * to check that all pages belong to the same folio.
+ 	 */
+ 	left -= contig_sz;
+ 	max_pages = DIV_ROUND_UP(offset + len, PAGE_SIZE);
+ 	for (i = 1; i < max_pages; i++) {
+ 		size_t next = min_t(size_t, PAGE_SIZE, left);
+ 
+ 		if (page_folio(pages[i]) != folio ||
+ 		    pages[i] != pages[i - 1] + 1)
+ 			break;
+ 		contig_sz += next;
+ 		left -= next;
+ 	}
+ 
+ 	*num_pages = i;
+ 	return contig_sz;
+ }
+ 
+ #define PAGE_PTRS_PER_BVEC     (sizeof(struct bio_vec) / sizeof(struct page *))
+ 
+ /**
+  * __bio_iov_iter_get_pages - pin user or kernel pages and add them to a bio
+  * @bio: bio to add pages to
+  * @iter: iov iterator describing the region to be mapped
+  *
+  * Extracts pages from *iter and appends them to @bio's bvec array.  The pages
+  * will have to be cleaned up in the way indicated by the BIO_PAGE_PINNED flag.
+  * For a multi-segment *iter, this function only adds pages from the next
+  * non-empty segment of the iov iterator.
+  */
+ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter)
+ {
+ 	iov_iter_extraction_t extraction_flags = 0;
+ 	unsigned short nr_pages = bio->bi_max_vecs - bio->bi_vcnt;
+ 	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;
+ 	ssize_t size;
+ 	unsigned int i = 0;
+ 	size_t offset, left, len;
+ 	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);
+ 
+ 	if (bio->bi_bdev && blk_queue_pci_p2pdma(bio->bi_bdev->bd_disk->queue))
+ 		extraction_flags |= ITER_ALLOW_P2PDMA;
+ 
+ 	size = iov_iter_extract_pages(iter, &pages,
+ 				      UINT_MAX - bio->bi_iter.bi_size,
+ 				      nr_pages, extraction_flags, &offset);
+ 	if (unlikely(size <= 0))
+ 		return size ? size : -EFAULT;
+ 
+ 	nr_pages = DIV_ROUND_UP(offset + size, PAGE_SIZE);
+ 	for (left = size; left > 0; left -= len) {
+ 		unsigned int old_vcnt = bio->bi_vcnt;
+ 		unsigned int nr_to_add;
+ 
+ 		len = get_contig_folio_len(&pages[i], &nr_to_add, left, offset);
+ 		if (!bio_add_page(bio, pages[i], len, offset)) {
+ 			WARN_ON_ONCE(1);
+ 			ret = -EINVAL;
+ 			goto out;
+ 		}
+ 
+ 		if (bio_flagged(bio, BIO_PAGE_PINNED)) {
+ 			/*
+ 			 * We're adding another fragment of a page that already
+ 			 * was part of the last segment.  Undo our pin as the
+ 			 * page was pinned when an earlier fragment of it was
+ 			 * added to the bio and __bio_release_pages expects a
+ 			 * single pin per page.
+ 			 */
+ 			if (offset && bio->bi_vcnt == old_vcnt)
+ 				unpin_user_folio(page_folio(pages[i]), 1);
+ 		}
+ 		i += nr_to_add;
+ 		offset = 0;
+ 	}
+ 
+ 	iov_iter_revert(iter, left);
+ out:
+ 	while (i < nr_pages)
+ 		bio_release_page(bio, pages[i++]);
+ 
+ 	return ret;
+ }
+ 
++>>>>>>> block: refactor get_contig_folio_len
  /*
   * Aligns the bio size to the len_align_mask, releasing excessive bio vecs that
   * __bio_iov_iter_get_pages may have inserted, and reverts the trimmed length

[blktests-ci]

At least one diff in series https://patchwork.kernel.org/project/linux-block/list/?series=1042135 irrelevant now for [{'archived': False, 'project': 241}] search patterns