From patchwork Wed Nov 22 23:28:13 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kent Overstreet X-Patchwork-Id: 13465570 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="VxJK6+vY" Received: from out-182.mta0.migadu.com (out-182.mta0.migadu.com [91.218.175.182]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ACD781AE for ; Wed, 22 Nov 2023 15:28:28 -0800 (PST) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1700695705; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=zIWvHSEXAsZLcU747aoInY3P5sNDUSBqxSseDMdKVmg=; b=VxJK6+vYdRQTRhBaLlGqi0/QBDPByeZMiJ4WmyCzKstlm/JOj6YCTX1iZfd8Z8TZgGf81C 7mIkqTCeozykOlu7ECRLWBOpra1KwCWkXfd72knU7zUM8MiftHjaPMN9FkRBGSbJh9aDBp Zm3yJ4zs5MT9z1ehwtfccDuo3SgQ3WI= From: Kent Overstreet To: axboe@kernel.dk, linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org Cc: Kent Overstreet , Ming Lei , Phillip Lougher Subject: [PATCH 1/3] block: Rework bio_for_each_segment_all() Date: Wed, 22 Nov 2023 18:28:13 -0500 Message-ID: <20231122232818.178256-1-kent.overstreet@linux.dev> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT This patch reworks bio_for_each_segment_all() to be more inline with how the other bio iterators work: - bio_iter_all_peek() now returns a synthesized bio_vec; we don't stash one in the iterator and pass a pointer to it - bad. This way makes it clearer what's a constructed value vs. a reference to something pre-existing, and it also will help with cleaning up and consolidating code with bio_for_each_folio_all(). - We now provide bio_for_each_segment_all_continue(), for squashfs: this makes their code clearer. Signed-off-by: Kent Overstreet Cc: Jens Axboe Cc: linux-block@vger.kernel.org Cc: Ming Lei Cc: Phillip Lougher Signed-off-by: Kent Overstreet Reviewed-by: Ming Lei --- block/bio.c | 38 ++++++++++++------------ block/blk-map.c | 38 ++++++++++++------------ block/bounce.c | 12 ++++---- drivers/md/bcache/btree.c | 8 ++--- drivers/md/raid1.c | 4 +-- fs/bcachefs/io_write.c | 6 ++-- fs/btrfs/disk-io.c | 4 +-- fs/btrfs/extent_io.c | 46 ++++++++++++++-------------- fs/btrfs/raid56.c | 14 ++++----- fs/erofs/zdata.c | 4 +-- fs/f2fs/data.c | 20 ++++++------- fs/gfs2/lops.c | 10 +++---- fs/gfs2/meta_io.c | 8 ++--- fs/squashfs/block.c | 52 ++++++++++++++++++-------------- fs/squashfs/lz4_wrapper.c | 17 ++++++----- fs/squashfs/lzo_wrapper.c | 17 ++++++----- fs/squashfs/xz_wrapper.c | 19 ++++++------ fs/squashfs/zlib_wrapper.c | 18 ++++++----- fs/squashfs/zstd_wrapper.c | 19 ++++++------ include/linux/bio.h | 34 ++++++++++++++++----- include/linux/bvec.h | 61 ++++++++++++++++++++++---------------- 21 files changed, 246 insertions(+), 203 deletions(-) diff --git a/block/bio.c b/block/bio.c index 816d412c06e9..83efe4114b84 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1145,13 +1145,13 @@ EXPORT_SYMBOL(bio_add_folio); void __bio_release_pages(struct bio *bio, bool mark_dirty) { - struct bvec_iter_all iter_all; - struct bio_vec *bvec; + struct bvec_iter_all iter; + struct bio_vec bvec; - bio_for_each_segment_all(bvec, bio, iter_all) { - if (mark_dirty && !PageCompound(bvec->bv_page)) - set_page_dirty_lock(bvec->bv_page); - bio_release_page(bio, bvec->bv_page); + bio_for_each_segment_all(bvec, bio, iter) { + if (mark_dirty && !PageCompound(bvec.bv_page)) + set_page_dirty_lock(bvec.bv_page); + bio_release_page(bio, bvec.bv_page); } } EXPORT_SYMBOL_GPL(__bio_release_pages); @@ -1427,11 +1427,11 @@ EXPORT_SYMBOL(bio_copy_data); void bio_free_pages(struct bio *bio) { - struct bio_vec *bvec; - struct bvec_iter_all iter_all; + struct bvec_iter_all iter; + struct bio_vec bvec; - bio_for_each_segment_all(bvec, bio, iter_all) - __free_page(bvec->bv_page); + bio_for_each_segment_all(bvec, bio, iter) + __free_page(bvec.bv_page); } EXPORT_SYMBOL(bio_free_pages); @@ -1466,12 +1466,12 @@ EXPORT_SYMBOL(bio_free_pages); */ void bio_set_pages_dirty(struct bio *bio) { - struct bio_vec *bvec; - struct bvec_iter_all iter_all; + struct bvec_iter_all iter; + struct bio_vec bvec; - bio_for_each_segment_all(bvec, bio, iter_all) { - if (!PageCompound(bvec->bv_page)) - set_page_dirty_lock(bvec->bv_page); + bio_for_each_segment_all(bvec, bio, iter) { + if (!PageCompound(bvec.bv_page)) + set_page_dirty_lock(bvec.bv_page); } } EXPORT_SYMBOL_GPL(bio_set_pages_dirty); @@ -1515,12 +1515,12 @@ static void bio_dirty_fn(struct work_struct *work) void bio_check_pages_dirty(struct bio *bio) { - struct bio_vec *bvec; + struct bvec_iter_all iter; + struct bio_vec bvec; unsigned long flags; - struct bvec_iter_all iter_all; - bio_for_each_segment_all(bvec, bio, iter_all) { - if (!PageDirty(bvec->bv_page) && !PageCompound(bvec->bv_page)) + bio_for_each_segment_all(bvec, bio, iter) { + if (!PageDirty(bvec.bv_page) && !PageCompound(bvec.bv_page)) goto defer; } diff --git a/block/blk-map.c b/block/blk-map.c index 8584babf3ea0..1f35f840beb8 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -47,21 +47,21 @@ static struct bio_map_data *bio_alloc_map_data(struct iov_iter *data, */ static int bio_copy_from_iter(struct bio *bio, struct iov_iter *iter) { - struct bio_vec *bvec; - struct bvec_iter_all iter_all; + struct bvec_iter_all bv_iter; + struct bio_vec bvec; - bio_for_each_segment_all(bvec, bio, iter_all) { + bio_for_each_segment_all(bvec, bio, bv_iter) { ssize_t ret; - ret = copy_page_from_iter(bvec->bv_page, - bvec->bv_offset, - bvec->bv_len, + ret = copy_page_from_iter(bvec.bv_page, + bvec.bv_offset, + bvec.bv_len, iter); if (!iov_iter_count(iter)) break; - if (ret < bvec->bv_len) + if (ret < bvec.bv_len) return -EFAULT; } @@ -78,21 +78,21 @@ static int bio_copy_from_iter(struct bio *bio, struct iov_iter *iter) */ static int bio_copy_to_iter(struct bio *bio, struct iov_iter iter) { - struct bio_vec *bvec; - struct bvec_iter_all iter_all; + struct bvec_iter_all bv_iter; + struct bio_vec bvec; - bio_for_each_segment_all(bvec, bio, iter_all) { + bio_for_each_segment_all(bvec, bio, bv_iter) { ssize_t ret; - ret = copy_page_to_iter(bvec->bv_page, - bvec->bv_offset, - bvec->bv_len, + ret = copy_page_to_iter(bvec.bv_page, + bvec.bv_offset, + bvec.bv_len, &iter); if (!iov_iter_count(&iter)) break; - if (ret < bvec->bv_len) + if (ret < bvec.bv_len) return -EFAULT; } @@ -442,12 +442,12 @@ static void bio_copy_kern_endio(struct bio *bio) static void bio_copy_kern_endio_read(struct bio *bio) { char *p = bio->bi_private; - struct bio_vec *bvec; - struct bvec_iter_all iter_all; + struct bvec_iter_all iter; + struct bio_vec bvec; - bio_for_each_segment_all(bvec, bio, iter_all) { - memcpy_from_bvec(p, bvec); - p += bvec->bv_len; + bio_for_each_segment_all(bvec, bio, iter) { + memcpy_from_bvec(p, &bvec); + p += bvec.bv_len; } bio_copy_kern_endio(bio); diff --git a/block/bounce.c b/block/bounce.c index 7cfcb242f9a1..e701832d76c4 100644 --- a/block/bounce.c +++ b/block/bounce.c @@ -102,18 +102,18 @@ static void copy_to_high_bio_irq(struct bio *to, struct bio *from) static void bounce_end_io(struct bio *bio) { struct bio *bio_orig = bio->bi_private; - struct bio_vec *bvec, orig_vec; + struct bio_vec bvec, orig_vec; struct bvec_iter orig_iter = bio_orig->bi_iter; - struct bvec_iter_all iter_all; + struct bvec_iter_all iter; /* * free up bounce indirect pages used */ - bio_for_each_segment_all(bvec, bio, iter_all) { + bio_for_each_segment_all(bvec, bio, iter) { orig_vec = bio_iter_iovec(bio_orig, orig_iter); - if (bvec->bv_page != orig_vec.bv_page) { - dec_zone_page_state(bvec->bv_page, NR_BOUNCE); - mempool_free(bvec->bv_page, &page_pool); + if (bvec.bv_page != orig_vec.bv_page) { + dec_zone_page_state(bvec.bv_page, NR_BOUNCE); + mempool_free(bvec.bv_page, &page_pool); } bio_advance_iter(bio_orig, &orig_iter, orig_vec.bv_len); } diff --git a/drivers/md/bcache/btree.c b/drivers/md/bcache/btree.c index 9441eac3d546..db9bed575e60 100644 --- a/drivers/md/bcache/btree.c +++ b/drivers/md/bcache/btree.c @@ -373,12 +373,12 @@ static void do_btree_node_write(struct btree *b) bset_sector_offset(&b->keys, i)); if (!bch_bio_alloc_pages(b->bio, __GFP_NOWARN|GFP_NOWAIT)) { - struct bio_vec *bv; + struct bio_vec bv; void *addr = (void *) ((unsigned long) i & ~(PAGE_SIZE - 1)); - struct bvec_iter_all iter_all; + struct bvec_iter_all iter; - bio_for_each_segment_all(bv, b->bio, iter_all) { - memcpy(page_address(bv->bv_page), addr, PAGE_SIZE); + bio_for_each_segment_all(bv, b->bio, iter) { + memcpy(page_address(bv.bv_page), addr, PAGE_SIZE); addr += PAGE_SIZE; } diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 35d12948e0a9..9c8df78895d3 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -2184,7 +2184,7 @@ static void process_checks(struct r1bio *r1_bio) blk_status_t status = sbio->bi_status; struct page **ppages = get_resync_pages(pbio)->pages; struct page **spages = get_resync_pages(sbio)->pages; - struct bio_vec *bi; + struct bio_vec bi; int page_len[RESYNC_PAGES] = { 0 }; struct bvec_iter_all iter_all; @@ -2194,7 +2194,7 @@ static void process_checks(struct r1bio *r1_bio) sbio->bi_status = 0; bio_for_each_segment_all(bi, sbio, iter_all) - page_len[j++] = bi->bv_len; + page_len[j++] = bi.bv_len; if (!status) { for (j = vcnt; j-- ; ) { diff --git a/fs/bcachefs/io_write.c b/fs/bcachefs/io_write.c index d6bd8f788d3a..99960c028598 100644 --- a/fs/bcachefs/io_write.c +++ b/fs/bcachefs/io_write.c @@ -98,11 +98,11 @@ void bch2_latency_acct(struct bch_dev *ca, u64 submit_time, int rw) void bch2_bio_free_pages_pool(struct bch_fs *c, struct bio *bio) { struct bvec_iter_all iter; - struct bio_vec *bv; + struct bio_vec bv; bio_for_each_segment_all(bv, bio, iter) - if (bv->bv_page != ZERO_PAGE(0)) - mempool_free(bv->bv_page, &c->bio_bounce_pages); + if (bv.bv_page != ZERO_PAGE(0)) + mempool_free(bv.bv_page, &c->bio_bounce_pages); bio->bi_vcnt = 0; } diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 401ea09ae4b8..3c5538792528 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -3620,12 +3620,12 @@ ALLOW_ERROR_INJECTION(open_ctree, ERRNO); static void btrfs_end_super_write(struct bio *bio) { struct btrfs_device *device = bio->bi_private; - struct bio_vec *bvec; + struct bio_vec bvec; struct bvec_iter_all iter_all; struct page *page; bio_for_each_segment_all(bvec, bio, iter_all) { - page = bvec->bv_page; + page = bvec.bv_page; if (bio->bi_status) { btrfs_warn_rl_in_rcu(device->fs_info, diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 03cef28d9e37..3e79d3041cb1 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -460,27 +460,27 @@ static void end_bio_extent_writepage(struct btrfs_bio *bbio) { struct bio *bio = &bbio->bio; int error = blk_status_to_errno(bio->bi_status); - struct bio_vec *bvec; + struct bio_vec bvec; struct bvec_iter_all iter_all; ASSERT(!bio_flagged(bio, BIO_CLONED)); bio_for_each_segment_all(bvec, bio, iter_all) { - struct page *page = bvec->bv_page; + struct page *page = bvec.bv_page; struct inode *inode = page->mapping->host; struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); const u32 sectorsize = fs_info->sectorsize; - u64 start = page_offset(page) + bvec->bv_offset; - u32 len = bvec->bv_len; + u64 start = page_offset(page) + bvec.bv_offset; + u32 len = bvec.bv_len; /* Our read/write should always be sector aligned. */ - if (!IS_ALIGNED(bvec->bv_offset, sectorsize)) + if (!IS_ALIGNED(bvec.bv_offset, sectorsize)) btrfs_err(fs_info, "partial page write in btrfs with offset %u and length %u", - bvec->bv_offset, bvec->bv_len); - else if (!IS_ALIGNED(bvec->bv_len, sectorsize)) + bvec.bv_offset, bvec.bv_len); + else if (!IS_ALIGNED(bvec.bv_len, sectorsize)) btrfs_info(fs_info, "incomplete page write with offset %u and length %u", - bvec->bv_offset, bvec->bv_len); + bvec.bv_offset, bvec.bv_len); btrfs_finish_ordered_extent(bbio->ordered, page, start, len, !error); if (error) @@ -584,7 +584,7 @@ static void begin_page_read(struct btrfs_fs_info *fs_info, struct page *page) static void end_bio_extent_readpage(struct btrfs_bio *bbio) { struct bio *bio = &bbio->bio; - struct bio_vec *bvec; + struct bio_vec bvec; struct processed_extent processed = { 0 }; /* * The offset to the beginning of a bio, since one bio can never be @@ -596,7 +596,7 @@ static void end_bio_extent_readpage(struct btrfs_bio *bbio) ASSERT(!bio_flagged(bio, BIO_CLONED)); bio_for_each_segment_all(bvec, bio, iter_all) { bool uptodate = !bio->bi_status; - struct page *page = bvec->bv_page; + struct page *page = bvec.bv_page; struct inode *inode = page->mapping->host; struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); const u32 sectorsize = fs_info->sectorsize; @@ -616,19 +616,19 @@ static void end_bio_extent_readpage(struct btrfs_bio *bbio) * for unaligned offsets, and an error if they don't add up to * a full sector. */ - if (!IS_ALIGNED(bvec->bv_offset, sectorsize)) + if (!IS_ALIGNED(bvec.bv_offset, sectorsize)) btrfs_err(fs_info, "partial page read in btrfs with offset %u and length %u", - bvec->bv_offset, bvec->bv_len); - else if (!IS_ALIGNED(bvec->bv_offset + bvec->bv_len, + bvec.bv_offset, bvec.bv_len); + else if (!IS_ALIGNED(bvec.bv_offset + bvec.bv_len, sectorsize)) btrfs_info(fs_info, "incomplete page read with offset %u and length %u", - bvec->bv_offset, bvec->bv_len); + bvec.bv_offset, bvec.bv_len); - start = page_offset(page) + bvec->bv_offset; - end = start + bvec->bv_len - 1; - len = bvec->bv_len; + start = page_offset(page) + bvec.bv_offset; + end = start + bvec.bv_len - 1; + len = bvec.bv_len; if (likely(uptodate)) { loff_t i_size = i_size_read(inode); @@ -1608,7 +1608,7 @@ static void extent_buffer_write_end_io(struct btrfs_bio *bbio) struct btrfs_fs_info *fs_info = eb->fs_info; bool uptodate = !bbio->bio.bi_status; struct bvec_iter_all iter_all; - struct bio_vec *bvec; + struct bio_vec bvec; u32 bio_offset = 0; if (!uptodate) @@ -1616,8 +1616,8 @@ static void extent_buffer_write_end_io(struct btrfs_bio *bbio) bio_for_each_segment_all(bvec, &bbio->bio, iter_all) { u64 start = eb->start + bio_offset; - struct page *page = bvec->bv_page; - u32 len = bvec->bv_len; + struct page *page = bvec.bv_page; + u32 len = bvec.bv_len; btrfs_page_clear_writeback(fs_info, page, start, len); bio_offset += len; @@ -3871,7 +3871,7 @@ static void extent_buffer_read_end_io(struct btrfs_bio *bbio) struct btrfs_fs_info *fs_info = eb->fs_info; bool uptodate = !bbio->bio.bi_status; struct bvec_iter_all iter_all; - struct bio_vec *bvec; + struct bio_vec bvec; u32 bio_offset = 0; eb->read_mirror = bbio->mirror_num; @@ -3889,8 +3889,8 @@ static void extent_buffer_read_end_io(struct btrfs_bio *bbio) bio_for_each_segment_all(bvec, &bbio->bio, iter_all) { u64 start = eb->start + bio_offset; - struct page *page = bvec->bv_page; - u32 len = bvec->bv_len; + struct page *page = bvec.bv_page; + u32 len = bvec.bv_len; if (uptodate) btrfs_page_set_uptodate(fs_info, page, start, len); diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c index 3e014b9370a3..d78a3b0eb061 100644 --- a/fs/btrfs/raid56.c +++ b/fs/btrfs/raid56.c @@ -1389,7 +1389,7 @@ static struct sector_ptr *find_stripe_sector(struct btrfs_raid_bio *rbio, static void set_bio_pages_uptodate(struct btrfs_raid_bio *rbio, struct bio *bio) { const u32 sectorsize = rbio->bioc->fs_info->sectorsize; - struct bio_vec *bvec; + struct bio_vec bvec; struct bvec_iter_all iter_all; ASSERT(!bio_flagged(bio, BIO_CLONED)); @@ -1398,9 +1398,9 @@ static void set_bio_pages_uptodate(struct btrfs_raid_bio *rbio, struct bio *bio) struct sector_ptr *sector; int pgoff; - for (pgoff = bvec->bv_offset; pgoff - bvec->bv_offset < bvec->bv_len; + for (pgoff = bvec.bv_offset; pgoff - bvec.bv_offset < bvec.bv_len; pgoff += sectorsize) { - sector = find_stripe_sector(rbio, bvec->bv_page, pgoff); + sector = find_stripe_sector(rbio, bvec.bv_page, pgoff); ASSERT(sector); if (sector) sector->uptodate = 1; @@ -1454,7 +1454,7 @@ static void verify_bio_data_sectors(struct btrfs_raid_bio *rbio, { struct btrfs_fs_info *fs_info = rbio->bioc->fs_info; int total_sector_nr = get_bio_sector_nr(rbio, bio); - struct bio_vec *bvec; + struct bio_vec bvec; struct bvec_iter_all iter_all; /* No data csum for the whole stripe, no need to verify. */ @@ -1468,8 +1468,8 @@ static void verify_bio_data_sectors(struct btrfs_raid_bio *rbio, bio_for_each_segment_all(bvec, bio, iter_all) { int bv_offset; - for (bv_offset = bvec->bv_offset; - bv_offset < bvec->bv_offset + bvec->bv_len; + for (bv_offset = bvec.bv_offset; + bv_offset < bvec.bv_offset + bvec.bv_len; bv_offset += fs_info->sectorsize, total_sector_nr++) { u8 csum_buf[BTRFS_CSUM_SIZE]; u8 *expected_csum = rbio->csum_buf + @@ -1480,7 +1480,7 @@ static void verify_bio_data_sectors(struct btrfs_raid_bio *rbio, if (!test_bit(total_sector_nr, rbio->csum_bitmap)) continue; - ret = btrfs_check_sector_csum(fs_info, bvec->bv_page, + ret = btrfs_check_sector_csum(fs_info, bvec.bv_page, bv_offset, csum_buf, expected_csum); if (ret < 0) set_bit(total_sector_nr, rbio->error_bitmap); diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c index a7e6847f6f8f..b1803b2e7044 100644 --- a/fs/erofs/zdata.c +++ b/fs/erofs/zdata.c @@ -1601,11 +1601,11 @@ static void z_erofs_decompressqueue_endio(struct bio *bio) { struct z_erofs_decompressqueue *q = bio->bi_private; blk_status_t err = bio->bi_status; - struct bio_vec *bvec; + struct bio_vec bvec; struct bvec_iter_all iter_all; bio_for_each_segment_all(bvec, bio, iter_all) { - struct page *page = bvec->bv_page; + struct page *page = bvec.bv_page; DBG_BUGON(PageUptodate(page)); DBG_BUGON(z_erofs_page_is_invalidated(page)); diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 4e42b5f24deb..12091118d6d3 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -139,12 +139,12 @@ struct bio_post_read_ctx { */ static void f2fs_finish_read_bio(struct bio *bio, bool in_task) { - struct bio_vec *bv; + struct bio_vec bv; struct bvec_iter_all iter_all; struct bio_post_read_ctx *ctx = bio->bi_private; bio_for_each_segment_all(bv, bio, iter_all) { - struct page *page = bv->bv_page; + struct page *page = bv.bv_page; if (f2fs_is_compressed_page(page)) { if (ctx && !ctx->decompression_attempted) @@ -189,11 +189,11 @@ static void f2fs_verify_bio(struct work_struct *work) * as those were handled separately by f2fs_end_read_compressed_page(). */ if (may_have_compressed_pages) { - struct bio_vec *bv; + struct bio_vec bv; struct bvec_iter_all iter_all; bio_for_each_segment_all(bv, bio, iter_all) { - struct page *page = bv->bv_page; + struct page *page = bv.bv_page; if (!f2fs_is_compressed_page(page) && !fsverity_verify_page(page)) { @@ -241,13 +241,13 @@ static void f2fs_verify_and_finish_bio(struct bio *bio, bool in_task) static void f2fs_handle_step_decompress(struct bio_post_read_ctx *ctx, bool in_task) { - struct bio_vec *bv; + struct bio_vec bv; struct bvec_iter_all iter_all; bool all_compressed = true; block_t blkaddr = ctx->fs_blkaddr; bio_for_each_segment_all(bv, ctx->bio, iter_all) { - struct page *page = bv->bv_page; + struct page *page = bv.bv_page; if (f2fs_is_compressed_page(page)) f2fs_end_read_compressed_page(page, false, blkaddr, @@ -327,7 +327,7 @@ static void f2fs_read_end_io(struct bio *bio) static void f2fs_write_end_io(struct bio *bio) { struct f2fs_sb_info *sbi; - struct bio_vec *bvec; + struct bio_vec bvec; struct bvec_iter_all iter_all; iostat_update_and_unbind_ctx(bio); @@ -337,7 +337,7 @@ static void f2fs_write_end_io(struct bio *bio) bio->bi_status = BLK_STS_IOERR; bio_for_each_segment_all(bvec, bio, iter_all) { - struct page *page = bvec->bv_page; + struct page *page = bvec.bv_page; enum count_type type = WB_DATA_TYPE(page); if (page_private_dummy(page)) { @@ -594,7 +594,7 @@ static void __submit_merged_bio(struct f2fs_bio_info *io) static bool __has_merged_page(struct bio *bio, struct inode *inode, struct page *page, nid_t ino) { - struct bio_vec *bvec; + struct bio_vec bvec; struct bvec_iter_all iter_all; if (!bio) @@ -604,7 +604,7 @@ static bool __has_merged_page(struct bio *bio, struct inode *inode, return true; bio_for_each_segment_all(bvec, bio, iter_all) { - struct page *target = bvec->bv_page; + struct page *target = bvec.bv_page; if (fscrypt_is_bounce_page(target)) { target = fscrypt_pagecache_page(target); diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c index 483f69807062..47302e7dd048 100644 --- a/fs/gfs2/lops.c +++ b/fs/gfs2/lops.c @@ -202,7 +202,7 @@ static void gfs2_end_log_write_bh(struct gfs2_sbd *sdp, static void gfs2_end_log_write(struct bio *bio) { struct gfs2_sbd *sdp = bio->bi_private; - struct bio_vec *bvec; + struct bio_vec bvec; struct page *page; struct bvec_iter_all iter_all; @@ -217,9 +217,9 @@ static void gfs2_end_log_write(struct bio *bio) } bio_for_each_segment_all(bvec, bio, iter_all) { - page = bvec->bv_page; + page = bvec.bv_page; if (page_has_buffers(page)) - gfs2_end_log_write_bh(sdp, bvec, bio->bi_status); + gfs2_end_log_write_bh(sdp, &bvec, bio->bi_status); else mempool_free(page, gfs2_page_pool); } @@ -395,11 +395,11 @@ static void gfs2_log_write_page(struct gfs2_sbd *sdp, struct page *page) static void gfs2_end_log_read(struct bio *bio) { struct page *page; - struct bio_vec *bvec; + struct bio_vec bvec; struct bvec_iter_all iter_all; bio_for_each_segment_all(bvec, bio, iter_all) { - page = bvec->bv_page; + page = bvec.bv_page; if (bio->bi_status) { int err = blk_status_to_errno(bio->bi_status); diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c index 25ceb0805df2..45947fb469ef 100644 --- a/fs/gfs2/meta_io.c +++ b/fs/gfs2/meta_io.c @@ -188,15 +188,15 @@ struct buffer_head *gfs2_meta_new(struct gfs2_glock *gl, u64 blkno) static void gfs2_meta_read_endio(struct bio *bio) { - struct bio_vec *bvec; + struct bio_vec bvec; struct bvec_iter_all iter_all; bio_for_each_segment_all(bvec, bio, iter_all) { - struct page *page = bvec->bv_page; + struct page *page = bvec.bv_page; struct buffer_head *bh = page_buffers(page); - unsigned int len = bvec->bv_len; + unsigned int len = bvec.bv_len; - while (bh_offset(bh) < bvec->bv_offset) + while (bh_offset(bh) < bvec.bv_offset) bh = bh->b_this_page; do { struct buffer_head *next = bh->b_this_page; diff --git a/fs/squashfs/block.c b/fs/squashfs/block.c index 581ce9519339..a152cef81cb0 100644 --- a/fs/squashfs/block.c +++ b/fs/squashfs/block.c @@ -35,30 +35,33 @@ static int copy_bio_to_actor(struct bio *bio, int offset, int req_length) { void *actor_addr; - struct bvec_iter_all iter_all = {}; - struct bio_vec *bvec = bvec_init_iter_all(&iter_all); + struct bvec_iter_all iter; + struct bio_vec bvec; int copied_bytes = 0; int actor_offset = 0; + int bytes_to_copy; squashfs_actor_nobuff(actor); actor_addr = squashfs_first_page(actor); - if (WARN_ON_ONCE(!bio_next_segment(bio, &iter_all))) - return 0; + bvec_iter_all_init(&iter); + bio_iter_all_advance(bio, &iter, offset); - while (copied_bytes < req_length) { - int bytes_to_copy = min_t(int, bvec->bv_len - offset, + while (copied_bytes < req_length && + iter.idx < bio->bi_vcnt) { + bvec = bio_iter_all_peek(bio, &iter); + + bytes_to_copy = min_t(int, bvec.bv_len, PAGE_SIZE - actor_offset); bytes_to_copy = min_t(int, bytes_to_copy, req_length - copied_bytes); if (!IS_ERR(actor_addr)) - memcpy(actor_addr + actor_offset, bvec_virt(bvec) + - offset, bytes_to_copy); + memcpy(actor_addr + actor_offset, bvec_virt(&bvec), + bytes_to_copy); actor_offset += bytes_to_copy; copied_bytes += bytes_to_copy; - offset += bytes_to_copy; if (actor_offset >= PAGE_SIZE) { actor_addr = squashfs_next_page(actor); @@ -66,11 +69,8 @@ static int copy_bio_to_actor(struct bio *bio, break; actor_offset = 0; } - if (offset >= bvec->bv_len) { - if (!bio_next_segment(bio, &iter_all)) - break; - offset = 0; - } + + bio_iter_all_advance(bio, &iter, bytes_to_copy); } squashfs_finish_page(actor); return copied_bytes; @@ -85,12 +85,12 @@ static int squashfs_bio_read_cached(struct bio *fullbio, int start_idx = 0, end_idx = 0; struct bvec_iter_all iter_all; struct bio *bio = NULL; - struct bio_vec *bv; + struct bio_vec bv; int idx = 0; int err = 0; bio_for_each_segment_all(bv, fullbio, iter_all) { - struct page *page = bv->bv_page; + struct page *page = bv.bv_page; if (page->mapping == cache_mapping) { idx++; @@ -282,8 +282,10 @@ int squashfs_read_data(struct super_block *sb, u64 index, int length, * Metadata block. */ const u8 *data; - struct bvec_iter_all iter_all = {}; - struct bio_vec *bvec = bvec_init_iter_all(&iter_all); + struct bvec_iter_all iter; + struct bio_vec bvec; + + bvec_iter_all_init(&iter); if (index + 2 > msblk->bytes_used) { res = -EIO; @@ -293,21 +295,25 @@ int squashfs_read_data(struct super_block *sb, u64 index, int length, if (res) goto out; - if (WARN_ON_ONCE(!bio_next_segment(bio, &iter_all))) { + bvec = bio_iter_all_peek(bio, &iter); + + if (WARN_ON_ONCE(!bvec.bv_len)) { res = -EIO; goto out_free_bio; } /* Extract the length of the metadata block */ - data = bvec_virt(bvec); + data = bvec_virt(&bvec); length = data[offset]; - if (offset < bvec->bv_len - 1) { + if (offset < bvec.bv_len - 1) { length |= data[offset + 1] << 8; } else { - if (WARN_ON_ONCE(!bio_next_segment(bio, &iter_all))) { + bio_iter_all_advance(bio, &iter, bvec.bv_len); + + if (WARN_ON_ONCE(!bvec.bv_len)) { res = -EIO; goto out_free_bio; } - data = bvec_virt(bvec); + data = bvec_virt(&bvec); length |= data[0] << 8; } bio_free_pages(bio); diff --git a/fs/squashfs/lz4_wrapper.c b/fs/squashfs/lz4_wrapper.c index 49797729f143..bd0dd787d213 100644 --- a/fs/squashfs/lz4_wrapper.c +++ b/fs/squashfs/lz4_wrapper.c @@ -92,20 +92,23 @@ static int lz4_uncompress(struct squashfs_sb_info *msblk, void *strm, struct bio *bio, int offset, int length, struct squashfs_page_actor *output) { - struct bvec_iter_all iter_all = {}; - struct bio_vec *bvec = bvec_init_iter_all(&iter_all); + struct bvec_iter_all iter; + struct bio_vec bvec; struct squashfs_lz4 *stream = strm; void *buff = stream->input, *data; int bytes = length, res; - while (bio_next_segment(bio, &iter_all)) { - int avail = min(bytes, ((int)bvec->bv_len) - offset); + bvec_iter_all_init(&iter); + bio_iter_all_advance(bio, &iter, offset); - data = bvec_virt(bvec); - memcpy(buff, data + offset, avail); + bio_for_each_segment_all_continue(bvec, bio, iter) { + unsigned avail = min_t(unsigned, bytes, bvec.bv_len); + + memcpy(buff, bvec_virt(&bvec), avail); buff += avail; bytes -= avail; - offset = 0; + if (!bytes) + break; } res = LZ4_decompress_safe(stream->input, stream->output, diff --git a/fs/squashfs/lzo_wrapper.c b/fs/squashfs/lzo_wrapper.c index d216aeefa865..bccfcfa12e63 100644 --- a/fs/squashfs/lzo_wrapper.c +++ b/fs/squashfs/lzo_wrapper.c @@ -66,21 +66,24 @@ static int lzo_uncompress(struct squashfs_sb_info *msblk, void *strm, struct bio *bio, int offset, int length, struct squashfs_page_actor *output) { - struct bvec_iter_all iter_all = {}; - struct bio_vec *bvec = bvec_init_iter_all(&iter_all); + struct bvec_iter_all iter; + struct bio_vec bvec; struct squashfs_lzo *stream = strm; void *buff = stream->input, *data; int bytes = length, res; size_t out_len = output->length; - while (bio_next_segment(bio, &iter_all)) { - int avail = min(bytes, ((int)bvec->bv_len) - offset); + bvec_iter_all_init(&iter); + bio_iter_all_advance(bio, &iter, offset); - data = bvec_virt(bvec); - memcpy(buff, data + offset, avail); + bio_for_each_segment_all_continue(bvec, bio, iter) { + unsigned avail = min_t(unsigned, bytes, bvec.bv_len); + + memcpy(buff, bvec_virt(&bvec), avail); buff += avail; bytes -= avail; - offset = 0; + if (!bytes) + break; } res = lzo1x_decompress_safe(stream->input, (size_t)length, diff --git a/fs/squashfs/xz_wrapper.c b/fs/squashfs/xz_wrapper.c index 6c49481a2f8c..6cf0e11e3b86 100644 --- a/fs/squashfs/xz_wrapper.c +++ b/fs/squashfs/xz_wrapper.c @@ -120,8 +120,7 @@ static int squashfs_xz_uncompress(struct squashfs_sb_info *msblk, void *strm, struct bio *bio, int offset, int length, struct squashfs_page_actor *output) { - struct bvec_iter_all iter_all = {}; - struct bio_vec *bvec = bvec_init_iter_all(&iter_all); + struct bvec_iter_all iter; int total = 0, error = 0; struct squashfs_xz *stream = strm; @@ -136,26 +135,28 @@ static int squashfs_xz_uncompress(struct squashfs_sb_info *msblk, void *strm, goto finish; } + bvec_iter_all_init(&iter); + bio_iter_all_advance(bio, &iter, offset); + for (;;) { enum xz_ret xz_err; if (stream->buf.in_pos == stream->buf.in_size) { - const void *data; - int avail; + struct bio_vec bvec = bio_iter_all_peek(bio, &iter); + unsigned avail = min_t(unsigned, length, bvec.bv_len); - if (!bio_next_segment(bio, &iter_all)) { + if (iter.idx >= bio->bi_vcnt) { /* XZ_STREAM_END must be reached. */ error = -EIO; break; } - avail = min(length, ((int)bvec->bv_len) - offset); - data = bvec_virt(bvec); length -= avail; - stream->buf.in = data + offset; + stream->buf.in = bvec_virt(&bvec); stream->buf.in_size = avail; stream->buf.in_pos = 0; - offset = 0; + + bio_iter_all_advance(bio, &iter, avail); } if (stream->buf.out_pos == stream->buf.out_size) { diff --git a/fs/squashfs/zlib_wrapper.c b/fs/squashfs/zlib_wrapper.c index cbb7afe7bc46..981ca5e41050 100644 --- a/fs/squashfs/zlib_wrapper.c +++ b/fs/squashfs/zlib_wrapper.c @@ -53,8 +53,7 @@ static int zlib_uncompress(struct squashfs_sb_info *msblk, void *strm, struct bio *bio, int offset, int length, struct squashfs_page_actor *output) { - struct bvec_iter_all iter_all = {}; - struct bio_vec *bvec = bvec_init_iter_all(&iter_all); + struct bvec_iter_all iter; int zlib_init = 0, error = 0; z_stream *stream = strm; @@ -67,25 +66,28 @@ static int zlib_uncompress(struct squashfs_sb_info *msblk, void *strm, goto finish; } + bvec_iter_all_init(&iter); + bio_iter_all_advance(bio, &iter, offset); + for (;;) { int zlib_err; if (stream->avail_in == 0) { - const void *data; + struct bio_vec bvec = bio_iter_all_peek(bio, &iter); int avail; - if (!bio_next_segment(bio, &iter_all)) { + if (iter.idx >= bio->bi_vcnt) { /* Z_STREAM_END must be reached. */ error = -EIO; break; } - avail = min(length, ((int)bvec->bv_len) - offset); - data = bvec_virt(bvec); + avail = min_t(unsigned, length, bvec.bv_len); length -= avail; - stream->next_in = data + offset; + stream->next_in = bvec_virt(&bvec); stream->avail_in = avail; - offset = 0; + + bio_iter_all_advance(bio, &iter, avail); } if (stream->avail_out == 0) { diff --git a/fs/squashfs/zstd_wrapper.c b/fs/squashfs/zstd_wrapper.c index 0e407c4d8b3b..658e5d462afa 100644 --- a/fs/squashfs/zstd_wrapper.c +++ b/fs/squashfs/zstd_wrapper.c @@ -68,8 +68,7 @@ static int zstd_uncompress(struct squashfs_sb_info *msblk, void *strm, int error = 0; zstd_in_buffer in_buf = { NULL, 0, 0 }; zstd_out_buffer out_buf = { NULL, 0, 0 }; - struct bvec_iter_all iter_all = {}; - struct bio_vec *bvec = bvec_init_iter_all(&iter_all); + struct bvec_iter_all iter; stream = zstd_init_dstream(wksp->window_size, wksp->mem, wksp->mem_size); @@ -85,25 +84,27 @@ static int zstd_uncompress(struct squashfs_sb_info *msblk, void *strm, goto finish; } + bvec_iter_all_init(&iter); + bio_iter_all_advance(bio, &iter, offset); + for (;;) { size_t zstd_err; if (in_buf.pos == in_buf.size) { - const void *data; - int avail; + struct bio_vec bvec = bio_iter_all_peek(bio, &iter); + unsigned avail = min_t(unsigned, length, bvec.bv_len); - if (!bio_next_segment(bio, &iter_all)) { + if (iter.idx >= bio->bi_vcnt) { error = -EIO; break; } - avail = min(length, ((int)bvec->bv_len) - offset); - data = bvec_virt(bvec); length -= avail; - in_buf.src = data + offset; + in_buf.src = bvec_virt(&bvec); in_buf.size = avail; in_buf.pos = 0; - offset = 0; + + bio_iter_all_advance(bio, &iter, avail); } if (out_buf.pos == out_buf.size) { diff --git a/include/linux/bio.h b/include/linux/bio.h index 41d417ee1349..a251859f1b66 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -78,22 +78,40 @@ static inline void *bio_data(struct bio *bio) return NULL; } -static inline bool bio_next_segment(const struct bio *bio, - struct bvec_iter_all *iter) +static inline struct bio_vec bio_iter_all_peek(const struct bio *bio, + struct bvec_iter_all *iter) { - if (iter->idx >= bio->bi_vcnt) - return false; + if (WARN_ON(iter->idx >= bio->bi_vcnt)) + return (struct bio_vec) { NULL }; - bvec_advance(&bio->bi_io_vec[iter->idx], iter); - return true; + return bvec_iter_all_peek(bio->bi_io_vec, iter); +} + +static inline void bio_iter_all_advance(const struct bio *bio, + struct bvec_iter_all *iter, + unsigned bytes) +{ + bvec_iter_all_advance(bio->bi_io_vec, iter, bytes); + + WARN_ON(iter->idx > bio->bi_vcnt || + (iter->idx == bio->bi_vcnt && iter->done)); } +#define bio_for_each_segment_all_continue(bvl, bio, iter) \ + for (; \ + iter.idx < bio->bi_vcnt && \ + ((bvl = bio_iter_all_peek(bio, &iter)), true); \ + bio_iter_all_advance((bio), &iter, bvl.bv_len)) + /* * drivers should _never_ use the all version - the bio may have been split * before it got to the driver and the driver won't own all of it */ -#define bio_for_each_segment_all(bvl, bio, iter) \ - for (bvl = bvec_init_iter_all(&iter); bio_next_segment((bio), &iter); ) +#define bio_for_each_segment_all(bvl, bio, iter) \ + for (bvec_iter_all_init(&iter); \ + iter.idx < (bio)->bi_vcnt && \ + ((bvl = bio_iter_all_peek((bio), &iter)), true); \ + bio_iter_all_advance((bio), &iter, bvl.bv_len)) static inline void bio_advance_iter(const struct bio *bio, struct bvec_iter *iter, unsigned int bytes) diff --git a/include/linux/bvec.h b/include/linux/bvec.h index 555aae5448ae..635fb5414321 100644 --- a/include/linux/bvec.h +++ b/include/linux/bvec.h @@ -85,12 +85,6 @@ struct bvec_iter { current bvec */ } __packed; -struct bvec_iter_all { - struct bio_vec bv; - int idx; - unsigned done; -}; - /* * various member access, note that bio_data should of course not be used * on highmem page vectors @@ -184,7 +178,10 @@ static inline void bvec_iter_advance_single(const struct bio_vec *bv, ((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \ bvec_iter_advance_single((bio_vec), &(iter), (bvl).bv_len)) -/* for iterating one bio from start to end */ +/* + * bvec_iter_all: for advancing over a bio as it was originally created, but + * with the usual bio_for_each_segment interface - nonstandard, do not use: + */ #define BVEC_ITER_ALL_INIT (struct bvec_iter) \ { \ .bi_sector = 0, \ @@ -193,33 +190,45 @@ static inline void bvec_iter_advance_single(const struct bio_vec *bv, .bi_bvec_done = 0, \ } -static inline struct bio_vec *bvec_init_iter_all(struct bvec_iter_all *iter_all) +/* + * bvec_iter_all: for advancing over individual pages in a bio, as it was when + * it was first created: + */ +struct bvec_iter_all { + int idx; + unsigned done; +}; + +static inline void bvec_iter_all_init(struct bvec_iter_all *iter_all) { iter_all->done = 0; iter_all->idx = 0; +} - return &iter_all->bv; +static inline struct bio_vec bvec_iter_all_peek(const struct bio_vec *bvec, + struct bvec_iter_all *iter) +{ + struct bio_vec bv = bvec[iter->idx]; + + bv.bv_offset += iter->done; + bv.bv_len -= iter->done; + + bv.bv_page += bv.bv_offset >> PAGE_SHIFT; + bv.bv_offset &= ~PAGE_MASK; + bv.bv_len = min_t(unsigned, PAGE_SIZE - bv.bv_offset, bv.bv_len); + + return bv; } -static inline void bvec_advance(const struct bio_vec *bvec, - struct bvec_iter_all *iter_all) +static inline void bvec_iter_all_advance(const struct bio_vec *bvec, + struct bvec_iter_all *iter, + unsigned bytes) { - struct bio_vec *bv = &iter_all->bv; - - if (iter_all->done) { - bv->bv_page++; - bv->bv_offset = 0; - } else { - bv->bv_page = bvec->bv_page + (bvec->bv_offset >> PAGE_SHIFT); - bv->bv_offset = bvec->bv_offset & ~PAGE_MASK; - } - bv->bv_len = min_t(unsigned int, PAGE_SIZE - bv->bv_offset, - bvec->bv_len - iter_all->done); - iter_all->done += bv->bv_len; + iter->done += bytes; - if (iter_all->done == bvec->bv_len) { - iter_all->idx++; - iter_all->done = 0; + while (iter->done && iter->done >= bvec[iter->idx].bv_len) { + iter->done -= bvec[iter->idx].bv_len; + iter->idx++; } } From patchwork Wed Nov 22 23:28:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kent Overstreet X-Patchwork-Id: 13465568 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="qVPKJqdS" Received: from out-187.mta0.migadu.com (out-187.mta0.migadu.com [91.218.175.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F2DAD1A8 for ; Wed, 22 Nov 2023 15:28:27 -0800 (PST) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1700695706; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=nSlVHS2FqUDkgyXo8OaH+PY2FOlXv5QWatX7YM/6Q4M=; b=qVPKJqdStYw4Ss1jbKZes2vyG4pZXgI2lNLp7xNrCUpaVC3bpHsBTZjODf1wvrLTNnYJqi GHcrE6OfVJKnD4Qcpkpi7BRDCr9g4N1WJf2LY1YWyIFDmDBHPJIMVzA+mzlMQJfe1wljoU 5fNiK3w8CIm0gE4PhQUakpFdQGSuv18= From: Kent Overstreet To: axboe@kernel.dk, linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org Cc: Kent Overstreet , Matthew Wilcox Subject: [PATCH 2/3] block: Rework bio_for_each_folio_all(), add bio_for_each_folio() Date: Wed, 22 Nov 2023 18:28:14 -0500 Message-ID: <20231122232818.178256-2-kent.overstreet@linux.dev> In-Reply-To: <20231122232818.178256-1-kent.overstreet@linux.dev> References: <20231122232818.178256-1-kent.overstreet@linux.dev> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT This reimplements bio_for_each_folio_all() on top of the newly-reworked bvec_iter_all, and adds a new common helper biovec_to_foliovec() for both bio_for_each_folio_all() and bio_for_each_folio(). This allows bcachefs's private bio_for_each_folio() to be dropped. Cc: Matthew Wilcox Cc: linux-block@vger.kernel.org Signed-off-by: Kent Overstreet Acked-by: Eric Biggers --- drivers/md/dm-crypt.c | 13 +++--- drivers/md/dm-flakey.c | 7 +-- fs/bcachefs/fs-io-buffered.c | 38 ++++++++------- fs/bcachefs/fs-io.h | 43 ----------------- fs/crypto/bio.c | 9 ++-- fs/ext4/page-io.c | 11 +++-- fs/ext4/readpage.c | 7 +-- fs/iomap/buffered-io.c | 14 +++--- fs/mpage.c | 22 +++++---- fs/verity/verify.c | 7 +-- include/linux/bio.h | 91 ++++++++++++++++++------------------ include/linux/bvec.h | 15 ++++-- 12 files changed, 127 insertions(+), 150 deletions(-) diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index 2ae8560b6a14..adc130e158cd 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -1737,16 +1737,17 @@ static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned int size) static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) { - struct folio_iter fi; + struct bvec_iter_all iter; + struct folio_vec fv; if (clone->bi_vcnt > 0) { /* bio_for_each_folio_all crashes with an empty bio */ - bio_for_each_folio_all(fi, clone) { - if (folio_test_large(fi.folio)) { + bio_for_each_folio_all(fv, clone, iter) { + if (folio_test_large(fv.fv_folio)) { percpu_counter_sub(&cc->n_allocated_pages, - 1 << folio_order(fi.folio)); - folio_put(fi.folio); + 1 << folio_order(fv.fv_folio)); + folio_put(fv.fv_folio); } else { - mempool_free(&fi.folio->page, &cc->page_pool); + mempool_free(&fv.fv_folio->page, &cc->page_pool); } } } diff --git a/drivers/md/dm-flakey.c b/drivers/md/dm-flakey.c index 120153e44ae0..906cb2c66945 100644 --- a/drivers/md/dm-flakey.c +++ b/drivers/md/dm-flakey.c @@ -391,11 +391,12 @@ static void corrupt_bio_random(struct bio *bio) static void clone_free(struct bio *clone) { - struct folio_iter fi; + struct bvec_iter_all iter; + struct folio_vec fv; if (clone->bi_vcnt > 0) { /* bio_for_each_folio_all crashes with an empty bio */ - bio_for_each_folio_all(fi, clone) - folio_put(fi.folio); + bio_for_each_folio_all(fv, clone, iter) + folio_put(fv.fv_folio); } bio_uninit(clone); diff --git a/fs/bcachefs/fs-io-buffered.c b/fs/bcachefs/fs-io-buffered.c index 52f0e7acda3d..021308492766 100644 --- a/fs/bcachefs/fs-io-buffered.c +++ b/fs/bcachefs/fs-io-buffered.c @@ -28,16 +28,17 @@ static inline bool bio_full(struct bio *bio, unsigned len) static void bch2_readpages_end_io(struct bio *bio) { - struct folio_iter fi; + struct bvec_iter_all iter; + struct folio_vec fv; - bio_for_each_folio_all(fi, bio) { + bio_for_each_folio_all(fv, bio, iter) { if (!bio->bi_status) { - folio_mark_uptodate(fi.folio); + folio_mark_uptodate(fv.fv_folio); } else { - folio_clear_uptodate(fi.folio); - folio_set_error(fi.folio); + folio_clear_uptodate(fv.fv_folio); + folio_set_error(fv.fv_folio); } - folio_unlock(fi.folio); + folio_unlock(fv.fv_folio); } bio_put(bio); @@ -410,33 +411,34 @@ static void bch2_writepage_io_done(struct bch_write_op *op) container_of(op, struct bch_writepage_io, op); struct bch_fs *c = io->op.c; struct bio *bio = &io->op.wbio.bio; - struct folio_iter fi; + struct bvec_iter_all iter; + struct folio_vec fv; unsigned i; if (io->op.error) { set_bit(EI_INODE_ERROR, &io->inode->ei_flags); - bio_for_each_folio_all(fi, bio) { + bio_for_each_folio_all(fv, bio, iter) { struct bch_folio *s; - folio_set_error(fi.folio); - mapping_set_error(fi.folio->mapping, -EIO); + folio_set_error(fv.fv_folio); + mapping_set_error(fv.fv_folio->mapping, -EIO); - s = __bch2_folio(fi.folio); + s = __bch2_folio(fv.fv_folio); spin_lock(&s->lock); - for (i = 0; i < folio_sectors(fi.folio); i++) + for (i = 0; i < folio_sectors(fv.fv_folio); i++) s->s[i].nr_replicas = 0; spin_unlock(&s->lock); } } if (io->op.flags & BCH_WRITE_WROTE_DATA_INLINE) { - bio_for_each_folio_all(fi, bio) { + bio_for_each_folio_all(fv, bio, iter) { struct bch_folio *s; - s = __bch2_folio(fi.folio); + s = __bch2_folio(fv.fv_folio); spin_lock(&s->lock); - for (i = 0; i < folio_sectors(fi.folio); i++) + for (i = 0; i < folio_sectors(fv.fv_folio); i++) s->s[i].nr_replicas = 0; spin_unlock(&s->lock); } @@ -461,11 +463,11 @@ static void bch2_writepage_io_done(struct bch_write_op *op) */ bch2_i_sectors_acct(c, io->inode, NULL, io->op.i_sectors_delta); - bio_for_each_folio_all(fi, bio) { - struct bch_folio *s = __bch2_folio(fi.folio); + bio_for_each_folio_all(fv, bio, iter) { + struct bch_folio *s = __bch2_folio(fv.fv_folio); if (atomic_dec_and_test(&s->write_count)) - folio_end_writeback(fi.folio); + folio_end_writeback(fv.fv_folio); } bio_put(&io->op.wbio.bio); diff --git a/fs/bcachefs/fs-io.h b/fs/bcachefs/fs-io.h index ca70346e68dc..8c618b3df8dc 100644 --- a/fs/bcachefs/fs-io.h +++ b/fs/bcachefs/fs-io.h @@ -11,49 +11,6 @@ #include -struct folio_vec { - struct folio *fv_folio; - size_t fv_offset; - size_t fv_len; -}; - -static inline struct folio_vec biovec_to_foliovec(struct bio_vec bv) -{ - - struct folio *folio = page_folio(bv.bv_page); - size_t offset = (folio_page_idx(folio, bv.bv_page) << PAGE_SHIFT) + - bv.bv_offset; - size_t len = min_t(size_t, folio_size(folio) - offset, bv.bv_len); - - return (struct folio_vec) { - .fv_folio = folio, - .fv_offset = offset, - .fv_len = len, - }; -} - -static inline struct folio_vec bio_iter_iovec_folio(struct bio *bio, - struct bvec_iter iter) -{ - return biovec_to_foliovec(bio_iter_iovec(bio, iter)); -} - -#define __bio_for_each_folio(bvl, bio, iter, start) \ - for (iter = (start); \ - (iter).bi_size && \ - ((bvl = bio_iter_iovec_folio((bio), (iter))), 1); \ - bio_advance_iter_single((bio), &(iter), (bvl).fv_len)) - -/** - * bio_for_each_folio - iterate over folios within a bio - * - * Like other non-_all versions, this iterates over what bio->bi_iter currently - * points to. This version is for drivers, where the bio may have previously - * been split or cloned. - */ -#define bio_for_each_folio(bvl, bio, iter) \ - __bio_for_each_folio(bvl, bio, iter, (bio)->bi_iter) - struct quota_res { u64 sectors; }; diff --git a/fs/crypto/bio.c b/fs/crypto/bio.c index 0ad8c30b8fa5..5cfc146c68b6 100644 --- a/fs/crypto/bio.c +++ b/fs/crypto/bio.c @@ -30,11 +30,12 @@ */ bool fscrypt_decrypt_bio(struct bio *bio) { - struct folio_iter fi; + struct bvec_iter_all iter; + struct folio_vec fv; - bio_for_each_folio_all(fi, bio) { - int err = fscrypt_decrypt_pagecache_blocks(fi.folio, fi.length, - fi.offset); + bio_for_each_folio_all(fv, bio, iter) { + int err = fscrypt_decrypt_pagecache_blocks(fv.fv_folio, fv.fv_len, + fv.fv_offset); if (err) { bio->bi_status = errno_to_blk_status(err); diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c index dfdd7e5cf038..c5938b3e8825 100644 --- a/fs/ext4/page-io.c +++ b/fs/ext4/page-io.c @@ -99,14 +99,15 @@ static void buffer_io_error(struct buffer_head *bh) static void ext4_finish_bio(struct bio *bio) { - struct folio_iter fi; + struct bvec_iter_all iter; + struct folio_vec fv; - bio_for_each_folio_all(fi, bio) { - struct folio *folio = fi.folio; + bio_for_each_folio_all(fv, bio, iter) { + struct folio *folio = fv.fv_folio; struct folio *io_folio = NULL; struct buffer_head *bh, *head; - size_t bio_start = fi.offset; - size_t bio_end = bio_start + fi.length; + size_t bio_start = fv.fv_offset; + size_t bio_end = bio_start + fv.fv_len; unsigned under_io = 0; unsigned long flags; diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c index 21e8f0aebb3c..14b67ba01fbe 100644 --- a/fs/ext4/readpage.c +++ b/fs/ext4/readpage.c @@ -68,10 +68,11 @@ struct bio_post_read_ctx { static void __read_end_io(struct bio *bio) { - struct folio_iter fi; + struct bvec_iter_all iter; + struct folio_vec fv; - bio_for_each_folio_all(fi, bio) - folio_end_read(fi.folio, bio->bi_status == 0); + bio_for_each_folio_all(fv, bio, iter) + folio_end_read(fv.fv_folio, bio->bi_status == 0); if (bio->bi_private) mempool_free(bio->bi_private, bio_post_read_ctx_pool); bio_put(bio); diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 3356df4d8fb9..83615117ece2 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -277,10 +277,11 @@ static void iomap_finish_folio_read(struct folio *folio, size_t off, static void iomap_read_end_io(struct bio *bio) { int error = blk_status_to_errno(bio->bi_status); - struct folio_iter fi; + struct bvec_iter_all iter; + struct folio_vec fv; - bio_for_each_folio_all(fi, bio) - iomap_finish_folio_read(fi.folio, fi.offset, fi.length, error); + bio_for_each_folio_all(fv, bio, iter) + iomap_finish_folio_read(fv.fv_folio, fv.fv_offset, fv.fv_len, error); bio_put(bio); } @@ -1514,7 +1515,8 @@ iomap_finish_ioend(struct iomap_ioend *ioend, int error) u32 folio_count = 0; for (bio = &ioend->io_inline_bio; bio; bio = next) { - struct folio_iter fi; + struct bvec_iter_all iter; + struct folio_vec fv; /* * For the last bio, bi_private points to the ioend, so we @@ -1526,8 +1528,8 @@ iomap_finish_ioend(struct iomap_ioend *ioend, int error) next = bio->bi_private; /* walk all folios in bio, ending page IO on them */ - bio_for_each_folio_all(fi, bio) { - iomap_finish_folio_write(inode, fi.folio, fi.length, + bio_for_each_folio_all(fv, bio, iter) { + iomap_finish_folio_write(inode, fv.fv_folio, fv.fv_len, error); folio_count++; } diff --git a/fs/mpage.c b/fs/mpage.c index ffb064ed9d04..0196edf9a684 100644 --- a/fs/mpage.c +++ b/fs/mpage.c @@ -45,15 +45,16 @@ */ static void mpage_read_end_io(struct bio *bio) { - struct folio_iter fi; + struct bvec_iter_all iter; + struct folio_vec fv; int err = blk_status_to_errno(bio->bi_status); - bio_for_each_folio_all(fi, bio) { + bio_for_each_folio_all(fv, bio, iter) { if (err) - folio_set_error(fi.folio); + folio_set_error(fv.fv_folio); else - folio_mark_uptodate(fi.folio); - folio_unlock(fi.folio); + folio_mark_uptodate(fv.fv_folio); + folio_unlock(fv.fv_folio); } bio_put(bio); @@ -61,15 +62,16 @@ static void mpage_read_end_io(struct bio *bio) static void mpage_write_end_io(struct bio *bio) { - struct folio_iter fi; + struct bvec_iter_all iter; + struct folio_vec fv; int err = blk_status_to_errno(bio->bi_status); - bio_for_each_folio_all(fi, bio) { + bio_for_each_folio_all(fv, bio, iter) { if (err) { - folio_set_error(fi.folio); - mapping_set_error(fi.folio->mapping, err); + folio_set_error(fv.fv_folio); + mapping_set_error(fv.fv_folio->mapping, err); } - folio_end_writeback(fi.folio); + folio_end_writeback(fv.fv_folio); } bio_put(bio); diff --git a/fs/verity/verify.c b/fs/verity/verify.c index 904ccd7e8e16..8d444b1c546d 100644 --- a/fs/verity/verify.c +++ b/fs/verity/verify.c @@ -307,7 +307,8 @@ EXPORT_SYMBOL_GPL(fsverity_verify_blocks); */ void fsverity_verify_bio(struct bio *bio) { - struct folio_iter fi; + struct bvec_iter_all iter; + struct folio_vec fv; unsigned long max_ra_pages = 0; if (bio->bi_opf & REQ_RAHEAD) { @@ -323,8 +324,8 @@ void fsverity_verify_bio(struct bio *bio) max_ra_pages = bio->bi_iter.bi_size >> (PAGE_SHIFT + 2); } - bio_for_each_folio_all(fi, bio) { - if (!verify_data_blocks(fi.folio, fi.length, fi.offset, + bio_for_each_folio_all(fv, bio, iter) { + if (!verify_data_blocks(fv.fv_folio, fv.fv_len, fv.fv_offset, max_ra_pages)) { bio->bi_status = BLK_STS_IOERR; break; diff --git a/include/linux/bio.h b/include/linux/bio.h index a251859f1b66..eaaf7e5f0d54 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -169,6 +169,42 @@ static inline void bio_advance(struct bio *bio, unsigned int nbytes) #define bio_for_each_segment(bvl, bio, iter) \ __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter) +struct folio_vec { + struct folio *fv_folio; + size_t fv_offset; + size_t fv_len; +}; + +static inline struct folio_vec biovec_to_foliovec(struct bio_vec bv) +{ + + struct folio *folio = page_folio(bv.bv_page); + size_t offset = (folio_page_idx(folio, bv.bv_page) << PAGE_SHIFT) + + bv.bv_offset; + size_t len = min_t(size_t, folio_size(folio) - offset, bv.bv_len); + + return (struct folio_vec) { + .fv_folio = folio, + .fv_offset = offset, + .fv_len = len, + }; +} + +static inline struct folio_vec bio_iter_iovec_folio(struct bio *bio, + struct bvec_iter iter) +{ + return biovec_to_foliovec(bio_iter_iovec(bio, iter)); +} + +#define __bio_for_each_folio(bvl, bio, iter, start) \ + for (iter = (start); \ + (iter).bi_size && \ + ((bvl = bio_iter_iovec_folio((bio), (iter))), 1); \ + bio_advance_iter_single((bio), &(iter), (bvl).fv_len)) + +#define bio_for_each_folio(bvl, bio, iter) \ + __bio_for_each_folio(bvl, bio, iter, (bio)->bi_iter) + #define __bio_for_each_bvec(bvl, bio, iter, start) \ for (iter = (start); \ (iter).bi_size && \ @@ -282,59 +318,22 @@ static inline struct bio_vec *bio_last_bvec_all(struct bio *bio) return &bio->bi_io_vec[bio->bi_vcnt - 1]; } -/** - * struct folio_iter - State for iterating all folios in a bio. - * @folio: The current folio we're iterating. NULL after the last folio. - * @offset: The byte offset within the current folio. - * @length: The number of bytes in this iteration (will not cross folio - * boundary). - */ -struct folio_iter { - struct folio *folio; - size_t offset; - size_t length; - /* private: for use by the iterator */ - struct folio *_next; - size_t _seg_count; - int _i; -}; - -static inline void bio_first_folio(struct folio_iter *fi, struct bio *bio, - int i) -{ - struct bio_vec *bvec = bio_first_bvec_all(bio) + i; - - fi->folio = page_folio(bvec->bv_page); - fi->offset = bvec->bv_offset + - PAGE_SIZE * (bvec->bv_page - &fi->folio->page); - fi->_seg_count = bvec->bv_len; - fi->length = min(folio_size(fi->folio) - fi->offset, fi->_seg_count); - fi->_next = folio_next(fi->folio); - fi->_i = i; -} - -static inline void bio_next_folio(struct folio_iter *fi, struct bio *bio) +static inline struct folio_vec bio_folio_iter_all_peek(const struct bio *bio, + const struct bvec_iter_all *iter) { - fi->_seg_count -= fi->length; - if (fi->_seg_count) { - fi->folio = fi->_next; - fi->offset = 0; - fi->length = min(folio_size(fi->folio), fi->_seg_count); - fi->_next = folio_next(fi->folio); - } else if (fi->_i + 1 < bio->bi_vcnt) { - bio_first_folio(fi, bio, fi->_i + 1); - } else { - fi->folio = NULL; - } + return biovec_to_foliovec(__bvec_iter_all_peek(bio->bi_io_vec, iter)); } /** * bio_for_each_folio_all - Iterate over each folio in a bio. - * @fi: struct folio_iter which is updated for each folio. + * @fi: struct bio_folio_iter_all which is updated for each folio. * @bio: struct bio to iterate over. */ -#define bio_for_each_folio_all(fi, bio) \ - for (bio_first_folio(&fi, bio, 0); fi.folio; bio_next_folio(&fi, bio)) +#define bio_for_each_folio_all(fv, bio, iter) \ + for (bvec_iter_all_init(&iter); \ + iter.idx < bio->bi_vcnt && \ + ((fv = bio_folio_iter_all_peek(bio, &iter)), true); \ + bio_iter_all_advance((bio), &iter, fv.fv_len)) enum bip_flags { BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */ diff --git a/include/linux/bvec.h b/include/linux/bvec.h index 635fb5414321..d238f959e36c 100644 --- a/include/linux/bvec.h +++ b/include/linux/bvec.h @@ -205,18 +205,27 @@ static inline void bvec_iter_all_init(struct bvec_iter_all *iter_all) iter_all->idx = 0; } -static inline struct bio_vec bvec_iter_all_peek(const struct bio_vec *bvec, - struct bvec_iter_all *iter) +static inline struct bio_vec __bvec_iter_all_peek(const struct bio_vec *bvec, + const struct bvec_iter_all *iter) { struct bio_vec bv = bvec[iter->idx]; + BUG_ON(iter->done >= bv.bv_len); + bv.bv_offset += iter->done; bv.bv_len -= iter->done; bv.bv_page += bv.bv_offset >> PAGE_SHIFT; bv.bv_offset &= ~PAGE_MASK; - bv.bv_len = min_t(unsigned, PAGE_SIZE - bv.bv_offset, bv.bv_len); + return bv; +} + +static inline struct bio_vec bvec_iter_all_peek(const struct bio_vec *bvec, + const struct bvec_iter_all *iter) +{ + struct bio_vec bv = __bvec_iter_all_peek(bvec, iter); + bv.bv_len = min_t(unsigned, PAGE_SIZE - bv.bv_offset, bv.bv_len); return bv; } From patchwork Wed Nov 22 23:28:15 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kent Overstreet X-Patchwork-Id: 13465569 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="q8FMhX4D" Received: from out-187.mta0.migadu.com (out-187.mta0.migadu.com [91.218.175.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5F854110 for ; Wed, 22 Nov 2023 15:28:28 -0800 (PST) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1700695706; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=wdxKnJ2FmIDaRAshfSUcmrGs+dMUGZeUTYVCPDJSnpk=; b=q8FMhX4D68JVMtBwOlZC8K7WTFcuV7dFt6Tdp+yJPOCFEpENVPE1X/9EsC7aj4rSAKviNs YXezFsQOaw4edYpaUeU3NRGO/ewnZZTbyesH4EgJzwvsM/xIaMGMlYZkbPYW7OSL+/FYyJ ghl5q/SL7SVDzkrhNFrysTuy3zB75cs= From: Kent Overstreet To: axboe@kernel.dk, linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org Cc: Kent Overstreet , Ming Lei Subject: [PATCH 3/3] block: Add documentation for bio iterator macros Date: Wed, 22 Nov 2023 18:28:15 -0500 Message-ID: <20231122232818.178256-3-kent.overstreet@linux.dev> In-Reply-To: <20231122232818.178256-1-kent.overstreet@linux.dev> References: <20231122232818.178256-1-kent.overstreet@linux.dev> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT We've now got 3x2 interfaces for iterating over bios: by page, by bvec, or by folio, and variants that iterate over what bi_iter points to, or the entire bio as created by the filesystem/originator. This adds more detailed kerneldoc comments for each variant. Signed-off-by: Kent Overstreet Cc: Jens Axboe Cc: Ming Lei Cc: linux-block@vger.kernel.org Reviewed-by: Ming Lei --- include/linux/bio.h | 54 ++++++++++++++++++++++++++++++++++++++++----- 1 file changed, 48 insertions(+), 6 deletions(-) diff --git a/include/linux/bio.h b/include/linux/bio.h index eaaf7e5f0d54..21524a953f6e 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -103,9 +103,14 @@ static inline void bio_iter_all_advance(const struct bio *bio, ((bvl = bio_iter_all_peek(bio, &iter)), true); \ bio_iter_all_advance((bio), &iter, bvl.bv_len)) -/* - * drivers should _never_ use the all version - the bio may have been split - * before it got to the driver and the driver won't own all of it +/** + * bio_for_each_segment_all - iterate over single pages in a bio + * + * Like other _all versions, this is for the filesystem, or the owner/creator of + * a bio; it iterates over the original contents of a bio. + * + * Drivers that are working with bios that were submitted to them should not use + * the _all version. */ #define bio_for_each_segment_all(bvl, bio, iter) \ for (bvec_iter_all_init(&iter); \ @@ -166,6 +171,13 @@ static inline void bio_advance(struct bio *bio, unsigned int nbytes) ((bvl = bio_iter_iovec((bio), (iter))), 1); \ bio_advance_iter_single((bio), &(iter), (bvl).bv_len)) +/** + * bio_for_each_segment - iterate over single pages in a bio + * + * Like other non-_all versions, this iterates over what bio->bi_iter currently + * points to. This version is for drivers, where the bio may have previously + * been split or cloned. + */ #define bio_for_each_segment(bvl, bio, iter) \ __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter) @@ -202,6 +214,13 @@ static inline struct folio_vec bio_iter_iovec_folio(struct bio *bio, ((bvl = bio_iter_iovec_folio((bio), (iter))), 1); \ bio_advance_iter_single((bio), &(iter), (bvl).fv_len)) +/** + * bio_for_each_folio - iterate over folios within a bio + * + * Like other non-_all versions, this iterates over what bio->bi_iter currently + * points to. This version is for drivers, where the bio may have previously + * been split or cloned. + */ #define bio_for_each_folio(bvl, bio, iter) \ __bio_for_each_folio(bvl, bio, iter, (bio)->bi_iter) @@ -211,13 +230,30 @@ static inline struct folio_vec bio_iter_iovec_folio(struct bio *bio, ((bvl = mp_bvec_iter_bvec((bio)->bi_io_vec, (iter))), 1); \ bio_advance_iter_single((bio), &(iter), (bvl).bv_len)) -/* iterate over multi-page bvec */ +/** + * bio_for_each_bvec - iterate over bvecs within a bio + * + * This version iterates over entire bio_vecs, which will be a range of + * contiguous pages. + * + * Like other non-_all versions, this iterates over what bio->bi_iter currently + * points to. This version is for drivers, where the bio may have previously + * been split or cloned. + */ #define bio_for_each_bvec(bvl, bio, iter) \ __bio_for_each_bvec(bvl, bio, iter, (bio)->bi_iter) /* - * Iterate over all multi-page bvecs. Drivers shouldn't use this version for the - * same reasons as bio_for_each_segment_all(). + * bio_for_each_bvec_all - iterate over bvecs within a bio + * + * This version iterates over entire bio_vecs, which will be a range of + * contiguous pages. + * + * Like other _all versions, this is for the filesystem, or the owner/creator of + * a bio; it iterates over the original contents of a bio. + * + * Drivers that are working with bios that were submitted to them should not use + * the _all version. */ #define bio_for_each_bvec_all(bvl, bio, i) \ for (i = 0, bvl = bio_first_bvec_all(bio); \ @@ -328,6 +364,12 @@ static inline struct folio_vec bio_folio_iter_all_peek(const struct bio *bio, * bio_for_each_folio_all - Iterate over each folio in a bio. * @fi: struct bio_folio_iter_all which is updated for each folio. * @bio: struct bio to iterate over. + * + * Like other _all versions, this is for the filesystem, or the owner/creator of + * a bio; it iterates over the original contents of a bio. + * + * Drivers that are working with bios that were submitted to them should not use + * the _all version. */ #define bio_for_each_folio_all(fv, bio, iter) \ for (bvec_iter_all_init(&iter); \