| Message ID | 20250409111055.3640328-8-hch@lst.de (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [1/8] btrfs: remove the alignment checks in end_bbio_data_read | expand |
在 2025/4/9 20:40, Christoph Hellwig 写道: > Add a helper to get the actual kernel address of a stripe instead of > just the page and offset into it to simplify the code, and add another > helper to add the memory backing a sector to a bio using the above > helper. > > This nicely abstracts away the page + offset representation from almost > all of the scrub code. I love this change, and it should also be safe because all scrub pages are allocated by ourselves, and are ensured not to be high mem. Reviewed-by: Qu Wenruo <wqu@suse.com> Thanks, Qu> > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > fs/btrfs/scrub.c | 81 +++++++++++++++--------------------------------- > 1 file changed, 25 insertions(+), 56 deletions(-) > > diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c > index 49021765c17b..d014b728eb0d 100644 > --- a/fs/btrfs/scrub.c > +++ b/fs/btrfs/scrub.c > @@ -579,20 +579,13 @@ static int fill_writer_pointer_gap(struct scrub_ctx *sctx, u64 physical) > return ret; > } > > -static struct page *scrub_stripe_get_page(struct scrub_stripe *stripe, int sector_nr) > +static void *scrub_stripe_get_kaddr(struct scrub_stripe *stripe, int sector_nr) > { > struct btrfs_fs_info *fs_info = stripe->bg->fs_info; > - int page_index = (sector_nr << fs_info->sectorsize_bits) >> PAGE_SHIFT; > + u32 offset = sector_nr << fs_info->sectorsize_bits; > > - return stripe->pages[page_index]; > -} > - > -static unsigned int scrub_stripe_get_page_offset(struct scrub_stripe *stripe, > - int sector_nr) > -{ > - struct btrfs_fs_info *fs_info = stripe->bg->fs_info; > - > - return offset_in_page(sector_nr << fs_info->sectorsize_bits); > + return page_address(stripe->pages[offset >> PAGE_SHIFT]) + > + offset_in_page(offset); > } > > static void scrub_verify_one_metadata(struct scrub_stripe *stripe, int sector_nr) > @@ -600,19 +593,17 @@ static void scrub_verify_one_metadata(struct scrub_stripe *stripe, int sector_nr > struct btrfs_fs_info *fs_info = stripe->bg->fs_info; > const u32 sectors_per_tree = fs_info->nodesize >> fs_info->sectorsize_bits; > const u64 logical = stripe->logical + (sector_nr << fs_info->sectorsize_bits); > - const struct page *first_page = scrub_stripe_get_page(stripe, sector_nr); > - const unsigned int first_off = scrub_stripe_get_page_offset(stripe, sector_nr); > + void *first_kaddr = scrub_stripe_get_kaddr(stripe, sector_nr); > SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); > u8 on_disk_csum[BTRFS_CSUM_SIZE]; > u8 calculated_csum[BTRFS_CSUM_SIZE]; > - struct btrfs_header *header; > + struct btrfs_header *header = first_kaddr; > > /* > * Here we don't have a good way to attach the pages (and subpages) > * to a dummy extent buffer, thus we have to directly grab the members > * from pages. > */ > - header = (struct btrfs_header *)(page_address(first_page) + first_off); > memcpy(on_disk_csum, header->csum, fs_info->csum_size); > > if (logical != btrfs_stack_header_bytenr(header)) { > @@ -648,14 +639,11 @@ static void scrub_verify_one_metadata(struct scrub_stripe *stripe, int sector_nr > /* Now check tree block csum. */ > shash->tfm = fs_info->csum_shash; > crypto_shash_init(shash); > - crypto_shash_update(shash, page_address(first_page) + first_off + > - BTRFS_CSUM_SIZE, fs_info->sectorsize - BTRFS_CSUM_SIZE); > + crypto_shash_update(shash, first_kaddr + BTRFS_CSUM_SIZE, > + fs_info->sectorsize - BTRFS_CSUM_SIZE); > > for (int i = sector_nr + 1; i < sector_nr + sectors_per_tree; i++) { > - struct page *page = scrub_stripe_get_page(stripe, i); > - unsigned int page_off = scrub_stripe_get_page_offset(stripe, i); > - > - crypto_shash_update(shash, page_address(page) + page_off, > + crypto_shash_update(shash, scrub_stripe_get_kaddr(stripe, i), > fs_info->sectorsize); > } > > @@ -691,10 +679,8 @@ static void scrub_verify_one_sector(struct scrub_stripe *stripe, int sector_nr) > struct btrfs_fs_info *fs_info = stripe->bg->fs_info; > struct scrub_sector_verification *sector = &stripe->sectors[sector_nr]; > const u32 sectors_per_tree = fs_info->nodesize >> fs_info->sectorsize_bits; > - struct page *page = scrub_stripe_get_page(stripe, sector_nr); > - unsigned int pgoff = scrub_stripe_get_page_offset(stripe, sector_nr); > + void *kaddr = scrub_stripe_get_kaddr(stripe, sector_nr); > u8 csum_buf[BTRFS_CSUM_SIZE]; > - void *kaddr; > int ret; > > ASSERT(sector_nr >= 0 && sector_nr < stripe->nr_sectors); > @@ -738,9 +724,7 @@ static void scrub_verify_one_sector(struct scrub_stripe *stripe, int sector_nr) > return; > } > > - kaddr = kmap_local_page(page) + pgoff; > ret = btrfs_check_sector_csum(fs_info, kaddr, csum_buf, sector->csum); > - kunmap_local(kaddr); > if (ret < 0) { > set_bit(sector_nr, &stripe->csum_error_bitmap); > set_bit(sector_nr, &stripe->error_bitmap); > @@ -769,8 +753,7 @@ static int calc_sector_number(struct scrub_stripe *stripe, struct bio_vec *first > int i; > > for (i = 0; i < stripe->nr_sectors; i++) { > - if (scrub_stripe_get_page(stripe, i) == first_bvec->bv_page && > - scrub_stripe_get_page_offset(stripe, i) == first_bvec->bv_offset) > + if (scrub_stripe_get_kaddr(stripe, i) == bvec_virt(first_bvec)) > break; > } > ASSERT(i < stripe->nr_sectors); > @@ -817,6 +800,15 @@ static int calc_next_mirror(int mirror, int num_copies) > return (mirror + 1 > num_copies) ? 1 : mirror + 1; > } > > +static void scrub_bio_add_sector(struct btrfs_bio *bbio, > + struct scrub_stripe *stripe, int sector_nr) > +{ > + void *kaddr = scrub_stripe_get_kaddr(stripe, sector_nr); > + > + __bio_add_page(&bbio->bio, virt_to_page(kaddr), > + bbio->fs_info->sectorsize, offset_in_page(kaddr)); > +} > + > static void scrub_stripe_submit_repair_read(struct scrub_stripe *stripe, > int mirror, int blocksize, bool wait) > { > @@ -829,13 +821,6 @@ static void scrub_stripe_submit_repair_read(struct scrub_stripe *stripe, > ASSERT(atomic_read(&stripe->pending_io) == 0); > > for_each_set_bit(i, &old_error_bitmap, stripe->nr_sectors) { > - struct page *page; > - int pgoff; > - int ret; > - > - page = scrub_stripe_get_page(stripe, i); > - pgoff = scrub_stripe_get_page_offset(stripe, i); > - > /* The current sector cannot be merged, submit the bio. */ > if (bbio && ((i > 0 && !test_bit(i - 1, &stripe->error_bitmap)) || > bbio->bio.bi_iter.bi_size >= blocksize)) { > @@ -854,8 +839,7 @@ static void scrub_stripe_submit_repair_read(struct scrub_stripe *stripe, > (i << fs_info->sectorsize_bits)) >> SECTOR_SHIFT; > } > > - ret = bio_add_page(&bbio->bio, page, fs_info->sectorsize, pgoff); > - ASSERT(ret == fs_info->sectorsize); > + scrub_bio_add_sector(bbio, stripe, i); > } > if (bbio) { > ASSERT(bbio->bio.bi_iter.bi_size); > @@ -1202,10 +1186,6 @@ static void scrub_write_sectors(struct scrub_ctx *sctx, struct scrub_stripe *str > int sector_nr; > > for_each_set_bit(sector_nr, &write_bitmap, stripe->nr_sectors) { > - struct page *page = scrub_stripe_get_page(stripe, sector_nr); > - unsigned int pgoff = scrub_stripe_get_page_offset(stripe, sector_nr); > - int ret; > - > /* We should only writeback sectors covered by an extent. */ > ASSERT(test_bit(sector_nr, &stripe->extent_sector_bitmap)); > > @@ -1221,8 +1201,7 @@ static void scrub_write_sectors(struct scrub_ctx *sctx, struct scrub_stripe *str > (sector_nr << fs_info->sectorsize_bits)) >> > SECTOR_SHIFT; > } > - ret = bio_add_page(&bbio->bio, page, fs_info->sectorsize, pgoff); > - ASSERT(ret == fs_info->sectorsize); > + scrub_bio_add_sector(bbio, stripe, sector_nr); > } > if (bbio) > scrub_submit_write_bio(sctx, stripe, bbio, dev_replace); > @@ -1675,9 +1654,6 @@ static void scrub_submit_extent_sector_read(struct scrub_stripe *stripe) > atomic_inc(&stripe->pending_io); > > for_each_set_bit(i, &stripe->extent_sector_bitmap, stripe->nr_sectors) { > - struct page *page = scrub_stripe_get_page(stripe, i); > - unsigned int pgoff = scrub_stripe_get_page_offset(stripe, i); > - > /* We're beyond the chunk boundary, no need to read anymore. */ > if (i >= nr_sectors) > break; > @@ -1730,7 +1706,7 @@ static void scrub_submit_extent_sector_read(struct scrub_stripe *stripe) > bbio->bio.bi_iter.bi_sector = logical >> SECTOR_SHIFT; > } > > - __bio_add_page(&bbio->bio, page, fs_info->sectorsize, pgoff); > + scrub_bio_add_sector(bbio, stripe, i); > } > > if (bbio) { > @@ -1768,15 +1744,8 @@ static void scrub_submit_initial_read(struct scrub_ctx *sctx, > > bbio->bio.bi_iter.bi_sector = stripe->logical >> SECTOR_SHIFT; > /* Read the whole range inside the chunk boundary. */ > - for (unsigned int cur = 0; cur < nr_sectors; cur++) { > - struct page *page = scrub_stripe_get_page(stripe, cur); > - unsigned int pgoff = scrub_stripe_get_page_offset(stripe, cur); > - int ret; > - > - ret = bio_add_page(&bbio->bio, page, fs_info->sectorsize, pgoff); > - /* We should have allocated enough bio vectors. */ > - ASSERT(ret == fs_info->sectorsize); > - } > + for (unsigned int cur = 0; cur < nr_sectors; cur++) > + scrub_bio_add_sector(bbio, stripe, cur); > atomic_inc(&stripe->pending_io); > > /*
diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c index 49021765c17b..d014b728eb0d 100644 --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -579,20 +579,13 @@ static int fill_writer_pointer_gap(struct scrub_ctx *sctx, u64 physical) return ret; } -static struct page *scrub_stripe_get_page(struct scrub_stripe *stripe, int sector_nr) +static void *scrub_stripe_get_kaddr(struct scrub_stripe *stripe, int sector_nr) { struct btrfs_fs_info *fs_info = stripe->bg->fs_info; - int page_index = (sector_nr << fs_info->sectorsize_bits) >> PAGE_SHIFT; + u32 offset = sector_nr << fs_info->sectorsize_bits; - return stripe->pages[page_index]; -} - -static unsigned int scrub_stripe_get_page_offset(struct scrub_stripe *stripe, - int sector_nr) -{ - struct btrfs_fs_info *fs_info = stripe->bg->fs_info; - - return offset_in_page(sector_nr << fs_info->sectorsize_bits); + return page_address(stripe->pages[offset >> PAGE_SHIFT]) + + offset_in_page(offset); } static void scrub_verify_one_metadata(struct scrub_stripe *stripe, int sector_nr) @@ -600,19 +593,17 @@ static void scrub_verify_one_metadata(struct scrub_stripe *stripe, int sector_nr struct btrfs_fs_info *fs_info = stripe->bg->fs_info; const u32 sectors_per_tree = fs_info->nodesize >> fs_info->sectorsize_bits; const u64 logical = stripe->logical + (sector_nr << fs_info->sectorsize_bits); - const struct page *first_page = scrub_stripe_get_page(stripe, sector_nr); - const unsigned int first_off = scrub_stripe_get_page_offset(stripe, sector_nr); + void *first_kaddr = scrub_stripe_get_kaddr(stripe, sector_nr); SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); u8 on_disk_csum[BTRFS_CSUM_SIZE]; u8 calculated_csum[BTRFS_CSUM_SIZE]; - struct btrfs_header *header; + struct btrfs_header *header = first_kaddr; /* * Here we don't have a good way to attach the pages (and subpages) * to a dummy extent buffer, thus we have to directly grab the members * from pages. */ - header = (struct btrfs_header *)(page_address(first_page) + first_off); memcpy(on_disk_csum, header->csum, fs_info->csum_size); if (logical != btrfs_stack_header_bytenr(header)) { @@ -648,14 +639,11 @@ static void scrub_verify_one_metadata(struct scrub_stripe *stripe, int sector_nr /* Now check tree block csum. */ shash->tfm = fs_info->csum_shash; crypto_shash_init(shash); - crypto_shash_update(shash, page_address(first_page) + first_off + - BTRFS_CSUM_SIZE, fs_info->sectorsize - BTRFS_CSUM_SIZE); + crypto_shash_update(shash, first_kaddr + BTRFS_CSUM_SIZE, + fs_info->sectorsize - BTRFS_CSUM_SIZE); for (int i = sector_nr + 1; i < sector_nr + sectors_per_tree; i++) { - struct page *page = scrub_stripe_get_page(stripe, i); - unsigned int page_off = scrub_stripe_get_page_offset(stripe, i); - - crypto_shash_update(shash, page_address(page) + page_off, + crypto_shash_update(shash, scrub_stripe_get_kaddr(stripe, i), fs_info->sectorsize); } @@ -691,10 +679,8 @@ static void scrub_verify_one_sector(struct scrub_stripe *stripe, int sector_nr) struct btrfs_fs_info *fs_info = stripe->bg->fs_info; struct scrub_sector_verification *sector = &stripe->sectors[sector_nr]; const u32 sectors_per_tree = fs_info->nodesize >> fs_info->sectorsize_bits; - struct page *page = scrub_stripe_get_page(stripe, sector_nr); - unsigned int pgoff = scrub_stripe_get_page_offset(stripe, sector_nr); + void *kaddr = scrub_stripe_get_kaddr(stripe, sector_nr); u8 csum_buf[BTRFS_CSUM_SIZE]; - void *kaddr; int ret; ASSERT(sector_nr >= 0 && sector_nr < stripe->nr_sectors); @@ -738,9 +724,7 @@ static void scrub_verify_one_sector(struct scrub_stripe *stripe, int sector_nr) return; } - kaddr = kmap_local_page(page) + pgoff; ret = btrfs_check_sector_csum(fs_info, kaddr, csum_buf, sector->csum); - kunmap_local(kaddr); if (ret < 0) { set_bit(sector_nr, &stripe->csum_error_bitmap); set_bit(sector_nr, &stripe->error_bitmap); @@ -769,8 +753,7 @@ static int calc_sector_number(struct scrub_stripe *stripe, struct bio_vec *first int i; for (i = 0; i < stripe->nr_sectors; i++) { - if (scrub_stripe_get_page(stripe, i) == first_bvec->bv_page && - scrub_stripe_get_page_offset(stripe, i) == first_bvec->bv_offset) + if (scrub_stripe_get_kaddr(stripe, i) == bvec_virt(first_bvec)) break; } ASSERT(i < stripe->nr_sectors); @@ -817,6 +800,15 @@ static int calc_next_mirror(int mirror, int num_copies) return (mirror + 1 > num_copies) ? 1 : mirror + 1; } +static void scrub_bio_add_sector(struct btrfs_bio *bbio, + struct scrub_stripe *stripe, int sector_nr) +{ + void *kaddr = scrub_stripe_get_kaddr(stripe, sector_nr); + + __bio_add_page(&bbio->bio, virt_to_page(kaddr), + bbio->fs_info->sectorsize, offset_in_page(kaddr)); +} + static void scrub_stripe_submit_repair_read(struct scrub_stripe *stripe, int mirror, int blocksize, bool wait) { @@ -829,13 +821,6 @@ static void scrub_stripe_submit_repair_read(struct scrub_stripe *stripe, ASSERT(atomic_read(&stripe->pending_io) == 0); for_each_set_bit(i, &old_error_bitmap, stripe->nr_sectors) { - struct page *page; - int pgoff; - int ret; - - page = scrub_stripe_get_page(stripe, i); - pgoff = scrub_stripe_get_page_offset(stripe, i); - /* The current sector cannot be merged, submit the bio. */ if (bbio && ((i > 0 && !test_bit(i - 1, &stripe->error_bitmap)) || bbio->bio.bi_iter.bi_size >= blocksize)) { @@ -854,8 +839,7 @@ static void scrub_stripe_submit_repair_read(struct scrub_stripe *stripe, (i << fs_info->sectorsize_bits)) >> SECTOR_SHIFT; } - ret = bio_add_page(&bbio->bio, page, fs_info->sectorsize, pgoff); - ASSERT(ret == fs_info->sectorsize); + scrub_bio_add_sector(bbio, stripe, i); } if (bbio) { ASSERT(bbio->bio.bi_iter.bi_size); @@ -1202,10 +1186,6 @@ static void scrub_write_sectors(struct scrub_ctx *sctx, struct scrub_stripe *str int sector_nr; for_each_set_bit(sector_nr, &write_bitmap, stripe->nr_sectors) { - struct page *page = scrub_stripe_get_page(stripe, sector_nr); - unsigned int pgoff = scrub_stripe_get_page_offset(stripe, sector_nr); - int ret; - /* We should only writeback sectors covered by an extent. */ ASSERT(test_bit(sector_nr, &stripe->extent_sector_bitmap)); @@ -1221,8 +1201,7 @@ static void scrub_write_sectors(struct scrub_ctx *sctx, struct scrub_stripe *str (sector_nr << fs_info->sectorsize_bits)) >> SECTOR_SHIFT; } - ret = bio_add_page(&bbio->bio, page, fs_info->sectorsize, pgoff); - ASSERT(ret == fs_info->sectorsize); + scrub_bio_add_sector(bbio, stripe, sector_nr); } if (bbio) scrub_submit_write_bio(sctx, stripe, bbio, dev_replace); @@ -1675,9 +1654,6 @@ static void scrub_submit_extent_sector_read(struct scrub_stripe *stripe) atomic_inc(&stripe->pending_io); for_each_set_bit(i, &stripe->extent_sector_bitmap, stripe->nr_sectors) { - struct page *page = scrub_stripe_get_page(stripe, i); - unsigned int pgoff = scrub_stripe_get_page_offset(stripe, i); - /* We're beyond the chunk boundary, no need to read anymore. */ if (i >= nr_sectors) break; @@ -1730,7 +1706,7 @@ static void scrub_submit_extent_sector_read(struct scrub_stripe *stripe) bbio->bio.bi_iter.bi_sector = logical >> SECTOR_SHIFT; } - __bio_add_page(&bbio->bio, page, fs_info->sectorsize, pgoff); + scrub_bio_add_sector(bbio, stripe, i); } if (bbio) { @@ -1768,15 +1744,8 @@ static void scrub_submit_initial_read(struct scrub_ctx *sctx, bbio->bio.bi_iter.bi_sector = stripe->logical >> SECTOR_SHIFT; /* Read the whole range inside the chunk boundary. */ - for (unsigned int cur = 0; cur < nr_sectors; cur++) { - struct page *page = scrub_stripe_get_page(stripe, cur); - unsigned int pgoff = scrub_stripe_get_page_offset(stripe, cur); - int ret; - - ret = bio_add_page(&bbio->bio, page, fs_info->sectorsize, pgoff); - /* We should have allocated enough bio vectors. */ - ASSERT(ret == fs_info->sectorsize); - } + for (unsigned int cur = 0; cur < nr_sectors; cur++) + scrub_bio_add_sector(bbio, stripe, cur); atomic_inc(&stripe->pending_io); /*
Add a helper to get the actual kernel address of a stripe instead of just the page and offset into it to simplify the code, and add another helper to add the memory backing a sector to a bio using the above helper. This nicely abstracts away the page + offset representation from almost all of the scrub code. Signed-off-by: Christoph Hellwig <hch@lst.de> --- fs/btrfs/scrub.c | 81 +++++++++++++++--------------------------------- 1 file changed, 25 insertions(+), 56 deletions(-)