diff options
Diffstat (limited to 'fs/btrfs/compression.c')
| -rw-r--r-- | fs/btrfs/compression.c | 1566 |
1 files changed, 825 insertions, 741 deletions
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index 548057630b69..6b3357287b42 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -8,24 +8,34 @@ #include <linux/file.h> #include <linux/fs.h> #include <linux/pagemap.h> +#include <linux/pagevec.h> #include <linux/highmem.h> +#include <linux/kthread.h> #include <linux/time.h> #include <linux/init.h> #include <linux/string.h> #include <linux/backing-dev.h> #include <linux/writeback.h> +#include <linux/psi.h> #include <linux/slab.h> #include <linux/sched/mm.h> #include <linux/log2.h> +#include <linux/shrinker.h> +#include <crypto/hash.h> +#include "misc.h" #include "ctree.h" -#include "disk-io.h" -#include "transaction.h" +#include "fs.h" #include "btrfs_inode.h" -#include "volumes.h" +#include "bio.h" #include "ordered-data.h" #include "compression.h" #include "extent_io.h" #include "extent_map.h" +#include "subpage.h" +#include "messages.h" +#include "super.h" + +static struct bio_set btrfs_compressed_bioset; static const char* const btrfs_compress_types[] = { "", "zlib", "lzo", "zstd" }; @@ -37,241 +47,314 @@ const char* btrfs_compress_type2str(enum btrfs_compression_type type) case BTRFS_COMPRESS_ZSTD: case BTRFS_COMPRESS_NONE: return btrfs_compress_types[type]; + default: + break; } return NULL; } -static int btrfs_decompress_bio(struct compressed_bio *cb); +static inline struct compressed_bio *to_compressed_bio(struct btrfs_bio *bbio) +{ + return container_of(bbio, struct compressed_bio, bbio); +} -static inline int compressed_bio_size(struct btrfs_fs_info *fs_info, - unsigned long disk_size) +static struct compressed_bio *alloc_compressed_bio(struct btrfs_inode *inode, + u64 start, blk_opf_t op, + btrfs_bio_end_io_t end_io) { - u16 csum_size = btrfs_super_csum_size(fs_info->super_copy); + struct btrfs_bio *bbio; - return sizeof(struct compressed_bio) + - (DIV_ROUND_UP(disk_size, fs_info->sectorsize)) * csum_size; + bbio = btrfs_bio(bio_alloc_bioset(NULL, BTRFS_MAX_COMPRESSED_PAGES, op, + GFP_NOFS, &btrfs_compressed_bioset)); + btrfs_bio_init(bbio, inode, start, end_io, NULL); + return to_compressed_bio(bbio); } -static int check_compressed_csum(struct btrfs_inode *inode, - struct compressed_bio *cb, - u64 disk_start) +bool btrfs_compress_is_valid_type(const char *str, size_t len) { - int ret; - struct page *page; - unsigned long i; - char *kaddr; - u32 csum; - u32 *cb_sum = &cb->sums; + int i; - if (inode->flags & BTRFS_INODE_NODATASUM) - return 0; + for (i = 1; i < ARRAY_SIZE(btrfs_compress_types); i++) { + size_t comp_len = strlen(btrfs_compress_types[i]); - for (i = 0; i < cb->nr_pages; i++) { - page = cb->compressed_pages[i]; - csum = ~(u32)0; + if (len < comp_len) + continue; - kaddr = kmap_atomic(page); - csum = btrfs_csum_data(kaddr, csum, PAGE_SIZE); - btrfs_csum_final(csum, (u8 *)&csum); - kunmap_atomic(kaddr); + if (!strncmp(btrfs_compress_types[i], str, comp_len)) + return true; + } + return false; +} - if (csum != *cb_sum) { - btrfs_print_data_csum_error(inode, disk_start, csum, - *cb_sum, cb->mirror_num); - ret = -EIO; - goto fail; - } - cb_sum++; +static int compression_compress_pages(int type, struct list_head *ws, + struct btrfs_inode *inode, u64 start, + struct folio **folios, unsigned long *out_folios, + unsigned long *total_in, unsigned long *total_out) +{ + switch (type) { + case BTRFS_COMPRESS_ZLIB: + return zlib_compress_folios(ws, inode, start, folios, + out_folios, total_in, total_out); + case BTRFS_COMPRESS_LZO: + return lzo_compress_folios(ws, inode, start, folios, + out_folios, total_in, total_out); + case BTRFS_COMPRESS_ZSTD: + return zstd_compress_folios(ws, inode, start, folios, + out_folios, total_in, total_out); + case BTRFS_COMPRESS_NONE: + default: + /* + * This can happen when compression races with remount setting + * it to 'no compress', while caller doesn't call + * inode_need_compress() to check if we really need to + * compress. + * + * Not a big deal, just need to inform caller that we + * haven't allocated any pages yet. + */ + *out_folios = 0; + return -E2BIG; + } +} +static int compression_decompress_bio(struct list_head *ws, + struct compressed_bio *cb) +{ + switch (cb->compress_type) { + case BTRFS_COMPRESS_ZLIB: return zlib_decompress_bio(ws, cb); + case BTRFS_COMPRESS_LZO: return lzo_decompress_bio(ws, cb); + case BTRFS_COMPRESS_ZSTD: return zstd_decompress_bio(ws, cb); + case BTRFS_COMPRESS_NONE: + default: + /* + * This can't happen, the type is validated several times + * before we get here. + */ + BUG(); } - ret = 0; -fail: - return ret; } -/* when we finish reading compressed pages from the disk, we - * decompress them and then run the bio end_io routines on the - * decompressed pages (in the inode address space). - * - * This allows the checksumming and other IO error handling routines - * to work normally - * - * The compressed pages are freed here, and it must be run - * in process context - */ -static void end_compressed_bio_read(struct bio *bio) +static int compression_decompress(int type, struct list_head *ws, + const u8 *data_in, struct folio *dest_folio, + unsigned long dest_pgoff, size_t srclen, size_t destlen) { - struct compressed_bio *cb = bio->bi_private; - struct inode *inode; - struct page *page; - unsigned long index; - unsigned int mirror = btrfs_io_bio(bio)->mirror_num; - int ret = 0; + switch (type) { + case BTRFS_COMPRESS_ZLIB: return zlib_decompress(ws, data_in, dest_folio, + dest_pgoff, srclen, destlen); + case BTRFS_COMPRESS_LZO: return lzo_decompress(ws, data_in, dest_folio, + dest_pgoff, srclen, destlen); + case BTRFS_COMPRESS_ZSTD: return zstd_decompress(ws, data_in, dest_folio, + dest_pgoff, srclen, destlen); + case BTRFS_COMPRESS_NONE: + default: + /* + * This can't happen, the type is validated several times + * before we get here. + */ + BUG(); + } +} - if (bio->bi_status) - cb->errors = 1; +static void btrfs_free_compressed_folios(struct compressed_bio *cb) +{ + for (unsigned int i = 0; i < cb->nr_folios; i++) + btrfs_free_compr_folio(cb->compressed_folios[i]); + kfree(cb->compressed_folios); +} - /* if there are more bios still pending for this compressed - * extent, just exit - */ - if (!refcount_dec_and_test(&cb->pending_bios)) - goto out; +static int btrfs_decompress_bio(struct compressed_bio *cb); - /* - * Record the correct mirror_num in cb->orig_bio so that - * read-repair can work properly. - */ - ASSERT(btrfs_io_bio(cb->orig_bio)); - btrfs_io_bio(cb->orig_bio)->mirror_num = mirror; - cb->mirror_num = mirror; +/* + * Global cache of last unused pages for compression/decompression. + */ +static struct btrfs_compr_pool { + struct shrinker *shrinker; + spinlock_t lock; + struct list_head list; + int count; + int thresh; +} compr_pool; + +static unsigned long btrfs_compr_pool_count(struct shrinker *sh, struct shrink_control *sc) +{ + int ret; /* - * Some IO in this cb have failed, just skip checksum as there - * is no way it could be correct. + * We must not read the values more than once if 'ret' gets expanded in + * the return statement so we don't accidentally return a negative + * number, even if the first condition finds it positive. */ - if (cb->errors == 1) - goto csum_failed; + ret = READ_ONCE(compr_pool.count) - READ_ONCE(compr_pool.thresh); - inode = cb->inode; - ret = check_compressed_csum(BTRFS_I(inode), cb, - (u64)bio->bi_iter.bi_sector << 9); - if (ret) - goto csum_failed; + return ret > 0 ? ret : 0; +} - /* ok, we're the last bio for this extent, lets start - * the decompression. - */ - ret = btrfs_decompress_bio(cb); +static unsigned long btrfs_compr_pool_scan(struct shrinker *sh, struct shrink_control *sc) +{ + LIST_HEAD(remove); + struct list_head *tmp, *next; + int freed; -csum_failed: - if (ret) - cb->errors = 1; + if (compr_pool.count == 0) + return SHRINK_STOP; + + /* For now, just simply drain the whole list. */ + spin_lock(&compr_pool.lock); + list_splice_init(&compr_pool.list, &remove); + freed = compr_pool.count; + compr_pool.count = 0; + spin_unlock(&compr_pool.lock); + + list_for_each_safe(tmp, next, &remove) { + struct page *page = list_entry(tmp, struct page, lru); - /* release the compressed pages */ - index = 0; - for (index = 0; index < cb->nr_pages; index++) { - page = cb->compressed_pages[index]; - page->mapping = NULL; + ASSERT(page_ref_count(page) == 1); put_page(page); } - /* do io completion on the original bio */ - if (cb->errors) { - bio_io_error(cb->orig_bio); - } else { - int i; - struct bio_vec *bvec; + return freed; +} - /* - * we have verified the checksum already, set page - * checked so the end_io handlers know about it - */ - ASSERT(!bio_flagged(bio, BIO_CLONED)); - bio_for_each_segment_all(bvec, cb->orig_bio, i) - SetPageChecked(bvec->bv_page); +/* + * Common wrappers for page allocation from compression wrappers + */ +struct folio *btrfs_alloc_compr_folio(struct btrfs_fs_info *fs_info) +{ + struct folio *folio = NULL; + + /* For bs > ps cases, no cached folio pool for now. */ + if (fs_info->block_min_order) + goto alloc; - bio_endio(cb->orig_bio); + spin_lock(&compr_pool.lock); + if (compr_pool.count > 0) { + folio = list_first_entry(&compr_pool.list, struct folio, lru); + list_del_init(&folio->lru); + compr_pool.count--; } + spin_unlock(&compr_pool.lock); - /* finally free the cb struct */ - kfree(cb->compressed_pages); - kfree(cb); -out: - bio_put(bio); + if (folio) + return folio; + +alloc: + return folio_alloc(GFP_NOFS, fs_info->block_min_order); +} + +void btrfs_free_compr_folio(struct folio *folio) +{ + bool do_free = false; + + /* The folio is from bs > ps fs, no cached pool for now. */ + if (folio_order(folio)) + goto free; + + spin_lock(&compr_pool.lock); + if (compr_pool.count > compr_pool.thresh) { + do_free = true; + } else { + list_add(&folio->lru, &compr_pool.list); + compr_pool.count++; + } + spin_unlock(&compr_pool.lock); + + if (!do_free) + return; + +free: + ASSERT(folio_ref_count(folio) == 1); + folio_put(folio); +} + +static void end_bbio_compressed_read(struct btrfs_bio *bbio) +{ + struct compressed_bio *cb = to_compressed_bio(bbio); + blk_status_t status = bbio->bio.bi_status; + + if (!status) + status = errno_to_blk_status(btrfs_decompress_bio(cb)); + + btrfs_free_compressed_folios(cb); + btrfs_bio_end_io(cb->orig_bbio, status); + bio_put(&bbio->bio); } /* * Clear the writeback bits on all of the file * pages for a compressed write */ -static noinline void end_compressed_writeback(struct inode *inode, - const struct compressed_bio *cb) +static noinline void end_compressed_writeback(const struct compressed_bio *cb) { - unsigned long index = cb->start >> PAGE_SHIFT; - unsigned long end_index = (cb->start + cb->len - 1) >> PAGE_SHIFT; - struct page *pages[16]; - unsigned long nr_pages = end_index - index + 1; + struct inode *inode = &cb->bbio.inode->vfs_inode; + struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); + pgoff_t index = cb->start >> PAGE_SHIFT; + const pgoff_t end_index = (cb->start + cb->len - 1) >> PAGE_SHIFT; + struct folio_batch fbatch; int i; int ret; - if (cb->errors) - mapping_set_error(inode->i_mapping, -EIO); + ret = blk_status_to_errno(cb->bbio.bio.bi_status); + if (ret) + mapping_set_error(inode->i_mapping, ret); + + folio_batch_init(&fbatch); + while (index <= end_index) { + ret = filemap_get_folios(inode->i_mapping, &index, end_index, + &fbatch); + + if (ret == 0) + return; - while (nr_pages > 0) { - ret = find_get_pages_contig(inode->i_mapping, index, - min_t(unsigned long, - nr_pages, ARRAY_SIZE(pages)), pages); - if (ret == 0) { - nr_pages -= 1; - index += 1; - continue; - } for (i = 0; i < ret; i++) { - if (cb->errors) - SetPageError(pages[i]); - end_page_writeback(pages[i]); - put_page(pages[i]); + struct folio *folio = fbatch.folios[i]; + + btrfs_folio_clamp_clear_writeback(fs_info, folio, + cb->start, cb->len); } - nr_pages -= ret; - index += ret; + folio_batch_release(&fbatch); } /* the inode may be gone now */ } /* - * do the cleanup once all the compressed pages hit the disk. - * This will clear writeback on the file pages and free the compressed - * pages. + * Do the cleanup once all the compressed pages hit the disk. This will clear + * writeback on the file pages and free the compressed pages. * - * This also calls the writeback end hooks for the file pages so that - * metadata and checksums can be updated in the file. + * This also calls the writeback end hooks for the file pages so that metadata + * and checksums can be updated in the file. */ -static void end_compressed_bio_write(struct bio *bio) +static void end_bbio_compressed_write(struct btrfs_bio *bbio) { - struct compressed_bio *cb = bio->bi_private; - struct inode *inode; - struct page *page; - unsigned long index; - - if (bio->bi_status) - cb->errors = 1; - - /* if there are more bios still pending for this compressed - * extent, just exit - */ - if (!refcount_dec_and_test(&cb->pending_bios)) - goto out; + struct compressed_bio *cb = to_compressed_bio(bbio); - /* ok, we're the last bio for this extent, step one is to - * call back into the FS and do all the end_io operations - */ - inode = cb->inode; - cb->compressed_pages[0]->mapping = cb->inode->i_mapping; - btrfs_writepage_endio_finish_ordered(cb->compressed_pages[0], - cb->start, cb->start + cb->len - 1, - bio->bi_status ? BLK_STS_OK : BLK_STS_NOTSUPP); - cb->compressed_pages[0]->mapping = NULL; + btrfs_finish_ordered_extent(cb->bbio.ordered, NULL, cb->start, cb->len, + cb->bbio.bio.bi_status == BLK_STS_OK); - end_compressed_writeback(inode, cb); - /* note, our inode could be gone now */ + if (cb->writeback) + end_compressed_writeback(cb); + /* Note, our inode could be gone now. */ + btrfs_free_compressed_folios(cb); + bio_put(&cb->bbio.bio); +} - /* - * release the compressed pages, these came from alloc_page and - * are not attached to the inode at all - */ - index = 0; - for (index = 0; index < cb->nr_pages; index++) { - page = cb->compressed_pages[index]; - page->mapping = NULL; - put_page(page); +static void btrfs_add_compressed_bio_folios(struct compressed_bio *cb) +{ + struct bio *bio = &cb->bbio.bio; + u32 offset = 0; + unsigned int findex = 0; + + while (offset < cb->compressed_len) { + struct folio *folio = cb->compressed_folios[findex]; + u32 len = min_t(u32, cb->compressed_len - offset, folio_size(folio)); + int ret; + + /* Maximum compressed extent is smaller than bio size limit. */ + ret = bio_add_folio(bio, folio, len, 0); + ASSERT(ret); + offset += len; + findex++; } - - /* finally free the cb struct */ - kfree(cb->compressed_pages); - kfree(cb); -out: - bio_put(bio); } /* @@ -283,226 +366,189 @@ out: * This also checksums the file bytes and gets things ready for * the end io hooks. */ -blk_status_t btrfs_submit_compressed_write(struct inode *inode, u64 start, - unsigned long len, u64 disk_start, - unsigned long compressed_len, - struct page **compressed_pages, - unsigned long nr_pages, - unsigned int write_flags) +void btrfs_submit_compressed_write(struct btrfs_ordered_extent *ordered, + struct folio **compressed_folios, + unsigned int nr_folios, + blk_opf_t write_flags, + bool writeback) { - struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); - struct bio *bio = NULL; + struct btrfs_inode *inode = ordered->inode; + struct btrfs_fs_info *fs_info = inode->root->fs_info; struct compressed_bio *cb; - unsigned long bytes_left; - int pg_index = 0; - struct page *page; - u64 first_byte = disk_start; - struct block_device *bdev; - blk_status_t ret; - int skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; - - WARN_ON(!PAGE_ALIGNED(start)); - cb = kmalloc(compressed_bio_size(fs_info, compressed_len), GFP_NOFS); - if (!cb) - return BLK_STS_RESOURCE; - refcount_set(&cb->pending_bios, 0); - cb->errors = 0; - cb->inode = inode; - cb->start = start; - cb->len = len; - cb->mirror_num = 0; - cb->compressed_pages = compressed_pages; - cb->compressed_len = compressed_len; - cb->orig_bio = NULL; - cb->nr_pages = nr_pages; - - bdev = fs_info->fs_devices->latest_bdev; - - bio = btrfs_bio_alloc(bdev, first_byte); - bio->bi_opf = REQ_OP_WRITE | write_flags; - bio->bi_private = cb; - bio->bi_end_io = end_compressed_bio_write; - refcount_set(&cb->pending_bios, 1); - - /* create and submit bios for the compressed pages */ - bytes_left = compressed_len; - for (pg_index = 0; pg_index < cb->nr_pages; pg_index++) { - int submit = 0; - - page = compressed_pages[pg_index]; - page->mapping = inode->i_mapping; - if (bio->bi_iter.bi_size) - submit = btrfs_bio_fits_in_stripe(page, PAGE_SIZE, bio, - 0); - - page->mapping = NULL; - if (submit || bio_add_page(bio, page, PAGE_SIZE, 0) < - PAGE_SIZE) { - /* - * inc the count before we submit the bio so - * we know the end IO handler won't happen before - * we inc the count. Otherwise, the cb might get - * freed before we're done setting it up - */ - refcount_inc(&cb->pending_bios); - ret = btrfs_bio_wq_end_io(fs_info, bio, - BTRFS_WQ_ENDIO_DATA); - BUG_ON(ret); /* -ENOMEM */ - - if (!skip_sum) { - ret = btrfs_csum_one_bio(inode, bio, start, 1); - BUG_ON(ret); /* -ENOMEM */ - } - - ret = btrfs_map_bio(fs_info, bio, 0, 1); - if (ret) { - bio->bi_status = ret; - bio_endio(bio); - } - - bio = btrfs_bio_alloc(bdev, first_byte); - bio->bi_opf = REQ_OP_WRITE | write_flags; - bio->bi_private = cb; - bio->bi_end_io = end_compressed_bio_write; - bio_add_page(bio, page, PAGE_SIZE, 0); - } - if (bytes_left < PAGE_SIZE) { - btrfs_info(fs_info, - "bytes left %lu compress len %lu nr %lu", - bytes_left, cb->compressed_len, cb->nr_pages); - } - bytes_left -= PAGE_SIZE; - first_byte += PAGE_SIZE; - cond_resched(); - } - - ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DATA); - BUG_ON(ret); /* -ENOMEM */ - - if (!skip_sum) { - ret = btrfs_csum_one_bio(inode, bio, start, 1); - BUG_ON(ret); /* -ENOMEM */ - } - - ret = btrfs_map_bio(fs_info, bio, 0, 1); - if (ret) { - bio->bi_status = ret; - bio_endio(bio); - } - return 0; -} - -static u64 bio_end_offset(struct bio *bio) -{ - struct bio_vec *last = bio_last_bvec_all(bio); - - return page_offset(last->bv_page) + last->bv_len + last->bv_offset; + ASSERT(IS_ALIGNED(ordered->file_offset, fs_info->sectorsize)); + ASSERT(IS_ALIGNED(ordered->num_bytes, fs_info->sectorsize)); + + cb = alloc_compressed_bio(inode, ordered->file_offset, + REQ_OP_WRITE | write_flags, + end_bbio_compressed_write); + cb->start = ordered->file_offset; + cb->len = ordered->num_bytes; + cb->compressed_folios = compressed_folios; + cb->compressed_len = ordered->disk_num_bytes; + cb->writeback = writeback; + cb->nr_folios = nr_folios; + cb->bbio.bio.bi_iter.bi_sector = ordered->disk_bytenr >> SECTOR_SHIFT; + cb->bbio.ordered = ordered; + btrfs_add_compressed_bio_folios(cb); + + btrfs_submit_bbio(&cb->bbio, 0); } +/* + * Add extra pages in the same compressed file extent so that we don't need to + * re-read the same extent again and again. + * + * NOTE: this won't work well for subpage, as for subpage read, we lock the + * full page then submit bio for each compressed/regular extents. + * + * This means, if we have several sectors in the same page points to the same + * on-disk compressed data, we will re-read the same extent many times and + * this function can only help for the next page. + */ static noinline int add_ra_bio_pages(struct inode *inode, u64 compressed_end, - struct compressed_bio *cb) + struct compressed_bio *cb, + int *memstall, unsigned long *pflags) { - unsigned long end_index; - unsigned long pg_index; - u64 last_offset; + struct btrfs_fs_info *fs_info = inode_to_fs_info(inode); + pgoff_t end_index; + struct bio *orig_bio = &cb->orig_bbio->bio; + u64 cur = cb->orig_bbio->file_offset + orig_bio->bi_iter.bi_size; u64 isize = i_size_read(inode); int ret; - struct page *page; - unsigned long nr_pages = 0; + struct folio *folio; struct extent_map *em; struct address_space *mapping = inode->i_mapping; struct extent_map_tree *em_tree; struct extent_io_tree *tree; - u64 end; - int misses = 0; + int sectors_missed = 0; - last_offset = bio_end_offset(cb->orig_bio); em_tree = &BTRFS_I(inode)->extent_tree; tree = &BTRFS_I(inode)->io_tree; if (isize == 0) return 0; + /* + * For current subpage support, we only support 64K page size, + * which means maximum compressed extent size (128K) is just 2x page + * size. + * This makes readahead less effective, so here disable readahead for + * subpage for now, until full compressed write is supported. + */ + if (fs_info->sectorsize < PAGE_SIZE) + return 0; + + /* For bs > ps cases, we don't support readahead for compressed folios for now. */ + if (fs_info->block_min_order) + return 0; + end_index = (i_size_read(inode) - 1) >> PAGE_SHIFT; - while (last_offset < compressed_end) { - pg_index = last_offset >> PAGE_SHIFT; + while (cur < compressed_end) { + pgoff_t page_end; + pgoff_t pg_index = cur >> PAGE_SHIFT; + u32 add_size; if (pg_index > end_index) break; - page = xa_load(&mapping->i_pages, pg_index); - if (page && !xa_is_value(page)) { - misses++; - if (misses > 4) + folio = filemap_get_folio(mapping, pg_index); + if (!IS_ERR(folio)) { + u64 folio_sz = folio_size(folio); + u64 offset = offset_in_folio(folio, cur); + + folio_put(folio); + sectors_missed += (folio_sz - offset) >> + fs_info->sectorsize_bits; + + /* Beyond threshold, no need to continue */ + if (sectors_missed > 4) break; - goto next; + + /* + * Jump to next page start as we already have page for + * current offset. + */ + cur += (folio_sz - offset); + continue; } - page = __page_cache_alloc(mapping_gfp_constraint(mapping, - ~__GFP_FS)); - if (!page) + folio = filemap_alloc_folio(mapping_gfp_constraint(mapping, ~__GFP_FS), + 0, NULL); + if (!folio) break; - if (add_to_page_cache_lru(page, mapping, pg_index, GFP_NOFS)) { - put_page(page); - goto next; + if (filemap_add_folio(mapping, folio, pg_index, GFP_NOFS)) { + /* There is already a page, skip to page end */ + cur += folio_size(folio); + folio_put(folio); + continue; } - end = last_offset + PAGE_SIZE - 1; - /* - * at this point, we have a locked page in the page cache - * for these bytes in the file. But, we have to make - * sure they map to this compressed extent on disk. - */ - set_page_extent_mapped(page); - lock_extent(tree, last_offset, end); + if (!*memstall && folio_test_workingset(folio)) { + psi_memstall_enter(pflags); + *memstall = 1; + } + + ret = set_folio_extent_mapped(folio); + if (ret < 0) { + folio_unlock(folio); + folio_put(folio); + break; + } + + page_end = (pg_index << PAGE_SHIFT) + folio_size(folio) - 1; + btrfs_lock_extent(tree, cur, page_end, NULL); read_lock(&em_tree->lock); - em = lookup_extent_mapping(em_tree, last_offset, - PAGE_SIZE); + em = btrfs_lookup_extent_mapping(em_tree, cur, page_end + 1 - cur); read_unlock(&em_tree->lock); - if (!em || last_offset < em->start || - (last_offset + PAGE_SIZE > extent_map_end(em)) || - (em->block_start >> 9) != cb->orig_bio->bi_iter.bi_sector) { - free_extent_map(em); - unlock_extent(tree, last_offset, end); - unlock_page(page); - put_page(page); + /* + * At this point, we have a locked page in the page cache for + * these bytes in the file. But, we have to make sure they map + * to this compressed extent on disk. + */ + if (!em || cur < em->start || + (cur + fs_info->sectorsize > btrfs_extent_map_end(em)) || + (btrfs_extent_map_block_start(em) >> SECTOR_SHIFT) != + orig_bio->bi_iter.bi_sector) { + btrfs_free_extent_map(em); + btrfs_unlock_extent(tree, cur, page_end, NULL); + folio_unlock(folio); + folio_put(folio); break; } - free_extent_map(em); + add_size = min(em->start + em->len, page_end + 1) - cur; + btrfs_free_extent_map(em); + btrfs_unlock_extent(tree, cur, page_end, NULL); - if (page->index == end_index) { - char *userpage; - size_t zero_offset = offset_in_page(isize); + if (folio_contains(folio, end_index)) { + size_t zero_offset = offset_in_folio(folio, isize); if (zero_offset) { int zeros; - zeros = PAGE_SIZE - zero_offset; - userpage = kmap_atomic(page); - memset(userpage + zero_offset, 0, zeros); - flush_dcache_page(page); - kunmap_atomic(userpage); + zeros = folio_size(folio) - zero_offset; + folio_zero_range(folio, zero_offset, zeros); } } - ret = bio_add_page(cb->orig_bio, page, - PAGE_SIZE, 0); - - if (ret == PAGE_SIZE) { - nr_pages++; - put_page(page); - } else { - unlock_extent(tree, last_offset, end); - unlock_page(page); - put_page(page); + if (!bio_add_folio(orig_bio, folio, add_size, + offset_in_folio(folio, cur))) { + folio_unlock(folio); + folio_put(folio); break; } -next: - last_offset += PAGE_SIZE; + /* + * If it's subpage, we also need to increase its + * subpage::readers number, as at endio we will decrease + * subpage::readers and to unlock the page. + */ + if (fs_info->sectorsize < PAGE_SIZE) + btrfs_folio_set_lock(fs_info, folio, cur, add_size); + folio_put(folio); + cur += add_size; } return 0; } @@ -518,169 +564,83 @@ next: * After the compressed pages are read, we copy the bytes into the * bio we were passed and then call the bio end_io calls */ -blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, - int mirror_num, unsigned long bio_flags) +void btrfs_submit_compressed_read(struct btrfs_bio *bbio) { - struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); - struct extent_map_tree *em_tree; + struct btrfs_inode *inode = bbio->inode; + struct btrfs_fs_info *fs_info = inode->root->fs_info; + struct extent_map_tree *em_tree = &inode->extent_tree; struct compressed_bio *cb; - unsigned long compressed_len; - unsigned long nr_pages; - unsigned long pg_index; - struct page *page; - struct block_device *bdev; - struct bio *comp_bio; - u64 cur_disk_byte = (u64)bio->bi_iter.bi_sector << 9; + unsigned int compressed_len; + u64 file_offset = bbio->file_offset; u64 em_len; u64 em_start; struct extent_map *em; - blk_status_t ret = BLK_STS_RESOURCE; - int faili = 0; - u32 *sums; - - em_tree = &BTRFS_I(inode)->extent_tree; + unsigned long pflags; + int memstall = 0; + blk_status_t status; + int ret; /* we need the actual starting offset of this extent in the file */ read_lock(&em_tree->lock); - em = lookup_extent_mapping(em_tree, - page_offset(bio_first_page_all(bio)), - PAGE_SIZE); + em = btrfs_lookup_extent_mapping(em_tree, file_offset, fs_info->sectorsize); read_unlock(&em_tree->lock); - if (!em) - return BLK_STS_IOERR; - - compressed_len = em->block_len; - cb = kmalloc(compressed_bio_size(fs_info, compressed_len), GFP_NOFS); - if (!cb) + if (!em) { + status = BLK_STS_IOERR; goto out; + } + + ASSERT(btrfs_extent_map_is_compressed(em)); + compressed_len = em->disk_num_bytes; - refcount_set(&cb->pending_bios, 0); - cb->errors = 0; - cb->inode = inode; - cb->mirror_num = mirror_num; - sums = &cb->sums; + cb = alloc_compressed_bio(inode, file_offset, REQ_OP_READ, + end_bbio_compressed_read); - cb->start = em->orig_start; + cb->start = em->start - em->offset; em_len = em->len; em_start = em->start; - free_extent_map(em); - em = NULL; - - cb->len = bio->bi_iter.bi_size; + cb->len = bbio->bio.bi_iter.bi_size; cb->compressed_len = compressed_len; - cb->compress_type = extent_compress_type(bio_flags); - cb->orig_bio = bio; - - nr_pages = DIV_ROUND_UP(compressed_len, PAGE_SIZE); - cb->compressed_pages = kcalloc(nr_pages, sizeof(struct page *), - GFP_NOFS); - if (!cb->compressed_pages) - goto fail1; - - bdev = fs_info->fs_devices->latest_bdev; - - for (pg_index = 0; pg_index < nr_pages; pg_index++) { - cb->compressed_pages[pg_index] = alloc_page(GFP_NOFS | - __GFP_HIGHMEM); - if (!cb->compressed_pages[pg_index]) { - faili = pg_index - 1; - ret = BLK_STS_RESOURCE; - goto fail2; - } - } - faili = nr_pages - 1; - cb->nr_pages = nr_pages; - - add_ra_bio_pages(inode, em_start + em_len, cb); - - /* include any pages we added in add_ra-bio_pages */ - cb->len = bio->bi_iter.bi_size; - - comp_bio = btrfs_bio_alloc(bdev, cur_disk_byte); - comp_bio->bi_opf = REQ_OP_READ; - comp_bio->bi_private = cb; - comp_bio->bi_end_io = end_compressed_bio_read; - refcount_set(&cb->pending_bios, 1); - - for (pg_index = 0; pg_index < nr_pages; pg_index++) { - int submit = 0; - - page = cb->compressed_pages[pg_index]; - page->mapping = inode->i_mapping; - page->index = em_start >> PAGE_SHIFT; - - if (comp_bio->bi_iter.bi_size) - submit = btrfs_bio_fits_in_stripe(page, PAGE_SIZE, - comp_bio, 0); - - page->mapping = NULL; - if (submit || bio_add_page(comp_bio, page, PAGE_SIZE, 0) < - PAGE_SIZE) { - ret = btrfs_bio_wq_end_io(fs_info, comp_bio, - BTRFS_WQ_ENDIO_DATA); - BUG_ON(ret); /* -ENOMEM */ - - /* - * inc the count before we submit the bio so - * we know the end IO handler won't happen before - * we inc the count. Otherwise, the cb might get - * freed before we're done setting it up - */ - refcount_inc(&cb->pending_bios); - - if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) { - ret = btrfs_lookup_bio_sums(inode, comp_bio, - sums); - BUG_ON(ret); /* -ENOMEM */ - } - sums += DIV_ROUND_UP(comp_bio->bi_iter.bi_size, - fs_info->sectorsize); - - ret = btrfs_map_bio(fs_info, comp_bio, mirror_num, 0); - if (ret) { - comp_bio->bi_status = ret; - bio_endio(comp_bio); - } - - comp_bio = btrfs_bio_alloc(bdev, cur_disk_byte); - comp_bio->bi_opf = REQ_OP_READ; - comp_bio->bi_private = cb; - comp_bio->bi_end_io = end_compressed_bio_read; - - bio_add_page(comp_bio, page, PAGE_SIZE, 0); - } - cur_disk_byte += PAGE_SIZE; - } + cb->compress_type = btrfs_extent_map_compression(em); + cb->orig_bbio = bbio; + cb->bbio.csum_search_commit_root = bbio->csum_search_commit_root; - ret = btrfs_bio_wq_end_io(fs_info, comp_bio, BTRFS_WQ_ENDIO_DATA); - BUG_ON(ret); /* -ENOMEM */ + btrfs_free_extent_map(em); - if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) { - ret = btrfs_lookup_bio_sums(inode, comp_bio, sums); - BUG_ON(ret); /* -ENOMEM */ + cb->nr_folios = DIV_ROUND_UP(compressed_len, btrfs_min_folio_size(fs_info)); + cb->compressed_folios = kcalloc(cb->nr_folios, sizeof(struct folio *), GFP_NOFS); + if (!cb->compressed_folios) { + status = BLK_STS_RESOURCE; + goto out_free_bio; } - ret = btrfs_map_bio(fs_info, comp_bio, mirror_num, 0); + ret = btrfs_alloc_folio_array(cb->nr_folios, fs_info->block_min_order, + cb->compressed_folios); if (ret) { - comp_bio->bi_status = ret; - bio_endio(comp_bio); + status = BLK_STS_RESOURCE; + goto out_free_compressed_pages; } - return 0; + add_ra_bio_pages(&inode->vfs_inode, em_start + em_len, cb, &memstall, + &pflags); -fail2: - while (faili >= 0) { - __free_page(cb->compressed_pages[faili]); - faili--; - } + /* include any pages we added in add_ra-bio_pages */ + cb->len = bbio->bio.bi_iter.bi_size; + cb->bbio.bio.bi_iter.bi_sector = bbio->bio.bi_iter.bi_sector; + btrfs_add_compressed_bio_folios(cb); + + if (memstall) + psi_memstall_leave(&pflags); + + btrfs_submit_bbio(&cb->bbio, 0); + return; - kfree(cb->compressed_pages); -fail1: - kfree(cb); +out_free_compressed_pages: + kfree(cb->compressed_folios); +out_free_bio: + bio_put(&cb->bbio.bio); out: - free_extent_map(em); - return ret; + btrfs_bio_end_io(bbio, status); } /* @@ -742,7 +702,7 @@ static void free_heuristic_ws(struct list_head *ws) kfree(workspace); } -static struct list_head *alloc_heuristic_ws(void) +static struct list_head *alloc_heuristic_ws(struct btrfs_fs_info *fs_info) { struct heuristic_ws *ws; @@ -769,66 +729,100 @@ fail: return ERR_PTR(-ENOMEM); } -struct workspaces_list { - struct list_head idle_ws; - spinlock_t ws_lock; - /* Number of free workspaces */ - int free_ws; - /* Total number of allocated workspaces */ - atomic_t total_ws; - /* Waiters for a free workspace */ - wait_queue_head_t ws_wait; -}; - -static struct workspaces_list btrfs_comp_ws[BTRFS_COMPRESS_TYPES]; +const struct btrfs_compress_levels btrfs_heuristic_compress = { 0 }; -static struct workspaces_list btrfs_heuristic_ws; - -static const struct btrfs_compress_op * const btrfs_compress_op[] = { +static const struct btrfs_compress_levels * const btrfs_compress_levels[] = { + /* The heuristic is represented as compression type 0 */ + &btrfs_heuristic_compress, &btrfs_zlib_compress, &btrfs_lzo_compress, &btrfs_zstd_compress, }; -void __init btrfs_init_compress(void) +static struct list_head *alloc_workspace(struct btrfs_fs_info *fs_info, int type, int level) +{ + switch (type) { + case BTRFS_COMPRESS_NONE: return alloc_heuristic_ws(fs_info); + case BTRFS_COMPRESS_ZLIB: return zlib_alloc_workspace(fs_info, level); + case BTRFS_COMPRESS_LZO: return lzo_alloc_workspace(fs_info); + case BTRFS_COMPRESS_ZSTD: return zstd_alloc_workspace(fs_info, level); + default: + /* + * This can't happen, the type is validated several times + * before we get here. + */ + BUG(); + } +} + +static void free_workspace(int type, struct list_head *ws) +{ + switch (type) { + case BTRFS_COMPRESS_NONE: return free_heuristic_ws(ws); + case BTRFS_COMPRESS_ZLIB: return zlib_free_workspace(ws); + case BTRFS_COMPRESS_LZO: return lzo_free_workspace(ws); + case BTRFS_COMPRESS_ZSTD: return zstd_free_workspace(ws); + default: + /* + * This can't happen, the type is validated several times + * before we get here. + */ + BUG(); + } +} + +static int alloc_workspace_manager(struct btrfs_fs_info *fs_info, + enum btrfs_compression_type type) { + struct workspace_manager *gwsm; struct list_head *workspace; - int i; - INIT_LIST_HEAD(&btrfs_heuristic_ws.idle_ws); - spin_lock_init(&btrfs_heuristic_ws.ws_lock); - atomic_set(&btrfs_heuristic_ws.total_ws, 0); - init_waitqueue_head(&btrfs_heuristic_ws.ws_wait); + ASSERT(fs_info->compr_wsm[type] == NULL); + gwsm = kzalloc(sizeof(*gwsm), GFP_KERNEL); + if (!gwsm) + return -ENOMEM; - workspace = alloc_heuristic_ws(); + INIT_LIST_HEAD(&gwsm->idle_ws); + spin_lock_init(&gwsm->ws_lock); + atomic_set(&gwsm->total_ws, 0); + init_waitqueue_head(&gwsm->ws_wait); + fs_info->compr_wsm[type] = gwsm; + + /* + * Preallocate one workspace for each compression type so we can + * guarantee forward progress in the worst case + */ + workspace = alloc_workspace(fs_info, type, 0); if (IS_ERR(workspace)) { - pr_warn( - "BTRFS: cannot preallocate heuristic workspace, will try later\n"); + btrfs_warn(fs_info, + "cannot preallocate compression workspace for %s, will try later", + btrfs_compress_type2str(type)); } else { - atomic_set(&btrfs_heuristic_ws.total_ws, 1); - btrfs_heuristic_ws.free_ws = 1; - list_add(workspace, &btrfs_heuristic_ws.idle_ws); + atomic_set(&gwsm->total_ws, 1); + gwsm->free_ws = 1; + list_add(workspace, &gwsm->idle_ws); } + return 0; +} - for (i = 0; i < BTRFS_COMPRESS_TYPES; i++) { - INIT_LIST_HEAD(&btrfs_comp_ws[i].idle_ws); - spin_lock_init(&btrfs_comp_ws[i].ws_lock); - atomic_set(&btrfs_comp_ws[i].total_ws, 0); - init_waitqueue_head(&btrfs_comp_ws[i].ws_wait); - - /* - * Preallocate one workspace for each compression type so - * we can guarantee forward progress in the worst case - */ - workspace = btrfs_compress_op[i]->alloc_workspace(); - if (IS_ERR(workspace)) { - pr_warn("BTRFS: cannot preallocate compression workspace, will try later\n"); - } else { - atomic_set(&btrfs_comp_ws[i].total_ws, 1); - btrfs_comp_ws[i].free_ws = 1; - list_add(workspace, &btrfs_comp_ws[i].idle_ws); - } +static void free_workspace_manager(struct btrfs_fs_info *fs_info, + enum btrfs_compression_type type) +{ + struct list_head *ws; + struct workspace_manager *gwsm = fs_info->compr_wsm[type]; + + /* ZSTD uses its own workspace manager, should enter here. */ + ASSERT(type != BTRFS_COMPRESS_ZSTD && type < BTRFS_NR_COMPRESS_TYPES); + if (!gwsm) + return; + fs_info->compr_wsm[type] = NULL; + while (!list_empty(&gwsm->idle_ws)) { + ws = gwsm->idle_ws.next; + list_del(ws); + free_workspace(type, ws); + atomic_dec(&gwsm->total_ws); } + kfree(gwsm); } /* @@ -837,11 +831,11 @@ void __init btrfs_init_compress(void) * Preallocation makes a forward progress guarantees and we do not return * errors. */ -static struct list_head *__find_workspace(int type, bool heuristic) +struct list_head *btrfs_get_workspace(struct btrfs_fs_info *fs_info, int type, int level) { + struct workspace_manager *wsm = fs_info->compr_wsm[type]; struct list_head *workspace; int cpus = num_online_cpus(); - int idx = type - 1; unsigned nofs_flag; struct list_head *idle_ws; spinlock_t *ws_lock; @@ -849,19 +843,12 @@ static struct list_head *__find_workspace(int type, bool heuristic) wait_queue_head_t *ws_wait; int *free_ws; - if (heuristic) { - idle_ws = &btrfs_heuristic_ws.idle_ws; - ws_lock = &btrfs_heuristic_ws.ws_lock; - total_ws = &btrfs_heuristic_ws.total_ws; - ws_wait = &btrfs_heuristic_ws.ws_wait; - free_ws = &btrfs_heuristic_ws.free_ws; - } else { - idle_ws = &btrfs_comp_ws[idx].idle_ws; - ws_lock = &btrfs_comp_ws[idx].ws_lock; - total_ws = &btrfs_comp_ws[idx].total_ws; - ws_wait = &btrfs_comp_ws[idx].ws_wait; - free_ws = &btrfs_comp_ws[idx].free_ws; - } + ASSERT(wsm); + idle_ws = &wsm->idle_ws; + ws_lock = &wsm->ws_lock; + total_ws = &wsm->total_ws; + ws_wait = &wsm->ws_wait; + free_ws = &wsm->free_ws; again: spin_lock(ws_lock); @@ -892,10 +879,7 @@ again: * context of btrfs_compress_bio/btrfs_compress_pages */ nofs_flag = memalloc_nofs_save(); - if (heuristic) - workspace = alloc_heuristic_ws(); - else - workspace = btrfs_compress_op[idx]->alloc_workspace(); + workspace = alloc_workspace(fs_info, type, level); memalloc_nofs_restore(nofs_flag); if (IS_ERR(workspace)) { @@ -917,94 +901,129 @@ again: /* once per minute */ 60 * HZ, /* no burst */ 1); - if (__ratelimit(&_rs)) { - pr_warn("BTRFS: no compression workspaces, low memory, retrying\n"); - } + if (__ratelimit(&_rs)) + btrfs_warn(fs_info, + "no compression workspaces, low memory, retrying"); } goto again; } return workspace; } -static struct list_head *find_workspace(int type) +static struct list_head *get_workspace(struct btrfs_fs_info *fs_info, int type, int level) { - return __find_workspace(type, false); + switch (type) { + case BTRFS_COMPRESS_NONE: return btrfs_get_workspace(fs_info, type, level); + case BTRFS_COMPRESS_ZLIB: return zlib_get_workspace(fs_info, level); + case BTRFS_COMPRESS_LZO: return btrfs_get_workspace(fs_info, type, level); + case BTRFS_COMPRESS_ZSTD: return zstd_get_workspace(fs_info, level); + default: + /* + * This can't happen, the type is validated several times + * before we get here. + */ + BUG(); + } } /* * put a workspace struct back on the list or free it if we have enough * idle ones sitting around */ -static void __free_workspace(int type, struct list_head *workspace, - bool heuristic) +void btrfs_put_workspace(struct btrfs_fs_info *fs_info, int type, struct list_head *ws) { - int idx = type - 1; + struct workspace_manager *gwsm = fs_info->compr_wsm[type]; struct list_head *idle_ws; spinlock_t *ws_lock; atomic_t *total_ws; wait_queue_head_t *ws_wait; int *free_ws; - if (heuristic) { - idle_ws = &btrfs_heuristic_ws.idle_ws; - ws_lock = &btrfs_heuristic_ws.ws_lock; - total_ws = &btrfs_heuristic_ws.total_ws; - ws_wait = &btrfs_heuristic_ws.ws_wait; - free_ws = &btrfs_heuristic_ws.free_ws; - } else { - idle_ws = &btrfs_comp_ws[idx].idle_ws; - ws_lock = &btrfs_comp_ws[idx].ws_lock; - total_ws = &btrfs_comp_ws[idx].total_ws; - ws_wait = &btrfs_comp_ws[idx].ws_wait; - free_ws = &btrfs_comp_ws[idx].free_ws; - } + ASSERT(gwsm); + idle_ws = &gwsm->idle_ws; + ws_lock = &gwsm->ws_lock; + total_ws = &gwsm->total_ws; + ws_wait = &gwsm->ws_wait; + free_ws = &gwsm->free_ws; spin_lock(ws_lock); if (*free_ws <= num_online_cpus()) { - list_add(workspace, idle_ws); + list_add(ws, idle_ws); (*free_ws)++; spin_unlock(ws_lock); goto wake; } spin_unlock(ws_lock); - if (heuristic) - free_heuristic_ws(workspace); - else - btrfs_compress_op[idx]->free_workspace(workspace); + free_workspace(type, ws); atomic_dec(total_ws); wake: cond_wake_up(ws_wait); } -static void free_workspace(int type, struct list_head *ws) +static void put_workspace(struct btrfs_fs_info *fs_info, int type, struct list_head *ws) { - return __free_workspace(type, ws, false); + switch (type) { + case BTRFS_COMPRESS_NONE: return btrfs_put_workspace(fs_info, type, ws); + case BTRFS_COMPRESS_ZLIB: return btrfs_put_workspace(fs_info, type, ws); + case BTRFS_COMPRESS_LZO: return btrfs_put_workspace(fs_info, type, ws); + case BTRFS_COMPRESS_ZSTD: return zstd_put_workspace(fs_info, ws); + default: + /* + * This can't happen, the type is validated several times + * before we get here. + */ + BUG(); + } } /* - * cleanup function for module exit + * Adjust @level according to the limits of the compression algorithm or + * fallback to default */ -static void free_workspaces(void) +static int btrfs_compress_set_level(unsigned int type, int level) { - struct list_head *workspace; - int i; + const struct btrfs_compress_levels *levels = btrfs_compress_levels[type]; - while (!list_empty(&btrfs_heuristic_ws.idle_ws)) { - workspace = btrfs_heuristic_ws.idle_ws.next; - list_del(workspace); - free_heuristic_ws(workspace); - atomic_dec(&btrfs_heuristic_ws.total_ws); - } + if (level == 0) + level = levels->default_level; + else + level = clamp(level, levels->min_level, levels->max_level); - for (i = 0; i < BTRFS_COMPRESS_TYPES; i++) { - while (!list_empty(&btrfs_comp_ws[i].idle_ws)) { - workspace = btrfs_comp_ws[i].idle_ws.next; - list_del(workspace); - btrfs_compress_op[i]->free_workspace(workspace); - atomic_dec(&btrfs_comp_ws[i].total_ws); - } + return level; +} + +/* + * Check whether the @level is within the valid range for the given type. + */ +bool btrfs_compress_level_valid(unsigned int type, int level) +{ + const struct btrfs_compress_levels *levels = btrfs_compress_levels[type]; + + return levels->min_level <= level && level <= levels->max_level; +} + +/* Wrapper around find_get_page(), with extra error message. */ +int btrfs_compress_filemap_get_folio(struct address_space *mapping, u64 start, + struct folio **in_folio_ret) +{ + struct folio *in_folio; + + /* + * The compressed write path should have the folio locked already, thus + * we only need to grab one reference. + */ + in_folio = filemap_get_folio(mapping, start >> PAGE_SHIFT); + if (IS_ERR(in_folio)) { + struct btrfs_inode *inode = BTRFS_I(mapping->host); + + btrfs_crit(inode->root->fs_info, + "failed to get page cache, root %lld ino %llu file offset %llu", + btrfs_root_id(inode->root), btrfs_ino(inode), start); + return -ENOENT; } + *in_folio_ret = in_folio; + return 0; } /* @@ -1016,187 +1035,240 @@ static void free_workspaces(void) * - compression algo are 0-3 * - the level are bits 4-7 * - * @out_pages is an in/out parameter, holds maximum number of pages to allocate - * and returns number of actually allocated pages + * @out_folios is an in/out parameter, holds maximum number of folios to allocate + * and returns number of actually allocated folios * * @total_in is used to return the number of bytes actually read. It * may be smaller than the input length if we had to exit early because we - * ran out of room in the pages array or because we cross the + * ran out of room in the folios array or because we cross the * max_out threshold. * * @total_out is an in/out parameter, must be set to the input length and will * be also used to return the total number of compressed bytes - * - * @max_out tells us the max number of bytes that we're allowed to - * stuff into pages */ -int btrfs_compress_pages(unsigned int type_level, struct address_space *mapping, - u64 start, struct page **pages, - unsigned long *out_pages, - unsigned long *total_in, - unsigned long *total_out) +int btrfs_compress_folios(unsigned int type, int level, struct btrfs_inode *inode, + u64 start, struct folio **folios, unsigned long *out_folios, + unsigned long *total_in, unsigned long *total_out) { + struct btrfs_fs_info *fs_info = inode->root->fs_info; + const unsigned long orig_len = *total_out; struct list_head *workspace; int ret; - int type = type_level & 0xF; - - workspace = find_workspace(type); - btrfs_compress_op[type - 1]->set_level(workspace, type_level); - ret = btrfs_compress_op[type-1]->compress_pages(workspace, mapping, - start, pages, - out_pages, - total_in, total_out); - free_workspace(type, workspace); + level = btrfs_compress_set_level(type, level); + workspace = get_workspace(fs_info, type, level); + ret = compression_compress_pages(type, workspace, inode, start, folios, + out_folios, total_in, total_out); + /* The total read-in bytes should be no larger than the input. */ + ASSERT(*total_in <= orig_len); + put_workspace(fs_info, type, workspace); return ret; } -/* - * pages_in is an array of pages with compressed data. - * - * disk_start is the starting logical offset of this array in the file - * - * orig_bio contains the pages from the file that we want to decompress into - * - * srclen is the number of bytes in pages_in - * - * The basic idea is that we have a bio that was created by readpages. - * The pages in the bio are for the uncompressed data, and they may not - * be contiguous. They all correspond to the range of bytes covered by - * the compressed extent. - */ static int btrfs_decompress_bio(struct compressed_bio *cb) { + struct btrfs_fs_info *fs_info = cb_to_fs_info(cb); struct list_head *workspace; int ret; int type = cb->compress_type; - workspace = find_workspace(type); - ret = btrfs_compress_op[type - 1]->decompress_bio(workspace, cb); - free_workspace(type, workspace); + workspace = get_workspace(fs_info, type, 0); + ret = compression_decompress_bio(workspace, cb); + put_workspace(fs_info, type, workspace); + if (!ret) + zero_fill_bio(&cb->orig_bbio->bio); return ret; } /* * a less complex decompression routine. Our compressed data fits in a * single page, and we want to read a single page out of it. - * start_byte tells us the offset into the compressed data we're interested in + * dest_pgoff tells us the offset into the destination folio where we write the + * decompressed data. */ -int btrfs_decompress(int type, unsigned char *data_in, struct page *dest_page, - unsigned long start_byte, size_t srclen, size_t destlen) +int btrfs_decompress(int type, const u8 *data_in, struct folio *dest_folio, + unsigned long dest_pgoff, size_t srclen, size_t destlen) { + struct btrfs_fs_info *fs_info = folio_to_fs_info(dest_folio); struct list_head *workspace; + const u32 sectorsize = fs_info->sectorsize; int ret; - workspace = find_workspace(type); + /* + * The full destination folio range should not exceed the folio size. + * And the @destlen should not exceed sectorsize, as this is only called for + * inline file extents, which should not exceed sectorsize. + */ + ASSERT(dest_pgoff + destlen <= folio_size(dest_folio) && destlen <= sectorsize); + + workspace = get_workspace(fs_info, type, 0); + ret = compression_decompress(type, workspace, data_in, dest_folio, + dest_pgoff, srclen, destlen); + put_workspace(fs_info, type, workspace); - ret = btrfs_compress_op[type-1]->decompress(workspace, data_in, - dest_page, start_byte, - srclen, destlen); + return ret; +} + +int btrfs_alloc_compress_wsm(struct btrfs_fs_info *fs_info) +{ + int ret; - free_workspace(type, workspace); + ret = alloc_workspace_manager(fs_info, BTRFS_COMPRESS_NONE); + if (ret < 0) + goto error; + ret = alloc_workspace_manager(fs_info, BTRFS_COMPRESS_ZLIB); + if (ret < 0) + goto error; + ret = alloc_workspace_manager(fs_info, BTRFS_COMPRESS_LZO); + if (ret < 0) + goto error; + ret = zstd_alloc_workspace_manager(fs_info); + if (ret < 0) + goto error; + return 0; +error: + btrfs_free_compress_wsm(fs_info); return ret; } +void btrfs_free_compress_wsm(struct btrfs_fs_info *fs_info) +{ + free_workspace_manager(fs_info, BTRFS_COMPRESS_NONE); + free_workspace_manager(fs_info, BTRFS_COMPRESS_ZLIB); + free_workspace_manager(fs_info, BTRFS_COMPRESS_LZO); + zstd_free_workspace_manager(fs_info); +} + +int __init btrfs_init_compress(void) +{ + if (bioset_init(&btrfs_compressed_bioset, BIO_POOL_SIZE, + offsetof(struct compressed_bio, bbio.bio), + BIOSET_NEED_BVECS)) + return -ENOMEM; + + compr_pool.shrinker = shrinker_alloc(SHRINKER_NONSLAB, "btrfs-compr-pages"); + if (!compr_pool.shrinker) + return -ENOMEM; + + spin_lock_init(&compr_pool.lock); + INIT_LIST_HEAD(&compr_pool.list); + compr_pool.count = 0; + /* 128K / 4K = 32, for 8 threads is 256 pages. */ + compr_pool.thresh = BTRFS_MAX_COMPRESSED / PAGE_SIZE * 8; + compr_pool.shrinker->count_objects = btrfs_compr_pool_count; + compr_pool.shrinker->scan_objects = btrfs_compr_pool_scan; + compr_pool.shrinker->batch = 32; + compr_pool.shrinker->seeks = DEFAULT_SEEKS; + shrinker_register(compr_pool.shrinker); + + return 0; +} + void __cold btrfs_exit_compress(void) { - free_workspaces(); + /* For now scan drains all pages and does not touch the parameters. */ + btrfs_compr_pool_scan(NULL, NULL); + shrinker_free(compr_pool.shrinker); + + bioset_exit(&btrfs_compressed_bioset); } /* - * Copy uncompressed data from working buffer to pages. + * The bvec is a single page bvec from a bio that contains folios from a filemap. * - * buf_start is the byte offset we're of the start of our workspace buffer. + * Since the folio may be a large one, and if the bv_page is not a head page of + * a large folio, then page->index is unreliable. * - * total_out is the last byte of the buffer + * Thus we need this helper to grab the proper file offset. */ -int btrfs_decompress_buf2page(const char *buf, unsigned long buf_start, - unsigned long total_out, u64 disk_start, - struct bio *bio) +static u64 file_offset_from_bvec(const struct bio_vec *bvec) { - unsigned long buf_offset; - unsigned long current_buf_start; - unsigned long start_byte; - unsigned long prev_start_byte; - unsigned long working_bytes = total_out - buf_start; - unsigned long bytes; - char *kaddr; - struct bio_vec bvec = bio_iter_iovec(bio, bio->bi_iter); + const struct page *page = bvec->bv_page; + const struct folio *folio = page_folio(page); - /* - * start byte is the first byte of the page we're currently - * copying into relative to the start of the compressed data. - */ - start_byte = page_offset(bvec.bv_page) - disk_start; + return (page_pgoff(folio, page) << PAGE_SHIFT) + bvec->bv_offset; +} - /* we haven't yet hit data corresponding to this page */ - if (total_out <= start_byte) - return 1; +/* + * Copy decompressed data from working buffer to pages. + * + * @buf: The decompressed data buffer + * @buf_len: The decompressed data length + * @decompressed: Number of bytes that are already decompressed inside the + * compressed extent + * @cb: The compressed extent descriptor + * @orig_bio: The original bio that the caller wants to read for + * + * An easier to understand graph is like below: + * + * |<- orig_bio ->| |<- orig_bio->| + * |<------- full decompressed extent ----->| + * |<----------- @cb range ---->| + * | |<-- @buf_len -->| + * |<--- @decompressed --->| + * + * Note that, @cb can be a subpage of the full decompressed extent, but + * @cb->start always has the same as the orig_file_offset value of the full + * decompressed extent. + * + * When reading compressed extent, we have to read the full compressed extent, + * while @orig_bio may only want part of the range. + * Thus this function will ensure only data covered by @orig_bio will be copied + * to. + * + * Return 0 if we have copied all needed contents for @orig_bio. + * Return >0 if we need continue decompress. + */ +int btrfs_decompress_buf2page(const char *buf, u32 buf_len, + struct compressed_bio *cb, u32 decompressed) +{ + struct bio *orig_bio = &cb->orig_bbio->bio; + /* Offset inside the full decompressed extent */ + u32 cur_offset; + + cur_offset = decompressed; + /* The main loop to do the copy */ + while (cur_offset < decompressed + buf_len) { + struct bio_vec bvec; + size_t copy_len; + u32 copy_start; + /* Offset inside the full decompressed extent */ + u32 bvec_offset; + void *kaddr; + + bvec = bio_iter_iovec(orig_bio, orig_bio->bi_iter); + /* + * cb->start may underflow, but subtracting that value can still + * give us correct offset inside the full decompressed extent. + */ + bvec_offset = file_offset_from_bvec(&bvec) - cb->start; - /* - * the start of the data we care about is offset into - * the middle of our working buffer - */ - if (total_out > start_byte && buf_start < start_byte) { - buf_offset = start_byte - buf_start; - working_bytes -= buf_offset; - } else { - buf_offset = 0; - } - current_buf_start = buf_start; - - /* copy bytes from the working buffer into the pages */ - while (working_bytes > 0) { - bytes = min_t(unsigned long, bvec.bv_len, - PAGE_SIZE - buf_offset); - bytes = min(bytes, working_bytes); - - kaddr = kmap_atomic(bvec.bv_page); - memcpy(kaddr + bvec.bv_offset, buf + buf_offset, bytes); - kunmap_atomic(kaddr); - flush_dcache_page(bvec.bv_page); - - buf_offset += bytes; - working_bytes -= bytes; - current_buf_start += bytes; - - /* check if we need to pick another page */ - bio_advance(bio, bytes); - if (!bio->bi_iter.bi_size) - return 0; - bvec = bio_iter_iovec(bio, bio->bi_iter); - prev_start_byte = start_byte; - start_byte = page_offset(bvec.bv_page) - disk_start; + /* Haven't reached the bvec range, exit */ + if (decompressed + buf_len <= bvec_offset) + return 1; + + copy_start = max(cur_offset, bvec_offset); + copy_len = min(bvec_offset + bvec.bv_len, + decompressed + buf_len) - copy_start; + ASSERT(copy_len); /* - * We need to make sure we're only adjusting - * our offset into compression working buffer when - * we're switching pages. Otherwise we can incorrectly - * keep copying when we were actually done. + * Extra range check to ensure we didn't go beyond + * @buf + @buf_len. */ - if (start_byte != prev_start_byte) { - /* - * make sure our new page is covered by this - * working buffer - */ - if (total_out <= start_byte) - return 1; + ASSERT(copy_start - decompressed < buf_len); - /* - * the next page in the biovec might not be adjacent - * to the last page, but it might still be found - * inside this working buffer. bump our offset pointer - */ - if (total_out > start_byte && - current_buf_start < start_byte) { - buf_offset = start_byte - buf_start; - working_bytes = total_out - start_byte; - current_buf_start = buf_start + buf_offset; - } - } - } + kaddr = bvec_kmap_local(&bvec); + memcpy(kaddr, buf + copy_start - decompressed, copy_len); + kunmap_local(kaddr); + cur_offset += copy_len; + bio_advance(orig_bio, copy_len); + /* Finished the bio */ + if (!orig_bio->bi_iter.bi_size) + return 0; + } return 1; } @@ -1221,7 +1293,7 @@ int btrfs_decompress_buf2page(const char *buf, unsigned long buf_start, #define ENTROPY_LVL_HIGH (80) /* - * For increasead precision in shannon_entropy calculation, + * For increased precision in shannon_entropy calculation, * let's do pow(n, M) to save more digits after comma: * * - maximum int bit length is 64 @@ -1447,7 +1519,7 @@ static void heuristic_collect_sample(struct inode *inode, u64 start, u64 end, struct heuristic_ws *ws) { struct page *page; - u64 index, index_end; + pgoff_t index, index_end; u32 i, curr_sample_pos; u8 *in_data; @@ -1467,13 +1539,13 @@ static void heuristic_collect_sample(struct inode *inode, u64 start, u64 end, index_end = end >> PAGE_SHIFT; /* Don't miss unaligned end */ - if (!IS_ALIGNED(end, PAGE_SIZE)) + if (!PAGE_ALIGNED(end)) index_end++; curr_sample_pos = 0; while (index < index_end) { page = find_get_page(inode->i_mapping, index); - in_data = kmap(page); + in_data = kmap_local_page(page); /* Handle case where the start is not aligned to PAGE_SIZE */ i = start % PAGE_SIZE; while (i < PAGE_SIZE - SAMPLING_READ_SIZE) { @@ -1486,7 +1558,7 @@ static void heuristic_collect_sample(struct inode *inode, u64 start, u64 end, start += SAMPLING_INTERVAL; curr_sample_pos += SAMPLING_READ_SIZE; } - kunmap(page); + kunmap_local(in_data); put_page(page); index++; @@ -1498,11 +1570,6 @@ static void heuristic_collect_sample(struct inode *inode, u64 start, u64 end, /* * Compression heuristic. * - * For now is's a naive and optimistic 'return true', we'll extend the logic to - * quickly (compared to direct compression) detect data characteristics - * (compressible/uncompressible) to avoid wasting CPU time on uncompressible - * data. - * * The following types of analysis can be performed: * - detect mostly zero data * - detect data with low "byte set" size (text, etc) @@ -1510,9 +1577,10 @@ static void heuristic_collect_sample(struct inode *inode, u64 start, u64 end, * * Return non-zero if the compression should be done, 0 otherwise. */ -int btrfs_compress_heuristic(struct inode *inode, u64 start, u64 end) +int btrfs_compress_heuristic(struct btrfs_inode *inode, u64 start, u64 end) { - struct list_head *ws_list = __find_workspace(0, true); + struct btrfs_fs_info *fs_info = inode->root->fs_info; + struct list_head *ws_list = get_workspace(fs_info, 0, 0); struct heuristic_ws *ws; u32 i; u8 byte; @@ -1520,7 +1588,7 @@ int btrfs_compress_heuristic(struct inode *inode, u64 start, u64 end) ws = list_entry(ws_list, struct heuristic_ws, list); - heuristic_collect_sample(inode, start, end, ws); + heuristic_collect_sample(&inode->vfs_inode, start, end, ws); if (sample_repeated_patterns(ws)) { ret = 1; @@ -1581,18 +1649,34 @@ int btrfs_compress_heuristic(struct inode *inode, u64 start, u64 end) } out: - __free_workspace(0, ws_list, true); + put_workspace(fs_info, 0, ws_list); return ret; } -unsigned int btrfs_compress_str2level(const char *str) +/* + * Convert the compression suffix (eg. after "zlib" starting with ":") to level. + * + * If the resulting level exceeds the algo's supported levels, it will be clamped. + * + * Return <0 if no valid string can be found. + * Return 0 if everything is fine. + */ +int btrfs_compress_str2level(unsigned int type, const char *str, int *level_ret) { - if (strncmp(str, "zlib", 4) != 0) + int level = 0; + int ret; + + if (!type) { + *level_ret = btrfs_compress_set_level(type, level); return 0; + } - /* Accepted form: zlib:1 up to zlib:9 and nothing left after the number */ - if (str[4] == ':' && '1' <= str[5] && str[5] <= '9' && str[6] == 0) - return str[5] - '0'; + if (str[0] == ':') { + ret = kstrtoint(str + 1, 10, &level); + if (ret) + return ret; + } - return BTRFS_ZLIB_DEFAULT_LEVEL; + *level_ret = btrfs_compress_set_level(type, level); + return 0; } |