From: Omar Sandoval <osan...@fb.com> The implementation resembles direct I/O: we have to flush any ordered extents, invalidate the page cache, and do the io tree/delalloc/extent map/ordered extent dance. From there, we can reuse the compression code with a minor modification to distinguish the write from writeback. This also creates inline extents when possible.
Now that read and write are implemented, this also sets the FMODE_ENCODED_IO flag in btrfs_file_open(). Reviewed-by: Josef Bacik <jo...@toxicpanda.com> Signed-off-by: Omar Sandoval <osan...@fb.com> --- fs/btrfs/compression.c | 7 +- fs/btrfs/compression.h | 6 +- fs/btrfs/ctree.h | 2 + fs/btrfs/file.c | 38 +++++- fs/btrfs/inode.c | 259 +++++++++++++++++++++++++++++++++++++++- fs/btrfs/ordered-data.c | 12 +- fs/btrfs/ordered-data.h | 2 + 7 files changed, 314 insertions(+), 12 deletions(-) diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index d9d1d9e38fc5..4cfd03918ffc 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -336,7 +336,8 @@ static void end_compressed_bio_write(struct bio *bio) bio->bi_status == BLK_STS_OK); cb->compressed_pages[0]->mapping = NULL; - end_compressed_writeback(inode, cb); + if (cb->writeback) + end_compressed_writeback(inode, cb); /* note, our inode could be gone now */ /* @@ -372,7 +373,8 @@ blk_status_t btrfs_submit_compressed_write(struct btrfs_inode *inode, u64 start, struct page **compressed_pages, unsigned long nr_pages, unsigned int write_flags, - struct cgroup_subsys_state *blkcg_css) + struct cgroup_subsys_state *blkcg_css, + bool writeback) { struct btrfs_fs_info *fs_info = inode->root->fs_info; struct bio *bio = NULL; @@ -396,6 +398,7 @@ blk_status_t btrfs_submit_compressed_write(struct btrfs_inode *inode, u64 start, cb->mirror_num = 0; cb->compressed_pages = compressed_pages; cb->compressed_len = compressed_len; + cb->writeback = writeback; cb->orig_bio = NULL; cb->nr_pages = nr_pages; diff --git a/fs/btrfs/compression.h b/fs/btrfs/compression.h index 8001b700ea3a..f95cdc16f503 100644 --- a/fs/btrfs/compression.h +++ b/fs/btrfs/compression.h @@ -49,6 +49,9 @@ struct compressed_bio { /* the compression algorithm for this bio */ int compress_type; + /* Whether this is a write for writeback. */ + bool writeback; + /* number of compressed pages in the array */ unsigned long nr_pages; @@ -96,7 +99,8 @@ blk_status_t btrfs_submit_compressed_write(struct btrfs_inode *inode, u64 start, struct page **compressed_pages, unsigned long nr_pages, unsigned int write_flags, - struct cgroup_subsys_state *blkcg_css); + struct cgroup_subsys_state *blkcg_css, + bool writeback); blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, int mirror_num, unsigned long bio_flags); diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index d093f7a900d7..33a08ab5cb0e 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -3158,6 +3158,8 @@ int btrfs_writepage_cow_fixup(struct page *page, u64 start, u64 end); void btrfs_writepage_endio_finish_ordered(struct page *page, u64 start, u64 end, int uptodate); ssize_t btrfs_encoded_read(struct kiocb *iocb, struct iov_iter *iter); +ssize_t btrfs_do_encoded_write(struct kiocb *iocb, struct iov_iter *from, + struct encoded_iov *encoded); extern const struct dentry_operations btrfs_dentry_operations; extern const struct iomap_ops btrfs_dio_iomap_ops; diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 88eb4c5ddd52..dd7fec85fea1 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -3,6 +3,7 @@ * Copyright (C) 2007 Oracle. All rights reserved. */ +#include <linux/encoded_io.h> #include <linux/fs.h> #include <linux/pagemap.h> #include <linux/time.h> @@ -1993,6 +1994,32 @@ static ssize_t btrfs_direct_write(struct kiocb *iocb, struct iov_iter *from) return written ? written : err; } +static ssize_t btrfs_encoded_write(struct kiocb *iocb, struct iov_iter *from) +{ + struct file *file = iocb->ki_filp; + struct inode *inode = file_inode(file); + struct encoded_iov encoded; + ssize_t ret; + + ret = copy_encoded_iov_from_iter(&encoded, from); + if (ret) + return ret; + + btrfs_inode_lock(inode, 0); + ret = generic_encoded_write_checks(iocb, &encoded); + if (ret || encoded.len == 0) + goto out; + + ret = btrfs_write_check(iocb, from, encoded.len); + if (ret < 0) + goto out; + + ret = btrfs_do_encoded_write(iocb, from, &encoded); +out: + btrfs_inode_unlock(inode, 0); + return ret; +} + static ssize_t btrfs_file_write_iter(struct kiocb *iocb, struct iov_iter *from) { @@ -2009,14 +2036,17 @@ static ssize_t btrfs_file_write_iter(struct kiocb *iocb, if (test_bit(BTRFS_FS_STATE_ERROR, &inode->root->fs_info->fs_state)) return -EROFS; - if (!(iocb->ki_flags & IOCB_DIRECT) && - (iocb->ki_flags & IOCB_NOWAIT)) + if ((iocb->ki_flags & IOCB_NOWAIT) && + (!(iocb->ki_flags & IOCB_DIRECT) || + (iocb->ki_flags & IOCB_ENCODED))) return -EOPNOTSUPP; if (sync) atomic_inc(&inode->sync_writers); - if (iocb->ki_flags & IOCB_DIRECT) + if (iocb->ki_flags & IOCB_ENCODED) + num_written = btrfs_encoded_write(iocb, from); + else if (iocb->ki_flags & IOCB_DIRECT) num_written = btrfs_direct_write(iocb, from); else num_written = btrfs_buffered_write(iocb, from); @@ -3587,7 +3617,7 @@ static loff_t btrfs_file_llseek(struct file *file, loff_t offset, int whence) static int btrfs_file_open(struct inode *inode, struct file *filp) { - filp->f_mode |= FMODE_NOWAIT | FMODE_BUF_RASYNC; + filp->f_mode |= FMODE_NOWAIT | FMODE_BUF_RASYNC | FMODE_ENCODED_IO; return generic_file_open(inode, filp); } diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 913f1eba3a92..c2fe76f57bf5 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -935,7 +935,7 @@ static noinline void submit_compressed_extents(struct async_chunk *async_chunk) ins.offset, async_extent->pages, async_extent->nr_pages, async_chunk->write_flags, - async_chunk->blkcg_css)) { + async_chunk->blkcg_css, true)) { struct page *p = async_extent->pages[0]; const u64 start = async_extent->start; const u64 end = start + async_extent->ram_size - 1; @@ -2712,6 +2712,7 @@ static int insert_ordered_extent_file_extent(struct btrfs_trans_handle *trans, * except if the ordered extent was truncated. */ update_inode_bytes = test_bit(BTRFS_ORDERED_DIRECT, &oe->flags) || + test_bit(BTRFS_ORDERED_ENCODED, &oe->flags) || test_bit(BTRFS_ORDERED_TRUNCATED, &oe->flags); return insert_reserved_file_extent(trans, BTRFS_I(oe->inode), @@ -2746,7 +2747,8 @@ static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent) if (!test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags) && !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags) && - !test_bit(BTRFS_ORDERED_DIRECT, &ordered_extent->flags)) + !test_bit(BTRFS_ORDERED_DIRECT, &ordered_extent->flags) && + !test_bit(BTRFS_ORDERED_ENCODED, &ordered_extent->flags)) clear_bits |= EXTENT_DELALLOC_NEW; freespace_inode = btrfs_is_free_space_inode(inode); @@ -10478,6 +10480,259 @@ ssize_t btrfs_encoded_read(struct kiocb *iocb, struct iov_iter *iter) return ret; } +ssize_t btrfs_do_encoded_write(struct kiocb *iocb, struct iov_iter *from, + struct encoded_iov *encoded) +{ + struct inode *inode = file_inode(iocb->ki_filp); + struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); + struct btrfs_root *root = BTRFS_I(inode)->root; + struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; + struct extent_changeset *data_reserved = NULL; + struct extent_state *cached_state = NULL; + int compression; + size_t orig_count; + u64 start, end; + u64 num_bytes, ram_bytes, disk_num_bytes; + unsigned long nr_pages, i; + struct page **pages; + struct btrfs_key ins; + bool extent_reserved = false; + struct extent_map *em; + ssize_t ret; + + switch (encoded->compression) { + case ENCODED_IOV_COMPRESSION_BTRFS_ZLIB: + compression = BTRFS_COMPRESS_ZLIB; + break; + case ENCODED_IOV_COMPRESSION_BTRFS_ZSTD: + compression = BTRFS_COMPRESS_ZSTD; + break; + case ENCODED_IOV_COMPRESSION_BTRFS_LZO_4K: + case ENCODED_IOV_COMPRESSION_BTRFS_LZO_8K: + case ENCODED_IOV_COMPRESSION_BTRFS_LZO_16K: + case ENCODED_IOV_COMPRESSION_BTRFS_LZO_32K: + case ENCODED_IOV_COMPRESSION_BTRFS_LZO_64K: + /* The page size must match for LZO. */ + if (encoded->compression - + ENCODED_IOV_COMPRESSION_BTRFS_LZO_4K + 12 != PAGE_SHIFT) + return -EINVAL; + compression = BTRFS_COMPRESS_LZO; + break; + default: + return -EINVAL; + } + if (encoded->encryption != ENCODED_IOV_ENCRYPTION_NONE) + return -EINVAL; + + orig_count = iov_iter_count(from); + + /* The extent size must be sane. */ + if (encoded->unencoded_len > BTRFS_MAX_UNCOMPRESSED || + orig_count > BTRFS_MAX_COMPRESSED || orig_count == 0) + return -EINVAL; + + /* + * The compressed data must be smaller than the decompressed data. + * + * It's of course possible for data to compress to larger or the same + * size, but the buffered I/O path falls back to no compression for such + * data, and we don't want to break any assumptions by creating these + * extents. + * + * Note that this is less strict than the current check we have that the + * compressed data must be at least one sector smaller than the + * decompressed data. We only want to enforce the weaker requirement + * from old kernels that it is at least one byte smaller. + */ + if (orig_count >= encoded->unencoded_len) + return -EINVAL; + + /* The extent must start on a sector boundary. */ + start = iocb->ki_pos; + if (!IS_ALIGNED(start, fs_info->sectorsize)) + return -EINVAL; + + /* + * The extent must end on a sector boundary. However, we allow a write + * which ends at or extends i_size to have an unaligned length; we round + * up the extent size and set i_size to the unaligned end. + */ + if (start + encoded->len < inode->i_size && + !IS_ALIGNED(start + encoded->len, fs_info->sectorsize)) + return -EINVAL; + + /* Finally, the offset in the unencoded data must be sector-aligned. */ + if (!IS_ALIGNED(encoded->unencoded_offset, fs_info->sectorsize)) + return -EINVAL; + + num_bytes = ALIGN(encoded->len, fs_info->sectorsize); + ram_bytes = ALIGN(encoded->unencoded_len, fs_info->sectorsize); + end = start + num_bytes - 1; + + /* + * If the extent cannot be inline, the compressed data on disk must be + * sector-aligned. For convenience, we extend it with zeroes if it + * isn't. + */ + disk_num_bytes = ALIGN(orig_count, fs_info->sectorsize); + nr_pages = DIV_ROUND_UP(disk_num_bytes, PAGE_SIZE); + pages = kvcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL_ACCOUNT); + if (!pages) + return -ENOMEM; + for (i = 0; i < nr_pages; i++) { + size_t bytes = min_t(size_t, PAGE_SIZE, iov_iter_count(from)); + char *kaddr; + + pages[i] = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_HIGHMEM); + if (!pages[i]) { + ret = -ENOMEM; + goto out_pages; + } + kaddr = kmap(pages[i]); + if (copy_from_iter(kaddr, bytes, from) != bytes) { + kunmap(pages[i]); + ret = -EFAULT; + goto out_pages; + } + if (bytes < PAGE_SIZE) + memset(kaddr + bytes, 0, PAGE_SIZE - bytes); + kunmap(pages[i]); + } + + for (;;) { + struct btrfs_ordered_extent *ordered; + + ret = btrfs_wait_ordered_range(inode, start, num_bytes); + if (ret) + goto out_pages; + ret = invalidate_inode_pages2_range(inode->i_mapping, + start >> PAGE_SHIFT, + end >> PAGE_SHIFT); + if (ret) + goto out_pages; + lock_extent_bits(io_tree, start, end, &cached_state); + ordered = btrfs_lookup_ordered_range(BTRFS_I(inode), start, + num_bytes); + if (!ordered && + !filemap_range_has_page(inode->i_mapping, start, end)) + break; + if (ordered) + btrfs_put_ordered_extent(ordered); + unlock_extent_cached(io_tree, start, end, &cached_state); + cond_resched(); + } + + /* + * We don't use the higher-level delalloc space functions because our + * num_bytes and disk_num_bytes are different. + */ + ret = btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode), disk_num_bytes); + if (ret) + goto out_unlock; + ret = btrfs_qgroup_reserve_data(BTRFS_I(inode), &data_reserved, start, + num_bytes); + if (ret) + goto out_free_data_space; + ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode), num_bytes, + disk_num_bytes); + if (ret) + goto out_qgroup_free_data; + + /* Try an inline extent first. */ + if (start == 0 && encoded->unencoded_len == encoded->len && + encoded->unencoded_offset == 0) { + ret = cow_file_range_inline(BTRFS_I(inode), encoded->len, + orig_count, compression, pages, + true); + if (ret <= 0) { + if (ret == 0) + ret = orig_count; + goto out_delalloc_release; + } + } + + ret = btrfs_reserve_extent(root, disk_num_bytes, disk_num_bytes, + disk_num_bytes, 0, 0, &ins, 1, 1); + if (ret) + goto out_delalloc_release; + extent_reserved = true; + + em = create_io_em(BTRFS_I(inode), start, num_bytes, + start - encoded->unencoded_offset, ins.objectid, + ins.offset, ins.offset, ram_bytes, compression, + BTRFS_ORDERED_COMPRESSED); + if (IS_ERR(em)) { + ret = PTR_ERR(em); + goto out_free_reserved; + } + free_extent_map(em); + + ret = btrfs_add_ordered_extent(BTRFS_I(inode), start, num_bytes, + ram_bytes, ins.objectid, ins.offset, + encoded->unencoded_offset, + (1 << BTRFS_ORDERED_ENCODED) | + (1 << BTRFS_ORDERED_COMPRESSED), + compression); + if (ret) { + btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 0); + goto out_free_reserved; + } + btrfs_dec_block_group_reservations(fs_info, ins.objectid); + + if (start + encoded->len > inode->i_size) + i_size_write(inode, start + encoded->len); + + unlock_extent_cached(io_tree, start, end, &cached_state); + + btrfs_delalloc_release_extents(BTRFS_I(inode), num_bytes); + + if (btrfs_submit_compressed_write(BTRFS_I(inode), start, num_bytes, + ins.objectid, ins.offset, pages, + nr_pages, 0, NULL, false)) { + struct page *page = pages[0]; + + page->mapping = inode->i_mapping; + btrfs_writepage_endio_finish_ordered(page, start, end, 0); + page->mapping = NULL; + ret = -EIO; + goto out_pages; + } + ret = orig_count; + goto out; + +out_free_reserved: + btrfs_dec_block_group_reservations(fs_info, ins.objectid); + btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1); +out_delalloc_release: + btrfs_delalloc_release_extents(BTRFS_I(inode), num_bytes); + btrfs_delalloc_release_metadata(BTRFS_I(inode), disk_num_bytes, + ret < 0); +out_qgroup_free_data: + if (ret < 0) { + btrfs_qgroup_free_data(BTRFS_I(inode), data_reserved, start, + num_bytes); + } +out_free_data_space: + /* + * If btrfs_reserve_extent() succeeded, then we already decremented + * bytes_may_use. + */ + if (!extent_reserved) + btrfs_free_reserved_data_space_noquota(fs_info, disk_num_bytes); +out_unlock: + unlock_extent_cached(io_tree, start, end, &cached_state); +out_pages: + for (i = 0; i < nr_pages; i++) { + if (pages[i]) + __free_page(pages[i]); + } + kvfree(pages); +out: + if (ret >= 0) + iocb->ki_pos += encoded->len; + return ret; +} + #ifdef CONFIG_SWAP /* * Add an entry indicating a block group or device which is pinned by a diff --git a/fs/btrfs/ordered-data.c b/fs/btrfs/ordered-data.c index e11a517fab10..00329d82337e 100644 --- a/fs/btrfs/ordered-data.c +++ b/fs/btrfs/ordered-data.c @@ -472,9 +472,15 @@ void btrfs_remove_ordered_extent(struct btrfs_inode *btrfs_inode, spin_lock(&btrfs_inode->lock); btrfs_mod_outstanding_extents(btrfs_inode, -1); spin_unlock(&btrfs_inode->lock); - if (root != fs_info->tree_root) - btrfs_delalloc_release_metadata(btrfs_inode, entry->num_bytes, - false); + if (root != fs_info->tree_root) { + u64 release; + + if (test_bit(BTRFS_ORDERED_ENCODED, &entry->flags)) + release = entry->disk_num_bytes; + else + release = entry->num_bytes; + btrfs_delalloc_release_metadata(btrfs_inode, release, false); + } if (test_bit(BTRFS_ORDERED_DIRECT, &entry->flags)) percpu_counter_add_batch(&fs_info->dio_bytes, -entry->num_bytes, diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h index 8c8d6ed7a350..67c72485bd90 100644 --- a/fs/btrfs/ordered-data.h +++ b/fs/btrfs/ordered-data.h @@ -62,6 +62,8 @@ enum { BTRFS_ORDERED_LOGGED_CSUM, /* We wait for this extent to complete in the current transaction */ BTRFS_ORDERED_PENDING, + /* RWF_ENCODED I/O */ + BTRFS_ORDERED_ENCODED, }; struct btrfs_ordered_extent { -- 2.30.0