| // SPDX-License-Identifier: GPL-2.0 |
| /* |
| * Copyright (C) 2007 Oracle. All rights reserved. |
| */ |
| |
| #include <crypto/hash.h> |
| #include <linux/kernel.h> |
| #include <linux/bio.h> |
| #include <linux/blk-cgroup.h> |
| #include <linux/file.h> |
| #include <linux/fs.h> |
| #include <linux/pagemap.h> |
| #include <linux/highmem.h> |
| #include <linux/time.h> |
| #include <linux/init.h> |
| #include <linux/string.h> |
| #include <linux/backing-dev.h> |
| #include <linux/writeback.h> |
| #include <linux/compat.h> |
| #include <linux/xattr.h> |
| #include <linux/posix_acl.h> |
| #include <linux/falloc.h> |
| #include <linux/slab.h> |
| #include <linux/ratelimit.h> |
| #include <linux/btrfs.h> |
| #include <linux/blkdev.h> |
| #include <linux/posix_acl_xattr.h> |
| #include <linux/uio.h> |
| #include <linux/magic.h> |
| #include <linux/iversion.h> |
| #include <linux/swap.h> |
| #include <linux/migrate.h> |
| #include <linux/sched/mm.h> |
| #include <linux/iomap.h> |
| #include <asm/unaligned.h> |
| #include <linux/fsverity.h> |
| #include "misc.h" |
| #include "ctree.h" |
| #include "disk-io.h" |
| #include "transaction.h" |
| #include "btrfs_inode.h" |
| #include "print-tree.h" |
| #include "ordered-data.h" |
| #include "xattr.h" |
| #include "tree-log.h" |
| #include "volumes.h" |
| #include "compression.h" |
| #include "locking.h" |
| #include "free-space-cache.h" |
| #include "props.h" |
| #include "qgroup.h" |
| #include "delalloc-space.h" |
| #include "block-group.h" |
| #include "space-info.h" |
| #include "zoned.h" |
| #include "subpage.h" |
| |
| struct btrfs_iget_args { |
| u64 ino; |
| struct btrfs_root *root; |
| }; |
| |
| struct btrfs_dio_data { |
| u64 reserve; |
| loff_t length; |
| ssize_t submitted; |
| struct extent_changeset *data_reserved; |
| }; |
| |
| static const struct inode_operations btrfs_dir_inode_operations; |
| static const struct inode_operations btrfs_symlink_inode_operations; |
| static const struct inode_operations btrfs_special_inode_operations; |
| static const struct inode_operations btrfs_file_inode_operations; |
| static const struct address_space_operations btrfs_aops; |
| static const struct file_operations btrfs_dir_file_operations; |
| |
| static struct kmem_cache *btrfs_inode_cachep; |
| struct kmem_cache *btrfs_trans_handle_cachep; |
| struct kmem_cache *btrfs_path_cachep; |
| struct kmem_cache *btrfs_free_space_cachep; |
| struct kmem_cache *btrfs_free_space_bitmap_cachep; |
| |
| static int btrfs_setsize(struct inode *inode, struct iattr *attr); |
| static int btrfs_truncate(struct inode *inode, bool skip_writeback); |
| static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent); |
| static noinline int cow_file_range(struct btrfs_inode *inode, |
| struct page *locked_page, |
| u64 start, u64 end, int *page_started, |
| unsigned long *nr_written, int unlock); |
| static struct extent_map *create_io_em(struct btrfs_inode *inode, u64 start, |
| u64 len, u64 orig_start, u64 block_start, |
| u64 block_len, u64 orig_block_len, |
| u64 ram_bytes, int compress_type, |
| int type); |
| |
| static void __endio_write_update_ordered(struct btrfs_inode *inode, |
| const u64 offset, const u64 bytes, |
| const bool uptodate); |
| |
| /* |
| * btrfs_inode_lock - lock inode i_rwsem based on arguments passed |
| * |
| * ilock_flags can have the following bit set: |
| * |
| * BTRFS_ILOCK_SHARED - acquire a shared lock on the inode |
| * BTRFS_ILOCK_TRY - try to acquire the lock, if fails on first attempt |
| * return -EAGAIN |
| * BTRFS_ILOCK_MMAP - acquire a write lock on the i_mmap_lock |
| */ |
| int btrfs_inode_lock(struct inode *inode, unsigned int ilock_flags) |
| { |
| if (ilock_flags & BTRFS_ILOCK_SHARED) { |
| if (ilock_flags & BTRFS_ILOCK_TRY) { |
| if (!inode_trylock_shared(inode)) |
| return -EAGAIN; |
| else |
| return 0; |
| } |
| inode_lock_shared(inode); |
| } else { |
| if (ilock_flags & BTRFS_ILOCK_TRY) { |
| if (!inode_trylock(inode)) |
| return -EAGAIN; |
| else |
| return 0; |
| } |
| inode_lock(inode); |
| } |
| if (ilock_flags & BTRFS_ILOCK_MMAP) |
| down_write(&BTRFS_I(inode)->i_mmap_lock); |
| return 0; |
| } |
| |
| /* |
| * btrfs_inode_unlock - unock inode i_rwsem |
| * |
| * ilock_flags should contain the same bits set as passed to btrfs_inode_lock() |
| * to decide whether the lock acquired is shared or exclusive. |
| */ |
| void btrfs_inode_unlock(struct inode *inode, unsigned int ilock_flags) |
| { |
| if (ilock_flags & BTRFS_ILOCK_MMAP) |
| up_write(&BTRFS_I(inode)->i_mmap_lock); |
| if (ilock_flags & BTRFS_ILOCK_SHARED) |
| inode_unlock_shared(inode); |
| else |
| inode_unlock(inode); |
| } |
| |
| /* |
| * Cleanup all submitted ordered extents in specified range to handle errors |
| * from the btrfs_run_delalloc_range() callback. |
| * |
| * NOTE: caller must ensure that when an error happens, it can not call |
| * extent_clear_unlock_delalloc() to clear both the bits EXTENT_DO_ACCOUNTING |
| * and EXTENT_DELALLOC simultaneously, because that causes the reserved metadata |
| * to be released, which we want to happen only when finishing the ordered |
| * extent (btrfs_finish_ordered_io()). |
| */ |
| static inline void btrfs_cleanup_ordered_extents(struct btrfs_inode *inode, |
| struct page *locked_page, |
| u64 offset, u64 bytes) |
| { |
| unsigned long index = offset >> PAGE_SHIFT; |
| unsigned long end_index = (offset + bytes - 1) >> PAGE_SHIFT; |
| u64 page_start = page_offset(locked_page); |
| u64 page_end = page_start + PAGE_SIZE - 1; |
| |
| struct page *page; |
| |
| while (index <= end_index) { |
| /* |
| * For locked page, we will call end_extent_writepage() on it |
| * in run_delalloc_range() for the error handling. That |
| * end_extent_writepage() function will call |
| * btrfs_mark_ordered_io_finished() to clear page Ordered and |
| * run the ordered extent accounting. |
| * |
| * Here we can't just clear the Ordered bit, or |
| * btrfs_mark_ordered_io_finished() would skip the accounting |
| * for the page range, and the ordered extent will never finish. |
| */ |
| if (index == (page_offset(locked_page) >> PAGE_SHIFT)) { |
| index++; |
| continue; |
| } |
| page = find_get_page(inode->vfs_inode.i_mapping, index); |
| index++; |
| if (!page) |
| continue; |
| |
| /* |
| * Here we just clear all Ordered bits for every page in the |
| * range, then __endio_write_update_ordered() will handle |
| * the ordered extent accounting for the range. |
| */ |
| btrfs_page_clamp_clear_ordered(inode->root->fs_info, page, |
| offset, bytes); |
| put_page(page); |
| } |
| |
| /* The locked page covers the full range, nothing needs to be done */ |
| if (bytes + offset <= page_offset(locked_page) + PAGE_SIZE) |
| return; |
| /* |
| * In case this page belongs to the delalloc range being instantiated |
| * then skip it, since the first page of a range is going to be |
| * properly cleaned up by the caller of run_delalloc_range |
| */ |
| if (page_start >= offset && page_end <= (offset + bytes - 1)) { |
| bytes = offset + bytes - page_offset(locked_page) - PAGE_SIZE; |
| offset = page_offset(locked_page) + PAGE_SIZE; |
| } |
| |
| return __endio_write_update_ordered(inode, offset, bytes, false); |
| } |
| |
| static int btrfs_dirty_inode(struct inode *inode); |
| |
| static int btrfs_init_inode_security(struct btrfs_trans_handle *trans, |
| struct inode *inode, struct inode *dir, |
| const struct qstr *qstr) |
| { |
| int err; |
| |
| err = btrfs_init_acl(trans, inode, dir); |
| if (!err) |
| err = btrfs_xattr_security_init(trans, inode, dir, qstr); |
| return err; |
| } |
| |
| /* |
| * this does all the hard work for inserting an inline extent into |
| * the btree. The caller should have done a btrfs_drop_extents so that |
| * no overlapping inline items exist in the btree |
| */ |
| static int insert_inline_extent(struct btrfs_trans_handle *trans, |
| struct btrfs_path *path, bool extent_inserted, |
| struct btrfs_root *root, struct inode *inode, |
| u64 start, size_t size, size_t compressed_size, |
| int compress_type, |
| struct page **compressed_pages) |
| { |
| struct extent_buffer *leaf; |
| struct page *page = NULL; |
| char *kaddr; |
| unsigned long ptr; |
| struct btrfs_file_extent_item *ei; |
| int ret; |
| size_t cur_size = size; |
| unsigned long offset; |
| |
| ASSERT((compressed_size > 0 && compressed_pages) || |
| (compressed_size == 0 && !compressed_pages)); |
| |
| if (compressed_size && compressed_pages) |
| cur_size = compressed_size; |
| |
| if (!extent_inserted) { |
| struct btrfs_key key; |
| size_t datasize; |
| |
| key.objectid = btrfs_ino(BTRFS_I(inode)); |
| key.offset = start; |
| key.type = BTRFS_EXTENT_DATA_KEY; |
| |
| datasize = btrfs_file_extent_calc_inline_size(cur_size); |
| ret = btrfs_insert_empty_item(trans, root, path, &key, |
| datasize); |
| if (ret) |
| goto fail; |
| } |
| leaf = path->nodes[0]; |
| ei = btrfs_item_ptr(leaf, path->slots[0], |
| struct btrfs_file_extent_item); |
| btrfs_set_file_extent_generation(leaf, ei, trans->transid); |
| btrfs_set_file_extent_type(leaf, ei, BTRFS_FILE_EXTENT_INLINE); |
| btrfs_set_file_extent_encryption(leaf, ei, 0); |
| btrfs_set_file_extent_other_encoding(leaf, ei, 0); |
| btrfs_set_file_extent_ram_bytes(leaf, ei, size); |
| ptr = btrfs_file_extent_inline_start(ei); |
| |
| if (compress_type != BTRFS_COMPRESS_NONE) { |
| struct page *cpage; |
| int i = 0; |
| while (compressed_size > 0) { |
| cpage = compressed_pages[i]; |
| cur_size = min_t(unsigned long, compressed_size, |
| PAGE_SIZE); |
| |
| kaddr = kmap_atomic(cpage); |
| write_extent_buffer(leaf, kaddr, ptr, cur_size); |
| kunmap_atomic(kaddr); |
| |
| i++; |
| ptr += cur_size; |
| compressed_size -= cur_size; |
| } |
| btrfs_set_file_extent_compression(leaf, ei, |
| compress_type); |
| } else { |
| page = find_get_page(inode->i_mapping, |
| start >> PAGE_SHIFT); |
| btrfs_set_file_extent_compression(leaf, ei, 0); |
| kaddr = kmap_atomic(page); |
| offset = offset_in_page(start); |
| write_extent_buffer(leaf, kaddr + offset, ptr, size); |
| kunmap_atomic(kaddr); |
| put_page(page); |
| } |
| btrfs_mark_buffer_dirty(leaf); |
| btrfs_release_path(path); |
| |
| /* |
| * We align size to sectorsize for inline extents just for simplicity |
| * sake. |
| */ |
| size = ALIGN(size, root->fs_info->sectorsize); |
| ret = btrfs_inode_set_file_extent_range(BTRFS_I(inode), start, size); |
| if (ret) |
| goto fail; |
| |
| /* |
| * we're an inline extent, so nobody can |
| * extend the file past i_size without locking |
| * a page we already have locked. |
| * |
| * We must do any isize and inode updates |
| * before we unlock the pages. Otherwise we |
| * could end up racing with unlink. |
| */ |
| BTRFS_I(inode)->disk_i_size = inode->i_size; |
| fail: |
| return ret; |
| } |
| |
| |
| /* |
| * conditionally insert an inline extent into the file. This |
| * does the checks required to make sure the data is small enough |
| * to fit as an inline extent. |
| */ |
| static noinline int cow_file_range_inline(struct btrfs_inode *inode, u64 start, |
| u64 end, size_t compressed_size, |
| int compress_type, |
| struct page **compressed_pages) |
| { |
| struct btrfs_drop_extents_args drop_args = { 0 }; |
| struct btrfs_root *root = inode->root; |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| struct btrfs_trans_handle *trans; |
| u64 isize = i_size_read(&inode->vfs_inode); |
| u64 actual_end = min(end + 1, isize); |
| u64 inline_len = actual_end - start; |
| u64 aligned_end = ALIGN(end, fs_info->sectorsize); |
| u64 data_len = inline_len; |
| int ret; |
| struct btrfs_path *path; |
| |
| if (compressed_size) |
| data_len = compressed_size; |
| |
| if (start > 0 || |
| actual_end > fs_info->sectorsize || |
| data_len > BTRFS_MAX_INLINE_DATA_SIZE(fs_info) || |
| (!compressed_size && |
| (actual_end & (fs_info->sectorsize - 1)) == 0) || |
| end + 1 < isize || |
| data_len > fs_info->max_inline) { |
| return 1; |
| } |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) { |
| btrfs_free_path(path); |
| return PTR_ERR(trans); |
| } |
| trans->block_rsv = &inode->block_rsv; |
| |
| drop_args.path = path; |
| drop_args.start = start; |
| drop_args.end = aligned_end; |
| drop_args.drop_cache = true; |
| drop_args.replace_extent = true; |
| |
| if (compressed_size && compressed_pages) |
| drop_args.extent_item_size = btrfs_file_extent_calc_inline_size( |
| compressed_size); |
| else |
| drop_args.extent_item_size = btrfs_file_extent_calc_inline_size( |
| inline_len); |
| |
| ret = btrfs_drop_extents(trans, root, inode, &drop_args); |
| if (ret) { |
| btrfs_abort_transaction(trans, ret); |
| goto out; |
| } |
| |
| if (isize > actual_end) |
| inline_len = min_t(u64, isize, actual_end); |
| ret = insert_inline_extent(trans, path, drop_args.extent_inserted, |
| root, &inode->vfs_inode, start, |
| inline_len, compressed_size, |
| compress_type, compressed_pages); |
| if (ret && ret != -ENOSPC) { |
| btrfs_abort_transaction(trans, ret); |
| goto out; |
| } else if (ret == -ENOSPC) { |
| ret = 1; |
| goto out; |
| } |
| |
| btrfs_update_inode_bytes(inode, inline_len, drop_args.bytes_found); |
| ret = btrfs_update_inode(trans, root, inode); |
| if (ret && ret != -ENOSPC) { |
| btrfs_abort_transaction(trans, ret); |
| goto out; |
| } else if (ret == -ENOSPC) { |
| ret = 1; |
| goto out; |
| } |
| |
| set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &inode->runtime_flags); |
| out: |
| /* |
| * Don't forget to free the reserved space, as for inlined extent |
| * it won't count as data extent, free them directly here. |
| * And at reserve time, it's always aligned to page size, so |
| * just free one page here. |
| */ |
| btrfs_qgroup_free_data(inode, NULL, 0, PAGE_SIZE); |
| btrfs_free_path(path); |
| btrfs_end_transaction(trans); |
| return ret; |
| } |
| |
| struct async_extent { |
| u64 start; |
| u64 ram_size; |
| u64 compressed_size; |
| struct page **pages; |
| unsigned long nr_pages; |
| int compress_type; |
| struct list_head list; |
| }; |
| |
| struct async_chunk { |
| struct inode *inode; |
| struct page *locked_page; |
| u64 start; |
| u64 end; |
| unsigned int write_flags; |
| struct list_head extents; |
| struct cgroup_subsys_state *blkcg_css; |
| struct btrfs_work work; |
| struct async_cow *async_cow; |
| }; |
| |
| struct async_cow { |
| atomic_t num_chunks; |
| struct async_chunk chunks[]; |
| }; |
| |
| static noinline int add_async_extent(struct async_chunk *cow, |
| u64 start, u64 ram_size, |
| u64 compressed_size, |
| struct page **pages, |
| unsigned long nr_pages, |
| int compress_type) |
| { |
| struct async_extent *async_extent; |
| |
| async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS); |
| BUG_ON(!async_extent); /* -ENOMEM */ |
| async_extent->start = start; |
| async_extent->ram_size = ram_size; |
| async_extent->compressed_size = compressed_size; |
| async_extent->pages = pages; |
| async_extent->nr_pages = nr_pages; |
| async_extent->compress_type = compress_type; |
| list_add_tail(&async_extent->list, &cow->extents); |
| return 0; |
| } |
| |
| /* |
| * Check if the inode has flags compatible with compression |
| */ |
| static inline bool inode_can_compress(struct btrfs_inode *inode) |
| { |
| if (inode->flags & BTRFS_INODE_NODATACOW || |
| inode->flags & BTRFS_INODE_NODATASUM) |
| return false; |
| return true; |
| } |
| |
| /* |
| * Check if the inode needs to be submitted to compression, based on mount |
| * options, defragmentation, properties or heuristics. |
| */ |
| static inline int inode_need_compress(struct btrfs_inode *inode, u64 start, |
| u64 end) |
| { |
| struct btrfs_fs_info *fs_info = inode->root->fs_info; |
| |
| if (!inode_can_compress(inode)) { |
| WARN(IS_ENABLED(CONFIG_BTRFS_DEBUG), |
| KERN_ERR "BTRFS: unexpected compression for ino %llu\n", |
| btrfs_ino(inode)); |
| return 0; |
| } |
| /* |
| * Special check for subpage. |
| * |
| * We lock the full page then run each delalloc range in the page, thus |
| * for the following case, we will hit some subpage specific corner case: |
| * |
| * 0 32K 64K |
| * | |///////| |///////| |
| * \- A \- B |
| * |
| * In above case, both range A and range B will try to unlock the full |
| * page [0, 64K), causing the one finished later will have page |
| * unlocked already, triggering various page lock requirement BUG_ON()s. |
| * |
| * So here we add an artificial limit that subpage compression can only |
| * if the range is fully page aligned. |
| * |
| * In theory we only need to ensure the first page is fully covered, but |
| * the tailing partial page will be locked until the full compression |
| * finishes, delaying the write of other range. |
| * |
| * TODO: Make btrfs_run_delalloc_range() to lock all delalloc range |
| * first to prevent any submitted async extent to unlock the full page. |
| * By this, we can ensure for subpage case that only the last async_cow |
| * will unlock the full page. |
| */ |
| if (fs_info->sectorsize < PAGE_SIZE) { |
| if (!IS_ALIGNED(start, PAGE_SIZE) || |
| !IS_ALIGNED(end + 1, PAGE_SIZE)) |
| return 0; |
| } |
| |
| /* force compress */ |
| if (btrfs_test_opt(fs_info, FORCE_COMPRESS)) |
| return 1; |
| /* defrag ioctl */ |
| if (inode->defrag_compress) |
| return 1; |
| /* bad compression ratios */ |
| if (inode->flags & BTRFS_INODE_NOCOMPRESS) |
| return 0; |
| if (btrfs_test_opt(fs_info, COMPRESS) || |
| inode->flags & BTRFS_INODE_COMPRESS || |
| inode->prop_compress) |
| return btrfs_compress_heuristic(&inode->vfs_inode, start, end); |
| return 0; |
| } |
| |
| static inline void inode_should_defrag(struct btrfs_inode *inode, |
| u64 start, u64 end, u64 num_bytes, u64 small_write) |
| { |
| /* If this is a small write inside eof, kick off a defrag */ |
| if (num_bytes < small_write && |
| (start > 0 || end + 1 < inode->disk_i_size)) |
| btrfs_add_inode_defrag(NULL, inode); |
| } |
| |
| /* |
| * we create compressed extents in two phases. The first |
| * phase compresses a range of pages that have already been |
| * locked (both pages and state bits are locked). |
| * |
| * This is done inside an ordered work queue, and the compression |
| * is spread across many cpus. The actual IO submission is step |
| * two, and the ordered work queue takes care of making sure that |
| * happens in the same order things were put onto the queue by |
| * writepages and friends. |
| * |
| * If this code finds it can't get good compression, it puts an |
| * entry onto the work queue to write the uncompressed bytes. This |
| * makes sure that both compressed inodes and uncompressed inodes |
| * are written in the same order that the flusher thread sent them |
| * down. |
| */ |
| static noinline int compress_file_range(struct async_chunk *async_chunk) |
| { |
| struct inode *inode = async_chunk->inode; |
| struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); |
| u64 blocksize = fs_info->sectorsize; |
| u64 start = async_chunk->start; |
| u64 end = async_chunk->end; |
| u64 actual_end; |
| u64 i_size; |
| int ret = 0; |
| struct page **pages = NULL; |
| unsigned long nr_pages; |
| unsigned long total_compressed = 0; |
| unsigned long total_in = 0; |
| int i; |
| int will_compress; |
| int compress_type = fs_info->compress_type; |
| int compressed_extents = 0; |
| int redirty = 0; |
| |
| inode_should_defrag(BTRFS_I(inode), start, end, end - start + 1, |
| SZ_16K); |
| |
| /* |
| * We need to save i_size before now because it could change in between |
| * us evaluating the size and assigning it. This is because we lock and |
| * unlock the page in truncate and fallocate, and then modify the i_size |
| * later on. |
| * |
| * The barriers are to emulate READ_ONCE, remove that once i_size_read |
| * does that for us. |
| */ |
| barrier(); |
| i_size = i_size_read(inode); |
| barrier(); |
| actual_end = min_t(u64, i_size, end + 1); |
| again: |
| will_compress = 0; |
| nr_pages = (end >> PAGE_SHIFT) - (start >> PAGE_SHIFT) + 1; |
| BUILD_BUG_ON((BTRFS_MAX_COMPRESSED % PAGE_SIZE) != 0); |
| nr_pages = min_t(unsigned long, nr_pages, |
| BTRFS_MAX_COMPRESSED / PAGE_SIZE); |
| |
| /* |
| * we don't want to send crud past the end of i_size through |
| * compression, that's just a waste of CPU time. So, if the |
| * end of the file is before the start of our current |
| * requested range of bytes, we bail out to the uncompressed |
| * cleanup code that can deal with all of this. |
| * |
| * It isn't really the fastest way to fix things, but this is a |
| * very uncommon corner. |
| */ |
| if (actual_end <= start) |
| goto cleanup_and_bail_uncompressed; |
| |
| total_compressed = actual_end - start; |
| |
| /* |
| * Skip compression for a small file range(<=blocksize) that |
| * isn't an inline extent, since it doesn't save disk space at all. |
| */ |
| if (total_compressed <= blocksize && |
| (start > 0 || end + 1 < BTRFS_I(inode)->disk_i_size)) |
| goto cleanup_and_bail_uncompressed; |
| |
| /* |
| * For subpage case, we require full page alignment for the sector |
| * aligned range. |
| * Thus we must also check against @actual_end, not just @end. |
| */ |
| if (blocksize < PAGE_SIZE) { |
| if (!IS_ALIGNED(start, PAGE_SIZE) || |
| !IS_ALIGNED(round_up(actual_end, blocksize), PAGE_SIZE)) |
| goto cleanup_and_bail_uncompressed; |
| } |
| |
| total_compressed = min_t(unsigned long, total_compressed, |
| BTRFS_MAX_UNCOMPRESSED); |
| total_in = 0; |
| ret = 0; |
| |
| /* |
| * we do compression for mount -o compress and when the |
| * inode has not been flagged as nocompress. This flag can |
| * change at any time if we discover bad compression ratios. |
| */ |
| if (inode_need_compress(BTRFS_I(inode), start, end)) { |
| WARN_ON(pages); |
| pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS); |
| if (!pages) { |
| /* just bail out to the uncompressed code */ |
| nr_pages = 0; |
| goto cont; |
| } |
| |
| if (BTRFS_I(inode)->defrag_compress) |
| compress_type = BTRFS_I(inode)->defrag_compress; |
| else if (BTRFS_I(inode)->prop_compress) |
| compress_type = BTRFS_I(inode)->prop_compress; |
| |
| /* |
| * we need to call clear_page_dirty_for_io on each |
| * page in the range. Otherwise applications with the file |
| * mmap'd can wander in and change the page contents while |
| * we are compressing them. |
| * |
| * If the compression fails for any reason, we set the pages |
| * dirty again later on. |
| * |
| * Note that the remaining part is redirtied, the start pointer |
| * has moved, the end is the original one. |
| */ |
| if (!redirty) { |
| extent_range_clear_dirty_for_io(inode, start, end); |
| redirty = 1; |
| } |
| |
| /* Compression level is applied here and only here */ |
| ret = btrfs_compress_pages( |
| compress_type | (fs_info->compress_level << 4), |
| inode->i_mapping, start, |
| pages, |
| &nr_pages, |
| &total_in, |
| &total_compressed); |
| |
| if (!ret) { |
| unsigned long offset = offset_in_page(total_compressed); |
| struct page *page = pages[nr_pages - 1]; |
| |
| /* zero the tail end of the last page, we might be |
| * sending it down to disk |
| */ |
| if (offset) |
| memzero_page(page, offset, PAGE_SIZE - offset); |
| will_compress = 1; |
| } |
| } |
| cont: |
| /* |
| * Check cow_file_range() for why we don't even try to create inline |
| * extent for subpage case. |
| */ |
| if (start == 0 && fs_info->sectorsize == PAGE_SIZE) { |
| /* lets try to make an inline extent */ |
| if (ret || total_in < actual_end) { |
| /* we didn't compress the entire range, try |
| * to make an uncompressed inline extent. |
| */ |
| ret = cow_file_range_inline(BTRFS_I(inode), start, end, |
| 0, BTRFS_COMPRESS_NONE, |
| NULL); |
| } else { |
| /* try making a compressed inline extent */ |
| ret = cow_file_range_inline(BTRFS_I(inode), start, end, |
| total_compressed, |
| compress_type, pages); |
| } |
| if (ret <= 0) { |
| unsigned long clear_flags = EXTENT_DELALLOC | |
| EXTENT_DELALLOC_NEW | EXTENT_DEFRAG | |
| EXTENT_DO_ACCOUNTING; |
| unsigned long page_error_op; |
| |
| page_error_op = ret < 0 ? PAGE_SET_ERROR : 0; |
| |
| /* |
| * inline extent creation worked or returned error, |
| * we don't need to create any more async work items. |
| * Unlock and free up our temp pages. |
| * |
| * We use DO_ACCOUNTING here because we need the |
| * delalloc_release_metadata to be done _after_ we drop |
| * our outstanding extent for clearing delalloc for this |
| * range. |
| */ |
| extent_clear_unlock_delalloc(BTRFS_I(inode), start, end, |
| NULL, |
| clear_flags, |
| PAGE_UNLOCK | |
| PAGE_START_WRITEBACK | |
| page_error_op | |
| PAGE_END_WRITEBACK); |
| |
| /* |
| * Ensure we only free the compressed pages if we have |
| * them allocated, as we can still reach here with |
| * inode_need_compress() == false. |
| */ |
| if (pages) { |
| for (i = 0; i < nr_pages; i++) { |
| WARN_ON(pages[i]->mapping); |
| put_page(pages[i]); |
| } |
| kfree(pages); |
| } |
| return 0; |
| } |
| } |
| |
| if (will_compress) { |
| /* |
| * we aren't doing an inline extent round the compressed size |
| * up to a block size boundary so the allocator does sane |
| * things |
| */ |
| total_compressed = ALIGN(total_compressed, blocksize); |
| |
| /* |
| * one last check to make sure the compression is really a |
| * win, compare the page count read with the blocks on disk, |
| * compression must free at least one sector size |
| */ |
| total_in = round_up(total_in, fs_info->sectorsize); |
| if (total_compressed + blocksize <= total_in) { |
| compressed_extents++; |
| |
| /* |
| * The async work queues will take care of doing actual |
| * allocation on disk for these compressed pages, and |
| * will submit them to the elevator. |
| */ |
| add_async_extent(async_chunk, start, total_in, |
| total_compressed, pages, nr_pages, |
| compress_type); |
| |
| if (start + total_in < end) { |
| start += total_in; |
| pages = NULL; |
| cond_resched(); |
| goto again; |
| } |
| return compressed_extents; |
| } |
| } |
| if (pages) { |
| /* |
| * the compression code ran but failed to make things smaller, |
| * free any pages it allocated and our page pointer array |
| */ |
| for (i = 0; i < nr_pages; i++) { |
| WARN_ON(pages[i]->mapping); |
| put_page(pages[i]); |
| } |
| kfree(pages); |
| pages = NULL; |
| total_compressed = 0; |
| nr_pages = 0; |
| |
| /* flag the file so we don't compress in the future */ |
| if (!btrfs_test_opt(fs_info, FORCE_COMPRESS) && |
| !(BTRFS_I(inode)->prop_compress)) { |
| BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS; |
| } |
| } |
| cleanup_and_bail_uncompressed: |
| /* |
| * No compression, but we still need to write the pages in the file |
| * we've been given so far. redirty the locked page if it corresponds |
| * to our extent and set things up for the async work queue to run |
| * cow_file_range to do the normal delalloc dance. |
| */ |
| if (async_chunk->locked_page && |
| (page_offset(async_chunk->locked_page) >= start && |
| page_offset(async_chunk->locked_page)) <= end) { |
| __set_page_dirty_nobuffers(async_chunk->locked_page); |
| /* unlocked later on in the async handlers */ |
| } |
| |
| if (redirty) |
| extent_range_redirty_for_io(inode, start, end); |
| add_async_extent(async_chunk, start, end - start + 1, 0, NULL, 0, |
| BTRFS_COMPRESS_NONE); |
| compressed_extents++; |
| |
| return compressed_extents; |
| } |
| |
| static void free_async_extent_pages(struct async_extent *async_extent) |
| { |
| int i; |
| |
| if (!async_extent->pages) |
| return; |
| |
| for (i = 0; i < async_extent->nr_pages; i++) { |
| WARN_ON(async_extent->pages[i]->mapping); |
| put_page(async_extent->pages[i]); |
| } |
| kfree(async_extent->pages); |
| async_extent->nr_pages = 0; |
| async_extent->pages = NULL; |
| } |
| |
| static int submit_uncompressed_range(struct btrfs_inode *inode, |
| struct async_extent *async_extent, |
| struct page *locked_page) |
| { |
| u64 start = async_extent->start; |
| u64 end = async_extent->start + async_extent->ram_size - 1; |
| unsigned long nr_written = 0; |
| int page_started = 0; |
| int ret; |
| |
| /* |
| * Call cow_file_range() to run the delalloc range directly, since we |
| * won't go to NOCOW or async path again. |
| * |
| * Also we call cow_file_range() with @unlock_page == 0, so that we |
| * can directly submit them without interruption. |
| */ |
| ret = cow_file_range(inode, locked_page, start, end, &page_started, |
| &nr_written, 0); |
| /* Inline extent inserted, page gets unlocked and everything is done */ |
| if (page_started) { |
| ret = 0; |
| goto out; |
| } |
| if (ret < 0) { |
| if (locked_page) |
| unlock_page(locked_page); |
| goto out; |
| } |
| |
| ret = extent_write_locked_range(&inode->vfs_inode, start, end); |
| /* All pages will be unlocked, including @locked_page */ |
| out: |
| kfree(async_extent); |
| return ret; |
| } |
| |
| static int submit_one_async_extent(struct btrfs_inode *inode, |
| struct async_chunk *async_chunk, |
| struct async_extent *async_extent, |
| u64 *alloc_hint) |
| { |
| struct extent_io_tree *io_tree = &inode->io_tree; |
| struct btrfs_root *root = inode->root; |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| struct btrfs_key ins; |
| struct page *locked_page = NULL; |
| struct extent_map *em; |
| int ret = 0; |
| u64 start = async_extent->start; |
| u64 end = async_extent->start + async_extent->ram_size - 1; |
| |
| /* |
| * If async_chunk->locked_page is in the async_extent range, we need to |
| * handle it. |
| */ |
| if (async_chunk->locked_page) { |
| u64 locked_page_start = page_offset(async_chunk->locked_page); |
| u64 locked_page_end = locked_page_start + PAGE_SIZE - 1; |
| |
| if (!(start >= locked_page_end || end <= locked_page_start)) |
| locked_page = async_chunk->locked_page; |
| } |
| lock_extent(io_tree, start, end); |
| |
| /* We have fall back to uncompressed write */ |
| if (!async_extent->pages) |
| return submit_uncompressed_range(inode, async_extent, locked_page); |
| |
| ret = btrfs_reserve_extent(root, async_extent->ram_size, |
| async_extent->compressed_size, |
| async_extent->compressed_size, |
| 0, *alloc_hint, &ins, 1, 1); |
| if (ret) { |
| free_async_extent_pages(async_extent); |
| /* |
| * Here we used to try again by going back to non-compressed |
| * path for ENOSPC. But we can't reserve space even for |
| * compressed size, how could it work for uncompressed size |
| * which requires larger size? So here we directly go error |
| * path. |
| */ |
| goto out_free; |
| } |
| |
| /* Here we're doing allocation and writeback of the compressed pages */ |
| em = create_io_em(inode, start, |
| async_extent->ram_size, /* len */ |
| start, /* orig_start */ |
| ins.objectid, /* block_start */ |
| ins.offset, /* block_len */ |
| ins.offset, /* orig_block_len */ |
| async_extent->ram_size, /* ram_bytes */ |
| async_extent->compress_type, |
| BTRFS_ORDERED_COMPRESSED); |
| if (IS_ERR(em)) { |
| ret = PTR_ERR(em); |
| goto out_free_reserve; |
| } |
| free_extent_map(em); |
| |
| ret = btrfs_add_ordered_extent_compress(inode, start, /* file_offset */ |
| ins.objectid, /* disk_bytenr */ |
| async_extent->ram_size, /* num_bytes */ |
| ins.offset, /* disk_num_bytes */ |
| async_extent->compress_type); |
| if (ret) { |
| btrfs_drop_extent_cache(inode, start, end, 0); |
| goto out_free_reserve; |
| } |
| btrfs_dec_block_group_reservations(fs_info, ins.objectid); |
| |
| /* Clear dirty, set writeback and unlock the pages. */ |
| extent_clear_unlock_delalloc(inode, start, end, |
| NULL, EXTENT_LOCKED | EXTENT_DELALLOC, |
| PAGE_UNLOCK | PAGE_START_WRITEBACK); |
| if (btrfs_submit_compressed_write(inode, start, /* file_offset */ |
| async_extent->ram_size, /* num_bytes */ |
| ins.objectid, /* disk_bytenr */ |
| ins.offset, /* compressed_len */ |
| async_extent->pages, /* compressed_pages */ |
| async_extent->nr_pages, |
| async_chunk->write_flags, |
| async_chunk->blkcg_css)) { |
| const u64 start = async_extent->start; |
| const u64 end = start + async_extent->ram_size - 1; |
| |
| btrfs_writepage_endio_finish_ordered(inode, NULL, start, end, 0); |
| |
| extent_clear_unlock_delalloc(inode, start, end, NULL, 0, |
| PAGE_END_WRITEBACK | PAGE_SET_ERROR); |
| free_async_extent_pages(async_extent); |
| } |
| *alloc_hint = ins.objectid + ins.offset; |
| kfree(async_extent); |
| return ret; |
| |
| out_free_reserve: |
| btrfs_dec_block_group_reservations(fs_info, ins.objectid); |
| btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1); |
| out_free: |
| extent_clear_unlock_delalloc(inode, start, end, |
| NULL, EXTENT_LOCKED | EXTENT_DELALLOC | |
| EXTENT_DELALLOC_NEW | |
| EXTENT_DEFRAG | EXTENT_DO_ACCOUNTING, |
| PAGE_UNLOCK | PAGE_START_WRITEBACK | |
| PAGE_END_WRITEBACK | PAGE_SET_ERROR); |
| free_async_extent_pages(async_extent); |
| kfree(async_extent); |
| return ret; |
| } |
| |
| /* |
| * Phase two of compressed writeback. This is the ordered portion of the code, |
| * which only gets called in the order the work was queued. We walk all the |
| * async extents created by compress_file_range and send them down to the disk. |
| */ |
| static noinline void submit_compressed_extents(struct async_chunk *async_chunk) |
| { |
| struct btrfs_inode *inode = BTRFS_I(async_chunk->inode); |
| struct btrfs_fs_info *fs_info = inode->root->fs_info; |
| struct async_extent *async_extent; |
| u64 alloc_hint = 0; |
| int ret = 0; |
| |
| while (!list_empty(&async_chunk->extents)) { |
| u64 extent_start; |
| u64 ram_size; |
| |
| async_extent = list_entry(async_chunk->extents.next, |
| struct async_extent, list); |
| list_del(&async_extent->list); |
| extent_start = async_extent->start; |
| ram_size = async_extent->ram_size; |
| |
| ret = submit_one_async_extent(inode, async_chunk, async_extent, |
| &alloc_hint); |
| btrfs_debug(fs_info, |
| "async extent submission failed root=%lld inode=%llu start=%llu len=%llu ret=%d", |
| inode->root->root_key.objectid, |
| btrfs_ino(inode), extent_start, ram_size, ret); |
| } |
| } |
| |
| static u64 get_extent_allocation_hint(struct btrfs_inode *inode, u64 start, |
| u64 num_bytes) |
| { |
| struct extent_map_tree *em_tree = &inode->extent_tree; |
| struct extent_map *em; |
| u64 alloc_hint = 0; |
| |
| read_lock(&em_tree->lock); |
| em = search_extent_mapping(em_tree, start, num_bytes); |
| if (em) { |
| /* |
| * if block start isn't an actual block number then find the |
| * first block in this inode and use that as a hint. If that |
| * block is also bogus then just don't worry about it. |
| */ |
| if (em->block_start >= EXTENT_MAP_LAST_BYTE) { |
| free_extent_map(em); |
| em = search_extent_mapping(em_tree, 0, 0); |
| if (em && em->block_start < EXTENT_MAP_LAST_BYTE) |
| alloc_hint = em->block_start; |
| if (em) |
| free_extent_map(em); |
| } else { |
| alloc_hint = em->block_start; |
| free_extent_map(em); |
| } |
| } |
| read_unlock(&em_tree->lock); |
| |
| return alloc_hint; |
| } |
| |
| /* |
| * when extent_io.c finds a delayed allocation range in the file, |
| * the call backs end up in this code. The basic idea is to |
| * allocate extents on disk for the range, and create ordered data structs |
| * in ram to track those extents. |
| * |
| * locked_page is the page that writepage had locked already. We use |
| * it to make sure we don't do extra locks or unlocks. |
| * |
| * *page_started is set to one if we unlock locked_page and do everything |
| * required to start IO on it. It may be clean and already done with |
| * IO when we return. |
| */ |
| static noinline int cow_file_range(struct btrfs_inode *inode, |
| struct page *locked_page, |
| u64 start, u64 end, int *page_started, |
| unsigned long *nr_written, int unlock) |
| { |
| struct btrfs_root *root = inode->root; |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| u64 alloc_hint = 0; |
| u64 num_bytes; |
| unsigned long ram_size; |
| u64 cur_alloc_size = 0; |
| u64 min_alloc_size; |
| u64 blocksize = fs_info->sectorsize; |
| struct btrfs_key ins; |
| struct extent_map *em; |
| unsigned clear_bits; |
| unsigned long page_ops; |
| bool extent_reserved = false; |
| int ret = 0; |
| |
| if (btrfs_is_free_space_inode(inode)) { |
| WARN_ON_ONCE(1); |
| ret = -EINVAL; |
| goto out_unlock; |
| } |
| |
| num_bytes = ALIGN(end - start + 1, blocksize); |
| num_bytes = max(blocksize, num_bytes); |
| ASSERT(num_bytes <= btrfs_super_total_bytes(fs_info->super_copy)); |
| |
| inode_should_defrag(inode, start, end, num_bytes, SZ_64K); |
| |
| /* |
| * Due to the page size limit, for subpage we can only trigger the |
| * writeback for the dirty sectors of page, that means data writeback |
| * is doing more writeback than what we want. |
| * |
| * This is especially unexpected for some call sites like fallocate, |
| * where we only increase i_size after everything is done. |
| * This means we can trigger inline extent even if we didn't want to. |
| * So here we skip inline extent creation completely. |
| */ |
| if (start == 0 && fs_info->sectorsize == PAGE_SIZE) { |
| /* lets try to make an inline extent */ |
| ret = cow_file_range_inline(inode, start, end, 0, |
| BTRFS_COMPRESS_NONE, NULL); |
| if (ret == 0) { |
| /* |
| * We use DO_ACCOUNTING here because we need the |
| * delalloc_release_metadata to be run _after_ we drop |
| * our outstanding extent for clearing delalloc for this |
| * range. |
| */ |
| extent_clear_unlock_delalloc(inode, start, end, |
| locked_page, |
| EXTENT_LOCKED | EXTENT_DELALLOC | |
| EXTENT_DELALLOC_NEW | EXTENT_DEFRAG | |
| EXTENT_DO_ACCOUNTING, PAGE_UNLOCK | |
| PAGE_START_WRITEBACK | PAGE_END_WRITEBACK); |
| *nr_written = *nr_written + |
| (end - start + PAGE_SIZE) / PAGE_SIZE; |
| *page_started = 1; |
| /* |
| * locked_page is locked by the caller of |
| * writepage_delalloc(), not locked by |
| * __process_pages_contig(). |
| * |
| * We can't let __process_pages_contig() to unlock it, |
| * as it doesn't have any subpage::writers recorded. |
| * |
| * Here we manually unlock the page, since the caller |
| * can't use page_started to determine if it's an |
| * inline extent or a compressed extent. |
| */ |
| unlock_page(locked_page); |
| goto out; |
| } else if (ret < 0) { |
| goto out_unlock; |
| } |
| } |
| |
| alloc_hint = get_extent_allocation_hint(inode, start, num_bytes); |
| btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0); |
| |
| /* |
| * Relocation relies on the relocated extents to have exactly the same |
| * size as the original extents. Normally writeback for relocation data |
| * extents follows a NOCOW path because relocation preallocates the |
| * extents. However, due to an operation such as scrub turning a block |
| * group to RO mode, it may fallback to COW mode, so we must make sure |
| * an extent allocated during COW has exactly the requested size and can |
| * not be split into smaller extents, otherwise relocation breaks and |
| * fails during the stage where it updates the bytenr of file extent |
| * items. |
| */ |
| if (btrfs_is_data_reloc_root(root)) |
| min_alloc_size = num_bytes; |
| else |
| min_alloc_size = fs_info->sectorsize; |
| |
| while (num_bytes > 0) { |
| cur_alloc_size = num_bytes; |
| ret = btrfs_reserve_extent(root, cur_alloc_size, cur_alloc_size, |
| min_alloc_size, 0, alloc_hint, |
| &ins, 1, 1); |
| if (ret < 0) |
| goto out_unlock; |
| cur_alloc_size = ins.offset; |
| extent_reserved = true; |
| |
| ram_size = ins.offset; |
| em = create_io_em(inode, start, ins.offset, /* len */ |
| start, /* orig_start */ |
| ins.objectid, /* block_start */ |
| ins.offset, /* block_len */ |
| ins.offset, /* orig_block_len */ |
| ram_size, /* ram_bytes */ |
| BTRFS_COMPRESS_NONE, /* compress_type */ |
| BTRFS_ORDERED_REGULAR /* type */); |
| if (IS_ERR(em)) { |
| ret = PTR_ERR(em); |
| goto out_reserve; |
| } |
| free_extent_map(em); |
| |
| ret = btrfs_add_ordered_extent(inode, start, ins.objectid, |
| ram_size, cur_alloc_size, |
| BTRFS_ORDERED_REGULAR); |
| if (ret) |
| goto out_drop_extent_cache; |
| |
| if (btrfs_is_data_reloc_root(root)) { |
| ret = btrfs_reloc_clone_csums(inode, start, |
| cur_alloc_size); |
| /* |
| * Only drop cache here, and process as normal. |
| * |
| * We must not allow extent_clear_unlock_delalloc() |
| * at out_unlock label to free meta of this ordered |
| * extent, as its meta should be freed by |
| * btrfs_finish_ordered_io(). |
| * |
| * So we must continue until @start is increased to |
| * skip current ordered extent. |
| */ |
| if (ret) |
| btrfs_drop_extent_cache(inode, start, |
| start + ram_size - 1, 0); |
| } |
| |
| btrfs_dec_block_group_reservations(fs_info, ins.objectid); |
| |
| /* |
| * We're not doing compressed IO, don't unlock the first page |
| * (which the caller expects to stay locked), don't clear any |
| * dirty bits and don't set any writeback bits |
| * |
| * Do set the Ordered (Private2) bit so we know this page was |
| * properly setup for writepage. |
| */ |
| page_ops = unlock ? PAGE_UNLOCK : 0; |
| page_ops |= PAGE_SET_ORDERED; |
| |
| extent_clear_unlock_delalloc(inode, start, start + ram_size - 1, |
| locked_page, |
| EXTENT_LOCKED | EXTENT_DELALLOC, |
| page_ops); |
| if (num_bytes < cur_alloc_size) |
| num_bytes = 0; |
| else |
| num_bytes -= cur_alloc_size; |
| alloc_hint = ins.objectid + ins.offset; |
| start += cur_alloc_size; |
| extent_reserved = false; |
| |
| /* |
| * btrfs_reloc_clone_csums() error, since start is increased |
| * extent_clear_unlock_delalloc() at out_unlock label won't |
| * free metadata of current ordered extent, we're OK to exit. |
| */ |
| if (ret) |
| goto out_unlock; |
| } |
| out: |
| return ret; |
| |
| out_drop_extent_cache: |
| btrfs_drop_extent_cache(inode, start, start + ram_size - 1, 0); |
| out_reserve: |
| btrfs_dec_block_group_reservations(fs_info, ins.objectid); |
| btrfs_free_reserved_extent(fs_info, ins.objectid, ins.offset, 1); |
| out_unlock: |
| clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC | EXTENT_DELALLOC_NEW | |
| EXTENT_DEFRAG | EXTENT_CLEAR_META_RESV; |
| page_ops = PAGE_UNLOCK | PAGE_START_WRITEBACK | PAGE_END_WRITEBACK; |
| /* |
| * If we reserved an extent for our delalloc range (or a subrange) and |
| * failed to create the respective ordered extent, then it means that |
| * when we reserved the extent we decremented the extent's size from |
| * the data space_info's bytes_may_use counter and incremented the |
| * space_info's bytes_reserved counter by the same amount. We must make |
| * sure extent_clear_unlock_delalloc() does not try to decrement again |
| * the data space_info's bytes_may_use counter, therefore we do not pass |
| * it the flag EXTENT_CLEAR_DATA_RESV. |
| */ |
| if (extent_reserved) { |
| extent_clear_unlock_delalloc(inode, start, |
| start + cur_alloc_size - 1, |
| locked_page, |
| clear_bits, |
| page_ops); |
| start += cur_alloc_size; |
| if (start >= end) |
| goto out; |
| } |
| extent_clear_unlock_delalloc(inode, start, end, locked_page, |
| clear_bits | EXTENT_CLEAR_DATA_RESV, |
| page_ops); |
| goto out; |
| } |
| |
| /* |
| * work queue call back to started compression on a file and pages |
| */ |
| static noinline void async_cow_start(struct btrfs_work *work) |
| { |
| struct async_chunk *async_chunk; |
| int compressed_extents; |
| |
| async_chunk = container_of(work, struct async_chunk, work); |
| |
| compressed_extents = compress_file_range(async_chunk); |
| if (compressed_extents == 0) { |
| btrfs_add_delayed_iput(async_chunk->inode); |
| async_chunk->inode = NULL; |
| } |
| } |
| |
| /* |
| * work queue call back to submit previously compressed pages |
| */ |
| static noinline void async_cow_submit(struct btrfs_work *work) |
| { |
| struct async_chunk *async_chunk = container_of(work, struct async_chunk, |
| work); |
| struct btrfs_fs_info *fs_info = btrfs_work_owner(work); |
| unsigned long nr_pages; |
| |
| nr_pages = (async_chunk->end - async_chunk->start + PAGE_SIZE) >> |
| PAGE_SHIFT; |
| |
| /* |
| * ->inode could be NULL if async_chunk_start has failed to compress, |
| * in which case we don't have anything to submit, yet we need to |
| * always adjust ->async_delalloc_pages as its paired with the init |
| * happening in cow_file_range_async |
| */ |
| if (async_chunk->inode) |
| submit_compressed_extents(async_chunk); |
| |
| /* atomic_sub_return implies a barrier */ |
| if (atomic_sub_return(nr_pages, &fs_info->async_delalloc_pages) < |
| 5 * SZ_1M) |
| cond_wake_up_nomb(&fs_info->async_submit_wait); |
| } |
| |
| static noinline void async_cow_free(struct btrfs_work *work) |
| { |
| struct async_chunk *async_chunk; |
| struct async_cow *async_cow; |
| |
| async_chunk = container_of(work, struct async_chunk, work); |
| if (async_chunk->inode) |
| btrfs_add_delayed_iput(async_chunk->inode); |
| if (async_chunk->blkcg_css) |
| css_put(async_chunk->blkcg_css); |
| |
| async_cow = async_chunk->async_cow; |
| if (atomic_dec_and_test(&async_cow->num_chunks)) |
| kvfree(async_cow); |
| } |
| |
| static int cow_file_range_async(struct btrfs_inode *inode, |
| struct writeback_control *wbc, |
| struct page *locked_page, |
| u64 start, u64 end, int *page_started, |
| unsigned long *nr_written) |
| { |
| struct btrfs_fs_info *fs_info = inode->root->fs_info; |
| struct cgroup_subsys_state *blkcg_css = wbc_blkcg_css(wbc); |
| struct async_cow *ctx; |
| struct async_chunk *async_chunk; |
| unsigned long nr_pages; |
| u64 cur_end; |
| u64 num_chunks = DIV_ROUND_UP(end - start, SZ_512K); |
| int i; |
| bool should_compress; |
| unsigned nofs_flag; |
| const unsigned int write_flags = wbc_to_write_flags(wbc); |
| |
| unlock_extent(&inode->io_tree, start, end); |
| |
| if (inode->flags & BTRFS_INODE_NOCOMPRESS && |
| !btrfs_test_opt(fs_info, FORCE_COMPRESS)) { |
| num_chunks = 1; |
| should_compress = false; |
| } else { |
| should_compress = true; |
| } |
| |
| nofs_flag = memalloc_nofs_save(); |
| ctx = kvmalloc(struct_size(ctx, chunks, num_chunks), GFP_KERNEL); |
| memalloc_nofs_restore(nofs_flag); |
| |
| if (!ctx) { |
| unsigned clear_bits = EXTENT_LOCKED | EXTENT_DELALLOC | |
| EXTENT_DELALLOC_NEW | EXTENT_DEFRAG | |
| EXTENT_DO_ACCOUNTING; |
| unsigned long page_ops = PAGE_UNLOCK | PAGE_START_WRITEBACK | |
| PAGE_END_WRITEBACK | PAGE_SET_ERROR; |
| |
| extent_clear_unlock_delalloc(inode, start, end, locked_page, |
| clear_bits, page_ops); |
| return -ENOMEM; |
| } |
| |
| async_chunk = ctx->chunks; |
| atomic_set(&ctx->num_chunks, num_chunks); |
| |
| for (i = 0; i < num_chunks; i++) { |
| if (should_compress) |
| cur_end = min(end, start + SZ_512K - 1); |
| else |
| cur_end = end; |
| |
| /* |
| * igrab is called higher up in the call chain, take only the |
| * lightweight reference for the callback lifetime |
| */ |
| ihold(&inode->vfs_inode); |
| async_chunk[i].async_cow = ctx; |
| async_chunk[i].inode = &inode->vfs_inode; |
| async_chunk[i].start = start; |
| async_chunk[i].end = cur_end; |
| async_chunk[i].write_flags = write_flags; |
| INIT_LIST_HEAD(&async_chunk[i].extents); |
| |
| /* |
| * The locked_page comes all the way from writepage and its |
| * the original page we were actually given. As we spread |
| * this large delalloc region across multiple async_chunk |
| * structs, only the first struct needs a pointer to locked_page |
| * |
| * This way we don't need racey decisions about who is supposed |
| * to unlock it. |
| */ |
| if (locked_page) { |
| /* |
| * Depending on the compressibility, the pages might or |
| * might not go through async. We want all of them to |
| * be accounted against wbc once. Let's do it here |
| * before the paths diverge. wbc accounting is used |
| * only for foreign writeback detection and doesn't |
| * need full accuracy. Just account the whole thing |
| * against the first page. |
| */ |
| wbc_account_cgroup_owner(wbc, locked_page, |
| cur_end - start); |
| async_chunk[i].locked_page = locked_page; |
| locked_page = NULL; |
| } else { |
| async_chunk[i].locked_page = NULL; |
| } |
| |
| if (blkcg_css != blkcg_root_css) { |
| css_get(blkcg_css); |
| async_chunk[i].blkcg_css = blkcg_css; |
| } else { |
| async_chunk[i].blkcg_css = NULL; |
| } |
| |
| btrfs_init_work(&async_chunk[i].work, async_cow_start, |
| async_cow_submit, async_cow_free); |
| |
| nr_pages = DIV_ROUND_UP(cur_end - start, PAGE_SIZE); |
| atomic_add(nr_pages, &fs_info->async_delalloc_pages); |
| |
| btrfs_queue_work(fs_info->delalloc_workers, &async_chunk[i].work); |
| |
| *nr_written += nr_pages; |
| start = cur_end + 1; |
| } |
| *page_started = 1; |
| return 0; |
| } |
| |
| static noinline int run_delalloc_zoned(struct btrfs_inode *inode, |
| struct page *locked_page, u64 start, |
| u64 end, int *page_started, |
| unsigned long *nr_written) |
| { |
| int ret; |
| |
| ret = cow_file_range(inode, locked_page, start, end, page_started, |
| nr_written, 0); |
| if (ret) |
| return ret; |
| |
| if (*page_started) |
| return 0; |
| |
| __set_page_dirty_nobuffers(locked_page); |
| account_page_redirty(locked_page); |
| extent_write_locked_range(&inode->vfs_inode, start, end); |
| *page_started = 1; |
| |
| return 0; |
| } |
| |
| static noinline int csum_exist_in_range(struct btrfs_fs_info *fs_info, |
| u64 bytenr, u64 num_bytes) |
| { |
| int ret; |
| struct btrfs_ordered_sum *sums; |
| LIST_HEAD(list); |
| |
| ret = btrfs_lookup_csums_range(fs_info->csum_root, bytenr, |
| bytenr + num_bytes - 1, &list, 0); |
| if (ret == 0 && list_empty(&list)) |
| return 0; |
| |
| while (!list_empty(&list)) { |
| sums = list_entry(list.next, struct btrfs_ordered_sum, list); |
| list_del(&sums->list); |
| kfree(sums); |
| } |
| if (ret < 0) |
| return ret; |
| return 1; |
| } |
| |
| static int fallback_to_cow(struct btrfs_inode *inode, struct page *locked_page, |
| const u64 start, const u64 end, |
| int *page_started, unsigned long *nr_written) |
| { |
| const bool is_space_ino = btrfs_is_free_space_inode(inode); |
| const bool is_reloc_ino = btrfs_is_data_reloc_root(inode->root); |
| const u64 range_bytes = end + 1 - start; |
| struct extent_io_tree *io_tree = &inode->io_tree; |
| u64 range_start = start; |
| u64 count; |
| |
| /* |
| * If EXTENT_NORESERVE is set it means that when the buffered write was |
| * made we had not enough available data space and therefore we did not |
| * reserve data space for it, since we though we could do NOCOW for the |
| * respective file range (either there is prealloc extent or the inode |
| * has the NOCOW bit set). |
| * |
| * However when we need to fallback to COW mode (because for example the |
| * block group for the corresponding extent was turned to RO mode by a |
| * scrub or relocation) we need to do the following: |
| * |
| * 1) We increment the bytes_may_use counter of the data space info. |
| * If COW succeeds, it allocates a new data extent and after doing |
| * that it decrements the space info's bytes_may_use counter and |
| * increments its bytes_reserved counter by the same amount (we do |
| * this at btrfs_add_reserved_bytes()). So we need to increment the |
| * bytes_may_use counter to compensate (when space is reserved at |
| * buffered write time, the bytes_may_use counter is incremented); |
| * |
| * 2) We clear the EXTENT_NORESERVE bit from the range. We do this so |
| * that if the COW path fails for any reason, it decrements (through |
| * extent_clear_unlock_delalloc()) the bytes_may_use counter of the |
| * data space info, which we incremented in the step above. |
| * |
| * If we need to fallback to cow and the inode corresponds to a free |
| * space cache inode or an inode of the data relocation tree, we must |
| * also increment bytes_may_use of the data space_info for the same |
| * reason. Space caches and relocated data extents always get a prealloc |
| * extent for them, however scrub or balance may have set the block |
| * group that contains that extent to RO mode and therefore force COW |
| * when starting writeback. |
| */ |
| count = count_range_bits(io_tree, &range_start, end, range_bytes, |
| EXTENT_NORESERVE, 0); |
| if (count > 0 || is_space_ino || is_reloc_ino) { |
| u64 bytes = count; |
| struct btrfs_fs_info *fs_info = inode->root->fs_info; |
| struct btrfs_space_info *sinfo = fs_info->data_sinfo; |
| |
| if (is_space_ino || is_reloc_ino) |
| bytes = range_bytes; |
| |
| spin_lock(&sinfo->lock); |
| btrfs_space_info_update_bytes_may_use(fs_info, sinfo, bytes); |
| spin_unlock(&sinfo->lock); |
| |
| if (count > 0) |
| clear_extent_bit(io_tree, start, end, EXTENT_NORESERVE, |
| 0, 0, NULL); |
| } |
| |
| return cow_file_range(inode, locked_page, start, end, page_started, |
| nr_written, 1); |
| } |
| |
| /* |
| * when nowcow writeback call back. This checks for snapshots or COW copies |
| * of the extents that exist in the file, and COWs the file as required. |
| * |
| * If no cow copies or snapshots exist, we write directly to the existing |
| * blocks on disk |
| */ |
| static noinline int run_delalloc_nocow(struct btrfs_inode *inode, |
| struct page *locked_page, |
| const u64 start, const u64 end, |
| int *page_started, |
| unsigned long *nr_written) |
| { |
| struct btrfs_fs_info *fs_info = inode->root->fs_info; |
| struct btrfs_root *root = inode->root; |
| struct btrfs_path *path; |
| u64 cow_start = (u64)-1; |
| u64 cur_offset = start; |
| int ret; |
| bool check_prev = true; |
| const bool freespace_inode = btrfs_is_free_space_inode(inode); |
| u64 ino = btrfs_ino(inode); |
| bool nocow = false; |
| u64 disk_bytenr = 0; |
| const bool force = inode->flags & BTRFS_INODE_NODATACOW; |
| |
| path = btrfs_alloc_path(); |
| if (!path) { |
| extent_clear_unlock_delalloc(inode, start, end, locked_page, |
| EXTENT_LOCKED | EXTENT_DELALLOC | |
| EXTENT_DO_ACCOUNTING | |
| EXTENT_DEFRAG, PAGE_UNLOCK | |
| PAGE_START_WRITEBACK | |
| PAGE_END_WRITEBACK); |
| return -ENOMEM; |
| } |
| |
| while (1) { |
| struct btrfs_key found_key; |
| struct btrfs_file_extent_item *fi; |
| struct extent_buffer *leaf; |
| u64 extent_end; |
| u64 extent_offset; |
| u64 num_bytes = 0; |
| u64 disk_num_bytes; |
| u64 ram_bytes; |
| int extent_type; |
| |
| nocow = false; |
| |
| ret = btrfs_lookup_file_extent(NULL, root, path, ino, |
| cur_offset, 0); |
| if (ret < 0) |
| goto error; |
| |
| /* |
| * If there is no extent for our range when doing the initial |
| * search, then go back to the previous slot as it will be the |
| * one containing the search offset |
| */ |
| if (ret > 0 && path->slots[0] > 0 && check_prev) { |
| leaf = path->nodes[0]; |
| btrfs_item_key_to_cpu(leaf, &found_key, |
| path->slots[0] - 1); |
| if (found_key.objectid == ino && |
| found_key.type == BTRFS_EXTENT_DATA_KEY) |
| path->slots[0]--; |
| } |
| check_prev = false; |
| next_slot: |
| /* Go to next leaf if we have exhausted the current one */ |
| leaf = path->nodes[0]; |
| if (path->slots[0] >= btrfs_header_nritems(leaf)) { |
| ret = btrfs_next_leaf(root, path); |
| if (ret < 0) { |
| if (cow_start != (u64)-1) |
| cur_offset = cow_start; |
| goto error; |
| } |
| if (ret > 0) |
| break; |
| leaf = path->nodes[0]; |
| } |
| |
| btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); |
| |
| /* Didn't find anything for our INO */ |
| if (found_key.objectid > ino) |
| break; |
| /* |
| * Keep searching until we find an EXTENT_ITEM or there are no |
| * more extents for this inode |
| */ |
| if (WARN_ON_ONCE(found_key.objectid < ino) || |
| found_key.type < BTRFS_EXTENT_DATA_KEY) { |
| path->slots[0]++; |
| goto next_slot; |
| } |
| |
| /* Found key is not EXTENT_DATA_KEY or starts after req range */ |
| if (found_key.type > BTRFS_EXTENT_DATA_KEY || |
| found_key.offset > end) |
| break; |
| |
| /* |
| * If the found extent starts after requested offset, then |
| * adjust extent_end to be right before this extent begins |
| */ |
| if (found_key.offset > cur_offset) { |
| extent_end = found_key.offset; |
| extent_type = 0; |
| goto out_check; |
| } |
| |
| /* |
| * Found extent which begins before our range and potentially |
| * intersect it |
| */ |
| fi = btrfs_item_ptr(leaf, path->slots[0], |
| struct btrfs_file_extent_item); |
| extent_type = btrfs_file_extent_type(leaf, fi); |
| |
| ram_bytes = btrfs_file_extent_ram_bytes(leaf, fi); |
| if (extent_type == BTRFS_FILE_EXTENT_REG || |
| extent_type == BTRFS_FILE_EXTENT_PREALLOC) { |
| disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); |
| extent_offset = btrfs_file_extent_offset(leaf, fi); |
| extent_end = found_key.offset + |
| btrfs_file_extent_num_bytes(leaf, fi); |
| disk_num_bytes = |
| btrfs_file_extent_disk_num_bytes(leaf, fi); |
| /* |
| * If the extent we got ends before our current offset, |
| * skip to the next extent. |
| */ |
| if (extent_end <= cur_offset) { |
| path->slots[0]++; |
| goto next_slot; |
| } |
| /* Skip holes */ |
| if (disk_bytenr == 0) |
| goto out_check; |
| /* Skip compressed/encrypted/encoded extents */ |
| if (btrfs_file_extent_compression(leaf, fi) || |
| btrfs_file_extent_encryption(leaf, fi) || |
| btrfs_file_extent_other_encoding(leaf, fi)) |
| goto out_check; |
| /* |
| * If extent is created before the last volume's snapshot |
| * this implies the extent is shared, hence we can't do |
| * nocow. This is the same check as in |
| * btrfs_cross_ref_exist but without calling |
| * btrfs_search_slot. |
| */ |
| if (!freespace_inode && |
| btrfs_file_extent_generation(leaf, fi) <= |
| btrfs_root_last_snapshot(&root->root_item)) |
| goto out_check; |
| if (extent_type == BTRFS_FILE_EXTENT_REG && !force) |
| goto out_check; |
| |
| /* |
| * The following checks can be expensive, as they need to |
| * take other locks and do btree or rbtree searches, so |
| * release the path to avoid blocking other tasks for too |
| * long. |
| */ |
| btrfs_release_path(path); |
| |
| ret = btrfs_cross_ref_exist(root, ino, |
| found_key.offset - |
| extent_offset, disk_bytenr, false); |
| if (ret) { |
| /* |
| * ret could be -EIO if the above fails to read |
| * metadata. |
| */ |
| if (ret < 0) { |
| if (cow_start != (u64)-1) |
| cur_offset = cow_start; |
| goto error; |
| } |
| |
| WARN_ON_ONCE(freespace_inode); |
| goto out_check; |
| } |
| disk_bytenr += extent_offset; |
| disk_bytenr += cur_offset - found_key.offset; |
| num_bytes = min(end + 1, extent_end) - cur_offset; |
| /* |
| * If there are pending snapshots for this root, we |
| * fall into common COW way |
| */ |
| if (!freespace_inode && atomic_read(&root->snapshot_force_cow)) |
| goto out_check; |
| /* |
| * force cow if csum exists in the range. |
| * this ensure that csum for a given extent are |
| * either valid or do not exist. |
| */ |
| ret = csum_exist_in_range(fs_info, disk_bytenr, |
| num_bytes); |
| if (ret) { |
| /* |
| * ret could be -EIO if the above fails to read |
| * metadata. |
| */ |
| if (ret < 0) { |
| if (cow_start != (u64)-1) |
| cur_offset = cow_start; |
| goto error; |
| } |
| WARN_ON_ONCE(freespace_inode); |
| goto out_check; |
| } |
| /* If the extent's block group is RO, we must COW */ |
| if (!btrfs_inc_nocow_writers(fs_info, disk_bytenr)) |
| goto out_check; |
| nocow = true; |
| } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { |
| extent_end = found_key.offset + ram_bytes; |
| extent_end = ALIGN(extent_end, fs_info->sectorsize); |
| /* Skip extents outside of our requested range */ |
| if (extent_end <= start) { |
| path->slots[0]++; |
| goto next_slot; |
| } |
| } else { |
| /* If this triggers then we have a memory corruption */ |
| BUG(); |
| } |
| out_check: |
| /* |
| * If nocow is false then record the beginning of the range |
| * that needs to be COWed |
| */ |
| if (!nocow) { |
| if (cow_start == (u64)-1) |
| cow_start = cur_offset; |
| cur_offset = extent_end; |
| if (cur_offset > end) |
| break; |
| if (!path->nodes[0]) |
| continue; |
| path->slots[0]++; |
| goto next_slot; |
| } |
| |
| /* |
| * COW range from cow_start to found_key.offset - 1. As the key |
| * will contain the beginning of the first extent that can be |
| * NOCOW, following one which needs to be COW'ed |
| */ |
| if (cow_start != (u64)-1) { |
| ret = fallback_to_cow(inode, locked_page, |
| cow_start, found_key.offset - 1, |
| page_started, nr_written); |
| if (ret) |
| goto error; |
| cow_start = (u64)-1; |
| } |
| |
| if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) { |
| u64 orig_start = found_key.offset - extent_offset; |
| struct extent_map *em; |
| |
| em = create_io_em(inode, cur_offset, num_bytes, |
| orig_start, |
| disk_bytenr, /* block_start */ |
| num_bytes, /* block_len */ |
| disk_num_bytes, /* orig_block_len */ |
| ram_bytes, BTRFS_COMPRESS_NONE, |
| BTRFS_ORDERED_PREALLOC); |
| if (IS_ERR(em)) { |
| ret = PTR_ERR(em); |
| goto error; |
| } |
| free_extent_map(em); |
| ret = btrfs_add_ordered_extent(inode, cur_offset, |
| disk_bytenr, num_bytes, |
| num_bytes, |
| BTRFS_ORDERED_PREALLOC); |
| if (ret) { |
| btrfs_drop_extent_cache(inode, cur_offset, |
| cur_offset + num_bytes - 1, |
| 0); |
| goto error; |
| } |
| } else { |
| ret = btrfs_add_ordered_extent(inode, cur_offset, |
| disk_bytenr, num_bytes, |
| num_bytes, |
| BTRFS_ORDERED_NOCOW); |
| if (ret) |
| goto error; |
| } |
| |
| if (nocow) |
| btrfs_dec_nocow_writers(fs_info, disk_bytenr); |
| nocow = false; |
| |
| if (btrfs_is_data_reloc_root(root)) |
| /* |
| * Error handled later, as we must prevent |
| * extent_clear_unlock_delalloc() in error handler |
| * from freeing metadata of created ordered extent. |
| */ |
| ret = btrfs_reloc_clone_csums(inode, cur_offset, |
| num_bytes); |
| |
| extent_clear_unlock_delalloc(inode, cur_offset, |
| cur_offset + num_bytes - 1, |
| locked_page, EXTENT_LOCKED | |
| EXTENT_DELALLOC | |
| EXTENT_CLEAR_DATA_RESV, |
| PAGE_UNLOCK | PAGE_SET_ORDERED); |
| |
| cur_offset = extent_end; |
| |
| /* |
| * btrfs_reloc_clone_csums() error, now we're OK to call error |
| * handler, as metadata for created ordered extent will only |
| * be freed by btrfs_finish_ordered_io(). |
| */ |
| if (ret) |
| goto error; |
| if (cur_offset > end) |
| break; |
| } |
| btrfs_release_path(path); |
| |
| if (cur_offset <= end && cow_start == (u64)-1) |
| cow_start = cur_offset; |
| |
| if (cow_start != (u64)-1) { |
| cur_offset = end; |
| ret = fallback_to_cow(inode, locked_page, cow_start, end, |
| page_started, nr_written); |
| if (ret) |
| goto error; |
| } |
| |
| error: |
| if (nocow) |
| btrfs_dec_nocow_writers(fs_info, disk_bytenr); |
| |
| if (ret && cur_offset < end) |
| extent_clear_unlock_delalloc(inode, cur_offset, end, |
| locked_page, EXTENT_LOCKED | |
| EXTENT_DELALLOC | EXTENT_DEFRAG | |
| EXTENT_DO_ACCOUNTING, PAGE_UNLOCK | |
| PAGE_START_WRITEBACK | |
| PAGE_END_WRITEBACK); |
| btrfs_free_path(path); |
| return ret; |
| } |
| |
| static bool should_nocow(struct btrfs_inode *inode, u64 start, u64 end) |
| { |
| if (inode->flags & (BTRFS_INODE_NODATACOW | BTRFS_INODE_PREALLOC)) { |
| if (inode->defrag_bytes && |
| test_range_bit(&inode->io_tree, start, end, EXTENT_DEFRAG, |
| 0, NULL)) |
| return false; |
| return true; |
| } |
| return false; |
| } |
| |
| /* |
| * Function to process delayed allocation (create CoW) for ranges which are |
| * being touched for the first time. |
| */ |
| int btrfs_run_delalloc_range(struct btrfs_inode *inode, struct page *locked_page, |
| u64 start, u64 end, int *page_started, unsigned long *nr_written, |
| struct writeback_control *wbc) |
| { |
| int ret; |
| const bool zoned = btrfs_is_zoned(inode->root->fs_info); |
| |
| /* |
| * The range must cover part of the @locked_page, or the returned |
| * @page_started can confuse the caller. |
| */ |
| ASSERT(!(end <= page_offset(locked_page) || |
| start >= page_offset(locked_page) + PAGE_SIZE)); |
| |
| if (should_nocow(inode, start, end)) { |
| /* |
| * Normally on a zoned device we're only doing COW writes, but |
| * in case of relocation on a zoned filesystem we have taken |
| * precaution, that we're only writing sequentially. It's safe |
| * to use run_delalloc_nocow() here, like for regular |
| * preallocated inodes. |
| */ |
| ASSERT(!zoned || |
| (zoned && btrfs_is_data_reloc_root(inode->root))); |
| ret = run_delalloc_nocow(inode, locked_page, start, end, |
| page_started, nr_written); |
| } else if (!inode_can_compress(inode) || |
| !inode_need_compress(inode, start, end)) { |
| if (zoned) |
| ret = run_delalloc_zoned(inode, locked_page, start, end, |
| page_started, nr_written); |
| else |
| ret = cow_file_range(inode, locked_page, start, end, |
| page_started, nr_written, 1); |
| } else { |
| set_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, &inode->runtime_flags); |
| ret = cow_file_range_async(inode, wbc, locked_page, start, end, |
| page_started, nr_written); |
| } |
| ASSERT(ret <= 0); |
| if (ret) |
| btrfs_cleanup_ordered_extents(inode, locked_page, start, |
| end - start + 1); |
| return ret; |
| } |
| |
| void btrfs_split_delalloc_extent(struct inode *inode, |
| struct extent_state *orig, u64 split) |
| { |
| u64 size; |
| |
| /* not delalloc, ignore it */ |
| if (!(orig->state & EXTENT_DELALLOC)) |
| return; |
| |
| size = orig->end - orig->start + 1; |
| if (size > BTRFS_MAX_EXTENT_SIZE) { |
| u32 num_extents; |
| u64 new_size; |
| |
| /* |
| * See the explanation in btrfs_merge_delalloc_extent, the same |
| * applies here, just in reverse. |
| */ |
| new_size = orig->end - split + 1; |
| num_extents = count_max_extents(new_size); |
| new_size = split - orig->start; |
| num_extents += count_max_extents(new_size); |
| if (count_max_extents(size) >= num_extents) |
| return; |
| } |
| |
| spin_lock(&BTRFS_I(inode)->lock); |
| btrfs_mod_outstanding_extents(BTRFS_I(inode), 1); |
| spin_unlock(&BTRFS_I(inode)->lock); |
| } |
| |
| /* |
| * Handle merged delayed allocation extents so we can keep track of new extents |
| * that are just merged onto old extents, such as when we are doing sequential |
| * writes, so we can properly account for the metadata space we'll need. |
| */ |
| void btrfs_merge_delalloc_extent(struct inode *inode, struct extent_state *new, |
| struct extent_state *other) |
| { |
| u64 new_size, old_size; |
| u32 num_extents; |
| |
| /* not delalloc, ignore it */ |
| if (!(other->state & EXTENT_DELALLOC)) |
| return; |
| |
| if (new->start > other->start) |
| new_size = new->end - other->start + 1; |
| else |
| new_size = other->end - new->start + 1; |
| |
| /* we're not bigger than the max, unreserve the space and go */ |
| if (new_size <= BTRFS_MAX_EXTENT_SIZE) { |
| spin_lock(&BTRFS_I(inode)->lock); |
| btrfs_mod_outstanding_extents(BTRFS_I(inode), -1); |
| spin_unlock(&BTRFS_I(inode)->lock); |
| return; |
| } |
| |
| /* |
| * We have to add up either side to figure out how many extents were |
| * accounted for before we merged into one big extent. If the number of |
| * extents we accounted for is <= the amount we need for the new range |
| * then we can return, otherwise drop. Think of it like this |
| * |
| * [ 4k][MAX_SIZE] |
| * |
| * So we've grown the extent by a MAX_SIZE extent, this would mean we |
| * need 2 outstanding extents, on one side we have 1 and the other side |
| * we have 1 so they are == and we can return. But in this case |
| * |
| * [MAX_SIZE+4k][MAX_SIZE+4k] |
| * |
| * Each range on their own accounts for 2 extents, but merged together |
| * they are only 3 extents worth of accounting, so we need to drop in |
| * this case. |
| */ |
| old_size = other->end - other->start + 1; |
| num_extents = count_max_extents(old_size); |
| old_size = new->end - new->start + 1; |
| num_extents += count_max_extents(old_size); |
| if (count_max_extents(new_size) >= num_extents) |
| return; |
| |
| spin_lock(&BTRFS_I(inode)->lock); |
| btrfs_mod_outstanding_extents(BTRFS_I(inode), -1); |
| spin_unlock(&BTRFS_I(inode)->lock); |
| } |
| |
| static void btrfs_add_delalloc_inodes(struct btrfs_root *root, |
| struct inode *inode) |
| { |
| struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); |
| |
| spin_lock(&root->delalloc_lock); |
| if (list_empty(&BTRFS_I(inode)->delalloc_inodes)) { |
| list_add_tail(&BTRFS_I(inode)->delalloc_inodes, |
| &root->delalloc_inodes); |
| set_bit(BTRFS_INODE_IN_DELALLOC_LIST, |
| &BTRFS_I(inode)->runtime_flags); |
| root->nr_delalloc_inodes++; |
| if (root->nr_delalloc_inodes == 1) { |
| spin_lock(&fs_info->delalloc_root_lock); |
| BUG_ON(!list_empty(&root->delalloc_root)); |
| list_add_tail(&root->delalloc_root, |
| &fs_info->delalloc_roots); |
| spin_unlock(&fs_info->delalloc_root_lock); |
| } |
| } |
| spin_unlock(&root->delalloc_lock); |
| } |
| |
| |
| void __btrfs_del_delalloc_inode(struct btrfs_root *root, |
| struct btrfs_inode *inode) |
| { |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| |
| if (!list_empty(&inode->delalloc_inodes)) { |
| list_del_init(&inode->delalloc_inodes); |
| clear_bit(BTRFS_INODE_IN_DELALLOC_LIST, |
| &inode->runtime_flags); |
| root->nr_delalloc_inodes--; |
| if (!root->nr_delalloc_inodes) { |
| ASSERT(list_empty(&root->delalloc_inodes)); |
| spin_lock(&fs_info->delalloc_root_lock); |
| BUG_ON(list_empty(&root->delalloc_root)); |
| list_del_init(&root->delalloc_root); |
| spin_unlock(&fs_info->delalloc_root_lock); |
| } |
| } |
| } |
| |
| static void btrfs_del_delalloc_inode(struct btrfs_root *root, |
| struct btrfs_inode *inode) |
| { |
| spin_lock(&root->delalloc_lock); |
| __btrfs_del_delalloc_inode(root, inode); |
| spin_unlock(&root->delalloc_lock); |
| } |
| |
| /* |
| * Properly track delayed allocation bytes in the inode and to maintain the |
| * list of inodes that have pending delalloc work to be done. |
| */ |
| void btrfs_set_delalloc_extent(struct inode *inode, struct extent_state *state, |
| unsigned *bits) |
| { |
| struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); |
| |
| if ((*bits & EXTENT_DEFRAG) && !(*bits & EXTENT_DELALLOC)) |
| WARN_ON(1); |
| /* |
| * set_bit and clear bit hooks normally require _irqsave/restore |
| * but in this case, we are only testing for the DELALLOC |
| * bit, which is only set or cleared with irqs on |
| */ |
| if (!(state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) { |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| u64 len = state->end + 1 - state->start; |
| u32 num_extents = count_max_extents(len); |
| bool do_list = !btrfs_is_free_space_inode(BTRFS_I(inode)); |
| |
| spin_lock(&BTRFS_I(inode)->lock); |
| btrfs_mod_outstanding_extents(BTRFS_I(inode), num_extents); |
| spin_unlock(&BTRFS_I(inode)->lock); |
| |
| /* For sanity tests */ |
| if (btrfs_is_testing(fs_info)) |
| return; |
| |
| percpu_counter_add_batch(&fs_info->delalloc_bytes, len, |
| fs_info->delalloc_batch); |
| spin_lock(&BTRFS_I(inode)->lock); |
| BTRFS_I(inode)->delalloc_bytes += len; |
| if (*bits & EXTENT_DEFRAG) |
| BTRFS_I(inode)->defrag_bytes += len; |
| if (do_list && !test_bit(BTRFS_INODE_IN_DELALLOC_LIST, |
| &BTRFS_I(inode)->runtime_flags)) |
| btrfs_add_delalloc_inodes(root, inode); |
| spin_unlock(&BTRFS_I(inode)->lock); |
| } |
| |
| if (!(state->state & EXTENT_DELALLOC_NEW) && |
| (*bits & EXTENT_DELALLOC_NEW)) { |
| spin_lock(&BTRFS_I(inode)->lock); |
| BTRFS_I(inode)->new_delalloc_bytes += state->end + 1 - |
| state->start; |
| spin_unlock(&BTRFS_I(inode)->lock); |
| } |
| } |
| |
| /* |
| * Once a range is no longer delalloc this function ensures that proper |
| * accounting happens. |
| */ |
| void btrfs_clear_delalloc_extent(struct inode *vfs_inode, |
| struct extent_state *state, unsigned *bits) |
| { |
| struct btrfs_inode *inode = BTRFS_I(vfs_inode); |
| struct btrfs_fs_info *fs_info = btrfs_sb(vfs_inode->i_sb); |
| u64 len = state->end + 1 - state->start; |
| u32 num_extents = count_max_extents(len); |
| |
| if ((state->state & EXTENT_DEFRAG) && (*bits & EXTENT_DEFRAG)) { |
| spin_lock(&inode->lock); |
| inode->defrag_bytes -= len; |
| spin_unlock(&inode->lock); |
| } |
| |
| /* |
| * set_bit and clear bit hooks normally require _irqsave/restore |
| * but in this case, we are only testing for the DELALLOC |
| * bit, which is only set or cleared with irqs on |
| */ |
| if ((state->state & EXTENT_DELALLOC) && (*bits & EXTENT_DELALLOC)) { |
| struct btrfs_root *root = inode->root; |
| bool do_list = !btrfs_is_free_space_inode(inode); |
| |
| spin_lock(&inode->lock); |
| btrfs_mod_outstanding_extents(inode, -num_extents); |
| spin_unlock(&inode->lock); |
| |
| /* |
| * We don't reserve metadata space for space cache inodes so we |
| * don't need to call delalloc_release_metadata if there is an |
| * error. |
| */ |
| if (*bits & EXTENT_CLEAR_META_RESV && |
| root != fs_info->tree_root) |
| btrfs_delalloc_release_metadata(inode, len, false); |
| |
| /* For sanity tests. */ |
| if (btrfs_is_testing(fs_info)) |
| return; |
| |
| if (!btrfs_is_data_reloc_root(root) && |
| do_list && !(state->state & EXTENT_NORESERVE) && |
| (*bits & EXTENT_CLEAR_DATA_RESV)) |
| btrfs_free_reserved_data_space_noquota(fs_info, len); |
| |
| percpu_counter_add_batch(&fs_info->delalloc_bytes, -len, |
| fs_info->delalloc_batch); |
| spin_lock(&inode->lock); |
| inode->delalloc_bytes -= len; |
| if (do_list && inode->delalloc_bytes == 0 && |
| test_bit(BTRFS_INODE_IN_DELALLOC_LIST, |
| &inode->runtime_flags)) |
| btrfs_del_delalloc_inode(root, inode); |
| spin_unlock(&inode->lock); |
| } |
| |
| if ((state->state & EXTENT_DELALLOC_NEW) && |
| (*bits & EXTENT_DELALLOC_NEW)) { |
| spin_lock(&inode->lock); |
| ASSERT(inode->new_delalloc_bytes >= len); |
| inode->new_delalloc_bytes -= len; |
| if (*bits & EXTENT_ADD_INODE_BYTES) |
| inode_add_bytes(&inode->vfs_inode, len); |
| spin_unlock(&inode->lock); |
| } |
| } |
| |
| /* |
| * in order to insert checksums into the metadata in large chunks, |
| * we wait until bio submission time. All the pages in the bio are |
| * checksummed and sums are attached onto the ordered extent record. |
| * |
| * At IO completion time the cums attached on the ordered extent record |
| * are inserted into the btree |
| */ |
| static blk_status_t btrfs_submit_bio_start(struct inode *inode, struct bio *bio, |
| u64 dio_file_offset) |
| { |
| return btrfs_csum_one_bio(BTRFS_I(inode), bio, 0, 0); |
| } |
| |
| /* |
| * Split an extent_map at [start, start + len] |
| * |
| * This function is intended to be used only for extract_ordered_extent(). |
| */ |
| static int split_zoned_em(struct btrfs_inode *inode, u64 start, u64 len, |
| u64 pre, u64 post) |
| { |
| struct extent_map_tree *em_tree = &inode->extent_tree; |
| struct extent_map *em; |
| struct extent_map *split_pre = NULL; |
| struct extent_map *split_mid = NULL; |
| struct extent_map *split_post = NULL; |
| int ret = 0; |
| unsigned long flags; |
| |
| /* Sanity check */ |
| if (pre == 0 && post == 0) |
| return 0; |
| |
| split_pre = alloc_extent_map(); |
| if (pre) |
| split_mid = alloc_extent_map(); |
| if (post) |
| split_post = alloc_extent_map(); |
| if (!split_pre || (pre && !split_mid) || (post && !split_post)) { |
| ret = -ENOMEM; |
| goto out; |
| } |
| |
| ASSERT(pre + post < len); |
| |
| lock_extent(&inode->io_tree, start, start + len - 1); |
| write_lock(&em_tree->lock); |
| em = lookup_extent_mapping(em_tree, start, len); |
| if (!em) { |
| ret = -EIO; |
| goto out_unlock; |
| } |
| |
| ASSERT(em->len == len); |
| ASSERT(!test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)); |
| ASSERT(em->block_start < EXTENT_MAP_LAST_BYTE); |
| ASSERT(test_bit(EXTENT_FLAG_PINNED, &em->flags)); |
| ASSERT(!test_bit(EXTENT_FLAG_LOGGING, &em->flags)); |
| ASSERT(!list_empty(&em->list)); |
| |
| flags = em->flags; |
| clear_bit(EXTENT_FLAG_PINNED, &em->flags); |
| |
| /* First, replace the em with a new extent_map starting from * em->start */ |
| split_pre->start = em->start; |
| split_pre->len = (pre ? pre : em->len - post); |
| split_pre->orig_start = split_pre->start; |
| split_pre->block_start = em->block_start; |
| split_pre->block_len = split_pre->len; |
| split_pre->orig_block_len = split_pre->block_len; |
| split_pre->ram_bytes = split_pre->len; |
| split_pre->flags = flags; |
| split_pre->compress_type = em->compress_type; |
| split_pre->generation = em->generation; |
| |
| replace_extent_mapping(em_tree, em, split_pre, 1); |
| |
| /* |
| * Now we only have an extent_map at: |
| * [em->start, em->start + pre] if pre != 0 |
| * [em->start, em->start + em->len - post] if pre == 0 |
| */ |
| |
| if (pre) { |
| /* Insert the middle extent_map */ |
| split_mid->start = em->start + pre; |
| split_mid->len = em->len - pre - post; |
| split_mid->orig_start = split_mid->start; |
| split_mid->block_start = em->block_start + pre; |
| split_mid->block_len = split_mid->len; |
| split_mid->orig_block_len = split_mid->block_len; |
| split_mid->ram_bytes = split_mid->len; |
| split_mid->flags = flags; |
| split_mid->compress_type = em->compress_type; |
| split_mid->generation = em->generation; |
| add_extent_mapping(em_tree, split_mid, 1); |
| } |
| |
| if (post) { |
| split_post->start = em->start + em->len - post; |
| split_post->len = post; |
| split_post->orig_start = split_post->start; |
| split_post->block_start = em->block_start + em->len - post; |
| split_post->block_len = split_post->len; |
| split_post->orig_block_len = split_post->block_len; |
| split_post->ram_bytes = split_post->len; |
| split_post->flags = flags; |
| split_post->compress_type = em->compress_type; |
| split_post->generation = em->generation; |
| add_extent_mapping(em_tree, split_post, 1); |
| } |
| |
| /* Once for us */ |
| free_extent_map(em); |
| /* Once for the tree */ |
| free_extent_map(em); |
| |
| out_unlock: |
| write_unlock(&em_tree->lock); |
| unlock_extent(&inode->io_tree, start, start + len - 1); |
| out: |
| free_extent_map(split_pre); |
| free_extent_map(split_mid); |
| free_extent_map(split_post); |
| |
| return ret; |
| } |
| |
| static blk_status_t extract_ordered_extent(struct btrfs_inode *inode, |
| struct bio *bio, loff_t file_offset) |
| { |
| struct btrfs_ordered_extent *ordered; |
| u64 start = (u64)bio->bi_iter.bi_sector << SECTOR_SHIFT; |
| u64 file_len; |
| u64 len = bio->bi_iter.bi_size; |
| u64 end = start + len; |
| u64 ordered_end; |
| u64 pre, post; |
| int ret = 0; |
| |
| ordered = btrfs_lookup_ordered_extent(inode, file_offset); |
| if (WARN_ON_ONCE(!ordered)) |
| return BLK_STS_IOERR; |
| |
| /* No need to split */ |
| if (ordered->disk_num_bytes == len) |
| goto out; |
| |
| /* We cannot split once end_bio'd ordered extent */ |
| if (WARN_ON_ONCE(ordered->bytes_left != ordered->disk_num_bytes)) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| /* We cannot split a compressed ordered extent */ |
| if (WARN_ON_ONCE(ordered->disk_num_bytes != ordered->num_bytes)) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| ordered_end = ordered->disk_bytenr + ordered->disk_num_bytes; |
| /* bio must be in one ordered extent */ |
| if (WARN_ON_ONCE(start < ordered->disk_bytenr || end > ordered_end)) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| /* Checksum list should be empty */ |
| if (WARN_ON_ONCE(!list_empty(&ordered->list))) { |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| file_len = ordered->num_bytes; |
| pre = start - ordered->disk_bytenr; |
| post = ordered_end - end; |
| |
| ret = btrfs_split_ordered_extent(ordered, pre, post); |
| if (ret) |
| goto out; |
| ret = split_zoned_em(inode, file_offset, file_len, pre, post); |
| |
| out: |
| btrfs_put_ordered_extent(ordered); |
| |
| return errno_to_blk_status(ret); |
| } |
| |
| /* |
| * extent_io.c submission hook. This does the right thing for csum calculation |
| * on write, or reading the csums from the tree before a read. |
| * |
| * Rules about async/sync submit, |
| * a) read: sync submit |
| * |
| * b) write without checksum: sync submit |
| * |
| * c) write with checksum: |
| * c-1) if bio is issued by fsync: sync submit |
| * (sync_writers != 0) |
| * |
| * c-2) if root is reloc root: sync submit |
| * (only in case of buffered IO) |
| * |
| * c-3) otherwise: async submit |
| */ |
| blk_status_t btrfs_submit_data_bio(struct inode *inode, struct bio *bio, |
| int mirror_num, unsigned long bio_flags) |
| |
| { |
| struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); |
| struct btrfs_root *root = BTRFS_I(inode)->root; |
| enum btrfs_wq_endio_type metadata = BTRFS_WQ_ENDIO_DATA; |
| blk_status_t ret = 0; |
| int skip_sum; |
| int async = !atomic_read(&BTRFS_I(inode)->sync_writers); |
| |
| skip_sum = (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) || |
| !fs_info->csum_root; |
| |
| if (btrfs_is_free_space_inode(BTRFS_I(inode))) |
| metadata = BTRFS_WQ_ENDIO_FREE_SPACE; |
| |
| if (bio_op(bio) == REQ_OP_ZONE_APPEND) { |
| struct page *page = bio_first_bvec_all(bio)->bv_page; |
| loff_t file_offset = page_offset(page); |
| |
| ret = extract_ordered_extent(BTRFS_I(inode), bio, file_offset); |
| if (ret) |
| goto out; |
| } |
| |
| if (btrfs_op(bio) != BTRFS_MAP_WRITE) { |
| ret = btrfs_bio_wq_end_io(fs_info, bio, metadata); |
| if (ret) |
| goto out; |
| |
| if (bio_flags & EXTENT_BIO_COMPRESSED) { |
| ret = btrfs_submit_compressed_read(inode, bio, |
| mirror_num, |
| bio_flags); |
| goto out; |
| } else { |
| /* |
| * Lookup bio sums does extra checks around whether we |
| * need to csum or not, which is why we ignore skip_sum |
| * here. |
| */ |
| ret = btrfs_lookup_bio_sums(inode, bio, NULL); |
| if (ret) |
| goto out; |
| } |
| goto mapit; |
| } else if (async && !skip_sum) { |
| /* csum items have already been cloned */ |
| if (btrfs_is_data_reloc_root(root)) |
| goto mapit; |
| /* we're doing a write, do the async checksumming */ |
| ret = btrfs_wq_submit_bio(inode, bio, mirror_num, bio_flags, |
| 0, btrfs_submit_bio_start); |
| goto out; |
| } else if (!skip_sum) { |
| ret = btrfs_csum_one_bio(BTRFS_I(inode), bio, 0, 0); |
| if (ret) |
| goto out; |
| } |
| |
| mapit: |
| ret = btrfs_map_bio(fs_info, bio, mirror_num); |
| |
| out: |
| if (ret) { |
| bio->bi_status = ret; |
| bio_endio(bio); |
| } |
| return ret; |
| } |
| |
| /* |
| * given a list of ordered sums record them in the inode. This happens |
| * at IO completion time based on sums calculated at bio submission time. |
| */ |
| static int add_pending_csums(struct btrfs_trans_handle *trans, |
| struct list_head *list) |
| { |
| struct btrfs_ordered_sum *sum; |
| int ret; |
| |
| list_for_each_entry(sum, list, list) { |
| trans->adding_csums = true; |
| ret = btrfs_csum_file_blocks(trans, trans->fs_info->csum_root, sum); |
| trans->adding_csums = false; |
| if (ret) |
| return ret; |
| } |
| return 0; |
| } |
| |
| static int btrfs_find_new_delalloc_bytes(struct btrfs_inode *inode, |
| const u64 start, |
| const u64 len, |
| struct extent_state **cached_state) |
| { |
| u64 search_start = start; |
| const u64 end = start + len - 1; |
| |
| while (search_start < end) { |
| const u64 search_len = end - search_start + 1; |
| struct extent_map *em; |
| u64 em_len; |
| int ret = 0; |
| |
| em = btrfs_get_extent(inode, NULL, 0, search_start, search_len); |
| if (IS_ERR(em)) |
| return PTR_ERR(em); |
| |
| if (em->block_start != EXTENT_MAP_HOLE) |
| goto next; |
| |
| em_len = em->len; |
| if (em->start < search_start) |
| em_len -= search_start - em->start; |
| if (em_len > search_len) |
| em_len = search_len; |
| |
| ret = set_extent_bit(&inode->io_tree, search_start, |
| search_start + em_len - 1, |
| EXTENT_DELALLOC_NEW, 0, NULL, cached_state, |
| GFP_NOFS, NULL); |
| next: |
| search_start = extent_map_end(em); |
| free_extent_map(em); |
| if (ret) |
| return ret; |
| } |
| return 0; |
| } |
| |
| int btrfs_set_extent_delalloc(struct btrfs_inode *inode, u64 start, u64 end, |
| unsigned int extra_bits, |
| struct extent_state **cached_state) |
| { |
| WARN_ON(PAGE_ALIGNED(end)); |
| |
| if (start >= i_size_read(&inode->vfs_inode) && |
| !(inode->flags & BTRFS_INODE_PREALLOC)) { |
| /* |
| * There can't be any extents following eof in this case so just |
| * set the delalloc new bit for the range directly. |
| */ |
| extra_bits |= EXTENT_DELALLOC_NEW; |
| } else { |
| int ret; |
| |
| ret = btrfs_find_new_delalloc_bytes(inode, start, |
| end + 1 - start, |
| cached_state); |
| if (ret) |
| return ret; |
| } |
| |
| return set_extent_delalloc(&inode->io_tree, start, end, extra_bits, |
| cached_state); |
| } |
| |
| /* see btrfs_writepage_start_hook for details on why this is required */ |
| struct btrfs_writepage_fixup { |
| struct page *page; |
| struct inode *inode; |
| struct btrfs_work work; |
| }; |
| |
| static void btrfs_writepage_fixup_worker(struct btrfs_work *work) |
| { |
| struct btrfs_writepage_fixup *fixup; |
| struct btrfs_ordered_extent *ordered; |
| struct extent_state *cached_state = NULL; |
| struct extent_changeset *data_reserved = NULL; |
| struct page *page; |
| struct btrfs_inode *inode; |
| u64 page_start; |
| u64 page_end; |
| int ret = 0; |
| bool free_delalloc_space = true; |
| |
| fixup = container_of(work, struct btrfs_writepage_fixup, work); |
| page = fixup->page; |
| inode = BTRFS_I(fixup->inode); |
| page_start = page_offset(page); |
| page_end = page_offset(page) + PAGE_SIZE - 1; |
| |
| /* |
| * This is similar to page_mkwrite, we need to reserve the space before |
| * we take the page lock. |
| */ |
| ret = btrfs_delalloc_reserve_space(inode, &data_reserved, page_start, |
| PAGE_SIZE); |
| again: |
| lock_page(page); |
| |
| /* |
| * Before we queued this fixup, we took a reference on the page. |
| * page->mapping may go NULL, but it shouldn't be moved to a different |
| * address space. |
| */ |
| if (!page->mapping || !PageDirty(page) || !PageChecked(page)) { |
| /* |
| * Unfortunately this is a little tricky, either |
| * |
| * 1) We got here and our page had already been dealt with and |
| * we reserved our space, thus ret == 0, so we need to just |
| * drop our space reservation and bail. This can happen the |
| * first time we come into the fixup worker, or could happen |
| * while waiting for the ordered extent. |
| * 2) Our page was already dealt with, but we happened to get an |
| * ENOSPC above from the btrfs_delalloc_reserve_space. In |
| * this case we obviously don't have anything to release, but |
| * because the page was already dealt with we don't want to |
| * mark the page with an error, so make sure we're resetting |
| * ret to 0. This is why we have this check _before_ the ret |
| * check, because we do not want to have a surprise ENOSPC |
| * when the page was already properly dealt with. |
| */ |
| if (!ret) { |
| btrfs_delalloc_release_extents(inode, PAGE_SIZE); |
| btrfs_delalloc_release_space(inode, data_reserved, |
| page_start, PAGE_SIZE, |
| true); |
| } |
| ret = 0; |
| goto out_page; |
| } |
| |
| /* |
| * We can't mess with the page state unless it is locked, so now that |
| * it is locked bail if we failed to make our space reservation. |
| */ |
| if (ret) |
| goto out_page; |
| |
| lock_extent_bits(&inode->io_tree, page_start, page_end, &cached_state); |
| |
| /* already ordered? We're done */ |
| if (PageOrdered(page)) |
| goto out_reserved; |
| |
| ordered = btrfs_lookup_ordered_range(inode, page_start, PAGE_SIZE); |
| if (ordered) { |
| unlock_extent_cached(&inode->io_tree, page_start, page_end, |
| &cached_state); |
| unlock_page(page); |
| btrfs_start_ordered_extent(ordered, 1); |
| btrfs_put_ordered_extent(ordered); |
| goto again; |
| } |
| |
| ret = btrfs_set_extent_delalloc(inode, page_start, page_end, 0, |
| &cached_state); |
| if (ret) |
| goto out_reserved; |
| |
| /* |
| * Everything went as planned, we're now the owner of a dirty page with |
| * delayed allocation bits set and space reserved for our COW |
| * destination. |
| * |
| * The page was dirty when we started, nothing should have cleaned it. |
| */ |
| BUG_ON(!PageDirty(page)); |
| free_delalloc_space = false; |
| out_reserved: |
| btrfs_delalloc_release_extents(inode, PAGE_SIZE); |
| if (free_delalloc_space) |
| btrfs_delalloc_release_space(inode, data_reserved, page_start, |
| PAGE_SIZE, true); |
| unlock_extent_cached(&inode->io_tree, page_start, page_end, |
| &cached_state); |
| out_page: |
| if (ret) { |
| /* |
| * We hit ENOSPC or other errors. Update the mapping and page |
| * to reflect the errors and clean the page. |
| */ |
| mapping_set_error(page->mapping, ret); |
| end_extent_writepage(page, ret, page_start, page_end); |
| clear_page_dirty_for_io(page); |
| SetPageError(page); |
| } |
| btrfs_page_clear_checked(inode->root->fs_info, page, page_start, PAGE_SIZE); |
| unlock_page(page); |
| put_page(page); |
| kfree(fixup); |
| extent_changeset_free(data_reserved); |
| /* |
| * As a precaution, do a delayed iput in case it would be the last iput |
| * that could need flushing space. Recursing back to fixup worker would |
| * deadlock. |
| */ |
| btrfs_add_delayed_iput(&inode->vfs_inode); |
| } |
| |
| /* |
| * There are a few paths in the higher layers of the kernel that directly |
| * set the page dirty bit without asking the filesystem if it is a |
| * good idea. This causes problems because we want to make sure COW |
| * properly happens and the data=ordered rules are followed. |
| * |
| * In our case any range that doesn't have the ORDERED bit set |
| * hasn't been properly setup for IO. We kick off an async process |
| * to fix it up. The async helper will wait for ordered extents, set |
| * the delalloc bit and make it safe to write the page. |
| */ |
| int btrfs_writepage_cow_fixup(struct page *page) |
| { |
| struct inode *inode = page->mapping->host; |
| struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); |
| struct btrfs_writepage_fixup *fixup; |
| |
| /* This page has ordered extent covering it already */ |
| if (PageOrdered(page)) |
| return 0; |
| |
| /* |
| * PageChecked is set below when we create a fixup worker for this page, |
| * don't try to create another one if we're already PageChecked() |
| * |
| * The extent_io writepage code will redirty the page if we send back |
| * EAGAIN. |
| */ |
| if (PageChecked(page)) |
| return -EAGAIN; |
| |
| fixup = kzalloc(sizeof(*fixup), GFP_NOFS); |
| if (!fixup) |
| return -EAGAIN; |
| |
| /* |
| * We are already holding a reference to this inode from |
| * write_cache_pages. We need to hold it because the space reservation |
| * takes place outside of the page lock, and we can't trust |
| * page->mapping outside of the page lock. |
| */ |
| ihold(inode); |
| btrfs_page_set_checked(fs_info, page, page_offset(page), PAGE_SIZE); |
| get_page(page); |
| btrfs_init_work(&fixup->work, btrfs_writepage_fixup_worker, NULL, NULL); |
| fixup->page = page; |
| fixup->inode = inode; |
| btrfs_queue_work(fs_info->fixup_workers, &fixup->work); |
| |
| return -EAGAIN; |
| } |
| |
| static int insert_reserved_file_extent(struct btrfs_trans_handle *trans, |
| struct btrfs_inode *inode, u64 file_pos, |
| struct btrfs_file_extent_item *stack_fi, |
| const bool update_inode_bytes, |
| u64 qgroup_reserved) |
| { |
| struct btrfs_root *root = inode->root; |
| const u64 sectorsize = root->fs_info->sectorsize; |
| struct btrfs_path *path; |
| struct extent_buffer *leaf; |
| struct btrfs_key ins; |
| u64 disk_num_bytes = btrfs_stack_file_extent_disk_num_bytes(stack_fi); |
| u64 disk_bytenr = btrfs_stack_file_extent_disk_bytenr(stack_fi); |
| u64 num_bytes = btrfs_stack_file_extent_num_bytes(stack_fi); |
| u64 ram_bytes = btrfs_stack_file_extent_ram_bytes(stack_fi); |
| struct btrfs_drop_extents_args drop_args = { 0 }; |
| int ret; |
| |
| path = btrfs_alloc_path(); |
| if (!path) |
| return -ENOMEM; |
| |
| /* |
| * we may be replacing one extent in the tree with another. |
| * The new extent is pinned in the extent map, and we don't want |
| * to drop it from the cache until it is completely in the btree. |
| * |
| * So, tell btrfs_drop_extents to leave this extent in the cache. |
| * the caller is expected to unpin it and allow it to be merged |
| * with the others. |
| */ |
| drop_args.path = path; |
| drop_args.start = file_pos; |
| drop_args.end = file_pos + num_bytes; |
| drop_args.replace_extent = true; |
| drop_args.extent_item_size = sizeof(*stack_fi); |
| ret = btrfs_drop_extents(trans, root, inode, &drop_args); |
| if (ret) |
| goto out; |
| |
| if (!drop_args.extent_inserted) { |
| ins.objectid = btrfs_ino(inode); |
| ins.offset = file_pos; |
| ins.type = BTRFS_EXTENT_DATA_KEY; |
| |
| ret = btrfs_insert_empty_item(trans, root, path, &ins, |
| sizeof(*stack_fi)); |
| if (ret) |
| goto out; |
| } |
| leaf = path->nodes[0]; |
| btrfs_set_stack_file_extent_generation(stack_fi, trans->transid); |
| write_extent_buffer(leaf, stack_fi, |
| btrfs_item_ptr_offset(leaf, path->slots[0]), |
| sizeof(struct btrfs_file_extent_item)); |
| |
| btrfs_mark_buffer_dirty(leaf); |
| btrfs_release_path(path); |
| |
| /* |
| * If we dropped an inline extent here, we know the range where it is |
| * was not marked with the EXTENT_DELALLOC_NEW bit, so we update the |
| * number of bytes only for that range containing the inline extent. |
| * The remaining of the range will be processed when clearning the |
| * EXTENT_DELALLOC_BIT bit through the ordered extent completion. |
| */ |
| if (file_pos == 0 && !IS_ALIGNED(drop_args.bytes_found, sectorsize)) { |
| u64 inline_size = round_down(drop_args.bytes_found, sectorsize); |
| |
| inline_size = drop_args.bytes_found - inline_size; |
| btrfs_update_inode_bytes(inode, sectorsize, inline_size); |
| drop_args.bytes_found -= inline_size; |
| num_bytes -= sectorsize; |
| } |
| |
| if (update_inode_bytes) |
| btrfs_update_inode_bytes(inode, num_bytes, drop_args.bytes_found); |
| |
| ins.objectid = disk_bytenr; |
| ins.offset = disk_num_bytes; |
| ins.type = BTRFS_EXTENT_ITEM_KEY; |
| |
| ret = btrfs_inode_set_file_extent_range(inode, file_pos, ram_bytes); |
| if (ret) |
| goto out; |
| |
| ret = btrfs_alloc_reserved_file_extent(trans, root, btrfs_ino(inode), |
| file_pos, qgroup_reserved, &ins); |
| out: |
| btrfs_free_path(path); |
| |
| return ret; |
| } |
| |
| static void btrfs_release_delalloc_bytes(struct btrfs_fs_info *fs_info, |
| u64 start, u64 len) |
| { |
| struct btrfs_block_group *cache; |
| |
| cache = btrfs_lookup_block_group(fs_info, start); |
| ASSERT(cache); |
| |
| spin_lock(&cache->lock); |
| cache->delalloc_bytes -= len; |
| spin_unlock(&cache->lock); |
| |
| btrfs_put_block_group(cache); |
| } |
| |
| static int insert_ordered_extent_file_extent(struct btrfs_trans_handle *trans, |
| struct btrfs_ordered_extent *oe) |
| { |
| struct btrfs_file_extent_item stack_fi; |
| u64 logical_len; |
| bool update_inode_bytes; |
| |
| memset(&stack_fi, 0, sizeof(stack_fi)); |
| btrfs_set_stack_file_extent_type(&stack_fi, BTRFS_FILE_EXTENT_REG); |
| btrfs_set_stack_file_extent_disk_bytenr(&stack_fi, oe->disk_bytenr); |
| btrfs_set_stack_file_extent_disk_num_bytes(&stack_fi, |
| oe->disk_num_bytes); |
| if (test_bit(BTRFS_ORDERED_TRUNCATED, &oe->flags)) |
| logical_len = oe->truncated_len; |
| else |
| logical_len = oe->num_bytes; |
| btrfs_set_stack_file_extent_num_bytes(&stack_fi, logical_len); |
| btrfs_set_stack_file_extent_ram_bytes(&stack_fi, logical_len); |
| btrfs_set_stack_file_extent_compression(&stack_fi, oe->compress_type); |
| /* Encryption and other encoding is reserved and all 0 */ |
| |
| /* |
| * For delalloc, when completing an ordered extent we update the inode's |
| * bytes when clearing the range in the inode's io tree, so pass false |
| * as the argument 'update_inode_bytes' to insert_reserved_file_extent(), |
| * except if the ordered extent was truncated. |
| */ |
| update_inode_bytes = test_bit(BTRFS_ORDERED_DIRECT, &oe->flags) || |
| test_bit(BTRFS_ORDERED_TRUNCATED, &oe->flags); |
| |
| return insert_reserved_file_extent(trans, BTRFS_I(oe->inode), |
| oe->file_offset, &stack_fi, |
| update_inode_bytes, oe->qgroup_rsv); |
| } |
| |
| /* |
| * As ordered data IO finishes, this gets called so we can finish |
| * an ordered extent if the range of bytes in the file it covers are |
| * fully written. |
| */ |
| static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent) |
| { |
| struct btrfs_inode *inode = BTRFS_I(ordered_extent->inode); |
| struct btrfs_root *root = inode->root; |
| struct btrfs_fs_info *fs_info = root->fs_info; |
| struct btrfs_trans_handle *trans = NULL; |
| struct extent_io_tree *io_tree = &inode->io_tree; |
| struct extent_state *cached_state = NULL; |
| u64 start, end; |
| int compress_type = 0; |
| int ret = 0; |
| u64 logical_len = ordered_extent->num_bytes; |
| bool freespace_inode; |
| bool truncated = false; |
| bool clear_reserved_extent = true; |
| unsigned int clear_bits = EXTENT_DEFRAG; |
| |
| start = ordered_extent->file_offset; |
| end = start + ordered_extent->num_bytes - 1; |
| |
| 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)) |
| clear_bits |= EXTENT_DELALLOC_NEW; |
| |
| freespace_inode = btrfs_is_free_space_inode(inode); |
| |
| if (test_bit(BTRFS_ORDERED_IOERR, &ordered_extent->flags)) { |
| ret = -EIO; |
| goto out; |
| } |
| |
| /* A valid bdev implies a write on a sequential zone */ |
| if (ordered_extent->bdev) { |
| btrfs_rewrite_logical_zoned(ordered_extent); |
| btrfs_zone_finish_endio(fs_info, ordered_extent->disk_bytenr, |
| ordered_extent->disk_num_bytes); |
| } |
| |
| btrfs_free_io_failure_record(inode, start, end); |
| |
| if (test_bit(BTRFS_ORDERED_TRUNCATED, &ordered_extent->flags)) { |
| truncated = true; |
| logical_len = ordered_extent->truncated_len; |
| /* Truncated the entire extent, don't bother adding */ |
| if (!logical_len) |
| goto out; |
| } |
| |
| if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) { |
| BUG_ON(!list_empty(&ordered_extent->list)); /* Logic error */ |
| |
| btrfs_inode_safe_disk_i_size_write(inode, 0); |
| if (freespace_inode) |
| trans = btrfs_join_transaction_spacecache(root); |
| else |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| trans = NULL; |
| goto out; |
| } |
| trans->block_rsv = &inode->block_rsv; |
| ret = btrfs_update_inode_fallback(trans, root, inode); |
| if (ret) /* -ENOMEM or corruption */ |
| btrfs_abort_transaction(trans, ret); |
| goto out; |
| } |
| |
| clear_bits |= EXTENT_LOCKED; |
| lock_extent_bits(io_tree, start, end, &cached_state); |
| |
| if (freespace_inode) |
| trans = btrfs_join_transaction_spacecache(root); |
| else |
| trans = btrfs_join_transaction(root); |
| if (IS_ERR(trans)) { |
| ret = PTR_ERR(trans); |
| trans = NULL; |
| goto out; |
| } |
| |
| trans->block_rsv = &inode->block_rsv; |
| |
| if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags)) |
| compress_type = ordered_extent->compress_type; |
| if (test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) { |
| BUG_ON(compress_type); |
| ret = btrfs_mark_extent_written(trans, inode, |
| ordered_extent->file_offset, |
| ordered_extent->file_offset + |
| logical_len); |
| } else { |
| BUG_ON(root == fs_info->tree_root); |
| ret = insert_ordered_extent_file_extent(trans, ordered_extent); |
| if (!ret) { |
| clear_reserved_extent = false; |
| btrfs_release_delalloc_bytes(fs_info, |
| ordered_extent->disk_bytenr, |
| ordered_extent->disk_num_bytes); |
| } |
| } |
| unpin_extent_cache(&inode->extent_tree, ordered_extent->file_offset, |
| ordered_extent->num_bytes, trans->transid); |
| if (ret < 0) { |
| btrfs_abort_transaction(trans, ret); |
| goto out; |
| } |
| |
| ret = add_pending_csums(trans, &ordered_extent->list); |
| if (ret) { |
| btrfs_abort_transaction(trans, ret); |
| goto out; |
| } |
| |
| /* |
| * If this is a new delalloc range, clear its new delalloc flag to |
| * update the inode's number of bytes. This needs to be done first |
| * before updating the inode item. |
| */ |
| if ((clear_bits & EXTENT_DELALLOC_NEW) && |
| !test_bit(BTRFS_ORDERED_TRUNCATED, &ordered_extent->flags)) |
| clear_extent_bit(&inode->io_tree, start, end, |
| EXTENT_DELALLOC_NEW | EXTENT_ADD_INODE_BYTES, |
| 0, 0, &cached_state); |
| |
| btrfs_inode_safe_disk_i_size_write(inode, 0); |
| ret = btrfs_update_inode_fallback(trans, root, inode); |
| if (ret) { /* -ENOMEM or corruption */ |
| btrfs_abort_transaction(trans, ret); |
| goto out; |
| } |
| ret = 0; |
| out: |
| clear_extent_bit(&inode->io_tree, start, end, clear_bits, |
| (clear_bits & EXTENT_LOCKED) ? 1 : 0, 0, |
| &cached_state); |
| |
| if (trans) |
| btrfs_end_transaction(trans); |
|