/* * Copyright (C) 2007 Oracle. All rights reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public * License v2 as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public * License along with this program; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 021110-1307, USA. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "compat.h" #include "ctree.h" #include "disk-io.h" #include "transaction.h" #include "btrfs_inode.h" #include "ioctl.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 "inode-map.h" struct btrfs_iget_args { u64 ino; struct btrfs_root *root; }; static const struct inode_operations btrfs_dir_inode_operations; static const struct inode_operations btrfs_symlink_inode_operations; static const struct inode_operations btrfs_dir_ro_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 address_space_operations btrfs_symlink_aops; static const struct file_operations btrfs_dir_file_operations; static struct extent_io_ops btrfs_extent_io_ops; static struct kmem_cache *btrfs_inode_cachep; struct kmem_cache *btrfs_trans_handle_cachep; struct kmem_cache *btrfs_transaction_cachep; struct kmem_cache *btrfs_path_cachep; struct kmem_cache *btrfs_free_space_cachep; #define S_SHIFT 12 static unsigned char btrfs_type_by_mode[S_IFMT >> S_SHIFT] = { [S_IFREG >> S_SHIFT] = BTRFS_FT_REG_FILE, [S_IFDIR >> S_SHIFT] = BTRFS_FT_DIR, [S_IFCHR >> S_SHIFT] = BTRFS_FT_CHRDEV, [S_IFBLK >> S_SHIFT] = BTRFS_FT_BLKDEV, [S_IFIFO >> S_SHIFT] = BTRFS_FT_FIFO, [S_IFSOCK >> S_SHIFT] = BTRFS_FT_SOCK, [S_IFLNK >> S_SHIFT] = BTRFS_FT_SYMLINK, }; static int btrfs_setsize(struct inode *inode, loff_t newsize); static int btrfs_truncate(struct inode *inode); static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end); static noinline int cow_file_range(struct inode *inode, struct page *locked_page, u64 start, u64 end, int *page_started, unsigned long *nr_written, int unlock); static noinline int btrfs_update_inode_fallback(struct btrfs_trans_handle *trans, struct btrfs_root *root, 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 noinline int insert_inline_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode, u64 start, size_t size, size_t compressed_size, int compress_type, struct page **compressed_pages) { struct btrfs_key key; struct btrfs_path *path; struct extent_buffer *leaf; struct page *page = NULL; char *kaddr; unsigned long ptr; struct btrfs_file_extent_item *ei; int err = 0; int ret; size_t cur_size = size; size_t datasize; unsigned long offset; if (compressed_size && compressed_pages) cur_size = compressed_size; path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->leave_spinning = 1; key.objectid = btrfs_ino(inode); key.offset = start; btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY); datasize = btrfs_file_extent_calc_inline_size(cur_size); inode_add_bytes(inode, size); ret = btrfs_insert_empty_item(trans, root, path, &key, datasize); BUG_ON(ret); if (ret) { err = 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_CACHE_SIZE); kaddr = kmap_atomic(cpage, KM_USER0); write_extent_buffer(leaf, kaddr, ptr, cur_size); kunmap_atomic(kaddr, KM_USER0); 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_CACHE_SHIFT); btrfs_set_file_extent_compression(leaf, ei, 0); kaddr = kmap_atomic(page, KM_USER0); offset = start & (PAGE_CACHE_SIZE - 1); write_extent_buffer(leaf, kaddr + offset, ptr, size); kunmap_atomic(kaddr, KM_USER0); page_cache_release(page); } btrfs_mark_buffer_dirty(leaf); btrfs_free_path(path); /* * 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; btrfs_update_inode(trans, root, inode); return 0; fail: btrfs_free_path(path); return err; } /* * 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_trans_handle *trans, struct btrfs_root *root, struct inode *inode, u64 start, u64 end, size_t compressed_size, int compress_type, struct page **compressed_pages) { u64 isize = i_size_read(inode); u64 actual_end = min(end + 1, isize); u64 inline_len = actual_end - start; u64 aligned_end = (end + root->sectorsize - 1) & ~((u64)root->sectorsize - 1); u64 hint_byte; u64 data_len = inline_len; int ret; if (compressed_size) data_len = compressed_size; if (start > 0 || actual_end >= PAGE_CACHE_SIZE || data_len >= BTRFS_MAX_INLINE_DATA_SIZE(root) || (!compressed_size && (actual_end & (root->sectorsize - 1)) == 0) || end + 1 < isize || data_len > root->fs_info->max_inline) { return 1; } ret = btrfs_drop_extents(trans, inode, start, aligned_end, &hint_byte, 1); BUG_ON(ret); if (isize > actual_end) inline_len = min_t(u64, isize, actual_end); ret = insert_inline_extent(trans, root, inode, start, inline_len, compressed_size, compress_type, compressed_pages); BUG_ON(ret); btrfs_delalloc_release_metadata(inode, end + 1 - start); btrfs_drop_extent_cache(inode, start, aligned_end - 1, 0); return 0; } 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_cow { struct inode *inode; struct btrfs_root *root; struct page *locked_page; u64 start; u64 end; struct list_head extents; struct btrfs_work work; }; static noinline int add_async_extent(struct async_cow *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); 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; } /* * 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 pdflush sent them down. */ static noinline int compress_file_range(struct inode *inode, struct page *locked_page, u64 start, u64 end, struct async_cow *async_cow, int *num_added) { struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; u64 num_bytes; u64 blocksize = root->sectorsize; u64 actual_end; u64 isize = i_size_read(inode); int ret = 0; struct page **pages = NULL; unsigned long nr_pages; unsigned long nr_pages_ret = 0; unsigned long total_compressed = 0; unsigned long total_in = 0; unsigned long max_compressed = 128 * 1024; unsigned long max_uncompressed = 128 * 1024; int i; int will_compress; int compress_type = root->fs_info->compress_type; /* if this is a small write inside eof, kick off a defragbot */ if (end <= BTRFS_I(inode)->disk_i_size && (end - start + 1) < 16 * 1024) btrfs_add_inode_defrag(NULL, inode); actual_end = min_t(u64, isize, end + 1); again: will_compress = 0; nr_pages = (end >> PAGE_CACHE_SHIFT) - (start >> PAGE_CACHE_SHIFT) + 1; nr_pages = min(nr_pages, (128 * 1024UL) / PAGE_CACHE_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; /* we want to make sure that amount of ram required to uncompress * an extent is reasonable, so we limit the total size in ram * of a compressed extent to 128k. This is a crucial number * because it also controls how easily we can spread reads across * cpus for decompression. * * We also want to make sure the amount of IO required to do * a random read is reasonably small, so we limit the size of * a compressed extent to 128k. */ total_compressed = min(total_compressed, max_uncompressed); num_bytes = (end - start + blocksize) & ~(blocksize - 1); num_bytes = max(blocksize, num_bytes); 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 (!(BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) && (btrfs_test_opt(root, COMPRESS) || (BTRFS_I(inode)->force_compress) || (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS))) { WARN_ON(pages); pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS); if (!pages) { /* just bail out to the uncompressed code */ goto cont; } if (BTRFS_I(inode)->force_compress) compress_type = BTRFS_I(inode)->force_compress; ret = btrfs_compress_pages(compress_type, inode->i_mapping, start, total_compressed, pages, nr_pages, &nr_pages_ret, &total_in, &total_compressed, max_compressed); if (!ret) { unsigned long offset = total_compressed & (PAGE_CACHE_SIZE - 1); struct page *page = pages[nr_pages_ret - 1]; char *kaddr; /* zero the tail end of the last page, we might be * sending it down to disk */ if (offset) { kaddr = kmap_atomic(page, KM_USER0); memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset); kunmap_atomic(kaddr, KM_USER0); } will_compress = 1; } } cont: if (start == 0) { trans = btrfs_join_transaction(root); BUG_ON(IS_ERR(trans)); trans->block_rsv = &root->fs_info->delalloc_block_rsv; /* lets try to make an inline extent */ if (ret || total_in < (actual_end - start)) { /* we didn't compress the entire range, try * to make an uncompressed inline extent. */ ret = cow_file_range_inline(trans, root, inode, start, end, 0, 0, NULL); } else { /* try making a compressed inline extent */ ret = cow_file_range_inline(trans, root, inode, start, end, total_compressed, compress_type, pages); } if (ret == 0) { /* * inline extent creation worked, we don't need * to create any more async work items. Unlock * and free up our temp pages. */ extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, start, end, NULL, EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_DIRTY | EXTENT_CLEAR_DELALLOC | EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK); btrfs_end_transaction(trans, root); goto free_pages_out; } btrfs_end_transaction(trans, root); } 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 = (total_compressed + blocksize - 1) & ~(blocksize - 1); /* * one last check to make sure the compression is really a * win, compare the page count read with the blocks on disk */ total_in = (total_in + PAGE_CACHE_SIZE - 1) & ~(PAGE_CACHE_SIZE - 1); if (total_compressed >= total_in) { will_compress = 0; } else { num_bytes = total_in; } } if (!will_compress && 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_ret; i++) { WARN_ON(pages[i]->mapping); page_cache_release(pages[i]); } kfree(pages); pages = NULL; total_compressed = 0; nr_pages_ret = 0; /* flag the file so we don't compress in the future */ if (!btrfs_test_opt(root, FORCE_COMPRESS) && !(BTRFS_I(inode)->force_compress)) { BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS; } } if (will_compress) { *num_added += 1; /* 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_cow, start, num_bytes, total_compressed, pages, nr_pages_ret, compress_type); if (start + num_bytes < end) { start += num_bytes; pages = NULL; cond_resched(); goto again; } } else { 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 (page_offset(locked_page) >= start && page_offset(locked_page) <= end) { __set_page_dirty_nobuffers(locked_page); /* unlocked later on in the async handlers */ } add_async_extent(async_cow, start, end - start + 1, 0, NULL, 0, BTRFS_COMPRESS_NONE); *num_added += 1; } out: return 0; free_pages_out: for (i = 0; i < nr_pages_ret; i++) { WARN_ON(pages[i]->mapping); page_cache_release(pages[i]); } kfree(pages); goto out; } /* * 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 int submit_compressed_extents(struct inode *inode, struct async_cow *async_cow) { struct async_extent *async_extent; u64 alloc_hint = 0; struct btrfs_trans_handle *trans; struct btrfs_key ins; struct extent_map *em; struct btrfs_root *root = BTRFS_I(inode)->root; struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; struct extent_io_tree *io_tree; int ret = 0; if (list_empty(&async_cow->extents)) return 0; while (!list_empty(&async_cow->extents)) { async_extent = list_entry(async_cow->extents.next, struct async_extent, list); list_del(&async_extent->list); io_tree = &BTRFS_I(inode)->io_tree; retry: /* did the compression code fall back to uncompressed IO? */ if (!async_extent->pages) { int page_started = 0; unsigned long nr_written = 0; lock_extent(io_tree, async_extent->start, async_extent->start + async_extent->ram_size - 1, GFP_NOFS); /* allocate blocks */ ret = cow_file_range(inode, async_cow->locked_page, async_extent->start, async_extent->start + async_extent->ram_size - 1, &page_started, &nr_written, 0); /* * if page_started, cow_file_range inserted an * inline extent and took care of all the unlocking * and IO for us. Otherwise, we need to submit * all those pages down to the drive. */ if (!page_started && !ret) extent_write_locked_range(io_tree, inode, async_extent->start, async_extent->start + async_extent->ram_size - 1, btrfs_get_extent, WB_SYNC_ALL); kfree(async_extent); cond_resched(); continue; } lock_extent(io_tree, async_extent->start, async_extent->start + async_extent->ram_size - 1, GFP_NOFS); trans = btrfs_join_transaction(root); BUG_ON(IS_ERR(trans)); trans->block_rsv = &root->fs_info->delalloc_block_rsv; ret = btrfs_reserve_extent(trans, root, async_extent->compressed_size, async_extent->compressed_size, 0, alloc_hint, (u64)-1, &ins, 1); btrfs_end_transaction(trans, root); if (ret) { int i; for (i = 0; i < async_extent->nr_pages; i++) { WARN_ON(async_extent->pages[i]->mapping); page_cache_release(async_extent->pages[i]); } kfree(async_extent->pages); async_extent->nr_pages = 0; async_extent->pages = NULL; unlock_extent(io_tree, async_extent->start, async_extent->start + async_extent->ram_size - 1, GFP_NOFS); goto retry; } /* * here we're doing allocation and writeback of the * compressed pages */ btrfs_drop_extent_cache(inode, async_extent->start, async_extent->start + async_extent->ram_size - 1, 0); em = alloc_extent_map(); BUG_ON(!em); em->start = async_extent->start; em->len = async_extent->ram_size; em->orig_start = em->start; em->block_start = ins.objectid; em->block_len = ins.offset; em->bdev = root->fs_info->fs_devices->latest_bdev; em->compress_type = async_extent->compress_type; set_bit(EXTENT_FLAG_PINNED, &em->flags); set_bit(EXTENT_FLAG_COMPRESSED, &em->flags); while (1) { write_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em); write_unlock(&em_tree->lock); if (ret != -EEXIST) { free_extent_map(em); break; } btrfs_drop_extent_cache(inode, async_extent->start, async_extent->start + async_extent->ram_size - 1, 0); } ret = btrfs_add_ordered_extent_compress(inode, async_extent->start, ins.objectid, async_extent->ram_size, ins.offset, BTRFS_ORDERED_COMPRESSED, async_extent->compress_type); BUG_ON(ret); /* * clear dirty, set writeback and unlock the pages. */ extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, async_extent->start, async_extent->start + async_extent->ram_size - 1, NULL, EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC | EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK); ret = btrfs_submit_compressed_write(inode, async_extent->start, async_extent->ram_size, ins.objectid, ins.offset, async_extent->pages, async_extent->nr_pages); BUG_ON(ret); alloc_hint = ins.objectid + ins.offset; kfree(async_extent); cond_resched(); } return 0; } static u64 get_extent_allocation_hint(struct inode *inode, u64 start, u64 num_bytes) { struct extent_map_tree *em_tree = &BTRFS_I(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 inode *inode, struct page *locked_page, u64 start, u64 end, int *page_started, unsigned long *nr_written, int unlock) { struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; u64 alloc_hint = 0; u64 num_bytes; unsigned long ram_size; u64 disk_num_bytes; u64 cur_alloc_size; u64 blocksize = root->sectorsize; struct btrfs_key ins; struct extent_map *em; struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; int ret = 0; BUG_ON(btrfs_is_free_space_inode(root, inode)); trans = btrfs_join_transaction(root); BUG_ON(IS_ERR(trans)); trans->block_rsv = &root->fs_info->delalloc_block_rsv; num_bytes = (end - start + blocksize) & ~(blocksize - 1); num_bytes = max(blocksize, num_bytes); disk_num_bytes = num_bytes; ret = 0; /* if this is a small write inside eof, kick off defrag */ if (end <= BTRFS_I(inode)->disk_i_size && num_bytes < 64 * 1024) btrfs_add_inode_defrag(trans, inode); if (start == 0) { /* lets try to make an inline extent */ ret = cow_file_range_inline(trans, root, inode, start, end, 0, 0, NULL); if (ret == 0) { extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, start, end, NULL, EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC | EXTENT_CLEAR_DIRTY | EXTENT_SET_WRITEBACK | EXTENT_END_WRITEBACK); *nr_written = *nr_written + (end - start + PAGE_CACHE_SIZE) / PAGE_CACHE_SIZE; *page_started = 1; ret = 0; goto out; } } BUG_ON(disk_num_bytes > btrfs_super_total_bytes(root->fs_info->super_copy)); alloc_hint = get_extent_allocation_hint(inode, start, num_bytes); btrfs_drop_extent_cache(inode, start, start + num_bytes - 1, 0); while (disk_num_bytes > 0) { unsigned long op; cur_alloc_size = disk_num_bytes; ret = btrfs_reserve_extent(trans, root, cur_alloc_size, root->sectorsize, 0, alloc_hint, (u64)-1, &ins, 1); BUG_ON(ret); em = alloc_extent_map(); BUG_ON(!em); em->start = start; em->orig_start = em->start; ram_size = ins.offset; em->len = ins.offset; em->block_start = ins.objectid; em->block_len = ins.offset; em->bdev = root->fs_info->fs_devices->latest_bdev; set_bit(EXTENT_FLAG_PINNED, &em->flags); while (1) { write_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em); write_unlock(&em_tree->lock); if (ret != -EEXIST) { free_extent_map(em); break; } btrfs_drop_extent_cache(inode, start, start + ram_size - 1, 0); } cur_alloc_size = ins.offset; ret = btrfs_add_ordered_extent(inode, start, ins.objectid, ram_size, cur_alloc_size, 0); BUG_ON(ret); if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID) { ret = btrfs_reloc_clone_csums(inode, start, cur_alloc_size); BUG_ON(ret); } if (disk_num_bytes < cur_alloc_size) break; /* 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 Private2 bit so we know this page was properly * setup for writepage */ op = unlock ? EXTENT_CLEAR_UNLOCK_PAGE : 0; op |= EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC | EXTENT_SET_PRIVATE2; extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, start, start + ram_size - 1, locked_page, op); disk_num_bytes -= cur_alloc_size; num_bytes -= cur_alloc_size; alloc_hint = ins.objectid + ins.offset; start += cur_alloc_size; } out: ret = 0; btrfs_end_transaction(trans, root); return ret; } /* * work queue call back to started compression on a file and pages */ static noinline void async_cow_start(struct btrfs_work *work) { struct async_cow *async_cow; int num_added = 0; async_cow = container_of(work, struct async_cow, work); compress_file_range(async_cow->inode, async_cow->locked_page, async_cow->start, async_cow->end, async_cow, &num_added); if (num_added == 0) async_cow->inode = NULL; } /* * work queue call back to submit previously compressed pages */ static noinline void async_cow_submit(struct btrfs_work *work) { struct async_cow *async_cow; struct btrfs_root *root; unsigned long nr_pages; async_cow = container_of(work, struct async_cow, work); root = async_cow->root; nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >> PAGE_CACHE_SHIFT; atomic_sub(nr_pages, &root->fs_info->async_delalloc_pages); if (atomic_read(&root->fs_info->async_delalloc_pages) < 5 * 1042 * 1024 && waitqueue_active(&root->fs_info->async_submit_wait)) wake_up(&root->fs_info->async_submit_wait); if (async_cow->inode) submit_compressed_extents(async_cow->inode, async_cow); } static noinline void async_cow_free(struct btrfs_work *work) { struct async_cow *async_cow; async_cow = container_of(work, struct async_cow, work); kfree(async_cow); } static int cow_file_range_async(struct inode *inode, struct page *locked_page, u64 start, u64 end, int *page_started, unsigned long *nr_written) { struct async_cow *async_cow; struct btrfs_root *root = BTRFS_I(inode)->root; unsigned long nr_pages; u64 cur_end; int limit = 10 * 1024 * 1042; clear_extent_bit(&BTRFS_I(inode)->io_tree, start, end, EXTENT_LOCKED, 1, 0, NULL, GFP_NOFS); while (start < end) { async_cow = kmalloc(sizeof(*async_cow), GFP_NOFS); BUG_ON(!async_cow); async_cow->inode = inode; async_cow->root = root; async_cow->locked_page = locked_page; async_cow->start = start; if (BTRFS_I(inode)->flags & BTRFS_INODE_NOCOMPRESS) cur_end = end; else cur_end = min(end, start + 512 * 1024 - 1); async_cow->end = cur_end; INIT_LIST_HEAD(&async_cow->extents); async_cow->work.func = async_cow_start; async_cow->work.ordered_func = async_cow_submit; async_cow->work.ordered_free = async_cow_free; async_cow->work.flags = 0; nr_pages = (cur_end - start + PAGE_CACHE_SIZE) >> PAGE_CACHE_SHIFT; atomic_add(nr_pages, &root->fs_info->async_delalloc_pages); btrfs_queue_worker(&root->fs_info->delalloc_workers, &async_cow->work); if (atomic_read(&root->fs_info->async_delalloc_pages) > limit) { wait_event(root->fs_info->async_submit_wait, (atomic_read(&root->fs_info->async_delalloc_pages) < limit)); } while (atomic_read(&root->fs_info->async_submit_draining) && atomic_read(&root->fs_info->async_delalloc_pages)) { wait_event(root->fs_info->async_submit_wait, (atomic_read(&root->fs_info->async_delalloc_pages) == 0)); } *nr_written += nr_pages; start = cur_end + 1; } *page_started = 1; return 0; } static noinline int csum_exist_in_range(struct btrfs_root *root, u64 bytenr, u64 num_bytes) { int ret; struct btrfs_ordered_sum *sums; LIST_HEAD(list); ret = btrfs_lookup_csums_range(root->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); } return 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 inode *inode, struct page *locked_page, u64 start, u64 end, int *page_started, int force, unsigned long *nr_written) { struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; struct extent_buffer *leaf; struct btrfs_path *path; struct btrfs_file_extent_item *fi; struct btrfs_key found_key; u64 cow_start; u64 cur_offset; u64 extent_end; u64 extent_offset; u64 disk_bytenr; u64 num_bytes; int extent_type; int ret; int type; int nocow; int check_prev = 1; bool nolock; u64 ino = btrfs_ino(inode); path = btrfs_alloc_path(); if (!path) return -ENOMEM; nolock = btrfs_is_free_space_inode(root, inode); if (nolock) trans = btrfs_join_transaction_nolock(root); else trans = btrfs_join_transaction(root); BUG_ON(IS_ERR(trans)); trans->block_rsv = &root->fs_info->delalloc_block_rsv; cow_start = (u64)-1; cur_offset = start; while (1) { ret = btrfs_lookup_file_extent(trans, root, path, ino, cur_offset, 0); BUG_ON(ret < 0); 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 = 0; next_slot: leaf = path->nodes[0]; if (path->slots[0] >= btrfs_header_nritems(leaf)) { ret = btrfs_next_leaf(root, path); if (ret < 0) BUG_ON(1); if (ret > 0) break; leaf = path->nodes[0]; } nocow = 0; disk_bytenr = 0; num_bytes = 0; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); if (found_key.objectid > ino || found_key.type > BTRFS_EXTENT_DATA_KEY || found_key.offset > end) break; if (found_key.offset > cur_offset) { extent_end = found_key.offset; extent_type = 0; goto out_check; } fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); extent_type = btrfs_file_extent_type(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); if (extent_end <= start) { path->slots[0]++; goto next_slot; } if (disk_bytenr == 0) goto out_check; 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_type == BTRFS_FILE_EXTENT_REG && !force) goto out_check; if (btrfs_extent_readonly(root, disk_bytenr)) goto out_check; if (btrfs_cross_ref_exist(trans, root, ino, found_key.offset - extent_offset, disk_bytenr)) goto out_check; disk_bytenr += extent_offset; disk_bytenr += cur_offset - found_key.offset; num_bytes = min(end + 1, extent_end) - cur_offset; /* * force cow if csum exists in the range. * this ensure that csum for a given extent are * either valid or do not exist. */ if (csum_exist_in_range(root, disk_bytenr, num_bytes)) goto out_check; nocow = 1; } else if (extent_type == BTRFS_FILE_EXTENT_INLINE) { extent_end = found_key.offset + btrfs_file_extent_inline_len(leaf, fi); extent_end = ALIGN(extent_end, root->sectorsize); } else { BUG_ON(1); } out_check: if (extent_end <= start) { path->slots[0]++; goto next_slot; } if (!nocow) { if (cow_start == (u64)-1) cow_start = cur_offset; cur_offset = extent_end; if (cur_offset > end) break; path->slots[0]++; goto next_slot; } btrfs_release_path(path); if (cow_start != (u64)-1) { ret = cow_file_range(inode, locked_page, cow_start, found_key.offset - 1, page_started, nr_written, 1); BUG_ON(ret); cow_start = (u64)-1; } if (extent_type == BTRFS_FILE_EXTENT_PREALLOC) { struct extent_map *em; struct extent_map_tree *em_tree; em_tree = &BTRFS_I(inode)->extent_tree; em = alloc_extent_map(); BUG_ON(!em); em->start = cur_offset; em->orig_start = em->start; em->len = num_bytes; em->block_len = num_bytes; em->block_start = disk_bytenr; em->bdev = root->fs_info->fs_devices->latest_bdev; set_bit(EXTENT_FLAG_PINNED, &em->flags); while (1) { write_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, em); write_unlock(&em_tree->lock); if (ret != -EEXIST) { free_extent_map(em); break; } btrfs_drop_extent_cache(inode, em->start, em->start + em->len - 1, 0); } type = BTRFS_ORDERED_PREALLOC; } else { type = BTRFS_ORDERED_NOCOW; } ret = btrfs_add_ordered_extent(inode, cur_offset, disk_bytenr, num_bytes, num_bytes, type); BUG_ON(ret); if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID) { ret = btrfs_reloc_clone_csums(inode, cur_offset, num_bytes); BUG_ON(ret); } extent_clear_unlock_delalloc(inode, &BTRFS_I(inode)->io_tree, cur_offset, cur_offset + num_bytes - 1, locked_page, EXTENT_CLEAR_UNLOCK_PAGE | EXTENT_CLEAR_UNLOCK | EXTENT_CLEAR_DELALLOC | EXTENT_SET_PRIVATE2); cur_offset = extent_end; 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) { ret = cow_file_range(inode, locked_page, cow_start, end, page_started, nr_written, 1); BUG_ON(ret); } if (nolock) { ret = btrfs_end_transaction_nolock(trans, root); BUG_ON(ret); } else { ret = btrfs_end_transaction(trans, root); BUG_ON(ret); } btrfs_free_path(path); return 0; } /* * extent_io.c call back to do delayed allocation processing */ static int run_delalloc_range(struct inode *inode, struct page *locked_page, u64 start, u64 end, int *page_started, unsigned long *nr_written) { int ret; struct btrfs_root *root = BTRFS_I(inode)->root; if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW) ret = run_delalloc_nocow(inode, locked_page, start, end, page_started, 1, nr_written); else if (BTRFS_I(inode)->flags & BTRFS_INODE_PREALLOC) ret = run_delalloc_nocow(inode, locked_page, start, end, page_started, 0, nr_written); else if (!btrfs_test_opt(root, COMPRESS) && !(BTRFS_I(inode)->force_compress) && !(BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS)) ret = cow_file_range(inode, locked_page, start, end, page_started, nr_written, 1); else ret = cow_file_range_async(inode, locked_page, start, end, page_started, nr_written); return ret; } static void btrfs_split_extent_hook(struct inode *inode, struct extent_state *orig, u64 split) { /* not delalloc, ignore it */ if (!(orig->state & EXTENT_DELALLOC)) return; spin_lock(&BTRFS_I(inode)->lock); BTRFS_I(inode)->outstanding_extents++; spin_unlock(&BTRFS_I(inode)->lock); } /* * extent_io.c merge_extent_hook, used to track 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. */ static void btrfs_merge_extent_hook(struct inode *inode, struct extent_state *new, struct extent_state *other) { /* not delalloc, ignore it */ if (!(other->state & EXTENT_DELALLOC)) return; spin_lock(&BTRFS_I(inode)->lock); BTRFS_I(inode)->outstanding_extents--; spin_unlock(&BTRFS_I(inode)->lock); } /* * extent_io.c set_bit_hook, used to track delayed allocation * bytes in this file, and to maintain the list of inodes that * have pending delalloc work to be done. */ static void btrfs_set_bit_hook(struct inode *inode, struct extent_state *state, int *bits) { /* * 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; bool do_list = !btrfs_is_free_space_inode(root, inode); if (*bits & EXTENT_FIRST_DELALLOC) { *bits &= ~EXTENT_FIRST_DELALLOC; } else { spin_lock(&BTRFS_I(inode)->lock); BTRFS_I(inode)->outstanding_extents++; spin_unlock(&BTRFS_I(inode)->lock); } spin_lock(&root->fs_info->delalloc_lock); BTRFS_I(inode)->delalloc_bytes += len; root->fs_info->delalloc_bytes += len; if (do_list && list_empty(&BTRFS_I(inode)->delalloc_inodes)) { list_add_tail(&BTRFS_I(inode)->delalloc_inodes, &root->fs_info->delalloc_inodes); } spin_unlock(&root->fs_info->delalloc_lock); } } /* * extent_io.c clear_bit_hook, see set_bit_hook for why */ static void btrfs_clear_bit_hook(struct inode *inode, struct extent_state *state, int *bits) { /* * 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; bool do_list = !btrfs_is_free_space_inode(root, inode); if (*bits & EXTENT_FIRST_DELALLOC) { *bits &= ~EXTENT_FIRST_DELALLOC; } else if (!(*bits & EXTENT_DO_ACCOUNTING)) { spin_lock(&BTRFS_I(inode)->lock); BTRFS_I(inode)->outstanding_extents--; spin_unlock(&BTRFS_I(inode)->lock); } if (*bits & EXTENT_DO_ACCOUNTING) btrfs_delalloc_release_metadata(inode, len); if (root->root_key.objectid != BTRFS_DATA_RELOC_TREE_OBJECTID && do_list) btrfs_free_reserved_data_space(inode, len); spin_lock(&root->fs_info->delalloc_lock); root->fs_info->delalloc_bytes -= len; BTRFS_I(inode)->delalloc_bytes -= len; if (do_list && BTRFS_I(inode)->delalloc_bytes == 0 && !list_empty(&BTRFS_I(inode)->delalloc_inodes)) { list_del_init(&BTRFS_I(inode)->delalloc_inodes); } spin_unlock(&root->fs_info->delalloc_lock); } } /* * extent_io.c merge_bio_hook, this must check the chunk tree to make sure * we don't create bios that span stripes or chunks */ int btrfs_merge_bio_hook(struct page *page, unsigned long offset, size_t size, struct bio *bio, unsigned long bio_flags) { struct btrfs_root *root = BTRFS_I(page->mapping->host)->root; struct btrfs_mapping_tree *map_tree; u64 logical = (u64)bio->bi_sector << 9; u64 length = 0; u64 map_length; int ret; if (bio_flags & EXTENT_BIO_COMPRESSED) return 0; length = bio->bi_size; map_tree = &root->fs_info->mapping_tree; map_length = length; ret = btrfs_map_block(map_tree, READ, logical, &map_length, NULL, 0); if (map_length < length + size) return 1; return ret; } /* * 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 int __btrfs_submit_bio_start(struct inode *inode, int rw, struct bio *bio, int mirror_num, unsigned long bio_flags, u64 bio_offset) { struct btrfs_root *root = BTRFS_I(inode)->root; int ret = 0; ret = btrfs_csum_one_bio(root, inode, bio, 0, 0); BUG_ON(ret); return 0; } /* * 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 int __btrfs_submit_bio_done(struct inode *inode, int rw, struct bio *bio, int mirror_num, unsigned long bio_flags, u64 bio_offset) { struct btrfs_root *root = BTRFS_I(inode)->root; return btrfs_map_bio(root, rw, bio, mirror_num, 1); } /* * 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 */ static int btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio, int mirror_num, unsigned long bio_flags, u64 bio_offset) { struct btrfs_root *root = BTRFS_I(inode)->root; int ret = 0; int skip_sum; skip_sum = BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM; if (btrfs_is_free_space_inode(root, inode)) ret = btrfs_bio_wq_end_io(root->fs_info, bio, 2); else ret = btrfs_bio_wq_end_io(root->fs_info, bio, 0); BUG_ON(ret); if (!(rw & REQ_WRITE)) { if (bio_flags & EXTENT_BIO_COMPRESSED) { return btrfs_submit_compressed_read(inode, bio, mirror_num, bio_flags); } else if (!skip_sum) { ret = btrfs_lookup_bio_sums(root, inode, bio, NULL); if (ret) return ret; } goto mapit; } else if (!skip_sum) { /* csum items have already been cloned */ if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID) goto mapit; /* we're doing a write, do the async checksumming */ return btrfs_wq_submit_bio(BTRFS_I(inode)->root->fs_info, inode, rw, bio, mirror_num, bio_flags, bio_offset, __btrfs_submit_bio_start, __btrfs_submit_bio_done); } mapit: return btrfs_map_bio(root, rw, bio, mirror_num, 0); } /* * 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 noinline int add_pending_csums(struct btrfs_trans_handle *trans, struct inode *inode, u64 file_offset, struct list_head *list) { struct btrfs_ordered_sum *sum; list_for_each_entry(sum, list, list) { btrfs_csum_file_blocks(trans, BTRFS_I(inode)->root->fs_info->csum_root, sum); } return 0; } int btrfs_set_extent_delalloc(struct inode *inode, u64 start, u64 end, struct extent_state **cached_state) { if ((end & (PAGE_CACHE_SIZE - 1)) == 0) WARN_ON(1); return set_extent_delalloc(&BTRFS_I(inode)->io_tree, start, end, cached_state, GFP_NOFS); } /* see btrfs_writepage_start_hook for details on why this is required */ struct btrfs_writepage_fixup { struct page *page; 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 page *page; struct inode *inode; u64 page_start; u64 page_end; fixup = container_of(work, struct btrfs_writepage_fixup, work); page = fixup->page; again: lock_page(page); if (!page->mapping || !PageDirty(page) || !PageChecked(page)) { ClearPageChecked(page); goto out_page; } inode = page->mapping->host; page_start = page_offset(page); page_end = page_offset(page) + PAGE_CACHE_SIZE - 1; lock_extent_bits(&BTRFS_I(inode)->io_tree, page_start, page_end, 0, &cached_state, GFP_NOFS); /* already ordered? We're done */ if (PagePrivate2(page)) goto out; ordered = btrfs_lookup_ordered_extent(inode, page_start); if (ordered) { unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end, &cached_state, GFP_NOFS); unlock_page(page); btrfs_start_ordered_extent(inode, ordered, 1); goto again; } BUG(); btrfs_set_extent_delalloc(inode, page_start, page_end, &cached_state); ClearPageChecked(page); out: unlock_extent_cached(&BTRFS_I(inode)->io_tree, page_start, page_end, &cached_state, GFP_NOFS); out_page: unlock_page(page); page_cache_release(page); kfree(fixup); } /* * 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. */ static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end) { struct inode *inode = page->mapping->host; struct btrfs_writepage_fixup *fixup; struct btrfs_root *root = BTRFS_I(inode)->root; /* this page is properly in the ordered list */ if (TestClearPagePrivate2(page)) return 0; if (PageChecked(page)) return -EAGAIN; fixup = kzalloc(sizeof(*fixup), GFP_NOFS); if (!fixup) return -EAGAIN; SetPageChecked(page); page_cache_get(page); fixup->work.func = btrfs_writepage_fixup_worker; fixup->page = page; btrfs_queue_worker(&root->fs_info->fixup_workers, &fixup->work); return -EAGAIN; } static int insert_reserved_file_extent(struct btrfs_trans_handle *trans, struct inode *inode, u64 file_pos, u64 disk_bytenr, u64 disk_num_bytes, u64 num_bytes, u64 ram_bytes, u8 compression, u8 encryption, u16 other_encoding, int extent_type) { struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_file_extent_item *fi; struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_key ins; u64 hint; int ret; path = btrfs_alloc_path(); if (!path) return -ENOMEM; path->leave_spinning = 1; /* * 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. */ ret = btrfs_drop_extents(trans, inode, file_pos, file_pos + num_bytes, &hint, 0); BUG_ON(ret); 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(*fi)); BUG_ON(ret); leaf = path->nodes[0]; fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); btrfs_set_file_extent_generation(leaf, fi, trans->transid); btrfs_set_file_extent_type(leaf, fi, extent_type); btrfs_set_file_extent_disk_bytenr(leaf, fi, disk_bytenr); btrfs_set_file_extent_disk_num_bytes(leaf, fi, disk_num_bytes); btrfs_set_file_extent_offset(leaf, fi, 0); btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes); btrfs_set_file_extent_ram_bytes(leaf, fi, ram_bytes); btrfs_set_file_extent_compression(leaf, fi, compression); btrfs_set_file_extent_encryption(leaf, fi, encryption); btrfs_set_file_extent_other_encoding(leaf, fi, other_encoding); btrfs_unlock_up_safe(path, 1); btrfs_set_lock_blocking(leaf); btrfs_mark_buffer_dirty(leaf); inode_add_bytes(inode, num_bytes); ins.objectid = disk_bytenr; ins.offset = disk_num_bytes; ins.type = BTRFS_EXTENT_ITEM_KEY; ret = btrfs_alloc_reserved_file_extent(trans, root, root->root_key.objectid, btrfs_ino(inode), file_pos, &ins); BUG_ON(ret); btrfs_free_path(path); return 0; } /* * helper function for btrfs_finish_ordered_io, this * just reads in some of the csum leaves to prime them into ram * before we start the transaction. It limits the amount of btree * reads required while inside the transaction. */ /* 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 inode *inode, u64 start, u64 end) { struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans = NULL; struct btrfs_ordered_extent *ordered_extent = NULL; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct extent_state *cached_state = NULL; int compress_type = 0; int ret; bool nolock; ret = btrfs_dec_test_ordered_pending(inode, &ordered_extent, start, end - start + 1); if (!ret) return 0; BUG_ON(!ordered_extent); nolock = btrfs_is_free_space_inode(root, inode); if (test_bit(BTRFS_ORDERED_NOCOW, &ordered_extent->flags)) { BUG_ON(!list_empty(&ordered_extent->list)); ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent); if (!ret) { if (nolock) trans = btrfs_join_transaction_nolock(root); else trans = btrfs_join_transaction(root); BUG_ON(IS_ERR(trans)); trans->block_rsv = &root->fs_info->delalloc_block_rsv; ret = btrfs_update_inode_fallback(trans, root, inode); BUG_ON(ret); } goto out; } lock_extent_bits(io_tree, ordered_extent->file_offset, ordered_extent->file_offset + ordered_extent->len - 1, 0, &cached_state, GFP_NOFS); if (nolock) trans = btrfs_join_transaction_nolock(root); else trans = btrfs_join_transaction(root); BUG_ON(IS_ERR(trans)); trans->block_rsv = &root->fs_info->delalloc_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 + ordered_extent->len); BUG_ON(ret); } else { BUG_ON(root == root->fs_info->tree_root); ret = insert_reserved_file_extent(trans, inode, ordered_extent->file_offset, ordered_extent->start, ordered_extent->disk_len, ordered_extent->len, ordered_extent->len, compress_type, 0, 0, BTRFS_FILE_EXTENT_REG); unpin_extent_cache(&BTRFS_I(inode)->extent_tree, ordered_extent->file_offset, ordered_extent->len); BUG_ON(ret); } unlock_extent_cached(io_tree, ordered_extent->file_offset, ordered_extent->file_offset + ordered_extent->len - 1, &cached_state, GFP_NOFS); add_pending_csums(trans, inode, ordered_extent->file_offset, &ordered_extent->list); ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent); if (!ret || !test_bit(BTRFS_ORDERED_PREALLOC, &ordered_extent->flags)) { ret = btrfs_update_inode_fallback(trans, root, inode); BUG_ON(ret); } ret = 0; out: if (root != root->fs_info->tree_root) btrfs_delalloc_release_metadata(inode, ordered_extent->len); if (trans) { if (nolock) btrfs_end_transaction_nolock(trans, root); else btrfs_end_transaction(trans, root); } /* once for us */ btrfs_put_ordered_extent(ordered_extent); /* once for the tree */ btrfs_put_ordered_extent(ordered_extent); return 0; } static int btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end, struct extent_state *state, int uptodate) { trace_btrfs_writepage_end_io_hook(page, start, end, uptodate); ClearPagePrivate2(page); return btrfs_finish_ordered_io(page->mapping->host, start, end); } /* * when reads are done, we need to check csums to verify the data is correct * if there's a match, we allow the bio to finish. If not, the code in * extent_io.c will try to find good copies for us. */ static int btrfs_readpage_end_io_hook(struct page *page, u64 start, u64 end, struct extent_state *state) { size_t offset = start - ((u64)page->index << PAGE_CACHE_SHIFT); struct inode *inode = page->mapping->host; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; char *kaddr; u64 private = ~(u32)0; int ret; struct btrfs_root *root = BTRFS_I(inode)->root; u32 csum = ~(u32)0; if (PageChecked(page)) { ClearPageChecked(page); goto good; } if (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM) goto good; if (root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID && test_range_bit(io_tree, start, end, EXTENT_NODATASUM, 1, NULL)) { clear_extent_bits(io_tree, start, end, EXTENT_NODATASUM, GFP_NOFS); return 0; } if (state && state->start == start) { private = state->private; ret = 0; } else { ret = get_state_private(io_tree, start, &private); } kaddr = kmap_atomic(page, KM_USER0); if (ret) goto zeroit; csum = btrfs_csum_data(root, kaddr + offset, csum, end - start + 1); btrfs_csum_final(csum, (char *)&csum); if (csum != private) goto zeroit; kunmap_atomic(kaddr, KM_USER0); good: return 0; zeroit: printk_ratelimited(KERN_INFO "btrfs csum failed ino %llu off %llu csum %u " "private %llu\n", (unsigned long long)btrfs_ino(page->mapping->host), (unsigned long long)start, csum, (unsigned long long)private); memset(kaddr + offset, 1, end - start + 1); flush_dcache_page(page); kunmap_atomic(kaddr, KM_USER0); if (private == 0) return 0; return -EIO; } struct delayed_iput { struct list_head list; struct inode *inode; }; void btrfs_add_delayed_iput(struct inode *inode) { struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info; struct delayed_iput *delayed; if (atomic_add_unless(&inode->i_count, -1, 1)) return; delayed = kmalloc(sizeof(*delayed), GFP_NOFS | __GFP_NOFAIL); delayed->inode = inode; spin_lock(&fs_info->delayed_iput_lock); list_add_tail(&delayed->list, &fs_info->delayed_iputs); spin_unlock(&fs_info->delayed_iput_lock); } void btrfs_run_delayed_iputs(struct btrfs_root *root) { LIST_HEAD(list); struct btrfs_fs_info *fs_info = root->fs_info; struct delayed_iput *delayed; int empty; spin_lock(&fs_info->delayed_iput_lock); empty = list_empty(&fs_info->delayed_iputs); spin_unlock(&fs_info->delayed_iput_lock); if (empty) return; down_read(&root->fs_info->cleanup_work_sem); spin_lock(&fs_info->delayed_iput_lock); list_splice_init(&fs_info->delayed_iputs, &list); spin_unlock(&fs_info->delayed_iput_lock); while (!list_empty(&list)) { delayed = list_entry(list.next, struct delayed_iput, list); list_del(&delayed->list); iput(delayed->inode); kfree(delayed); } up_read(&root->fs_info->cleanup_work_sem); } enum btrfs_orphan_cleanup_state { ORPHAN_CLEANUP_STARTED = 1, ORPHAN_CLEANUP_DONE = 2, }; /* * This is called in transaction commmit time. If there are no orphan * files in the subvolume, it removes orphan item and frees block_rsv * structure. */ void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans, struct btrfs_root *root) { int ret; if (!list_empty(&root->orphan_list) || root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE) return; if (root->orphan_item_inserted && btrfs_root_refs(&root->root_item) > 0) { ret = btrfs_del_orphan_item(trans, root->fs_info->tree_root, root->root_key.objectid); BUG_ON(ret); root->orphan_item_inserted = 0; } if (root->orphan_block_rsv) { WARN_ON(root->orphan_block_rsv->size > 0); btrfs_free_block_rsv(root, root->orphan_block_rsv); root->orphan_block_rsv = NULL; } } /* * This creates an orphan entry for the given inode in case something goes * wrong in the middle of an unlink/truncate. * * NOTE: caller of this function should reserve 5 units of metadata for * this function. */ int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode) { struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_block_rsv *block_rsv = NULL; int reserve = 0; int insert = 0; int ret; if (!root->orphan_block_rsv) { block_rsv = btrfs_alloc_block_rsv(root); if (!block_rsv) return -ENOMEM; } spin_lock(&root->orphan_lock); if (!root->orphan_block_rsv) { root->orphan_block_rsv = block_rsv; } else if (block_rsv) { btrfs_free_block_rsv(root, block_rsv); block_rsv = NULL; } if (list_empty(&BTRFS_I(inode)->i_orphan)) { list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list); #if 0 /* * For proper ENOSPC handling, we should do orphan * cleanup when mounting. But this introduces backward * compatibility issue. */ if (!xchg(&root->orphan_item_inserted, 1)) insert = 2; else insert = 1; #endif insert = 1; } if (!BTRFS_I(inode)->orphan_meta_reserved) { BTRFS_I(inode)->orphan_meta_reserved = 1; reserve = 1; } spin_unlock(&root->orphan_lock); /* grab metadata reservation from transaction handle */ if (reserve) { ret = btrfs_orphan_reserve_metadata(trans, inode); BUG_ON(ret); } /* insert an orphan item to track this unlinked/truncated file */ if (insert >= 1) { ret = btrfs_insert_orphan_item(trans, root, btrfs_ino(inode)); BUG_ON(ret); } /* insert an orphan item to track subvolume contains orphan files */ if (insert >= 2) { ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root, root->root_key.objectid); BUG_ON(ret); } return 0; } /* * We have done the truncate/delete so we can go ahead and remove the orphan * item for this particular inode. */ int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode) { struct btrfs_root *root = BTRFS_I(inode)->root; int delete_item = 0; int release_rsv = 0; int ret = 0; spin_lock(&root->orphan_lock); if (!list_empty(&BTRFS_I(inode)->i_orphan)) { list_del_init(&BTRFS_I(inode)->i_orphan); delete_item = 1; } if (BTRFS_I(inode)->orphan_meta_reserved) { BTRFS_I(inode)->orphan_meta_reserved = 0; release_rsv = 1; } spin_unlock(&root->orphan_lock); if (trans && delete_item) { ret = btrfs_del_orphan_item(trans, root, btrfs_ino(inode)); BUG_ON(ret); } if (release_rsv) btrfs_orphan_release_metadata(inode); return 0; } /* * this cleans up any orphans that may be left on the list from the last use * of this root. */ int btrfs_orphan_cleanup(struct btrfs_root *root) { struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_key key, found_key; struct btrfs_trans_handle *trans; struct inode *inode; u64 last_objectid = 0; int ret = 0, nr_unlink = 0, nr_truncate = 0; if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED)) return 0; path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } path->reada = -1; key.objectid = BTRFS_ORPHAN_OBJECTID; btrfs_set_key_type(&key, BTRFS_ORPHAN_ITEM_KEY); key.offset = (u64)-1; while (1) { ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); if (ret < 0) goto out; /* * if ret == 0 means we found what we were searching for, which * is weird, but possible, so only screw with path if we didn't * find the key and see if we have stuff that matches */ if (ret > 0) { ret = 0; if (path->slots[0] == 0) break; path->slots[0]--; } /* pull out the item */ leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); /* make sure the item matches what we want */ if (found_key.objectid != BTRFS_ORPHAN_OBJECTID) break; if (btrfs_key_type(&found_key) != BTRFS_ORPHAN_ITEM_KEY) break; /* release the path since we're done with it */ btrfs_release_path(path); /* * this is where we are basically btrfs_lookup, without the * crossing root thing. we store the inode number in the * offset of the orphan item. */ if (found_key.offset == last_objectid) { printk(KERN_ERR "btrfs: Error removing orphan entry, " "stopping orphan cleanup\n"); ret = -EINVAL; goto out; } last_objectid = found_key.offset; found_key.objectid = found_key.offset; found_key.type = BTRFS_INODE_ITEM_KEY; found_key.offset = 0; inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL); ret = PTR_RET(inode); if (ret && ret != -ESTALE) goto out; /* * Inode is already gone but the orphan item is still there, * kill the orphan item. */ if (ret == -ESTALE) { trans = btrfs_start_transaction(root, 1); if (IS_ERR(trans)) { ret = PTR_ERR(trans); goto out; } ret = btrfs_del_orphan_item(trans, root, found_key.objectid); BUG_ON(ret); btrfs_end_transaction(trans, root); continue; } /* * add this inode to the orphan list so btrfs_orphan_del does * the proper thing when we hit it */ spin_lock(&root->orphan_lock); list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list); spin_unlock(&root->orphan_lock); /* if we have links, this was a truncate, lets do that */ if (inode->i_nlink) { if (!S_ISREG(inode->i_mode)) { WARN_ON(1); iput(inode); continue; } nr_truncate++; ret = btrfs_truncate(inode); } else { nr_unlink++; } /* this will do delete_inode and everything for us */ iput(inode); if (ret) goto out; } /* release the path since we're done with it */ btrfs_release_path(path); root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE; if (root->orphan_block_rsv) btrfs_block_rsv_release(root, root->orphan_block_rsv, (u64)-1); if (root->orphan_block_rsv || root->orphan_item_inserted) { trans = btrfs_join_transaction(root); if (!IS_ERR(trans)) btrfs_end_transaction(trans, root); } if (nr_unlink) printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink); if (nr_truncate) printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate); out: if (ret) printk(KERN_CRIT "btrfs: could not do orphan cleanup %d\n", ret); btrfs_free_path(path); return ret; } /* * very simple check to peek ahead in the leaf looking for xattrs. If we * don't find any xattrs, we know there can't be any acls. * * slot is the slot the inode is in, objectid is the objectid of the inode */ static noinline int acls_after_inode_item(struct extent_buffer *leaf, int slot, u64 objectid) { u32 nritems = btrfs_header_nritems(leaf); struct btrfs_key found_key; int scanned = 0; slot++; while (slot < nritems) { btrfs_item_key_to_cpu(leaf, &found_key, slot); /* we found a different objectid, there must not be acls */ if (found_key.objectid != objectid) return 0; /* we found an xattr, assume we've got an acl */ if (found_key.type == BTRFS_XATTR_ITEM_KEY) return 1; /* * we found a key greater than an xattr key, there can't * be any acls later on */ if (found_key.type > BTRFS_XATTR_ITEM_KEY) return 0; slot++; scanned++; /* * it goes inode, inode backrefs, xattrs, extents, * so if there are a ton of hard links to an inode there can * be a lot of backrefs. Don't waste time searching too hard, * this is just an optimization */ if (scanned >= 8) break; } /* we hit the end of the leaf before we found an xattr or * something larger than an xattr. We have to assume the inode * has acls */ return 1; } /* * read an inode from the btree into the in-memory inode */ static void btrfs_read_locked_inode(struct inode *inode) { struct btrfs_path *path; struct extent_buffer *leaf; struct btrfs_inode_item *inode_item; struct btrfs_timespec *tspec; struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_key location; int maybe_acls; u32 rdev; int ret; bool filled = false; ret = btrfs_fill_inode(inode, &rdev); if (!ret) filled = true; path =