diff options
| -rw-r--r-- | fs/btrfs/ctree.h | 4 | ||||
| -rw-r--r-- | fs/btrfs/extent-tree.c | 2 | ||||
| -rw-r--r-- | fs/btrfs/file.c | 332 | ||||
| -rw-r--r-- | fs/btrfs/inode.c | 28 | ||||
| -rw-r--r-- | fs/btrfs/tree-log.c | 2 |
5 files changed, 355 insertions, 13 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 71d6ff13d76e..88adfe638409 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -3250,6 +3250,8 @@ int btrfs_unlink_subvol(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *dir, u64 objectid, const char *name, int name_len); +int btrfs_truncate_page(struct inode *inode, loff_t from, loff_t len, + int front); int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode, u64 new_size, @@ -3323,7 +3325,7 @@ extern const struct file_operations btrfs_file_operations; int __btrfs_drop_extents(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode, struct btrfs_path *path, u64 start, u64 end, - int drop_cache); + u64 *drop_end, int drop_cache); int btrfs_drop_extents(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode, u64 start, u64 end, int drop_cache); diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index df2f17b0ac5d..ee51b7afe97d 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -4132,6 +4132,8 @@ struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_root *root) void btrfs_free_block_rsv(struct btrfs_root *root, struct btrfs_block_rsv *rsv) { + if (!rsv) + return; btrfs_block_rsv_release(root, rsv, (u64)-1); kfree(rsv); } diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 58598c249951..57026a6e9c94 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -39,6 +39,7 @@ #include "tree-log.h" #include "locking.h" #include "compat.h" +#include "volumes.h" /* * when auto defrag is enabled we @@ -584,7 +585,7 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, int __btrfs_drop_extents(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct inode *inode, struct btrfs_path *path, u64 start, u64 end, - int drop_cache) + u64 *drop_end, int drop_cache) { struct extent_buffer *leaf; struct btrfs_file_extent_item *fi; @@ -822,6 +823,8 @@ next_slot: btrfs_abort_transaction(trans, root, ret); } + if (drop_end) + *drop_end = min(end, extent_end); btrfs_release_path(path); return ret; } @@ -836,7 +839,7 @@ int btrfs_drop_extents(struct btrfs_trans_handle *trans, path = btrfs_alloc_path(); if (!path) return -ENOMEM; - ret = __btrfs_drop_extents(trans, root, inode, path, start, end, + ret = __btrfs_drop_extents(trans, root, inode, path, start, end, NULL, drop_cache); btrfs_free_path(path); return ret; @@ -1645,6 +1648,324 @@ static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma) return 0; } +static int hole_mergeable(struct inode *inode, struct extent_buffer *leaf, + int slot, u64 start, u64 end) +{ + struct btrfs_file_extent_item *fi; + struct btrfs_key key; + + if (slot < 0 || slot >= btrfs_header_nritems(leaf)) + return 0; + + btrfs_item_key_to_cpu(leaf, &key, slot); + if (key.objectid != btrfs_ino(inode) || + key.type != BTRFS_EXTENT_DATA_KEY) + return 0; + + fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); + + if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG) + return 0; + + if (btrfs_file_extent_disk_bytenr(leaf, fi)) + return 0; + + if (key.offset == end) + return 1; + if (key.offset + btrfs_file_extent_num_bytes(leaf, fi) == start) + return 1; + return 0; +} + +static int fill_holes(struct btrfs_trans_handle *trans, struct inode *inode, + struct btrfs_path *path, u64 offset, u64 end) +{ + struct btrfs_root *root = BTRFS_I(inode)->root; + struct extent_buffer *leaf; + struct btrfs_file_extent_item *fi; + struct extent_map *hole_em; + struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; + struct btrfs_key key; + int ret; + + key.objectid = btrfs_ino(inode); + key.type = BTRFS_EXTENT_DATA_KEY; + key.offset = offset; + + + ret = btrfs_search_slot(trans, root, &key, path, 0, 1); + if (ret < 0) + return ret; + BUG_ON(!ret); + + leaf = path->nodes[0]; + if (hole_mergeable(inode, leaf, path->slots[0]-1, offset, end)) { + u64 num_bytes; + + path->slots[0]--; + fi = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_file_extent_item); + num_bytes = btrfs_file_extent_num_bytes(leaf, fi) + + end - offset; + btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes); + btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes); + btrfs_set_file_extent_offset(leaf, fi, 0); + btrfs_mark_buffer_dirty(leaf); + goto out; + } + + if (hole_mergeable(inode, leaf, path->slots[0]+1, offset, end)) { + u64 num_bytes; + + path->slots[0]++; + key.offset = offset; + btrfs_set_item_key_safe(trans, root, path, &key); + fi = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_file_extent_item); + num_bytes = btrfs_file_extent_num_bytes(leaf, fi) + end - + offset; + btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes); + btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes); + btrfs_set_file_extent_offset(leaf, fi, 0); + btrfs_mark_buffer_dirty(leaf); + goto out; + } + btrfs_release_path(path); + + ret = btrfs_insert_file_extent(trans, root, btrfs_ino(inode), offset, + 0, 0, end - offset, 0, end - offset, + 0, 0, 0); + if (ret) + return ret; + +out: + btrfs_release_path(path); + + hole_em = alloc_extent_map(); + if (!hole_em) { + btrfs_drop_extent_cache(inode, offset, end - 1, 0); + set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, + &BTRFS_I(inode)->runtime_flags); + } else { + hole_em->start = offset; + hole_em->len = end - offset; + hole_em->orig_start = offset; + + hole_em->block_start = EXTENT_MAP_HOLE; + hole_em->block_len = 0; + hole_em->bdev = root->fs_info->fs_devices->latest_bdev; + hole_em->compress_type = BTRFS_COMPRESS_NONE; + hole_em->generation = trans->transid; + + do { + btrfs_drop_extent_cache(inode, offset, end - 1, 0); + write_lock(&em_tree->lock); + ret = add_extent_mapping(em_tree, hole_em); + if (!ret) + list_move(&hole_em->list, + &em_tree->modified_extents); + write_unlock(&em_tree->lock); + } while (ret == -EEXIST); + free_extent_map(hole_em); + if (ret) + set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, + &BTRFS_I(inode)->runtime_flags); + } + + return 0; +} + +static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len) +{ + struct btrfs_root *root = BTRFS_I(inode)->root; + struct extent_state *cached_state = NULL; + struct btrfs_path *path; + struct btrfs_block_rsv *rsv; + struct btrfs_trans_handle *trans; + u64 mask = BTRFS_I(inode)->root->sectorsize - 1; + u64 lockstart = (offset + mask) & ~mask; + u64 lockend = ((offset + len) & ~mask) - 1; + u64 cur_offset = lockstart; + u64 min_size = btrfs_calc_trunc_metadata_size(root, 1); + u64 drop_end; + unsigned long nr; + int ret = 0; + int err = 0; + bool same_page = (offset >> PAGE_CACHE_SHIFT) == + ((offset + len) >> PAGE_CACHE_SHIFT); + + btrfs_wait_ordered_range(inode, offset, len); + + mutex_lock(&inode->i_mutex); + if (offset >= inode->i_size) { + mutex_unlock(&inode->i_mutex); + return 0; + } + + /* + * Only do this if we are in the same page and we aren't doing the + * entire page. + */ + if (same_page && len < PAGE_CACHE_SIZE) { + ret = btrfs_truncate_page(inode, offset, len, 0); + mutex_unlock(&inode->i_mutex); + return ret; + } + + /* zero back part of the first page */ + ret = btrfs_truncate_page(inode, offset, 0, 0); + if (ret) { + mutex_unlock(&inode->i_mutex); + return ret; + } + + /* zero the front end of the last page */ + ret = btrfs_truncate_page(inode, offset + len, 0, 1); + if (ret) { + mutex_unlock(&inode->i_mutex); + return ret; + } + + if (lockend < lockstart) { + mutex_unlock(&inode->i_mutex); + return 0; + } + + while (1) { + struct btrfs_ordered_extent *ordered; + + truncate_pagecache_range(inode, lockstart, lockend); + + lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, + 0, &cached_state); + ordered = btrfs_lookup_first_ordered_extent(inode, lockend); + + /* + * We need to make sure we have no ordered extents in this range + * and nobody raced in and read a page in this range, if we did + * we need to try again. + */ + if ((!ordered || + (ordered->file_offset + ordered->len < lockstart || + ordered->file_offset > lockend)) && + !test_range_bit(&BTRFS_I(inode)->io_tree, lockstart, + lockend, EXTENT_UPTODATE, 0, + cached_state)) { + if (ordered) + btrfs_put_ordered_extent(ordered); + break; + } + if (ordered) + btrfs_put_ordered_extent(ordered); + unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, + lockend, &cached_state, GFP_NOFS); + btrfs_wait_ordered_range(inode, lockstart, + lockend - lockstart + 1); + } + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + + rsv = btrfs_alloc_block_rsv(root); + if (!rsv) { + ret = -ENOMEM; + goto out_free; + } + rsv->size = btrfs_calc_trunc_metadata_size(root, 1); + rsv->failfast = 1; + + /* + * 1 - update the inode + * 1 - removing the extents in the range + * 1 - adding the hole extent + */ + trans = btrfs_start_transaction(root, 3); + if (IS_ERR(trans)) { + err = PTR_ERR(trans); + goto out_free; + } + + ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, rsv, + min_size); + BUG_ON(ret); + trans->block_rsv = rsv; + + while (cur_offset < lockend) { + ret = __btrfs_drop_extents(trans, root, inode, path, + cur_offset, lockend + 1, + &drop_end, 1); + if (ret != -ENOSPC) + break; + + trans->block_rsv = &root->fs_info->trans_block_rsv; + + ret = fill_holes(trans, inode, path, cur_offset, drop_end); + if (ret) { + err = ret; + break; + } + + cur_offset = drop_end; + + ret = btrfs_update_inode(trans, root, inode); + if (ret) { + err = ret; + break; + } + + nr = trans->blocks_used; + btrfs_end_transaction(trans, root); + btrfs_btree_balance_dirty(root, nr); + + trans = btrfs_start_transaction(root, 3); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + trans = NULL; + break; + } + + ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, + rsv, min_size); + BUG_ON(ret); /* shouldn't happen */ + trans->block_rsv = rsv; + } + + if (ret) { + err = ret; + goto out_trans; + } + + trans->block_rsv = &root->fs_info->trans_block_rsv; + ret = fill_holes(trans, inode, path, cur_offset, drop_end); + if (ret) { + err = ret; + goto out_trans; + } + +out_trans: + if (!trans) + goto out_free; + + trans->block_rsv = &root->fs_info->trans_block_rsv; + ret = btrfs_update_inode(trans, root, inode); + nr = trans->blocks_used; + btrfs_end_transaction(trans, root); + btrfs_btree_balance_dirty(root, nr); +out_free: + btrfs_free_path(path); + btrfs_free_block_rsv(root, rsv); +out: + unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, + &cached_state, GFP_NOFS); + mutex_unlock(&inode->i_mutex); + if (ret && !err) + err = ret; + return err; +} + static long btrfs_fallocate(struct file *file, int mode, loff_t offset, loff_t len) { @@ -1663,10 +1984,13 @@ static long btrfs_fallocate(struct file *file, int mode, alloc_start = offset & ~mask; alloc_end = (offset + len + mask) & ~mask; - /* We only support the FALLOC_FL_KEEP_SIZE mode */ - if (mode & ~FALLOC_FL_KEEP_SIZE) + /* Make sure we aren't being give some crap mode */ + if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE)) return -EOPNOTSUPP; + if (mode & FALLOC_FL_PUNCH_HOLE) + return btrfs_punch_hole(inode, offset, len); + /* * Make sure we have enough space before we do the * allocation. diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index f0a4792492ed..8cb272c84089 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -3475,12 +3475,20 @@ error: } /* - * taken from block_truncate_page, but does cow as it zeros out - * any bytes left in the last page in the file. + * btrfs_truncate_page - read, zero a chunk and write a page + * @inode - inode that we're zeroing + * @from - the offset to start zeroing + * @len - the length to zero, 0 to zero the entire range respective to the + * offset + * @front - zero up to the offset instead of from the offset on + * + * This will find the page for the "from" offset and cow the page and zero the + * part we want to zero. This is used with truncate and hole punching. */ -static int btrfs_truncate_page(struct address_space *mapping, loff_t from) +int btrfs_truncate_page(struct inode *inode, loff_t from, loff_t len, + int front) { - struct inode *inode = mapping->host; + struct address_space *mapping = inode->i_mapping; struct btrfs_root *root = BTRFS_I(inode)->root; struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; struct btrfs_ordered_extent *ordered; @@ -3495,7 +3503,8 @@ static int btrfs_truncate_page(struct address_space *mapping, loff_t from) u64 page_start; u64 page_end; - if ((offset & (blocksize - 1)) == 0) + if ((offset & (blocksize - 1)) == 0 && + (!len || ((len & (blocksize - 1)) == 0))) goto out; ret = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE); if (ret) @@ -3555,8 +3564,13 @@ again: ret = 0; if (offset != PAGE_CACHE_SIZE) { + if (!len) + len = PAGE_CACHE_SIZE - offset; kaddr = kmap(page); - memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset); + if (front) + memset(kaddr, 0, offset); + else + memset(kaddr + offset, 0, len); flush_dcache_page(page); kunmap(page); } @@ -6796,7 +6810,7 @@ static int btrfs_truncate(struct inode *inode) u64 mask = root->sectorsize - 1; u64 min_size = btrfs_calc_trunc_metadata_size(root, 1); - ret = btrfs_truncate_page(inode->i_mapping, inode->i_size); + ret = btrfs_truncate_page(inode, inode->i_size, 0, 0); if (ret) return ret; diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 0c39f58973db..f9b0fc911661 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -2842,7 +2842,7 @@ static int log_one_extent(struct btrfs_trans_handle *trans, if (BTRFS_I(inode)->logged_trans == trans->transid) { ret = __btrfs_drop_extents(trans, log, inode, dst_path, start, - start + len, 0); + start + len, NULL, 0); if (ret) return ret; } |