From b18c6685810af8e6763760711aece31ccc7a8ea8 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Tue, 17 Apr 2007 13:26:50 -0400 Subject: [PATCH] Btrfs: progress on file_write Signed-off-by: Chris Mason --- fs/btrfs/ctree.c | 57 +++++++++ fs/btrfs/ctree.h | 21 ++- fs/btrfs/extent-tree.c | 20 +-- fs/btrfs/file-item.c | 61 ++++++--- fs/btrfs/super.c | 284 ++++++++++++++++++++++++++++++++++++++--- 5 files changed, 394 insertions(+), 49 deletions(-) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 6b76fd967153..43d4779abdd1 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -1249,6 +1249,63 @@ static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root return ret; } +int btrfs_truncate_item(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + u32 new_size) +{ + int ret = 0; + int slot; + int slot_orig; + struct btrfs_leaf *leaf; + struct buffer_head *leaf_buf; + u32 nritems; + unsigned int data_end; + unsigned int old_data_start; + unsigned int old_size; + unsigned int size_diff; + int i; + + slot_orig = path->slots[0]; + leaf_buf = path->nodes[0]; + leaf = btrfs_buffer_leaf(leaf_buf); + + nritems = btrfs_header_nritems(&leaf->header); + data_end = leaf_data_end(root, leaf); + + slot = path->slots[0]; + old_data_start = btrfs_item_offset(leaf->items + slot); + old_size = btrfs_item_size(leaf->items + slot); + BUG_ON(old_size <= new_size); + size_diff = old_size - new_size; + + BUG_ON(slot < 0); + BUG_ON(slot >= nritems); + + /* + * item0..itemN ... dataN.offset..dataN.size .. data0.size + */ + /* first correct the data pointers */ + for (i = slot; i < nritems; i++) { + u32 ioff = btrfs_item_offset(leaf->items + i); + btrfs_set_item_offset(leaf->items + i, + ioff + size_diff); + } + /* shift the data */ +printk("truncate item, new_size %u old_size %u, diff %u, bufp %p, dst, %p, num %u, old_data_start %u, data_end %u\n", new_size, old_size, size_diff, leaf, btrfs_leaf_data(leaf) + data_end + size_diff, old_data_start-data_end, old_data_start, data_end); + btrfs_memmove(root, leaf, btrfs_leaf_data(leaf) + + data_end + size_diff, btrfs_leaf_data(leaf) + + data_end, old_data_start + new_size - data_end); + btrfs_set_item_size(leaf->items + slot, new_size); + btrfs_mark_buffer_dirty(leaf_buf); + + ret = 0; + if (btrfs_leaf_free_space(root, leaf) < 0) + BUG(); + check_leaf(root, path, 0); + return ret; +} + int btrfs_extend_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u32 data_size) { diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 796f19d03ab5..ca3ab160f460 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -999,7 +999,7 @@ static inline void btrfs_mark_buffer_dirty(struct buffer_head *bh) ((type *)(btrfs_leaf_data(leaf) + \ btrfs_item_offset((leaf)->items + (slot)))) -/* extent-item.c */ +/* extent-tree.c */ int btrfs_inc_root_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root); struct buffer_head *btrfs_alloc_free_block(struct btrfs_trans_handle *trans, @@ -1013,9 +1013,16 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 blocknr, u64 num_blocks, int pin); int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, struct btrfs_root *root); +int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 blocknr, u64 num_blocks); /* ctree.c */ int btrfs_extend_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u32 data_size); +int btrfs_truncate_item(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + u32 new_size); int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_key *key, struct btrfs_path *p, int ins_len, int cow); @@ -1073,11 +1080,10 @@ int btrfs_lookup_inode(struct btrfs_trans_handle *trans, struct btrfs_root struct btrfs_key *location, int mod); /* file-item.c */ -int btrfs_alloc_file_extent(struct btrfs_trans_handle *trans, +int btrfs_insert_file_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root, - u64 objectid, u64 offset, - u64 num_blocks, u64 hint_block, - u64 *result); + u64 objectid, u64 pos, u64 offset, + u64 num_blocks); int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, u64 objectid, @@ -1090,6 +1096,11 @@ int btrfs_csum_file_block(struct btrfs_trans_handle *trans, int btrfs_csum_verify_file_block(struct btrfs_root *root, u64 objectid, u64 offset, char *data, size_t len); +struct btrfs_csum_item *btrfs_lookup_csum(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + u64 objectid, u64 offset, + int cow); /* super.c */ extern struct subsystem btrfs_subsys; diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index d560831c10a7..2cee9df001f6 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -12,8 +12,9 @@ static int finish_current_insert(struct btrfs_trans_handle *trans, struct static int del_pending_extents(struct btrfs_trans_handle *trans, struct btrfs_root *extent_root); -static int inc_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root - *root, u64 blocknr, u64 num_blocks) +int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + u64 blocknr, u64 num_blocks) { struct btrfs_path *path; int ret; @@ -50,8 +51,9 @@ static int inc_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root return 0; } -static int lookup_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root - *root, u64 blocknr, u64 num_blocks, u32 *refs) +static int lookup_extent_ref(struct btrfs_trans_handle *trans, + struct btrfs_root *root, u64 blocknr, + u64 num_blocks, u32 *refs) { struct btrfs_path *path; int ret; @@ -80,7 +82,7 @@ static int lookup_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root int btrfs_inc_root_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root) { - return inc_block_ref(trans, root, bh_blocknr(root->node), 1); + return btrfs_inc_extent_ref(trans, root, bh_blocknr(root->node), 1); } int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, @@ -107,13 +109,13 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, continue; fi = btrfs_item_ptr(buf_leaf, i, struct btrfs_file_extent_item); - ret = inc_block_ref(trans, root, + ret = btrfs_inc_extent_ref(trans, root, btrfs_file_extent_disk_blocknr(fi), btrfs_file_extent_disk_num_blocks(fi)); BUG_ON(ret); } else { blocknr = btrfs_node_blockptr(buf_node, i); - ret = inc_block_ref(trans, root, blocknr, 1); + ret = btrfs_inc_extent_ref(trans, root, blocknr, 1); BUG_ON(ret); } } @@ -563,7 +565,7 @@ static int walk_down_tree(struct btrfs_trans_handle *trans, struct btrfs_root WARN_ON(*level < 0); WARN_ON(*level >= BTRFS_MAX_LEVEL); - ret = lookup_block_ref(trans, root, bh_blocknr(path->nodes[*level]), + ret = lookup_extent_ref(trans, root, bh_blocknr(path->nodes[*level]), 1, &refs); BUG_ON(ret); if (refs > 1) @@ -587,7 +589,7 @@ static int walk_down_tree(struct btrfs_trans_handle *trans, struct btrfs_root } blocknr = btrfs_node_blockptr(btrfs_buffer_node(cur), path->slots[*level]); - ret = lookup_block_ref(trans, root, blocknr, 1, &refs); + ret = lookup_extent_ref(trans, root, blocknr, 1, &refs); BUG_ON(ret); if (refs != 1) { path->slots[*level]++; diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c index 93d42d650820..f49968ad0a07 100644 --- a/fs/btrfs/file-item.c +++ b/fs/btrfs/file-item.c @@ -6,13 +6,11 @@ #define MAX_CSUM_ITEMS(r) ((((BTRFS_LEAF_DATA_SIZE(r) - \ sizeof(struct btrfs_item)) / \ sizeof(struct btrfs_csum_item)) - 1)) -int btrfs_alloc_file_extent(struct btrfs_trans_handle *trans, +int btrfs_insert_file_extent(struct btrfs_trans_handle *trans, struct btrfs_root *root, - u64 objectid, u64 offset, - u64 num_blocks, u64 hint_block, - u64 *result) + u64 objectid, u64 pos, + u64 offset, u64 num_blocks) { - struct btrfs_key ins; int ret = 0; struct btrfs_file_extent_item *item; struct btrfs_key file_key; @@ -21,11 +19,13 @@ int btrfs_alloc_file_extent(struct btrfs_trans_handle *trans, path = btrfs_alloc_path(); BUG_ON(!path); btrfs_init_path(path); + /* ret = btrfs_alloc_extent(trans, root, num_blocks, hint_block, (u64)-1, &ins); + */ BUG_ON(ret); file_key.objectid = objectid; - file_key.offset = offset; + file_key.offset = pos; file_key.flags = 0; btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY); @@ -34,21 +34,22 @@ int btrfs_alloc_file_extent(struct btrfs_trans_handle *trans, BUG_ON(ret); item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0], struct btrfs_file_extent_item); - btrfs_set_file_extent_disk_blocknr(item, ins.objectid); - btrfs_set_file_extent_disk_num_blocks(item, ins.offset); + btrfs_set_file_extent_disk_blocknr(item, offset); + btrfs_set_file_extent_disk_num_blocks(item, num_blocks); btrfs_set_file_extent_offset(item, 0); - btrfs_set_file_extent_num_blocks(item, ins.offset); + btrfs_set_file_extent_num_blocks(item, num_blocks); btrfs_set_file_extent_generation(item, trans->transid); btrfs_mark_buffer_dirty(path->nodes[0]); - *result = ins.objectid; btrfs_release_path(root, path); btrfs_free_path(path); return 0; } -static struct btrfs_csum_item *__lookup_csum_item(struct btrfs_root *root, - struct btrfs_path *path, - u64 objectid, u64 offset) +struct btrfs_csum_item *btrfs_lookup_csum(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + u64 objectid, u64 offset, + int cow) { int ret; struct btrfs_key file_key; @@ -61,19 +62,23 @@ static struct btrfs_csum_item *__lookup_csum_item(struct btrfs_root *root, file_key.offset = offset; file_key.flags = 0; btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY); - ret = btrfs_search_slot(NULL, root, &file_key, path, 0, 0); +printk("__lookup for %Lu\n", offset); + ret = btrfs_search_slot(trans, root, &file_key, path, 0, cow); if (ret < 0) goto fail; leaf = btrfs_buffer_leaf(path->nodes[0]); if (ret > 0) { ret = 1; - if (path->slots[0] == 0) + if (path->slots[0] == 0) { +printk("fail1\n"); goto fail; + } path->slots[0]--; btrfs_disk_key_to_cpu(&found_key, &leaf->items[path->slots[0]].key); if (btrfs_key_type(&found_key) != BTRFS_CSUM_ITEM_KEY || found_key.objectid != objectid) { +printk("fail2 type %u %Lu %Lu\n", btrfs_key_type(&found_key), found_key.objectid, objectid); goto fail; } csum_offset = (offset - found_key.offset) >> @@ -81,6 +86,7 @@ static struct btrfs_csum_item *__lookup_csum_item(struct btrfs_root *root, if (csum_offset >= btrfs_item_size(leaf->items + path->slots[0]) / sizeof(struct btrfs_csum_item)) { +printk("fail3, csum offset %lu size %u\n", csum_offset, btrfs_item_size(leaf->items + path->slots[0]) / sizeof(struct btrfs_csum_item)); goto fail; } } @@ -89,7 +95,7 @@ static struct btrfs_csum_item *__lookup_csum_item(struct btrfs_root *root, return item; fail: if (ret > 0) - ret = -EIO; + ret = -ENOENT; return ERR_PTR(ret); } @@ -105,7 +111,7 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans, int cow = mod != 0; struct btrfs_csum_item *csum_item; - csum_item = __lookup_csum_item(root, path, objectid, offset); + csum_item = btrfs_lookup_csum(trans, root, path, objectid, offset, 0); if (IS_ERR(csum_item)) return PTR_ERR(csum_item); file_key.objectid = objectid; @@ -113,7 +119,9 @@ int btrfs_lookup_file_extent(struct btrfs_trans_handle *trans, file_key.flags = 0; btrfs_set_key_type(&file_key, BTRFS_EXTENT_DATA_KEY); btrfs_release_path(root, path); +printk("lookup file extent searches for %Lu\n", file_key.offset); ret = btrfs_search_slot(trans, root, &file_key, path, ins_len, cow); +printk("ret is %d\n", ret); return ret; } @@ -134,17 +142,23 @@ int btrfs_csum_file_block(struct btrfs_trans_handle *trans, path = btrfs_alloc_path(); BUG_ON(!path); btrfs_init_path(path); + + item = btrfs_lookup_csum(trans, root, path, objectid, offset, 0); + if (!IS_ERR(item)) + goto found; + btrfs_release_path(root, path); file_key.objectid = objectid; file_key.offset = offset; file_key.flags = 0; btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY); +printk("searching for csum %Lu %Lu\n", objectid, offset); ret = btrfs_search_slot(trans, root, &file_key, path, sizeof(struct btrfs_csum_item), 1); +printk("ret %d\n", ret); if (ret < 0) goto fail; if (ret == 0) { - csum_offset = 0; - goto csum; + BUG(); } if (path->slots[0] == 0) { btrfs_release_path(root, path); @@ -153,12 +167,15 @@ int btrfs_csum_file_block(struct btrfs_trans_handle *trans, path->slots[0]--; leaf = btrfs_buffer_leaf(path->nodes[0]); btrfs_disk_key_to_cpu(&found_key, &leaf->items[path->slots[0]].key); +printk("found key %Lu %Lu %u\n", found_key.objectid, found_key.offset, found_key.flags); csum_offset = (offset - found_key.offset) >> root->fs_info->sb->s_blocksize_bits; +printk("csum_offset %Lu\n", csum_offset); if (btrfs_key_type(&found_key) != BTRFS_CSUM_ITEM_KEY || found_key.objectid != objectid || csum_offset >= MAX_CSUM_ITEMS(root)) { btrfs_release_path(root, path); +printk("insert1\n"); goto insert; } if (csum_offset >= btrfs_item_size(leaf->items + path->slots[0]) / @@ -166,11 +183,13 @@ int btrfs_csum_file_block(struct btrfs_trans_handle *trans, ret = btrfs_extend_item(trans, root, path, sizeof(struct btrfs_csum_item)); BUG_ON(ret); +printk("item extended\n"); goto csum; } insert: csum_offset = 0; +printk("inserting item %Lu %Lu %u\n", file_key.objectid, file_key.offset, file_key.flags); ret = btrfs_insert_empty_item(trans, root, path, &file_key, sizeof(struct btrfs_csum_item)); if (ret != 0 && ret != -EEXIST) @@ -180,12 +199,14 @@ csum: struct btrfs_csum_item); ret = 0; item += csum_offset; +found: ret = btrfs_csum_data(root, data, len, item->csum); btrfs_set_csum_extent_offset(item, extent_offset); btrfs_mark_buffer_dirty(path->nodes[0]); fail: btrfs_release_path(root, path); btrfs_free_path(path); +printk("return ret %d\n", ret); return ret; } @@ -208,7 +229,7 @@ int btrfs_csum_verify_file_block(struct btrfs_root *root, btrfs_set_key_type(&file_key, BTRFS_CSUM_ITEM_KEY); mutex_lock(&root->fs_info->fs_mutex); - item = __lookup_csum_item(root, path, objectid, offset); + item = btrfs_lookup_csum(NULL, root, path, objectid, offset, 0); if (IS_ERR(item)) { ret = PTR_ERR(item); goto fail; diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index ec689992fdf4..6a56416147e6 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1089,7 +1089,6 @@ static int btrfs_get_block_lock(struct inode *inode, sector_t iblock, extent_start = btrfs_disk_key_offset(&leaf->items[path->slots[0]].key); extent_start = extent_start >> inode->i_blkbits; - extent_start += btrfs_file_extent_offset(item); extent_end = extent_start + btrfs_file_extent_num_blocks(item); if (iblock >= extent_start && iblock < extent_end) { err = 0; @@ -1103,6 +1102,7 @@ allocate: err = 0; goto out; } +#if 0 ret = btrfs_alloc_file_extent(trans, root, objectid, iblock << inode->i_blkbits, 1, extent_end, &blocknr); @@ -1115,9 +1115,11 @@ allocate: map_bh(result, inode->i_sb, blocknr); btrfs_map_bh_to_logical(root, result, blocknr); +#endif out: btrfs_release_path(root, path); btrfs_free_path(path); +printk("mapping iblock %lu to %lu\n", iblock, result->b_blocknr); if (trans) btrfs_end_transaction(trans, root); return err; @@ -1273,8 +1275,244 @@ failed: return err; } -static int prepare_pages(struct btrfs_trans_handle *trans, - struct btrfs_root *root, +static int drop_csums(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct inode *inode, + u64 start, u64 end) +{ + struct btrfs_path *path; + struct btrfs_leaf *leaf; + struct btrfs_key key; + int slot; + struct btrfs_csum_item *item; + char *old_block = NULL; + u64 cur = start; + u64 found_end; + u64 num_csums; + u64 item_size; + int ret; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + while(cur < end) { + item = btrfs_lookup_csum(trans, root, path, + inode->i_ino, cur, 1); + if (IS_ERR(item)) { + cur += root->blocksize; + continue; + } + leaf = btrfs_buffer_leaf(path->nodes[0]); + slot = path->slots[0]; + btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key); + item_size = btrfs_item_size(leaf->items + slot); + num_csums = item_size / sizeof(struct btrfs_csum_item); + found_end = key.offset + (num_csums << inode->i_blkbits); + cur = found_end; + + if (found_end > end) { + char *src; + old_block = kmalloc(root->blocksize, GFP_NOFS); + src = btrfs_item_ptr(leaf, slot, char); + memcpy(old_block, src, item_size); + } + if (key.offset < start) { + u64 new_size = (start - key.offset) >> + inode->i_blkbits; + new_size *= sizeof(struct btrfs_csum_item); + ret = btrfs_truncate_item(trans, root, path, new_size); + BUG_ON(ret); + } else { + btrfs_del_item(trans, root, path); + } + btrfs_release_path(root, path); + if (found_end > end) { + char *dst; + int i; + int new_size; + + num_csums = (found_end - end) >> inode->i_blkbits; + new_size = num_csums * sizeof(struct btrfs_csum_item); + key.offset = end; + ret = btrfs_insert_empty_item(trans, root, path, + &key, new_size); + BUG_ON(ret); + dst = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), + path->slots[0], char); + memcpy(dst, old_block + item_size - new_size, + new_size); + item = (struct btrfs_csum_item *)dst; + for (i = 0; i < num_csums; i++) { + btrfs_set_csum_extent_offset(item, end); + item++; + } + mark_buffer_dirty(path->nodes[0]); + kfree(old_block); + break; + } + } + btrfs_free_path(path); + return 0; +} + +static int drop_extents(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct inode *inode, + u64 start, u64 end) +{ + int ret; + struct btrfs_key key; + struct btrfs_leaf *leaf; + int slot; + struct btrfs_file_extent_item *extent; + u64 extent_end; + int keep; + struct btrfs_file_extent_item old; + struct btrfs_path *path; + u64 search_start = start; + int bookend; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; +search_again: +printk("drop extent inode %lu start %Lu end %Lu\n", inode->i_ino, start, end); + ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino, + search_start, -1); + if (ret != 0) { +printk("lookup failed\n"); + goto out; + } + while(1) { + keep = 0; + bookend = 0; + leaf = btrfs_buffer_leaf(path->nodes[0]); + slot = path->slots[0]; + btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key); + +printk("found key %Lu %Lu %u\n", key.objectid, key.offset, key.flags); + + extent = btrfs_item_ptr(leaf, slot, + struct btrfs_file_extent_item); + extent_end = key.offset + + (btrfs_file_extent_num_blocks(extent) << + inode->i_blkbits); +printk("extent end is %Lu\n", extent_end); + if (key.offset >= end || key.objectid != inode->i_ino) { + ret = 0; + goto out; + } + if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) + goto next_leaf; + + if (end < extent_end && end >= key.offset) { + memcpy(&old, extent, sizeof(old)); + ret = btrfs_inc_extent_ref(trans, root, + btrfs_file_extent_disk_blocknr(&old), + btrfs_file_extent_disk_num_blocks(&old)); + BUG_ON(ret); + bookend = 1; + } + + if (start > key.offset) { + u64 new_num; + /* truncate existing extent */ + keep = 1; + WARN_ON(start & (root->blocksize - 1)); + new_num = (start - key.offset) >> inode->i_blkbits; +printk("truncating existing extent, was %Lu ", btrfs_file_extent_num_blocks(extent)); + btrfs_set_file_extent_num_blocks(extent, new_num); +printk("now %Lu\n", btrfs_file_extent_num_blocks(extent)); + + mark_buffer_dirty(path->nodes[0]); + } + if (!keep) { + u64 disk_blocknr; + u64 disk_num_blocks; +printk("del old\n"); + disk_blocknr = btrfs_file_extent_disk_blocknr(extent); + disk_num_blocks = + btrfs_file_extent_disk_num_blocks(extent); + search_start = key.offset + + (btrfs_file_extent_num_blocks(extent) << + inode->i_blkbits); + ret = btrfs_del_item(trans, root, path); + BUG_ON(ret); + btrfs_release_path(root, path); + + ret = btrfs_free_extent(trans, root, disk_blocknr, + disk_num_blocks, 0); + + BUG_ON(ret); + if (!bookend && search_start >= end) { + ret = 0; + goto out; + } + if (!bookend) + goto search_again; + } + if (bookend) { + /* create bookend */ + struct btrfs_key ins; +printk("bookend! extent end %Lu\n", extent_end); + ins.objectid = inode->i_ino; + ins.offset = end; + ins.flags = 0; + btrfs_set_key_type(&ins, BTRFS_EXTENT_DATA_KEY); + + btrfs_release_path(root, path); + ret = drop_csums(trans, root, inode, start, end); + BUG_ON(ret); + ret = btrfs_insert_empty_item(trans, root, path, &ins, + sizeof(*extent)); + BUG_ON(ret); + extent = btrfs_item_ptr( + btrfs_buffer_leaf(path->nodes[0]), + path->slots[0], + struct btrfs_file_extent_item); + btrfs_set_file_extent_disk_blocknr(extent, + btrfs_file_extent_disk_blocknr(&old)); + btrfs_set_file_extent_disk_num_blocks(extent, + btrfs_file_extent_disk_num_blocks(&old)); + + btrfs_set_file_extent_offset(extent, + btrfs_file_extent_offset(&old) + + ((end - key.offset) >> inode->i_blkbits)); + WARN_ON(btrfs_file_extent_num_blocks(&old) < + (end - key.offset) >> inode->i_blkbits); + btrfs_set_file_extent_num_blocks(extent, + btrfs_file_extent_num_blocks(&old) - + ((end - key.offset) >> inode->i_blkbits)); + + btrfs_set_file_extent_generation(extent, + btrfs_file_extent_generation(&old)); +printk("new bookend at offset %Lu, file_extent_offset %Lu, file_extent_num_blocks %Lu\n", end, btrfs_file_extent_offset(extent), btrfs_file_extent_num_blocks(extent)); + btrfs_mark_buffer_dirty(path->nodes[0]); + ret = 0; + goto out_nocsum; + } +next_leaf: + if (slot >= btrfs_header_nritems(&leaf->header) - 1) { + ret = btrfs_next_leaf(root, path); + if (ret) { + ret = 0; + goto out; + } + } else { + path->slots[0]++; + } + } + +out: + ret = drop_csums(trans, root, inode, start, end); + BUG_ON(ret); + +out_nocsum: + btrfs_free_path(path); + return ret; +} + +static int prepare_pages(struct btrfs_root *root, struct file *file, struct page **pages, size_t num_pages, @@ -1289,7 +1527,6 @@ static int prepare_pages(struct btrfs_trans_handle *trans, struct inode *inode = file->f_path.dentry->d_inode; int offset; int err = 0; - int ret; int this_write; struct buffer_head *bh; struct buffer_head *head; @@ -1305,18 +1542,21 @@ static int prepare_pages(struct btrfs_trans_handle *trans, } offset = pos & (PAGE_CACHE_SIZE -1); this_write = min(PAGE_CACHE_SIZE - offset, write_bytes); - if (!PageUptodate(pages[i]) && - (pages[i]->index == first_index || - pages[i]->index == last_index) && pos < isize) { +#if 0 + if ((pages[i]->index == first_index || + pages[i]->index == last_index) && pos < isize && + !PageUptodate(pages[i])) { ret = mpage_readpage(pages[i], btrfs_get_block); BUG_ON(ret); lock_page(pages[i]); } +#endif create_empty_buffers(pages[i], root->fs_info->sb->s_blocksize, (1 << BH_Uptodate)); head = page_buffers(pages[i]); bh = head; do { +printk("mapping page %lu to block %Lu\n", pages[i]->index, alloc_extent_start); err = btrfs_map_bh_to_logical(root, bh, alloc_extent_start); BUG_ON(err); @@ -1351,7 +1591,7 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf, int ret = 0; struct inode *inode = file->f_path.dentry->d_inode; struct btrfs_root *root = BTRFS_I(inode)->root; - struct page *pages[1]; + struct page *pages[8]; unsigned long first_index; unsigned long last_index; u64 start_pos; @@ -1359,6 +1599,7 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf, u64 alloc_extent_start; u64 orig_extent_start; struct btrfs_trans_handle *trans; + struct btrfs_key ins; if (file->f_flags & O_DIRECT) return -EINVAL; @@ -1390,16 +1631,24 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf, trans = btrfs_start_transaction(root, 1); if (!trans) { err = -ENOMEM; + mutex_unlock(&root->fs_info->fs_mutex); goto out_unlock; } - ret = btrfs_alloc_file_extent(trans, root, inode->i_ino, - start_pos, num_blocks, 1, - &alloc_extent_start); - BUG_ON(ret); - + if (start_pos < inode->i_size) { + ret = drop_extents(trans, root, inode, + start_pos, + (pos + count + root->blocksize -1) & + ~(root->blocksize - 1)); + } orig_extent_start = start_pos; - ret = btrfs_end_transaction(trans, root); + ret = btrfs_alloc_extent(trans, root, num_blocks, 1, + (u64)-1, &ins); + BUG_ON(ret); + ret = btrfs_insert_file_extent(trans, root, inode->i_ino, + start_pos, ins.objectid, ins.offset); BUG_ON(ret); + alloc_extent_start = ins.objectid; + ret = btrfs_end_transaction(trans, root); mutex_unlock(&root->fs_info->fs_mutex); while(count > 0) { @@ -1407,16 +1656,21 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf, size_t write_bytes = min(count, PAGE_CACHE_SIZE - offset); size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; - ret = prepare_pages(NULL, root, file, pages, num_pages, +printk("num_pages is %lu\n", num_pages); + + memset(pages, 0, sizeof(pages)); + ret = prepare_pages(root, file, pages, num_pages, pos, first_index, last_index, write_bytes, alloc_extent_start); BUG_ON(ret); + /* FIXME blocks != pagesize */ alloc_extent_start += num_pages; ret = btrfs_copy_from_user(pos, num_pages, write_bytes, pages, buf); BUG_ON(ret); +printk("2num_pages is %lu\n", num_pages); ret = dirty_and_release_pages(NULL, root, file, pages, num_pages, orig_extent_start, pos, write_bytes); -- 2.34.1