From bab39bf998133510f2dad08158006197ec0dabea Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Thu, 30 Jun 2011 14:42:28 -0400 Subject: Btrfs: use a worker thread to do caching A user reported a deadlock when copying a bunch of files. This is because they were low on memory and kthreadd got hung up trying to migrate pages for an allocation when starting the caching kthread. The page was locked by the person starting the caching kthread. To fix this we just need to use the async thread stuff so that the threads are already created and we don't have to worry about deadlocks. Thanks, Reported-by: Roman Mamedov Signed-off-by: Josef Bacik --- fs/btrfs/disk-io.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'fs/btrfs/disk-io.c') diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 1ac8db5dc0a..234a08404fc 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1807,6 +1807,9 @@ struct btrfs_root *open_ctree(struct super_block *sb, fs_info->thread_pool_size), &fs_info->generic_worker); + btrfs_init_workers(&fs_info->caching_workers, "cache", + 2, &fs_info->generic_worker); + /* a higher idle thresh on the submit workers makes it much more * likely that bios will be send down in a sane order to the * devices @@ -1860,6 +1863,7 @@ struct btrfs_root *open_ctree(struct super_block *sb, btrfs_start_workers(&fs_info->endio_write_workers, 1); btrfs_start_workers(&fs_info->endio_freespace_worker, 1); btrfs_start_workers(&fs_info->delayed_workers, 1); + btrfs_start_workers(&fs_info->caching_workers, 1); fs_info->bdi.ra_pages *= btrfs_super_num_devices(disk_super); fs_info->bdi.ra_pages = max(fs_info->bdi.ra_pages, @@ -2117,6 +2121,7 @@ fail_sb_buffer: btrfs_stop_workers(&fs_info->endio_freespace_worker); btrfs_stop_workers(&fs_info->submit_workers); btrfs_stop_workers(&fs_info->delayed_workers); + btrfs_stop_workers(&fs_info->caching_workers); fail_alloc: kfree(fs_info->delayed_root); fail_iput: @@ -2584,6 +2589,7 @@ int close_ctree(struct btrfs_root *root) btrfs_stop_workers(&fs_info->endio_freespace_worker); btrfs_stop_workers(&fs_info->submit_workers); btrfs_stop_workers(&fs_info->delayed_workers); + btrfs_stop_workers(&fs_info->caching_workers); btrfs_close_devices(fs_info->fs_devices); btrfs_mapping_tree_free(&fs_info->mapping_tree); -- cgit v1.2.3-70-g09d2 From a65917156e345946dbde3d7effd28124c6d6a8c2 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Tue, 19 Jul 2011 12:04:14 -0400 Subject: Btrfs: stop using highmem for extent_buffers The extent_buffers have a very complex interface where we use HIGHMEM for metadata and try to cache a kmap mapping to access the memory. The next commit adds reader/writer locks, and concurrent use of this kmap cache would make it even more complex. This commit drops the ability to use HIGHMEM with extent buffers, and rips out all of the related code. Signed-off-by: Chris Mason --- fs/btrfs/ctree.c | 189 +----------------------------------------------- fs/btrfs/disk-io.c | 7 +- fs/btrfs/extent_io.c | 67 ++++------------- fs/btrfs/extent_io.h | 11 +-- fs/btrfs/file-item.c | 32 +------- fs/btrfs/inode.c | 24 ------ fs/btrfs/struct-funcs.c | 100 ++++++++----------------- 7 files changed, 52 insertions(+), 378 deletions(-) (limited to 'fs/btrfs/disk-io.c') diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 2e667868e0d..d2431284b91 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -626,14 +626,6 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans, for (i = start_slot; i < end_slot; i++) { int close = 1; - if (!parent->map_token) { - map_extent_buffer(parent, - btrfs_node_key_ptr_offset(i), - sizeof(struct btrfs_key_ptr), - &parent->map_token, &parent->kaddr, - &parent->map_start, &parent->map_len, - KM_USER1); - } btrfs_node_key(parent, &disk_key, i); if (!progress_passed && comp_keys(&disk_key, progress) < 0) continue; @@ -656,11 +648,6 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans, last_block = blocknr; continue; } - if (parent->map_token) { - unmap_extent_buffer(parent, parent->map_token, - KM_USER1); - parent->map_token = NULL; - } cur = btrfs_find_tree_block(root, blocknr, blocksize); if (cur) @@ -701,11 +688,6 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans, btrfs_tree_unlock(cur); free_extent_buffer(cur); } - if (parent->map_token) { - unmap_extent_buffer(parent, parent->map_token, - KM_USER1); - parent->map_token = NULL; - } return err; } @@ -746,7 +728,6 @@ static noinline int generic_bin_search(struct extent_buffer *eb, struct btrfs_disk_key *tmp = NULL; struct btrfs_disk_key unaligned; unsigned long offset; - char *map_token = NULL; char *kaddr = NULL; unsigned long map_start = 0; unsigned long map_len = 0; @@ -756,18 +737,13 @@ static noinline int generic_bin_search(struct extent_buffer *eb, mid = (low + high) / 2; offset = p + mid * item_size; - if (!map_token || offset < map_start || + if (!kaddr || offset < map_start || (offset + sizeof(struct btrfs_disk_key)) > map_start + map_len) { - if (map_token) { - unmap_extent_buffer(eb, map_token, KM_USER0); - map_token = NULL; - } err = map_private_extent_buffer(eb, offset, sizeof(struct btrfs_disk_key), - &map_token, &kaddr, - &map_start, &map_len, KM_USER0); + &kaddr, &map_start, &map_len); if (!err) { tmp = (struct btrfs_disk_key *)(kaddr + offset - @@ -790,14 +766,10 @@ static noinline int generic_bin_search(struct extent_buffer *eb, high = mid; else { *slot = mid; - if (map_token) - unmap_extent_buffer(eb, map_token, KM_USER0); return 0; } } *slot = low; - if (map_token) - unmap_extent_buffer(eb, map_token, KM_USER0); return 1; } @@ -1228,7 +1200,6 @@ static void reada_for_search(struct btrfs_root *root, u32 nr; u32 blocksize; u32 nscan = 0; - bool map = true; if (level != 1) return; @@ -1250,19 +1221,8 @@ static void reada_for_search(struct btrfs_root *root, nritems = btrfs_header_nritems(node); nr = slot; - if (node->map_token || path->skip_locking) - map = false; while (1) { - if (map && !node->map_token) { - unsigned long offset = btrfs_node_key_ptr_offset(nr); - map_private_extent_buffer(node, offset, - sizeof(struct btrfs_key_ptr), - &node->map_token, - &node->kaddr, - &node->map_start, - &node->map_len, KM_USER1); - } if (direction < 0) { if (nr == 0) break; @@ -1281,11 +1241,6 @@ static void reada_for_search(struct btrfs_root *root, if ((search <= target && target - search <= 65536) || (search > target && search - target <= 65536)) { gen = btrfs_node_ptr_generation(node, nr); - if (map && node->map_token) { - unmap_extent_buffer(node, node->map_token, - KM_USER1); - node->map_token = NULL; - } readahead_tree_block(root, search, blocksize, gen); nread += blocksize; } @@ -1293,10 +1248,6 @@ static void reada_for_search(struct btrfs_root *root, if ((nread > 65536 || nscan > 32)) break; } - if (map && node->map_token) { - unmap_extent_buffer(node, node->map_token, KM_USER1); - node->map_token = NULL; - } } /* @@ -2253,14 +2204,6 @@ static noinline int __push_leaf_right(struct btrfs_trans_handle *trans, if (path->slots[0] == i) push_space += data_size; - if (!left->map_token) { - map_extent_buffer(left, (unsigned long)item, - sizeof(struct btrfs_item), - &left->map_token, &left->kaddr, - &left->map_start, &left->map_len, - KM_USER1); - } - this_item_size = btrfs_item_size(left, item); if (this_item_size + sizeof(*item) + push_space > free_space) break; @@ -2271,10 +2214,6 @@ static noinline int __push_leaf_right(struct btrfs_trans_handle *trans, break; i--; } - if (left->map_token) { - unmap_extent_buffer(left, left->map_token, KM_USER1); - left->map_token = NULL; - } if (push_items == 0) goto out_unlock; @@ -2316,21 +2255,10 @@ static noinline int __push_leaf_right(struct btrfs_trans_handle *trans, push_space = BTRFS_LEAF_DATA_SIZE(root); for (i = 0; i < right_nritems; i++) { item = btrfs_item_nr(right, i); - if (!right->map_token) { - map_extent_buffer(right, (unsigned long)item, - sizeof(struct btrfs_item), - &right->map_token, &right->kaddr, - &right->map_start, &right->map_len, - KM_USER1); - } push_space -= btrfs_item_size(right, item); btrfs_set_item_offset(right, item, push_space); } - if (right->map_token) { - unmap_extent_buffer(right, right->map_token, KM_USER1); - right->map_token = NULL; - } left_nritems -= push_items; btrfs_set_header_nritems(left, left_nritems); @@ -2467,13 +2395,6 @@ static noinline int __push_leaf_left(struct btrfs_trans_handle *trans, for (i = 0; i < nr; i++) { item = btrfs_item_nr(right, i); - if (!right->map_token) { - map_extent_buffer(right, (unsigned long)item, - sizeof(struct btrfs_item), - &right->map_token, &right->kaddr, - &right->map_start, &right->map_len, - KM_USER1); - } if (!empty && push_items > 0) { if (path->slots[0] < i) @@ -2496,11 +2417,6 @@ static noinline int __push_leaf_left(struct btrfs_trans_handle *trans, push_space += this_item_size + sizeof(*item); } - if (right->map_token) { - unmap_extent_buffer(right, right->map_token, KM_USER1); - right->map_token = NULL; - } - if (push_items == 0) { ret = 1; goto out; @@ -2530,23 +2446,12 @@ static noinline int __push_leaf_left(struct btrfs_trans_handle *trans, u32 ioff; item = btrfs_item_nr(left, i); - if (!left->map_token) { - map_extent_buffer(left, (unsigned long)item, - sizeof(struct btrfs_item), - &left->map_token, &left->kaddr, - &left->map_start, &left->map_len, - KM_USER1); - } ioff = btrfs_item_offset(left, item); btrfs_set_item_offset(left, item, ioff - (BTRFS_LEAF_DATA_SIZE(root) - old_left_item_size)); } btrfs_set_header_nritems(left, old_left_nritems + push_items); - if (left->map_token) { - unmap_extent_buffer(left, left->map_token, KM_USER1); - left->map_token = NULL; - } /* fixup right node */ if (push_items > right_nritems) { @@ -2574,21 +2479,9 @@ static noinline int __push_leaf_left(struct btrfs_trans_handle *trans, for (i = 0; i < right_nritems; i++) { item = btrfs_item_nr(right, i); - if (!right->map_token) { - map_extent_buffer(right, (unsigned long)item, - sizeof(struct btrfs_item), - &right->map_token, &right->kaddr, - &right->map_start, &right->map_len, - KM_USER1); - } - push_space = push_space - btrfs_item_size(right, item); btrfs_set_item_offset(right, item, push_space); } - if (right->map_token) { - unmap_extent_buffer(right, right->map_token, KM_USER1); - right->map_token = NULL; - } btrfs_mark_buffer_dirty(left); if (right_nritems) @@ -2729,23 +2622,10 @@ static noinline int copy_for_split(struct btrfs_trans_handle *trans, struct btrfs_item *item = btrfs_item_nr(right, i); u32 ioff; - if (!right->map_token) { - map_extent_buffer(right, (unsigned long)item, - sizeof(struct btrfs_item), - &right->map_token, &right->kaddr, - &right->map_start, &right->map_len, - KM_USER1); - } - ioff = btrfs_item_offset(right, item); btrfs_set_item_offset(right, item, ioff + rt_data_off); } - if (right->map_token) { - unmap_extent_buffer(right, right->map_token, KM_USER1); - right->map_token = NULL; - } - btrfs_set_header_nritems(l, mid); ret = 0; btrfs_item_key(right, &disk_key, 0); @@ -3264,23 +3144,10 @@ int btrfs_truncate_item(struct btrfs_trans_handle *trans, u32 ioff; item = btrfs_item_nr(leaf, i); - if (!leaf->map_token) { - map_extent_buffer(leaf, (unsigned long)item, - sizeof(struct btrfs_item), - &leaf->map_token, &leaf->kaddr, - &leaf->map_start, &leaf->map_len, - KM_USER1); - } - ioff = btrfs_item_offset(leaf, item); btrfs_set_item_offset(leaf, item, ioff + size_diff); } - if (leaf->map_token) { - unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); - leaf->map_token = NULL; - } - /* shift the data */ if (from_end) { memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + @@ -3377,22 +3244,10 @@ int btrfs_extend_item(struct btrfs_trans_handle *trans, u32 ioff; item = btrfs_item_nr(leaf, i); - if (!leaf->map_token) { - map_extent_buffer(leaf, (unsigned long)item, - sizeof(struct btrfs_item), - &leaf->map_token, &leaf->kaddr, - &leaf->map_start, &leaf->map_len, - KM_USER1); - } ioff = btrfs_item_offset(leaf, item); btrfs_set_item_offset(leaf, item, ioff - data_size); } - if (leaf->map_token) { - unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); - leaf->map_token = NULL; - } - /* shift the data */ memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) + data_end - data_size, btrfs_leaf_data(leaf) + @@ -3494,27 +3349,13 @@ int btrfs_insert_some_items(struct btrfs_trans_handle *trans, * item0..itemN ... dataN.offset..dataN.size .. data0.size */ /* first correct the data pointers */ - WARN_ON(leaf->map_token); for (i = slot; i < nritems; i++) { u32 ioff; item = btrfs_item_nr(leaf, i); - if (!leaf->map_token) { - map_extent_buffer(leaf, (unsigned long)item, - sizeof(struct btrfs_item), - &leaf->map_token, &leaf->kaddr, - &leaf->map_start, &leaf->map_len, - KM_USER1); - } - ioff = btrfs_item_offset(leaf, item); btrfs_set_item_offset(leaf, item, ioff - total_data); } - if (leaf->map_token) { - unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); - leaf->map_token = NULL; - } - /* shift the items */ memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + nr), btrfs_item_nr_offset(slot), @@ -3608,27 +3449,13 @@ int setup_items_for_insert(struct btrfs_trans_handle *trans, * item0..itemN ... dataN.offset..dataN.size .. data0.size */ /* first correct the data pointers */ - WARN_ON(leaf->map_token); for (i = slot; i < nritems; i++) { u32 ioff; item = btrfs_item_nr(leaf, i); - if (!leaf->map_token) { - map_extent_buffer(leaf, (unsigned long)item, - sizeof(struct btrfs_item), - &leaf->map_token, &leaf->kaddr, - &leaf->map_start, &leaf->map_len, - KM_USER1); - } - ioff = btrfs_item_offset(leaf, item); btrfs_set_item_offset(leaf, item, ioff - total_data); } - if (leaf->map_token) { - unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); - leaf->map_token = NULL; - } - /* shift the items */ memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + nr), btrfs_item_nr_offset(slot), @@ -3840,22 +3667,10 @@ int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root, u32 ioff; item = btrfs_item_nr(leaf, i); - if (!leaf->map_token) { - map_extent_buffer(leaf, (unsigned long)item, - sizeof(struct btrfs_item), - &leaf->map_token, &leaf->kaddr, - &leaf->map_start, &leaf->map_len, - KM_USER1); - } ioff = btrfs_item_offset(leaf, item); btrfs_set_item_offset(leaf, item, ioff + dsize); } - if (leaf->map_token) { - unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); - leaf->map_token = NULL; - } - memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot), btrfs_item_nr_offset(slot + nr), sizeof(struct btrfs_item) * diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 234a08404fc..97f22ff8326 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -217,7 +217,6 @@ static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf, unsigned long len; unsigned long cur_len; unsigned long offset = BTRFS_CSUM_SIZE; - char *map_token = NULL; char *kaddr; unsigned long map_start; unsigned long map_len; @@ -228,8 +227,7 @@ static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf, len = buf->len - offset; while (len > 0) { err = map_private_extent_buffer(buf, offset, 32, - &map_token, &kaddr, - &map_start, &map_len, KM_USER0); + &kaddr, &map_start, &map_len); if (err) return 1; cur_len = min(len, map_len - (offset - map_start)); @@ -237,7 +235,6 @@ static int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf, crc, cur_len); len -= cur_len; offset += cur_len; - unmap_extent_buffer(buf, map_token, KM_USER0); } if (csum_size > sizeof(inline_result)) { result = kzalloc(csum_size * sizeof(char), GFP_NOFS); @@ -1603,7 +1600,7 @@ struct btrfs_root *open_ctree(struct super_block *sb, goto fail_bdi; } - fs_info->btree_inode->i_mapping->flags &= ~__GFP_FS; + mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS); INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC); INIT_LIST_HEAD(&fs_info->trans_list); diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 89bbde46bd8..76ecbb8ed0e 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -3114,7 +3114,7 @@ struct extent_buffer *alloc_extent_buffer(struct extent_io_tree *tree, i = 0; } for (; i < num_pages; i++, index++) { - p = find_or_create_page(mapping, index, GFP_NOFS | __GFP_HIGHMEM); + p = find_or_create_page(mapping, index, GFP_NOFS); if (!p) { WARN_ON(1); goto free_eb; @@ -3487,9 +3487,8 @@ void read_extent_buffer(struct extent_buffer *eb, void *dstv, page = extent_buffer_page(eb, i); cur = min(len, (PAGE_CACHE_SIZE - offset)); - kaddr = kmap_atomic(page, KM_USER1); + kaddr = page_address(page); memcpy(dst, kaddr + offset, cur); - kunmap_atomic(kaddr, KM_USER1); dst += cur; len -= cur; @@ -3499,9 +3498,9 @@ void read_extent_buffer(struct extent_buffer *eb, void *dstv, } int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start, - unsigned long min_len, char **token, char **map, + unsigned long min_len, char **map, unsigned long *map_start, - unsigned long *map_len, int km) + unsigned long *map_len) { size_t offset = start & (PAGE_CACHE_SIZE - 1); char *kaddr; @@ -3531,42 +3530,12 @@ int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start, } p = extent_buffer_page(eb, i); - kaddr = kmap_atomic(p, km); - *token = kaddr; + kaddr = page_address(p); *map = kaddr + offset; *map_len = PAGE_CACHE_SIZE - offset; return 0; } -int map_extent_buffer(struct extent_buffer *eb, unsigned long start, - unsigned long min_len, - char **token, char **map, - unsigned long *map_start, - unsigned long *map_len, int km) -{ - int err; - int save = 0; - if (eb->map_token) { - unmap_extent_buffer(eb, eb->map_token, km); - eb->map_token = NULL; - save = 1; - } - err = map_private_extent_buffer(eb, start, min_len, token, map, - map_start, map_len, km); - if (!err && save) { - eb->map_token = *token; - eb->kaddr = *map; - eb->map_start = *map_start; - eb->map_len = *map_len; - } - return err; -} - -void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km) -{ - kunmap_atomic(token, km); -} - int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, unsigned long start, unsigned long len) @@ -3590,9 +3559,8 @@ int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, cur = min(len, (PAGE_CACHE_SIZE - offset)); - kaddr = kmap_atomic(page, KM_USER0); + kaddr = page_address(page); ret = memcmp(ptr, kaddr + offset, cur); - kunmap_atomic(kaddr, KM_USER0); if (ret) break; @@ -3625,9 +3593,8 @@ void write_extent_buffer(struct extent_buffer *eb, const void *srcv, WARN_ON(!PageUptodate(page)); cur = min(len, PAGE_CACHE_SIZE - offset); - kaddr = kmap_atomic(page, KM_USER1); + kaddr = page_address(page); memcpy(kaddr + offset, src, cur); - kunmap_atomic(kaddr, KM_USER1); src += cur; len -= cur; @@ -3656,9 +3623,8 @@ void memset_extent_buffer(struct extent_buffer *eb, char c, WARN_ON(!PageUptodate(page)); cur = min(len, PAGE_CACHE_SIZE - offset); - kaddr = kmap_atomic(page, KM_USER0); + kaddr = page_address(page); memset(kaddr + offset, c, cur); - kunmap_atomic(kaddr, KM_USER0); len -= cur; offset = 0; @@ -3689,9 +3655,8 @@ void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset)); - kaddr = kmap_atomic(page, KM_USER0); + kaddr = page_address(page); read_extent_buffer(src, kaddr + offset, src_offset, cur); - kunmap_atomic(kaddr, KM_USER0); src_offset += cur; len -= cur; @@ -3704,20 +3669,17 @@ static void move_pages(struct page *dst_page, struct page *src_page, unsigned long dst_off, unsigned long src_off, unsigned long len) { - char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); + char *dst_kaddr = page_address(dst_page); if (dst_page == src_page) { memmove(dst_kaddr + dst_off, dst_kaddr + src_off, len); } else { - char *src_kaddr = kmap_atomic(src_page, KM_USER1); + char *src_kaddr = page_address(src_page); char *p = dst_kaddr + dst_off + len; char *s = src_kaddr + src_off + len; while (len--) *--p = *--s; - - kunmap_atomic(src_kaddr, KM_USER1); } - kunmap_atomic(dst_kaddr, KM_USER0); } static inline bool areas_overlap(unsigned long src, unsigned long dst, unsigned long len) @@ -3730,20 +3692,17 @@ static void copy_pages(struct page *dst_page, struct page *src_page, unsigned long dst_off, unsigned long src_off, unsigned long len) { - char *dst_kaddr = kmap_atomic(dst_page, KM_USER0); + char *dst_kaddr = page_address(dst_page); char *src_kaddr; if (dst_page != src_page) { - src_kaddr = kmap_atomic(src_page, KM_USER1); + src_kaddr = page_address(src_page); } else { src_kaddr = dst_kaddr; BUG_ON(areas_overlap(src_off, dst_off, len)); } memcpy(dst_kaddr + dst_off, src_kaddr + src_off, len); - kunmap_atomic(dst_kaddr, KM_USER0); - if (dst_page != src_page) - kunmap_atomic(src_kaddr, KM_USER1); } void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h index a11a92ee2d3..b5f120cca91 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -120,8 +120,6 @@ struct extent_state { struct extent_buffer { u64 start; unsigned long len; - char *map_token; - char *kaddr; unsigned long map_start; unsigned long map_len; struct page *first_page; @@ -279,15 +277,10 @@ int clear_extent_buffer_uptodate(struct extent_io_tree *tree, int extent_buffer_uptodate(struct extent_io_tree *tree, struct extent_buffer *eb, struct extent_state *cached_state); -int map_extent_buffer(struct extent_buffer *eb, unsigned long offset, - unsigned long min_len, char **token, char **map, - unsigned long *map_start, - unsigned long *map_len, int km); int map_private_extent_buffer(struct extent_buffer *eb, unsigned long offset, - unsigned long min_len, char **token, char **map, + unsigned long min_len, char **map, unsigned long *map_start, - unsigned long *map_len, int km); -void unmap_extent_buffer(struct extent_buffer *eb, char *token, int km); + unsigned long *map_len); int extent_range_uptodate(struct extent_io_tree *tree, u64 start, u64 end); int extent_clear_unlock_delalloc(struct inode *inode, diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c index 90d4ee52cd4..bb22a4435b2 100644 --- a/fs/btrfs/file-item.c +++ b/fs/btrfs/file-item.c @@ -664,10 +664,6 @@ int btrfs_csum_file_blocks(struct btrfs_trans_handle *trans, struct btrfs_sector_sum *sector_sum; u32 nritems; u32 ins_size; - char *eb_map; - char *eb_token; - unsigned long map_len; - unsigned long map_start; u16 csum_size = btrfs_super_csum_size(&root->fs_info->super_copy); @@ -814,30 +810,9 @@ found: item_end = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_csum_item); item_end = (struct btrfs_csum_item *)((unsigned char *)item_end + btrfs_item_size_nr(leaf, path->slots[0])); - eb_token = NULL; next_sector: - if (!eb_token || - (unsigned long)item + csum_size >= map_start + map_len) { - int err; - - if (eb_token) - unmap_extent_buffer(leaf, eb_token, KM_USER1); - eb_token = NULL; - err = map_private_extent_buffer(leaf, (unsigned long)item, - csum_size, - &eb_token, &eb_map, - &map_start, &map_len, KM_USER1); - if (err) - eb_token = NULL; - } - if (eb_token) { - memcpy(eb_token + ((unsigned long)item & (PAGE_CACHE_SIZE - 1)), - §or_sum->sum, csum_size); - } else { - write_extent_buffer(leaf, §or_sum->sum, - (unsigned long)item, csum_size); - } + write_extent_buffer(leaf, §or_sum->sum, (unsigned long)item, csum_size); total_bytes += root->sectorsize; sector_sum++; @@ -850,10 +825,7 @@ next_sector: goto next_sector; } } - if (eb_token) { - unmap_extent_buffer(leaf, eb_token, KM_USER1); - eb_token = NULL; - } + btrfs_mark_buffer_dirty(path->nodes[0]); if (total_bytes < sums->len) { btrfs_release_path(path); diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 55d68ea1866..3b5763a2b7f 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -2541,13 +2541,6 @@ static void btrfs_read_locked_inode(struct inode *inode) inode_item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item); - if (!leaf->map_token) - map_private_extent_buffer(leaf, (unsigned long)inode_item, - sizeof(struct btrfs_inode_item), - &leaf->map_token, &leaf->kaddr, - &leaf->map_start, &leaf->map_len, - KM_USER1); - inode->i_mode = btrfs_inode_mode(leaf, inode_item); inode->i_nlink = btrfs_inode_nlink(leaf, inode_item); inode->i_uid = btrfs_inode_uid(leaf, inode_item); @@ -2585,11 +2578,6 @@ cache_acl: if (!maybe_acls) cache_no_acl(inode); - if (leaf->map_token) { - unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); - leaf->map_token = NULL; - } - btrfs_free_path(path); switch (inode->i_mode & S_IFMT) { @@ -2634,13 +2622,6 @@ static void fill_inode_item(struct btrfs_trans_handle *trans, struct btrfs_inode_item *item, struct inode *inode) { - if (!leaf->map_token) - map_private_extent_buffer(leaf, (unsigned long)item, - sizeof(struct btrfs_inode_item), - &leaf->map_token, &leaf->kaddr, - &leaf->map_start, &leaf->map_len, - KM_USER1); - btrfs_set_inode_uid(leaf, item, inode->i_uid); btrfs_set_inode_gid(leaf, item, inode->i_gid); btrfs_set_inode_size(leaf, item, BTRFS_I(inode)->disk_i_size); @@ -2669,11 +2650,6 @@ static void fill_inode_item(struct btrfs_trans_handle *trans, btrfs_set_inode_rdev(leaf, item, inode->i_rdev); btrfs_set_inode_flags(leaf, item, BTRFS_I(inode)->flags); btrfs_set_inode_block_group(leaf, item, 0); - - if (leaf->map_token) { - unmap_extent_buffer(leaf, leaf->map_token, KM_USER1); - leaf->map_token = NULL; - } } /* diff --git a/fs/btrfs/struct-funcs.c b/fs/btrfs/struct-funcs.c index c0f7ecaf1e7..bc1f6ad1844 100644 --- a/fs/btrfs/struct-funcs.c +++ b/fs/btrfs/struct-funcs.c @@ -50,36 +50,22 @@ u##bits btrfs_##name(struct extent_buffer *eb, \ unsigned long part_offset = (unsigned long)s; \ unsigned long offset = part_offset + offsetof(type, member); \ type *p; \ - /* ugly, but we want the fast path here */ \ - if (eb->map_token && offset >= eb->map_start && \ - offset + sizeof(((type *)0)->member) <= eb->map_start + \ - eb->map_len) { \ - p = (type *)(eb->kaddr + part_offset - eb->map_start); \ - return le##bits##_to_cpu(p->member); \ - } \ - { \ - int err; \ - char *map_token; \ - char *kaddr; \ - int unmap_on_exit = (eb->map_token == NULL); \ - unsigned long map_start; \ - unsigned long map_len; \ - u##bits res; \ - err = map_extent_buffer(eb, offset, \ - sizeof(((type *)0)->member), \ - &map_token, &kaddr, \ - &map_start, &map_len, KM_USER1); \ - if (err) { \ - __le##bits leres; \ - read_eb_member(eb, s, type, member, &leres); \ - return le##bits##_to_cpu(leres); \ - } \ - p = (type *)(kaddr + part_offset - map_start); \ - res = le##bits##_to_cpu(p->member); \ - if (unmap_on_exit) \ - unmap_extent_buffer(eb, map_token, KM_USER1); \ - return res; \ - } \ + int err; \ + char *kaddr; \ + unsigned long map_start; \ + unsigned long map_len; \ + u##bits res; \ + err = map_private_extent_buffer(eb, offset, \ + sizeof(((type *)0)->member), \ + &kaddr, &map_start, &map_len); \ + if (err) { \ + __le##bits leres; \ + read_eb_member(eb, s, type, member, &leres); \ + return le##bits##_to_cpu(leres); \ + } \ + p = (type *)(kaddr + part_offset - map_start); \ + res = le##bits##_to_cpu(p->member); \ + return res; \ } \ void btrfs_set_##name(struct extent_buffer *eb, \ type *s, u##bits val) \ @@ -87,36 +73,21 @@ void btrfs_set_##name(struct extent_buffer *eb, \ unsigned long part_offset = (unsigned long)s; \ unsigned long offset = part_offset + offsetof(type, member); \ type *p; \ - /* ugly, but we want the fast path here */ \ - if (eb->map_token && offset >= eb->map_start && \ - offset + sizeof(((type *)0)->member) <= eb->map_start + \ - eb->map_len) { \ - p = (type *)(eb->kaddr + part_offset - eb->map_start); \ - p->member = cpu_to_le##bits(val); \ - return; \ - } \ - { \ - int err; \ - char *map_token; \ - char *kaddr; \ - int unmap_on_exit = (eb->map_token == NULL); \ - unsigned long map_start; \ - unsigned long map_len; \ - err = map_extent_buffer(eb, offset, \ - sizeof(((type *)0)->member), \ - &map_token, &kaddr, \ - &map_start, &map_len, KM_USER1); \ - if (err) { \ - __le##bits val2; \ - val2 = cpu_to_le##bits(val); \ - write_eb_member(eb, s, type, member, &val2); \ - return; \ - } \ - p = (type *)(kaddr + part_offset - map_start); \ - p->member = cpu_to_le##bits(val); \ - if (unmap_on_exit) \ - unmap_extent_buffer(eb, map_token, KM_USER1); \ - } \ + int err; \ + char *kaddr; \ + unsigned long map_start; \ + unsigned long map_len; \ + err = map_private_extent_buffer(eb, offset, \ + sizeof(((type *)0)->member), \ + &kaddr, &map_start, &map_len); \ + if (err) { \ + __le##bits val2; \ + val2 = cpu_to_le##bits(val); \ + write_eb_member(eb, s, type, member, &val2); \ + return; \ + } \ + p = (type *)(kaddr + part_offset - map_start); \ + p->member = cpu_to_le##bits(val); \ } #include "ctree.h" @@ -125,15 +96,6 @@ void btrfs_node_key(struct extent_buffer *eb, struct btrfs_disk_key *disk_key, int nr) { unsigned long ptr = btrfs_node_key_ptr_offset(nr); - if (eb->map_token && ptr >= eb->map_start && - ptr + sizeof(*disk_key) <= eb->map_start + eb->map_len) { - memcpy(disk_key, eb->kaddr + ptr - eb->map_start, - sizeof(*disk_key)); - return; - } else if (eb->map_token) { - unmap_extent_buffer(eb, eb->map_token, KM_USER1); - eb->map_token = NULL; - } read_eb_member(eb, (struct btrfs_key_ptr *)ptr, struct btrfs_key_ptr, key, disk_key); } -- cgit v1.2.3-70-g09d2 From 85d4e461117b40eb10722f774566b19bd5e77879 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Tue, 26 Jul 2011 16:11:19 -0400 Subject: Btrfs: make a lockdep class for each root This patch was originally from Tejun Heo. lockdep complains about the btrfs locking because we sometimes take btree locks from two different trees at the same time. The current classes are based only on level in the btree, which isn't enough information for lockdep to figure out if the lock is safe. This patch makes a class for each type of tree, and lumps all the FS trees that actually have files and directories into the same class. Signed-off-by: Chris Mason --- fs/btrfs/disk-io.c | 103 +++++++++++++++++++++++++++++++++---------------- fs/btrfs/disk-io.h | 10 +++-- fs/btrfs/extent-tree.c | 2 +- fs/btrfs/volumes.c | 2 +- 4 files changed, 79 insertions(+), 38 deletions(-) (limited to 'fs/btrfs/disk-io.c') diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 97f22ff8326..94ecac33cf2 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -100,38 +100,83 @@ struct async_submit_bio { struct btrfs_work work; }; -/* These are used to set the lockdep class on the extent buffer locks. - * The class is set by the readpage_end_io_hook after the buffer has - * passed csum validation but before the pages are unlocked. +/* + * Lockdep class keys for extent_buffer->lock's in this root. For a given + * eb, the lockdep key is determined by the btrfs_root it belongs to and + * the level the eb occupies in the tree. + * + * Different roots are used for different purposes and may nest inside each + * other and they require separate keysets. As lockdep keys should be + * static, assign keysets according to the purpose of the root as indicated + * by btrfs_root->objectid. This ensures that all special purpose roots + * have separate keysets. * - * The lockdep class is also set by btrfs_init_new_buffer on freshly - * allocated blocks. + * Lock-nesting across peer nodes is always done with the immediate parent + * node locked thus preventing deadlock. As lockdep doesn't know this, use + * subclass to avoid triggering lockdep warning in such cases. * - * The class is based on the level in the tree block, which allows lockdep - * to know that lower nodes nest inside the locks of higher nodes. + * The key is set by the readpage_end_io_hook after the buffer has passed + * csum validation but before the pages are unlocked. It is also set by + * btrfs_init_new_buffer on freshly allocated blocks. * - * We also add a check to make sure the highest level of the tree is - * the same as our lockdep setup here. If BTRFS_MAX_LEVEL changes, this - * code needs update as well. + * We also add a check to make sure the highest level of the tree is the + * same as our lockdep setup here. If BTRFS_MAX_LEVEL changes, this code + * needs update as well. */ #ifdef CONFIG_DEBUG_LOCK_ALLOC # if BTRFS_MAX_LEVEL != 8 # error # endif -static struct lock_class_key btrfs_eb_class[BTRFS_MAX_LEVEL + 1]; -static const char *btrfs_eb_name[BTRFS_MAX_LEVEL + 1] = { - /* leaf */ - "btrfs-extent-00", - "btrfs-extent-01", - "btrfs-extent-02", - "btrfs-extent-03", - "btrfs-extent-04", - "btrfs-extent-05", - "btrfs-extent-06", - "btrfs-extent-07", - /* highest possible level */ - "btrfs-extent-08", + +static struct btrfs_lockdep_keyset { + u64 id; /* root objectid */ + const char *name_stem; /* lock name stem */ + char names[BTRFS_MAX_LEVEL + 1][20]; + struct lock_class_key keys[BTRFS_MAX_LEVEL + 1]; +} btrfs_lockdep_keysets[] = { + { .id = BTRFS_ROOT_TREE_OBJECTID, .name_stem = "root" }, + { .id = BTRFS_EXTENT_TREE_OBJECTID, .name_stem = "extent" }, + { .id = BTRFS_CHUNK_TREE_OBJECTID, .name_stem = "chunk" }, + { .id = BTRFS_DEV_TREE_OBJECTID, .name_stem = "dev" }, + { .id = BTRFS_FS_TREE_OBJECTID, .name_stem = "fs" }, + { .id = BTRFS_CSUM_TREE_OBJECTID, .name_stem = "csum" }, + { .id = BTRFS_ORPHAN_OBJECTID, .name_stem = "orphan" }, + { .id = BTRFS_TREE_LOG_OBJECTID, .name_stem = "log" }, + { .id = BTRFS_TREE_RELOC_OBJECTID, .name_stem = "treloc" }, + { .id = BTRFS_DATA_RELOC_TREE_OBJECTID, .name_stem = "dreloc" }, + { .id = 0, .name_stem = "tree" }, }; + +void __init btrfs_init_lockdep(void) +{ + int i, j; + + /* initialize lockdep class names */ + for (i = 0; i < ARRAY_SIZE(btrfs_lockdep_keysets); i++) { + struct btrfs_lockdep_keyset *ks = &btrfs_lockdep_keysets[i]; + + for (j = 0; j < ARRAY_SIZE(ks->names); j++) + snprintf(ks->names[j], sizeof(ks->names[j]), + "btrfs-%s-%02d", ks->name_stem, j); + } +} + +void btrfs_set_buffer_lockdep_class(u64 objectid, struct extent_buffer *eb, + int level) +{ + struct btrfs_lockdep_keyset *ks; + + BUG_ON(level >= ARRAY_SIZE(ks->keys)); + + /* find the matching keyset, id 0 is the default entry */ + for (ks = btrfs_lockdep_keysets; ks->id; ks++) + if (ks->id == objectid) + break; + + lockdep_set_class_and_name(&eb->lock, + &ks->keys[level], ks->names[level]); +} + #endif /* @@ -491,15 +536,6 @@ static noinline int check_leaf(struct btrfs_root *root, return 0; } -#ifdef CONFIG_DEBUG_LOCK_ALLOC -void btrfs_set_buffer_lockdep_class(struct extent_buffer *eb, int level) -{ - lockdep_set_class_and_name(&eb->lock, - &btrfs_eb_class[level], - btrfs_eb_name[level]); -} -#endif - static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end, struct extent_state *state) { @@ -550,7 +586,8 @@ static int btree_readpage_end_io_hook(struct page *page, u64 start, u64 end, } found_level = btrfs_header_level(eb); - btrfs_set_buffer_lockdep_class(eb, found_level); + btrfs_set_buffer_lockdep_class(btrfs_header_owner(eb), + eb, found_level); ret = csum_tree_block(root, eb, 1); if (ret) { diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h index a0b610a67aa..bec3ea4bd67 100644 --- a/fs/btrfs/disk-io.h +++ b/fs/btrfs/disk-io.h @@ -87,10 +87,14 @@ int btree_lock_page_hook(struct page *page); #ifdef CONFIG_DEBUG_LOCK_ALLOC -void btrfs_set_buffer_lockdep_class(struct extent_buffer *eb, int level); +void btrfs_init_lockdep(void); +void btrfs_set_buffer_lockdep_class(u64 objectid, + struct extent_buffer *eb, int level); #else -static inline void btrfs_set_buffer_lockdep_class(struct extent_buffer *eb, - int level) +static inline void btrfs_init_lockdep(void) +{ } +static inline void btrfs_set_buffer_lockdep_class(u64 objectid, + struct extent_buffer *eb, int level) { } #endif diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 2a782c2fcb6..06a5ee29b44 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -5625,7 +5625,7 @@ struct extent_buffer *btrfs_init_new_buffer(struct btrfs_trans_handle *trans, if (!buf) return ERR_PTR(-ENOMEM); btrfs_set_header_generation(buf, trans->transid); - btrfs_set_buffer_lockdep_class(buf, level); + btrfs_set_buffer_lockdep_class(root->root_key.objectid, buf, level); btrfs_tree_lock(buf); clean_tree_block(trans, root, buf); diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 19450bc5363..b89e372c754 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -3595,7 +3595,7 @@ int btrfs_read_sys_array(struct btrfs_root *root) if (!sb) return -ENOMEM; btrfs_set_buffer_uptodate(sb); - btrfs_set_buffer_lockdep_class(sb, 0); + btrfs_set_buffer_lockdep_class(root->root_key.objectid, sb, 0); write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE); array_size = btrfs_super_sys_array_size(super_copy); -- cgit v1.2.3-70-g09d2