From patchwork Wed May 21 09:41:14 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chandan Rajendra X-Patchwork-Id: 4215561 Return-Path: X-Original-To: patchwork-linux-btrfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 90A70BEEAB for ; Wed, 21 May 2014 09:41:56 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 84D8F201FB for ; Wed, 21 May 2014 09:41:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 320FF20148 for ; Wed, 21 May 2014 09:41:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752109AbaEUJlp (ORCPT ); Wed, 21 May 2014 05:41:45 -0400 Received: from e28smtp07.in.ibm.com ([122.248.162.7]:56901 "EHLO e28smtp07.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751033AbaEUJlf (ORCPT ); Wed, 21 May 2014 05:41:35 -0400 Received: from /spool/local by e28smtp07.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Date: Wed, 21 May 2014 15:11:14 +0530 Message-Id: <1400665278-4091-5-git-send-email-chandan@linux.vnet.ibm.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1400665278-4091-1-git-send-email-chandan@linux.vnet.ibm.com> References: <1400665278-4091-1-git-send-email-chandan@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14052109-8878-0000-0000-00000C8A81DF Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-7.5 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Chandra Seetharaman In order to handle multiple extent buffers per page, first we need to create a way to handle all the extent buffers that are attached to a page. This patch creates a new data structure 'struct extent_buffer_head', and moves fields that are common to all extent buffers in a page from 'struct extent buffer' to 'struct extent_buffer_head' Also, this patch moves EXTENT_BUFFER_TREE_REF, EXTENT_BUFFER_DUMMY and EXTENT_BUFFER_IN_TREE flags from extent_buffer->ebflags to extent_buffer_head->bflags. Signed-off-by: Chandra Seetharaman Signed-off-by: Chandan Rajendra --- fs/btrfs/backref.c | 2 +- fs/btrfs/ctree.c | 2 +- fs/btrfs/ctree.h | 6 +- fs/btrfs/disk-io.c | 46 ++++-- fs/btrfs/extent-tree.c | 6 +- fs/btrfs/extent_io.c | 372 +++++++++++++++++++++++++++++-------------- fs/btrfs/extent_io.h | 46 ++++-- fs/btrfs/volumes.c | 2 +- include/trace/events/btrfs.h | 2 +- 9 files changed, 326 insertions(+), 158 deletions(-) diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index a88da72..603ae44 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -1272,7 +1272,7 @@ char *btrfs_ref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path, eb = path->nodes[0]; /* make sure we can use eb after releasing the path */ if (eb != eb_in) { - atomic_inc(&eb->refs); + atomic_inc(&eb_head(eb)->refs); btrfs_tree_read_lock(eb); btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK); } diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index cbd3a7d..0d4ad91 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -169,7 +169,7 @@ struct extent_buffer *btrfs_root_node(struct btrfs_root *root) * the inc_not_zero dance and if it doesn't work then * synchronize_rcu and try again. */ - if (atomic_inc_not_zero(&eb->refs)) { + if (atomic_inc_not_zero(&eb_head(eb)->refs)) { rcu_read_unlock(); break; } diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index dac6653..901ada2 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -2138,14 +2138,16 @@ static inline void btrfs_set_token_##name(struct extent_buffer *eb, \ #define BTRFS_SETGET_HEADER_FUNCS(name, type, member, bits) \ static inline u##bits btrfs_##name(struct extent_buffer *eb) \ { \ - type *p = page_address(eb->pages[0]); \ + type *p = page_address(eb_head(eb)->pages[0]) + \ + (eb->start & (PAGE_CACHE_SIZE -1)); \ u##bits res = le##bits##_to_cpu(p->member); \ return res; \ } \ static inline void btrfs_set_##name(struct extent_buffer *eb, \ u##bits val) \ { \ - type *p = page_address(eb->pages[0]); \ + type *p = page_address(eb_head(eb)->pages[0]) + \ + (eb->start & (PAGE_CACHE_SIZE -1)); \ p->member = cpu_to_le##bits(val); \ } diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index cc1b423..bda2157 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1018,13 +1018,21 @@ static int btree_set_page_dirty(struct page *page) { #ifdef DEBUG struct extent_buffer *eb; + int i, dirty = 0; BUG_ON(!PagePrivate(page)); eb = (struct extent_buffer *)page->private; BUG_ON(!eb); - BUG_ON(!test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)); - BUG_ON(!atomic_read(&eb->refs)); - btrfs_assert_tree_locked(eb); + + do { + dirty = test_bit(EXTENT_BUFFER_DIRTY, &eb->ebflags); + if (dirty) + break; + } while ((eb = eb->eb_next) != NULL); + + BUG_ON(!dirty); + BUG_ON(!atomic_read(&(eb_head(eb)->refs))); + btrfs_assert_tree_locked(&ebh->eb); #endif return __set_page_dirty_nobuffers(page); } @@ -1068,7 +1076,7 @@ int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, u32 blocksize, if (!buf) return 0; - set_bit(EXTENT_BUFFER_READAHEAD, &buf->bflags); + set_bit(EXTENT_BUFFER_READAHEAD, &buf->ebflags); ret = read_extent_buffer_pages(io_tree, buf, 0, WAIT_PAGE_LOCK, btree_get_extent, mirror_num); @@ -1077,7 +1085,7 @@ int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, u32 blocksize, return ret; } - if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags)) { + if (test_bit(EXTENT_BUFFER_CORRUPT, &buf->ebflags)) { free_extent_buffer(buf); return -EIO; } else if (extent_buffer_uptodate(buf)) { @@ -1103,14 +1111,16 @@ struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root, int btrfs_write_tree_block(struct extent_buffer *buf) { - return filemap_fdatawrite_range(buf->pages[0]->mapping, buf->start, + return filemap_fdatawrite_range(eb_head(buf)->pages[0]->mapping, + buf->start, buf->start + buf->len - 1); } int btrfs_wait_tree_block_writeback(struct extent_buffer *buf) { - return filemap_fdatawait_range(buf->pages[0]->mapping, - buf->start, buf->start + buf->len - 1); + return filemap_fdatawait_range(eb_head(buf)->pages[0]->mapping, + buf->start, + buf->start + buf->len - 1); } struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr, @@ -1141,7 +1151,8 @@ void clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root, fs_info->running_transaction->transid) { btrfs_assert_tree_locked(buf); - if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)) { + if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, + &buf->ebflags)) { __percpu_counter_add(&fs_info->dirty_metadata_bytes, -buf->len, fs_info->dirty_metadata_batch); @@ -2613,7 +2624,8 @@ int open_ctree(struct super_block *sb, btrfs_super_chunk_root(disk_super), blocksize, generation); if (!chunk_root->node || - !test_bit(EXTENT_BUFFER_UPTODATE, &chunk_root->node->bflags)) { + !test_bit(EXTENT_BUFFER_UPTODATE, + &chunk_root->node->ebflags)) { printk(KERN_WARNING "BTRFS: failed to read chunk root on %s\n", sb->s_id); goto fail_tree_roots; @@ -2652,7 +2664,8 @@ retry_root_backup: btrfs_super_root(disk_super), blocksize, generation); if (!tree_root->node || - !test_bit(EXTENT_BUFFER_UPTODATE, &tree_root->node->bflags)) { + !test_bit(EXTENT_BUFFER_UPTODATE, + &tree_root->node->ebflags)) { printk(KERN_WARNING "BTRFS: failed to read tree root on %s\n", sb->s_id); @@ -3642,7 +3655,7 @@ int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid, int atomic) { int ret; - struct inode *btree_inode = buf->pages[0]->mapping->host; + struct inode *btree_inode = eb_head(buf)->pages[0]->mapping->host; ret = extent_buffer_uptodate(buf); if (!ret) @@ -3672,10 +3685,10 @@ void btrfs_mark_buffer_dirty(struct extent_buffer *buf) * enabled. Normal people shouldn't be marking dummy buffers as dirty * outside of the sanity tests. */ - if (unlikely(test_bit(EXTENT_BUFFER_DUMMY, &buf->bflags))) + if (unlikely(test_bit(EXTENT_BUFFER_DUMMY, &eb_head(buf)->bflags))) return; #endif - root = BTRFS_I(buf->pages[0]->mapping->host)->root; + root = BTRFS_I(eb_head(buf)->pages[0]->mapping->host)->root; btrfs_assert_tree_locked(buf); if (transid != root->fs_info->generation) WARN(1, KERN_CRIT "btrfs transid mismatch buffer %llu, " @@ -3724,7 +3737,8 @@ void btrfs_btree_balance_dirty_nodelay(struct btrfs_root *root) int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid) { - struct btrfs_root *root = BTRFS_I(buf->pages[0]->mapping->host)->root; + struct btrfs_root *root = + BTRFS_I(eb_head(buf)->pages[0]->mapping->host)->root; return btree_read_extent_buffer_pages(root, buf, 0, parent_transid); } @@ -3962,7 +3976,7 @@ static int btrfs_destroy_marked_extents(struct btrfs_root *root, wait_on_extent_buffer_writeback(eb); if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, - &eb->bflags)) + &eb->ebflags)) clear_extent_buffer_dirty(eb); free_extent_buffer_stale(eb); } diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 32312e0..232d0a3 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -5984,7 +5984,7 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans, goto out; } - WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags)); + WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->ebflags)); btrfs_add_free_space(cache, buf->start, buf->len); btrfs_update_reserved_bytes(cache, buf->len, RESERVE_FREE); @@ -6001,7 +6001,7 @@ out: * Deleting the buffer, clear the corrupt flag since it doesn't matter * anymore. */ - clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags); + clear_bit(EXTENT_BUFFER_CORRUPT, &buf->ebflags); btrfs_put_block_group(cache); } @@ -6887,7 +6887,7 @@ btrfs_init_new_buffer(struct btrfs_trans_handle *trans, struct btrfs_root *root, btrfs_set_buffer_lockdep_class(root->root_key.objectid, buf, level); btrfs_tree_lock(buf); clean_tree_block(trans, root, buf); - clear_bit(EXTENT_BUFFER_STALE, &buf->bflags); + clear_bit(EXTENT_BUFFER_STALE, &buf->ebflags); btrfs_set_lock_blocking(buf); btrfs_set_buffer_uptodate(buf); diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 17ff01b..5bc7b9b 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -56,6 +56,7 @@ void btrfs_leak_debug_check(void) { struct extent_state *state; struct extent_buffer *eb; + struct extent_buffer_head *ebh; while (!list_empty(&states)) { state = list_entry(states.next, struct extent_state, leak_list); @@ -68,12 +69,17 @@ void btrfs_leak_debug_check(void) } while (!list_empty(&buffers)) { - eb = list_entry(buffers.next, struct extent_buffer, leak_list); - printk(KERN_ERR "BTRFS: buffer leak start %llu len %lu " - "refs %d\n", - eb->start, eb->len, atomic_read(&eb->refs)); - list_del(&eb->leak_list); - kmem_cache_free(extent_buffer_cache, eb); + ebh = list_entry(buffers.next, struct extent_buffer_head, leak_list); + printk(KERN_ERR "btrfs buffer leak "); + + eb = &ebh->eb; + do { + printk(KERN_ERR "eb %p %llu:%lu ", eb, eb->start, eb->len); + } while ((eb = eb->eb_next) != NULL); + + printk(KERN_ERR "refs %d\n", atomic_read(&ebh->refs)); + list_del(&ebh->leak_list); + kmem_cache_free(extent_buffer_cache, ebh); } } @@ -144,7 +150,7 @@ int __init extent_io_init(void) return -ENOMEM; extent_buffer_cache = kmem_cache_create("btrfs_extent_buffer", - sizeof(struct extent_buffer), 0, + sizeof(struct extent_buffer_head), 0, SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); if (!extent_buffer_cache) goto free_state_cache; @@ -3484,7 +3490,7 @@ static int eb_wait(void *word) void wait_on_extent_buffer_writeback(struct extent_buffer *eb) { - wait_on_bit(&eb->bflags, EXTENT_BUFFER_WRITEBACK, eb_wait, + wait_on_bit(&eb->ebflags, EXTENT_BUFFER_WRITEBACK, eb_wait, TASK_UNINTERRUPTIBLE); } @@ -4410,29 +4416,47 @@ out: return ret; } -static void __free_extent_buffer(struct extent_buffer *eb) +static void __free_extent_buffer(struct extent_buffer_head *ebh) { - btrfs_leak_debug_del(&eb->leak_list); - kmem_cache_free(extent_buffer_cache, eb); + struct extent_buffer *eb, *next_eb; + + btrfs_leak_debug_del(&ebh->leak_list); + + eb = ebh->eb.eb_next; + while (eb) { + next_eb = eb->eb_next; + kfree(eb); + eb = next_eb; + } + + kmem_cache_free(extent_buffer_cache, ebh); } static int extent_buffer_under_io(struct extent_buffer *eb) { - return (atomic_read(&eb->io_pages) || - test_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags) || - test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)); + struct extent_buffer_head *ebh = eb->ebh; + int dirty_or_writeback = 0; + + for (eb = &ebh->eb; eb; eb = eb->eb_next) { + if (test_bit(EXTENT_BUFFER_WRITEBACK, &eb->ebflags) + || test_bit(EXTENT_BUFFER_DIRTY, &eb->ebflags)) + dirty_or_writeback = 1; + } + + return (atomic_read(&ebh->io_bvecs) || dirty_or_writeback); } /* * Helper for releasing extent buffer page. */ -static void btrfs_release_extent_buffer_page(struct extent_buffer *eb, +static noinline void btrfs_release_extent_buffer_page(struct extent_buffer *eb, unsigned long start_idx) { unsigned long index; unsigned long num_pages; struct page *page; - int mapped = !test_bit(EXTENT_BUFFER_DUMMY, &eb->bflags); + struct extent_buffer_head *ebh = eb_head(eb); + int mapped = !test_bit(EXTENT_BUFFER_DUMMY, &ebh->bflags); BUG_ON(extent_buffer_under_io(eb)); @@ -4442,6 +4466,8 @@ static void btrfs_release_extent_buffer_page(struct extent_buffer *eb, return; do { + struct extent_buffer *e; + index--; page = extent_buffer_page(eb, index); if (page && mapped) { @@ -4454,8 +4480,10 @@ static void btrfs_release_extent_buffer_page(struct extent_buffer *eb, * this eb. */ if (PagePrivate(page) && - page->private == (unsigned long)eb) { - BUG_ON(test_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)); + page->private == (unsigned long)(&ebh->eb)) { + for (e = &ebh->eb; !e; e = e->eb_next) + BUG_ON(test_bit(EXTENT_BUFFER_DIRTY, + &e->ebflags)); BUG_ON(PageDirty(page)); BUG_ON(PageWriteback(page)); /* @@ -4483,22 +4511,18 @@ static void btrfs_release_extent_buffer_page(struct extent_buffer *eb, static inline void btrfs_release_extent_buffer(struct extent_buffer *eb) { btrfs_release_extent_buffer_page(eb, 0); - __free_extent_buffer(eb); + __free_extent_buffer(eb_head(eb)); } -static struct extent_buffer * -__alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start, - unsigned long len, gfp_t mask) +static void __init_extent_buffer(struct extent_buffer *eb, + struct extent_buffer_head *ebh, + u64 start, + unsigned long len) { - struct extent_buffer *eb = NULL; - - eb = kmem_cache_zalloc(extent_buffer_cache, mask); - if (eb == NULL) - return NULL; eb->start = start; eb->len = len; - eb->fs_info = fs_info; - eb->bflags = 0; + eb->ebh = ebh; + eb->eb_next = NULL; rwlock_init(&eb->lock); atomic_set(&eb->write_locks, 0); atomic_set(&eb->read_locks, 0); @@ -4509,12 +4533,26 @@ __alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start, eb->lock_nested = 0; init_waitqueue_head(&eb->write_lock_wq); init_waitqueue_head(&eb->read_lock_wq); +} + +static struct extent_buffer *__alloc_extent_buffer(struct btrfs_fs_info *fs_info, + u64 start, unsigned long len, + gfp_t mask) +{ + struct extent_buffer_head *ebh = NULL; + struct extent_buffer *eb = NULL; + int i; - btrfs_leak_debug_add(&eb->leak_list, &buffers); + ebh = kmem_cache_zalloc(extent_buffer_cache, mask); + if (ebh == NULL) + return NULL; + ebh->fs_info = fs_info; + ebh->bflags = 0; + btrfs_leak_debug_add(&ebh->leak_list, &buffers); - spin_lock_init(&eb->refs_lock); - atomic_set(&eb->refs, 1); - atomic_set(&eb->io_pages, 0); + spin_lock_init(&ebh->refs_lock); + atomic_set(&ebh->refs, 1); + atomic_set(&ebh->io_bvecs, 0); /* * Sanity checks, currently the maximum is 64k covered by 16x 4k pages @@ -4523,6 +4561,29 @@ __alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start, > MAX_INLINE_EXTENT_BUFFER_SIZE); BUG_ON(len > MAX_INLINE_EXTENT_BUFFER_SIZE); + if (len < PAGE_CACHE_SIZE) { + struct extent_buffer *cur_eb, *prev_eb; + int ebs_per_page = PAGE_CACHE_SIZE / len; + u64 st = start & ~(PAGE_CACHE_SIZE - 1); + + prev_eb = NULL; + cur_eb = &ebh->eb; + for (i = 0; i < ebs_per_page; i++, st += len) { + if (prev_eb) { + cur_eb = kzalloc(sizeof(*eb), mask); + prev_eb->eb_next = cur_eb; + } + __init_extent_buffer(cur_eb, ebh, st, len); + prev_eb = cur_eb; + if (st == start) + eb = cur_eb; + } + BUG_ON(!eb); + } else { + eb = &ebh->eb; + __init_extent_buffer(eb, ebh, start, len); + } + return eb; } @@ -4543,15 +4604,16 @@ struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src) btrfs_release_extent_buffer(new); return NULL; } - attach_extent_buffer_page(new, p); + attach_extent_buffer_page(&(eb_head(new)->eb), p); WARN_ON(PageDirty(p)); SetPageUptodate(p); - new->pages[i] = p; + eb_head(new)->pages[i] = p; } + set_bit(EXTENT_BUFFER_UPTODATE, &new->ebflags); + set_bit(EXTENT_BUFFER_DUMMY, &eb_head(new)->bflags); + copy_extent_buffer(new, src, 0, 0, src->len); - set_bit(EXTENT_BUFFER_UPTODATE, &new->bflags); - set_bit(EXTENT_BUFFER_DUMMY, &new->bflags); return new; } @@ -4567,19 +4629,19 @@ struct extent_buffer *alloc_dummy_extent_buffer(u64 start, unsigned long len) return NULL; for (i = 0; i < num_pages; i++) { - eb->pages[i] = alloc_page(GFP_NOFS); - if (!eb->pages[i]) + eb_head(eb)->pages[i] = alloc_page(GFP_NOFS); + if (!eb_head(eb)->pages[i]) goto err; } set_extent_buffer_uptodate(eb); btrfs_set_header_nritems(eb, 0); - set_bit(EXTENT_BUFFER_DUMMY, &eb->bflags); + set_bit(EXTENT_BUFFER_DUMMY, &eb_head(eb)->bflags); return eb; err: for (; i > 0; i--) - __free_page(eb->pages[i - 1]); - __free_extent_buffer(eb); + __free_page(eb_head(eb)->pages[i - 1]); + __free_extent_buffer(eb_head(eb)); return NULL; } @@ -4606,14 +4668,15 @@ static void check_buffer_tree_ref(struct extent_buffer *eb) * So bump the ref count first, then set the bit. If someone * beat us to it, drop the ref we added. */ - refs = atomic_read(&eb->refs); - if (refs >= 2 && test_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags)) + refs = atomic_read(&eb_head(eb)->refs); + if (refs >= 2 && test_bit(EXTENT_BUFFER_TREE_REF, + &eb_head(eb)->bflags)) return; - spin_lock(&eb->refs_lock); - if (!test_and_set_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags)) - atomic_inc(&eb->refs); - spin_unlock(&eb->refs_lock); + spin_lock(&eb_head(eb)->refs_lock); + if (!test_and_set_bit(EXTENT_BUFFER_TREE_REF, &eb_head(eb)->bflags)) + atomic_inc(&eb_head(eb)->refs); + spin_unlock(&eb_head(eb)->refs_lock); } static void mark_extent_buffer_accessed(struct extent_buffer *eb) @@ -4632,15 +4695,24 @@ static void mark_extent_buffer_accessed(struct extent_buffer *eb) struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info, u64 start) { + struct extent_buffer_head *ebh; struct extent_buffer *eb; rcu_read_lock(); - eb = radix_tree_lookup(&fs_info->buffer_radix, - start >> PAGE_CACHE_SHIFT); - if (eb && atomic_inc_not_zero(&eb->refs)) { + ebh = radix_tree_lookup(&fs_info->buffer_radix, + start >> PAGE_CACHE_SHIFT); + if (ebh && atomic_inc_not_zero(&ebh->refs)) { rcu_read_unlock(); - mark_extent_buffer_accessed(eb); - return eb; + + eb = &ebh->eb; + do { + if (eb->start == start) { + mark_extent_buffer_accessed(eb); + return eb; + } + } while ((eb = eb->eb_next) != NULL); + + BUG(); } rcu_read_unlock(); @@ -4653,7 +4725,7 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info, unsigned long num_pages = num_extent_pages(start, len); unsigned long i; unsigned long index = start >> PAGE_CACHE_SHIFT; - struct extent_buffer *eb; + struct extent_buffer *eb, *cur_eb; struct extent_buffer *exists = NULL; struct page *p; struct address_space *mapping = fs_info->btree_inode->i_mapping; @@ -4683,12 +4755,18 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info, * overwrite page->private. */ exists = (struct extent_buffer *)p->private; - if (atomic_inc_not_zero(&exists->refs)) { + if (atomic_inc_not_zero(&eb_head(exists)->refs)) { spin_unlock(&mapping->private_lock); unlock_page(p); page_cache_release(p); - mark_extent_buffer_accessed(exists); - goto free_eb; + do { + if (exists->start == start) { + mark_extent_buffer_accessed(exists); + goto free_eb; + } + } while ((exists = exists->eb_next) != NULL); + + BUG(); } /* @@ -4699,11 +4777,11 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info, WARN_ON(PageDirty(p)); page_cache_release(p); } - attach_extent_buffer_page(eb, p); + attach_extent_buffer_page(&(eb_head(eb)->eb), p); spin_unlock(&mapping->private_lock); WARN_ON(PageDirty(p)); mark_page_accessed(p); - eb->pages[i] = p; + eb_head(eb)->pages[i] = p; if (!PageUptodate(p)) uptodate = 0; @@ -4712,16 +4790,22 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info, * and why we unlock later */ } - if (uptodate) - set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); + if (uptodate) { + cur_eb = &(eb_head(eb)->eb); + do { + set_bit(EXTENT_BUFFER_UPTODATE, &cur_eb->ebflags); + } while ((cur_eb = cur_eb->eb_next) != NULL); + } again: ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM); - if (ret) + if (ret) { + exists = NULL; goto free_eb; + } spin_lock(&fs_info->buffer_lock); ret = radix_tree_insert(&fs_info->buffer_radix, - start >> PAGE_CACHE_SHIFT, eb); + start >> PAGE_CACHE_SHIFT, eb_head(eb)); spin_unlock(&fs_info->buffer_lock); radix_tree_preload_end(); if (ret == -EEXIST) { @@ -4733,7 +4817,7 @@ again: } /* add one reference for the tree */ check_buffer_tree_ref(eb); - set_bit(EXTENT_BUFFER_IN_TREE, &eb->bflags); + set_bit(EXTENT_BUFFER_IN_TREE, &eb_head(eb)->bflags); /* * there is a race where release page may have @@ -4744,108 +4828,125 @@ again: * after the extent buffer is in the radix tree so * it doesn't get lost */ - SetPageChecked(eb->pages[0]); + SetPageChecked(eb_head(eb)->pages[0]); for (i = 1; i < num_pages; i++) { p = extent_buffer_page(eb, i); ClearPageChecked(p); unlock_page(p); } - unlock_page(eb->pages[0]); + unlock_page(eb_head(eb)->pages[0]); return eb; free_eb: for (i = 0; i < num_pages; i++) { - if (eb->pages[i]) - unlock_page(eb->pages[i]); + if (eb_head(eb)->pages[i]) + unlock_page(eb_head(eb)->pages[i]); } - WARN_ON(!atomic_dec_and_test(&eb->refs)); + WARN_ON(!atomic_dec_and_test(&eb_head(eb)->refs)); btrfs_release_extent_buffer(eb); return exists; } static inline void btrfs_release_extent_buffer_rcu(struct rcu_head *head) { - struct extent_buffer *eb = - container_of(head, struct extent_buffer, rcu_head); + struct extent_buffer_head *ebh = + container_of(head, struct extent_buffer_head, rcu_head); - __free_extent_buffer(eb); + __free_extent_buffer(ebh); } /* Expects to have eb->eb_lock already held */ -static int release_extent_buffer(struct extent_buffer *eb) +static int release_extent_buffer(struct extent_buffer_head *ebh) { - WARN_ON(atomic_read(&eb->refs) == 0); - if (atomic_dec_and_test(&eb->refs)) { - if (test_and_clear_bit(EXTENT_BUFFER_IN_TREE, &eb->bflags)) { - struct btrfs_fs_info *fs_info = eb->fs_info; + WARN_ON(atomic_read(&ebh->refs) == 0); + if (atomic_dec_and_test(&ebh->refs)) { + if (test_and_clear_bit(EXTENT_BUFFER_IN_TREE, &ebh->bflags)) { + struct btrfs_fs_info *fs_info = ebh->fs_info; - spin_unlock(&eb->refs_lock); + spin_unlock(&ebh->refs_lock); spin_lock(&fs_info->buffer_lock); radix_tree_delete(&fs_info->buffer_radix, - eb->start >> PAGE_CACHE_SHIFT); + ebh->eb.start >> PAGE_CACHE_SHIFT); spin_unlock(&fs_info->buffer_lock); } else { - spin_unlock(&eb->refs_lock); + spin_unlock(&ebh->refs_lock); } /* Should be safe to release our pages at this point */ - btrfs_release_extent_buffer_page(eb, 0); - call_rcu(&eb->rcu_head, btrfs_release_extent_buffer_rcu); + btrfs_release_extent_buffer_page(&ebh->eb, 0); + call_rcu(&ebh->rcu_head, btrfs_release_extent_buffer_rcu); return 1; } - spin_unlock(&eb->refs_lock); + spin_unlock(&ebh->refs_lock); return 0; } void free_extent_buffer(struct extent_buffer *eb) { + struct extent_buffer_head *ebh; int refs; int old; if (!eb) return; + ebh = eb_head(eb); while (1) { - refs = atomic_read(&eb->refs); + refs = atomic_read(&ebh->refs); if (refs <= 3) break; - old = atomic_cmpxchg(&eb->refs, refs, refs - 1); + old = atomic_cmpxchg(&ebh->refs, refs, refs - 1); if (old == refs) return; } - spin_lock(&eb->refs_lock); - if (atomic_read(&eb->refs) == 2 && - test_bit(EXTENT_BUFFER_DUMMY, &eb->bflags)) - atomic_dec(&eb->refs); + spin_lock(&ebh->refs_lock); + if (atomic_read(&ebh->refs) == 2 && + test_bit(EXTENT_BUFFER_DUMMY, &ebh->bflags)) + atomic_dec(&ebh->refs); - if (atomic_read(&eb->refs) == 2 && - test_bit(EXTENT_BUFFER_STALE, &eb->bflags) && + if (atomic_read(&ebh->refs) == 2 && + test_bit(EXTENT_BUFFER_STALE, &eb->ebflags) && !extent_buffer_under_io(eb) && - test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags)) - atomic_dec(&eb->refs); + test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &ebh->bflags)) + atomic_dec(&ebh->refs); /* * I know this is terrible, but it's temporary until we stop tracking * the uptodate bits and such for the extent buffers. */ - release_extent_buffer(eb); + release_extent_buffer(ebh); } void free_extent_buffer_stale(struct extent_buffer *eb) { + struct extent_buffer_head *ebh; if (!eb) return; - spin_lock(&eb->refs_lock); - set_bit(EXTENT_BUFFER_STALE, &eb->bflags); + ebh = eb_head(eb); + spin_lock(&ebh->refs_lock); + + set_bit(EXTENT_BUFFER_STALE, &eb->ebflags); + if (atomic_read(&ebh->refs) == 2 && !extent_buffer_under_io(eb) && + test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &ebh->bflags)) + atomic_dec(&ebh->refs); + + release_extent_buffer(ebh); +} + +static int page_ebs_clean(struct extent_buffer_head *ebh) +{ + struct extent_buffer *eb = &ebh->eb;; + + do { + if (test_bit(EXTENT_BUFFER_DIRTY, &eb->ebflags)) + return 0; + } while ((eb = eb->eb_next) != NULL); - if (atomic_read(&eb->refs) == 2 && !extent_buffer_under_io(eb) && - test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags)) - atomic_dec(&eb->refs); - release_extent_buffer(eb); + return 1; } void clear_extent_buffer_dirty(struct extent_buffer *eb) @@ -4856,6 +4957,9 @@ void clear_extent_buffer_dirty(struct extent_buffer *eb) num_pages = num_extent_pages(eb->start, eb->len); + if (eb->len < PAGE_CACHE_SIZE && !page_ebs_clean(eb_head(eb))) + return; + for (i = 0; i < num_pages; i++) { page = extent_buffer_page(eb, i); if (!PageDirty(page)) @@ -4875,7 +4979,7 @@ void clear_extent_buffer_dirty(struct extent_buffer *eb) ClearPageError(page); unlock_page(page); } - WARN_ON(atomic_read(&eb->refs) == 0); + WARN_ON(atomic_read(&eb_head(eb)->refs) == 0); } int set_extent_buffer_dirty(struct extent_buffer *eb) @@ -4886,11 +4990,11 @@ int set_extent_buffer_dirty(struct extent_buffer *eb) check_buffer_tree_ref(eb); - was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->bflags); + was_dirty = test_and_set_bit(EXTENT_BUFFER_DIRTY, &eb->ebflags); num_pages = num_extent_pages(eb->start, eb->len); - WARN_ON(atomic_read(&eb->refs) == 0); - WARN_ON(!test_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags)); + WARN_ON(atomic_read(&eb_head(eb)->refs) == 0); + WARN_ON(!test_bit(EXTENT_BUFFER_TREE_REF, &eb_head(eb)->bflags)); for (i = 0; i < num_pages; i++) set_page_dirty(extent_buffer_page(eb, i)); @@ -4903,7 +5007,9 @@ int clear_extent_buffer_uptodate(struct extent_buffer *eb) struct page *page; unsigned long num_pages; - clear_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); + if (!eb || !eb_head(eb)) + return 0; + clear_bit(EXTENT_BUFFER_UPTODATE, &eb->ebflags); num_pages = num_extent_pages(eb->start, eb->len); for (i = 0; i < num_pages; i++) { page = extent_buffer_page(eb, i); @@ -4915,22 +5021,43 @@ int clear_extent_buffer_uptodate(struct extent_buffer *eb) int set_extent_buffer_uptodate(struct extent_buffer *eb) { + struct extent_buffer_head *ebh; unsigned long i; struct page *page; unsigned long num_pages; + int uptodate; - set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); - num_pages = num_extent_pages(eb->start, eb->len); - for (i = 0; i < num_pages; i++) { - page = extent_buffer_page(eb, i); - SetPageUptodate(page); + ebh = eb->ebh; + + set_bit(EXTENT_BUFFER_UPTODATE, &eb->ebflags); + if (eb->len < PAGE_CACHE_SIZE) { + eb = &(eb_head(eb)->eb); + uptodate = 1; + do { + if (!test_bit(EXTENT_BUFFER_UPTODATE, &eb->ebflags)) { + uptodate = 0; + break; + } + } while ((eb = eb->eb_next) != NULL); + + if (uptodate) { + page = extent_buffer_page(&ebh->eb, 0); + SetPageUptodate(page); + } + } else { + num_pages = num_extent_pages(eb->start, eb->len); + for (i = 0; i < num_pages; i++) { + page = extent_buffer_page(eb, i); + SetPageUptodate(page); + } } + return 0; } int extent_buffer_uptodate(struct extent_buffer *eb) { - return test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); + return test_bit(EXTENT_BUFFER_UPTODATE, &eb->ebflags); } int read_extent_buffer_pages(struct extent_io_tree *tree, @@ -5150,9 +5277,10 @@ void write_extent_buffer(struct extent_buffer *eb, const void *srcv, offset = (start_offset + start) & (PAGE_CACHE_SIZE - 1); + WARN_ON(!test_bit(EXTENT_BUFFER_UPTODATE, &eb->ebflags)); + while (len > 0) { page = extent_buffer_page(eb, i); - WARN_ON(!PageUptodate(page)); cur = min(len, PAGE_CACHE_SIZE - offset); kaddr = page_address(page); @@ -5177,12 +5305,12 @@ void memset_extent_buffer(struct extent_buffer *eb, char c, WARN_ON(start > eb->len); WARN_ON(start + len > eb->start + eb->len); + WARN_ON(!test_bit(EXTENT_BUFFER_UPTODATE, &eb->ebflags)); offset = (start_offset + start) & (PAGE_CACHE_SIZE - 1); while (len > 0) { page = extent_buffer_page(eb, i); - WARN_ON(!PageUptodate(page)); cur = min(len, PAGE_CACHE_SIZE - offset); kaddr = page_address(page); @@ -5211,9 +5339,10 @@ void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, offset = (start_offset + dst_offset) & (PAGE_CACHE_SIZE - 1); + WARN_ON(!test_bit(EXTENT_BUFFER_UPTODATE, &dst->ebflags)); + while (len > 0) { page = extent_buffer_page(dst, i); - WARN_ON(!PageUptodate(page)); cur = min(len, (unsigned long)(PAGE_CACHE_SIZE - offset)); @@ -5350,6 +5479,7 @@ void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, int try_release_extent_buffer(struct page *page) { + struct extent_buffer_head *ebh; struct extent_buffer *eb; /* @@ -5365,14 +5495,15 @@ int try_release_extent_buffer(struct page *page) eb = (struct extent_buffer *)page->private; BUG_ON(!eb); + ebh = eb->ebh; /* * This is a little awful but should be ok, we need to make sure that * the eb doesn't disappear out from under us while we're looking at * this page. */ - spin_lock(&eb->refs_lock); - if (atomic_read(&eb->refs) != 1 || extent_buffer_under_io(eb)) { - spin_unlock(&eb->refs_lock); + spin_lock(&ebh->refs_lock); + if (atomic_read(&ebh->refs) != 1 || extent_buffer_under_io(eb)) { + spin_unlock(&ebh->refs_lock); spin_unlock(&page->mapping->private_lock); return 0; } @@ -5382,10 +5513,11 @@ int try_release_extent_buffer(struct page *page) * If tree ref isn't set then we know the ref on this eb is a real ref, * so just return, this page will likely be freed soon anyway. */ - if (!test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &eb->bflags)) { - spin_unlock(&eb->refs_lock); + if (!test_and_clear_bit(EXTENT_BUFFER_TREE_REF, &ebh->bflags)) { + spin_unlock(&ebh->refs_lock); return 0; } - return release_extent_buffer(eb); + return release_extent_buffer(ebh); } + diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h index 58b27e5..fa0d576 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -123,19 +123,17 @@ struct extent_state { #define INLINE_EXTENT_BUFFER_PAGES 16 #define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_CACHE_SIZE) + +/* Forward declaration */ +struct extent_buffer_head; + struct extent_buffer { u64 start; unsigned long len; - unsigned long map_start; - unsigned long map_len; - unsigned long bflags; - struct btrfs_fs_info *fs_info; - spinlock_t refs_lock; - atomic_t refs; - atomic_t io_pages; + unsigned long ebflags; + struct extent_buffer_head *ebh; + struct extent_buffer *eb_next; int read_mirror; - struct rcu_head rcu_head; - pid_t lock_owner; /* count of read lock holders on the extent buffer */ atomic_t write_locks; @@ -146,6 +144,8 @@ struct extent_buffer { atomic_t spinning_writers; int lock_nested; + pid_t lock_owner; + /* protects write locks */ rwlock_t lock; @@ -159,7 +159,19 @@ struct extent_buffer { */ wait_queue_head_t read_lock_wq; wait_queue_head_t lock_wq; +}; + +struct extent_buffer_head { + unsigned long bflags; + struct btrfs_fs_info *fs_info; + spinlock_t refs_lock; + atomic_t refs; + atomic_t io_bvecs; + struct rcu_head rcu_head; + struct page *pages[INLINE_EXTENT_BUFFER_PAGES]; + + struct extent_buffer eb; #ifdef CONFIG_BTRFS_DEBUG struct list_head leak_list; #endif @@ -176,6 +188,14 @@ static inline int extent_compress_type(unsigned long bio_flags) return bio_flags >> EXTENT_BIO_FLAG_SHIFT; } +/* + * return the extent_buffer_head that contains the extent buffer provided. + */ +static inline struct extent_buffer_head *eb_head(struct extent_buffer *eb) +{ + return eb->ebh; + +} struct extent_map_tree; typedef struct extent_map *(get_extent_t)(struct inode *inode, @@ -287,15 +307,15 @@ static inline unsigned long num_extent_pages(u64 start, u64 len) (start >> PAGE_CACHE_SHIFT); } -static inline struct page *extent_buffer_page(struct extent_buffer *eb, - unsigned long i) +static inline struct page *extent_buffer_page( + struct extent_buffer *eb, unsigned long i) { - return eb->pages[i]; + return eb_head(eb)->pages[i]; } static inline void extent_buffer_get(struct extent_buffer *eb) { - atomic_inc(&eb->refs); + atomic_inc(&eb_head(eb)->refs); } int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 07629e9..1ec359b 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -5936,7 +5936,7 @@ int btrfs_read_sys_array(struct btrfs_root *root) * to silence the warning eg. on PowerPC 64. */ if (PAGE_CACHE_SIZE > BTRFS_SUPER_INFO_SIZE) - SetPageUptodate(sb->pages[0]); + SetPageUptodate(eb_head(sb)->pages[0]); write_extent_buffer(sb, super_copy, 0, BTRFS_SUPER_INFO_SIZE); array_size = btrfs_super_sys_array_size(super_copy); diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h index 3176cdc..5b79ac2 100644 --- a/include/trace/events/btrfs.h +++ b/include/trace/events/btrfs.h @@ -695,7 +695,7 @@ TRACE_EVENT(btrfs_cow_block, TP_fast_assign( __entry->root_objectid = root->root_key.objectid; __entry->buf_start = buf->start; - __entry->refs = atomic_read(&buf->refs); + __entry->refs = atomic_read(&eb_head(buf)->refs); __entry->cow_start = cow->start; __entry->buf_level = btrfs_header_level(buf); __entry->cow_level = btrfs_header_level(cow);