From patchwork Sun Apr 17 12:24:51 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chandan Rajendra X-Patchwork-Id: 8862751 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 [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 8D521BF29F for ; Sun, 17 Apr 2016 12:25:20 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 30FCF20172 for ; Sun, 17 Apr 2016 12:25:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8AC3E20166 for ; Sun, 17 Apr 2016 12:25:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752796AbcDQMZG (ORCPT ); Sun, 17 Apr 2016 08:25:06 -0400 Received: from e28smtp09.in.ibm.com ([125.16.236.9]:58557 "EHLO e28smtp09.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751542AbcDQMZD (ORCPT ); Sun, 17 Apr 2016 08:25:03 -0400 Received: from localhost by e28smtp09.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Sun, 17 Apr 2016 17:54:57 +0530 X-IBM-Helo: d28relay08.in.ibm.com X-IBM-MailFrom: chandan@linux.vnet.ibm.com X-IBM-RcptTo: linux-btrfs@vger.kernel.org Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay08.in.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u3HCOuTx22085660 for ; Sun, 17 Apr 2016 17:54:57 +0530 Received: from d28av04.in.ibm.com (localhost [127.0.0.1]) by d28av04.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u3HCOtTs001544 for ; Sun, 17 Apr 2016 17:54:56 +0530 Received: from localhost.in.ibm.com ([9.77.205.82]) by d28av04.in.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id u3HCOr8l001475; Sun, 17 Apr 2016 17:54:53 +0530 From: Chandan Rajendra To: linux-btrfs@vger.kernel.org Cc: Chandan Rajendra , dsterba@suse.cz, clm@fb.com, jbacik@fb.com, aneesh.kumar@linux.vnet.ibm.com, chandan@mykolab.com Subject: [PATCH] Btrfs: subpage-blocksize: Define extent_buffer_head. Date: Sun, 17 Apr 2016 17:54:51 +0530 Message-Id: <1460895891-3566-1-git-send-email-chandan@linux.vnet.ibm.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1460641107-13834-5-git-send-email-chandan@linux.vnet.ibm.com> References: <1460641107-13834-5-git-send-email-chandan@linux.vnet.ibm.com> X-TM-AS-MML: disable x-cbid: 16041712-0041-0000-0000-00000C1615F6 Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Spam-Status: No, score=-7.9 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 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 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. Reviewed-by: Liu Bo Signed-off-by: Chandan Rajendra --- fs/btrfs/ctree.c | 2 +- fs/btrfs/ctree.h | 6 +- fs/btrfs/disk-io.c | 72 +++--- fs/btrfs/extent-tree.c | 6 +- fs/btrfs/extent_io.c | 588 ++++++++++++++++++++++++++++--------------- fs/btrfs/extent_io.h | 63 +++-- fs/btrfs/root-tree.c | 2 +- fs/btrfs/volumes.c | 2 +- include/trace/events/btrfs.h | 2 +- 9 files changed, 489 insertions(+), 254 deletions(-) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index ec7928a..23118f4 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -160,7 +160,7 @@ 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 84a6a5b..8e6eafa 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -2464,14 +2464,16 @@ 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_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_SIZE -1)); \ p->member = cpu_to_le##bits(val); \ } diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 4e47849..f0cf922 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -375,10 +375,9 @@ static int verify_parent_transid(struct extent_io_tree *io_tree, ret = 0; goto out; } - btrfs_err_rl(eb->fs_info, + btrfs_err_rl(eb_head(eb)->fs_info, "parent transid verify failed on %llu wanted %llu found %llu", - eb->start, - parent_transid, btrfs_header_generation(eb)); + eb->start, parent_transid, btrfs_header_generation(eb)); ret = 1; /* @@ -452,7 +451,7 @@ static int btree_read_extent_buffer_pages(struct btrfs_root *root, int mirror_num = 0; int failed_mirror = 0; - clear_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags); + clear_bit(EXTENT_BUFFER_CORRUPT, &eb->ebflags); io_tree = &BTRFS_I(root->fs_info->btree_inode)->io_tree; while (1) { ret = read_extent_buffer_pages(io_tree, eb, start, @@ -471,7 +470,7 @@ static int btree_read_extent_buffer_pages(struct btrfs_root *root, * there is no reason to read the other copies, they won't be * any less wrong. */ - if (test_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags)) + if (test_bit(EXTENT_BUFFER_CORRUPT, &eb->ebflags)) break; num_copies = btrfs_num_copies(root->fs_info, @@ -510,7 +509,7 @@ static int csum_dirty_buffer(struct btrfs_fs_info *fs_info, struct page *page) struct extent_buffer *eb; eb = (struct extent_buffer *)page->private; - if (page != eb->pages[0]) + if (page != eb_head(eb)->pages[0]) return 0; found_start = btrfs_header_bytenr(eb); @@ -635,12 +634,12 @@ static int btree_readpage_end_io_hook(struct btrfs_io_bio *io_bio, */ extent_buffer_get(eb); - reads_done = atomic_dec_and_test(&eb->io_pages); + reads_done = atomic_dec_and_test(&eb_head(eb)->io_bvecs); if (!reads_done) goto err; eb->read_mirror = mirror; - if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags)) { + if (test_bit(EXTENT_BUFFER_READ_ERR, &eb->ebflags)) { ret = -EIO; goto err; } @@ -679,7 +678,7 @@ static int btree_readpage_end_io_hook(struct btrfs_io_bio *io_bio, * return -EIO. */ if (found_level == 0 && check_leaf(root, eb)) { - set_bit(EXTENT_BUFFER_CORRUPT, &eb->bflags); + set_bit(EXTENT_BUFFER_CORRUPT, &eb->ebflags); ret = -EIO; } @@ -687,7 +686,7 @@ static int btree_readpage_end_io_hook(struct btrfs_io_bio *io_bio, set_extent_buffer_uptodate(eb); err: if (reads_done && - test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) + test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->ebflags)) btree_readahead_hook(fs_info, eb, eb->start, ret); if (ret) { @@ -696,7 +695,7 @@ err: * again, we have to make sure it has something * to decrement */ - atomic_inc(&eb->io_pages); + atomic_inc(&eb_head(eb)->io_bvecs); clear_extent_buffer_uptodate(eb); } free_extent_buffer(eb); @@ -709,11 +708,11 @@ static int btree_io_failed_hook(struct page *page, int failed_mirror) struct extent_buffer *eb; eb = (struct extent_buffer *)page->private; - set_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags); + set_bit(EXTENT_BUFFER_READ_ERR, &eb->ebflags); eb->read_mirror = failed_mirror; - atomic_dec(&eb->io_pages); - if (test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->bflags)) - btree_readahead_hook(eb->fs_info, eb, eb->start, -EIO); + atomic_dec(&eb_head(eb)->io_bvecs); + if (test_and_clear_bit(EXTENT_BUFFER_READAHEAD, &eb->ebflags)) + btree_readahead_hook(eb_head(eb)->fs_info, eb, eb->start, -EIO); return -EIO; /* we fixed nothing */ } @@ -1070,13 +1069,24 @@ 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); + + eb = (struct extent_buffer *)page->private; + BUG_ON(!atomic_read(&(eb_head(eb)->refs))); + + btrfs_assert_tree_locked(&ebh->eb); #endif return __set_page_dirty_nobuffers(page); } @@ -1117,7 +1127,7 @@ int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, 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); @@ -1126,7 +1136,7 @@ int reada_tree_block_flagged(struct btrfs_root *root, u64 bytenr, 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)) { @@ -1154,14 +1164,16 @@ 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, @@ -1191,7 +1203,8 @@ void clean_tree_block(struct btrfs_trans_handle *trans, 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); @@ -3949,7 +3962,7 @@ 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) @@ -3974,10 +3987,10 @@ 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_HEAD_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, " @@ -4031,7 +4044,8 @@ 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); } @@ -4366,7 +4380,7 @@ 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 84e060e..b8df911 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -6849,7 +6849,7 @@ 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, 0); @@ -6867,7 +6867,7 @@ 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); } /* Can return -ENOMEM */ @@ -7907,7 +7907,7 @@ 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->fs_info, buf); - clear_bit(EXTENT_BUFFER_STALE, &buf->bflags); + clear_bit(EXTENT_BUFFER_STALE, &buf->ebflags); btrfs_set_lock_blocking(buf); set_extent_buffer_uptodate(buf); diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 790ad09..4a62196 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -22,6 +22,7 @@ #include "backref.h" static struct kmem_cache *extent_state_cache; +static struct kmem_cache *extent_buffer_head_cache; static struct kmem_cache *extent_buffer_cache; static struct bio_set *btrfs_bioset; @@ -61,6 +62,7 @@ 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); @@ -73,12 +75,17 @@ 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); } } @@ -167,11 +174,17 @@ int __init extent_io_init(void) if (!extent_state_cache) return -ENOMEM; + extent_buffer_head_cache = kmem_cache_create("btrfs_extent_buffer_head", + sizeof(struct extent_buffer_head), 0, + SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); + if (!extent_buffer_head_cache) + goto free_state_cache; + extent_buffer_cache = kmem_cache_create("btrfs_extent_buffer", sizeof(struct extent_buffer), 0, SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); if (!extent_buffer_cache) - goto free_state_cache; + goto free_buffer_head_cache; btrfs_bioset = bioset_create(BIO_POOL_SIZE, offsetof(struct btrfs_io_bio, bio)); @@ -191,6 +204,10 @@ free_buffer_cache: kmem_cache_destroy(extent_buffer_cache); extent_buffer_cache = NULL; +free_buffer_head_cache: + kmem_cache_destroy(extent_buffer_head_cache); + extent_buffer_head_cache = NULL; + free_state_cache: kmem_cache_destroy(extent_state_cache); extent_state_cache = NULL; @@ -2153,7 +2170,7 @@ int repair_eb_io_failure(struct btrfs_root *root, struct extent_buffer *eb, return -EROFS; for (i = 0; i < num_pages; i++) { - struct page *p = eb->pages[i]; + struct page *p = eb_head(eb)->pages[i]; ret = repair_io_failure(root->fs_info->btree_inode, start, PAGE_SIZE, start, p, @@ -3631,8 +3648,8 @@ done_unlocked: void wait_on_extent_buffer_writeback(struct extent_buffer *eb) { - wait_on_bit_io(&eb->bflags, EXTENT_BUFFER_WRITEBACK, - TASK_UNINTERRUPTIBLE); + wait_on_bit_io(&eb->ebflags, EXTENT_BUFFER_WRITEBACK, + TASK_UNINTERRUPTIBLE); } static noinline_for_stack int @@ -3650,7 +3667,7 @@ lock_extent_buffer_for_io(struct extent_buffer *eb, btrfs_tree_lock(eb); } - if (test_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags)) { + if (test_bit(EXTENT_BUFFER_WRITEBACK, &eb->ebflags)) { btrfs_tree_unlock(eb); if (!epd->sync_io) return 0; @@ -3661,7 +3678,7 @@ lock_extent_buffer_for_io(struct extent_buffer *eb, while (1) { wait_on_extent_buffer_writeback(eb); btrfs_tree_lock(eb); - if (!test_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags)) + if (!test_bit(EXTENT_BUFFER_WRITEBACK, &eb->ebflags)) break; btrfs_tree_unlock(eb); } @@ -3672,17 +3689,17 @@ lock_extent_buffer_for_io(struct extent_buffer *eb, * under IO since we can end up having no IO bits set for a short period * of time. */ - spin_lock(&eb->refs_lock); - if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->bflags)) { - set_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags); - spin_unlock(&eb->refs_lock); + spin_lock(&eb_head(eb)->refs_lock); + if (test_and_clear_bit(EXTENT_BUFFER_DIRTY, &eb->ebflags)) { + set_bit(EXTENT_BUFFER_WRITEBACK, &eb->ebflags); + spin_unlock(&eb_head(eb)->refs_lock); btrfs_set_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN); __percpu_counter_add(&fs_info->dirty_metadata_bytes, -eb->len, fs_info->dirty_metadata_batch); ret = 1; } else { - spin_unlock(&eb->refs_lock); + spin_unlock(&eb_head(eb)->refs_lock); } btrfs_tree_unlock(eb); @@ -3692,7 +3709,7 @@ lock_extent_buffer_for_io(struct extent_buffer *eb, num_pages = num_extent_pages(eb->start, eb->len); for (i = 0; i < num_pages; i++) { - struct page *p = eb->pages[i]; + struct page *p = eb_head(eb)->pages[i]; if (!trylock_page(p)) { if (!flush) { @@ -3708,18 +3725,19 @@ lock_extent_buffer_for_io(struct extent_buffer *eb, static void end_extent_buffer_writeback(struct extent_buffer *eb) { - clear_bit(EXTENT_BUFFER_WRITEBACK, &eb->bflags); + clear_bit(EXTENT_BUFFER_WRITEBACK, &eb->ebflags); smp_mb__after_atomic(); - wake_up_bit(&eb->bflags, EXTENT_BUFFER_WRITEBACK); + wake_up_bit(&eb->ebflags, EXTENT_BUFFER_WRITEBACK); } static void set_btree_ioerr(struct page *page) { struct extent_buffer *eb = (struct extent_buffer *)page->private; - struct btrfs_inode *btree_ino = BTRFS_I(eb->fs_info->btree_inode); + struct extent_buffer_head *ebh = eb_head(eb); + struct btrfs_inode *btree_ino = BTRFS_I(ebh->fs_info->btree_inode); SetPageError(page); - if (test_and_set_bit(EXTENT_BUFFER_WRITE_ERR, &eb->bflags)) + if (test_and_set_bit(EXTENT_BUFFER_WRITE_ERR, &eb->ebflags)) return; /* @@ -3786,10 +3804,10 @@ static void end_bio_extent_buffer_writepage(struct bio *bio) eb = (struct extent_buffer *)page->private; BUG_ON(!eb); - done = atomic_dec_and_test(&eb->io_pages); + done = atomic_dec_and_test(&eb_head(eb)->io_bvecs); if (bio->bi_error || - test_bit(EXTENT_BUFFER_WRITE_ERR, &eb->bflags)) { + test_bit(EXTENT_BUFFER_WRITE_ERR, &eb->ebflags)) { ClearPageUptodate(page); set_btree_ioerr(page); } @@ -3818,14 +3836,14 @@ static noinline_for_stack int write_one_eb(struct extent_buffer *eb, int rw = (epd->sync_io ? WRITE_SYNC : WRITE) | REQ_META; int ret = 0; - clear_bit(EXTENT_BUFFER_WRITE_ERR, &eb->bflags); + clear_bit(EXTENT_BUFFER_WRITE_ERR, &eb->ebflags); num_pages = num_extent_pages(eb->start, eb->len); - atomic_set(&eb->io_pages, num_pages); + atomic_set(&eb_head(eb)->io_bvecs, num_pages); if (btrfs_header_owner(eb) == BTRFS_TREE_LOG_OBJECTID) bio_flags = EXTENT_BIO_TREE_LOG; for (i = 0; i < num_pages; i++) { - struct page *p = eb->pages[i]; + struct page *p = eb_head(eb)->pages[i]; clear_page_dirty_for_io(p); set_page_writeback(p); @@ -3837,7 +3855,8 @@ static noinline_for_stack int write_one_eb(struct extent_buffer *eb, if (ret) { set_btree_ioerr(p); end_page_writeback(p); - if (atomic_sub_and_test(num_pages - i, &eb->io_pages)) + if (atomic_sub_and_test(num_pages - i, + &eb_head(eb)->io_bvecs)) end_extent_buffer_writeback(eb); ret = -EIO; break; @@ -3849,7 +3868,7 @@ static noinline_for_stack int write_one_eb(struct extent_buffer *eb, if (unlikely(ret)) { for (; i < num_pages; i++) { - struct page *p = eb->pages[i]; + struct page *p = eb_head(eb)->pages[i]; clear_page_dirty_for_io(p); unlock_page(p); } @@ -3937,7 +3956,7 @@ retry: continue; } - ret = atomic_inc_not_zero(&eb->refs); + ret = atomic_inc_not_zero(&eb_head(eb)->refs); spin_unlock(&mapping->private_lock); if (!ret) continue; @@ -4615,17 +4634,36 @@ 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; + kmem_cache_free(extent_buffer_cache, eb); + eb = next_eb; + } + + kmem_cache_free(extent_buffer_head_cache, ebh); } 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; + break; + } + } + + return (atomic_read(&ebh->io_bvecs) || dirty_or_writeback); } /* @@ -4635,7 +4673,8 @@ static void btrfs_release_extent_buffer_page(struct extent_buffer *eb) { unsigned long index; 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_HEAD_DUMMY, &ebh->bflags); BUG_ON(extent_buffer_under_io(eb)); @@ -4644,8 +4683,11 @@ static void btrfs_release_extent_buffer_page(struct extent_buffer *eb) return; do { + struct extent_buffer *e; + index--; - page = eb->pages[index]; + + page = ebh->pages[index]; if (!page) continue; if (mapped) @@ -4658,8 +4700,10 @@ 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)); /* @@ -4686,20 +4730,18 @@ 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); - __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) +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, GFP_NOFS|__GFP_NOFAIL); 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); @@ -4710,12 +4752,27 @@ __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); +} - btrfs_leak_debug_add(&eb->leak_list, &buffers); +static struct extent_buffer * +__alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start, + unsigned long len) +{ + struct extent_buffer_head *ebh = NULL; + struct extent_buffer *cur_eb, *prev_eb; + struct extent_buffer *eb = NULL; + int i; + + ebh = kmem_cache_zalloc(extent_buffer_head_cache, GFP_NOFS|__GFP_NOFAIL); + 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 @@ -4724,7 +4781,44 @@ __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_SIZE) { + int ebs_per_page = PAGE_SIZE / len; + u64 st = start & ~(PAGE_SIZE - 1); + + prev_eb = NULL; + cur_eb = &ebh->eb; + for (i = 0; i < ebs_per_page; i++, st += len) { + if (prev_eb) { + cur_eb = kmem_cache_zalloc(extent_buffer_cache, + GFP_NOFS|__GFP_NOFAIL); + if (cur_eb == NULL) + goto out; + 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; + +out: + cur_eb = ebh->eb.eb_next; + while (cur_eb) { + prev_eb = cur_eb; + cur_eb = cur_eb->eb_next; + kmem_cache_free(extent_buffer_cache, prev_eb); + } + + kmem_cache_free(extent_buffer_head_cache, ebh); + + return NULL; } struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src) @@ -4734,7 +4828,8 @@ struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src) struct extent_buffer *new; unsigned long num_pages = num_extent_pages(src->start, src->len); - new = __alloc_extent_buffer(src->fs_info, src->start, src->len); + new = __alloc_extent_buffer(eb_head(src)->fs_info, src->start, + src->len); if (new == NULL) return NULL; @@ -4744,15 +4839,25 @@ 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; } + /* + * copy_extent_buffer() now checks for the presence of + * EXTENT_BUFFER_UPTODATE flag (instead of the page's + * PG_Uptodate flag) in dst extent buffer. Hence we set + * EXTENT_BUFFER_UPTODATE bit before copy_extent_buffer() + * is invoked. It is safe since this is the only function + * that has a reference to the just allocated dummy extent + * buffer. + */ + set_bit(EXTENT_BUFFER_UPTODATE, &new->ebflags); + set_bit(EXTENT_BUFFER_HEAD_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; } @@ -4771,19 +4876,19 @@ struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info, 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_HEAD_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; } @@ -4828,14 +4933,16 @@ 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_HEAD_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_HEAD_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, @@ -4847,44 +4954,67 @@ static void mark_extent_buffer_accessed(struct extent_buffer *eb, num_pages = num_extent_pages(eb->start, eb->len); for (i = 0; i < num_pages; i++) { - struct page *p = eb->pages[i]; + struct page *p = eb_head(eb)->pages[i]; if (p != accessed) mark_page_accessed(p); } } +static int extent_buffer_head_stale(struct extent_buffer_head *ebh) +{ + struct extent_buffer *eb = &ebh->eb; + + do { + if (test_bit(EXTENT_BUFFER_STALE, &eb->ebflags)) + return 1; + } while ((eb = eb->eb_next) != NULL); + + return 0; +} + 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_SHIFT); - if (eb && atomic_inc_not_zero(&eb->refs)) { + ebh = radix_tree_lookup(&fs_info->buffer_radix, + start >> PAGE_SHIFT); + if (ebh && atomic_inc_not_zero(&ebh->refs)) { rcu_read_unlock(); /* - * Lock our eb's refs_lock to avoid races with - * free_extent_buffer. When we get our eb it might be flagged - * with EXTENT_BUFFER_STALE and another task running - * free_extent_buffer might have seen that flag set, - * eb->refs == 2, that the buffer isn't under IO (dirty and - * writeback flags not set) and it's still in the tree (flag - * EXTENT_BUFFER_TREE_REF set), therefore being in the process - * of decrementing the extent buffer's reference count twice. - * So here we could race and increment the eb's reference count, - * clear its stale flag, mark it as dirty and drop our reference - * before the other task finishes executing free_extent_buffer, - * which would later result in an attempt to free an extent - * buffer that is dirty. + * Lock our ebh's refs_lock to avoid races with + * free_extent_buffer. When we get our eb it might be + * flagged with EXTENT_BUFFER_STALE and another task + * running free_extent_buffer might have seen that + * flag set, ebh->refs == 2, that the buffer isn't + * under IO (dirty and writeback flags not set) and + * it's still in the tree (flag + * EXTENT_BUFFER_HEAD_TREE_REF set), therefore being + * in the process of decrementing the extent buffer's + * reference count twice. So here we could race and + * increment the ebh's reference count, clear its + * stale flag, mark it as dirty and drop our reference + * before the other task finishes executing + * free_extent_buffer, which would later result in an + * attempt to free an extent buffer head (along with + * its extent buffers) that has a dirty extent buffer. */ - if (test_bit(EXTENT_BUFFER_STALE, &eb->bflags)) { - spin_lock(&eb->refs_lock); - spin_unlock(&eb->refs_lock); - } - mark_extent_buffer_accessed(eb, NULL); - return eb; + eb = &ebh->eb; + do { + if (eb->start == start) { + if (extent_buffer_head_stale(ebh)) { + spin_lock(&ebh->refs_lock); + spin_unlock(&ebh->refs_lock); + } + mark_extent_buffer_accessed(eb, NULL); + return eb; + } + } while ((eb = eb->eb_next) != NULL); + + BUG(); } rcu_read_unlock(); @@ -4922,7 +5052,7 @@ again: goto again; } check_buffer_tree_ref(eb); - set_bit(EXTENT_BUFFER_IN_TREE, &eb->bflags); + set_bit(EXTENT_BUFFER_HEAD_IN_TREE, &eb->bflags); /* * We will free dummy extent buffer's if they come into @@ -4945,7 +5075,7 @@ 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_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; @@ -4975,12 +5105,18 @@ 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); put_page(p); - mark_extent_buffer_accessed(exists, p); - goto free_eb; + do { + if (exists->start == start) { + mark_extent_buffer_accessed(exists, p); + goto free_eb; + } + } while ((exists = exists->eb_next) != NULL); + + BUG(); } exists = NULL; @@ -4992,10 +5128,11 @@ struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info, WARN_ON(PageDirty(p)); put_page(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)); - eb->pages[i] = p; + mark_page_accessed(p); + eb_head(eb)->pages[i] = p; if (!PageUptodate(p)) uptodate = 0; @@ -5004,16 +5141,22 @@ 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_SHIFT, eb); + start >> PAGE_SHIFT, eb_head(eb)); spin_unlock(&fs_info->buffer_lock); radix_tree_preload_end(); if (ret == -EEXIST) { @@ -5025,7 +5168,7 @@ again: } /* add one reference for the tree */ check_buffer_tree_ref(eb); - set_bit(EXTENT_BUFFER_IN_TREE, &eb->bflags); + set_bit(EXTENT_BUFFER_HEAD_IN_TREE, &eb_head(eb)->bflags); /* * there is a race where release page may have @@ -5036,20 +5179,20 @@ 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 = eb->pages[i]; + p = eb_head(eb)->pages[i]; ClearPageChecked(p); unlock_page(p); } - unlock_page(eb->pages[0]); + unlock_page(eb_head(eb)->pages[0]); return eb; free_eb: - WARN_ON(!atomic_dec_and_test(&eb->refs)); + WARN_ON(!atomic_dec_and_test(&eb_head(eb)->refs)); 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]); } btrfs_release_extent_buffer(eb); @@ -5058,92 +5201,111 @@ free_eb: 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_HEAD_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_SHIFT); + ebh->eb.start >> PAGE_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); + btrfs_release_extent_buffer_page(&ebh->eb); #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS - if (unlikely(test_bit(EXTENT_BUFFER_DUMMY, &eb->bflags))) { - __free_extent_buffer(eb); + if (unlikely(test_bit(EXTENT_BUFFER_HEAD_DUMMY, + &eb_head(buf)->bflags))) { + __free_extent_buffer(eb_head(eb)); return 1; } #endif - call_rcu(&eb->rcu_head, btrfs_release_extent_buffer_rcu); + 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_HEAD_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_HEAD_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_HEAD_TREE_REF, &ebh->bflags)) + atomic_dec(&ebh->refs); - 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); + 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); + + return 1; } void clear_extent_buffer_dirty(struct extent_buffer *eb) @@ -5154,8 +5316,11 @@ void clear_extent_buffer_dirty(struct extent_buffer *eb) num_pages = num_extent_pages(eb->start, eb->len); + if (eb->len < PAGE_SIZE && !page_ebs_clean(eb_head(eb))) + return; + for (i = 0; i < num_pages; i++) { - page = eb->pages[i]; + page = eb_head(eb)->pages[i]; if (!PageDirty(page)) continue; @@ -5173,7 +5338,7 @@ 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) @@ -5184,14 +5349,14 @@ 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_HEAD_TREE_REF, &eb_head(eb)->bflags)); for (i = 0; i < num_pages; i++) - set_page_dirty(eb->pages[i]); + set_page_dirty(eb_head(eb)->pages[i]); return was_dirty; } @@ -5201,10 +5366,10 @@ void clear_extent_buffer_uptodate(struct extent_buffer *eb) struct page *page; unsigned long num_pages; - clear_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); + clear_bit(EXTENT_BUFFER_UPTODATE, &eb->ebflags); num_pages = num_extent_pages(eb->start, eb->len); for (i = 0; i < num_pages; i++) { - page = eb->pages[i]; + page = eb_head(eb)->pages[i]; if (page) ClearPageUptodate(page); } @@ -5212,21 +5377,41 @@ void clear_extent_buffer_uptodate(struct extent_buffer *eb) void 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 = eb->pages[i]; - SetPageUptodate(page); + ebh = eb->ebh; + + set_bit(EXTENT_BUFFER_UPTODATE, &eb->ebflags); + if (eb->len < PAGE_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 = ebh->pages[0]; + SetPageUptodate(page); + } + } else { + num_pages = num_extent_pages(eb->start, eb->len); + for (i = 0; i < num_pages; i++) { + page = ebh->pages[i]; + SetPageUptodate(page); + } } } 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, @@ -5245,7 +5430,7 @@ int read_extent_buffer_pages(struct extent_io_tree *tree, struct bio *bio = NULL; unsigned long bio_flags = 0; - if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags)) + if (test_bit(EXTENT_BUFFER_UPTODATE, &eb->ebflags)) return 0; if (start) { @@ -5258,7 +5443,7 @@ int read_extent_buffer_pages(struct extent_io_tree *tree, num_pages = num_extent_pages(eb->start, eb->len); for (i = start_i; i < num_pages; i++) { - page = eb->pages[i]; + page = eb_head(eb)->pages[i]; if (wait == WAIT_NONE) { if (!trylock_page(page)) goto unlock_exit; @@ -5273,15 +5458,15 @@ int read_extent_buffer_pages(struct extent_io_tree *tree, } if (all_uptodate) { if (start_i == 0) - set_bit(EXTENT_BUFFER_UPTODATE, &eb->bflags); + set_bit(EXTENT_BUFFER_UPTODATE, &eb->ebflags); goto unlock_exit; } - clear_bit(EXTENT_BUFFER_READ_ERR, &eb->bflags); + clear_bit(EXTENT_BUFFER_READ_ERR, &eb->ebflags); eb->read_mirror = 0; - atomic_set(&eb->io_pages, num_reads); + atomic_set(&eb_head(eb)->io_bvecs, num_reads); for (i = start_i; i < num_pages; i++) { - page = eb->pages[i]; + page = eb_head(eb)->pages[i]; if (!PageUptodate(page)) { ClearPageError(page); err = __extent_read_full_page(tree, page, @@ -5306,7 +5491,7 @@ int read_extent_buffer_pages(struct extent_io_tree *tree, return ret; for (i = start_i; i < num_pages; i++) { - page = eb->pages[i]; + page = eb_head(eb)->pages[i]; wait_on_page_locked(page); if (!PageUptodate(page)) ret = -EIO; @@ -5317,7 +5502,7 @@ int read_extent_buffer_pages(struct extent_io_tree *tree, unlock_exit: i = start_i; while (locked_pages > 0) { - page = eb->pages[i]; + page = eb_head(eb)->pages[i]; i++; unlock_page(page); locked_pages--; @@ -5343,7 +5528,7 @@ void read_extent_buffer(struct extent_buffer *eb, void *dstv, offset = (start_offset + start) & (PAGE_SIZE - 1); while (len > 0) { - page = eb->pages[i]; + page = eb_head(eb)->pages[i]; cur = min(len, (PAGE_SIZE - offset)); kaddr = page_address(page); @@ -5375,7 +5560,7 @@ int read_extent_buffer_to_user(struct extent_buffer *eb, void __user *dstv, offset = (start_offset + start) & (PAGE_SIZE - 1); while (len > 0) { - page = eb->pages[i]; + page = eb_head(eb)->pages[i]; cur = min(len, (PAGE_SIZE - offset)); kaddr = page_address(page); @@ -5424,7 +5609,7 @@ int map_private_extent_buffer(struct extent_buffer *eb, unsigned long start, return -EINVAL; } - p = eb->pages[i]; + p = eb_head(eb)->pages[i]; kaddr = page_address(p); *map = kaddr + offset; *map_len = PAGE_SIZE - offset; @@ -5450,7 +5635,7 @@ int memcmp_extent_buffer(struct extent_buffer *eb, const void *ptrv, offset = (start_offset + start) & (PAGE_SIZE - 1); while (len > 0) { - page = eb->pages[i]; + page = eb_head(eb)->pages[i]; cur = min(len, (PAGE_SIZE - offset)); @@ -5480,12 +5665,12 @@ void write_extent_buffer(struct extent_buffer *eb, const void *srcv, 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_SIZE - 1); while (len > 0) { - page = eb->pages[i]; - WARN_ON(!PageUptodate(page)); + page = eb_head(eb)->pages[i]; cur = min(len, PAGE_SIZE - offset); kaddr = page_address(page); @@ -5513,9 +5698,10 @@ void memset_extent_buffer(struct extent_buffer *eb, char c, offset = (start_offset + start) & (PAGE_SIZE - 1); + WARN_ON(!test_bit(EXTENT_BUFFER_UPTODATE, &eb->ebflags)); + while (len > 0) { - page = eb->pages[i]; - WARN_ON(!PageUptodate(page)); + page = eb_head(eb)->pages[i]; cur = min(len, PAGE_SIZE - offset); kaddr = page_address(page); @@ -5544,9 +5730,10 @@ void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, offset = (start_offset + dst_offset) & (PAGE_SIZE - 1); + WARN_ON(!test_bit(EXTENT_BUFFER_UPTODATE, &dst->ebflags)); + while (len > 0) { - page = dst->pages[i]; - WARN_ON(!PageUptodate(page)); + page = eb_head(dst)->pages[i]; cur = min(len, (unsigned long)(PAGE_SIZE - offset)); @@ -5620,7 +5807,7 @@ int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start, size_t offset; eb_bitmap_offset(eb, start, nr, &i, &offset); - page = eb->pages[i]; + page = eb_head(eb)->pages[i]; WARN_ON(!PageUptodate(page)); kaddr = page_address(page); return 1U & (kaddr[offset] >> (nr & (BITS_PER_BYTE - 1))); @@ -5645,7 +5832,7 @@ void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start, unsigned int mask_to_set = BITMAP_FIRST_BYTE_MASK(pos); eb_bitmap_offset(eb, start, pos, &i, &offset); - page = eb->pages[i]; + page = eb_head(eb)->pages[i]; WARN_ON(!PageUptodate(page)); kaddr = page_address(page); @@ -5656,7 +5843,7 @@ void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start, mask_to_set = ~0U; if (++offset >= PAGE_SIZE && len > 0) { offset = 0; - page = eb->pages[++i]; + page = eb_head(eb)->pages[++i]; WARN_ON(!PageUptodate(page)); kaddr = page_address(page); } @@ -5687,7 +5874,7 @@ void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start, unsigned int mask_to_clear = BITMAP_FIRST_BYTE_MASK(pos); eb_bitmap_offset(eb, start, pos, &i, &offset); - page = eb->pages[i]; + page = eb_head(eb)->pages[i]; WARN_ON(!PageUptodate(page)); kaddr = page_address(page); @@ -5698,7 +5885,7 @@ void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start, mask_to_clear = ~0U; if (++offset >= PAGE_SIZE && len > 0) { offset = 0; - page = eb->pages[++i]; + page = eb_head(eb)->pages[++i]; WARN_ON(!PageUptodate(page)); kaddr = page_address(page); } @@ -5748,13 +5935,13 @@ void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, unsigned long src_i; if (src_offset + len > dst->len) { - btrfs_err(dst->fs_info, + btrfs_err(eb_head(dst)->fs_info, "memmove bogus src_offset %lu move " "len %lu dst len %lu", src_offset, len, dst->len); BUG_ON(1); } if (dst_offset + len > dst->len) { - btrfs_err(dst->fs_info, + btrfs_err(eb_head(dst)->fs_info, "memmove bogus dst_offset %lu move " "len %lu dst len %lu", dst_offset, len, dst->len); BUG_ON(1); @@ -5774,8 +5961,9 @@ void memcpy_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, cur = min_t(unsigned long, cur, (unsigned long)(PAGE_SIZE - dst_off_in_page)); - copy_pages(dst->pages[dst_i], dst->pages[src_i], - dst_off_in_page, src_off_in_page, cur); + copy_pages(eb_head(dst)->pages[dst_i], + eb_head(dst)->pages[src_i], + dst_off_in_page, src_off_in_page, cur); src_offset += cur; dst_offset += cur; @@ -5796,13 +5984,15 @@ void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, unsigned long src_i; if (src_offset + len > dst->len) { - btrfs_err(dst->fs_info, "memmove bogus src_offset %lu move " - "len %lu len %lu", src_offset, len, dst->len); + btrfs_err(eb_head(dst)->fs_info, + "memmove bogus src_offset %lu move len %lu len %lu", + src_offset, len, dst->len); BUG_ON(1); } if (dst_offset + len > dst->len) { - btrfs_err(dst->fs_info, "memmove bogus dst_offset %lu move " - "len %lu len %lu", dst_offset, len, dst->len); + btrfs_err(eb_head(dst)->fs_info, + "memmove bogus dst_offset %lu move len %lu len %lu", + dst_offset, len, dst->len); BUG_ON(1); } if (dst_offset < src_offset) { @@ -5820,9 +6010,10 @@ void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, cur = min_t(unsigned long, len, src_off_in_page + 1); cur = min(cur, dst_off_in_page + 1); - copy_pages(dst->pages[dst_i], dst->pages[src_i], - dst_off_in_page - cur + 1, - src_off_in_page - cur + 1, cur); + copy_pages(eb_head(dst)->pages[dst_i], + eb_head(dst)->pages[src_i], + dst_off_in_page - cur + 1, + src_off_in_page - cur + 1, cur); dst_end -= cur; src_end -= cur; @@ -5832,6 +6023,7 @@ 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; /* @@ -5847,14 +6039,15 @@ 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; } @@ -5864,10 +6057,11 @@ 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_HEAD_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 026befc..1996e08 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -31,18 +31,20 @@ #define EXTENT_BIO_TREE_LOG 2 #define EXTENT_BIO_FLAG_SHIFT 16 -/* these are bit numbers for test/set bit */ +/* these are bit numbers for test/set bit on extent buffer head */ +#define EXTENT_BUFFER_HEAD_TREE_REF 0 +#define EXTENT_BUFFER_HEAD_DUMMY 1 +#define EXTENT_BUFFER_HEAD_IN_TREE 2 + +/* these are bit numbers for test/set bit on extent buffer */ #define EXTENT_BUFFER_UPTODATE 0 -#define EXTENT_BUFFER_DIRTY 2 -#define EXTENT_BUFFER_CORRUPT 3 -#define EXTENT_BUFFER_READAHEAD 4 /* this got triggered by readahead */ -#define EXTENT_BUFFER_TREE_REF 5 -#define EXTENT_BUFFER_STALE 6 -#define EXTENT_BUFFER_WRITEBACK 7 -#define EXTENT_BUFFER_READ_ERR 8 /* read IO error */ -#define EXTENT_BUFFER_DUMMY 9 -#define EXTENT_BUFFER_IN_TREE 10 -#define EXTENT_BUFFER_WRITE_ERR 11 /* write IO error */ +#define EXTENT_BUFFER_DIRTY 1 +#define EXTENT_BUFFER_CORRUPT 2 +#define EXTENT_BUFFER_READAHEAD 3 /* this got triggered by readahead */ +#define EXTENT_BUFFER_STALE 4 +#define EXTENT_BUFFER_WRITEBACK 5 +#define EXTENT_BUFFER_READ_ERR 6 /* read IO error */ +#define EXTENT_BUFFER_WRITE_ERR 7 /* write IO error */ /* these are flags for extent_clear_unlock_delalloc */ #define PAGE_UNLOCK (1 << 0) @@ -174,17 +176,17 @@ struct extent_state { #define INLINE_EXTENT_BUFFER_PAGES 16 #define MAX_INLINE_EXTENT_BUFFER_SIZE (INLINE_EXTENT_BUFFER_PAGES * PAGE_SIZE) + +/* Forward declaration */ +struct extent_buffer_head; + struct extent_buffer { u64 start; unsigned long 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; @@ -197,6 +199,8 @@ struct extent_buffer { /* >= 0 if eb belongs to a log tree, -1 otherwise */ short log_index; + pid_t lock_owner; + /* protects write locks */ rwlock_t lock; @@ -209,7 +213,20 @@ struct extent_buffer { * to unlock */ 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 @@ -237,6 +254,14 @@ 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, @@ -430,7 +455,7 @@ static inline unsigned long num_extent_pages(u64 start, u64 len) 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/root-tree.c b/fs/btrfs/root-tree.c index 9fcd6df..2b6024f 100644 --- a/fs/btrfs/root-tree.c +++ b/fs/btrfs/root-tree.c @@ -45,7 +45,7 @@ static void btrfs_read_root_item(struct extent_buffer *eb, int slot, if (!need_reset && btrfs_root_generation(item) != btrfs_root_generation_v2(item)) { if (btrfs_root_generation_v2(item) != 0) { - btrfs_warn(eb->fs_info, + btrfs_warn(eb_head(eb)->fs_info, "mismatching " "generation and generation_v2 " "found in root item. This root " diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index bd0f45f..f6aa4f5 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -6528,7 +6528,7 @@ int btrfs_read_sys_array(struct btrfs_root *root) * to silence the warning eg. on PowerPC 64. */ if (PAGE_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 e90e82a..4fc0b40 100644 --- a/include/trace/events/btrfs.h +++ b/include/trace/events/btrfs.h @@ -700,7 +700,7 @@ 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);