--- /dev/null
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Changwei Ge <ge.changwei@h3c.com>
+Date: Wed, 31 Jan 2018 16:15:02 -0800
+Subject: [PATCH] ocfs2: make metadata estimation accurate and clear
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Current code assume that ::w_unwritten_list always has only one item on.
+This is not right and hard to get understood. So improve how to count
+unwritten item.
+
+Link: http://lkml.kernel.org/r/1515479070-32653-1-git-send-email-ge.changwei@h3c.com
+Signed-off-by: Changwei Ge <ge.changwei@h3c.com>
+Reported-by: John Lightsey <john@nixnuts.net>
+Tested-by: John Lightsey <john@nixnuts.net>
+Cc: Mark Fasheh <mfasheh@versity.com>
+Cc: Joseph Qi <jiangqi903@gmail.com>
+Cc: Junxiao Bi <junxiao.bi@oracle.com>
+Cc: Joel Becker <jlbec@evilplan.org>
+Cc: Changwei Ge <ge.changwei@h3c.com>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+(cherry picked from commit 63de8bd9328bf2a778fc277503da163ae3defa3c)
+Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
+---
+ fs/ocfs2/aops.c | 4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
+index 88a31e9340a0..77ec9b495027 100644
+--- a/fs/ocfs2/aops.c
++++ b/fs/ocfs2/aops.c
+@@ -784,6 +784,7 @@ struct ocfs2_write_ctxt {
+ struct ocfs2_cached_dealloc_ctxt w_dealloc;
+
+ struct list_head w_unwritten_list;
++ unsigned int w_unwritten_count;
+ };
+
+ void ocfs2_unlock_and_free_pages(struct page **pages, int num_pages)
+@@ -1373,6 +1374,7 @@ static int ocfs2_unwritten_check(struct inode *inode,
+ desc->c_clear_unwritten = 0;
+ list_add_tail(&new->ue_ip_node, &oi->ip_unwritten_list);
+ list_add_tail(&new->ue_node, &wc->w_unwritten_list);
++ wc->w_unwritten_count++;
+ new = NULL;
+ unlock:
+ spin_unlock(&oi->ip_lock);
+@@ -2246,7 +2248,7 @@ static int ocfs2_dio_get_block(struct inode *inode, sector_t iblock,
+ ue->ue_phys = desc->c_phys;
+
+ list_splice_tail_init(&wc->w_unwritten_list, &dwc->dw_zero_list);
+- dwc->dw_zero_count++;
++ dwc->dw_zero_count += wc->w_unwritten_count;
+ }
+
+ ret = ocfs2_write_end_nolock(inode->i_mapping, pos, len, len, wc);
+--
+2.14.2
+
--- /dev/null
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Changwei Ge <ge.changwei@h3c.com>
+Date: Wed, 31 Jan 2018 16:15:06 -0800
+Subject: [PATCH] ocfs2: try to reuse extent block in dealloc without
+ meta_alloc
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+A crash issue was reported by John Lightsey with a call trace as follows:
+
+ ocfs2_split_extent+0x1ad3/0x1b40 [ocfs2]
+ ocfs2_change_extent_flag+0x33a/0x470 [ocfs2]
+ ocfs2_mark_extent_written+0x172/0x220 [ocfs2]
+ ocfs2_dio_end_io+0x62d/0x910 [ocfs2]
+ dio_complete+0x19a/0x1a0
+ do_blockdev_direct_IO+0x19dd/0x1eb0
+ __blockdev_direct_IO+0x43/0x50
+ ocfs2_direct_IO+0x8f/0xa0 [ocfs2]
+ generic_file_direct_write+0xb2/0x170
+ __generic_file_write_iter+0xc3/0x1b0
+ ocfs2_file_write_iter+0x4bb/0xca0 [ocfs2]
+ __vfs_write+0xae/0xf0
+ vfs_write+0xb8/0x1b0
+ SyS_write+0x4f/0xb0
+ system_call_fastpath+0x16/0x75
+
+The BUG code told that extent tree wants to grow but no metadata was
+reserved ahead of time. From my investigation into this issue, the root
+cause it that although enough metadata is not reserved, there should be
+enough for following use. Rightmost extent is merged into its left one
+due to a certain times of marking extent written. Because during
+marking extent written, we got many physically continuous extents. At
+last, an empty extent showed up and the rightmost path is removed from
+extent tree.
+
+Add a new mechanism to reuse extent block cached in dealloc which were
+just unlinked from extent tree to solve this crash issue.
+
+Criteria is that during marking extents *written*, if extent rotation
+and merging results in unlinking extent with growing extent tree later
+without any metadata reserved ahead of time, try to reuse those extents
+in dealloc in which deleted extents are cached.
+
+Also, this patch addresses the issue John reported that ::dw_zero_count
+is not calculated properly.
+
+After applying this patch, the issue John reported was gone. Thanks for
+the reproducer provided by John. And this patch has passed
+ocfs2-test(29 cases) suite running by New H3C Group.
+
+[ge.changwei@h3c.com: fix static checker warnning]
+ Link: http://lkml.kernel.org/r/63ADC13FD55D6546B7DECE290D39E373F29196AE@H3CMLB12-EX.srv.huawei-3com.com
+[akpm@linux-foundation.org: brelse(NULL) is legal]
+Link: http://lkml.kernel.org/r/1515479070-32653-2-git-send-email-ge.changwei@h3c.com
+Signed-off-by: Changwei Ge <ge.changwei@h3c.com>
+Reported-by: John Lightsey <john@nixnuts.net>
+Tested-by: John Lightsey <john@nixnuts.net>
+Cc: Joel Becker <jlbec@evilplan.org>
+Cc: Joseph Qi <jiangqi903@gmail.com>
+Cc: Junxiao Bi <junxiao.bi@oracle.com>
+Cc: Dan Carpenter <dan.carpenter@oracle.com>
+Cc: Mark Fasheh <mfasheh@versity.com>
+Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
+Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
+(cherry picked from commit 71a36944042b7d9dd71f6a5d1c5ea1c2353b5d42)
+Signed-off-by: Fabian Grünbichler <f.gruenbichler@proxmox.com>
+---
+ fs/ocfs2/alloc.h | 1 +
+ fs/ocfs2/alloc.c | 206 ++++++++++++++++++++++++++++++++++++++++++++++++++++---
+ fs/ocfs2/aops.c | 6 ++
+ 3 files changed, 203 insertions(+), 10 deletions(-)
+
+diff --git a/fs/ocfs2/alloc.h b/fs/ocfs2/alloc.h
+index 4a5152ec88a3..571692171dd1 100644
+--- a/fs/ocfs2/alloc.h
++++ b/fs/ocfs2/alloc.h
+@@ -61,6 +61,7 @@ struct ocfs2_extent_tree {
+ ocfs2_journal_access_func et_root_journal_access;
+ void *et_object;
+ unsigned int et_max_leaf_clusters;
++ struct ocfs2_cached_dealloc_ctxt *et_dealloc;
+ };
+
+ /*
+diff --git a/fs/ocfs2/alloc.c b/fs/ocfs2/alloc.c
+index 386aecce881d..9b5e7d8ba710 100644
+--- a/fs/ocfs2/alloc.c
++++ b/fs/ocfs2/alloc.c
+@@ -165,6 +165,13 @@ static int ocfs2_dinode_insert_check(struct ocfs2_extent_tree *et,
+ struct ocfs2_extent_rec *rec);
+ static int ocfs2_dinode_sanity_check(struct ocfs2_extent_tree *et);
+ static void ocfs2_dinode_fill_root_el(struct ocfs2_extent_tree *et);
++
++static int ocfs2_reuse_blk_from_dealloc(handle_t *handle,
++ struct ocfs2_extent_tree *et,
++ struct buffer_head **new_eb_bh,
++ int blk_wanted, int *blk_given);
++static int ocfs2_is_dealloc_empty(struct ocfs2_extent_tree *et);
++
+ static const struct ocfs2_extent_tree_operations ocfs2_dinode_et_ops = {
+ .eo_set_last_eb_blk = ocfs2_dinode_set_last_eb_blk,
+ .eo_get_last_eb_blk = ocfs2_dinode_get_last_eb_blk,
+@@ -448,6 +455,7 @@ static void __ocfs2_init_extent_tree(struct ocfs2_extent_tree *et,
+ if (!obj)
+ obj = (void *)bh->b_data;
+ et->et_object = obj;
++ et->et_dealloc = NULL;
+
+ et->et_ops->eo_fill_root_el(et);
+ if (!et->et_ops->eo_fill_max_leaf_clusters)
+@@ -1159,7 +1167,7 @@ static int ocfs2_add_branch(handle_t *handle,
+ struct buffer_head **last_eb_bh,
+ struct ocfs2_alloc_context *meta_ac)
+ {
+- int status, new_blocks, i;
++ int status, new_blocks, i, block_given = 0;
+ u64 next_blkno, new_last_eb_blk;
+ struct buffer_head *bh;
+ struct buffer_head **new_eb_bhs = NULL;
+@@ -1214,11 +1222,31 @@ static int ocfs2_add_branch(handle_t *handle,
+ goto bail;
+ }
+
+- status = ocfs2_create_new_meta_bhs(handle, et, new_blocks,
+- meta_ac, new_eb_bhs);
+- if (status < 0) {
+- mlog_errno(status);
+- goto bail;
++ /* Firstyly, try to reuse dealloc since we have already estimated how
++ * many extent blocks we may use.
++ */
++ if (!ocfs2_is_dealloc_empty(et)) {
++ status = ocfs2_reuse_blk_from_dealloc(handle, et,
++ new_eb_bhs, new_blocks,
++ &block_given);
++ if (status < 0) {
++ mlog_errno(status);
++ goto bail;
++ }
++ }
++
++ BUG_ON(block_given > new_blocks);
++
++ if (block_given < new_blocks) {
++ BUG_ON(!meta_ac);
++ status = ocfs2_create_new_meta_bhs(handle, et,
++ new_blocks - block_given,
++ meta_ac,
++ &new_eb_bhs[block_given]);
++ if (status < 0) {
++ mlog_errno(status);
++ goto bail;
++ }
+ }
+
+ /* Note: new_eb_bhs[new_blocks - 1] is the guy which will be
+@@ -1341,15 +1369,25 @@ static int ocfs2_shift_tree_depth(handle_t *handle,
+ struct ocfs2_alloc_context *meta_ac,
+ struct buffer_head **ret_new_eb_bh)
+ {
+- int status, i;
++ int status, i, block_given = 0;
+ u32 new_clusters;
+ struct buffer_head *new_eb_bh = NULL;
+ struct ocfs2_extent_block *eb;
+ struct ocfs2_extent_list *root_el;
+ struct ocfs2_extent_list *eb_el;
+
+- status = ocfs2_create_new_meta_bhs(handle, et, 1, meta_ac,
+- &new_eb_bh);
++ if (!ocfs2_is_dealloc_empty(et)) {
++ status = ocfs2_reuse_blk_from_dealloc(handle, et,
++ &new_eb_bh, 1,
++ &block_given);
++ } else if (meta_ac) {
++ status = ocfs2_create_new_meta_bhs(handle, et, 1, meta_ac,
++ &new_eb_bh);
++
++ } else {
++ BUG();
++ }
++
+ if (status < 0) {
+ mlog_errno(status);
+ goto bail;
+@@ -1512,7 +1550,7 @@ static int ocfs2_grow_tree(handle_t *handle, struct ocfs2_extent_tree *et,
+ int depth = le16_to_cpu(el->l_tree_depth);
+ struct buffer_head *bh = NULL;
+
+- BUG_ON(meta_ac == NULL);
++ BUG_ON(meta_ac == NULL && ocfs2_is_dealloc_empty(et));
+
+ shift = ocfs2_find_branch_target(et, &bh);
+ if (shift < 0) {
+@@ -6593,6 +6631,154 @@ ocfs2_find_per_slot_free_list(int type,
+ return fl;
+ }
+
++static struct ocfs2_per_slot_free_list *
++ocfs2_find_preferred_free_list(int type,
++ int preferred_slot,
++ int *real_slot,
++ struct ocfs2_cached_dealloc_ctxt *ctxt)
++{
++ struct ocfs2_per_slot_free_list *fl = ctxt->c_first_suballocator;
++
++ while (fl) {
++ if (fl->f_inode_type == type && fl->f_slot == preferred_slot) {
++ *real_slot = fl->f_slot;
++ return fl;
++ }
++
++ fl = fl->f_next_suballocator;
++ }
++
++ /* If we can't find any free list matching preferred slot, just use
++ * the first one.
++ */
++ fl = ctxt->c_first_suballocator;
++ *real_slot = fl->f_slot;
++
++ return fl;
++}
++
++/* Return Value 1 indicates empty */
++static int ocfs2_is_dealloc_empty(struct ocfs2_extent_tree *et)
++{
++ struct ocfs2_per_slot_free_list *fl = NULL;
++
++ if (!et->et_dealloc)
++ return 1;
++
++ fl = et->et_dealloc->c_first_suballocator;
++ if (!fl)
++ return 1;
++
++ if (!fl->f_first)
++ return 1;
++
++ return 0;
++}
++
++/* If extent was deleted from tree due to extent rotation and merging, and
++ * no metadata is reserved ahead of time. Try to reuse some extents
++ * just deleted. This is only used to reuse extent blocks.
++ * It is supposed to find enough extent blocks in dealloc if our estimation
++ * on metadata is accurate.
++ */
++static int ocfs2_reuse_blk_from_dealloc(handle_t *handle,
++ struct ocfs2_extent_tree *et,
++ struct buffer_head **new_eb_bh,
++ int blk_wanted, int *blk_given)
++{
++ int i, status = 0, real_slot;
++ struct ocfs2_cached_dealloc_ctxt *dealloc;
++ struct ocfs2_per_slot_free_list *fl;
++ struct ocfs2_cached_block_free *bf;
++ struct ocfs2_extent_block *eb;
++ struct ocfs2_super *osb =
++ OCFS2_SB(ocfs2_metadata_cache_get_super(et->et_ci));
++
++ *blk_given = 0;
++
++ /* If extent tree doesn't have a dealloc, this is not faulty. Just
++ * tell upper caller dealloc can't provide any block and it should
++ * ask for alloc to claim more space.
++ */
++ dealloc = et->et_dealloc;
++ if (!dealloc)
++ goto bail;
++
++ for (i = 0; i < blk_wanted; i++) {
++ /* Prefer to use local slot */
++ fl = ocfs2_find_preferred_free_list(EXTENT_ALLOC_SYSTEM_INODE,
++ osb->slot_num, &real_slot,
++ dealloc);
++ /* If no more block can be reused, we should claim more
++ * from alloc. Just return here normally.
++ */
++ if (!fl) {
++ status = 0;
++ break;
++ }
++
++ bf = fl->f_first;
++ fl->f_first = bf->free_next;
++
++ new_eb_bh[i] = sb_getblk(osb->sb, bf->free_blk);
++ if (new_eb_bh[i] == NULL) {
++ status = -ENOMEM;
++ mlog_errno(status);
++ goto bail;
++ }
++
++ mlog(0, "Reusing block(%llu) from "
++ "dealloc(local slot:%d, real slot:%d)\n",
++ bf->free_blk, osb->slot_num, real_slot);
++
++ ocfs2_set_new_buffer_uptodate(et->et_ci, new_eb_bh[i]);
++
++ status = ocfs2_journal_access_eb(handle, et->et_ci,
++ new_eb_bh[i],
++ OCFS2_JOURNAL_ACCESS_CREATE);
++ if (status < 0) {
++ mlog_errno(status);
++ goto bail;
++ }
++
++ memset(new_eb_bh[i]->b_data, 0, osb->sb->s_blocksize);
++ eb = (struct ocfs2_extent_block *) new_eb_bh[i]->b_data;
++
++ /* We can't guarantee that buffer head is still cached, so
++ * polutlate the extent block again.
++ */
++ strcpy(eb->h_signature, OCFS2_EXTENT_BLOCK_SIGNATURE);
++ eb->h_blkno = cpu_to_le64(bf->free_blk);
++ eb->h_fs_generation = cpu_to_le32(osb->fs_generation);
++ eb->h_suballoc_slot = cpu_to_le16(real_slot);
++ eb->h_suballoc_loc = cpu_to_le64(bf->free_bg);
++ eb->h_suballoc_bit = cpu_to_le16(bf->free_bit);
++ eb->h_list.l_count =
++ cpu_to_le16(ocfs2_extent_recs_per_eb(osb->sb));
++
++ /* We'll also be dirtied by the caller, so
++ * this isn't absolutely necessary.
++ */
++ ocfs2_journal_dirty(handle, new_eb_bh[i]);
++
++ if (!fl->f_first) {
++ dealloc->c_first_suballocator = fl->f_next_suballocator;
++ kfree(fl);
++ }
++ kfree(bf);
++ }
++
++ *blk_given = i;
++
++bail:
++ if (unlikely(status < 0)) {
++ for (i = 0; i < blk_wanted; i++)
++ brelse(new_eb_bh[i]);
++ }
++
++ return status;
++}
++
+ int ocfs2_cache_block_dealloc(struct ocfs2_cached_dealloc_ctxt *ctxt,
+ int type, int slot, u64 suballoc,
+ u64 blkno, unsigned int bit)
+diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
+index 77ec9b495027..2ff02dda97d8 100644
+--- a/fs/ocfs2/aops.c
++++ b/fs/ocfs2/aops.c
+@@ -2322,6 +2322,12 @@ static int ocfs2_dio_end_io_write(struct inode *inode,
+
+ ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), di_bh);
+
++ /* Attach dealloc with extent tree in case that we may reuse extents
++ * which are already unlinked from current extent tree due to extent
++ * rotation and merging.
++ */
++ et.et_dealloc = &dealloc;
++
+ ret = ocfs2_lock_allocators(inode, &et, 0, dwc->dw_zero_count*2,
+ &data_ac, &meta_ac);
+ if (ret) {
+--
+2.14.2
+
projects / pve-kernel.git / commitdiff