diff options
Diffstat (limited to 'fs/ocfs2/refcounttree.c')
| -rw-r--r-- | fs/ocfs2/refcounttree.c | 4313 |
1 files changed, 4313 insertions, 0 deletions
diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c new file mode 100644 index 00000000000..60287fc56bc --- /dev/null +++ b/fs/ocfs2/refcounttree.c @@ -0,0 +1,4313 @@ +/* -*- mode: c; c-basic-offset: 8; -*- + * vim: noexpandtab sw=8 ts=8 sts=0: + * + * refcounttree.c + * + * Copyright (C) 2009 Oracle. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ + +#include <linux/sort.h> +#define MLOG_MASK_PREFIX ML_REFCOUNT +#include <cluster/masklog.h> +#include "ocfs2.h" +#include "inode.h" +#include "alloc.h" +#include "suballoc.h" +#include "journal.h" +#include "uptodate.h" +#include "super.h" +#include "buffer_head_io.h" +#include "blockcheck.h" +#include "refcounttree.h" +#include "sysfile.h" +#include "dlmglue.h" +#include "extent_map.h" +#include "aops.h" +#include "xattr.h" +#include "namei.h" + +#include <linux/bio.h> +#include <linux/blkdev.h> +#include <linux/gfp.h> +#include <linux/slab.h> +#include <linux/writeback.h> +#include <linux/pagevec.h> +#include <linux/swap.h> +#include <linux/security.h> +#include <linux/fsnotify.h> +#include <linux/quotaops.h> +#include <linux/namei.h> +#include <linux/mount.h> + +struct ocfs2_cow_context { + struct inode *inode; + u32 cow_start; + u32 cow_len; + struct ocfs2_extent_tree data_et; + struct ocfs2_refcount_tree *ref_tree; + struct buffer_head *ref_root_bh; + struct ocfs2_alloc_context *meta_ac; + struct ocfs2_alloc_context *data_ac; + struct ocfs2_cached_dealloc_ctxt dealloc; + void *cow_object; + struct ocfs2_post_refcount *post_refcount; + int extra_credits; + int (*get_clusters)(struct ocfs2_cow_context *context, + u32 v_cluster, u32 *p_cluster, + u32 *num_clusters, + unsigned int *extent_flags); + int (*cow_duplicate_clusters)(handle_t *handle, + struct ocfs2_cow_context *context, + u32 cpos, u32 old_cluster, + u32 new_cluster, u32 new_len); +}; + +static inline struct ocfs2_refcount_tree * +cache_info_to_refcount(struct ocfs2_caching_info *ci) +{ + return container_of(ci, struct ocfs2_refcount_tree, rf_ci); +} + +static int ocfs2_validate_refcount_block(struct super_block *sb, + struct buffer_head *bh) +{ + int rc; + struct ocfs2_refcount_block *rb = + (struct ocfs2_refcount_block *)bh->b_data; + + mlog(0, "Validating refcount block %llu\n", + (unsigned long long)bh->b_blocknr); + + BUG_ON(!buffer_uptodate(bh)); + + /* + * If the ecc fails, we return the error but otherwise + * leave the filesystem running. We know any error is + * local to this block. + */ + rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &rb->rf_check); + if (rc) { + mlog(ML_ERROR, "Checksum failed for refcount block %llu\n", + (unsigned long long)bh->b_blocknr); + return rc; + } + + + if (!OCFS2_IS_VALID_REFCOUNT_BLOCK(rb)) { + ocfs2_error(sb, + "Refcount block #%llu has bad signature %.*s", + (unsigned long long)bh->b_blocknr, 7, + rb->rf_signature); + return -EINVAL; + } + + if (le64_to_cpu(rb->rf_blkno) != bh->b_blocknr) { + ocfs2_error(sb, + "Refcount block #%llu has an invalid rf_blkno " + "of %llu", + (unsigned long long)bh->b_blocknr, + (unsigned long long)le64_to_cpu(rb->rf_blkno)); + return -EINVAL; + } + + if (le32_to_cpu(rb->rf_fs_generation) != OCFS2_SB(sb)->fs_generation) { + ocfs2_error(sb, + "Refcount block #%llu has an invalid " + "rf_fs_generation of #%u", + (unsigned long long)bh->b_blocknr, + le32_to_cpu(rb->rf_fs_generation)); + return -EINVAL; + } + + return 0; +} + +static int ocfs2_read_refcount_block(struct ocfs2_caching_info *ci, + u64 rb_blkno, + struct buffer_head **bh) +{ + int rc; + struct buffer_head *tmp = *bh; + + rc = ocfs2_read_block(ci, rb_blkno, &tmp, + ocfs2_validate_refcount_block); + + /* If ocfs2_read_block() got us a new bh, pass it up. */ + if (!rc && !*bh) + *bh = tmp; + + return rc; +} + +static u64 ocfs2_refcount_cache_owner(struct ocfs2_caching_info *ci) +{ + struct ocfs2_refcount_tree *rf = cache_info_to_refcount(ci); + + return rf->rf_blkno; +} + +static struct super_block * +ocfs2_refcount_cache_get_super(struct ocfs2_caching_info *ci) +{ + struct ocfs2_refcount_tree *rf = cache_info_to_refcount(ci); + + return rf->rf_sb; +} + +static void ocfs2_refcount_cache_lock(struct ocfs2_caching_info *ci) +{ + struct ocfs2_refcount_tree *rf = cache_info_to_refcount(ci); + + spin_lock(&rf->rf_lock); +} + +static void ocfs2_refcount_cache_unlock(struct ocfs2_caching_info *ci) +{ + struct ocfs2_refcount_tree *rf = cache_info_to_refcount(ci); + + spin_unlock(&rf->rf_lock); +} + +static void ocfs2_refcount_cache_io_lock(struct ocfs2_caching_info *ci) +{ + struct ocfs2_refcount_tree *rf = cache_info_to_refcount(ci); + + mutex_lock(&rf->rf_io_mutex); +} + +static void ocfs2_refcount_cache_io_unlock(struct ocfs2_caching_info *ci) +{ + struct ocfs2_refcount_tree *rf = cache_info_to_refcount(ci); + + mutex_unlock(&rf->rf_io_mutex); +} + +static const struct ocfs2_caching_operations ocfs2_refcount_caching_ops = { + .co_owner = ocfs2_refcount_cache_owner, + .co_get_super = ocfs2_refcount_cache_get_super, + .co_cache_lock = ocfs2_refcount_cache_lock, + .co_cache_unlock = ocfs2_refcount_cache_unlock, + .co_io_lock = ocfs2_refcount_cache_io_lock, + .co_io_unlock = ocfs2_refcount_cache_io_unlock, +}; + +static struct ocfs2_refcount_tree * +ocfs2_find_refcount_tree(struct ocfs2_super *osb, u64 blkno) +{ + struct rb_node *n = osb->osb_rf_lock_tree.rb_node; + struct ocfs2_refcount_tree *tree = NULL; + + while (n) { + tree = rb_entry(n, struct ocfs2_refcount_tree, rf_node); + + if (blkno < tree->rf_blkno) + n = n->rb_left; + else if (blkno > tree->rf_blkno) + n = n->rb_right; + else + return tree; + } + + return NULL; +} + +/* osb_lock is already locked. */ +static void ocfs2_insert_refcount_tree(struct ocfs2_super *osb, + struct ocfs2_refcount_tree *new) +{ + u64 rf_blkno = new->rf_blkno; + struct rb_node *parent = NULL; + struct rb_node **p = &osb->osb_rf_lock_tree.rb_node; + struct ocfs2_refcount_tree *tmp; + + while (*p) { + parent = *p; + + tmp = rb_entry(parent, struct ocfs2_refcount_tree, + rf_node); + + if (rf_blkno < tmp->rf_blkno) + p = &(*p)->rb_left; + else if (rf_blkno > tmp->rf_blkno) + p = &(*p)->rb_right; + else { + /* This should never happen! */ + mlog(ML_ERROR, "Duplicate refcount block %llu found!\n", + (unsigned long long)rf_blkno); + BUG(); + } + } + + rb_link_node(&new->rf_node, parent, p); + rb_insert_color(&new->rf_node, &osb->osb_rf_lock_tree); +} + +static void ocfs2_free_refcount_tree(struct ocfs2_refcount_tree *tree) +{ + ocfs2_metadata_cache_exit(&tree->rf_ci); + ocfs2_simple_drop_lockres(OCFS2_SB(tree->rf_sb), &tree->rf_lockres); + ocfs2_lock_res_free(&tree->rf_lockres); + kfree(tree); +} + +static inline void +ocfs2_erase_refcount_tree_from_list_no_lock(struct ocfs2_super *osb, + struct ocfs2_refcount_tree *tree) +{ + rb_erase(&tree->rf_node, &osb->osb_rf_lock_tree); + if (osb->osb_ref_tree_lru && osb->osb_ref_tree_lru == tree) + osb->osb_ref_tree_lru = NULL; +} + +static void ocfs2_erase_refcount_tree_from_list(struct ocfs2_super *osb, + struct ocfs2_refcount_tree *tree) +{ + spin_lock(&osb->osb_lock); + ocfs2_erase_refcount_tree_from_list_no_lock(osb, tree); + spin_unlock(&osb->osb_lock); +} + +void ocfs2_kref_remove_refcount_tree(struct kref *kref) +{ + struct ocfs2_refcount_tree *tree = + container_of(kref, struct ocfs2_refcount_tree, rf_getcnt); + + ocfs2_free_refcount_tree(tree); +} + +static inline void +ocfs2_refcount_tree_get(struct ocfs2_refcount_tree *tree) +{ + kref_get(&tree->rf_getcnt); +} + +static inline void +ocfs2_refcount_tree_put(struct ocfs2_refcount_tree *tree) +{ + kref_put(&tree->rf_getcnt, ocfs2_kref_remove_refcount_tree); +} + +static inline void ocfs2_init_refcount_tree_ci(struct ocfs2_refcount_tree *new, + struct super_block *sb) +{ + ocfs2_metadata_cache_init(&new->rf_ci, &ocfs2_refcount_caching_ops); + mutex_init(&new->rf_io_mutex); + new->rf_sb = sb; + spin_lock_init(&new->rf_lock); +} + +static inline void ocfs2_init_refcount_tree_lock(struct ocfs2_super *osb, + struct ocfs2_refcount_tree *new, + u64 rf_blkno, u32 generation) +{ + init_rwsem(&new->rf_sem); + ocfs2_refcount_lock_res_init(&new->rf_lockres, osb, + rf_blkno, generation); +} + +static struct ocfs2_refcount_tree* +ocfs2_allocate_refcount_tree(struct ocfs2_super *osb, u64 rf_blkno) +{ + struct ocfs2_refcount_tree *new; + + new = kzalloc(sizeof(struct ocfs2_refcount_tree), GFP_NOFS); + if (!new) + return NULL; + + new->rf_blkno = rf_blkno; + kref_init(&new->rf_getcnt); + ocfs2_init_refcount_tree_ci(new, osb->sb); + + return new; +} + +static int ocfs2_get_refcount_tree(struct ocfs2_super *osb, u64 rf_blkno, + struct ocfs2_refcount_tree **ret_tree) +{ + int ret = 0; + struct ocfs2_refcount_tree *tree, *new = NULL; + struct buffer_head *ref_root_bh = NULL; + struct ocfs2_refcount_block *ref_rb; + + spin_lock(&osb->osb_lock); + if (osb->osb_ref_tree_lru && + osb->osb_ref_tree_lru->rf_blkno == rf_blkno) + tree = osb->osb_ref_tree_lru; + else + tree = ocfs2_find_refcount_tree(osb, rf_blkno); + if (tree) + goto out; + + spin_unlock(&osb->osb_lock); + + new = ocfs2_allocate_refcount_tree(osb, rf_blkno); + if (!new) { + ret = -ENOMEM; + mlog_errno(ret); + return ret; + } + /* + * We need the generation to create the refcount tree lock and since + * it isn't changed during the tree modification, we are safe here to + * read without protection. + * We also have to purge the cache after we create the lock since the + * refcount block may have the stale data. It can only be trusted when + * we hold the refcount lock. + */ + ret = ocfs2_read_refcount_block(&new->rf_ci, rf_blkno, &ref_root_bh); + if (ret) { + mlog_errno(ret); + ocfs2_metadata_cache_exit(&new->rf_ci); + kfree(new); + return ret; + } + + ref_rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data; + new->rf_generation = le32_to_cpu(ref_rb->rf_generation); + ocfs2_init_refcount_tree_lock(osb, new, rf_blkno, + new->rf_generation); + ocfs2_metadata_cache_purge(&new->rf_ci); + + spin_lock(&osb->osb_lock); + tree = ocfs2_find_refcount_tree(osb, rf_blkno); + if (tree) + goto out; + + ocfs2_insert_refcount_tree(osb, new); + + tree = new; + new = NULL; + +out: + *ret_tree = tree; + + osb->osb_ref_tree_lru = tree; + + spin_unlock(&osb->osb_lock); + + if (new) + ocfs2_free_refcount_tree(new); + + brelse(ref_root_bh); + return ret; +} + +static int ocfs2_get_refcount_block(struct inode *inode, u64 *ref_blkno) +{ + int ret; + struct buffer_head *di_bh = NULL; + struct ocfs2_dinode *di; + + ret = ocfs2_read_inode_block(inode, &di_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + BUG_ON(!(OCFS2_I(inode)->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL)); + + di = (struct ocfs2_dinode *)di_bh->b_data; + *ref_blkno = le64_to_cpu(di->i_refcount_loc); + brelse(di_bh); +out: + return ret; +} + +static int __ocfs2_lock_refcount_tree(struct ocfs2_super *osb, + struct ocfs2_refcount_tree *tree, int rw) +{ + int ret; + + ret = ocfs2_refcount_lock(tree, rw); + if (ret) { + mlog_errno(ret); + goto out; + } + + if (rw) + down_write(&tree->rf_sem); + else + down_read(&tree->rf_sem); + +out: + return ret; +} + +/* + * Lock the refcount tree pointed by ref_blkno and return the tree. + * In most case, we lock the tree and read the refcount block. + * So read it here if the caller really needs it. + * + * If the tree has been re-created by other node, it will free the + * old one and re-create it. + */ +int ocfs2_lock_refcount_tree(struct ocfs2_super *osb, + u64 ref_blkno, int rw, + struct ocfs2_refcount_tree **ret_tree, + struct buffer_head **ref_bh) +{ + int ret, delete_tree = 0; + struct ocfs2_refcount_tree *tree = NULL; + struct buffer_head *ref_root_bh = NULL; + struct ocfs2_refcount_block *rb; + +again: + ret = ocfs2_get_refcount_tree(osb, ref_blkno, &tree); + if (ret) { + mlog_errno(ret); + return ret; + } + + ocfs2_refcount_tree_get(tree); + + ret = __ocfs2_lock_refcount_tree(osb, tree, rw); + if (ret) { + mlog_errno(ret); + ocfs2_refcount_tree_put(tree); + goto out; + } + + ret = ocfs2_read_refcount_block(&tree->rf_ci, tree->rf_blkno, + &ref_root_bh); + if (ret) { + mlog_errno(ret); + ocfs2_unlock_refcount_tree(osb, tree, rw); + ocfs2_refcount_tree_put(tree); + goto out; + } + + rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data; + /* + * If the refcount block has been freed and re-created, we may need + * to recreate the refcount tree also. + * + * Here we just remove the tree from the rb-tree, and the last + * kref holder will unlock and delete this refcount_tree. + * Then we goto "again" and ocfs2_get_refcount_tree will create + * the new refcount tree for us. + */ + if (tree->rf_generation != le32_to_cpu(rb->rf_generation)) { + if (!tree->rf_removed) { + ocfs2_erase_refcount_tree_from_list(osb, tree); + tree->rf_removed = 1; + delete_tree = 1; + } + + ocfs2_unlock_refcount_tree(osb, tree, rw); + /* + * We get an extra reference when we create the refcount + * tree, so another put will destroy it. + */ + if (delete_tree) + ocfs2_refcount_tree_put(tree); + brelse(ref_root_bh); + ref_root_bh = NULL; + goto again; + } + + *ret_tree = tree; + if (ref_bh) { + *ref_bh = ref_root_bh; + ref_root_bh = NULL; + } +out: + brelse(ref_root_bh); + return ret; +} + +int ocfs2_lock_refcount_tree_by_inode(struct inode *inode, int rw, + struct ocfs2_refcount_tree **ret_tree, + struct buffer_head **ref_bh) +{ + int ret; + u64 ref_blkno; + + ret = ocfs2_get_refcount_block(inode, &ref_blkno); + if (ret) { + mlog_errno(ret); + return ret; + } + + return ocfs2_lock_refcount_tree(OCFS2_SB(inode->i_sb), ref_blkno, + rw, ret_tree, ref_bh); +} + +void ocfs2_unlock_refcount_tree(struct ocfs2_super *osb, + struct ocfs2_refcount_tree *tree, int rw) +{ + if (rw) + up_write(&tree->rf_sem); + else + up_read(&tree->rf_sem); + + ocfs2_refcount_unlock(tree, rw); + ocfs2_refcount_tree_put(tree); +} + +void ocfs2_purge_refcount_trees(struct ocfs2_super *osb) +{ + struct rb_node *node; + struct ocfs2_refcount_tree *tree; + struct rb_root *root = &osb->osb_rf_lock_tree; + + while ((node = rb_last(root)) != NULL) { + tree = rb_entry(node, struct ocfs2_refcount_tree, rf_node); + + mlog(0, "Purge tree %llu\n", + (unsigned long long) tree->rf_blkno); + + rb_erase(&tree->rf_node, root); + ocfs2_free_refcount_tree(tree); + } +} + +/* + * Create a refcount tree for an inode. + * We take for granted that the inode is already locked. + */ +static int ocfs2_create_refcount_tree(struct inode *inode, + struct buffer_head *di_bh) +{ + int ret; + handle_t *handle = NULL; + struct ocfs2_alloc_context *meta_ac = NULL; + struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data; + struct ocfs2_inode_info *oi = OCFS2_I(inode); + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + struct buffer_head *new_bh = NULL; + struct ocfs2_refcount_block *rb; + struct ocfs2_refcount_tree *new_tree = NULL, *tree = NULL; + u16 suballoc_bit_start; + u32 num_got; + u64 first_blkno; + + BUG_ON(oi->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL); + + mlog(0, "create tree for inode %lu\n", inode->i_ino); + + ret = ocfs2_reserve_new_metadata_blocks(osb, 1, &meta_ac); + if (ret) { + mlog_errno(ret); + goto out; + } + + handle = ocfs2_start_trans(osb, OCFS2_REFCOUNT_TREE_CREATE_CREDITS); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto out; + } + + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + + ret = ocfs2_claim_metadata(osb, handle, meta_ac, 1, + &suballoc_bit_start, &num_got, + &first_blkno); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + + new_tree = ocfs2_allocate_refcount_tree(osb, first_blkno); + if (!new_tree) { + ret = -ENOMEM; + mlog_errno(ret); + goto out_commit; + } + + new_bh = sb_getblk(inode->i_sb, first_blkno); + ocfs2_set_new_buffer_uptodate(&new_tree->rf_ci, new_bh); + + ret = ocfs2_journal_access_rb(handle, &new_tree->rf_ci, new_bh, + OCFS2_JOURNAL_ACCESS_CREATE); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + + /* Initialize ocfs2_refcount_block. */ + rb = (struct ocfs2_refcount_block *)new_bh->b_data; + memset(rb, 0, inode->i_sb->s_blocksize); + strcpy((void *)rb, OCFS2_REFCOUNT_BLOCK_SIGNATURE); + rb->rf_suballoc_slot = cpu_to_le16(osb->slot_num); + rb->rf_suballoc_bit = cpu_to_le16(suballoc_bit_start); + rb->rf_fs_generation = cpu_to_le32(osb->fs_generation); + rb->rf_blkno = cpu_to_le64(first_blkno); + rb->rf_count = cpu_to_le32(1); + rb->rf_records.rl_count = + cpu_to_le16(ocfs2_refcount_recs_per_rb(osb->sb)); + spin_lock(&osb->osb_lock); + rb->rf_generation = osb->s_next_generation++; + spin_unlock(&osb->osb_lock); + + ocfs2_journal_dirty(handle, new_bh); + + spin_lock(&oi->ip_lock); + oi->ip_dyn_features |= OCFS2_HAS_REFCOUNT_FL; + di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features); + di->i_refcount_loc = cpu_to_le64(first_blkno); + spin_unlock(&oi->ip_lock); + + mlog(0, "created tree for inode %lu, refblock %llu\n", + inode->i_ino, (unsigned long long)first_blkno); + + ocfs2_journal_dirty(handle, di_bh); + + /* + * We have to init the tree lock here since it will use + * the generation number to create it. + */ + new_tree->rf_generation = le32_to_cpu(rb->rf_generation); + ocfs2_init_refcount_tree_lock(osb, new_tree, first_blkno, + new_tree->rf_generation); + + spin_lock(&osb->osb_lock); + tree = ocfs2_find_refcount_tree(osb, first_blkno); + + /* + * We've just created a new refcount tree in this block. If + * we found a refcount tree on the ocfs2_super, it must be + * one we just deleted. We free the old tree before + * inserting the new tree. + */ + BUG_ON(tree && tree->rf_generation == new_tree->rf_generation); + if (tree) + ocfs2_erase_refcount_tree_from_list_no_lock(osb, tree); + ocfs2_insert_refcount_tree(osb, new_tree); + spin_unlock(&osb->osb_lock); + new_tree = NULL; + if (tree) + ocfs2_refcount_tree_put(tree); + +out_commit: + ocfs2_commit_trans(osb, handle); + +out: + if (new_tree) { + ocfs2_metadata_cache_exit(&new_tree->rf_ci); + kfree(new_tree); + } + + brelse(new_bh); + if (meta_ac) + ocfs2_free_alloc_context(meta_ac); + + return ret; +} + +static int ocfs2_set_refcount_tree(struct inode *inode, + struct buffer_head *di_bh, + u64 refcount_loc) +{ + int ret; + handle_t *handle = NULL; + struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data; + struct ocfs2_inode_info *oi = OCFS2_I(inode); + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + struct buffer_head *ref_root_bh = NULL; + struct ocfs2_refcount_block *rb; + struct ocfs2_refcount_tree *ref_tree; + + BUG_ON(oi->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL); + + ret = ocfs2_lock_refcount_tree(osb, refcount_loc, 1, + &ref_tree, &ref_root_bh); + if (ret) { + mlog_errno(ret); + return ret; + } + + handle = ocfs2_start_trans(osb, OCFS2_REFCOUNT_TREE_SET_CREDITS); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto out; + } + + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + + ret = ocfs2_journal_access_rb(handle, &ref_tree->rf_ci, ref_root_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + + rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data; + le32_add_cpu(&rb->rf_count, 1); + + ocfs2_journal_dirty(handle, ref_root_bh); + + spin_lock(&oi->ip_lock); + oi->ip_dyn_features |= OCFS2_HAS_REFCOUNT_FL; + di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features); + di->i_refcount_loc = cpu_to_le64(refcount_loc); + spin_unlock(&oi->ip_lock); + ocfs2_journal_dirty(handle, di_bh); + +out_commit: + ocfs2_commit_trans(osb, handle); +out: + ocfs2_unlock_refcount_tree(osb, ref_tree, 1); + brelse(ref_root_bh); + + return ret; +} + +int ocfs2_remove_refcount_tree(struct inode *inode, struct buffer_head *di_bh) +{ + int ret, delete_tree = 0; + handle_t *handle = NULL; + struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data; + struct ocfs2_inode_info *oi = OCFS2_I(inode); + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + struct ocfs2_refcount_block *rb; + struct inode *alloc_inode = NULL; + struct buffer_head *alloc_bh = NULL; + struct buffer_head *blk_bh = NULL; + struct ocfs2_refcount_tree *ref_tree; + int credits = OCFS2_REFCOUNT_TREE_REMOVE_CREDITS; + u64 blk = 0, bg_blkno = 0, ref_blkno = le64_to_cpu(di->i_refcount_loc); + u16 bit = 0; + + if (!(oi->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL)) + return 0; + + BUG_ON(!ref_blkno); + ret = ocfs2_lock_refcount_tree(osb, ref_blkno, 1, &ref_tree, &blk_bh); + if (ret) { + mlog_errno(ret); + return ret; + } + + rb = (struct ocfs2_refcount_block *)blk_bh->b_data; + + /* + * If we are the last user, we need to free the block. + * So lock the allocator ahead. + */ + if (le32_to_cpu(rb->rf_count) == 1) { + blk = le64_to_cpu(rb->rf_blkno); + bit = le16_to_cpu(rb->rf_suballoc_bit); + bg_blkno = ocfs2_which_suballoc_group(blk, bit); + + alloc_inode = ocfs2_get_system_file_inode(osb, + EXTENT_ALLOC_SYSTEM_INODE, + le16_to_cpu(rb->rf_suballoc_slot)); + if (!alloc_inode) { + ret = -ENOMEM; + mlog_errno(ret); + goto out; + } + mutex_lock(&alloc_inode->i_mutex); + + ret = ocfs2_inode_lock(alloc_inode, &alloc_bh, 1); + if (ret) { + mlog_errno(ret); + goto out_mutex; + } + + credits += OCFS2_SUBALLOC_FREE; + } + + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto out_unlock; + } + + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + + ret = ocfs2_journal_access_rb(handle, &ref_tree->rf_ci, blk_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + + spin_lock(&oi->ip_lock); + oi->ip_dyn_features &= ~OCFS2_HAS_REFCOUNT_FL; + di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features); + di->i_refcount_loc = 0; + spin_unlock(&oi->ip_lock); + ocfs2_journal_dirty(handle, di_bh); + + le32_add_cpu(&rb->rf_count , -1); + ocfs2_journal_dirty(handle, blk_bh); + + if (!rb->rf_count) { + delete_tree = 1; + ocfs2_erase_refcount_tree_from_list(osb, ref_tree); + ret = ocfs2_free_suballoc_bits(handle, alloc_inode, + alloc_bh, bit, bg_blkno, 1); + if (ret) + mlog_errno(ret); + } + +out_commit: + ocfs2_commit_trans(osb, handle); +out_unlock: + if (alloc_inode) { + ocfs2_inode_unlock(alloc_inode, 1); + brelse(alloc_bh); + } +out_mutex: + if (alloc_inode) { + mutex_unlock(&alloc_inode->i_mutex); + iput(alloc_inode); + } +out: + ocfs2_unlock_refcount_tree(osb, ref_tree, 1); + if (delete_tree) + ocfs2_refcount_tree_put(ref_tree); + brelse(blk_bh); + + return ret; +} + +static void ocfs2_find_refcount_rec_in_rl(struct ocfs2_caching_info *ci, + struct buffer_head *ref_leaf_bh, + u64 cpos, unsigned int len, + struct ocfs2_refcount_rec *ret_rec, + int *index) +{ + int i = 0; + struct ocfs2_refcount_block *rb = + (struct ocfs2_refcount_block *)ref_leaf_bh->b_data; + struct ocfs2_refcount_rec *rec = NULL; + + for (; i < le16_to_cpu(rb->rf_records.rl_used); i++) { + rec = &rb->rf_records.rl_recs[i]; + + if (le64_to_cpu(rec->r_cpos) + + le32_to_cpu(rec->r_clusters) <= cpos) + continue; + else if (le64_to_cpu(rec->r_cpos) > cpos) + break; + + /* ok, cpos fail in this rec. Just return. */ + if (ret_rec) + *ret_rec = *rec; + goto out; + } + + if (ret_rec) { + /* We meet with a hole here, so fake the rec. */ + ret_rec->r_cpos = cpu_to_le64(cpos); + ret_rec->r_refcount = 0; + if (i < le16_to_cpu(rb->rf_records.rl_used) && + le64_to_cpu(rec->r_cpos) < cpos + len) + ret_rec->r_clusters = + cpu_to_le32(le64_to_cpu(rec->r_cpos) - cpos); + else + ret_rec->r_clusters = cpu_to_le32(len); + } + +out: + *index = i; +} + +/* + * Try to remove refcount tree. The mechanism is: + * 1) Check whether i_clusters == 0, if no, exit. + * 2) check whether we have i_xattr_loc in dinode. if yes, exit. + * 3) Check whether we have inline xattr stored outside, if yes, exit. + * 4) Remove the tree. + */ +int ocfs2_try_remove_refcount_tree(struct inode *inode, + struct buffer_head *di_bh) +{ + int ret; + struct ocfs2_inode_info *oi = OCFS2_I(inode); + struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data; + + down_write(&oi->ip_xattr_sem); + down_write(&oi->ip_alloc_sem); + + if (oi->ip_clusters) + goto out; + + if ((oi->ip_dyn_features & OCFS2_HAS_XATTR_FL) && di->i_xattr_loc) + goto out; + + if (oi->ip_dyn_features & OCFS2_INLINE_XATTR_FL && + ocfs2_has_inline_xattr_value_outside(inode, di)) + goto out; + + ret = ocfs2_remove_refcount_tree(inode, di_bh); + if (ret) + mlog_errno(ret); +out: + up_write(&oi->ip_alloc_sem); + up_write(&oi->ip_xattr_sem); + return 0; +} + +/* + * Given a cpos and len, try to find the refcount record which contains cpos. + * 1. If cpos can be found in one refcount record, return the record. + * 2. If cpos can't be found, return a fake record which start from cpos + * and end at a small value between cpos+len and start of the next record. + * This fake record has r_refcount = 0. + */ +static int ocfs2_get_refcount_rec(struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + u64 cpos, unsigned int len, + struct ocfs2_refcount_rec *ret_rec, + int *index, + struct buffer_head **ret_bh) +{ + int ret = 0, i, found; + u32 low_cpos; + struct ocfs2_extent_list *el; + struct ocfs2_extent_rec *tmp, *rec = NULL; + struct ocfs2_extent_block *eb; + struct buffer_head *eb_bh = NULL, *ref_leaf_bh = NULL; + struct super_block *sb = ocfs2_metadata_cache_get_super(ci); + struct ocfs2_refcount_block *rb = + (struct ocfs2_refcount_block *)ref_root_bh->b_data; + + if (!(le32_to_cpu(rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL)) { + ocfs2_find_refcount_rec_in_rl(ci, ref_root_bh, cpos, len, + ret_rec, index); + *ret_bh = ref_root_bh; + get_bh(ref_root_bh); + return 0; + } + + el = &rb->rf_list; + low_cpos = cpos & OCFS2_32BIT_POS_MASK; + + if (el->l_tree_depth) { + ret = ocfs2_find_leaf(ci, el, low_cpos, &eb_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + eb = (struct ocfs2_extent_block *) eb_bh->b_data; + el = &eb->h_list; + + if (el->l_tree_depth) { + ocfs2_error(sb, + "refcount tree %llu has non zero tree " + "depth in leaf btree tree block %llu\n", + (unsigned long long)ocfs2_metadata_cache_owner(ci), + (unsigned long long)eb_bh->b_blocknr); + ret = -EROFS; + goto out; + } + } + + found = 0; + for (i = le16_to_cpu(el->l_next_free_rec) - 1; i >= 0; i--) { + rec = &el->l_recs[i]; + + if (le32_to_cpu(rec->e_cpos) <= low_cpos) { + found = 1; + break; + } + } + + /* adjust len when we have ocfs2_extent_rec after it. */ + if (found && i < le16_to_cpu(el->l_next_free_rec) - 1) { + tmp = &el->l_recs[i+1]; + + if (le32_to_cpu(tmp->e_cpos) < cpos + len) + len = le32_to_cpu(tmp->e_cpos) - cpos; + } + + ret = ocfs2_read_refcount_block(ci, le64_to_cpu(rec->e_blkno), + &ref_leaf_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + ocfs2_find_refcount_rec_in_rl(ci, ref_leaf_bh, cpos, len, + ret_rec, index); + *ret_bh = ref_leaf_bh; +out: + brelse(eb_bh); + return ret; +} + +enum ocfs2_ref_rec_contig { + REF_CONTIG_NONE = 0, + REF_CONTIG_LEFT, + REF_CONTIG_RIGHT, + REF_CONTIG_LEFTRIGHT, +}; + +static enum ocfs2_ref_rec_contig + ocfs2_refcount_rec_adjacent(struct ocfs2_refcount_block *rb, + int index) +{ + if ((rb->rf_records.rl_recs[index].r_refcount == + rb->rf_records.rl_recs[index + 1].r_refcount) && + (le64_to_cpu(rb->rf_records.rl_recs[index].r_cpos) + + le32_to_cpu(rb->rf_records.rl_recs[index].r_clusters) == + le64_to_cpu(rb->rf_records.rl_recs[index + 1].r_cpos))) + return REF_CONTIG_RIGHT; + + return REF_CONTIG_NONE; +} + +static enum ocfs2_ref_rec_contig + ocfs2_refcount_rec_contig(struct ocfs2_refcount_block *rb, + int index) +{ + enum ocfs2_ref_rec_contig ret = REF_CONTIG_NONE; + + if (index < le16_to_cpu(rb->rf_records.rl_used) - 1) + ret = ocfs2_refcount_rec_adjacent(rb, index); + + if (index > 0) { + enum ocfs2_ref_rec_contig tmp; + + tmp = ocfs2_refcount_rec_adjacent(rb, index - 1); + + if (tmp == REF_CONTIG_RIGHT) { + if (ret == REF_CONTIG_RIGHT) + ret = REF_CONTIG_LEFTRIGHT; + else + ret = REF_CONTIG_LEFT; + } + } + + return ret; +} + +static void ocfs2_rotate_refcount_rec_left(struct ocfs2_refcount_block *rb, + int index) +{ + BUG_ON(rb->rf_records.rl_recs[index].r_refcount != + rb->rf_records.rl_recs[index+1].r_refcount); + + le32_add_cpu(&rb->rf_records.rl_recs[index].r_clusters, + le32_to_cpu(rb->rf_records.rl_recs[index+1].r_clusters)); + + if (index < le16_to_cpu(rb->rf_records.rl_used) - 2) + memmove(&rb->rf_records.rl_recs[index + 1], + &rb->rf_records.rl_recs[index + 2], + sizeof(struct ocfs2_refcount_rec) * + (le16_to_cpu(rb->rf_records.rl_used) - index - 2)); + + memset(&rb->rf_records.rl_recs[le16_to_cpu(rb->rf_records.rl_used) - 1], + 0, sizeof(struct ocfs2_refcount_rec)); + le16_add_cpu(&rb->rf_records.rl_used, -1); +} + +/* + * Merge the refcount rec if we are contiguous with the adjacent recs. + */ +static void ocfs2_refcount_rec_merge(struct ocfs2_refcount_block *rb, + int index) +{ + enum ocfs2_ref_rec_contig contig = + ocfs2_refcount_rec_contig(rb, index); + + if (contig == REF_CONTIG_NONE) + return; + + if (contig == REF_CONTIG_LEFT || contig == REF_CONTIG_LEFTRIGHT) { + BUG_ON(index == 0); + index--; + } + + ocfs2_rotate_refcount_rec_left(rb, index); + + if (contig == REF_CONTIG_LEFTRIGHT) + ocfs2_rotate_refcount_rec_left(rb, index); +} + +/* + * Change the refcount indexed by "index" in ref_bh. + * If refcount reaches 0, remove it. + */ +static int ocfs2_change_refcount_rec(handle_t *handle, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_leaf_bh, + int index, int merge, int change) +{ + int ret; + struct ocfs2_refcount_block *rb = + (struct ocfs2_refcount_block *)ref_leaf_bh->b_data; + struct ocfs2_refcount_list *rl = &rb->rf_records; + struct ocfs2_refcount_rec *rec = &rl->rl_recs[index]; + + ret = ocfs2_journal_access_rb(handle, ci, ref_leaf_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto out; + } + + mlog(0, "change index %d, old count %u, change %d\n", index, + le32_to_cpu(rec->r_refcount), change); + le32_add_cpu(&rec->r_refcount, change); + + if (!rec->r_refcount) { + if (index != le16_to_cpu(rl->rl_used) - 1) { + memmove(rec, rec + 1, + (le16_to_cpu(rl->rl_used) - index - 1) * + sizeof(struct ocfs2_refcount_rec)); + memset(&rl->rl_recs[le16_to_cpu(rl->rl_used) - 1], + 0, sizeof(struct ocfs2_refcount_rec)); + } + + le16_add_cpu(&rl->rl_used, -1); + } else if (merge) + ocfs2_refcount_rec_merge(rb, index); + + ret = ocfs2_journal_dirty(handle, ref_leaf_bh); + if (ret) + mlog_errno(ret); +out: + return ret; +} + +static int ocfs2_expand_inline_ref_root(handle_t *handle, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + struct buffer_head **ref_leaf_bh, + struct ocfs2_alloc_context *meta_ac) +{ + int ret; + u16 suballoc_bit_start; + u32 num_got; + u64 blkno; + struct super_block *sb = ocfs2_metadata_cache_get_super(ci); + struct buffer_head *new_bh = NULL; + struct ocfs2_refcount_block *new_rb; + struct ocfs2_refcount_block *root_rb = + (struct ocfs2_refcount_block *)ref_root_bh->b_data; + + ret = ocfs2_journal_access_rb(handle, ci, ref_root_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_claim_metadata(OCFS2_SB(sb), handle, meta_ac, 1, + &suballoc_bit_start, &num_got, + &blkno); + if (ret) { + mlog_errno(ret); + goto out; + } + + new_bh = sb_getblk(sb, blkno); + if (new_bh == NULL) { + ret = -EIO; + mlog_errno(ret); + goto out; + } + ocfs2_set_new_buffer_uptodate(ci, new_bh); + + ret = ocfs2_journal_access_rb(handle, ci, new_bh, + OCFS2_JOURNAL_ACCESS_CREATE); + if (ret) { + mlog_errno(ret); + goto out; + } + + /* + * Initialize ocfs2_refcount_block. + * It should contain the same information as the old root. + * so just memcpy it and change the corresponding field. + */ + memcpy(new_bh->b_data, ref_root_bh->b_data, sb->s_blocksize); + + new_rb = (struct ocfs2_refcount_block *)new_bh->b_data; + new_rb->rf_suballoc_slot = cpu_to_le16(OCFS2_SB(sb)->slot_num); + new_rb->rf_suballoc_bit = cpu_to_le16(suballoc_bit_start); + new_rb->rf_blkno = cpu_to_le64(blkno); + new_rb->rf_cpos = cpu_to_le32(0); + new_rb->rf_parent = cpu_to_le64(ref_root_bh->b_blocknr); + new_rb->rf_flags = cpu_to_le32(OCFS2_REFCOUNT_LEAF_FL); + ocfs2_journal_dirty(handle, new_bh); + + /* Now change the root. */ + memset(&root_rb->rf_list, 0, sb->s_blocksize - + offsetof(struct ocfs2_refcount_block, rf_list)); + root_rb->rf_list.l_count = cpu_to_le16(ocfs2_extent_recs_per_rb(sb)); + root_rb->rf_clusters = cpu_to_le32(1); + root_rb->rf_list.l_next_free_rec = cpu_to_le16(1); + root_rb->rf_list.l_recs[0].e_blkno = cpu_to_le64(blkno); + root_rb->rf_list.l_recs[0].e_leaf_clusters = cpu_to_le16(1); + root_rb->rf_flags = cpu_to_le32(OCFS2_REFCOUNT_TREE_FL); + + ocfs2_journal_dirty(handle, ref_root_bh); + + mlog(0, "new leaf block %llu, used %u\n", (unsigned long long)blkno, + le16_to_cpu(new_rb->rf_records.rl_used)); + + *ref_leaf_bh = new_bh; + new_bh = NULL; +out: + brelse(new_bh); + return ret; +} + +static int ocfs2_refcount_rec_no_intersect(struct ocfs2_refcount_rec *prev, + struct ocfs2_refcount_rec *next) +{ + if (ocfs2_get_ref_rec_low_cpos(prev) + le32_to_cpu(prev->r_clusters) <= + ocfs2_get_ref_rec_low_cpos(next)) + return 1; + + return 0; +} + +static int cmp_refcount_rec_by_low_cpos(const void *a, const void *b) +{ + const struct ocfs2_refcount_rec *l = a, *r = b; + u32 l_cpos = ocfs2_get_ref_rec_low_cpos(l); + u32 r_cpos = ocfs2_get_ref_rec_low_cpos(r); + + if (l_cpos > r_cpos) + return 1; + if (l_cpos < r_cpos) + return -1; + return 0; +} + +static int cmp_refcount_rec_by_cpos(const void *a, const void *b) +{ + const struct ocfs2_refcount_rec *l = a, *r = b; + u64 l_cpos = le64_to_cpu(l->r_cpos); + u64 r_cpos = le64_to_cpu(r->r_cpos); + + if (l_cpos > r_cpos) + return 1; + if (l_cpos < r_cpos) + return -1; + return 0; +} + +static void swap_refcount_rec(void *a, void *b, int size) +{ + struct ocfs2_refcount_rec *l = a, *r = b, tmp; + + tmp = *(struct ocfs2_refcount_rec *)l; + *(struct ocfs2_refcount_rec *)l = + *(struct ocfs2_refcount_rec *)r; + *(struct ocfs2_refcount_rec *)r = tmp; +} + +/* + * The refcount cpos are ordered by their 64bit cpos, + * But we will use the low 32 bit to be the e_cpos in the b-tree. + * So we need to make sure that this pos isn't intersected with others. + * + * Note: The refcount block is already sorted by their low 32 bit cpos, + * So just try the middle pos first, and we will exit when we find + * the good position. + */ +static int ocfs2_find_refcount_split_pos(struct ocfs2_refcount_list *rl, + u32 *split_pos, int *split_index) +{ + int num_used = le16_to_cpu(rl->rl_used); + int delta, middle = num_used / 2; + + for (delta = 0; delta < middle; delta++) { + /* Let's check delta earlier than middle */ + if (ocfs2_refcount_rec_no_intersect( + &rl->rl_recs[middle - delta - 1], + &rl->rl_recs[middle - delta])) { + *split_index = middle - delta; + break; + } + + /* For even counts, don't walk off the end */ + if ((middle + delta + 1) == num_used) + continue; + + /* Now try delta past middle */ + if (ocfs2_refcount_rec_no_intersect( + &rl->rl_recs[middle + delta], + &rl->rl_recs[middle + delta + 1])) { + *split_index = middle + delta + 1; + break; + } + } + + if (delta >= middle) + return -ENOSPC; + + *split_pos = ocfs2_get_ref_rec_low_cpos(&rl->rl_recs[*split_index]); + return 0; +} + +static int ocfs2_divide_leaf_refcount_block(struct buffer_head *ref_leaf_bh, + struct buffer_head *new_bh, + u32 *split_cpos) +{ + int split_index = 0, num_moved, ret; + u32 cpos = 0; + struct ocfs2_refcount_block *rb = + (struct ocfs2_refcount_block *)ref_leaf_bh->b_data; + struct ocfs2_refcount_list *rl = &rb->rf_records; + struct ocfs2_refcount_block *new_rb = + (struct ocfs2_refcount_block *)new_bh->b_data; + struct ocfs2_refcount_list *new_rl = &new_rb->rf_records; + + mlog(0, "split old leaf refcount block %llu, count = %u, used = %u\n", + (unsigned long long)ref_leaf_bh->b_blocknr, + le32_to_cpu(rl->rl_count), le32_to_cpu(rl->rl_used)); + + /* + * XXX: Improvement later. + * If we know all the high 32 bit cpos is the same, no need to sort. + * + * In order to make the whole process safe, we do: + * 1. sort the entries by their low 32 bit cpos first so that we can + * find the split cpos easily. + * 2. call ocfs2_insert_extent to insert the new refcount block. + * 3. move the refcount rec to the new block. + * 4. sort the entries by their 64 bit cpos. + * 5. dirty the new_rb and rb. + */ + sort(&rl->rl_recs, le16_to_cpu(rl->rl_used), + sizeof(struct ocfs2_refcount_rec), + cmp_refcount_rec_by_low_cpos, swap_refcount_rec); + + ret = ocfs2_find_refcount_split_pos(rl, &cpos, &split_index); + if (ret) { + mlog_errno(ret); + return ret; + } + + new_rb->rf_cpos = cpu_to_le32(cpos); + + /* move refcount records starting from split_index to the new block. */ + num_moved = le16_to_cpu(rl->rl_used) - split_index; + memcpy(new_rl->rl_recs, &rl->rl_recs[split_index], + num_moved * sizeof(struct ocfs2_refcount_rec)); + + /*ok, remove the entries we just moved over to the other block. */ + memset(&rl->rl_recs[split_index], 0, + num_moved * sizeof(struct ocfs2_refcount_rec)); + + /* change old and new rl_used accordingly. */ + le16_add_cpu(&rl->rl_used, -num_moved); + new_rl->rl_used = cpu_to_le32(num_moved); + + sort(&rl->rl_recs, le16_to_cpu(rl->rl_used), + sizeof(struct ocfs2_refcount_rec), + cmp_refcount_rec_by_cpos, swap_refcount_rec); + + sort(&new_rl->rl_recs, le16_to_cpu(new_rl->rl_used), + sizeof(struct ocfs2_refcount_rec), + cmp_refcount_rec_by_cpos, swap_refcount_rec); + + *split_cpos = cpos; + return 0; +} + +static int ocfs2_new_leaf_refcount_block(handle_t *handle, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + struct buffer_head *ref_leaf_bh, + struct ocfs2_alloc_context *meta_ac) +{ + int ret; + u16 suballoc_bit_start; + u32 num_got, new_cpos; + u64 blkno; + struct super_block *sb = ocfs2_metadata_cache_get_super(ci); + struct ocfs2_refcount_block *root_rb = + (struct ocfs2_refcount_block *)ref_root_bh->b_data; + struct buffer_head *new_bh = NULL; + struct ocfs2_refcount_block *new_rb; + struct ocfs2_extent_tree ref_et; + + BUG_ON(!(le32_to_cpu(root_rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL)); + + ret = ocfs2_journal_access_rb(handle, ci, ref_root_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_journal_access_rb(handle, ci, ref_leaf_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_claim_metadata(OCFS2_SB(sb), handle, meta_ac, 1, + &suballoc_bit_start, &num_got, + &blkno); + if (ret) { + mlog_errno(ret); + goto out; + } + + new_bh = sb_getblk(sb, blkno); + if (new_bh == NULL) { + ret = -EIO; + mlog_errno(ret); + goto out; + } + ocfs2_set_new_buffer_uptodate(ci, new_bh); + + ret = ocfs2_journal_access_rb(handle, ci, new_bh, + OCFS2_JOURNAL_ACCESS_CREATE); + if (ret) { + mlog_errno(ret); + goto out; + } + + /* Initialize ocfs2_refcount_block. */ + new_rb = (struct ocfs2_refcount_block *)new_bh->b_data; + memset(new_rb, 0, sb->s_blocksize); + strcpy((void *)new_rb, OCFS2_REFCOUNT_BLOCK_SIGNATURE); + new_rb->rf_suballoc_slot = cpu_to_le16(OCFS2_SB(sb)->slot_num); + new_rb->rf_suballoc_bit = cpu_to_le16(suballoc_bit_start); + new_rb->rf_fs_generation = cpu_to_le32(OCFS2_SB(sb)->fs_generation); + new_rb->rf_blkno = cpu_to_le64(blkno); + new_rb->rf_parent = cpu_to_le64(ref_root_bh->b_blocknr); + new_rb->rf_flags = cpu_to_le32(OCFS2_REFCOUNT_LEAF_FL); + new_rb->rf_records.rl_count = + cpu_to_le16(ocfs2_refcount_recs_per_rb(sb)); + new_rb->rf_generation = root_rb->rf_generation; + + ret = ocfs2_divide_leaf_refcount_block(ref_leaf_bh, new_bh, &new_cpos); + if (ret) { + mlog_errno(ret); + goto out; + } + + ocfs2_journal_dirty(handle, ref_leaf_bh); + ocfs2_journal_dirty(handle, new_bh); + + ocfs2_init_refcount_extent_tree(&ref_et, ci, ref_root_bh); + + mlog(0, "insert new leaf block %llu at %u\n", + (unsigned long long)new_bh->b_blocknr, new_cpos); + + /* Insert the new leaf block with the specific offset cpos. */ + ret = ocfs2_insert_extent(handle, &ref_et, new_cpos, new_bh->b_blocknr, + 1, 0, meta_ac); + if (ret) + mlog_errno(ret); + +out: + brelse(new_bh); + return ret; +} + +static int ocfs2_expand_refcount_tree(handle_t *handle, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + struct buffer_head *ref_leaf_bh, + struct ocfs2_alloc_context *meta_ac) +{ + int ret; + struct buffer_head *expand_bh = NULL; + + if (ref_root_bh == ref_leaf_bh) { + /* + * the old root bh hasn't been expanded to a b-tree, + * so expand it first. + */ + ret = ocfs2_expand_inline_ref_root(handle, ci, ref_root_bh, + &expand_bh, meta_ac); + if (ret) { + mlog_errno(ret); + goto out; + } + } else { + expand_bh = ref_leaf_bh; + get_bh(expand_bh); + } + + + /* Now add a new refcount block into the tree.*/ + ret = ocfs2_new_leaf_refcount_block(handle, ci, ref_root_bh, + expand_bh, meta_ac); + if (ret) + mlog_errno(ret); +out: + brelse(expand_bh); + return ret; +} + +/* + * Adjust the extent rec in b-tree representing ref_leaf_bh. + * + * Only called when we have inserted a new refcount rec at index 0 + * which means ocfs2_extent_rec.e_cpos may need some change. + */ +static int ocfs2_adjust_refcount_rec(handle_t *handle, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + struct buffer_head *ref_leaf_bh, + struct ocfs2_refcount_rec *rec) +{ + int ret = 0, i; + u32 new_cpos, old_cpos; + struct ocfs2_path *path = NULL; + struct ocfs2_extent_tree et; + struct ocfs2_refcount_block *rb = + (struct ocfs2_refcount_block *)ref_root_bh->b_data; + struct ocfs2_extent_list *el; + + if (!(le32_to_cpu(rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL)) + goto out; + + rb = (struct ocfs2_refcount_block *)ref_leaf_bh->b_data; + old_cpos = le32_to_cpu(rb->rf_cpos); + new_cpos = le64_to_cpu(rec->r_cpos) & OCFS2_32BIT_POS_MASK; + if (old_cpos <= new_cpos) + goto out; + + ocfs2_init_refcount_extent_tree(&et, ci, ref_root_bh); + + path = ocfs2_new_path_from_et(&et); + if (!path) { + ret = -ENOMEM; + mlog_errno(ret); + goto out; + } + + ret = ocfs2_find_path(ci, path, old_cpos); + if (ret) { + mlog_errno(ret); + goto out; + } + + /* + * 2 more credits, one for the leaf refcount block, one for + * the extent block contains the extent rec. + */ + ret = ocfs2_extend_trans(handle, handle->h_buffer_credits + 2); + if (ret < 0) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_journal_access_rb(handle, ci, ref_leaf_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret < 0) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_journal_access_eb(handle, ci, path_leaf_bh(path), + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret < 0) { + mlog_errno(ret); + goto out; + } + + /* change the leaf extent block first. */ + el = path_leaf_el(path); + + for (i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) + if (le32_to_cpu(el->l_recs[i].e_cpos) == old_cpos) + break; + + BUG_ON(i == le16_to_cpu(el->l_next_free_rec)); + + el->l_recs[i].e_cpos = cpu_to_le32(new_cpos); + + /* change the r_cpos in the leaf block. */ + rb->rf_cpos = cpu_to_le32(new_cpos); + + ocfs2_journal_dirty(handle, path_leaf_bh(path)); + ocfs2_journal_dirty(handle, ref_leaf_bh); + +out: + ocfs2_free_path(path); + return ret; +} + +static int ocfs2_insert_refcount_rec(handle_t *handle, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + struct buffer_head *ref_leaf_bh, + struct ocfs2_refcount_rec *rec, + int index, int merge, + struct ocfs2_alloc_context *meta_ac) +{ + int ret; + struct ocfs2_refcount_block *rb = + (struct ocfs2_refcount_block *)ref_leaf_bh->b_data; + struct ocfs2_refcount_list *rf_list = &rb->rf_records; + struct buffer_head *new_bh = NULL; + + BUG_ON(le32_to_cpu(rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL); + + if (rf_list->rl_used == rf_list->rl_count) { + u64 cpos = le64_to_cpu(rec->r_cpos); + u32 len = le32_to_cpu(rec->r_clusters); + + ret = ocfs2_expand_refcount_tree(handle, ci, ref_root_bh, + ref_leaf_bh, meta_ac); + if (ret) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_get_refcount_rec(ci, ref_root_bh, + cpos, len, NULL, &index, + &new_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + ref_leaf_bh = new_bh; + rb = (struct ocfs2_refcount_block *)ref_leaf_bh->b_data; + rf_list = &rb->rf_records; + } + + ret = ocfs2_journal_access_rb(handle, ci, ref_leaf_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto out; + } + + if (index < le16_to_cpu(rf_list->rl_used)) + memmove(&rf_list->rl_recs[index + 1], + &rf_list->rl_recs[index], + (le16_to_cpu(rf_list->rl_used) - index) * + sizeof(struct ocfs2_refcount_rec)); + + mlog(0, "insert refcount record start %llu, len %u, count %u " + "to leaf block %llu at index %d\n", + (unsigned long long)le64_to_cpu(rec->r_cpos), + le32_to_cpu(rec->r_clusters), le32_to_cpu(rec->r_refcount), + (unsigned long long)ref_leaf_bh->b_blocknr, index); + + rf_list->rl_recs[index] = *rec; + + le16_add_cpu(&rf_list->rl_used, 1); + + if (merge) + ocfs2_refcount_rec_merge(rb, index); + + ret = ocfs2_journal_dirty(handle, ref_leaf_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + if (index == 0) { + ret = ocfs2_adjust_refcount_rec(handle, ci, + ref_root_bh, + ref_leaf_bh, rec); + if (ret) + mlog_errno(ret); + } +out: + brelse(new_bh); + return ret; +} + +/* + * Split the refcount_rec indexed by "index" in ref_leaf_bh. + * This is much simple than our b-tree code. + * split_rec is the new refcount rec we want to insert. + * If split_rec->r_refcount > 0, we are changing the refcount(in case we + * increase refcount or decrease a refcount to non-zero). + * If split_rec->r_refcount == 0, we are punching a hole in current refcount + * rec( in case we decrease a refcount to zero). + */ +static int ocfs2_split_refcount_rec(handle_t *handle, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + struct buffer_head *ref_leaf_bh, + struct ocfs2_refcount_rec *split_rec, + int index, int merge, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc) +{ + int ret, recs_need; + u32 len; + struct ocfs2_refcount_block *rb = + (struct ocfs2_refcount_block *)ref_leaf_bh->b_data; + struct ocfs2_refcount_list *rf_list = &rb->rf_records; + struct ocfs2_refcount_rec *orig_rec = &rf_list->rl_recs[index]; + struct ocfs2_refcount_rec *tail_rec = NULL; + struct buffer_head *new_bh = NULL; + + BUG_ON(le32_to_cpu(rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL); + + mlog(0, "original r_pos %llu, cluster %u, split %llu, cluster %u\n", + le64_to_cpu(orig_rec->r_cpos), le32_to_cpu(orig_rec->r_clusters), + le64_to_cpu(split_rec->r_cpos), + le32_to_cpu(split_rec->r_clusters)); + + /* + * If we just need to split the header or tail clusters, + * no more recs are needed, just split is OK. + * Otherwise we at least need one new recs. + */ + if (!split_rec->r_refcount && + (split_rec->r_cpos == orig_rec->r_cpos || + le64_to_cpu(split_rec->r_cpos) + + le32_to_cpu(split_rec->r_clusters) == + le64_to_cpu(orig_rec->r_cpos) + le32_to_cpu(orig_rec->r_clusters))) + recs_need = 0; + else + recs_need = 1; + + /* + * We need one more rec if we split in the middle and the new rec have + * some refcount in it. + */ + if (split_rec->r_refcount && + (split_rec->r_cpos != orig_rec->r_cpos && + le64_to_cpu(split_rec->r_cpos) + + le32_to_cpu(split_rec->r_clusters) != + le64_to_cpu(orig_rec->r_cpos) + le32_to_cpu(orig_rec->r_clusters))) + recs_need++; + + /* If the leaf block don't have enough record, expand it. */ + if (le16_to_cpu(rf_list->rl_used) + recs_need > rf_list->rl_count) { + struct ocfs2_refcount_rec tmp_rec; + u64 cpos = le64_to_cpu(orig_rec->r_cpos); + len = le32_to_cpu(orig_rec->r_clusters); + ret = ocfs2_expand_refcount_tree(handle, ci, ref_root_bh, + ref_leaf_bh, meta_ac); + if (ret) { + mlog_errno(ret); + goto out; + } + + /* + * We have to re-get it since now cpos may be moved to + * another leaf block. + */ + ret = ocfs2_get_refcount_rec(ci, ref_root_bh, + cpos, len, &tmp_rec, &index, + &new_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + ref_leaf_bh = new_bh; + rb = (struct ocfs2_refcount_block *)ref_leaf_bh->b_data; + rf_list = &rb->rf_records; + orig_rec = &rf_list->rl_recs[index]; + } + + ret = ocfs2_journal_access_rb(handle, ci, ref_leaf_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto out; + } + + /* + * We have calculated out how many new records we need and store + * in recs_need, so spare enough space first by moving the records + * after "index" to the end. + */ + if (index != le16_to_cpu(rf_list->rl_used) - 1) + memmove(&rf_list->rl_recs[index + 1 + recs_need], + &rf_list->rl_recs[index + 1], + (le16_to_cpu(rf_list->rl_used) - index - 1) * + sizeof(struct ocfs2_refcount_rec)); + + len = (le64_to_cpu(orig_rec->r_cpos) + + le32_to_cpu(orig_rec->r_clusters)) - + (le64_to_cpu(split_rec->r_cpos) + + le32_to_cpu(split_rec->r_clusters)); + + /* + * If we have "len", the we will split in the tail and move it + * to the end of the space we have just spared. + */ + if (len) { + tail_rec = &rf_list->rl_recs[index + recs_need]; + + memcpy(tail_rec, orig_rec, sizeof(struct ocfs2_refcount_rec)); + le64_add_cpu(&tail_rec->r_cpos, + le32_to_cpu(tail_rec->r_clusters) - len); + tail_rec->r_clusters = le32_to_cpu(len); + } + + /* + * If the split pos isn't the same as the original one, we need to + * split in the head. + * + * Note: We have the chance that split_rec.r_refcount = 0, + * recs_need = 0 and len > 0, which means we just cut the head from + * the orig_rec and in that case we have done some modification in + * orig_rec above, so the check for r_cpos is faked. + */ + if (split_rec->r_cpos != orig_rec->r_cpos && tail_rec != orig_rec) { + len = le64_to_cpu(split_rec->r_cpos) - + le64_to_cpu(orig_rec->r_cpos); + orig_rec->r_clusters = cpu_to_le32(len); + index++; + } + + le16_add_cpu(&rf_list->rl_used, recs_need); + + if (split_rec->r_refcount) { + rf_list->rl_recs[index] = *split_rec; + mlog(0, "insert refcount record start %llu, len %u, count %u " + "to leaf block %llu at index %d\n", + (unsigned long long)le64_to_cpu(split_rec->r_cpos), + le32_to_cpu(split_rec->r_clusters), + le32_to_cpu(split_rec->r_refcount), + (unsigned long long)ref_leaf_bh->b_blocknr, index); + + if (merge) + ocfs2_refcount_rec_merge(rb, index); + } + + ret = ocfs2_journal_dirty(handle, ref_leaf_bh); + if (ret) + mlog_errno(ret); + +out: + brelse(new_bh); + return ret; +} + +static int __ocfs2_increase_refcount(handle_t *handle, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + u64 cpos, u32 len, int merge, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc) +{ + int ret = 0, index; + struct buffer_head *ref_leaf_bh = NULL; + struct ocfs2_refcount_rec rec; + unsigned int set_len = 0; + + mlog(0, "Tree owner %llu, add refcount start %llu, len %u\n", + (unsigned long long)ocfs2_metadata_cache_owner(ci), + (unsigned long long)cpos, len); + + while (len) { + ret = ocfs2_get_refcount_rec(ci, ref_root_bh, + cpos, len, &rec, &index, + &ref_leaf_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + set_len = le32_to_cpu(rec.r_clusters); + + /* + * Here we may meet with 3 situations: + * + * 1. If we find an already existing record, and the length + * is the same, cool, we just need to increase the r_refcount + * and it is OK. + * 2. If we find a hole, just insert it with r_refcount = 1. + * 3. If we are in the middle of one extent record, split + * it. + */ + if (rec.r_refcount && le64_to_cpu(rec.r_cpos) == cpos && + set_len <= len) { + mlog(0, "increase refcount rec, start %llu, len %u, " + "count %u\n", (unsigned long long)cpos, set_len, + le32_to_cpu(rec.r_refcount)); + ret = ocfs2_change_refcount_rec(handle, ci, + ref_leaf_bh, index, + merge, 1); + if (ret) { + mlog_errno(ret); + goto out; + } + } else if (!rec.r_refcount) { + rec.r_refcount = cpu_to_le32(1); + + mlog(0, "insert refcount rec, start %llu, len %u\n", + (unsigned long long)le64_to_cpu(rec.r_cpos), + set_len); + ret = ocfs2_insert_refcount_rec(handle, ci, ref_root_bh, + ref_leaf_bh, + &rec, index, + merge, meta_ac); + if (ret) { + mlog_errno(ret); + goto out; + } + } else { + set_len = min((u64)(cpos + len), + le64_to_cpu(rec.r_cpos) + set_len) - cpos; + rec.r_cpos = cpu_to_le64(cpos); + rec.r_clusters = cpu_to_le32(set_len); + le32_add_cpu(&rec.r_refcount, 1); + + mlog(0, "split refcount rec, start %llu, " + "len %u, count %u\n", + (unsigned long long)le64_to_cpu(rec.r_cpos), + set_len, le32_to_cpu(rec.r_refcount)); + ret = ocfs2_split_refcount_rec(handle, ci, + ref_root_bh, ref_leaf_bh, + &rec, index, merge, + meta_ac, dealloc); + if (ret) { + mlog_errno(ret); + goto out; + } + } + + cpos += set_len; + len -= set_len; + brelse(ref_leaf_bh); + ref_leaf_bh = NULL; + } + +out: + brelse(ref_leaf_bh); + return ret; +} + +static int ocfs2_remove_refcount_extent(handle_t *handle, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + struct buffer_head *ref_leaf_bh, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc) +{ + int ret; + struct super_block *sb = ocfs2_metadata_cache_get_super(ci); + struct ocfs2_refcount_block *rb = + (struct ocfs2_refcount_block *)ref_leaf_bh->b_data; + struct ocfs2_extent_tree et; + + BUG_ON(rb->rf_records.rl_used); + + ocfs2_init_refcount_extent_tree(&et, ci, ref_root_bh); + ret = ocfs2_remove_extent(handle, &et, le32_to_cpu(rb->rf_cpos), + 1, meta_ac, dealloc); + if (ret) { + mlog_errno(ret); + goto out; + } + + ocfs2_remove_from_cache(ci, ref_leaf_bh); + + /* + * add the freed block to the dealloc so that it will be freed + * when we run dealloc. + */ + ret = ocfs2_cache_block_dealloc(dealloc, EXTENT_ALLOC_SYSTEM_INODE, + le16_to_cpu(rb->rf_suballoc_slot), + le64_to_cpu(rb->rf_blkno), + le16_to_cpu(rb->rf_suballoc_bit)); + if (ret) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_journal_access_rb(handle, ci, ref_root_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto out; + } + + rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data; + + le32_add_cpu(&rb->rf_clusters, -1); + + /* + * check whether we need to restore the root refcount block if + * there is no leaf extent block at atll. + */ + if (!rb->rf_list.l_next_free_rec) { + BUG_ON(rb->rf_clusters); + + mlog(0, "reset refcount tree root %llu to be a record block.\n", + (unsigned long long)ref_root_bh->b_blocknr); + + rb->rf_flags = 0; + rb->rf_parent = 0; + rb->rf_cpos = 0; + memset(&rb->rf_records, 0, sb->s_blocksize - + offsetof(struct ocfs2_refcount_block, rf_records)); + rb->rf_records.rl_count = + cpu_to_le16(ocfs2_refcount_recs_per_rb(sb)); + } + + ocfs2_journal_dirty(handle, ref_root_bh); + +out: + return ret; +} + +int ocfs2_increase_refcount(handle_t *handle, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + u64 cpos, u32 len, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc) +{ + return __ocfs2_increase_refcount(handle, ci, ref_root_bh, + cpos, len, 1, + meta_ac, dealloc); +} + +static int ocfs2_decrease_refcount_rec(handle_t *handle, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + struct buffer_head *ref_leaf_bh, + int index, u64 cpos, unsigned int len, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc) +{ + int ret; + struct ocfs2_refcount_block *rb = + (struct ocfs2_refcount_block *)ref_leaf_bh->b_data; + struct ocfs2_refcount_rec *rec = &rb->rf_records.rl_recs[index]; + + BUG_ON(cpos < le64_to_cpu(rec->r_cpos)); + BUG_ON(cpos + len > + le64_to_cpu(rec->r_cpos) + le32_to_cpu(rec->r_clusters)); + + if (cpos == le64_to_cpu(rec->r_cpos) && + len == le32_to_cpu(rec->r_clusters)) + ret = ocfs2_change_refcount_rec(handle, ci, + ref_leaf_bh, index, 1, -1); + else { + struct ocfs2_refcount_rec split = *rec; + split.r_cpos = cpu_to_le64(cpos); + split.r_clusters = cpu_to_le32(len); + + le32_add_cpu(&split.r_refcount, -1); + + mlog(0, "split refcount rec, start %llu, " + "len %u, count %u, original start %llu, len %u\n", + (unsigned long long)le64_to_cpu(split.r_cpos), + len, le32_to_cpu(split.r_refcount), + (unsigned long long)le64_to_cpu(rec->r_cpos), + le32_to_cpu(rec->r_clusters)); + ret = ocfs2_split_refcount_rec(handle, ci, + ref_root_bh, ref_leaf_bh, + &split, index, 1, + meta_ac, dealloc); + } + + if (ret) { + mlog_errno(ret); + goto out; + } + + /* Remove the leaf refcount block if it contains no refcount record. */ + if (!rb->rf_records.rl_used && ref_leaf_bh != ref_root_bh) { + ret = ocfs2_remove_refcount_extent(handle, ci, ref_root_bh, + ref_leaf_bh, meta_ac, + dealloc); + if (ret) + mlog_errno(ret); + } + +out: + return ret; +} + +static int __ocfs2_decrease_refcount(handle_t *handle, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + u64 cpos, u32 len, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc, + int delete) +{ + int ret = 0, index = 0; + struct ocfs2_refcount_rec rec; + unsigned int r_count = 0, r_len; + struct super_block *sb = ocfs2_metadata_cache_get_super(ci); + struct buffer_head *ref_leaf_bh = NULL; + + mlog(0, "Tree owner %llu, decrease refcount start %llu, " + "len %u, delete %u\n", + (unsigned long long)ocfs2_metadata_cache_owner(ci), + (unsigned long long)cpos, len, delete); + + while (len) { + ret = ocfs2_get_refcount_rec(ci, ref_root_bh, + cpos, len, &rec, &index, + &ref_leaf_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + r_count = le32_to_cpu(rec.r_refcount); + BUG_ON(r_count == 0); + if (!delete) + BUG_ON(r_count > 1); + + r_len = min((u64)(cpos + len), le64_to_cpu(rec.r_cpos) + + le32_to_cpu(rec.r_clusters)) - cpos; + + ret = ocfs2_decrease_refcount_rec(handle, ci, ref_root_bh, + ref_leaf_bh, index, + cpos, r_len, + meta_ac, dealloc); + if (ret) { + mlog_errno(ret); + goto out; + } + + if (le32_to_cpu(rec.r_refcount) == 1 && delete) { + ret = ocfs2_cache_cluster_dealloc(dealloc, + ocfs2_clusters_to_blocks(sb, cpos), + r_len); + if (ret) { + mlog_errno(ret); + goto out; + } + } + + cpos += r_len; + len -= r_len; + brelse(ref_leaf_bh); + ref_leaf_bh = NULL; + } + +out: + brelse(ref_leaf_bh); + return ret; +} + +/* Caller must hold refcount tree lock. */ +int ocfs2_decrease_refcount(struct inode *inode, + handle_t *handle, u32 cpos, u32 len, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc, + int delete) +{ + int ret; + u64 ref_blkno; + struct ocfs2_inode_info *oi = OCFS2_I(inode); + struct buffer_head *ref_root_bh = NULL; + struct ocfs2_refcount_tree *tree; + + BUG_ON(!(oi->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL)); + + ret = ocfs2_get_refcount_block(inode, &ref_blkno); + if (ret) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_get_refcount_tree(OCFS2_SB(inode->i_sb), ref_blkno, &tree); + if (ret) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_read_refcount_block(&tree->rf_ci, tree->rf_blkno, + &ref_root_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + ret = __ocfs2_decrease_refcount(handle, &tree->rf_ci, ref_root_bh, + cpos, len, meta_ac, dealloc, delete); + if (ret) + mlog_errno(ret); +out: + brelse(ref_root_bh); + return ret; +} + +/* + * Mark the already-existing extent at cpos as refcounted for len clusters. + * This adds the refcount extent flag. + * + * If the existing extent is larger than the request, initiate a + * split. An attempt will be made at merging with adjacent extents. + * + * The caller is responsible for passing down meta_ac if we'll need it. + */ +static int ocfs2_mark_extent_refcounted(struct inode *inode, + struct ocfs2_extent_tree *et, + handle_t *handle, u32 cpos, + u32 len, u32 phys, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc) +{ + int ret; + + mlog(0, "Inode %lu refcount tree cpos %u, len %u, phys cluster %u\n", + inode->i_ino, cpos, len, phys); + + if (!ocfs2_refcount_tree(OCFS2_SB(inode->i_sb))) { + ocfs2_error(inode->i_sb, "Inode %lu want to use refcount " + "tree, but the feature bit is not set in the " + "super block.", inode->i_ino); + ret = -EROFS; + goto out; + } + + ret = ocfs2_change_extent_flag(handle, et, cpos, + len, phys, meta_ac, dealloc, + OCFS2_EXT_REFCOUNTED, 0); + if (ret) + mlog_errno(ret); + +out: + return ret; +} + +/* + * Given some contiguous physical clusters, calculate what we need + * for modifying their refcount. + */ +static int ocfs2_calc_refcount_meta_credits(struct super_block *sb, + struct ocfs2_caching_info *ci, + struct buffer_head *ref_root_bh, + u64 start_cpos, + u32 clusters, + int *meta_add, + int *credits) +{ + int ret = 0, index, ref_blocks = 0, recs_add = 0; + u64 cpos = start_cpos; + struct ocfs2_refcount_block *rb; + struct ocfs2_refcount_rec rec; + struct buffer_head *ref_leaf_bh = NULL, *prev_bh = NULL; + u32 len; + + mlog(0, "start_cpos %llu, clusters %u\n", + (unsigned long long)start_cpos, clusters); + while (clusters) { + ret = ocfs2_get_refcount_rec(ci, ref_root_bh, + cpos, clusters, &rec, + &index, &ref_leaf_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + if (ref_leaf_bh != prev_bh) { + /* + * Now we encounter a new leaf block, so calculate + * whether we need to extend the old leaf. + */ + if (prev_bh) { + rb = (struct ocfs2_refcount_block *) + prev_bh->b_data; + + if (le64_to_cpu(rb->rf_records.rl_used) + + recs_add > + le16_to_cpu(rb->rf_records.rl_count)) + ref_blocks++; + } + + recs_add = 0; + *credits += 1; + brelse(prev_bh); + prev_bh = ref_leaf_bh; + get_bh(prev_bh); + } + + rb = (struct ocfs2_refcount_block *)ref_leaf_bh->b_data; + + mlog(0, "recs_add %d,cpos %llu, clusters %u, rec->r_cpos %llu," + "rec->r_clusters %u, rec->r_refcount %u, index %d\n", + recs_add, (unsigned long long)cpos, clusters, + (unsigned long long)le64_to_cpu(rec.r_cpos), + le32_to_cpu(rec.r_clusters), + le32_to_cpu(rec.r_refcount), index); + + len = min((u64)cpos + clusters, le64_to_cpu(rec.r_cpos) + + le32_to_cpu(rec.r_clusters)) - cpos; + /* + * If the refcount rec already exist, cool. We just need + * to check whether there is a split. Otherwise we just need + * to increase the refcount. + * If we will insert one, increases recs_add. + * + * We record all the records which will be inserted to the + * same refcount block, so that we can tell exactly whether + * we need a new refcount block or not. + */ + if (rec.r_refcount) { + /* Check whether we need a split at the beginning. */ + if (cpos == start_cpos && + cpos != le64_to_cpu(rec.r_cpos)) + recs_add++; + + /* Check whether we need a split in the end. */ + if (cpos + clusters < le64_to_cpu(rec.r_cpos) + + le32_to_cpu(rec.r_clusters)) + recs_add++; + } else + recs_add++; + + brelse(ref_leaf_bh); + ref_leaf_bh = NULL; + clusters -= len; + cpos += len; + } + + if (prev_bh) { + rb = (struct ocfs2_refcount_block *)prev_bh->b_data; + + if (le64_to_cpu(rb->rf_records.rl_used) + recs_add > + le16_to_cpu(rb->rf_records.rl_count)) + ref_blocks++; + + *credits += 1; + } + + if (!ref_blocks) + goto out; + + mlog(0, "we need ref_blocks %d\n", ref_blocks); + *meta_add += ref_blocks; + *credits += ref_blocks; + + /* + * So we may need ref_blocks to insert into the tree. + * That also means we need to change the b-tree and add that number + * of records since we never merge them. + * We need one more block for expansion since the new created leaf + * block is also full and needs split. + */ + rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data; + if (le32_to_cpu(rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL) { + struct ocfs2_extent_tree et; + + ocfs2_init_refcount_extent_tree(&et, ci, ref_root_bh); + *meta_add += ocfs2_extend_meta_needed(et.et_root_el); + *credits += ocfs2_calc_extend_credits(sb, + et.et_root_el, + ref_blocks); + } else { + *credits += OCFS2_EXPAND_REFCOUNT_TREE_CREDITS; + *meta_add += 1; + } + +out: + brelse(ref_leaf_bh); + brelse(prev_bh); + return ret; +} + +/* + * For refcount tree, we will decrease some contiguous clusters + * refcount count, so just go through it to see how many blocks + * we gonna touch and whether we need to create new blocks. + * + * Normally the refcount blocks store these refcount should be + * continguous also, so that we can get the number easily. + * As for meta_ac, we will at most add split 2 refcount record and + * 2 more refcount block, so just check it in a rough way. + * + * Caller must hold refcount tree lock. + */ +int ocfs2_prepare_refcount_change_for_del(struct inode *inode, + struct buffer_head *di_bh, + u64 phys_blkno, + u32 clusters, + int *credits, + struct ocfs2_alloc_context **meta_ac) +{ + int ret, ref_blocks = 0; + struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data; + struct ocfs2_inode_info *oi = OCFS2_I(inode); + struct buffer_head *ref_root_bh = NULL; + struct ocfs2_refcount_tree *tree; + u64 start_cpos = ocfs2_blocks_to_clusters(inode->i_sb, phys_blkno); + + if (!ocfs2_refcount_tree(OCFS2_SB(inode->i_sb))) { + ocfs2_error(inode->i_sb, "Inode %lu want to use refcount " + "tree, but the feature bit is not set in the " + "super block.", inode->i_ino); + ret = -EROFS; + goto out; + } + + BUG_ON(!(oi->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL)); + + ret = ocfs2_get_refcount_tree(OCFS2_SB(inode->i_sb), + le64_to_cpu(di->i_refcount_loc), &tree); + if (ret) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_read_refcount_block(&tree->rf_ci, + le64_to_cpu(di->i_refcount_loc), + &ref_root_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_calc_refcount_meta_credits(inode->i_sb, + &tree->rf_ci, + ref_root_bh, + start_cpos, clusters, + &ref_blocks, credits); + if (ret) { + mlog_errno(ret); + goto out; + } + + mlog(0, "reserve new metadata %d, credits = %d\n", + ref_blocks, *credits); + + if (ref_blocks) { + ret = ocfs2_reserve_new_metadata_blocks(OCFS2_SB(inode->i_sb), + ref_blocks, meta_ac); + if (ret) + mlog_errno(ret); + } + +out: + brelse(ref_root_bh); + return ret; +} + +#define MAX_CONTIG_BYTES 1048576 + +static inline unsigned int ocfs2_cow_contig_clusters(struct super_block *sb) +{ + return ocfs2_clusters_for_bytes(sb, MAX_CONTIG_BYTES); +} + +static inline unsigned int ocfs2_cow_contig_mask(struct super_block *sb) +{ + return ~(ocfs2_cow_contig_clusters(sb) - 1); +} + +/* + * Given an extent that starts at 'start' and an I/O that starts at 'cpos', + * find an offset (start + (n * contig_clusters)) that is closest to cpos + * while still being less than or equal to it. + * + * The goal is to break the extent at a multiple of contig_clusters. + */ +static inline unsigned int ocfs2_cow_align_start(struct super_block *sb, + unsigned int start, + unsigned int cpos) +{ + BUG_ON(start > cpos); + + return start + ((cpos - start) & ocfs2_cow_contig_mask(sb)); +} + +/* + * Given a cluster count of len, pad it out so that it is a multiple + * of contig_clusters. + */ +static inline unsigned int ocfs2_cow_align_length(struct super_block *sb, + unsigned int len) +{ + unsigned int padded = + (len + (ocfs2_cow_contig_clusters(sb) - 1)) & + ocfs2_cow_contig_mask(sb); + + /* Did we wrap? */ + if (padded < len) + padded = UINT_MAX; + + return padded; +} + +/* + * Calculate out the start and number of virtual clusters we need to to CoW. + * + * cpos is vitual start cluster position we want to do CoW in a + * file and write_len is the cluster length. + * max_cpos is the place where we want to stop CoW intentionally. + * + * Normal we will start CoW from the beginning of extent record cotaining cpos. + * We try to break up extents on boundaries of MAX_CONTIG_BYTES so that we + * get good I/O from the resulting extent tree. + */ +static int ocfs2_refcount_cal_cow_clusters(struct inode *inode, + struct ocfs2_extent_list *el, + u32 cpos, + u32 write_len, + u32 max_cpos, + u32 *cow_start, + u32 *cow_len) +{ + int ret = 0; + int tree_height = le16_to_cpu(el->l_tree_depth), i; + struct buffer_head *eb_bh = NULL; + struct ocfs2_extent_block *eb = NULL; + struct ocfs2_extent_rec *rec; + unsigned int want_clusters, rec_end = 0; + int contig_clusters = ocfs2_cow_contig_clusters(inode->i_sb); + int leaf_clusters; + + BUG_ON(cpos + write_len > max_cpos); + + if (tree_height > 0) { + ret = ocfs2_find_leaf(INODE_CACHE(inode), el, cpos, &eb_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + eb = (struct ocfs2_extent_block *) eb_bh->b_data; + el = &eb->h_list; + + if (el->l_tree_depth) { + ocfs2_error(inode->i_sb, + "Inode %lu has non zero tree depth in " + "leaf block %llu\n", inode->i_ino, + (unsigned long long)eb_bh->b_blocknr); + ret = -EROFS; + goto out; + } + } + + *cow_len = 0; + for (i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) { + rec = &el->l_recs[i]; + + if (ocfs2_is_empty_extent(rec)) { + mlog_bug_on_msg(i != 0, "Inode %lu has empty record in " + "index %d\n", inode->i_ino, i); + continue; + } + + if (le32_to_cpu(rec->e_cpos) + + le16_to_cpu(rec->e_leaf_clusters) <= cpos) + continue; + + if (*cow_len == 0) { + /* + * We should find a refcounted record in the + * first pass. + */ + BUG_ON(!(rec->e_flags & OCFS2_EXT_REFCOUNTED)); + *cow_start = le32_to_cpu(rec->e_cpos); + } + + /* + * If we encounter a hole, a non-refcounted record or + * pass the max_cpos, stop the search. + */ + if ((!(rec->e_flags & OCFS2_EXT_REFCOUNTED)) || + (*cow_len && rec_end != le32_to_cpu(rec->e_cpos)) || + (max_cpos <= le32_to_cpu(rec->e_cpos))) + break; + + leaf_clusters = le16_to_cpu(rec->e_leaf_clusters); + rec_end = le32_to_cpu(rec->e_cpos) + leaf_clusters; + if (rec_end > max_cpos) { + rec_end = max_cpos; + leaf_clusters = rec_end - le32_to_cpu(rec->e_cpos); + } + + /* + * How many clusters do we actually need from + * this extent? First we see how many we actually + * need to complete the write. If that's smaller + * than contig_clusters, we try for contig_clusters. + */ + if (!*cow_len) + want_clusters = write_len; + else + want_clusters = (cpos + write_len) - + (*cow_start + *cow_len); + if (want_clusters < contig_clusters) + want_clusters = contig_clusters; + + /* + * If the write does not cover the whole extent, we + * need to calculate how we're going to split the extent. + * We try to do it on contig_clusters boundaries. + * + * Any extent smaller than contig_clusters will be + * CoWed in its entirety. + */ + if (leaf_clusters <= contig_clusters) + *cow_len += leaf_clusters; + else if (*cow_len || (*cow_start == cpos)) { + /* + * This extent needs to be CoW'd from its + * beginning, so all we have to do is compute + * how many clusters to grab. We align + * want_clusters to the edge of contig_clusters + * to get better I/O. + */ + want_clusters = ocfs2_cow_align_length(inode->i_sb, + want_clusters); + + if (leaf_clusters < want_clusters) + *cow_len += leaf_clusters; + else + *cow_len += want_clusters; + } else if ((*cow_start + contig_clusters) >= + (cpos + write_len)) { + /* + * Breaking off contig_clusters at the front + * of the extent will cover our write. That's + * easy. + */ + *cow_len = contig_clusters; + } else if ((rec_end - cpos) <= contig_clusters) { + /* + * Breaking off contig_clusters at the tail of + * this extent will cover cpos. + */ + *cow_start = rec_end - contig_clusters; + *cow_len = contig_clusters; + } else if ((rec_end - cpos) <= want_clusters) { + /* + * While we can't fit the entire write in this + * extent, we know that the write goes from cpos + * to the end of the extent. Break that off. + * We try to break it at some multiple of + * contig_clusters from the front of the extent. + * Failing that (ie, cpos is within + * contig_clusters of the front), we'll CoW the + * entire extent. + */ + *cow_start = ocfs2_cow_align_start(inode->i_sb, + *cow_start, cpos); + *cow_len = rec_end - *cow_start; + } else { + /* + * Ok, the entire write lives in the middle of + * this extent. Let's try to slice the extent up + * nicely. Optimally, our CoW region starts at + * m*contig_clusters from the beginning of the + * extent and goes for n*contig_clusters, + * covering the entire write. + */ + *cow_start = ocfs2_cow_align_start(inode->i_sb, + *cow_start, cpos); + + want_clusters = (cpos + write_len) - *cow_start; + want_clusters = ocfs2_cow_align_length(inode->i_sb, + want_clusters); + if (*cow_start + want_clusters <= rec_end) + *cow_len = want_clusters; + else + *cow_len = rec_end - *cow_start; + } + + /* Have we covered our entire write yet? */ + if ((*cow_start + *cow_len) >= (cpos + write_len)) + break; + + /* + * If we reach the end of the extent block and don't get enough + * clusters, continue with the next extent block if possible. + */ + if (i + 1 == le16_to_cpu(el->l_next_free_rec) && + eb && eb->h_next_leaf_blk) { + brelse(eb_bh); + eb_bh = NULL; + + ret = ocfs2_read_extent_block(INODE_CACHE(inode), + le64_to_cpu(eb->h_next_leaf_blk), + &eb_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + eb = (struct ocfs2_extent_block *) eb_bh->b_data; + el = &eb->h_list; + i = -1; + } + } + +out: + brelse(eb_bh); + return ret; +} + +/* + * Prepare meta_ac, data_ac and calculate credits when we want to add some + * num_clusters in data_tree "et" and change the refcount for the old + * clusters(starting form p_cluster) in the refcount tree. + * + * Note: + * 1. since we may split the old tree, so we at most will need num_clusters + 2 + * more new leaf records. + * 2. In some case, we may not need to reserve new clusters(e.g, reflink), so + * just give data_ac = NULL. + */ +static int ocfs2_lock_refcount_allocators(struct super_block *sb, + u32 p_cluster, u32 num_clusters, + struct ocfs2_extent_tree *et, + struct ocfs2_caching_info *ref_ci, + struct buffer_head *ref_root_bh, + struct ocfs2_alloc_context **meta_ac, + struct ocfs2_alloc_context **data_ac, + int *credits) +{ + int ret = 0, meta_add = 0; + int num_free_extents = ocfs2_num_free_extents(OCFS2_SB(sb), et); + + if (num_free_extents < 0) { + ret = num_free_extents; + mlog_errno(ret); + goto out; + } + + if (num_free_extents < num_clusters + 2) + meta_add = + ocfs2_extend_meta_needed(et->et_root_el); + + *credits += ocfs2_calc_extend_credits(sb, et->et_root_el, + num_clusters + 2); + + ret = ocfs2_calc_refcount_meta_credits(sb, ref_ci, ref_root_bh, + p_cluster, num_clusters, + &meta_add, credits); + if (ret) { + mlog_errno(ret); + goto out; + } + + mlog(0, "reserve new metadata %d, clusters %u, credits = %d\n", + meta_add, num_clusters, *credits); + ret = ocfs2_reserve_new_metadata_blocks(OCFS2_SB(sb), meta_add, + meta_ac); + if (ret) { + mlog_errno(ret); + goto out; + } + + if (data_ac) { + ret = ocfs2_reserve_clusters(OCFS2_SB(sb), num_clusters, + data_ac); + if (ret) + mlog_errno(ret); + } + +out: + if (ret) { + if (*meta_ac) { + ocfs2_free_alloc_context(*meta_ac); + *meta_ac = NULL; + } + } + + return ret; +} + +static int ocfs2_clear_cow_buffer(handle_t *handle, struct buffer_head *bh) +{ + BUG_ON(buffer_dirty(bh)); + + clear_buffer_mapped(bh); + + return 0; +} + +static int ocfs2_duplicate_clusters_by_page(handle_t *handle, + struct ocfs2_cow_context *context, + u32 cpos, u32 old_cluster, + u32 new_cluster, u32 new_len) +{ + int ret = 0, partial; + struct ocfs2_caching_info *ci = context->data_et.et_ci; + struct super_block *sb = ocfs2_metadata_cache_get_super(ci); + u64 new_block = ocfs2_clusters_to_blocks(sb, new_cluster); + struct page *page; + pgoff_t page_index; + unsigned int from, to; + loff_t offset, end, map_end; + struct address_space *mapping = context->inode->i_mapping; + + mlog(0, "old_cluster %u, new %u, len %u at offset %u\n", old_cluster, + new_cluster, new_len, cpos); + + offset = ((loff_t)cpos) << OCFS2_SB(sb)->s_clustersize_bits; + end = offset + (new_len << OCFS2_SB(sb)->s_clustersize_bits); + + while (offset < end) { + page_index = offset >> PAGE_CACHE_SHIFT; + map_end = (page_index + 1) << PAGE_CACHE_SHIFT; + if (map_end > end) + map_end = end; + + /* from, to is the offset within the page. */ + from = offset & (PAGE_CACHE_SIZE - 1); + to = PAGE_CACHE_SIZE; + if (map_end & (PAGE_CACHE_SIZE - 1)) + to = map_end & (PAGE_CACHE_SIZE - 1); + + page = grab_cache_page(mapping, page_index); + + /* This page can't be dirtied before we CoW it out. */ + BUG_ON(PageDirty(page)); + + if (!PageUptodate(page)) { + ret = block_read_full_page(page, ocfs2_get_block); + if (ret) { + mlog_errno(ret); + goto unlock; + } + lock_page(page); + } + + if (page_has_buffers(page)) { + ret = walk_page_buffers(handle, page_buffers(page), + from, to, &partial, + ocfs2_clear_cow_buffer); + if (ret) { + mlog_errno(ret); + goto unlock; + } + } + + ocfs2_map_and_dirty_page(context->inode, + handle, from, to, + page, 0, &new_block); + mark_page_accessed(page); +unlock: + unlock_page(page); + page_cache_release(page); + page = NULL; + offset = map_end; + if (ret) + break; + } + + return ret; +} + +static int ocfs2_duplicate_clusters_by_jbd(handle_t *handle, + struct ocfs2_cow_context *context, + u32 cpos, u32 old_cluster, + u32 new_cluster, u32 new_len) +{ + int ret = 0; + struct super_block *sb = context->inode->i_sb; + struct ocfs2_caching_info *ci = context->data_et.et_ci; + int i, blocks = ocfs2_clusters_to_blocks(sb, new_len); + u64 old_block = ocfs2_clusters_to_blocks(sb, old_cluster); + u64 new_block = ocfs2_clusters_to_blocks(sb, new_cluster); + struct ocfs2_super *osb = OCFS2_SB(sb); + struct buffer_head *old_bh = NULL; + struct buffer_head *new_bh = NULL; + + mlog(0, "old_cluster %u, new %u, len %u\n", old_cluster, + new_cluster, new_len); + + for (i = 0; i < blocks; i++, old_block++, new_block++) { + new_bh = sb_getblk(osb->sb, new_block); + if (new_bh == NULL) { + ret = -EIO; + mlog_errno(ret); + break; + } + + ocfs2_set_new_buffer_uptodate(ci, new_bh); + + ret = ocfs2_read_block(ci, old_block, &old_bh, NULL); + if (ret) { + mlog_errno(ret); + break; + } + + ret = ocfs2_journal_access(handle, ci, new_bh, + OCFS2_JOURNAL_ACCESS_CREATE); + if (ret) { + mlog_errno(ret); + break; + } + + memcpy(new_bh->b_data, old_bh->b_data, sb->s_blocksize); + ret = ocfs2_journal_dirty(handle, new_bh); + if (ret) { + mlog_errno(ret); + break; + } + + brelse(new_bh); + brelse(old_bh); + new_bh = NULL; + old_bh = NULL; + } + + brelse(new_bh); + brelse(old_bh); + return ret; +} + +static int ocfs2_clear_ext_refcount(handle_t *handle, + struct ocfs2_extent_tree *et, + u32 cpos, u32 p_cluster, u32 len, + unsigned int ext_flags, + struct ocfs2_alloc_context *meta_ac, + struct ocfs2_cached_dealloc_ctxt *dealloc) +{ + int ret, index; + struct ocfs2_extent_rec replace_rec; + struct ocfs2_path *path = NULL; + struct ocfs2_extent_list *el; + struct super_block *sb = ocfs2_metadata_cache_get_super(et->et_ci); + u64 ino = ocfs2_metadata_cache_owner(et->et_ci); + + mlog(0, "inode %llu cpos %u, len %u, p_cluster %u, ext_flags %u\n", + (unsigned long long)ino, cpos, len, p_cluster, ext_flags); + + memset(&replace_rec, 0, sizeof(replace_rec)); + replace_rec.e_cpos = cpu_to_le32(cpos); + replace_rec.e_leaf_clusters = cpu_to_le16(len); + replace_rec.e_blkno = cpu_to_le64(ocfs2_clusters_to_blocks(sb, + p_cluster)); + replace_rec.e_flags = ext_flags; + replace_rec.e_flags &= ~OCFS2_EXT_REFCOUNTED; + + path = ocfs2_new_path_from_et(et); + if (!path) { + ret = -ENOMEM; + mlog_errno(ret); + goto out; + } + + ret = ocfs2_find_path(et->et_ci, path, cpos); + if (ret) { + mlog_errno(ret); + goto out; + } + + el = path_leaf_el(path); + + index = ocfs2_search_extent_list(el, cpos); + if (index == -1 || index >= le16_to_cpu(el->l_next_free_rec)) { + ocfs2_error(sb, + "Inode %llu has an extent at cpos %u which can no " + "longer be found.\n", + (unsigned long long)ino, cpos); + ret = -EROFS; + goto out; + } + + ret = ocfs2_split_extent(handle, et, path, index, + &replace_rec, meta_ac, dealloc); + if (ret) + mlog_errno(ret); + +out: + ocfs2_free_path(path); + return ret; +} + +static int ocfs2_replace_clusters(handle_t *handle, + struct ocfs2_cow_context *context, + u32 cpos, u32 old, + u32 new, u32 len, + unsigned int ext_flags) +{ + int ret; + struct ocfs2_caching_info *ci = context->data_et.et_ci; + u64 ino = ocfs2_metadata_cache_owner(ci); + + mlog(0, "inode %llu, cpos %u, old %u, new %u, len %u, ext_flags %u\n", + (unsigned long long)ino, cpos, old, new, len, ext_flags); + + /*If the old clusters is unwritten, no need to duplicate. */ + if (!(ext_flags & OCFS2_EXT_UNWRITTEN)) { + ret = context->cow_duplicate_clusters(handle, context, cpos, + old, new, len); + if (ret) { + mlog_errno(ret); + goto out; + } + } + + ret = ocfs2_clear_ext_refcount(handle, &context->data_et, + cpos, new, len, ext_flags, + context->meta_ac, &context->dealloc); + if (ret) + mlog_errno(ret); +out: + return ret; +} + +static int ocfs2_cow_sync_writeback(struct super_block *sb, + struct ocfs2_cow_context *context, + u32 cpos, u32 num_clusters) +{ + int ret = 0; + loff_t offset, end, map_end; + pgoff_t page_index; + struct page *page; + + if (ocfs2_should_order_data(context->inode)) + return 0; + + offset = ((loff_t)cpos) << OCFS2_SB(sb)->s_clustersize_bits; + end = offset + (num_clusters << OCFS2_SB(sb)->s_clustersize_bits); + + ret = filemap_fdatawrite_range(context->inode->i_mapping, + offset, end - 1); + if (ret < 0) { + mlog_errno(ret); + return ret; + } + + while (offset < end) { + page_index = offset >> PAGE_CACHE_SHIFT; + map_end = (page_index + 1) << PAGE_CACHE_SHIFT; + if (map_end > end) + map_end = end; + + page = grab_cache_page(context->inode->i_mapping, page_index); + BUG_ON(!page); + + wait_on_page_writeback(page); + if (PageError(page)) { + ret = -EIO; + mlog_errno(ret); + } else + mark_page_accessed(page); + + unlock_page(page); + page_cache_release(page); + page = NULL; + offset = map_end; + if (ret) + break; + } + + return ret; +} + +static int ocfs2_di_get_clusters(struct ocfs2_cow_context *context, + u32 v_cluster, u32 *p_cluster, + u32 *num_clusters, + unsigned int *extent_flags) +{ + return ocfs2_get_clusters(context->inode, v_cluster, p_cluster, + num_clusters, extent_flags); +} + +static int ocfs2_make_clusters_writable(struct super_block *sb, + struct ocfs2_cow_context *context, + u32 cpos, u32 p_cluster, + u32 num_clusters, unsigned int e_flags) +{ + int ret, delete, index, credits = 0; + u32 new_bit, new_len; + unsigned int set_len; + struct ocfs2_super *osb = OCFS2_SB(sb); + handle_t *handle; + struct buffer_head *ref_leaf_bh = NULL; + struct ocfs2_caching_info *ref_ci = &context->ref_tree->rf_ci; + struct ocfs2_refcount_rec rec; + + mlog(0, "cpos %u, p_cluster %u, num_clusters %u, e_flags %u\n", + cpos, p_cluster, num_clusters, e_flags); + + ret = ocfs2_lock_refcount_allocators(sb, p_cluster, num_clusters, + &context->data_et, + ref_ci, + context->ref_root_bh, + &context->meta_ac, + &context->data_ac, &credits); + if (ret) { + mlog_errno(ret); + return ret; + } + + if (context->post_refcount) + credits += context->post_refcount->credits; + + credits += context->extra_credits; + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto out; + } + + while (num_clusters) { + ret = ocfs2_get_refcount_rec(ref_ci, context->ref_root_bh, + p_cluster, num_clusters, + &rec, &index, &ref_leaf_bh); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + + BUG_ON(!rec.r_refcount); + set_len = min((u64)p_cluster + num_clusters, + le64_to_cpu(rec.r_cpos) + + le32_to_cpu(rec.r_clusters)) - p_cluster; + + /* + * There are many different situation here. + * 1. If refcount == 1, remove the flag and don't COW. + * 2. If refcount > 1, allocate clusters. + * Here we may not allocate r_len once at a time, so continue + * until we reach num_clusters. + */ + if (le32_to_cpu(rec.r_refcount) == 1) { + delete = 0; + ret = ocfs2_clear_ext_refcount(handle, + &context->data_et, + cpos, p_cluster, + set_len, e_flags, + context->meta_ac, + &context->dealloc); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + } else { + delete = 1; + + ret = __ocfs2_claim_clusters(osb, handle, + context->data_ac, + 1, set_len, + &new_bit, &new_len); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + + ret = ocfs2_replace_clusters(handle, context, + cpos, p_cluster, new_bit, + new_len, e_flags); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + set_len = new_len; + } + + ret = __ocfs2_decrease_refcount(handle, ref_ci, + context->ref_root_bh, + p_cluster, set_len, + context->meta_ac, + &context->dealloc, delete); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + + cpos += set_len; + p_cluster += set_len; + num_clusters -= set_len; + brelse(ref_leaf_bh); + ref_leaf_bh = NULL; + } + + /* handle any post_cow action. */ + if (context->post_refcount && context->post_refcount->func) { + ret = context->post_refcount->func(context->inode, handle, + context->post_refcount->para); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + } + + /* + * Here we should write the new page out first if we are + * in write-back mode. + */ + if (context->get_clusters == ocfs2_di_get_clusters) { + ret = ocfs2_cow_sync_writeback(sb, context, cpos, num_clusters); + if (ret) + mlog_errno(ret); + } + +out_commit: + ocfs2_commit_trans(osb, handle); + +out: + if (context->data_ac) { + ocfs2_free_alloc_context(context->data_ac); + context->data_ac = NULL; + } + if (context->meta_ac) { + ocfs2_free_alloc_context(context->meta_ac); + context->meta_ac = NULL; + } + brelse(ref_leaf_bh); + + return ret; +} + +static int ocfs2_replace_cow(struct ocfs2_cow_context *context) +{ + int ret = 0; + struct inode *inode = context->inode; + u32 cow_start = context->cow_start, cow_len = context->cow_len; + u32 p_cluster, num_clusters; + unsigned int ext_flags; + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + + if (!ocfs2_refcount_tree(OCFS2_SB(inode->i_sb))) { + ocfs2_error(inode->i_sb, "Inode %lu want to use refcount " + "tree, but the feature bit is not set in the " + "super block.", inode->i_ino); + return -EROFS; + } + + ocfs2_init_dealloc_ctxt(&context->dealloc); + + while (cow_len) { + ret = context->get_clusters(context, cow_start, &p_cluster, + &num_clusters, &ext_flags); + if (ret) { + mlog_errno(ret); + break; + } + + BUG_ON(!(ext_flags & OCFS2_EXT_REFCOUNTED)); + + if (cow_len < num_clusters) + num_clusters = cow_len; + + ret = ocfs2_make_clusters_writable(inode->i_sb, context, + cow_start, p_cluster, + num_clusters, ext_flags); + if (ret) { + mlog_errno(ret); + break; + } + + cow_len -= num_clusters; + cow_start += num_clusters; + } + + if (ocfs2_dealloc_has_cluster(&context->dealloc)) { + ocfs2_schedule_truncate_log_flush(osb, 1); + ocfs2_run_deallocs(osb, &context->dealloc); + } + + return ret; +} + +/* + * Starting at cpos, try to CoW write_len clusters. Don't CoW + * past max_cpos. This will stop when it runs into a hole or an + * unrefcounted extent. + */ +static int ocfs2_refcount_cow_hunk(struct inode *inode, + struct buffer_head *di_bh, + u32 cpos, u32 write_len, u32 max_cpos) +{ + int ret; + u32 cow_start = 0, cow_len = 0; + struct ocfs2_inode_info *oi = OCFS2_I(inode); + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data; + struct buffer_head *ref_root_bh = NULL; + struct ocfs2_refcount_tree *ref_tree; + struct ocfs2_cow_context *context = NULL; + + BUG_ON(!(oi->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL)); + + ret = ocfs2_refcount_cal_cow_clusters(inode, &di->id2.i_list, + cpos, write_len, max_cpos, + &cow_start, &cow_len); + if (ret) { + mlog_errno(ret); + goto out; + } + + mlog(0, "CoW inode %lu, cpos %u, write_len %u, cow_start %u, " + "cow_len %u\n", inode->i_ino, + cpos, write_len, cow_start, cow_len); + + BUG_ON(cow_len == 0); + + context = kzalloc(sizeof(struct ocfs2_cow_context), GFP_NOFS); + if (!context) { + ret = -ENOMEM; + mlog_errno(ret); + goto out; + } + + ret = ocfs2_lock_refcount_tree(osb, le64_to_cpu(di->i_refcount_loc), + 1, &ref_tree, &ref_root_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + context->inode = inode; + context->cow_start = cow_start; + context->cow_len = cow_len; + context->ref_tree = ref_tree; + context->ref_root_bh = ref_root_bh; + context->cow_duplicate_clusters = ocfs2_duplicate_clusters_by_page; + context->get_clusters = ocfs2_di_get_clusters; + + ocfs2_init_dinode_extent_tree(&context->data_et, + INODE_CACHE(inode), di_bh); + + ret = ocfs2_replace_cow(context); + if (ret) + mlog_errno(ret); + + /* + * truncate the extent map here since no matter whether we meet with + * any error during the action, we shouldn't trust cached extent map + * any more. + */ + ocfs2_extent_map_trunc(inode, cow_start); + + ocfs2_unlock_refcount_tree(osb, ref_tree, 1); + brelse(ref_root_bh); +out: + kfree(context); + return ret; +} + +/* + * CoW any and all clusters between cpos and cpos+write_len. + * Don't CoW past max_cpos. If this returns successfully, all + * clusters between cpos and cpos+write_len are safe to modify. + */ +int ocfs2_refcount_cow(struct inode *inode, + struct buffer_head *di_bh, + u32 cpos, u32 write_len, u32 max_cpos) +{ + int ret = 0; + u32 p_cluster, num_clusters; + unsigned int ext_flags; + + while (write_len) { + ret = ocfs2_get_clusters(inode, cpos, &p_cluster, + &num_clusters, &ext_flags); + if (ret) { + mlog_errno(ret); + break; + } + + if (write_len < num_clusters) + num_clusters = write_len; + + if (ext_flags & OCFS2_EXT_REFCOUNTED) { + ret = ocfs2_refcount_cow_hunk(inode, di_bh, cpos, + num_clusters, max_cpos); + if (ret) { + mlog_errno(ret); + break; + } + } + + write_len -= num_clusters; + cpos += num_clusters; + } + + return ret; +} + +static int ocfs2_xattr_value_get_clusters(struct ocfs2_cow_context *context, + u32 v_cluster, u32 *p_cluster, + u32 *num_clusters, + unsigned int *extent_flags) +{ + struct inode *inode = context->inode; + struct ocfs2_xattr_value_root *xv = context->cow_object; + + return ocfs2_xattr_get_clusters(inode, v_cluster, p_cluster, + num_clusters, &xv->xr_list, + extent_flags); +} + +/* + * Given a xattr value root, calculate the most meta/credits we need for + * refcount tree change if we truncate it to 0. + */ +int ocfs2_refcounted_xattr_delete_need(struct inode *inode, + struct ocfs2_caching_info *ref_ci, + struct buffer_head *ref_root_bh, + struct ocfs2_xattr_value_root *xv, + int *meta_add, int *credits) +{ + int ret = 0, index, ref_blocks = 0; + u32 p_cluster, num_clusters; + u32 cpos = 0, clusters = le32_to_cpu(xv->xr_clusters); + struct ocfs2_refcount_block *rb; + struct ocfs2_refcount_rec rec; + struct buffer_head *ref_leaf_bh = NULL; + + while (cpos < clusters) { + ret = ocfs2_xattr_get_clusters(inode, cpos, &p_cluster, + &num_clusters, &xv->xr_list, + NULL); + if (ret) { + mlog_errno(ret); + goto out; + } + + cpos += num_clusters; + + while (num_clusters) { + ret = ocfs2_get_refcount_rec(ref_ci, ref_root_bh, + p_cluster, num_clusters, + &rec, &index, + &ref_leaf_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + BUG_ON(!rec.r_refcount); + + rb = (struct ocfs2_refcount_block *)ref_leaf_bh->b_data; + + /* + * We really don't know whether the other clusters is in + * this refcount block or not, so just take the worst + * case that all the clusters are in this block and each + * one will split a refcount rec, so totally we need + * clusters * 2 new refcount rec. + */ + if (le64_to_cpu(rb->rf_records.rl_used) + clusters * 2 > + le16_to_cpu(rb->rf_records.rl_count)) + ref_blocks++; + + *credits += 1; + brelse(ref_leaf_bh); + ref_leaf_bh = NULL; + + if (num_clusters <= le32_to_cpu(rec.r_clusters)) + break; + else + num_clusters -= le32_to_cpu(rec.r_clusters); + p_cluster += num_clusters; + } + } + + *meta_add += ref_blocks; + if (!ref_blocks) + goto out; + + rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data; + if (le32_to_cpu(rb->rf_flags) & OCFS2_REFCOUNT_TREE_FL) + *credits += OCFS2_EXPAND_REFCOUNT_TREE_CREDITS; + else { + struct ocfs2_extent_tree et; + + ocfs2_init_refcount_extent_tree(&et, ref_ci, ref_root_bh); + *credits += ocfs2_calc_extend_credits(inode->i_sb, + et.et_root_el, + ref_blocks); + } + +out: + brelse(ref_leaf_bh); + return ret; +} + +/* + * Do CoW for xattr. + */ +int ocfs2_refcount_cow_xattr(struct inode *inode, + struct ocfs2_dinode *di, + struct ocfs2_xattr_value_buf *vb, + struct ocfs2_refcount_tree *ref_tree, + struct buffer_head *ref_root_bh, + u32 cpos, u32 write_len, + struct ocfs2_post_refcount *post) +{ + int ret; + struct ocfs2_xattr_value_root *xv = vb->vb_xv; + struct ocfs2_inode_info *oi = OCFS2_I(inode); + struct ocfs2_cow_context *context = NULL; + u32 cow_start, cow_len; + + BUG_ON(!(oi->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL)); + + ret = ocfs2_refcount_cal_cow_clusters(inode, &xv->xr_list, + cpos, write_len, UINT_MAX, + &cow_start, &cow_len); + if (ret) { + mlog_errno(ret); + goto out; + } + + BUG_ON(cow_len == 0); + + context = kzalloc(sizeof(struct ocfs2_cow_context), GFP_NOFS); + if (!context) { + ret = -ENOMEM; + mlog_errno(ret); + goto out; + } + + context->inode = inode; + context->cow_start = cow_start; + context->cow_len = cow_len; + context->ref_tree = ref_tree; + context->ref_root_bh = ref_root_bh;; + context->cow_object = xv; + + context->cow_duplicate_clusters = ocfs2_duplicate_clusters_by_jbd; + /* We need the extra credits for duplicate_clusters by jbd. */ + context->extra_credits = + ocfs2_clusters_to_blocks(inode->i_sb, 1) * cow_len; + context->get_clusters = ocfs2_xattr_value_get_clusters; + context->post_refcount = post; + + ocfs2_init_xattr_value_extent_tree(&context->data_et, + INODE_CACHE(inode), vb); + + ret = ocfs2_replace_cow(context); + if (ret) + mlog_errno(ret); + +out: + kfree(context); + return ret; +} + +/* + * Insert a new extent into refcount tree and mark a extent rec + * as refcounted in the dinode tree. + */ +int ocfs2_add_refcount_flag(struct inode *inode, + struct ocfs2_extent_tree *data_et, + struct ocfs2_caching_info *ref_ci, + struct buffer_head *ref_root_bh, + u32 cpos, u32 p_cluster, u32 num_clusters, + struct ocfs2_cached_dealloc_ctxt *dealloc, + struct ocfs2_post_refcount *post) +{ + int ret; + handle_t *handle; + int credits = 1, ref_blocks = 0; + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + struct ocfs2_alloc_context *meta_ac = NULL; + + ret = ocfs2_calc_refcount_meta_credits(inode->i_sb, + ref_ci, ref_root_bh, + p_cluster, num_clusters, + &ref_blocks, &credits); + if (ret) { + mlog_errno(ret); + goto out; + } + + mlog(0, "reserve new metadata %d, credits = %d\n", + ref_blocks, credits); + + if (ref_blocks) { + ret = ocfs2_reserve_new_metadata_blocks(OCFS2_SB(inode->i_sb), + ref_blocks, &meta_ac); + if (ret) { + mlog_errno(ret); + goto out; + } + } + + if (post) + credits += post->credits; + + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto out; + } + + ret = ocfs2_mark_extent_refcounted(inode, data_et, handle, + cpos, num_clusters, p_cluster, + meta_ac, dealloc); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + + ret = __ocfs2_increase_refcount(handle, ref_ci, ref_root_bh, + p_cluster, num_clusters, 0, + meta_ac, dealloc); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + + if (post && post->func) { + ret = post->func(inode, handle, post->para); + if (ret) + mlog_errno(ret); + } + +out_commit: + ocfs2_commit_trans(osb, handle); +out: + if (meta_ac) + ocfs2_free_alloc_context(meta_ac); + return ret; +} + +static int ocfs2_change_ctime(struct inode *inode, + struct buffer_head *di_bh) +{ + int ret; + handle_t *handle; + struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data; + + handle = ocfs2_start_trans(OCFS2_SB(inode->i_sb), + OCFS2_INODE_UPDATE_CREDITS); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto out; + } + + ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + + inode->i_ctime = CURRENT_TIME; + di->i_ctime = cpu_to_le64(inode->i_ctime.tv_sec); + di->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec); + + ocfs2_journal_dirty(handle, di_bh); + +out_commit: + ocfs2_commit_trans(OCFS2_SB(inode->i_sb), handle); +out: + return ret; +} + +static int ocfs2_attach_refcount_tree(struct inode *inode, + struct buffer_head *di_bh) +{ + int ret, data_changed = 0; + struct buffer_head *ref_root_bh = NULL; + struct ocfs2_inode_info *oi = OCFS2_I(inode); + struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data; + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + struct ocfs2_refcount_tree *ref_tree; + unsigned int ext_flags; + loff_t size; + u32 cpos, num_clusters, clusters, p_cluster; + struct ocfs2_cached_dealloc_ctxt dealloc; + struct ocfs2_extent_tree di_et; + + ocfs2_init_dealloc_ctxt(&dealloc); + + if (!(oi->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL)) { + ret = ocfs2_create_refcount_tree(inode, di_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + } + + BUG_ON(!di->i_refcount_loc); + ret = ocfs2_lock_refcount_tree(osb, + le64_to_cpu(di->i_refcount_loc), 1, + &ref_tree, &ref_root_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + ocfs2_init_dinode_extent_tree(&di_et, INODE_CACHE(inode), di_bh); + + size = i_size_read(inode); + clusters = ocfs2_clusters_for_bytes(inode->i_sb, size); + + cpos = 0; + while (cpos < clusters) { + ret = ocfs2_get_clusters(inode, cpos, &p_cluster, + &num_clusters, &ext_flags); + + if (p_cluster && !(ext_flags & OCFS2_EXT_REFCOUNTED)) { + ret = ocfs2_add_refcount_flag(inode, &di_et, + &ref_tree->rf_ci, + ref_root_bh, cpos, + p_cluster, num_clusters, + &dealloc, NULL); + if (ret) { + mlog_errno(ret); + goto unlock; + } + + data_changed = 1; + } + cpos += num_clusters; + } + + if (oi->ip_dyn_features & OCFS2_HAS_XATTR_FL) { + ret = ocfs2_xattr_attach_refcount_tree(inode, di_bh, + &ref_tree->rf_ci, + ref_root_bh, + &dealloc); + if (ret) { + mlog_errno(ret); + goto unlock; + } + } + + if (data_changed) { + ret = ocfs2_change_ctime(inode, di_bh); + if (ret) + mlog_errno(ret); + } + +unlock: + ocfs2_unlock_refcount_tree(osb, ref_tree, 1); + brelse(ref_root_bh); + + if (!ret && ocfs2_dealloc_has_cluster(&dealloc)) { + ocfs2_schedule_truncate_log_flush(osb, 1); + ocfs2_run_deallocs(osb, &dealloc); + } +out: + /* + * Empty the extent map so that we may get the right extent + * record from the disk. + */ + ocfs2_extent_map_trunc(inode, 0); + + return ret; +} + +static int ocfs2_add_refcounted_extent(struct inode *inode, + struct ocfs2_extent_tree *et, + struct ocfs2_caching_info *ref_ci, + struct buffer_head *ref_root_bh, + u32 cpos, u32 p_cluster, u32 num_clusters, + unsigned int ext_flags, + struct ocfs2_cached_dealloc_ctxt *dealloc) +{ + int ret; + handle_t *handle; + int credits = 0; + struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); + struct ocfs2_alloc_context *meta_ac = NULL; + + ret = ocfs2_lock_refcount_allocators(inode->i_sb, + p_cluster, num_clusters, + et, ref_ci, + ref_root_bh, &meta_ac, + NULL, &credits); + if (ret) { + mlog_errno(ret); + goto out; + } + + handle = ocfs2_start_trans(osb, credits); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + goto out; + } + + ret = ocfs2_insert_extent(handle, et, cpos, + cpu_to_le64(ocfs2_clusters_to_blocks(inode->i_sb, + p_cluster)), + num_clusters, ext_flags, meta_ac); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + + ret = ocfs2_increase_refcount(handle, ref_ci, ref_root_bh, + p_cluster, num_clusters, + meta_ac, dealloc); + if (ret) + mlog_errno(ret); + +out_commit: + ocfs2_commit_trans(osb, handle); +out: + if (meta_ac) + ocfs2_free_alloc_context(meta_ac); + return ret; +} + +static int ocfs2_duplicate_extent_list(struct inode *s_inode, + struct inode *t_inode, + struct buffer_head *t_bh, + struct ocfs2_caching_info *ref_ci, + struct buffer_head *ref_root_bh, + struct ocfs2_cached_dealloc_ctxt *dealloc) +{ + int ret = 0; + u32 p_cluster, num_clusters, clusters, cpos; + loff_t size; + unsigned int ext_flags; + struct ocfs2_extent_tree et; + + ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(t_inode), t_bh); + + size = i_size_read(s_inode); + clusters = ocfs2_clusters_for_bytes(s_inode->i_sb, size); + + cpos = 0; + while (cpos < clusters) { + ret = ocfs2_get_clusters(s_inode, cpos, &p_cluster, + &num_clusters, &ext_flags); + + if (p_cluster) { + ret = ocfs2_add_refcounted_extent(t_inode, &et, + ref_ci, ref_root_bh, + cpos, p_cluster, + num_clusters, + ext_flags, + dealloc); + if (ret) { + mlog_errno(ret); + goto out; + } + } + + cpos += num_clusters; + } + +out: + return ret; +} + +/* + * change the new file's attributes to the src. + * + * reflink creates a snapshot of a file, that means the attributes + * must be identical except for three exceptions - nlink, ino, and ctime. + */ +static int ocfs2_complete_reflink(struct inode *s_inode, + struct buffer_head *s_bh, + struct inode *t_inode, + struct buffer_head *t_bh, + bool preserve) +{ + int ret; + handle_t *handle; + struct ocfs2_dinode *s_di = (struct ocfs2_dinode *)s_bh->b_data; + struct ocfs2_dinode *di = (struct ocfs2_dinode *)t_bh->b_data; + loff_t size = i_size_read(s_inode); + + handle = ocfs2_start_trans(OCFS2_SB(t_inode->i_sb), + OCFS2_INODE_UPDATE_CREDITS); + if (IS_ERR(handle)) { + ret = PTR_ERR(handle); + mlog_errno(ret); + return ret; + } + + ret = ocfs2_journal_access_di(handle, INODE_CACHE(t_inode), t_bh, + OCFS2_JOURNAL_ACCESS_WRITE); + if (ret) { + mlog_errno(ret); + goto out_commit; + } + + spin_lock(&OCFS2_I(t_inode)->ip_lock); + OCFS2_I(t_inode)->ip_clusters = OCFS2_I(s_inode)->ip_clusters; + OCFS2_I(t_inode)->ip_attr = OCFS2_I(s_inode)->ip_attr; + OCFS2_I(t_inode)->ip_dyn_features = OCFS2_I(s_inode)->ip_dyn_features; + spin_unlock(&OCFS2_I(t_inode)->ip_lock); + i_size_write(t_inode, size); + + di->i_xattr_inline_size = s_di->i_xattr_inline_size; + di->i_clusters = s_di->i_clusters; + di->i_size = s_di->i_size; + di->i_dyn_features = s_di->i_dyn_features; + di->i_attr = s_di->i_attr; + + if (preserve) { + di->i_uid = s_di->i_uid; + di->i_gid = s_di->i_gid; + di->i_mode = s_di->i_mode; + + /* + * update time. + * we want mtime to appear identical to the source and + * update ctime. + */ + t_inode->i_ctime = CURRENT_TIME; + + di->i_ctime = cpu_to_le64(t_inode->i_ctime.tv_sec); + di->i_ctime_nsec = cpu_to_le32(t_inode->i_ctime.tv_nsec); + + t_inode->i_mtime = s_inode->i_mtime; + di->i_mtime = s_di->i_mtime; + di->i_mtime_nsec = s_di->i_mtime_nsec; + } + + ocfs2_journal_dirty(handle, t_bh); + +out_commit: + ocfs2_commit_trans(OCFS2_SB(t_inode->i_sb), handle); + return ret; +} + +static int ocfs2_create_reflink_node(struct inode *s_inode, + struct buffer_head *s_bh, + struct inode *t_inode, + struct buffer_head *t_bh, + bool preserve) +{ + int ret; + struct buffer_head *ref_root_bh = NULL; + struct ocfs2_cached_dealloc_ctxt dealloc; + struct ocfs2_super *osb = OCFS2_SB(s_inode->i_sb); + struct ocfs2_refcount_block *rb; + struct ocfs2_dinode *di = (struct ocfs2_dinode *)s_bh->b_data; + struct ocfs2_refcount_tree *ref_tree; + + ocfs2_init_dealloc_ctxt(&dealloc); + + ret = ocfs2_set_refcount_tree(t_inode, t_bh, + le64_to_cpu(di->i_refcount_loc)); + if (ret) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_lock_refcount_tree(osb, le64_to_cpu(di->i_refcount_loc), + 1, &ref_tree, &ref_root_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + rb = (struct ocfs2_refcount_block *)ref_root_bh->b_data; + + ret = ocfs2_duplicate_extent_list(s_inode, t_inode, t_bh, + &ref_tree->rf_ci, ref_root_bh, + &dealloc); + if (ret) { + mlog_errno(ret); + goto out_unlock_refcount; + } + + ret = ocfs2_complete_reflink(s_inode, s_bh, t_inode, t_bh, preserve); + if (ret) + mlog_errno(ret); + +out_unlock_refcount: + ocfs2_unlock_refcount_tree(osb, ref_tree, 1); + brelse(ref_root_bh); +out: + if (ocfs2_dealloc_has_cluster(&dealloc)) { + ocfs2_schedule_truncate_log_flush(osb, 1); + ocfs2_run_deallocs(osb, &dealloc); + } + + return ret; +} + +static int __ocfs2_reflink(struct dentry *old_dentry, + struct buffer_head *old_bh, + struct inode *new_inode, + bool preserve) +{ + int ret; + struct inode *inode = old_dentry->d_inode; + struct buffer_head *new_bh = NULL; + + ret = filemap_fdatawrite(inode->i_mapping); + if (ret) { + mlog_errno(ret); + goto out; + } + + ret = ocfs2_attach_refcount_tree(inode, old_bh); + if (ret) { + mlog_errno(ret); + goto out; + } + + mutex_lock(&new_inode->i_mutex); + ret = ocfs2_inode_lock(new_inode, &new_bh, 1); + if (ret) { + mlog_errno(ret); + goto out_unlock; + } + + ret = ocfs2_create_reflink_node(inode, old_bh, + new_inode, new_bh, preserve); + if (ret) { + mlog_errno(ret); + goto inode_unlock; + } + + if (OCFS2_I(inode)->ip_dyn_features & OCFS2_HAS_XATTR_FL) { + ret = ocfs2_reflink_xattrs(inode, old_bh, + new_inode, new_bh, + preserve); + if (ret) + mlog_errno(ret); + } +inode_unlock: + ocfs2_inode_unlock(new_inode, 1); + brelse(new_bh); +out_unlock: + mutex_unlock(&new_inode->i_mutex); +out: + if (!ret) { + ret = filemap_fdatawait(inode->i_mapping); + if (ret) + mlog_errno(ret); + } + return ret; +} + +static int ocfs2_reflink(struct dentry *old_dentry, struct inode *dir, + struct dentry *new_dentry, bool preserve) +{ + int error; + struct inode *inode = old_dentry->d_inode; + struct buffer_head *old_bh = NULL; + struct inode *new_orphan_inode = NULL; + + if (!ocfs2_refcount_tree(OCFS2_SB(inode->i_sb))) + return -EOPNOTSUPP; + + error = ocfs2_create_inode_in_orphan(dir, inode->i_mode, + &new_orphan_inode); + if (error) { + mlog_errno(error); + goto out; + } + + error = ocfs2_inode_lock(inode, &old_bh, 1); + if (error) { + mlog_errno(error); + goto out; + } + + down_write(&OCFS2_I(inode)->ip_xattr_sem); + down_write(&OCFS2_I(inode)->ip_alloc_sem); + error = __ocfs2_reflink(old_dentry, old_bh, + new_orphan_inode, preserve); + up_write(&OCFS2_I(inode)->ip_alloc_sem); + up_write(&OCFS2_I(inode)->ip_xattr_sem); + + ocfs2_inode_unlock(inode, 1); + brelse(old_bh); + + if (error) { + mlog_errno(error); + goto out; + } + + /* If the security isn't preserved, we need to re-initialize them. */ + if (!preserve) { + error = ocfs2_init_security_and_acl(dir, new_orphan_inode); + if (error) + mlog_errno(error); + } +out: + if (!error) { + error = ocfs2_mv_orphaned_inode_to_new(dir, new_orphan_inode, + new_dentry); + if (error) + mlog_errno(error); + } + + if (new_orphan_inode) { + /* + * We need to open_unlock the inode no matter whether we + * succeed or not, so that other nodes can delete it later. + */ + ocfs2_open_unlock(new_orphan_inode); + if (error) + iput(new_orphan_inode); + } + + return error; +} + +/* + * Below here are the bits used by OCFS2_IOC_REFLINK() to fake + * sys_reflink(). This will go away when vfs_reflink() exists in + * fs/namei.c. + */ + +/* copied from may_create in VFS. */ +static inline int ocfs2_may_create(struct inode *dir, struct dentry *child) +{ + if (child->d_inode) + return -EEXIST; + if (IS_DEADDIR(dir)) + return -ENOENT; + return inode_permission(dir, MAY_WRITE | MAY_EXEC); +} + +/* copied from user_path_parent. */ +static int ocfs2_user_path_parent(const char __user *path, + struct nameidata *nd, char **name) +{ + char *s = getname(path); + int error; + + if (IS_ERR(s)) + return PTR_ERR(s); + + error = path_lookup(s, LOOKUP_PARENT, nd); + if (error) + putname(s); + else + *name = s; + + return error; +} + +/** + * ocfs2_vfs_reflink - Create a reference-counted link + * + * @old_dentry: source dentry + inode + * @dir: directory to create the target + * @new_dentry: target dentry + * @preserve: if true, preserve all file attributes + */ +int ocfs2_vfs_reflink(struct dentry *old_dentry, struct inode *dir, + struct dentry *new_dentry, bool preserve) +{ + struct inode *inode = old_dentry->d_inode; + int error; + + if (!inode) + return -ENOENT; + + error = ocfs2_may_create(dir, new_dentry); + if (error) + return error; + + if (dir->i_sb != inode->i_sb) + return -EXDEV; + + /* + * A reflink to an append-only or immutable file cannot be created. + */ + if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) + return -EPERM; + + /* Only regular files can be reflinked. */ + if (!S_ISREG(inode->i_mode)) + return -EPERM; + + /* + * If the caller wants to preserve ownership, they require the + * rights to do so. + */ + if (preserve) { + if ((current_fsuid() != inode->i_uid) && !capable(CAP_CHOWN)) + return -EPERM; + if (!in_group_p(inode->i_gid) && !capable(CAP_CHOWN)) + return -EPERM; + } + + /* + * If the caller is modifying any aspect of the attributes, they + * are not creating a snapshot. They need read permission on the + * file. + */ + if (!preserve) { + error = inode_permission(inode, MAY_READ); + if (error) + return error; + } + + mutex_lock(&inode->i_mutex); + vfs_dq_init(dir); + error = ocfs2_reflink(old_dentry, dir, new_dentry, preserve); + mutex_unlock(&inode->i_mutex); + if (!error) + fsnotify_create(dir, new_dentry); + return error; +} +/* + * Most codes are copied from sys_linkat. + */ +int ocfs2_reflink_ioctl(struct inode *inode, + const char __user *oldname, + const char __user *newname, + bool preserve) +{ + struct dentry *new_dentry; + struct nameidata nd; + struct path old_path; + int error; + char *to = NULL; + + if (!ocfs2_refcount_tree(OCFS2_SB(inode->i_sb))) + return -EOPNOTSUPP; + + error = user_path_at(AT_FDCWD, oldname, 0, &old_path); + if (error) { + mlog_errno(error); + return error; + } + + error = ocfs2_user_path_parent(newname, &nd, &to); + if (error) { + mlog_errno(error); + goto out; + } + + error = -EXDEV; + if (old_path.mnt != nd.path.mnt) + goto out_release; + new_dentry = lookup_create(&nd, 0); + error = PTR_ERR(new_dentry); + if (IS_ERR(new_dentry)) { + mlog_errno(error); + goto out_unlock; + } + + error = mnt_want_write(nd.path.mnt); + if (error) { + mlog_errno(error); + goto out_dput; + } + + error = ocfs2_vfs_reflink(old_path.dentry, + nd.path.dentry->d_inode, + new_dentry, preserve); + mnt_drop_write(nd.path.mnt); +out_dput: + dput(new_dentry); +out_unlock: + mutex_unlock(&nd.path.dentry->d_inode->i_mutex); +out_release: + path_put(&nd.path); + putname(to); +out: + path_put(&old_path); + + return error; +} |