/* -*- 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 <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>
struct ocfs2_cow_context {
struct inode *inode;
u32 cow_start;
u32 cow_len;
struct ocfs2_extent_tree di_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;
struct ocfs2_cached_dealloc_ctxt dealloc;
};
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;
}
/*
* 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 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
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,
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);
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,
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);
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,
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, 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, 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,
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;
}
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);
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,
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 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\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;
}
r_count = le32_to_cpu(rec.r_refcount);
BUG_ON(r_count == 0);
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) {
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 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);
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.
*
* 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 buffer_head *di_bh,
u32 cpos,
u32 write_len,
u32 *cow_start,
u32 *cow_len)
{
int ret = 0;
struct ocfs2_dinode *di = (struct ocfs2_dinode *) di_bh->b_data;
struct ocfs2_extent_list *el = &di->id2.i_list;
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;
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 or a non-refcounted record,
* stop the search.
*/
if ((!(rec->e_flags & OCFS2_EXT_REFCOUNTED)) ||
(*cow_len && rec_end != 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;
/*
* 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(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->di_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_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->di_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 = ocfs2_duplicate_clusters(handle, context, cpos,
old, new, len);
if (ret) {
mlog_errno(ret);
goto out;
}
}
ret = ocfs2_clear_ext_refcount(handle, &context->di_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_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, credits = 0;
u32 new_bit, new_len;
struct ocfs2_super *osb = OCFS2_SB(sb);
handle_t *handle;
ret = ocfs2_lock_refcount_allocators(sb, p_cluster, num_clusters,
&context->di_et,
context->ref_ci,
context->ref_root_bh,
&context->meta_ac,
&context->data_ac, &credits);
if (ret) {
mlog_errno(ret);
return ret;
}
handle = ocfs2_start_trans(osb, credits);
if (IS_ERR(handle)) {
ret = PTR_ERR(handle);
mlog_errno(ret);
goto out;
}
while (num_clusters) {
ret = __ocfs2_claim_clusters(osb, handle, context->data_ac,
1, num_clusters,
&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;
}
cpos += new_len;
p_cluster += new_len;
num_clusters -= new_len;
}
ret = __ocfs2_decrease_refcount(handle, context->ref_ci,
context->ref_root_bh,
p_cluster, num_clusters,
context->meta_ac,
&context->dealloc);
if (ret) {
mlog_errno(ret);
goto out_commit;
}
/*
* Here we should write the new page out first if we are
* in write-back mode.
*/
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;
}
return ret;
}
static int ocfs2_replace_cow(struct inode *inode,
struct buffer_head *di_bh,
struct buffer_head *ref_root_bh,
struct ocfs2_caching_info *ref_ci,
u32 cow_start, u32 cow_len)
{
int ret = 0;
u32 p_cluster, num_clusters, start = cow_start;
unsigned int ext_flags;
struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
struct ocfs2_cow_context *context;
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;
}
context = kzalloc(sizeof(struct ocfs2_cow_context), GFP_NOFS);
if (!context) {
ret = -ENOMEM;
mlog_errno(ret);
return ret;
}
context->inode = inode;
context->cow_start = cow_start;
context->cow_len = cow_len;
context->ref_ci = ref_ci;
context->ref_root_bh = ref_root_bh;
ocfs2_init_dealloc_ctxt(&context->dealloc);
ocfs2_init_dinode_extent_tree(&context->di_et,
INODE_CACHE(inode), di_bh);
while (cow_len) {
ret = ocfs2_get_clusters(inode, 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;
}
/*
* 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, start);
if (ocfs2_dealloc_has_cluster(&context->dealloc)) {
ocfs2_schedule_truncate_log_flush(osb, 1);
ocfs2_run_deallocs(osb, &context->dealloc);
}
kfree(context);
return ret;
}
/*
* Starting at cpos, try to CoW write_len clusters.
* 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)
{
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;
BUG_ON(!(oi->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL));
ret = ocfs2_refcount_cal_cow_clusters(inode, di_bh, cpos, write_len,
&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);
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;
}
ret = ocfs2_replace_cow(inode, di_bh, ref_root_bh, &ref_tree->rf_ci,
cow_start, cow_len);
if (ret)
mlog_errno(ret);
ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
brelse(ref_root_bh);
out:
return ret;
}
/*
* CoW any and all clusters between cpos and cpos+write_len.
* 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)
{
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);
if (ret) {
mlog_errno(ret);
break;
}
}
write_len -= num_clusters;
cpos += num_clusters;
}
return ret;
}
