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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
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dc7fdde39e
We're spending huge amounts of time on lock contention during end_io processing because we unconditionally assume we are overwriting an existing extent in the file for each IO. This checks to see if we are outside i_size, and if so, it uses a less expensive readonly search of the btree to look for existing extents. Signed-off-by: Chris Mason <chris.mason@oracle.com>
1908 lines
48 KiB
C
1908 lines
48 KiB
C
/*
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* Copyright (C) 2007 Oracle. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public
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* License v2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public
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* License along with this program; if not, write to the
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* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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* Boston, MA 021110-1307, USA.
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*/
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#include <linux/fs.h>
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#include <linux/pagemap.h>
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#include <linux/highmem.h>
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#include <linux/time.h>
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#include <linux/init.h>
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#include <linux/string.h>
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#include <linux/backing-dev.h>
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#include <linux/mpage.h>
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#include <linux/falloc.h>
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#include <linux/swap.h>
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#include <linux/writeback.h>
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#include <linux/statfs.h>
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#include <linux/compat.h>
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#include <linux/slab.h>
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#include "ctree.h"
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#include "disk-io.h"
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#include "transaction.h"
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#include "btrfs_inode.h"
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#include "ioctl.h"
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#include "print-tree.h"
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#include "tree-log.h"
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#include "locking.h"
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#include "compat.h"
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/*
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* when auto defrag is enabled we
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* queue up these defrag structs to remember which
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* inodes need defragging passes
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*/
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struct inode_defrag {
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struct rb_node rb_node;
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/* objectid */
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u64 ino;
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/*
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* transid where the defrag was added, we search for
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* extents newer than this
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*/
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u64 transid;
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/* root objectid */
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u64 root;
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/* last offset we were able to defrag */
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u64 last_offset;
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/* if we've wrapped around back to zero once already */
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int cycled;
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};
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/* pop a record for an inode into the defrag tree. The lock
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* must be held already
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*
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* If you're inserting a record for an older transid than an
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* existing record, the transid already in the tree is lowered
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*
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* If an existing record is found the defrag item you
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* pass in is freed
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*/
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static void __btrfs_add_inode_defrag(struct inode *inode,
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struct inode_defrag *defrag)
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{
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struct btrfs_root *root = BTRFS_I(inode)->root;
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struct inode_defrag *entry;
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struct rb_node **p;
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struct rb_node *parent = NULL;
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p = &root->fs_info->defrag_inodes.rb_node;
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while (*p) {
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parent = *p;
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entry = rb_entry(parent, struct inode_defrag, rb_node);
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if (defrag->ino < entry->ino)
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p = &parent->rb_left;
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else if (defrag->ino > entry->ino)
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p = &parent->rb_right;
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else {
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/* if we're reinserting an entry for
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* an old defrag run, make sure to
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* lower the transid of our existing record
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*/
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if (defrag->transid < entry->transid)
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entry->transid = defrag->transid;
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if (defrag->last_offset > entry->last_offset)
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entry->last_offset = defrag->last_offset;
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goto exists;
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}
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}
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BTRFS_I(inode)->in_defrag = 1;
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rb_link_node(&defrag->rb_node, parent, p);
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rb_insert_color(&defrag->rb_node, &root->fs_info->defrag_inodes);
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return;
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exists:
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kfree(defrag);
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return;
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}
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/*
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* insert a defrag record for this inode if auto defrag is
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* enabled
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*/
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int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans,
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struct inode *inode)
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{
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struct btrfs_root *root = BTRFS_I(inode)->root;
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struct inode_defrag *defrag;
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u64 transid;
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if (!btrfs_test_opt(root, AUTO_DEFRAG))
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return 0;
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if (btrfs_fs_closing(root->fs_info))
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return 0;
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if (BTRFS_I(inode)->in_defrag)
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return 0;
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if (trans)
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transid = trans->transid;
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else
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transid = BTRFS_I(inode)->root->last_trans;
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defrag = kzalloc(sizeof(*defrag), GFP_NOFS);
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if (!defrag)
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return -ENOMEM;
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defrag->ino = btrfs_ino(inode);
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defrag->transid = transid;
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defrag->root = root->root_key.objectid;
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spin_lock(&root->fs_info->defrag_inodes_lock);
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if (!BTRFS_I(inode)->in_defrag)
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__btrfs_add_inode_defrag(inode, defrag);
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else
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kfree(defrag);
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spin_unlock(&root->fs_info->defrag_inodes_lock);
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return 0;
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}
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/*
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* must be called with the defrag_inodes lock held
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*/
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struct inode_defrag *btrfs_find_defrag_inode(struct btrfs_fs_info *info, u64 ino,
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struct rb_node **next)
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{
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struct inode_defrag *entry = NULL;
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struct rb_node *p;
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struct rb_node *parent = NULL;
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p = info->defrag_inodes.rb_node;
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while (p) {
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parent = p;
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entry = rb_entry(parent, struct inode_defrag, rb_node);
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if (ino < entry->ino)
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p = parent->rb_left;
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else if (ino > entry->ino)
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p = parent->rb_right;
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else
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return entry;
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}
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if (next) {
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while (parent && ino > entry->ino) {
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parent = rb_next(parent);
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entry = rb_entry(parent, struct inode_defrag, rb_node);
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}
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*next = parent;
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}
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return NULL;
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}
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/*
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* run through the list of inodes in the FS that need
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* defragging
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*/
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int btrfs_run_defrag_inodes(struct btrfs_fs_info *fs_info)
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{
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struct inode_defrag *defrag;
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struct btrfs_root *inode_root;
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struct inode *inode;
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struct rb_node *n;
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struct btrfs_key key;
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struct btrfs_ioctl_defrag_range_args range;
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u64 first_ino = 0;
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int num_defrag;
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int defrag_batch = 1024;
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memset(&range, 0, sizeof(range));
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range.len = (u64)-1;
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atomic_inc(&fs_info->defrag_running);
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spin_lock(&fs_info->defrag_inodes_lock);
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while(1) {
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n = NULL;
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/* find an inode to defrag */
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defrag = btrfs_find_defrag_inode(fs_info, first_ino, &n);
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if (!defrag) {
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if (n)
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defrag = rb_entry(n, struct inode_defrag, rb_node);
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else if (first_ino) {
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first_ino = 0;
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continue;
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} else {
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break;
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}
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}
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/* remove it from the rbtree */
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first_ino = defrag->ino + 1;
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rb_erase(&defrag->rb_node, &fs_info->defrag_inodes);
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if (btrfs_fs_closing(fs_info))
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goto next_free;
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spin_unlock(&fs_info->defrag_inodes_lock);
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/* get the inode */
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key.objectid = defrag->root;
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btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
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key.offset = (u64)-1;
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inode_root = btrfs_read_fs_root_no_name(fs_info, &key);
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if (IS_ERR(inode_root))
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goto next;
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key.objectid = defrag->ino;
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btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
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key.offset = 0;
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inode = btrfs_iget(fs_info->sb, &key, inode_root, NULL);
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if (IS_ERR(inode))
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goto next;
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/* do a chunk of defrag */
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BTRFS_I(inode)->in_defrag = 0;
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range.start = defrag->last_offset;
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num_defrag = btrfs_defrag_file(inode, NULL, &range, defrag->transid,
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defrag_batch);
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/*
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* if we filled the whole defrag batch, there
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* must be more work to do. Queue this defrag
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* again
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*/
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if (num_defrag == defrag_batch) {
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defrag->last_offset = range.start;
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__btrfs_add_inode_defrag(inode, defrag);
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/*
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* we don't want to kfree defrag, we added it back to
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* the rbtree
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*/
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defrag = NULL;
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} else if (defrag->last_offset && !defrag->cycled) {
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/*
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* we didn't fill our defrag batch, but
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* we didn't start at zero. Make sure we loop
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* around to the start of the file.
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*/
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defrag->last_offset = 0;
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defrag->cycled = 1;
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__btrfs_add_inode_defrag(inode, defrag);
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defrag = NULL;
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}
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iput(inode);
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next:
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spin_lock(&fs_info->defrag_inodes_lock);
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next_free:
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kfree(defrag);
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}
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spin_unlock(&fs_info->defrag_inodes_lock);
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atomic_dec(&fs_info->defrag_running);
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/*
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* during unmount, we use the transaction_wait queue to
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* wait for the defragger to stop
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*/
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wake_up(&fs_info->transaction_wait);
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return 0;
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}
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/* simple helper to fault in pages and copy. This should go away
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* and be replaced with calls into generic code.
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*/
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static noinline int btrfs_copy_from_user(loff_t pos, int num_pages,
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size_t write_bytes,
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struct page **prepared_pages,
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struct iov_iter *i)
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{
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size_t copied = 0;
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size_t total_copied = 0;
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int pg = 0;
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int offset = pos & (PAGE_CACHE_SIZE - 1);
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while (write_bytes > 0) {
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size_t count = min_t(size_t,
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PAGE_CACHE_SIZE - offset, write_bytes);
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struct page *page = prepared_pages[pg];
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/*
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* Copy data from userspace to the current page
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*
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* Disable pagefault to avoid recursive lock since
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* the pages are already locked
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*/
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pagefault_disable();
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copied = iov_iter_copy_from_user_atomic(page, i, offset, count);
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pagefault_enable();
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/* Flush processor's dcache for this page */
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flush_dcache_page(page);
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/*
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* if we get a partial write, we can end up with
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* partially up to date pages. These add
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* a lot of complexity, so make sure they don't
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* happen by forcing this copy to be retried.
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*
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* The rest of the btrfs_file_write code will fall
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* back to page at a time copies after we return 0.
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*/
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if (!PageUptodate(page) && copied < count)
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copied = 0;
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iov_iter_advance(i, copied);
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write_bytes -= copied;
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total_copied += copied;
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/* Return to btrfs_file_aio_write to fault page */
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if (unlikely(copied == 0))
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break;
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if (unlikely(copied < PAGE_CACHE_SIZE - offset)) {
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offset += copied;
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} else {
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pg++;
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offset = 0;
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}
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}
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return total_copied;
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}
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/*
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* unlocks pages after btrfs_file_write is done with them
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*/
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void btrfs_drop_pages(struct page **pages, size_t num_pages)
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{
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size_t i;
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for (i = 0; i < num_pages; i++) {
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/* page checked is some magic around finding pages that
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* have been modified without going through btrfs_set_page_dirty
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* clear it here
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*/
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ClearPageChecked(pages[i]);
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unlock_page(pages[i]);
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mark_page_accessed(pages[i]);
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page_cache_release(pages[i]);
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}
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}
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/*
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* after copy_from_user, pages need to be dirtied and we need to make
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* sure holes are created between the current EOF and the start of
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* any next extents (if required).
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*
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* this also makes the decision about creating an inline extent vs
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* doing real data extents, marking pages dirty and delalloc as required.
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*/
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int btrfs_dirty_pages(struct btrfs_root *root, struct inode *inode,
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struct page **pages, size_t num_pages,
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loff_t pos, size_t write_bytes,
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struct extent_state **cached)
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{
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int err = 0;
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int i;
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u64 num_bytes;
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u64 start_pos;
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u64 end_of_last_block;
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u64 end_pos = pos + write_bytes;
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loff_t isize = i_size_read(inode);
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start_pos = pos & ~((u64)root->sectorsize - 1);
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num_bytes = (write_bytes + pos - start_pos +
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root->sectorsize - 1) & ~((u64)root->sectorsize - 1);
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end_of_last_block = start_pos + num_bytes - 1;
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err = btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block,
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cached);
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if (err)
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return err;
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for (i = 0; i < num_pages; i++) {
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struct page *p = pages[i];
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SetPageUptodate(p);
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ClearPageChecked(p);
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set_page_dirty(p);
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}
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/*
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* we've only changed i_size in ram, and we haven't updated
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* the disk i_size. There is no need to log the inode
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* at this time.
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*/
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if (end_pos > isize)
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i_size_write(inode, end_pos);
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return 0;
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}
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/*
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* this drops all the extents in the cache that intersect the range
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* [start, end]. Existing extents are split as required.
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*/
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int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end,
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int skip_pinned)
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{
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struct extent_map *em;
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struct extent_map *split = NULL;
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struct extent_map *split2 = NULL;
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struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
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u64 len = end - start + 1;
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int ret;
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int testend = 1;
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unsigned long flags;
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int compressed = 0;
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WARN_ON(end < start);
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if (end == (u64)-1) {
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len = (u64)-1;
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testend = 0;
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}
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while (1) {
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if (!split)
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split = alloc_extent_map();
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if (!split2)
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split2 = alloc_extent_map();
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BUG_ON(!split || !split2); /* -ENOMEM */
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write_lock(&em_tree->lock);
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em = lookup_extent_mapping(em_tree, start, len);
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if (!em) {
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write_unlock(&em_tree->lock);
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break;
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}
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flags = em->flags;
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if (skip_pinned && test_bit(EXTENT_FLAG_PINNED, &em->flags)) {
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if (testend && em->start + em->len >= start + len) {
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free_extent_map(em);
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write_unlock(&em_tree->lock);
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break;
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}
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start = em->start + em->len;
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if (testend)
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len = start + len - (em->start + em->len);
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free_extent_map(em);
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write_unlock(&em_tree->lock);
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continue;
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}
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compressed = test_bit(EXTENT_FLAG_COMPRESSED, &em->flags);
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clear_bit(EXTENT_FLAG_PINNED, &em->flags);
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remove_extent_mapping(em_tree, em);
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|
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if (em->block_start < EXTENT_MAP_LAST_BYTE &&
|
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em->start < start) {
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split->start = em->start;
|
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split->len = start - em->start;
|
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split->orig_start = em->orig_start;
|
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split->block_start = em->block_start;
|
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|
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if (compressed)
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split->block_len = em->block_len;
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else
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split->block_len = split->len;
|
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|
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split->bdev = em->bdev;
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split->flags = flags;
|
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split->compress_type = em->compress_type;
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ret = add_extent_mapping(em_tree, split);
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BUG_ON(ret); /* Logic error */
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free_extent_map(split);
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split = split2;
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split2 = NULL;
|
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}
|
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if (em->block_start < EXTENT_MAP_LAST_BYTE &&
|
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testend && em->start + em->len > start + len) {
|
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u64 diff = start + len - em->start;
|
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|
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split->start = start + len;
|
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split->len = em->start + em->len - (start + len);
|
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split->bdev = em->bdev;
|
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split->flags = flags;
|
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split->compress_type = em->compress_type;
|
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|
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if (compressed) {
|
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split->block_len = em->block_len;
|
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split->block_start = em->block_start;
|
|
split->orig_start = em->orig_start;
|
|
} else {
|
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split->block_len = split->len;
|
|
split->block_start = em->block_start + diff;
|
|
split->orig_start = split->start;
|
|
}
|
|
|
|
ret = add_extent_mapping(em_tree, split);
|
|
BUG_ON(ret); /* Logic error */
|
|
free_extent_map(split);
|
|
split = NULL;
|
|
}
|
|
write_unlock(&em_tree->lock);
|
|
|
|
/* once for us */
|
|
free_extent_map(em);
|
|
/* once for the tree*/
|
|
free_extent_map(em);
|
|
}
|
|
if (split)
|
|
free_extent_map(split);
|
|
if (split2)
|
|
free_extent_map(split2);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* this is very complex, but the basic idea is to drop all extents
|
|
* in the range start - end. hint_block is filled in with a block number
|
|
* that would be a good hint to the block allocator for this file.
|
|
*
|
|
* If an extent intersects the range but is not entirely inside the range
|
|
* it is either truncated or split. Anything entirely inside the range
|
|
* is deleted from the tree.
|
|
*/
|
|
int btrfs_drop_extents(struct btrfs_trans_handle *trans, struct inode *inode,
|
|
u64 start, u64 end, u64 *hint_byte, int drop_cache)
|
|
{
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
struct extent_buffer *leaf;
|
|
struct btrfs_file_extent_item *fi;
|
|
struct btrfs_path *path;
|
|
struct btrfs_key key;
|
|
struct btrfs_key new_key;
|
|
u64 ino = btrfs_ino(inode);
|
|
u64 search_start = start;
|
|
u64 disk_bytenr = 0;
|
|
u64 num_bytes = 0;
|
|
u64 extent_offset = 0;
|
|
u64 extent_end = 0;
|
|
int del_nr = 0;
|
|
int del_slot = 0;
|
|
int extent_type;
|
|
int recow;
|
|
int ret;
|
|
int modify_tree = -1;
|
|
|
|
if (drop_cache)
|
|
btrfs_drop_extent_cache(inode, start, end - 1, 0);
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path)
|
|
return -ENOMEM;
|
|
|
|
if (start >= BTRFS_I(inode)->disk_i_size)
|
|
modify_tree = 0;
|
|
|
|
while (1) {
|
|
recow = 0;
|
|
ret = btrfs_lookup_file_extent(trans, root, path, ino,
|
|
search_start, modify_tree);
|
|
if (ret < 0)
|
|
break;
|
|
if (ret > 0 && path->slots[0] > 0 && search_start == start) {
|
|
leaf = path->nodes[0];
|
|
btrfs_item_key_to_cpu(leaf, &key, path->slots[0] - 1);
|
|
if (key.objectid == ino &&
|
|
key.type == BTRFS_EXTENT_DATA_KEY)
|
|
path->slots[0]--;
|
|
}
|
|
ret = 0;
|
|
next_slot:
|
|
leaf = path->nodes[0];
|
|
if (path->slots[0] >= btrfs_header_nritems(leaf)) {
|
|
BUG_ON(del_nr > 0);
|
|
ret = btrfs_next_leaf(root, path);
|
|
if (ret < 0)
|
|
break;
|
|
if (ret > 0) {
|
|
ret = 0;
|
|
break;
|
|
}
|
|
leaf = path->nodes[0];
|
|
recow = 1;
|
|
}
|
|
|
|
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
|
|
if (key.objectid > ino ||
|
|
key.type > BTRFS_EXTENT_DATA_KEY || key.offset >= end)
|
|
break;
|
|
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
extent_type = btrfs_file_extent_type(leaf, fi);
|
|
|
|
if (extent_type == BTRFS_FILE_EXTENT_REG ||
|
|
extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
|
|
disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
|
|
num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
|
|
extent_offset = btrfs_file_extent_offset(leaf, fi);
|
|
extent_end = key.offset +
|
|
btrfs_file_extent_num_bytes(leaf, fi);
|
|
} else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
|
|
extent_end = key.offset +
|
|
btrfs_file_extent_inline_len(leaf, fi);
|
|
} else {
|
|
WARN_ON(1);
|
|
extent_end = search_start;
|
|
}
|
|
|
|
if (extent_end <= search_start) {
|
|
path->slots[0]++;
|
|
goto next_slot;
|
|
}
|
|
|
|
search_start = max(key.offset, start);
|
|
if (recow || !modify_tree) {
|
|
modify_tree = -1;
|
|
btrfs_release_path(path);
|
|
continue;
|
|
}
|
|
|
|
/*
|
|
* | - range to drop - |
|
|
* | -------- extent -------- |
|
|
*/
|
|
if (start > key.offset && end < extent_end) {
|
|
BUG_ON(del_nr > 0);
|
|
BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE);
|
|
|
|
memcpy(&new_key, &key, sizeof(new_key));
|
|
new_key.offset = start;
|
|
ret = btrfs_duplicate_item(trans, root, path,
|
|
&new_key);
|
|
if (ret == -EAGAIN) {
|
|
btrfs_release_path(path);
|
|
continue;
|
|
}
|
|
if (ret < 0)
|
|
break;
|
|
|
|
leaf = path->nodes[0];
|
|
fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
start - key.offset);
|
|
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
|
|
extent_offset += start - key.offset;
|
|
btrfs_set_file_extent_offset(leaf, fi, extent_offset);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
extent_end - start);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
|
|
if (disk_bytenr > 0) {
|
|
ret = btrfs_inc_extent_ref(trans, root,
|
|
disk_bytenr, num_bytes, 0,
|
|
root->root_key.objectid,
|
|
new_key.objectid,
|
|
start - extent_offset, 0);
|
|
BUG_ON(ret); /* -ENOMEM */
|
|
*hint_byte = disk_bytenr;
|
|
}
|
|
key.offset = start;
|
|
}
|
|
/*
|
|
* | ---- range to drop ----- |
|
|
* | -------- extent -------- |
|
|
*/
|
|
if (start <= key.offset && end < extent_end) {
|
|
BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE);
|
|
|
|
memcpy(&new_key, &key, sizeof(new_key));
|
|
new_key.offset = end;
|
|
btrfs_set_item_key_safe(trans, root, path, &new_key);
|
|
|
|
extent_offset += end - key.offset;
|
|
btrfs_set_file_extent_offset(leaf, fi, extent_offset);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
extent_end - end);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
if (disk_bytenr > 0) {
|
|
inode_sub_bytes(inode, end - key.offset);
|
|
*hint_byte = disk_bytenr;
|
|
}
|
|
break;
|
|
}
|
|
|
|
search_start = extent_end;
|
|
/*
|
|
* | ---- range to drop ----- |
|
|
* | -------- extent -------- |
|
|
*/
|
|
if (start > key.offset && end >= extent_end) {
|
|
BUG_ON(del_nr > 0);
|
|
BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE);
|
|
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
start - key.offset);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
if (disk_bytenr > 0) {
|
|
inode_sub_bytes(inode, extent_end - start);
|
|
*hint_byte = disk_bytenr;
|
|
}
|
|
if (end == extent_end)
|
|
break;
|
|
|
|
path->slots[0]++;
|
|
goto next_slot;
|
|
}
|
|
|
|
/*
|
|
* | ---- range to drop ----- |
|
|
* | ------ extent ------ |
|
|
*/
|
|
if (start <= key.offset && end >= extent_end) {
|
|
if (del_nr == 0) {
|
|
del_slot = path->slots[0];
|
|
del_nr = 1;
|
|
} else {
|
|
BUG_ON(del_slot + del_nr != path->slots[0]);
|
|
del_nr++;
|
|
}
|
|
|
|
if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
|
|
inode_sub_bytes(inode,
|
|
extent_end - key.offset);
|
|
extent_end = ALIGN(extent_end,
|
|
root->sectorsize);
|
|
} else if (disk_bytenr > 0) {
|
|
ret = btrfs_free_extent(trans, root,
|
|
disk_bytenr, num_bytes, 0,
|
|
root->root_key.objectid,
|
|
key.objectid, key.offset -
|
|
extent_offset, 0);
|
|
BUG_ON(ret); /* -ENOMEM */
|
|
inode_sub_bytes(inode,
|
|
extent_end - key.offset);
|
|
*hint_byte = disk_bytenr;
|
|
}
|
|
|
|
if (end == extent_end)
|
|
break;
|
|
|
|
if (path->slots[0] + 1 < btrfs_header_nritems(leaf)) {
|
|
path->slots[0]++;
|
|
goto next_slot;
|
|
}
|
|
|
|
ret = btrfs_del_items(trans, root, path, del_slot,
|
|
del_nr);
|
|
if (ret) {
|
|
btrfs_abort_transaction(trans, root, ret);
|
|
goto out;
|
|
}
|
|
|
|
del_nr = 0;
|
|
del_slot = 0;
|
|
|
|
btrfs_release_path(path);
|
|
continue;
|
|
}
|
|
|
|
BUG_ON(1);
|
|
}
|
|
|
|
if (!ret && del_nr > 0) {
|
|
ret = btrfs_del_items(trans, root, path, del_slot, del_nr);
|
|
if (ret)
|
|
btrfs_abort_transaction(trans, root, ret);
|
|
}
|
|
|
|
out:
|
|
btrfs_free_path(path);
|
|
return ret;
|
|
}
|
|
|
|
static int extent_mergeable(struct extent_buffer *leaf, int slot,
|
|
u64 objectid, u64 bytenr, u64 orig_offset,
|
|
u64 *start, u64 *end)
|
|
{
|
|
struct btrfs_file_extent_item *fi;
|
|
struct btrfs_key key;
|
|
u64 extent_end;
|
|
|
|
if (slot < 0 || slot >= btrfs_header_nritems(leaf))
|
|
return 0;
|
|
|
|
btrfs_item_key_to_cpu(leaf, &key, slot);
|
|
if (key.objectid != objectid || key.type != BTRFS_EXTENT_DATA_KEY)
|
|
return 0;
|
|
|
|
fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item);
|
|
if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG ||
|
|
btrfs_file_extent_disk_bytenr(leaf, fi) != bytenr ||
|
|
btrfs_file_extent_offset(leaf, fi) != key.offset - orig_offset ||
|
|
btrfs_file_extent_compression(leaf, fi) ||
|
|
btrfs_file_extent_encryption(leaf, fi) ||
|
|
btrfs_file_extent_other_encoding(leaf, fi))
|
|
return 0;
|
|
|
|
extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
|
|
if ((*start && *start != key.offset) || (*end && *end != extent_end))
|
|
return 0;
|
|
|
|
*start = key.offset;
|
|
*end = extent_end;
|
|
return 1;
|
|
}
|
|
|
|
/*
|
|
* Mark extent in the range start - end as written.
|
|
*
|
|
* This changes extent type from 'pre-allocated' to 'regular'. If only
|
|
* part of extent is marked as written, the extent will be split into
|
|
* two or three.
|
|
*/
|
|
int btrfs_mark_extent_written(struct btrfs_trans_handle *trans,
|
|
struct inode *inode, u64 start, u64 end)
|
|
{
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
struct extent_buffer *leaf;
|
|
struct btrfs_path *path;
|
|
struct btrfs_file_extent_item *fi;
|
|
struct btrfs_key key;
|
|
struct btrfs_key new_key;
|
|
u64 bytenr;
|
|
u64 num_bytes;
|
|
u64 extent_end;
|
|
u64 orig_offset;
|
|
u64 other_start;
|
|
u64 other_end;
|
|
u64 split;
|
|
int del_nr = 0;
|
|
int del_slot = 0;
|
|
int recow;
|
|
int ret;
|
|
u64 ino = btrfs_ino(inode);
|
|
|
|
btrfs_drop_extent_cache(inode, start, end - 1, 0);
|
|
|
|
path = btrfs_alloc_path();
|
|
if (!path)
|
|
return -ENOMEM;
|
|
again:
|
|
recow = 0;
|
|
split = start;
|
|
key.objectid = ino;
|
|
key.type = BTRFS_EXTENT_DATA_KEY;
|
|
key.offset = split;
|
|
|
|
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
|
|
if (ret < 0)
|
|
goto out;
|
|
if (ret > 0 && path->slots[0] > 0)
|
|
path->slots[0]--;
|
|
|
|
leaf = path->nodes[0];
|
|
btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
|
|
BUG_ON(key.objectid != ino || key.type != BTRFS_EXTENT_DATA_KEY);
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
BUG_ON(btrfs_file_extent_type(leaf, fi) !=
|
|
BTRFS_FILE_EXTENT_PREALLOC);
|
|
extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi);
|
|
BUG_ON(key.offset > start || extent_end < end);
|
|
|
|
bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
|
|
num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
|
|
orig_offset = key.offset - btrfs_file_extent_offset(leaf, fi);
|
|
memcpy(&new_key, &key, sizeof(new_key));
|
|
|
|
if (start == key.offset && end < extent_end) {
|
|
other_start = 0;
|
|
other_end = start;
|
|
if (extent_mergeable(leaf, path->slots[0] - 1,
|
|
ino, bytenr, orig_offset,
|
|
&other_start, &other_end)) {
|
|
new_key.offset = end;
|
|
btrfs_set_item_key_safe(trans, root, path, &new_key);
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
extent_end - end);
|
|
btrfs_set_file_extent_offset(leaf, fi,
|
|
end - orig_offset);
|
|
fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
end - other_start);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (start > key.offset && end == extent_end) {
|
|
other_start = end;
|
|
other_end = 0;
|
|
if (extent_mergeable(leaf, path->slots[0] + 1,
|
|
ino, bytenr, orig_offset,
|
|
&other_start, &other_end)) {
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
start - key.offset);
|
|
path->slots[0]++;
|
|
new_key.offset = start;
|
|
btrfs_set_item_key_safe(trans, root, path, &new_key);
|
|
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
other_end - start);
|
|
btrfs_set_file_extent_offset(leaf, fi,
|
|
start - orig_offset);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
while (start > key.offset || end < extent_end) {
|
|
if (key.offset == start)
|
|
split = end;
|
|
|
|
new_key.offset = split;
|
|
ret = btrfs_duplicate_item(trans, root, path, &new_key);
|
|
if (ret == -EAGAIN) {
|
|
btrfs_release_path(path);
|
|
goto again;
|
|
}
|
|
if (ret < 0) {
|
|
btrfs_abort_transaction(trans, root, ret);
|
|
goto out;
|
|
}
|
|
|
|
leaf = path->nodes[0];
|
|
fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
split - key.offset);
|
|
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
|
|
btrfs_set_file_extent_offset(leaf, fi, split - orig_offset);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
extent_end - split);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
|
|
ret = btrfs_inc_extent_ref(trans, root, bytenr, num_bytes, 0,
|
|
root->root_key.objectid,
|
|
ino, orig_offset, 0);
|
|
BUG_ON(ret); /* -ENOMEM */
|
|
|
|
if (split == start) {
|
|
key.offset = start;
|
|
} else {
|
|
BUG_ON(start != key.offset);
|
|
path->slots[0]--;
|
|
extent_end = end;
|
|
}
|
|
recow = 1;
|
|
}
|
|
|
|
other_start = end;
|
|
other_end = 0;
|
|
if (extent_mergeable(leaf, path->slots[0] + 1,
|
|
ino, bytenr, orig_offset,
|
|
&other_start, &other_end)) {
|
|
if (recow) {
|
|
btrfs_release_path(path);
|
|
goto again;
|
|
}
|
|
extent_end = other_end;
|
|
del_slot = path->slots[0] + 1;
|
|
del_nr++;
|
|
ret = btrfs_free_extent(trans, root, bytenr, num_bytes,
|
|
0, root->root_key.objectid,
|
|
ino, orig_offset, 0);
|
|
BUG_ON(ret); /* -ENOMEM */
|
|
}
|
|
other_start = 0;
|
|
other_end = start;
|
|
if (extent_mergeable(leaf, path->slots[0] - 1,
|
|
ino, bytenr, orig_offset,
|
|
&other_start, &other_end)) {
|
|
if (recow) {
|
|
btrfs_release_path(path);
|
|
goto again;
|
|
}
|
|
key.offset = other_start;
|
|
del_slot = path->slots[0];
|
|
del_nr++;
|
|
ret = btrfs_free_extent(trans, root, bytenr, num_bytes,
|
|
0, root->root_key.objectid,
|
|
ino, orig_offset, 0);
|
|
BUG_ON(ret); /* -ENOMEM */
|
|
}
|
|
if (del_nr == 0) {
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_type(leaf, fi,
|
|
BTRFS_FILE_EXTENT_REG);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
} else {
|
|
fi = btrfs_item_ptr(leaf, del_slot - 1,
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_type(leaf, fi,
|
|
BTRFS_FILE_EXTENT_REG);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
extent_end - key.offset);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
|
|
ret = btrfs_del_items(trans, root, path, del_slot, del_nr);
|
|
if (ret < 0) {
|
|
btrfs_abort_transaction(trans, root, ret);
|
|
goto out;
|
|
}
|
|
}
|
|
out:
|
|
btrfs_free_path(path);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* on error we return an unlocked page and the error value
|
|
* on success we return a locked page and 0
|
|
*/
|
|
static int prepare_uptodate_page(struct page *page, u64 pos,
|
|
bool force_uptodate)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (((pos & (PAGE_CACHE_SIZE - 1)) || force_uptodate) &&
|
|
!PageUptodate(page)) {
|
|
ret = btrfs_readpage(NULL, page);
|
|
if (ret)
|
|
return ret;
|
|
lock_page(page);
|
|
if (!PageUptodate(page)) {
|
|
unlock_page(page);
|
|
return -EIO;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* this gets pages into the page cache and locks them down, it also properly
|
|
* waits for data=ordered extents to finish before allowing the pages to be
|
|
* modified.
|
|
*/
|
|
static noinline int prepare_pages(struct btrfs_root *root, struct file *file,
|
|
struct page **pages, size_t num_pages,
|
|
loff_t pos, unsigned long first_index,
|
|
size_t write_bytes, bool force_uptodate)
|
|
{
|
|
struct extent_state *cached_state = NULL;
|
|
int i;
|
|
unsigned long index = pos >> PAGE_CACHE_SHIFT;
|
|
struct inode *inode = fdentry(file)->d_inode;
|
|
gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
|
|
int err = 0;
|
|
int faili = 0;
|
|
u64 start_pos;
|
|
u64 last_pos;
|
|
|
|
start_pos = pos & ~((u64)root->sectorsize - 1);
|
|
last_pos = ((u64)index + num_pages) << PAGE_CACHE_SHIFT;
|
|
|
|
again:
|
|
for (i = 0; i < num_pages; i++) {
|
|
pages[i] = find_or_create_page(inode->i_mapping, index + i,
|
|
mask | __GFP_WRITE);
|
|
if (!pages[i]) {
|
|
faili = i - 1;
|
|
err = -ENOMEM;
|
|
goto fail;
|
|
}
|
|
|
|
if (i == 0)
|
|
err = prepare_uptodate_page(pages[i], pos,
|
|
force_uptodate);
|
|
if (i == num_pages - 1)
|
|
err = prepare_uptodate_page(pages[i],
|
|
pos + write_bytes, false);
|
|
if (err) {
|
|
page_cache_release(pages[i]);
|
|
faili = i - 1;
|
|
goto fail;
|
|
}
|
|
wait_on_page_writeback(pages[i]);
|
|
}
|
|
err = 0;
|
|
if (start_pos < inode->i_size) {
|
|
struct btrfs_ordered_extent *ordered;
|
|
lock_extent_bits(&BTRFS_I(inode)->io_tree,
|
|
start_pos, last_pos - 1, 0, &cached_state);
|
|
ordered = btrfs_lookup_first_ordered_extent(inode,
|
|
last_pos - 1);
|
|
if (ordered &&
|
|
ordered->file_offset + ordered->len > start_pos &&
|
|
ordered->file_offset < last_pos) {
|
|
btrfs_put_ordered_extent(ordered);
|
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree,
|
|
start_pos, last_pos - 1,
|
|
&cached_state, GFP_NOFS);
|
|
for (i = 0; i < num_pages; i++) {
|
|
unlock_page(pages[i]);
|
|
page_cache_release(pages[i]);
|
|
}
|
|
btrfs_wait_ordered_range(inode, start_pos,
|
|
last_pos - start_pos);
|
|
goto again;
|
|
}
|
|
if (ordered)
|
|
btrfs_put_ordered_extent(ordered);
|
|
|
|
clear_extent_bit(&BTRFS_I(inode)->io_tree, start_pos,
|
|
last_pos - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
|
|
EXTENT_DO_ACCOUNTING, 0, 0, &cached_state,
|
|
GFP_NOFS);
|
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree,
|
|
start_pos, last_pos - 1, &cached_state,
|
|
GFP_NOFS);
|
|
}
|
|
for (i = 0; i < num_pages; i++) {
|
|
if (clear_page_dirty_for_io(pages[i]))
|
|
account_page_redirty(pages[i]);
|
|
set_page_extent_mapped(pages[i]);
|
|
WARN_ON(!PageLocked(pages[i]));
|
|
}
|
|
return 0;
|
|
fail:
|
|
while (faili >= 0) {
|
|
unlock_page(pages[faili]);
|
|
page_cache_release(pages[faili]);
|
|
faili--;
|
|
}
|
|
return err;
|
|
|
|
}
|
|
|
|
static noinline ssize_t __btrfs_buffered_write(struct file *file,
|
|
struct iov_iter *i,
|
|
loff_t pos)
|
|
{
|
|
struct inode *inode = fdentry(file)->d_inode;
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
struct page **pages = NULL;
|
|
unsigned long first_index;
|
|
size_t num_written = 0;
|
|
int nrptrs;
|
|
int ret = 0;
|
|
bool force_page_uptodate = false;
|
|
|
|
nrptrs = min((iov_iter_count(i) + PAGE_CACHE_SIZE - 1) /
|
|
PAGE_CACHE_SIZE, PAGE_CACHE_SIZE /
|
|
(sizeof(struct page *)));
|
|
nrptrs = min(nrptrs, current->nr_dirtied_pause - current->nr_dirtied);
|
|
nrptrs = max(nrptrs, 8);
|
|
pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);
|
|
if (!pages)
|
|
return -ENOMEM;
|
|
|
|
first_index = pos >> PAGE_CACHE_SHIFT;
|
|
|
|
while (iov_iter_count(i) > 0) {
|
|
size_t offset = pos & (PAGE_CACHE_SIZE - 1);
|
|
size_t write_bytes = min(iov_iter_count(i),
|
|
nrptrs * (size_t)PAGE_CACHE_SIZE -
|
|
offset);
|
|
size_t num_pages = (write_bytes + offset +
|
|
PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
|
|
size_t dirty_pages;
|
|
size_t copied;
|
|
|
|
WARN_ON(num_pages > nrptrs);
|
|
|
|
/*
|
|
* Fault pages before locking them in prepare_pages
|
|
* to avoid recursive lock
|
|
*/
|
|
if (unlikely(iov_iter_fault_in_readable(i, write_bytes))) {
|
|
ret = -EFAULT;
|
|
break;
|
|
}
|
|
|
|
ret = btrfs_delalloc_reserve_space(inode,
|
|
num_pages << PAGE_CACHE_SHIFT);
|
|
if (ret)
|
|
break;
|
|
|
|
/*
|
|
* This is going to setup the pages array with the number of
|
|
* pages we want, so we don't really need to worry about the
|
|
* contents of pages from loop to loop
|
|
*/
|
|
ret = prepare_pages(root, file, pages, num_pages,
|
|
pos, first_index, write_bytes,
|
|
force_page_uptodate);
|
|
if (ret) {
|
|
btrfs_delalloc_release_space(inode,
|
|
num_pages << PAGE_CACHE_SHIFT);
|
|
break;
|
|
}
|
|
|
|
copied = btrfs_copy_from_user(pos, num_pages,
|
|
write_bytes, pages, i);
|
|
|
|
/*
|
|
* if we have trouble faulting in the pages, fall
|
|
* back to one page at a time
|
|
*/
|
|
if (copied < write_bytes)
|
|
nrptrs = 1;
|
|
|
|
if (copied == 0) {
|
|
force_page_uptodate = true;
|
|
dirty_pages = 0;
|
|
} else {
|
|
force_page_uptodate = false;
|
|
dirty_pages = (copied + offset +
|
|
PAGE_CACHE_SIZE - 1) >>
|
|
PAGE_CACHE_SHIFT;
|
|
}
|
|
|
|
/*
|
|
* If we had a short copy we need to release the excess delaloc
|
|
* bytes we reserved. We need to increment outstanding_extents
|
|
* because btrfs_delalloc_release_space will decrement it, but
|
|
* we still have an outstanding extent for the chunk we actually
|
|
* managed to copy.
|
|
*/
|
|
if (num_pages > dirty_pages) {
|
|
if (copied > 0) {
|
|
spin_lock(&BTRFS_I(inode)->lock);
|
|
BTRFS_I(inode)->outstanding_extents++;
|
|
spin_unlock(&BTRFS_I(inode)->lock);
|
|
}
|
|
btrfs_delalloc_release_space(inode,
|
|
(num_pages - dirty_pages) <<
|
|
PAGE_CACHE_SHIFT);
|
|
}
|
|
|
|
if (copied > 0) {
|
|
ret = btrfs_dirty_pages(root, inode, pages,
|
|
dirty_pages, pos, copied,
|
|
NULL);
|
|
if (ret) {
|
|
btrfs_delalloc_release_space(inode,
|
|
dirty_pages << PAGE_CACHE_SHIFT);
|
|
btrfs_drop_pages(pages, num_pages);
|
|
break;
|
|
}
|
|
}
|
|
|
|
btrfs_drop_pages(pages, num_pages);
|
|
|
|
cond_resched();
|
|
|
|
balance_dirty_pages_ratelimited_nr(inode->i_mapping,
|
|
dirty_pages);
|
|
if (dirty_pages < (root->leafsize >> PAGE_CACHE_SHIFT) + 1)
|
|
btrfs_btree_balance_dirty(root, 1);
|
|
|
|
pos += copied;
|
|
num_written += copied;
|
|
}
|
|
|
|
kfree(pages);
|
|
|
|
return num_written ? num_written : ret;
|
|
}
|
|
|
|
static ssize_t __btrfs_direct_write(struct kiocb *iocb,
|
|
const struct iovec *iov,
|
|
unsigned long nr_segs, loff_t pos,
|
|
loff_t *ppos, size_t count, size_t ocount)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct inode *inode = fdentry(file)->d_inode;
|
|
struct iov_iter i;
|
|
ssize_t written;
|
|
ssize_t written_buffered;
|
|
loff_t endbyte;
|
|
int err;
|
|
|
|
written = generic_file_direct_write(iocb, iov, &nr_segs, pos, ppos,
|
|
count, ocount);
|
|
|
|
/*
|
|
* the generic O_DIRECT will update in-memory i_size after the
|
|
* DIOs are done. But our endio handlers that update the on
|
|
* disk i_size never update past the in memory i_size. So we
|
|
* need one more update here to catch any additions to the
|
|
* file
|
|
*/
|
|
if (inode->i_size != BTRFS_I(inode)->disk_i_size) {
|
|
btrfs_ordered_update_i_size(inode, inode->i_size, NULL);
|
|
mark_inode_dirty(inode);
|
|
}
|
|
|
|
if (written < 0 || written == count)
|
|
return written;
|
|
|
|
pos += written;
|
|
count -= written;
|
|
iov_iter_init(&i, iov, nr_segs, count, written);
|
|
written_buffered = __btrfs_buffered_write(file, &i, pos);
|
|
if (written_buffered < 0) {
|
|
err = written_buffered;
|
|
goto out;
|
|
}
|
|
endbyte = pos + written_buffered - 1;
|
|
err = filemap_write_and_wait_range(file->f_mapping, pos, endbyte);
|
|
if (err)
|
|
goto out;
|
|
written += written_buffered;
|
|
*ppos = pos + written_buffered;
|
|
invalidate_mapping_pages(file->f_mapping, pos >> PAGE_CACHE_SHIFT,
|
|
endbyte >> PAGE_CACHE_SHIFT);
|
|
out:
|
|
return written ? written : err;
|
|
}
|
|
|
|
static ssize_t btrfs_file_aio_write(struct kiocb *iocb,
|
|
const struct iovec *iov,
|
|
unsigned long nr_segs, loff_t pos)
|
|
{
|
|
struct file *file = iocb->ki_filp;
|
|
struct inode *inode = fdentry(file)->d_inode;
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
loff_t *ppos = &iocb->ki_pos;
|
|
u64 start_pos;
|
|
ssize_t num_written = 0;
|
|
ssize_t err = 0;
|
|
size_t count, ocount;
|
|
|
|
vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
|
|
|
|
mutex_lock(&inode->i_mutex);
|
|
|
|
err = generic_segment_checks(iov, &nr_segs, &ocount, VERIFY_READ);
|
|
if (err) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
goto out;
|
|
}
|
|
count = ocount;
|
|
|
|
current->backing_dev_info = inode->i_mapping->backing_dev_info;
|
|
err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
|
|
if (err) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
goto out;
|
|
}
|
|
|
|
if (count == 0) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
goto out;
|
|
}
|
|
|
|
err = file_remove_suid(file);
|
|
if (err) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* If BTRFS flips readonly due to some impossible error
|
|
* (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR),
|
|
* although we have opened a file as writable, we have
|
|
* to stop this write operation to ensure FS consistency.
|
|
*/
|
|
if (root->fs_info->fs_state & BTRFS_SUPER_FLAG_ERROR) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
err = -EROFS;
|
|
goto out;
|
|
}
|
|
|
|
err = btrfs_update_time(file);
|
|
if (err) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
goto out;
|
|
}
|
|
BTRFS_I(inode)->sequence++;
|
|
|
|
start_pos = round_down(pos, root->sectorsize);
|
|
if (start_pos > i_size_read(inode)) {
|
|
err = btrfs_cont_expand(inode, i_size_read(inode), start_pos);
|
|
if (err) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
if (unlikely(file->f_flags & O_DIRECT)) {
|
|
num_written = __btrfs_direct_write(iocb, iov, nr_segs,
|
|
pos, ppos, count, ocount);
|
|
} else {
|
|
struct iov_iter i;
|
|
|
|
iov_iter_init(&i, iov, nr_segs, count, num_written);
|
|
|
|
num_written = __btrfs_buffered_write(file, &i, pos);
|
|
if (num_written > 0)
|
|
*ppos = pos + num_written;
|
|
}
|
|
|
|
mutex_unlock(&inode->i_mutex);
|
|
|
|
/*
|
|
* we want to make sure fsync finds this change
|
|
* but we haven't joined a transaction running right now.
|
|
*
|
|
* Later on, someone is sure to update the inode and get the
|
|
* real transid recorded.
|
|
*
|
|
* We set last_trans now to the fs_info generation + 1,
|
|
* this will either be one more than the running transaction
|
|
* or the generation used for the next transaction if there isn't
|
|
* one running right now.
|
|
*/
|
|
BTRFS_I(inode)->last_trans = root->fs_info->generation + 1;
|
|
if (num_written > 0 || num_written == -EIOCBQUEUED) {
|
|
err = generic_write_sync(file, pos, num_written);
|
|
if (err < 0 && num_written > 0)
|
|
num_written = err;
|
|
}
|
|
out:
|
|
current->backing_dev_info = NULL;
|
|
return num_written ? num_written : err;
|
|
}
|
|
|
|
int btrfs_release_file(struct inode *inode, struct file *filp)
|
|
{
|
|
/*
|
|
* ordered_data_close is set by settattr when we are about to truncate
|
|
* a file from a non-zero size to a zero size. This tries to
|
|
* flush down new bytes that may have been written if the
|
|
* application were using truncate to replace a file in place.
|
|
*/
|
|
if (BTRFS_I(inode)->ordered_data_close) {
|
|
BTRFS_I(inode)->ordered_data_close = 0;
|
|
btrfs_add_ordered_operation(NULL, BTRFS_I(inode)->root, inode);
|
|
if (inode->i_size > BTRFS_ORDERED_OPERATIONS_FLUSH_LIMIT)
|
|
filemap_flush(inode->i_mapping);
|
|
}
|
|
if (filp->private_data)
|
|
btrfs_ioctl_trans_end(filp);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* fsync call for both files and directories. This logs the inode into
|
|
* the tree log instead of forcing full commits whenever possible.
|
|
*
|
|
* It needs to call filemap_fdatawait so that all ordered extent updates are
|
|
* in the metadata btree are up to date for copying to the log.
|
|
*
|
|
* It drops the inode mutex before doing the tree log commit. This is an
|
|
* important optimization for directories because holding the mutex prevents
|
|
* new operations on the dir while we write to disk.
|
|
*/
|
|
int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
|
|
{
|
|
struct dentry *dentry = file->f_path.dentry;
|
|
struct inode *inode = dentry->d_inode;
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
int ret = 0;
|
|
struct btrfs_trans_handle *trans;
|
|
|
|
trace_btrfs_sync_file(file, datasync);
|
|
|
|
ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
|
|
if (ret)
|
|
return ret;
|
|
mutex_lock(&inode->i_mutex);
|
|
|
|
/* we wait first, since the writeback may change the inode */
|
|
root->log_batch++;
|
|
btrfs_wait_ordered_range(inode, 0, (u64)-1);
|
|
root->log_batch++;
|
|
|
|
/*
|
|
* check the transaction that last modified this inode
|
|
* and see if its already been committed
|
|
*/
|
|
if (!BTRFS_I(inode)->last_trans) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* if the last transaction that changed this file was before
|
|
* the current transaction, we can bail out now without any
|
|
* syncing
|
|
*/
|
|
smp_mb();
|
|
if (BTRFS_I(inode)->last_trans <=
|
|
root->fs_info->last_trans_committed) {
|
|
BTRFS_I(inode)->last_trans = 0;
|
|
mutex_unlock(&inode->i_mutex);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* ok we haven't committed the transaction yet, lets do a commit
|
|
*/
|
|
if (file->private_data)
|
|
btrfs_ioctl_trans_end(file);
|
|
|
|
trans = btrfs_start_transaction(root, 0);
|
|
if (IS_ERR(trans)) {
|
|
ret = PTR_ERR(trans);
|
|
mutex_unlock(&inode->i_mutex);
|
|
goto out;
|
|
}
|
|
|
|
ret = btrfs_log_dentry_safe(trans, root, dentry);
|
|
if (ret < 0) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
goto out;
|
|
}
|
|
|
|
/* we've logged all the items and now have a consistent
|
|
* version of the file in the log. It is possible that
|
|
* someone will come in and modify the file, but that's
|
|
* fine because the log is consistent on disk, and we
|
|
* have references to all of the file's extents
|
|
*
|
|
* It is possible that someone will come in and log the
|
|
* file again, but that will end up using the synchronization
|
|
* inside btrfs_sync_log to keep things safe.
|
|
*/
|
|
mutex_unlock(&inode->i_mutex);
|
|
|
|
if (ret != BTRFS_NO_LOG_SYNC) {
|
|
if (ret > 0) {
|
|
ret = btrfs_commit_transaction(trans, root);
|
|
} else {
|
|
ret = btrfs_sync_log(trans, root);
|
|
if (ret == 0)
|
|
ret = btrfs_end_transaction(trans, root);
|
|
else
|
|
ret = btrfs_commit_transaction(trans, root);
|
|
}
|
|
} else {
|
|
ret = btrfs_end_transaction(trans, root);
|
|
}
|
|
out:
|
|
return ret > 0 ? -EIO : ret;
|
|
}
|
|
|
|
static const struct vm_operations_struct btrfs_file_vm_ops = {
|
|
.fault = filemap_fault,
|
|
.page_mkwrite = btrfs_page_mkwrite,
|
|
};
|
|
|
|
static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma)
|
|
{
|
|
struct address_space *mapping = filp->f_mapping;
|
|
|
|
if (!mapping->a_ops->readpage)
|
|
return -ENOEXEC;
|
|
|
|
file_accessed(filp);
|
|
vma->vm_ops = &btrfs_file_vm_ops;
|
|
vma->vm_flags |= VM_CAN_NONLINEAR;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static long btrfs_fallocate(struct file *file, int mode,
|
|
loff_t offset, loff_t len)
|
|
{
|
|
struct inode *inode = file->f_path.dentry->d_inode;
|
|
struct extent_state *cached_state = NULL;
|
|
u64 cur_offset;
|
|
u64 last_byte;
|
|
u64 alloc_start;
|
|
u64 alloc_end;
|
|
u64 alloc_hint = 0;
|
|
u64 locked_end;
|
|
u64 mask = BTRFS_I(inode)->root->sectorsize - 1;
|
|
struct extent_map *em;
|
|
int ret;
|
|
|
|
alloc_start = offset & ~mask;
|
|
alloc_end = (offset + len + mask) & ~mask;
|
|
|
|
/* We only support the FALLOC_FL_KEEP_SIZE mode */
|
|
if (mode & ~FALLOC_FL_KEEP_SIZE)
|
|
return -EOPNOTSUPP;
|
|
|
|
/*
|
|
* Make sure we have enough space before we do the
|
|
* allocation.
|
|
*/
|
|
ret = btrfs_check_data_free_space(inode, len);
|
|
if (ret)
|
|
return ret;
|
|
|
|
/*
|
|
* wait for ordered IO before we have any locks. We'll loop again
|
|
* below with the locks held.
|
|
*/
|
|
btrfs_wait_ordered_range(inode, alloc_start, alloc_end - alloc_start);
|
|
|
|
mutex_lock(&inode->i_mutex);
|
|
ret = inode_newsize_ok(inode, alloc_end);
|
|
if (ret)
|
|
goto out;
|
|
|
|
if (alloc_start > inode->i_size) {
|
|
ret = btrfs_cont_expand(inode, i_size_read(inode),
|
|
alloc_start);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
|
|
locked_end = alloc_end - 1;
|
|
while (1) {
|
|
struct btrfs_ordered_extent *ordered;
|
|
|
|
/* the extent lock is ordered inside the running
|
|
* transaction
|
|
*/
|
|
lock_extent_bits(&BTRFS_I(inode)->io_tree, alloc_start,
|
|
locked_end, 0, &cached_state);
|
|
ordered = btrfs_lookup_first_ordered_extent(inode,
|
|
alloc_end - 1);
|
|
if (ordered &&
|
|
ordered->file_offset + ordered->len > alloc_start &&
|
|
ordered->file_offset < alloc_end) {
|
|
btrfs_put_ordered_extent(ordered);
|
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree,
|
|
alloc_start, locked_end,
|
|
&cached_state, GFP_NOFS);
|
|
/*
|
|
* we can't wait on the range with the transaction
|
|
* running or with the extent lock held
|
|
*/
|
|
btrfs_wait_ordered_range(inode, alloc_start,
|
|
alloc_end - alloc_start);
|
|
} else {
|
|
if (ordered)
|
|
btrfs_put_ordered_extent(ordered);
|
|
break;
|
|
}
|
|
}
|
|
|
|
cur_offset = alloc_start;
|
|
while (1) {
|
|
u64 actual_end;
|
|
|
|
em = btrfs_get_extent(inode, NULL, 0, cur_offset,
|
|
alloc_end - cur_offset, 0);
|
|
if (IS_ERR_OR_NULL(em)) {
|
|
if (!em)
|
|
ret = -ENOMEM;
|
|
else
|
|
ret = PTR_ERR(em);
|
|
break;
|
|
}
|
|
last_byte = min(extent_map_end(em), alloc_end);
|
|
actual_end = min_t(u64, extent_map_end(em), offset + len);
|
|
last_byte = (last_byte + mask) & ~mask;
|
|
|
|
if (em->block_start == EXTENT_MAP_HOLE ||
|
|
(cur_offset >= inode->i_size &&
|
|
!test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) {
|
|
ret = btrfs_prealloc_file_range(inode, mode, cur_offset,
|
|
last_byte - cur_offset,
|
|
1 << inode->i_blkbits,
|
|
offset + len,
|
|
&alloc_hint);
|
|
|
|
if (ret < 0) {
|
|
free_extent_map(em);
|
|
break;
|
|
}
|
|
} else if (actual_end > inode->i_size &&
|
|
!(mode & FALLOC_FL_KEEP_SIZE)) {
|
|
/*
|
|
* We didn't need to allocate any more space, but we
|
|
* still extended the size of the file so we need to
|
|
* update i_size.
|
|
*/
|
|
inode->i_ctime = CURRENT_TIME;
|
|
i_size_write(inode, actual_end);
|
|
btrfs_ordered_update_i_size(inode, actual_end, NULL);
|
|
}
|
|
free_extent_map(em);
|
|
|
|
cur_offset = last_byte;
|
|
if (cur_offset >= alloc_end) {
|
|
ret = 0;
|
|
break;
|
|
}
|
|
}
|
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree, alloc_start, locked_end,
|
|
&cached_state, GFP_NOFS);
|
|
out:
|
|
mutex_unlock(&inode->i_mutex);
|
|
/* Let go of our reservation. */
|
|
btrfs_free_reserved_data_space(inode, len);
|
|
return ret;
|
|
}
|
|
|
|
static int find_desired_extent(struct inode *inode, loff_t *offset, int origin)
|
|
{
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
struct extent_map *em;
|
|
struct extent_state *cached_state = NULL;
|
|
u64 lockstart = *offset;
|
|
u64 lockend = i_size_read(inode);
|
|
u64 start = *offset;
|
|
u64 orig_start = *offset;
|
|
u64 len = i_size_read(inode);
|
|
u64 last_end = 0;
|
|
int ret = 0;
|
|
|
|
lockend = max_t(u64, root->sectorsize, lockend);
|
|
if (lockend <= lockstart)
|
|
lockend = lockstart + root->sectorsize;
|
|
|
|
len = lockend - lockstart + 1;
|
|
|
|
len = max_t(u64, len, root->sectorsize);
|
|
if (inode->i_size == 0)
|
|
return -ENXIO;
|
|
|
|
lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, 0,
|
|
&cached_state);
|
|
|
|
/*
|
|
* Delalloc is such a pain. If we have a hole and we have pending
|
|
* delalloc for a portion of the hole we will get back a hole that
|
|
* exists for the entire range since it hasn't been actually written
|
|
* yet. So to take care of this case we need to look for an extent just
|
|
* before the position we want in case there is outstanding delalloc
|
|
* going on here.
|
|
*/
|
|
if (origin == SEEK_HOLE && start != 0) {
|
|
if (start <= root->sectorsize)
|
|
em = btrfs_get_extent_fiemap(inode, NULL, 0, 0,
|
|
root->sectorsize, 0);
|
|
else
|
|
em = btrfs_get_extent_fiemap(inode, NULL, 0,
|
|
start - root->sectorsize,
|
|
root->sectorsize, 0);
|
|
if (IS_ERR(em)) {
|
|
ret = PTR_ERR(em);
|
|
goto out;
|
|
}
|
|
last_end = em->start + em->len;
|
|
if (em->block_start == EXTENT_MAP_DELALLOC)
|
|
last_end = min_t(u64, last_end, inode->i_size);
|
|
free_extent_map(em);
|
|
}
|
|
|
|
while (1) {
|
|
em = btrfs_get_extent_fiemap(inode, NULL, 0, start, len, 0);
|
|
if (IS_ERR(em)) {
|
|
ret = PTR_ERR(em);
|
|
break;
|
|
}
|
|
|
|
if (em->block_start == EXTENT_MAP_HOLE) {
|
|
if (test_bit(EXTENT_FLAG_VACANCY, &em->flags)) {
|
|
if (last_end <= orig_start) {
|
|
free_extent_map(em);
|
|
ret = -ENXIO;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (origin == SEEK_HOLE) {
|
|
*offset = start;
|
|
free_extent_map(em);
|
|
break;
|
|
}
|
|
} else {
|
|
if (origin == SEEK_DATA) {
|
|
if (em->block_start == EXTENT_MAP_DELALLOC) {
|
|
if (start >= inode->i_size) {
|
|
free_extent_map(em);
|
|
ret = -ENXIO;
|
|
break;
|
|
}
|
|
}
|
|
|
|
*offset = start;
|
|
free_extent_map(em);
|
|
break;
|
|
}
|
|
}
|
|
|
|
start = em->start + em->len;
|
|
last_end = em->start + em->len;
|
|
|
|
if (em->block_start == EXTENT_MAP_DELALLOC)
|
|
last_end = min_t(u64, last_end, inode->i_size);
|
|
|
|
if (test_bit(EXTENT_FLAG_VACANCY, &em->flags)) {
|
|
free_extent_map(em);
|
|
ret = -ENXIO;
|
|
break;
|
|
}
|
|
free_extent_map(em);
|
|
cond_resched();
|
|
}
|
|
if (!ret)
|
|
*offset = min(*offset, inode->i_size);
|
|
out:
|
|
unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend,
|
|
&cached_state, GFP_NOFS);
|
|
return ret;
|
|
}
|
|
|
|
static loff_t btrfs_file_llseek(struct file *file, loff_t offset, int origin)
|
|
{
|
|
struct inode *inode = file->f_mapping->host;
|
|
int ret;
|
|
|
|
mutex_lock(&inode->i_mutex);
|
|
switch (origin) {
|
|
case SEEK_END:
|
|
case SEEK_CUR:
|
|
offset = generic_file_llseek(file, offset, origin);
|
|
goto out;
|
|
case SEEK_DATA:
|
|
case SEEK_HOLE:
|
|
if (offset >= i_size_read(inode)) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
return -ENXIO;
|
|
}
|
|
|
|
ret = find_desired_extent(inode, &offset, origin);
|
|
if (ret) {
|
|
mutex_unlock(&inode->i_mutex);
|
|
return ret;
|
|
}
|
|
}
|
|
|
|
if (offset < 0 && !(file->f_mode & FMODE_UNSIGNED_OFFSET)) {
|
|
offset = -EINVAL;
|
|
goto out;
|
|
}
|
|
if (offset > inode->i_sb->s_maxbytes) {
|
|
offset = -EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
/* Special lock needed here? */
|
|
if (offset != file->f_pos) {
|
|
file->f_pos = offset;
|
|
file->f_version = 0;
|
|
}
|
|
out:
|
|
mutex_unlock(&inode->i_mutex);
|
|
return offset;
|
|
}
|
|
|
|
const struct file_operations btrfs_file_operations = {
|
|
.llseek = btrfs_file_llseek,
|
|
.read = do_sync_read,
|
|
.write = do_sync_write,
|
|
.aio_read = generic_file_aio_read,
|
|
.splice_read = generic_file_splice_read,
|
|
.aio_write = btrfs_file_aio_write,
|
|
.mmap = btrfs_file_mmap,
|
|
.open = generic_file_open,
|
|
.release = btrfs_release_file,
|
|
.fsync = btrfs_sync_file,
|
|
.fallocate = btrfs_fallocate,
|
|
.unlocked_ioctl = btrfs_ioctl,
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_ioctl = btrfs_ioctl,
|
|
#endif
|
|
};
|