![Alexey Dobriyan](/assets/img/avatar_default.png)
* Remove smp_lock.h from files which don't need it (including some headers!) * Add smp_lock.h to files which do need it * Make smp_lock.h include conditional in hardirq.h It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT This will make hardirq.h inclusion cheaper for every PREEMPT=n config (which includes allmodconfig/allyesconfig, BTW) Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1233 lines
33 KiB
C
1233 lines
33 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/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 "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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/* 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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int write_bytes,
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struct page **prepared_pages,
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const char __user *buf)
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{
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long page_fault = 0;
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int i;
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int offset = pos & (PAGE_CACHE_SIZE - 1);
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for (i = 0; i < num_pages && write_bytes > 0; i++, offset = 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[i];
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fault_in_pages_readable(buf, count);
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/* Copy data from userspace to the current page */
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kmap(page);
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page_fault = __copy_from_user(page_address(page) + offset,
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buf, count);
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/* Flush processor's dcache for this page */
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flush_dcache_page(page);
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kunmap(page);
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buf += count;
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write_bytes -= count;
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if (page_fault)
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break;
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}
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return page_fault ? -EFAULT : 0;
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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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static noinline 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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if (!pages[i])
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break;
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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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static noinline int dirty_and_release_pages(struct btrfs_trans_handle *trans,
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struct btrfs_root *root,
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struct file *file,
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struct page **pages,
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size_t num_pages,
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loff_t pos,
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size_t write_bytes)
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{
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int err = 0;
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int i;
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struct inode *inode = fdentry(file)->d_inode;
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struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
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u64 hint_byte;
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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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lock_extent(io_tree, start_pos, end_of_last_block, GFP_NOFS);
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trans = btrfs_join_transaction(root, 1);
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if (!trans) {
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err = -ENOMEM;
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goto out_unlock;
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}
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btrfs_set_trans_block_group(trans, inode);
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hint_byte = 0;
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set_extent_uptodate(io_tree, start_pos, end_of_last_block, GFP_NOFS);
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/* check for reserved extents on each page, we don't want
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* to reset the delalloc bit on things that already have
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* extents reserved.
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*/
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btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block);
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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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if (end_pos > isize) {
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i_size_write(inode, end_pos);
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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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}
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err = btrfs_end_transaction(trans, root);
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out_unlock:
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unlock_extent(io_tree, start_pos, end_of_last_block, GFP_NOFS);
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return err;
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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(GFP_NOFS);
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if (!split2)
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split2 = alloc_extent_map(GFP_NOFS);
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spin_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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spin_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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spin_unlock(&em_tree->lock);
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if (em->start <= start &&
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(!testend || em->start + em->len >= start + len)) {
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free_extent_map(em);
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break;
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}
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if (start < em->start) {
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len = em->start - start;
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} else {
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len = start + len - (em->start + em->len);
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start = em->start + em->len;
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}
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free_extent_map(em);
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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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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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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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split->bdev = em->bdev;
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split->flags = flags;
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ret = add_extent_mapping(em_tree, split);
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BUG_ON(ret);
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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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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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if (compressed) {
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split->block_len = em->block_len;
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split->block_start = em->block_start;
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split->orig_start = em->orig_start;
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} else {
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split->block_len = split->len;
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split->block_start = em->block_start + diff;
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split->orig_start = split->start;
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}
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ret = add_extent_mapping(em_tree, split);
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BUG_ON(ret);
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free_extent_map(split);
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split = NULL;
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}
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spin_unlock(&em_tree->lock);
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/* once for us */
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free_extent_map(em);
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/* once for the tree*/
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free_extent_map(em);
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}
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if (split)
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free_extent_map(split);
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if (split2)
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free_extent_map(split2);
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return 0;
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}
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/*
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* this is very complex, but the basic idea is to drop all extents
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* in the range start - end. hint_block is filled in with a block number
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* that would be a good hint to the block allocator for this file.
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*
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* If an extent intersects the range but is not entirely inside the range
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* it is either truncated or split. Anything entirely inside the range
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* is deleted from the tree.
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*
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* inline_limit is used to tell this code which offsets in the file to keep
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* if they contain inline extents.
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*/
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noinline int btrfs_drop_extents(struct btrfs_trans_handle *trans,
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struct btrfs_root *root, struct inode *inode,
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u64 start, u64 end, u64 locked_end,
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u64 inline_limit, u64 *hint_byte)
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{
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u64 extent_end = 0;
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u64 search_start = start;
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u64 ram_bytes = 0;
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u64 disk_bytenr = 0;
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u64 orig_locked_end = locked_end;
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u8 compression;
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u8 encryption;
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u16 other_encoding = 0;
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struct extent_buffer *leaf;
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struct btrfs_file_extent_item *extent;
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struct btrfs_path *path;
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struct btrfs_key key;
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struct btrfs_file_extent_item old;
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int keep;
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int slot;
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int bookend;
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int found_type = 0;
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int found_extent;
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int found_inline;
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int recow;
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int ret;
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inline_limit = 0;
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btrfs_drop_extent_cache(inode, start, end - 1, 0);
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path = btrfs_alloc_path();
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if (!path)
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return -ENOMEM;
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while (1) {
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recow = 0;
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btrfs_release_path(root, path);
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ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
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search_start, -1);
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if (ret < 0)
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goto out;
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if (ret > 0) {
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if (path->slots[0] == 0) {
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ret = 0;
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goto out;
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}
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path->slots[0]--;
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}
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next_slot:
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keep = 0;
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bookend = 0;
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found_extent = 0;
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found_inline = 0;
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compression = 0;
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encryption = 0;
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extent = NULL;
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leaf = path->nodes[0];
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slot = path->slots[0];
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ret = 0;
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btrfs_item_key_to_cpu(leaf, &key, slot);
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if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY &&
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key.offset >= end) {
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goto out;
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}
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if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
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key.objectid != inode->i_ino) {
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goto out;
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}
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if (recow) {
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search_start = max(key.offset, start);
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continue;
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}
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if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
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extent = btrfs_item_ptr(leaf, slot,
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struct btrfs_file_extent_item);
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found_type = btrfs_file_extent_type(leaf, extent);
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compression = btrfs_file_extent_compression(leaf,
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extent);
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encryption = btrfs_file_extent_encryption(leaf,
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extent);
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other_encoding = btrfs_file_extent_other_encoding(leaf,
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extent);
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if (found_type == BTRFS_FILE_EXTENT_REG ||
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found_type == BTRFS_FILE_EXTENT_PREALLOC) {
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extent_end =
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btrfs_file_extent_disk_bytenr(leaf,
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extent);
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if (extent_end)
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*hint_byte = extent_end;
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extent_end = key.offset +
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btrfs_file_extent_num_bytes(leaf, extent);
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ram_bytes = btrfs_file_extent_ram_bytes(leaf,
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extent);
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found_extent = 1;
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} else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
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found_inline = 1;
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extent_end = key.offset +
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btrfs_file_extent_inline_len(leaf, extent);
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}
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} else {
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extent_end = search_start;
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}
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/* we found nothing we can drop */
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if ((!found_extent && !found_inline) ||
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search_start >= extent_end) {
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int nextret;
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u32 nritems;
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nritems = btrfs_header_nritems(leaf);
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if (slot >= nritems - 1) {
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nextret = btrfs_next_leaf(root, path);
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if (nextret)
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goto out;
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recow = 1;
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} else {
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path->slots[0]++;
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}
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goto next_slot;
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}
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if (end <= extent_end && start >= key.offset && found_inline)
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*hint_byte = EXTENT_MAP_INLINE;
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|
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if (found_extent) {
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read_extent_buffer(leaf, &old, (unsigned long)extent,
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sizeof(old));
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}
|
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|
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if (end < extent_end && end >= key.offset) {
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bookend = 1;
|
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if (found_inline && start <= key.offset)
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keep = 1;
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}
|
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|
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if (bookend && found_extent) {
|
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if (locked_end < extent_end) {
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ret = try_lock_extent(&BTRFS_I(inode)->io_tree,
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locked_end, extent_end - 1,
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GFP_NOFS);
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if (!ret) {
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btrfs_release_path(root, path);
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lock_extent(&BTRFS_I(inode)->io_tree,
|
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locked_end, extent_end - 1,
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GFP_NOFS);
|
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locked_end = extent_end;
|
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continue;
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}
|
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locked_end = extent_end;
|
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}
|
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disk_bytenr = le64_to_cpu(old.disk_bytenr);
|
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if (disk_bytenr != 0) {
|
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ret = btrfs_inc_extent_ref(trans, root,
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disk_bytenr,
|
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le64_to_cpu(old.disk_num_bytes), 0,
|
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root->root_key.objectid,
|
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key.objectid, key.offset -
|
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le64_to_cpu(old.offset));
|
|
BUG_ON(ret);
|
|
}
|
|
}
|
|
|
|
if (found_inline) {
|
|
u64 mask = root->sectorsize - 1;
|
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search_start = (extent_end + mask) & ~mask;
|
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} else
|
|
search_start = extent_end;
|
|
|
|
/* truncate existing extent */
|
|
if (start > key.offset) {
|
|
u64 new_num;
|
|
u64 old_num;
|
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keep = 1;
|
|
WARN_ON(start & (root->sectorsize - 1));
|
|
if (found_extent) {
|
|
new_num = start - key.offset;
|
|
old_num = btrfs_file_extent_num_bytes(leaf,
|
|
extent);
|
|
*hint_byte =
|
|
btrfs_file_extent_disk_bytenr(leaf,
|
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extent);
|
|
if (btrfs_file_extent_disk_bytenr(leaf,
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extent)) {
|
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inode_sub_bytes(inode, old_num -
|
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new_num);
|
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}
|
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btrfs_set_file_extent_num_bytes(leaf,
|
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extent, new_num);
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
} else if (key.offset < inline_limit &&
|
|
(end > extent_end) &&
|
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(inline_limit < extent_end)) {
|
|
u32 new_size;
|
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new_size = btrfs_file_extent_calc_inline_size(
|
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inline_limit - key.offset);
|
|
inode_sub_bytes(inode, extent_end -
|
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inline_limit);
|
|
btrfs_set_file_extent_ram_bytes(leaf, extent,
|
|
new_size);
|
|
if (!compression && !encryption) {
|
|
btrfs_truncate_item(trans, root, path,
|
|
new_size, 1);
|
|
}
|
|
}
|
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}
|
|
/* delete the entire extent */
|
|
if (!keep) {
|
|
if (found_inline)
|
|
inode_sub_bytes(inode, extent_end -
|
|
key.offset);
|
|
ret = btrfs_del_item(trans, root, path);
|
|
/* TODO update progress marker and return */
|
|
BUG_ON(ret);
|
|
extent = NULL;
|
|
btrfs_release_path(root, path);
|
|
/* the extent will be freed later */
|
|
}
|
|
if (bookend && found_inline && start <= key.offset) {
|
|
u32 new_size;
|
|
new_size = btrfs_file_extent_calc_inline_size(
|
|
extent_end - end);
|
|
inode_sub_bytes(inode, end - key.offset);
|
|
btrfs_set_file_extent_ram_bytes(leaf, extent,
|
|
new_size);
|
|
if (!compression && !encryption)
|
|
ret = btrfs_truncate_item(trans, root, path,
|
|
new_size, 0);
|
|
BUG_ON(ret);
|
|
}
|
|
/* create bookend, splitting the extent in two */
|
|
if (bookend && found_extent) {
|
|
struct btrfs_key ins;
|
|
ins.objectid = inode->i_ino;
|
|
ins.offset = end;
|
|
btrfs_set_key_type(&ins, BTRFS_EXTENT_DATA_KEY);
|
|
|
|
btrfs_release_path(root, path);
|
|
path->leave_spinning = 1;
|
|
ret = btrfs_insert_empty_item(trans, root, path, &ins,
|
|
sizeof(*extent));
|
|
BUG_ON(ret);
|
|
|
|
leaf = path->nodes[0];
|
|
extent = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
write_extent_buffer(leaf, &old,
|
|
(unsigned long)extent, sizeof(old));
|
|
|
|
btrfs_set_file_extent_compression(leaf, extent,
|
|
compression);
|
|
btrfs_set_file_extent_encryption(leaf, extent,
|
|
encryption);
|
|
btrfs_set_file_extent_other_encoding(leaf, extent,
|
|
other_encoding);
|
|
btrfs_set_file_extent_offset(leaf, extent,
|
|
le64_to_cpu(old.offset) + end - key.offset);
|
|
WARN_ON(le64_to_cpu(old.num_bytes) <
|
|
(extent_end - end));
|
|
btrfs_set_file_extent_num_bytes(leaf, extent,
|
|
extent_end - end);
|
|
|
|
/*
|
|
* set the ram bytes to the size of the full extent
|
|
* before splitting. This is a worst case flag,
|
|
* but its the best we can do because we don't know
|
|
* how splitting affects compression
|
|
*/
|
|
btrfs_set_file_extent_ram_bytes(leaf, extent,
|
|
ram_bytes);
|
|
btrfs_set_file_extent_type(leaf, extent, found_type);
|
|
|
|
btrfs_unlock_up_safe(path, 1);
|
|
btrfs_mark_buffer_dirty(path->nodes[0]);
|
|
btrfs_set_lock_blocking(path->nodes[0]);
|
|
|
|
path->leave_spinning = 0;
|
|
btrfs_release_path(root, path);
|
|
if (disk_bytenr != 0)
|
|
inode_add_bytes(inode, extent_end - end);
|
|
}
|
|
|
|
if (found_extent && !keep) {
|
|
u64 old_disk_bytenr = le64_to_cpu(old.disk_bytenr);
|
|
|
|
if (old_disk_bytenr != 0) {
|
|
inode_sub_bytes(inode,
|
|
le64_to_cpu(old.num_bytes));
|
|
ret = btrfs_free_extent(trans, root,
|
|
old_disk_bytenr,
|
|
le64_to_cpu(old.disk_num_bytes),
|
|
0, root->root_key.objectid,
|
|
key.objectid, key.offset -
|
|
le64_to_cpu(old.offset));
|
|
BUG_ON(ret);
|
|
*hint_byte = old_disk_bytenr;
|
|
}
|
|
}
|
|
|
|
if (search_start >= end) {
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
}
|
|
out:
|
|
btrfs_free_path(path);
|
|
if (locked_end > orig_locked_end) {
|
|
unlock_extent(&BTRFS_I(inode)->io_tree, orig_locked_end,
|
|
locked_end - 1, GFP_NOFS);
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static int extent_mergeable(struct extent_buffer *leaf, int slot,
|
|
u64 objectid, u64 bytenr, 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_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 btrfs_root *root,
|
|
struct inode *inode, u64 start, u64 end)
|
|
{
|
|
struct extent_buffer *leaf;
|
|
struct btrfs_path *path;
|
|
struct btrfs_file_extent_item *fi;
|
|
struct btrfs_key key;
|
|
u64 bytenr;
|
|
u64 num_bytes;
|
|
u64 extent_end;
|
|
u64 orig_offset;
|
|
u64 other_start;
|
|
u64 other_end;
|
|
u64 split = start;
|
|
u64 locked_end = end;
|
|
int extent_type;
|
|
int split_end = 1;
|
|
int ret;
|
|
|
|
btrfs_drop_extent_cache(inode, start, end - 1, 0);
|
|
|
|
path = btrfs_alloc_path();
|
|
BUG_ON(!path);
|
|
again:
|
|
key.objectid = inode->i_ino;
|
|
key.type = BTRFS_EXTENT_DATA_KEY;
|
|
if (split == start)
|
|
key.offset = split;
|
|
else
|
|
key.offset = split - 1;
|
|
|
|
ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
|
|
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 != inode->i_ino ||
|
|
key.type != BTRFS_EXTENT_DATA_KEY);
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
extent_type = btrfs_file_extent_type(leaf, fi);
|
|
BUG_ON(extent_type != 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);
|
|
|
|
if (key.offset == start)
|
|
split = end;
|
|
|
|
if (key.offset == start && extent_end == end) {
|
|
int del_nr = 0;
|
|
int del_slot = 0;
|
|
other_start = end;
|
|
other_end = 0;
|
|
if (extent_mergeable(leaf, path->slots[0] + 1, inode->i_ino,
|
|
bytenr, &other_start, &other_end)) {
|
|
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,
|
|
inode->i_ino, orig_offset);
|
|
BUG_ON(ret);
|
|
}
|
|
other_start = 0;
|
|
other_end = start;
|
|
if (extent_mergeable(leaf, path->slots[0] - 1, inode->i_ino,
|
|
bytenr, &other_start, &other_end)) {
|
|
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,
|
|
inode->i_ino, orig_offset);
|
|
BUG_ON(ret);
|
|
}
|
|
split_end = 0;
|
|
if (del_nr == 0) {
|
|
btrfs_set_file_extent_type(leaf, fi,
|
|
BTRFS_FILE_EXTENT_REG);
|
|
goto done;
|
|
}
|
|
|
|
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);
|
|
BUG_ON(ret);
|
|
goto release;
|
|
} else if (split == start) {
|
|
if (locked_end < extent_end) {
|
|
ret = try_lock_extent(&BTRFS_I(inode)->io_tree,
|
|
locked_end, extent_end - 1, GFP_NOFS);
|
|
if (!ret) {
|
|
btrfs_release_path(root, path);
|
|
lock_extent(&BTRFS_I(inode)->io_tree,
|
|
locked_end, extent_end - 1, GFP_NOFS);
|
|
locked_end = extent_end;
|
|
goto again;
|
|
}
|
|
locked_end = extent_end;
|
|
}
|
|
btrfs_set_file_extent_num_bytes(leaf, fi, split - key.offset);
|
|
} else {
|
|
BUG_ON(key.offset != start);
|
|
key.offset = split;
|
|
btrfs_set_file_extent_offset(leaf, fi, key.offset -
|
|
orig_offset);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi, extent_end - split);
|
|
btrfs_set_item_key_safe(trans, root, path, &key);
|
|
extent_end = split;
|
|
}
|
|
|
|
if (extent_end == end) {
|
|
split_end = 0;
|
|
extent_type = BTRFS_FILE_EXTENT_REG;
|
|
}
|
|
if (extent_end == end && split == start) {
|
|
other_start = end;
|
|
other_end = 0;
|
|
if (extent_mergeable(leaf, path->slots[0] + 1, inode->i_ino,
|
|
bytenr, &other_start, &other_end)) {
|
|
path->slots[0]++;
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
key.offset = split;
|
|
btrfs_set_item_key_safe(trans, root, path, &key);
|
|
btrfs_set_file_extent_offset(leaf, fi, key.offset -
|
|
orig_offset);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi,
|
|
other_end - split);
|
|
goto done;
|
|
}
|
|
}
|
|
if (extent_end == end && split == end) {
|
|
other_start = 0;
|
|
other_end = start;
|
|
if (extent_mergeable(leaf, path->slots[0] - 1 , inode->i_ino,
|
|
bytenr, &other_start, &other_end)) {
|
|
path->slots[0]--;
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi, extent_end -
|
|
other_start);
|
|
goto done;
|
|
}
|
|
}
|
|
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
|
|
ret = btrfs_inc_extent_ref(trans, root, bytenr, num_bytes, 0,
|
|
root->root_key.objectid,
|
|
inode->i_ino, orig_offset);
|
|
BUG_ON(ret);
|
|
btrfs_release_path(root, path);
|
|
|
|
key.offset = start;
|
|
ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(*fi));
|
|
BUG_ON(ret);
|
|
|
|
leaf = path->nodes[0];
|
|
fi = btrfs_item_ptr(leaf, path->slots[0],
|
|
struct btrfs_file_extent_item);
|
|
btrfs_set_file_extent_generation(leaf, fi, trans->transid);
|
|
btrfs_set_file_extent_type(leaf, fi, extent_type);
|
|
btrfs_set_file_extent_disk_bytenr(leaf, fi, bytenr);
|
|
btrfs_set_file_extent_disk_num_bytes(leaf, fi, num_bytes);
|
|
btrfs_set_file_extent_offset(leaf, fi, key.offset - orig_offset);
|
|
btrfs_set_file_extent_num_bytes(leaf, fi, extent_end - key.offset);
|
|
btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes);
|
|
btrfs_set_file_extent_compression(leaf, fi, 0);
|
|
btrfs_set_file_extent_encryption(leaf, fi, 0);
|
|
btrfs_set_file_extent_other_encoding(leaf, fi, 0);
|
|
done:
|
|
btrfs_mark_buffer_dirty(leaf);
|
|
|
|
release:
|
|
btrfs_release_path(root, path);
|
|
if (split_end && split == start) {
|
|
split = end;
|
|
goto again;
|
|
}
|
|
if (locked_end > end) {
|
|
unlock_extent(&BTRFS_I(inode)->io_tree, end, locked_end - 1,
|
|
GFP_NOFS);
|
|
}
|
|
btrfs_free_path(path);
|
|
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,
|
|
unsigned long last_index, size_t write_bytes)
|
|
{
|
|
int i;
|
|
unsigned long index = pos >> PAGE_CACHE_SHIFT;
|
|
struct inode *inode = fdentry(file)->d_inode;
|
|
int err = 0;
|
|
u64 start_pos;
|
|
u64 last_pos;
|
|
|
|
start_pos = pos & ~((u64)root->sectorsize - 1);
|
|
last_pos = ((u64)index + num_pages) << PAGE_CACHE_SHIFT;
|
|
|
|
if (start_pos > inode->i_size) {
|
|
err = btrfs_cont_expand(inode, start_pos);
|
|
if (err)
|
|
return err;
|
|
}
|
|
|
|
memset(pages, 0, num_pages * sizeof(struct page *));
|
|
again:
|
|
for (i = 0; i < num_pages; i++) {
|
|
pages[i] = grab_cache_page(inode->i_mapping, index + i);
|
|
if (!pages[i]) {
|
|
err = -ENOMEM;
|
|
BUG_ON(1);
|
|
}
|
|
wait_on_page_writeback(pages[i]);
|
|
}
|
|
if (start_pos < inode->i_size) {
|
|
struct btrfs_ordered_extent *ordered;
|
|
lock_extent(&BTRFS_I(inode)->io_tree,
|
|
start_pos, last_pos - 1, GFP_NOFS);
|
|
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(&BTRFS_I(inode)->io_tree,
|
|
start_pos, last_pos - 1, 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_bits(&BTRFS_I(inode)->io_tree, start_pos,
|
|
last_pos - 1, EXTENT_DIRTY | EXTENT_DELALLOC,
|
|
GFP_NOFS);
|
|
unlock_extent(&BTRFS_I(inode)->io_tree,
|
|
start_pos, last_pos - 1, GFP_NOFS);
|
|
}
|
|
for (i = 0; i < num_pages; i++) {
|
|
clear_page_dirty_for_io(pages[i]);
|
|
set_page_extent_mapped(pages[i]);
|
|
WARN_ON(!PageLocked(pages[i]));
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
|
|
size_t count, loff_t *ppos)
|
|
{
|
|
loff_t pos;
|
|
loff_t start_pos;
|
|
ssize_t num_written = 0;
|
|
ssize_t err = 0;
|
|
int ret = 0;
|
|
struct inode *inode = fdentry(file)->d_inode;
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
struct page **pages = NULL;
|
|
int nrptrs;
|
|
struct page *pinned[2];
|
|
unsigned long first_index;
|
|
unsigned long last_index;
|
|
int will_write;
|
|
|
|
will_write = ((file->f_flags & O_SYNC) || IS_SYNC(inode) ||
|
|
(file->f_flags & O_DIRECT));
|
|
|
|
nrptrs = min((count + PAGE_CACHE_SIZE - 1) / PAGE_CACHE_SIZE,
|
|
PAGE_CACHE_SIZE / (sizeof(struct page *)));
|
|
pinned[0] = NULL;
|
|
pinned[1] = NULL;
|
|
|
|
pos = *ppos;
|
|
start_pos = pos;
|
|
|
|
vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
|
|
current->backing_dev_info = inode->i_mapping->backing_dev_info;
|
|
err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
|
|
if (err)
|
|
goto out_nolock;
|
|
if (count == 0)
|
|
goto out_nolock;
|
|
|
|
err = file_remove_suid(file);
|
|
if (err)
|
|
goto out_nolock;
|
|
file_update_time(file);
|
|
|
|
pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);
|
|
|
|
mutex_lock(&inode->i_mutex);
|
|
BTRFS_I(inode)->sequence++;
|
|
first_index = pos >> PAGE_CACHE_SHIFT;
|
|
last_index = (pos + count) >> PAGE_CACHE_SHIFT;
|
|
|
|
/*
|
|
* there are lots of better ways to do this, but this code
|
|
* makes sure the first and last page in the file range are
|
|
* up to date and ready for cow
|
|
*/
|
|
if ((pos & (PAGE_CACHE_SIZE - 1))) {
|
|
pinned[0] = grab_cache_page(inode->i_mapping, first_index);
|
|
if (!PageUptodate(pinned[0])) {
|
|
ret = btrfs_readpage(NULL, pinned[0]);
|
|
BUG_ON(ret);
|
|
wait_on_page_locked(pinned[0]);
|
|
} else {
|
|
unlock_page(pinned[0]);
|
|
}
|
|
}
|
|
if ((pos + count) & (PAGE_CACHE_SIZE - 1)) {
|
|
pinned[1] = grab_cache_page(inode->i_mapping, last_index);
|
|
if (!PageUptodate(pinned[1])) {
|
|
ret = btrfs_readpage(NULL, pinned[1]);
|
|
BUG_ON(ret);
|
|
wait_on_page_locked(pinned[1]);
|
|
} else {
|
|
unlock_page(pinned[1]);
|
|
}
|
|
}
|
|
|
|
while (count > 0) {
|
|
size_t offset = pos & (PAGE_CACHE_SIZE - 1);
|
|
size_t write_bytes = min(count, nrptrs *
|
|
(size_t)PAGE_CACHE_SIZE -
|
|
offset);
|
|
size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >>
|
|
PAGE_CACHE_SHIFT;
|
|
|
|
WARN_ON(num_pages > nrptrs);
|
|
memset(pages, 0, sizeof(struct page *) * nrptrs);
|
|
|
|
ret = btrfs_check_data_free_space(root, inode, write_bytes);
|
|
if (ret)
|
|
goto out;
|
|
|
|
ret = prepare_pages(root, file, pages, num_pages,
|
|
pos, first_index, last_index,
|
|
write_bytes);
|
|
if (ret) {
|
|
btrfs_free_reserved_data_space(root, inode,
|
|
write_bytes);
|
|
goto out;
|
|
}
|
|
|
|
ret = btrfs_copy_from_user(pos, num_pages,
|
|
write_bytes, pages, buf);
|
|
if (ret) {
|
|
btrfs_free_reserved_data_space(root, inode,
|
|
write_bytes);
|
|
btrfs_drop_pages(pages, num_pages);
|
|
goto out;
|
|
}
|
|
|
|
ret = dirty_and_release_pages(NULL, root, file, pages,
|
|
num_pages, pos, write_bytes);
|
|
btrfs_drop_pages(pages, num_pages);
|
|
if (ret) {
|
|
btrfs_free_reserved_data_space(root, inode,
|
|
write_bytes);
|
|
goto out;
|
|
}
|
|
|
|
if (will_write) {
|
|
btrfs_fdatawrite_range(inode->i_mapping, pos,
|
|
pos + write_bytes - 1,
|
|
WB_SYNC_ALL);
|
|
} else {
|
|
balance_dirty_pages_ratelimited_nr(inode->i_mapping,
|
|
num_pages);
|
|
if (num_pages <
|
|
(root->leafsize >> PAGE_CACHE_SHIFT) + 1)
|
|
btrfs_btree_balance_dirty(root, 1);
|
|
btrfs_throttle(root);
|
|
}
|
|
|
|
buf += write_bytes;
|
|
count -= write_bytes;
|
|
pos += write_bytes;
|
|
num_written += write_bytes;
|
|
|
|
cond_resched();
|
|
}
|
|
out:
|
|
mutex_unlock(&inode->i_mutex);
|
|
if (ret)
|
|
err = ret;
|
|
|
|
out_nolock:
|
|
kfree(pages);
|
|
if (pinned[0])
|
|
page_cache_release(pinned[0]);
|
|
if (pinned[1])
|
|
page_cache_release(pinned[1]);
|
|
*ppos = pos;
|
|
|
|
/*
|
|
* 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 && will_write) {
|
|
struct btrfs_trans_handle *trans;
|
|
|
|
err = btrfs_wait_ordered_range(inode, start_pos, num_written);
|
|
if (err)
|
|
num_written = err;
|
|
|
|
if ((file->f_flags & O_SYNC) || IS_SYNC(inode)) {
|
|
trans = btrfs_start_transaction(root, 1);
|
|
ret = btrfs_log_dentry_safe(trans, root,
|
|
file->f_dentry);
|
|
if (ret == 0) {
|
|
ret = btrfs_sync_log(trans, root);
|
|
if (ret == 0)
|
|
btrfs_end_transaction(trans, root);
|
|
else
|
|
btrfs_commit_transaction(trans, root);
|
|
} else {
|
|
btrfs_commit_transaction(trans, root);
|
|
}
|
|
}
|
|
if (file->f_flags & O_DIRECT) {
|
|
invalidate_mapping_pages(inode->i_mapping,
|
|
start_pos >> PAGE_CACHE_SHIFT,
|
|
(start_pos + num_written - 1) >> PAGE_CACHE_SHIFT);
|
|
}
|
|
}
|
|
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, struct dentry *dentry, int datasync)
|
|
{
|
|
struct inode *inode = dentry->d_inode;
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
int ret = 0;
|
|
struct btrfs_trans_handle *trans;
|
|
|
|
/*
|
|
* check the transaction that last modified this inode
|
|
* and see if its already been committed
|
|
*/
|
|
if (!BTRFS_I(inode)->last_trans)
|
|
goto out;
|
|
|
|
mutex_lock(&root->fs_info->trans_mutex);
|
|
if (BTRFS_I(inode)->last_trans <=
|
|
root->fs_info->last_trans_committed) {
|
|
BTRFS_I(inode)->last_trans = 0;
|
|
mutex_unlock(&root->fs_info->trans_mutex);
|
|
goto out;
|
|
}
|
|
mutex_unlock(&root->fs_info->trans_mutex);
|
|
|
|
root->log_batch++;
|
|
filemap_fdatawrite(inode->i_mapping);
|
|
btrfs_wait_ordered_range(inode, 0, (u64)-1);
|
|
root->log_batch++;
|
|
|
|
if (datasync && !(inode->i_state & I_DIRTY_PAGES))
|
|
goto out;
|
|
/*
|
|
* ok we haven't committed the transaction yet, lets do a commit
|
|
*/
|
|
if (file && file->private_data)
|
|
btrfs_ioctl_trans_end(file);
|
|
|
|
trans = btrfs_start_transaction(root, 1);
|
|
if (!trans) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
ret = btrfs_log_dentry_safe(trans, root, dentry);
|
|
if (ret < 0)
|
|
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(&dentry->d_inode->i_mutex);
|
|
|
|
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);
|
|
}
|
|
mutex_lock(&dentry->d_inode->i_mutex);
|
|
out:
|
|
return ret > 0 ? EIO : ret;
|
|
}
|
|
|
|
static 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)
|
|
{
|
|
vma->vm_ops = &btrfs_file_vm_ops;
|
|
file_accessed(filp);
|
|
return 0;
|
|
}
|
|
|
|
struct file_operations btrfs_file_operations = {
|
|
.llseek = generic_file_llseek,
|
|
.read = do_sync_read,
|
|
.aio_read = generic_file_aio_read,
|
|
.splice_read = generic_file_splice_read,
|
|
.write = btrfs_file_write,
|
|
.mmap = btrfs_file_mmap,
|
|
.open = generic_file_open,
|
|
.release = btrfs_release_file,
|
|
.fsync = btrfs_sync_file,
|
|
.unlocked_ioctl = btrfs_ioctl,
|
|
#ifdef CONFIG_COMPAT
|
|
.compat_ioctl = btrfs_ioctl,
|
|
#endif
|
|
};
|