![Linus Torvalds](/assets/img/avatar_default.png)
* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable: Btrfs: break out of shrink_delalloc earlier btrfs: fix not enough reserved space btrfs: fix dip leak Btrfs: make sure not to return overlapping extents to fiemap Btrfs: deal with short returns from copy_from_user Btrfs: fix regressions in copy_from_user handling
1421 lines
37 KiB
C
1421 lines
37 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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/* 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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struct iov_iter *i)
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{
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size_t copied = 0;
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int pg = 0;
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int offset = pos & (PAGE_CACHE_SIZE - 1);
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int total_copied = 0;
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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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}
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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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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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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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NULL);
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BUG_ON(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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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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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(GFP_NOFS);
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if (!split2)
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split2 = alloc_extent_map(GFP_NOFS);
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BUG_ON(!split || !split2);
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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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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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split->compress_type = em->compress_type;
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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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split->compress_type = em->compress_type;
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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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write_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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int btrfs_drop_extents(struct btrfs_trans_handle *trans, struct inode *inode,
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u64 start, u64 end, u64 *hint_byte, int drop_cache)
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{
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struct btrfs_root *root = BTRFS_I(inode)->root;
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struct extent_buffer *leaf;
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struct btrfs_file_extent_item *fi;
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struct btrfs_path *path;
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struct btrfs_key key;
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struct btrfs_key new_key;
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u64 search_start = start;
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u64 disk_bytenr = 0;
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u64 num_bytes = 0;
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u64 extent_offset = 0;
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u64 extent_end = 0;
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int del_nr = 0;
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int del_slot = 0;
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int extent_type;
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int recow;
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int ret;
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if (drop_cache)
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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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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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break;
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if (ret > 0 && path->slots[0] > 0 && search_start == start) {
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leaf = path->nodes[0];
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btrfs_item_key_to_cpu(leaf, &key, path->slots[0] - 1);
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if (key.objectid == inode->i_ino &&
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key.type == BTRFS_EXTENT_DATA_KEY)
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path->slots[0]--;
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}
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ret = 0;
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next_slot:
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leaf = path->nodes[0];
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if (path->slots[0] >= btrfs_header_nritems(leaf)) {
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BUG_ON(del_nr > 0);
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ret = btrfs_next_leaf(root, path);
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if (ret < 0)
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break;
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if (ret > 0) {
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ret = 0;
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break;
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}
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leaf = path->nodes[0];
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recow = 1;
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}
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btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
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if (key.objectid > inode->i_ino ||
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key.type > BTRFS_EXTENT_DATA_KEY || key.offset >= end)
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break;
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fi = btrfs_item_ptr(leaf, path->slots[0],
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struct btrfs_file_extent_item);
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extent_type = btrfs_file_extent_type(leaf, fi);
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if (extent_type == BTRFS_FILE_EXTENT_REG ||
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extent_type == BTRFS_FILE_EXTENT_PREALLOC) {
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disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
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num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
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extent_offset = btrfs_file_extent_offset(leaf, fi);
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extent_end = key.offset +
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btrfs_file_extent_num_bytes(leaf, fi);
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} else if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
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extent_end = key.offset +
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btrfs_file_extent_inline_len(leaf, fi);
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} else {
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WARN_ON(1);
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extent_end = search_start;
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}
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if (extent_end <= search_start) {
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path->slots[0]++;
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goto next_slot;
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}
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search_start = max(key.offset, start);
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if (recow) {
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btrfs_release_path(root, path);
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continue;
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}
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/*
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* | - range to drop - |
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* | -------- extent -------- |
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*/
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if (start > key.offset && end < extent_end) {
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BUG_ON(del_nr > 0);
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BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE);
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memcpy(&new_key, &key, sizeof(new_key));
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new_key.offset = start;
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ret = btrfs_duplicate_item(trans, root, path,
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&new_key);
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if (ret == -EAGAIN) {
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btrfs_release_path(root, path);
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continue;
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}
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if (ret < 0)
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break;
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leaf = path->nodes[0];
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fi = btrfs_item_ptr(leaf, path->slots[0] - 1,
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struct btrfs_file_extent_item);
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btrfs_set_file_extent_num_bytes(leaf, fi,
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start - key.offset);
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fi = btrfs_item_ptr(leaf, path->slots[0],
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struct btrfs_file_extent_item);
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extent_offset += start - key.offset;
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btrfs_set_file_extent_offset(leaf, fi, extent_offset);
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btrfs_set_file_extent_num_bytes(leaf, fi,
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extent_end - start);
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btrfs_mark_buffer_dirty(leaf);
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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, num_bytes, 0,
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root->root_key.objectid,
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new_key.objectid,
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start - extent_offset);
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BUG_ON(ret);
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*hint_byte = disk_bytenr;
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}
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key.offset = start;
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}
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/*
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* | ---- range to drop ----- |
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* | -------- extent -------- |
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*/
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if (start <= key.offset && end < extent_end) {
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BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE);
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memcpy(&new_key, &key, sizeof(new_key));
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new_key.offset = end;
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btrfs_set_item_key_safe(trans, root, path, &new_key);
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extent_offset += end - key.offset;
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btrfs_set_file_extent_offset(leaf, fi, extent_offset);
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btrfs_set_file_extent_num_bytes(leaf, fi,
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extent_end - end);
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btrfs_mark_buffer_dirty(leaf);
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if (disk_bytenr > 0) {
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inode_sub_bytes(inode, end - key.offset);
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*hint_byte = disk_bytenr;
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}
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break;
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}
|
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|
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search_start = extent_end;
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/*
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* | ---- range to drop ----- |
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* | -------- extent -------- |
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*/
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if (start > key.offset && end >= extent_end) {
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BUG_ON(del_nr > 0);
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BUG_ON(extent_type == BTRFS_FILE_EXTENT_INLINE);
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|
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btrfs_set_file_extent_num_bytes(leaf, fi,
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start - key.offset);
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btrfs_mark_buffer_dirty(leaf);
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if (disk_bytenr > 0) {
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inode_sub_bytes(inode, extent_end - start);
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*hint_byte = disk_bytenr;
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}
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if (end == extent_end)
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break;
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path->slots[0]++;
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goto next_slot;
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}
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|
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/*
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* | ---- range to drop ----- |
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* | ------ extent ------ |
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*/
|
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if (start <= key.offset && end >= extent_end) {
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if (del_nr == 0) {
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del_slot = path->slots[0];
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del_nr = 1;
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} else {
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BUG_ON(del_slot + del_nr != path->slots[0]);
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del_nr++;
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}
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|
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if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
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inode_sub_bytes(inode,
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extent_end - key.offset);
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extent_end = ALIGN(extent_end,
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root->sectorsize);
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} else if (disk_bytenr > 0) {
|
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ret = btrfs_free_extent(trans, root,
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disk_bytenr, num_bytes, 0,
|
|
root->root_key.objectid,
|
|
key.objectid, key.offset -
|
|
extent_offset);
|
|
BUG_ON(ret);
|
|
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);
|
|
BUG_ON(ret);
|
|
|
|
del_nr = 0;
|
|
del_slot = 0;
|
|
|
|
btrfs_release_path(root, path);
|
|
continue;
|
|
}
|
|
|
|
BUG_ON(1);
|
|
}
|
|
|
|
if (del_nr > 0) {
|
|
ret = btrfs_del_items(trans, root, path, del_slot, del_nr);
|
|
BUG_ON(ret);
|
|
}
|
|
|
|
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;
|
|
|
|
btrfs_drop_extent_cache(inode, start, end - 1, 0);
|
|
|
|
path = btrfs_alloc_path();
|
|
BUG_ON(!path);
|
|
again:
|
|
recow = 0;
|
|
split = start;
|
|
key.objectid = inode->i_ino;
|
|
key.type = BTRFS_EXTENT_DATA_KEY;
|
|
key.offset = split;
|
|
|
|
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);
|
|
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,
|
|
inode->i_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,
|
|
inode->i_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(root, path);
|
|
goto again;
|
|
}
|
|
BUG_ON(ret < 0);
|
|
|
|
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,
|
|
inode->i_ino, orig_offset);
|
|
BUG_ON(ret);
|
|
|
|
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,
|
|
inode->i_ino, bytenr, orig_offset,
|
|
&other_start, &other_end)) {
|
|
if (recow) {
|
|
btrfs_release_path(root, 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,
|
|
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, orig_offset,
|
|
&other_start, &other_end)) {
|
|
if (recow) {
|
|
btrfs_release_path(root, 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,
|
|
inode->i_ino, orig_offset);
|
|
BUG_ON(ret);
|
|
}
|
|
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);
|
|
BUG_ON(ret);
|
|
}
|
|
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)
|
|
{
|
|
int ret = 0;
|
|
|
|
if ((pos & (PAGE_CACHE_SIZE - 1)) && !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,
|
|
unsigned long last_index, size_t write_bytes)
|
|
{
|
|
struct extent_state *cached_state = NULL;
|
|
int i;
|
|
unsigned long index = pos >> PAGE_CACHE_SHIFT;
|
|
struct inode *inode = fdentry(file)->d_inode;
|
|
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;
|
|
|
|
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]) {
|
|
faili = i - 1;
|
|
err = -ENOMEM;
|
|
goto fail;
|
|
}
|
|
|
|
if (i == 0)
|
|
err = prepare_uptodate_page(pages[i], pos);
|
|
if (i == num_pages - 1)
|
|
err = prepare_uptodate_page(pages[i],
|
|
pos + write_bytes);
|
|
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,
|
|
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_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++) {
|
|
clear_page_dirty_for_io(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 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;
|
|
struct page **pages = NULL;
|
|
struct iov_iter i;
|
|
loff_t *ppos = &iocb->ki_pos;
|
|
loff_t start_pos;
|
|
ssize_t num_written = 0;
|
|
ssize_t err = 0;
|
|
size_t count;
|
|
size_t ocount;
|
|
int ret = 0;
|
|
int nrptrs;
|
|
unsigned long first_index;
|
|
unsigned long last_index;
|
|
int will_write;
|
|
int buffered = 0;
|
|
int copied = 0;
|
|
int dirty_pages = 0;
|
|
|
|
will_write = ((file->f_flags & O_DSYNC) || IS_SYNC(inode) ||
|
|
(file->f_flags & O_DIRECT));
|
|
|
|
start_pos = pos;
|
|
|
|
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)
|
|
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)
|
|
goto out;
|
|
|
|
if (count == 0)
|
|
goto out;
|
|
|
|
err = file_remove_suid(file);
|
|
if (err)
|
|
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) {
|
|
err = -EROFS;
|
|
goto out;
|
|
}
|
|
|
|
file_update_time(file);
|
|
BTRFS_I(inode)->sequence++;
|
|
|
|
if (unlikely(file->f_flags & O_DIRECT)) {
|
|
num_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 (num_written < 0) {
|
|
ret = num_written;
|
|
num_written = 0;
|
|
goto out;
|
|
} else if (num_written == count) {
|
|
/* pick up pos changes done by the generic code */
|
|
pos = *ppos;
|
|
goto out;
|
|
}
|
|
/*
|
|
* We are going to do buffered for the rest of the range, so we
|
|
* need to make sure to invalidate the buffered pages when we're
|
|
* done.
|
|
*/
|
|
buffered = 1;
|
|
pos += num_written;
|
|
}
|
|
|
|
iov_iter_init(&i, iov, nr_segs, count, num_written);
|
|
nrptrs = min((iov_iter_count(&i) + PAGE_CACHE_SIZE - 1) /
|
|
PAGE_CACHE_SIZE, PAGE_CACHE_SIZE /
|
|
(sizeof(struct page *)));
|
|
pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL);
|
|
if (!pages) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
/* generic_write_checks can change our pos */
|
|
start_pos = pos;
|
|
|
|
first_index = pos >> PAGE_CACHE_SHIFT;
|
|
last_index = (pos + iov_iter_count(&i)) >> 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;
|
|
|
|
WARN_ON(num_pages > nrptrs);
|
|
memset(pages, 0, sizeof(struct page *) * 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;
|
|
goto out;
|
|
}
|
|
|
|
ret = btrfs_delalloc_reserve_space(inode,
|
|
num_pages << PAGE_CACHE_SHIFT);
|
|
if (ret)
|
|
goto out;
|
|
|
|
ret = prepare_pages(root, file, pages, num_pages,
|
|
pos, first_index, last_index,
|
|
write_bytes);
|
|
if (ret) {
|
|
btrfs_delalloc_release_space(inode,
|
|
num_pages << PAGE_CACHE_SHIFT);
|
|
goto out;
|
|
}
|
|
|
|
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)
|
|
dirty_pages = 0;
|
|
else
|
|
dirty_pages = (copied + offset +
|
|
PAGE_CACHE_SIZE - 1) >>
|
|
PAGE_CACHE_SHIFT;
|
|
|
|
if (num_pages > dirty_pages) {
|
|
if (copied > 0)
|
|
atomic_inc(
|
|
&BTRFS_I(inode)->outstanding_extents);
|
|
btrfs_delalloc_release_space(inode,
|
|
(num_pages - dirty_pages) <<
|
|
PAGE_CACHE_SHIFT);
|
|
}
|
|
|
|
if (copied > 0) {
|
|
dirty_and_release_pages(NULL, root, file, pages,
|
|
dirty_pages, pos, copied);
|
|
}
|
|
|
|
btrfs_drop_pages(pages, num_pages);
|
|
|
|
if (copied > 0) {
|
|
if (will_write) {
|
|
filemap_fdatawrite_range(inode->i_mapping, pos,
|
|
pos + copied - 1);
|
|
} else {
|
|
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);
|
|
btrfs_throttle(root);
|
|
}
|
|
}
|
|
|
|
pos += copied;
|
|
num_written += copied;
|
|
|
|
cond_resched();
|
|
}
|
|
out:
|
|
mutex_unlock(&inode->i_mutex);
|
|
if (ret)
|
|
err = ret;
|
|
|
|
kfree(pages);
|
|
*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_DSYNC) || IS_SYNC(inode)) {
|
|
trans = btrfs_start_transaction(root, 0);
|
|
if (IS_ERR(trans)) {
|
|
num_written = PTR_ERR(trans);
|
|
goto done;
|
|
}
|
|
mutex_lock(&inode->i_mutex);
|
|
ret = btrfs_log_dentry_safe(trans, root,
|
|
file->f_dentry);
|
|
mutex_unlock(&inode->i_mutex);
|
|
if (ret == 0) {
|
|
ret = btrfs_sync_log(trans, root);
|
|
if (ret == 0)
|
|
btrfs_end_transaction(trans, root);
|
|
else
|
|
btrfs_commit_transaction(trans, root);
|
|
} else if (ret != BTRFS_NO_LOG_SYNC) {
|
|
btrfs_commit_transaction(trans, root);
|
|
} else {
|
|
btrfs_end_transaction(trans, root);
|
|
}
|
|
}
|
|
if (file->f_flags & O_DIRECT && buffered) {
|
|
invalidate_mapping_pages(inode->i_mapping,
|
|
start_pos >> PAGE_CACHE_SHIFT,
|
|
(start_pos + num_written - 1) >> PAGE_CACHE_SHIFT);
|
|
}
|
|
}
|
|
done:
|
|
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, 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;
|
|
|
|
|
|
/* we wait first, since the writeback may change the inode */
|
|
root->log_batch++;
|
|
/* the VFS called filemap_fdatawrite for us */
|
|
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)
|
|
goto out;
|
|
|
|
/*
|
|
* if the last transaction that changed this file was before
|
|
* the current transaction, we can bail out now without any
|
|
* syncing
|
|
*/
|
|
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);
|
|
|
|
/*
|
|
* 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);
|
|
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 != 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);
|
|
}
|
|
mutex_lock(&dentry->d_inode->i_mutex);
|
|
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;
|
|
|
|
/*
|
|
* 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, alloc_start);
|
|
if (ret)
|
|
goto out;
|
|
}
|
|
|
|
ret = btrfs_check_data_free_space(inode, alloc_end - 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, GFP_NOFS);
|
|
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) {
|
|
em = btrfs_get_extent(inode, NULL, 0, cur_offset,
|
|
alloc_end - cur_offset, 0);
|
|
BUG_ON(IS_ERR(em) || !em);
|
|
last_byte = min(extent_map_end(em), alloc_end);
|
|
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;
|
|
}
|
|
}
|
|
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);
|
|
|
|
btrfs_free_reserved_data_space(inode, alloc_end - alloc_start);
|
|
out:
|
|
mutex_unlock(&inode->i_mutex);
|
|
return ret;
|
|
}
|
|
|
|
const struct file_operations btrfs_file_operations = {
|
|
.llseek = generic_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
|
|
};
|