| 1 |
62 |
marcus.erl |
/**
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| 2 |
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* aops.c - NTFS kernel address space operations and page cache handling.
|
| 3 |
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* Part of the Linux-NTFS project.
|
| 4 |
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*
|
| 5 |
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* Copyright (c) 2001-2007 Anton Altaparmakov
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* Copyright (c) 2002 Richard Russon
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*
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| 8 |
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* This program/include file is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as published
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| 10 |
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* by the Free Software Foundation; either version 2 of the License, or
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| 11 |
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* (at your option) any later version.
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*
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| 13 |
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* This program/include file is distributed in the hope that it will be
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| 14 |
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* useful, but WITHOUT ANY WARRANTY; without even the implied warranty
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| 15 |
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* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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| 16 |
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* GNU General Public License for more details.
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| 17 |
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*
|
| 18 |
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* You should have received a copy of the GNU General Public License
|
| 19 |
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* along with this program (in the main directory of the Linux-NTFS
|
| 20 |
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* distribution in the file COPYING); if not, write to the Free Software
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| 21 |
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* Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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| 23 |
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| 24 |
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#include <linux/errno.h>
|
| 25 |
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#include <linux/fs.h>
|
| 26 |
|
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#include <linux/mm.h>
|
| 27 |
|
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#include <linux/pagemap.h>
|
| 28 |
|
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#include <linux/swap.h>
|
| 29 |
|
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#include <linux/buffer_head.h>
|
| 30 |
|
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#include <linux/writeback.h>
|
| 31 |
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#include <linux/bit_spinlock.h>
|
| 32 |
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|
| 33 |
|
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#include "aops.h"
|
| 34 |
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#include "attrib.h"
|
| 35 |
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#include "debug.h"
|
| 36 |
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#include "inode.h"
|
| 37 |
|
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#include "mft.h"
|
| 38 |
|
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#include "runlist.h"
|
| 39 |
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#include "types.h"
|
| 40 |
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#include "ntfs.h"
|
| 41 |
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| 42 |
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/**
|
| 43 |
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* ntfs_end_buffer_async_read - async io completion for reading attributes
|
| 44 |
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* @bh: buffer head on which io is completed
|
| 45 |
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* @uptodate: whether @bh is now uptodate or not
|
| 46 |
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*
|
| 47 |
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* Asynchronous I/O completion handler for reading pages belonging to the
|
| 48 |
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* attribute address space of an inode. The inodes can either be files or
|
| 49 |
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* directories or they can be fake inodes describing some attribute.
|
| 50 |
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*
|
| 51 |
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* If NInoMstProtected(), perform the post read mst fixups when all IO on the
|
| 52 |
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* page has been completed and mark the page uptodate or set the error bit on
|
| 53 |
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* the page. To determine the size of the records that need fixing up, we
|
| 54 |
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* cheat a little bit by setting the index_block_size in ntfs_inode to the ntfs
|
| 55 |
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* record size, and index_block_size_bits, to the log(base 2) of the ntfs
|
| 56 |
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* record size.
|
| 57 |
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*/
|
| 58 |
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static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate)
|
| 59 |
|
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{
|
| 60 |
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unsigned long flags;
|
| 61 |
|
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struct buffer_head *first, *tmp;
|
| 62 |
|
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struct page *page;
|
| 63 |
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struct inode *vi;
|
| 64 |
|
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ntfs_inode *ni;
|
| 65 |
|
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int page_uptodate = 1;
|
| 66 |
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|
| 67 |
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page = bh->b_page;
|
| 68 |
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vi = page->mapping->host;
|
| 69 |
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ni = NTFS_I(vi);
|
| 70 |
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|
| 71 |
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if (likely(uptodate)) {
|
| 72 |
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loff_t i_size;
|
| 73 |
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s64 file_ofs, init_size;
|
| 74 |
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|
| 75 |
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set_buffer_uptodate(bh);
|
| 76 |
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|
|
| 77 |
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file_ofs = ((s64)page->index << PAGE_CACHE_SHIFT) +
|
| 78 |
|
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bh_offset(bh);
|
| 79 |
|
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read_lock_irqsave(&ni->size_lock, flags);
|
| 80 |
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init_size = ni->initialized_size;
|
| 81 |
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i_size = i_size_read(vi);
|
| 82 |
|
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read_unlock_irqrestore(&ni->size_lock, flags);
|
| 83 |
|
|
if (unlikely(init_size > i_size)) {
|
| 84 |
|
|
/* Race with shrinking truncate. */
|
| 85 |
|
|
init_size = i_size;
|
| 86 |
|
|
}
|
| 87 |
|
|
/* Check for the current buffer head overflowing. */
|
| 88 |
|
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if (unlikely(file_ofs + bh->b_size > init_size)) {
|
| 89 |
|
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int ofs;
|
| 90 |
|
|
|
| 91 |
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ofs = 0;
|
| 92 |
|
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if (file_ofs < init_size)
|
| 93 |
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ofs = init_size - file_ofs;
|
| 94 |
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local_irq_save(flags);
|
| 95 |
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zero_user_page(page, bh_offset(bh) + ofs,
|
| 96 |
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|
bh->b_size - ofs, KM_BIO_SRC_IRQ);
|
| 97 |
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local_irq_restore(flags);
|
| 98 |
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}
|
| 99 |
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} else {
|
| 100 |
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clear_buffer_uptodate(bh);
|
| 101 |
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SetPageError(page);
|
| 102 |
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ntfs_error(ni->vol->sb, "Buffer I/O error, logical block "
|
| 103 |
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"0x%llx.", (unsigned long long)bh->b_blocknr);
|
| 104 |
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}
|
| 105 |
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first = page_buffers(page);
|
| 106 |
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local_irq_save(flags);
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| 107 |
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bit_spin_lock(BH_Uptodate_Lock, &first->b_state);
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| 108 |
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clear_buffer_async_read(bh);
|
| 109 |
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unlock_buffer(bh);
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| 110 |
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tmp = bh;
|
| 111 |
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do {
|
| 112 |
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if (!buffer_uptodate(tmp))
|
| 113 |
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page_uptodate = 0;
|
| 114 |
|
|
if (buffer_async_read(tmp)) {
|
| 115 |
|
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if (likely(buffer_locked(tmp)))
|
| 116 |
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goto still_busy;
|
| 117 |
|
|
/* Async buffers must be locked. */
|
| 118 |
|
|
BUG();
|
| 119 |
|
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}
|
| 120 |
|
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tmp = tmp->b_this_page;
|
| 121 |
|
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} while (tmp != bh);
|
| 122 |
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bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
|
| 123 |
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local_irq_restore(flags);
|
| 124 |
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/*
|
| 125 |
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* If none of the buffers had errors then we can set the page uptodate,
|
| 126 |
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* but we first have to perform the post read mst fixups, if the
|
| 127 |
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* attribute is mst protected, i.e. if NInoMstProteced(ni) is true.
|
| 128 |
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* Note we ignore fixup errors as those are detected when
|
| 129 |
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* map_mft_record() is called which gives us per record granularity
|
| 130 |
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* rather than per page granularity.
|
| 131 |
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*/
|
| 132 |
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|
if (!NInoMstProtected(ni)) {
|
| 133 |
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if (likely(page_uptodate && !PageError(page)))
|
| 134 |
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SetPageUptodate(page);
|
| 135 |
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} else {
|
| 136 |
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u8 *kaddr;
|
| 137 |
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unsigned int i, recs;
|
| 138 |
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u32 rec_size;
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| 139 |
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| 140 |
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rec_size = ni->itype.index.block_size;
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| 141 |
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recs = PAGE_CACHE_SIZE / rec_size;
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| 142 |
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/* Should have been verified before we got here... */
|
| 143 |
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BUG_ON(!recs);
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| 144 |
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local_irq_save(flags);
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| 145 |
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kaddr = kmap_atomic(page, KM_BIO_SRC_IRQ);
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| 146 |
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for (i = 0; i < recs; i++)
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| 147 |
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post_read_mst_fixup((NTFS_RECORD*)(kaddr +
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| 148 |
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i * rec_size), rec_size);
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| 149 |
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kunmap_atomic(kaddr, KM_BIO_SRC_IRQ);
|
| 150 |
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local_irq_restore(flags);
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| 151 |
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flush_dcache_page(page);
|
| 152 |
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if (likely(page_uptodate && !PageError(page)))
|
| 153 |
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SetPageUptodate(page);
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| 154 |
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}
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| 155 |
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unlock_page(page);
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| 156 |
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return;
|
| 157 |
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still_busy:
|
| 158 |
|
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bit_spin_unlock(BH_Uptodate_Lock, &first->b_state);
|
| 159 |
|
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local_irq_restore(flags);
|
| 160 |
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return;
|
| 161 |
|
|
}
|
| 162 |
|
|
|
| 163 |
|
|
/**
|
| 164 |
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* ntfs_read_block - fill a @page of an address space with data
|
| 165 |
|
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* @page: page cache page to fill with data
|
| 166 |
|
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*
|
| 167 |
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* Fill the page @page of the address space belonging to the @page->host inode.
|
| 168 |
|
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* We read each buffer asynchronously and when all buffers are read in, our io
|
| 169 |
|
|
* completion handler ntfs_end_buffer_read_async(), if required, automatically
|
| 170 |
|
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* applies the mst fixups to the page before finally marking it uptodate and
|
| 171 |
|
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* unlocking it.
|
| 172 |
|
|
*
|
| 173 |
|
|
* We only enforce allocated_size limit because i_size is checked for in
|
| 174 |
|
|
* generic_file_read().
|
| 175 |
|
|
*
|
| 176 |
|
|
* Return 0 on success and -errno on error.
|
| 177 |
|
|
*
|
| 178 |
|
|
* Contains an adapted version of fs/buffer.c::block_read_full_page().
|
| 179 |
|
|
*/
|
| 180 |
|
|
static int ntfs_read_block(struct page *page)
|
| 181 |
|
|
{
|
| 182 |
|
|
loff_t i_size;
|
| 183 |
|
|
VCN vcn;
|
| 184 |
|
|
LCN lcn;
|
| 185 |
|
|
s64 init_size;
|
| 186 |
|
|
struct inode *vi;
|
| 187 |
|
|
ntfs_inode *ni;
|
| 188 |
|
|
ntfs_volume *vol;
|
| 189 |
|
|
runlist_element *rl;
|
| 190 |
|
|
struct buffer_head *bh, *head, *arr[MAX_BUF_PER_PAGE];
|
| 191 |
|
|
sector_t iblock, lblock, zblock;
|
| 192 |
|
|
unsigned long flags;
|
| 193 |
|
|
unsigned int blocksize, vcn_ofs;
|
| 194 |
|
|
int i, nr;
|
| 195 |
|
|
unsigned char blocksize_bits;
|
| 196 |
|
|
|
| 197 |
|
|
vi = page->mapping->host;
|
| 198 |
|
|
ni = NTFS_I(vi);
|
| 199 |
|
|
vol = ni->vol;
|
| 200 |
|
|
|
| 201 |
|
|
/* $MFT/$DATA must have its complete runlist in memory at all times. */
|
| 202 |
|
|
BUG_ON(!ni->runlist.rl && !ni->mft_no && !NInoAttr(ni));
|
| 203 |
|
|
|
| 204 |
|
|
blocksize = vol->sb->s_blocksize;
|
| 205 |
|
|
blocksize_bits = vol->sb->s_blocksize_bits;
|
| 206 |
|
|
|
| 207 |
|
|
if (!page_has_buffers(page)) {
|
| 208 |
|
|
create_empty_buffers(page, blocksize, 0);
|
| 209 |
|
|
if (unlikely(!page_has_buffers(page))) {
|
| 210 |
|
|
unlock_page(page);
|
| 211 |
|
|
return -ENOMEM;
|
| 212 |
|
|
}
|
| 213 |
|
|
}
|
| 214 |
|
|
bh = head = page_buffers(page);
|
| 215 |
|
|
BUG_ON(!bh);
|
| 216 |
|
|
|
| 217 |
|
|
/*
|
| 218 |
|
|
* We may be racing with truncate. To avoid some of the problems we
|
| 219 |
|
|
* now take a snapshot of the various sizes and use those for the whole
|
| 220 |
|
|
* of the function. In case of an extending truncate it just means we
|
| 221 |
|
|
* may leave some buffers unmapped which are now allocated. This is
|
| 222 |
|
|
* not a problem since these buffers will just get mapped when a write
|
| 223 |
|
|
* occurs. In case of a shrinking truncate, we will detect this later
|
| 224 |
|
|
* on due to the runlist being incomplete and if the page is being
|
| 225 |
|
|
* fully truncated, truncate will throw it away as soon as we unlock
|
| 226 |
|
|
* it so no need to worry what we do with it.
|
| 227 |
|
|
*/
|
| 228 |
|
|
iblock = (s64)page->index << (PAGE_CACHE_SHIFT - blocksize_bits);
|
| 229 |
|
|
read_lock_irqsave(&ni->size_lock, flags);
|
| 230 |
|
|
lblock = (ni->allocated_size + blocksize - 1) >> blocksize_bits;
|
| 231 |
|
|
init_size = ni->initialized_size;
|
| 232 |
|
|
i_size = i_size_read(vi);
|
| 233 |
|
|
read_unlock_irqrestore(&ni->size_lock, flags);
|
| 234 |
|
|
if (unlikely(init_size > i_size)) {
|
| 235 |
|
|
/* Race with shrinking truncate. */
|
| 236 |
|
|
init_size = i_size;
|
| 237 |
|
|
}
|
| 238 |
|
|
zblock = (init_size + blocksize - 1) >> blocksize_bits;
|
| 239 |
|
|
|
| 240 |
|
|
/* Loop through all the buffers in the page. */
|
| 241 |
|
|
rl = NULL;
|
| 242 |
|
|
nr = i = 0;
|
| 243 |
|
|
do {
|
| 244 |
|
|
int err = 0;
|
| 245 |
|
|
|
| 246 |
|
|
if (unlikely(buffer_uptodate(bh)))
|
| 247 |
|
|
continue;
|
| 248 |
|
|
if (unlikely(buffer_mapped(bh))) {
|
| 249 |
|
|
arr[nr++] = bh;
|
| 250 |
|
|
continue;
|
| 251 |
|
|
}
|
| 252 |
|
|
bh->b_bdev = vol->sb->s_bdev;
|
| 253 |
|
|
/* Is the block within the allowed limits? */
|
| 254 |
|
|
if (iblock < lblock) {
|
| 255 |
|
|
bool is_retry = false;
|
| 256 |
|
|
|
| 257 |
|
|
/* Convert iblock into corresponding vcn and offset. */
|
| 258 |
|
|
vcn = (VCN)iblock << blocksize_bits >>
|
| 259 |
|
|
vol->cluster_size_bits;
|
| 260 |
|
|
vcn_ofs = ((VCN)iblock << blocksize_bits) &
|
| 261 |
|
|
vol->cluster_size_mask;
|
| 262 |
|
|
if (!rl) {
|
| 263 |
|
|
lock_retry_remap:
|
| 264 |
|
|
down_read(&ni->runlist.lock);
|
| 265 |
|
|
rl = ni->runlist.rl;
|
| 266 |
|
|
}
|
| 267 |
|
|
if (likely(rl != NULL)) {
|
| 268 |
|
|
/* Seek to element containing target vcn. */
|
| 269 |
|
|
while (rl->length && rl[1].vcn <= vcn)
|
| 270 |
|
|
rl++;
|
| 271 |
|
|
lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
|
| 272 |
|
|
} else
|
| 273 |
|
|
lcn = LCN_RL_NOT_MAPPED;
|
| 274 |
|
|
/* Successful remap. */
|
| 275 |
|
|
if (lcn >= 0) {
|
| 276 |
|
|
/* Setup buffer head to correct block. */
|
| 277 |
|
|
bh->b_blocknr = ((lcn << vol->cluster_size_bits)
|
| 278 |
|
|
+ vcn_ofs) >> blocksize_bits;
|
| 279 |
|
|
set_buffer_mapped(bh);
|
| 280 |
|
|
/* Only read initialized data blocks. */
|
| 281 |
|
|
if (iblock < zblock) {
|
| 282 |
|
|
arr[nr++] = bh;
|
| 283 |
|
|
continue;
|
| 284 |
|
|
}
|
| 285 |
|
|
/* Fully non-initialized data block, zero it. */
|
| 286 |
|
|
goto handle_zblock;
|
| 287 |
|
|
}
|
| 288 |
|
|
/* It is a hole, need to zero it. */
|
| 289 |
|
|
if (lcn == LCN_HOLE)
|
| 290 |
|
|
goto handle_hole;
|
| 291 |
|
|
/* If first try and runlist unmapped, map and retry. */
|
| 292 |
|
|
if (!is_retry && lcn == LCN_RL_NOT_MAPPED) {
|
| 293 |
|
|
is_retry = true;
|
| 294 |
|
|
/*
|
| 295 |
|
|
* Attempt to map runlist, dropping lock for
|
| 296 |
|
|
* the duration.
|
| 297 |
|
|
*/
|
| 298 |
|
|
up_read(&ni->runlist.lock);
|
| 299 |
|
|
err = ntfs_map_runlist(ni, vcn);
|
| 300 |
|
|
if (likely(!err))
|
| 301 |
|
|
goto lock_retry_remap;
|
| 302 |
|
|
rl = NULL;
|
| 303 |
|
|
} else if (!rl)
|
| 304 |
|
|
up_read(&ni->runlist.lock);
|
| 305 |
|
|
/*
|
| 306 |
|
|
* If buffer is outside the runlist, treat it as a
|
| 307 |
|
|
* hole. This can happen due to concurrent truncate
|
| 308 |
|
|
* for example.
|
| 309 |
|
|
*/
|
| 310 |
|
|
if (err == -ENOENT || lcn == LCN_ENOENT) {
|
| 311 |
|
|
err = 0;
|
| 312 |
|
|
goto handle_hole;
|
| 313 |
|
|
}
|
| 314 |
|
|
/* Hard error, zero out region. */
|
| 315 |
|
|
if (!err)
|
| 316 |
|
|
err = -EIO;
|
| 317 |
|
|
bh->b_blocknr = -1;
|
| 318 |
|
|
SetPageError(page);
|
| 319 |
|
|
ntfs_error(vol->sb, "Failed to read from inode 0x%lx, "
|
| 320 |
|
|
"attribute type 0x%x, vcn 0x%llx, "
|
| 321 |
|
|
"offset 0x%x because its location on "
|
| 322 |
|
|
"disk could not be determined%s "
|
| 323 |
|
|
"(error code %i).", ni->mft_no,
|
| 324 |
|
|
ni->type, (unsigned long long)vcn,
|
| 325 |
|
|
vcn_ofs, is_retry ? " even after "
|
| 326 |
|
|
"retrying" : "", err);
|
| 327 |
|
|
}
|
| 328 |
|
|
/*
|
| 329 |
|
|
* Either iblock was outside lblock limits or
|
| 330 |
|
|
* ntfs_rl_vcn_to_lcn() returned error. Just zero that portion
|
| 331 |
|
|
* of the page and set the buffer uptodate.
|
| 332 |
|
|
*/
|
| 333 |
|
|
handle_hole:
|
| 334 |
|
|
bh->b_blocknr = -1UL;
|
| 335 |
|
|
clear_buffer_mapped(bh);
|
| 336 |
|
|
handle_zblock:
|
| 337 |
|
|
zero_user_page(page, i * blocksize, blocksize, KM_USER0);
|
| 338 |
|
|
if (likely(!err))
|
| 339 |
|
|
set_buffer_uptodate(bh);
|
| 340 |
|
|
} while (i++, iblock++, (bh = bh->b_this_page) != head);
|
| 341 |
|
|
|
| 342 |
|
|
/* Release the lock if we took it. */
|
| 343 |
|
|
if (rl)
|
| 344 |
|
|
up_read(&ni->runlist.lock);
|
| 345 |
|
|
|
| 346 |
|
|
/* Check we have at least one buffer ready for i/o. */
|
| 347 |
|
|
if (nr) {
|
| 348 |
|
|
struct buffer_head *tbh;
|
| 349 |
|
|
|
| 350 |
|
|
/* Lock the buffers. */
|
| 351 |
|
|
for (i = 0; i < nr; i++) {
|
| 352 |
|
|
tbh = arr[i];
|
| 353 |
|
|
lock_buffer(tbh);
|
| 354 |
|
|
tbh->b_end_io = ntfs_end_buffer_async_read;
|
| 355 |
|
|
set_buffer_async_read(tbh);
|
| 356 |
|
|
}
|
| 357 |
|
|
/* Finally, start i/o on the buffers. */
|
| 358 |
|
|
for (i = 0; i < nr; i++) {
|
| 359 |
|
|
tbh = arr[i];
|
| 360 |
|
|
if (likely(!buffer_uptodate(tbh)))
|
| 361 |
|
|
submit_bh(READ, tbh);
|
| 362 |
|
|
else
|
| 363 |
|
|
ntfs_end_buffer_async_read(tbh, 1);
|
| 364 |
|
|
}
|
| 365 |
|
|
return 0;
|
| 366 |
|
|
}
|
| 367 |
|
|
/* No i/o was scheduled on any of the buffers. */
|
| 368 |
|
|
if (likely(!PageError(page)))
|
| 369 |
|
|
SetPageUptodate(page);
|
| 370 |
|
|
else /* Signal synchronous i/o error. */
|
| 371 |
|
|
nr = -EIO;
|
| 372 |
|
|
unlock_page(page);
|
| 373 |
|
|
return nr;
|
| 374 |
|
|
}
|
| 375 |
|
|
|
| 376 |
|
|
/**
|
| 377 |
|
|
* ntfs_readpage - fill a @page of a @file with data from the device
|
| 378 |
|
|
* @file: open file to which the page @page belongs or NULL
|
| 379 |
|
|
* @page: page cache page to fill with data
|
| 380 |
|
|
*
|
| 381 |
|
|
* For non-resident attributes, ntfs_readpage() fills the @page of the open
|
| 382 |
|
|
* file @file by calling the ntfs version of the generic block_read_full_page()
|
| 383 |
|
|
* function, ntfs_read_block(), which in turn creates and reads in the buffers
|
| 384 |
|
|
* associated with the page asynchronously.
|
| 385 |
|
|
*
|
| 386 |
|
|
* For resident attributes, OTOH, ntfs_readpage() fills @page by copying the
|
| 387 |
|
|
* data from the mft record (which at this stage is most likely in memory) and
|
| 388 |
|
|
* fills the remainder with zeroes. Thus, in this case, I/O is synchronous, as
|
| 389 |
|
|
* even if the mft record is not cached at this point in time, we need to wait
|
| 390 |
|
|
* for it to be read in before we can do the copy.
|
| 391 |
|
|
*
|
| 392 |
|
|
* Return 0 on success and -errno on error.
|
| 393 |
|
|
*/
|
| 394 |
|
|
static int ntfs_readpage(struct file *file, struct page *page)
|
| 395 |
|
|
{
|
| 396 |
|
|
loff_t i_size;
|
| 397 |
|
|
struct inode *vi;
|
| 398 |
|
|
ntfs_inode *ni, *base_ni;
|
| 399 |
|
|
u8 *addr;
|
| 400 |
|
|
ntfs_attr_search_ctx *ctx;
|
| 401 |
|
|
MFT_RECORD *mrec;
|
| 402 |
|
|
unsigned long flags;
|
| 403 |
|
|
u32 attr_len;
|
| 404 |
|
|
int err = 0;
|
| 405 |
|
|
|
| 406 |
|
|
retry_readpage:
|
| 407 |
|
|
BUG_ON(!PageLocked(page));
|
| 408 |
|
|
vi = page->mapping->host;
|
| 409 |
|
|
i_size = i_size_read(vi);
|
| 410 |
|
|
/* Is the page fully outside i_size? (truncate in progress) */
|
| 411 |
|
|
if (unlikely(page->index >= (i_size + PAGE_CACHE_SIZE - 1) >>
|
| 412 |
|
|
PAGE_CACHE_SHIFT)) {
|
| 413 |
|
|
zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0);
|
| 414 |
|
|
ntfs_debug("Read outside i_size - truncated?");
|
| 415 |
|
|
goto done;
|
| 416 |
|
|
}
|
| 417 |
|
|
/*
|
| 418 |
|
|
* This can potentially happen because we clear PageUptodate() during
|
| 419 |
|
|
* ntfs_writepage() of MstProtected() attributes.
|
| 420 |
|
|
*/
|
| 421 |
|
|
if (PageUptodate(page)) {
|
| 422 |
|
|
unlock_page(page);
|
| 423 |
|
|
return 0;
|
| 424 |
|
|
}
|
| 425 |
|
|
ni = NTFS_I(vi);
|
| 426 |
|
|
/*
|
| 427 |
|
|
* Only $DATA attributes can be encrypted and only unnamed $DATA
|
| 428 |
|
|
* attributes can be compressed. Index root can have the flags set but
|
| 429 |
|
|
* this means to create compressed/encrypted files, not that the
|
| 430 |
|
|
* attribute is compressed/encrypted. Note we need to check for
|
| 431 |
|
|
* AT_INDEX_ALLOCATION since this is the type of both directory and
|
| 432 |
|
|
* index inodes.
|
| 433 |
|
|
*/
|
| 434 |
|
|
if (ni->type != AT_INDEX_ALLOCATION) {
|
| 435 |
|
|
/* If attribute is encrypted, deny access, just like NT4. */
|
| 436 |
|
|
if (NInoEncrypted(ni)) {
|
| 437 |
|
|
BUG_ON(ni->type != AT_DATA);
|
| 438 |
|
|
err = -EACCES;
|
| 439 |
|
|
goto err_out;
|
| 440 |
|
|
}
|
| 441 |
|
|
/* Compressed data streams are handled in compress.c. */
|
| 442 |
|
|
if (NInoNonResident(ni) && NInoCompressed(ni)) {
|
| 443 |
|
|
BUG_ON(ni->type != AT_DATA);
|
| 444 |
|
|
BUG_ON(ni->name_len);
|
| 445 |
|
|
return ntfs_read_compressed_block(page);
|
| 446 |
|
|
}
|
| 447 |
|
|
}
|
| 448 |
|
|
/* NInoNonResident() == NInoIndexAllocPresent() */
|
| 449 |
|
|
if (NInoNonResident(ni)) {
|
| 450 |
|
|
/* Normal, non-resident data stream. */
|
| 451 |
|
|
return ntfs_read_block(page);
|
| 452 |
|
|
}
|
| 453 |
|
|
/*
|
| 454 |
|
|
* Attribute is resident, implying it is not compressed or encrypted.
|
| 455 |
|
|
* This also means the attribute is smaller than an mft record and
|
| 456 |
|
|
* hence smaller than a page, so can simply zero out any pages with
|
| 457 |
|
|
* index above 0. Note the attribute can actually be marked compressed
|
| 458 |
|
|
* but if it is resident the actual data is not compressed so we are
|
| 459 |
|
|
* ok to ignore the compressed flag here.
|
| 460 |
|
|
*/
|
| 461 |
|
|
if (unlikely(page->index > 0)) {
|
| 462 |
|
|
zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0);
|
| 463 |
|
|
goto done;
|
| 464 |
|
|
}
|
| 465 |
|
|
if (!NInoAttr(ni))
|
| 466 |
|
|
base_ni = ni;
|
| 467 |
|
|
else
|
| 468 |
|
|
base_ni = ni->ext.base_ntfs_ino;
|
| 469 |
|
|
/* Map, pin, and lock the mft record. */
|
| 470 |
|
|
mrec = map_mft_record(base_ni);
|
| 471 |
|
|
if (IS_ERR(mrec)) {
|
| 472 |
|
|
err = PTR_ERR(mrec);
|
| 473 |
|
|
goto err_out;
|
| 474 |
|
|
}
|
| 475 |
|
|
/*
|
| 476 |
|
|
* If a parallel write made the attribute non-resident, drop the mft
|
| 477 |
|
|
* record and retry the readpage.
|
| 478 |
|
|
*/
|
| 479 |
|
|
if (unlikely(NInoNonResident(ni))) {
|
| 480 |
|
|
unmap_mft_record(base_ni);
|
| 481 |
|
|
goto retry_readpage;
|
| 482 |
|
|
}
|
| 483 |
|
|
ctx = ntfs_attr_get_search_ctx(base_ni, mrec);
|
| 484 |
|
|
if (unlikely(!ctx)) {
|
| 485 |
|
|
err = -ENOMEM;
|
| 486 |
|
|
goto unm_err_out;
|
| 487 |
|
|
}
|
| 488 |
|
|
err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
|
| 489 |
|
|
CASE_SENSITIVE, 0, NULL, 0, ctx);
|
| 490 |
|
|
if (unlikely(err))
|
| 491 |
|
|
goto put_unm_err_out;
|
| 492 |
|
|
attr_len = le32_to_cpu(ctx->attr->data.resident.value_length);
|
| 493 |
|
|
read_lock_irqsave(&ni->size_lock, flags);
|
| 494 |
|
|
if (unlikely(attr_len > ni->initialized_size))
|
| 495 |
|
|
attr_len = ni->initialized_size;
|
| 496 |
|
|
i_size = i_size_read(vi);
|
| 497 |
|
|
read_unlock_irqrestore(&ni->size_lock, flags);
|
| 498 |
|
|
if (unlikely(attr_len > i_size)) {
|
| 499 |
|
|
/* Race with shrinking truncate. */
|
| 500 |
|
|
attr_len = i_size;
|
| 501 |
|
|
}
|
| 502 |
|
|
addr = kmap_atomic(page, KM_USER0);
|
| 503 |
|
|
/* Copy the data to the page. */
|
| 504 |
|
|
memcpy(addr, (u8*)ctx->attr +
|
| 505 |
|
|
le16_to_cpu(ctx->attr->data.resident.value_offset),
|
| 506 |
|
|
attr_len);
|
| 507 |
|
|
/* Zero the remainder of the page. */
|
| 508 |
|
|
memset(addr + attr_len, 0, PAGE_CACHE_SIZE - attr_len);
|
| 509 |
|
|
flush_dcache_page(page);
|
| 510 |
|
|
kunmap_atomic(addr, KM_USER0);
|
| 511 |
|
|
put_unm_err_out:
|
| 512 |
|
|
ntfs_attr_put_search_ctx(ctx);
|
| 513 |
|
|
unm_err_out:
|
| 514 |
|
|
unmap_mft_record(base_ni);
|
| 515 |
|
|
done:
|
| 516 |
|
|
SetPageUptodate(page);
|
| 517 |
|
|
err_out:
|
| 518 |
|
|
unlock_page(page);
|
| 519 |
|
|
return err;
|
| 520 |
|
|
}
|
| 521 |
|
|
|
| 522 |
|
|
#ifdef NTFS_RW
|
| 523 |
|
|
|
| 524 |
|
|
/**
|
| 525 |
|
|
* ntfs_write_block - write a @page to the backing store
|
| 526 |
|
|
* @page: page cache page to write out
|
| 527 |
|
|
* @wbc: writeback control structure
|
| 528 |
|
|
*
|
| 529 |
|
|
* This function is for writing pages belonging to non-resident, non-mst
|
| 530 |
|
|
* protected attributes to their backing store.
|
| 531 |
|
|
*
|
| 532 |
|
|
* For a page with buffers, map and write the dirty buffers asynchronously
|
| 533 |
|
|
* under page writeback. For a page without buffers, create buffers for the
|
| 534 |
|
|
* page, then proceed as above.
|
| 535 |
|
|
*
|
| 536 |
|
|
* If a page doesn't have buffers the page dirty state is definitive. If a page
|
| 537 |
|
|
* does have buffers, the page dirty state is just a hint, and the buffer dirty
|
| 538 |
|
|
* state is definitive. (A hint which has rules: dirty buffers against a clean
|
| 539 |
|
|
* page is illegal. Other combinations are legal and need to be handled. In
|
| 540 |
|
|
* particular a dirty page containing clean buffers for example.)
|
| 541 |
|
|
*
|
| 542 |
|
|
* Return 0 on success and -errno on error.
|
| 543 |
|
|
*
|
| 544 |
|
|
* Based on ntfs_read_block() and __block_write_full_page().
|
| 545 |
|
|
*/
|
| 546 |
|
|
static int ntfs_write_block(struct page *page, struct writeback_control *wbc)
|
| 547 |
|
|
{
|
| 548 |
|
|
VCN vcn;
|
| 549 |
|
|
LCN lcn;
|
| 550 |
|
|
s64 initialized_size;
|
| 551 |
|
|
loff_t i_size;
|
| 552 |
|
|
sector_t block, dblock, iblock;
|
| 553 |
|
|
struct inode *vi;
|
| 554 |
|
|
ntfs_inode *ni;
|
| 555 |
|
|
ntfs_volume *vol;
|
| 556 |
|
|
runlist_element *rl;
|
| 557 |
|
|
struct buffer_head *bh, *head;
|
| 558 |
|
|
unsigned long flags;
|
| 559 |
|
|
unsigned int blocksize, vcn_ofs;
|
| 560 |
|
|
int err;
|
| 561 |
|
|
bool need_end_writeback;
|
| 562 |
|
|
unsigned char blocksize_bits;
|
| 563 |
|
|
|
| 564 |
|
|
vi = page->mapping->host;
|
| 565 |
|
|
ni = NTFS_I(vi);
|
| 566 |
|
|
vol = ni->vol;
|
| 567 |
|
|
|
| 568 |
|
|
ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index "
|
| 569 |
|
|
"0x%lx.", ni->mft_no, ni->type, page->index);
|
| 570 |
|
|
|
| 571 |
|
|
BUG_ON(!NInoNonResident(ni));
|
| 572 |
|
|
BUG_ON(NInoMstProtected(ni));
|
| 573 |
|
|
blocksize = vol->sb->s_blocksize;
|
| 574 |
|
|
blocksize_bits = vol->sb->s_blocksize_bits;
|
| 575 |
|
|
if (!page_has_buffers(page)) {
|
| 576 |
|
|
BUG_ON(!PageUptodate(page));
|
| 577 |
|
|
create_empty_buffers(page, blocksize,
|
| 578 |
|
|
(1 << BH_Uptodate) | (1 << BH_Dirty));
|
| 579 |
|
|
if (unlikely(!page_has_buffers(page))) {
|
| 580 |
|
|
ntfs_warning(vol->sb, "Error allocating page "
|
| 581 |
|
|
"buffers. Redirtying page so we try "
|
| 582 |
|
|
"again later.");
|
| 583 |
|
|
/*
|
| 584 |
|
|
* Put the page back on mapping->dirty_pages, but leave
|
| 585 |
|
|
* its buffers' dirty state as-is.
|
| 586 |
|
|
*/
|
| 587 |
|
|
redirty_page_for_writepage(wbc, page);
|
| 588 |
|
|
unlock_page(page);
|
| 589 |
|
|
return 0;
|
| 590 |
|
|
}
|
| 591 |
|
|
}
|
| 592 |
|
|
bh = head = page_buffers(page);
|
| 593 |
|
|
BUG_ON(!bh);
|
| 594 |
|
|
|
| 595 |
|
|
/* NOTE: Different naming scheme to ntfs_read_block()! */
|
| 596 |
|
|
|
| 597 |
|
|
/* The first block in the page. */
|
| 598 |
|
|
block = (s64)page->index << (PAGE_CACHE_SHIFT - blocksize_bits);
|
| 599 |
|
|
|
| 600 |
|
|
read_lock_irqsave(&ni->size_lock, flags);
|
| 601 |
|
|
i_size = i_size_read(vi);
|
| 602 |
|
|
initialized_size = ni->initialized_size;
|
| 603 |
|
|
read_unlock_irqrestore(&ni->size_lock, flags);
|
| 604 |
|
|
|
| 605 |
|
|
/* The first out of bounds block for the data size. */
|
| 606 |
|
|
dblock = (i_size + blocksize - 1) >> blocksize_bits;
|
| 607 |
|
|
|
| 608 |
|
|
/* The last (fully or partially) initialized block. */
|
| 609 |
|
|
iblock = initialized_size >> blocksize_bits;
|
| 610 |
|
|
|
| 611 |
|
|
/*
|
| 612 |
|
|
* Be very careful. We have no exclusion from __set_page_dirty_buffers
|
| 613 |
|
|
* here, and the (potentially unmapped) buffers may become dirty at
|
| 614 |
|
|
* any time. If a buffer becomes dirty here after we've inspected it
|
| 615 |
|
|
* then we just miss that fact, and the page stays dirty.
|
| 616 |
|
|
*
|
| 617 |
|
|
* Buffers outside i_size may be dirtied by __set_page_dirty_buffers;
|
| 618 |
|
|
* handle that here by just cleaning them.
|
| 619 |
|
|
*/
|
| 620 |
|
|
|
| 621 |
|
|
/*
|
| 622 |
|
|
* Loop through all the buffers in the page, mapping all the dirty
|
| 623 |
|
|
* buffers to disk addresses and handling any aliases from the
|
| 624 |
|
|
* underlying block device's mapping.
|
| 625 |
|
|
*/
|
| 626 |
|
|
rl = NULL;
|
| 627 |
|
|
err = 0;
|
| 628 |
|
|
do {
|
| 629 |
|
|
bool is_retry = false;
|
| 630 |
|
|
|
| 631 |
|
|
if (unlikely(block >= dblock)) {
|
| 632 |
|
|
/*
|
| 633 |
|
|
* Mapped buffers outside i_size will occur, because
|
| 634 |
|
|
* this page can be outside i_size when there is a
|
| 635 |
|
|
* truncate in progress. The contents of such buffers
|
| 636 |
|
|
* were zeroed by ntfs_writepage().
|
| 637 |
|
|
*
|
| 638 |
|
|
* FIXME: What about the small race window where
|
| 639 |
|
|
* ntfs_writepage() has not done any clearing because
|
| 640 |
|
|
* the page was within i_size but before we get here,
|
| 641 |
|
|
* vmtruncate() modifies i_size?
|
| 642 |
|
|
*/
|
| 643 |
|
|
clear_buffer_dirty(bh);
|
| 644 |
|
|
set_buffer_uptodate(bh);
|
| 645 |
|
|
continue;
|
| 646 |
|
|
}
|
| 647 |
|
|
|
| 648 |
|
|
/* Clean buffers are not written out, so no need to map them. */
|
| 649 |
|
|
if (!buffer_dirty(bh))
|
| 650 |
|
|
continue;
|
| 651 |
|
|
|
| 652 |
|
|
/* Make sure we have enough initialized size. */
|
| 653 |
|
|
if (unlikely((block >= iblock) &&
|
| 654 |
|
|
(initialized_size < i_size))) {
|
| 655 |
|
|
/*
|
| 656 |
|
|
* If this page is fully outside initialized size, zero
|
| 657 |
|
|
* out all pages between the current initialized size
|
| 658 |
|
|
* and the current page. Just use ntfs_readpage() to do
|
| 659 |
|
|
* the zeroing transparently.
|
| 660 |
|
|
*/
|
| 661 |
|
|
if (block > iblock) {
|
| 662 |
|
|
// TODO:
|
| 663 |
|
|
// For each page do:
|
| 664 |
|
|
// - read_cache_page()
|
| 665 |
|
|
// Again for each page do:
|
| 666 |
|
|
// - wait_on_page_locked()
|
| 667 |
|
|
// - Check (PageUptodate(page) &&
|
| 668 |
|
|
// !PageError(page))
|
| 669 |
|
|
// Update initialized size in the attribute and
|
| 670 |
|
|
// in the inode.
|
| 671 |
|
|
// Again, for each page do:
|
| 672 |
|
|
// __set_page_dirty_buffers();
|
| 673 |
|
|
// page_cache_release()
|
| 674 |
|
|
// We don't need to wait on the writes.
|
| 675 |
|
|
// Update iblock.
|
| 676 |
|
|
}
|
| 677 |
|
|
/*
|
| 678 |
|
|
* The current page straddles initialized size. Zero
|
| 679 |
|
|
* all non-uptodate buffers and set them uptodate (and
|
| 680 |
|
|
* dirty?). Note, there aren't any non-uptodate buffers
|
| 681 |
|
|
* if the page is uptodate.
|
| 682 |
|
|
* FIXME: For an uptodate page, the buffers may need to
|
| 683 |
|
|
* be written out because they were not initialized on
|
| 684 |
|
|
* disk before.
|
| 685 |
|
|
*/
|
| 686 |
|
|
if (!PageUptodate(page)) {
|
| 687 |
|
|
// TODO:
|
| 688 |
|
|
// Zero any non-uptodate buffers up to i_size.
|
| 689 |
|
|
// Set them uptodate and dirty.
|
| 690 |
|
|
}
|
| 691 |
|
|
// TODO:
|
| 692 |
|
|
// Update initialized size in the attribute and in the
|
| 693 |
|
|
// inode (up to i_size).
|
| 694 |
|
|
// Update iblock.
|
| 695 |
|
|
// FIXME: This is inefficient. Try to batch the two
|
| 696 |
|
|
// size changes to happen in one go.
|
| 697 |
|
|
ntfs_error(vol->sb, "Writing beyond initialized size "
|
| 698 |
|
|
"is not supported yet. Sorry.");
|
| 699 |
|
|
err = -EOPNOTSUPP;
|
| 700 |
|
|
break;
|
| 701 |
|
|
// Do NOT set_buffer_new() BUT DO clear buffer range
|
| 702 |
|
|
// outside write request range.
|
| 703 |
|
|
// set_buffer_uptodate() on complete buffers as well as
|
| 704 |
|
|
// set_buffer_dirty().
|
| 705 |
|
|
}
|
| 706 |
|
|
|
| 707 |
|
|
/* No need to map buffers that are already mapped. */
|
| 708 |
|
|
if (buffer_mapped(bh))
|
| 709 |
|
|
continue;
|
| 710 |
|
|
|
| 711 |
|
|
/* Unmapped, dirty buffer. Need to map it. */
|
| 712 |
|
|
bh->b_bdev = vol->sb->s_bdev;
|
| 713 |
|
|
|
| 714 |
|
|
/* Convert block into corresponding vcn and offset. */
|
| 715 |
|
|
vcn = (VCN)block << blocksize_bits;
|
| 716 |
|
|
vcn_ofs = vcn & vol->cluster_size_mask;
|
| 717 |
|
|
vcn >>= vol->cluster_size_bits;
|
| 718 |
|
|
if (!rl) {
|
| 719 |
|
|
lock_retry_remap:
|
| 720 |
|
|
down_read(&ni->runlist.lock);
|
| 721 |
|
|
rl = ni->runlist.rl;
|
| 722 |
|
|
}
|
| 723 |
|
|
if (likely(rl != NULL)) {
|
| 724 |
|
|
/* Seek to element containing target vcn. */
|
| 725 |
|
|
while (rl->length && rl[1].vcn <= vcn)
|
| 726 |
|
|
rl++;
|
| 727 |
|
|
lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
|
| 728 |
|
|
} else
|
| 729 |
|
|
lcn = LCN_RL_NOT_MAPPED;
|
| 730 |
|
|
/* Successful remap. */
|
| 731 |
|
|
if (lcn >= 0) {
|
| 732 |
|
|
/* Setup buffer head to point to correct block. */
|
| 733 |
|
|
bh->b_blocknr = ((lcn << vol->cluster_size_bits) +
|
| 734 |
|
|
vcn_ofs) >> blocksize_bits;
|
| 735 |
|
|
set_buffer_mapped(bh);
|
| 736 |
|
|
continue;
|
| 737 |
|
|
}
|
| 738 |
|
|
/* It is a hole, need to instantiate it. */
|
| 739 |
|
|
if (lcn == LCN_HOLE) {
|
| 740 |
|
|
u8 *kaddr;
|
| 741 |
|
|
unsigned long *bpos, *bend;
|
| 742 |
|
|
|
| 743 |
|
|
/* Check if the buffer is zero. */
|
| 744 |
|
|
kaddr = kmap_atomic(page, KM_USER0);
|
| 745 |
|
|
bpos = (unsigned long *)(kaddr + bh_offset(bh));
|
| 746 |
|
|
bend = (unsigned long *)((u8*)bpos + blocksize);
|
| 747 |
|
|
do {
|
| 748 |
|
|
if (unlikely(*bpos))
|
| 749 |
|
|
break;
|
| 750 |
|
|
} while (likely(++bpos < bend));
|
| 751 |
|
|
kunmap_atomic(kaddr, KM_USER0);
|
| 752 |
|
|
if (bpos == bend) {
|
| 753 |
|
|
/*
|
| 754 |
|
|
* Buffer is zero and sparse, no need to write
|
| 755 |
|
|
* it.
|
| 756 |
|
|
*/
|
| 757 |
|
|
bh->b_blocknr = -1;
|
| 758 |
|
|
clear_buffer_dirty(bh);
|
| 759 |
|
|
continue;
|
| 760 |
|
|
}
|
| 761 |
|
|
// TODO: Instantiate the hole.
|
| 762 |
|
|
// clear_buffer_new(bh);
|
| 763 |
|
|
// unmap_underlying_metadata(bh->b_bdev, bh->b_blocknr);
|
| 764 |
|
|
ntfs_error(vol->sb, "Writing into sparse regions is "
|
| 765 |
|
|
"not supported yet. Sorry.");
|
| 766 |
|
|
err = -EOPNOTSUPP;
|
| 767 |
|
|
break;
|
| 768 |
|
|
}
|
| 769 |
|
|
/* If first try and runlist unmapped, map and retry. */
|
| 770 |
|
|
if (!is_retry && lcn == LCN_RL_NOT_MAPPED) {
|
| 771 |
|
|
is_retry = true;
|
| 772 |
|
|
/*
|
| 773 |
|
|
* Attempt to map runlist, dropping lock for
|
| 774 |
|
|
* the duration.
|
| 775 |
|
|
*/
|
| 776 |
|
|
up_read(&ni->runlist.lock);
|
| 777 |
|
|
err = ntfs_map_runlist(ni, vcn);
|
| 778 |
|
|
if (likely(!err))
|
| 779 |
|
|
goto lock_retry_remap;
|
| 780 |
|
|
rl = NULL;
|
| 781 |
|
|
} else if (!rl)
|
| 782 |
|
|
up_read(&ni->runlist.lock);
|
| 783 |
|
|
/*
|
| 784 |
|
|
* If buffer is outside the runlist, truncate has cut it out
|
| 785 |
|
|
* of the runlist. Just clean and clear the buffer and set it
|
| 786 |
|
|
* uptodate so it can get discarded by the VM.
|
| 787 |
|
|
*/
|
| 788 |
|
|
if (err == -ENOENT || lcn == LCN_ENOENT) {
|
| 789 |
|
|
bh->b_blocknr = -1;
|
| 790 |
|
|
clear_buffer_dirty(bh);
|
| 791 |
|
|
zero_user_page(page, bh_offset(bh), blocksize,
|
| 792 |
|
|
KM_USER0);
|
| 793 |
|
|
set_buffer_uptodate(bh);
|
| 794 |
|
|
err = 0;
|
| 795 |
|
|
continue;
|
| 796 |
|
|
}
|
| 797 |
|
|
/* Failed to map the buffer, even after retrying. */
|
| 798 |
|
|
if (!err)
|
| 799 |
|
|
err = -EIO;
|
| 800 |
|
|
bh->b_blocknr = -1;
|
| 801 |
|
|
ntfs_error(vol->sb, "Failed to write to inode 0x%lx, "
|
| 802 |
|
|
"attribute type 0x%x, vcn 0x%llx, offset 0x%x "
|
| 803 |
|
|
"because its location on disk could not be "
|
| 804 |
|
|
"determined%s (error code %i).", ni->mft_no,
|
| 805 |
|
|
ni->type, (unsigned long long)vcn,
|
| 806 |
|
|
vcn_ofs, is_retry ? " even after "
|
| 807 |
|
|
"retrying" : "", err);
|
| 808 |
|
|
break;
|
| 809 |
|
|
} while (block++, (bh = bh->b_this_page) != head);
|
| 810 |
|
|
|
| 811 |
|
|
/* Release the lock if we took it. */
|
| 812 |
|
|
if (rl)
|
| 813 |
|
|
up_read(&ni->runlist.lock);
|
| 814 |
|
|
|
| 815 |
|
|
/* For the error case, need to reset bh to the beginning. */
|
| 816 |
|
|
bh = head;
|
| 817 |
|
|
|
| 818 |
|
|
/* Just an optimization, so ->readpage() is not called later. */
|
| 819 |
|
|
if (unlikely(!PageUptodate(page))) {
|
| 820 |
|
|
int uptodate = 1;
|
| 821 |
|
|
do {
|
| 822 |
|
|
if (!buffer_uptodate(bh)) {
|
| 823 |
|
|
uptodate = 0;
|
| 824 |
|
|
bh = head;
|
| 825 |
|
|
break;
|
| 826 |
|
|
}
|
| 827 |
|
|
} while ((bh = bh->b_this_page) != head);
|
| 828 |
|
|
if (uptodate)
|
| 829 |
|
|
SetPageUptodate(page);
|
| 830 |
|
|
}
|
| 831 |
|
|
|
| 832 |
|
|
/* Setup all mapped, dirty buffers for async write i/o. */
|
| 833 |
|
|
do {
|
| 834 |
|
|
if (buffer_mapped(bh) && buffer_dirty(bh)) {
|
| 835 |
|
|
lock_buffer(bh);
|
| 836 |
|
|
if (test_clear_buffer_dirty(bh)) {
|
| 837 |
|
|
BUG_ON(!buffer_uptodate(bh));
|
| 838 |
|
|
mark_buffer_async_write(bh);
|
| 839 |
|
|
} else
|
| 840 |
|
|
unlock_buffer(bh);
|
| 841 |
|
|
} else if (unlikely(err)) {
|
| 842 |
|
|
/*
|
| 843 |
|
|
* For the error case. The buffer may have been set
|
| 844 |
|
|
* dirty during attachment to a dirty page.
|
| 845 |
|
|
*/
|
| 846 |
|
|
if (err != -ENOMEM)
|
| 847 |
|
|
clear_buffer_dirty(bh);
|
| 848 |
|
|
}
|
| 849 |
|
|
} while ((bh = bh->b_this_page) != head);
|
| 850 |
|
|
|
| 851 |
|
|
if (unlikely(err)) {
|
| 852 |
|
|
// TODO: Remove the -EOPNOTSUPP check later on...
|
| 853 |
|
|
if (unlikely(err == -EOPNOTSUPP))
|
| 854 |
|
|
err = 0;
|
| 855 |
|
|
else if (err == -ENOMEM) {
|
| 856 |
|
|
ntfs_warning(vol->sb, "Error allocating memory. "
|
| 857 |
|
|
"Redirtying page so we try again "
|
| 858 |
|
|
"later.");
|
| 859 |
|
|
/*
|
| 860 |
|
|
* Put the page back on mapping->dirty_pages, but
|
| 861 |
|
|
* leave its buffer's dirty state as-is.
|
| 862 |
|
|
*/
|
| 863 |
|
|
redirty_page_for_writepage(wbc, page);
|
| 864 |
|
|
err = 0;
|
| 865 |
|
|
} else
|
| 866 |
|
|
SetPageError(page);
|
| 867 |
|
|
}
|
| 868 |
|
|
|
| 869 |
|
|
BUG_ON(PageWriteback(page));
|
| 870 |
|
|
set_page_writeback(page); /* Keeps try_to_free_buffers() away. */
|
| 871 |
|
|
|
| 872 |
|
|
/* Submit the prepared buffers for i/o. */
|
| 873 |
|
|
need_end_writeback = true;
|
| 874 |
|
|
do {
|
| 875 |
|
|
struct buffer_head *next = bh->b_this_page;
|
| 876 |
|
|
if (buffer_async_write(bh)) {
|
| 877 |
|
|
submit_bh(WRITE, bh);
|
| 878 |
|
|
need_end_writeback = false;
|
| 879 |
|
|
}
|
| 880 |
|
|
bh = next;
|
| 881 |
|
|
} while (bh != head);
|
| 882 |
|
|
unlock_page(page);
|
| 883 |
|
|
|
| 884 |
|
|
/* If no i/o was started, need to end_page_writeback(). */
|
| 885 |
|
|
if (unlikely(need_end_writeback))
|
| 886 |
|
|
end_page_writeback(page);
|
| 887 |
|
|
|
| 888 |
|
|
ntfs_debug("Done.");
|
| 889 |
|
|
return err;
|
| 890 |
|
|
}
|
| 891 |
|
|
|
| 892 |
|
|
/**
|
| 893 |
|
|
* ntfs_write_mst_block - write a @page to the backing store
|
| 894 |
|
|
* @page: page cache page to write out
|
| 895 |
|
|
* @wbc: writeback control structure
|
| 896 |
|
|
*
|
| 897 |
|
|
* This function is for writing pages belonging to non-resident, mst protected
|
| 898 |
|
|
* attributes to their backing store. The only supported attributes are index
|
| 899 |
|
|
* allocation and $MFT/$DATA. Both directory inodes and index inodes are
|
| 900 |
|
|
* supported for the index allocation case.
|
| 901 |
|
|
*
|
| 902 |
|
|
* The page must remain locked for the duration of the write because we apply
|
| 903 |
|
|
* the mst fixups, write, and then undo the fixups, so if we were to unlock the
|
| 904 |
|
|
* page before undoing the fixups, any other user of the page will see the
|
| 905 |
|
|
* page contents as corrupt.
|
| 906 |
|
|
*
|
| 907 |
|
|
* We clear the page uptodate flag for the duration of the function to ensure
|
| 908 |
|
|
* exclusion for the $MFT/$DATA case against someone mapping an mft record we
|
| 909 |
|
|
* are about to apply the mst fixups to.
|
| 910 |
|
|
*
|
| 911 |
|
|
* Return 0 on success and -errno on error.
|
| 912 |
|
|
*
|
| 913 |
|
|
* Based on ntfs_write_block(), ntfs_mft_writepage(), and
|
| 914 |
|
|
* write_mft_record_nolock().
|
| 915 |
|
|
*/
|
| 916 |
|
|
static int ntfs_write_mst_block(struct page *page,
|
| 917 |
|
|
struct writeback_control *wbc)
|
| 918 |
|
|
{
|
| 919 |
|
|
sector_t block, dblock, rec_block;
|
| 920 |
|
|
struct inode *vi = page->mapping->host;
|
| 921 |
|
|
ntfs_inode *ni = NTFS_I(vi);
|
| 922 |
|
|
ntfs_volume *vol = ni->vol;
|
| 923 |
|
|
u8 *kaddr;
|
| 924 |
|
|
unsigned int rec_size = ni->itype.index.block_size;
|
| 925 |
|
|
ntfs_inode *locked_nis[PAGE_CACHE_SIZE / rec_size];
|
| 926 |
|
|
struct buffer_head *bh, *head, *tbh, *rec_start_bh;
|
| 927 |
|
|
struct buffer_head *bhs[MAX_BUF_PER_PAGE];
|
| 928 |
|
|
runlist_element *rl;
|
| 929 |
|
|
int i, nr_locked_nis, nr_recs, nr_bhs, max_bhs, bhs_per_rec, err, err2;
|
| 930 |
|
|
unsigned bh_size, rec_size_bits;
|
| 931 |
|
|
bool sync, is_mft, page_is_dirty, rec_is_dirty;
|
| 932 |
|
|
unsigned char bh_size_bits;
|
| 933 |
|
|
|
| 934 |
|
|
ntfs_debug("Entering for inode 0x%lx, attribute type 0x%x, page index "
|
| 935 |
|
|
"0x%lx.", vi->i_ino, ni->type, page->index);
|
| 936 |
|
|
BUG_ON(!NInoNonResident(ni));
|
| 937 |
|
|
BUG_ON(!NInoMstProtected(ni));
|
| 938 |
|
|
is_mft = (S_ISREG(vi->i_mode) && !vi->i_ino);
|
| 939 |
|
|
/*
|
| 940 |
|
|
* NOTE: ntfs_write_mst_block() would be called for $MFTMirr if a page
|
| 941 |
|
|
* in its page cache were to be marked dirty. However this should
|
| 942 |
|
|
* never happen with the current driver and considering we do not
|
| 943 |
|
|
* handle this case here we do want to BUG(), at least for now.
|
| 944 |
|
|
*/
|
| 945 |
|
|
BUG_ON(!(is_mft || S_ISDIR(vi->i_mode) ||
|
| 946 |
|
|
(NInoAttr(ni) && ni->type == AT_INDEX_ALLOCATION)));
|
| 947 |
|
|
bh_size = vol->sb->s_blocksize;
|
| 948 |
|
|
bh_size_bits = vol->sb->s_blocksize_bits;
|
| 949 |
|
|
max_bhs = PAGE_CACHE_SIZE / bh_size;
|
| 950 |
|
|
BUG_ON(!max_bhs);
|
| 951 |
|
|
BUG_ON(max_bhs > MAX_BUF_PER_PAGE);
|
| 952 |
|
|
|
| 953 |
|
|
/* Were we called for sync purposes? */
|
| 954 |
|
|
sync = (wbc->sync_mode == WB_SYNC_ALL);
|
| 955 |
|
|
|
| 956 |
|
|
/* Make sure we have mapped buffers. */
|
| 957 |
|
|
bh = head = page_buffers(page);
|
| 958 |
|
|
BUG_ON(!bh);
|
| 959 |
|
|
|
| 960 |
|
|
rec_size_bits = ni->itype.index.block_size_bits;
|
| 961 |
|
|
BUG_ON(!(PAGE_CACHE_SIZE >> rec_size_bits));
|
| 962 |
|
|
bhs_per_rec = rec_size >> bh_size_bits;
|
| 963 |
|
|
BUG_ON(!bhs_per_rec);
|
| 964 |
|
|
|
| 965 |
|
|
/* The first block in the page. */
|
| 966 |
|
|
rec_block = block = (sector_t)page->index <<
|
| 967 |
|
|
(PAGE_CACHE_SHIFT - bh_size_bits);
|
| 968 |
|
|
|
| 969 |
|
|
/* The first out of bounds block for the data size. */
|
| 970 |
|
|
dblock = (i_size_read(vi) + bh_size - 1) >> bh_size_bits;
|
| 971 |
|
|
|
| 972 |
|
|
rl = NULL;
|
| 973 |
|
|
err = err2 = nr_bhs = nr_recs = nr_locked_nis = 0;
|
| 974 |
|
|
page_is_dirty = rec_is_dirty = false;
|
| 975 |
|
|
rec_start_bh = NULL;
|
| 976 |
|
|
do {
|
| 977 |
|
|
bool is_retry = false;
|
| 978 |
|
|
|
| 979 |
|
|
if (likely(block < rec_block)) {
|
| 980 |
|
|
if (unlikely(block >= dblock)) {
|
| 981 |
|
|
clear_buffer_dirty(bh);
|
| 982 |
|
|
set_buffer_uptodate(bh);
|
| 983 |
|
|
continue;
|
| 984 |
|
|
}
|
| 985 |
|
|
/*
|
| 986 |
|
|
* This block is not the first one in the record. We
|
| 987 |
|
|
* ignore the buffer's dirty state because we could
|
| 988 |
|
|
* have raced with a parallel mark_ntfs_record_dirty().
|
| 989 |
|
|
*/
|
| 990 |
|
|
if (!rec_is_dirty)
|
| 991 |
|
|
continue;
|
| 992 |
|
|
if (unlikely(err2)) {
|
| 993 |
|
|
if (err2 != -ENOMEM)
|
| 994 |
|
|
clear_buffer_dirty(bh);
|
| 995 |
|
|
continue;
|
| 996 |
|
|
}
|
| 997 |
|
|
} else /* if (block == rec_block) */ {
|
| 998 |
|
|
BUG_ON(block > rec_block);
|
| 999 |
|
|
/* This block is the first one in the record. */
|
| 1000 |
|
|
rec_block += bhs_per_rec;
|
| 1001 |
|
|
err2 = 0;
|
| 1002 |
|
|
if (unlikely(block >= dblock)) {
|
| 1003 |
|
|
clear_buffer_dirty(bh);
|
| 1004 |
|
|
continue;
|
| 1005 |
|
|
}
|
| 1006 |
|
|
if (!buffer_dirty(bh)) {
|
| 1007 |
|
|
/* Clean records are not written out. */
|
| 1008 |
|
|
rec_is_dirty = false;
|
| 1009 |
|
|
continue;
|
| 1010 |
|
|
}
|
| 1011 |
|
|
rec_is_dirty = true;
|
| 1012 |
|
|
rec_start_bh = bh;
|
| 1013 |
|
|
}
|
| 1014 |
|
|
/* Need to map the buffer if it is not mapped already. */
|
| 1015 |
|
|
if (unlikely(!buffer_mapped(bh))) {
|
| 1016 |
|
|
VCN vcn;
|
| 1017 |
|
|
LCN lcn;
|
| 1018 |
|
|
unsigned int vcn_ofs;
|
| 1019 |
|
|
|
| 1020 |
|
|
bh->b_bdev = vol->sb->s_bdev;
|
| 1021 |
|
|
/* Obtain the vcn and offset of the current block. */
|
| 1022 |
|
|
vcn = (VCN)block << bh_size_bits;
|
| 1023 |
|
|
vcn_ofs = vcn & vol->cluster_size_mask;
|
| 1024 |
|
|
vcn >>= vol->cluster_size_bits;
|
| 1025 |
|
|
if (!rl) {
|
| 1026 |
|
|
lock_retry_remap:
|
| 1027 |
|
|
down_read(&ni->runlist.lock);
|
| 1028 |
|
|
rl = ni->runlist.rl;
|
| 1029 |
|
|
}
|
| 1030 |
|
|
if (likely(rl != NULL)) {
|
| 1031 |
|
|
/* Seek to element containing target vcn. */
|
| 1032 |
|
|
while (rl->length && rl[1].vcn <= vcn)
|
| 1033 |
|
|
rl++;
|
| 1034 |
|
|
lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
|
| 1035 |
|
|
} else
|
| 1036 |
|
|
lcn = LCN_RL_NOT_MAPPED;
|
| 1037 |
|
|
/* Successful remap. */
|
| 1038 |
|
|
if (likely(lcn >= 0)) {
|
| 1039 |
|
|
/* Setup buffer head to correct block. */
|
| 1040 |
|
|
bh->b_blocknr = ((lcn <<
|
| 1041 |
|
|
vol->cluster_size_bits) +
|
| 1042 |
|
|
vcn_ofs) >> bh_size_bits;
|
| 1043 |
|
|
set_buffer_mapped(bh);
|
| 1044 |
|
|
} else {
|
| 1045 |
|
|
/*
|
| 1046 |
|
|
* Remap failed. Retry to map the runlist once
|
| 1047 |
|
|
* unless we are working on $MFT which always
|
| 1048 |
|
|
* has the whole of its runlist in memory.
|
| 1049 |
|
|
*/
|
| 1050 |
|
|
if (!is_mft && !is_retry &&
|
| 1051 |
|
|
lcn == LCN_RL_NOT_MAPPED) {
|
| 1052 |
|
|
is_retry = true;
|
| 1053 |
|
|
/*
|
| 1054 |
|
|
* Attempt to map runlist, dropping
|
| 1055 |
|
|
* lock for the duration.
|
| 1056 |
|
|
*/
|
| 1057 |
|
|
up_read(&ni->runlist.lock);
|
| 1058 |
|
|
err2 = ntfs_map_runlist(ni, vcn);
|
| 1059 |
|
|
if (likely(!err2))
|
| 1060 |
|
|
goto lock_retry_remap;
|
| 1061 |
|
|
if (err2 == -ENOMEM)
|
| 1062 |
|
|
page_is_dirty = true;
|
| 1063 |
|
|
lcn = err2;
|
| 1064 |
|
|
} else {
|
| 1065 |
|
|
err2 = -EIO;
|
| 1066 |
|
|
if (!rl)
|
| 1067 |
|
|
up_read(&ni->runlist.lock);
|
| 1068 |
|
|
}
|
| 1069 |
|
|
/* Hard error. Abort writing this record. */
|
| 1070 |
|
|
if (!err || err == -ENOMEM)
|
| 1071 |
|
|
err = err2;
|
| 1072 |
|
|
bh->b_blocknr = -1;
|
| 1073 |
|
|
ntfs_error(vol->sb, "Cannot write ntfs record "
|
| 1074 |
|
|
"0x%llx (inode 0x%lx, "
|
| 1075 |
|
|
"attribute type 0x%x) because "
|
| 1076 |
|
|
"its location on disk could "
|
| 1077 |
|
|
"not be determined (error "
|
| 1078 |
|
|
"code %lli).",
|
| 1079 |
|
|
(long long)block <<
|
| 1080 |
|
|
bh_size_bits >>
|
| 1081 |
|
|
vol->mft_record_size_bits,
|
| 1082 |
|
|
ni->mft_no, ni->type,
|
| 1083 |
|
|
(long long)lcn);
|
| 1084 |
|
|
/*
|
| 1085 |
|
|
* If this is not the first buffer, remove the
|
| 1086 |
|
|
* buffers in this record from the list of
|
| 1087 |
|
|
* buffers to write and clear their dirty bit
|
| 1088 |
|
|
* if not error -ENOMEM.
|
| 1089 |
|
|
*/
|
| 1090 |
|
|
if (rec_start_bh != bh) {
|
| 1091 |
|
|
while (bhs[--nr_bhs] != rec_start_bh)
|
| 1092 |
|
|
;
|
| 1093 |
|
|
if (err2 != -ENOMEM) {
|
| 1094 |
|
|
do {
|
| 1095 |
|
|
clear_buffer_dirty(
|
| 1096 |
|
|
rec_start_bh);
|
| 1097 |
|
|
} while ((rec_start_bh =
|
| 1098 |
|
|
rec_start_bh->
|
| 1099 |
|
|
b_this_page) !=
|
| 1100 |
|
|
bh);
|
| 1101 |
|
|
}
|
| 1102 |
|
|
}
|
| 1103 |
|
|
continue;
|
| 1104 |
|
|
}
|
| 1105 |
|
|
}
|
| 1106 |
|
|
BUG_ON(!buffer_uptodate(bh));
|
| 1107 |
|
|
BUG_ON(nr_bhs >= max_bhs);
|
| 1108 |
|
|
bhs[nr_bhs++] = bh;
|
| 1109 |
|
|
} while (block++, (bh = bh->b_this_page) != head);
|
| 1110 |
|
|
if (unlikely(rl))
|
| 1111 |
|
|
up_read(&ni->runlist.lock);
|
| 1112 |
|
|
/* If there were no dirty buffers, we are done. */
|
| 1113 |
|
|
if (!nr_bhs)
|
| 1114 |
|
|
goto done;
|
| 1115 |
|
|
/* Map the page so we can access its contents. */
|
| 1116 |
|
|
kaddr = kmap(page);
|
| 1117 |
|
|
/* Clear the page uptodate flag whilst the mst fixups are applied. */
|
| 1118 |
|
|
BUG_ON(!PageUptodate(page));
|
| 1119 |
|
|
ClearPageUptodate(page);
|
| 1120 |
|
|
for (i = 0; i < nr_bhs; i++) {
|
| 1121 |
|
|
unsigned int ofs;
|
| 1122 |
|
|
|
| 1123 |
|
|
/* Skip buffers which are not at the beginning of records. */
|
| 1124 |
|
|
if (i % bhs_per_rec)
|
| 1125 |
|
|
continue;
|
| 1126 |
|
|
tbh = bhs[i];
|
| 1127 |
|
|
ofs = bh_offset(tbh);
|
| 1128 |
|
|
if (is_mft) {
|
| 1129 |
|
|
ntfs_inode *tni;
|
| 1130 |
|
|
unsigned long mft_no;
|
| 1131 |
|
|
|
| 1132 |
|
|
/* Get the mft record number. */
|
| 1133 |
|
|
mft_no = (((s64)page->index << PAGE_CACHE_SHIFT) + ofs)
|
| 1134 |
|
|
>> rec_size_bits;
|
| 1135 |
|
|
/* Check whether to write this mft record. */
|
| 1136 |
|
|
tni = NULL;
|
| 1137 |
|
|
if (!ntfs_may_write_mft_record(vol, mft_no,
|
| 1138 |
|
|
(MFT_RECORD*)(kaddr + ofs), &tni)) {
|
| 1139 |
|
|
/*
|
| 1140 |
|
|
* The record should not be written. This
|
| 1141 |
|
|
* means we need to redirty the page before
|
| 1142 |
|
|
* returning.
|
| 1143 |
|
|
*/
|
| 1144 |
|
|
page_is_dirty = true;
|
| 1145 |
|
|
/*
|
| 1146 |
|
|
* Remove the buffers in this mft record from
|
| 1147 |
|
|
* the list of buffers to write.
|
| 1148 |
|
|
*/
|
| 1149 |
|
|
do {
|
| 1150 |
|
|
bhs[i] = NULL;
|
| 1151 |
|
|
} while (++i % bhs_per_rec);
|
| 1152 |
|
|
continue;
|
| 1153 |
|
|
}
|
| 1154 |
|
|
/*
|
| 1155 |
|
|
* The record should be written. If a locked ntfs
|
| 1156 |
|
|
* inode was returned, add it to the array of locked
|
| 1157 |
|
|
* ntfs inodes.
|
| 1158 |
|
|
*/
|
| 1159 |
|
|
if (tni)
|
| 1160 |
|
|
locked_nis[nr_locked_nis++] = tni;
|
| 1161 |
|
|
}
|
| 1162 |
|
|
/* Apply the mst protection fixups. */
|
| 1163 |
|
|
err2 = pre_write_mst_fixup((NTFS_RECORD*)(kaddr + ofs),
|
| 1164 |
|
|
rec_size);
|
| 1165 |
|
|
if (unlikely(err2)) {
|
| 1166 |
|
|
if (!err || err == -ENOMEM)
|
| 1167 |
|
|
err = -EIO;
|
| 1168 |
|
|
ntfs_error(vol->sb, "Failed to apply mst fixups "
|
| 1169 |
|
|
"(inode 0x%lx, attribute type 0x%x, "
|
| 1170 |
|
|
"page index 0x%lx, page offset 0x%x)!"
|
| 1171 |
|
|
" Unmount and run chkdsk.", vi->i_ino,
|
| 1172 |
|
|
ni->type, page->index, ofs);
|
| 1173 |
|
|
/*
|
| 1174 |
|
|
* Mark all the buffers in this record clean as we do
|
| 1175 |
|
|
* not want to write corrupt data to disk.
|
| 1176 |
|
|
*/
|
| 1177 |
|
|
do {
|
| 1178 |
|
|
clear_buffer_dirty(bhs[i]);
|
| 1179 |
|
|
bhs[i] = NULL;
|
| 1180 |
|
|
} while (++i % bhs_per_rec);
|
| 1181 |
|
|
continue;
|
| 1182 |
|
|
}
|
| 1183 |
|
|
nr_recs++;
|
| 1184 |
|
|
}
|
| 1185 |
|
|
/* If no records are to be written out, we are done. */
|
| 1186 |
|
|
if (!nr_recs)
|
| 1187 |
|
|
goto unm_done;
|
| 1188 |
|
|
flush_dcache_page(page);
|
| 1189 |
|
|
/* Lock buffers and start synchronous write i/o on them. */
|
| 1190 |
|
|
for (i = 0; i < nr_bhs; i++) {
|
| 1191 |
|
|
tbh = bhs[i];
|
| 1192 |
|
|
if (!tbh)
|
| 1193 |
|
|
continue;
|
| 1194 |
|
|
if (unlikely(test_set_buffer_locked(tbh)))
|
| 1195 |
|
|
BUG();
|
| 1196 |
|
|
/* The buffer dirty state is now irrelevant, just clean it. */
|
| 1197 |
|
|
clear_buffer_dirty(tbh);
|
| 1198 |
|
|
BUG_ON(!buffer_uptodate(tbh));
|
| 1199 |
|
|
BUG_ON(!buffer_mapped(tbh));
|
| 1200 |
|
|
get_bh(tbh);
|
| 1201 |
|
|
tbh->b_end_io = end_buffer_write_sync;
|
| 1202 |
|
|
submit_bh(WRITE, tbh);
|
| 1203 |
|
|
}
|
| 1204 |
|
|
/* Synchronize the mft mirror now if not @sync. */
|
| 1205 |
|
|
if (is_mft && !sync)
|
| 1206 |
|
|
goto do_mirror;
|
| 1207 |
|
|
do_wait:
|
| 1208 |
|
|
/* Wait on i/o completion of buffers. */
|
| 1209 |
|
|
for (i = 0; i < nr_bhs; i++) {
|
| 1210 |
|
|
tbh = bhs[i];
|
| 1211 |
|
|
if (!tbh)
|
| 1212 |
|
|
continue;
|
| 1213 |
|
|
wait_on_buffer(tbh);
|
| 1214 |
|
|
if (unlikely(!buffer_uptodate(tbh))) {
|
| 1215 |
|
|
ntfs_error(vol->sb, "I/O error while writing ntfs "
|
| 1216 |
|
|
"record buffer (inode 0x%lx, "
|
| 1217 |
|
|
"attribute type 0x%x, page index "
|
| 1218 |
|
|
"0x%lx, page offset 0x%lx)! Unmount "
|
| 1219 |
|
|
"and run chkdsk.", vi->i_ino, ni->type,
|
| 1220 |
|
|
page->index, bh_offset(tbh));
|
| 1221 |
|
|
if (!err || err == -ENOMEM)
|
| 1222 |
|
|
err = -EIO;
|
| 1223 |
|
|
/*
|
| 1224 |
|
|
* Set the buffer uptodate so the page and buffer
|
| 1225 |
|
|
* states do not become out of sync.
|
| 1226 |
|
|
*/
|
| 1227 |
|
|
set_buffer_uptodate(tbh);
|
| 1228 |
|
|
}
|
| 1229 |
|
|
}
|
| 1230 |
|
|
/* If @sync, now synchronize the mft mirror. */
|
| 1231 |
|
|
if (is_mft && sync) {
|
| 1232 |
|
|
do_mirror:
|
| 1233 |
|
|
for (i = 0; i < nr_bhs; i++) {
|
| 1234 |
|
|
unsigned long mft_no;
|
| 1235 |
|
|
unsigned int ofs;
|
| 1236 |
|
|
|
| 1237 |
|
|
/*
|
| 1238 |
|
|
* Skip buffers which are not at the beginning of
|
| 1239 |
|
|
* records.
|
| 1240 |
|
|
*/
|
| 1241 |
|
|
if (i % bhs_per_rec)
|
| 1242 |
|
|
continue;
|
| 1243 |
|
|
tbh = bhs[i];
|
| 1244 |
|
|
/* Skip removed buffers (and hence records). */
|
| 1245 |
|
|
if (!tbh)
|
| 1246 |
|
|
continue;
|
| 1247 |
|
|
ofs = bh_offset(tbh);
|
| 1248 |
|
|
/* Get the mft record number. */
|
| 1249 |
|
|
mft_no = (((s64)page->index << PAGE_CACHE_SHIFT) + ofs)
|
| 1250 |
|
|
>> rec_size_bits;
|
| 1251 |
|
|
if (mft_no < vol->mftmirr_size)
|
| 1252 |
|
|
ntfs_sync_mft_mirror(vol, mft_no,
|
| 1253 |
|
|
(MFT_RECORD*)(kaddr + ofs),
|
| 1254 |
|
|
sync);
|
| 1255 |
|
|
}
|
| 1256 |
|
|
if (!sync)
|
| 1257 |
|
|
goto do_wait;
|
| 1258 |
|
|
}
|
| 1259 |
|
|
/* Remove the mst protection fixups again. */
|
| 1260 |
|
|
for (i = 0; i < nr_bhs; i++) {
|
| 1261 |
|
|
if (!(i % bhs_per_rec)) {
|
| 1262 |
|
|
tbh = bhs[i];
|
| 1263 |
|
|
if (!tbh)
|
| 1264 |
|
|
continue;
|
| 1265 |
|
|
post_write_mst_fixup((NTFS_RECORD*)(kaddr +
|
| 1266 |
|
|
bh_offset(tbh)));
|
| 1267 |
|
|
}
|
| 1268 |
|
|
}
|
| 1269 |
|
|
flush_dcache_page(page);
|
| 1270 |
|
|
unm_done:
|
| 1271 |
|
|
/* Unlock any locked inodes. */
|
| 1272 |
|
|
while (nr_locked_nis-- > 0) {
|
| 1273 |
|
|
ntfs_inode *tni, *base_tni;
|
| 1274 |
|
|
|
| 1275 |
|
|
tni = locked_nis[nr_locked_nis];
|
| 1276 |
|
|
/* Get the base inode. */
|
| 1277 |
|
|
mutex_lock(&tni->extent_lock);
|
| 1278 |
|
|
if (tni->nr_extents >= 0)
|
| 1279 |
|
|
base_tni = tni;
|
| 1280 |
|
|
else {
|
| 1281 |
|
|
base_tni = tni->ext.base_ntfs_ino;
|
| 1282 |
|
|
BUG_ON(!base_tni);
|
| 1283 |
|
|
}
|
| 1284 |
|
|
mutex_unlock(&tni->extent_lock);
|
| 1285 |
|
|
ntfs_debug("Unlocking %s inode 0x%lx.",
|
| 1286 |
|
|
tni == base_tni ? "base" : "extent",
|
| 1287 |
|
|
tni->mft_no);
|
| 1288 |
|
|
mutex_unlock(&tni->mrec_lock);
|
| 1289 |
|
|
atomic_dec(&tni->count);
|
| 1290 |
|
|
iput(VFS_I(base_tni));
|
| 1291 |
|
|
}
|
| 1292 |
|
|
SetPageUptodate(page);
|
| 1293 |
|
|
kunmap(page);
|
| 1294 |
|
|
done:
|
| 1295 |
|
|
if (unlikely(err && err != -ENOMEM)) {
|
| 1296 |
|
|
/*
|
| 1297 |
|
|
* Set page error if there is only one ntfs record in the page.
|
| 1298 |
|
|
* Otherwise we would loose per-record granularity.
|
| 1299 |
|
|
*/
|
| 1300 |
|
|
if (ni->itype.index.block_size == PAGE_CACHE_SIZE)
|
| 1301 |
|
|
SetPageError(page);
|
| 1302 |
|
|
NVolSetErrors(vol);
|
| 1303 |
|
|
}
|
| 1304 |
|
|
if (page_is_dirty) {
|
| 1305 |
|
|
ntfs_debug("Page still contains one or more dirty ntfs "
|
| 1306 |
|
|
"records. Redirtying the page starting at "
|
| 1307 |
|
|
"record 0x%lx.", page->index <<
|
| 1308 |
|
|
(PAGE_CACHE_SHIFT - rec_size_bits));
|
| 1309 |
|
|
redirty_page_for_writepage(wbc, page);
|
| 1310 |
|
|
unlock_page(page);
|
| 1311 |
|
|
} else {
|
| 1312 |
|
|
/*
|
| 1313 |
|
|
* Keep the VM happy. This must be done otherwise the
|
| 1314 |
|
|
* radix-tree tag PAGECACHE_TAG_DIRTY remains set even though
|
| 1315 |
|
|
* the page is clean.
|
| 1316 |
|
|
*/
|
| 1317 |
|
|
BUG_ON(PageWriteback(page));
|
| 1318 |
|
|
set_page_writeback(page);
|
| 1319 |
|
|
unlock_page(page);
|
| 1320 |
|
|
end_page_writeback(page);
|
| 1321 |
|
|
}
|
| 1322 |
|
|
if (likely(!err))
|
| 1323 |
|
|
ntfs_debug("Done.");
|
| 1324 |
|
|
return err;
|
| 1325 |
|
|
}
|
| 1326 |
|
|
|
| 1327 |
|
|
/**
|
| 1328 |
|
|
* ntfs_writepage - write a @page to the backing store
|
| 1329 |
|
|
* @page: page cache page to write out
|
| 1330 |
|
|
* @wbc: writeback control structure
|
| 1331 |
|
|
*
|
| 1332 |
|
|
* This is called from the VM when it wants to have a dirty ntfs page cache
|
| 1333 |
|
|
* page cleaned. The VM has already locked the page and marked it clean.
|
| 1334 |
|
|
*
|
| 1335 |
|
|
* For non-resident attributes, ntfs_writepage() writes the @page by calling
|
| 1336 |
|
|
* the ntfs version of the generic block_write_full_page() function,
|
| 1337 |
|
|
* ntfs_write_block(), which in turn if necessary creates and writes the
|
| 1338 |
|
|
* buffers associated with the page asynchronously.
|
| 1339 |
|
|
*
|
| 1340 |
|
|
* For resident attributes, OTOH, ntfs_writepage() writes the @page by copying
|
| 1341 |
|
|
* the data to the mft record (which at this stage is most likely in memory).
|
| 1342 |
|
|
* The mft record is then marked dirty and written out asynchronously via the
|
| 1343 |
|
|
* vfs inode dirty code path for the inode the mft record belongs to or via the
|
| 1344 |
|
|
* vm page dirty code path for the page the mft record is in.
|
| 1345 |
|
|
*
|
| 1346 |
|
|
* Based on ntfs_readpage() and fs/buffer.c::block_write_full_page().
|
| 1347 |
|
|
*
|
| 1348 |
|
|
* Return 0 on success and -errno on error.
|
| 1349 |
|
|
*/
|
| 1350 |
|
|
static int ntfs_writepage(struct page *page, struct writeback_control *wbc)
|
| 1351 |
|
|
{
|
| 1352 |
|
|
loff_t i_size;
|
| 1353 |
|
|
struct inode *vi = page->mapping->host;
|
| 1354 |
|
|
ntfs_inode *base_ni = NULL, *ni = NTFS_I(vi);
|
| 1355 |
|
|
char *addr;
|
| 1356 |
|
|
ntfs_attr_search_ctx *ctx = NULL;
|
| 1357 |
|
|
MFT_RECORD *m = NULL;
|
| 1358 |
|
|
u32 attr_len;
|
| 1359 |
|
|
int err;
|
| 1360 |
|
|
|
| 1361 |
|
|
retry_writepage:
|
| 1362 |
|
|
BUG_ON(!PageLocked(page));
|
| 1363 |
|
|
i_size = i_size_read(vi);
|
| 1364 |
|
|
/* Is the page fully outside i_size? (truncate in progress) */
|
| 1365 |
|
|
if (unlikely(page->index >= (i_size + PAGE_CACHE_SIZE - 1) >>
|
| 1366 |
|
|
PAGE_CACHE_SHIFT)) {
|
| 1367 |
|
|
/*
|
| 1368 |
|
|
* The page may have dirty, unmapped buffers. Make them
|
| 1369 |
|
|
* freeable here, so the page does not leak.
|
| 1370 |
|
|
*/
|
| 1371 |
|
|
block_invalidatepage(page, 0);
|
| 1372 |
|
|
unlock_page(page);
|
| 1373 |
|
|
ntfs_debug("Write outside i_size - truncated?");
|
| 1374 |
|
|
return 0;
|
| 1375 |
|
|
}
|
| 1376 |
|
|
/*
|
| 1377 |
|
|
* Only $DATA attributes can be encrypted and only unnamed $DATA
|
| 1378 |
|
|
* attributes can be compressed. Index root can have the flags set but
|
| 1379 |
|
|
* this means to create compressed/encrypted files, not that the
|
| 1380 |
|
|
* attribute is compressed/encrypted. Note we need to check for
|
| 1381 |
|
|
* AT_INDEX_ALLOCATION since this is the type of both directory and
|
| 1382 |
|
|
* index inodes.
|
| 1383 |
|
|
*/
|
| 1384 |
|
|
if (ni->type != AT_INDEX_ALLOCATION) {
|
| 1385 |
|
|
/* If file is encrypted, deny access, just like NT4. */
|
| 1386 |
|
|
if (NInoEncrypted(ni)) {
|
| 1387 |
|
|
unlock_page(page);
|
| 1388 |
|
|
BUG_ON(ni->type != AT_DATA);
|
| 1389 |
|
|
ntfs_debug("Denying write access to encrypted file.");
|
| 1390 |
|
|
return -EACCES;
|
| 1391 |
|
|
}
|
| 1392 |
|
|
/* Compressed data streams are handled in compress.c. */
|
| 1393 |
|
|
if (NInoNonResident(ni) && NInoCompressed(ni)) {
|
| 1394 |
|
|
BUG_ON(ni->type != AT_DATA);
|
| 1395 |
|
|
BUG_ON(ni->name_len);
|
| 1396 |
|
|
// TODO: Implement and replace this with
|
| 1397 |
|
|
// return ntfs_write_compressed_block(page);
|
| 1398 |
|
|
unlock_page(page);
|
| 1399 |
|
|
ntfs_error(vi->i_sb, "Writing to compressed files is "
|
| 1400 |
|
|
"not supported yet. Sorry.");
|
| 1401 |
|
|
return -EOPNOTSUPP;
|
| 1402 |
|
|
}
|
| 1403 |
|
|
// TODO: Implement and remove this check.
|
| 1404 |
|
|
if (NInoNonResident(ni) && NInoSparse(ni)) {
|
| 1405 |
|
|
unlock_page(page);
|
| 1406 |
|
|
ntfs_error(vi->i_sb, "Writing to sparse files is not "
|
| 1407 |
|
|
"supported yet. Sorry.");
|
| 1408 |
|
|
return -EOPNOTSUPP;
|
| 1409 |
|
|
}
|
| 1410 |
|
|
}
|
| 1411 |
|
|
/* NInoNonResident() == NInoIndexAllocPresent() */
|
| 1412 |
|
|
if (NInoNonResident(ni)) {
|
| 1413 |
|
|
/* We have to zero every time due to mmap-at-end-of-file. */
|
| 1414 |
|
|
if (page->index >= (i_size >> PAGE_CACHE_SHIFT)) {
|
| 1415 |
|
|
/* The page straddles i_size. */
|
| 1416 |
|
|
unsigned int ofs = i_size & ~PAGE_CACHE_MASK;
|
| 1417 |
|
|
zero_user_page(page, ofs, PAGE_CACHE_SIZE - ofs,
|
| 1418 |
|
|
KM_USER0);
|
| 1419 |
|
|
}
|
| 1420 |
|
|
/* Handle mst protected attributes. */
|
| 1421 |
|
|
if (NInoMstProtected(ni))
|
| 1422 |
|
|
return ntfs_write_mst_block(page, wbc);
|
| 1423 |
|
|
/* Normal, non-resident data stream. */
|
| 1424 |
|
|
return ntfs_write_block(page, wbc);
|
| 1425 |
|
|
}
|
| 1426 |
|
|
/*
|
| 1427 |
|
|
* Attribute is resident, implying it is not compressed, encrypted, or
|
| 1428 |
|
|
* mst protected. This also means the attribute is smaller than an mft
|
| 1429 |
|
|
* record and hence smaller than a page, so can simply return error on
|
| 1430 |
|
|
* any pages with index above 0. Note the attribute can actually be
|
| 1431 |
|
|
* marked compressed but if it is resident the actual data is not
|
| 1432 |
|
|
* compressed so we are ok to ignore the compressed flag here.
|
| 1433 |
|
|
*/
|
| 1434 |
|
|
BUG_ON(page_has_buffers(page));
|
| 1435 |
|
|
BUG_ON(!PageUptodate(page));
|
| 1436 |
|
|
if (unlikely(page->index > 0)) {
|
| 1437 |
|
|
ntfs_error(vi->i_sb, "BUG()! page->index (0x%lx) > 0. "
|
| 1438 |
|
|
"Aborting write.", page->index);
|
| 1439 |
|
|
BUG_ON(PageWriteback(page));
|
| 1440 |
|
|
set_page_writeback(page);
|
| 1441 |
|
|
unlock_page(page);
|
| 1442 |
|
|
end_page_writeback(page);
|
| 1443 |
|
|
return -EIO;
|
| 1444 |
|
|
}
|
| 1445 |
|
|
if (!NInoAttr(ni))
|
| 1446 |
|
|
base_ni = ni;
|
| 1447 |
|
|
else
|
| 1448 |
|
|
base_ni = ni->ext.base_ntfs_ino;
|
| 1449 |
|
|
/* Map, pin, and lock the mft record. */
|
| 1450 |
|
|
m = map_mft_record(base_ni);
|
| 1451 |
|
|
if (IS_ERR(m)) {
|
| 1452 |
|
|
err = PTR_ERR(m);
|
| 1453 |
|
|
m = NULL;
|
| 1454 |
|
|
ctx = NULL;
|
| 1455 |
|
|
goto err_out;
|
| 1456 |
|
|
}
|
| 1457 |
|
|
/*
|
| 1458 |
|
|
* If a parallel write made the attribute non-resident, drop the mft
|
| 1459 |
|
|
* record and retry the writepage.
|
| 1460 |
|
|
*/
|
| 1461 |
|
|
if (unlikely(NInoNonResident(ni))) {
|
| 1462 |
|
|
unmap_mft_record(base_ni);
|
| 1463 |
|
|
goto retry_writepage;
|
| 1464 |
|
|
}
|
| 1465 |
|
|
ctx = ntfs_attr_get_search_ctx(base_ni, m);
|
| 1466 |
|
|
if (unlikely(!ctx)) {
|
| 1467 |
|
|
err = -ENOMEM;
|
| 1468 |
|
|
goto err_out;
|
| 1469 |
|
|
}
|
| 1470 |
|
|
err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
|
| 1471 |
|
|
CASE_SENSITIVE, 0, NULL, 0, ctx);
|
| 1472 |
|
|
if (unlikely(err))
|
| 1473 |
|
|
goto err_out;
|
| 1474 |
|
|
/*
|
| 1475 |
|
|
* Keep the VM happy. This must be done otherwise the radix-tree tag
|
| 1476 |
|
|
* PAGECACHE_TAG_DIRTY remains set even though the page is clean.
|
| 1477 |
|
|
*/
|
| 1478 |
|
|
BUG_ON(PageWriteback(page));
|
| 1479 |
|
|
set_page_writeback(page);
|
| 1480 |
|
|
unlock_page(page);
|
| 1481 |
|
|
attr_len = le32_to_cpu(ctx->attr->data.resident.value_length);
|
| 1482 |
|
|
i_size = i_size_read(vi);
|
| 1483 |
|
|
if (unlikely(attr_len > i_size)) {
|
| 1484 |
|
|
/* Race with shrinking truncate or a failed truncate. */
|
| 1485 |
|
|
attr_len = i_size;
|
| 1486 |
|
|
/*
|
| 1487 |
|
|
* If the truncate failed, fix it up now. If a concurrent
|
| 1488 |
|
|
* truncate, we do its job, so it does not have to do anything.
|
| 1489 |
|
|
*/
|
| 1490 |
|
|
err = ntfs_resident_attr_value_resize(ctx->mrec, ctx->attr,
|
| 1491 |
|
|
attr_len);
|
| 1492 |
|
|
/* Shrinking cannot fail. */
|
| 1493 |
|
|
BUG_ON(err);
|
| 1494 |
|
|
}
|
| 1495 |
|
|
addr = kmap_atomic(page, KM_USER0);
|
| 1496 |
|
|
/* Copy the data from the page to the mft record. */
|
| 1497 |
|
|
memcpy((u8*)ctx->attr +
|
| 1498 |
|
|
le16_to_cpu(ctx->attr->data.resident.value_offset),
|
| 1499 |
|
|
addr, attr_len);
|
| 1500 |
|
|
/* Zero out of bounds area in the page cache page. */
|
| 1501 |
|
|
memset(addr + attr_len, 0, PAGE_CACHE_SIZE - attr_len);
|
| 1502 |
|
|
kunmap_atomic(addr, KM_USER0);
|
| 1503 |
|
|
flush_dcache_page(page);
|
| 1504 |
|
|
flush_dcache_mft_record_page(ctx->ntfs_ino);
|
| 1505 |
|
|
/* We are done with the page. */
|
| 1506 |
|
|
end_page_writeback(page);
|
| 1507 |
|
|
/* Finally, mark the mft record dirty, so it gets written back. */
|
| 1508 |
|
|
mark_mft_record_dirty(ctx->ntfs_ino);
|
| 1509 |
|
|
ntfs_attr_put_search_ctx(ctx);
|
| 1510 |
|
|
unmap_mft_record(base_ni);
|
| 1511 |
|
|
return 0;
|
| 1512 |
|
|
err_out:
|
| 1513 |
|
|
if (err == -ENOMEM) {
|
| 1514 |
|
|
ntfs_warning(vi->i_sb, "Error allocating memory. Redirtying "
|
| 1515 |
|
|
"page so we try again later.");
|
| 1516 |
|
|
/*
|
| 1517 |
|
|
* Put the page back on mapping->dirty_pages, but leave its
|
| 1518 |
|
|
* buffers' dirty state as-is.
|
| 1519 |
|
|
*/
|
| 1520 |
|
|
redirty_page_for_writepage(wbc, page);
|
| 1521 |
|
|
err = 0;
|
| 1522 |
|
|
} else {
|
| 1523 |
|
|
ntfs_error(vi->i_sb, "Resident attribute write failed with "
|
| 1524 |
|
|
"error %i.", err);
|
| 1525 |
|
|
SetPageError(page);
|
| 1526 |
|
|
NVolSetErrors(ni->vol);
|
| 1527 |
|
|
}
|
| 1528 |
|
|
unlock_page(page);
|
| 1529 |
|
|
if (ctx)
|
| 1530 |
|
|
ntfs_attr_put_search_ctx(ctx);
|
| 1531 |
|
|
if (m)
|
| 1532 |
|
|
unmap_mft_record(base_ni);
|
| 1533 |
|
|
return err;
|
| 1534 |
|
|
}
|
| 1535 |
|
|
|
| 1536 |
|
|
#endif /* NTFS_RW */
|
| 1537 |
|
|
|
| 1538 |
|
|
/**
|
| 1539 |
|
|
* ntfs_aops - general address space operations for inodes and attributes
|
| 1540 |
|
|
*/
|
| 1541 |
|
|
const struct address_space_operations ntfs_aops = {
|
| 1542 |
|
|
.readpage = ntfs_readpage, /* Fill page with data. */
|
| 1543 |
|
|
.sync_page = block_sync_page, /* Currently, just unplugs the
|
| 1544 |
|
|
disk request queue. */
|
| 1545 |
|
|
#ifdef NTFS_RW
|
| 1546 |
|
|
.writepage = ntfs_writepage, /* Write dirty page to disk. */
|
| 1547 |
|
|
#endif /* NTFS_RW */
|
| 1548 |
|
|
.migratepage = buffer_migrate_page, /* Move a page cache page from
|
| 1549 |
|
|
one physical page to an
|
| 1550 |
|
|
other. */
|
| 1551 |
|
|
};
|
| 1552 |
|
|
|
| 1553 |
|
|
/**
|
| 1554 |
|
|
* ntfs_mst_aops - general address space operations for mst protecteed inodes
|
| 1555 |
|
|
* and attributes
|
| 1556 |
|
|
*/
|
| 1557 |
|
|
const struct address_space_operations ntfs_mst_aops = {
|
| 1558 |
|
|
.readpage = ntfs_readpage, /* Fill page with data. */
|
| 1559 |
|
|
.sync_page = block_sync_page, /* Currently, just unplugs the
|
| 1560 |
|
|
disk request queue. */
|
| 1561 |
|
|
#ifdef NTFS_RW
|
| 1562 |
|
|
.writepage = ntfs_writepage, /* Write dirty page to disk. */
|
| 1563 |
|
|
.set_page_dirty = __set_page_dirty_nobuffers, /* Set the page dirty
|
| 1564 |
|
|
without touching the buffers
|
| 1565 |
|
|
belonging to the page. */
|
| 1566 |
|
|
#endif /* NTFS_RW */
|
| 1567 |
|
|
.migratepage = buffer_migrate_page, /* Move a page cache page from
|
| 1568 |
|
|
one physical page to an
|
| 1569 |
|
|
other. */
|
| 1570 |
|
|
};
|
| 1571 |
|
|
|
| 1572 |
|
|
#ifdef NTFS_RW
|
| 1573 |
|
|
|
| 1574 |
|
|
/**
|
| 1575 |
|
|
* mark_ntfs_record_dirty - mark an ntfs record dirty
|
| 1576 |
|
|
* @page: page containing the ntfs record to mark dirty
|
| 1577 |
|
|
* @ofs: byte offset within @page at which the ntfs record begins
|
| 1578 |
|
|
*
|
| 1579 |
|
|
* Set the buffers and the page in which the ntfs record is located dirty.
|
| 1580 |
|
|
*
|
| 1581 |
|
|
* The latter also marks the vfs inode the ntfs record belongs to dirty
|
| 1582 |
|
|
* (I_DIRTY_PAGES only).
|
| 1583 |
|
|
*
|
| 1584 |
|
|
* If the page does not have buffers, we create them and set them uptodate.
|
| 1585 |
|
|
* The page may not be locked which is why we need to handle the buffers under
|
| 1586 |
|
|
* the mapping->private_lock. Once the buffers are marked dirty we no longer
|
| 1587 |
|
|
* need the lock since try_to_free_buffers() does not free dirty buffers.
|
| 1588 |
|
|
*/
|
| 1589 |
|
|
void mark_ntfs_record_dirty(struct page *page, const unsigned int ofs) {
|
| 1590 |
|
|
struct address_space *mapping = page->mapping;
|
| 1591 |
|
|
ntfs_inode *ni = NTFS_I(mapping->host);
|
| 1592 |
|
|
struct buffer_head *bh, *head, *buffers_to_free = NULL;
|
| 1593 |
|
|
unsigned int end, bh_size, bh_ofs;
|
| 1594 |
|
|
|
| 1595 |
|
|
BUG_ON(!PageUptodate(page));
|
| 1596 |
|
|
end = ofs + ni->itype.index.block_size;
|
| 1597 |
|
|
bh_size = VFS_I(ni)->i_sb->s_blocksize;
|
| 1598 |
|
|
spin_lock(&mapping->private_lock);
|
| 1599 |
|
|
if (unlikely(!page_has_buffers(page))) {
|
| 1600 |
|
|
spin_unlock(&mapping->private_lock);
|
| 1601 |
|
|
bh = head = alloc_page_buffers(page, bh_size, 1);
|
| 1602 |
|
|
spin_lock(&mapping->private_lock);
|
| 1603 |
|
|
if (likely(!page_has_buffers(page))) {
|
| 1604 |
|
|
struct buffer_head *tail;
|
| 1605 |
|
|
|
| 1606 |
|
|
do {
|
| 1607 |
|
|
set_buffer_uptodate(bh);
|
| 1608 |
|
|
tail = bh;
|
| 1609 |
|
|
bh = bh->b_this_page;
|
| 1610 |
|
|
} while (bh);
|
| 1611 |
|
|
tail->b_this_page = head;
|
| 1612 |
|
|
attach_page_buffers(page, head);
|
| 1613 |
|
|
} else
|
| 1614 |
|
|
buffers_to_free = bh;
|
| 1615 |
|
|
}
|
| 1616 |
|
|
bh = head = page_buffers(page);
|
| 1617 |
|
|
BUG_ON(!bh);
|
| 1618 |
|
|
do {
|
| 1619 |
|
|
bh_ofs = bh_offset(bh);
|
| 1620 |
|
|
if (bh_ofs + bh_size <= ofs)
|
| 1621 |
|
|
continue;
|
| 1622 |
|
|
if (unlikely(bh_ofs >= end))
|
| 1623 |
|
|
break;
|
| 1624 |
|
|
set_buffer_dirty(bh);
|
| 1625 |
|
|
} while ((bh = bh->b_this_page) != head);
|
| 1626 |
|
|
spin_unlock(&mapping->private_lock);
|
| 1627 |
|
|
__set_page_dirty_nobuffers(page);
|
| 1628 |
|
|
if (unlikely(buffers_to_free)) {
|
| 1629 |
|
|
do {
|
| 1630 |
|
|
bh = buffers_to_free->b_this_page;
|
| 1631 |
|
|
free_buffer_head(buffers_to_free);
|
| 1632 |
|
|
buffers_to_free = bh;
|
| 1633 |
|
|
} while (buffers_to_free);
|
| 1634 |
|
|
}
|
| 1635 |
|
|
}
|
| 1636 |
|
|
|
| 1637 |
|
|
#endif /* NTFS_RW */
|
