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linux/fs/ntfs/mft.c
Kirill A. Shutemov 09cbfeaf1a mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros 
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04 10:41:08 -07:00

2918 lines
99 KiB
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/**
* mft.c - NTFS kernel mft record operations. Part of the Linux-NTFS project.
*
* Copyright (c) 2001-2012 Anton Altaparmakov and Tuxera Inc.
* Copyright (c) 2002 Richard Russon
*
* This program/include file is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as published
* by the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program/include file is distributed in the hope that it will be
* useful, but WITHOUT ANY WARRANTY; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program (in the main directory of the Linux-NTFS
* distribution in the file COPYING); if not, write to the Free Software
* Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/buffer_head.h>
#include <linux/slab.h>
#include <linux/swap.h>
#include "attrib.h"
#include "aops.h"
#include "bitmap.h"
#include "debug.h"
#include "dir.h"
#include "lcnalloc.h"
#include "malloc.h"
#include "mft.h"
#include "ntfs.h"
/**
* map_mft_record_page - map the page in which a specific mft record resides
* @ni: ntfs inode whose mft record page to map
*
* This maps the page in which the mft record of the ntfs inode @ni is situated
* and returns a pointer to the mft record within the mapped page.
*
* Return value needs to be checked with IS_ERR() and if that is true PTR_ERR()
* contains the negative error code returned.
*/
static inline MFT_RECORD *map_mft_record_page(ntfs_inode *ni)
{
loff_t i_size;
ntfs_volume *vol = ni->vol;
struct inode *mft_vi = vol->mft_ino;
struct page *page;
unsigned long index, end_index;
unsigned ofs;
BUG_ON(ni->page);
/*
* The index into the page cache and the offset within the page cache
* page of the wanted mft record. FIXME: We need to check for
* overflowing the unsigned long, but I don't think we would ever get
* here if the volume was that big...
*/
index = (u64)ni->mft_no << vol->mft_record_size_bits >>
PAGE_SHIFT;
ofs = (ni->mft_no << vol->mft_record_size_bits) & ~PAGE_MASK;
i_size = i_size_read(mft_vi);
/* The maximum valid index into the page cache for $MFT's data. */
end_index = i_size >> PAGE_SHIFT;
/* If the wanted index is out of bounds the mft record doesn't exist. */
if (unlikely(index >= end_index)) {
if (index > end_index || (i_size & ~PAGE_MASK) < ofs +
vol->mft_record_size) {
page = ERR_PTR(-ENOENT);
ntfs_error(vol->sb, "Attempt to read mft record 0x%lx, "
"which is beyond the end of the mft. "
"This is probably a bug in the ntfs "
"driver.", ni->mft_no);
goto err_out;
}
}
/* Read, map, and pin the page. */
page = ntfs_map_page(mft_vi->i_mapping, index);
if (likely(!IS_ERR(page))) {
/* Catch multi sector transfer fixup errors. */
if (likely(ntfs_is_mft_recordp((le32*)(page_address(page) +
ofs)))) {
ni->page = page;
ni->page_ofs = ofs;
return page_address(page) + ofs;
}
ntfs_error(vol->sb, "Mft record 0x%lx is corrupt. "
"Run chkdsk.", ni->mft_no);
ntfs_unmap_page(page);
page = ERR_PTR(-EIO);
NVolSetErrors(vol);
}
err_out:
ni->page = NULL;
ni->page_ofs = 0;
return (void*)page;
}
/**
* map_mft_record - map, pin and lock an mft record
* @ni: ntfs inode whose MFT record to map
*
* First, take the mrec_lock mutex. We might now be sleeping, while waiting
* for the mutex if it was already locked by someone else.
*
* The page of the record is mapped using map_mft_record_page() before being
* returned to the caller.
*
* This in turn uses ntfs_map_page() to get the page containing the wanted mft
* record (it in turn calls read_cache_page() which reads it in from disk if
* necessary, increments the use count on the page so that it cannot disappear
* under us and returns a reference to the page cache page).
*
* If read_cache_page() invokes ntfs_readpage() to load the page from disk, it
* sets PG_locked and clears PG_uptodate on the page. Once I/O has completed
* and the post-read mst fixups on each mft record in the page have been
* performed, the page gets PG_uptodate set and PG_locked cleared (this is done
* in our asynchronous I/O completion handler end_buffer_read_mft_async()).
* ntfs_map_page() waits for PG_locked to become clear and checks if
* PG_uptodate is set and returns an error code if not. This provides
* sufficient protection against races when reading/using the page.
*
* However there is the write mapping to think about. Doing the above described
* checking here will be fine, because when initiating the write we will set
* PG_locked and clear PG_uptodate making sure nobody is touching the page
* contents. Doing the locking this way means that the commit to disk code in
* the page cache code paths is automatically sufficiently locked with us as
* we will not touch a page that has been locked or is not uptodate. The only
* locking problem then is them locking the page while we are accessing it.
*
* So that code will end up having to own the mrec_lock of all mft
* records/inodes present in the page before I/O can proceed. In that case we
* wouldn't need to bother with PG_locked and PG_uptodate as nobody will be
* accessing anything without owning the mrec_lock mutex. But we do need to
* use them because of the read_cache_page() invocation and the code becomes so
* much simpler this way that it is well worth it.
*
* The mft record is now ours and we return a pointer to it. You need to check
* the returned pointer with IS_ERR() and if that is true, PTR_ERR() will return
* the error code.
*
* NOTE: Caller is responsible for setting the mft record dirty before calling
* unmap_mft_record(). This is obviously only necessary if the caller really
* modified the mft record...
* Q: Do we want to recycle one of the VFS inode state bits instead?
* A: No, the inode ones mean we want to change the mft record, not we want to
* write it out.
*/
MFT_RECORD *map_mft_record(ntfs_inode *ni)
{
MFT_RECORD *m;
ntfs_debug("Entering for mft_no 0x%lx.", ni->mft_no);
/* Make sure the ntfs inode doesn't go away. */
atomic_inc(&ni->count);
/* Serialize access to this mft record. */
mutex_lock(&ni->mrec_lock);
m = map_mft_record_page(ni);
if (likely(!IS_ERR(m)))
return m;
mutex_unlock(&ni->mrec_lock);
atomic_dec(&ni->count);
ntfs_error(ni->vol->sb, "Failed with error code %lu.", -PTR_ERR(m));
return m;
}
/**
* unmap_mft_record_page - unmap the page in which a specific mft record resides
* @ni: ntfs inode whose mft record page to unmap
*
* This unmaps the page in which the mft record of the ntfs inode @ni is
* situated and returns. This is a NOOP if highmem is not configured.
*
* The unmap happens via ntfs_unmap_page() which in turn decrements the use
* count on the page thus releasing it from the pinned state.
*
* We do not actually unmap the page from memory of course, as that will be
* done by the page cache code itself when memory pressure increases or
* whatever.
*/
static inline void unmap_mft_record_page(ntfs_inode *ni)
{
BUG_ON(!ni->page);
// TODO: If dirty, blah...
ntfs_unmap_page(ni->page);
ni->page = NULL;
ni->page_ofs = 0;
return;
}
/**
* unmap_mft_record - release a mapped mft record
* @ni: ntfs inode whose MFT record to unmap
*
* We release the page mapping and the mrec_lock mutex which unmaps the mft
* record and releases it for others to get hold of. We also release the ntfs
* inode by decrementing the ntfs inode reference count.
*
* NOTE: If caller has modified the mft record, it is imperative to set the mft
* record dirty BEFORE calling unmap_mft_record().
*/
void unmap_mft_record(ntfs_inode *ni)
{
struct page *page = ni->page;
BUG_ON(!page);
ntfs_debug("Entering for mft_no 0x%lx.", ni->mft_no);
unmap_mft_record_page(ni);
mutex_unlock(&ni->mrec_lock);
atomic_dec(&ni->count);
/*
* If pure ntfs_inode, i.e. no vfs inode attached, we leave it to
* ntfs_clear_extent_inode() in the extent inode case, and to the
* caller in the non-extent, yet pure ntfs inode case, to do the actual
* tear down of all structures and freeing of all allocated memory.
*/
return;
}
/**
* map_extent_mft_record - load an extent inode and attach it to its base
* @base_ni: base ntfs inode
* @mref: mft reference of the extent inode to load
* @ntfs_ino: on successful return, pointer to the ntfs_inode structure
*
* Load the extent mft record @mref and attach it to its base inode @base_ni.
* Return the mapped extent mft record if IS_ERR(result) is false. Otherwise
* PTR_ERR(result) gives the negative error code.
*
* On successful return, @ntfs_ino contains a pointer to the ntfs_inode
* structure of the mapped extent inode.
*/
MFT_RECORD *map_extent_mft_record(ntfs_inode *base_ni, MFT_REF mref,
ntfs_inode **ntfs_ino)
{
MFT_RECORD *m;
ntfs_inode *ni = NULL;
ntfs_inode **extent_nis = NULL;
int i;
unsigned long mft_no = MREF(mref);
u16 seq_no = MSEQNO(mref);
bool destroy_ni = false;
ntfs_debug("Mapping extent mft record 0x%lx (base mft record 0x%lx).",
mft_no, base_ni->mft_no);
/* Make sure the base ntfs inode doesn't go away. */
atomic_inc(&base_ni->count);
/*
* Check if this extent inode has already been added to the base inode,
* in which case just return it. If not found, add it to the base
* inode before returning it.
*/
mutex_lock(&base_ni->extent_lock);
if (base_ni->nr_extents > 0) {
extent_nis = base_ni->ext.extent_ntfs_inos;
for (i = 0; i < base_ni->nr_extents; i++) {
if (mft_no != extent_nis[i]->mft_no)
continue;
ni = extent_nis[i];
/* Make sure the ntfs inode doesn't go away. */
atomic_inc(&ni->count);
break;
}
}
if (likely(ni != NULL)) {
mutex_unlock(&base_ni->extent_lock);
atomic_dec(&base_ni->count);
/* We found the record; just have to map and return it. */
m = map_mft_record(ni);
/* map_mft_record() has incremented this on success. */
atomic_dec(&ni->count);
if (likely(!IS_ERR(m))) {
/* Verify the sequence number. */
if (likely(le16_to_cpu(m->sequence_number) == seq_no)) {
ntfs_debug("Done 1.");
*ntfs_ino = ni;
return m;
}
unmap_mft_record(ni);
ntfs_error(base_ni->vol->sb, "Found stale extent mft "
"reference! Corrupt filesystem. "
"Run chkdsk.");
return ERR_PTR(-EIO);
}
map_err_out:
ntfs_error(base_ni->vol->sb, "Failed to map extent "
"mft record, error code %ld.", -PTR_ERR(m));
return m;
}
/* Record wasn't there. Get a new ntfs inode and initialize it. */
ni = ntfs_new_extent_inode(base_ni->vol->sb, mft_no);
if (unlikely(!ni)) {
mutex_unlock(&base_ni->extent_lock);
atomic_dec(&base_ni->count);
return ERR_PTR(-ENOMEM);
}
ni->vol = base_ni->vol;
ni->seq_no = seq_no;
ni->nr_extents = -1;
ni->ext.base_ntfs_ino = base_ni;
/* Now map the record. */
m = map_mft_record(ni);
if (IS_ERR(m)) {
mutex_unlock(&base_ni->extent_lock);
atomic_dec(&base_ni->count);
ntfs_clear_extent_inode(ni);
goto map_err_out;
}
/* Verify the sequence number if it is present. */
if (seq_no && (le16_to_cpu(m->sequence_number) != seq_no)) {
ntfs_error(base_ni->vol->sb, "Found stale extent mft "
"reference! Corrupt filesystem. Run chkdsk.");
destroy_ni = true;
m = ERR_PTR(-EIO);
goto unm_err_out;
}
/* Attach extent inode to base inode, reallocating memory if needed. */
if (!(base_ni->nr_extents & 3)) {
ntfs_inode **tmp;
int new_size = (base_ni->nr_extents + 4) * sizeof(ntfs_inode *);
tmp = kmalloc(new_size, GFP_NOFS);
if (unlikely(!tmp)) {
ntfs_error(base_ni->vol->sb, "Failed to allocate "
"internal buffer.");
destroy_ni = true;
m = ERR_PTR(-ENOMEM);
goto unm_err_out;
}
if (base_ni->nr_extents) {
BUG_ON(!base_ni->ext.extent_ntfs_inos);
memcpy(tmp, base_ni->ext.extent_ntfs_inos, new_size -
4 * sizeof(ntfs_inode *));
kfree(base_ni->ext.extent_ntfs_inos);
}
base_ni->ext.extent_ntfs_inos = tmp;
}
base_ni->ext.extent_ntfs_inos[base_ni->nr_extents++] = ni;
mutex_unlock(&base_ni->extent_lock);
atomic_dec(&base_ni->count);
ntfs_debug("Done 2.");
*ntfs_ino = ni;
return m;
unm_err_out:
unmap_mft_record(ni);
mutex_unlock(&base_ni->extent_lock);
atomic_dec(&base_ni->count);
/*
* If the extent inode was not attached to the base inode we need to
* release it or we will leak memory.
*/
if (destroy_ni)
ntfs_clear_extent_inode(ni);
return m;
}
#ifdef NTFS_RW
/**
* __mark_mft_record_dirty - set the mft record and the page containing it dirty
* @ni: ntfs inode describing the mapped mft record
*
* Internal function. Users should call mark_mft_record_dirty() instead.
*
* Set the mapped (extent) mft record of the (base or extent) ntfs inode @ni,
* as well as the page containing the mft record, dirty. Also, mark the base
* vfs inode dirty. This ensures that any changes to the mft record are
* written out to disk.
*
* NOTE: We only set I_DIRTY_SYNC and I_DIRTY_DATASYNC (and not I_DIRTY_PAGES)
* on the base vfs inode, because even though file data may have been modified,
* it is dirty in the inode meta data rather than the data page cache of the
* inode, and thus there are no data pages that need writing out. Therefore, a
* full mark_inode_dirty() is overkill. A mark_inode_dirty_sync(), on the
* other hand, is not sufficient, because ->write_inode needs to be called even
* in case of fdatasync. This needs to happen or the file data would not
* necessarily hit the device synchronously, even though the vfs inode has the
* O_SYNC flag set. Also, I_DIRTY_DATASYNC simply "feels" better than just
* I_DIRTY_SYNC, since the file data has not actually hit the block device yet,
* which is not what I_DIRTY_SYNC on its own would suggest.
*/
void __mark_mft_record_dirty(ntfs_inode *ni)
{
ntfs_inode *base_ni;
ntfs_debug("Entering for inode 0x%lx.", ni->mft_no);
BUG_ON(NInoAttr(ni));
mark_ntfs_record_dirty(ni->page, ni->page_ofs);
/* Determine the base vfs inode and mark it dirty, too. */
mutex_lock(&ni->extent_lock);
if (likely(ni->nr_extents >= 0))
base_ni = ni;
else
base_ni = ni->ext.base_ntfs_ino;
mutex_unlock(&ni->extent_lock);
__mark_inode_dirty(VFS_I(base_ni), I_DIRTY_SYNC | I_DIRTY_DATASYNC);
}
static const char *ntfs_please_email = "Please email "
"linux-ntfs-dev@lists.sourceforge.net and say that you saw "
"this message. Thank you.";
/**
* ntfs_sync_mft_mirror_umount - synchronise an mft record to the mft mirror
* @vol: ntfs volume on which the mft record to synchronize resides
* @mft_no: mft record number of mft record to synchronize
* @m: mapped, mst protected (extent) mft record to synchronize
*
* Write the mapped, mst protected (extent) mft record @m with mft record
* number @mft_no to the mft mirror ($MFTMirr) of the ntfs volume @vol,
* bypassing the page cache and the $MFTMirr inode itself.
*
* This function is only for use at umount time when the mft mirror inode has
* already been disposed off. We BUG() if we are called while the mft mirror
* inode is still attached to the volume.
*
* On success return 0. On error return -errno.
*
* NOTE: This function is not implemented yet as I am not convinced it can
* actually be triggered considering the sequence of commits we do in super.c::
* ntfs_put_super(). But just in case we provide this place holder as the
* alternative would be either to BUG() or to get a NULL pointer dereference
* and Oops.
*/
static int ntfs_sync_mft_mirror_umount(ntfs_volume *vol,
const unsigned long mft_no, MFT_RECORD *m)
{
BUG_ON(vol->mftmirr_ino);
ntfs_error(vol->sb, "Umount time mft mirror syncing is not "
"implemented yet. %s", ntfs_please_email);
return -EOPNOTSUPP;
}
/**
* ntfs_sync_mft_mirror - synchronize an mft record to the mft mirror
* @vol: ntfs volume on which the mft record to synchronize resides
* @mft_no: mft record number of mft record to synchronize
* @m: mapped, mst protected (extent) mft record to synchronize
* @sync: if true, wait for i/o completion
*
* Write the mapped, mst protected (extent) mft record @m with mft record
* number @mft_no to the mft mirror ($MFTMirr) of the ntfs volume @vol.
*
* On success return 0. On error return -errno and set the volume errors flag
* in the ntfs volume @vol.
*
* NOTE: We always perform synchronous i/o and ignore the @sync parameter.
*
* TODO: If @sync is false, want to do truly asynchronous i/o, i.e. just
* schedule i/o via ->writepage or do it via kntfsd or whatever.
*/
int ntfs_sync_mft_mirror(ntfs_volume *vol, const unsigned long mft_no,
MFT_RECORD *m, int sync)
{
struct page *page;
unsigned int blocksize = vol->sb->s_blocksize;
int max_bhs = vol->mft_record_size / blocksize;
struct buffer_head *bhs[max_bhs];
struct buffer_head *bh, *head;
u8 *kmirr;
runlist_element *rl;
unsigned int block_start, block_end, m_start, m_end, page_ofs;
int i_bhs, nr_bhs, err = 0;
unsigned char blocksize_bits = vol->sb->s_blocksize_bits;
ntfs_debug("Entering for inode 0x%lx.", mft_no);
BUG_ON(!max_bhs);
if (unlikely(!vol->mftmirr_ino)) {
/* This could happen during umount... */
err = ntfs_sync_mft_mirror_umount(vol, mft_no, m);
if (likely(!err))
return err;
goto err_out;
}
/* Get the page containing the mirror copy of the mft record @m. */
page = ntfs_map_page(vol->mftmirr_ino->i_mapping, mft_no >>
(PAGE_SHIFT - vol->mft_record_size_bits));
if (IS_ERR(page)) {
ntfs_error(vol->sb, "Failed to map mft mirror page.");
err = PTR_ERR(page);
goto err_out;
}
lock_page(page);
BUG_ON(!PageUptodate(page));
ClearPageUptodate(page);
/* Offset of the mft mirror record inside the page. */
page_ofs = (mft_no << vol->mft_record_size_bits) & ~PAGE_MASK;
/* The address in the page of the mirror copy of the mft record @m. */
kmirr = page_address(page) + page_ofs;
/* Copy the mst protected mft record to the mirror. */
memcpy(kmirr, m, vol->mft_record_size);
/* Create uptodate buffers if not present. */
if (unlikely(!page_has_buffers(page))) {
struct buffer_head *tail;
bh = head = alloc_page_buffers(page, blocksize, 1);
do {
set_buffer_uptodate(bh);
tail = bh;
bh = bh->b_this_page;
} while (bh);
tail->b_this_page = head;
attach_page_buffers(page, head);
}
bh = head = page_buffers(page);
BUG_ON(!bh);
rl = NULL;
nr_bhs = 0;
block_start = 0;
m_start = kmirr - (u8*)page_address(page);
m_end = m_start + vol->mft_record_size;
do {
block_end = block_start + blocksize;
/* If the buffer is outside the mft record, skip it. */
if (block_end <= m_start)
continue;
if (unlikely(block_start >= m_end))
break;
/* Need to map the buffer if it is not mapped already. */
if (unlikely(!buffer_mapped(bh))) {
VCN vcn;
LCN lcn;
unsigned int vcn_ofs;
bh->b_bdev = vol->sb->s_bdev;
/* Obtain the vcn and offset of the current block. */
vcn = ((VCN)mft_no << vol->mft_record_size_bits) +
(block_start - m_start);
vcn_ofs = vcn & vol->cluster_size_mask;
vcn >>= vol->cluster_size_bits;
if (!rl) {
down_read(&NTFS_I(vol->mftmirr_ino)->
runlist.lock);
rl = NTFS_I(vol->mftmirr_ino)->runlist.rl;
/*
* $MFTMirr always has the whole of its runlist
* in memory.
*/
BUG_ON(!rl);
}
/* Seek to element containing target vcn. */
while (rl->length && rl[1].vcn <= vcn)
rl++;
lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
/* For $MFTMirr, only lcn >= 0 is a successful remap. */
if (likely(lcn >= 0)) {
/* Setup buffer head to correct block. */
bh->b_blocknr = ((lcn <<
vol->cluster_size_bits) +
vcn_ofs) >> blocksize_bits;
set_buffer_mapped(bh);
} else {
bh->b_blocknr = -1;
ntfs_error(vol->sb, "Cannot write mft mirror "
"record 0x%lx because its "
"location on disk could not "
"be determined (error code "
"%lli).", mft_no,
(long long)lcn);
err = -EIO;
}
}
BUG_ON(!buffer_uptodate(bh));
BUG_ON(!nr_bhs && (m_start != block_start));
BUG_ON(nr_bhs >= max_bhs);
bhs[nr_bhs++] = bh;
BUG_ON((nr_bhs >= max_bhs) && (m_end != block_end));
} while (block_start = block_end, (bh = bh->b_this_page) != head);
if (unlikely(rl))
up_read(&NTFS_I(vol->mftmirr_ino)->runlist.lock);
if (likely(!err)) {
/* Lock buffers and start synchronous write i/o on them. */
for (i_bhs = 0; i_bhs < nr_bhs; i_bhs++) {
struct buffer_head *tbh = bhs[i_bhs];
if (!trylock_buffer(tbh))
BUG();
BUG_ON(!buffer_uptodate(tbh));
clear_buffer_dirty(tbh);
get_bh(tbh);
tbh->b_end_io = end_buffer_write_sync;
submit_bh(WRITE, tbh);
}
/* Wait on i/o completion of buffers. */
for (i_bhs = 0; i_bhs < nr_bhs; i_bhs++) {
struct buffer_head *tbh = bhs[i_bhs];
wait_on_buffer(tbh);
if (unlikely(!buffer_uptodate(tbh))) {
err = -EIO;
/*
* Set the buffer uptodate so the page and
* buffer states do not become out of sync.
*/
set_buffer_uptodate(tbh);
}
}
} else /* if (unlikely(err)) */ {
/* Clean the buffers. */
for (i_bhs = 0; i_bhs < nr_bhs; i_bhs++)
clear_buffer_dirty(bhs[i_bhs]);
}
/* Current state: all buffers are clean, unlocked, and uptodate. */
/* Remove the mst protection fixups again. */
post_write_mst_fixup((NTFS_RECORD*)kmirr);
flush_dcache_page(page);
SetPageUptodate(page);
unlock_page(page);
ntfs_unmap_page(page);
if (likely(!err)) {
ntfs_debug("Done.");
} else {
ntfs_error(vol->sb, "I/O error while writing mft mirror "
"record 0x%lx!", mft_no);
err_out:
ntfs_error(vol->sb, "Failed to synchronize $MFTMirr (error "
"code %i). Volume will be left marked dirty "
"on umount. Run ntfsfix on the partition "
"after umounting to correct this.", -err);
NVolSetErrors(vol);
}
return err;
}
/**
* write_mft_record_nolock - write out a mapped (extent) mft record
* @ni: ntfs inode describing the mapped (extent) mft record
* @m: mapped (extent) mft record to write
* @sync: if true, wait for i/o completion
*
* Write the mapped (extent) mft record @m described by the (regular or extent)
* ntfs inode @ni to backing store. If the mft record @m has a counterpart in
* the mft mirror, that is also updated.
*
* We only write the mft record if the ntfs inode @ni is dirty and the first
* buffer belonging to its mft record is dirty, too. We ignore the dirty state
* of subsequent buffers because we could have raced with
* fs/ntfs/aops.c::mark_ntfs_record_dirty().
*
* On success, clean the mft record and return 0. On error, leave the mft
* record dirty and return -errno.
*
* NOTE: We always perform synchronous i/o and ignore the @sync parameter.
* However, if the mft record has a counterpart in the mft mirror and @sync is
* true, we write the mft record, wait for i/o completion, and only then write
* the mft mirror copy. This ensures that if the system crashes either the mft
* or the mft mirror will contain a self-consistent mft record @m. If @sync is
* false on the other hand, we start i/o on both and then wait for completion
* on them. This provides a speedup but no longer guarantees that you will end
* up with a self-consistent mft record in the case of a crash but if you asked
* for asynchronous writing you probably do not care about that anyway.
*
* TODO: If @sync is false, want to do truly asynchronous i/o, i.e. just
* schedule i/o via ->writepage or do it via kntfsd or whatever.
*/
int write_mft_record_nolock(ntfs_inode *ni, MFT_RECORD *m, int sync)
{
ntfs_volume *vol = ni->vol;
struct page *page = ni->page;
unsigned int blocksize = vol->sb->s_blocksize;
unsigned char blocksize_bits = vol->sb->s_blocksize_bits;
int max_bhs = vol->mft_record_size / blocksize;
struct buffer_head *bhs[max_bhs];
struct buffer_head *bh, *head;
runlist_element *rl;
unsigned int block_start, block_end, m_start, m_end;
int i_bhs, nr_bhs, err = 0;
ntfs_debug("Entering for inode 0x%lx.", ni->mft_no);
BUG_ON(NInoAttr(ni));
BUG_ON(!max_bhs);
BUG_ON(!PageLocked(page));
/*
* If the ntfs_inode is clean no need to do anything. If it is dirty,
* mark it as clean now so that it can be redirtied later on if needed.
* There is no danger of races since the caller is holding the locks
* for the mft record @m and the page it is in.
*/
if (!NInoTestClearDirty(ni))
goto done;
bh = head = page_buffers(page);
BUG_ON(!bh);
rl = NULL;
nr_bhs = 0;
block_start = 0;
m_start = ni->page_ofs;
m_end = m_start + vol->mft_record_size;
do {
block_end = block_start + blocksize;
/* If the buffer is outside the mft record, skip it. */
if (block_end <= m_start)
continue;
if (unlikely(block_start >= m_end))
break;
/*
* If this block is not the first one in the record, we ignore
* the buffer's dirty state because we could have raced with a
* parallel mark_ntfs_record_dirty().
*/
if (block_start == m_start) {
/* This block is the first one in the record. */
if (!buffer_dirty(bh)) {
BUG_ON(nr_bhs);
/* Clean records are not written out. */
break;
}
}
/* Need to map the buffer if it is not mapped already. */
if (unlikely(!buffer_mapped(bh))) {
VCN vcn;
LCN lcn;
unsigned int vcn_ofs;
bh->b_bdev = vol->sb->s_bdev;
/* Obtain the vcn and offset of the current block. */
vcn = ((VCN)ni->mft_no << vol->mft_record_size_bits) +
(block_start - m_start);
vcn_ofs = vcn & vol->cluster_size_mask;
vcn >>= vol->cluster_size_bits;
if (!rl) {
down_read(&NTFS_I(vol->mft_ino)->runlist.lock);
rl = NTFS_I(vol->mft_ino)->runlist.rl;
BUG_ON(!rl);
}
/* Seek to element containing target vcn. */
while (rl->length && rl[1].vcn <= vcn)
rl++;
lcn = ntfs_rl_vcn_to_lcn(rl, vcn);
/* For $MFT, only lcn >= 0 is a successful remap. */
if (likely(lcn >= 0)) {
/* Setup buffer head to correct block. */
bh->b_blocknr = ((lcn <<
vol->cluster_size_bits) +
vcn_ofs) >> blocksize_bits;
set_buffer_mapped(bh);
} else {
bh->b_blocknr = -1;
ntfs_error(vol->sb, "Cannot write mft record "
"0x%lx because its location "
"on disk could not be "
"determined (error code %lli).",
ni->mft_no, (long long)lcn);
err = -EIO;
}
}
BUG_ON(!buffer_uptodate(bh));
BUG_ON(!nr_bhs && (m_start != block_start));
BUG_ON(nr_bhs >= max_bhs);
bhs[nr_bhs++] = bh;
BUG_ON((nr_bhs >= max_bhs) && (m_end != block_end));
} while (block_start = block_end, (bh = bh->b_this_page) != head);
if (unlikely(rl))
up_read(&NTFS_I(vol->mft_ino)->runlist.lock);
if (!nr_bhs)
goto done;
if (unlikely(err))
goto cleanup_out;
/* Apply the mst protection fixups. */
err = pre_write_mst_fixup((NTFS_RECORD*)m, vol->mft_record_size);
if (err) {
ntfs_error(vol->sb, "Failed to apply mst fixups!");
goto cleanup_out;
}
flush_dcache_mft_record_page(ni);
/* Lock buffers and start synchronous write i/o on them. */
for (i_bhs = 0; i_bhs < nr_bhs; i_bhs++) {
struct buffer_head *tbh = bhs[i_bhs];
if (!trylock_buffer(tbh))
BUG();
BUG_ON(!buffer_uptodate(tbh));
clear_buffer_dirty(tbh);
get_bh(tbh);
tbh->b_end_io = end_buffer_write_sync;
submit_bh(WRITE, tbh);
}
/* Synchronize the mft mirror now if not @sync. */
if (!sync && ni->mft_no < vol->mftmirr_size)
ntfs_sync_mft_mirror(vol, ni->mft_no, m, sync);
/* Wait on i/o completion of buffers. */
for (i_bhs = 0; i_bhs < nr_bhs; i_bhs++) {
struct buffer_head *tbh = bhs[i_bhs];
wait_on_buffer(tbh);
if (unlikely(!buffer_uptodate(tbh))) {
err = -EIO;
/*
* Set the buffer uptodate so the page and buffer
* states do not become out of sync.
*/
if (PageUptodate(page))
set_buffer_uptodate(tbh);
}
}
/* If @sync, now synchronize the mft mirror. */
if (sync && ni->mft_no < vol->mftmirr_size)
ntfs_sync_mft_mirror(vol, ni->mft_no, m, sync);
/* Remove the mst protection fixups again. */
post_write_mst_fixup((NTFS_RECORD*)m);
flush_dcache_mft_record_page(ni);
if (unlikely(err)) {
/* I/O error during writing. This is really bad! */
ntfs_error(vol->sb, "I/O error while writing mft record "
"0x%lx! Marking base inode as bad. You "
"should unmount the volume and run chkdsk.",
ni->mft_no);
goto err_out;
}
done:
ntfs_debug("Done.");
return 0;
cleanup_out:
/* Clean the buffers. */
for (i_bhs = 0; i_bhs < nr_bhs; i_bhs++)
clear_buffer_dirty(bhs[i_bhs]);
err_out:
/*
* Current state: all buffers are clean, unlocked, and uptodate.
* The caller should mark the base inode as bad so that no more i/o
* happens. ->clear_inode() will still be invoked so all extent inodes
* and other allocated memory will be freed.
*/
if (err == -ENOMEM) {
ntfs_error(vol->sb, "Not enough memory to write mft record. "
"Redirtying so the write is retried later.");
mark_mft_record_dirty(ni);
err = 0;
} else
NVolSetErrors(vol);
return err;
}
/**
* ntfs_may_write_mft_record - check if an mft record may be written out
* @vol: [IN] ntfs volume on which the mft record to check resides
* @mft_no: [IN] mft record number of the mft record to check
* @m: [IN] mapped mft record to check
* @locked_ni: [OUT] caller has to unlock this ntfs inode if one is returned
*
* Check if the mapped (base or extent) mft record @m with mft record number
* @mft_no belonging to the ntfs volume @vol may be written out. If necessary
* and possible the ntfs inode of the mft record is locked and the base vfs
* inode is pinned. The locked ntfs inode is then returned in @locked_ni. The
* caller is responsible for unlocking the ntfs inode and unpinning the base
* vfs inode.
*
* Return 'true' if the mft record may be written out and 'false' if not.
*
* The caller has locked the page and cleared the uptodate flag on it which
* means that we can safely write out any dirty mft records that do not have
* their inodes in icache as determined by ilookup5() as anyone
* opening/creating such an inode would block when attempting to map the mft
* record in read_cache_page() until we are finished with the write out.
*
* Here is a description of the tests we perform:
*
* If the inode is found in icache we know the mft record must be a base mft
* record. If it is dirty, we do not write it and return 'false' as the vfs
* inode write paths will result in the access times being updated which would
* cause the base mft record to be redirtied and written out again. (We know
* the access time update will modify the base mft record because Windows
* chkdsk complains if the standard information attribute is not in the base
* mft record.)
*
* If the inode is in icache and not dirty, we attempt to lock the mft record
* and if we find the lock was already taken, it is not safe to write the mft
* record and we return 'false'.
*
* If we manage to obtain the lock we have exclusive access to the mft record,
* which also allows us safe writeout of the mft record. We then set
* @locked_ni to the locked ntfs inode and return 'true'.
*
* Note we cannot just lock the mft record and sleep while waiting for the lock
* because this would deadlock due to lock reversal (normally the mft record is
* locked before the page is locked but we already have the page locked here
* when we try to lock the mft record).
*
* If the inode is not in icache we need to perform further checks.
*
* If the mft record is not a FILE record or it is a base mft record, we can
* safely write it and return 'true'.
*
* We now know the mft record is an extent mft record. We check if the inode
* corresponding to its base mft record is in icache and obtain a reference to
* it if it is. If it is not, we can safely write it and return 'true'.
*
* We now have the base inode for the extent mft record. We check if it has an
* ntfs inode for the extent mft record attached and if not it is safe to write
* the extent mft record and we return 'true'.
*
* The ntfs inode for the extent mft record is attached to the base inode so we
* attempt to lock the extent mft record and if we find the lock was already
* taken, it is not safe to write the extent mft record and we return 'false'.
*
* If we manage to obtain the lock we have exclusive access to the extent mft
* record, which also allows us safe writeout of the extent mft record. We
* set the ntfs inode of the extent mft record clean and then set @locked_ni to
* the now locked ntfs inode and return 'true'.
*
* Note, the reason for actually writing dirty mft records here and not just
* relying on the vfs inode dirty code paths is that we can have mft records
* modified without them ever having actual inodes in memory. Also we can have
* dirty mft records with clean ntfs inodes in memory. None of the described
* cases would result in the dirty mft records being written out if we only
* relied on the vfs inode dirty code paths. And these cases can really occur
* during allocation of new mft records and in particular when the
* initialized_size of the $MFT/$DATA attribute is extended and the new space
* is initialized using ntfs_mft_record_format(). The clean inode can then
* appear if the mft record is reused for a new inode before it got written
* out.
*/
bool ntfs_may_write_mft_record(ntfs_volume *vol, const unsigned long mft_no,
const MFT_RECORD *m, ntfs_inode **locked_ni)
{
struct super_block *sb = vol->sb;
struct inode *mft_vi = vol->mft_ino;
struct inode *vi;
ntfs_inode *ni, *eni, **extent_nis;
int i;
ntfs_attr na;
ntfs_debug("Entering for inode 0x%lx.", mft_no);
/*
* Normally we do not return a locked inode so set @locked_ni to NULL.
*/
BUG_ON(!locked_ni);
*locked_ni = NULL;
/*
* Check if the inode corresponding to this mft record is in the VFS
* inode cache and obtain a reference to it if it is.
*/
ntfs_debug("Looking for inode 0x%lx in icache.", mft_no);
na.mft_no = mft_no;
na.name = NULL;
na.name_len = 0;
na.type = AT_UNUSED;
/*
* Optimize inode 0, i.e. $MFT itself, since we have it in memory and
* we get here for it rather often.
*/
if (!mft_no) {
/* Balance the below iput(). */
vi = igrab(mft_vi);
BUG_ON(vi != mft_vi);
} else {
/*
* Have to use ilookup5_nowait() since ilookup5() waits for the
* inode lock which causes ntfs to deadlock when a concurrent
* inode write via the inode dirty code paths and the page
* dirty code path of the inode dirty code path when writing
* $MFT occurs.
*/
vi = ilookup5_nowait(sb, mft_no, (test_t)ntfs_test_inode, &na);
}
if (vi) {
ntfs_debug("Base inode 0x%lx is in icache.", mft_no);
/* The inode is in icache. */
ni = NTFS_I(vi);
/* Take a reference to the ntfs inode. */
atomic_inc(&ni->count);
/* If the inode is dirty, do not write this record. */
if (NInoDirty(ni)) {
ntfs_debug("Inode 0x%lx is dirty, do not write it.",
mft_no);
atomic_dec(&ni->count);
iput(vi);
return false;
}
ntfs_debug("Inode 0x%lx is not dirty.", mft_no);
/* The inode is not dirty, try to take the mft record lock. */
if (unlikely(!mutex_trylock(&ni->mrec_lock))) {
ntfs_debug("Mft record 0x%lx is already locked, do "
"not write it.", mft_no);
atomic_dec(&ni->count);
iput(vi);
return false;
}
ntfs_debug("Managed to lock mft record 0x%lx, write it.",
mft_no);
/*
* The write has to occur while we hold the mft record lock so
* return the locked ntfs inode.
*/
*locked_ni = ni;
return true;
}
ntfs_debug("Inode 0x%lx is not in icache.", mft_no);
/* The inode is not in icache. */
/* Write the record if it is not a mft record (type "FILE"). */
if (!ntfs_is_mft_record(m->magic)) {
ntfs_debug("Mft record 0x%lx is not a FILE record, write it.",
mft_no);
return true;
}
/* Write the mft record if it is a base inode. */
if (!m->base_mft_record) {
ntfs_debug("Mft record 0x%lx is a base record, write it.",
mft_no);
return true;
}
/*
* This is an extent mft record. Check if the inode corresponding to
* its base mft record is in icache and obtain a reference to it if it
* is.
*/
na.mft_no = MREF_LE(m->base_mft_record);
ntfs_debug("Mft record 0x%lx is an extent record. Looking for base "
"inode 0x%lx in icache.", mft_no, na.mft_no);
if (!na.mft_no) {
/* Balance the below iput(). */
vi = igrab(mft_vi);
BUG_ON(vi != mft_vi);
} else
vi = ilookup5_nowait(sb, na.mft_no, (test_t)ntfs_test_inode,
&na);
if (!vi) {
/*
* The base inode is not in icache, write this extent mft
* record.
*/
ntfs_debug("Base inode 0x%lx is not in icache, write the "
"extent record.", na.mft_no);
return true;
}
ntfs_debug("Base inode 0x%lx is in icache.", na.mft_no);
/*
* The base inode is in icache. Check if it has the extent inode
* corresponding to this extent mft record attached.
*/
ni = NTFS_I(vi);
mutex_lock(&ni->extent_lock);
if (ni->nr_extents <= 0) {
/*
* The base inode has no attached extent inodes, write this
* extent mft record.
*/
mutex_unlock(&ni->extent_lock);
iput(vi);
ntfs_debug("Base inode 0x%lx has no attached extent inodes, "
"write the extent record.", na.mft_no);
return true;
}
/* Iterate over the attached extent inodes. */
extent_nis = ni->ext.extent_ntfs_inos;
for (eni = NULL, i = 0; i < ni->nr_extents; ++i) {
if (mft_no == extent_nis[i]->mft_no) {
/*
* Found the extent inode corresponding to this extent
* mft record.
*/
eni = extent_nis[i];
break;
}
}
/*
* If the extent inode was not attached to the base inode, write this
* extent mft record.
*/
if (!eni) {
mutex_unlock(&ni->extent_lock);
iput(vi);
ntfs_debug("Extent inode 0x%lx is not attached to its base "
"inode 0x%lx, write the extent record.",
mft_no, na.mft_no);
return true;
}
ntfs_debug("Extent inode 0x%lx is attached to its base inode 0x%lx.",
mft_no, na.mft_no);
/* Take a reference to the extent ntfs inode. */
atomic_inc(&eni->count);
mutex_unlock(&ni->extent_lock);
/*
* Found the extent inode coresponding to this extent mft record.
* Try to take the mft record lock.
*/
if (unlikely(!mutex_trylock(&eni->mrec_lock))) {
atomic_dec(&eni->count);
iput(vi);
ntfs_debug("Extent mft record 0x%lx is already locked, do "
"not write it.", mft_no);
return false;
}
ntfs_debug("Managed to lock extent mft record 0x%lx, write it.",
mft_no);
if (NInoTestClearDirty(eni))
ntfs_debug("Extent inode 0x%lx is dirty, marking it clean.",
mft_no);
/*
* The write has to occur while we hold the mft record lock so return
* the locked extent ntfs inode.
*/
*locked_ni = eni;
return true;
}
static const char *es = " Leaving inconsistent metadata. Unmount and run "
"chkdsk.";
/**
* ntfs_mft_bitmap_find_and_alloc_free_rec_nolock - see name
* @vol: volume on which to search for a free mft record
* @base_ni: open base inode if allocating an extent mft record or NULL
*
* Search for a free mft record in the mft bitmap attribute on the ntfs volume
* @vol.
*
* If @base_ni is NULL start the search at the default allocator position.
*
* If @base_ni is not NULL start the search at the mft record after the base
* mft record @base_ni.
*
* Return the free mft record on success and -errno on error. An error code of
* -ENOSPC means that there are no free mft records in the currently
* initialized mft bitmap.
*
* Locking: Caller must hold vol->mftbmp_lock for writing.
*/
static int ntfs_mft_bitmap_find_and_alloc_free_rec_nolock(ntfs_volume *vol,
ntfs_inode *base_ni)
{
s64 pass_end, ll, data_pos, pass_start, ofs, bit;
unsigned long flags;
struct address_space *mftbmp_mapping;
u8 *buf, *byte;
struct page *page;
unsigned int page_ofs, size;
u8 pass, b;
ntfs_debug("Searching for free mft record in the currently "
"initialized mft bitmap.");
mftbmp_mapping = vol->mftbmp_ino->i_mapping;
/*
* Set the end of the pass making sure we do not overflow the mft
* bitmap.
*/
read_lock_irqsave(&NTFS_I(vol->mft_ino)->size_lock, flags);
pass_end = NTFS_I(vol->mft_ino)->allocated_size >>
vol->mft_record_size_bits;
read_unlock_irqrestore(&NTFS_I(vol->mft_ino)->size_lock, flags);
read_lock_irqsave(&NTFS_I(vol->mftbmp_ino)->size_lock, flags);
ll = NTFS_I(vol->mftbmp_ino)->initialized_size << 3;
read_unlock_irqrestore(&NTFS_I(vol->mftbmp_ino)->size_lock, flags);
if (pass_end > ll)
pass_end = ll;
pass = 1;
if (!base_ni)
data_pos = vol->mft_data_pos;
else
data_pos = base_ni->mft_no + 1;
if (data_pos < 24)
data_pos = 24;
if (data_pos >= pass_end) {
data_pos = 24;
pass = 2;
/* This happens on a freshly formatted volume. */
if (data_pos >= pass_end)
return -ENOSPC;
}
pass_start = data_pos;
ntfs_debug("Starting bitmap search: pass %u, pass_start 0x%llx, "
"pass_end 0x%llx, data_pos 0x%llx.", pass,
(long long)pass_start, (long long)pass_end,
(long long)data_pos);
/* Loop until a free mft record is found. */
for (; pass <= 2;) {
/* Cap size to pass_end. */
ofs = data_pos >> 3;
page_ofs = ofs & ~PAGE_MASK;
size = PAGE_SIZE - page_ofs;
ll = ((pass_end + 7) >> 3) - ofs;
if (size > ll)
size = ll;
size <<= 3;
/*
* If we are still within the active pass, search the next page
* for a zero bit.
*/
if (size) {
page = ntfs_map_page(mftbmp_mapping,
ofs >> PAGE_SHIFT);
if (IS_ERR(page)) {
ntfs_error(vol->sb, "Failed to read mft "
"bitmap, aborting.");
return PTR_ERR(page);
}
buf = (u8*)page_address(page) + page_ofs;
bit = data_pos & 7;
data_pos &= ~7ull;
ntfs_debug("Before inner for loop: size 0x%x, "
"data_pos 0x%llx, bit 0x%llx", size,
(long long)data_pos, (long long)bit);
for (; bit < size && data_pos + bit < pass_end;
bit &= ~7ull, bit += 8) {
byte = buf + (bit >> 3);
if (*byte == 0xff)
continue;
b = ffz((unsigned long)*byte);
if (b < 8 && b >= (bit & 7)) {
ll = data_pos + (bit & ~7ull) + b;
if (unlikely(ll > (1ll << 32))) {
ntfs_unmap_page(page);
return -ENOSPC;
}
*byte |= 1 << b;
flush_dcache_page(page);
set_page_dirty(page);
ntfs_unmap_page(page);
ntfs_debug("Done. (Found and "
"allocated mft record "
"0x%llx.)",
(long long)ll);
return ll;
}
}
ntfs_debug("After inner for loop: size 0x%x, "
"data_pos 0x%llx, bit 0x%llx", size,
(long long)data_pos, (long long)bit);
data_pos += size;
ntfs_unmap_page(page);
/*
* If the end of the pass has not been reached yet,
* continue searching the mft bitmap for a zero bit.
*/
if (data_pos < pass_end)
continue;
}
/* Do the next pass. */
if (++pass == 2) {
/*
* Starting the second pass, in which we scan the first
* part of the zone which we omitted earlier.
*/
pass_end = pass_start;
data_pos = pass_start = 24;
ntfs_debug("pass %i, pass_start 0x%llx, pass_end "
"0x%llx.", pass, (long long)pass_start,
(long long)pass_end);
if (data_pos >= pass_end)
break;
}
}
/* No free mft records in currently initialized mft bitmap. */
ntfs_debug("Done. (No free mft records left in currently initialized "
"mft bitmap.)");
return -ENOSPC;
}
/**
* ntfs_mft_bitmap_extend_allocation_nolock - extend mft bitmap by a cluster
* @vol: volume on which to extend the mft bitmap attribute
*
* Extend the mft bitmap attribute on the ntfs volume @vol by one cluster.
*
* Note: Only changes allocated_size, i.e. does not touch initialized_size or
* data_size.
*
* Return 0 on success and -errno on error.
*
* Locking: - Caller must hold vol->mftbmp_lock for writing.
* - This function takes NTFS_I(vol->mftbmp_ino)->runlist.lock for
* writing and releases it before returning.
* - This function takes vol->lcnbmp_lock for writing and releases it
* before returning.
*/
static int ntfs_mft_bitmap_extend_allocation_nolock(ntfs_volume *vol)
{
LCN lcn;
s64 ll;
unsigned long flags;
struct page *page;
ntfs_inode *mft_ni, *mftbmp_ni;
runlist_element *rl, *rl2 = NULL;
ntfs_attr_search_ctx *ctx = NULL;
MFT_RECORD *mrec;
ATTR_RECORD *a = NULL;
int ret, mp_size;
u32 old_alen = 0;
u8 *b, tb;
struct {
u8 added_cluster:1;
u8 added_run:1;
u8 mp_rebuilt:1;
} status = { 0, 0, 0 };
ntfs_debug("Extending mft bitmap allocation.");
mft_ni = NTFS_I(vol->mft_ino);
mftbmp_ni = NTFS_I(vol->mftbmp_ino);
/*
* Determine the last lcn of the mft bitmap. The allocated size of the
* mft bitmap cannot be zero so we are ok to do this.
*/
down_write(&mftbmp_ni->runlist.lock);
read_lock_irqsave(&mftbmp_ni->size_lock, flags);
ll = mftbmp_ni->allocated_size;
read_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
rl = ntfs_attr_find_vcn_nolock(mftbmp_ni,
(ll - 1) >> vol->cluster_size_bits, NULL);
if (unlikely(IS_ERR(rl) || !rl->length || rl->lcn < 0)) {
up_write(&mftbmp_ni->runlist.lock);
ntfs_error(vol->sb, "Failed to determine last allocated "
"cluster of mft bitmap attribute.");
if (!IS_ERR(rl))
ret = -EIO;
else
ret = PTR_ERR(rl);
return ret;
}
lcn = rl->lcn + rl->length;
ntfs_debug("Last lcn of mft bitmap attribute is 0x%llx.",
(long long)lcn);
/*
* Attempt to get the cluster following the last allocated cluster by
* hand as it may be in the MFT zone so the allocator would not give it
* to us.
*/
ll = lcn >> 3;
page = ntfs_map_page(vol->lcnbmp_ino->i_mapping,
ll >> PAGE_SHIFT);
if (IS_ERR(page)) {
up_write(&mftbmp_ni->runlist.lock);
ntfs_error(vol->sb, "Failed to read from lcn bitmap.");
return PTR_ERR(page);
}
b = (u8*)page_address(page) + (ll & ~PAGE_MASK);
tb = 1 << (lcn & 7ull);
down_write(&vol->lcnbmp_lock);
if (*b != 0xff && !(*b & tb)) {
/* Next cluster is free, allocate it. */
*b |= tb;
flush_dcache_page(page);
set_page_dirty(page);
up_write(&vol->lcnbmp_lock);
ntfs_unmap_page(page);
/* Update the mft bitmap runlist. */
rl->length++;
rl[1].vcn++;
status.added_cluster = 1;
ntfs_debug("Appending one cluster to mft bitmap.");
} else {
up_write(&vol->lcnbmp_lock);
ntfs_unmap_page(page);
/* Allocate a cluster from the DATA_ZONE. */
rl2 = ntfs_cluster_alloc(vol, rl[1].vcn, 1, lcn, DATA_ZONE,
true);
if (IS_ERR(rl2)) {
up_write(&mftbmp_ni->runlist.lock);
ntfs_error(vol->sb, "Failed to allocate a cluster for "
"the mft bitmap.");
return PTR_ERR(rl2);
}
rl = ntfs_runlists_merge(mftbmp_ni->runlist.rl, rl2);
if (IS_ERR(rl)) {
up_write(&mftbmp_ni->runlist.lock);
ntfs_error(vol->sb, "Failed to merge runlists for mft "
"bitmap.");
if (ntfs_cluster_free_from_rl(vol, rl2)) {
ntfs_error(vol->sb, "Failed to deallocate "
"allocated cluster.%s", es);
NVolSetErrors(vol);
}
ntfs_free(rl2);
return PTR_ERR(rl);
}
mftbmp_ni->runlist.rl = rl;
status.added_run = 1;
ntfs_debug("Adding one run to mft bitmap.");
/* Find the last run in the new runlist. */
for (; rl[1].length; rl++)
;
}
/*
* Update the attribute record as well. Note: @rl is the last
* (non-terminator) runlist element of mft bitmap.
*/
mrec = map_mft_record(mft_ni);
if (IS_ERR(mrec)) {
ntfs_error(vol->sb, "Failed to map mft record.");
ret = PTR_ERR(mrec);
goto undo_alloc;
}
ctx = ntfs_attr_get_search_ctx(mft_ni, mrec);
if (unlikely(!ctx)) {
ntfs_error(vol->sb, "Failed to get search context.");
ret = -ENOMEM;
goto undo_alloc;
}
ret = ntfs_attr_lookup(mftbmp_ni->type, mftbmp_ni->name,
mftbmp_ni->name_len, CASE_SENSITIVE, rl[1].vcn, NULL,
0, ctx);
if (unlikely(ret)) {
ntfs_error(vol->sb, "Failed to find last attribute extent of "
"mft bitmap attribute.");
if (ret == -ENOENT)
ret = -EIO;
goto undo_alloc;
}
a = ctx->attr;
ll = sle64_to_cpu(a->data.non_resident.lowest_vcn);
/* Search back for the previous last allocated cluster of mft bitmap. */
for (rl2 = rl; rl2 > mftbmp_ni->runlist.rl; rl2--) {
if (ll >= rl2->vcn)
break;
}
BUG_ON(ll < rl2->vcn);
BUG_ON(ll >= rl2->vcn + rl2->length);
/* Get the size for the new mapping pairs array for this extent. */
mp_size = ntfs_get_size_for_mapping_pairs(vol, rl2, ll, -1);
if (unlikely(mp_size <= 0)) {
ntfs_error(vol->sb, "Get size for mapping pairs failed for "
"mft bitmap attribute extent.");
ret = mp_size;
if (!ret)
ret = -EIO;
goto undo_alloc;
}
/* Expand the attribute record if necessary. */
old_alen = le32_to_cpu(a->length);
ret = ntfs_attr_record_resize(ctx->mrec, a, mp_size +
le16_to_cpu(a->data.non_resident.mapping_pairs_offset));
if (unlikely(ret)) {
if (ret != -ENOSPC) {
ntfs_error(vol->sb, "Failed to resize attribute "
"record for mft bitmap attribute.");
goto undo_alloc;
}
// TODO: Deal with this by moving this extent to a new mft
// record or by starting a new extent in a new mft record or by
// moving other attributes out of this mft record.
// Note: It will need to be a special mft record and if none of
// those are available it gets rather complicated...
ntfs_error(vol->sb, "Not enough space in this mft record to "
"accommodate extended mft bitmap attribute "
"extent. Cannot handle this yet.");
ret = -EOPNOTSUPP;
goto undo_alloc;
}
status.mp_rebuilt = 1;
/* Generate the mapping pairs array directly into the attr record. */
ret = ntfs_mapping_pairs_build(vol, (u8*)a +
le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
mp_size, rl2, ll, -1, NULL);
if (unlikely(ret)) {
ntfs_error(vol->sb, "Failed to build mapping pairs array for "
"mft bitmap attribute.");
goto undo_alloc;
}
/* Update the highest_vcn. */
a->data.non_resident.highest_vcn = cpu_to_sle64(rl[1].vcn - 1);
/*
* We now have extended the mft bitmap allocated_size by one cluster.
* Reflect this in the ntfs_inode structure and the attribute record.
*/
if (a->data.non_resident.lowest_vcn) {
/*
* We are not in the first attribute extent, switch to it, but
* first ensure the changes will make it to disk later.
*/
flush_dcache_mft_record_page(ctx->ntfs_ino);
mark_mft_record_dirty(ctx->ntfs_ino);
ntfs_attr_reinit_search_ctx(ctx);
ret = ntfs_attr_lookup(mftbmp_ni->type, mftbmp_ni->name,
mftbmp_ni->name_len, CASE_SENSITIVE, 0, NULL,
0, ctx);
if (unlikely(ret)) {
ntfs_error(vol->sb, "Failed to find first attribute "
"extent of mft bitmap attribute.");
goto restore_undo_alloc;
}
a = ctx->attr;
}
write_lock_irqsave(&mftbmp_ni->size_lock, flags);
mftbmp_ni->allocated_size += vol->cluster_size;
a->data.non_resident.allocated_size =
cpu_to_sle64(mftbmp_ni->allocated_size);
write_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
/* Ensure the changes make it to disk. */
flush_dcache_mft_record_page(ctx->ntfs_ino);
mark_mft_record_dirty(ctx->ntfs_ino);
ntfs_attr_put_search_ctx(ctx);
unmap_mft_record(mft_ni);
up_write(&mftbmp_ni->runlist.lock);
ntfs_debug("Done.");
return 0;
restore_undo_alloc:
ntfs_attr_reinit_search_ctx(ctx);
if (ntfs_attr_lookup(mftbmp_ni->type, mftbmp_ni->name,
mftbmp_ni->name_len, CASE_SENSITIVE, rl[1].vcn, NULL,
0, ctx)) {
ntfs_error(vol->sb, "Failed to find last attribute extent of "
"mft bitmap attribute.%s", es);
write_lock_irqsave(&mftbmp_ni->size_lock, flags);
mftbmp_ni->allocated_size += vol->cluster_size;
write_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
ntfs_attr_put_search_ctx(ctx);
unmap_mft_record(mft_ni);
up_write(&mftbmp_ni->runlist.lock);
/*
* The only thing that is now wrong is ->allocated_size of the
* base attribute extent which chkdsk should be able to fix.
*/
NVolSetErrors(vol);
return ret;
}
a = ctx->attr;
a->data.non_resident.highest_vcn = cpu_to_sle64(rl[1].vcn - 2);
undo_alloc:
if (status.added_cluster) {
/* Truncate the last run in the runlist by one cluster. */
rl->length--;
rl[1].vcn--;
} else if (status.added_run) {
lcn = rl->lcn;
/* Remove the last run from the runlist. */
rl->lcn = rl[1].lcn;
rl->length = 0;
}
/* Deallocate the cluster. */
down_write(&vol->lcnbmp_lock);
if (ntfs_bitmap_clear_bit(vol->lcnbmp_ino, lcn)) {
ntfs_error(vol->sb, "Failed to free allocated cluster.%s", es);
NVolSetErrors(vol);
}
up_write(&vol->lcnbmp_lock);
if (status.mp_rebuilt) {
if (ntfs_mapping_pairs_build(vol, (u8*)a + le16_to_cpu(
a->data.non_resident.mapping_pairs_offset),
old_alen - le16_to_cpu(
a->data.non_resident.mapping_pairs_offset),
rl2, ll, -1, NULL)) {
ntfs_error(vol->sb, "Failed to restore mapping pairs "
"array.%s", es);
NVolSetErrors(vol);
}
if (ntfs_attr_record_resize(ctx->mrec, a, old_alen)) {
ntfs_error(vol->sb, "Failed to restore attribute "
"record.%s", es);
NVolSetErrors(vol);
}
flush_dcache_mft_record_page(ctx->ntfs_ino);
mark_mft_record_dirty(ctx->ntfs_ino);
}
if (ctx)
ntfs_attr_put_search_ctx(ctx);
if (!IS_ERR(mrec))
unmap_mft_record(mft_ni);
up_write(&mftbmp_ni->runlist.lock);
return ret;
}
/**
* ntfs_mft_bitmap_extend_initialized_nolock - extend mftbmp initialized data
* @vol: volume on which to extend the mft bitmap attribute
*
* Extend the initialized portion of the mft bitmap attribute on the ntfs
* volume @vol by 8 bytes.
*
* Note: Only changes initialized_size and data_size, i.e. requires that
* allocated_size is big enough to fit the new initialized_size.
*
* Return 0 on success and -error on error.
*
* Locking: Caller must hold vol->mftbmp_lock for writing.
*/
static int ntfs_mft_bitmap_extend_initialized_nolock(ntfs_volume *vol)
{
s64 old_data_size, old_initialized_size;
unsigned long flags;
struct inode *mftbmp_vi;
ntfs_inode *mft_ni, *mftbmp_ni;
ntfs_attr_search_ctx *ctx;
MFT_RECORD *mrec;
ATTR_RECORD *a;
int ret;
ntfs_debug("Extending mft bitmap initiailized (and data) size.");
mft_ni = NTFS_I(vol->mft_ino);
mftbmp_vi = vol->mftbmp_ino;
mftbmp_ni = NTFS_I(mftbmp_vi);
/* Get the attribute record. */
mrec = map_mft_record(mft_ni);
if (IS_ERR(mrec)) {
ntfs_error(vol->sb, "Failed to map mft record.");
return PTR_ERR(mrec);
}
ctx = ntfs_attr_get_search_ctx(mft_ni, mrec);
if (unlikely(!ctx)) {
ntfs_error(vol->sb, "Failed to get search context.");
ret = -ENOMEM;
goto unm_err_out;
}
ret = ntfs_attr_lookup(mftbmp_ni->type, mftbmp_ni->name,
mftbmp_ni->name_len, CASE_SENSITIVE, 0, NULL, 0, ctx);
if (unlikely(ret)) {
ntfs_error(vol->sb, "Failed to find first attribute extent of "
"mft bitmap attribute.");
if (ret == -ENOENT)
ret = -EIO;
goto put_err_out;
}
a = ctx->attr;
write_lock_irqsave(&mftbmp_ni->size_lock, flags);
old_data_size = i_size_read(mftbmp_vi);
old_initialized_size = mftbmp_ni->initialized_size;
/*
* We can simply update the initialized_size before filling the space
* with zeroes because the caller is holding the mft bitmap lock for
* writing which ensures that no one else is trying to access the data.
*/
mftbmp_ni->initialized_size += 8;
a->data.non_resident.initialized_size =
cpu_to_sle64(mftbmp_ni->initialized_size);
if (mftbmp_ni->initialized_size > old_data_size) {
i_size_write(mftbmp_vi, mftbmp_ni->initialized_size);
a->data.non_resident.data_size =
cpu_to_sle64(mftbmp_ni->initialized_size);
}
write_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
/* Ensure the changes make it to disk. */
flush_dcache_mft_record_page(ctx->ntfs_ino);
mark_mft_record_dirty(ctx->ntfs_ino);
ntfs_attr_put_search_ctx(ctx);
unmap_mft_record(mft_ni);
/* Initialize the mft bitmap attribute value with zeroes. */
ret = ntfs_attr_set(mftbmp_ni, old_initialized_size, 8, 0);
if (likely(!ret)) {
ntfs_debug("Done. (Wrote eight initialized bytes to mft "
"bitmap.");
return 0;
}
ntfs_error(vol->sb, "Failed to write to mft bitmap.");
/* Try to recover from the error. */
mrec = map_mft_record(mft_ni);
if (IS_ERR(mrec)) {
ntfs_error(vol->sb, "Failed to map mft record.%s", es);
NVolSetErrors(vol);
return ret;
}
ctx = ntfs_attr_get_search_ctx(mft_ni, mrec);
if (unlikely(!ctx)) {
ntfs_error(vol->sb, "Failed to get search context.%s", es);
NVolSetErrors(vol);
goto unm_err_out;
}
if (ntfs_attr_lookup(mftbmp_ni->type, mftbmp_ni->name,
mftbmp_ni->name_len, CASE_SENSITIVE, 0, NULL, 0, ctx)) {
ntfs_error(vol->sb, "Failed to find first attribute extent of "
"mft bitmap attribute.%s", es);
NVolSetErrors(vol);
put_err_out:
ntfs_attr_put_search_ctx(ctx);
unm_err_out:
unmap_mft_record(mft_ni);
goto err_out;
}
a = ctx->attr;
write_lock_irqsave(&mftbmp_ni->size_lock, flags);
mftbmp_ni->initialized_size = old_initialized_size;
a->data.non_resident.initialized_size =
cpu_to_sle64(old_initialized_size);
if (i_size_read(mftbmp_vi) != old_data_size) {
i_size_write(mftbmp_vi, old_data_size);
a->data.non_resident.data_size = cpu_to_sle64(old_data_size);
}
write_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
flush_dcache_mft_record_page(ctx->ntfs_ino);
mark_mft_record_dirty(ctx->ntfs_ino);
ntfs_attr_put_search_ctx(ctx);
unmap_mft_record(mft_ni);
#ifdef DEBUG
read_lock_irqsave(&mftbmp_ni->size_lock, flags);
ntfs_debug("Restored status of mftbmp: allocated_size 0x%llx, "
"data_size 0x%llx, initialized_size 0x%llx.",
(long long)mftbmp_ni->allocated_size,
(long long)i_size_read(mftbmp_vi),
(long long)mftbmp_ni->initialized_size);
read_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
#endif /* DEBUG */
err_out:
return ret;
}
/**
* ntfs_mft_data_extend_allocation_nolock - extend mft data attribute
* @vol: volume on which to extend the mft data attribute
*
* Extend the mft data attribute on the ntfs volume @vol by 16 mft records
* worth of clusters or if not enough space for this by one mft record worth
* of clusters.
*
* Note: Only changes allocated_size, i.e. does not touch initialized_size or
* data_size.
*
* Return 0 on success and -errno on error.
*
* Locking: - Caller must hold vol->mftbmp_lock for writing.
* - This function takes NTFS_I(vol->mft_ino)->runlist.lock for
* writing and releases it before returning.
* - This function calls functions which take vol->lcnbmp_lock for
* writing and release it before returning.
*/
static int ntfs_mft_data_extend_allocation_nolock(ntfs_volume *vol)
{
LCN lcn;
VCN old_last_vcn;
s64 min_nr, nr, ll;
unsigned long flags;
ntfs_inode *mft_ni;
runlist_element *rl, *rl2;
ntfs_attr_search_ctx *ctx = NULL;
MFT_RECORD *mrec;
ATTR_RECORD *a = NULL;
int ret, mp_size;
u32 old_alen = 0;
bool mp_rebuilt = false;
ntfs_debug("Extending mft data allocation.");
mft_ni = NTFS_I(vol->mft_ino);
/*
* Determine the preferred allocation location, i.e. the last lcn of
* the mft data attribute. The allocated size of the mft data
* attribute cannot be zero so we are ok to do this.
*/
down_write(&mft_ni->runlist.lock);
read_lock_irqsave(&mft_ni->size_lock, flags);
ll = mft_ni->allocated_size;
read_unlock_irqrestore(&mft_ni->size_lock, flags);
rl = ntfs_attr_find_vcn_nolock(mft_ni,
(ll - 1) >> vol->cluster_size_bits, NULL);
if (unlikely(IS_ERR(rl) || !rl->length || rl->lcn < 0)) {
up_write(&mft_ni->runlist.lock);
ntfs_error(vol->sb, "Failed to determine last allocated "
"cluster of mft data attribute.");
if (!IS_ERR(rl))
ret = -EIO;
else
ret = PTR_ERR(rl);
return ret;
}
lcn = rl->lcn + rl->length;
ntfs_debug("Last lcn of mft data attribute is 0x%llx.", (long long)lcn);
/* Minimum allocation is one mft record worth of clusters. */
min_nr = vol->mft_record_size >> vol->cluster_size_bits;
if (!min_nr)
min_nr = 1;
/* Want to allocate 16 mft records worth of clusters. */
nr = vol->mft_record_size << 4 >> vol->cluster_size_bits;
if (!nr)
nr = min_nr;
/* Ensure we do not go above 2^32-1 mft records. */
read_lock_irqsave(&mft_ni->size_lock, flags);
ll = mft_ni->allocated_size;
read_unlock_irqrestore(&mft_ni->size_lock, flags);
if (unlikely((ll + (nr << vol->cluster_size_bits)) >>
vol->mft_record_size_bits >= (1ll << 32))) {
nr = min_nr;
if (unlikely((ll + (nr << vol->cluster_size_bits)) >>
vol->mft_record_size_bits >= (1ll << 32))) {
ntfs_warning(vol->sb, "Cannot allocate mft record "
"because the maximum number of inodes "
"(2^32) has already been reached.");
up_write(&mft_ni->runlist.lock);
return -ENOSPC;
}
}
ntfs_debug("Trying mft data allocation with %s cluster count %lli.",
nr > min_nr ? "default" : "minimal", (long long)nr);
old_last_vcn = rl[1].vcn;
do {
rl2 = ntfs_cluster_alloc(vol, old_last_vcn, nr, lcn, MFT_ZONE,
true);
if (likely(!IS_ERR(rl2)))
break;
if (PTR_ERR(rl2) != -ENOSPC || nr == min_nr) {
ntfs_error(vol->sb, "Failed to allocate the minimal "
"number of clusters (%lli) for the "
"mft data attribute.", (long long)nr);
up_write(&mft_ni->runlist.lock);
return PTR_ERR(rl2);
}
/*
* There is not enough space to do the allocation, but there
* might be enough space to do a minimal allocation so try that
* before failing.
*/
nr = min_nr;
ntfs_debug("Retrying mft data allocation with minimal cluster "
"count %lli.", (long long)nr);
} while (1);
rl = ntfs_runlists_merge(mft_ni->runlist.rl, rl2);
if (IS_ERR(rl)) {
up_write(&mft_ni->runlist.lock);
ntfs_error(vol->sb, "Failed to merge runlists for mft data "
"attribute.");
if (ntfs_cluster_free_from_rl(vol, rl2)) {
ntfs_error(vol->sb, "Failed to deallocate clusters "
"from the mft data attribute.%s", es);
NVolSetErrors(vol);
}
ntfs_free(rl2);
return PTR_ERR(rl);
}
mft_ni->runlist.rl = rl;
ntfs_debug("Allocated %lli clusters.", (long long)nr);
/* Find the last run in the new runlist. */
for (; rl[1].length; rl++)
;
/* Update the attribute record as well. */
mrec = map_mft_record(mft_ni);
if (IS_ERR(mrec)) {
ntfs_error(vol->sb, "Failed to map mft record.");
ret = PTR_ERR(mrec);
goto undo_alloc;
}
ctx = ntfs_attr_get_search_ctx(mft_ni, mrec);
if (unlikely(!ctx)) {
ntfs_error(vol->sb, "Failed to get search context.");
ret = -ENOMEM;
goto undo_alloc;
}
ret = ntfs_attr_lookup(mft_ni->type, mft_ni->name, mft_ni->name_len,
CASE_SENSITIVE, rl[1].vcn, NULL, 0, ctx);
if (unlikely(ret)) {
ntfs_error(vol->sb, "Failed to find last attribute extent of "
"mft data attribute.");
if (ret == -ENOENT)
ret = -EIO;
goto undo_alloc;
}
a = ctx->attr;
ll = sle64_to_cpu(a->data.non_resident.lowest_vcn);
/* Search back for the previous last allocated cluster of mft bitmap. */
for (rl2 = rl; rl2 > mft_ni->runlist.rl; rl2--) {
if (ll >= rl2->vcn)
break;
}
BUG_ON(ll < rl2->vcn);
BUG_ON(ll >= rl2->vcn + rl2->length);
/* Get the size for the new mapping pairs array for this extent. */
mp_size = ntfs_get_size_for_mapping_pairs(vol, rl2, ll, -1);
if (unlikely(mp_size <= 0)) {
ntfs_error(vol->sb, "Get size for mapping pairs failed for "
"mft data attribute extent.");
ret = mp_size;
if (!ret)
ret = -EIO;
goto undo_alloc;
}
/* Expand the attribute record if necessary. */
old_alen = le32_to_cpu(a->length);
ret = ntfs_attr_record_resize(ctx->mrec, a, mp_size +
le16_to_cpu(a->data.non_resident.mapping_pairs_offset));
if (unlikely(ret)) {
if (ret != -ENOSPC) {
ntfs_error(vol->sb, "Failed to resize attribute "
"record for mft data attribute.");
goto undo_alloc;
}
// TODO: Deal with this by moving this extent to a new mft
// record or by starting a new extent in a new mft record or by
// moving other attributes out of this mft record.
// Note: Use the special reserved mft records and ensure that
// this extent is not required to find the mft record in
// question. If no free special records left we would need to
// move an existing record away, insert ours in its place, and
// then place the moved record into the newly allocated space
// and we would then need to update all references to this mft
// record appropriately. This is rather complicated...
ntfs_error(vol->sb, "Not enough space in this mft record to "
"accommodate extended mft data attribute "
"extent. Cannot handle this yet.");
ret = -EOPNOTSUPP;
goto undo_alloc;
}
mp_rebuilt = true;
/* Generate the mapping pairs array directly into the attr record. */
ret = ntfs_mapping_pairs_build(vol, (u8*)a +
le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
mp_size, rl2, ll, -1, NULL);
if (unlikely(ret)) {
ntfs_error(vol->sb, "Failed to build mapping pairs array of "
"mft data attribute.");
goto undo_alloc;
}
/* Update the highest_vcn. */
a->data.non_resident.highest_vcn = cpu_to_sle64(rl[1].vcn - 1);
/*
* We now have extended the mft data allocated_size by nr clusters.
* Reflect this in the ntfs_inode structure and the attribute record.
* @rl is the last (non-terminator) runlist element of mft data
* attribute.
*/
if (a->data.non_resident.lowest_vcn) {
/*
* We are not in the first attribute extent, switch to it, but
* first ensure the changes will make it to disk later.
*/
flush_dcache_mft_record_page(ctx->ntfs_ino);
mark_mft_record_dirty(ctx->ntfs_ino);
ntfs_attr_reinit_search_ctx(ctx);
ret = ntfs_attr_lookup(mft_ni->type, mft_ni->name,
mft_ni->name_len, CASE_SENSITIVE, 0, NULL, 0,
ctx);
if (unlikely(ret)) {
ntfs_error(vol->sb, "Failed to find first attribute "
"extent of mft data attribute.");
goto restore_undo_alloc;
}
a = ctx->attr;
}
write_lock_irqsave(&mft_ni->size_lock, flags);
mft_ni->allocated_size += nr << vol->cluster_size_bits;
a->data.non_resident.allocated_size =
cpu_to_sle64(mft_ni->allocated_size);
write_unlock_irqrestore(&mft_ni->size_lock, flags);
/* Ensure the changes make it to disk. */
flush_dcache_mft_record_page(ctx->ntfs_ino);
mark_mft_record_dirty(ctx->ntfs_ino);
ntfs_attr_put_search_ctx(ctx);
unmap_mft_record(mft_ni);
up_write(&mft_ni->runlist.lock);
ntfs_debug("Done.");
return 0;
restore_undo_alloc:
ntfs_attr_reinit_search_ctx(ctx);
if (ntfs_attr_lookup(mft_ni->type, mft_ni->name, mft_ni->name_len,
CASE_SENSITIVE, rl[1].vcn, NULL, 0, ctx)) {
ntfs_error(vol->sb, "Failed to find last attribute extent of "
"mft data attribute.%s", es);
write_lock_irqsave(&mft_ni->size_lock, flags);
mft_ni->allocated_size += nr << vol->cluster_size_bits;
write_unlock_irqrestore(&mft_ni->size_lock, flags);
ntfs_attr_put_search_ctx(ctx);
unmap_mft_record(mft_ni);
up_write(&mft_ni->runlist.lock);
/*
* The only thing that is now wrong is ->allocated_size of the
* base attribute extent which chkdsk should be able to fix.
*/
NVolSetErrors(vol);
return ret;
}
ctx->attr->data.non_resident.highest_vcn =
cpu_to_sle64(old_last_vcn - 1);
undo_alloc:
if (ntfs_cluster_free(mft_ni, old_last_vcn, -1, ctx) < 0) {
ntfs_error(vol->sb, "Failed to free clusters from mft data "
"attribute.%s", es);
NVolSetErrors(vol);
}
a = ctx->attr;
if (ntfs_rl_truncate_nolock(vol, &mft_ni->runlist, old_last_vcn)) {
ntfs_error(vol->sb, "Failed to truncate mft data attribute "
"runlist.%s", es);
NVolSetErrors(vol);
}
if (mp_rebuilt && !IS_ERR(ctx->mrec)) {
if (ntfs_mapping_pairs_build(vol, (u8*)a + le16_to_cpu(
a->data.non_resident.mapping_pairs_offset),
old_alen - le16_to_cpu(
a->data.non_resident.mapping_pairs_offset),
rl2, ll, -1, NULL)) {
ntfs_error(vol->sb, "Failed to restore mapping pairs "
"array.%s", es);
NVolSetErrors(vol);
}
if (ntfs_attr_record_resize(ctx->mrec, a, old_alen)) {
ntfs_error(vol->sb, "Failed to restore attribute "
"record.%s", es);
NVolSetErrors(vol);
}
flush_dcache_mft_record_page(ctx->ntfs_ino);
mark_mft_record_dirty(ctx->ntfs_ino);
} else if (IS_ERR(ctx->mrec)) {
ntfs_error(vol->sb, "Failed to restore attribute search "
"context.%s", es);
NVolSetErrors(vol);
}
if (ctx)
ntfs_attr_put_search_ctx(ctx);
if (!IS_ERR(mrec))
unmap_mft_record(mft_ni);
up_write(&mft_ni->runlist.lock);
return ret;
}
/**
* ntfs_mft_record_layout - layout an mft record into a memory buffer
* @vol: volume to which the mft record will belong
* @mft_no: mft reference specifying the mft record number
* @m: destination buffer of size >= @vol->mft_record_size bytes
*
* Layout an empty, unused mft record with the mft record number @mft_no into
* the buffer @m. The volume @vol is needed because the mft record structure
* was modified in NTFS 3.1 so we need to know which volume version this mft
* record will be used on.
*
* Return 0 on success and -errno on error.
*/
static int ntfs_mft_record_layout(const ntfs_volume *vol, const s64 mft_no,
MFT_RECORD *m)
{
ATTR_RECORD *a;
ntfs_debug("Entering for mft record 0x%llx.", (long long)mft_no);
if (mft_no >= (1ll << 32)) {
ntfs_error(vol->sb, "Mft record number 0x%llx exceeds "
"maximum of 2^32.", (long long)mft_no);
return -ERANGE;
}
/* Start by clearing the whole mft record to gives us a clean slate. */
memset(m, 0, vol->mft_record_size);
/* Aligned to 2-byte boundary. */
if (vol->major_ver < 3 || (vol->major_ver == 3 && !vol->minor_ver))
m->usa_ofs = cpu_to_le16((sizeof(MFT_RECORD_OLD) + 1) & ~1);
else {
m->usa_ofs = cpu_to_le16((sizeof(MFT_RECORD) + 1) & ~1);
/*
* Set the NTFS 3.1+ specific fields while we know that the
* volume version is 3.1+.
*/
m->reserved = 0;
m->mft_record_number = cpu_to_le32((u32)mft_no);
}
m->magic = magic_FILE;
if (vol->mft_record_size >= NTFS_BLOCK_SIZE)
m->usa_count = cpu_to_le16(vol->mft_record_size /
NTFS_BLOCK_SIZE + 1);
else {
m->usa_count = cpu_to_le16(1);
ntfs_warning(vol->sb, "Sector size is bigger than mft record "
"size. Setting usa_count to 1. If chkdsk "
"reports this as corruption, please email "
"linux-ntfs-dev@lists.sourceforge.net stating "
"that you saw this message and that the "
"modified filesystem created was corrupt. "
"Thank you.");
}
/* Set the update sequence number to 1. */
*(le16*)((u8*)m + le16_to_cpu(m->usa_ofs)) = cpu_to_le16(1);
m->lsn = 0;
m->sequence_number = cpu_to_le16(1);
m->link_count = 0;
/*
* Place the attributes straight after the update sequence array,
* aligned to 8-byte boundary.
*/
m->attrs_offset = cpu_to_le16((le16_to_cpu(m->usa_ofs) +
(le16_to_cpu(m->usa_count) << 1) + 7) & ~7);
m->flags = 0;
/*
* Using attrs_offset plus eight bytes (for the termination attribute).
* attrs_offset is already aligned to 8-byte boundary, so no need to
* align again.
*/
m->bytes_in_use = cpu_to_le32(le16_to_cpu(m->attrs_offset) + 8);
m->bytes_allocated = cpu_to_le32(vol->mft_record_size);
m->base_mft_record = 0;
m->next_attr_instance = 0;
/* Add the termination attribute. */
a = (ATTR_RECORD*)((u8*)m + le16_to_cpu(m->attrs_offset));
a->type = AT_END;
a->length = 0;
ntfs_debug("Done.");
return 0;
}
/**
* ntfs_mft_record_format - format an mft record on an ntfs volume
* @vol: volume on which to format the mft record
* @mft_no: mft record number to format
*
* Format the mft record @mft_no in $MFT/$DATA, i.e. lay out an empty, unused
* mft record into the appropriate place of the mft data attribute. This is
* used when extending the mft data attribute.
*
* Return 0 on success and -errno on error.
*/
static int ntfs_mft_record_format(const ntfs_volume *vol, const s64 mft_no)
{
loff_t i_size;
struct inode *mft_vi = vol->mft_ino;
struct page *page;
MFT_RECORD *m;
pgoff_t index, end_index;
unsigned int ofs;
int err;
ntfs_debug("Entering for mft record 0x%llx.", (long long)mft_no);
/*
* The index into the page cache and the offset within the page cache
* page of the wanted mft record.
*/
index = mft_no << vol->mft_record_size_bits >> PAGE_SHIFT;
ofs = (mft_no << vol->mft_record_size_bits) & ~PAGE_MASK;
/* The maximum valid index into the page cache for $MFT's data. */
i_size = i_size_read(mft_vi);
end_index = i_size >> PAGE_SHIFT;
if (unlikely(index >= end_index)) {
if (unlikely(index > end_index || ofs + vol->mft_record_size >=
(i_size & ~PAGE_MASK))) {
ntfs_error(vol->sb, "Tried to format non-existing mft "
"record 0x%llx.", (long long)mft_no);
return -ENOENT;
}
}
/* Read, map, and pin the page containing the mft record. */
page = ntfs_map_page(mft_vi->i_mapping, index);
if (IS_ERR(page)) {
ntfs_error(vol->sb, "Failed to map page containing mft record "
"to format 0x%llx.", (long long)mft_no);
return PTR_ERR(page);
}
lock_page(page);
BUG_ON(!PageUptodate(page));
ClearPageUptodate(page);
m = (MFT_RECORD*)((u8*)page_address(page) + ofs);
err = ntfs_mft_record_layout(vol, mft_no, m);
if (unlikely(err)) {
ntfs_error(vol->sb, "Failed to layout mft record 0x%llx.",
(long long)mft_no);
SetPageUptodate(page);
unlock_page(page);
ntfs_unmap_page(page);
return err;
}
flush_dcache_page(page);
SetPageUptodate(page);
unlock_page(page);
/*
* Make sure the mft record is written out to disk. We could use
* ilookup5() to check if an inode is in icache and so on but this is
* unnecessary as ntfs_writepage() will write the dirty record anyway.
*/
mark_ntfs_record_dirty(page, ofs);
ntfs_unmap_page(page);
ntfs_debug("Done.");
return 0;
}
/**
* ntfs_mft_record_alloc - allocate an mft record on an ntfs volume
* @vol: [IN] volume on which to allocate the mft record
* @mode: [IN] mode if want a file or directory, i.e. base inode or 0
* @base_ni: [IN] open base inode if allocating an extent mft record or NULL
* @mrec: [OUT] on successful return this is the mapped mft record
*
* Allocate an mft record in $MFT/$DATA of an open ntfs volume @vol.
*
* If @base_ni is NULL make the mft record a base mft record, i.e. a file or
* direvctory inode, and allocate it at the default allocator position. In
* this case @mode is the file mode as given to us by the caller. We in
* particular use @mode to distinguish whether a file or a directory is being
* created (S_IFDIR(mode) and S_IFREG(mode), respectively).
*
* If @base_ni is not NULL make the allocated mft record an extent record,
* allocate it starting at the mft record after the base mft record and attach
* the allocated and opened ntfs inode to the base inode @base_ni. In this
* case @mode must be 0 as it is meaningless for extent inodes.
*
* You need to check the return value with IS_ERR(). If false, the function
* was successful and the return value is the now opened ntfs inode of the
* allocated mft record. *@mrec is then set to the allocated, mapped, pinned,
* and locked mft record. If IS_ERR() is true, the function failed and the
* error code is obtained from PTR_ERR(return value). *@mrec is undefined in
* this case.
*
* Allocation strategy:
*
* To find a free mft record, we scan the mft bitmap for a zero bit. To
* optimize this we start scanning at the place specified by @base_ni or if
* @base_ni is NULL we start where we last stopped and we perform wrap around
* when we reach the end. Note, we do not try to allocate mft records below
* number 24 because numbers 0 to 15 are the defined system files anyway and 16
* to 24 are special in that they are used for storing extension mft records
* for the $DATA attribute of $MFT. This is required to avoid the possibility
* of creating a runlist with a circular dependency which once written to disk
* can never be read in again. Windows will only use records 16 to 24 for
* normal files if the volume is completely out of space. We never use them
* which means that when the volume is really out of space we cannot create any
* more files while Windows can still create up to 8 small files. We can start
* doing this at some later time, it does not matter much for now.
*
* When scanning the mft bitmap, we only search up to the last allocated mft
* record. If there are no free records left in the range 24 to number of
* allocated mft records, then we extend the $MFT/$DATA attribute in order to
* create free mft records. We extend the allocated size of $MFT/$DATA by 16
* records at a time or one cluster, if cluster size is above 16kiB. If there
* is not sufficient space to do this, we try to extend by a single mft record
* or one cluster, if cluster size is above the mft record size.
*
* No matter how many mft records we allocate, we initialize only the first
* allocated mft record, incrementing mft data size and initialized size
* accordingly, open an ntfs_inode for it and return it to the caller, unless
* there are less than 24 mft records, in which case we allocate and initialize
* mft records until we reach record 24 which we consider as the first free mft
* record for use by normal files.
*
* If during any stage we overflow the initialized data in the mft bitmap, we
* extend the initialized size (and data size) by 8 bytes, allocating another
* cluster if required. The bitmap data size has to be at least equal to the
* number of mft records in the mft, but it can be bigger, in which case the
* superflous bits are padded with zeroes.
*
* Thus, when we return successfully (IS_ERR() is false), we will have:
* - initialized / extended the mft bitmap if necessary,
* - initialized / extended the mft data if necessary,
* - set the bit corresponding to the mft record being allocated in the
* mft bitmap,
* - opened an ntfs_inode for the allocated mft record, and we will have
* - returned the ntfs_inode as well as the allocated mapped, pinned, and
* locked mft record.
*
* On error, the volume will be left in a consistent state and no record will
* be allocated. If rolling back a partial operation fails, we may leave some
* inconsistent metadata in which case we set NVolErrors() so the volume is
* left dirty when unmounted.
*
* Note, this function cannot make use of most of the normal functions, like
* for example for attribute resizing, etc, because when the run list overflows
* the base mft record and an attribute list is used, it is very important that
* the extension mft records used to store the $DATA attribute of $MFT can be
* reached without having to read the information contained inside them, as
* this would make it impossible to find them in the first place after the
* volume is unmounted. $MFT/$BITMAP probably does not need to follow this
* rule because the bitmap is not essential for finding the mft records, but on
* the other hand, handling the bitmap in this special way would make life
* easier because otherwise there might be circular invocations of functions
* when reading the bitmap.
*/
ntfs_inode *ntfs_mft_record_alloc(ntfs_volume *vol, const int mode,
ntfs_inode *base_ni, MFT_RECORD **mrec)
{
s64 ll, bit, old_data_initialized, old_data_size;
unsigned long flags;
struct inode *vi;
struct page *page;
ntfs_inode *mft_ni, *mftbmp_ni, *ni;
ntfs_attr_search_ctx *ctx;
MFT_RECORD *m;
ATTR_RECORD *a;
pgoff_t index;
unsigned int ofs;
int err;
le16 seq_no, usn;
bool record_formatted = false;
if (base_ni) {
ntfs_debug("Entering (allocating an extent mft record for "
"base mft record 0x%llx).",
(long long)base_ni->mft_no);
/* @mode and @base_ni are mutually exclusive. */
BUG_ON(mode);
} else
ntfs_debug("Entering (allocating a base mft record).");
if (mode) {
/* @mode and @base_ni are mutually exclusive. */
BUG_ON(base_ni);
/* We only support creation of normal files and directories. */
if (!S_ISREG(mode) && !S_ISDIR(mode))
return ERR_PTR(-EOPNOTSUPP);
}
BUG_ON(!mrec);
mft_ni = NTFS_I(vol->mft_ino);
mftbmp_ni = NTFS_I(vol->mftbmp_ino);
down_write(&vol->mftbmp_lock);
bit = ntfs_mft_bitmap_find_and_alloc_free_rec_nolock(vol, base_ni);
if (bit >= 0) {
ntfs_debug("Found and allocated free record (#1), bit 0x%llx.",
(long long)bit);
goto have_alloc_rec;
}
if (bit != -ENOSPC) {
up_write(&vol->mftbmp_lock);
return ERR_PTR(bit);
}
/*
* No free mft records left. If the mft bitmap already covers more
* than the currently used mft records, the next records are all free,
* so we can simply allocate the first unused mft record.
* Note: We also have to make sure that the mft bitmap at least covers
* the first 24 mft records as they are special and whilst they may not
* be in use, we do not allocate from them.
*/
read_lock_irqsave(&mft_ni->size_lock, flags);
ll = mft_ni->initialized_size >> vol->mft_record_size_bits;
read_unlock_irqrestore(&mft_ni->size_lock, flags);
read_lock_irqsave(&mftbmp_ni->size_lock, flags);
old_data_initialized = mftbmp_ni->initialized_size;
read_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
if (old_data_initialized << 3 > ll && old_data_initialized > 3) {
bit = ll;
if (bit < 24)
bit = 24;
if (unlikely(bit >= (1ll << 32)))
goto max_err_out;
ntfs_debug("Found free record (#2), bit 0x%llx.",
(long long)bit);
goto found_free_rec;
}
/*
* The mft bitmap needs to be expanded until it covers the first unused
* mft record that we can allocate.
* Note: The smallest mft record we allocate is mft record 24.
*/
bit = old_data_initialized << 3;
if (unlikely(bit >= (1ll << 32)))
goto max_err_out;
read_lock_irqsave(&mftbmp_ni->size_lock, flags);
old_data_size = mftbmp_ni->allocated_size;
ntfs_debug("Status of mftbmp before extension: allocated_size 0x%llx, "
"data_size 0x%llx, initialized_size 0x%llx.",
(long long)old_data_size,
(long long)i_size_read(vol->mftbmp_ino),
(long long)old_data_initialized);
read_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
if (old_data_initialized + 8 > old_data_size) {
/* Need to extend bitmap by one more cluster. */
ntfs_debug("mftbmp: initialized_size + 8 > allocated_size.");
err = ntfs_mft_bitmap_extend_allocation_nolock(vol);
if (unlikely(err)) {
up_write(&vol->mftbmp_lock);
goto err_out;
}
#ifdef DEBUG
read_lock_irqsave(&mftbmp_ni->size_lock, flags);
ntfs_debug("Status of mftbmp after allocation extension: "
"allocated_size 0x%llx, data_size 0x%llx, "
"initialized_size 0x%llx.",
(long long)mftbmp_ni->allocated_size,
(long long)i_size_read(vol->mftbmp_ino),
(long long)mftbmp_ni->initialized_size);
read_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
#endif /* DEBUG */
}
/*
* We now have sufficient allocated space, extend the initialized_size
* as well as the data_size if necessary and fill the new space with
* zeroes.
*/
err = ntfs_mft_bitmap_extend_initialized_nolock(vol);
if (unlikely(err)) {
up_write(&vol->mftbmp_lock);
goto err_out;
}
#ifdef DEBUG
read_lock_irqsave(&mftbmp_ni->size_lock, flags);
ntfs_debug("Status of mftbmp after initialized extension: "
"allocated_size 0x%llx, data_size 0x%llx, "
"initialized_size 0x%llx.",
(long long)mftbmp_ni->allocated_size,
(long long)i_size_read(vol->mftbmp_ino),
(long long)mftbmp_ni->initialized_size);
read_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
#endif /* DEBUG */
ntfs_debug("Found free record (#3), bit 0x%llx.", (long long)bit);
found_free_rec:
/* @bit is the found free mft record, allocate it in the mft bitmap. */
ntfs_debug("At found_free_rec.");
err = ntfs_bitmap_set_bit(vol->mftbmp_ino, bit);
if (unlikely(err)) {
ntfs_error(vol->sb, "Failed to allocate bit in mft bitmap.");
up_write(&vol->mftbmp_lock);
goto err_out;
}
ntfs_debug("Set bit 0x%llx in mft bitmap.", (long long)bit);
have_alloc_rec:
/*
* The mft bitmap is now uptodate. Deal with mft data attribute now.
* Note, we keep hold of the mft bitmap lock for writing until all
* modifications to the mft data attribute are complete, too, as they
* will impact decisions for mft bitmap and mft record allocation done
* by a parallel allocation and if the lock is not maintained a
* parallel allocation could allocate the same mft record as this one.
*/
ll = (bit + 1) << vol->mft_record_size_bits;
read_lock_irqsave(&mft_ni->size_lock, flags);
old_data_initialized = mft_ni->initialized_size;
read_unlock_irqrestore(&mft_ni->size_lock, flags);
if (ll <= old_data_initialized) {
ntfs_debug("Allocated mft record already initialized.");
goto mft_rec_already_initialized;
}
ntfs_debug("Initializing allocated mft record.");
/*
* The mft record is outside the initialized data. Extend the mft data
* attribute until it covers the allocated record. The loop is only
* actually traversed more than once when a freshly formatted volume is
* first written to so it optimizes away nicely in the common case.
*/
read_lock_irqsave(&mft_ni->size_lock, flags);
ntfs_debug("Status of mft data before extension: "
"allocated_size 0x%llx, data_size 0x%llx, "
"initialized_size 0x%llx.",
(long long)mft_ni->allocated_size,
(long long)i_size_read(vol->mft_ino),
(long long)mft_ni->initialized_size);
while (ll > mft_ni->allocated_size) {
read_unlock_irqrestore(&mft_ni->size_lock, flags);
err = ntfs_mft_data_extend_allocation_nolock(vol);
if (unlikely(err)) {
ntfs_error(vol->sb, "Failed to extend mft data "
"allocation.");
goto undo_mftbmp_alloc_nolock;
}
read_lock_irqsave(&mft_ni->size_lock, flags);
ntfs_debug("Status of mft data after allocation extension: "
"allocated_size 0x%llx, data_size 0x%llx, "
"initialized_size 0x%llx.",
(long long)mft_ni->allocated_size,
(long long)i_size_read(vol->mft_ino),
(long long)mft_ni->initialized_size);
}
read_unlock_irqrestore(&mft_ni->size_lock, flags);
/*
* Extend mft data initialized size (and data size of course) to reach
* the allocated mft record, formatting the mft records allong the way.
* Note: We only modify the ntfs_inode structure as that is all that is
* needed by ntfs_mft_record_format(). We will update the attribute
* record itself in one fell swoop later on.
*/
write_lock_irqsave(&mft_ni->size_lock, flags);
old_data_initialized = mft_ni->initialized_size;
old_data_size = vol->mft_ino->i_size;
while (ll > mft_ni->initialized_size) {
s64 new_initialized_size, mft_no;
new_initialized_size = mft_ni->initialized_size +
vol->mft_record_size;
mft_no = mft_ni->initialized_size >> vol->mft_record_size_bits;
if (new_initialized_size > i_size_read(vol->mft_ino))
i_size_write(vol->mft_ino, new_initialized_size);
write_unlock_irqrestore(&mft_ni->size_lock, flags);
ntfs_debug("Initializing mft record 0x%llx.",
(long long)mft_no);
err = ntfs_mft_record_format(vol, mft_no);
if (unlikely(err)) {
ntfs_error(vol->sb, "Failed to format mft record.");
goto undo_data_init;
}
write_lock_irqsave(&mft_ni->size_lock, flags);
mft_ni->initialized_size = new_initialized_size;
}
write_unlock_irqrestore(&mft_ni->size_lock, flags);
record_formatted = true;
/* Update the mft data attribute record to reflect the new sizes. */
m = map_mft_record(mft_ni);
if (IS_ERR(m)) {
ntfs_error(vol->sb, "Failed to map mft record.");
err = PTR_ERR(m);
goto undo_data_init;
}
ctx = ntfs_attr_get_search_ctx(mft_ni, m);
if (unlikely(!ctx)) {
ntfs_error(vol->sb, "Failed to get search context.");
err = -ENOMEM;
unmap_mft_record(mft_ni);
goto undo_data_init;
}
err = ntfs_attr_lookup(mft_ni->type, mft_ni->name, mft_ni->name_len,
CASE_SENSITIVE, 0, NULL, 0, ctx);
if (unlikely(err)) {
ntfs_error(vol->sb, "Failed to find first attribute extent of "
"mft data attribute.");
ntfs_attr_put_search_ctx(ctx);
unmap_mft_record(mft_ni);
goto undo_data_init;
}
a = ctx->attr;
read_lock_irqsave(&mft_ni->size_lock, flags);
a->data.non_resident.initialized_size =
cpu_to_sle64(mft_ni->initialized_size);
a->data.non_resident.data_size =
cpu_to_sle64(i_size_read(vol->mft_ino));
read_unlock_irqrestore(&mft_ni->size_lock, flags);
/* Ensure the changes make it to disk. */
flush_dcache_mft_record_page(ctx->ntfs_ino);
mark_mft_record_dirty(ctx->ntfs_ino);
ntfs_attr_put_search_ctx(ctx);
unmap_mft_record(mft_ni);
read_lock_irqsave(&mft_ni->size_lock, flags);
ntfs_debug("Status of mft data after mft record initialization: "
"allocated_size 0x%llx, data_size 0x%llx, "
"initialized_size 0x%llx.",
(long long)mft_ni->allocated_size,
(long long)i_size_read(vol->mft_ino),
(long long)mft_ni->initialized_size);
BUG_ON(i_size_read(vol->mft_ino) > mft_ni->allocated_size);
BUG_ON(mft_ni->initialized_size > i_size_read(vol->mft_ino));
read_unlock_irqrestore(&mft_ni->size_lock, flags);
mft_rec_already_initialized:
/*
* We can finally drop the mft bitmap lock as the mft data attribute
* has been fully updated. The only disparity left is that the
* allocated mft record still needs to be marked as in use to match the
* set bit in the mft bitmap but this is actually not a problem since
* this mft record is not referenced from anywhere yet and the fact
* that it is allocated in the mft bitmap means that no-one will try to
* allocate it either.
*/
up_write(&vol->mftbmp_lock);
/*
* We now have allocated and initialized the mft record. Calculate the
* index of and the offset within the page cache page the record is in.
*/
index = bit << vol->mft_record_size_bits >> PAGE_SHIFT;
ofs = (bit << vol->mft_record_size_bits) & ~PAGE_MASK;
/* Read, map, and pin the page containing the mft record. */
page = ntfs_map_page(vol->mft_ino->i_mapping, index);
if (IS_ERR(page)) {
ntfs_error(vol->sb, "Failed to map page containing allocated "
"mft record 0x%llx.", (long long)bit);
err = PTR_ERR(page);
goto undo_mftbmp_alloc;
}
lock_page(page);
BUG_ON(!PageUptodate(page));
ClearPageUptodate(page);
m = (MFT_RECORD*)((u8*)page_address(page) + ofs);
/* If we just formatted the mft record no need to do it again. */
if (!record_formatted) {
/* Sanity check that the mft record is really not in use. */
if (ntfs_is_file_record(m->magic) &&
(m->flags & MFT_RECORD_IN_USE)) {
ntfs_error(vol->sb, "Mft record 0x%llx was marked "
"free in mft bitmap but is marked "
"used itself. Corrupt filesystem. "
"Unmount and run chkdsk.",
(long long)bit);
err = -EIO;
SetPageUptodate(page);
unlock_page(page);
ntfs_unmap_page(page);
NVolSetErrors(vol);
goto undo_mftbmp_alloc;
}
/*
* We need to (re-)format the mft record, preserving the
* sequence number if it is not zero as well as the update
* sequence number if it is not zero or -1 (0xffff). This
* means we do not need to care whether or not something went
* wrong with the previous mft record.
*/
seq_no = m->sequence_number;
usn = *(le16*)((u8*)m + le16_to_cpu(m->usa_ofs));
err = ntfs_mft_record_layout(vol, bit, m);
if (unlikely(err)) {
ntfs_error(vol->sb, "Failed to layout allocated mft "
"record 0x%llx.", (long long)bit);
SetPageUptodate(page);
unlock_page(page);
ntfs_unmap_page(page);
goto undo_mftbmp_alloc;
}
if (seq_no)
m->sequence_number = seq_no;
if (usn && le16_to_cpu(usn) != 0xffff)
*(le16*)((u8*)m + le16_to_cpu(m->usa_ofs)) = usn;
}
/* Set the mft record itself in use. */
m->flags |= MFT_RECORD_IN_USE;
if (S_ISDIR(mode))
m->flags |= MFT_RECORD_IS_DIRECTORY;
flush_dcache_page(page);
SetPageUptodate(page);
if (base_ni) {
MFT_RECORD *m_tmp;
/*
* Setup the base mft record in the extent mft record. This
* completes initialization of the allocated extent mft record
* and we can simply use it with map_extent_mft_record().
*/
m->base_mft_record = MK_LE_MREF(base_ni->mft_no,
base_ni->seq_no);
/*
* Allocate an extent inode structure for the new mft record,
* attach it to the base inode @base_ni and map, pin, and lock
* its, i.e. the allocated, mft record.
*/
m_tmp = map_extent_mft_record(base_ni, bit, &ni);
if (IS_ERR(m_tmp)) {
ntfs_error(vol->sb, "Failed to map allocated extent "
"mft record 0x%llx.", (long long)bit);
err = PTR_ERR(m_tmp);
/* Set the mft record itself not in use. */
m->flags &= cpu_to_le16(
~le16_to_cpu(MFT_RECORD_IN_USE));
flush_dcache_page(page);
/* Make sure the mft record is written out to disk. */
mark_ntfs_record_dirty(page, ofs);
unlock_page(page);
ntfs_unmap_page(page);
goto undo_mftbmp_alloc;
}
BUG_ON(m != m_tmp);
/*
* Make sure the allocated mft record is written out to disk.
* No need to set the inode dirty because the caller is going
* to do that anyway after finishing with the new extent mft
* record (e.g. at a minimum a new attribute will be added to
* the mft record.
*/
mark_ntfs_record_dirty(page, ofs);
unlock_page(page);
/*
* Need to unmap the page since map_extent_mft_record() mapped
* it as well so we have it mapped twice at the moment.
*/
ntfs_unmap_page(page);
} else {
/*
* Allocate a new VFS inode and set it up. NOTE: @vi->i_nlink
* is set to 1 but the mft record->link_count is 0. The caller
* needs to bear this in mind.
*/
vi = new_inode(vol->sb);
if (unlikely(!vi)) {
err = -ENOMEM;
/* Set the mft record itself not in use. */
m->flags &= cpu_to_le16(
~le16_to_cpu(MFT_RECORD_IN_USE));
flush_dcache_page(page);
/* Make sure the mft record is written out to disk. */
mark_ntfs_record_dirty(page, ofs);
unlock_page(page);
ntfs_unmap_page(page);
goto undo_mftbmp_alloc;
}
vi->i_ino = bit;
/*
* This is for checking whether an inode has changed w.r.t. a
* file so that the file can be updated if necessary (compare
* with f_version).
*/
vi->i_version = 1;
/* The owner and group come from the ntfs volume. */
vi->i_uid = vol->uid;
vi->i_gid = vol->gid;
/* Initialize the ntfs specific part of @vi. */
ntfs_init_big_inode(vi);
ni = NTFS_I(vi);
/*
* Set the appropriate mode, attribute type, and name. For
* directories, also setup the index values to the defaults.
*/
if (S_ISDIR(mode)) {
vi->i_mode = S_IFDIR | S_IRWXUGO;
vi->i_mode &= ~vol->dmask;
NInoSetMstProtected(ni);
ni->type = AT_INDEX_ALLOCATION;
ni->name = I30;
ni->name_len = 4;
ni->itype.index.block_size = 4096;
ni->itype.index.block_size_bits = ntfs_ffs(4096) - 1;
ni->itype.index.collation_rule = COLLATION_FILE_NAME;
if (vol->cluster_size <= ni->itype.index.block_size) {
ni->itype.index.vcn_size = vol->cluster_size;
ni->itype.index.vcn_size_bits =
vol->cluster_size_bits;
} else {
ni->itype.index.vcn_size = vol->sector_size;
ni->itype.index.vcn_size_bits =
vol->sector_size_bits;
}
} else {
vi->i_mode = S_IFREG | S_IRWXUGO;
vi->i_mode &= ~vol->fmask;
ni->type = AT_DATA;
ni->name = NULL;
ni->name_len = 0;
}
if (IS_RDONLY(vi))
vi->i_mode &= ~S_IWUGO;
/* Set the inode times to the current time. */
vi->i_atime = vi->i_mtime = vi->i_ctime =
current_fs_time(vi->i_sb);
/*
* Set the file size to 0, the ntfs inode sizes are set to 0 by
* the call to ntfs_init_big_inode() below.
*/
vi->i_size = 0;
vi->i_blocks = 0;
/* Set the sequence number. */
vi->i_generation = ni->seq_no = le16_to_cpu(m->sequence_number);
/*
* Manually map, pin, and lock the mft record as we already
* have its page mapped and it is very easy to do.
*/
atomic_inc(&ni->count);
mutex_lock(&ni->mrec_lock);
ni->page = page;
ni->page_ofs = ofs;
/*
* Make sure the allocated mft record is written out to disk.
* NOTE: We do not set the ntfs inode dirty because this would
* fail in ntfs_write_inode() because the inode does not have a
* standard information attribute yet. Also, there is no need
* to set the inode dirty because the caller is going to do
* that anyway after finishing with the new mft record (e.g. at
* a minimum some new attributes will be added to the mft
* record.
*/
mark_ntfs_record_dirty(page, ofs);
unlock_page(page);
/* Add the inode to the inode hash for the superblock. */
insert_inode_hash(vi);
/* Update the default mft allocation position. */
vol->mft_data_pos = bit + 1;
}
/*
* Return the opened, allocated inode of the allocated mft record as
* well as the mapped, pinned, and locked mft record.
*/
ntfs_debug("Returning opened, allocated %sinode 0x%llx.",
base_ni ? "extent " : "", (long long)bit);
*mrec = m;
return ni;
undo_data_init:
write_lock_irqsave(&mft_ni->size_lock, flags);
mft_ni->initialized_size = old_data_initialized;
i_size_write(vol->mft_ino, old_data_size);
write_unlock_irqrestore(&mft_ni->size_lock, flags);
goto undo_mftbmp_alloc_nolock;
undo_mftbmp_alloc:
down_write(&vol->mftbmp_lock);
undo_mftbmp_alloc_nolock:
if (ntfs_bitmap_clear_bit(vol->mftbmp_ino, bit)) {
ntfs_error(vol->sb, "Failed to clear bit in mft bitmap.%s", es);
NVolSetErrors(vol);
}
up_write(&vol->mftbmp_lock);
err_out:
return ERR_PTR(err);
max_err_out:
ntfs_warning(vol->sb, "Cannot allocate mft record because the maximum "
"number of inodes (2^32) has already been reached.");
up_write(&vol->mftbmp_lock);
return ERR_PTR(-ENOSPC);
}
/**
* ntfs_extent_mft_record_free - free an extent mft record on an ntfs volume
* @ni: ntfs inode of the mapped extent mft record to free
* @m: mapped extent mft record of the ntfs inode @ni
*
* Free the mapped extent mft record @m of the extent ntfs inode @ni.
*
* Note that this function unmaps the mft record and closes and destroys @ni
* internally and hence you cannot use either @ni nor @m any more after this
* function returns success.
*
* On success return 0 and on error return -errno. @ni and @m are still valid
* in this case and have not been freed.
*
* For some errors an error message is displayed and the success code 0 is
* returned and the volume is then left dirty on umount. This makes sense in
* case we could not rollback the changes that were already done since the
* caller no longer wants to reference this mft record so it does not matter to
* the caller if something is wrong with it as long as it is properly detached
* from the base inode.
*/
int ntfs_extent_mft_record_free(ntfs_inode *ni, MFT_RECORD *m)
{
unsigned long mft_no = ni->mft_no;
ntfs_volume *vol = ni->vol;
ntfs_inode *base_ni;
ntfs_inode **extent_nis;
int i, err;
le16 old_seq_no;
u16 seq_no;
BUG_ON(NInoAttr(ni));
BUG_ON(ni->nr_extents != -1);
mutex_lock(&ni->extent_lock);
base_ni = ni->ext.base_ntfs_ino;
mutex_unlock(&ni->extent_lock);
BUG_ON(base_ni->nr_extents <= 0);
ntfs_debug("Entering for extent inode 0x%lx, base inode 0x%lx.\n",
mft_no, base_ni->mft_no);
mutex_lock(&base_ni->extent_lock);
/* Make sure we are holding the only reference to the extent inode. */
if (atomic_read(&ni->count) > 2) {
ntfs_error(vol->sb, "Tried to free busy extent inode 0x%lx, "
"not freeing.", base_ni->mft_no);
mutex_unlock(&base_ni->extent_lock);
return -EBUSY;
}
/* Dissociate the ntfs inode from the base inode. */
extent_nis = base_ni->ext.extent_ntfs_inos;
err = -ENOENT;
for (i = 0; i < base_ni->nr_extents; i++) {
if (ni != extent_nis[i])
continue;
extent_nis += i;
base_ni->nr_extents--;
memmove(extent_nis, extent_nis + 1, (base_ni->nr_extents - i) *
sizeof(ntfs_inode*));
err = 0;
break;
}
mutex_unlock(&base_ni->extent_lock);
if (unlikely(err)) {
ntfs_error(vol->sb, "Extent inode 0x%lx is not attached to "
"its base inode 0x%lx.", mft_no,
base_ni->mft_no);
BUG();
}
/*
* The extent inode is no longer attached to the base inode so no one
* can get a reference to it any more.
*/
/* Mark the mft record as not in use. */
m->flags &= ~MFT_RECORD_IN_USE;
/* Increment the sequence number, skipping zero, if it is not zero. */
old_seq_no = m->sequence_number;
seq_no = le16_to_cpu(old_seq_no);
if (seq_no == 0xffff)
seq_no = 1;
else if (seq_no)
seq_no++;
m->sequence_number = cpu_to_le16(seq_no);
/*
* Set the ntfs inode dirty and write it out. We do not need to worry
* about the base inode here since whatever caused the extent mft
* record to be freed is guaranteed to do it already.
*/
NInoSetDirty(ni);
err = write_mft_record(ni, m, 0);
if (unlikely(err)) {
ntfs_error(vol->sb, "Failed to write mft record 0x%lx, not "
"freeing.", mft_no);
goto rollback;
}
rollback_error:
/* Unmap and throw away the now freed extent inode. */
unmap_extent_mft_record(ni);
ntfs_clear_extent_inode(ni);
/* Clear the bit in the $MFT/$BITMAP corresponding to this record. */
down_write(&vol->mftbmp_lock);
err = ntfs_bitmap_clear_bit(vol->mftbmp_ino, mft_no);
up_write(&vol->mftbmp_lock);
if (unlikely(err)) {
/*
* The extent inode is gone but we failed to deallocate it in
* the mft bitmap. Just emit a warning and leave the volume
* dirty on umount.
*/
ntfs_error(vol->sb, "Failed to clear bit in mft bitmap.%s", es);
NVolSetErrors(vol);
}
return 0;
rollback:
/* Rollback what we did... */
mutex_lock(&base_ni->extent_lock);
extent_nis = base_ni->ext.extent_ntfs_inos;
if (!(base_ni->nr_extents & 3)) {
int new_size = (base_ni->nr_extents + 4) * sizeof(ntfs_inode*);
extent_nis = kmalloc(new_size, GFP_NOFS);
if (unlikely(!extent_nis)) {
ntfs_error(vol->sb, "Failed to allocate internal "
"buffer during rollback.%s", es);
mutex_unlock(&base_ni->extent_lock);
NVolSetErrors(vol);
goto rollback_error;
}
if (base_ni->nr_extents) {
BUG_ON(!base_ni->ext.extent_ntfs_inos);
memcpy(extent_nis, base_ni->ext.extent_ntfs_inos,
new_size - 4 * sizeof(ntfs_inode*));
kfree(base_ni->ext.extent_ntfs_inos);
}
base_ni->ext.extent_ntfs_inos = extent_nis;
}
m->flags |= MFT_RECORD_IN_USE;
m->sequence_number = old_seq_no;
extent_nis[base_ni->nr_extents++] = ni;
mutex_unlock(&base_ni->extent_lock);
mark_mft_record_dirty(ni);
return err;
}
#endif /* NTFS_RW */
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