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-rw-r--r--fs/ntfs/mft.c157
1 files changed, 113 insertions, 44 deletions
diff --git a/fs/ntfs/mft.c b/fs/ntfs/mft.c
index dfa85ac2f8b..20011e02f5b 100644
--- a/fs/ntfs/mft.c
+++ b/fs/ntfs/mft.c
@@ -45,6 +45,7 @@
*/
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;
@@ -60,13 +61,14 @@ static inline MFT_RECORD *map_mft_record_page(ntfs_inode *ni)
index = ni->mft_no << vol->mft_record_size_bits >> PAGE_CACHE_SHIFT;
ofs = (ni->mft_no << vol->mft_record_size_bits) & ~PAGE_CACHE_MASK;
+ i_size = i_size_read(mft_vi);
/* The maximum valid index into the page cache for $MFT's data. */
- end_index = mft_vi->i_size >> PAGE_CACHE_SHIFT;
+ end_index = i_size >> PAGE_CACHE_SHIFT;
/* If the wanted index is out of bounds the mft record doesn't exist. */
if (unlikely(index >= end_index)) {
- if (index > end_index || (mft_vi->i_size & ~PAGE_CACHE_MASK) <
- ofs + vol->mft_record_size) {
+ if (index > end_index || (i_size & ~PAGE_CACHE_MASK) < ofs +
+ vol->mft_record_size) {
page = ERR_PTR(-ENOENT);
ntfs_error(vol->sb, "Attemt to read mft record 0x%lx, "
"which is beyond the end of the mft. "
@@ -1121,6 +1123,7 @@ 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;
@@ -1134,9 +1137,13 @@ static int ntfs_mft_bitmap_find_and_alloc_free_rec_nolock(ntfs_volume *vol,
* 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;
@@ -1263,6 +1270,7 @@ 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;
@@ -1286,8 +1294,10 @@ static int ntfs_mft_bitmap_extend_allocation_nolock(ntfs_volume *vol)
* mft bitmap cannot be zero so we are ok to do this.
* ntfs_find_vcn() returns the runlist locked on success.
*/
- rl = ntfs_find_vcn(mftbmp_ni, (mftbmp_ni->allocated_size - 1) >>
- vol->cluster_size_bits, TRUE);
+ read_lock_irqsave(&mftbmp_ni->size_lock, flags);
+ ll = mftbmp_ni->allocated_size;
+ read_unlock_irqrestore(&mftbmp_ni->size_lock, flags);
+ rl = ntfs_find_vcn(mftbmp_ni, (ll - 1) >> vol->cluster_size_bits, TRUE);
if (unlikely(IS_ERR(rl) || !rl->length || rl->lcn < 0)) {
ntfs_error(vol->sb, "Failed to determine last allocated "
"cluster of mft bitmap attribute.");
@@ -1458,9 +1468,11 @@ static int ntfs_mft_bitmap_extend_allocation_nolock(ntfs_volume *vol)
}
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);
@@ -1476,7 +1488,9 @@ restore_undo_alloc:
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);
@@ -1550,6 +1564,7 @@ undo_alloc:
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;
@@ -1583,7 +1598,8 @@ static int ntfs_mft_bitmap_extend_initialized_nolock(ntfs_volume *vol)
goto put_err_out;
}
a = ctx->attr;
- old_data_size = mftbmp_vi->i_size;
+ 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
@@ -1593,11 +1609,12 @@ static int ntfs_mft_bitmap_extend_initialized_nolock(ntfs_volume *vol)
mftbmp_ni->initialized_size += 8;
a->data.non_resident.initialized_size =
cpu_to_sle64(mftbmp_ni->initialized_size);
- if (mftbmp_ni->initialized_size > mftbmp_vi->i_size) {
- mftbmp_vi->i_size = 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_vi->i_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);
@@ -1636,22 +1653,28 @@ unm_err_out:
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 (mftbmp_vi->i_size != old_data_size) {
- mftbmp_vi->i_size = old_data_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)mftbmp_vi->i_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;
}
@@ -1679,7 +1702,8 @@ static int ntfs_mft_data_extend_allocation_nolock(ntfs_volume *vol)
{
LCN lcn;
VCN old_last_vcn;
- s64 min_nr, nr, ll = 0;
+ s64 min_nr, nr, ll;
+ unsigned long flags;
ntfs_inode *mft_ni;
runlist_element *rl, *rl2;
ntfs_attr_search_ctx *ctx = NULL;
@@ -1697,8 +1721,10 @@ static int ntfs_mft_data_extend_allocation_nolock(ntfs_volume *vol)
* attribute cannot be zero so we are ok to do this.
* ntfs_find_vcn() returns the runlist locked on success.
*/
- rl = ntfs_find_vcn(mft_ni, (mft_ni->allocated_size - 1) >>
- vol->cluster_size_bits, TRUE);
+ read_lock_irqsave(&mft_ni->size_lock, flags);
+ ll = mft_ni->allocated_size;
+ read_unlock_irqrestore(&mft_ni->size_lock, flags);
+ rl = ntfs_find_vcn(mft_ni, (ll - 1) >> vol->cluster_size_bits, TRUE);
if (unlikely(IS_ERR(rl) || !rl->length || rl->lcn < 0)) {
ntfs_error(vol->sb, "Failed to determine last allocated "
"cluster of mft data attribute.");
@@ -1710,8 +1736,7 @@ static int ntfs_mft_data_extend_allocation_nolock(ntfs_volume *vol)
return ret;
}
lcn = rl->lcn + rl->length;
- ntfs_debug("Last lcn of mft data attribute is 0x%llx.",
- (long long)lcn);
+ 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)
@@ -1721,12 +1746,13 @@ static int ntfs_mft_data_extend_allocation_nolock(ntfs_volume *vol)
if (!nr)
nr = min_nr;
/* Ensure we do not go above 2^32-1 mft records. */
- if (unlikely((mft_ni->allocated_size +
- (nr << vol->cluster_size_bits)) >>
+ 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((mft_ni->allocated_size +
- (nr << vol->cluster_size_bits)) >>
+ 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 "
@@ -1875,9 +1901,11 @@ static int ntfs_mft_data_extend_allocation_nolock(ntfs_volume *vol)
}
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);
@@ -1892,7 +1920,9 @@ restore_undo_alloc:
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);
@@ -2036,6 +2066,7 @@ static int ntfs_mft_record_layout(const ntfs_volume *vol, const s64 mft_no,
*/
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;
@@ -2051,10 +2082,11 @@ static int ntfs_mft_record_format(const ntfs_volume *vol, const s64 mft_no)
index = mft_no << vol->mft_record_size_bits >> PAGE_CACHE_SHIFT;
ofs = (mft_no << vol->mft_record_size_bits) & ~PAGE_CACHE_MASK;
/* The maximum valid index into the page cache for $MFT's data. */
- end_index = mft_vi->i_size >> PAGE_CACHE_SHIFT;
+ i_size = i_size_read(mft_vi);
+ end_index = i_size >> PAGE_CACHE_SHIFT;
if (unlikely(index >= end_index)) {
if (unlikely(index > end_index || ofs + vol->mft_record_size >=
- (mft_vi->i_size & ~PAGE_CACHE_MASK))) {
+ (i_size & ~PAGE_CACHE_MASK))) {
ntfs_error(vol->sb, "Tried to format non-existing mft "
"record 0x%llx.", (long long)mft_no);
return -ENOENT;
@@ -2188,6 +2220,7 @@ 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;
@@ -2237,9 +2270,13 @@ ntfs_inode *ntfs_mft_record_alloc(ntfs_volume *vol, const int mode,
* 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;
- if (mftbmp_ni->initialized_size << 3 > ll &&
- mftbmp_ni->initialized_size > 3) {
+ 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;
@@ -2254,15 +2291,18 @@ ntfs_inode *ntfs_mft_record_alloc(ntfs_volume *vol, const int mode,
* mft record that we can allocate.
* Note: The smallest mft record we allocate is mft record 24.
*/
- bit = mftbmp_ni->initialized_size << 3;
+ 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)mftbmp_ni->allocated_size,
- (long long)vol->mftbmp_ino->i_size,
- (long long)mftbmp_ni->initialized_size);
- if (mftbmp_ni->initialized_size + 8 > mftbmp_ni->allocated_size) {
+ (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);
@@ -2270,12 +2310,16 @@ ntfs_inode *ntfs_mft_record_alloc(ntfs_volume *vol, const int mode,
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)vol->mftbmp_ino->i_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
@@ -2287,12 +2331,16 @@ ntfs_inode *ntfs_mft_record_alloc(ntfs_volume *vol, const int mode,
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 extention: "
"allocated_size 0x%llx, data_size 0x%llx, "
"initialized_size 0x%llx.",
(long long)mftbmp_ni->allocated_size,
- (long long)vol->mftbmp_ino->i_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. */
@@ -2314,7 +2362,10 @@ have_alloc_rec:
* parallel allocation could allocate the same mft record as this one.
*/
ll = (bit + 1) << vol->mft_record_size_bits;
- if (ll <= mft_ni->initialized_size) {
+ 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;
}
@@ -2325,25 +2376,32 @@ have_alloc_rec:
* 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);
+ old_data_size = mft_ni->allocated_size;
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)vol->mft_ino->i_size,
+ (long long)old_data_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);
+ while (ll > old_data_size) {
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;
}
+#ifdef DEBUG
+ 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)vol->mft_ino->i_size,
+ (long long)i_size_read(vol->mft_ino),
(long long)mft_ni->initialized_size);
+ read_unlock_irqrestore(&mft_ni->size_lock, flags);
+#endif /* DEBUG */
}
/*
* Extend mft data initialized size (and data size of course) to reach
@@ -2352,6 +2410,7 @@ have_alloc_rec:
* 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) {
@@ -2360,8 +2419,9 @@ have_alloc_rec:
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 > vol->mft_ino->i_size)
- vol->mft_ino->i_size = new_initialized_size;
+ 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);
@@ -2369,8 +2429,10 @@ have_alloc_rec:
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);
@@ -2396,22 +2458,27 @@ have_alloc_rec:
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(vol->mft_ino->i_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)vol->mft_ino->i_size,
+ (long long)i_size_read(vol->mft_ino),
(long long)mft_ni->initialized_size);
- BUG_ON(vol->mft_ino->i_size > mft_ni->allocated_size);
- BUG_ON(mft_ni->initialized_size > vol->mft_ino->i_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
@@ -2652,8 +2719,10 @@ mft_rec_already_initialized:
*mrec = m;
return ni;
undo_data_init:
+ write_lock_irqsave(&mft_ni->size_lock, flags);
mft_ni->initialized_size = old_data_initialized;
- vol->mft_ino->i_size = old_data_size;
+ 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);