NTFS: More runlist handling fixes from Richard Russon and myself.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
This commit is contained in:
parent
676d55ae30
commit
eed8b2dee7
@ -158,17 +158,21 @@ static inline BOOL ntfs_are_rl_mergeable(runlist_element *dst,
|
||||
BUG_ON(!dst);
|
||||
BUG_ON(!src);
|
||||
|
||||
if ((dst->lcn < 0) || (src->lcn < 0)) { /* Are we merging holes? */
|
||||
if (dst->lcn == LCN_HOLE && src->lcn == LCN_HOLE)
|
||||
return TRUE;
|
||||
/* We can merge unmapped regions even if they are misaligned. */
|
||||
if ((dst->lcn == LCN_RL_NOT_MAPPED) && (src->lcn == LCN_RL_NOT_MAPPED))
|
||||
return TRUE;
|
||||
/* If the runs are misaligned, we cannot merge them. */
|
||||
if ((dst->vcn + dst->length) != src->vcn)
|
||||
return FALSE;
|
||||
}
|
||||
if ((dst->lcn + dst->length) != src->lcn) /* Are the runs contiguous? */
|
||||
return FALSE;
|
||||
if ((dst->vcn + dst->length) != src->vcn) /* Are the runs misaligned? */
|
||||
return FALSE;
|
||||
|
||||
return TRUE;
|
||||
/* If both runs are non-sparse and contiguous, we can merge them. */
|
||||
if ((dst->lcn >= 0) && (src->lcn >= 0) &&
|
||||
((dst->lcn + dst->length) == src->lcn))
|
||||
return TRUE;
|
||||
/* If we are merging two holes, we can merge them. */
|
||||
if ((dst->lcn == LCN_HOLE) && (src->lcn == LCN_HOLE))
|
||||
return TRUE;
|
||||
/* Cannot merge. */
|
||||
return FALSE;
|
||||
}
|
||||
|
||||
/**
|
||||
@ -214,14 +218,15 @@ static inline void __ntfs_rl_merge(runlist_element *dst, runlist_element *src)
|
||||
static inline runlist_element *ntfs_rl_append(runlist_element *dst,
|
||||
int dsize, runlist_element *src, int ssize, int loc)
|
||||
{
|
||||
BOOL right; /* Right end of @src needs merging. */
|
||||
int marker; /* End of the inserted runs. */
|
||||
BOOL right = FALSE; /* Right end of @src needs merging. */
|
||||
int marker; /* End of the inserted runs. */
|
||||
|
||||
BUG_ON(!dst);
|
||||
BUG_ON(!src);
|
||||
|
||||
/* First, check if the right hand end needs merging. */
|
||||
right = ntfs_are_rl_mergeable(src + ssize - 1, dst + loc + 1);
|
||||
if ((loc + 1) < dsize)
|
||||
right = ntfs_are_rl_mergeable(src + ssize - 1, dst + loc + 1);
|
||||
|
||||
/* Space required: @dst size + @src size, less one if we merged. */
|
||||
dst = ntfs_rl_realloc(dst, dsize, dsize + ssize - right);
|
||||
@ -377,20 +382,21 @@ static inline runlist_element *ntfs_rl_replace(runlist_element *dst,
|
||||
int dsize, runlist_element *src, int ssize, int loc)
|
||||
{
|
||||
BOOL left = FALSE; /* Left end of @src needs merging. */
|
||||
BOOL right; /* Right end of @src needs merging. */
|
||||
BOOL right = FALSE; /* Right end of @src needs merging. */
|
||||
int tail; /* Start of tail of @dst. */
|
||||
int marker; /* End of the inserted runs. */
|
||||
|
||||
BUG_ON(!dst);
|
||||
BUG_ON(!src);
|
||||
|
||||
/* First, merge the left and right ends, if necessary. */
|
||||
right = ntfs_are_rl_mergeable(src + ssize - 1, dst + loc + 1);
|
||||
/* First, see if the left and right ends need merging. */
|
||||
if ((loc + 1) < dsize)
|
||||
right = ntfs_are_rl_mergeable(src + ssize - 1, dst + loc + 1);
|
||||
if (loc > 0)
|
||||
left = ntfs_are_rl_mergeable(dst + loc - 1, src);
|
||||
/*
|
||||
* Allocate some space. We will need less if the left, right, or both
|
||||
* ends were merged.
|
||||
* ends get merged.
|
||||
*/
|
||||
dst = ntfs_rl_realloc(dst, dsize, dsize + ssize - left - right);
|
||||
if (IS_ERR(dst))
|
||||
@ -399,21 +405,26 @@ static inline runlist_element *ntfs_rl_replace(runlist_element *dst,
|
||||
* We are guaranteed to succeed from here so can start modifying the
|
||||
* original runlists.
|
||||
*/
|
||||
|
||||
/* First, merge the left and right ends, if necessary. */
|
||||
if (right)
|
||||
__ntfs_rl_merge(src + ssize - 1, dst + loc + 1);
|
||||
if (left)
|
||||
__ntfs_rl_merge(dst + loc - 1, src);
|
||||
/*
|
||||
* First run of @dst that needs to be moved out of the way to make
|
||||
* space for the runs to be copied from @src, i.e. the first run of the
|
||||
* tail of @dst.
|
||||
* Offset of the tail of @dst. This needs to be moved out of the way
|
||||
* to make space for the runs to be copied from @src, i.e. the first
|
||||
* run of the tail of @dst.
|
||||
* Nominally, @tail equals @loc + 1, i.e. location, skipping the
|
||||
* replaced run. However, if @right, then one of @dst's runs is
|
||||
* already merged into @src.
|
||||
*/
|
||||
tail = loc + right + 1;
|
||||
/*
|
||||
* First run after the @src runs that have been inserted, i.e. where
|
||||
* the tail of @dst needs to be moved to.
|
||||
* Nominally, marker equals @loc + @ssize, i.e. location + number of
|
||||
* runs in @src). However, if @left, then the first run in @src has
|
||||
* Nominally, @marker equals @loc + @ssize, i.e. location + number of
|
||||
* runs in @src. However, if @left, then the first run in @src has
|
||||
* been merged with one in @dst.
|
||||
*/
|
||||
marker = loc + ssize - left;
|
||||
|
Loading…
Reference in New Issue
Block a user