diff options
author | Anton Altaparmakov <aia21@cantab.net> | 2005-09-20 09:19:30 -0400 |
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committer | Anton Altaparmakov <aia21@cantab.net> | 2005-09-20 09:19:30 -0400 |
commit | eed8b2dee7cff46dd4bf5b82dc53465d229162ba (patch) | |
tree | 1508bedde4dda971c56dc30c7edf1e36bfbefc9e /fs | |
parent | 676d55ae30ea3b688f0386f70553489f25f24d55 (diff) |
NTFS: More runlist handling fixes from Richard Russon and myself.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/ntfs/runlist.c | 55 |
1 files changed, 33 insertions, 22 deletions
diff --git a/fs/ntfs/runlist.c b/fs/ntfs/runlist.c index e2665d011d72..061b5ff6b73c 100644 --- a/fs/ntfs/runlist.c +++ b/fs/ntfs/runlist.c | |||
@@ -158,17 +158,21 @@ static inline BOOL ntfs_are_rl_mergeable(runlist_element *dst, | |||
158 | BUG_ON(!dst); | 158 | BUG_ON(!dst); |
159 | BUG_ON(!src); | 159 | BUG_ON(!src); |
160 | 160 | ||
161 | if ((dst->lcn < 0) || (src->lcn < 0)) { /* Are we merging holes? */ | 161 | /* We can merge unmapped regions even if they are misaligned. */ |
162 | if (dst->lcn == LCN_HOLE && src->lcn == LCN_HOLE) | 162 | if ((dst->lcn == LCN_RL_NOT_MAPPED) && (src->lcn == LCN_RL_NOT_MAPPED)) |
163 | return TRUE; | 163 | return TRUE; |
164 | /* If the runs are misaligned, we cannot merge them. */ | ||
165 | if ((dst->vcn + dst->length) != src->vcn) | ||
164 | return FALSE; | 166 | return FALSE; |
165 | } | 167 | /* If both runs are non-sparse and contiguous, we can merge them. */ |
166 | if ((dst->lcn + dst->length) != src->lcn) /* Are the runs contiguous? */ | 168 | if ((dst->lcn >= 0) && (src->lcn >= 0) && |
167 | return FALSE; | 169 | ((dst->lcn + dst->length) == src->lcn)) |
168 | if ((dst->vcn + dst->length) != src->vcn) /* Are the runs misaligned? */ | 170 | return TRUE; |
169 | return FALSE; | 171 | /* If we are merging two holes, we can merge them. */ |
170 | 172 | if ((dst->lcn == LCN_HOLE) && (src->lcn == LCN_HOLE)) | |
171 | return TRUE; | 173 | return TRUE; |
174 | /* Cannot merge. */ | ||
175 | return FALSE; | ||
172 | } | 176 | } |
173 | 177 | ||
174 | /** | 178 | /** |
@@ -214,14 +218,15 @@ static inline void __ntfs_rl_merge(runlist_element *dst, runlist_element *src) | |||
214 | static inline runlist_element *ntfs_rl_append(runlist_element *dst, | 218 | static inline runlist_element *ntfs_rl_append(runlist_element *dst, |
215 | int dsize, runlist_element *src, int ssize, int loc) | 219 | int dsize, runlist_element *src, int ssize, int loc) |
216 | { | 220 | { |
217 | BOOL right; /* Right end of @src needs merging. */ | 221 | BOOL right = FALSE; /* Right end of @src needs merging. */ |
218 | int marker; /* End of the inserted runs. */ | 222 | int marker; /* End of the inserted runs. */ |
219 | 223 | ||
220 | BUG_ON(!dst); | 224 | BUG_ON(!dst); |
221 | BUG_ON(!src); | 225 | BUG_ON(!src); |
222 | 226 | ||
223 | /* First, check if the right hand end needs merging. */ | 227 | /* First, check if the right hand end needs merging. */ |
224 | right = ntfs_are_rl_mergeable(src + ssize - 1, dst + loc + 1); | 228 | if ((loc + 1) < dsize) |
229 | right = ntfs_are_rl_mergeable(src + ssize - 1, dst + loc + 1); | ||
225 | 230 | ||
226 | /* Space required: @dst size + @src size, less one if we merged. */ | 231 | /* Space required: @dst size + @src size, less one if we merged. */ |
227 | dst = ntfs_rl_realloc(dst, dsize, dsize + ssize - right); | 232 | dst = ntfs_rl_realloc(dst, dsize, dsize + ssize - right); |
@@ -377,20 +382,21 @@ static inline runlist_element *ntfs_rl_replace(runlist_element *dst, | |||
377 | int dsize, runlist_element *src, int ssize, int loc) | 382 | int dsize, runlist_element *src, int ssize, int loc) |
378 | { | 383 | { |
379 | BOOL left = FALSE; /* Left end of @src needs merging. */ | 384 | BOOL left = FALSE; /* Left end of @src needs merging. */ |
380 | BOOL right; /* Right end of @src needs merging. */ | 385 | BOOL right = FALSE; /* Right end of @src needs merging. */ |
381 | int tail; /* Start of tail of @dst. */ | 386 | int tail; /* Start of tail of @dst. */ |
382 | int marker; /* End of the inserted runs. */ | 387 | int marker; /* End of the inserted runs. */ |
383 | 388 | ||
384 | BUG_ON(!dst); | 389 | BUG_ON(!dst); |
385 | BUG_ON(!src); | 390 | BUG_ON(!src); |
386 | 391 | ||
387 | /* First, merge the left and right ends, if necessary. */ | 392 | /* First, see if the left and right ends need merging. */ |
388 | right = ntfs_are_rl_mergeable(src + ssize - 1, dst + loc + 1); | 393 | if ((loc + 1) < dsize) |
394 | right = ntfs_are_rl_mergeable(src + ssize - 1, dst + loc + 1); | ||
389 | if (loc > 0) | 395 | if (loc > 0) |
390 | left = ntfs_are_rl_mergeable(dst + loc - 1, src); | 396 | left = ntfs_are_rl_mergeable(dst + loc - 1, src); |
391 | /* | 397 | /* |
392 | * Allocate some space. We will need less if the left, right, or both | 398 | * Allocate some space. We will need less if the left, right, or both |
393 | * ends were merged. | 399 | * ends get merged. |
394 | */ | 400 | */ |
395 | dst = ntfs_rl_realloc(dst, dsize, dsize + ssize - left - right); | 401 | dst = ntfs_rl_realloc(dst, dsize, dsize + ssize - left - right); |
396 | if (IS_ERR(dst)) | 402 | if (IS_ERR(dst)) |
@@ -399,21 +405,26 @@ static inline runlist_element *ntfs_rl_replace(runlist_element *dst, | |||
399 | * We are guaranteed to succeed from here so can start modifying the | 405 | * We are guaranteed to succeed from here so can start modifying the |
400 | * original runlists. | 406 | * original runlists. |
401 | */ | 407 | */ |
408 | |||
409 | /* First, merge the left and right ends, if necessary. */ | ||
402 | if (right) | 410 | if (right) |
403 | __ntfs_rl_merge(src + ssize - 1, dst + loc + 1); | 411 | __ntfs_rl_merge(src + ssize - 1, dst + loc + 1); |
404 | if (left) | 412 | if (left) |
405 | __ntfs_rl_merge(dst + loc - 1, src); | 413 | __ntfs_rl_merge(dst + loc - 1, src); |
406 | /* | 414 | /* |
407 | * First run of @dst that needs to be moved out of the way to make | 415 | * Offset of the tail of @dst. This needs to be moved out of the way |
408 | * space for the runs to be copied from @src, i.e. the first run of the | 416 | * to make space for the runs to be copied from @src, i.e. the first |
409 | * tail of @dst. | 417 | * run of the tail of @dst. |
418 | * Nominally, @tail equals @loc + 1, i.e. location, skipping the | ||
419 | * replaced run. However, if @right, then one of @dst's runs is | ||
420 | * already merged into @src. | ||
410 | */ | 421 | */ |
411 | tail = loc + right + 1; | 422 | tail = loc + right + 1; |
412 | /* | 423 | /* |
413 | * First run after the @src runs that have been inserted, i.e. where | 424 | * First run after the @src runs that have been inserted, i.e. where |
414 | * the tail of @dst needs to be moved to. | 425 | * the tail of @dst needs to be moved to. |
415 | * Nominally, marker equals @loc + @ssize, i.e. location + number of | 426 | * Nominally, @marker equals @loc + @ssize, i.e. location + number of |
416 | * runs in @src). However, if @left, then the first run in @src has | 427 | * runs in @src. However, if @left, then the first run in @src has |
417 | * been merged with one in @dst. | 428 | * been merged with one in @dst. |
418 | */ | 429 | */ |
419 | marker = loc + ssize - left; | 430 | marker = loc + ssize - left; |