Commit 2b831ac6bc87d3cbcbb1a8816827b6923403e461
Committed by
Dave Chinner
Dave Chinner
1 parent
bf4a5af20d
Exists in
ti-lsk-linux-4.1.y
and in
10 other branches
xfs: bulkstat chunk-formatter has issues
The loop construct has issues: - clustidx is completely unused, so remove it. - the loop tries to be smart by terminating when the "freecount" tells it that all inodes are free. Just drop it as in most cases we have to scan all inodes in the chunk anyway. - move the "user buffer left" condition check to the only point where we consume space int eh user buffer. - move the initialisation of agino out of the loop, leaving just a simple loop control logic using the clusteridx. Also, double handling of the user buffer variables leads to problems tracking the current state - use the cursor variables directly rather than keeping local copies and then having to update the cursor before returning. cc: <stable@vger.kernel.org> # 3.17 Signed-off-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Signed-off-by: Dave Chinner <david@fromorbit.com>
Showing 1 changed file with 24 additions and 34 deletions Side-by-side Diff
fs/xfs/xfs_itable.c
| ... | ... | @@ -283,59 +283,49 @@ |
| 283 | 283 | xfs_ino_t *lastino) |
| 284 | 284 | { |
| 285 | 285 | char __user **ubufp = acp->ac_ubuffer; |
| 286 | - int ubleft = acp->ac_ubleft; | |
| 287 | - int ubelem = acp->ac_ubelem; | |
| 288 | - int chunkidx, clustidx; | |
| 286 | + int chunkidx; | |
| 289 | 287 | int error = 0; |
| 290 | 288 | xfs_agino_t agino; |
| 291 | 289 | |
| 292 | - for (agino = irbp->ir_startino, chunkidx = clustidx = 0; | |
| 293 | - XFS_BULKSTAT_UBLEFT(ubleft) && | |
| 294 | - irbp->ir_freecount < XFS_INODES_PER_CHUNK; | |
| 295 | - chunkidx++, clustidx++, agino++) { | |
| 296 | - int fmterror; /* bulkstat formatter result */ | |
| 290 | + agino = irbp->ir_startino; | |
| 291 | + for (chunkidx = 0; chunkidx < XFS_INODES_PER_CHUNK; | |
| 292 | + chunkidx++, agino++) { | |
| 293 | + int fmterror; | |
| 297 | 294 | int ubused; |
| 298 | 295 | xfs_ino_t ino = XFS_AGINO_TO_INO(mp, agno, agino); |
| 299 | 296 | |
| 300 | - ASSERT(chunkidx < XFS_INODES_PER_CHUNK); | |
| 301 | - | |
| 302 | 297 | /* Skip if this inode is free */ |
| 303 | 298 | if (XFS_INOBT_MASK(chunkidx) & irbp->ir_free) { |
| 304 | 299 | *lastino = ino; |
| 305 | 300 | continue; |
| 306 | 301 | } |
| 307 | 302 | |
| 308 | - /* | |
| 309 | - * Count used inodes as free so we can tell when the | |
| 310 | - * chunk is used up. | |
| 311 | - */ | |
| 312 | - irbp->ir_freecount++; | |
| 313 | - | |
| 314 | 303 | /* Get the inode and fill in a single buffer */ |
| 315 | 304 | ubused = statstruct_size; |
| 316 | - error = formatter(mp, ino, *ubufp, ubleft, &ubused, &fmterror); | |
| 317 | - if (fmterror == BULKSTAT_RV_NOTHING) { | |
| 318 | - if (error && error != -ENOENT && error != -EINVAL) { | |
| 319 | - ubleft = 0; | |
| 320 | - break; | |
| 321 | - } | |
| 322 | - *lastino = ino; | |
| 323 | - continue; | |
| 324 | - } | |
| 325 | - if (fmterror == BULKSTAT_RV_GIVEUP) { | |
| 326 | - ubleft = 0; | |
| 305 | + error = formatter(mp, ino, *ubufp, acp->ac_ubleft, | |
| 306 | + &ubused, &fmterror); | |
| 307 | + if (fmterror == BULKSTAT_RV_GIVEUP || | |
| 308 | + (error && error != -ENOENT && error != -EINVAL)) { | |
| 309 | + acp->ac_ubleft = 0; | |
| 327 | 310 | ASSERT(error); |
| 328 | 311 | break; |
| 329 | 312 | } |
| 330 | - if (*ubufp) | |
| 331 | - *ubufp += ubused; | |
| 332 | - ubleft -= ubused; | |
| 333 | - ubelem++; | |
| 313 | + | |
| 314 | + /* be careful not to leak error if at end of chunk */ | |
| 315 | + if (fmterror == BULKSTAT_RV_NOTHING || error) { | |
| 316 | + *lastino = ino; | |
| 317 | + error = 0; | |
| 318 | + continue; | |
| 319 | + } | |
| 320 | + | |
| 321 | + *ubufp += ubused; | |
| 322 | + acp->ac_ubleft -= ubused; | |
| 323 | + acp->ac_ubelem++; | |
| 334 | 324 | *lastino = ino; |
| 335 | - } | |
| 336 | 325 | |
| 337 | - acp->ac_ubleft = ubleft; | |
| 338 | - acp->ac_ubelem = ubelem; | |
| 326 | + if (acp->ac_ubleft < statstruct_size) | |
| 327 | + break; | |
| 328 | + } | |
| 339 | 329 | |
| 340 | 330 | return error; |
| 341 | 331 | } |