Illumos 5139 - SEEK_HOLE failed to report a hole at end of file

5139 SEEK_HOLE failed to report a hole at end of file
Reviewed by: Adam Leventhal <adam.leventhal@delphix.com>
Reviewed by: Alex Reece <alex.reece@delphix.com>
Reviewed by: Christopher Siden <christopher.siden@delphix.com>
Reviewed by: George Wilson <george.wilson@delphix.com>
Reviewed by: Max Grossman <max.grossman@delphix.com>
Reviewed by: Peng Dai <peng.dai@delphix.com>
Reviewed by: Richard Elling <richard.elling@gmail.com>
Approved by: Dan McDonald <danmcd@omniti.com>

References:
  https://www.illumos.org/issues/5139
  https://github.com/illumos/illumos-gate/commit/0fbc0cd

Ported by: Turbo Fredriksson <turbo@bayour.com>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Closes #2714
This commit is contained in:
Matthew Ahrens 2014-09-17 17:25:10 +02:00 committed by Brian Behlendorf
parent 843b4aad50
commit d97aa48f7c
2 changed files with 21 additions and 9 deletions

View File

@ -1902,6 +1902,15 @@ dnode_next_offset(dnode_t *dn, int flags, uint64_t *offset,
flags, offset, lvl, blkfill, txg);
}
/*
* There's always a "virtual hole" at the end of the object, even
* if all BP's which physically exist are non-holes.
*/
if ((flags & DNODE_FIND_HOLE) && error == ESRCH && txg == 0 &&
minlvl == 1 && blkfill == 1 && !(flags & DNODE_FIND_BACKWARDS)) {
error = 0;
}
if (error == 0 && (flags & DNODE_FIND_BACKWARDS ?
initial_offset < *offset : initial_offset > *offset))
error = SET_ERROR(ESRCH);

View File

@ -274,16 +274,19 @@ zfs_holey_common(struct inode *ip, int cmd, loff_t *off)
error = dmu_offset_next(ZTOZSB(zp)->z_os, zp->z_id, hole, &noff);
/* end of file? */
if ((error == ESRCH) || (noff > file_sz)) {
/*
* Handle the virtual hole at the end of file.
*/
if (hole) {
*off = file_sz;
return (0);
}
if (error == ESRCH)
return (SET_ERROR(ENXIO));
/*
* We could find a hole that begins after the logical end-of-file,
* because dmu_offset_next() only works on whole blocks. If the
* EOF falls mid-block, then indicate that the "virtual hole"
* at the end of the file begins at the logical EOF, rather than
* at the end of the last block.
*/
if (noff > file_sz) {
ASSERT(hole);
noff = file_sz;
}
if (noff < *off)