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Be less conservative with a recently added KASSERT. Certain edge

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cases with file fragments and read-write mmap's can lead to a situation
    where a VM page has odd dirty bits, e.g. 0xFC - due to being dirtied by
    an mmap and only the fragment (representing a non-page-aligned end of
    file) synced via a filesystem buffer.  A correct solution that
    guarentees consistent m->dirty for the file EOF case is being
    worked on.  In the mean time we can't be so conservative in the
    KASSERT.
This commit is contained in:
Matthew Dillon 2000-12-11 07:52:47 +00:00
parent 578dc923a9
commit 02fa91d35e
1 changed files with 4 additions and 1 deletions

5
sys/vm/vm_pageout.c

@ -372,10 +372,13 @@ vm_pageout_flush(mc, count, flags)
* *
* We do not have to fixup the clean/dirty bits here... we can * We do not have to fixup the clean/dirty bits here... we can
* allow the pager to do it after the I/O completes. * allow the pager to do it after the I/O completes.
*
* NOTE! mc[i]->dirty may be partial or fragmented due to an
* edge case with file fragments.
*/ */
for (i = 0; i < count; i++) { for (i = 0; i < count; i++) {
KASSERT(mc[i]->valid == VM_PAGE_BITS_ALL && mc[i]->dirty == VM_PAGE_BITS_ALL, ("vm_pageout_flush page %p index %d/%d: partially dirty page", mc[i], i, count)); KASSERT(mc[i]->valid == VM_PAGE_BITS_ALL, ("vm_pageout_flush page %p index %d/%d: partially invalid page", mc[i], i, count));
vm_page_io_start(mc[i]); vm_page_io_start(mc[i]);
vm_page_protect(mc[i], VM_PROT_READ); vm_page_protect(mc[i], VM_PROT_READ);
} }