diff options
Diffstat (limited to 'sys/vm/vm_object.c')
| -rw-r--r-- | sys/vm/vm_object.c | 35 |
1 files changed, 31 insertions, 4 deletions
diff --git a/sys/vm/vm_object.c b/sys/vm/vm_object.c index 1df9faf..6da6c9b 100644 --- a/sys/vm/vm_object.c +++ b/sys/vm/vm_object.c @@ -478,8 +478,10 @@ vm_object_terminate(object) /* * vm_object_page_clean * - * Clean all dirty pages in the specified range of object. - * Leaves page on whatever queue it is currently on. + * Clean all dirty pages in the specified range of object. Leaves page + * on whatever queue it is currently on. If NOSYNC is set then do not + * write out pages with PG_NOSYNC set (originally comes from MAP_NOSYNC), + * leaving the object dirty. * * Odd semantics: if start == end, we clean everything. * @@ -503,6 +505,7 @@ vm_object_page_clean(object, start, end, flags) int chkb; int maxb; int i; + int clearobjflags; int pagerflags; vm_page_t maf[vm_pageout_page_count]; vm_page_t mab[vm_pageout_page_count]; @@ -527,12 +530,26 @@ vm_object_page_clean(object, start, end, flags) tend = end; } + /* + * Generally set CLEANCHK interlock and make the page read-only so + * we can then clear the object flags. + * + * However, if this is a nosync mmap then the object is likely to + * stay dirty so do not mess with the page and do not clear the + * object flags. + */ + + clearobjflags = 1; + for(p = TAILQ_FIRST(&object->memq); p; p = TAILQ_NEXT(p, listq)) { vm_page_flag_set(p, PG_CLEANCHK); - vm_page_protect(p, VM_PROT_READ); + if ((flags & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC)) + clearobjflags = 0; + else + vm_page_protect(p, VM_PROT_READ); } - if ((tstart == 0) && (tend == object->size)) { + if (clearobjflags && (tstart == 0) && (tend == object->size)) { vm_object_clear_flag(object, OBJ_WRITEABLE|OBJ_MIGHTBEDIRTY); } @@ -557,6 +574,16 @@ rescan: continue; } + /* + * If we have been asked to skip nosync pages and this is a + * nosync page, skip it. Note that the object flags were + * not cleared in this case so we do not have to set them. + */ + if ((flags & OBJPC_NOSYNC) && (p->flags & PG_NOSYNC)) { + vm_page_flag_clear(p, PG_CLEANCHK); + continue; + } + s = splvm(); while (vm_page_sleep_busy(p, TRUE, "vpcwai")) { if (object->generation != curgeneration) { |
