diff options
| -rw-r--r-- | sys/uvm/uvm_amap.c | 37 |
1 files changed, 17 insertions, 20 deletions
diff --git a/sys/uvm/uvm_amap.c b/sys/uvm/uvm_amap.c index 310e5e8446f..b49835e74ef 100644 --- a/sys/uvm/uvm_amap.c +++ b/sys/uvm/uvm_amap.c @@ -1,4 +1,4 @@ -/* $OpenBSD: uvm_amap.c,v 1.84 2020/09/25 08:04:48 mpi Exp $ */ +/* $OpenBSD: uvm_amap.c,v 1.85 2020/10/12 08:44:45 mpi Exp $ */ /* $NetBSD: uvm_amap.c,v 1.27 2000/11/25 06:27:59 chs Exp $ */ /* @@ -669,9 +669,7 @@ ReStart: pg = anon->an_page; /* page must be resident since parent is wired */ - if (pg == NULL) - panic("amap_cow_now: non-resident wired page" - " in anon %p", anon); + KASSERT(pg != NULL); /* * if the anon ref count is one, we are safe (the child @@ -740,6 +738,7 @@ ReStart: void amap_splitref(struct vm_aref *origref, struct vm_aref *splitref, vaddr_t offset) { + struct vm_amap *amap = origref->ar_amap; int leftslots; AMAP_B2SLOT(leftslots, offset); @@ -747,17 +746,18 @@ amap_splitref(struct vm_aref *origref, struct vm_aref *splitref, vaddr_t offset) panic("amap_splitref: split at zero offset"); /* now: we have a valid am_mapped array. */ - if (origref->ar_amap->am_nslot - origref->ar_pageoff - leftslots <= 0) + if (amap->am_nslot - origref->ar_pageoff - leftslots <= 0) panic("amap_splitref: map size check failed"); #ifdef UVM_AMAP_PPREF - /* establish ppref before we add a duplicate reference to the amap */ - if (origref->ar_amap->am_ppref == NULL) - amap_pp_establish(origref->ar_amap); + /* Establish ppref before we add a duplicate reference to the amap. */ + if (amap->am_ppref == NULL) + amap_pp_establish(amap); #endif - splitref->ar_amap = origref->ar_amap; - splitref->ar_amap->am_ref++; /* not a share reference */ + /* Note: not a share reference. */ + amap->am_ref++; + splitref->ar_amap = amap; splitref->ar_pageoff = origref->ar_pageoff + leftslots; } @@ -1104,12 +1104,11 @@ amap_add(struct vm_aref *aref, vaddr_t offset, struct vm_anon *anon, slot = UVM_AMAP_SLOTIDX(slot); if (replace) { - if (chunk->ac_anon[slot] == NULL) - panic("amap_add: replacing null anon"); - if (chunk->ac_anon[slot]->an_page != NULL && - (amap->am_flags & AMAP_SHARED) != 0) { - pmap_page_protect(chunk->ac_anon[slot]->an_page, - PROT_NONE); + struct vm_anon *oanon = chunk->ac_anon[slot]; + + KASSERT(oanon != NULL); + if (oanon->an_page && (amap->am_flags & AMAP_SHARED) != 0) { + pmap_page_protect(oanon->an_page, PROT_NONE); /* * XXX: suppose page is supposed to be wired somewhere? */ @@ -1140,12 +1139,10 @@ amap_unadd(struct vm_aref *aref, vaddr_t offset) slot += aref->ar_pageoff; KASSERT(slot < amap->am_nslot); chunk = amap_chunk_get(amap, slot, 0, PR_NOWAIT); - if (chunk == NULL) - panic("amap_unadd: chunk for slot %d not present", slot); + KASSERT(chunk != NULL); slot = UVM_AMAP_SLOTIDX(slot); - if (chunk->ac_anon[slot] == NULL) - panic("amap_unadd: nothing there"); + KASSERT(chunk->ac_anon[slot] != NULL); chunk->ac_anon[slot] = NULL; chunk->ac_usedmap &= ~(1 << slot); |