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vm_map_protect(): move guard handling at the last phase into an empty dedicated helper

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Restructure the first phase slightly, to facilitate further changes.

Reviewed by:	alc, markj
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D41099
This commit is contained in:
Konstantin Belousov 2023-07-28 03:14:07 +03:00
parent aa928a5216
commit 79169929f0
1 changed files with 17 additions and 4 deletions
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21
sys/vm/vm_map.c
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@ -2722,6 +2722,13 @@ vm_map_pmap_enter(vm_map_t map, vm_offset_t addr, vm_prot_t prot,
VM_OBJECT_RUNLOCK(object);
}
static void
vm_map_protect_guard(vm_map_entry_t entry, vm_prot_t new_prot,
vm_prot_t new_maxprot, int flags)
{
MPASS((entry->eflags & MAP_ENTRY_GUARD) != 0);
}
/*
* vm_map_protect:
*
@ -2780,12 +2787,13 @@ vm_map_protect(vm_map_t map, vm_offset_t start, vm_offset_t end,
check_prot |= new_maxprot;
for (entry = first_entry; entry->start < end;
entry = vm_map_entry_succ(entry)) {
if ((entry->eflags & MAP_ENTRY_GUARD) != 0)
continue;
if ((entry->eflags & MAP_ENTRY_IS_SUB_MAP) != 0) {
vm_map_unlock(map);
return (KERN_INVALID_ARGUMENT);
}
if ((entry->eflags & MAP_ENTRY_GUARD) != 0) {
continue;
}
if (!CONTAINS_BITS(entry->max_protection, check_prot)) {
vm_map_unlock(map);
return (KERN_PROTECTION_FAILURE);
@ -2884,10 +2892,15 @@ vm_map_protect(vm_map_t map, vm_offset_t start, vm_offset_t end,
entry->start < end;
vm_map_try_merge_entries(map, prev_entry, entry),
prev_entry = entry, entry = vm_map_entry_succ(entry)) {
if (rv != KERN_SUCCESS ||
(entry->eflags & MAP_ENTRY_GUARD) != 0)
if (rv != KERN_SUCCESS)
continue;
if ((entry->eflags & MAP_ENTRY_GUARD) != 0) {
vm_map_protect_guard(entry, new_prot, new_maxprot,
flags);
continue;
}
old_prot = entry->protection;
if ((flags & VM_MAP_PROTECT_SET_MAXPROT) != 0) {