mm: always use this_cpu().get_pgtable() instead of get_init_pgtable_locked()
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We don't use the &mut PageTableRef for anything but dereferencing it into a &mut PageTable. It's the same reason why &T and &[T] are generally prefered over &Box<T> or &Vec<T>. Signed-off-by: Tom Dohrmann <[email protected]>
This safety comment isn't followed by any unsafe code. Signed-off-by: Tom Dohrmann <[email protected]>
Previously we had PageTableRef for this, but all we really need is a static mut reference. Signed-off-by: Tom Dohrmann <[email protected]>
We know that we'll return PageTableRef::Owned and never PageTableRef::Shared, so let's just return the PageBox directly. Signed-off-by: Tom Dohrmann <[email protected]>
This will make it possible to create the pagetables slightly differently depending on where in the boot process this code is called. Signed-off-by: Tom Dohrmann <[email protected]>
There's no need to use the pagetables stored in a global when we can just use the CPUs active pagetables. Signed-off-by: Tom Dohrmann <[email protected]>
INIT_PGTABLE was problematic because it contained a mutable static reference to the same page tables pointed to by the BSPs percpu pagetables. Obviously we should avoid creating two static mutable references pointing to the same memory. Now that code is always using this_cpu().get_pgtables() there's no need for INIT_PGTABLE anymore. Signed-off-by: Tom Dohrmann <[email protected]>
This type is now unused. Signed-off-by: Tom Dohrmann <[email protected]>
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get_init_pgtable_locked()was problematic because the returned mutable reference was aliasing the mutable reference returned inthis_cpu().get_pgtable()in stage2.Removing
get_init_pgtable_locked()now will probably also make it easier to implement isolated pagetables in the future because everything is already only accessingthis_cpu().get_pgtable().