Add minimal support for creating stage 2 IPA -> PA mappings. For this we
need to:
- Create a new vmid set to allocate a vmid for each Virtual Machine
- Add the missing stage 2 attributes
- Use these in pmap_enter to create a new mapping
- Handle stage 2 faults
The vmid set is based on the current asid set that was generalised in
r358328. It adds a function pointer for bhyve to use when the kernel needs
to reset the vmid set. This will need to call into EL2 and invalidate the
TLB.
The stage 2 attributes have been added. To simplify setting these fields
two new functions are added to get the memory type and protection fields.
These are slightly different on stage 1 and stage 2 tables. We then use
them in pmap_enter to set the new level 3 entry to be stored.
The D-cache on all entries is cleaned to the point of coherency. This is
to allow the data to be visible to the VM. To allow for userspace to load
code when creating a new executable entry an invalid entry is created. When
the VM tried to use it the I-cache is invalidated. As the D-cache has
already been cleaned this will ensure the I-cache is synchronised with the
D-cache.
When the hardware implements a VPIPT I-cache we need to either have the
correct VMID set or invalidate it from EL2. As the host kernel will have
the wrong VMID set we need to call into EL2 to clean it. For this a second
function pointer is added that is called when this invalidation is needed.
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D23875
In preperation for adding bhyve support to arm64 we need to split the
stage 1 and stage 2 pte fields to allow future changes to create stage 2
page tables.
MFC after: 1 month
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D23669
pmap's lock ensures that other operations on the pmap don't observe the
old mapping being broken before the new mapping is established. However,
pmap_kextract() doesn't acquire the kernel pmap's lock, so it may observe
the broken mapping. And, if it does, it returns an incorrect result.
This revision implements a lock-free solution to this problem in
pmap_update_entry() and pmap_kextract() because pmap_kextract() can't
acquire the kernel pmap's lock.
Reported by: andrew, greg_unrelenting.technology
Reviewed by: andrew, markj
Tested by: greg_unrelenting.technology
X-MFC with: r350579
Differential Revision: https://reviews.freebsd.org/D21169
The ARMv8 reference manual only states that the bit is reserved in
this case; following Linux's example, use it instead of a
software-defined bit for the purpose of indicating that a managed
mapping is writable.
Reviewed by: alc, andrew
MFC after: r350004
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21121
Previously the arm64 pmap did no reference or modification tracking;
all mappings were treated as referenced and all read-write mappings
were treated as dirty. This change implements software management
of these attributes.
Dirty bit management is implemented to emulate ARMv8.1's optional
hardware dirty bit modifier management, following a suggestion from alc.
In particular, a mapping with ATTR_SW_DBM set is logically writeable and
is dirty if the ATTR_AP_RW_BIT bit is clear. Mappings with
ATTR_AP_RW_BIT set are write-protected, and a write access will trigger
a permission fault. pmap_fault() handles permission faults for such
mappings and marks the page dirty by clearing ATTR_AP_RW_BIT, thus
mapping the page read-write.
Reviewed by: alc
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D20907
The initial raise in r336519 wasn't enough for using big resolution
(1920 x 1200 for example). Raise it again.
Reported by: bob prohaska <fbsd@www.zefox.net>
Tested by: bob prohaska <fbsd@www.zefox.net>
Approved by: re (gjb@)
Some driver (like efifb) needs to map more than the current L2_SIZE
Raise the size so we can map the framebuffer setup by the bootloader.
Reviewed by: cognet
pagetables. This sets both bits when entering an address we know shouldn't
be executed.
I expect we could mark all userspace pages as Privileged execute-never to
ensure the kernel doesn't branch to one of these addresses.
While here add the ARMv8.1 upper attributes.
Reviewed by: alc, kib (previous version)
MFC after: 1 week
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D10360
To maintain coherence between cache and DMA memory appropriate
shareability flags need to be set in the PTE regardless of SMP
option.
Reviewed by: wma
Obtained from: Semihalf
Sponsored by: Cavium
Differential Revision: https://reviews.freebsd.org/D6231
increased to 256TiB. The kernel address space can also be increased to be
the same size, but this will be performed in a later change.
To help work with an extra level of page tables two new functions have
been added, one to file the lowest level table entry, and one to find the
block/page level. Both of these find the entry for a given pmap and virtual
address.
This has been tested with a combination of buildworld, stress2 tests, and
by using sort to consume a large amount of memory by sorting /dev/zero. No
new issues are known to be present from this change.
Reviewed by: kib
Obtained from: ABT Systems Ltd
Relnotes: yes
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D5720
