riscv: drop l1pt argument from pmap_bootstrap()

And from struct riscv_bootparams. It is no longer needed.

Reviewed by: br, markj
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D45470

riscv: add stage 2 translation to pmap.

Add basic stage 2 translation support (guest-physical to host-physical).

RISC-V hypervisor spec[1] introduces new translation schemes: Sv32x4,
Sv39x4, Sv48x4 and Sv57x4.
In each case, the size of the incoming address is widened by 2 bits (e.g.
Sv39 becomes 41-bit system).
To accommodate the 2 extra bits, the root page table (only) is expanded
by a factor of four to be 16 KiB instead of the usual 4 KiB. The rest of
page table system (including PTE format) is similar.
This gives us 4x of memory space in each scheme, but it does not make sense
to support all that memory for now.
Allocate required amount of pages for the top directory in case of stage 2,
but leave it unused.

1. https://github.com/riscv/riscv-isa-manual/blob/main/src/hypervisor.adoc

Reviewed by: mhorne
Sponsored by: UKRI
Differential Revision: https://reviews.freebsd.org/D45481

arm64, riscv: removed unused struct pv_addr

No functional change.

Reviewed by: markj
MFC after: 3 days
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D45322

sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

pmap_{un}map_io_transient: Use bool instead of boolean_t.

Reviewed by: imp, kib
Differential Revision: https://reviews.freebsd.org/D39920

amd64: fix PKRU and swapout interaction

When vm_map_remove() is called from vm_swapout_map_deactivate_pages()
due to swapout, PKRU attributes for the removed range must be kept
intact. Provide a variant of pmap_remove(), pmap_map_delete(), to
allow pmap to distinguish between real removes of the UVA mappings
and any other internal removes, e.g. swapout.

For non-amd64, pmap_map_delete() is stubbed by define to pmap_remove().

Reported by: andrew
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D39556

sys: Consolidate common implementation details of PV entries.

Add a <sys/_pv_entry.h> intended for use in <machine/pmap.h> to
define struct pv_entry, pv_chunk, and related macros and inline
functions.

Note that powerpc does not yet use this as while the mmu_radix pmap
in powerpc uses the new scheme (albeit with fewer PV entries in a
chunk than normal due to an used pv_pmap field in struct pv_entry),
the Book-E pmaps for powerpc use the older style PV entries without
chunks (and thus require the pv_pmap field).

Suggested by: kib
Reviewed by: kib
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D36685

pmap_unmapdev/bios: Accept a pointer instead of a vm_offset_t.

This matches the return type of pmap_mapdev/bios.

Reviewed by: kib, markj
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D36548

Define _NPCM and the last PC_FREEn constant in terms of _NPCPV.

This applies one of the changes from
5567d6b4419b02a2099527228b1a51cc55a5b47d to other architectures
besides arm64.

Reviewed by: kib
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D36263

pmap_mapdev: Consistently use vm_paddr_t for the first argument.

The devmap variants used vm_offset_t for some reason, and a few places
explicitly cast bus addresses to vm_offset_t. (Probably those casts
along with similar casts for vm_size_t should just be removed and
instead permit the compiler to DTRT.)

Reviewed by: markj
Sponsored by: DARPA
Differential Revision: https://reviews.freebsd.org/D35961

riscv: Avoid passing invalid addresses to pmap_fault()

After the addition of SV48 support, VIRT_IS_VALID() did not exclude
addresses that are in the SV39 address space hole but not in the SV48
address space hole. This can result in mishandling of accesses to that
range when in SV39 mode.

Fix the problem by modifying VIRT_IS_VALID() to use the runtime address
space bounds. Then, if the address is invalid, and pcb_onfault is set,
give vm_fault_trap() a chance to veto the access instead of panicking.

PR: 265439
Reviewed by: jhb
Reported and tested by: Robert Morris <rtm@lcs.mit.edu>
Fixes: 31218f3209ac ("riscv: Add support for enabling SV48 mode")
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D35952

riscv: Add various pmap definitions needed to support SV48 mode

No functional change intended.

Reviewed by: jhb
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D34272

riscv: Rename struct pmap's pm_l1 field to pm_top

In SV48 mode, the top-level page will be an L0 page rather than an L1
page. Rename the field accordingly. No functional change intended.

Reviewed by: alc, jhb
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D34270

riscv: Implement pmap_mapdev_attr

This is needed for LinuxKPI's _ioremap_attr. This reuses the generic
implementation introduced for aarch64, and itself requires implementing
pmap_kenter, which is trivial to do given riscv currently treats all
mapping attributes the same due to the Svpbmt extension not yet being
ratified and in hardware.

Reviewed by: markj, mhorne
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D32445

riscv: Add a stub pmap_change_attr implementation

pmap_change_attr is required by drm-kmod so we need the function to
exist. Since the Svpbmt extension is on the horizon we will likely end
up with a real implementation of it, so this stub implementation does
all the necessary page table walking to validate the input, ensuring
that no new errors are returned once it's implemented fully (other than
due to out of memory conditions when demoting L2 entries) and providing
a skeleton for that future implementation.

Reviewed by: markj
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D31996

Add pmap_vm_page_alloc_check()

which is the place to put MD asserts about allocated pages.

On amd64, verify that allocated page does not belong to the kernel
(text, data) or early allocated pages.

Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D31121

riscv: Rename pmap_fault_fixup() to pmap_fault()

This is consistent with other platforms, specifically arm and arm64. No
functional change intended.

Reviewed by: jrtc27
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D30645

Introduce vm_page_astate.

This is a 32-bit structure embedded in each vm_page, consisting mostly
of page queue state. The use of a structure makes it easy to store a
snapshot of a page's queue state in a stack variable and use cmpset
loops to update that state without requiring the page lock.

This change merely adds the structure and updates references to atomic
state fields. No functional change intended.

Reviewed by: alc, jeff, kib
Sponsored by: Netflix, Intel
Differential Revision: https://reviews.freebsd.org/D22650

Implement pmap_page_is_mapped() correctly on arm64 and riscv.

We must also check for large mappings. pmap_page_is_mapped() is
mostly used in assertions, so the problem was not very noticeable.

Reviewed by: alc
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D21824

Move phys_avail definition into MI code. It is consumed in the MI layer and
doing so adds more flexibility with less redundant code.

Reviewed by: jhb, markj, kib
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D21250

Add kernel support for Intel userspace protection keys feature on
Skylake Xeons.

See SDM rev. 68 Vol 3 4.6.2 Protection Keys and the description of the
RDPKRU and WRPKRU instructions.

Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 2 weeks
Differential revision: https://reviews.freebsd.org/D18893

Implement per-CPU pmap activation tracking for RISC-V.

This reduces the overhead of TLB invalidations by ensuring that we
only interrupt CPUs which are using the given pmap. Tracking is
performed in pmap_activate(), which gets called during context switches:
from cpu_throw(), if a thread is exiting or an AP is starting, or
cpu_switch() for a regular context switch.

For now, pmap_sync_icache() still must interrupt all CPUs.

Reviewed by: kib (earlier version), jhb
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D18874

Implement transparent 2MB superpage promotion for RISC-V.

This includes support for pmap_enter(..., psind=1) as described in the
commit log message for r321378.

The changes are largely modelled after amd64. arm64 has more stringent
requirements around superpage creation to avoid the possibility of TLB
conflict aborts, and these requirements do not apply to RISC-V, which
like amd64 permits simultaneous caching of 4KB and 2MB translations for
a given page. RISC-V's PTE format includes only two software bits, and
as these are already consumed we do not have an analogue for amd64's
PG_PROMOTED. Instead, pmap_remove_l2() always invalidates the entire
2MB address range.

pmap_ts_referenced() is modified to clear PTE_A, now that we support
both hardware- and software-managed reference and dirty bits. Also
fix pmap_fault_fixup() so that it does not set PTE_A or PTE_D on kernel
mappings.

Reviewed by: kib (earlier version)
Discussed with: jhb
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D18863
Differential Revision: https://reviews.freebsd.org/D18864
Differential Revision: https://reviews.freebsd.org/D18865
Differential Revision: https://reviews.freebsd.org/D18866
Differential Revision: https://reviews.freebsd.org/D18867
Differential Revision: https://reviews.freebsd.org/D18868

Support RISC-V implementations that do not manage the A and D bits
(e.g. RocketChip, lowRISC and derivatives).

RISC-V page table entries support A (accessed) and D (dirty) bits. The
spec makes hardware support for these bits optional. Implementations that
do not manage these bits in hardware raise page faults for accesses to a
valid page without A set and writes to a writable page without D set.
Check for these types of faults when handling a page fault and fixup the
PTE without calling vm_fault if they occur.

Reviewed by: jhb, markj
Approved by: re (gjb)
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D17424

Revert r339421 due to unintended files included to commit.

Reported by: ian
Approved by: re (gjb)
Sponsored by: DARPA, AFRL

Support RISC-V implementations that do not manage the A and D bits
(e.g. RocketChip, lowRISC and derivatives).

RISC-V page table entries support A (accessed) and D (dirty) bits. The
spec makes hardware support for these bits optional. Implementations that
do not manage these bits in hardware raise page faults for accesses to a
valid page without A set and writes to a writable page without D set.
Check for these types of faults when handling a page fault and fixup the
PTE without calling vm_fault if they occur.

Reviewed by: jhb, markj
Approved by: re (gjb)
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D17424

Rework the list of all pmaps: embed the list link into pmap.

o Implement shared pagetables and switch from 4 to 3 levels page
memory system.

RISC-V ISA has only single page table base register for both kernel
and user addresses translation. Before this commit we were using an
extra (4th) level of pagetables for switching between kernel and user
pagetables, but then realized FPGA hardware has 3-level page system
hardcoded. It is also become clear that the bitfile synthesized for
4-level system is untested/broken, so we can't use extra level for
switching.

We are now share level 1 of pagetables between kernel and user VA.
This requires to keep track of all the user pmaps created and once we
adding L1 page to kernel pmap we have to add it to all the user pmaps.

o Change the VM layout as we must have topmost bit to be 1 in the
selected page system for kernel addresses and 0 for user addresses.
o Implement pmap_kenter_device().
o Create the l3 tables for the early devmap.

Sponsored by: DARPA, AFRL
Sponsored by: HEIF5

Import RISC-V machine headers. This is a minimal set required to compile
kernel and userland.

Reviewed by: andrew, imp, kib
Sponsored by: DARPA, AFRL
Sponsored by: HEIF5
Differential Revision: https://reviews.freebsd.org/D4554